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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.
41

Design of an Earthquake Proof One Family House : A house in alternative construction material, made for slum areas in Medellin, Colombia

Fabisch, Anna, Karlsson, Anders January 2007 (has links)
<p>One of mankind’s most important needs is the need for shelter. All around the world people live in lack of this basic need. Colombia is a South American country heavily burdened by civil war for many years. This has led to that many people have moved to the larger cities with large slum areas and bad living conditions. This thesis is aiming to give a solution to the problem with bad housing and it is performed in cooperation with Ankarstiftelsen. Ankarstiftelsen is a Swedish charity organisation that works with the suffering people in various places in Colombia.</p><p>This thesis examines the possibility to build a house in a sandwich technique with a core of rigid plastic foam and a skin material of fibre reinforced plastic. The construction should be as easy as possible to manufacture, and the construction is also intended to be self carrying. The final proposition is to build the house using polyurethane rigid foam as the core, and a glass fibre reinforced polyester as the skin. This combination combines good mechanical behaviour with a relatively low price.</p><p>Tests have been performed to evaluate the constructions ability to withstand some basic loads, with the help of computer aided engineering. The program that has been used to create a model is ProEngineer, and the application ProMechanica has been used to perform the analysis. The loads that have been tested are: gravity loads, wind loads, maintenance loads and earthquake loads.  Colombia is located in the so called Pacific Ring of Fire, where earthquakes are a bitter reality.  The Colombian building code is, as a result of this, much focused on the issue of earthquake safety. The Colombian building code has been used in order to create reliable earthquake testing models.</p><p>The authors come to the conclusion that the house is possible to build with the given data. However, further investigations regarding manufacturing techniques and practical tests have to be made before the house can be built in reality.</p>
42

Byggavfall vid nybyggnation : En studie om Projekt Hammarby Sjöstad

vilhu, daniel, Säfström, Urban January 2008 (has links)
Arbetet har skrivits på uppdrag av Exploateringskontoret i Stockholm och innefattar sexbyggnadsentreprenörer som alla bygger i området Hammarby Sjöstad där studiengenomförts. Tillsammans bygger de totalt 1126 stycken lägenheter, samt fem styckenbutiker, sex lokaler och ett dagis. Utöver detta tillkommer även två garage vars avfall ärinräknat i statistiken.Arbetet har gått ut på att undersöka hur mycket byggavfall som bildas per nyproduceradlägenhet, varför det skapas samt när i byggskedet detta sker. Kostnaderna för detta skaäven beräknas och hänsyn ska tas till inköpskostnader av det material som blir till avfallsamt avfallsentreprenörernas efterhanteringsersättning. Grunden till frågeställningen ovanbottnar i indikationer som getts från diverse byggnadsentreprenörer som menat att detbildas cirka två ton avfall per nyproducerad lägenhet.Syftet är att detta ska ge underlag för att på sikt skapa bättre rutiner för projektering ochproduktion av byggnader som möjliggör en reducering av byggavfallet, samt även för attbidra till en större medvetenhet kring avfallssorteringen hos byggarbetare ochbyggnadsentreprenörer. Rapporten bygger på personliga intervjuer, telefonintervjuer ochavfallsstatistik från de medverkande byggnadsentreprenörerna. Grova antagandenbaserade på åsikter från personer med insyn i branschen har i flera fall fått göras.Resultatet baseras på ett genomsnitt av samtliga byggnadsentreprenörers avfallsstatistikoch visar på att det bildas cirka tre och ett halvt ton avfall per nyproducerad lägenhet. Detmesta av avfallet börjar uppstå strax efter halvvägs in i byggskedet och består mestadelsav avfallsfraktionerna Osorterat och Brännbart.Uppgiften att ta reda på orsaken till avfallets uppkomst visade sig vara oss övermäktigeftersom de tidsresurser vi haft tillgodo inte har varit tillräckliga. Istället skapades ettavfallsdiagram med de ingående avfallsfraktionerna uppdelade. Detta diagram löperparallellt med en framtagen generell tidsplan för byggskedet. Det går därför att utläsa vari byggskedet arbetet befinner sig när en viss typ av avfall bildas. För att få mer detaljeradesvar är denna rapport en bra grund till vidare studier i bland annat denna fråga. / hammarby sjöstad
43

Bridge Life Cycle Cost Optimization : Analysis, Evaluation & Implementation / Bridge LCC

Safi, Mohammed January 2009 (has links)
<p>In infrastructure construction projects especially bridge investments, the most critical decisions that significantly affect the whole bridge LCC are the early stages decisions. Clearly, it's more beneficial to correctly choose the optimum bridge than to choose the optimum construction or repair method.</p><p>The ability of a bridge to provide service over time demands appropriate maintenance by the agency. Thus the investment decision should consider not only the initial activity that creates a public good, but also all future activities that will be required to keep that investment available to the public.</p><p>This research is aiming for bridge sustainability, enhance the bridge related decision making, and facilitate the usage of the bridge related feedbacks. The development of a reliable and usable computer tool for bridge LCC & LCA evaluation is the main target.</p><p>Toward the main goal, many steps were fulfilled. A unique integrated Bridge LCC evaluation methodology was developed. Two systematic evaluation ways were developed, one for bridge user cost and one for the bridge aesthetical and cultural value. To put these two systematic ways in practice, two preliminary computer programs were developed for this purpose. Today and future works are focusing on developing methodology and preliminary computer tool for bridge agency cost as well as the bridge LCA evaluation. KTH unique LCC evaluation system will enable the decision makers to correctly choose the optimum bridge in the early stages decision making phases as well as any later on reparation method.</p> / ETSI
44

Road Safety Development Index : Theory, Philosophy and Practice

Al-Haji, Ghazwan January 2007 (has links)
This dissertation develops, presents and tests a new international tool, the so-called Road Safety Development Index (RSDI), which indicates in a comprehensive and easy way the severity of the road safety situation in a specific country and/or in comparison with other countries. There are three pillars of outcomes involved in the framework of RSDI. One pillar is the People focus (road user behaviour). The second is the System focus (safer vehicles, safer roads, enforcement, management, etc). The third is the Product focus in terms of accident death rates. This thesis analyses each of these pillars. In addition, RSDI links the key national practices of road safety to each other and to the end-results (accident death rates). The study suggests a master-list of performance indicators to be implemented for assessing road safety level in a country and for RSDI building. Based on the “master-list”, a short key list of performance indicators is chosen and classified into two primary categories that correspond to two groups of countries: LMCs “Less Motorised Countries” and HMCs “Highly Motorised Countries”. RSDI aggregates the key performance indicators into one single quantitative value (composite index). Four main objective and subjective approaches are used to calculate RSDI and determine which one is the best. One approach uses equal weights for all indicators and countries, whereas the other approaches give different weights depending on the importance of indicators. Two empirical studies were carried out, in different parts of the world, to determine the applicability of this tool in real world applications. The first empirical study comes from eight European countries (HMCs). The second empirical study comes from five Southeast Asian countries (LMCs). The RSDI results from this study indicate a remarkable difference between the selected countries even at the same level of motorisation and/or with close accident death rates. The unavailability of comparable and useful data are problems for deeper analysis of RSDI, especially the index should be as relevant as possible for different parts of the world. The empirical and theoretical assessments prove that RSDI can give a broader picture of the whole road safety situation in a country compared to the traditional models and can offer a simple and easily understandable tool to national policy makers and public. / Denna avhandling utvecklar, presenterar och testar ett nytt internationellt verktyg, det så kallade Road Safety Development Index (RSDI), vilket på ett begripligt och lättillgängligt sätt beskriver trafiksäkerhetsläget i ett visst land jämfört med andra länder. Resultatet av RSDI utgörs av tre grundpelare. Den första pelaren är Fokus på människor (vägtrafikbeteende). Den andra är Fokus på systemet (säkrare fordon, säkrare vägar, beivrande, management, osv). Den tredje pelaren är Fokus på produkten med avseende på antal döda per fordon och per invånare. Arbetet analyserar var och en av dessa tre pelare. RSDI kopplar dessutom samman de viktigaste nationella praxisarna och erfarenheterna med varandra och till slutresultaten (antal dödsfall). Studien föreslår en lista med de viktigaste indikatorerna på hur olika länder vidtar åtgärder för trafiksäkerheten. Grundat på denna “master-lista” kan en kort lista med de viktigaste indikatorerna skapas och klassificeras i två huvudkategorier för två typer av länder: LMC “länder med låg andel fordon” och HMC “länder med hög andel fordon”. RSDI aggregerar de viktigaste performance-indikatorerna till ett enda kvantitativt mått (ett sammansatt index). Fyra olika objektiva och subjektiva huvudangreppssätt används för att beräkna RSDI och bestämma vilket av dem som är det bästa. En metod använder sig av lika stora vikter för alla indikatorer och länder, medan en annan metod ger olika vikter beroende på indikatorernas betydelse. Två empiriska studier genomfördes i olika delar av världen för att bestämma tillämpligheten av detta verktyg i verkliga situationer. Den första empiriska studien kommer från åtta länder i Europa (HMC-länder). Den andra empiriska studien har gjorts i fem länder i Sydostasien (LMC-länder). Resultaten från detta RSDI tyder på en anmärkningsvärd skillnad mellan de valda länderna, också om andelen bilägare och/eller andra variabler för trafiksäkerhet hålls konstanta. Bristen på jämförbara och användbara data medför problem vid en djupare analys av RSDI för olika delar av världen. De empiriska och teoretiska skattningarna visar att RSDI kan ge en bredare bild av hela trafiksäkerhetssituationen i ett land jämfört med traditionella modeller och kan erbjuda ett enkelt och lättförståeligt verktyg för de nationella beslutsfattarna liksom för allmänheten.
45

Spatial systems af producers of meaning : the idea of kowledge in three public libraries

Koch, Daniel January 2004 (has links)
No description available.
46

Aspects of Static Multi-Class Traffic equilibria under Congestion Pricing

Lindberg, Per Olov January 2010 (has links)
<p>Congestion charging is a now accepted means of influencing traffic to behave in a more socio-economic optimal way, like e.g. in the Stockholm project. Already early work, in the 1920’s, showed that road use can be inefficient due externalities, i.e. that users don’t experience their own (negative) effect on other users: an extra car on a traffic link causes delays for other cars, but the driver himself does not experience this cost.In the 1950’s it was further shown - for a congested road network with homogeneous users – that if each user is charged a toll equal to the total value of time loss incurred on other users of the network, then -if we have fixed travel demand - this will induce an equilibrium that is system optimal in the sense that the total cost of network usage is minimal (assuming that all users have fixed and identical time values).  But toll charges need to be levied in monetary units, and different travelers have different values of time. Therefore, to account for the effects of tolls, and to be able to compute equilibria, one needs to introduce different user classes, differing in their time values.</p><p>In this thesis, consisting of four papers, we study congestion pricing of road networks with users differing only in their time values. In particular, we analyze marginal social cost (MSC) pricing, a tolling scheme that charges each user a penalty corresponding to the value of the delays inflicted on other users, as well as its implementation through fixed tolls.</p><p>Paper III contains the main theoretical work of the thesis. In that paper we show that the variational inequalities characterizing the equilibria in question can be stated in symmetric or non-symmetric forms. The symmetric forms correspond to optimization problems, convex in the fixed-toll case and non-convex in the MSC case, which hence may have multiple equilibria. The objective of the latter problem is the total value of travel time, which thus is minimized at the global optima of that problem. Implementing close-to-optimal MSC tolls as fixed tolls leads to equilibria with possibly non-unique class specific flows, but with identical close-to-optimal values of the total value of travel time. Finally we give an adaptation, to the MSC setting, of the Frank-Wolfe algorithm, which is further applied to some test cases, including Stockholm.</p><p>Paper I is an early application using Frank-Wolfe, after having realized the possibility to symmetrize the problem.</p><p>Paper II gives a convexification of non-convex equilibrium problem for MSC tolls. We have used these convexifications to compute lower bounds when computing equilibria.</p><p>Paper IV is a short note commenting some flaws in two papers by Dial on MSC tolls.</p>
47

Elasticitetsmodulen i en kalkstabiliserad vägterrass : en fältstudie / The elastic modulus in a lime stabilized subgrade : a study of the spatial variability

Olofsson Augustsson, Erik January 2010 (has links)
<p>Stabilization of subgrade is an internationally common technique to improve the characteristics of a soft soil. Improving the stiffness and bearing capacity of the subgrade enables the pavement to be designed with reduced depths of subbase and basecourse aggregates. This makes the stabilization technique both economically and environmentally interesting. Both natural and stabilized soils have high inherent property variability that should be considered when the characteristic value is derived. By analyzing the spatial variability in stabilized and natural subgrades it is possible get the parameters needed for reliability–based modeling of soil properties. I order to do so, three statistical parameters need to be evaluated, i.e. the mean, the variance and the scale of fluctuation, which is the distance within which soil properties show relatively strong correlation.</p><p>The objective of this thesis is to study different devises for determining the elastic modulus of subgrade and to study the spatial variability of the elastic modulus. With knowledge of this it is possible to optimize the testing. The different devises used in the field investigations was the light weight deflectometer (LWD), surface seismic and static plate loading. The different devices were used because they take measurements at different load- and strain levels.</p><p>Another aim was to investigate correlations between moduli determined by the different devices. This thesis is a part of a research project at Skanska about subgrade stabilization. The field studies were performed in Tygelsjö, south of Malmö, and the soil type was claytill. Two test areas, each 7x15 m, were stabilized with 6 % respective 4 % hydrated lime and two test areas, each 4x15 m, were left unstabilized. Totally 133 test points were investigated with the LWD and surface seismic and 11 static plate load tests were performed.</p><p>With geostatistical analyses of the experimental results the scale of fluctuation with respect to the elastic modulus has been evaluated to approximately 1,3 m. That means only points within 1,3 m reveal relative strong correlation. In practice this means that subsidence due to less stiffness in the stabilized subgrade will not be extensive in the surface. Therefore it’s not economically rational to design the pavement with respect to small areas with low stiffness in the subgrade.</p><p>Comparison between the LWD and the static plate load test showed that ____ is on average 2 times greater than ___. No correlations with the surface seismic were found. One influencing factor on the LWD measurements was the drop height. ____ decreased with increasing drop height but only on the unstabilized subgrade.</p><p>This thesis also shows how the characteristic value of the elastic modulus could be evaluated with statistical methods where the evaluation will depend on the number of measurements, the variability of the measurements and the variance reduction factor which in turn depends on the scale of fluctuation and the size of the mechanical system. This type of evaluation could be used as basis for reliability based design and design according to the observational method according to Eurocode 7.</p> / QC 20100706
48

Mer park i tätare stad

Ståhle, Alexander January 2005 (has links)
<p>The prevailing urban planning strategy in the 21st century in many European cities is urbanisa-tion by densification. The strategy, which has obvious consequences for green and open space, has commonly been described as “Compact city” or “Smart growth”. Densification has mainly been initiated by large building companies, often in conflict with local lobby groups with strong social capital. This has frequently led to deadlocks in planning, especially concerning green space exploitation. This paper suggests new tools for understanding and measuring how urban structuring affects open space accessibility, not only because urban structure distributes open space to people, it also creates users and stakeholders.</p><p>Since the 1950:s Swedish urban planning has been led by normative open space guidelines developed by research and national ministries, guidelines that are still present but has lost in power. Generally these guidelines are based on either density, i.e. sqm green space/person within a defined area, or range, i.e. maximum metric distance to a minimum park size. Planning practice has essentially dealt with size and qualities, often confusing, in micro economic terms, use value and non-use value (e.g. the “ecological”). This paper introduces new ways of integrating use value (sociotop) and orientation (axial lines) into new measures of open space accessibility. A new GIS-application “The Place Syntax Tool” (PST), developed within the research project, makes it possible to calculate the ‘topological’ open space accessibility from every place (address or plot) in an urban area, current or planned. ‘Topological’ accessibility analyses handles the “modified area unit problem” (MAUP) discussed in geography.</p><p>A questionnaire from 2001 (TEMO) states that, citizens in some dense inner-city-districts experience higher park and nature accessibility than in some low-density “green” sub-urbs in Stockholm. This peculiar result was the starting point of testing old and new measures in ten different city districts, using PST. The conclusion is that a new measure, which take range, orientation, green space size and number of use values into account, correlates consid-erably better to the questionnaire (R2=0,75 p<0,001), than any conventional measures. It shows that the 19th century “deformed” inner city grid with defined urban parks connected by green boulevards more effectively distributes open space to many citizens compared with the “interrupted” grid and segregated green structure of the post war “modernist” suburbs.</p><p>Another finding is that axial lines seem to capture movement to and within open space better than any metric measure. Correlation was found when comparing observed pedes-trian flow and calculated population accessibility (Södermalm dij=3, R2=0,682, p<0,001; Hög-dalen dij=6, R2=0,442, p<0,001). Correlation was also found when comparing a questionnaire asking “How often do you go to your favourite green area?” (USK 2002) and axial line distance between all addresses in the study areas and the closest green area (R2=0,77, p=0,018). These results can also be explained by the Space syntax integration analysis which shows that the green spaces in the inner city grid is much more integrated than in the post war suburbs. This means that orientation plays a big part in determining if, and how often people visit open spaces.</p><p>Consequently, better measures could promote understanding of open space planning as an asset to city development, help overcome the deadlock in densification planning and change the common opinion of open space and “green” from a static to a dynamic urban entity.</p>
49

Flexibla modullägenheter

Johansson, Tina, Håkansson, Pernilla January 2009 (has links)
<p>The following report is based on the fact that we today aren´t building enough small apartments with the right of tenancy around the country. Numbers show that many young people and students will be in need of an apartment in the upcoming years. Because we already have a lack of small apartments in many of the student cities we have to find a solution today. Could module apartments be the solution?</p><p>The report is a part of a project, which with the help of industrial building and its prerequisites, smaller apartments in module form has been planned. The apartments, are as far as possible, standardized but concludes a flexibility in the shaping which creates possibilities for different solutions. The apartments can be combined in different ways for use at different sites. In the project the quarter Järnbäraren has been used as a plot example, where the apartments have been used as student housing.</p><p>The report describes the theoretical reasons to why you should use industrial building and what it takes for it to be a successful concept. It also contains analysis of earlier projects which can be compared with this one. The report also includes historical aspects on the development of industrial buildings during the 20th century and how the housing market has changed over the past years.</p><p>The report shows the thoughts and speculations that lies behind the decisions which have been made during the project. It also works as a description of the prerequisites in the project. Most prerequisites came from the company Moelven, who there have been a cooperation with since the start of the project.</p><p>The result has shown that it is possible to develop module apartments with high quality despite standardization and cost conscious thoughts. Since it is the technical parts in the apartment that is the biggest cost for the module, you’re able to increase dwelling space improve the quality in the apartment without the rent being raised and be absurd for example students.</p>
50

Kv. Vattenspegelnsödra Munksjön, Jönköping : Hur kan ett attraktivt bostadskvarter utformas vidsödra Munksjön?

Nyman, Andreas, Samano, Dorin, Seifeddine, Mahmoud January 2009 (has links)
<p>The purpose is to understand the planning process for residential buildings and toinvestigate the consequences of the choices made in the process. The project will alsoprovide broader knowledge in the design and development under the current law andpractice.The goal is to present a proposal on how a city near the site where water can bedesigned from a sustainable perspective. How can a residential neighborhood be anenvironmentally sound and sustainable region? New systems and techniques havebeen presented previously in terms of sustainable environments and these are intendedof being used in the project Quarter Water-mirror.The project has been implemented on the computer program ArchiCAD in whichdrawings and visualizations have been carried out. These drawings are included asannexes to the report.For information, calculations and drawings, laws for physical planning and Swedishstandard have been followed.Residential buildings have been designed on a site, which is 2, 5 hectares. This area isexploited to a large extent, have generous space and environmentally friendlyachievements. The sustainable development of the area is supposed to contribute tolong-term management. To create an attractive and interesting environment, a channelhas been incorporated into the field.In the planning has availability, guest/ private parking, infrastructure and in the land,the farm formations, water and solar studies taken into account where the Planningand Building Act has been a starting point.Apartments have been presented with regard to the functioning, transparency andlight. When these factors were crucial in the case of a well-resolved data.The investigations made that refined solutions, including waste disposal, diversion ofwater, etc. existed. These methods will not necessarily be used in Quarter Watermirrorbecause nothing is elucidated. However, these solutions are good practice togive the area a sustainable environment.</p>

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