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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Ombyggnation av nedlagd affärslokal till familjebostad / Rebuilding of a former grocer´s shop to a family residence

Holsten, Linda, Tolff, Lina January 2004 (has links)
<p>I samhället Hults Bruk ligger en nedlagd brukshandel, från 1951, som idag fungerar som samlingslokal för de boende i området. Holmen Skog, som äger alla fastigheter i området, planerar nu för en ombyggnation av den gamla brukshandeln till familjebostad. </p><p>Vår uppgift var att utforma ett planlösninsförslag anpassat till en tvåbarnsfamilj för den aktuella byggnaden. Utöver detta skulle vi även upprätta rumsbeskrivning och köksuppställning samt ge förslag på ledningsdragningar, tomtutformning och källarplanlösning. </p><p>Holmen hade vissa krav och önskemål för ombyggnationen. Dessa innebar huvudsakligen att eftersträva en rimlig kostdandsnivå och att hålla ner arbetsinsatserna genom att bevara många av de befintliga väggarna. Dessutom var det viktigt att inte göra för stora ingrepp i byggnadens fasad eftersom Holmen vill bevara det ursprungliga utseendet. Vi har även följt krav och anvisningar i BBR, SBN1980 och BÄR. </p><p>Vi har vid framtagandet av denna rapport tillämpat lärdom och litteratur från kurserna Byggnads och samhällsplanering och Installationsteknik. Vi har haft kontinuerlig konsultation med vår handledare på Byggrosen som har hjälpt oss med diverse byggnadstekniska frågor. Samtliga ritningar har upprättats med hjälp av AutoCad. </p><p>Vårt slutgiltiga förslag omfattar en bostad om fem rum och kök. Vi har prioriterat en öppen planlösning för att erhålla stora fri ytor och stora gemensamma ytrymmen. Många nya väggar måste resas då flera rum ska byggas. Dessutom behövs det sättas in nya fönster i de nya rummen. Vi har planerat för nya rördragningar och installationer då dessa är i originalmodell och behöver bytas ut. Nya vattenledningar samt ett nytt ventilationssystem bör installeras. Bostadens tillhörande tomt, som utgör en yta på ca 250 kvm, har vi utformat med bland annat en stenbelagd uteplats och nya planteringsytor. Resultatet av vår bostadsutformning innebär rimliga kostnader och arbetsinsatser samt att vi i stor utsträckning har lyckats bevara byggnadens yttre utseende.</p>
122

Rostskyddssystem för stålprofiler : Tekniska egenskaper, ekonomi och miljöfrågor / Anti-corrosive treatments of steel beams : technical properties, economy and environment

Gustafsson, Lena January 2004 (has links)
<p>Nästan alla stålkonstruktioner måste rostskyddas. Undantaget är de som står inomhus i torr luft. Ett rostskydd kan utföras på flera olika sätt, men de vanligaste är att stålet målas med rostskyddsfärg eller att det varmförzinkas. Innan detta kan utföras måste stålet förbehandlas. Det är viktigt att den utförs noggrant för annars kan kvarvarande föroreningar börja rosta under färg- eller zinkskiktet. Rapporten behandlar de ovan nämnda metoderna, dess egenskaper och miljöpåverkan samt kostnader för systemen. </p><p>De rostskyddsmetoder som används har alla en negativ påverkan på naturen och hälsan. Hur stor den är beror på vilken sorts beläggning som används. Men man måste också tänka på att de faktiskt skyddar stålet och ökar livslängden och därigenom ger ett bättre resursutnyttjande. </p><p>Att säga hur mycket ett system kostar är inte helt lätt. Dessa kostnader beror på flera saker. Den största skillnaden gör mängden stål, men det beror även på till exempel tjocklek och typ av skikt. </p><p>Resultatet av studien är ett antal tabeller där konstruktörerna själva kan gå in och välja det system som, med tanke på ekonomi och miljöfrågor samt skiktets egenskaper, passar bäst till konstruktionen. Även ett snabbvalssystem har utvecklats där man väljer enbart efter en kategori, till exempel den billigaste eller den starkaste.</p>
123

Underhållsplan för maskinhallarna PM 51, 52 och 53 på Bravikens pappersbruk / Plan of maintenance for machine room PM51, 52 and 53 at Braviken papermill

Söderlund, Erika January 2004 (has links)
<p>I det här arbetet har jag gjort en del av en underhållsplan för maskinhallarna PM 51, PM 52 och PM 53 på Bravikens pappersbruk för en ettårs-, femårs- och tioårsperiod. I underhållsplanen har jag tagit fram var skadan är, vad som är skadat, placeringen, omfattningen av skadan, åtgärderna och kostnadsförslag från NCC och Ivarsson&Brink Byggnads AB. Jag fick även möjligheten att studera Bravikens asfaltering och göra en preliminär underhållsplan för den. Tyvärr fanns inte tid att utarbeta den så den finns endast som en bilaga, se bilaga 3. Underhållsplanen för asfalteringen gjorde jag tillsammans med Peter Winterquist från Skanska Väg. </p><p>För att ta fram dessa data har jag intervjuat sektionscheferna för varje maskinhall eftersom de har ansvaret för fastighetsunderhållet. Jag har även diskuterat med min handledare Anneli Gehlin som är gruppchef för avdelningen bygg och miljö. Fängelset Hall i Södertälje har en mycket utarbetad underhållsplan. Därför gjorde Anneli Gehlin och jag ett studiebesök där för att eventuellt få lite tips och information. Jag har även granskat hur andra industrier har utformat sina underhållsplaner för industrifastigheterna. </p><p>En underhållsplan bör alltid hållas aktuell och måste därför uppdateras kontinuerligt. För att kunna göra en mer utarbetad underhållsplan för maskinhallarna på Bravikens pappersbruk behövs det mera tid. Det är mest problem med golven eftersom de är tungt belastade, de har en felaktig beläggning eller är dåligt underhållna. Dessutom täpps dräneringen på taken igen fort. Ett förslag vore att någon kontrollerar golven på varje plan i varje byggnad samt dräneringen på alla tak kontinuerligt eftersom det är mest problem där. Men även hela byggnaderna måste ses över med jämna mellanrum för att kunna hålla underhållsplanen aktuell. Det som ska kontrolleras är golv, dilatationsfogar, fundament, pelare, väggar, dörrar, fönster, tak och fasader. </p><p>För att få ett bra underhåll på fastigheterna på Bravikens pappersbruk måste den här underhållsplanen utarbetas mer. Underhållsplanen bör också vara kopplad till en databas för att lättare få information om byggnaden, lättare att bearbeta underhållsplanen samt att underhållskostnaderna kan hållas nere men även för uppföljning av fastigheternas status och kostnader.</p>
124

A Multi-Criteria Decision-Making Method for Solar Building Design

Andresen, Inger January 2000 (has links)
<p>The background for this thesis is based on the assumption that the success of solar buildings relies on the assessment and integration of all the different design objectives, called criteria. These criteria are often quite complicated to deal with (e.g. environmental loading) and may be conflicting. The different design issues and the many different available energy technologies call for different areas of expertise to be involved in the design of solar buildings. This makes it difficult to evaluate the overall “goodness” of a proposed design solution. Also, the communication between design professionals and the client becomes complicated.</p><p>The goal of this work was therefore to produce a means for the design team and clients to be able to better understand and handle holistic solar design. A first hypothesis was that a structured approach for evaluating design alternatives might be a means to this end.</p><p>In order to specify an approach that would fit into the building design process, an analysis of design process theory and building design practice was carried out (chapter 2). Also, special solar design issues were investigated. This analysis resulted in the following conclusions:</p><p>· Most building design processes start out with no clearly defined goals or criteria of success. The design criteria are refined and discovered through evaluation and feedback on alternative design proposals.</p><p>· Design involves a lot of subjective value judgements, and decisions are often based on experience, “gut feeling”, or intuition. Design options are evaluated based on quantitative and qualitative performance measures. There exists no objective optimal design solution.</p><p>· It is possible to identify some main activities that are common to most design processes. These are categorized into 4 main tasks: problem formulation, generation of alternatives, performance prediction and evaluation. The activities are very much overlapping and dependent on each other.</p><p>· Decision-making in design happens mainly through evaluation of proposed design solutions.</p>
125

Heat transfer in window frames with internal cavities

Gustavsen, Arild January 2001 (has links)
<p>Heat transfer in window frames with internal air cavities is studied in this thesis. Investigations focus on two- and three-dimensional natural convection effects inside air cavities, the dependence of the emissivity on the thermal transmittance, and the emissivity of anodized and untreated aluminum profiles. The investigations are mostly conducted on window frames which are the same size as real frames found in residential buildings.</p><p>Numerical and experimental investigations were performed to study the effectiveness of one commercial Computational Fluid Dynamics (CFD) program for simulating combined natural convection and heat transfer in simple three-dimensional window frames with internal air cavities. The accuracy of the conjugate CFD simulations was evaluated by comparing results for surface temperature on the warm side of the specimens to results from experiments that use infrared (IR) thermography to map surface temperatures during steady-state thermal tests. In general, there was good agreement between the simulations and experiments. </p><p>Two-dimensional computational fluid dynamics and conduction simulations are performed to study the difference between treating air cavities as a fluid and as a solid when calculating the thermal transmittance of window frames. The simulations show that traditional software codes, simulating only conduction and using equivalent conductivities for the air cavities, give U- values that compare well with results from fluid flow simulations. The difference between the two models are mostly limited to the temperature distribution inside air cavities. It is also found that cavities with an interconnection less than about 7 mm can be treated as separate cavities. </p><p>Three-dimensional natural convection effects in simple and custom-made PVC and thermally broken aluminum window frames with one open internal cavity were studied, with the use of CFD simulations and thermography experiments. Focus was put on corner effects and heat transfer rates. From the results it appears that the thermal transmittance of a four-sided section can be found by calculating the average of the thermal transmittance of the respective single horizontal and vertical sections. In addition, it was found that two-dimensinal conduction heat transfer simulation software agrees well with tree-dimensional CFD simulations if the natural convection correlations used for the internal cavities are correct. </p><p>Numerical studies were done with natural convection in three-dimensional cavities with a high vertical aspect ratio and a low horizontal aspect ratio. The cavities studied had vertical aspect ratios of 20, 40, and 80 and horizontal aspect ratios ranging from 0,2 to 5. It was shown that three-dimensional cavities with a horizontal aspect ratio larger than five can be considered to be a two-dimensional cavity to within 4 % when considering heat transfer rates. Nusselt number correlations for the different horizontal aspect ratios are presented for cavities with vertical aspect ratios of 20 and 40. Complex multicellular flow was studied for the case where the vertical and horizontal aspect ratios were 40 and 2, respectively.</p><p>Experimental studies included the normal spectral and total emissivity of specimens from six meter long untreated and anodized aluminum profiles. Specimens facing the internal cavities (thermal break cavity and all aluminum cavity) were measured. Some masking tapes often used in hot box experiments were also measured. The normal total emissivity was found to be is fairly constant (between 0.834 and 0.856) for exterior parts of the anodized profile and for surfaces facing the thermal break cavity. The normal total emissivity of the all-aluminum internal cavities was found to vary between 0.055 and 0.82. The experiments were performed with a Fourier transform infrared spectrometer in the wavelength interval from 4.5 to 40 μm.</p>
126

Statistical modelling of pipe failures in water networks

Røstum, Jon January 2000 (has links)
<p>This thesis presents an evaluation of statistical methods for modelling pipe failures for each individual pipe in a water distribution network. This thesis introduces the Non Homogeneous Poisson Process (NHPP) with covariates (i.e. explanatory variables) as an appropriate method for modelling pipe failures in water networks. As part of this research, a computer program has been developed that estimates the parameters in the NHPP (“Power law” model). The results from this NHPP model are compared to the results obtained from a modified Weibull Proportional Hazards Model (PHM), where the hazard function is allowed to continue beyond the pipe’s first failure. The models are applied in a case study using data for the water distribution network in Trondheim, Norway.</p><p>The statistical models have been calibrated, verified and used to predict failures for both networks (i.e. group of pipes) and individual pipes. Covariates that have a significant influence on the rate of occurrence of failures (ROCOF) are documented. Based on the results from the case study, NHPP is recommend over the Weibull PHM for modelling failures in water networks.</p><p>The output from the statistical models can be used for a variety of purposes in water network management. In the long term the models can be used to estimate future budget needs for rehabilitation. In the short term the models can be used to define candidates for replacement based on poor structural condition. Information about failure intensity is also required for carrying out network reliability analysis. For this purpose reliability data for each individual pipe is required, which is exactly what the predictive models described in this thesis provide.</p>
127

Hard Rock Tunnel Boring

Bruland, Amund January 2000 (has links)
<p>The main purpose of the thesis work has been to improve the existing prediction models and to provide a toolbox for the TBM tunnelling industry (project owners, consultants, contractors, manufacturers, etc.) to be used through all phases of a project:</p><p>• Preliminary and feasibility studies</p><p>• Project design and optimisation</p><p>• Site investigations</p><p>• Tendering and contract</p><p>• Construction</p><p>• Possible disputes or claims.</p><p>The various reports of the thesis treat various subjects of TBM tunnelling. Combined with other estimation models published in the Project Report Series from the Department of Building and Construction Engineering, the reports of the thesis provides a reliable and practical tool to be used for:</p><p>• Estimating net penetration rate and cutter life</p><p>• Estimating construction time and costs, including risk or uncertainty</p><p>• Assessing risk with regard to deviation or variation in estimated rock mass boreability, machine parameters and tunnelling performance</p><p>• Designing auxiliary systems such as ventilation, muck transport, etc.</p><p>• Establishing and managing price regulation in contracts</p><p>• Verifying machine performance</p><p>• Back-mapping and verification of the geological conditions</p><p>• Collecting, normalising and analysing of rock samples, machine performance data and cutter wear data.</p><p>The thesis work has not been focused on basic principles, theoretical modelling or laboratory experiments of rock cutting with disc cutters, although observations and results from field studies are presented and analysed in [11]. Several other researchers and institutions have covered those topics. To be mentioned here is the prominent and comprehensive research done at Colorado School of Mines in the USA and at Luleå University of Technology in Sweden. Both institutions have a series of publications ranging over three decades in this area.</p> / This thesis consists of 10 volumes. Only volume one is available for download. See http://www.tunnel.no/ for more information or contact the author: amund.bruland at ntnu.no
128

A Multi-Criteria Decision-Making Method for Solar Building Design

Andresen, Inger January 2000 (has links)
The background for this thesis is based on the assumption that the success of solar buildings relies on the assessment and integration of all the different design objectives, called criteria. These criteria are often quite complicated to deal with (e.g. environmental loading) and may be conflicting. The different design issues and the many different available energy technologies call for different areas of expertise to be involved in the design of solar buildings. This makes it difficult to evaluate the overall “goodness” of a proposed design solution. Also, the communication between design professionals and the client becomes complicated. The goal of this work was therefore to produce a means for the design team and clients to be able to better understand and handle holistic solar design. A first hypothesis was that a structured approach for evaluating design alternatives might be a means to this end. In order to specify an approach that would fit into the building design process, an analysis of design process theory and building design practice was carried out (chapter 2). Also, special solar design issues were investigated. This analysis resulted in the following conclusions: · Most building design processes start out with no clearly defined goals or criteria of success. The design criteria are refined and discovered through evaluation and feedback on alternative design proposals. · Design involves a lot of subjective value judgements, and decisions are often based on experience, “gut feeling”, or intuition. Design options are evaluated based on quantitative and qualitative performance measures. There exists no objective optimal design solution. · It is possible to identify some main activities that are common to most design processes. These are categorized into 4 main tasks: problem formulation, generation of alternatives, performance prediction and evaluation. The activities are very much overlapping and dependent on each other. · Decision-making in design happens mainly through evaluation of proposed design solutions.
129

Statistical modelling of pipe failures in water networks

Røstum, Jon January 2000 (has links)
This thesis presents an evaluation of statistical methods for modelling pipe failures for each individual pipe in a water distribution network. This thesis introduces the Non Homogeneous Poisson Process (NHPP) with covariates (i.e. explanatory variables) as an appropriate method for modelling pipe failures in water networks. As part of this research, a computer program has been developed that estimates the parameters in the NHPP (“Power law” model). The results from this NHPP model are compared to the results obtained from a modified Weibull Proportional Hazards Model (PHM), where the hazard function is allowed to continue beyond the pipe’s first failure. The models are applied in a case study using data for the water distribution network in Trondheim, Norway. The statistical models have been calibrated, verified and used to predict failures for both networks (i.e. group of pipes) and individual pipes. Covariates that have a significant influence on the rate of occurrence of failures (ROCOF) are documented. Based on the results from the case study, NHPP is recommend over the Weibull PHM for modelling failures in water networks. The output from the statistical models can be used for a variety of purposes in water network management. In the long term the models can be used to estimate future budget needs for rehabilitation. In the short term the models can be used to define candidates for replacement based on poor structural condition. Information about failure intensity is also required for carrying out network reliability analysis. For this purpose reliability data for each individual pipe is required, which is exactly what the predictive models described in this thesis provide.
130

Hard Rock Tunnel Boring

Bruland, Amund January 2000 (has links)
The main purpose of the thesis work has been to improve the existing prediction models and to provide a toolbox for the TBM tunnelling industry (project owners, consultants, contractors, manufacturers, etc.) to be used through all phases of a project: • Preliminary and feasibility studies • Project design and optimisation • Site investigations • Tendering and contract • Construction • Possible disputes or claims. The various reports of the thesis treat various subjects of TBM tunnelling. Combined with other estimation models published in the Project Report Series from the Department of Building and Construction Engineering, the reports of the thesis provides a reliable and practical tool to be used for: • Estimating net penetration rate and cutter life • Estimating construction time and costs, including risk or uncertainty • Assessing risk with regard to deviation or variation in estimated rock mass boreability, machine parameters and tunnelling performance • Designing auxiliary systems such as ventilation, muck transport, etc. • Establishing and managing price regulation in contracts • Verifying machine performance • Back-mapping and verification of the geological conditions • Collecting, normalising and analysing of rock samples, machine performance data and cutter wear data. The thesis work has not been focused on basic principles, theoretical modelling or laboratory experiments of rock cutting with disc cutters, although observations and results from field studies are presented and analysed in [11]. Several other researchers and institutions have covered those topics. To be mentioned here is the prominent and comprehensive research done at Colorado School of Mines in the USA and at Luleå University of Technology in Sweden. Both institutions have a series of publications ranging over three decades in this area. / This thesis consists of 10 volumes. Only volume one is available for download. See http://www.tunnel.no/ for more information or contact the author: amund.bruland at ntnu.no

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