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  • 1.
    Abbas, Taimoor
    et al.
    Lund Univ, Elect & Informat Technol Dept, S-22100 Lund, Sweden..
    Sjöberg, Katrin
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Kåredal, Johan
    Lund Univ, Elect & Informat Technol Dept, S-22100 Lund, Sweden..
    Tufvesson, Fredrik
    Lund Univ, Elect & Informat Technol Dept, S-22100 Lund, Sweden..
    A Measurement Based Shadow Fading Model for Vehicle-to-Vehicle Network Simulations2015In: International Journal of Antennas and Propagation, ISSN 1687-5869, E-ISSN 1687-5877, article id 190607Article in journal (Refereed)
    Abstract [en]

    The vehicle-to-vehicle (V2V) propagation channel has significant implications on the design and performance of novel communication protocols for vehicular ad hoc networks (VANETs). Extensive research efforts have been made to develop V2V channel models to be implemented in advanced VANET system simulators for performance evaluation. The impact of shadowing caused by other vehicles has, however, largely been neglected in most of the models, as well as in the system simulations. In this paper we present a shadow fading model targeting system simulations based on real measurements performed in urban and highway scenarios. The measurement data is separated into three categories, line-of-sight (LOS), obstructed line-of-sight (OLOS) by vehicles, and non-line-of-sight due to buildings, with the help of video information recorded during the measurements. It is observed that vehicles obstructing the LOS induce an additional average attenuation of about 10 dB in the received signal power. An approach to incorporate the LOS/OLOS model into existing VANET simulators is also provided. Finally, system level VANET simulation results are presented, showing the difference between the LOS/OLOS model and a channel model based on Nakagami-m fading.

  • 2.
    Abdou Mahmoud, Amir
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Dahlqvist, Ted
    Halmstad University, School of Business and Engineering (SET).
    Ånghuvud för steamer2010Independent thesis Advanced level (degree of Master (Two Years)), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The following report is for CAD-technicians 2nd year.

     

    The task that the report is built on is done in collaboration with Hafa AB. The task is to develop a new steam nozzle for steamers, a sort of combination of steam sauna and a shower. The reasoning behind the development is to make the steam nozzle match with Hafa’s current design and to gain as little wasted water as possible.

     

    There came forth a mutual idea to integrate the steam nozzle into the shower column, during a meeting with Hafa, which we developed further and became the first prototype.

     

    The prototype showed to be a success, even though protection for the steam had to be made since it flowed into the steamer at a rate which was not acceptable, mainly because little water was wasted and because the prototype was just a third of the original steam nozzle’s size.

     

    The method that we used was the same that was used by us during earlier courses in the CAD-technicians programme.

  • 3.
    Abebe, Abay Damte
    et al.
    Halmstad University, School of Business, Engineering and Science.
    He, Qikang
    Halmstad University, School of Business, Engineering and Science.
    Foam Behavior Analysis Based On A Force Measurement System2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    In the world where every sector of industrial manufacturing is being converted toautomated systems, surface finishing processes like sanding and polishing seem to lag.This phenomenon is not surprising as these processes are complex to optimize. Therehave been projects going on with the support of European Commission to findsolutions under SYMPLEXITY (Symbiotic Human-Robot Solutions for ComplexSurface Finishing Operations). One of the projects in under this include poliMATIC(Automated Polishing for the European Tooling Industry). Halmstad University isinvolved in doing projects.

    This project took a portion of this study in aim to understand a foam material’s behavior used for sanding tool at the tip of a robotic arm. This is studied using a forcemeasurement system developed at Halmstad University. The project has two sectionsand starts with one; Understanding the force measurement system and upgrading innecessary ways. Two; studying how the foam material compressive hardness propertyis affected when the material is fit with sandpaper for sanding operation using theforce measurement system. The study finally revealed how the combination of thefoam with sandpaper affects the robustness of the material, and significantlyimproved the output of the system with by reducing the noise level with 40%.

  • 4.
    Achampong, Davis
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Eriksson, John
    Halmstad University, School of Business, Engineering and Science.
    Purus Velox: En mekanisk städmaskin2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One of the park and street workers many tools, is the traditional broom. The

    broom is used to tidy up surfaces where machines can’t reach, such as; underneath

    benches, in corners and smaller areas. Using a traditional broom requires a twisted

    and forward leaning body posture that, if performed during an extended time

    period, can result in musculoskeletal problems and negative impact on the health.

    This project aimed to develop a new cleaning tool to reduce the forward-leaning,

    twisted body posture.

    This thesis used a product development methodology and a biomechanical

    analysis to fulfil, and evidence base the aim. Review of the literature,

    biomechanical analysis and benchmarking were used to set requirement

    specifications for this project. The project applied David G Ullman's iterative

    product development methodology, including brainstorming, quality function

    deployment, morphology, Pugh´s matrix and a failure mode effects analysis.

    Furthermore, a functional prototype was built as a last step of the development

    phase.

    Evaluation of the prototype, in comparison to the traditional broom, was

    performed using 3D movement analysis (Qualisys motion capture system) and

    surface electromyography (Mega 8 channel system) on one test person.

    The project resulted in a physically functional prototype that can be used for

    similar tasks as a traditional broom. The concept design dictates the user to push

    the cleaning tool in front of the body with postural symmetry in all three planes.

    The comparison between a traditional broom and the prototype showed a

    reduction in muscle activity when using the prototype. Furthermore, the

    movement analysis showed a working posture with less forward leaning and back

    rotation. Furthermore, the participant could keep neutral angles in the shoulders

    and wrists throughout the task. Note that, the biomechanical analyzes was only

    made on one test person which is not enough to conclude that the prototype

    contributes to a more healthy working posture.

  • 5.
    Adolfsson, Matilda
    Halmstad University, School of Business, Engineering and Science.
    Vibrationer och engesvängningar i Alfdex separator2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to create a greater understanding of what happens inAlfdex’s separator in terms of natural frequencies, also called resonances. Try in asystematic way to find out where the problem is and produce a possible solutionto the problem. To achieve this smoothly, vibration measurements were made onthree different models with two variants, a total of six different variants. Themeasurements made with an electric shaker were set to run a sweep of 2-500Hz,which means that it increases the frequency from 20-500Hz with a constantacceleration of 2G. The measurement was first made on these six variants and, onthe basis of the results, it has been possible to compare with the modificationsmade.As the first modification, the disks in the separator were glued together to see ifthey made any difference from the previous result. As the next test spacers wereprinted out of the 3D-printer, that would replace the existing springs in theseparator, to aww what happens if we do not have any springs. There was also atest where the top of the separator the so-called house, was cut into a larger holeso as to see how the disks hold a constant amplitude relative to each other, whichmeans that the disks are not exposed to any natural frequencies. The springs werefilmed to see how they act and move, where it is clear that there are naturalfrequencies in the springs.Based on these tests, it can be concluded that the disk in question are not aproblem. The problem instead has its foundation in the springs that carry the diskstack throughout the separator, resonances in these give a great influence in theentire contents of the separator.

  • 6.
    Akhtar, Naeem
    Halmstad University, School of Business, Engineering and Science.
    Analysis of Simris Hybrid Energy System Design and Working and Checking the Effects of Using High Capacity Factor Wind Turbine2019Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The world is entering the future where integration of renewable energy sources within the power grid will play an important role when facing the challenge of reducing global warming. The intermittent generation characteristics associate with renewable energy sources can be handled by the implementation of microgrids. A Microgrid is a group of energy source (e.g. wind, solar etc) that are located in the same local area that can operate independently in the event of electricity outage and can also be connected to the national grid in case of energy demand exceeds than the energy produced in the same local area. The implementation of microgrid in an electrical distribution system must be well planned to avoid problems. The EU has set high goals to reduce the non-renewable energy sources by 2030. EU has started some local energy systems (microgrids) and Simris is a part of it.

    This study is about a microgrid project at Simris in the south-east of Sweden. The village of Simris has 140 households supplied by a wind turbine of rated power 500kW and a solar power plant of 440 kW rated power. This project is run by E. ON within the framework and collaboration of Interflux, in which several network operators within the EU participate to investigate flexibility options in local energy systems. 

    The aim of this study is to find different scenarios in which the Simris microgrid can be run in islanded-mode. Four different scenarios were investigated, and simulation was done in MATLab. After simulation the results were discussed in the “Analysis and Results” section and the size of the wind turbine, the solar park (PV)and the battery were suggested for each of the scenarios. A short calculation was also included between the installation cost of the suggested wind turbine and the needed battery size. The cost of battery is much higher than the cost of wind turbine, so its beneficial for the economy of the microgrid to have a wind turbine of 1000 kW rated power and battery size 35 MWh rather than using the same old wind turbine of 469 kW rated power and upgrade the battery to 462 MWh. 

  • 7.
    Al Shalabi, Ammar
    et al.
    Multimedia University, Melaka, Malaysia.
    Omar, Mohammed K.
    Multimedia University, Melaka, Malaysia.
    Rundquist, Jonas
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Centre for Technology, Innovation and Marketing Management (CTIM2).
    Processes and strategies of NPD: A survey of Malaysian Industry2008In: International Journal of Manufacturing Science and Technology, ISSN 1524-1548, Vol. 10, no 1, p. 91-95Article in journal (Refereed)
    Abstract [en]

    In recent years, there has been a considerable interest in Malaysian manufacturing firms in New Product Development (NPD) which is considered to be indirectly a booster for the success of a firm. The purpose of the study is to highlight the NPD processes and methods used in Malaysian industry. This paper focuses only on the formal NPD-processes and NPD-strategies. From the available database, it is found that there are 250 confirmed companies from automotive, chemical, and electrical industries, which have R&D facilities; out of which 36% have agreed to participate in the survey, and 29% questionnaires have been used. The results show that the best firms have their R&D and NPD departments either overseas or partially in Malaysia.

  • 8. Albazi, Waleed
    Smart Student Table2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this study is to develop what is called aStudent table, which is designed specifically for school children in emergency circumstances, so it will be suitable for partial solutions for the problems facing children in refugee camps, who are forced to leave their homes and schools. The idea of the study focuses on the creation of the Student table so that the generation of electricity will be suitable for lighting and illumination with the use of some electronic devices used in daily school needs like laptops, so the solar cell system will be connected to a small generator through a hybrid system. A fully functional prototype has been built as part of the study. When the system works through the hybrid route for lighting and illumination the solar system will generate the power needed and when the sun light disappears the Power can be generated by bike pedals. The generation of electricity by the hybrid system is considered as an effective and environmentally friendly option with economic benefits.

  • 9.
    Aldegård, Alexander
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Gapinski, William
    Halmstad University, School of Business, Engineering and Science.
    Metodjämförelse för fixturkonstruktion till prototyptillverkning2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis work is done in collaboration with Prodtex AB, which works to

    develop digital tools to facilitate the constructor´s work in virtual environments,

    for instance CAFD within CATIA V5. What the client wanted the project

    participants to perform was a comparison of the company's semi-automatic

    software for fixture design, and the traditional construction method with CATIA.

    The reason for the method comparison is because Prodtex AB requires data,

    which they can present to potential customers.

    The participants produced a method to enable the necessary components of the

    project, the method consisted of training in fixture design, fixture construction and

    work with the consulting company´s application. These elements have been

    essential for the comparison to be reliable. The main part of the assignment

    consisted of constructing units for the given fixture. The reason behind this is due

    to the necessity of a certain level of experience in fixture design, which is required

    to be able to assemble units with an accurate and efficient procedure.

    The method comparison generated data in terms of time in the measurement areas,

    input, design and export that the project participants analyzed and compiled in the

    result section. Based on the statistics, participants were able to find answers about

    which features the software made the most time savings of, and how abundant

    these were in relation to the traditional design method. A conclusion about when it

    was beneficial for a company to invest in the software was based on reasoning

    deduced from the outcome discussion.

  • 10.
    Alexander, Mattsson
    Halmstad University, School of Business, Engineering and Science.
    Engine stability: A study of the events occurring prior to thecombustion in a small two-stroke engine2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is a study conducted in collaboration with the engine performance group atHusqvarna AB. The study focuses on engine stability of smaller two stroke handheld enginesrunning on E10 (10% ethanol mixture in gasoline). The reason for the study is the new EUproposition that by 2020 all fuel must have 10 % renewable fuel content. To meet thisproposition Husqvarna has evaluated E10 and found that the engine stability of smaller twostroke engines are affected in a negative way by the fuel.The study focuses on events occurring prior to the combustion and mainly the carburetor. Theobjective for the thesis is to seek what contribution the events occurring prior to thecombustion have to the engine stability and find simple and implantable solution to improvethe stability with regards to the carburetor.The study has been conducted in three different work packages, system understanding to buildknowledge of how the carburetor operates, fault finding to seek potential attributes that canaffect the stability and fault mode analysis to seek why the attributes affect the stability.Furthermore, all the attributes found has been tested and validated on the engine to seek theircontribution to the stability.The conclusion made of the thesis is that with simple and implementable improvements of thecarburetor the engine stability could be increased with 40 %. A total of five differentattributes were found to affect the stability of the engine. Furthermore, a very detailedexplanation of how the carburetor operates and components inside the carburetor has beenestablished during the thesis.

  • 11. Allahham, Hammam
    Study of the application of LeanManufacturing techniques in the food industry2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 12.
    Altmann, Peter
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Kämpe, Oskar
    Halmstad University, School of Business and Engineering (SET).
    AN OPEN INNOVATION APPROACH TO THE RADICAL INNOVATION PROCESS: An Analysis of the Management of the Process of Radical Innovation in an Open Innovation Paradigm2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis amends some existing theoretical gaps and an overall lack of empirical studies regarding the ways R&D managers can use Open Innovation during the management of the radical innovation processes’ early development phase.Using existing theories, an interview guide and an analytical model was created. These were later used during the gathering and analysis of empirical data. Our sampling involves three of Sweden’s largest companies, representing three distinct industry fields. Interviews took place during April 2010, and all the interviewees were R&D managers with previous experience with Open Innovation and radical innovation.The results reveal that the managers do use Open Innovation when managing radical innovation, and point to both benefits and issues brought about by using Open Innovation during this process. The use of Open Innovation during the management of radical innovation can be divided into two main aspects; the actual extent to which it is used, and the ways the managers use it. Our results reveal that the extent varies from an early peak, an in between Open Innovation chasm and a final increase. Furthermore, our studies also show that the main ways the managers use OI are; exploitation and creation of revenue streams, knowledge leveraging and integration, and finally to create superior products using broad knowledge networks.

  • 13.
    Altmann, Peter
    et al.
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Centre for Technology, Innovation and Marketing Management (CTIM2).
    Rundquist, Jonas
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Centre for Technology, Innovation and Marketing Management (CTIM2).
    Florén, Henrik
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Centre for Technology, Innovation and Marketing Management (CTIM2).
    Sustained innovativeness and human resource management2011In: Research on Technology, Innovation and Marketing Management 2009-2011: Introducing the Research Area of Innovation Science / [ed] Sven-Åke Hörte, Halmstad: Högskolan i Halmstad , 2011, p. 21-35Chapter in book (Other academic)
    Abstract [en]

    Innovation is paramount to success. Over time firms must maintain their ability to innovate in order to maintain their competitive edge. In this paper we explore the role human resource management has in nurturing and enhancing the innovative capability of the firm. To explore HRM activities, functions and processes that enhance or impede innovativeness we conducted a literature review. Following this review, 10 propositions have been made that link HRM to both incremental and radical innovativeness respectively. Our results include suggestions for empirical studies to validate our propositions as well as some managerial implications.

  • 14.
    Amanda, Hugosson
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Carolina, Martinsson
    Halmstad University, School of Business and Engineering (SET).
    Konstruktion och design av duschredskap2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna rapport presenteras ett examensarbete som syftar till att ta fram idéer för en användarvänlig produkt, anpassad till dusch- och badrumsmiljöer som gör att äldre och funktionsnedsatta kan klara sig mer självständigt i hemmet. Arbetet har utförts tillsammans med uppdragsgivaren Jörgen Carlsson, produktchef på företaget Macro International AB (Macro) som tillverkar, utvecklar och säljer badrumslösningar med duschar och möbler. Examensarbetet har genomförts på Högskolan i Halmstad under våren 2014 och omfattar 15 högskolepoäng.

    Målet med projektet var att utifrån ett valt koncept utveckla en prototyp som passar till Macros nuvarande duschsortiment samt ta fram konstruktionsritningar för eventuell tillverkning av produkten. Produkten skulle vara lätt att montera för privatpersoner samt utstråla den känsla, enkelhet, personlighet och spänning som företaget strävar efter i alla sina produkter.

    Arbetet inleddes med en omfattande marknadsundersökning där tolkningen och resultatet av undersökningen tillsammans med uppdragsgivarens åsikter ledde till ett antal idéer att gå vidare med och utveckla. Två designmetodiker har kombinerats med en konstruktionsmetodik vilket har lett till ett slutligt resultat av ett duschredskap som kan användas som stöd i Macros duschar ”Skagen” och ”Fjord”. En prototyp av produkten tillverkades i Macros 3D-skrivare. Bildrenderingar och en monteringsfilm gjordes med hjälp av KeyShot 4, Catia V5 och Photoshop CS6. Även färdiga ritningar som kan användas vid en eventuell tillverkning är bifogade i rapporten.

  • 15.
    Anderberg, Cecilia
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Cabanettes, Frederic
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Dimkovski, Zlate
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Rosén, Bengt-Göran
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Liner Surface Improvements for Low Friction Piston Ring Packs2009In: Society of Tribologists and Lubrication Engineers annual meeting & exhibition 2009: Lake Buena Vista, Florida, USA, 17 - 21 May 2009, Red Hook, NY: Curran Associates, Inc., 2009, p. 455-459Conference paper (Refereed)
  • 16.
    Anderberg, Cecilia
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK). Getinge Sterilization AG, Getinge, Sweden.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Rosén, Bengt - Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK).
    Liner surface improvements for low friction piston ring packs2014In: Surface Topography : Metrology and Properties, ISSN 2051-672X, Vol. 2, no 1, article id 014009Article in journal (Refereed)
    Abstract [en]

    The development of engine components in the automotive industry is governed by several constraints such as environmental legislation and customer expectations. About a half of the frictional losses in an internal combustion engine come from the interactions between the piston assembly and cylinder liner surface. The tribological considerations in the contact between the piston ring and cylinder liner have attracted much attention over the past few decades. Many non-conventional cylinder liner finishes have been, and are being, developed with the aim to reduce friction losses and oil consumption, but the effects of the surface finish on piston ring pack performance is not well understood. One way of reducing friction in the cylinder system is to reduce the tangential load from the piston ring pack, focusing on the oil control ring. However, the side-effect of this is a disappointingly increased oil consumption. In this study a number of different cylinder liner surface specifications were developed and implemented in test engines with the aim of maintaining the level for oil consumption when decreasing the tangential load for the piston ring pack. To improve our understanding of the result, the same surfaces were evaluated in elastic and elasto-plastic rough contact and hydrodynamic flow simulation models. It is shown that oil consumption is strongly related to surface texture on the cylinder liners and at lower speeds (900–1200 rpm), a 'rougher surface' with a high core (e.g. Sk) and valley roughness (e.g. Svk) results in higher oil consumption. At the medium speed range (1200–3600 rpm), oil consumption continues to dominate for the 'rough' surfaces but with a visible influence of a lower oil consumption for a decreased roughness within the 'rough' surface group. 'Smooth' surfaces with a 'smooth' core (Sk), irrespective of the valley component (Svk), show similar oil consumption. For engine speeds above 3600 rpms, an increase in plateau roughness results in higher oil consumption. Throughout the study, standard roughness parameters were computed to compare with the results from engine testing and simulation. Future work will be directed to continuous optimization between oil consumption and friction. Improving the understanding of the functional cylinder system surfaces' ability to form oil films in the cylinder system opens up opportunities, not only in reducing the tangential load of piston ring packs but also in optimizing oil viscosity in order to reduce friction.

  • 17.
    Anderberg, Cecilia
    et al.
    Volvo Cars Corporation, Gothenburg, Sweden.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Rosén, Bengt Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Thomas, Tom R.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Low friction and emission cylinder liner surfaces and the influence of surface topography and scale2019In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 133, p. 224-229Article in journal (Refereed)
    Abstract [en]

    A low friction piston ring pack, with tangential load halved, was tested in engines with four different cylinder liner finishes. Oil consumption, oil temperature and liner surface temperature were monitored at different load and speed levels, under similar test conditions. The two smoother surfaces generally kept lower oil consumption compared to the two rougher ones. Results were correlated using an area-fractal analysis. The relative area of the surface was calculated at different scales and the result was compared with the level of oil consumption for the different liner surfaces at different engine speeds. It was found that oil consumption was strongly correlated with scale for areas of above 1000 μm2 and below 20 μm2.

  • 18.
    Andersdotter, Katarina
    Halmstad University, School of Business, Engineering and Science.
    Tempo50: En temporär mästerskapsbassäng2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
  • 19.
    Andersson, Andreas
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK).
    Larsson, Linus
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK).
    Förbättrad manövrering av lastvagn2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been made on behalf of, and in cooperation with Getinge Sterilization. The purpose of this project has been to develop a solution that makes trolleys of the SMART-trolley series more maneuverable when users are now experiencing them as difficult to maneuver. The handle and the trolleys wheel configuration were identified as the main factors influencing the trolleys maneuverability. Efforts were therefore set up to develop a new handle and a new wheel configuration that solves the maneuvering problem. Along with Getinge a specification of requirements and requests for the new solution was made.

    Initially principle solutions as simple sketches, on possible solutions solving the problem were developed. This was made without taking into account of anyrequirements or requests. Principle solutions are then evaluated against the requirements where the solutions who do not meet the requirements were screened away.

    Handle solutions that made it from the evaluation were presented to Getinge, who selected one of the solutions to develop a prototype from. Therefore, no further evaluations of the handle solutions were made. The selected handle solution underwent primary design process and further develops to best meet requirementsand to be manufacturable in a bending machine. A prototype of the final solution was manufactured.

    Principle solutions for wheel configurations underwent further evaluation, this time against the requests. Wheel configuration solutions that made it from the last evaluation, test prototypes were made and a user test was carried out to obtain a final solution. The result of this thesis is a trolley with an extra wheel pair and a new smaller handle to satisfy the projects purpose.

  • 20.
    Andersson, Antonia
    Halmstad University, School of Health and Welfare.
    Generationsskite: En studie om hur en offentlig verksamhet arbetar inför ett generationsskifte2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 21.
    Andersson, Erik
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Bengtsson, Per-Johan
    Halmstad University, School of Business and Engineering (SET).
    Dark Ages Lunar Interferometer (DALI): Deployment-Rover - Mobility System2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is issued in collaboration with the Jet Propulsion Laboratory (JPL) in Pasadena, California. JPL's primary function is the construction and operation of robotic planetary spacecraft. At the time being JPL has 22 spacecraft and 10 instruments conducting active missions.

    The "Dark Ages" represent the last frontier in cosmology, the era between the genesis of the cosmic microwave background (CMB) and the formation of the first stars. During the Dark Ages, when the Universe was unlit by any star, the only detectable signal is likely to be that from neutral hydrogen (HI).

    The HI absorption occurs in dark matter-dominated overdensities, locations that will later become the birthplaces of the first stars. Tracing this evolution will provide crucial insights into the properties of dark matter and potentially reveal aspects of cosmic inflation. This could be accomplished using a radio telescope located on the far side of the Moon, the only site in the solar system shielded from human-generated interference and, at night, from solar radio emissions.

    Our objective has been the development of the concept of an autonomous rover that would be capable of deploying a large number of low frequency radio antennas on the lunar surface. This is an enabling task for the eventual creation of a radio telescope.

    The project at Halmstad University was divided into three sub-projects, where our area of responsibility has been the development of a concept of the rover's mobility system.

    The result of the project is the concept of a "Rocker-Bogie" suspension system, created in a 3D-environment. A concept which underwent a series of digital analyses and simulations to ensure the compliance with required specifications.

  • 22.
    Andersson, Ida
    et al.
    Halmstad University, School of Health and Welfare.
    Johansson, Emma
    Halmstad University, School of Health and Welfare.
    Man måste gilla det, annars blir det tufft- en studie om mellanchefers psykosociala arbetsmiljö2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna studie var att undersöka mellanchefers upplevelser av den psykosociala arbetsmiljön. Studien baserades på fem utvalda respondenter, där kriteriet var att de befann sig på en mellanposition, med rapporteringsskyldighet både uppåt och nedåt inom organisationen. Insamlingen av data utgick från semistrukturerade intervjuer, och analyserades genom innehållsanalys. Resultatet tyder på att upplevelsen av tydligheten på kraven som ställs, det stora beslutsutrymme och det höga stödet från samtliga parter i organisationen gör att mellancheferna i denna studie upplever den psykosociala arbetsmiljön i organisationen som god. Trots stressigare perioder upplever de att ovan nämnda faktorer reducerar risken för skadlig stress. Till skillnad från tidigare forskning visade analysen av resultatet i vår studie att rollen som mellanchef inte behöver leda till skadlig stress. Slutligen diskuteras studiens arbetsvetenskapliga bidrag och förslag till framtida forskning. 

    Nyckelord: kontroll, krav, mellanchef, psykosocial arbetsmiljö, stöd. 

  • 23.
    Andersson, Magnus
    Halmstad University, School of Business and Engineering (SET).
    KONSTRUKTION AV AUTOMATISERAD SKYDDSANORDNING FÖR ABB / JOKAB SAFTEYS STAKETSYSTEM2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is basically a design project aimed to find a safe and reliable automatic safety device, which is designed to be suitable for highly automated industrial situations. This device fits with ABB / Jokab Safety’s fence systems. These are built up around machines to create safety distances. The automatic protection device assist the operator in situations when loading or going in and out of the danger zone. Therefore, safety is a big matter in these types of devices control circuits. In this design project the solution is being prepared for the future purpose that is to be CE-marked. The work has had a wide topic range with not just elements within the design subject, but also areas such as risk analysis, reliability, and pneumatics. This has resulted in many stimulating destinations in the design process before it finally led into a prototype that has been function tested. The pneumatic control system was then installed to the mechanical design witch led to the final product. During testing some disturbance in the function occurred and this will have to be corrected before some good results can be shown. Testing the prototype generated a lot of information about the product that could be used to optimize its performance.

  • 24.
    Andersson, Marcus
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Tillämpad konstruktion (Digitala verktyg).
    Jönsson, Simon
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Tillämpad konstruktion (Digitala verktyg).
    Konstruktion av kolfiberarmerad motorcykelram2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 25.
    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.

  • 26.
    Andersson, Mikael
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Lingvide, Leo
    Halmstad University, School of Business and Engineering (SET).
    Possibilities for small scale hydropower in Honduras2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With an increased demand of electricity it is in everyone´s interest that investments are made to promote sustainable options, and the question on how to supply clean and sustainable energy is global. In this bachelor’s thesis, funded by SIDA and Åforsk, the intention was to investigate the possibilities for renewable energy in Honduras, a developing country with an expanding energy sector.

    Honduras is Central America´s second largest country, located in-between Guatemala, Nicaragua and El Salvador. The country is one of poorest in the region, and the trade is characterized by the import of oil and export of coffee and fruit.

    Hydropower has played a major role in the development of the Honduran electricity sector, but today oil based thermal power has the largest share of the energy market. It accounts for more than half of the total generation which makes Honduras very vulnerable to changes in the oil price. The remaining share of generation comes from renewable sources, mostly hydropower. The potential for hydropower in Honduras is estimated to be about five times bigger than the current installed capacity. With a constantly rising oil price, building new hydropower or refurbishing old is becoming more and more competitive. This is the reason for this thesis; to investigate the possibilities for small scale hydropower in Honduras. Information has been gathered through contacts with energy organizations as well as examples and experiences from refurbished or upgraded hydropower plants and other relevant hydropower projects. With this information barriers and possibilities in the process of refurbishing, upgrading and building hydropower plants in Honduras have been identified.

    Our conclusion is that developing small scale hydropower in Honduras is very demanding; applying for required permissions, studies, financing, construction etc. are barriers which all require hard work. Considering this we still believe that the possibilities and positive impacts are greater than the barriers and negative impacts when developing small scale hydropower in Honduras thanks to legislated incentives. The positive impacts that can come from building and refurbishing hydropower plants include: cheaper electricity, improved roads, power lines, and schools, promotion of rural electrification and creation of new job opportunities. Small scale hydropower can help Honduras use its natural resources and create a sustainable development for a brighter future.

  • 27.
    Andersson, Robin
    Halmstad University, School of Business and Engineering (SET).
    Electric power quality in low voltage grid: Office buildings and rural substation2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The modern society uses more and more electronic devices needed to being able to function together. This put higher demands on the electrical grid together with that the typical load have changed from the past. Therefore utility companies are obliged to keep the voltage within certain limits for this to function. What exact these limits have been have not always been clear since they have not been gathered in one single document. 

    This thesis is a cooperation with Kraftringen who also has been the initiator. Kraftringen would like to become more proactive in their work regarding electric power quality. For becoming more proactive continuously measurements have to be done but the locations have to be carefully selected in the beginning to get a wider perspective of the grid.

    Energy markets inspectorate (EI) is supervisory of the electric power quality in Sweden and since 2011 they have published a code of statutes (EIFS 2011:2 later 2013:1) intended to summarize limits on voltage. Some of the electrical power quality aspects are not mentioned in EIFS 2013:1 and standards have to be used to find limited values. Flicker and interharmonics are not mentioned in EIFS 2013:1 and for values on flicker the standard SS-EN 50160 has to be used and for interharmonics the standard SS-EN 61000-2-2 state limit values. Besides all this there are standards with stricter limits than EIFS 2013:1 e.g. for total harmonic distortion on voltage were SS-EN 61000-2-2 suggest 6 % instead of 8 %.

    Three different field studies have been conducted in order to get some perception of the present situation regarding electric power quality. Two measurements were conducted on a typical office building because they represents a large part of the typical load in Lund. The third measurement was conducted on a substation in a rural area to get a perception of the situation outside urban areas. 

    These measurements shown that the overall electric power quality was within given limits according to EIFS 2013:1 and different standards. However, conducted measurements shown some interesting results. Both the typical office buildings have a slightly capacitive power factor which results in that the voltage inside the building is going to be slightly higher than at the substation. Since the voltage level at the measured urban substation was above nominal voltage level with about 2-5 % this could be problematic. Another eventual problem with a load with a capacitive power factor is resonance with the inductive parts of the grid like transformers leading to magnified harmonic levels.

    It is suggested that Kraftringen expand their number of permanent electric power quality measurement locations to get a better overview of the present situation. The best suited locations to start with are such that have received complaints earlier, preferably measured on the low voltage side of the transformer for also register the amount of zero sequence harmonics. Next step in the measurement expansion would be substations known to be under higher load than others or substations with a PEN-conductor in a smaller area than the phase conductors, supplying a typical office load with high amounts of third harmonics and unbalance. From this it would be appropriate to spread out the measurement locations geographically to better get to know the grids behaviour. 

  • 28.
    Andersson, Robin
    Halmstad University, School of Business and Engineering (SET).
    Risk och sårbarhetsanalys av fjärrvärmenätet i Lund2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fjärrvärmenätet i Lunds stad började byggas 1963 och består idag av 238 km parvisa fjärrvärmerör. Den teoretiska livslängden för fjärrvärmerör är uppskattad till mellan 50-100 år varför det nu börjar bli dags att reinvestera vissa delar. En tydlig indikering om var på fjärrvärmenätet man ska lägga ekonomiska medel för reinvestering eller underhåll är skadestatistik från olika ledningstyper och fabrikat. Kartläggning av fjärrvärmenätets kompensatorer har genomförts och en riskmatris är framtagen baserad på deras geografiska placering och dimension.

    Resultatet är tänkt att finnas som stöd inför kommande budget på Kraftringen om vilka ledningssträckor som är i störst behov av en reinvestering.

    Grunden i rapporten är hämtad från en forskningsrapport från 1999 med avseende på redan framtagna riskmatriser för ledningstyp och jordart. Riskmatrisen för ledningstyp är modifierad något utefter Lunds lokala skadestatistik för en bättre tillämpning. Skadestatistiken för Lund jämförs med den nationella skadestatistik som Svensk Fjärrvärme samlade in under 1995-2003. Ledningstyper och fabrikat jämförs där den helgjutna betonglådeledningen i Lund uppvisar en betydligt högre skadefrekvens än nationellt. En annan rörledningstyp som sticker med en högre skadefrekvens är direktskummade fasta plastmantelrör av märket Pan-Isovit vilket troligtvis beror på den tidiga utbyggnaden i Lund. Fjärrvärmenätet i Lund var först i Sverige med direktskummade fasta plastmantelrör redan år 1966 av märket Pan-Isovit vilket kan ha föranlett skador på grund av bristande erfarenhet och barnsjukdomar.

    Varje ledningssträcka i den lokala databasen har tilldelats en risk som baseras på riskmatriserna för ledningstyp, jordart samt skadestatistik för berörd typ och konsekvensen av ett avbrott beroende på ledningsdimension. Det ger en indikering på risken för avbrott samt konsekvensen av ett avbrott för olika ledningssträckor, dock utan hänsyn till en eventuell ringmatning.  

    För att en reinvestering ska vara motiverad ska utbytet vara lönsamt. Parametrar som påverkar lönsamheten är värmeförluster, skadefrekvens samt goodwill relativt kunderna. Dessa parametrar är beräknade för samtliga ledningssträckor med befintlig ledning och för reinvestering. Vid värdet ett på goodwill, d.v.s. enbart utebliven försäljning uppnås ingen lönsamhet i en reinvestering för någon ledningssträcka. Det är först vid en goodwill-faktor 8 som lönsamhet uppnås. Ett vanligt värde för goodwill hamnar mellan en faktor 50-100 vilket då gör det lönsamt idag att reinvestera 5,7–8,5 % av fjärrvärmenätet.

  • 29.
    Andersson, Robin
    et al.
    Halmstad University, School of Business, Engineering and Science. 1995.
    Edsinger, Anders
    Halmstad University, School of Business, Engineering and Science.
    Fasadsystem i plåt: Ett system för fasadpaneler som enkelt och snabbt skall kunna monteras.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten är resultatet av examensarbetet som utförts av Robin Andersson ochAnders Edsinger tillsammans med Weland AB våren 2017, som vill utöka sittvarumärke genom att förbättra sitt system för fasadpaneler. Welandsmaskinpark är en av de största i norden och deras plåtbearbetning i form avgallerdurk, trappor, räcken och gångbryggor är mycket stor.Fasadbeklädnad kan bestå utav trä, glas, sten, plåt och mycket mer, och är ettsätt för att förfina byggnadens utseende. Produkten skall kunna tillverkas i enhelautomatiserad stans- och panelbockningsmaskin som företaget nyssinvesterat i. Företagets vilja att förbättra deras system gavs i form av ett projekttill författarna som genom undersökningar av produktionsmöjligheterna kommitfram till en eventuell lösning på problemet.Inledningsvis undersöktes möjligheterna kring tillverkningen, och eninformationssökning i form av förfrågan och litteratursökning utfördes. Allt dettaför att en djupare förståelse om verktyg och tillverkning.Arbetet utformade en metod som sedan följdes och efter många beslut fanns detett vinnande koncept som utvecklades till en prototyp.Resultatet blev ett strukturerat system som enkelt kan monteras upp påbyggnadsväggen. U-profiler skruvas först på väggen och därefter kan paneler lättklickas på utan att särskilda verktyg behövs - ett smart och effektivt sätt somförbättrar arbetsmiljön kring byggplatsen.

  • 30.
    Andersson, Viktor
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Olsén, Martin
    Halmstad University, School of Business and Engineering (SET).
    Kilhus i plast: Omläggning av stålprodukt till produkt i plast2010Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Our bachelor degree thesis was carried out in collaboration with Ivar Petterssons Järnmanufaktur AB in Smålandsstenar. We were asked to replace their wedge housing, used to fasten the wires to the power lines, with a similar structure in a plastic material. The idea for this project started with Ivar Petterssons Järnmanufaktur AB having problems with the casting quality that forced them to perform expensive tests on each of the wedge houses to ensure the quality. They are currently produced in China which is also a major drawback because it requires expensive long delivery times.

    The method we used is Fredy Olsson's Princip- and Primärkonstuktion (1995). We have consistently been in the project on so-called "broad front", which means that you create several sketches, ideas and changes in parallel, and then evaluates all. With this method we were able to largely concentrate on the current part of the project, rather than using the more time-consuming "trail and error" method, which is basically doing one idea at a time, and evaluate them one by one.

    At first we were very optimistic and thought we would be able to order form for the injection moulding process, but as the project progressed we found we were not certain that the product would hold and we were forced to present the solution as a concept that will require testing before it’s finished, and not a finished solution.The results we presented for Ivar Pettersssons Järnmanufaktur is a complete drawing on our primary solution, including the release angles. This is because when they decide to go forth with the project, it will be possible to produce a tool without having to make changes to the drawings. Temporary financial calculation shows that the savings may be realized around 1 300 000 SEK by switching to a plastic construction. However we have not been able to verify hours and therefore no cost estimates for the testing done in Sweden, so the actual amount of money saved is larger.

  • 31. Andreasson, Joacim
    et al.
    Kühn, Daniel
    SpeedCutBox 2.02014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 32.
    Andreasson, Josefin
    et al.
    Halmstad University, School of Health and Welfare.
    Stolt, Lisa
    Halmstad University, School of Health and Welfare.
    "Man vill ju inte vara den som säger det": En kvalitativ undersökning om varför arbetsrelaterade förslitningsskador uppstår trots förebyggande arbetsmiljöarbete2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 33. Andréen, Andreas
    et al.
    Johansson, Robert
    SwiftSense Wardrobe2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 34.
    Aramrattana, Maytheewat
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Extended Driving Simulator for Evaluation of Cooperative Intelligent Transport Systems2016In: SIGSIM-PADS '16: Proceedings of the 2016 annual ACM Conference on SIGSIM Principles of Advanced Discrete Simulation, New York: ACM Digital Library, 2016, p. 255-278Conference paper (Refereed)
    Abstract [en]

    Vehicles in cooperative intelligent transport systems (C-ITS) often need to interact with each other in order to achieve their goals, safe and efficient transport services. Since human drivers are still expected to be involved in C-ITS, driving simulators are appropriate tools for evaluation of the C-ITS functions. However, driving simulators often simplify the interactions or influences from the ego vehicle on the traffic. Moreover, they normally do not support vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication, which is the main enabler for C-ITS. Therefore, to increase the C-ITS evaluation capability, a solution on how to extend a driving simulator with traffic and network simulators to handle cooperative systems is presented as a result of this paper. Evaluation of the result using two use cases is presented. And, the observed limitations and challenges of the solution are reported and discussed. © 2016 ACM, Inc.

  • 35.
    Aramrattana, Maytheewat
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Patel, Raj Haresh
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Englund, Cristofer
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). RISE Viktoria, Gothenburg, Sweden.
    Härri, Jérôme
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Bonnet, Christian
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Evaluating Model Mismatch Impacting CACC Controllers in Mixed2018In: 2018 IEEE Intelligent Vehicles Symposium (IV), IEEE, 2018, p. 1867-1872Conference paper (Refereed)
    Abstract [en]

    At early market penetration, automated vehicles will share the road with legacy vehicles. For a safe transportation system, automated vehicle controllers therefore need to estimate the behavior of the legacy vehicles. However, mismatches between the estimated and real human behaviors can lead to inefficient control inputs, and even collisions in the worst case. In this paper, we propose a framework for evaluating the impact of model mismatch by interfacing a controller under test with a driving simulator. As a proof- of-concept, an algorithm based on Model Predictive Control (MPC) is evaluated in a braking scenario. We show how model mismatch between estimated and real human behavior can lead to a decrease in avoided collisions by almost 46%, and an increase in discomfort by almost 91%. Model mismatch is therefore non-negligible and the proposed framework is a unique method to evaluate them. © 2018 IEEE.

  • 36.
    Arvidson, Carolin
    Halmstad University, School of Business and Engineering (SET).
    Produktutveckling av tilluftsdon2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 37.
    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 %.

  • 38. Arvidsson, Karl-Henrik
    et al.
    Kristensen, Sophie
    Reducering av effekttoppar i Halmstads fjärrvärmesystem: Modellering av ett teoretiskt laststyrningsschema2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On behalf of Halmstads Energi och Miljö (HEM) this paper investigates the possibilities to reduce power peaks in their district heating production through demand side management. The purpose with this paper is to reduce the power peaks with 10 MW and investigate which customers or areas HEM should focus on. In addition, two bottlenecks in the district heating network are analyzed by the effects of demand side management. A theoretical model of demand side management was constructed. The model uses hourly data from production and endeavor to daily average values. The model also included parameters such as storage capacity and manipulated outdoor temperature. The results from demand side management relates to the total daily variations of the district heating system. The demand side management has been applied to a selection of 214 substations and three independent demand side management schemes for the year of 2016, one for each bottleneck and one for the total 214 substations. The choice of substations for demand side management is based on which buildings are connected to them. Criteria for the selection are buildings with high thermal mass, which give high thermal inertia and buildings with high heat demand (large apartment buildings). It is of great interest to investigate how demand side management affects the indoor temperature in selected buildings because limit values cannot be exceeded. The result shows that the power peaks can be reduced by 11.7 MW (mean value) for the whole year excluding the months of spring and summer and for the winter months 13.1 MW (mean value). The reasons why the power peaks can be reduced to a greater extent during the winter months was due to a larger heat demand and heat load variations. Two bottleneck areas applied one theoretic demand side management scheme each where power peaks can be reduced by 0.63 MW(mean value) and 0.7 MW(mean value) excluding spring and summer months and 0.71 and 0.72 only including winter months. The profit from reducing the power peaks for HEM is shorter operating time for the peak heating boilers. The power peaks is later compensated and balanced with renewable bio energy. The simulation from 2016 brings a cost saving to 2.7 million SEK. The profit comprises the cost difference between fossil fuels, natural gas and renewable fuels such as wooden chips. The carbon dioxide reduction during the same period of time was 1671 metric tonne CO2- equivalents.

  • 39.
    Ashokan, Ashwin
    et al.
    Halmstad University.
    Isac, Siriyak
    Halmstad University.
    STUDYING AND DESIGNING OF FRONT MUDGUARDS2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The mudguard in an automobile is used to prevent sand, mud, rocks, liquid and other materials being throne into air by the rotation motion of the tire. In electric vehicles such as Ecoist vehicles will try to reduce the weight of the body part and increase the aerodynamic efficiency by good designs. The purpose of this project is to design a mudguard for this vehicle with more aerodynamic efficiency in a light weight material. In this thesis work a mudguard has been designed in a light weight material and also designed a supporting bracket for the easy installation of the mudguard as well as the tyre to the vehicle.

  • 40.
    Avdullahi, Endrit
    Halmstad University, School of Business, Engineering and Science.
    Effektivisering och utveckling av monteringsutförande i produktion: Från fast till sekventiell montering2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out within the field of production systems and production development and is performed on SP Maskiner i Ljungby AB (SP Maskiner). SP Maskiner has predicted a growing market trend that they want to compete in. This is to be achieved by developing the current assembly process - fixed position assembly, as it fails to cope with the increased demand.

    The underlying method used to obtain the results is derived from Bellgran & Säfsten (2005) framework and is adapted to fit this project.

    The project begins with a present-situation analysis aimed to give a broader insight and a better sense for the system in development. Activities done were: evaluation questions, Rapid Plant Assessment, flow analyses and CAD drawing of current layout. A standard methodology on how to assemble the product was made, with individual process times of each activity, and divided into three workstations. The possible outcome and benefits of this approach was checked using simulation.

    The simulation demonstrates that the three-station divided methodology can increase productivity by about 66 % (an increase of 100 units annually compared to todays rating, 150 [units/year]). The result gives the company extended competitive possibilities and force to stay as a leading competitor in the expected market growth. Furthermore, the result shows the possibilities of simulation in production development projects to analyze possible outcomes of different changes. 

  • 41.
    Averfalk, Helge
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS). Lund University, Lund, Sweden.
    Enhanced District Heating Technology: Maintaining Future System Feasibility2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    When heat demand and high temperature heat supply gradually decreases in the future, then it will effect district heating systems ability to compete on the heat market. A good way to mitigate less district heating feasibility is to operate systems with lower temperature levels and the most conceivable way to achieve lower temperature levels is to decrease return temperatures.

    Thus, this thesis emphasise temperature errors embedded in district heating systems. Only a selection of temperature errors are analysed in this thesis. First, the temperature error that occurs due to recirculation in distribution networks at low heat demands. Second, the temperature error that occurs due to hot water circulation in multi-family buildings. Third, the temperature error that occurs due to less than possible heat transfer in heat exchangers, i.e. too short thermal lengths.

    In order to address these temperature errors three technology changes have been proposed (i) three-pipe distribution network to separate the recirculation return flow from the delivery return flow, (ii) apartment substations to eliminate hot water circulation utilisation, and (iii) improved heat exchangers for lower return temperatures at a constant scenario. Analysis of proposed changes has resulted in annual average return temperatures between 17-21 °C.

    Furthermore, rapid introduction of intermittent renewable electricity supply in the energy system has prompted an increased necessity of power system balancing capacities. Large-scale conversion of power-to-heat in electric boilers and heat pumps is a feasible alternative to achieve such balancing capacities. Analysis of the unique Swedish experience with utilisation of large heat pumps installations connected to district heating systems show that since the 1980s 1527 MW of heat power has been installed, about 80 % of the capacity was still in use by 2013. Thus, a cumulative value of over three decades of operation and maintenance exists within Swedish district heating systems.

    The two papers presented in this thesis are related to future district heating systems through the five abilities of fourth generation district heating (4GDH), which are documented in the definition paper of 4GDH.

  • 42.
    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.

  • 43.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Dalman, Bengt-Göran
    BG Dalman AB, Göteborg, Sverige.
    Kilersjö, Christer
    EKSTA, Kungsbacka, Sverige.
    Lygnerud, Kristina
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS). IVL Svenska Miljöinstitutet, Stockholm, Sverige.
    Welling, Sebastian
    IVL Svenska Miljöinstitutet, Stockholm, Sverige.
    Analys av 4e generationens fjärrvärmeteknik jämfört med 3e generationens: Simulering av sekundärnät i nybyggnationsområde2017Report (Other academic)
    Abstract [sv]

    Bakgrunden till studien är att nya förutsättningar genom energieffektivisering, konkurrens från värmepumpar och nya krav på kundsidan gör en modernisering av fjärrvärmeverksamhet nödvändig. En del av denna modernisering är att kunna dra nytta av de fördelar som lägre temperaturer i näten medför. Därtill skapas genom den nya tekniken förutsättningar för att ta hand om värmekällor som idag inte utnyttjas (t.ex. värme från kylprocesser och annan infrastruktur såsom värme från avloppsvatten och värme från kollektivtrafik).

    Befintlig teknik är beprövad och bygger på att det finns ekonomiska incitament att förbränna biobränsle och avfall. Steget till att pröva en ny teknik där andra värmekällor och en ny gränsdragning gentemot kund blir nödvändig är därför stort och förenat med ett antal frågor. Det är just de frågor som uppkommer i ett fjärrvärmeföretag inför implementering av 4e generationens fjärrvärmeteknik som projektet försöker identifiera. Det blir dock så att enbart en del av frågorna besvaras genom att studien har ett avgränsat fokus. Fokus är på jämförelse mellan ett 3GDHtvårörsystem och ett 4GDH-trerörsystem i ett sekundärnät i ett nybyggnationsområde.

    I projektet simuleras hur utfallet blir för olika parametrar om man hade valt att implementera 4e generationens teknik istället för 3e generationens teknik.

    Resultaten påvisar att:

    • 4e generationens lösning ökar energieffektiviteten i byggnader, detta främst genom att behovet av varmvattencirkulation försvinner.• Beaktas enbart distributionsförluster i näten så är 4e generationen mer effektiv än 3e generationen.• Genom lägenhetsväxlaren i 4e generationens lösning så elimineras risken för Legionella helt. En möjlig barriär för 4e generationens teknik består dock i att boverkets byggregler inte är konstruerade för att varmvattencirkulation inte finns.• Lägenhetsväxlarna innebär en kostnad per lägenhet vilket begränsar lösningens kostnadseffektivitet jämfört med en större värmeväxlare i fastighetens bottenplan. Idag är 4e generationens teknik lämpad för fastigheter med 10-15 lägenheter, är det fler lägenheter blir 4e generationens lösning dyrare än den konventionella 3e generationens lösning.• En viktig aspekt med 4e generationens lösning att värmeförlusten från huset förflyttas från fastighetsägaren till fjärrvärmeföretaget, genom att värmeleverans sker till varje lägenhet och inte vid husvägg. Initialt kan sådan börda på fjärrvärmeföretaget verka negativ med avseende på kostnad. Diskussionerna i projektet mynnade ut i att parterna enas om att affären blir mer rättvisande och att fastighetsägaren får ökad insyn i värmeförbrukningen vilket, med rätt affärsmodell, kan skapa ökat förtroende och en möjlighet att dela på förlusten mellan de två parterna.

    Projektet har omfattat löpande dialog med EKSTAs VD vilket varit värdefullt för att skapa förståelse kring fastighetsägarens perspektiv och frågor rörande 4e generationens teknik. Därtill har en workshop med EKSTAs driftspersonal hållits för att diskutera relevansen i de resultat som tagits fram. I projektet ingår BengtGöran Dalman med över 35 års erfarenhet av fjärrvärmeverksamhet vid Göteborg Energi. Projektets verklighetskoppling leder till slutsatsen att det inte föreligger någon särskild driftsproblematik för implementering av 4e generationens system.

    Som en egen del i projektet uppmärksammas den diskussion som förs i branschen kring möjligheten att dra nytta av billig el, främst under perioder då det blåser mycket och det blir ett överskott av el i elnätet. I studien analyseras möjligheten att inte använda en konventionell pelletspanna som tilläggsvärmekälla utan en eldriven panna. Resultaten visar att med dagens styrning genom skatter och avgifter så är det inte möjligt att dra nytta av att det förekommer perioder med mycket lågt elpris. Rådande regelverk stödjer istället installationer såsom pelletspannor.

    © ENERGIFORSK

  • 44.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Ottermo, Fredric
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Pipe Sizing for Novel Heat Distribution Technology2019In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 7, article id 1276Article in journal (Refereed)
    Abstract [en]

    This paper assesses pipe sizing aspects for previously proposed, novel, low heat distribution technology with three pipes. Assessment issues include heat loss, pressure loss, and pipe sizing for different typical pipe configurations. This assessment has been provided by the analysis of a case area with single-family houses. Concerning heat loss, the proposed three-pipe solutions have the same magnitude of heat loss as conventional twin pipes, since lower return temperatures compensate for the larger heat loss area from the third pipe. Regarding pressure loss, the main restriction on the size of the third pipe is limited to the pressure loss in the third pipe. Thermostatic valves to manage the flow rate of the third pipe are advocated, since alternative small pumps have not been found to be commercially available. The pipe sizing recommendation is that the third pipe for recirculation purposes can be two to three standard pipe sizes smaller than the corresponding supply and return pipe, if no prosumer is connected in the heat distribution network.

  • 45.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Efficient heat distribution in solar district heating systems2018In: SDH Solar District Heating: Proceeding, 2018, p. 63-66Conference paper (Refereed)
    Abstract [en]

    This paper contains a short analysis showing the main benefit for solar district heating when a novel heat distribution concept with low temperatures is applied. The analysis is performed by comparing the annual solar heat output from a solar collector field for current heat distribution temperatures in Sweden with the corresponding output for the novel heat distribution concept. The results show that the new low temperature concept provides 66% more solar heat for a typical solar collector. Hereby, the solar collector field can be reduced with 40%, giving a corresponding cost reduction for solar heat generated. Another result is that the cost gradient for lower costs from lower return temperatures is five times higher for solar district heating compared to current heat supply in Swedish district heating systems. One major conclusion is that high heat distribution temperatures in current European district heating systems are a major barrier for the competitiveness of solar district heating.

  • 46.
    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.

  • 47.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Essential improvements in future district heating systems2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 116, p. 217-225Article in journal (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. © 2017 The Authors. Published by Elsevier

  • 48.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Framtida fjärrvärmeteknik: Möjligheter med en fjärde teknikgeneration2017Report (Refereed)
  • 49.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Novel low temperature heat distribution technology2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 145, p. 526-539Article in journal (Refereed)
    Abstract [en]

    Lower future heat demands and lower availability of non-fossil high temperature heat supply are expected future market conditions that restrain the long-term viability of contemporary district heating systems. Hence, current district heating technology should be enhanced to increase system performance in new heat distribution areas. This paper aims to outline a proposal for technical improvements required to achieve lower annual average return temperatures in new residential buildings to improve viability in future market conditions. The proposed technical solution consists of three principle changes: three-pipe distribution networks, apartment substations, and longer thermal lengths for heat exchangers. The three technical modifications aims at addressing system embedded temperature errors. Furthermore, a simulation model was developed to assess the proposed technical solution concerning different energy performances of buildings and different thermal lengths in heat exchangers. The results show that implementation of the three technical modifications reaches time-weighted annual average return temperatures of 17–21 °C with supply temperatures of about 50 °C. The results also verify the increased necessity to separate the network return flows into delivery and recirculation flows in residential substations as energy performance in buildings increase.

  • 50.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Felsmann, Clemens
    Technische Universität Dresden, Dresden, Germany.
    Rühling, Karin
    Technische Universität Dresden, Dresden, Germany.
    Wiltshire, Robin
    Building Research Establishment (BRE), Garston, Watford, United Kingdom.
    Svendsen, Svend
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Li, Hongwei
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Faessler, Jérôme
    University of Geneva, Geneva, Switzerland.
    Floriane, Mermoud
    University of Geneva, Geneva, Switzerland.
    Quiquerez, Loïc
    University of Geneva, Geneva, Switzerland.
    Transformation Roadmap from High to Low Temperature District Heating Systems: Annex XI final report2017Report (Other academic)
1234567 1 - 50 of 690
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