Tesis sobre el tema "Window shades"

Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 16, 2010). Includes bibliographical references. Also issued in print.

Recombination line profile shapes are derived for ionized spherical stellar winds at radio wavelengths. It is assumed that the wind is optically thick owing to free-free opacity. Emission lines of arbitrary optical depth are obtained assuming that the free-free photosphere forms in the outer, constant expansion portion of the wind. Previous works have derived analytic results for isothermal winds when the line and continuum source functions are equal. Here, semi-analytic results are derived for unequal source functions to reveal that line shapes can be asymmetric about line center. A parameter study is presented and applications discussed.

Windows provide building occupants with important physiological and psychological benefits but are absent from many indoor spaces. It is argued that most existing attempts at compensating for an absence of windows fall short because they lack either outdoor environmental information or sensory stimulation. A wind-animated digital-tree shadow was used to test this hypothesis. The work concludes that the following strategies are likely to help most to compensate for an absence of windows: (1) establishing a live connection with the outdoors; (2) introducing controllable sensory variation into a space; (3) making such change a source of natural environmental information. It is suggested that these approaches could be helpful used either separately or in combinations but that a live connection with the outdoors that introduces controllable naturally-generated change into a space would likely be most effective. The video files that accompany this thesis show the digital shadow with wind and computer generated movement.

Design is about understanding a space. It is about integration of light and air in building design. It is about light, shadow, reflection. It is about wind, its movement and escape. Through designing this project I was able to explore how sun, wind and light can be used effectively in a building design, in my project, in an office environment. The fire, the Light; the energy is the inspiration behind the origin of Architecture. Energy brings architecture into the world of processes and life and Architecture brings together Fire and Shelter, Chaos and Organization. Day lighting or the use of natural light in a building is one of the fundamental elements used to bring an essential experience of visual comfort and outside world environmental stimulation for all building occupants. The History of Architecture, said Le Corbusier, is a history of the struggle for light, the struggle for the window. This thesis assembles the research, conceptualization and final development of the office building design with an integration of light and wind.
Master of Architecture

Magistro darbe nagrinėjamas mokomasis aerodinaminis vamzdis, su kuriuo bus galima atlikti laboratorinius darbus ir nesudėtingus mokslinius tyrimus. Aptariama aerodinaminio vamzdžio reikšmė studentams, Lietuvos ūkiui ir aplinkosaugai. Taip pat pateikiama, kokius bandymus su aerodinaminiu vamzdžiu bus galima atlikti Pastatų energetikos katedroje. Apžvelgti laboratorijos įrangos gamintojų – Aerolab, G.u.n.t, Armfield, Stirolab, GDJ Inc mokomieji aerodinaminiai vamzdžiai, projektavimo rekomendacijos. Pastatų energetikos katedrai suprojektuotas aerodinaminis vamzdis, papildomai pridėti triukšmo slopintuvai prieš ir už ventiliatoriaus. Taip pat atlikta kompiuterinių programų, kuriomis naudojantis galima atlikti oro srautų moduliaciją, analizė, ir pasirinkus tinkamiausią programą atlikta Pastatų energetikos katedros aerodinaminio vamzdžio darbinės kameros moduliacija. Šio baigiamojo darbo rezultatas – pagamintas ir surinktas mokomasis aerodinaminis vamzdis, kuris bus naudojamas laboratoriniams darbams ir tyrimams atlikti. Darbą sudaro 11 dalys: įvadas, 11 skyrių dėstomoji dalis, išvados, literatūros sąrašas. Darbo apimtis – 65 p. teksto be priedų, 39 iliustr., 9 lent., 30 bibliografiniai šaltiniai. Atskirai pridedami darbo grafikai ir priedai.
Masters‘ thesis deals with an educational wind tunnel which is to be used to carry out laboratory works and simple research. It disscuses the importance of wind tunnel for students, Lithuanian economy and environment protection. It also presented tests those can be made with wind tunnel in the department of buildings’ energetics. The educational wind tunnels, design recommendations of the laboratory equipment manufacturer – Aerolab, G.u.n.t, Armfield, Stirolab, GDJ Inc were overviewed. Wind tunnel for department of buildings’ energetics was designed, in addition silencers before and behind the fan were added. There are also made an analysis of computer programs, which enable air flow modulation, and selecting the best program the wind tunnel working chamber modulation of the department of buildings’ energetics was performed. The result of the thesis – produced and assembled educational wind tunnel, which will be used for laboratory work and research. The work consists of eleven parts: introduction, describtion, conclusions, references. Work size – 65 pages without appendixes, 39 figures, 9 tables, 30 references. Appendixes.

A supersonic wind tunnel, with a 20" x 20'" test section cross sectional area, was designed and constructed at the Techsburg Wind Tunnel Facility in order to determine the lift and drag on irregularly shaped fragments in supersonic flow. Prior to beginning the wind tunnel design process, a blowdown analysis model was created in order to determine the influence of a number of parameters on tunnel run time and test gas properties throughout the tunnel circuit. The design of the settling chamber, test section, supersonic nozzles, diffuser, and exhaust are presented in this thesis. Diffuser performance has a large influence on wind tunnel efficiency and run time. Therefore, significant efforts should be taken in order to attain the highest possible pressure recovery within the diffuser. The design of wind tunnel components, as well as their stress analysis, was conducted using SolidWorks. The control valve and silencer were sized and selected for the expected tunnel operating conditions. Since the control valve tends to encompass a significant portion of the overall tunnel cost, care must be taken to ensure it has a large enough flow capacity to produce the desired test conditions. Also, attempts must be made to accurately predict the total pressure loss through the silencer, since this loss can have a large impact on the total pressure ratio necessary to produce the design Mach number. Upon completion of the design process, the supersonic wind tunnel was assembled, and shakedown testing was conducted. During shakedown testing it was determined that the wind tunnel was capable of producing Mach 2 flow in the test section. Following shakedown testing, a flow survey was conducted in order to ensure uniform Mach number flow exists throughout the region occupied by the fragments. Based on the flow survey it was determined that within the middle 60% of the test section, the average Mach number was 1.950 and varied by only 0.56% within this region. Two irregularly shaped fragments were tested at Mach 2 flow, over an effective 360° pitch sweep, with wind tunnel runs performed every 10 degrees. Based on the measured force data for both fragments, the lift appeared to follow a sinusoidal curve, with minimum values at 0, 90, and 180° balance pitch angle, and maximum values occurring around 45 and 135° pitch angle. The drag force was observed to follow a gradual curve with minimum values at 0 and 180° balance pitch angle, as expected since the fragment presented area is generally least in this orientation. The maximum drag was found to occur at a balance pitch angle of 90°, once again as expected since the fragment presented area is generally greatest at this angle. It was also observed that the fragment drag tended to be greater for a fragment orientation which places the concave side of the fragment into the direction of the flow.
Master of Science

The supply of energy is a key factor in modern societies. As the old fossil sources for energy are dwindling, conflicts arise between competing nations and regions. Fossil energy sources also contribute to the pollution of the environment and emission of greenhouse gases. With renewable energy sources many of these drawbacks with fossil fuels can be eliminated as the energy will be readily available for all without cost or environmental impact. Combining the renewable energy sources will be very effective, particularly in commercial areas where lake of electricity is high. The cost of combining onshore wind and solar power plant is affordable. Furthermore there is no power failure or load shedding situation at any times. When it is manufactured in a large scale, cost of this integrated natural resources power generation system is affordable. Moreover there is no power failure or load shedding situation at any times. Therefore, it is the most reliable renewable power or electricity resources with less spending and highly effective production. ref [1]. The thesis work would take planning of offshore renewable plant (Lillgrund) with considering the resources of renewable power. The study would take in account combining the Lillgrund wind farm with solar system and take close look into the advantage and disadvantage of combining the renewable resources together and figure out if such station can work in proper way and provide sufficient power production. The study would take in account the effect of each resource on other resource, also calculations would be done. The study site is Lillgrund in south of Sweden. The Lillgrund wind farm is the most important offshore wind power plant installed in Sweden with a total capacity of 110 MW, corresponding to 48 turbines. ref [2].

Off-grid hybrid renewable energy systems are known as an attractive and sustainable solution for supplying clean electricity to autonomous consumers. Typically, this applies to the communities that are located in remote or islanded areas where it is not cost-effective to extend the grid facilities to these regions. In addition, the use of diesel generators for electricity supply in these remote locations are proven to be uneconomical due to the difficult terrain which translates into high fuel transportation costs. The use of renewable energy sources, coupling with the diesel generator allows for the diesel fuel to be offset. However, to date, a common design standard for the off-grid system has yet to be found and some challenges still exist while attempting to design a reliable system. These include the sizing of hybrid systems, coordination between the operation of dissimilar power generators and the fluctuating load demands, optimal utilisation of the renewable energy resources and identifying the underlying principles which reduce the reliability of the off-grid systems. In order to address these challenges, this research has first endeavoured into developing a sizing algorithm which particularly seeks the optimal size of the batteries and the diesel generator usage. The batteries and diesel generator function in filling the gap between the power generated from the renewable energy resources and the load demand. Thus, the load requirement is also an important factor in determining the cost-effectiveness of the overall system in the long run. A sensitivity analysis is carried out to provide a better understanding of the relationship between the assessed renewable energy resources, the load demand, the storage capacity and the diesel generator fuel usage. The thesis also presents the modelling, simulation and experimental work on the proposed hybrid wind-diesel-battery system. These are being implemented with a full-scale system and they are based on the off-the-shelf components. A novel algorithm to optimise the operation of a diesel generator is also proposed. The steady-state and dynamic analysis of the proposed system are presented, from both simulation and an experimental perspective. Three single-phase grid-forming inverters and a fixed speed wind turbine are used as a platform for case studies. The grid-forming inverters adopt droop control method which allows parallel operation of several grid-forming sources. Droop control-based inverters are known as independent and autonomous due to the elimination of intercommunication links among distributed converters. Moreover, the adopted fixed speed wind turbine employs a squirrel cage induction generator which is well known for its robustness, high reliability, simple operation and low maintenance. The results show a good correlation between the modelling, the experimental measurements, and the field tested results. The final stage of this research explores the effect of tower shadow on off-grid systems. Common tower designs for small wind turbine applications, which are the tubular and the lattice configurations, are considered in this work. They generate dissimilar tower shadow profiles due to the difference in structure. In this research, they are analytically modelled for a wind turbine which is being constructed as a downwind configuration. It is proven that tower shadow indeed brings negative consequence to the system, particularly its influence on battery lifetime within an off-grid system. This detrimental effect occurs when power generation closely matches the load demand. In this situation, small frequent charging and discharging cycles or the so called microcycles, take place. The battery lifetime reduction due to these microcycles has been quantified and it is proven that they are not negligible and should be taken into consideration while designing an off-grid hybrid system.

Nas últimas décadas, tem-se observado uma forte tendência de edificações cada vez mais altas, esbeltas e flexíveis, o que exigiu novas considerações no cálculo estrutural de edifícios, tornando a ação do vento um elemento de grande relevância nos projetos. Além disso, o denso agrupamento de edificações nos centros de grandes cidades adicionou uma variável para um fenômeno que já era complexo: devido à proximidade, um edifício passa a influenciar o campo aerodinâmico de outros, podendo provocar grandes alterações nas pressões, além de fenômenos dinâmicos difíceis de determinar por métodos analíticos. Instruções normativas, em geral, limitam-se a prédios altos com padrões arquitetônicos regulares, afastando-se da realidade dos projetos construídos na prática, que vêm exibindo geometrias cada vez mais complexas e não convencionais. Este cenário justifica a realização de extensos estudos dentro do tema em questão, a fim de que se obtenha uma melhor compreensão dos fenômenos dinâmicos envolvidos e uma orientação mais abrangente na etapa de pré-dimensionamento da estrutura. Neste contexto, a proposta desta pesquisa consiste em dois estudos de caso, de edifícios construídos no Brasil e ensaiados em túnel de vento, que possuem uma geometria similar (em formato de “V”), mas com dimensões e detalhes arquitetônicos distintos. O objetivo é o de promover uma caracterização aerodinâmica, avaliando os carregamentos atuando global e localmente, tanto para o modelo considerado isolado quanto incluindo as condições de vizinhança. Além das ações, estudou-se o espectro do vento que se aproxima, e determinou-se as funções de admitância aerodinâmica correspondentes. Em ambos os edifícios, verificou-se que a incidência do vento aproximadamente perpendicular a uma das abas corresponde a uma direção crítica em termos de efeitos dinâmicos: os espectros dos carregamentos globais se mostraram muito similares, apresentando picos pronunciados que indicam a possibilidade de desprendimento cadenciado de vórtices; as funções de admitância aerodinâmica também evidenciaram um formato muito semelhante. O estudo em questão oferece um meio de validação para estudos futuros que utilizem modelos de ensaio simplificados, além de servir de referência para uma possível revisão da norma brasileira NBR 6123/1988 – Forças devidas ao vento em edificações, contribuindo com os avanços do conhecimento relativo a efeitos dinâmicos do vento em edifícios altos e irregulares.
In the last decades we observed a strong trend in constructing buildings increasingly tall, slender and flexible, which has asked for new consideration in the structural calculus of buildings, making the wind a relevant element in the design procedures. The grouping of buildings downtown in big cities has added another variable to an already complex phenomenon: due to the proximity, a building influences in the aerodynamic field of others, leading to pressure modifications and dynamic effects hard to determine by analytical methods. Instruction codes, in general, are limited to regular tall buildings, in contrast to the reality of projects built in practice, which have been exhibiting architectonic patterns increasingly complex and unconventional. This scenario justifies extensive studies among aerodynamic of irregular tall buildings, with the purpose of acquiring a better comprehension regarding the dynamic phenomena involved and a more accurate direction on the pre-design phase. In this context, the proposal of this research consists of two case studies about buildings constructed in Brazil and tested in wind tunnel, which have a similar geometry (V-shaped) but different dimensions and architectonic details. The objective is to promote a complete aerodynamic characterization, assessing the loads acting as a whole and also locally, with both isolated and interference conditions. Besides the action, the velocity spectrum of the approaching wind and the corresponding aerodynamic admittance were studied. Either case, it was verified that the wind incidence nearly perpendicular to one of the frontal facades is a critical direction from the perspective of dynamic effects: the spectra of global loads were very similar, with a peak emerging on the graphs, which indicate the possibility of vortex shedding; the admittance function also showed a very close format. This study offers an instrument of validation for future researches that use simplified test models, besides to fit as a reference to a possible revision of the Brazilian code NBR 6123/1988 – Wind load on building structures, contributing to the knowledge advances regarding dynamic effects on irregular tall buildings.

This thesis contributes to the growing body of scholarship surrounding historical and filmic representations of the past. Moreover, it seeks to further the understanding and practical use of this sub-field in history by examining two films: Amistad (1997); and, The Wind That Shakes the Barley (2006). Building on the insistence of scholars such as Robert Rosenstone and Hayden White, this thesis seeks to evaluate historical films on their own terms as representations of the past that must be judged according to their own conventions. Cinema's attraction to historical subjects is not a recent phenomenon. However, the past two decades, have seen a marked increase in the academic critique of 'historical films' - most notably Hollywood features and television documentaries. Moreover, the appetite of the general public for filmic treatment of historical topics continues unabated. While it is agreed that historical film cannot be judged according to the criteria used in accessing traditional modes of historical representation, there is little agreement about what criteria, precisely, should be used in evaluating historical films' historical attributes and implications. This thesis commences with a general theoretical and methodological survey of the literature in this relatively new sub-field. It then analyses the film Amistad and its reception and criticism amongst historical professionals. This analysis, coupled with the findings of the first chapter, forms the basis for an original and independent review of The Wind That Shakes the Barley, a film that has not yet been widely critiqued by historians. The thesis suggests how historical films may be fruitfully evaluated in ways that are sympathetic both to the peculiar exigencies of the medium and the traditional concerns of historical scholarship.

L'objet de ce travail est l'elaboration de programmes pour micro-ordinateurs ibm-pc et compatibles, permettant le calcul des apports solaires par les ouvertures de batiments, dans le cas d'une architecture non conventionnelle et d'un environnement complexe. Les apports par rayonnement direct sont calcules par le programme insol-b qui peut aussi servir a la determination des ombres portees. Les apports par les rayonnements reflechis et diffus sont determines par le programme insol-dr; le modele de ciel anisotrope de perez est utilise pour le rayonnement diffus

A presente tese investiga a sombraenquanto elemento essencial para a definição do espaçoe do tempona arquitetura. A presença da sombra na arquitetura e na arte é estudada através de conceitos da filosofia e da antropologia. Escuridão não significa necessariamente que um lugar não seja visível, torna-se apenas menos visível. Pela sua própria natureza, a sombra atribui um certo grau de indefinição ao espaço. Devido à perceção e visão humanas, a sombra sugere também um grau de intimidade em relação ao espaço iluminado, o que reforça a definição do espaço em si, e da sua experiência sensível. Aqui, mesmo uma arquitetura sem paredes ou portas pode definir diferentes espaços devido à presença da sombra. Este estudo teórico complementa e antecipa as intenções do projeto para uma casa nas colinas de Roncão, no Alentejo. O projeto consiste num muro que estabelece um momentode tensão em relação à paisagem e cria um percurso, que em seguida dá origem a um espaço habitado. A casa é composta por uma parede, uma janela e cinco espaços. A presença de uma única abertura circular, que varia a posição daluz do sol ao longo do dia, enfatiza a importânciada sombra. Ela tornase no elemento essencial que define os espaços e sugere o melhor momento para os utilizar. Desta forma, a sombra é capaz de definir os dois temas que compõem a arquitetura: espaço e tempo.
The following thesis investigates the shadow as an element defining spaceand timein architecture. The shadow is studied, in art and architecture through concepts of philosophy and anthropology. Darkness does not necessarilymean that a place is not visible but just less visible. By its very nature shadow gives a lack of definition to space. Furthermore, because of human perception and vision, the shadow creates a degree of intimacy compared to the illuminated space. This reinforces the definition of the space itself and its sensory experience. Here, even architecture without walls or doors can be defined in different spaces, thanks to the shadow. This theoretical study complements and anticipates the project of a house on the hills of Roncão, in Alentejo. The project is composed of a wall which, concerning the landscape,creates a space of tension where a path is definedfirst, and then the inhabited space. The house consists of a wall, a window and five areas. The presence of a single circular opening, which varies the position of sunlight throughout the day,emphasizes the darkness in the house. The shadow is the fundamental element suggesting the most comfortable place and the moment in which to use it. The shadow, therefore, is capable of defining the two themes that compose architecture: space and time.

碩士
國立臺灣藝術大學
工藝設計學系
103
Niello is an old metalworking technique with a fascinating dark blue. Its origins can be traced back to the ancient Egyptian dynasty and then gradually spread in Europe and Asia. Niello technology was prevalent through the history; however, there has been few relevant research on it in Taiwan. The collection of the artworks investigates the best method of making Niello by exploring some literature of Niello with a series of studying on Niello alloy, formulation research, and melting production experimental approaches. Lin Family Garden was built in 1853, which was one of the private gardens of the richest families in Taiwan. It is the only one place existing today, which has integrity of landscape architecture. The garden is full of ingenuity and wisdom of Chinese’s landscape architecture. The artworks created in this study show combine Niello techniques with penetrating windows grilles as to extend Lin Family Garden tradition. Therefore, it helps to create the metal craft and prints with the characteristics of the Lin Family Garden Penetrating Windows.

碩士
國立東華大學
藝術創意產業學系
103
This thesis is mainly focused on “windows,” analyzing and researching the works of photographic creations and related window views. Through gazing at all kinds of windows, I hope to present the combinations of inner feelings and emotions that windows are equipped with. First, I would like to look back on some window-oriented photographic works and then analyze each case. What’s more, I also attempt to interpret the life image, the flow of the light and shade, and the emotional connections on the works of the window frame scenes that some photographers have displayed. The above are all the references for my creation and research. We can see windows everywhere in the city, and they are just like the eyes of the buildings. Eyes are described as the window of the soul. By observing inside and outside of the window views, we get to know they are rich in emotional combinations, changes of light and shade, interaction among people, the composition of frame scenery, etc. When we gaze at window frames, it is like appreciating the paintings in a quiet gallery. Also, we seem to watch a vivid and imaginary movie or play coming directly out of the frames. They are all working as the functions of the screens. When reviewing the works of window scenes, I can conduct an analysis of the image of why windows exist in our life. Only by watching the visual effects of the frames, noticing the distance and barrier that frames show and extending to the peek between seeing and gazing can I have a general idea of what the image is really all about. Window frames are the main media that I use in my personal creation. They include the scenes of stores, lives, and vehicles. Standing and gazing in front of different windows, the person who peers and the person who is peered can have their own special visual feelings. And by looking closely at the different scenes, I can present how people feel and what they mean to them.

碩士
樹德科技大學
建築與環境設計研究所
98
The main purpose of this paper is to set up a efficient model for housing window shade saving energy – by reference, compiling mathematical formula, and computer calculate ability. Researching (1) Solar radiation theory (including the elevation angle and azimuth of the sun theories, geographical longitude and latitude and sunshine rate and meteorological data, the solar constant and solar radiation energy such as solar radiation). (2) Principles of Building Sunshine (windows horizontal, vertical, grid-style shading types). (3) The theory of shading shelter calculation (analytic geometry of space of shading, coordinate calculation area method, hourly direct solar radiation = hourly vertical solar radiation *window area). Related to expected results are as follows: 1 .Solar radiation database. 2. Accumulated shading solar radiation database. 3. Database of window shade types. 4. The economic benefits of different shade type. This study writes a set of program to calculate the window shade solar energy, to be used in theory and practice. By this program could easily save 50~60% electric energy.

With the advances in construction methods, materials, and technologies, more high rise buildings with unconventional shapes have been continuously built. A large number of tall buildings with irregular shapes have been built in past years in urban areas due to a shortage of land and demand for good architectural design. As the wind velocity increase with height, the top of the building may experience a higher wind. Tall buildings are the structures that are more sensitive to wind loads, and thus the response to the wind load is the main concern of designers while designing tall buildings. Most of the tall buildings are bluff bodies. As flow separates and reattaches around bluff bodies, the external shape of tall buildings plays an influential role in the generation of wind load on high-rise buildings. High-rise residential buildings are commonly built as twin towers. Twin tall buildings are subjected to the proximity effects due to small gaps between them. Under the influence of proximity, the wind load on tall buildings may differ from that on the isolated buildings. The codes and standards related to the wind loads are generally do not consider these proximity effects. Further, no analytical formula is available to evaluate the wind effect on irregular shape tall buildings and proximity effects between twin towers, which necessitates more experimental or analytical study for irregular shape tall buildings. In the present study, four different plan shapes, namely square, plus-1, plus-2, and H plan, are considered. The floor area and height of all four models are kept the same. The plus-1 and plus-2 plan shapes are prepared by providing the large-sized recessed corners in the rectangular plans of different sizes, whereas the H-plan shape is prepared by providing recessed cavities on the two opposite faces of a rectangular plan shape. The study has been conducted in three phases, namely (i) pressure measurements through wind tunnel study in isolated and interference conditions, (ii) force evaluation through pressure integration technique, and (iii) study of the response of prototype buildings to wind loads calculated on scaled models. In the first phase, to investigate the wind-induced pressure at the surfaces of the building, four rigid models scaled at 1:300 as described earlier are tested in an open circuit layer viii wind tunnel having a working section of 2 m x 2 m cross-section and 15m length. The wind flow characteristics inside the tunnel are simulated similar to the Indian sub-urban terrain with well-scattered objects with a height between 1.5 to 10 m according to the Indian standard IS 875 (part 3): 2015. The mean wind speed and turbulence intensity profile with a power-law index of 0.22 is simulated in the tunnel. The turbulence intensity near the floor of the wind tunnel and wind velocity at building height is 12% and 9.87 m/sec, respectively. The pressure models are prepared with a 4 mm thick transparent Perspex sheet with stiff faces to ensure sufficient rigidity and strength of the model. The pressure measurement study is conducted in two parts. In the first part, the pressure models are tested in isolated conditions for wind directions of 0, 300 , 600 , and 900 angles at an interval of 300 to assess the effects of wind direction on the surface wind pressure. In the second part, the pressure models are tested with an interfering building model present upstream of the pressure model at different locations. The interfering building models are made of wooden material with dimensions similar to the pressure models. Interference effects are assessed for three different positions of interfering building, such as full blockage, half blockage, and no blockage. From the time history of fluctuating pressure data, the mean, maximum, minimum and r.m.s pressure coefficients are evaluated at each pressure point on the surface of the model in isolated and interference conditions. In the second phase of the study, local wind force coefficients at various levels of the models and the overall base forces have been evaluated through the pressure integration technique. The local forces at each level of the model are calculated by integrating the local forces of each pressure tap at that particular level. The overall base forces and moments are calculated by integrating the force and moment of all levels. The forces in along-wind and across wind directions are presented as mean and r.m.s coefficients. In the third phase of the study, the responses of prototype buildings of the four models to the wind load calculated through wind tunnel study on the scaled models are studied through analytical study. The effects of various wind directions and various interference conditions have been assessed on the response of four buildings through stress parameters, including axial forces, the moment in X and Y directions, and twisting moments. At last, ix the effects of the various plan shapes on the response of tall buildings under wind loads have been investigated. The results show that wind flow direction has significant effects on the pressure distribution on the surfaces of the models. For the square model, the wind directions normal to the surfaces are critical direction. The wind direction of 600 generates the most critical positive and negative mean pressure on the plus-1 model. The effects of wind direction on the pressure on the plus-2 model are not as much severe as the plus-1 model. Pressure distribution on the front faces of all models is completely different in interference conditions from those in isolated conditions. The influence of interference on the square and H-plan model are beneficial, while it has negative effects on some face of the plus-1 model. The along-wind mean local wind forces at normal wind incidence are higher than those at oblique wind incidence. The along-wind forces in all interference conditions decreased significantly from those in isolated condition. The values of along-wind forces: drag and moment at normal wind incidence of 00 and 900 angles are larger than those at oblique wind incidence in isolated condition. The CFD and CMD values are likely to be reduced significantly in interference conditions. The effects of change in cross-sectional shape are significant on the across-wind forces. The effects of cross-sectional shape are dominant for wind flow at oblique angles in isolated condition while more at half blockage condition of interference. The axial force is independent of the building cross-section. All the buildings have the same axial force in central columns. The maximum twisting moment is observed in PL-2 Building in isolated as well as in interference conditions. The H building show the best performance in isolated condition.

This thesis analyzes the feasibility of having an integrated wind and solar farm to optimize the use of land resources and capital investment by evaluating the effect that wind turbine shadows have on the area surrounding them. Two methods are used to predict shadow impact. The first method is based on the traditional textbook “Clear Sky” equations, which have maximum sensitivity to shadows because the method considers every day to be a perfect day. The second method uses measured global-horizontal and diffuse-horizontal solar radiation in units of W/m2, which take into account the true variations of daily conditions. The calculations are performed for 1 square meter surfaces, over different assumed areas of a wind power plant, for every second of the day. For purposes of shadow calculations, the tip-top height (i.e., tower height plus blade length) is used. All calculations are performed with the specifications of a GE 1.5 MW wind turbine, which is the most commonly used wind turbine in USA.
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The Wind Turbine industry continues to drive towards high market penetrationand profitability. In order to keep Wind Turbines in field for as long as possiblecomputational analysis tools are required. The open source tool QBlade[38] softwarewas extended to now contain routines to analyse the structural properties of WindTurbine blades. This was achieved using 2D integration methods and a Tapered Euler-Bernoulli beam element in order to find the mode shapes and 2D sectional properties.This was a key step towards integrating the National Renewable Energy LaboratoriesFAST package[32] which has the ability to analyse Aeroelastic Responses. The QFEMmodule performed well for the test cases including: hollow isotropic blade, rotatingbeam and tapered beam. Some improvements can be made to the torsion estimationof the 2D sections but this has no effect on the mode shapes required for the FASTsimulations.

In this work, two approaches for computing the near-field distribution around wind turbines are proposed, including: (1) Huygens Principle and (2) the parabolic equation technique. In order to simplify the problem, the cylinder model is utilized to represent the wind turbines and transform the problem into a two-dimensional case. To make Huygens Principle computationally tractable, several approximations are made based on the problem geometry especially modelling the cylinder as a plate. The expression of the electromagnetic field radiated by the equivalent magnetic current can be analytically solved by the error function. To verify the results, FEKO is utilized to simulate the scattering of infinitely long cylinders using periodic boundary condition (PBC). In order to solve the problem of multiple cylinders, a modified method is derived. For more accurate results, the parabolic equation (PE) technique is utilized to solve this problem, which is usually utilized to solve wave propagation problems. In this case, wide-angle approximation is used to solve the parabolic equation, which can obtain accurate results in a region of up to 45 degrees. Although these two approaches are not full-wave simulation, the calculation time is significantly reduced and the error is acceptable. To further verify the computed results by the parabolic equation technique, two commercial transceivers from Time Domain Corporation are used to measure the field distribution behind a finite-length metal pole. The frequency-domain results are obtained from the measured time-domain results using the fast Fourier transform. It is shown that the computed results by the parabolic equation technique agree well with the measurement results.
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In a growing number of information-processing applications, such as network-traffic monitoring, sensor networks, financial analysis, data mining for e-commerce, etc., data takes the form of continuous data streams rather than traditional stored databases/relational tuples. These applications have some common features like the need for real time analysis, huge volumes of data, and unpredictable and bursty arrivals of stream elements. In all of these applications, it is infeasible to process queries over data streams by loading the data into a traditional database management system (DBMS) or into main memory. Such an approach does not scale with high stream rates. As a consequence, systems that can manage streaming data have gained tremendous importance. The need to process a large number of continuous queries over bursty, high volume online data streams, potentially in real time, makes it imperative to design algorithms that should use limited resources. This dissertation focuses on processing exact results for join queries over high speed data streams using limited resources, and proposes several novel techniques for processing join queries incorporating secondary storages and non-dedicated computers. Existing approaches for stream joins either, (a) deal with memory limitations by shedding loads, and therefore can not produce exact or highly accurate results for the stream joins over data streams with time varying arrivals of stream tuples, or (b) suffer from large I/O-overheads due to random disk accesses. The proposed techniques exploit the high bandwidth of a disk subsystem by rendering the data access pattern largely sequential, eliminating small, random disk accesses. This dissertation proposes an I/O-efficient algorithm to process hybrid join queries, that join a fast, time varying or bursty data stream and a persistent disk relation. Such a hybrid join is the crux of a number of common transformations in an active data warehouse. Experimental results demonstrate that the proposed scheme reduces the response time in output results by exploiting spatio-temporal locality within the input stream, and minimizes disk overhead through disk-I/O amortization. The dissertation also proposes an algorithm to parallelize a stream join operator over a shared-nothing system. The proposed algorithm distributes the processing loads across a number of independent, non-dedicated nodes, based on a fixed or predefined communication pattern; dynamically maintains the degree of declustering in order to minimize communication and processing overheads; and presents mechanisms for reducing storage and communication overheads while scaling over a large number of nodes. We present experimental results showing the efficacy of the proposed algorithms.

Most scientific studies concerning energy conservation benefits of trees have been completed in cooling dominated climates or have involved model-based engineering studies. An infestation of the Asian Longhorned Beetle (ALB) (anoplophora glabripennis) has initiated an extensive tree removal program in Worcester, Massachusetts. A June 1, 2011 tornado in Springfield, Massachusetts has damaged a randomized sample of the urban canopy cover in Springfield. These events provide natural, controlled experiments to quantify the energy use impact of trees in real-world settings. Large-scale tree removal and natural disasters completely transform the landscape. Due to the reduction in shade, near-ground temperature increase is substantial. With the trees gone, the increased velocity of cold winter winds is noticeable for neighborhood residents. Tree removal due to ALB infestation in two residential neighborhoods in Worcester, Massachusetts in the winter of 2008-2009 resulted in a 37% increase (t = -9.09, p<0.001) in baseline-corrected, weather-normalized electrical consumption from the 2008 to 2009 cooling seasons. In Springfield, Massachusetts we find no difference in baseline-corrected, weather-normalized natural gas consumption for the heating season for individual homes after the June 1, 2011 tornado. The results of this research will aid in the development and implementation of energy conserving treeplanting and retention programs and policies pursuant to the Clean Energy and Climate Change Plan of 2010 in Massachusetts.

La synthèse d'une flamme animée dans un environnement 3D virtuel, reste à ce jour une tâche ardue, exigeant de judicieusement balancer réalisme et coût de calcul. Dans ce mémoire, nous présentons un ensemble de techniques pour sa simulation en temps réel tout en modélisant une interaction à des forces externes. Nous désirons minimiser son coût de calcul tout en préservant une apparence convaincante dans l'optique d'une intégration au sein de systèmes existants, n'affectant pas indûment leurs performances. Un champ de vélocité est extrait d'une simulation de ressorts et mis à profit dans le déplacement de chaînes de particules modélisant la forme de la flamme par l'entremise de la paramétrisation d'une surface NURBS. Considérant l'importance qu'ils ont sur notre perception de la combustion, nous prenons également soin de reproduire l'illumination, les ombres, et l'effet d'éblouissement qu'elle engendre.
The synthesis of an open flame in a virtual 3D environment, remains to this day an arduous task, requiring a wise balance between realism and processing cost. In this M. Sc. thesis, we present a set of techniques for its simulation in real time while also modeling the interaction with external forces. Our goal is to minimize the cost while preserving a convincing appearance, thus facilitating integration of the techniques into existing systems without unduly affecting their performance. A velocity field is extracted from a spring-mass simulation which contributes to moving chains of particules that are used in modeling the flame shape through the configuration of a NURBS surface. In light of the importance they have on our perception of combustion, we also take care to duplicate the lighting, shadows and bloom the flame gives rise to.
Vidéos et images des résultats disponible à : http://www.iro.umontreal.ca/labs/infographie/theses/fatnasss/