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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.
561

Simulation of photovoltaic airflow windows for indoor thermal and visual comfort and electricity generation

Haredy, Abdullah January 2016 (has links)
The alleviation of heating (in winter), cooling (in summer), artificial lighting and electricity use in office facilities is defined as a bioclimatic trend that offers sustainable building practice through a semi-transparent building integrated photovoltaic thermal envelope as a photovoltaic airflow window system. This thesis aims to produce synthesised design and strategies for the use of a proposed airflow window unit in office building in any given location and to maximise use of the renewable energy. Computational Fluid Dynamics (CFD), namely ANSYS Fluent 14.0, and ECOTECT have been employed to model the mechanical and natural ventilation of an office building integrated with a semi-transparent photovoltaic airflow window and the daylighting impact of various PV transparent degrees (15, 20, 25, 30 and 35 per cent) on the interior space, respectively, for winter and summer conditions. The use of such software has urged to establish a validation analysis a priori in order to ascertain the applicability of the tools to the targeted examination. The validation process involved a comparison of the results of CFD turbulence models, first, against benchmark and, second, against results of literature for identical component. The results of ECOTECT, in terms of daylight factor and illuminance level, were also compared against the results of Daysim/radiance, Troplux and BC/LC found in the literature. Excellent agreement was attained from the comparison of the results with errors less than 10 per cent. The study presents results of modelling of the airflow window system integrated into an office room for energy efficiency and adequate level of thermal and visual comfort. Results have revealed that the combination of mechanical and buoyancy induced flow spreads the heat internally warming the space to be thermally acceptable during the heating season whilst the mechanical convection is a main force for the cooling season. The thermal and visual comfort was compared for different PV airflow window transparent levels to determine the optimum PV transparency for the office space. Moreover, time-dependant and steady state conditions were imposed to predict the thermal and air behaviour for more elaborate investigation. The transient analysis was carried out, in sequential and individual base, according to the solar irradiance of each minute of working period, 8am-4pm (winter) and 5am-7pm (summer). The results obtained from transient and steady state, for both seasons, were compared and revealed negligible impact of transient effect. The PV electricity output was calculated from each transparency level under each condition, summer and winter (transient and steady). The predicted flow patterns, temperature distribution and the daylight factors in the room have been used to determine the most appropriate opening locations, sizes and system specifications for maintaining a comfortable indoor environment. The simulation investigation show that, for the proposed window model, optimum thermal and visual performance can be achieved from the PV transparency level of 20 per cent, during the heating season, and from the PV transmittance of 15 per cent, during the cooling season, where the PV output is highest. However the PV transparencies of 25, 30 and 35% can be reliable under altered conditions of operation.
562

The behaviour of unsaturated compacted naturally occuring gravel

Toll, D. G. January 1988 (has links)
No description available.
563

The mechanism of infection and decay of window joinery

Carey, Janice K. January 1980 (has links)
No description available.
564

Design of multiple tuned mass dampers for mitigation of wind induced vibrations

Chinien, Lomadeven Viken January 2000 (has links)
No description available.
565

Wood versus substitute materials in residential construction

Neilson, Ronald William January 1971 (has links)
Residential construction has been a focus of attention in North America in recent years. Rising construction costs, and growing social pressures to meet housing needs have resulted in a concentrated effort by government and industry to develop new and improved building methods. Wood frame construction techniques, although traditional in Canada, are not guaranteed a dominant position in the future. With the high volume of wood products consumed in residential construction, the forest industries have a large stake in this market. Two aspects of declining wood use in housing have been investigated in this thesis: (1) changing methods of construction; and (2) substitution of non-wood building materials for wood. Although recent projections indicate a strong housing demand to 1980, the types of dwellings constructed are equally important, single-family units consuming the greatest volume of wood products, and high-rise apartments the least. A strong trend toward apartment construction has been evident since 1950, fostered by rapid urban population growth, mortgage investment preferences, the high cost of urban land, and the lower cost of rental accommodation. It is estimated that the loss of wood products markets from 1960 to 1969 due to this trend was 1,355 million bd. ft. of lumber, 245,075,000 sq. ft. of plywood and veneer, and 151,068,000 sq. ft. of building board. Functional suitability is probably the most important determinant of materials choice. Tradition, a factor which has favoured wood frame building, is losing its influence. Availability of materials and vertical integration are not significant factors in Canada. Upward trends in the price of wood products, price instability, and the much higher research and development expenditures in competing industries can be expected to result in an accelerated rate of substitution of other materials for wood. Although wood performs well in many applications, its combustibility has been a great disadvantage for construction uses. Building codes have significantly limited its use, but have also hindered the introduction of new building techniques, and products made of substitute materials. Products made of aluminum, plastics, steel, and non-metallic minerals have had varying degrees of success in the housing market. Numerous developments such as aluminum and steel structural systems, plastic and metal sandwich panels, and precast concrete building systems, offer potential competition to wood frame methods. Vertical integration with the building industry, and more active promotion of, and technical assistance in wood frame methods may help curb the trend to apartment construction. Greater efforts to reduce costs, higher research and development expenditures, increased activity in market research, and greater efforts to reduce price fluctuations are necessary to prevent higher rates of substitution. More effort should be concentrated on the development of foreign markets, both to help reduce price fluctuations, and to provide alternate markets for those lost through substitution. / Forestry, Faculty of / Graduate
566

Frakt-och paketritning för KL-trä i Tekla / Freight and pakage drawing for CLT in Tekla structures

Andersson, Pär January 2017 (has links)
The purpose of this project has been to set up a freight drawing with accompanying packages drawing for CLT-wood in the program Tekla. This is based on the requirements for freight according to the Transport Agency and what applies to handling of the CLT boards regarding the working environment hazards. Based on the problems and requests from Martinsons, this project resulted in a freight drawing with accompanying package drawing. The package drawing is going to be a helpful tool for the project manager in the manufacture of the CLT boards. The freight drawing is going to provide comprehensive information about how to load the packages on the loading platform. The project is based on a reference model called Tallbocken, which is the model that Martinsons have used before. The model is basically a building, four floors tall, made almost entirely of CLT wood. An instruction has been made, based on this model, for the establishment of freight- and package drawing. A study has been made to ensure the demands from the Transport Agency regarding the shipping of compound elements. By visiting the production line in Bygdsiljum it was clear that the staff wanted a change in how to handle the CLT boards. Information about how to handle this was also an important message on meetings with the project manager and the production staff at the fabric in Bygdsiljum. To make sure that the drawings keep in line with the recommendations, there is an explanation for the review of building documents 90’s. This working project has resulted in an instruction for how to manage the establishing of freight- and package drawing. The instruction is attached as a supplement to this essay. This instruction explains the procedure step by step for how to create a freight drawing for CLT wood in Tekla structures by using a complete project template. / Syftet med detta projekt har varit att få en mer klar bild över vad som gäller, och hur man från en färdig projektmodell kan ta fram en frakt- samt paketritning för KL-trä i Tekla. Detta utifrån de krav transportstyrelsen ställer vid frakt, samt vad som gäller vid hanteringen av skivorna med avseende på arbetsmiljörisker. Utifrån de problem och önskemål personalen på Martinsons ser, har en fraktritning med tillhörande paketritning tagits fram. Paketritningen är tänkt att fungera som underlag för produktionsledaren vid tillverkningen av skivorna. Fraktritningen ska ge en större blick över hur dessa paket sedan ska lastas på flaket. Projektet har utgått från en referensmodell kallad Tallbocken som Martinsons tidigare arbetat med. Modellen är en fyra våningar hög byggnad till största delen gjord av KL-trä. Utifrån denna har en instruktion för upprättandet av frakt- samt paketritning tagits fram. För att transportstyrelsens krav vid frakt av sammansatta element ska säkerställas har en studie över detta gjorts. Det har även via besök vid produktionslinjen i Bygdsiljum framkommit de problem personalen ser vid hanteringen av KL-skivorna. Utöver detta har information om hanteringen framkommit genom medverkande på möten med projektledare samt produktionspersonal vid fabriken i Bygdsiljum. För att ritningarna i slutändan ska hålla sig till de rekommendationer som finns framtagna har en genomgång av bygghandlingar 90:s krav förklarats. Arbetet resulterade i en instruktion för hur upprättandet av en frakt- och paketritning kan genomföras. Instruktionen bifogas som bilaga i rapportens slut. Denna förklarar steg för steg tillvägagångssättet, att från en färdig projektmodell skapa en fraktritning för KL-trä i Tekla
567

Full Scale tests and Structural Evaluation of Soil Steel Flexible Culverts with low Height of Cover

Pettersson, Lars G. January 2007 (has links)
No description available.
568

Intelligent intervention : toward a definition for the process of design in the architecture of design/build

Poorzand, Mahmoud 11 1900 (has links)
The method of Design/Build is known for its practicality and skillful designers and builders. However, high quality buildings produced by this method suggest there is an intellectual wealth hidden beneath this technical practicality. To uncover this wealth, a definition for the processes of design used in this method must be constructed to clarify its intellectual aspects. Such a definition begins with the assumption that design is an intelligent process through which people arrange their environment. To uphold the intelligence of design, the interaction between human (designer, tradesperson, client, or inhabitants) and architecture must be maintained throughout the process. The unique conditions in the method of Design/build allow the human intellect to freely interpret and intervene in the processes of architecture. To fully exploit these conditions, a designer must develop a particular view, seeing architecture as combined processes rather than as an end-result. Via this view, it becomes evident that the arrangement of lines, forms, and structures of buildings is just a material manifestation of a deeper reality, i.e. the agreed values that an individual or society holds. These values are translated into two groups of design principles in architecture. The first group is geometrical and includes proportion, symmetry, order, and unity. The second group is relational and leads to consideration of adaptability, nature, need, tradition, and material. These principles define the relationships of architecture, humans, and the environment, expressing the role of intelligence in man-made settings. In Design/Build, these principles can be incorporated into the processes of design far more than in any other method, because architecture is intimately connected to environment (social and natural), and there is a dynamic interaction between designing and building. This method sees architecture as a combination of processes, considering design not as rules and regulations, but as a process that is empowered and motivated by the events of everyday life. This method arrives at the rules and regulation of architecture only after recognizing this fact. Without the attendance of life in an architectural process, the geometrical and relational principles of design are dull and meaningless. By establishing this view, this paper hopes to construct a definition for the design process of Design/Build, a definition that does not deal solely with the technicality and practicality of this method but rather with the intellectual aspects of the process. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate
569

Still Creek interpretation facility

Boothroyd, Gregory Stephen 05 1900 (has links)
This thesis explores the notion of site as a generative basis for architecture. Site is conceived not only as a plot of land where a building is located, but also as something that is the result of agency: the architectural intervention. Site is thus constructed with architecture; it is as much a consequence as a thing. Still Creek was chosen as a provocative site in which to explore this idea. Once Vancouver's largest salmon-bearing stream. Still Creek now exists in a barren, degraded state — the result of a century of urbanization. In its fragmented course from its headwaters to Burnaby Lake, Still Creek flows above and below ground through a diversity of site conditions, ranging from a primeval ravine to a polluted industrial area. Recently, sensibilities about the stream have changed. There are presently a variety of groups interested in Still Creek, not only as a public amenity, but also as an urban ecosystem. In response, it was proposed that (1) an urban trail be located along the discontinuous course of the stream, and (2) a facility be located along the stream that addresses some of the needs of these interested groups. The Still Creek Interpretive Facility marks both the beginning of the stream and the start of the urban trail. Located at the edge of the Renfrew Ravine where the stream first emerges from a subterranean culvert, the building makes apparent the many forces present on the site. An initial gesture of excavation reveals the culvert and demarcates a constructed and a natural edge. The constructed edge of the excavation is heightened with a veil of translucent solar panels that diffuse sunlight and help power the building. A wood screen along the natural edge of the excavation acts as a foil to the alder forest, allowing the building to maintain a quiet presence in the ravine as well as creating shimmering views of colour and light. The stream fills the lowest part of the excavation, mitigating high runoff flows and making a reflective pool for light, precipitation, and sound. The excavation and screen walls form a vessel into which mute volumes are inserted, creating a variety of indoor and outdoor spaces, some relating more to site, others relating more to programme. Exterior building circulation winds through the whole assembly — an extension of the urban trail — forming a rich experiential descent from street...through building...to stream beyond... / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate
570

Arctic/subarctic urban housing : responses to the northern climates

Ross, John Frederick January 1977 (has links)
This study investigates the effects of the arctic and subarctic climatic conditions on the built environment, urban housing in particular. The method of research and development of this thesis has been through a literature search coupled with my own working/ design experience in the North (Fairbanks, Alaska) for three years. The thesis is in three parts (chapters 2, 3» and k)» The first part makes a comparison of the climatic conditions in the different northern climatic zones within the state of Alaska, as well as comparing these to more southern climatic zones. The second part (main body of the thesis) investigates the building design responses (solutions) to the varied climatic conditions: solar radiation, temperature, precipitation, wind, and special climatic conditions (humidity/moisture potential, blowing snow, permafrost, and frost heave). This analysis is organized into "planning levels". Four planning levels are established which deal with ^) site layout/circulation patterns, (2) building size, shape, and orientation, activity/space arrangement, and (J) detailing of the building fabric. Using the parameters established in part 2, planning level 1, part 3 illustrates a townsite layout for a specific site, the Willow Site in subarctic Alaska where the new Alaska State Capital i6 to be located. The majority of people who live in the northern urban areas look to the south for their housing styles and designs as well as assess housing quality by "southern standards". Presently there are few ways for people living ln the North to evaluate the quality of housing for that particular climate except through trial and quite often error. This thesis produces an ordered listing of building/housing responses to the northern climates which can be disseminated to the public who can then better assess housing performance and quality for their particular physical environment. The information contained within this thesis would also be of use to professionals in arriving at design decisions for housing/building in northern areas. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate

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