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Waste from construction and demolition-building activities is increasing every day. Landfills have almost reached their capacity. When thinking about the negative impact of demolishing activities on the environment it becomes very necessary to think about reusing and recycling building materials in new construction or perhaps better recycling our thoughts on how to make use of waste materials. In Kevin Lynch's book, Wasting Away, he wrote: "Architects must begin to think about holes in the ground and about flows of materials." Studies show that construction and demolition activities are the primary source of solid waste worldwide. For example construction and demolition wastes constitute about 40% of the total solid waste stream in the United States. The growing interest in materials and resource conservation in the United States is inherent in the growth of green building practices. The USGBC identifies six categories in the Materials and Resources (MR) section of LEED. One of these six categories is Resource Reuse (RR). Interestingly enough, a recent study about the cost of green buildings indicated that RR was the category credits least often achieved in most LEED certified projects. Literature suggests that there are a number of constraints and barriers to resource reuse primarily due to the complexity of buildings but perhaps the most important barrier, according to many architects, is the lack of easily accessible information to the design team on resource reuse. Therefore, as we promote the idea of building material reuse to a wider audience of designers and architects, we mus not forget that in the Architecture, Engineering and Construction (AEC) industry, both Reuse and Recycle terms are used interchangeably without yet a clear distinction between them. The use of arbitrary descriptions to distinguish reuse from recycle has caused nothing but more confusion to the public. This study argues that the real distinction between reuse and recycle exists in Knowledge and Information. This suggests that design with reuse requires a paradigm shift in the required knowledgebase and the way information flows within the design process. Unfortunately, the structure of this paradigm shift is not known and has not been well defined. Since knowledge forms the core of building a Decision Support Systems (DSS) for a design team in order to consider reuse, it is necessary to capture the required knowledge and information from the industry experts through a Knowledge Acquisition (KA) process. This knowledge can then be used to 1) identify the building material reuse criteria and 2) to build a prescriptive decision model and 3) to map the process design of the current traditional architectural design workflow and the proposed one. The overarching goal of this study is to use the building material reuse knowledgebase for 1) building a Unified Virtual Repository database to be connected to all available physical repositories and share a unified standard of information. 2) When the unified virtual repository is integrated with the Building Information Modeling (BIM) database, the DSS can work as a feedback and feed forward support for architects and designers as they consider building material reuse in new designs and constructions. / Ph. D.

In the field of sustainable architecture, transformability is an important way of actively responding to ambient conditions while also meeting the needs of occupants and addressing issues of building performance. This research contributes knowledge for architects about the potential of kinetics for the shading system to respond effectively to changes in its environment. Within contemporary architecture, there is a growing interest in motion; buildings and their parts are gradually shifting from static to dynamic. However, contemporary activities in architecture are evidence of a lack of a holistic approach to the design of motion in architecture and the design of motion as an alternative mode of design thinking is still in its infancy. Consequently, the existing tradition of static forms being the sole forms taught in architectural studies should be reevaluated as a design strategy. This research is a step in the direction of better understanding the key knowledge exchanges within the design process of transformable shading systems. It will seek to investigate, explore, and propose how the concept of transformability in designing shading systems can be suggested, depicted, or physically incorporated in building envelopes. In order to get the full potential of the design process of transformable shading systems, this study presents a design workflow of a specific case, called AURA, that helps to create openings for establishing a proper design methodology of transformable shading systems. While the workflow will be concerned with identifying the key decision nodes, it is anticipated that in-depth development will determine critical parameters addressing transformation itself as a design parameter of transformable shading systems. Two studio-based courses offered at Virginia Tech and Texas AandM by the author will become a testing ground for evaluating the key decision nodes found in the design process of AURA within the context of architectural programs, bringing forth the opportunity to expand the current domain of transformable shading systems to a broader perspective of architecture pedagogy. In this case, this research is a step towards adding values directly into the content of the curricula, and thus into the field of design education as a whole.' / Ph. D.

Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2008. / Thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Civil Engineering at the University of Stellenbosch. / ENGLISH ABSTRACT: The logical scheduling of activities in an engineering project currently relies heavily on the experience and intuition of the persons responsible for the schedule. In large projects the complexity of the schedule far exceeds the capacity of human intuition, and systematic techniques are required to compute a consistent sequence of activities. In this study a simple model of the engineering process is described. Based on certain specified relationships between components of the model, a consistent sequence of activities is determined in the form of a logical step schedule. The problem of resource constraints receives special attention. Engineering projects are often executed with limited resources and determining the impact of such restrictions on the logical step schedule is important. This study investigates activityshifting strategies to find a near-optimal sequence of activities that guarantees consistent evolution of deliverables while resolving resource conflicts within the context of logical step schedules. / AFRIKAANSE OPSOMMING: Die logiese skedulering van aktiwiteite in ‘n ingenieursprojek steun swaar op die ondervinding en intuisie van die persone wat verantwoordelik is vir die skedule. In groot projekte is die kompleksiteit van die skedule veel hoër as die kapasiteit van die menslike intuisie, en sistematiese tegnieke word benodig om ‘n konsekwente volgorde van aktiwiteite te bereken. In hierdie studie word ‘n eenvoudige model van die ingenieursproses beskryf. Gebasseer op sommige relasies tussen komponente van die model, kan ‘n konsekwente volgorde van aktiwiteite bepaal word in die vorm van ‘n logiese stap-skedule. Die probleem van beperkte hulpbronne ontvang spesiale aandag. Ingenieursprojekte word dikwels uitgevoer met beperkte hulpbronne en dit is belangrik om die impak daarvan op die logiese stap-skedule te bepaal. Die studie ondersoek die gebruik van aktiwiteit-skuiwende strategieë om ‘n nabyoptimale volgorde van aktiwiteite te vind wat konsekwente ontwikkeling van die projekprodukte waarborg, terwyl hulpbron konflikte opgelos word binne die konteks van ‘n logiese stap-skedule.

Esta Tese está dividida em três volumes: I - Croqui: representação e simulação II - O desenho e o processo de projeto III - O ensino do desenho para arquitetos Os três volumes tratam do mesmo objeto de estudo: o desenho do arquiteto e para a arquitetura, mas sob um enfoque diverso. No Volume I, além de uma abordagem teórica sobre as premissas metodológicas, o desenho é visto sob três outros enfoques: enquanto conceito relativo à problemática inerente à arquitetura, ou seja, representação e simulação do espaço; enquanto instrumento de projeto adaptado a cada momento da arquitetura; e também enquanto objeto artístico. No Volume II, estreita-se a relação entre desenho e projeto de arquitetura, tentando estabelecer relações entre um e outro método. São apresentados os resultados do acompanhamento e análise do trabalho de vários arquitetos, bem como entrevistas, na íntegra, com os arquitetos Paulo Mendes da Rocha, Joaquim Guedes e Abrahão Sanovicz. No Volume III, o ensino do desenho tem destaque com base nas teorias da escola ativa, os métodos de ensino-aprendizagem e sua adaptação ao universo da arquitetura. Nos três volumes, a intenção principal é sempre verificar os pressupostos básicos para o ensino de desenho para futuros arquitetos. Os três volumes são permeados por conclusões inerentes ao enfoque sobre o qual se referem. No final do terceiro volume, apresenta-se uma conclusão sobre o enfoque geral, tratado nos três volumes, relacionando imagem, desenho e projeto para fins didáticos. / This Thesis is divided in three volumes: I - Croquis: representation and simulation II - Design and process of the project III - Teaching of the design to architects The three volumes deal with the same object to study: the design of architect and to architecture, but under a different focus. In the first volume, besides a theoretical aproach about the metodological premisses, the design is seen under three other focuses: as a concept conected to the problematic inherente to the architecture, I mean, representation and simulation of the space; whereas instrument of the project adapted to each moment of the architecture; and even as artistic object. In the volume II, narrows the conection between design and project of architecture, trying to stablish conexions between one and other method. Here are presented the results of the attendance and analyse of the work of various architects, as well as briefinga, as a whole, with the architects Paulo Mendes da Rocha, Joaquim Guedes and Abrahão Sanovicz. In the volume III, the teaching of the design has a prominence based in the theories of the active school, the methods of teaching-apprenticeship and its adaptation to the architecture universe. In the three volumes, the main target is always verify the basic pressuposed to the teaching to the future architects. The three volumes are interposed by conclusions inherents to the focus on which they refer. At the end of the third volume, we present a conclusion about the general focused, treated in the three volumes, linking image, drawing and project to didacts aims.

Nowadays, computers are extensively used in engineering modeling and simulation fields in many different ways, one of which is in chemical engineering. Simulation and modeling of a chemical process plant and the sizing of the equipment with the assistance of computers, is of special interests to process engineers and investors. This is due to the ability of high speed computers, which make millions of mathematical calculations in less than a second associated with the new powerful software that make the engineering calculations more reliable and precise by making very fast iterations in thermodynamics, heat and mass transfer calculations. This combination of new technological hardware and developed software enables process engineers to deal with simulation, design, optimization, control, analysis etc. of complex plants, e.g. refinery and petrochemical plants, reliably and satisfactorily. The main chemical process simulators used for static and dynamic simulations are ASPEN PLUS, ASPEN HYSYS, PRO II, and CHEMCAD. The basic design concepts of all simulators are the same and one can fairly use all simulators if one is expert in any of them. Hydrogenation process is an example of the complex plants, to which a special attention is made by process designers and manufacturers. This process is used for upgrading of hydrocarbon feeds containing sulfur, nitrogen and/or other unsaturated hydrocarbon compounds. In oil and gas refineries, the product of steam cracking cuts, which is valuable, may be contaminated by these unwanted components and thus there is a need to remove those pollutants in downstream of the process. Hydrogenation is also used to increase the octane number of gasoline and gas oil. Sulfur, nitrogen and oxygen compounds and other unsaturated hydrocarbons are undesired components causing environmental issues, production of by-products, poisoning the catalysts and corrosion of the equipment. The unsaturated C=C double bonds in dioleffinic and alkenyl aromatics compounds, on the other hand, cause unwanted polymerization reactions due to having the functionality equal to or greater than 2. Hydrogenation process of the undesired components will remove those impurities and/or increase the octane number of aforementioned hydrocarbons. This process is sometimes referred to as “hydrotreating”; however, “upgrader” is a general word and is, of course, of more interest. In this thesis, a hydrogenation process plant was designed on the basis of the chemistry of hydrocarbons, hydrogenation reaction mechanism, detailed study of thermodynamics and kinetics and then a steady-state simulation and design of the process is carried out by ASPEN HYSYS 2006 followed by design evaluation and some modifications and conclusions. Hydrogenation reaction has a complicated mechanism. It has been subjected to hot and controversial debates over decades. Many kinetic data are available, which contradict one another. Among them, some of the experimental researches utilize good assumptions in order to simplify the mechanism so that a “Kinetic Reaction” modeling can be employed. This thesis takes the benefit of such research works and applies some conditions to approve the validity of those assumptions. On the basis of this detailed study of reaction modeling and kinetic data, a hydrogenation plant was designed to produce and purify over 98 million kilograms of different products; e.g. Benzene, Toluene, Iso-octane etc. with fairly high purity.

Nowadays, computers are extensively used in engineering modeling and simulation fields in many different ways, one of which is in chemical engineering. Simulation and modeling of a chemical process plant and the sizing of the equipment with the assistance of computers, is of special interests to process engineers and investors. This is due to the ability of high speed computers, which make millions of mathematical calculations in less than a second associated with the new powerful software that make the engineering calculations more reliable and precise by making very fast iterations in thermodynamics, heat and mass transfer calculations. This combination of new technological hardware and developed software enables process engineers to deal with simulation, design, optimization, control, analysis etc. of complex plants, e.g. refinery and petrochemical plants, reliably and satisfactorily. The main chemical process simulators used for static and dynamic simulations are ASPEN PLUS, ASPEN HYSYS, PRO II, and CHEMCAD. The basic design concepts of all simulators are the same and one can fairly use all simulators if one is expert in any of them. Hydrogenation process is an example of the complex plants, to which a special attention is made by process designers and manufacturers. This process is used for upgrading of hydrocarbon feeds containing sulfur, nitrogen and/or other unsaturated hydrocarbon compounds. In oil and gas refineries, the product of steam cracking cuts, which is valuable, may be contaminated by these unwanted components and thus there is a need to remove those pollutants in downstream of the process. Hydrogenation is also used to increase the octane number of gasoline and gas oil. Sulfur, nitrogen and oxygen compounds and other unsaturated hydrocarbons are undesired components causing environmental issues, production of by-products, poisoning the catalysts and corrosion of the equipment. The unsaturated C=C double bonds in dioleffinic and alkenyl aromatics compounds, on the other hand, cause unwanted polymerization reactions due to having the functionality equal to or greater than 2. Hydrogenation process of the undesired components will remove those impurities and/or increase the octane number of aforementioned hydrocarbons. This process is sometimes referred to as “hydrotreating”; however, “upgrader” is a general word and is, of course, of more interest. In this thesis, a hydrogenation process plant was designed on the basis of the chemistry of hydrocarbons, hydrogenation reaction mechanism, detailed study of thermodynamics and kinetics and then a steady-state simulation and design of the process is carried out by ASPEN HYSYS 2006 followed by design evaluation and some modifications and conclusions. Hydrogenation reaction has a complicated mechanism. It has been subjected to hot and controversial debates over decades. Many kinetic data are available, which contradict one another. Among them, some of the experimental researches utilize good assumptions in order to simplify the mechanism so that a “Kinetic Reaction” modeling can be employed. This thesis takes the benefit of such research works and applies some conditions to approve the validity of those assumptions. On the basis of this detailed study of reaction modeling and kinetic data, a hydrogenation plant was designed to produce and purify over 98 million kilograms of different products; e.g. Benzene, Toluene, Iso-octane etc. with fairly high purity.

In 1970&rsquo / s, significant shifts occurred both in planning and design theories as a response to the decreasing role of state in property relations and widening arena of private property. This shift in planning approaches led to an increase in the importance of &lsquo / flexibility&rsquo / concept. However this study proposes that flexibility in the control of spatial development is not an indisputable solution, but rather it is a dilemma. This is because / the definition, degree and effect of flexibility may change in every step of the process depending on the actors in the process. While it may be a way of solution in one case, it may be the problem itself in another. In the study, this dilemma is discussed in the context of spatial development in science parks. The concept of flexibility has a particular importance in respect to science parks which host especially technology based firms. Due to market changes and technology shifts, the spatial requirements of market and also the tenants change in time rapidly. That is why flexibility becomes a necessary tool in the physical planning of science parks. In this context, firstly the role flexibility in different planning and decision-making approaches is discussed. Then the structural characteristics of science parks and specifically METU Technopolis are defined. Within this framework, the physical development process of METU Technopolis and the role of flexibility in planning and decision making processes is examined. Finally some suggestions for controlling the flexibility in planning and design processes are developed.

Combination of high strength with light weight which is the prominent property of aluminum alloy forgings has led aluminum forgings used in rapidly expanding range of applications. In this study, to produce a particular 7075 aluminum alloy part, the forging process has been designed and analyzed. The forging process sequence has been designed by using Finite Volume Method. Then, the designed process has been analyzed by using Finite Element Method and the stress, strain and temperature distributions within the dies have been determined. Five different initial temperatures of the billet / 438, 400, 350, 300 and 250 degree Celsius have been considered in the thermo-mechanically coupled simulations. The initial temperatures of the dies have been taken as 200 degree Celsius for all these analyses. Finite volume analysis and finite element analysis results of the preform and finish part have been compared for the initial billet temperature of 400 oC. Close results have been observed by these analyses. The experimental study has been carried out for the range of the initial billet temperatures of 251&amp / #8211 / 442 degree Celsius in METU-BILTIR Center Forging Research and Application Laboratory. It has been observed that the numerical and the experimental results are in good agreement and a successful forging process design has been achieved. For the initial die temperature of 200 degree Celsius, to avoid the plastic deformation of the dies and the incipient melting of the workpiece, 350 degree Celsius is determined to be the appropriate initial billet temperature for the forging of the particular part.