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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.
121

Energy efficient design in housing of small floor area : appropriateness in housing for the aged

Karol, Elizabeth January 2003 (has links)
This thesis seeks to address energy efficient design in a temperate climate in typical small, medium density housing, particularly in housing for the aged. The connections between energy efficient design and small, medium density housing were identified as contemporary issues related to Australian Government policies in two disparate areas. One policy area is reflected in the Government's commitment to assist older people, whether they are active, early retirees or the frail elderly, wealthy or poor, to live in their chosen place of residence. Increasingly this chosen place of residence may be a small, medium density dwelling. The other policy area is that related to reducing energy consumption in buildings. This policy is reflected in recently proclaimed building regulations aimed at reducing space heating/cooling requirements in housing. The building regulations include details of acceptable construction practice for energy efficiency that may not be appropriate in small, medium density housing. It was proposed in this thesis that extensive use of space heating and cooling in housing for the aged was required because well-established benchmarks for energy efficient design in a temperate climate were not generally appropriate in small, medium density dwellings and were particularly inappropriate in housing for the aged. `Appropriate' in this context referred to: indoor temperatures being acceptable without the need for space heating and cooling; retaining the site planning and general form of typical, medium density aged persons housing developments in suburban Australia; cost effectiveness over the life of a building; and fitting the needs of physically and financially vulnerable older people. / The methods used to examine the notion of appropriateness commenced with a literature review that related to the general physical and economic status of older people and their needs and responses to space heating and cooling in the home. Further, the literature review considered the principles of energy efficient design and benchmark criteria for energy efficiency. Arising from the literature review, two tools of study were used in order to develop a set of data encapsulating the salient features of small, medium density housing. The first was a multiple case study of typical housing for the aged. This was conceived as a way of determining if small, medium density dwellings could provide appropriate indoor thermal conditions and/or were designed to be energy efficient. The indoor temperatures were monitored in summer and winter and annual energy consumption was established and statistically analysed. The building designs were analysed in terms of their orientation, glazing areas, wall areas, volumes of thermal mass and ventilation capacity and compared with benchmarks for energy efficient design. The second tool involved a series of computer simulations of a typical small, medium density dwelling. The simulation process was utilised to determine if a new set of benchmarks for energy efficient small, medium density dwellings were required that would incorporate the notion of appropriateness. From the multiple case study it was found that, irrespective of design, indoor temperatures in 98% of dwellings were above the acceptable maximum summer temperature of 27.4°C in still air and indoor temperatures in all dwellings were found to be below the acceptable minimum daytime temperature of 19.8°C. / The findings also showed that some aspects of the benchmarks for energy efficient design were not appropriate in typical, medium density housing constructed specifically for the aged. From the simulation process it was discovered that acceptable temperatures could be achieved in small medium density housing if the principles of energy efficient design, incorporated within a new set of benchmarks, were integrated with appropriateness criteria for housing for the aged. The approach taken with the new benchmarks was to create both performance based and prescriptive design solutions. The performance model differs from the current benchmarks for energy efficient design in that it establishes key functional objectives for energy efficient design. Compared to the current benchmarks, the prescriptive design solutions show significant reductions in the areas of northerly glazing and total glazing. To compensate for the reduced area of northerly glazing, both direct and indirect means of solar gain are utilised for passive heating. The thesis outcomes have implications for three areas of the construction industry. The prescriptive design solutions presented in building regulations for energy efficiency in housing need to be qualified, the design briefs prepared for energy efficient construction of small, medium density housing need amendment and the approach taken by designers involved in energy efficient small, medium density housing needs to be reconsidered.
122

Criteria for the Design and Evaluation of Technology Education Facilities: A Study Involving the Development and Trial of Appropriate Design Criteria

Wheeler, Brian James, n/a January 1997 (has links)
As education systems, in particular Technology Education, adapt to new expectations for secondary students entering an uncertain workforce, the time is appropriate to investigate the need for school facilities to meet these present demands and those that continue to change curricula. This study has been conducted in order to determine the facility requirements for the delivery of the evolving technology/manual arts curriculum in Queensland. A set of validated design criteria for evaluating technology education and vocational education settings was developed and trialed to assist the designer of such facilities to meet the needs of this area on schools designed in different eras from the 1 960s to the present. A review of the published literature would indicate that little has been written on this aspect of facilities design. While related studies have been conducted in North America, they were not confined to the designing of the facilities and only had specific relevance in that country. An expert group consisting of prominent Queensland educators provided the impetus for developing the criteria which had been generated through a systematic search of the literature. The methodology utilised to involve the expert group was the Nominal Group Technique. After the criteria had been developed, they were validated by questionnaire through a 30% random sample of practicing heads of department across Queensland in both state and independent systems. A trial evaluation using current facilities was subsequently conducted to determine the effectiveness of the criteria in terms of teacher acceptability as well as establishing a pattern of needs for modification. Practitioners who use the facility for teaching technology education and/or vocational education could use the set of criteria to evaluate their facility in a similar manner to that of evaluating their students. Such evaluations could then become the basis for ffiture school planning and budgetary allocations as well as asset management of existing facilities. The study proved to be valuable as the validated criteria have the potential of being used as a tool by teachers to evaluate their facilities. At the systems level of operation, the criteria will provide assistance for designers, architects and teachers to prepare informal educational briefs. Such briefs would provide a consistent approach to the some times difficult task of clearly defining the function of a facility. The modem facility must meet the needs of current curriculum and be sufficiently flexible and adaptable to provide the educational requirements well into the twenty-first century. These developed criteria will greatly assist in this process.
123

Salinity hazard mapping and risk assessment in the Bourke irrigation district

Buchannan, Sam, Faculty of Science, UNSW January 2008 (has links)
At no point in history have we demanded so much from our agricultural land whilst simultaneously leaving so little room for management error. Of the many possible environmental impacts from agriculture, soil and water salinisation has some of the most long-lived and deleterious effects. Despite its importance, however, land managers are often unable to make informed decisions of how to manage the risk of salinisation due to a lack of data. Furthermore, there remains no universally agreed method for salinity risk mapping. This thesis addresses these issues by investigating new methods for producing high-resolution predictions of soil salinity, soil physical properties and groundwater depth using a variety of traditional and emerging ancillary data sources. The results show that the methodologies produce accurate predictions yielding natural resource information at a scale and resolution not previously possible. Further to this, a new methodology using fuzzy logic is developed that exploits this information to produce high-resolution salinity risk maps designed to aid both agricultural and natural resource management decisions. The methodology developed represents a new and effective way of presenting salinity risk and has numerous advantages over conventional risk models. The incorporation of fuzzy logic provides a meaningful continuum of salinity risk and allows for the incorporation of uncertainty. The method also allows salinity risk to be calculated relative to any vegetation community and shows where the risk is coming from (root-zone or groundwater) allowing more appropriate management decisions to be made. The development of this methodology takes us a step closer to closing what some have called our greatest gap in agricultural knowledge. That is, our ability to manage the salinity risk at the subcatchment scale.
124

Selection procedures relating to Australian vocal repertoire for mid-adolescent HSC performers.

Dixon, Wendy P January 2007 (has links)
Master of Music (Music Education) / This thesis documents an investigation of the selection procedures relating to Australian vocal repertoire for mid-adolescent and Higher School Certificate (New South Wales) performers, as used by private singing teachers, school music teachers and singing students. It explores the similarities and differences in the criteria employed in these selections. Semi-structured interviews were the source of data and were conducted with participants from these three categories as well as two composers. The participants evinced highly disparate views. The private singing teachers believed that repertoire should be dictated by the technical ability and physiological constraints of mid-adolescent students and that their role in selecting repertoire was related to the long term vocal growth of each individual. They felt that the school music teachers vetted their repertoire choices with no useful explanation of their reasoning, while the school music teachers noted that students frequently presented repertoire that was too difficult or that was not readily communicated with the audience. The ability of mid-adolescent singers to communicate with and engage an audience was the prime concern of the school music teachers. The students wanted to impress their examiners and believed that infrequently heard repertoire was the best choice, though this was not endorsed by the teachers. There was a perception that the students would perform at their best when they chose repertoire to which they could relate emotionally. Many private singing teachers and school music teachers are not aware of the very broad range of contemporary Australian music and its divergent characteristics. However, there is a shortage of appropriate Australian repertoire that addresses the physiological and emotional needs of mid-adolescent singers.
125

Evolutionary structural optimisation as a robust and reliable design tool

Proos, Kaarel Andres January 2002 (has links)
Evolutionary Structural Optimisation (ESO) is a relatively new design tool used to improve and optimise the design of structures. It is a heuristic method where a few elements of an initial design domain of finite elements are iteratively removed. Such a process is carried out repeatedly until an optimum design is achieved, or until a desired given area or volume is reached. There have been many contributions to the ESO procedure since its conception back in 1992. For example, a provision known as Bi-Directional ESO (BESO) has now been incorporated where elements may not only be removed, but added. Also, rather than deal with elements where they are either present or not, the designer now has the option to change the element's properties in a progressive fashion. This includes the modulus of elasticity, the density of the material and the thickness of plate elements, and is known as Morphing ESO. In addition to the algorithmic aspects of ESO, a large preference exists to optimise a structure based on a selection of criteria for various physical processes. Such examples include stress minimisation, buckling and electromagnetic problems. In a changing world that demands the enhancement of design tools and methods that incorporate optimisation, the development of methods like ESO to accommodate this demand is called for. It is this demand that this thesis seeks to satisfy. This thesis develops and examines the concept of multicriteria optimisation in the ESO process. Taking into account the optimisation of numerous criteria simultaneously, Multicriteria ESO allows a more realistic and accurate approach to optimising a model in any given environment. Two traditional methods � the Weighting method and the Global Criterion (Min-max) method have been used, as has two unconventional methods � the Logical AND method and the Logical OR method. These four methods have been examined for different combinations of Finite Element Analysis (FEA) solver types. This has included linear static FEA solver, the natural frequency FEA solver and a recently developed inertia FE solver. Mean compliance minimisation (stiffness maximisation), frequency maximisation and moment of inertia maximisation are an assortment of the specific objectives incorporated. Such a study has provided a platform to use many other criteria and multiple combinations of criteria. In extending the features of ESO, and hence its practical capabilities as a design tool, the creation of another optimisation method based on ESO has been ushered in. This method concerns the betterment of the bending and rotational performance of cross-sectional areas and is known as Evolutionary Moment of Inertia Optimisation (EMIO). Again founded upon a domain of finite elements, the EMIO method seeks to either minimise or maximise the rectangular, product and polar moments of inertia. This dissertation then goes one step further to include the EMIO method as one of the objectives considered in Multicriteria ESO as mentioned above. Most structures, (if not all) in reality are not homogenous as assumed by many structural optimisation methods. In fact, many structures (particularly biological ones) are composed of different materials or the same material with continually varying properties. In this thesis, a new feature called Constant Width Layer (CWL) ESO is developed, in which a distinct layer of material evolves with the developing boundary. During the optimisation process, the width of the outer surrounding material remains constant and is defined by the user. Finally, in verifying its usefulness to the practical aspect of design, the work presented herein applies the CWL ESO and the ESO methods to two dental case studies. They concern the optimisation of an anterior (front of the mouth) ceramic dental bridge and the optimisation of a posterior (back of the mouth) ceramic dental bridge. Comparisons of these optimised models are then made to those developed by other methods.
126

Approaches to Selecting Information Systems Projects under Uncertainty

Wibowo, Santoso, s3037939@student.rmit.edu.au January 2008 (has links)
The rapid advance in information and communication technologies has effectively facilitated the development and implementation of information systems (IS) projects in modern organizations for reorganizing their business processes and streamlining the provision of their products and services in today's dynamic environment. Such a development brings organizations with numerous benefits including increased automation of business processes, improved customer service, and timely provision of effective decision support. As a result, evaluating and selecting the most appropriate IS project for development and implementation from a pool of available IS projects becomes a critical decision to make in modern organizations. Evaluating and selecting appropriate IS projects for development in an organization, however, is complex and challenging. The complexity of the evaluation and selection process is due to the multi-dimensional nature of the decision making process, the conflicting nature of the multiple selection criteria, and the presence of subjectiveness and imprecision of the human decision making process. The challenging of the evaluation and selection comes from the need for making transparent and balanced decisions based on a comprehensive evaluation of all available IS projects in a timely manner. Much research has been done on the development of various approaches for evaluating and selecting IS projects, and numerous applications of those approaches for addressing real world IS project evaluation and selection problems have been reported in the literature. In general, existing approaches can be classified into (a) cost-benefit analysis based approaches, (b) utility based approaches, and (c) optimization oriented approaches. These approaches, however, are not totally satisfactory due to various shortcomings including (a) the inability to tackle the subjectiveness and imprecision of the selection process, (b) the failure to adequately handle the multi-dimensional nature of the problem, and (c) cognitively very demanding on the decision maker. To address these issues above, this research has developed three novel approaches for effectively solving the IS project evaluation and selection problem under uncertainty in an organization. The first approach is developed for helping the decision maker better model the subjectiveness and imprecision inherent in the decision-making process with the use of linguistic variables approximated by fuzzy numbers. The second approach is designed to reduce the cognitive demanding on the decision maker in the IS project evaluation and selection process with the introduction of fuzzy pairwise comparison. The third approach is formulated with respect to the use of intelligent decision support systems for facilitating the use of specific multi-criteria analysis approaches in relation to individual IS project evaluation and selection situations. The developed approaches have been applied for solving three IS project evaluation and selection problems in the real world settings. The results show that the three developed ap proaches are of practical significance for effectively and efficiently solving the IS project evaluation and selection problem due to (a) the simplicity and comprehensibility of the underlying concept, (b) the adequate handling of inherent uncertainty and imprecision, and (c) the ability to help the decision maker better understand the IS project selection problem and the implications of their decision behaviours.
127

Multi-Criteria Planning of Local Energy Systems with Multiple Energy Carriers

Løken, Espen January 2007 (has links)
<p>Background and Motivation</p><p>Unlike what is common in Europe and the rest of the world, Norway has traditionally met most of its stationary energy demand (including heating) with electricity, because of abundant access to hydropower. However, after the deregulation of the Norwegian electricity market in the 1990s, the increase in the electricity generation capacity has been less than the load demand increase. This is due to the relatively low electricity prices during the period, together with the fact that Norway’s energy companies no longer have any obligations to meet the load growth. The country’s generation capacity is currently not sufficient to meet demand, and accordingly, Norway is now a net importer of electricity, even in normal hydrological years. The situation has led to an increased focus on alternative energy solutions.</p><p>It has been common that different energy infrastructures – such as electricity, district heating and natural gas networks – have been planned and commissioned by independent companies. However, such an organization of the planning means that synergistic effects of a combined energy system to a large extent are neglected. During the last decades, several traditional electricity companies have started to offer alternative energy carriers to their customers. This has led to a need for a more comprehensive and sophisticated energy-planning process, where the various energy infrastructures are planned in a coordinated way. The use of multi-criteria decision analysis (MCDA) appears to be suited for coordinated planning of energy systems with multiple energy carriers. MCDA is a generic term for different methods that help people make decisions according to their preferences in situations characterized by multiple conflicting criteria.</p><p>The thesis focuses on two important stages of a multi-criteria planning task:</p><p>- The initial structuring and modelling phase</p><p>- The decision-making phase</p><p>The Initial Structuring and Modelling Phase</p><p>It is important to spend sufficient time and resources on the problem definition and structuring, so that all disagreements among the decision-maker(s) (DM(s)) and the analyst regarding the nature of the problem and the desired goals are eliminated. After the problem has been properly identified, the next step of a multi-criteria energy-planning process is the building of an energy system model (impact model). The model is used to calculate the operational attributes necessary for the multi-criteria analysis; in other words, to determine the various alternatives’ performance values for some or all of the criteria being considered. It is important that the model accounts for both the physical characteristics of the energy system components and the complex relationships between the system parameters. However, it is not propitious to choose/build an energy system model with a greater level of detail than needed to achieve the aims of the planning project.</p><p>In my PhD research, I have chosen to use the eTransport model as the energy system model. This model is especially designed for planning of local and regional energy systems, where different energy carriers and technologies are considered simultaneously. However, eTransport can currently provide information only about costs and emissions directly connected to the energy system’s operation. Details about the investment plans’ performance on the remaining criteria must be found from other information sources. Guidelines should be identified regarding the extent to which different aspects should be accounted for, and on the ways these impacts can be assessed for each investment plan under consideration. However, it is important to realize that there is not one solution for how to do this that is valid for all kind of local energy-planning problems. It is therefore necessary for the DM(s) and the analyst to discuss these issues before entering the decision-making phase.</p><p>The Decision-Making Phase</p><p>Two case studies have been undertaken to examine to what extent the use of MCDA is suitable for local energy-planning purposes. In the two case studies, two of the most well-known MCDA methods, the Multi-Attribute Utility Theory (MAUT) and the Analytical Hierarchy Process (AHP), have been tested. Other MCDA methods, such as GP or the outranking methods, could also have been applied. However, I chose to focus on value measurement methods as AHP and MAUT, and have not tested other methods. Accordingly, my research cannot determine if value measurement methods are better suited for energy-planning purposes than GP or outranking methods are.</p><p>Although all MCDA methods are constructed to help DMs explore their ‘true values’ – which theoretically should be the same regardless of the method used to elicit them – our experiments showed that different MCDA methods do not necessarily provide the same results. Some of the differences are caused by the two methods’ different ways of asking questions, as well as the DMs’ inability to express clearly their value judgements by using one or both the methods. In particular, the MAUT preference-elicitation procedure was difficult to understand and accept for DMs without previous experience with the utility concept. An additional explanation of the differences is that the external uncertainties included in the problem formulation are better accounted for in MAUT than in AHP. There are also a number of essential weaknesses in the theoretical foundation of the AHP method that may have influenced the results using that method. However, the AHP method seems to be preferred by DMs, because the method is straightforward and easier to use and understand than the relatively complex MAUT method.</p><p>It was found that the post-interview process is essential for a good decision outcome. For example, the results from the preference aggregation may indicate that according to the DM’s preferences, a modification of one of the alternatives might be propitious. In such cases, it is important to realize that MCDA is an iterative process. The post-interview process also includes presentation and discussion of results with the DMs. Our experiments showed that the DMs might discover inconsistencies in the results; that the results do not reflect the DM’s actual preferences for some reason; or that the results simply do not feel right. In these cases, it is again essential to return to an earlier phase of the MCDA process and conduct a new analysis where these problems or discrepancies are taken into account.</p><p>The results from an MAUT analysis are usually presented to the DMs in the form of expected total utilities given on a scale from zero to one. Expected utilities are convenient for ranking and evaluation of alternatives. However, they do not have any direct physical meaning, which quite obviously is a disadvantage from an application point of view. In order to improve the understanding of the differences between the alternatives, the Equivalent Attribute Technique (EAT) can be applied. EAT was tested in the first of the two case studies. In this case study, the cost criterion was considered important by the DMs, and the utility differences were therefore converted to equivalent cost differences. In the second case study, the preference elicitation interviews showed, quite surprisingly, that cost was not considered among the most important criteria by the DMs, and none of the other attributes were suitable to be used as the equivalent attribute. Therefore, in this case study, the use of EAT could not help the DMs interpreting the differences between the alternatives.</p><p>Summarizing</p><p>For MCDA to be really useful for actual local energy planning, it is necessary to find/design an MCDA method which: (1) is easy to use and has a transparent logic; (2) presents results in a way easily understandable for the DM; (3) is able to elicit and aggregate the DMs' real preferences; and (4) can handle external uncertainties in a consistent way.</p>
128

A Probabilistic Approach to Conceptual Sensor Modeling

Sonesson, Mattias January 2005 (has links)
<p>This report develops a method for probabilistic conceptual sensor modeling. The idea is to generate probabilities for detection, recognition and identification based on a few simple factors. The</p><p>focus lies on FLIR sensors and thermal radiation, even if discussions of other wavelength bands are made. The model can be used as a hole or some or several parts can be used to create a simpler model. The core of the model is based on the Johnson criteria that uses resolution as the input parameter. Some extensions that models other factors are also implemented. In the end a short discussion of the possibility to use this model for other sensors than FLIR is made.</p>
129

Introducing GIS and Multi-criteria analysis in road path planning process in Nigeria : A case study of Lokoja, Kogi State

Anavberokhai, Isah January 2008 (has links)
<p>In planning a suitable road network, planners put into consideration factors like gradients or slope of the area, available land-use and soil type, community or national landmarks and governmental interest. These different considerations and interest make the planning process complex and as such there might be confusion of interest in the decision making. The use of GIS and Multi-criteria analysis has helped planners to achieve desired and more accurate results and as such reducing the complex nature in the planning process allowing different stakeholders to reach a general conclusion.</p><p>Multi-criteria analysis (MCA) prevents the imposition of limit on the form of criteria and gives opportunity to decision makers to enter their own judgments. This provides a better communication among the decision makers and the entire community and as such creating a more open choice for analysis and possible changes if necessary. The aim of this thesis is to introduce the possibility of using GIS and MCA in road path planning in Nigeria, using Lokoja, the capital of Kogi state as a case study.</p><p>In actualizing the aim, satellite images of the area of study was obtained from the Landsat home page and analyzed to derive the land-use map. The land-use over the area of study was classified into five different classes using the unsupervised method of classification. A DEM over the area of study was downloaded from the website of the Consortium of Spatial information (CSI) and the DEM was used to derive the slope map over the area of study and the analytic hierarchy process (AHP) method was used in weighting the criterions according to preference.</p><p>As the conclusion of the analysis, a road path between two points was obtained. The start point of the road was located on an approximate coordinate of 219002, 958986 meters and the destination point on an approximate coordinate of 320322, 878101 meters. The start and destination point were selected randomly without any pre-knowledge of the area. The thesis has succeeded in showing that it is possible to determine a road path between two points using Geographic information system (GIS) and Multi-criteria analysis in Nigeria.</p>
130

Vad är viktigast i staden? : Utveckling av ett lokaliseringsverktyg för stadsplanering

Almlöf, Erik January 2010 (has links)
<p>This paper is part of the research programme ViSuCity, a programme with the goal of creating more sustainable urban planning through the development of better visual tools, which ultimately means better communication between various parties of public planning. The paper concerns the implementation of MCE into a 3D program for visualization. Multi criteria evaluation (MCE) is a technique that has been developed during the last 20 years. It merges GIS with AHP, forming a decision making tool for localization of, for example, new buildings.The result is an automated tool that enables advanced analysis of geographic areas.The tool has a very high potential due to the completely automated MCE and it is adapted for people without a technical background, let alone formal training in MCE. It provides great opportunities to test different scenarios, something that should be an important advantage. The incorporation of MCE into 3D models has made it easier for users to relate the maps to reality, since a detailed 3D model is very easily understood in terms of geographical placement. A brand new feature that has not previously been used is the ability to import new objects and give feedback to the analysis. A summary of research on the MCE underlines the current situation, that relatively little research exists surrounding the use and demand of MCE. This paper unfortunately contributes to this fact since no user studies have been done due to lack of time. This is something future research should focus on.</p> / ViSuCity

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