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  • 1.
    Abboud, Mohamad Moulham
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Simulation of 3ph induction motor in Matlab with VVVF starting method2016Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Nowadays, three-phase induction motors are widely used on industrial and other types of processes. Therefore, accurate knowledge of an induction motor performance is very essential to have an idea of its operation conditions. This study is a sequel of a previous one, where Direct and Soft starting methods of three-phase motors has been simulated and compared. As in the previous study, the theory behind this one is based on representing the real motor by aset of equations and values in Matlab, forming a corresponding idealistic motor in a way where all the physical effects are similar. The motor is started under three different frequencies in the VVVF method using supporting simulation of the current, torque, speed,efficiency and power factor curves. The results of the three starting methods are then discussed and compared.

  • 2.
    Abrahamsson, Filip
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Björklin, Jimmy
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Hur muskelaktiveringen påverkas vid en inåtrotation i axelleden med och utan Activation Grip.2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Även om kaströrelsen i detalj skiljer sig mellan olika idrotter så är den biomekaniska funktionen i grunden densamma. Inom alla kastrelaterade idrotter återkommer den så kallade accelerationsfasen, här har det visat sig att inåtrotationen i axelleden har en hög korrelation med bollhastighet i kaströrelsen. Axelledens inåtrotatorer har alltså en viktig funktion för ett effektivt kast. En funktionell uppvärmning av dessa strukturer optimerar prestationsförmågan och minskar skaderisken. Kan träningsredskapet Activation Grip (AG) effektivisera uppvärmningen av den övre extremiteten hos kastidrottare?

    Syfte: Att undersöka och jämföra hur muskelaktiviteten i m. pectoralis major (PM), m. deltoideus anterior (DA), m. flexor carpi raidalis (FCR) och m. extensor digitoris communis (EDC) påverkas vid inåtrotation i axelleden med och utan träningsredskapet AG. Studien syftar även till att utvärdera AG som produkt.

    Metod: Muskelaktiviteten i PM, DA, FCR och EDC registrerades med hjälp av elektromyografi (sEMG) hos 18 aktiva idrottare inom överarmskastrelaterade idrotter (ålder 23,7 ± 5,7) vid inåtrotation i axelleden med maximal hastighet, jämfört med samma rörelse med AG och 30% belastning.

    Resultat: Resultatet visade på en signifikant högre muskelaktivering (p < 0.05) i DA, FCR, EDC under inåtrotationen med maximal hastighet. Hos PM sågs ingen signifikant skillnad i muskelaktivitet. AG fick över lag positiv respons från testdeltagarna. 

    Konklusion: Med resultatet i beaktande så skulle AG kunna kombineras tillsammans med andra uppvärmningsövningar för att få specifik aktivering i önskad muskulatur. Vidare studier gällande rörelse, motstånd och hastighet för att effektivisera användningen av AG bör göras. Även om AG fick positiv respons så bör produkten utvecklas ytterligare.

  • 3.
    Adriansson, Emma
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Turesson, Linnéa
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Klimatanalys av avloppsreningsverk: Analyser av två av Laholmsbuktens VA:s avloppsreningsverk med förslag på förbättringsåtgärder2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The intensified greenhouse effect is the biggest cause for a negative climate change. Global warming is a result of enhanced greenhouse effect and poses a potential threat for humans and its surrounding environment that can result in disastrous consequences. The rise in temperature is driven by increased human activity whereas the leading cause for emissions of greenhouse gases is the combustion of fossil fuels. The prominent source of emissions is from the following sectors: transport, industrial and energy. The task of reducing the emissions of greenhouse gases is both globally and internationally prioritized. Progress has been made although every potential source for emissions has to be investigated in order to reduce the total climate impact. Based on scientific research, wastewater treatment plants are also a contributing factor to the greenhouse effect by emissions of gases. This bachelor’s thesis is investigating two wastewater treatment plants and identifying which processes contribute to the climate impact. The climate impact is calculated with an Excel-based analyzing tool and the results show the Carbon Footprints for the treatment plants. The purpose of this paper is to present result acquired from the treatment plants and identify the processes that have the biggest impact on our climate. Afterwards, solutions derived from the analysis of results will be suggested to improve and bring additional help to the treatment plants with their climate work. In conclusion, it is determined that the treatment plants both have net emissions of greenhouse gases. The biggest contributor is the wastewater treatment and the use of biogas. Results from analysis show that some of the assumptions on emissions made in the tool make the initial results doubtful. Therefore, further research is needed on this subject in order to produce more reliable facts.

  • 4.
    Albinsson, John
    et al.
    Lund University.
    Brorsson, Sofia
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Lindgren, Finn
    Lund University.
    Rydén Ahlgren, Åsa
    Lund University.
    Cinthio, Magnus
    Lund University.
    Combined use of Iteration, Quadratic Interpolation and an Extra Kernel for high-resolution 2D particle tracking: a first evaluation2010In: 2010 ieee international ultrasonics symposium, New York: IEEE Press, 2010, p. 2000-2003Conference paper (Refereed)
    Abstract [en]

    A novel 2D particle tracking method, that uses 1) iteration, 2) fast quadratic sub-pixel estimation (with only 28 multiplications per movement), and 3) a previous kernel, has been evaluated and compared with a full-search block-matching method. The comparison with high-frequency ultrasound data (40 MHz) was conducted in silico and on phantoms, which comprised lateral, diagonal, and ellipsoidal movement patterns with speeds of 0–15 mm/s. The mean tracking error was reduced by 68% in silico and 71% for the phantom measurements. When only sub-pixel estimation was used, the decrease in the tracking error was 61% in silico and 57% for the phantom measurements. As well as decreasing the tracking error, the new method only used 70% of the computational time needed by the full-search block-matching method. With a fast method having good tracking ability for high-frequency ultrasound data, we now have a tool to better investigate tissue movements and its dynamic functionality.

  • 5.
    Alkiswani, Mutaz
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Spectrum conversion in solar cells industry: Novel model concept and steps towards commercialization2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Solar photovoltaic industry is a hot research field, massive attempts are going on all over the world to increase its productivity in different ways. One of the challenges for solar cells is the light spectrum mismatch losses, which referred to the part of solar spectrum that cannot be utilized to electricity by the conventional cells.

    Two ways have been suggested to overcome solar spectrum mismatch losses, the first is multi layered cells (tandem cells) with a different light behavior for each layer, and the second is spectrum conversion which is this researches subject.

    Spectral modification or conversion in solar cells industry has been studied and different lab scale models have been introduced. According to nanoscale journal, such technology may be the base of the next generation solar cells, mentioning specifically the use of luminescence down conversion and up conversion techniques to control the light spectrum on the solar cell, these endeavors targets to produce solar cells that is not subjugated to Shockley-Queisser maximum efficiency limit of 31%.

    This research aims to draw a map of various ideas introduced to incorporate similar technologies in solar cell products, beside further suggestion to enhance its technical behavior and to push the commercialization of the technology forward. This is expected to reveal clear image about technology’s future development map for the upcoming studies, and to create a motivation for further studies towards a commercial production scale.

    The proposed commercialized model will result in enhancing the maximum theoretical efficiency limit to 48% if all spectral mismatch loses have been eliminated. Quantum energy level diagrams have been illustrated to describe each model’s performance under a theoretical light spectrum.

  • 6.
    Al-Mimar, Samer
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science. Halmstad University.
    Integration of solar and wind power at Lillgrundwind farm.: Wind turbine shadow effect on solar farm atLillgrund wind farm.2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The supply of energy is a key factor in modern societies. As the old fossil sources for energy are dwindling, conflicts arise between competing nations and regions. Fossil energy sources also contribute to the pollution of the environment and emission of greenhouse gases.

    With renewable energy sources many of these drawbacks with fossil fuels can be eliminated as the energy will be readily available for all without cost or environmental impact.

    Combining the renewable energy sources will be very effective, particularly in commercial areas where lake of electricity is high. The cost of combining onshore wind and solar power plant is affordable. Furthermore there is no power failure or load shedding situation at any times. When it is manufactured in a large scale, cost of this integrated natural resources power generation system is affordable. Moreover there is no power failure or load shedding situation at any times. Therefore, it is the most reliable renewable power or electricity resources with less spending and highly effective production. ref [1].

    The thesis work would take planning of offshore renewable plant (Lillgrund) with considering the resources of renewable power. The study would take in account combining the Lillgrund wind farm with solar system and take close look into the advantage and disadvantage of combining the renewable resources together and figure out if such station can work in proper way and provide sufficient power production. The study would take in account the effect of each resource on other resource, also calculations would be done.

    The study site is Lillgrund in south of Sweden. The Lillgrund wind farm is the most important offshore wind power plant installed in Sweden with a total capacity of 110 MW, corresponding to 48 turbines. ref [2].

  • 7.
    Andersen, Emelie
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Aeshna viridis distribution and habitat choices in South and Central Sweden and the possibility to use a database as a tool in monitoring a threatened species2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Aeshna viridis, a dragonfly generally considered to be a specialist as it in most cases choosesStratiotes aloides as its habitat, have suffered badly from habitat loss and fragmentationsthroughout Europe under the last century as the human demand of land use have grown. It´sthereby considered near threatened on EU red list and is included in the Habitat Directive.This means that it is protected by EU law as all EU Member States is committed to protect,monitor and report back to EU the status of the species. Several European countries havedesigned protection plans for S. aloides to improve the preservation of A. viridis. My study inSouth and Central Sweden shows that the strong connection between A. viridis and S. aloidesmay not be consistent all over the distribution range of A. viridis, as my survey showed thatlarvae occur among other water plants when S. aloides is not present. Another aim in thisstudy was to evaluate the possibility to use occurrence data on A. viridis and S. aloides fromthe Species Observations System to monitor A. viridis distribution and dispersal. My studyimplies uncertainties of how well the datasets reflects reality and more research is necessarybefore clarifying if datasets could be a possible tool in conservation management of A. viridis.

  • 8.
    Andersen, Emelie
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Nilsson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Survival possibilities of the dragonfly Aeshna viridis (Insecta, Odonata) in southern Sweden predicted from dispersal possibilities2016In: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 20, no 2, p. 179-188Article in journal (Refereed)
    Abstract [en]

    We use public records from 1980 to 2014 to analyse survival of the EU Annex IV species Aeshna viridis in Sweden, a dragonfly strongly associated with the plant Stratiotes aloides. We clustered localities with S. aloides based on assumed dispersal abilities of A. viridis, using a dispersing radius of 2–100 km, calculating the proportion of sites with S. aloides that A. viridis is able to reach. If mean dispersal capability is high (40 km or above) 92.6 % or more of the localities are connected. For a good disperser, the probability of long-time survival is good. We further analysed the species richness of other Odonata and aquatic plants at 98 localities from the dataset. A. viridis co-occurred with more Odonata in the presence of S. aloides and running water but not in lakes. S. aloides sites had a higher number of other aquatic plants. Area had no impact on the occurrence of the species. For the present situation we surveyed 32 localities with known occurrence of the species. Only half of the sites for S. aloides contained any specimens while A. viridis occurred in the same number of sites. The species co-occurred in only 8 of 32 sites. In four sites A. viridis larvae appeared among Menyanthes trifoliata, Phragmites australis, Potamogeton natans and Sphagnum spp., indicating that at high latitudes A. viridis breeds among other species. Indirect monitoring based only on S. aloides would underestimate the number of populations of the dragonfly. © 2016 Springer International Publishing Switzerland

  • 9.
    Andersen, Niklas
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Ismail, Zahir
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Solel från ljudbarriär: längs Annetorpsvägen i Hyllie, Malmö2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.

    The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers. Along distance A, a PVNB with a total capacity of 19 kWp is expected to generate 18 000 kWh per year assuming realistic shadowing, which equals 6% losses compared to production without shadows. The PVNB along distance B with installed capacity of 37 kWp has no considerable problems with shadowing and is expected to generate 37 500 kWh per year. This gives a total production of 56 500 kWh per year.

    The combined investment costs (excluding costs for the actual noise barrier) for both power plants are assumed to be approximately one million SEK. Expected economical outcome is a negative capital value after 25 years, although a change of critical factors such as investment aid, investment cost, electricity prices and cost of capital may result in a more positive outcome. Production losses from shadowing and dirt seem to have a minimal effect on the outcome

    Despite uncertainty in the economical outcome, realizing the project would have several other positive effects such as reduction of carbon dioxide emissions and a positive impact on the public view of renewable energy.

  • 10.
    Andersson, Camilla
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Törnqvist, Lena
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Effekten av plyometrisk träning i starten för unga elitsimmare2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Previous studies on power have shown the relevance for athletic performance. Furthermore, there are several studies in plyometric training that demonstrate improvement in elasticity in sprint performance. However, few studies have been made on plyometric training for swimmers. We find it startling that no further studies have been made according to the positive effects that have been shown in swim performance. 

     

    The aim of this study was to investigate if the swimmer can increase in power output by performing plyometric training for eight weeks in link with regular exercise. In this study we used a test group of seven male and three female elite junior swimmers from Laxen, Halmstad.

     

    The tests conducted were 1RM squat, long jump, squat jump and the time between start and slide phase. We analyzed data with Dartfish. The training program was carried out twice a week for eight weeks to increase power output. The exercises were one leg bounding, truck jump, countermovement jump with medicine ball and vertical jump with weight.

     

    The improvements were significant in three of four tests. Mean pre-test of 1RM was 86.7 kg (± 16.8) and post-study had average increased to 95 kg (± 10.8). The results showed a significant difference (p = 0.05). Mean pre-test on the squat jump was 36.4 inches (± 5.5) and post-test had average increased to 41.8 cm (± 6.3). The results showed a significant difference (p = 0.001). Mean pre-test on the long jump was 2.42 meters (± 22.5) and post-test had average increased to 2.64 m (± 23.3). The results showed a significant difference (p = 0.001). The swim start showed no significant difference but the time was reduced by 9.2 percent. The greatest difference was in squat jump, which had an increase of 20 percent.

     

    The conclusion was that the swimmers gained a greater force after the training period. The tests in 1RM, squat jump and long jump had a significant difference. The swimmers had an increase in performance at the start of 9,2 percent. Although it was not a significant difference in the start, each percent increase in elite swimming is important.

  • 11.
    Andersson, Evelina
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    The 2-dimensional biomechanical modeling of the loads on the spine (L5-L1) during a “Back Walkover” maneuver in gymnastics2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Injuries in the female gymnast are common and it is important to understand the biomechanical factors responsible for injury. The Back Walkover maneuver requires one of the greatest amounts of lumbar hyperextension compared to other common gymnastic maneuvers. During the Back Walkover large lateral and vertical impact forces follows on the spine. The spine and muscles around the spine have to absorb generally large forces; therefore the loads on the back and certainly on the lower back are of significant interest. Additionally, it takes a lot of strength and a vast range of motion to perform gymnastic maneuvers such as The Back Walkover. It is of interest to study mechanical loads on a female gymnast since they show higher occurrences of stress-related pathologies of the lumbar spine.

    Therefore the purpose of this project was to examine the loads on the spine during the gymnastic maneuver Back Walkover. Tests on a single female gymnast were made at the sports engineering lab at the University of Adelaide in Australia. Using the 3D-camera system; Optitrack Motion Capture System and Kistler Force Plate, positional data for two dimensions, X-direction (anterior-posterior) and Z-direction (vertical), and ground force were received. Data received were progressed into a graph, diagrams and biomechanical calculations where forces for the vertebrae L1 were calculated in vertical and horizontal direction. The received forces were compared to vertical and horizontal forces in L1 during standing position. Together with developed videos this assisted to model the loads of the spine (L1) during the gymnastic maneuver the “Back Walkover”. The study has led to a deeper knowledge for the community about the risks for female gymnasts and has widened the experience of the project participant, as the project aimed. 

  • 12.
    Andersson, Gustav
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Ericsson, Emil
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Dark Ages Interferometer (DALI) Deployment Rover: Energy System2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The cosmic “Dark Ages” is the cosmic era between the epochs of recombination of cosmic microwave background and the formation of the first stars. The only signal from this epoch is from neutral hydrogen, which could represent one of the richest data sets in cosmology. In order to extract this data, NASA/JPL has proposed a rover mission to the farside of the moon to deploy several radio arrays. Here the arrays would gather data undisturbed by human interference. This thesis examines the possibility of using photovoltaic and electric batteries as an energy solution for a rover on the moon. The requirement for such a system to survive on the moon is discussed in a literature study. A proof of concept simulation using a Simulink model has also been done. The thesis concludes that a rover can deploy the radio array using solar energy. It would be able to hibernate through the night using radioisotope heating. It would need to wait for its batteries to charge before each night.

  • 13.
    Andersson, Julia
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Nielsen, Denise
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    En studie av eutrofierande näringsämnen i tre biflöden till Suseån: - Falkenbergs kommun, Halland2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Enligt ett av de 16 miljökvalitetsmålen, Ingen övergödning, ska halterna av eutrofierande ämnen inte ha någon negativ effekt på människors hälsa, den biologiska mångfalden eller vår möjlighet till ett hållbart brukande av mark och vatten. En stor bidragande orsak till den rådande övergödningsproblematiken i svenska vatten är läckage av främst näringsämnena kväve och fosfor från agrara och urbana källor.

    Hallands kustkommuner har sedan länge problem med övergödning och behovet för åtgärd är stort. Länet är särskilt utsatt för näringsläckage, delvis på grund av att en stor del av åkermarken utgörs av genomsläppliga jordar, vilka underlättar för vattnets framkomlighet och transport av näringsämnen, men även för att vattendrag har rätats ut av människan och för att naturliga våtmarker har tagits bort.

    I Halland rinner Suseån som är den femte största ån i länet. Problematiken i den övre regionen av dess avrinningsområde handlar främst om försurning, medan det i det nedre området främst handlar om övergödning och fysisk förändring av vattendragen.

    Vattenprovtagning utfördes i Suseån, samt i tre biflöden i den nedre delen av avrinningsområdet, vilken till stor del domineras av jordbruksmarker. De utvalda vattendragen var Käringasjöbäcken, Boarpsbäcken och Årstadbäcken.

    Resultatet av vattenprovtagningarna uppvisade överlag förhöjda halter av näringsämnen i alla biflöden till Suseån. De högsta halterna av både totalkväve och totalfosfor uppmättes i Boarpsbäcken och Årstadbäcken, vilka således har det största åtgärdsbehovet.

  • 14.
    Andersson, Martin
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Åhlund, Anton
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Solenergiutveckling i Halland2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Idag ökar antalet solenergianläggningar stort i Sverige, framförallt inom solelen. Samtidigt finns det inte någon långsiktig hållbar metod för att statistikföra solenergin. Det finns heller ingen regionsspecifik statistik, något som många svenska län och kommuner är intresserade av. Med bakgrund till detta behandlar arbetet frågor om solenergins utveckling med utgångspunkt för Hallands län, där fokus ligger på statistikinsamling.

    För att få en god uppfattning om utbyggnaden av solenergi i länet görs en statistiksammanställning av regionens solenergi. Samtidigt läggs förslag på framtida statistikmetoder för att bättre kunna följa solenergins utveckling i framtiden, regionalt såväl som nationellt. En jämförelse med andra län samt Tyskland och Danmark görs för att fånga upp idéer.

    Jämförelsen visar att Tyskland och Danmark idag har mer utvecklade metoder för statistikinsamling av solel medan de likt Sverige, har begränsad solvärmestatistik.

    Även en lönsamhetsberäkning för en mindre privat solcellsanläggning gjordes. Det visade sig vara lönsamt om anläggningen får skattereduktion eller investeringsstöd. Utan ekonomisk hjälp är lönsamheten lägre, även om utsikterna kan ändras beroende på elprisutvecklingen.

    Resultatet av den regionala statistiksammanställningen visar att Halland i början av år 2014 hade 1,6 GWh i årlig energiomvandling för solel respektive 7,3 GWh för solvärme. I länet finns 5,3 W/capita nätansluten solel jämfört med Sveriges 4,2 W/capita, vilket innebär att Halland har 21 % mer installerad effekt än Sverige i genomsnitt.

    De lämpligaste källorna för insamling av solenergistatistik är energibolag och installatörer där en kombination av dessa två källor ger en stor säkerhet och hög täckningsgrad. Finns bara resurser är detta det bästa alternativet. Rapportering går från dagens manuella metod till ett automatiserat system. En viktig ändring blir att rapportering av lokalisering införs vilket medför att regional statistik enkelt kan sammanställas.

  • 15. Andreasson, Mats
    et al.
    Werner, Sven
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Borgström, Margaretha
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB).
    Värmeanvändning i flerbostadshus och lokaler2009Report (Other academic)
    Abstract [en]

    Multi­family houses and service sector premises constitute 80 % of the customer stock in the Swedish district heating systems. The level of future heat use in these buildings will then have a strong influence on the future district heating economy and the cor­ responding investment demand. As a foundation for a planned study of future heat use, we have per­formed an extensive study of the current heat use for large buildings in Sweden. The input information for this study was the anonymous answers to the an­ nual enquiry of energy use in multi­family houses and service sector premises regarding 2006. Answers were available from 11253 buildings having 77.6 million square meters of residential areas and premises. By using scale factors, estimations could be made for the whole country having 310 million square meters of multi­family houses and premi­ ses. Hence, the enquiry sample constituted a large share of the whole building stock.The specific heat use was analysed by distribution, degree­days, construction year, ventila­tion system, performed conservation measures, and co­operation with other heat supply. A separate study was performed concerning high and low heat use buildings. The use of cold for cooling and water were also analysed.The results show that the individual variations are much larger than the systematic explana­tions for the parameters analysed. Just above 10% of the building spaces were high users of heat (above 200 kWh/m2). The average difference between Northern and Southern Sweden was small, implying a small climatic impact in heat use. The time period between 1965 and 1974 containing the national million dwelling program did not show dramatically higher heat use in the construction year analysis. Installed heat recovery in the ventilation gave a reduction in heat use with 11 kWh/m2 for multi­family houses. This small difference im­plies that the recovery efficiencies were only in average 20­30%. However, the heat recov­ery in service sector buildings was in average more efficient: About 50% in recovery effi­ciency. The conclusion from the conservation analysis is that the measures performed dur­ing the 10 years were done by late­comers rather than by early adopters, since the heat uses after measures in general correspond to the average level for all buildings. Out of 34000 heat pumps installed in the buil­ dings, about half of them were installed in buildings con­nected to district heating.But when more the one heat supply exists, district heat supply dominates, especially in multi­family houses.Typical users with high demands were buildings in the Västmanland and Norrbot­ ten coun­ties, fuel users, certain co­use with electricity, municipal premises, and small buildings. Typical users with low demands were buildings in the Halland county, heat pumps (but due to the systematic error of just accounting for the electricity supply to the heat pumps), state­owned buildings, and large buildings.The district heating companies can help their customers by identification of them as users with high, normal or low demands. This can be accomplished by adding infor­ mation about building space surfaces in the customer files. The heat use above the level 150 kWh/m2 was only 13 % for the multi­family houses and 14 % for the premises. Complete elimination of high use of district heat would then only give a limited, but significant reduction of the total district heat supply.

    Our 6 major conclusions from the project became: • Individual variations dominate compared to systematic causes considering heatuse in multi­family and service sector buildings. • Some systematic causes were identified. • A demand exists for more local measurements of electricity used for heating, thevolume of water use for hot water. • The district heating companies can help their customers to identify them as high,medium or low users of heat. • On short term, a significant potential exists for lower heat use in the Swedishmulti­family and service sector buildings. • More efficient heat use in building will probably be the most important competi­tor to district heat supply in the future.

  • 16.
    Arakelyan, Arsen
    et al.
    Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia (NAS RA), Yerevan, Armenia.
    Zakharyan, Roksana
    Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia (NAS RA), Yerevan, Armenia.
    Hambardzumyan, Marina
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Petrkova, Jana
    Laboratory of Immunogenomics and Immunoproteomics, Institute of Molecular and Translational Medicine, Medical Faculty of Palacky University, Olomouc, Czech Republic.
    Olsson, M. Charlotte
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Petrek, Martin
    Laboratory of Immunogenomics and Immunoproteomics, Institute of Molecular and Translational Medicine, Medical Faculty of Palacky University, Olomouc, Czech Republic.
    Boyajyan, Anna
    Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia (NAS RA), Yerevan, Armenia.
    Functional Genetic Polymorphisms of Monocyte Chemoattractant Protein 1 and C-C Chemokine Receptor Type 2 in Ischemic Stroke2014In: Journal of Interferon and Cytokine Research, ISSN 1079-9907, E-ISSN 1557-7465, Vol. 34, no 2, p. 100-105Article in journal (Refereed)
    Abstract [en]

    Recent findings indicated that monocyte chemoattractant protein 1 (MCP1) and its C-C chemokine receptor type 2 (CCR2) play a key role in ischemic stroke (IS) progression. This study was aimed at evaluating the potential association of the MCP1 gene (MCP1) rs1024611 (-2518 A>G) and CCR2 gene (CCR2) rs1799864 (V64I; 190 G>A) functional single nucleotide polymorphisms (SNPs) with IS in the Armenian population. For the purpose of this study, genomic DNA samples of 100 patients with the first-episode IS and 115 healthy subjects (controls) were genotyped for the selected SNPs using a polymerase chain reaction with sequence-specific primers. The results obtained demonstrated that while the CCR2 rs1799864 SNP genotypes were equally distributed among patients and controls, the frequency and carriage rate of the of the MCP1 rs1024611*G minor allele were higher in patients. While a potential association between IS and CCR2 rs1799864 SNP was evaluated for the first time, the latest finding was in agreement with the earlier data reported for some other populations. In summary, this study revealed no association of CCR2 rs1799864 SNP with IS, and a positive association between G minor allele of MCP1 rs1024611 SNP and IS in the Armenian population. Based on the present and earlier reported data, we concluded that the minor G allele of the MCP1 rs1024611 SNP might be considered a risk factor for IS.

  • 17. Aronsson, H.
    et al.
    Almqvist, J.
    Sundqvist, C.
    Timko, M.P.
    Dahlin, Clas
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    Characterization of the plastid import reaction of the pea NADPH-protochlorophyllide oxidoreductase (POR)1998In: The Chloroplast: From Molecular Biology to Biotechnology / [ed] Joan H. Argyroudi-Akoyunoglou, Horst Senger, New York: Springer-Verlag , 1998, p. 167-170Conference paper (Refereed)
    Abstract [en]

    NADPH: protochlorophyllide (POR) is a vital enzyme in the biosynthesis of chlorophyl where it catalyzes the reduction of Pchlide into Chlide in a light-dependent manner. POR is nucleus-encoded and imported into the plastids where it is found at the inner membranes. Together with its substrate and the co-factor NADPH it forms a ternary complex which is needed for catalytical activity. The anomaly of a decreasing POR level during active chlorophyll synthesis was cleared with the discovery of two different POR proteins, POR-A and POR-B, in barley and Arabidopsis thaliana. During greening, POR-A is negatively regulated by light both at transcriptional and proteolytical levels. In addition, the import of POR-A, but not POR-B, has been suggestedto require Pchlide in order to be translocated into the plastid. In this respect, POR-A differs from other known nucleus-encoded plastid proteins, and as it appears, this requirements represents a novel and exclusive import characteristic. In pea, only one POR gene has been found indicating that the situation for the regulation of POR import and accumulation is far from clear. We here present a characterization of the import conditions of the pea POR, including the potentional role of Pchlide inthe translocation step.

  • 18.
    Aronsson, Henrik
    et al.
    Department of Biology, Leicester University, Leicester, United Kingdom.
    Sundqvist, Christer
    Department of Plant Physiology, Göteborg University, Göteborg, Sweden.
    Dahlin, Clas
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    POR – import and membrane association of a key element in chloroplast development2003In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 118, no 1, p. 1-9Article in journal (Refereed)
    Abstract [en]

    The development of proplastids or etioplasts to chloroplast is visualized by the accumulation of chlorophyll in leaves of higher plants. The biosynthesis of chlorophyll includes a light-dependent reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide). This light-dependent step is catalysed by the nucleus-encoded NADPH:Pchlide oxidoreductase (POR, EC 1.6.99.1). POR is active within plastids and therefore has to be translocated over the plastid envelope membranes. The import of chloroplast proteins seems to follow a general import pathway using translocons at the outer and inner envelope membrane. POR cross-linking to Toc75, one of the major translocon components at the outer envelope membrane, indicates its use of the general import pathway. However, since variations exist within the so-called general import pathway one has to consider previous data suggesting a novel totally Pchlide-dependent import pathway of one POR isoform, PORA. The suggested Pchlide dependency of POR import is discussed since recent observations contradict this idea. In the stroma the POR transit peptide is cleaved off and the mature POR protein is targeted to the plastid inner membranes. The correct and stable association of POR to the membrane requires the cofactor NADPH. Functional activity of POR calls for formation of an NADPH–Pchlide–POR complex, a formation that probably takes place after the membrane association and is dependent on a phosphorylation reaction.

  • 19.
    Aronsson, Henrik
    et al.
    Department of Biology, Leicester University, United Kingdom.
    Sundqvist, Christer
    Department of Plant Physiology, Göteborg University, Göteborg, Sweden.
    Dahlin, Clas
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    POR hits the road: import and assembly of a plastid protein2003In: Plant Molecular Biology, ISSN 0167-4412, E-ISSN 1573-5028, Vol. 51, no 1, p. 1-7Article in journal (Refereed)
    Abstract [en]

    The biosynthesis of chlorophyll is a strictly light-dependent multistep process in higher plants. The light-dependent step is catalysed by NADPH:protochlorophyllide oxidoreductase (POR, EC.1.6.99.1), which reduces protochlorophyllide (Pchlide) to chlorophyllide (Chlide). POR is nucleus-encoded and post-translationally imported into plastids. It has been proposed that the import of a POR protein isozyme (PORA) is totally dependent on Pchlide and uses a novel import pathway. This proposal is based on findings that PORA import only occurs in the presence of Pchlide and that the presence of overexpressed precursor of Rubisco small subunit (pSS), a protein which is known to use the general import pathway, does not outcompete PORA import. Another study demonstrated that POR precursor protein (pPOR) can be cross-linked to one of the components in the translocation machinery, Toc75, in the absence of Pchlide, and that its import can be outcompeted by the addition of the pSS. This indicates that pSS and pPOR may use the same translocation mechanism. Thus, POR does not necessarily need Pchlide for import – which is in contrast to earlier observations – and the exact POR import mechanism remains unresolved. Once in the stroma, the POR transit peptide is cleaved off and the mature POR protein is associated to the plastid inner membranes. Formation of the correct membrane–associated, thermolysin-protected assembly is strictly dependent of NADPH. As a final step, the formation of the NADPH-Pchlide-POR complex occurs. When POR accumulates in the membranes of proplastids, an attraction of monogalactosyl diacylglycerol (MGDG) can occur, leading to the formation of prolamellar bodies (PLBs) and the development of etioplasts in darkness.

  • 20.
    Aronsson, Henrik
    et al.
    Department of Plant Physiology, Göteborg University, Göteborg, Sweden.
    Sundqvist, Christer
    Department of Plant Physiology, Göteborg University, Göteborg, Sweden.
    Timko, Michael P.
    Department of Biology, University of Virginia, Charlottesville, United States.
    Dahlin, Clas
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Characterisation of the assembly pathway of the pea NADPH:protochlorophyllide (Pchlide) oxidoreductase (POR), with emphasis on the role of its substrate, Pchlide2001In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 111, no 2, p. 239-244Article in journal (Refereed)
    Abstract [en]

    The homologous import and membrane association of a key enzyme for chlorophyll biosynthesis, the NADPH:protochlorophyllide (Pchlide) oxidoreductase (PAR, EC 1.6.99.1) into pea chloroplasts was investigated in vitro. The co-factor, NADPH, decreased binding of the precursor protein (pPOR) to the envelope membranes in the presence of ATP. The decrease of the binding reaction with NADPH was not observed with the precursor of the small subunit of Rubisco (pSS). To investigate possible substrate-dependency for the import reaction, internal Pchlide concentrations in the plastids were raised by either an addition of ÎŽ-aminolevulinic acid to isolated plastids or etiolation of the seedlings prior to plastid isolation. Increased amounts of plastid-bound Pchlide gave no observable differences in POR import. The capacity of POR and 11 different POR mutants, carrying charged-to-alanine scanning substitutions, to form a catalytically active POR-Pchlide-NADPH complex and to associate with the thylakoid membranes in a protease-resistant way were tested. Wild-type POR, as well as the mutants with charge substitutions in the N-terminal region of the protein, exhibited higher catalytic activity than the POR mutants carrying substitutions in the C-terminal region. Formation of a catalytically active complex did not, however, increase the association efficiency onto the thylakoids. We can, therefore, postulate that the import of pea POR into pea chloroplasts was not substrate-dependent, nor did formation of catalytically active complexes stimulate or inhibit the membrane association reaction of POR.

  • 21.
    Arvidsson, Ida
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Ringvall, Angelica
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Vindkraftens framtida scenarier2012Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    In several countries that have been early in the development of wind farms, there is today a second hand market for the used wind turbines. The European Union (EU) has established a waste hierarchy in order to minimize throwaway mentality. The second hand market is a part of this as the steps are to minimize, reuse, recycle, extract energy and landfill.

    In order to promote the development of renewable energy, there are energy certificates for the producers that provide it, wind power being one type of renewable energy. After 15 years the energy certificates for a specific wind turbine are no longer paid, and after that there are several different scenarios for the wind turbine. The scenarios investigated in this bachelor’s thesis are export of the wind turbine to countries that are not as far along as Sweden in their development towards renewable energy, selling in Sweden to individuals, and recycling of the wind turbine, as it mostly consists of metals and therefore is recyclable. In these three scenarios it is assumed that the sites for wind turbines are being reused for new larger wind turbines that produce more energy. Two additional scenarios are to reduce the number of wind turbines in a wind farm by half, in this way gaining access to free spare parts for the remaining wind turbines and continued operation, i.e. operate them for as long time as possible.

    To assure the decommissioning of the wind turbines and restoration of the site, there are several economical choices for the operator of the wind turbine. No matter what choice is made, the total amount should be 500 000 SEK according to the permission for the wind turbine. A Swedish authority, Miljöprövningsdelegationen, decides whether the operators choice in reassuring and make a decision based on that.

    To see which scenario is most profitable the economical part is crucial in this bachelor’s thesis. As a wind turbine is a large investment, the investment calculation is sensitive even to small changes. Inflation, interest rate, electricity price and energy certificate price can all vary a good deal but as it is almost impossible to predict the development of these factors, the inflation, interest rate and energy certificate price are all on a fixed level in this report. The electricity price is assumed to be dependent of the inflation solely. By using these assumptions and Microsoft Excel it has been clear that selling the wind turbine and reuse the site for a new larger wind turbine is the most profitable.

    Sweden has the goal to have 30 TWh, equivalent to 20 %, electricity from wind until year 2020. Today the part is 6.5 TWh, equivalent to 4 %. To make this goal reality it is necessary to make the permitting process easier and faster than the case is today. If Sweden compares to Denmark they already have 28 % electricity from wind and they aim for 50 %.

  • 22.
    Aspizua, Lucía
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    OFFSHORE FOUNDATION - A CHALLENGE IN THE BALTIC SEA2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    ABSTRACT

    This project deals with the search of the most proper offshore foundation to install in the Baltic Sea, in order to reduce costs and environmental impact. A pre-study was performed to define the Baltic Sea conditions and the required knowledge for the following steps. Afterwards, the specifications were set and clarified, and then the concept analysis phase was started. The analysis phase included the description of each one of the current foundations, those which are considered conventional foundations and those which are innovative ones. In order to evaluate these concept foundations, selection methods were used to assess the most relevant features of these foundations which should fulfil the requirements. The concepts ranking was studied and it led to the final results. Two different outcomes were obtained; such as, innovative concepts, which obtained the first position in this report; and conventional concepts, as a second finding. The continuous contact with different experienced professionals of this sector was essential during the whole project, in order to obtain advices, experienced knowledge and feedback.

  • 23.
    Assarsson, Karin
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Environmental exposure assessment of metals from reclaimed land in Halmstad harbour: Sweden  Part of an environmental risk assessment2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The harbour land fill in Halmstad has been described in the news as one of the most polluted areas in Halland County based on the a survey from the Swedish environmental protection agency. In order to identify the extent and severity of the situation several environmental investigations have been performed in this area. This report is based on available data from investigations and environmental reports from WSP, Höganäs AB, HEM and Halmstad municipality. This investigation focus on an “Area C” within the land fill where the main land fill material is i.a. slag from a steel work, construction waste, dredge spoil, waste from glass production and a casting shop. Of these material the focus have been on the metal rich slag from the steel work and its possible environmental impact. The environmental exposure of Hg, Pb, Cd, Cr, Zn, Ni, Mo and V have been calculated as an annual load from Area C. Unfortunately the data available for this investigation has not been complete, e.g. slag concentration data with corresponding leachate data was only obtained for one year. The groundwater data and land fill metal concentrations have been measured only once. This made it impossible to investigate e.g. annual variations like ageing effects of the material or weather variations, variation in the properties of the deposed slag material and statistical significance in differences could not be calculated. Further characterisation of the land fill would be worthwhile in order to be able to draw some conclusions.

    Calculations of the environmental load has been performed based on concentration in the slag, the land fill, the leachate data of the slag and groundwater concentrations. A model has been developed to calculate the weighted land fill metal concentration. The partitioning coefficient, Kd; between soil and liquid has been calculated and used to estimate the environmental load.

    It was assumed that the groundwater data was the most reliable data, which indicated that the exposure may be higher than from common soil, especially for Pb and Mo. Relating the environmental exposure values with guideline values based on MKM (less sensitive land use)-land using HQ (hazard quotient) indicates a decreasing risk in the order Pb>V>Mo. However, the exposure is well below that from MKM soil which could be assumed, according to Swedish environmental protection agency guideline values, to be an acceptable exposure.

  • 24.
    Atteia, A.
    et al.
    Depto. de Genética Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    van Lis, R.
    Depto. de Genética Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    Wetterskog, Daniel
    Department of Plant Physiology, Göteborg University, Göteborg, Sweden.
    Gutiérrez-Cirlos, E.-B.
    Department of Biochemistry, Dartmouth Medical School, Hanover, United States.
    Ongay-Larios, L.
    Unidad de Biología Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    González-Halphen, D.
    Depto. de Genética Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    Structure, organization and expression of the genes encoding mitochondrial cytochrome c1 and the Rieske iron-sulfur protein in Chlamydomonas reinhardtii2003In: Molecular Genetics and Genomics, ISSN 1617-4615, E-ISSN 1617-4623, Vol. 268, no 5, p. 637-644Article in journal (Refereed)
    Abstract [en]

    The sequence and organization of the Chlamydomonas reinhardtii genes encoding cytochrome c 1 ( Cyc1) and the Rieske-type iron-sulfur protein ( Isp), two key nucleus-encoded subunits of the mitochondrial cytochrome bc 1 complex, are presented. Southern hybridization analysis indicates that both Cyc1 and Isp are present as single-copy genes in C. reinhardtii. The Cyc1 gene spans 6404 bp and contains six introns, ranging from 178 to 1134 bp in size. The Isp gene spans 1238 bp and contains four smaller introns, ranging in length from 83 to 167 bp. In both genes, the intron/exon junctions follow the GT/AG rule. Internal conserved sequences were identified in only some of the introns in the Cyc1 gene. The levels of expression of Isp and Cyc1 genes are comparable in wild-type C. reinhardtii cells and in a mutant strain carrying a deletion in the mitochondrial gene for cytochrome b (dum-1). Nevertheless, no accumulation of the nucleus-encoded cytochrome c 1 or of core proteins I and II was observed in the membranes of the respiratory mutant. These data show that, in the green alga C. reinhardtii, the subunits of the cytochrome bc1 complex fail to assemble properly in the absence of cytochrome b.

  • 25.
    Averfalk, Helge
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Morgondagens effektiva fjärrvärme: En beskrivande litteraturstudie2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.

    The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand. Another benefit from combustion in units with higher capacity installed is that a higher control of emission with environmental impact is permitted. Additionally local environment change drastically when a few large supply units replace a large number of local supply units. It has also been shown that district heating can reduce greenhouse gas emissions in a cost efficient way. Thus being a part of the energy system to achieve the EU climate goals

    In Sweden, district heating is developed to a high degree. In connection with decreasing focus on expansion, the focus on maintenance and optimization and how district heating should look like in the future increases. In conjunction with lower heat demand from new and renovated buildings distribution cost will increase. For district heating to maintain competitiveness a development in distribution technology that move toward the next generation of distribution technology is necessary. Average temperatures today in Swedish district heating systems are for supply water 86 ° C and for return water 47 ° C. In the future temperature levels could decrease to current with temperatures down against 55 ° C supply temperature and 25-20 ° C return temperature. The latter system temperature levels moves towards the ideal possible.

    It is possible to distinguish four generations of district heating distribution technology. The differences between generations are essentially depending on temperature levels but also depend on state of matter. The first generation district heating used high-temperature steam for heat transfer and then the newer distribution technologies resulted in lower temperatures and change of phase, from gas to liquid. The third generation of district heating distribution technology meant lower temperature than the second generation, and likewise the fourth generation will have a lower temperature level than the third-generation distribution technology for district heating. The development is driven by the benefits of lower temperature levels. One of the more appealing benefits of lower supply temperature is the possibility to use low exergy heat, resulting in reduced need of primary energy. The potential heat sources where increased heat supply with lower system temperatures becomes available can be seen in the four next bullets.

    • Waste heat
    • Geothermal heat
    • Solar heat
    • Heat pump

    Other advantages obtained with lower temperature levels in heat distribution are.

    • Lower distribution losses
    • Higher electrical power efficiency in CHP
    • Increased efficiency in flue gas condensation
    • Increased capacity in the distribution network
    • Reduced need for pump power in the distribution network
    • Lower risk of serious scalding
    • Increased capacity in heat storage
    • Ability to use other materials for distribution at lower cost

    There seem to be a consensus in the literature that lower temperature levels in district heating systems are a desirable change. The reason for this is likely that there are mostly advantages of lower temperature levels. The drawbacks of lower temperature levels are negligible which make the risk of investment low.

  • 26.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Hansson, Anna
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Karlsson, Niklas
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Werner, Sven
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Mattsson, Marie
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Klimatgaser i Halland – en målinriktad analys med framtidsperspektiv2014Report (Other academic)
    Abstract [sv]

    Rapporten innehåller en analys av utsläppen av de sex klimatgaserna i Halland mellan 1990 och 2011, en skattning vad som kommer att genomföras till 2020 och förslag till åtgärder för att kunna leverera utsläppsreduktioner efter 2020. Resultaten visar att de halländska utsläppen har minskat med 20 procent sedan 1990, målet om 27 procent lägre utsläpp till 2020 kommer troligen att uppnås, transporter och jordbruk måste kunna leverera utsläppsreduktioner efter 2020, regionala plan- och styrdokument måste i större utsträckning kunna kvantifiera framtida utsläppsreduktioner samt att det behövs ett regionalt kompetenscenter i Halland för att länet ska kunna leverera utsläppsreduktioner i framtiden.

  • 27.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    Ingvarsson, Paul
    ÅF, Division Industry, Stockholm, Sweden.
    Persson, Urban
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    On the use of surplus electricity in district heating systems2014In: Proceedings from the 14th International Symposium on District Heating and Cooling: September, 6-10, 2014: Stockholm, Sweden / [ed] Anna Land, Stockholm: Swedish District Heating Association , 2014, p. 469-474Conference paper (Refereed)
    Abstract [en]

    Maintained balance between supply and demand is a fundamental prerequisite for proper operation of electric power grids. For this end, power systems rely on accessibility to various balancing technologies and solutions by which fluctuations in supply and demand can be promptly met. In this paper, balancing approaches in the case of surplus electricity supply, due to long-term, seasonal, or short-term causes, are discussed on the basis mainly of compiled experiences from the Swedish national power grid. In Sweden, a structural long-term electricity surplus was created in the 1980s when several new nuclear plants were commissioned and built. One of four explicit domestic power-to-heat solutions initiated to maximize the utilization of this surplus electricity, as export capacities were limited, was the introduction of large scale electric boilers and compressor heat pumps in district heating systems. In retrospective, this solution not only satisfied the primary objective by providing additional electricity demand to balance the power grid, but represents today – from an energy systems perspective – a contemporary example of increased system flexibility by the attainment of higher integration levels between power and heat sectors. As European power supply will be reshaped to include higher proportions of fluctuating supply technologies (e.g. wind and solar), causing occasional but recurring short-term electricity surpluses, the unique Swedish experiences may provide valuable input in the development of rational responses to future balancing challenges. The main conclusions from this study are that district heating systems can add additional balancing capabilities to power systems, if equipped with electrical heat supply technologies, hereby contributing to higher energy system flexibility. Consequently, district heating systems also have a discrete but key role in the continued integration of renewable intermittent power supply technologies in the future European energy system.

  • 28.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Essential Improvements in Future District Heating Systems2016In: Proceedings of the 15th International Symposium on District Heating and Cooling: September 4th - 7th, 2016, Seoul, South Korea / [ed] Rolf Ulseth & Kyung Min Kim, 2016, p. 194-200Conference paper (Refereed)
    Abstract [en]

    The major common denominator for future efficient fourth generation district heating systems is lower temperature levels in the distribution networks. Higher efficiencies are then obtained in both heat supply and heat distribution. Heat supply becomes more efficient with respect to combined heat and power, flue gas condensation, heat pumps, geothermal extraction, low temperature excess heat, and heat storage. Heat distribution becomes more efficient from lower distribution losses, less pipe expansion, lower scalding risks, and plastic pipes. The lower temperature levels will be possible since future buildings will have lower temperature demands when requiring lower heat demands. This paper aims at providing seven essential recommendations concerning design and construction strategies for future fourth generation systems. The method used is based on a critical examination of the barriers for lower temperature levels and the origins of high return temperatures in contemporary third generation systems. The two main research questions applied are: Which parts of contemporary system design are undesirable? Which possible improvements are desirable? Key results and the corresponding recommendations include temperature levels for heat distribution, recirculation, metering, supervision, thermal lengths for heat exchangers and heat sinks, hydronic balancing, and legionella. The main conclusion is that it should be possible to construct new fourth generation district heating networks according to these seven essential recommendations presented in this paper.

  • 29.
    Ayed, Sami
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Assessment of energy losses for the climate shell in a commercial passenger ship2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The shipping industry is facing a major challenge. Current and future emission requirements result in considerably increased operating costs. Studies have shown that it is a large potential to reduce the ship operating costs by energy effectivisation. The focus has naturally been on systems with major energy losses, such as combustion engines, propulsion and hull friction.

    A passenger ship like Stena Danica with a big climate controlled accommodation could be expected to have major heat losses. By calculating transmission losses from walls, ceilings, window sections, and the energy losses by ventilation, a general view of how heat losses are distributed has been established. The primary goal is to gather information that could be useful in further energy improvements.

    Due to lack of information and deficiently measured data have several assumptions and simplifications been made. Despite this, the calculations can be considered as indicative. The results indicated that about 50 percent of the energy losses occur by ventilation and the remaining consists of transmission losses in windows sections and climate shell, (About 25% each). The focus in the calculations has been to estimate the accommodations heating demand. Energy improvements that reduce the heating demand will reduce the cooling demand as well. This may be a greater incentive for measures as the air conditioning system are powered with higher energy quality; electricity. Besides shore power the electricity is mainly generated by diesel generators. The energy used for heating is mainly produced by waste heat or is supplied by shoreside district heating.

    Upgrading the ventilation systems are considered to be the most economic method to reduce the heat losses in the accommodation area. The ship's ventilation systems lack any type of demand control, this causes excessive energy losses as the ventilation demand vary greatly regarding to time of the day and numbers of passengers.

    The ship has a large amount of single pane windows that also contributes to large energy losses. To upgrade or replace these are considered to be more economic than to improve the insulation on the rest of the climate shell as it doesn’t affect the interior to the same extent. The latter may be worth considering in case of a major renovation of the vessel.

  • 30.
    Bakker, Roel H.
    et al.
    Department of Applied Research in Care, University Medical Center Groningen, University of Groningen, The Netherlands.
    Pedersen, Eja
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    van den Berg, Godefridus Petrus
    GGD Amsterdam Public Health Service, Amsterdam, The Netherlands.
    Stewart, R.E.
    Department of Community & Occupational Health, University Medical Center Groningen, University of Groningen, The Netherlands.
    Lok, W.
    Department of Applied Research in Care, University Medical Center Groningen, University of Groningen, The Netherlands.
    Bouma, J.
    Department of Health Care, Science shop, University Medical Center Groningen, University of Groningen, The Netherlands.
    Impact of wind turbine sound on annoyance, self-reported sleep disturbance and psychological distress2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 425, p. 42-51Article in journal (Refereed)
    Abstract [en]

    Purpose of the research: The present government in the Netherlands intends to realize a substantial growth ofwind energy before 2020, both onshore and offshore. Wind turbines, when positioned in the neighborhood ofresidents may cause visual annoyance and noise annoyance. Studies on other environmental sound sources,such as railway, road traffic, industry and aircraft noise show that (long-term) exposure to sound can havenegative effects other than annoyance from noise. This study aims to elucidate the relation between exposureto the sound of wind turbines and annoyance, self-reported sleep disturbance and psychological distress ofpeople that live in their vicinity. Data were gathered by questionnaire that was sent by mail to a representativesample of residents of the Netherlands living in the vicinity of wind turbinesPrincipal results: A dose–response relationship was found between immission levels of wind turbine soundand selfreported noise annoyance. Sound exposure was also related to sleep disturbance and psychologicaldistress among those who reported that they could hear the sound, however not directly but with noiseannoyance acting as a mediator. Respondents living in areas with other background sounds were less affectedthan respondents in quiet areas.Major conclusions: People living in the vicinity of wind turbines are at risk of being annoyed by the noise, anadverse effect in itself. Noise annoyance in turn could lead to sleep disturbance and psychological distress. Nodirect effects of wind turbine noise on sleep disturbance or psychological stress has been demonstrated,which means that residents, who do not hear the sound, or do not feel disturbed, are not adversely affected.

  • 31.
    Bay, Bjorn
    et al.
    Institute of Odontology, Karolinska Institutet, Huddinge, Sweden.
    Hilliges, Marita
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Weidner, Christian
    Department of Physiology 1, University of Erlangen, Erlangen, Germany.
    Sandborgh-Englund, Gunilla
    Institute of Odontology, Karolinska Institutet, P.O. Box 4064, SE-141 04 Huddinge, Sweden.
    Response of human oral mucosa and skin to histamine provocation: laser Doppler perfusion imaging discloses differences in the nociceptive nervous system2009In: Acta Odontologica Scandinavica, ISSN 0001-6357, E-ISSN 1502-3850, Vol. 67, no 2, p. 99-105Article in journal (Refereed)
    Abstract [en]

    Objective. To investigate the existence of histamine-excitable nerve fibers in the oral mucosa and to compare the response to histamine provocation in healthy volunteers with that in a small group of patients with chronic oral pain. Material and methods. Thirteen healthy volunteers and six patients suffering from chronic oral pain took part in the study. Blood perfusion was monitored in the hard palate, the tongue, and the skin of the cheek using laser Doppler perfusion imaging (Perimed; Sweden). Baseline scannings were performed, followed by 15 scannings after iontophoresis of histamine (1%). A free description of the sensations was then obtained from the participants after finishing the measurements. Results. Compared to pre-histamine scanning, histamine application resulted in a considerable increase in blood perfusion in all regions (p0.001) that was significantly higher in skin than in oral mucosa (p0.001). There were no significant differences between the healthy volunteers and the patients regarding baseline blood flow, increased blood perfusion, or flare size after histamine provocation. The sensory impression was reported to be more persistent and intense in the skin than in the oral mucosa. No effect on mucosa could be detected by visual inspection. Conclusions. Intra-oral flare could be induced by activating histamine-excitable nerve fibers. Both duration and intensity of the flare were considerably less pronounced than in the control skin site. Histamine application was not clearly associated with itch.

  • 32.
    Belka, Linda
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Larsson, Jonathan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Rullstolshjälpmedel för tetraplegiker: Utveckling och utvärdering av en prototyp2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An estimated 2000 people are today living in Sweden with a diagnosis of tetraplegi. The cause of the injury is trauma towards the cervical spine resulting in paralysis of the trunk as well as the lower limbs. The higher the positioning (i.e. the lower numbering of the vertebrae) of the cervical vertebrae damaged by the trauma, the more functions are lost in the upper extremities. When this happens, the traditional way of wheelchair propulsion with the push rim becomes less convenient. During the project, a prototype aid was developed. With the help of the aid, the users are able to change their pattern of movement when using the wheelchair. The new pattern allows the tetraplegi users to use their power in a tangential direction to the wheel. In addition they will be using mainly their strongest muscles in their arms, optimising their ability to move forward.

    In the project, dynamic product development was applied, focusing on the users in order to develop a user-friendly prototype which meets their requirements. To achieve this goal the project group collected data from people working with the rehabilitation of tetraplegics as well as people involved in the supply and distribution of rehabilitation aids. This benchmarking as well as meetings with intended users was helpful when gathering information. The prototype was developed with in close cooperation with various companies.

    User tests showed that the prototype could help increase maximum propulsive force required to climb over a threshold, for one of the two test persons. The prototype gave, however, a decrease in experienced maneuverability, as all of the components of the prototype were not working optimally. Further tests and development are needed before the product can operate for an extended use and for a wider target group.

  • 33.
    Bengtsson, Oscar
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Petersson, Johan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    MAXIMAL STYRKA I ENBENSKNÄBÖJ KORRELERAR MED ACCELERATIONS KAPACITET OCH AGILITY2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Strong correlations have been found between strength in the two leg squat exercise and sprint performance in various distances but not in sprint performance in agility. In studies the most common way to test squat strength is on two legs.

    The purpose in this study was to investigate the correlation between maximal strength in a bulgarian split squat in a smith machine and speed in various sprint distances and agility.

    The test group were 19 men (age 23,9 ± 2,5 ) with regular experience in intermittent team sports. Sprint tests at 5, 10 and 20 meter and the zigzag agility test were performed. The bulgarian split squat was performed in a smith machine with the barbell on the shoulders to a depth of 110 degrees between tibia and femur.

    The results show significant correlation between maximal strength in the bulgarian split squat and sprint capacity in the 5 and 10 meter sprint test as well as the agility test. Maximal strength relative to bodyweight showed significant correlation with the 5 and 20 meter sprint as well as the agility test. The zigzag agility test also showed strong correlation between all distances in the sprint tests.

    Our conclusions based on the results are that the bulgarian split squat puts big demands on balance, stability and coordination and is therefore a specific movement towards sprints that include changes of direction. The maximum strength in a split squat is a good predictor for sprint capacity in sprints. Implementing one leg exercises in the strength and conditioning routine can be good for athletes in intermittent sports to improve the sports specific sprint capacity.

  • 34.
    Bengtsson, Simon
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energy Science.
    Economic and environmental implications of a conversion to natural gas.2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 35.
    Berg, Nichlas
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Kårhammer, Per
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Säsongslagring av spillvärme: Ersättning av Halmstad fjärrvärmenäts spetslastanläggning2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden, a great deal of energy is used for residential and commercial heating. To fulfill the ever increasingly need for heat, new heating plants is built to complement the district heating system. At the same time there is unused energy in industry, which produces heat as an unwanted byproduct.

    This report evaluates the possibility to use this byproduct to supply energy to a district heating system and store it in seasonal heat storage. When the heat demand increases during the cold season of the year, the seasonal heat storage contributes with heat energy.

    The idea is to replace parts of the heating plants in Halmstad with heat storage and waste heat. The aim is to exclude usage of all fossil fuels. This report will also evaluate the economical prerequisites and environmental benefits in replacing biofuels.

    A steelworks company, Höganäs Halmstadverken, is situated in Halmstad. This industry could contribute with surplus heat, which is calculated in this report.

    With help of calculations and simulations in Microsoft Excel, a system with adequate heat storage method and surplus heat from local industry is formed. This system is optimized concerning economic and environmental matters.

    The results reveal that Halmstad's conditions are favorable to integrate pit heat storage and there is potential to deliver waste heat from Höganäs Halmstadverken steelworks. Sizes of seasonal heat storage is optimized to 200 000 m3 for replacing fossil fuels respectively 550 000 m3 for replacing fossil fuels and biofuels. Waste heat effect is calculated to 15 MW.

    The economical calculations results in an annual profit up to 8 million SEK with a payoff equal to 8 years. The environmental benefits consisting of reduced greenhouse gases are calculated to 4 800 tons carbon dioxide equivalents annually.

  • 36.
    Berggren, Thomas
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Bioscience.
    Does type of habitat affect tick-burden in roe deer (Capreolus capreolus) neonates?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study was investigating the relationships between: 1) habitat type and tick abundance, 2) habitat type and tick load on fawns, and 3) tick load and fawn survival. During two years and in two study areas, 105 fawns (57 fawns in Bogesund and 48 fawns in Grimsö) have been captured by hand and equipped with a radio-transmitter. The fawns’ positions have then been triangulated almost every day until they died or had at least 30 positions. The surviving fawns were recaptured when they were estimated to have a weight of 3.6 kg. Ticks were collected from the fawns during both the capture and the recapture. By using the flagging-method, in which a white sheet is dragged along the ground, ticks were also collected from the vegetation. A vegetation map was used to determine the habitat on transects and the home range of the fawns. The study areas showed different results regarding in which habitat the ticks were found. At Grimsö ticks seems to favor deciduous forest and mixed forest not on mires. At Bogesund the favored tick habitat was instead coniferous forest with trees between five to fifteen meters. In Bogesund there was a positive correlation between tick-burden and percent of coniferous forest on lichen-dominated areas that covered fawn home ranges. No relationship could be found between ticks and the survival of the fawns. A positive correlation between surviving days and tick load during first capture could instead be found on fawns that died within 30 days.

  • 37.
    Berglund, Björn
    et al.
    Linköping University, Division of Medical Microbiology, Department of Clinical and Experimental Medicine, Linköping, Sweden.
    Khan, Ghazanfar Ali
    Department of Chemistry, Umeå University, Umeå, Sweden.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Ehde, Per Magnus
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Fick, Jerker
    Department of Chemistry, Umeå University, Umeå, Sweden.
    Lindgren, Per-Eric
    Linköping University, Division of Medical Microbiology, Department of Clinical and Experimental Medicine, Linköping, Sweden.
    Efficient removal of antibiotics in surface-flow constructed wetlands, with no observed impact on antibiotic resistance genes2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 476-477, p. 29-37Article in journal (Refereed)
    Abstract [en]

    Recently, there have been growing concerns about pharmaceuticals including antibiotics as environmental contaminants. Antibiotics of concentrations commonly encountered in wastewater have been suggested to affect bacterial population dynamics and to promote dissemination of antibiotic resistance. Conventional wastewater treatment processes do not always adequately remove pharmaceuticals causing environmental dissemination of low levels of these compounds. Using constructed wetlands as an additional treatment step after sewage treatment plants have been proposed as a cheap alternative to increase reduction of wastewater contaminants, however this means that the natural microbial community of the wetlands becomes exposed to elevated levels of antibiotics. In this study, experimental surface-flow wetlands in Sweden were continuously exposed to antibiotics of concentrations commonly encountered in wastewater. The aim was to assess the antibiotic removal efficiency of constructed wetlands and to evaluate the impact of low levels of antibiotics on bacterial diversity, resistance development and expression in the wetland bacterial community. Antibiotic concentrations were measured using liquid chromatography-mass spectrometry and the effect on the bacterial diversity was assessed with 16S rRNA-based denaturing gradient gel electrophoresis. Real-time PCR was used to detect and quantify antibiotic resistance genes and integrons in the wetlands, during and after the exposure period. The results indicated that the antibiotic removal efficiency of constructed wetlands was comparable to conventional wastewater treatment schemes. Furthermore, short-term treatment of the constructed wetlands with environmentally relevant concentrations (i.e. 100-2000 ng x 1(-1)) of antibiotics did not significantly affect resistance gene concentrations, suggesting that surface-flow constructed wetlands are well-suited for wastewater treatment purposes. (c) 2014 Elsevier B.V. All rights reserved.

  • 38.
    Bergman, Lina
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Algotsson, Marcus
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Effekten av 6 veckor unilaterala knäböj, med eller utan isokinetiskt motstånd, på power och sprinttid på is hos manliga ishockeyspelare2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ice-hockey are physically demanding. To be able to perform during a game it is required thatthe players have a high maximum leg strength and power. A bilateral squat is a valid and widespread exercise for improving muscle strength and power in the legs. Even more specific forice-hockey is the unilateral squat. During an isokinetic movement the velocity is pre-set andtherefore constant, while the force can be altered during the movement. Most isokineticsystems have been designed for unilateral training, but in terms of isokinetic multi-jointexercises, such as the squat, there seems to be no research until this day.The purpose of this study was to examine the effect of six weeks unilateral strength training(squat), either through traditional or isokinetic training, on power-output and 17.3 m sprinttime on ice among male junior ice-hockey players.20 elite male ice-hockey players, 18-19 years of age, was randomly divided in two differenttraining groups. One group (QG) did isokinetic unilateral squats in 1080 Quantum, with anangle of 110o degrees in the knee joint. The other group (SG) did traditional unilateral squatsin a Smith-machine, also with an angle of 110o degrees in the knee joint. The period oftraining was set to six weeks. Both groups participated in pre- and post-tests consisting ofsprint on ice and peak power in unilateral and bilateral jump squats.A significant improvement was seen with QG in peak power performed on both legs(p=0,004). SG had a significant improvement in unilateral squat performed on the right leg(p=0,018). A tendency to significant improvement was seen with QG in the ice-sprint(p=0,059).Isokinetic unilateral squat in a Smith-machine with a concentric velocity set to 0,2m/sec andan eccentric velocity set to 4,0m/sec with a maximum force is an effective exercise toimprove power-output on two legs, perhaps also to improve sprint ability on ice, among icehockeyplayers. It is difficult to draw conclusion about the results from this study whetherisokinetic unilateral squats is an effective method to improve the power compared totraditional unilateral squats in a Smith-machine with maximum speed.

  • 39.
    Bergman, Stefan
    et al.
    FoU Spenshult, Halmstad, Sweden; The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden & Lund University, Lund, Sweden.
    Bremander, Ann
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine. FoU Spenshult, Halmstad, Sweden & Lund University, Lund, Sweden.
    Bergman, Anna-Carin
    Sannarpsgymnasiet, Halmstad, Sweden.
    Brorsson, Sofia
    Health and Welfare, Dalarna University, Falun, Sweden.
    Chronic Widespread Pain in Adolescents Is Highly Associated to Stress and Anxiety2015In: Arthritis & Rheumatology, ISSN 2326-5191, E-ISSN 2326-5205, Vol. 67, no Suppl. S10, article id 917Article in journal (Refereed)
    Abstract [en]

    Background/Purpose: Chronic widespread pain (CWP), one of the hallmarks of fibromyalgia, is not uncommon in adolescents and it has previously been shown that adolescents with pain often become young adults with pain. CWP often co-varies with anxiety, depression, and stress symptoms in adults, but the knowledge regarding this is small in youth and young adults.

    The aim was to study the associations between CWP, anxiety, depression and stress in adolescents attending first year of high school.

    Methods: A computerized questionnaire to 296 adolescents attending Swedish high school, with validated questions regarding presence and distribution of pain (Epipain mannequin), stress symptoms (ELO question), anxiety and depression (Hospital Anxiety and Depression Scale – HADS), and health related quality of life (HRQL as measured by EQ5D). Pain was considered chronic when persistent for more than three months, and the subgroup CWP was defined according to the 1990 ACR criteria for fibromyalgia. Statistical analyses in SPSS v21 with comparison of means by Student’s t-test and proportions by chi2-test or Fischer’s exact test.

    Results: 257 (87%) out of 296 eligible students, mean (SD) age 16.1 (0.7) and 65.8% girls, responded to the questionnaire.  Prevalence of chronic pain was 20.8% and that of the subgroup CWP was 4.7%, without any gender differences (boys 18.2% vs girls 22.2%; p=0.224, and 3.4% vs 5.4%; p=0.692). High level (4 or 5 on a 5 point scale) of stress symptoms were less common in boys (16.0% vs 28.2%; p=0.015), as was possible or probable anxiety (17.1% vs 44.4%; p<0.001), but not depression (10.3% vs 12.5%; p=0.764). Students with high level of stress reported CWP five times more often than those with less stress (30.4% vs 5.8%; p=0.001). Students with probable anxiety reported CWP ten times more often than students with no anxiety (17.6% vs 1.8%; p=0.001), and CWP was also more common, but not statistically significant, in students with probable depression (20.0% vs 3.1%; p=0.163). Those reporting CWP had significantly lower HRQL (0.58 vs 0.87; p=0.038) than students with no chronic pain.

    Conclusion: The high prevalence of chronic pain and the strong associations between CWP and reports of stress and anxiety in adolescents highlights that a multifactorial background to chronic pain must be considered early in life. An apparent lower score in EQ5D also indicates that the presence of CWP has an marked impact on HRQL also in adolescents.

  • 40.
    Bergqvist, Mathias
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Hip strength in Swedish soldiers: A correlation study between gluteus medius muscle strength and development of valgus during 2000 meter run with external load2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
  • 41.
    Bernhardsson, Lina
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    EMG analys av M. Gluteus medius i sex kroppsviktsövningar2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background. Body weight resistance training has many applications, such as to become better at a sport, prevent lifestyle diseases, or prevent and rehabilitate injuries. M. gluteus medius (GMed) is a muscle that has strong correlation to injury of the foot, knee, hip and lower back. Research using electromyography (EMG) has examined exercises with the most muscle activity in GMed. Bilateral GMed has not been investigated in previous research for various exercises. More often it is only the dominant leg that is analysed. Aim. The purpose of this study was to investigate whether there was any difference in muscle activity of the GMed for the dominant and the non-dominant leg, total and individual, between A) the same exercise conducted bilaterally and unilaterally, b) similar exercises conducted standing and lying. Furthermore, the purpose was to study which of the six selected body weight exercises, hip thrust and squat performed on one and two legs as well as standing and lying hip abduction, yielded the highest muscle activation in GMed. Methods. 15 subjects (five men and ten women) participated in this study. Subjects warmed up and then preformed a maximal voluntary isometric contraction (MVIC), which was used as a reference value. Test subjects performed six bodyweight exercises, bilateral and unilateral hip thrust and bilateral and unilateral squat and lying and standing hip abduction. Hip thrust and squat on one leg was performed on the dominant leg, the abduction motion in standing and lying hip abduction was performed with the dominant leg. Result. There was a significantly higher muscle activity in the dominant leg in all unilateral exercises compared to bilateral exercises. In standing hip abduction there was a significantly higher muscle activity in the non-dominant side compared to the lying hip abduction and opposite results were measured in the dominant leg. When the total muscle activity was calculated from both right and left sides, hip abduction gave highest muscle activity, unilateral exercises gave higher muscle activity than the same bilateral exercises. Conclusion. For a healthy and injury-free population standing hip abduction is recommended as the most effective of the exercises tested when it comes to training GMed. If variety of exercises for GMed and continued high activity are wanted, this study recommends unilateral exercises in front of bilateral exercises.

  • 42.
    Birgersson, Rikard
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Eliasson, Eric
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Unilateralt och bilateralt genomförande av bänkpress och dess påverkan på varandra sett till muskelaktivering, effekt, och kraftutveckling2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: It has been studied whether strength-exercises performed with two arms (bilateral) leads to better performance when compared to exercises performed with only one arm (unilateral), and it has been shown that both implementations result in similar results after a short training period. At the same time, research shows that mixed results between different implementations in terms of muscle activation and force development exists.

    Objective: The main purpose of this study was to see the effect of unilateral or bilateral warm-up in the bench press and its influence on subsequent unilateral and bilateral performance in the bench press, investigating the factors: muscle activation, power, and force development. A secondary purpose was to relate the results of the study to bilateral index, to see if bilateral deficit or bilateral facilitation dominates.

    Method: Strength-trained men (n = 13, age 25 ± 3 years) warmed up with two different implementations (unilateral or bilateral), and after each individual warm-up they performed three submaximal lifts (40 and 80% of 1RM) in unilateral and bilateral bench press. Muscle activity, power, and force development were measured in muscles pectoralis major, anterior deltoid, and triceps brachii, after each individual warm-up during three submaximal lifts (40 and 80% of 1RM) in unilateral and bilateral bench press.

    Results: Significant results were found in unilateral performance in power and force development after unilateral warm-up (184 ± 36 W and 164 ± 31 W; 416 ± 76 N and 412 ± 74 N) compared with bilateral warm-up (p = 0.05). There were no significant differences between the different implementations in bilateral performance. Significant differences were neither found in the muscle activation of any of the implementations. The study also found evidence of a difference between the test participants regarding bilateral deficit and bilateral facilitation in terms of power and force development, where the majority of the test participants had bilateral facilitation.

    Conclusion: Regardless of warm-up, no difference was seen in the strength-trained men regarding muscle activation in the bilateral or unilateral bench press, however, the warm-up  was of importance to performance. Therefore, unilateral warm-up should be applied before unilateral performance, as this showed significant improvement. Although no significant improvement was observed, a bilateral warm-up should also preceed a bilateral performance.

  • 43.
    Björk, Oscar
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Post-activation Potentiation in Moderately Heavy Squats following a Heavy Pre-load Squat2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Post-activation potentiation (PAP) is a phenomenon where force output is acutely enhanced

    following muscular contraction. Previous research has documented enhanced performance in

    power-type light exercise following a heavy pre-load, such as vertical jumps following heavy

    squats. To date, the effect of PAP on moderately heavy exercise following a heavy pre-load

    has not been investigated. Purpose: The purpose was to examine whether PAP could be

    elicited in moderately heavy squats following a heavy squat pre-load, and if so, what intensity

    (as percentage of one repetition-maximum [1RM]) of pre-load elicited the highest PAP effect

    (measured as mean power, mean force and number of repetitions performed). Subjects:

    Seventeen resistance-trained males (age 24±2 years, length 182±8 cm, body mass 84.7±13.1

    kg, squat 1RM 147.6±29.6 kg) with at least 2 years of experience of the squat exercise.

    Methods: After testing parallel squat 1RM at a separate session, subjects performed three

    testing sessions in a randomized order in a cross-over design; performance test at 80% of

    parallel squat 1RM (control), one repetition at 85% of 1RM followed 8 minutes later by the

    same performance test (PAP85), and one repetition at 93% of 1RM followed 8 minutes later

    by the same performance test (PAP93). Sessions were separated by six days. Force and power

    output was recorded using a linear encoder. Friedman’s test was used to reveal differences

    between conditions, and a Wilcoxon signed rank test was used to identify these differences.

    Results: There was an increase in number of repetitions performed for PAP85 (p=0.009) and

    PAP93 (p=0.001) compared to control, but not for mean power or mean force. There was no

    significant difference between PAP85 and PAP93 for number of repetitions (p=0.091).

    Conclusion: PAP can be elicited to improve performance in moderately heavy squats

    following a heavy squat pre-load in trained subjects, but only measured as number of

    repetitions performed, not force or power. PAP could therefore be useful not only for

    designing power training, but also for strength and hypertrophy training.

    KEYWORDS: squat, post-activation potentiation, PAP, strength, power, hypertrophy.

  • 44.
    Björnell, Rebecha
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Kristensson, Michaela
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Kan ett 5-veckors hembaserat träningsprogram förbättra smärtan hos personer med fibromyalgi?2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Syftet med denna studie var att undersöka om ett 5-veckors enkelt styrketräningsprogram i hemmet minskar den upplevda smärtan hos personer med fibromyalgi.

    Metod: Antal deltagare med fibromyalgi var 10 stycken som rekryterades för att genomföra ett 5 veckors träningsprogram med fokus på styrka i buk-, rygg- och magmuskulatur. Före och efter träningsprogrammet mättes styrka (rygg, mage och ben – 3 tester) och smärta (Visual Analog Skala - VAS). Fyra frågor kring smärta besvarades med VAS-skala. Skillnad mellan undersökning före påbörjad träning (pretest) till undersökning efter avslutad träning (posttest) analyserades. Wilcoxons rangtest användes för att undersöka om där fanns en signifikant skillnad mellan pretest och posttest.

    Resultat: Efter avslutat träningsprogram hade inte smärtan förbättrats. I styrketesterna framkom signifikant förbättrad benstyrka medan rygg- och magstyrka var oförändrad. För sju av tio av deltagarna förbättrades styrkan i magtestet utan signifikant skillnad och för fem av tio deltagare förbättrades styrkan i ryggtestet utan signifikant skillnad. Smärtan var efter avslutad träning förbättrad, dock ej signifikant skillnad.  

    Slutsats: Det studerade styrketräningsprogrammet under 5 veckor ledde inte till en minskning av smärta.

  • 45.
    Blomgren, Bo
    et al.
    Safety Assessment, Bgn. 681 Gärtuna, AstraZeneca R and D Södertälje, Sodertalje SE 151 85, Sweden; Institution of Women's and Children's Health, Uppsala University, Uppsala, Sweden.
    Johannesson, Ulrika
    Division of Obstetrics and Gynaecology, Karolinska Institutet Danderyds Hospital, Stockholm, Sweden.
    Bohm-Starke, Nina
    Division of Obstetrics and Gynaecology, Karolinska Institutet Danderyds Hospital, Stockholm, Sweden.
    Falconer, Christian
    Division of Obstetrics and Gynaecology, Karolinska Institutet Danderyds Hospital, Stockholm, Sweden.
    Hilliges, Marita
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    A computerised, unbiased method for epithelial measurement2004In: Micron, ISSN 0968-4328, E-ISSN 1878-4291, Vol. 35, no 5, p. 319-329Article in journal (Refereed)
    Abstract [en]

    Objective

    To develop and evaluate a standardised method for unbiased measurements of epithelial thickness taking the variability of the dermal papillae in consideration.

    Methods

    A computer-assisted measurement program suitable for haematoxylin and eosin routine stained specimens has been developed.

    Results

    The developed program was designed to measure four different distance parameters, taking the number, height and width of dermal papillae into account. The measurement program gave very accurate results compared with manual measurements. The measurement results can be presented as tables or star graphs, and the results can be further processed by multivariate analysis.

    Conclusion

    The computer-assisted measurement program is considered to be a valuable and reliable tool for measurements of epithelial thickness, irrespectively of the variability of the epithelial morphology. Since length, size and number of the papillae may change with certain pathological conditions, age and also under hormonal influence, this method can be a helpful diagnostic tool.

  • 46.
    Bodin, Hristina
    et al.
    Linköping University, Linköping, Sweden.
    Mietto, Anna
    University of Padova, Legnaro, Italy.
    Ehde, Per Magnus
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Persson, Jesper
    Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Weisner, Stefan
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Tracer behaviour and analysis of hydraulics in experimental free water surface wetlands2012In: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 49, p. 201-211Article in journal (Refereed)
    Abstract [en]

    Effects of inlet design and vegetation type on tracer dynamics and hydraulic performance were investigated using lithium chloride in 18 experimental free water surface wetlands. The wetlands received similar water flow but had different vegetation types: 6 emergent vegetation wetlands (EVWs), 6 submerged vegetation wetlands (SVWs) and 6 free development wetlands (FDWs). Two types of inlet designs were applied: half of each wetland vegetation type had a barrier near the inlet to help distribute incoming tracer solution, while the rest had no barrier. Residence time distribution (RTD) functions were calculated from tracer data using two techniques: method of moments and a novel Gauss modelling approach. RTD functions were used to quantify hydraulic parameters: active wetland volume (e-value), water dispersion (N-value) and hydraulic efficiency (lambda-value). For wetlands without barrier, significantly lower tracer mass recoveries were found from EVWs compared to FDWs and SVWs, signifying a risk of tracer methodological problems in small densely vegetated wetlands. These problems were minimized in wetlands with an inflow construction promoting distribution of incoming tracer solution. Compared to the method of moments, Gauss modelling seemed to produce more reliable lambda-values but less reliable N-values. Data for precise hydraulic quantification were lost by Gauss modelling, as indicated by overall lower variance in these data sets and lower mass recoveries. However, Gauss modelling may minimize uncertainties associated with lithium immobilization/mobilization. Parameters were significantly affected by the RTD data analysis method, showing that the choice of method could affect evaluation of wetland hydraulics. The experimental wetlands in this study exhibited relatively high e-values and low N-values. This was probably caused by the small size of the wetlands and low water flow velocities, emphasizing that hydraulic parameter values obtained in small experimental wetlands may not be applicable to hydraulics in larger wetlands. The method of moments revealed lower e-values from EVWs compared to SVWs and FDWs. It was indicated that lower e-values were mainly caused by vegetation volumes. This highlighted a need for regular maintenance to secure efficient treatment volume in wetlands with dense vegetation. © 2012 Elsevier B.V.

  • 47.
    Bohman, Mattias
    et al.
    Grontmij AB.
    Berglund Odhner, Peter
    Grontmij AB.
    Schabbauer, Anna
    Grontmij AB.
    Karlsson, Niklas
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Mattsson, Marie
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Rundstedt, Johan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Biogas i Halland: Förbehandling av substrat och simulering av biogasflöden2011Report (Other academic)
    Abstract [sv]

    Bioenergicentrum i Halland (BEH) är ett projekt som ligger inom ramen för EU:s strukturfondsprogram. Projektet genomförs i Region Hallands regi som är regionens välfärds- och utvecklingsorganisation. Arbetet som bedrivs inom BEH syftar speciellt till att driva utvecklingen mot en ökad produktion och användning av bioenergi till biogas och i förlängningen fordonsgas. Genom att satsa på att skapa förutsättningar för innovation, kunskapsutveckling och samverkan främjas tillväxt och hållbar utveckling.

    Vid naturbruksgymnasiet i Plönninge utanför Halmstad finns idag en biogasanläggning som beskickas med bl.a. nötgödsel och matavfall. Dessutom finns en mindre pilotanläggning som är tänkt att fungera som en del av test- och verifieringsanläggning som BEH vill bygga upp i Plönninge. Som ett led i att utveckla dessa anläggningar och kunna erbjuda möjligheten till kunskapsinsamling genomfördes projektet som beskrivs i denna rapport. Uppdraget var att genomföra försöksrötningar på labb, använda resultaten för att skapa en modell som sedan kan nyttjas som ett verktyg i det inledande arbetet med att investera i en biogasanläggning som beskickas med lantbruksbaserade substrat. Högskolan i Halmstad (HH) genomförde försöksrötningarna och Grontmij (GM) använde sedan resultaten för att skapa en modell där bl.a. substrat, förbehandlingsteknik och driftkostnader finns med.

    Sammanfattningsvis kan sägas att majs som substrat fungerar bäst med de valda förbehandlingsmetoderna; kemisk behandling, termisk behandling och ultraljudsbehandling. Alla förbehandlingsmetoder med majs som substrat visade på ett positivt resultat, d.v.s. det ökade gasutbytet och dess värde (kr/kWh) översteg kostnaderna för de olika förbehandlingarna. Vad som måste beaktas är att produktionskostnaderna överlag är höga, med och utan förbehandling.

    Modellen har konstruerats på ett sådant sätt att den ska vara användarvänlig och med möjlighet att enkelt lägga till ytterligare substrat och förbehandlingsmetoder. Upprepningar av de försöksrötningar som genomförts kommer att öka tillförlitligheten hos modellen. Den fungerar som ett verktyg i att beräkna investeringsmarginalen för förbehandlingsutrustningen baserat på det valda substratet. På detta vis kan intressenter få en första indikation på om det är ekonomiskt rimligt att gå vidare med det tänkta substratet, den valda förbehandlingsmetoden, de planerade mängderna substrat etc.

    En investeringskalkyl har tagits fram för en gårdsanläggning som hanterar 5 000 ton substrat eller gödsel årligen. Det motsvarar 2-3 stycken medelstora mjölkgårdar. Kalkylen är översiktlig och syftar till att ge en första indikation på kostnader för de stora komponenterna såsom substratlager, rötkammare och rötrestlager. Kringarbeten såsom utredningar, markarbeten och geoundersökningar är inte med i kalkylen då dessa omkostnader till stor del avgörs av lokalisering och de förutsättningar som finns på platsen redan från start. Generellt kan dock sägas att den absolut billigaste och enklaste gårdsbaserade biogasanläggningen innebär en investering på 2,7-4 MSEK för flytgödsel från 100-300 mjölkkor.

    För BEH är det viktigt att skapa en plattform där intressenter kan komma för att genomföra försöksrötningar, byta erfarenheter och samla kunskap. För att uppnå detta är det nödvändigt att kunna erbjuda kunden kompletta och kompetenta lösningar på en och samma plats. Detta innebär ett erbjudande som innefattar försöksrötningar på labb-, pilot och fullskala. Ett förslag på konstruktion av pilotanläggning med övergripande principskiss ingår i denna rapport och fungerar som ett inledande arbete i projekteringen av en större pilotanläggning. Nödvändiga driftanalyser av rötrest ska kunna göras på plats i Plönninge på laboratoriet; analyser såsom enskilda organiska syror ska kunna skickas till lämpligt laboratorium. Personal ska kunna tillhandahållas för att driva och optimera rötningen enligt kundens syften och önskemål. På detta vis fungerar Region Halland som en länk mellan teori ochpraktik, mellan liten och stor skala och mellan aktörer från olika discipliner och geografiska områden.

  • 48.
    Bohm-Starke, Nina
    et al.
    Division of Obstetrics and Gynaecology, Karolinska Institutet Danderyd Hospital, Stockholm, Sweden.
    Johannesson, Ulrika
    Division of Obstetrics and Gynecology, Department of Clinical Sciences, Danderyd Hospital, Stockholm.
    Hilliges, Marita
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Rylander, Eva
    Division of Obstetrics and Gynecology, Department of Clinical Sciences, Danderyd Hospital, Stockholm.
    Torebjörk, Erik
    Dept. of Clinical Neurophysiology, University Hospital, Uppsala.
    Decreased mechanical pain threshold in the vestibular mucosa of women using oral contraceptives: a contributing factor in vulvar vestibulitis?2004In: Journal of reproductive medicine, ISSN 0024-7758, E-ISSN 1943-3565, Vol. 49, no 11, p. 888-892Article in journal (Refereed)
    Abstract [en]

    Objective:

    To analyze possible differences in somatosensory perception in the vestibular mucosa in healthy women associated with the use of oral contraceptives.

    Study design:

    Quantitative sensory tests were performed on the vestibular mucosa in 39 healthy women. Twenty women were using oral contraceptives containing 30-40 µg ethinyl estradiol combined with various progestins; 19 women with regular menstrual periods not using oral contraceptives served as controls. The testing included mechanical and heat pain thresholds and detection thresholds of warmth and cold in the anterior and posterior part of the vestibule.

    Results:

    Significant lower mechanical pain thresholds were observed in both areas tested in women using oral contraceptives. The most sensitive area was the posterior vestibule in the group using oral contraceptives with a mechanical pain threshold of 72±10 (±SEM) mN as compared to 161±3 mN (p<0.01), in the controls. The result of the thermotest showed no significant differences between the groups.

    Conclusion:

    Oral contraceptives may induce increased sensitivity in the vestibular mucosa in healthy women and might be one contributing factor in the development of vulvar vestibulitis.

  • 49.
    Borgström, Karin Margaretha
    et al.
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Distribution of heat use in Sweden2010Conference paper (Refereed)
    Abstract [en]

    The current heat use refers normally to the average heat use in a country or a sector during the course of a year. But it is also important to be aware of the distribution of high to low use when estimating the potential for reducing total heat use.Energy statistical data published in the annual report from Statistics Sweden have been supplemented by a deeper analysis of distribution of heat use and systematic causes regarding high heat use.The aim of this paper is to explain the variation in heat use with respect to construction year, degree days and energy efficiency measures.In the Swedish energy efficiency debate, many voices refer to systematic causes for high heat use. However, the results from this study do not support this opinion, since the use distribution mostly comes from individual causes. The most important implication of the study results is that systematic policy measures will have a low impact on the total national energy efficiency.

  • 50.
    Brandt, Sofie
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Hjälpmedel som underlättar öppnandet av skruvkorkar: - ett produktutvecklingsprojekt2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every day we encounter various types of packaging. For many people, the opening of these packages is a difficult task, since it requires a certain degree of hand strength to succeed. Reduced hand strength can be a result of injuries or diseases such as Parkinson's disease, finger-joint osteoarthritis and rheumatoid arthritis. Aging also has a negative effect on hand strength and function. An example of packaging that is difficult to open, is the ones with a plastic screw cap. Many packages, containing juice and milk products, as well as PET bottles, have this design. Today there are many tools in order to open these packages, but tests of existing facilities indicate that they do not meet user demands for functionality and usability. Therefore, the aim of the project was to develop a functional product that fits so many cap sizes as possible, and also be designed so that it can access the cap on all packaging.

    As part of the product development process, a group of women, 67-85 years old, who all experience difficulties in opening packaging with screw caps, was interviewed. Their views and opinions were of great importance for the project. Furthermore, brainstorming, sketching, prototyping and CAD modeling were methods used in the project. The CAD model was used to manufacture the product.

    The project resulted in a functioning product made of aluminum, and fits all cap sizes with a diameter of 25-41 mm, which includes all caps in today's packaging for juice and milk products, as well as PET bottles. The product is using a lever, which reduces the power consumption by up to 92%, and will facilitate the opening of packaging with screw caps for people with reduced hand strength.

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