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  • 451.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    European space cooling demands2016In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 110, p. 148-156Article in journal (Refereed)
    Abstract [en]

    Information about European space cooling demands is rare, since cooling demands are not properly measured, when electricity is used for operating space cooling devices. Cooling demands are only measured at deliveries from district cooling systems. However, information about cooling demands by location and country is required for planning district cooling systems and modelling national energy systems. In order to solve this cooling information dilemma, space cooling demands have been assessed for European service sector buildings. These estimations were based on cold deliveries from twenty different European district cooling locations in eight countries. Main findings are that (1) the estimated specific cold deliveries are somewhat lower than other estimations based on electricity inputs and assumed performance ratios, (2) aggregated spacecooling demands are presented by country, and (3) an European contour map is presented for average specific space cooling demands for service sector buildings. © 2015 Elsevier Ltd.

  • 452.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science. Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Fjärrvärmens framtida roll i Europa2017Report (Other academic)
  • 453.
    Werner, Sven
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Low carbon district heat in Sweden: District heat and cogeneration in Sweden2007In: Euroheat and Power - English edition, ISSN 1613-0200, Vol. 4, no 4, p. 20-25Article in journal (Refereed)
    Abstract [en]

    The development of the Swedish district heating sector with a market share of 54% in the heat market for buildings in the residential and service industry, is discussed. The district heat is generated using waste incineration, industrial surplus heat, biomass, and fossil combined heat and power (CHP). It reduces carbon dioxide emissions by 63 to 87% lower than in European cities and towns using natural gas and fuel oil to heat buildings. The district heat sector involves about 140 companies with 540 networks located in 220 municipalities. District heating systems have been started to obtain heat sinks for future municipal CHP plants. National energy policy program for reducing the oil dependence and carbon dioxide emissions has boosted the growth of the sector to meet the energy demand of buildings.

  • 454.
    Werner, Sven
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Lägre intäkter från högre fjärrvärmepriser?: en kortfattad analys utifrån fjärrvärmens priselasticitet2009Report (Other academic)
    Abstract [en]

    The long term price elasticity for district heating in Sweden has been estimated to -0,35 for the time period between 1970 and 2006. The implication of this estimation is that a Swedish district heating company can only keep 65 % of a real price increase. The remaining 35 % will disappear due to the energy efficiency measures initiated by the customers due to the price increase.In the total revenues, the price elasticity of district heating will be reinforced, if a combined heat and power plant is used in the heat supply. Then the revenues for generated electricity will also be reduced if the heat demand is reduced. In the defined reference case including a biomass combined heat and power plant, the final revenue elasticity became -0,51, almost 50% higher than the price elasticity estimated. If the combined heat and power is based on waste incineration, the reinforcement of the price elasticity is much lower. This result can be explained by the lower heat power share of combined heat and power in the district heating system, the low power-to-heat ratio and the somewhat lower remuneration for the electricity generated.One general conclusion from the analysis performed is that the Swedish district heating companies must consider the price elasticity of district heating in their long term planning. Another conclusion is that the companies must focus on cost reductions rather than price increases in order to preserve the current combined heat and power base for the future.

  • 455.
    Werner, Sven
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Andersson, Sofie
    FVB.
    Abrahamsson, Eva-Marie
    AKRAB.
    Fjärrvärmeolyckor: en översiktlig förstudie2009Report (Other academic)
    Abstract [en]

    This prestudy contains a short survey of both international and national information sources about district heating accidents. Also an own database with almost 200 district heating accidents has been analysed.

    Our main conclusions are:• The common denominators for accidents in heat generation are fires and explo-sions.• In heat distribiution, the common denominator seems to be pressure hammers.• It seems probable that district heating systems have lower risk for accidents withrespect to frequencies and consequences compared to other energy systems.• No person was killed or injured in the seven major district heating accidentsreported in the national register of large accidents.• To our knowledge, no customer or third person has been killed or injured by adistrict heating accident in Sweden. However, at least two employees have been killed from scalding of hot water.

    Our recommendations are:• We suggest a revision of the national standards concerning fires and explosions inorder to identify any possibilities to decrease the future frequencies in heat gene-ration plants.• We suggest that the demand for a national standard concerning pressure hammersin distrct heating systems should be considered.• We suggest a study in order to quantify the risks for district heating accidents ba-sed on actual accidents and compare them with the risks in other energy systems..

  • 456.
    Werner, Sven
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Ericsson, Karin
    Department of Technology and Society, Lund University, Lund, Sweden.
    Three decades of biomass use in Swedish district heating systems2015In: European Biomass Conference and Exhibition Proceedings, Florence: ETA-Florence Renewable Energies , 2015, p. 519-528Conference paper (Refereed)
    Abstract [en]

    More than two thirds of the heat supply to the Swedish district heating systems is nowadays based on biomass and waste resources. These district heating systems provide heat to cover more than half of the heat demands in the Swedish building stock. This paper reveals the development from the original use of fossil fuels in the late 1970s, the introduction of biomass as fuel in the early 1980s, the transition to considerable more renewables during the 1990s, and to the current situation when biomass dominates the heat supply. Our four conclusions consider the established infrastructure in both forestry and district heating, driving forces from energy policy tools and local initiatives, the contradiction between primary energy use of biomass and traditional heat recovery, and finally the future challenge of competitive use of biomass.

  • 457.
    Werner, Sven
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    Frederiksen, Svend
    Lunds Universitet.
    Fjärrvärme och fjärrkyla2014Book (Refereed)
    Abstract [sv]

    Effektiv förflyttning av värme och kyla i stadsområden är det huvudsakliga syftet med fjärrvärme- och fjärrkylesystem. Genom att koppla samman kundernas värme- och kylbehov med olika tillgängliga värme- och kylkällor kan man tillgodose behoven med ett totalt lägre resursutnyttjande än med konventionella värmepannor och luftkonditioneringsaggregat.

    Denna lärobok innehåller avsnitt om den grundläggande affärsidén, energimarknader, kundbehov, lastvariationer, värmetillförsel, miljöpåverkan, distribution, fjärrvärmecentraler, systemfunktion, ekonomi, planering, historisk utveckling, nutida oh framtida användning, organisation och informationskällor avseende flöden av värme och kyla i fjärrvärme- och fjärrkylesystem.

    Fjärrvärme och fjärrkyla är en tvärvetenskaplig teknik med element från många allmänna tekniker och metoder som förbränning, värmeöverföring, rörströmning, marknadsföring, fakturering etc. Vår uppgift har varit att ge grundläggande inledande kunskaper om typiska aspekter på fjärrvärme och fjärrkyla, vilka vi har bedömt vara viktiga för den grundläggande förståelsen eller mycket unika för denna nischteknik.

    Vi har haft ett brett spektrum av läsare i åtanke. Vår huvudsakliga målgrupp är fjärrvärmeingenjörer, universitetsstudenter, och anställda på fjärrvärmeföretag. Vi skulle också uppskatta om stadsplanerare, ekonomer, politiker och andra som är intresserade av ämnet kommer att tycka att den här boken ger konkret och användbar information om fjärrvärme och fjärrkyla.

  • 458.
    Werner, Sven
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Gong, Mei
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    District heating research in China2014Report (Other academic)
    Abstract [en]

    District heating is growing rapidly in China as Chinese building areas is expanding fast giving increased heating and cooling demands. This report gives an overview of the current situation for district heating and the research and development in this sector in China. Possibilities for collaboration between Swedish and Chinese researchers and companies in the field of district heating and cooling are also presented.

  • 459.
    Werner, Sven
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Lund, Henrik
    Aalborg University, Aalborg, Denmark.
    Vad Mathiesen, Brian
    Aalborg University, Aalborg, Denmark.
    Progress and results from the 4DH research centre2014In: Proceedings from the 14th International Symposium on District Heating and Cooling: September, 6-10, 2014: Stockholm, Sweden, Stockholm: Swedish District Heating Association , 2014, p. 302-307Conference paper (Refereed)
    Abstract [en]

    With lower and more flexible distribution temperatures, fourth generation district heating systems can utilize renewable energy sources, while meeting the requirements of low-energy buildings and energy conservation measures in the existing building stock. 4DH is an international strategic research centre located at Aalborg University, which develops 4th generation district heating technologies and systems (4GDH). This technology is fundamental to the implementation of the Danish objective of being fossil fuel-free by 2050 and the European 2020 goals. The research centre is working between 2012 and 2017, with The Danish Council for Strategic Research as main financier and the participating 31 Danish and international companies and universities as co-financiers. Thirteen PhD student projects constitute a vital part of the research centre. In 4GDH systems, synergies are created between three areas of district heating and cooling, which also sum up the work of the 4DH Centre: Grids and components; Production and system integration, and Planning and implementation. This paper presents an overview of the progress and results achieved after more than two years of work. This includes the basic definition paper, the two Heat Roadmap Europe pre-studies, annual conferences, additional demonstration projects, initiated European project proposals, an international PhD course based on the new international textbook, PhD student seminars, all PhD student subjects, and a list of major papers and articles written so far within the research centre.

  • 460.
    Werner, Sven
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Reidhav, Charlotte
    Chalmers University of Technology, Gothenburg, Sweden.
    Profitability of sparse district heating2008In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 85, no 9, p. 867-877Article in journal (Refereed)
    Abstract [en]

    The expansion of district heating into areas of low heat densities (heat sparse areas) constitutes a challenge due to the higher distribution costs. The profitability of sparse district heating has been analysed from actual investments in 74 areas with 3227 one-family houses connected to district heating between 2000 and 2004 in Göteborg, Sweden. The profitability was estimated from a probable price model, a typical marginal heat generation cost, and the investments from the actual connections made. The analysis identified factors as the linear heat density and heat sold per house explaining the main variations in profitability. The profitability analysis was concluded with a competition analysis. The main conclusion is that sparse district heating is possible when reaching low investment costs for the local distribution network and low marginal costs for the heat generation. In Sweden, the general competitiveness of sparse district heating is facilitated by the high consumption taxes for fuel oil, natural gas, and electricity. Hence, it should be more difficult to introduce sparse district heating in other countries with low energy taxes. © 2008.

  • 461.
    Wiborg, Irene
    et al.
    Knowledge Centre for Agriculture, Denmark.
    Sørensen Langvad, Anne Mette
    Knowledge Centre for Agriculture and Aarhus University, Denmark.
    Hansson, Anna
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Balskilde Stoltenborg, Trine
    Bridging the gaps between science, regulation and practice in water environment management2011In: Science for the environment - environment for society: Bridging the gap between scientists and practitioners in environmental science, Aarhus: Aarhus University , 2011, p. 31-31Conference paper (Other academic)
    Abstract [en]

    AQUARIUS is an interreg North Sea Programme project carried out by 15 partners from 6 countries (Norway, Sweden, Germany, Holland, Scotland, and Denmark) all dealing with the implementation of the Water Frame Directive. A primary objective of the project is to find ways for sustainable water environment management which by AQUARIUS is defined as management that in respect of the rules both leads to “good water environment”, enables continued viable agricultural production, and is cost efficient in the interest of society. AQUARIUS works from social-ecological management perspective emphasizing the intricate linkages between ecological and social systems and the interdependent relationships among humans, that are mediated through interactions with biophysical and non-human biological units. As a project AQUARIUS copies the presently ongoing struggle by all EU member countries to create a public participatory approach to water management planning and implementation such as is launched by the EU Water Water Frame directive. it does so by engaging central water authorities, representatives from agriculture including agricultural advisors as well as research institutions in carrying out localized pilot studies in 7 pilot areas. Drawing on localized experiments with and locally founded experiences with different measures the project derives recommendations that may contribute to an EU policy approach. The special session aims at discussing the preliminary findings of the ongoing project. It includes the presentation of a heuristic tool consisting of relevant considerations to beware of when engaging in stakeholder collaboration on specific measurements whilst acknowledging the farmer as the central water management practitioner. The session also discusses some of the different pilot approaches to bridging the gaps between science, regulation and practice i.e. the concrete challenges faced by the approaches in trying to create outcomes that are mutually beneficial to various stakeholder interests. How can different stakeholders challenges be solved in cooperation creating a win-win situation for all? How can stakeholders (landowners) willingness to participate increase by seeing them as professional providers of eco-system services? When do stakeholders’ overlapping interests allow for collaborative action and when do they hinder it? These questions are among the issues to be addressed. One legal recommendation that may be derived from project experiences is a need to further to take the precautionary principle in public administration into account. In order to make sustainable solutions in an ever changing complexity, authorities need to make room for dynamic collaboration between science and practice.

  • 462.
    Widenfalk, Anneli
    et al.
    Department of Environmental Assessment, Swedish University of Agricultural Sciences, P.O. Box 7050, SE-750 07 Uppsala, Sweden.
    Svensson, Jonas M.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Goedkoop, Willem
    Department of Environmental Assessment, Swedish University of Agricultural Sciences, P.O. Box 7050, SE-750 07 Uppsala, Sweden.
    Effects of the pesticides captan, deltamethrin, isoproturon, and pirimicarb on the microbial community of a freshwater sediment2004In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 23, no 8, p. 1920-1927Article in journal (Refereed)
    Abstract [en]

    In three microcosm experiments, we exposed microbial communities of a natural sediment to environmentally relevant concentrations of the fungicide captan, the herbicide isoproturon, and the insecticides deltamethrin and pirimicarb. Exposure concentrations were estimated negligible concentrations (NCs), maximum permissible concentrations (MPCs), and 100 times MPC (100MPC). Experimental endpoints were microbial community respiration and biomass, bacterial activity, and denitrification. All four pesticides inhibited bacterial activity by 20 to 24% at MPC, which corresponded to concentrations in the range of μg/kg dry-weight sediment. Treatments with deltamethrin and isoproturon showed inhibiting effects on bacterial activity at NC exposures. Surprisingly, for captan, deltamethrin, and isoproturon, this inhibiting effect was not observed at 100MPC treatments. Microbial biomass was negatively effected in MPC treatments with deltamethrin and in NC treatments with isoproturon. The tested pesticides did not affect community respiration and denitrification rates. These results show that exposure to the tested pesticides may induce toxic responses in sediment microbial communities at concentrations that are predicted to be environmentally safe.

  • 463.
    Wigroth, Caroline
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Mleczkovicz, Michel
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Hur omsätts protein och fett vid styrketräning?: Vilka fördelar och nackdelar kan en protein- och fettrik kost ha?2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med den här litteraturstudien var att undersöka effekten av hög protein- och fettrik kost på styrketräning. De flesta dagliga matvaror innehåller oftast både protein och fett förutom rena kolhydratkällor, vilka har olika effekt på kroppen vid styrketräning. Styrketräning kan påverka proteinsyntesen, muskelhypertrofi, lipolys och fettoxidationen i kroppen. Dessa processer influeras av mängden protein eller fett som konsumeras, vilken typ av protein eller fett som konsumeras samt tidpunkten intaget sker i relation till styrketräning.Studier har visat att ett högt proteinintag i kombination med styrketräning kan leda till ökad muskelmassa och viktnedgång på grund av en ökad proteinsyntes, lipolys och fettoxidation. Tidigare forskning visar också att ett ökat fettintag stimulerar lipolys och fettoxidationen hos individer. Ett ökat intag av protein och fett kan också ha negativa effekter på kroppen vid överkonsumtion. Ett ökat intag av proteinkällor som innehåller stora mängder fett kan leda till flera negativa effekter så som njursvikt, förhöjt blodtryck, kalciumbrist, skelettnedbrytning, kardiovaskulära sjukdomar och ökad fettinlagring.Slutsatsen är att mängden protein och fett som konsumeras kan leda till flera olika effekter vid styrketräning och kan anpassas till individens egna mål.

  • 464.
    Wikander, Robert
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Augustsson, Johan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Kan ett nyutvecklat handledsstöd förbättra möjligheterna för funktionell träning av övre extremiteten för reumatiker?: En SEMG-studie2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a general rehabilitation phase weight training is an important part because of muscle weakness may contribute lower functional ability and could lead to decreasing movement patterns. Limited range of motion (ROM) in the upper extremity is a contributing factor to individuals unable to perform everyday activities. Several studies have documented that patients with rheumatoid arthritis (RA) have impaired hand function due to reduced grip strength and limitations in ROM. Functional training is designed to strengthen the weak muscles that cause imbalance or pain while your body becomes more mobile. Using everyday movements and implement them with training will make the training more functional. The purpose of this study was to develop and evaluate a new wrist support that increases the possibilities to functional training of upper extremities for rheumatoid arthritis patients.

    The study involved 27 women, 8 were diagnosed with RA and 19 healthy subjects. The average age was 38 year (20-73year). Muscle activity in m. trapezius and m. rhomboideus was measured using surface electromyography (sEMG) in three exercises to compare the differences between both RA and healthy, and with and without a developed product.

    The results showed that it was possible to perform functional training of upper extremities without using the hand grip strength. There were no significant differences in muscle activity in m. trapezius and m. rhomboideii with or without the product. The results also showed that rheumatic muscles are not different from healthy muscles. The participants' subjective opinions were very positive there 24 of 27 participants found it easier to carry out the exercise

    with the product and 9 of 27 felt it was easier to focus on exercise.

    The study resulted in a new wrist support that allows functional training of m.trapezius and m.rhomboideus for patients with rheumatoid arthritis.

  • 465.
    Wiltshire, Robin
    et al.
    Building Research Establishment (BRE), Watford, United Kingdom.
    Williams, Jonathan
    Building Research Establishment (BRE), Watford, United Kingdom.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    European DHC Research Issues2008Conference paper (Refereed)
    Abstract [en]

    Euroheat & Power is now working towards a European Technology Platform for District Heating and Cooling. In response to this important European DHC research initiative, a preliminary detailed list of research issues within 18 dimensions was elaborated and communicated to more than 100 people in February 2008. After additions and comments received, an updated list of research issues was again distributed in July 2008. This paper contains the current list of suggested research issues.

  • 466.
    Winqvist, Jacob
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Grenzdörfer, Christopher
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Driver Club Head Speed Correlates to Rotational Power in Competitive Amateur High School Golfers: Bachelor of Science Thesis 15hp2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: As a sport Golf is known for its power and precision regarding the swing. The swing that produces the most power is the drive. The club head speed (CHS) of the drive is a commonly used measurement of swing performance. Studies have shown a strong correlation between CHS and rotational power of the trunk musculature. Up until this year the gold standard for measuring rotational power of the trunk has been the medicine ball side throw (MBST). In 2012 a study investigating the rotational power in the trunk measured by a seated cable torso rotation (SCTR) was published. For this thesis, the authors hypothesized that the SCTR would have a higher correlation to CHS than MBST. Method: A correlation study design was used to examine the relationship between CHS, SCTR and MBST. 20 healthy competitive amateur high school golfers (n=20 - 17 male, 3 female, age 17 ±1.2, weight 73 ±12 kg, height 180 ±9 cm, handicap 6,6 ±2,4) were recruited. Results: Significant correlations were found between; CHS and MBST (r=0,79 p=0,01); CHS and SCTR (r=0,80 p=0,01, r=0,80 p=0,01). MBST and SCTR also significantly correlated with ball speed. Discussion: Results did not confirm the authors’ hypothesis, although both tests proved to be significantly correlated to CHS. This shows that both tests seem to be equally effective when testing rotational power in competitive high school golfers, although the MBST seems to be more efficient.

  • 467.
    Wittwer, Torben
    et al.
    Department of Earth and Ecosystem Sciences, Lund University.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Suhling, Frank
    Institut für Geoökologie, Technische Universität Braunschweig, Braunschweig, Germany.
    Does one community shape the other?: Dragonflies and fish in Swedish lakes2010In: Insect Conservation and Diversity, ISSN 1752-458x, Vol. 3, no 2, p. 124-133Article in journal (Refereed)
    Abstract [en]

    1. Freshwater communities are often structured by predation. In permanent lentic freshwater habitats dragonfly larvae aremajor predators which, in return, suffer predation by fish. Antipredator traits vary between the dragonfly species, and the dragonfly communities are therefore shaped by the presence of fish. But fish communities vary, and as different fish species affect dragonflies in different ways, the species composition of the fish community may affect the composition of the dragonfly community.

    2. We sampled dragonfly larvae in 24 lakes with a known fish stock in south-western Sweden, and explored the impact of fish as well as vegetation structure on dragonfly communities by means of multivariate analyses.

    3. We found that the presence of four fish species affected the community structure of dragonflies. The impact strength depended mainly on the abundance of Perca fluviatilis, with which most dragonfly species were negatively correlated. Many dragonfly species were also positively correlated with the occurrence of at least one fish species, which may reflect similar habitat requirements or imply indirect positive effects of these fish species.

    4. Of the 24 recorded dragonfly species, four did not occur in lakes dominated by P. fluviatilis, whereas only one species was lacking in lakes dominated by Rutilus rutilus. The dragonfly species diversity was higher in R. rutilus lakes than in P. fluviatilis lakes.

    5. Our results suggest that the fish species composition is a major determinant of the dragonfly community, which in turn will influence the lower trophic levels.

     

     

  • 468.
    Woin, Per
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Aquatic ecosystems - Reports of the breakout groups2005In: Effects of Pesticides in the Field / [ed] M. Liess, C. Brown, P. Dohmen, Brussels: Society of Environmental Toxicology and Chemistry (SETAC), 2005, p. 113-123Chapter in book (Other (popular science, discussion, etc.))
    Abstract [en]

    Information in this book was obtained from individual experts and highly regarded sources. It is the publisher’s intent to print accurate and reliable information, and numerous references are cited; however, the authors, editors, and publisher can not be responsible for the validity of all information presented here or for the consequences of its use. Information contained herein does not necessarily reflect the policy or views of the Society of Environmental Toxicology and Chemistry. This book presents the proceedings of a SETAC Workshop convened by the Society of Environmental Toxicology and Chemistry (SETAC) and the European Union in Le Croisic, France, in October 2003. The 77 scientists involved in this workshop represented 17 countries from Europe, the United States and Canada and offered expertise in ecology, ecotoxicology, environmental regulation, and risk assessment.

  • 469.
    Yang, Fan
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Mesophilic anaerobic digestion conducted in single unit reactor at increasing ammonia concentrations2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of mesophilic anaerobic digestion for treatment of organic wastes is a growing biotechnology for sustainable energy supply. Ammonia inhibition is a major problem in anaerobic digestion mainly when digestion of nitrogen-rich substrates such as livestock wastes and manure occurs. This paper provides a summary of research conducted on ammonia inhibition of the anaerobic process. An experiment with mesophilic digestions of swine manure was conducted in single unit reactors, which were controlled under different ammonia concentrations by addition of NH4Cl in different amounts. From the experimental results, it was shown that NH4Cl could be an effective chemical agent for removing foam and scum in the digester. Methane production was decreased with the increasing NH4Cl addition until a collapse was observed between 11.2 g NH4+-N/l and 13.2 g NH4+-N/l. Contrary to the findings in thermophilic digestion, a dysfunction of acidogenesis was also observed since both gas and methane production was delayed with increasing NH4Cl addition. These findings suggest different ammonia inhibition principles in mesophilic and thermophilic digestion. It was further indicated that methanogenesis could produce a high percentage of methane although gas production was inhibited.

  • 470.
    Åhlund, Anton
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science. Halmstad University.
    Solar Cooling: -A study of two thermal systems2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Electricity-driven air-conditioning is energy-intensive and puts a strain to many grids during hot periods in warm climates. Solar thermal cooling could be an alternative to conventional cooling, using a renewable energy source and supplying the most energy during peak demand periods with insignificant effect to the electric grid.

    Office buildings in warm climates have high cooling loads, naturally peaking during daytime because of occupancy and ambient temperature. Thus, office buildings have a seemingly advantageous relationship between the possible supply of solar thermal energy and cooling demand. With this background, solar cooling systems for two office buildings with the same dimensions are investigated, placed in a tropical- and a sub-tropical location.

    There are great differences in the design conditions for solar cooling systems in the tropics and the sub-tropics, between the chosen locations Manila and Abu Dhabi more specifically.

    Manila has a quite evenly distributed cooling load while Abu Dhabi has a strongly pronounced summer season with very high maximum cooling loads, while the winter temperatures are relatively low. The prior described conditions creates a big difference between loads throughout the year, making a thermal chiller less effective in this aspect. However Abu Dhabi is expected to have an overall smoother- and ultimately a more high performance solar cooling system due to lower humidity, which facilitates the important cooling of the chiller.

    Evacuated tube collectors were used at both sites, where the collectors in Manila needs to be larger relative to the chiller cooling capacity, in order to compensate for the irregularity of direct solar radiation.

    The electricity price in Abu Dhabi is too low for the solar cooling system to be economically feasible compared to a conventional system, where the net values over 20 years are 163 000 € and 127 000 €, respectively. Manila has on its hand a very high price for electricity, making the 20-year net values for both the solar cooling- and the conventional system approximately 170 000 €.

  • 471.
    Årneby, Henrik
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    The acute effect of a foam rolling and a dynamic stretch warm-up routine on jumping performance2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Self-myofascial release is widely used by athletes but the scientific evidence of its supposedly positive effects is limited. This study was conducted to investigate the effects of foam rolling as a warm-up routine in comparison with a dynamic stretching routine and how it may affect the jumping performance among subjects familiar with weight training. Aim: The aim of this study was to investigate the acute effect of foam rolling vs. a standardized dynamic stretch warm-up routine on jumping performance. Method: Twelve subjects, mean (SD) age 25.1 (± 3.0) years, participated in a randomized, controlled, crossover study. All subjects completed a standardized foam rolling (FR) and a dynamic stretch (DS) warm-up routine on separate days of testing. Squat jump (SJ), counter movement jump (CMJ) and loaded counter movement jump (L-CMJ) all performed bilaterally and unilaterally were conducted to investigate the acute effect of the two warm-up routines. A dependent T-test was used to investigate differences between the warm-up routines. Results: A statistical significant difference in favor of the DS was found for SJ performed bilaterally among males (p = 0.009). The mean (SD) jumping height for SJ FR was 35.6 (± 4.7) cm and for SJ DS 37.9 (± 5.2) cm. The male group also improved more in L-CMJ performed on the right leg with an external load of 54kg after DS compared to FR. No other statistical significant differences were found between the two interventions. A near statistical significant difference was found for SJ performed bilaterally for the total sample (p = 0.057) also in favor of the DS. The mean (SD) jumping height for SJ FR was 29.3 (± 8.7) cm and for SJ DS 30.5 (± 9.9) cm. Conclusion: Findings from this study supports a dynamic stretch warm-up routine prior to performing high intensity bilateral plyometrics instead of a foam rolling warm-up routine. However the data was inconsistent and more research with larger sample sizes is needed to further investigate the possible effects of foam rolling as a warm-up routine on jumping performance performed both bilaterally and unilaterally.

  • 472.
    Åström, Sara
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Jorlöv, Josefine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Karaktärisering av solcellsmoduler: en fördjupning i solcellsteknik och metoder för karaktärisering2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sveriges Tekniska Forskningsinstitut, SP, has recently invested in a pulsed solar simulator to measure and characterize photovoltaic modules. The following report investigates the differences in the analysis between the new solar simulator and SP's existing pulsed solar simulator. All measurements have been performed on four different solar modules, two solar modules of type CIS and two solar modules of type crystalline silicon. We have also carried out practical measurements to see which environmental factors that affect the analysis from the new solar simulator. The surrounding factors consisted of ambient lighting, reflections from the new solar simulator and soiling of the monitor cell. The results show a difference between the quantified values of the new and existing solar simulator, where most of the measurements in the existing solar simulator are higher. The differences are probably due to measurements being made at a higher irradiance level than according to the standard. Furthermore, the results show that there are environmental factors affecting the analysis from the new solar simulator; a soiled monitor cell have the greatest influence on the outcome. 

  • 473.
    Özdes, Denise Seher
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Utfasning av miljö- och hälsofarliga kemikalieprodukter för att uppnå miljömålet "Giftfri miljö": Ett exempel från vård- och äldreomsorgsförvaltningen i Alingsås kommun2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Jag har valt att göra ett examensarbete för Alingsås kommun som går ut på att ta reda på vilka kemiska produkter som används inom vård och äldreomsorgen i Alingsås kommun samt komma med förslag och arbetsätt för Alingsås kommun att arbeta mer effektivt med deras utfasningsarbete. Genom att genomföra en litteratursammanställning av miljölagstiftningen, inventera kemikalie produkter som används i äldreboendena samt genomföra intervjuer om andra kommuners kemikaliearbete kan syftet med uppsatsen uppnås. Uppsatsen är en del av arbetet för att uppnå en del av Alingsås miljömål. Arbetet inleddes med en kemikalieinventering för samtliga äldre boenden där alla påträffbara rengöringsprodukter sammanställdes. De kemikalieprodukter som påträffades var rengöringsmedel för olika användningsområden. De rengöringsprodukter som inte var miljömärkta listades i en enskild lista och undersöktes. Meningen med undersökningen var att garantera att inga ämnen i produkterna var särskilt farliga för människors hälsa- och miljö. Resultatet av intervjuerna visade att det skiljer sig mellan olika kommuners kemikaliearbete men svaren visade också att alla kommuner arbetar med någon del som berör kemikaliearbetet men på olika nivåer. Litteraturstudien visar att miljömärkta produkter måste uppfylla en del krav för att bli miljömärkta, genom att använda sig av miljömärkta produkter bidrar man till att minska användingen av skadliga kemiska ämnen som påverkar miljö- och hälsa. Alingsås äldreboenden använder sig inte av några farliga rengöringsprodukter men en del av produkterna är inte miljömärkta som de borde vara enligt kommunens miljöpolicy och borde därför ersättas. Jämförelsevis utifrån de intervjuade kommunerna samt Alingsås kommun ligger Alingsås kommun på en bra nivå i sitt kemikaliearbete. En del bitar behöver utvecklas och med hjälp av enkla metoder kan man skapa ett bättre kemikaliearbete.

  • 474.
    Ørstavik, Kristin
    et al.
    Faculty of Medicine, University of Oslo.
    Namer, Barbara
    Department of Physiology and Experimental Pathophysiology, University of Erlangen/Nürnberg.
    Schmidt, Roland
    Department of Clinical Neurophysiology, University Hospital, Uppsala, Sweden.
    Schmelz, Martin
    Department of Anesthesiology Mannheim, University Heidelberg, Mannheim, Germany,.
    Hilliges, Marita
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Weidner, Christian
    Department of Physiology and Experimental Pathophysiology, University of Erlangen/Nürnberg.
    Carr, Richard W.
    Department of Physiology and Experimental Pathophysiology, University of Erlangen/Nürnberg.
    Handwerker, Hermann
    Department of Physiology and Experimental Pathophysiology, University of Erlangen/Nürnberg.
    Jørum, Ellen
    Laboratory of Clinical Neurophysiology, Department of Neurology, Rikshospitalet-Radiumhospitalet Medical Center, Oslo, Norway.
    Torebjörk, H. Erik
    Department of Clinical Neurophysiology, University Hospital, Uppsala, Sweden.
    Abnormal Function of C-Fibers in Patients with Diabetic Neuropathy2006In: Journal of Neuroscience, ISSN 0270-6474, E-ISSN 1529-2401, Vol. 26, no 44, p. 11287-11294Article in journal (Refereed)
    Abstract [en]

    The mechanisms underlying the development of painful and nonpainful neuropathy associated with diabetes mellitus are unclear. We have obtained microneurographic recordings from unmyelinated fibers in eight patients with diabetes mellitus, five with painful neuropathy, and three with neuropathy without pain. All eight patients had large-fiber neuropathy, and seven patients had pathological thermal thresholds in their feet, indicating the involvement of small-caliber nerve fibers. A total of 163 C-fibers were recorded at knee level from the common peroneal nerve in the patients (36–67 years old), and these were compared with 77 C-fibers from healthy controls (41–64 years old). The ratio of mechano-responsive to mechano-insensitive nociceptors was ~2:1 in the healthy controls, whereas in the patients, it was 1:2. In patients, a fairly large percentage of characterized fibers (12.5% in nonpainful and 18.9% in painful neuropathy) resembled mechano-responsive nociceptors that had lost their mechanical and heat responsiveness. Such fibers were rarely encountered in age-matched controls (3.2%). Afferent fibers with spontaneous activity or mechanical sensitization were found in both patient groups. We conclude that small-fiber neuropathy in diabetes affects receptive properties of nociceptors that leads to an impairment of mechano-responsive nociceptors. Copyright © 2006 Society for Neuroscience

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