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  • 1.
    Abdeljaber, O.
    et al.
    Qatar University, Doha, Qatar.
    Younis, Adel
    Qatar University, Doha, Qatar.
    Alhajyaseen, W.
    Qatar University, Doha, Qatar.
    Analysis of the Trajectories of Left-turning Vehicles at Signalized Intersections2020In: Transportation Research Procedia, 2020, Vol. 48, p. 1288-1295Conference paper (Refereed)
    Abstract [en]

    Internationally, an annual number of more than a million fatalities are caused by road traffic crashes, with particularly signalized intersections being crash prone locations within the highway system. An accumulation of conflicts between drivers is caused by the different movements (through and turning) from different directions at the intersection; hence, studying the trajectories of turning vehicles is an important step towards improving traffic safety performance of these facilities. In view of that, the current paper aims at providing further insight into the behaviour of left-turning vehicles (right-hand traffic rule) at signalized intersections in the State of Qatar. At first, a total of 44 trajectories of free-flowing vehicles were manually extracted from a recorded video for a single approach of Lekhwair signalized intersection in Doha City, State of Qatar. After that, the extracted trajectories were statistically analysed in an attempt to explore the factors affecting the path of left-turning vehicles at signalized intersections. The results suggest that the characteristics of the extracted paths are significantly related to the vehicle’s entry speed, minimum speed throughout its turning manoeuvre, and the lateral distance between the exit point and the curb (i.e., targeted exit lane). Provided that the speed parameters can be fairly an indication to the driving behaviour, it can be concluded that the driver’s attitude plays an important role in drawing the manoeuvre of a turning vehicle as does the pre-selection of the exit lane. Finally, the effort presented in this paper can be regarded as a way forward towards understanding the behaviour of turning vehicles at signalised intersection in the State of Qatar.

  • 2.
    Abdeljaber, O.
    et al.
    Linnaeus University, Växjö, Sweden.
    Younis, Adel
    Qatar University, Doha, Qatar.
    Alhajyaseen, W.
    Qatar University, Doha, Qatar.
    Extraction of Vehicle Turning Trajectories at Signalized Intersections Using Convolutional Neural Networks2020In: The Arabian Journal for Science and Engineering, ISSN 1319-8025, Vol. 45, no 10, p. 8011-8025Article in journal (Refereed)
    Abstract [en]

    This paper aims at developing a convolutional neural network (CNN)-based tool that can automatically detect the left-turning vehicles (right-hand traffic rule) at signalized intersections and extract their trajectories from a recorded video. The proposed tool uses a region-based CNN trained over a limited number of video frames to detect moving vehicles. Kalman filters are then used to track the detected vehicles and extract their trajectories. The proposed tool achieved an acceptable accuracy level when verified against the manually extracted trajectories, with an average error of 16.5 cm. Furthermore, the trajectories extracted using the proposed vehicle tracking method were used to demonstrate the applicability of the minimum-jerk principle to reproduce variations in the vehicles’ paths. The effort presented in this paper can be regarded as a way forward toward maximizing the potential use of deep learning in traffic safety applications.

  • 3.
    Abdul Gabar, Allan
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Protic, Dennis
    Halmstad University, School of Business, Engineering and Science.
    Kartläggning av arbetsledarens arbetsfördelning i byggproduktion: En undersökning av möjliga förbättringar inom yrkesrollen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every company strives for maximum efficiency. The construction industry, which is complex while margins are small, makes efficiency an important issue. In the construction industry today,the high demand for production is to be delivering high quality projects as well as within certain timeframes. In order for this to be achieved, there is a great demand for work management in production. Therefore, we have chosen to analyze improvement areas within the supervisor’s role.The purpose of this report is to investigate the supervisor’s situation in the construction industry.Furthermore, the purpose is to identify work-related tasks in the professional role that have the potential for efficiency enhancement.A frequency study has been conducted in three different workplaces where we have followed three different supervisors for a total of nine days to get an insight into how the supervisors spend theirtime. Interviews have been conducted with supervisors for an even broader view of the study. Literature search has been made where we have found theories that we also present. During the course of the study we have found that there are a few improvement areas. As an enhancement, we think digitalization should be implemented, and everyone should keep order and clean up afterwards, more feedback to employees, and develop communication.

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  • 4.
    Abdulhalim, Mohammed
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Angmyr, Sebastian
    Tillämpning av Partnering vid ombyggnad av bostäder: Vad krävs för ett framgångsrikt partnering projekt?2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 5.
    Abrahamsson, Mickael
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Berg, Simon
    Halmstad University, School of Business, Engineering and Science.
    Tillfälliga modulhus - en ekonomisk och kvalitetsmässig analys2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The populations of Sweden are right now facing an acute housing shortage. One of the reasons of this is the huge amount of immigrants that have been taken in over recent years. The construction industry hasn’t been able to keep up with the rising demand and is right now looking for a solution. Modular housing is one solution that has been proposed by Boverket, the national board of housing, building and planning as it reduces construction times. The purpose of this paper is to analyze this method and the potential consequences/gains it has. In this paper we have used three different case studies were we have done 3 interviews in each.   This research concludes that the problem doesn’t lie within the quality or the costs associated with modular housing. It lies within the temporary building permits that are often used when time is of the essence. 

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  • 6.
    Abrahamsson, Victoria
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Eckerberg, Christopher
    Halmstad University, School of Business, Engineering and Science.
    Insourcad polsk arbetskraft i svensk byggindustri: En studie utifrån NCCs arbetslednings perspektiv2018Independent thesis Basic level (university diploma), 12 HE creditsStudent thesis
    Abstract [en]

    The need for labor in the construction sector is today greater than the supply. As a result, several companies use foreign labor, which constitutes challenges. Previous studies highlight that problems can arise mainly in the categories of cultural differences, communication, security, quality and time.

    The purpose of this study is to investigate issues of foreign labor from the perspective of managers. Furthermore, the study aims to highlight positive effects with insourcing, a difference to previous research where the workforce has been external.

    The study is conducted through qualitative methodology where review of existing literature has highlighted apparent issues to handle. In addition, semistructured interviews where conducted with the case company management team to investigate experienced issues as well as the impact of the insourcing strategy. The analysis and discussion of the interviews results in a list of improvement suggestions for companies using foreign labor. A general conclusion is that insourcing is beneficial to construction companies using foreign labor, as it provides continuity and improved opportunity for development and guidance. Furthermore, the education and development of the workers is easier to follow up.

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  • 7.
    Abrams, Philip
    Halmstad University, School of Business, Engineering and Science.
    Simulering och känslighetsanalys av ett pumpkraft-dagvattendammsystem: En utvärdering av potential för småskalig energilagring av solelsöverskott eller arbitrage2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The global move to more sustainable and renewable energy sources causes increased fluctuations in theelectric market. That fact combined with the Swedish regulations on micro producers make high levels ofself-use critical and have increased the interest in energy storage of energy from intermittent sources.Cooperation with Eksta AB have provided the opportunity to evaluate an innovative energy storage conceptfor a future exploitation area of around 17,2 hectares planned residential and urban area. This bachelorthesis studies the potential of using stormwater management ponds for small-scale energy storage in theform of pumped hydro energy storage (PHES). The focus is on storage of surplus energy from a solarenergy system designed for micro production and local energy supply. However, it also evaluates thepotential of using the equivalent dimensions for energy storage which storage level only change whenbuying or selling electricity at market prices for arbitrage purposes.Potential in the form of financial benefit and increased self-use of solar energy are studied through aquantitative methodology that, in the case of storing surplus energy from a solar system, use a simulationmodel developed for this thesis that takes Eksta´s contractual electric specifications into account. Toevaluate the case of energy storage for arbitrage a simulation model is used in the form of an algorithmbaseddrive strategy named “Optimal”, which has been recreated from research in the field of energy storageand drive strategies. The level of innovation is high on account of including such as energy additions to thestorage from rain water management, energy losses from dispersion of stored stormwater to surroundingground layers, it´s novel focus on a stormwater pond for energy storage, the rarely studied combination ofPHES and small scale solar systems and finally that the dimensions of the pump and turbine that is neededin PHES is based on PaT (pump as turbine) technology, allowing the reverse drive of a centrifugal pumpto operate as a turbine.Sensitivity analysis is included to increase the understanding of PHES-stormwater systems in the case of Eksta and as a concept for energy storage. The work also includes a brief examination of relevant regulationsin order to supply a wider perspective.The result shows that the implementation of a PHES-stormwater system during the years 2018 and 2019increased the self-use of generated solar energy by 28,59 % and provide the joint financial benefit of 5989SEK. The simulation model of energy storage for arbitrage during the years 2018 and 2019 resulted in thecombined financial benefit of 699 SEK when “Optimal” operation strategy is used and 678 SEK with apractically applicable operation strategy.The main conclusion is that PHES-stormwater systems as an energy storage for small-scale solar surplushas high potential to increase the self-use of solar energy but relatively low potential to increase the financialbenefits of small-scale solar systems. From the sensitivity analysis it can be concluded that the simulatedPHES-stormwater system is sensitive to small and medium ranged changes in storage capacity, efficiency,rate of dispersion, set electrical buying price and selectivity of which hours to empty the storage. This whilebeing generally insensitive to small and medium ranged variations in installed peak effect of the solar system,filling/emptying time and the relative size of the turbine compared to the pump.The conclusion from the simulation of arbitrage application is that the potential for financial benefit inthese circumstances is extremely low. The sensitivity analysis lead to the conclusion that the system issensitive to small and medium ranged variations in storage capacity, efficiency, filling/emptying time andmarginal operation costs.Besides the limited financial benefit, other potential hindrances may be the legality of connecting the systemelectrically, lack of financial benefits given to larger but still small-scale solar systems and the eventuality ofdisrupting the main function of the stormwater pond, which is purifying stormwater.

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  • 8.
    Adiego Abad, Sonia
    Halmstad University, School of Business and Engineering (SET).
    Degree project:HOSTEL2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A construction project including planning, cost estimation and design of a Hostel on a property in the city of Halmstad.

  • 9.
    Afkari, Arash
    Halmstad University, School of Business and Engineering (SET).
    Sustainable Low-Cost Housing in Ethiopia: A Study of CSSB-Technology2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project is about sustainable low-cost housing in Ethiopia with a focus on CSSB-technology, which is one method of constructing houses. The project allowed me to visit Ethiopia during seven weeks in 2010, to observe, gather information and to perform tests regarding the specific subject. It is a sub-project to a larger research project initiated in 2002 at Halmstad University in an attempt to introduce low-cost housing technologies for the Kambaata Region in Ethiopia. The aim of the research project has been to develop and test new, sustainable, low-cost building technologies intended for the population, with regard to local traditions, needs and affordability.

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  • 10.
    Ahankoob, Alireza
    et al.
    School of Property, Construction and Project Management, RMIT University, Melbourne, Australia.
    Manley, Karen
    Halmstad University, School of Business, Innovation and Sustainability.
    Abbasnejad, Behzad
    School of Property, Construction and Project Management, RMIT University, Melbourne, Australia.
    The role of contractors’ building information modelling (BIM) experience in realising the potential values of BIM2022In: International Journal of Construction Management, ISSN 1562-3599, Vol. 22, no 4, p. 588-599Article in journal (Refereed)
    Abstract [en]

    There has been recently a growing attention towards the potential benefits of building information modelling (BIM) in construction business processes from both academia and industry practitioners. While prior research has emphasised that there is a link between the proficiency of construction companies to use BIM and the realisation of BIM benefits, little evidence exists to capture this relationship. The aim of this study is to explore the extent to which prior BIM experiences influence the perception of industry experts on potential BIM benefits. The influence of years of BIM experience on the discernment of BIM potential benefits was examined through a survey of Australian building contractors. The results of the analysis of variance (ANOVA) showed that BIM experience was a significant factor in the realisation of potential BIM benefits. The results suggest that an increase in years of BIM experience foster a better understanding of BIM benefits, which consequently can lead to a more inspiring movement towards the adoption of BIM by construction organisations. The main contribution of this article is to increase awareness towards the adoption and implementation of BIM by making a link between BIM proficiency and an increased perception of BIM potential benefits in construction organisations. © 2019 Informa UK Limited, trading as Taylor & Francis Group.

  • 11.
    Ahankoob, Alireza
    et al.
    RMIT University, Melbourne, Australia.
    Manley, Karen
    Halmstad University, School of Business, Innovation and Sustainability.
    Hon, Carol
    Queensland University of Technology, Brisbane, Australia.
    Drogemuller, Robin
    Queensland University of Technology, Brisbane, Australia.
    The influence of building information modelling on the absorptive capacity of project-based organisations2023In: Architectural Engineering and Design Management, ISSN 1745-2007, E-ISSN 1752-7589, Vol. 19, no 1, p. 1-21Article in journal (Refereed)
    Abstract [en]

    Absorptive capacity (AC) is a theoretical construct that measures the capacity of an organisation to absorb knowledge from external sources to sustain competitive advantage. Information dispersion makes it difficult for project-based organisations (PBOs) to absorb new ideas. The current study uses AC theory to examine how the use of building information modelling (BIM) affects the capacity of building contractors to absorb new information and become more competitive. A desktop study of secondary sources was undertaken to assess if there is a potential link between BIM and contractor AC. This revealed that the potential benefits of BIM’s technical features are motivated through its functional attributes. Exploratory factor analysis (EFA) was used to clarify the underlying relationship of a cluster of variables. The results of EFA led to the confirmed three categories for BIM functional attributes, including: (1) integration, (2) comprehensibility, and (3) transparency. Multiple regression analysis was used to explore the latent relationship between BIM functional attributes and contractor AC. The regression analysis of survey data, which was gathered from 56 building contractors in Queensland, Australia, showed that the transparency function of BIM functional attributes significantly correlated with acquisition and transformation dimensions of contractor AC. The study confirms a link between BIM and contractor AC, providing further evidence of the importance of BIM in sustaining the competitive advantage of project-based organisations. © 2021 Informa UK Limited, trading as Taylor & Francis Group.

  • 12.
    Ahlberg, Jimmie
    et al.
    Halmstad University, School of Business, Innovation and Sustainability.
    Herbertsson, Gustav
    Halmstad University, School of Business, Innovation and Sustainability.
    Skjuvkraftskapacitet för infästning i närheten av fri kant på prefabricerade betongelement2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Correct dimensioning of mounting plates near an edge in concrete is of utmost importance to prevent breakage. This study, which is primarily experimental, investigates the capacity of a certain type of embedded mounting plate when placed adjacent to an underlying edge. The purpose is to gain an understanding of how these mounting plates should be dimensioned against edge breakage and to investigate how a transverse bar affects the shear capacity near an edge. The study presents the results from practical tests and compares them with calculations made according to the Eurocode. The results show that the actual fastening has a higher strength than what is described in the calculation models from the standards. Full-scale testing and dimensioning guidelines based on testing led to comparable results in the experiment. The method used in the experiment yielded promising results and shows that calculations according to the Eurocode do not correspond to reality. Instead, the capacity turns out to be significantly higher than what is shown after calculations according to interpretations of standards.

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  • 13.
    Al Haboub, Nour
    et al.
    Halmstad University.
    Ali, Abd Algani
    Halmstad University.
    Mikroproportionering av kompletterande cementbaserade material2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study will deal with a new type of concrete that focuses on cement particles. As you alreadyknow today, concrete is one of the most used materials in the world, and the negative is that it has acontributing factor to pollution with as much as 5% of global carbon dioxide pollution.To reduce this, a new environmentally friendly concrete was produced that reduces pollution anddamage to the environment.The type of concrete we have studied has a higher compressive strength than the reference mix.Many tests were carried out to produce concrete that is environmentally friendly with highcompressive strength.The study will highlight the actual effect of the cement particles when large particles that perform afilling effect are not as important compared to the small particles that enter the hydration process andreplace with large particles of limestone (>0.036 mm). Through the method (Normal Limestone in anew abode), concrete has gained greater compressive strength than the reference mix.With the results achieved in this study, the construction sector is given the opportunity to useconcrete with higher strength and be more environmentally friendly in the future.

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  • 14.
    Al Nasseri, Hammad Abdullah
    et al.
    Lund University, Lund, Sweden & Sultan Qaboos University, Al Khoudh, Sultanate of Oman.
    Widén, Kristian
    Lund University, Lund, Sweden.
    Aulin, Radhlinah
    Lund University, Lund, Sweden.
    A taxonomy of planning and scheduling methods to support their more efficient use in construction project management2016In: Journal of Engineering, Design and Technology, ISSN 1726-0531, E-ISSN 1758-8901, Vol. 14, no 3, p. 580-601Article in journal (Refereed)
    Abstract [en]

    Purpose: The implementation and control processes of project planning and scheduling involve a wide range of methods and tools. Despite the development and modification and integration of the project management theory with newer scheduling approaches in particular, practitioners’ views on the efficiency and effectiveness of these methods and tools differ. This situation can be attributed in part to a lack of understanding of the most appropriate basis for implementing these methods and tools. This study, therefore, aims to overcome this deficiency by conceptualizing and adopting a taxonomy of planning and scheduling methods.

    Design/methodology/approach: The study is based on a review and discourse analysis of the literature covering a large number of theoretical and empirical studies. The underlying theories of various planning and scheduling methods were analyzed with respect to the taxonomy criteria adopted in the study.

    Findings: Using the taxonomy, the key characteristics of planning and scheduling methods considered in this study were identified and interpreted. These included concepts and theories; key features; suitability and usability; and benefits and limitations. Overall, the findings suggest that project managers should consider taxonomy as a support tool for selecting and prioritizing the most appropriate method or combination of methods for managing their projects. Recommendations include the need for more advanced or multi-dimensional taxonomies to cope with the diversity of project type and size.

    Originality/value: The results of the study allow project managers to improve their current practices by utilizing taxonomy when considering the implementation of planning and scheduling methods. Moreover, taxonomy can be considered as a tool to promote learning on the part of those less experienced in planning and scheduling. Taxonomy can be considered as an initial platform for further research in this area. © 2016, © Emerald Group Publishing Limited.

  • 15.
    Alali, mohammad
    et al.
    Halmstad University.
    Ali, Mohammad
    Halmstad University.
    Prognostisering av form rivnings tider med hjälp av PPB: En studie om hur PPB effektiviserar gjutplaneringen i kallt väder2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    In Sweden, castings occur all year round, similar to all other countries in the world.However, since Sweden have fairly low temperatures in most months of the year, winter casting becomes a hot topic to talk about. Winter casting is largely followed by many measures to prevent early freezing in mature concrete. A critical success factor during the construction phase is to take off the formwork at the adequate strength and at the right time. The concrete must reach adequate strength without additives otherwise the formwork is left standing longer than required, which has a major impact on the schedule and budget. Therefore, companies and contractors strive to complete this task in an orderly manner to minimize construction time and design costs. The study’s great emphasis is to scrutinize and compare the forecasted simulations byprogram PPB against measured values of temperature development and strength growth that was measured in the concrete from the casting time up to a few days later. The comparison will test how effective PPB is to forecast the heat evolution in concrete after casting, especially during the winter.The methods used to achieve the result are:A temperature register from the thermocouples that measures the heat evolution in concrete.Forecasting of construction elements that have the same properties and conditions as in reality.Literature studies that describe the methodology for this necessity. Results of the work indicate promising success for the program after multipleconformities between measurement values and simulations. Additionalrecommendations and documentations were provided for better results.

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  • 16.
    Albertsson, Anton
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Skoglund, Lukas
    Halmstad University, School of Business, Engineering and Science.
    Rullarmering: Att adoptera en armeringsmetod2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rebar carpet is an innovation that favors the working environment of the rebar workers and saves time. Reinforcement workers today are a vulnerable group. Heavy lifts and backbreaking postures are a part of their everyday work. It is already established that work with rebar carpets is both time-saving, economically beneficial and from a working environment point of view better than traditional reinforcement work. Despite all benefits it is used in rather few projects today.

    The purpose of this study is to identify how the construction industry embraces new innovations related to in situ concrete with post-tensioned reinforcement. The goals are to find out how designers, contractors and manufacturers are working to adopt rebar carpets in the construction process and to shed light on, factors affecting the adoption.

    The study is based on semi-structured interviews with designers, contractors and a representative of a rebar manufacturing company.

    Designers and contractors have not, generally speaking, been actively working to adopt rebar carpet. The governing factors for the use of rebar carpets is the designers and contractors knowledge and previous experience of rebar carpet. The contractors who have previous experience of rebar carpet can imagine using rebar carpet again and contractors with no previous experience believe that they need more knowledge of rebar carpet before they dare to try. Design engineers who have designed for rebar carpet before has it in mind when they design other projects. Designers who have no previous experience of rebar carpet demand more knowledge about how they can facilitate the use of rebar carpet.

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  • 17.
    Alfara, Osama
    et al.
    Halmstad University.
    Alfara, Ahmad
    Halmstad University.
    Re-Con Zero ballast som ersättning för jungfruligt bergmaterial i betongproduktion: En studie av dess egenskaper och effekter2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study explores the use of Re-Con Zero aggregates (RCZ-aggregates), a material made from recycled concrete and a two-component powder product, as an alternative to traditional virgin aggregates material in concrete production. The primary purpose of the study is to contribute to a more sustainable and circular concrete industry, where surplus or excess  concrete does not become a waste problem but a valuable resource. The study aims to fill a knowledge gap regarding how RCZ-aggregates impacts the fresh and hardened properties of concrete.

    The study investigates whether RCZ-​​aggregates can match the performance of traditional aggregates materials with respect to key concrete properties such as density, water absorption, and other mechanical properties like slump, air content, and compressive strength.

    Experimental methods included tests to compare between concrete mixes with traditional aggregates and those containing RCZ-aggregates. These tests measured the density and water absorption of RCZ-aggregates, as well as slump and air content at different times (0, 30, and 60 minutes) and compressive strength at various curing times (1, 7, and 28 days) for all mixes.

    The results from these tests showed that concrete made with RCZ-aggregates generally had higher water absorption and lower density compared to traditional mixes. Despite these material-induced differences, the concrete with RCZ-aggregates achieved compressive strength values that were similarly within the range of a normally distributed material at all tested times. This demonstrates that RCZ-aggregates is considered suitable in terms of compressive strength.

    The conclusions from the study underscore that RCZ-aggregates , made from residual concrete, is a fully functioning alternative to virgin aggregates material in concrete, with good compressive strength. However, there are clear differences in slump, where the behavior of the concrete varies depending on whether it is mixed with newly produced or saturated RCZ-aggregates. The study also reveals that both newly produced and saturated RCZ-aggregates affect the air content of concrete differently compared to concrete made with virgin aggregates material.

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  • 18.
    Algeröd, Oskar
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Davidsson, Tobias
    Halmstad University, School of Business, Engineering and Science.
    Hållfasthet i helväggselement av cementbunden träull2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cement bonded wood-wool as external walls have been used around the world since the 1980s. They can have different appearances, wood-wool slabs connected to each other into larger wall elements that are raised between concrete columns and beams. Another type is hollow wood-wool blocks that are stacked on each other and filled with concrete to make an external wall. In 2004 a new building system was launched in Sweden, large prefabricated wall elements of wood-wool. They are connected to each other with concrete columns and beams integrated in the elements to make an external wall. This report is looking into if the concrete beams and columns for the building system are needed. In the report three different tests were made to get the mechanical properties of the prefabricated wood-wool elements. Results showed that there was a large different in the density between the wall elements and it also showed that the modulus of rupture varied between 0.248-0.449 MPa on three identical wall elements. The characteristic modulus of rupture was three times higher than documented in previous reports of a similar wall. The conclusion of this report is that the concrete beams and columns should still be in the wall system.

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  • 19.
    Alhali, Sara
    Halmstad University, School of Business, Innovation and Sustainability.
    Formminneslegeringar: En jämförandestudie mellan en ny typ av förstärkning och traditionella förstärkning av broar2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den industriella revolutionen kom med behovet av att bygga byggnader och broar, till en början förstod man inte vikten av armering och förstärkning av konstruktion. Men med tiden behövde man komma på någon strategi att göra konstruktionen starkare och mer hållbar, och det var då man började använda sig av förstärkning.

    I dagens moderna samhälle är det vanligare att bygga med betong, betong är det viktigaste byggmaterialet i världen. Det har flera egenskaper som garanterar en lång livslängd för konstruktionen; dess hållbarhet och styvhet är av störst intresse för att designa betongkonstruktioner. Andra egenskaper såsom täthet och bearbetbarhet är också viktiga. För att utnyttja betongegenskaperna korrekt måste nästan alla strukturer förstärkas på ett eller annat sätt. Därför har man under en lång period gjort stora forskningar på hur man kan göra betong starkt i draghållfasthet och inte bara i tryck.

    Moderna komplicerade konstruktionsformer kräver nya förstärkningsmetoder, komplexiteten i den nya strukturen både när det gäller höjd och bredd har nödvändiggjort behovet av nya metoder för betongarmering. En metod är användningen av järn-baserade minneslegeringar (Fe-SMA), genom forskning har det visat sig vara en effektiv metod för armering av stål. SMAs har unika egenskaper och det mest speciella är att det återgår till sin ursprungliga form även när det har deformerats. Som ett resultat av detta möjliggör det förstärkning av betong av vilken form och storlek som helst, de goda limegenskaperna hos betong och järn gör installationen komplett.

    Detta examensarbete resulterade att SMA har väldigt unika egenskaper som kommer att göra stora skillnader i byggbranschen. Detta gäller främst hos broar och är en väldigt aktuell metod som har förmågan att anpassa sig till den omgivande miljön. Utöver det kan den även justera sig själv för att säkerställa optimal och säker drift under normala och svåra belastnings villkor och det minimala kravet för underhåll.

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  • 20.
    Alhoushan, Ahmad
    et al.
    Halmstad University, School of Business, Innovation and Sustainability.
    Almasri, Ahmad
    Halmstad University, School of Business, Innovation and Sustainability.
    Energieffektivisering Av asfalttillverkning: Ett Hållbart tillvägagångs sätt Genom värmelagring Och Varmdosering: Effektiva åtgärder för energibesparingar och 𝐶𝑂2-minskning.2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry strives for climate neutrality by 2045-2050 with a focus oncollaboration, innovation, and efficient use of resources to reduce greenhouse gasemissions and promote sustainable construction methods. This degree project from theBuilding Engineering program at Halmstad University investigates energy efficiency andoptimization of the asphalt manufacturing process, especially heat storage in silos, incollaboration with Skanska Industrial Solutions.The study applies qualitative methods, including interviews with experts and visits to anasphalt plant in Sperlingsholm, Halmstad. The theoretical framework includes sustainabledevelopment, sustainable road networks, hot mix asphalt (HMA), and design andmaterials for heat storage silos.The research methodology included data collection, interviews, field visits andsimulations with COMSOL Multiphysics to analyse temperature changes and comparedifferent silo design options. Autodesk AutoCAD was used to create 2D drawings.The results emphasize energy efficiency and sustainability in asphalt manufacturing, withthe potential to reduce greenhouse gas emissions through optimized silo design andinsulation. Specifically, the implementation of heat storage silos shows a significantreduction in oil consumption and 𝐶𝑂2 emissions. The study further recommends researchfor validation and improvement in real production environments and contributes withinsights into sustainable construction methods, underscoring the need for technologicalinnovation to meet the environmental challenges in the construction industry.

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  • 21.
    Ali, Hani
    et al.
    Halmstad University, School of Information Technology.
    Sunnergren, Pontus
    Halmstad University, School of Information Technology.
    Scenanalys - Övervakning och modellering2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Autonomous vehicles can decrease traffic congestion and reduce the amount of traffic related accidents. As there will be millions of autonomous vehicles in the future, a better understanding of the environment will be required. This project aims to create an external automated traffic system that can detect and track 3D objects within a complex traffic situation to later send these objects’ behavior for a larger-scale project that manages to 3D model the traffic situation. The project utilizes Tensorflow framework and YOLOv3 algorithm. The project also utilizes a camera to record traffic situations and a Linux operated computer. Using methods commonly used to create an automated traffic management system was evaluated. The final results show that the system is relatively unstable and can sometimes fail to recognize certain objects. If more images are used for the training process, a more robust and much more reliable system could be developed using a similar methodology. 

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  • 22.
    Alinaitwe, Henry Mwanaki
    et al.
    Makerere University, Kampala, Uganda.
    Widén, Kristian
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB). Lund University, Lund, Sweden.
    Mwakali, Jackson
    Makerere University, Kampala, Uganda.
    Hansson, Bengt
    Lund University, Lund, Sweden.
    Innovation Barriers and Enablers that Affect Productivity in Uganda Building Industry2007In: Journal of Construction in Developing Countries, ISSN 1823-6499, E-ISSN 2180-4222, Vol. 12, no 1, p. 59-75Article in journal (Refereed)
    Abstract [en]

    The construction industry has of recent been blamed for lack of innovation. Lack of innovation in the industry is believed to be responsible for the decreasing or stagnant levels of productivity in comparison with other industries. This paper reviews the major barriers and enables to innovation in general. Propositions were made about the factors that affect innovation in the construction industry which were then formulated into a questionnaire. A survey was made on building contractors in Uganda, a developing country, targeting those with financial strength, large in size, and with high capacity to carry out big projects. The identified factors were then ranked and correlated. The level of training in science, engineering and technical education, and the level of research and development at the industry level are looked at as the greatest innovation enablers in building that will drive forward labour productivity. The size of the domestic market and the level of security are the worst innovation barriers that lead to low productivity in the building industry in Uganda. Contractors, policy makers and the government should address the identified factors in order to improve productivity.

  • 23.
    Alinaitwe, Henry
    et al.
    Makerere University, Kampala, Uganda.
    Widén, Kristian
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB). Lund University, Lund, Sweden.
    Mwakali, Jackson
    Makerere University, Kampala, Uganda.
    Hansson, Bengt
    Lund University, Lund, Sweden.
    Building firm innovation enablers and barriers affecting productivity in Mwakali and Taban-Wani2006In: Advances in Engineering and Technology: Proceedings of the First International Conference on Advances in Engineering and Technology 16-19 July 2006, Entebbe, Uganda / [ed] Jackson A. Mwakali & Gyavira Taban-Wani, Oxford: Elsevier, 2006, p. 268-276Conference paper (Refereed)
  • 24.
    Allerbo, Emma
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Waldemarsson, Hanna
    Halmstad University, School of Business and Engineering (SET).
    Adobe - Technology of Everybody: Low Cost Housing in Ethiopia2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The traditional building techniques in Ethiopia today contain a lot of wood. Because ofdeforestation the forest cover in the country has been decreased. A part of a solution would bethe exclusion of wood in construction and then the adobe technology is a good alternative. Adobe technology involves blocks made from local soil that mixed with water and straw asreinforcement. The sundried blocks can be bricked up to walls. As mortar the same wetmixture can be used.

    This report contains analyzed soil characteristics in the high altitude located Asella region todetermine its suitability for adobe blocks. The design of a kindergarten in Alem Maya is alsocarried out.

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    Adobe - Technology of Everybody: Low Cost Housing in Ethiopia
  • 25.
    AlNasseri, Hammad Abdullah
    et al.
    Lund University, Lund, Sweden.
    Widén, Kristian
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB). Lund University, Lund, Sweden.
    Aulin, Radhlinah
    Lund University, Lund, Sweden.
    Towards a Taxonomy of Planning and Scheduling Methods in the Context of Construction Management2013In: Proceedings from 7th Nordic Conference On Construction Economics And Organisation 2013: Green Urbanisation – Implications For Value Creation / [ed] Ole Jonny Klakegg, Kari Hovin Kjølle, Cecilie G. Mehaug, Nils O.E. Olsson, Asmamaw T. Shiferaw & Ruth Woods, Trondheim: Akademika forlag, 2013, p. 570-581Conference paper (Refereed)
    Abstract [en]

    Planning and scheduling are considered as one of the most difficult but most important processes from perspectives of project management. These processes involve implementation of a widerange of planning methods used by different organizations with various levels of planning knowledge. The planning methods for scheduling can be classified as traditional methods (e.g. line of balance, Gantt chart and critical path) and modern methods (e.g. last planner and critical chain). Over time these methods had advanced from paper based to computer based. However, some project planners still prefer using the traditional methods despite other new alternatives. Users of those methods have different perspectives about the efficiency and effectiveness of the different planning methods used to manage different projects. Evidences from the secondary data found from extensive literatures have been used to assess the planning and scheduling methods mentioned above. A taxonomy describing each of the method in terms of their theories, key features, application areas, benefits and limitations is presented. The preliminary outcome of this paper may provide a tool to aid organizations in selecting and prioritizing the most appropriate methods to be developed and implemented in planning and scheduling of their projects. It also initializes a theoretical base for more rapid taxonomy studies on the use of different planning and scheduling approaches. As an overall, the present paper reminds practitioners of common ground about its important insights on how such taxonomy studies have potential to make scope of those methods and tools clearer, especially when they compare among them within the same application contexts.

  • 26.
    Al-Samarai, Omar
    Halmstad University, School of Business, Engineering and Science.
    Svart arbetskraft inom byggbranschen: En studie av små byggföretag2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry has for several decades demonstrated a problem with financial crime black labour, while the state loses tens of billions of SEK each year due to tax cuts. The government has been fighting undeclared work for several years, and the construction industry is also working to support healthy competition and remove the unequal working conditions that this entails. The purpose of the study is to examine black labour in small companies in the construction industry, the problems that workers are exposed to and why they choose to work in this way. The study was limited to examining small construction companies and the collection of empirical material took place in the Stockholm region. The work is based on previous findings regarding undeclared work as well as semi-structured anonymous interviews conducted with employers and employees working in two small construction companies in the Stockholm region. Both companies make use of illegal workforce and all respondents who lined up admit that they either work illegally full time or alongside their regular jobs. The results show that the undeclared work does not contain any directly bad or unequal working conditions per se which has been the result in some previous studies. The problem is rather that there is no protection if events occur at work and that the state is withheld tax for work done. Furthermore, the study shows that it is a direct desire of the private individuals who are customers to have the work done as undeclared work. 

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  • 27.
    Alshihbi, Raneem
    et al.
    Halmstad University, School of Business, Innovation and Sustainability.
    Hameed, Tiba
    Halmstad University, School of Business, Innovation and Sustainability.
    Från nord till syd - Praxis kring tidsplanering i Sverige och Saudiarabien: Projektledning utifrån tidsplanering och uppföljning2024Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This study explores and compares scheduling and follow-up practices in construction projects between the Kingdom of Saudi Arabia (KSA) and Sweden. By applying qualitative methods, including previous literature studies and interviews with experts in the construction industry in both countries, the thesis aims to gain an in-depth understanding of the differences and similarities that characterize the time planning and follow-up processes in these two contexts.

    The results of the study highlight the specific methods used in KSA and Sweden and identify the underlying factors that influence the effectiveness and success of these methods. The study shows that the two countries have sufficient technical capacity for development and efficiency. The most influencing role in the time planning is the difference in the use of competencies and experiences, the work environment and leadership and their impact on the work. By analysing and comparing data from the different sources, this work aims to contribute to insights that can be useful for improving the scheduling and follow-up of construction projects, not only in KSA and Sweden.

    This comparative study is expected not only to increase the understanding of cultural and organizational differences between the two countries but also to provide practical advice and recommendations to promote effective time planning and follow-up in the construction sector. By using a qualitative methodology, this work strives to offer an indepth insight into an important aspect of project management and contribute to the development of knowledge in the field. 

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  • 28.
    AL-Taie, Zaid
    et al.
    Halmstad University, School of Business, Innovation and Sustainability.
    Haddad, Melissa
    Halmstad University, School of Business, Innovation and Sustainability.
    Undersökning av energieffektivitet och renoveringsåtgärder på ett småhus från miljonprogrammet.2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates methods to increase energy efficiency in the renovation of small houses built during the Million Homes Programme (1965-1974), focusing on a house in Stockholm. Increased awareness of the building sector's contribution to greenhouse gas emissions has made the renovation of existing buildings a crucial strategy for reducing environmental impact. The study maps the current energy performance of the house and identifies energy losses in accordance with the Swedish Building Regulations (BBR). Through simulations and calculations, the energy consumption before and after the renovation is compared. The study employs a combination of qualitative research methods, including a case study, to analyze data from measurements, expert consultations, and energy simulations using Energiberäkning.se. The pay-off method and emission factors from SABO are used to evaluate the cost-effectiveness and environmental impact of measures such as window replacement and the installation of energy-efficient systems. The results show that air-to-air heat pumps can reduce energy consumption by up to 55% and CO₂ emissions by up to 383,246 g CO₂/kWh for windows and 1,082,916 g CO₂/kWh for FTX systems. Triple-glazed windows offer a faster payback period of 8.8 years. The study provides insights into how specific renovation measures can meet modern energy requirements and contribute to sustainable development, making renovation more profitable than new construction when considering economic and environmental aspects.

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  • 29.
    Altarabichi, Mohammed Ghaith
    et al.
    Halmstad University, School of Information Technology.
    Fan, Yuantao
    Halmstad University, School of Information Technology.
    Pashami, Sepideh
    Halmstad University, School of Information Technology.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Center for Applied Intelligent Systems Research (CAISR).
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology.
    Predicting state of health and end of life for batteries in hybrid energy buses2020In: Proceedings of the 30th European Safety and Reliability Conference and the 15th Probabilistic Safety Assessment and Management Conference / [ed] Baraldi, Piero; Di Maio, Francesco; Zio, Enrico, Singapore: Research Publishing Services, 2020, p. 1231-1231Conference paper (Refereed)
    Abstract [en]

    There is a major ongoing transition from utilizing fossil fuel to electricity in buses for enabling a more sustainable, environmentally friendly, and connected transportation ecosystem. Batteries are expensive, up to 30% of the total cost for the vehicle (A. Fotouhi 2016), and considered safety-critical components for electric vehicles (EV). As they deteriorate over time, monitoring the health status and performing the maintenance accordingly in a proactive manner is crucial to achieving not only a safe and sustainable transportation system but also a cost-effective operation and thus a greater market satisfaction. As a widely used indicator, the State of Health (SOH) is a measurement that reflects the current capability of the battery in comparison to an ideal condition. Accurate estimation of SOH is important to evaluate the validity of the batteries for the intended application and can be utilized as a proxy to estimate the remaining useful life (RUL) and predict the end-of-life (EOL) of batteries for maintenance planning. The SOH is computed via an on-board computing device, i.e. battery management unit (BMU), which is commonly developed based on controlled experiments and many of them are physical-model based approaches that only depend on the internal parameters of the battery (B. Pattipati 2008; M. H. Lipu 2018). However, the deterioration processes of batteries in hybrid and full-electric buses depend not only on the designing parameters but also on the operating environment and usage patterns of the vehicle. Therefore, utilizing multiple data sources to estimate the health status and EOL of the batteries is of potential internet. In this study, a data-driven prognostic method is developed to estimate SOH and predict EOL for batteries in heterogeneous fleets of hybrid buses, using various types of data sources, e.g. physical configuration of the vehicle, deployment information, on-board sensor readings, and diagnostic fault codes. A set of new features was generated from the existing sensor readings by inducing artificial resets on each battery replacement. A neural network-based regression model achieved accurate estimates of battery SOH status. Another network was used to indicate the EOL of batteries and the result was evaluated using battery replacement based on the current maintenance strategy. © ESREL2020-PSAM15 Organizers. Published by Research Publishing, Singapore.

  • 30.
    Altarabichi, Mohammed Ghaith
    et al.
    Halmstad University, School of Information Technology.
    Sheikholharam Mashhadi, Peyman
    Halmstad University, School of Information Technology.
    Fan, Yuantao
    Halmstad University, School of Information Technology.
    Pashami, Sepideh
    Halmstad University, School of Information Technology.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology.
    Del Moral, Pablo
    Halmstad University, School of Information Technology.
    Rahat, Mahmoud
    Halmstad University, School of Information Technology.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology.
    Stacking Ensembles of Heterogenous Classifiers for Fault Detection in Evolving Environments2020In: Proceedings of the 30th European Safety and Reliability Conference and the 15th Probabilistic Safety Assessment and Management Conference / [ed] Piero Baraldi; Francesco Di Maio; Enrico Zio, Singapore: Research Publishing Services, 2020, p. 1068-1068Conference paper (Refereed)
    Abstract [en]

    Monitoring the condition, detecting faults, and modeling the degradation of industrial equipment are important challenges in Prognostics and Health Management (PHM) field. Our solution to the challenge demonstrated a multi-stage approach for detecting faults in a group of identical industrial equipment, composed of four identical interconnected components, that have been deployed to the evolving environment with changes in operational and environmental conditions. In the first stage, a stacked ensemble of heterogeneous classifiers was applied to predict the state of each component of the equipment individually. In the second stage, a low pass filter was applied to smoothen the predictions cast by stacked ensembles, utilizing temporal information of the prediction sequence. © ESREL2020-PSAM15 Organizers. Published by Research Publishing, Singapore.

  • 31.
    Alzghoul, Ahmad
    et al.
    Halmstad University.
    Hyseni, Burim
    Halmstad University.
    Övergång till högre stålhållfastheter - konsekvensanalys2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 32.
    Andersen, Linn
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Widell, Hanna
    Halmstad University, School of Business, Engineering and Science.
    En villaleverantörs möjlighet till etablering i Finland: analys av för- och nackdelar2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction market has, as a result of the crisis in Europe been uncertain in recent years. During the year 2013, the construction will be stabilized, in particular Finland. The geographical proximity between Sweden and Finland and similarities in cultures and climates makes Finland a coveted market for many Swedish companies.

    Differences in national regulations and guidelines, which are produced by the authorities in different countries, are examples of barriers that may hamper the process, including for Swedish villa suppliers, to establish themselves on the Finnish market. It may be useful when facing a new export drive, to look up what similarities and differences there are between the countries building codes, to prevent mistakes and unnecessary costs to the project work.

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  • 33.
    Andersson, Annie
    et al.
    Halmstad University, School of Business, Innovation and Sustainability.
    Elin, Arvidsson
    Halmstad University, School of Business, Innovation and Sustainability.
    Långsiktiga klimatförändringars påverkan på hållbarheten av befintliga byggnader: En studie avseende grundkonstruktionen platta på mark2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Climate change affects the world in various ways and its consequences also play a significant role in the construction industry. In the year 2100, the climate in Sweden is predicted to produce higher temperatures and more precipitation. To ensure the resilience of buildings against these factors, the potential problems arising from them need to be identified.

    The purpose of this report is therefore to investigate how existing foundations are affected by future climate scenarios with regard to the foundation type slab on ground. It is crucial to highlight the problems that different climate scenarios lead to when it comes to sustainability of existing buildings. 

    This report investigates the relative humidity levels in three different slab-on-ground foundation constructions, demonstrating the variation in moisture content under two established RCP scenarios (RCP 4.5 and RCP 8.5). The analysis is conducted via a case study involving foundation structures built using construction techniques from different time periods, aligning with the buildings present in Kungsbacka today. 

    Calculations have been conducted to investigate the relationship between increased temperature and relative humidity in all three constructions. The result shows that as the temperature rises, the relative humidity increases. During the summer period for the climate scenario RCP 8.5, all constructions have a humidity of over 90 % which defines the relationship between relative humidity and increased temperature. During the winter period for the same climate scenario, the values vary significantly for all three constructions. This is further discussed in the discussion part of the report.

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  • 34. Andersson, Björn
    et al.
    Andersson, Isabell
    Vid val av formställning: Ur ett företagsperspektiv2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 35.
    Andersson, Marcus
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Erro, Ossian
    Halmstad University, School of Business, Engineering and Science.
    BIM-modeller som bygghandling: Spårning av problem med BIM-modeller som bygghandling gentemot traditionella ritningar2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 36. Andersson, Martin
    et al.
    Vikard, Peter
    Säkrare byggarbetsplatser: En rapport om arbetsmiljö i allmänhet och fallolyckor i synnerhet2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden there are 299 000 working in the construction industry. The construction industry is one of the industries where most accidents occur every year. During the last ten years there have been 111 death accidents in the construction industry and 48 of them were falling accidents. That means, in average, one death accident every month.

    Falling accidents gives serious injuries to the persons who are affected by them. It is anticipated that this report will investigate the factors beyond the falling accidents and also to present proposals that can decrease the number of falling accidents in the future.

    To secure a healthy and safe construction site it is of great importance that both the employers and the employees cooperate towards the same goal. A good work environment will benefit both the employer, the project will be finished in time with a good profit margin, and the employees will be satisfied to everyday come to a secure construction site.

    The result of this report indicate that it’s very important to plan the work before executing it ,so that everyone involved knows what they are going to do. This, together with, better management from the company’s directors to the employees will reduce the risk for accidents to occur.

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    Säkrare byggarbetsplatser
  • 37. Andersson, Mimmi
    et al.
    Andersson, Louise
    Ansvarsfrågan vid fuktspärrsarbete i våtutrymme2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This final project is an investigation about the responsibility in rooms where the walls and floors are exposed or partly exposed to irrigation of water, as a bathroom, laundry room and WC.

     

    The cost for all water damage is valued for 5 000 000 000 SEK each year. How is this possible with all information about the problem and good materials? Who is responsible?

     

    Incites had been made in the subject throw reading reports and participation in courses about how to make a room mention above. Discussions have been made with workers in the trade of making the walls waterproof.

    The conclusion in the rapport is about who´s responsible for the damages and will pay the cost of the renovation. The responsibility is discussed between the contractor and the insurance company. If the room is waterproof system is made by the rules the insurance company pays. If it’s not the contractor is paying or if they don’t know how the carpenter is the owner has to pay for the new bathroom.

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    Ansvarsfrågan vid fuktspärrsarbete i våtutrymme
  • 38.
    Andersson, Niclas
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB).
    BIM Adoption in University Teaching Programs: The Swedish Case2013In: Proceedings of CITA BIM Gathering Conference 14-15 November 2013 / [ed] Dr. Allan Hore, Barry McAuley, Dr. Roger West, Dublin: The Construction IT Alliance , 2013, p. 163-168Conference paper (Refereed)
    Abstract [en]

    Implementation of BIM in the construction industry relies on sufficient knowledge and skills about BIM in order to gain momentum and success. Thorough understanding of the possibilities as well as challenges related to the application of BIM constitutes essential drivers for the adoption of BIM among all the industry actors throughout the construction process. Thus, there is a need for supply of knowledge and skills about BIM and its implications on the organisation, communication, management, business models etc. in construction. Accordingly, universities play an important role as a knowledge and skills supplier that helps to provide the necessary conditions for the implementation of BIM in the construction industry. This study investigates how the curricula of engineering and architectural teaching programs at Swedish universities and university colleges have responded to the apparent and increasing demand for BIM competences in industry. The study relies on a survey of 10 universities and 8 university colleges that provide engineering and architectural teaching programs at a master’s and/or a bachelor’s level. The findings show that bachelor’s engineering programs at university colleges generally have adopted BIM into the curricula to a somewhat larger extent compared to engineering programs at a master’s level. The BIM-adoption in architectural programs is, however, significantly limited. Further, the degree of BIM-adoption differs significantly between the respective teaching programs. Only few universities have adopted BIM as an integrated subject in courses that deal with general construction related issues. The predominant approach is to implement BIM-subjects as discrete teaching modules, i.e. stand-alone courses, rather than as a cross disciplinary aspect implemented in a number of the existing courses. Besides, a considerate mismatch is identified between the technical characteristics of the BIM curricula at universities and the process-oriented approach to BIM represented by the industry. Thus, the universities would benefit from a closer collaboration with the industry in BIM-related matters and they need to take on a strategic approach to BIM at an overall university or program level in order to avoid isolated BIM initiatives at a single course level.

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    BIM Adoption in University Teaching Programs
  • 39.
    Andersson, Niclas
    et al.
    Lund University, Lund, Sweden.
    Widén, Kristian
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB). Lund University, Lund, Sweden.
    Construction Innovation Systems - A Sector Approach2005In: Understanding the Construction Business and Companies in the New Millennium / [ed] Kalle Kähkönen & Martin Sexton, Helsinki: VTT – Technical Research Centre of Finland & RIL – Association of Finnish Civil Engineers , 2005, p. 203-213Conference paper (Refereed)
    Abstract [en]

    Recent studies depict the general need to increase and improve innovation in the construction industry. Innovation processes are traditionally described and analysed either on a macro level or a micro level. Production in construction is basically project oriented, as opposed to manufacturing industries for which most of these theories are developed. It is not fully sufficient to study innovation from a micro or a macro level due to the effects of the project orientation and the large number of actors in the construction industry. The objective of this paper is to present a model of the construction innovation systems from a sector systems approach. The study rests upon findings in the area of innovation systems in general and construction innovation systems in particular on one hand and construction sector systems analysis on the other. This paper presents arguments for the development of activity based innovation systems at a construction sector level.

  • 40.
    Andersson, Paul
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Ladan, Igor
    Halmstad University, School of Business and Engineering (SET).
    Transport av volymelement: Förutsättningar ur ett företags perspektiv2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Building with volume element is relatively new and has started to increase more and more. The regulations that exist to regulate and determine how the transports of volume elements are to be conducted are diffuse and not very well adjusted to address the issues with transporting volume elements. Today there are a number of instances that a company has to turn to in order to get a somewhat different view, what regulations say and interpret it in order to know what applies and not applies regarding the transportation of volume elements. regulations. The rules that are in place make it tough for the volume element producing companies to develop and continue to be active on the market. New stricter laws regarding environment safe building leads to the volume elements getting larger which makes it even harder to transport them from a law and rules point of view.

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  • 41.
    Andersson, Peter
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Svensson, Adam
    Halmstad University, School of Business, Engineering and Science.
    Nulägesanalys av byggarbetsledares användning av IT-verktyg: Digitala verktyg inom byggproduktion2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Use of computer based construction plan programs were introduced as early as in the 1970’s and have since then been under constant develop. Their functions and durability have during the last twenty years gone from only being used in the projection and office stage to being a useful tool at the actual construction site too.

    This report is a status analysis regarding what thoughts and perspectives younger and newly added generation of construction foremen have on the use, implementation and development of digital tools in the Swedish construction business, and the potential information exchange at the construction sites.

    The report is a compilation of interviews with respondents representing four different established Swedish construction companies. The results of the interviews are compared with available literature, which are results of previous research and pilot projects that have been done the subject.

    It also contains a view of how the communication transpire when problems occur on construction plans and how this is managed by the construction foreman. The approach is currently depending on the nature and significance of the problem, and also how far the companies have come in the development and the commitment from their employees.

    The results show that digital tools and the possibility of efficient information technology is available, but the use of these are less frequent than the respondents expected in their role as a construction foremen.The implement, use of modern working methods and the obtaining of digital tools are for example depending on economic and function barriers. The construction business is also currently in a generation change which bring a younger generation in to the business which have more experience of using information technology and digital tools, that have created a difference to the earlier generations, both in use an knowledge.

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  • 42.
    Andersson, Sebastian
    et al.
    Halmstad University.
    Burnelius, Jesper
    Halmstad University.
    Miljöbetong2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 43.
    Andersson, Simon
    et al.
    Halmstad University.
    Glittmark, Filip
    Halmstad University.
    Tillämpning av fackverksanalogi på trappupplag2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 44.
    Andreasson, Fredrik
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Mårtensson, Johan
    Halmstad University, School of Business, Engineering and Science.
    Bascement i en samverkanskonstruktion: En fuktteknisk analys med inriktning på uttorkning2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One of today’s biggest concerns in many industries is indubitably the environmental concern we arestanding against. Not least in the construction industry is this a big factor in creating and evolvingconstruction methods. The construction industry alone stands for 19 % of the greenhouse gas emissionsin Sweden.This has led to an increased use of wood in buildings and different construction details. Such as woodenframes in higher buildings and as in this study is very relevant, concrete composite slabs. The use of CLTconcretecomposite slabs utilizes the tensile strength from wood and the compression strength fromconcrete. While concrete has high carbon emissions this has led to development of Bascement which isa composition of Portlandcement and fly ash.This project will analyze the use of Bascement in composite slabs and how the impact of moistureevaporation from the hardening concrete will affect the CLT slab. These results will be compared with analready published study which analyzed the moisture properties and effects on a CLT-concretecomposition with standard Portland cement. By using the same model and parameters and onlychanging the cement the moisture is being measured in a 28-days timeframe with laboratory work forshort term vapor transmissions and an additional simulation for long term moisture content.

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  • 45.
    Angel, Linn
    Halmstad University, School of Business, Innovation and Sustainability.
    Att bygga utifrån krav på konstruktion och hållbarhet: En jämförelse mellan dåtid och nutid2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This case study compares the function and framework of a building from 1898 with the requirements regarding sustainability and strength when building today. The purpose of this study is to get a better understanding of the requirements by investigating a building that was built without them.

    The requirements on a new building’s sustainability are today applied to old buildings that undergo extensive renovation. Two measurements to ensure high sustainability are primary energy and the heat transfer coefficient. A well-insulated building has a low heat transfer coefficient and will require less energy to heat and therefore be more energy efficient and more sustainable.

    Calculations have been made to determine the strength of the roof and the walls according to the Eurocodes and the nationally determined parameters, EKS. The primary energy and heat transfer coefficient has been calculated and compared to the mandatory provisions, Boverkets byggregler, BBR.

    The result shows that the framework is strong enough to take care of the loads it is exposed to. Most of the requirements regarding sustainability fail to be met. Although in conclusion it should be possible to meet some, if not all, the requirements with further renovation without harming the cultural value of the building.

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  • 46.
    Anheim, Fredrik
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Widén, Kristian
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB). Lund University, Lund, Sweden.
    Learning organizations in the Swedish construction area2001In: Construction Economics and Organization: Proceedings of the 2nd Nordic Conference on Construction Economics and Organization: 24–25 April 2001, Gothenburg, Sweden / [ed] Jan Bröchner, Per-Erik Josephson & Bengt Larsson, Göteborg: Dept. of Building Economics and Management, Dept. of Service Management, Chalmers Univ. of Technology , 2001, p. 259-266Conference paper (Refereed)
  • 47.
    Aramrattana, Maytheewat
    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), Göteborg, Sweden.
    A Simulation-Based Safety Analysis of CACC-Enabled Highway Platooning2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cooperative Intelligent Transport Systems (C-ITS) enable actors in the transport systems to interact and collaborate by exchanging information via wireless communication networks. There are several challenges to overcome before they can be implemented and deployed on public roads. Among the most important challenges are testing and evaluation in order to ensure the safety of C-ITS applications.

    This thesis focuses on testing and evaluation of C-ITS applications with regard to their safety using simulation. The main focus is on one C-ITS application, namely platooning, that is enabled by the Cooperative Adaptive Cruise Control (CACC) function. Therefore, this thesis considers two main topics: i) what should be modelled and simulated for testing and evaluation of C-ITS applications? and ii) how should CACC functions be evaluated in order to ensure safety?

    When C-ITS applications are deployed, we can expect traffic situations which consist of vehicles with different capabilities, in terms of automation and connectivity. We propose that involving human drivers in testing and evaluation is important in such mixed traffic situations. Considering important aspects of C-ITS including human drivers, we propose a simulation framework, which combines driving-, network-, and traffic simulators. The simulation framework has been validated by demonstrating several use cases in the scope of platooning. In particular, it is used to demonstrate and analyse the safety of platooning applications in cut-in situations, where a vehicle driven by a human driver cuts in between vehicles in platoon. To assess the situations, time-to-collision (TTC) and its extensions are used as safety indicators in the analyses.

    The simulation framework permits future C-ITS research in other fields such as human factors by involving human drivers in a C-ITS context. Results from the safety analyses show that cut-in situations are not always hazardous, and two factors that are the most highly correlated to the collisions are relative speed and distance between vehicles at the moment of cutting in. Moreover, we suggest that to solely rely on CACC functions is not sufficient to handle cut-in situations. Therefore, guidelines and standards are required to address these situations properly.

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  • 48.
    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), Göteborg, Sweden.
    Englund, Cristofer
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research. RISE Viktoria, Göteborg, 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), Göteborg, Sweden.
    Safety Evaluation of Highway Platooning Under a Cut-In Situation Using SimulationManuscript (preprint) (Other (popular science, discussion, etc.))
    Abstract [en]

    Platooning refers to an application, where a group of connected and automated vehicles follow a lead vehicle autonomously, with short inter-vehicular distances. At merging points on highways such as on-ramp, platoons could encounter manually driven vehicles, which are merging on to the highways. In some situations, the manually driven vehicles could end up between the platooning vehicles. Such situations are expected and known as “cut-in” situations. This paper presents a simulation study of a cut-in situation, where a platoon of five vehicles encounter a manually driven vehicle at a merging point of a highway. The manually driven vehicle is driven by 37 test persons using a driving simulator. For the platooning vehicles, two longitudinal controllers with four gap settings between the platooning vehicles, i.e. 15 meters, 22.5 meters, 30 meters, and 42.5 meters, are evaluated. Results summarizing cut-in behaviours and how the participants perceived the situation are presented. Furthermore, the situation is assessed using safety indicators based on time-to-collision.

  • 49.
    Aramrattana, Maytheewat
    et al.
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Habibovic, Azra
    RISE Research Institutes of Sweden, Gothenburg, Sweden.
    Englund, Cristofer
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). RISE Research Institutes of Sweden, Gothenburg, Sweden.
    Safety and experience of other drivers while interacting with automated vehicle platoons2021In: Transportation Research Interdisciplinary Perspectives, E-ISSN 2590-1982, Vol. 10, article id 100381Article in journal (Refereed)
    Abstract [en]

    It is currently unknown how automated vehicle platoons will be perceived by other road users in their vicinity. This study explores how drivers of manually operated passenger cars interact with automated passenger car platoons while merging onto a highway, and how different inter-vehicular gaps between the platooning vehicles affect their experience and safety. The study was conducted in a driving simulator and involved 16 drivers of manually operated cars. Our results show that the drivers found the interactions mentally demanding, unsafe, and uncomfortable. They commonly expected that the platoon would adapt its behavior to accommodate a smooth merge. They also expressed a need for additional information about the platoon to easier anticipate its behavior and avoid cutting-in. This was, however, affected by the gap size; larger gaps (30 and 42.5 m) yielded better experience, more frequent cut-ins, and less crashes than the shorter gaps (15 and 22.5 m). A conclusion is that a short gap as well as external human–machine interfaces (eHMI) might be used to communicate the platoon's intent to “stay together”, which in turn might prevent drivers from cutting-in. On the contrary, if the goal is to facilitate frequent, safe, and pleasant cut-ins, gaps larger than 22.5 m may be suitable. To thoroughly inform such design trade-offs, we urge for more research on this topic. © 2021 The Author(s)

  • 50.
    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).
    Englund, Cristofer
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research. RISE Viktoria, Gothenburg, Sweden.
    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.
    Simulation of Cut-In by Manually Driven Vehicles in Platooning Scenarios2017In: 2017 IEEE 20th International Conference on Intelligent Transportation Systems (ITSC), Piscataway, NJ: IEEE, 2017, p. 1-6Conference paper (Refereed)
    Abstract [en]

    In the near future, Cooperative Intelligent Transport System (C-ITS) applications are expected to be deployed. To support this, simulation is often used to design and evaluate the applications during the early development phases. Simulations of C-ITS scenarios often assume a fleet of homogeneous vehicles within the transportation system. In contrast, once C-ITS is deployed, the traffic scenarios will consist of a mixture of connected and non-connected vehicles, which, in addition, can be driven manually or automatically. Such mixed cases are rarely analysed, especially those where manually driven vehicles are involved. Therefore, this paper presents a C-ITS simulation framework, which incorporates a manually driven car through a driving simulator interacting with a traffic simulator, and a communication simulator, which together enable modelling and analysis of C-ITS applications and scenarios. Furthermore, example usages in the scenarios, where a manually driven vehicle cut-in to a platoon of Cooperative Adaptive Cruise Control (CACC) equipped vehicles are presented. © 2017 IEEE.

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