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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.
71

En analys av Eurokod 1990 : - användarråd, jämförelser samt en intervjuundersökning

Wennström, Lina January 2008 (has links)
The EN Eurocodes are a new series of standards for construction design in Europe. The development of these codes started originally in 1975 and in present time the progressing work is at the national calibration stage. The goal is to create a common standard for the design of buildings and other civil engineering works throughout Europe and beyond. The purpose is to increase the free circulation of construction products and engineering services. Since the transition to the new standards is getting closer, the constructing engineers and companies will soon stand before great changes. This is why Kadesjös Ingenjörsbyrå AB asked me to do an analysis of the first part of the new standard, i.e. Eurocode 1990, and look at the differences among the existing standards in Sweden and the Eurocodes. The result of this is summarized not only in the report but also in a “User’s manual” which is presented in appendix 1 attached to the report. A limited study of the environmental effects of the transition to Eurocode EN 1990 has also been done. By comparing design calculations of a normal beam in three different materials, steel, concrete and glued laminated timber, one can, for instance, get a general view of how the differences of the two standards affect the required quantity of material. To get an insight of the different opinions that might exist concerning the new standard, a survey based on interviews of a few constructional engineers has been done. There was also discussed if any, and in that case what kind of preparations constructors and design companies are performing to be well prepared when the transition comes.
72

Framework para suporte à verificação automatizada de requisitos regulamentares em projetos hospitalares

Soliman Junior, João January 2018 (has links)
Empreendimentos hospitalares são reconhecidos pela complexidade que está associada a todas as fases de seu ciclo de vida: projeto, construção e operação. Os projetos da saúde são altamente influenciados por regulamentações locais. Estes conjuntos de códigos e legislações contém informações prescritivas e são importantes ao projeto, uma vez que as especificações são, usualmente, definidas de acordo com os critérios neles contidos. Ao longo do processo de desenvolvimento de produto, as especificações devem ser verificadas frente aos requisitos extraídos destas regulamentações. Este processo, se realizado manualmente, tende a ser demorado e propenso a erros. Tentativas de desenvolvimento de sistemas de verificação automatizada não se mostraram completamente satisfatórias. Muitos dos problemas estão relacionados à forma como novas abordagens são concebidas, muitas vezes desenvolvidas de acordo com métodos codificados e fragmentados, e à tipologia de informação que está nas normas e regulamentações. A abordagem metodológica utilizada nesta pesquisa foi a Design Science Research. Como artefato, foi desenvolvido um framework com base na abordagem semântica, para fornecer suporte ao desenvolvimento de sistemas de verificação automatizada, com ênfase em requisitos regulamentares no contexto de projetos de edificações hospitalares. As principais contribuições teóricas deste estudo, portanto, estão relacionadas às taxonomias e às transformações da informação, bem como às relações entre os constructos utilizados. Os resultados indicam que a natureza das regulamentações possui impacto significativo na possibilidade de tradução em regra lógica parametrizável. Apesar de a automação ser desejável, os resultados deste estudo indicam, ainda, que atualmente nem todos os requisitos podem ser completamente traduzidos em termos de processamento e verificação automatizados. Apesar de este fato diminuir o nível geral de automatização no processo, ele pode trazer benefícios ao contexto de projetos da saúde. O atendimento de alguns dos requisitos depende em um certo grau, em critérios subjetivos, que estão relacionados à interpretação humana e à criatividade. / Healthcare facilities are recognized for the complexity associated to all phases of their lifecycle: design, construction and operation. The design of healthcare projects is highly influenced by local healthcare regulations. These legislations usually contain prescriptive information and play an important role, as design specifications should be defined based on the criteria defined therein. In the design phase, during the product development process, requirements extracted from legal regulations must be verified against design specifications. This process, if done manually, tends to be time consuming and error prone. Attempts to develop automated rule checking systems for healthcare projects have not been fully successful. Most flaws appear to be related to the way new approaches are conceived, being mostly developed according to hard-coded and fragmented approaches, and the typology of information bounded by the regulations. The methodological approach adopted in this investigation was the Design Science Research. The main outcome of this research study is a semantic-based framework, devised to support the development of automated rule checking systems, focused on regulatory requirements of healthcare building design. The main theoretical contributions of this research work are concerned with the taxonomies and information transformation, as well as the relationships among the constructs involved. The results indicate that the nature of regulations have a major impact on the possibility of translating them into logic rules. Even though automation is desirable, the findings of this study also indicate that currently not all requirements can be fully translated into rules for automated processing and checking. Although this decreases the overall degree of automation in the process, this fact may provide benefits to the healthcare context. The fulfillment of some requirements to some extend should rely on subjective criteria, which depends on human interpretation and creativity.
73

Framework para suporte à verificação automatizada de requisitos regulamentares em projetos hospitalares

Soliman Junior, João January 2018 (has links)
Empreendimentos hospitalares são reconhecidos pela complexidade que está associada a todas as fases de seu ciclo de vida: projeto, construção e operação. Os projetos da saúde são altamente influenciados por regulamentações locais. Estes conjuntos de códigos e legislações contém informações prescritivas e são importantes ao projeto, uma vez que as especificações são, usualmente, definidas de acordo com os critérios neles contidos. Ao longo do processo de desenvolvimento de produto, as especificações devem ser verificadas frente aos requisitos extraídos destas regulamentações. Este processo, se realizado manualmente, tende a ser demorado e propenso a erros. Tentativas de desenvolvimento de sistemas de verificação automatizada não se mostraram completamente satisfatórias. Muitos dos problemas estão relacionados à forma como novas abordagens são concebidas, muitas vezes desenvolvidas de acordo com métodos codificados e fragmentados, e à tipologia de informação que está nas normas e regulamentações. A abordagem metodológica utilizada nesta pesquisa foi a Design Science Research. Como artefato, foi desenvolvido um framework com base na abordagem semântica, para fornecer suporte ao desenvolvimento de sistemas de verificação automatizada, com ênfase em requisitos regulamentares no contexto de projetos de edificações hospitalares. As principais contribuições teóricas deste estudo, portanto, estão relacionadas às taxonomias e às transformações da informação, bem como às relações entre os constructos utilizados. Os resultados indicam que a natureza das regulamentações possui impacto significativo na possibilidade de tradução em regra lógica parametrizável. Apesar de a automação ser desejável, os resultados deste estudo indicam, ainda, que atualmente nem todos os requisitos podem ser completamente traduzidos em termos de processamento e verificação automatizados. Apesar de este fato diminuir o nível geral de automatização no processo, ele pode trazer benefícios ao contexto de projetos da saúde. O atendimento de alguns dos requisitos depende em um certo grau, em critérios subjetivos, que estão relacionados à interpretação humana e à criatividade. / Healthcare facilities are recognized for the complexity associated to all phases of their lifecycle: design, construction and operation. The design of healthcare projects is highly influenced by local healthcare regulations. These legislations usually contain prescriptive information and play an important role, as design specifications should be defined based on the criteria defined therein. In the design phase, during the product development process, requirements extracted from legal regulations must be verified against design specifications. This process, if done manually, tends to be time consuming and error prone. Attempts to develop automated rule checking systems for healthcare projects have not been fully successful. Most flaws appear to be related to the way new approaches are conceived, being mostly developed according to hard-coded and fragmented approaches, and the typology of information bounded by the regulations. The methodological approach adopted in this investigation was the Design Science Research. The main outcome of this research study is a semantic-based framework, devised to support the development of automated rule checking systems, focused on regulatory requirements of healthcare building design. The main theoretical contributions of this research work are concerned with the taxonomies and information transformation, as well as the relationships among the constructs involved. The results indicate that the nature of regulations have a major impact on the possibility of translating them into logic rules. Even though automation is desirable, the findings of this study also indicate that currently not all requirements can be fully translated into rules for automated processing and checking. Although this decreases the overall degree of automation in the process, this fact may provide benefits to the healthcare context. The fulfillment of some requirements to some extend should rely on subjective criteria, which depends on human interpretation and creativity.
74

Diretrizes para a gestão de requisitos no processo de projeto de ambientes construídos : um estudo de caso com enfoque nos requisitos ambientais

Pegoraro, Camila January 2010 (has links)
Devido a fatores como o longo tempo de desenvolvimento e a elevada quantidade de clientes envolvidos, existem dificuldades para realizar a gestão dos requisitos dos clientes do processo de projeto de ambientes construídos. Na busca por alternativas para solucionar tais dificuldades, esta pesquisa explora conceitos e práticas de Gestão de Requisitos (GR) provenientes de outras áreas de conhecimento, em especial da engenharia de software (ES). O objetivo da pesquisa é apresentar diretrizes para integrar a GR ao processo de projeto, tendo em vista contribuir com o acompanhamento da evolução e no controle dos requisitos dos clientes. Uma versão preliminar das diretrizes foi desenvolvida com base na revisão bibliográfica e nos resultados de um estudo de caso exploratório. Posteriormente, as mesmas foram aplicadas com ênfase nos requisitos ambientais identificados em um segundo estudo de caso, o qual permitiu o refinamento e a proposta final das diretrizes. Tais diretrizes são formadas por duas premissas e nove atividades. As premissas são condicionantes a serem atendidos pelas empresas para a realização das atividades da GR. As atividades, por sua vez, são desdobramentos das quatro etapas da GR (identificação de requisitos, análise e priorização, especificação e validação) e repetem-se ciclicamente ao longo das fases do processo de projeto, podendo ser implantadas com o apoio de boas práticas. Embora as diretrizes sejam aplicáveis à gestão de quaisquer tipos de requisitos, existem particularidades intrínsecas na gestão de cada tipo (sociais, econômicos e ambientais, por exemplo). No caso desta pesquisa, foi enfatizada a investigação das peculiaridades referentes aos requisitos ambientais identificados no empreendimento do segundo estudo de caso. A principal contribuição teórica desta pesquisa é a proposta de diretrizes para a GR suficientemente generalizáveis para aplicação em diferentes modelos de processo de projeto e diferentes tipos de requisitos. Do ponto de vista prático, os resultados evidenciaram que as diretrizes contribuem para a gestão sistemática dos requisitos, uma atividade que é normalmente realizada de modo informal no processo de projeto. / Long development period and a high number of stakeholders with different demands consist in some of the majors difficulties to be managed along the building design process. This research explores the Requirements Management (RM) concepts and practices from areas as software engineering as an alternative to solve some managerial problems. The aim is to present guidelines to integrate RM in the building design process, viewing the improvement of requirements traceability and control. The guidelines draft was based on literature review and on the results of an exploratory case study. Afterwards the guidelines draft was tested through a second case study, with emphasis on the project environmental requirements. This application promoted the guidelines improvement into their final configuration. The guidelines are based on two premises and nine activities. Premises are conditions which should be accomplished before the activities implementation. The activities are refinements of the four RM steps (requirements elicitation, analysis and prioritization, specification and validation) and they should be cyclically performed through the design process, using adequate good practices. Although guidelines may be useful to the management of any type of requirements, there are particular features to manage each of them (e. g. social, economical environmental). In this research, environmental requirements from the main case study were emphasized. The main theoretical contribution of this research is the proposition of guidelines which are generic enough to be performed through different design process models and different types of requirements. From a practical standpoint, the results indicated that the guidelines have contributed to the systematic RM in design process, an activity that is often informally performed in design process.
75

Diretrizes para a gestão de requisitos no processo de projeto de ambientes construídos : um estudo de caso com enfoque nos requisitos ambientais

Pegoraro, Camila January 2010 (has links)
Devido a fatores como o longo tempo de desenvolvimento e a elevada quantidade de clientes envolvidos, existem dificuldades para realizar a gestão dos requisitos dos clientes do processo de projeto de ambientes construídos. Na busca por alternativas para solucionar tais dificuldades, esta pesquisa explora conceitos e práticas de Gestão de Requisitos (GR) provenientes de outras áreas de conhecimento, em especial da engenharia de software (ES). O objetivo da pesquisa é apresentar diretrizes para integrar a GR ao processo de projeto, tendo em vista contribuir com o acompanhamento da evolução e no controle dos requisitos dos clientes. Uma versão preliminar das diretrizes foi desenvolvida com base na revisão bibliográfica e nos resultados de um estudo de caso exploratório. Posteriormente, as mesmas foram aplicadas com ênfase nos requisitos ambientais identificados em um segundo estudo de caso, o qual permitiu o refinamento e a proposta final das diretrizes. Tais diretrizes são formadas por duas premissas e nove atividades. As premissas são condicionantes a serem atendidos pelas empresas para a realização das atividades da GR. As atividades, por sua vez, são desdobramentos das quatro etapas da GR (identificação de requisitos, análise e priorização, especificação e validação) e repetem-se ciclicamente ao longo das fases do processo de projeto, podendo ser implantadas com o apoio de boas práticas. Embora as diretrizes sejam aplicáveis à gestão de quaisquer tipos de requisitos, existem particularidades intrínsecas na gestão de cada tipo (sociais, econômicos e ambientais, por exemplo). No caso desta pesquisa, foi enfatizada a investigação das peculiaridades referentes aos requisitos ambientais identificados no empreendimento do segundo estudo de caso. A principal contribuição teórica desta pesquisa é a proposta de diretrizes para a GR suficientemente generalizáveis para aplicação em diferentes modelos de processo de projeto e diferentes tipos de requisitos. Do ponto de vista prático, os resultados evidenciaram que as diretrizes contribuem para a gestão sistemática dos requisitos, uma atividade que é normalmente realizada de modo informal no processo de projeto. / Long development period and a high number of stakeholders with different demands consist in some of the majors difficulties to be managed along the building design process. This research explores the Requirements Management (RM) concepts and practices from areas as software engineering as an alternative to solve some managerial problems. The aim is to present guidelines to integrate RM in the building design process, viewing the improvement of requirements traceability and control. The guidelines draft was based on literature review and on the results of an exploratory case study. Afterwards the guidelines draft was tested through a second case study, with emphasis on the project environmental requirements. This application promoted the guidelines improvement into their final configuration. The guidelines are based on two premises and nine activities. Premises are conditions which should be accomplished before the activities implementation. The activities are refinements of the four RM steps (requirements elicitation, analysis and prioritization, specification and validation) and they should be cyclically performed through the design process, using adequate good practices. Although guidelines may be useful to the management of any type of requirements, there are particular features to manage each of them (e. g. social, economical environmental). In this research, environmental requirements from the main case study were emphasized. The main theoretical contribution of this research is the proposition of guidelines which are generic enough to be performed through different design process models and different types of requirements. From a practical standpoint, the results indicated that the guidelines have contributed to the systematic RM in design process, an activity that is often informally performed in design process.
76

Valorisation de l'inertie thermique pour la performance énergétique des bâtiments / Valorization of thermal mass for the energy performances of buildings

Chahwane, Layal 21 October 2011 (has links)
L'inertie thermique constitue un atout essentiel pour stocker l'énergie reçue par le bâtiment et la restituer quand cela est nécessaire : elle permet d'emmagasiner les apports gratuits issus du rayonnement solaire pour réduire les consommations énergétiques liées au chauffage en présence d'une isolation performante. En été, son association à la ventilation nocturne contribue à évacuer l'énergie stockée au cours de la journée limitant ainsi les surchauffes à l'intérieur du bâtiment. Une exploitation optimale de l'inertie passe par une sélection appropriée des matériaux de construction lors de la phase d'avant-projet et par le développement de stratégies visant à exploiter leur capacité de stockage. Les outils de simulation thermique dynamique dont on dispose permettent de modéliser de façon assez précise les transferts de chaleur dans l'enveloppe du bâtiment mais leur niveau de finesse n'est pas nécessairement adapté aux besoins des concepteurs au moment de faire les choix les plus fondamentaux. Néanmoins ils demeurent indispensables non seulement pour la validation de ces choix mais aussi pour le développement de méthodes destinées à améliorer l'exploitation de l'énergie avant de procéder à la réalisation d'un projet. Ce travail a consisté à développer une méthodologie de conception basée sur deux approches complémentaires : la première approche permet de décrire le comportement détaillé du bâtiment à l'aide d'un modèle de simulation dynamique performant développé dans la plateforme SimSPARK qu'on a eu l'occasion de comparer aux mesures expérimentales de la plateforme INCAS. La seconde est basée sur le développement de l'outil simplifié CoSPARK qui à partir de la connaissance de quelques éléments clés, permet de déterminer les caractéristiques appropriées de l'enveloppe pour favoriser la performance énergétique des bâtiments. La dernière partie de ce travail a été consacrée à l'optimisation de stratégies d'une part en activant l'inertie thermique dans le cas d'une ventilation nocturne adaptative pour l'été et d'autre part en réduisant les consommations de chauffage en hiver dans le cas d'un plancher couplé à une installation solaire en utilisant le modèle de référence SimSPARK. / Thermal inertia is a key asset to store energy received by the building and release it when needed : in winter, when used with a good insulation, it can store solar heat gains available during the day (collected via different systems) and restitute them during the night thus reducing energy consumption. In summer, building thermal mass coupled with an efficient night ventilation helps remove the energy stored during the day, which limits overheating periods inside the building during the next day. Optimal use of thermal inertia results from an appropriate selection of building materials during the preliminary design phase and the development of strategies to exploit their storage capacity. Actual thermal simulation tools allow for higher accuracy in heat transfer modeling through the building envelope. However, their level of precision is not necessarily adapted to the needs of designers during the design phase when making the first choices. Nevertheless, they remain indispensable not only for the validation of these choices but also to develop methods to improve the management of the energy prior to the completion of a project. This work aimed to develop a design methodology based on two complementary approaches : the first method uses the accurate building response evaluated using a dynamic simulation model developed in SimSPARK simulation platform that we had the opportunity to compare with experimental measurements on the INCAS platform. The second one consists on using the results of a simplified tool (CoSPARK) to determine, with only few design key elements, the appropriate characteristics of the envelope that optimize the energy performance of the building. The last part of this work exposes some strategies that help take full advantage of the thermal mass inertia ; on one hand, for summer comfort, with the use of an adaptive night ventilation control, and, on the other hand, for winter periods, by reducing heating consumption using a radiant floor heating coupled with a solar system.
77

Bedeutende Planungshilfe für den Bibliotheks- und Archivbau. Der neue DIN-Fachbericht 13

Rabe, Roman 22 December 2009 (has links)
Der DIN-Fachbericht 13 „Bau- und Nutzungsplanung von wissenschaftlichen Bibliotheken“ zählt seit 1988 zu den wichtigsten Planungsinstrumenten für den Bibliotheksbau. Ein DIN-Fachbericht stellt keine verbindliche Norm dar. Seine Aussagen besitzen lediglich empfehlenden Charakter. Trotzdem wurden vor allem die quantitativen Kernaussagen zum Flächenbedarf von Beständen, Nutzerarbeitsplätzen und speziellen Funktionen im DIN-Fachbericht 13 von Trägern, Bauherren und Architekten als Grundlage für die Planung konkreter Projekte weitgehend anerkannt. Die Aussagen des DIN-Fachberichtes haben schon deshalb erheblichen Einfluss auf Bibliotheksplanungen in Deutschland – und sogar darüber hinaus, denn sie werden wegen ihrer Detailliertheit und Vollständigkeit in der internationalen Normenentwicklung geschätzt und als Vorbild betrachtet. Als ambitioniertes Ziel nahm sich das DIN diesmal nicht nur eine Aktualisierung, sondern auch eine Erweiterung um Belange von Öffentlichen Bibliotheken und Archiven vor.
78

How to create affordable and sustainable facilitites for companies / Hur skapas billiga och hållbara lokaler för företag

Persson, Andreas, Holmberg, Daniel January 2016 (has links)
Summary Kruthusen Företagsfastigheter AB is a company that rent industrial facilities, mainly to smaller companies and startup companies. Most of their facilities today are already rented which creates the opportunity to expand and build new facilities. The problem is that the building methods and materials commonly used today will require a rent that is unaffordable for these companies. Therefore a new way of creating these facilities is needed to be able to reduce costs, to allow a lower rent.  In the current facilities big costs are connected with companies’ changing facilities which often require reconstruction or similar. Some needs extra bathrooms, other need a kitchen and a few do not need any of it. Therefore, to save a lot of money on reconstruction a common area will be built where there will be a dressing room with showers, WC and a kitchen. There are many different ways to save energy which also reduces costs. Research has been made to see if there are other alternatives to heat the building. District heating is available in the area where the new facility will be built. District heating is considered a sustainable choice and therefore was selected. Heat losses for the new building were calculated to estimate if it is enough to target operational costs to be able to secure a low rent. The result was that a high amount of the heat losses can be reduced but it is not enough to allow affordable rents. The total cost of the building could not be estimated by us. This is the reason why other measures like common areas cannot be proven to lower the rent to the targeted value. If the concept is affordable will be known when the concept is sent to a construction company for cost estimation. The final building will include a common area in the middle connected with the entrance and 10 industrial facilities for renting that will be 8x13 square meters. To make it easier for the customers a parking lot will be built in front of the building. On the back side every company will have an area for their work-related vehicles. Also a spot for containers will be included for extra storage for each renting company. / Sammanfattning Kruthusen Företagsfastigheter AB är ett företag som hyr ut lokaler till främst mindre och nystartade företag. Idag är nästan alla av deras lokaler redan uthyrda vilket möjliggör utbyggnad av nya lokaler. Problemet med detta är att användning av dagens byggnadsmetoder och material kommer ge en väldigt dyr hyra, som dessa små företag inte kan betala. Därför behövs det nya sätt som fokuserar på att få ner kostnader när dessa typer av lokaler ska byggs, för att få en låg hyra. I dagens lokaler tillkommer stora kostnader i ombyggnader eller liknande när företag byter lokaler. Vissa har behov av extra badrum, andra behöver tillgång till kök och några behöver inte tillgång till något. För att undvika de största kostnaderna i samband med detta kommer en gemensam avdelning byggas där det finns omklädningsrum med dusch, toaletter och kök. Det finns många sätt att spara energi på som också minskar kostnader. En undersökning har gjorts för att se om det finns några andra alternativ till uppvärmning av lokalerna. Fjärrvärme är tillgängligt i det valda området för byggnaden, därför valdes detta som värmekälla då det anses vara ett hållbart alternativ. Värmeförluster beräknades för den nya byggnaden för att uppskatta om det är tillräckligt att fokusera på driftkostnader för att erhålla en låg hyra. Resultatet blev att en väldigt hög andel av värmeförlusterna kunde minskas, men det var inte tillräckligt för att ensamt säkerställa en låg hyra. Den totala kostnaden för byggnaden kunde inte uppskattas av oss. Detta är anledningen till att andra åtgärder som gemensamma utrymmen inte kan bevisas vara tillräckligt för att få en låg hyra. Först när ett byggföretag har gjort sin kostnadsuppskattning kommer det visa sig om konceptet är tillräckligt konstandseffektivt. Den slutgiltiga byggnaden kommer bestå av en gemensam avdelning i mitten sammanlänkat med entrén och 10 industrilokaler i storleken 8x13 meter för uthyrning. För att underlätta för kunder finns det en parkering framför byggnaden. På baksidan finns det utrymme för varje företag att ha sina fordon. Det kommer även finnas utrymme för containrar som extra utrymme för företagen.
79

Livscykelkostnader och upphandling av projekterande konsulter : En analys av upphandlingsdokument / Life-cycle Costs and the Procurement of Building Design Consultants : An Analysis of Procurement Documents

Sjöberg, Anton January 2021 (has links)
För byggnader har drift- och underhållskostnader ofta större ekonomiska konsekvenser än den initiala investeringen och livscykelkostnader (LCC) har i upphandlingslagstiftningen lyfts fram som ett sätt att verka för hållbar upphandling. Med tanke på dessa omständigheter bör det vara intressant för offentliga fastighetsägare att tillämpa arbetssätt där de tidigt i projekten kan överskåda de långsiktiga ekonomiska konsekvenserna av deras val genom att analyser LCC. Genom att analysera textinnehållet i upphandlingsdokument har målet med det här examensarbetet varit att söka svar på frågan om hur offentliga fastighetsägare formulerar sina krav, jämförelse mellan anbud respektive uppdragsbeskrivning vad gäller LCC när de upphandlar projekterande konsulter. Undersökningen visade att det fanns ett antal upphandlingar där LCC-relaterade formuleringar fanns men omfattningen är begränsad och detaljerna kring varför och hur LCC-analyserna skulle göras är få. Det var också ett fåtal av de undersökta organisationerna som hade sådana formuleringar. Vidare visade undersökningen att krav på kompetens och arbetssätt kopplat till LCC helt saknades och att jämförelse mellan anbud endast i ett fall vägde in livscykelaspekter. Detta får till följd att anbudsgivarna saknar incitament att utveckla sina tjänster vad gäller LCC eftersom att det inte skulle ge dem några konkurrensfördelar när offentliga fastighetsägare genomför upphandlingar. Undersökningen visar dock på att en ambition fanns om att uppdragen skulle resultera i kostnadseffektiva och hållbara byggnader men det fanns i många fall ingen beskrivning om hur detta skulle uppnås. Slutsatsen som drogs av undersökningen är att den ekonomiska hållbarheten och den långsiktiga ekonomiska förutsägbarheten inte prioriterades högt men att det finns flera sätt som detta kan utvecklas på. Detta antingen genom att de offentliga fastighetsägarna bestämmer sig för när, varför och hur LCC-analyser ska genomföras under fastighetsprojektens tidiga skeden så att projekteringen kan styras av dessa analyser. Alternativt kan de implementera arbetssätt där de upphandlar fastighetsprojekt i ett tidigare skede och utvärdera vilket anbud som är de mest fördelaktiga genom att jämföra de olika förslagens LCC. Båda dessa förändringar skulle bidra till mer hållbara upphandlingar. / The running and maintenance costs of buildings often have a larger economic impact than the initial investment and Life-cycle costs (LCC) has been highlighted as a means of achieving sustainable procurement. Because of these circumstances it should be of interest to public property owners to adopt procedures where they can foresee the long-term economic impact of choices in the early stages of their projects by analyzing LCC. By analyzing the textual content of procurement documents, this degree project tried answering the question of how public property owners phrased their requirements, comparison between tenders and assignment conditions with regards to LCC when procuring design consultants. The survey showed that a number of the procurements had LCC related texts in the procurement documents but the extent of this was limited and the details about why and how the LCC analysis are supposed to be conducted were scarce. The number of organizations which had these texts where few. The survey also showed that there were no requirements regarding competence and procedures relating to LCC and that a comparison of tenders relating to life-cycle aspects only was applied in one procurement procedure. This leads to a lack of incentive for the tendering consultants to develop their services in regards to LCC because that would not give them any advantage in the competition for public property owner contracts. In contrast, there was an apparent ambition of designing cost effective and sustainable buildings in these contracts but there were in many of the cases no description of how this was to be achieved. The conclusion that was drawn from the survey was that the economic sustainability and the long-term economic predictability was not highly prioritized but there are a number of ways in which this can be developed. This can be achieved by the public property owners either by deciding when, why and how LCC analysis are to be conducted in the early stages of property projects so that the design is guided by these analysis. Another option is to implement early stage project procurement where the most advantageous tender is decided by comparing LCC. Both of these changes would contribute to more sustainable procurements.
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Sensitivity analysis and evolutionary optimization for building design

Wang, Mengchao January 2014 (has links)
In order to achieve global carbon reduction targets, buildings must be designed to be energy efficient. Building performance simulation methods, together with sensitivity analysis and evolutionary optimization methods, can be used to generate design solution and performance information that can be used in identifying energy and cost efficient design solutions. Sensitivity analysis is used to identify the design variables that have the greatest impacts on the design objectives and constraints. Multi-objective evolutionary optimization is used to find a Pareto set of design solutions that optimize the conflicting design objectives while satisfying the design constraints; building design being an inherently multi-objective process. For instance, there is commonly a desire to minimise both the building energy demand and capital cost while maintaining thermal comfort. Sensitivity analysis has previously been coupled with a model-based optimization in order to reduce the computational effort of running a robust optimization and in order to provide an insight into the solution sensitivities in the neighbourhood of each optimum solution. However, there has been little research conducted to explore the extent to which the solutions found from a building design optimization can be used for a global or local sensitivity analysis, or the extent to which the local sensitivities differ from the global sensitivities. It has also been common for the sensitivity analysis to be conducted using continuous variables, whereas building optimization problems are more typically formulated using a mixture of discretized-continuous variables (with physical meaning) and categorical variables (without physical meaning). This thesis investigates three main questions; the form of global sensitivity analysis most appropriate for use with problems having mixed discretised-continuous and categorical variables; the extent to which samples taken from an optimization run can be used in a global sensitivity analysis, the optimization process causing these solutions to be biased; and the extent to which global and local sensitivities are different. The experiments conducted in this research are based on the mid-floor of a commercial office building having 5 zones, and which is located in Birmingham, UK. The optimization and sensitivity analysis problems are formulated with 16 design variables, including orientation, heating and cooling setpoints, window-to-wall ratios, start and stop time, and construction types. The design objectives are the minimisation of both energy demand and capital cost, with solution infeasibility being a function of occupant thermal comfort. It is concluded that a robust global sensitivity analysis can be achieved using stepwise regression with the use of bidirectional elimination, rank transformation of the variables and BIC (Bayesian information criterion). It is concluded that, when the optimization is based on a genetic algorithm, that solutions taken from the start of the optimization process can be reliably used in a global sensitivity analysis, and therefore, there is no need to generate a separate set of random samples for use in the sensitivity analysis. The extent to which the convergence of the variables during the optimization can be used as a proxy for the variable sensitivities has also been investigated. It is concluded that it is not possible to identify the relative importance of variables through the optimization, even though the most important variable exhibited fast and stable convergence. Finally, it is concluded that differences exist in the variable rankings resulting from the global and local sensitivity methods, although the top-ranked solutions from each approach tend to be the same. It also concluded that the sensitivity of the objectives and constraints to all variables is obtainable through a local sensitivity analysis, but that a global sensitivity analysis is only likely to identify the most important variables. The repeatability of these conclusions has been investigated and confirmed by applying the methods to the example design problem with the building being located in four different climates (Birmingham, UK; San Francisco, US; and Chicago, US).

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