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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.
411

Identification of Landscape Site Development Criteria and Compilation for Fossil Fuel Electric Power Plants Applied to a Critique of Huntington Canyon Power Plant, Huntington, Utah

Manns, Thomas Franklin, II 01 May 1974 (has links)
This thesis project will explore the landscape site development of fossil fuel steam electric stations as it is presently practiced by electric utility companies, to determine what architectural, engineering, aesthetic, and climatological problems are being created through the engineering requirements acting upon' the site during site development and construction phases of power stations. It will identify typical problem areas that can be resolved by the Landscape Architect through the practical application of landscape architecture principles, the design use and influence of plant material, topography, and the environment. Design criteria will then be formulated for the site development of steam electric stations. The design criteria thus gathered will be applied to a critique of Huntington Canyon Electric Power Plant to determine the effectiveness and degree of success of the criteria.
412

Etude d'astéroïdes géocroiseurs à l'origine des pluies de météores / Near Earth Asteroids associated with meteor showers

Dumitru, Bogdan Alexandru 26 September 2018 (has links)
Les météoroïdes, les astéroïdes et les comètes ont été en interaction permanente avec la Terre pendant son existence. Lorsqu'un objet, tel qu'une comète ou un astéroïde, tourne autour du Soleil, il peut laisser des fragments de matière derrière lui. Il y a une relation implicite entre les fragments et leurs corps parents. Le champ gravitationnel de la Terre capte les fragments et quelques fois le matériel extraterrestre est retrouvé au sol sous la forme des météorites. L'étude de ces objets et le lien entre eux peuvent aider à comprendre les conditions de formation et d'évolution du Système solaire, les conditions de développement de la vie sur Terre, les processus chaotiques dans le Système solaire, la sécurité de la Terre et peut-être, l'industrie spatiale.Tous les objets dans le Système solaire sont caractérisés par leurs orbites et les flux de météoroïdes ont des orbites similaires avec les objets qui les produisent. Pour cette raison, la méthode la plus courante d'identification du corps parental est basée sur les similarités des orbites, également appelées critères de discrimination ou critères-D. Dans mon travail, j'ai utilisé trois critères D-Criteria pour l'association des corps parents. Je définis un seuil pour chaque mesure en utilisant une nouvelle méthode de sélection de seuil. En outre, j'ai étudié les objets associés stabilité orbitale, dans le sens du temps de Lyapunov et leurs propriétés physiques. En raison des similitudes entre les flux de météorites et leurs corps parents, il est nécessaire que les associations appartiennent à la population d'astéroïdes géocroiseurs. L'observation de cette population d'objets est cependant difficile. La géométrie favorable pour les observations d'un géocroiseur est limité a trois ou cinq fois par siècle. Pour cette raison j'ai créé un programme d'observation, qui vise à obtenir des données physiques pour les objets associés qui n'ont pas de données physiques. Lors de mes recherches, j'ai pu associer 296 géocroiseurs à 28 pluies de météores; parmi eux, 73 astéroïdes satisfaisants les trois critères utilisés. Du point de vue dynamique, mon échantillon contient 82 % d'astéroïdes de type Apollo et 7 % sont classés comme potentiellement dangereux, 15,3 % sont sur des orbites cométaires et 84,3 % sur des orbites d'astéroïdes. Du point de vue des données physiques, j'ai trouvé deux astéroïdes qui sont des rotateurs rapides, donc ils ne peuvent pas générer de météores. D'un autre côté, j'ai également trouvé un astéroïde binaire associé et un astéroïde tumbling, des objets avec une forte probabilité d'être des corps parents. J'ai également réussi à trouver des similitudes entre 5 météorites et 5 astéroïdes associés avec des données physiques et j'ai obtenu des données d'observation pour trois astéroïdes associés. / Meteoroids, asteroids, and comets have been permanently interacting with Earthduring its existence. When an object, such as a comet or an asteroid, revolve around the Sun it may leave fragments of matter behind it and if this object is in Earth’s proximity, those fragments are gathered by the planet gravity. The study of these objects and the link between them can help in the understanding of the formation and evolution conditions of the Solar System, the conditions of developing the life on Earth, the chaotic processes in the Solar System, Earth security and maybe, in future, space industry.All objects within the Solar System are characterized by their orbits andthe meteoroid streams have similar orbits with the objects that produce them. For that reason the most common method of parent body identification is based onorbits similarities, also known as discrimination criteria or D-Criteria. In my work I used three D-Criteria metrics for parent body association. I set a threshold for each metric by using a new threshold selection method. Moreover, I investigated the associated objects orbital stability, in the Lyapunov time sense and their physical properties.Due to the similarities between meteoroid streams and their parent bodies,it is required for the associations to belong to Near Earth Asteroids population. But for this population is difficult to obtain data. The favorable geometry for these objects observations occurs five times per century. For this reason was created an observational program, that aims to obtain physical data for the associated objects that do not have physical data.My results consist from 296 asteroids that were associated with 28 meteorshowers, from which 73 asteroids satisfied all the criteria used. From the dynamical perspective, my sample contains 82% of Apollo asteroids and 7% are classified as potential hazardous, 15.3% are on cometary orbits and 84.3% are on asteroidal orbits. From the physical data perspective, I found two asteroids that are fast-rotators, therefore they can not generate meteors. On the other hand, I also found associated one binary asteroid and one tumbling asteroid, objects with a high probability of being parent bodies.I also managed to find similarities between 5 meteorites and 5 associatedasteroids with physical data and I obtained observational data for three associated asteroids.
413

Political bias in hiring : people consider political opponents as less hireable than others without weighting criteria to justify why

Wiberg, Karin January 2019 (has links)
Previous studies have shown that characteristics like gender and ethnicity can affect the possibility to be hired. Decisions in hiring may also be justified by weighting the importance of hiring criteria and can thus seem unbiased. In other areas, bias due to political affiliation have been noted to be even more pronounced than bias due to ethnicity. However, effects of candidates’ political affiliation in hiring are not equally researched. This study aimed to fill this blank. Participants (N= 283) were randomized to a between-subjects design; A third read a resumé from a candidate affiliating with the The Left Party, a third read a resumé from a candidate affiliating with The Sweden Democrats, a party at the right end of the spectrum, and a third read a resumé from a candidate with no political affiliation. After reading the resumés, participants evaluated the hireability of their candidate. They also stated which hiring criteria, experience or education, was considered most important in this evaluation. Results showed that participants evaluated candidates with divergent political affiliation from the own as less hireable than candidates with unknown political affiliation, or a politicalaffiliation more similar to the own. Cues of political affiliation may thus be a disadvantage for an individual, applying for a job. However, biased evaluations were not justified to seem unbiased by weighting criteria. It is suggested that social norms do not imply hiding political bias to the same degree as bias due to for example gender or ethnicity.
414

Selection criteria for loading and hauling equipment - open pit mining applications

Hardy, Raymond J January 2007 (has links)
Methods for estimating productivity and costs, and dependent equipment selection process, have needed to be increasingly reliable. Estimated productivity and costs must be as accurate as possible in reflecting actual productivity and costs experienced by mining operations to accommodate the long-term trend for diminishing commodity prices, For loading and hauling equipment operating in open pit mines, some of the interrelated estimating criteria have been investigated for better understanding; and, consequently, more reliable estimates of production and costs, also more effective equipment selection process. Analysis recognizes many of the interrelated criteria as random variables that can most effectively be reviewed, analyzed and compared in terms of statistical mathematical parameters. Emphasized throughout is the need for management of the cyclical loading and hauling system using conventional shovels/excavators/loaders and mining trucks to sustain an acceptable “rhythm” for best practice productivity and most-competitive unit-production costs. Outcomes of the research include an understanding that variability of attributes needs to be contained within acceptable limits. Attributes investigated include truck payloads, bucket loads, loader cycle time, truck loading time and truck cycle time. Selection of “ultra-class” mining trucks (≥ 290 -tonne payload) and suitable loading equipment is for specialist mining applications only. Where local operating environment and cost factors favourably supplement diminishing cost-benefits of truck scale, ultra-class trucks may be justified. Bigger is not always better – only where bigger can be shown to be better by reasons in addition to the modest cost benefits of ultra-class equipment. Truck over-loading may, to a moderate degree, increase productivity, but only at increased unit cost. / From a unit-cost perspective it is better to under-load than overload mining trucks. Where unit production cost is more important than absolute productivity, under-trucking is favoured compared with over-trucking loading equipment. Bunching of mining trucks manifests as a queuing effect – a loss of effective truck hours. To offset the queuing effect, required productivity needs to be adjusted to anticipate “bunching inefficiency”. The “basic number of trucks” delivered by deterministic estimating must provide for bunching inefficiency before application of simulation applications or stochastic analysis is used to determine the necessary number of trucks in the fleet. In difficult digging conditions it is more important to retain truck operating rhythm than to focus on achieving target payload by indiscriminately adding loader passes. Where trucks are waiting to load, operational tempo should be restored by sacrificing one or more passes. Trucks should preferably be loaded by not more than the nominal (modal) number plus one pass. The research has: • Identified and investigated attributes that affect the dispersion of truck payloads, bucket loads, bucket-cycle time, loading time and truck-cycle time. • The outcomes of the research indicate a need to correlate drilling and blasting quality control and truck payload dispersion. Further research can be expected to determine the interrelationship between accuracy of drilling and blasting attributes including accuracy of hole location and direction. • Preliminary investigations indicate a relationship between drill-and-blast attributes through blasting quality control to bucket design, dimensions and shape; also discharge characteristics that affect bucket cycle time that needs further research.
415

The effects of parallel versus sequential coordination methods on distributed group multiple critera decision-making outcomes : an empirical study with a web-based GDSS prototype

Cao, Patrick Pu, 1963- January 2003 (has links)
Abstract not available
416

Developing a GIS-Based Decision Support Tool For Evaluating Potential Wind Farm Sites

Xu, Xiao Mark January 2007 (has links)
In recent years, the popularity of wind energy has grown. It is starting to play a large role in generating renewable, clean energy around the world. In New Zealand, there is increasing recognition and awareness of global warming and the pollution caused by burning fossil fuels, as well as the increased difficulty of obtaining oil from foreign sources, and the fluctuating price of non-renewable energy products. This makes wind energy a very attractive alternative to keep New Zealand clean and green. There are many issues involved in wind farm development. These issues can be grouped into two categories - economic issues and environmental issues. Wind farm developers often use site selection process to minimise the impact of these issues. This thesis aims to develop GIS based models that provide effective decision support tool for evaluating, at a regional scale, potential wind farm locations. This thesis firstly identifies common issues involved in wind farm development. Then, by reviewing previous research on wind farm site selection, methods and models used by academic and corporate sector to solve issues are listed. Criteria for an effective decision support tool are also discussed. In this case, an effective decision support tool needs to be flexible, easy to implement and easy to use. More specifically, an effective decision support tool needs to provide users the ability to identify areas that are suitable for wind farm development based on different criteria. Having established the structure and criteria for a wind farm analysis model, a GIS based tool was implemented using AML code using a Boolean logic model approach. This method uses binary maps for the final analysis. There are a total of 3645 output maps produced based on different combination of criteria. These maps can be used to conduct sensitivity analysis. This research concludes that an effective GIS analysis tool can be developed for provide effective decision support for evaluating wind farm sites.
417

TAFE and award restructuring processes, a case study : development of skill standards and assessment criteria for the civil operating stream of the building and construction industry

Naylor, Margaret, n/a January 1991 (has links)
This thesis addresses the argument that TAFE as an organisation has not significantly changed its concept of its purpose and place in Australian society over the last hundred years. It concludes that Industry Award Restructuring may possibly achieve what two world wars, two depressions, one economic boom, international civil rights movements and technological change could not: TAFE may change substantially over the next decade and move from its self-concept as an education institution into an overt training role. Due to award restructuring in industry, new demands will be made on TAFE which cannot be resisted if TAFE is to maintain its position as the primary provider of vocational education/training. In the course of the research it was found that it is possible to carry out direct observation of an organisation or industry without significantly affecting the processes of the organisation. This may be achieved by finding a role which complements, supports or supplements the organisation's objectives, but in which there are no line responsibilities and thus little or no interference. Such a role appears to be that of writer of documents, which gives unlimited access to all parties and sources without influencing either policy or practice. The outputs from the writing tasks are of value to the target organisation, so that the researcher gives as well as takes, and could be described as being in a symbiotic relationship with the organisation. The skill standards and assessment criteria developed during the study are presented as outcomes of a symbiotic case study, and the success of the method is evaluated by comparing the outcomes with those of other Streams of the same industry, which have been working on similar document development tasks over the same time period using traditional methods.
418

委外承包商評估準則模式之建構 / Constructing anit outsourcer selection model for it outsouring projects

周明昌, Chou, Ming-Chang Unknown Date (has links)
本研究在於探討可能會影響企業選擇委外承包商時的評估準則之因素,然後藉由大樣本之問卷調查,確認與選擇委外承包商之評估準則相關的因素,並建立選擇委外承包商的評估準則建議模式。 本研究的研究對象為臺灣地區曾經將資訊系統予以委外的大型企業之資訊主管。問卷調查所要搜集的資料主要涵蓋四大部份,分別為企業選擇委外承包商的評估準則、組織特性、委外計劃特性與資訊系統特性。抽樣樣本數為900家,採用分層隨機抽樣的方式進行抽樣,分層的方式則按產業別予以分層,製造業抽取500家、服務業抽取300家、金融業100家全部抽取,計回收182份,回收率為20.22%,扣除無效問卷30份,共有152份有效問卷,樣本有效回收率為l6.8%。本研究僅留下對委外成效感到尚可與滿意的問卷來建構模式,刪掉委外成效不佳的問卷,主要是希望所建構的模式能專注於學習對委外成效感到尚可與滿意的資訊主管的決策特性。 藉由此建議模式,管理者僅需要輸入一些資料,如企業特性、委外計劃特性與資訊系統特性等,該模式便會建議管理者應考慮的評估準則群,與其中較重要的評估準則子群。使管理者在面臨並非每天發生的資訊系統委外承包商選擇時,能夠有一個快速的起步,降低因委外經驗不足或委外經驗不夠寬廣所產生的困擾,也使得其他管理者的各類資訊系統委外經驗得以有系統的傳承與分享。本研究之委外承包商評估準則建議模式已建構完成,並以Excel的檔案格式存於磁片,管理者可以藉由與模式的互動,而在短短的數秒鐘內便可獲得模式所提供的建議。
419

Evaluation of tartrate stabilisation technologies for wine industry.

Low, Lin Lin. January 2007 (has links)
In the Australian wine industry, cold stabilisation is a widely used industrial process to prevent tartrate instability in bottled wines. This process involves cooling the wine close to its freezing point for extended periods, thereby inducing tartrate precipitation. However, it has several important disadvantages. Consequently, alternative methods to cold stabilisation have been developed. This includes electrodialysis, nanofiltration and contact processes. In this study, current knowledge regarding performance and cost of cold stabilisation and alternative technologies for tartrate stabilisation is reviewed. Whilst there have been occasional cost comparisons between cold stabilisation and alternative technologies, existing data is not suitable for properly evaluating the relative economics of the different process options. Therefore, alternative technologies to cold stabilisation, including the Westfalia process, nanofiltration and electrodialysis were compared for both technical and economic performance. Berri Estates Winery was used as the basis for engineering calculations and conceptual cost estimates. This is the first time that such a comprehensive evaluation has been undertaken of a broad range of alternative technologies for tartrate stabilisation during wine production. Product loss was a key cost driver in differentiating tartrate stabilisation processes. Cold stabilisation was found to be the most economic treatment process irrespective of scale or winery size. The Westfalia process and nanofiltration were the next most cost effective options. Data for economic evaluation and environmental assessment were summarised in a survey form that was circulated to technical experts from Hardy Wine Company, the Australian Wine Research Institute (AWRI) and the University of Adelaide. The purpose of the survey was to obtain the experts’ opinions on the merits of the alternative technologies. The results of this survey were used for comparison between current cold stabilisation and alternative technologies, by performing multi-criteria decision analysis (MCDA). This represents an original application of MCDA techniques to decision making in the wine industry. The MCDA analysis identified a strong preference by experts for nanofiltration combined with centrifugation as an alternative to cold stabilisation. As a consequence, laboratory investigations and field testing of nanofiltration were conducted to obtain new and practical information which was not presently available and relevant to understanding and implementing this process for tartrate stabilisation of wine. The laboratory experiments were performed with a range of membranes and tartrate unstable wines (i.e. Semillon, Colombard and Shiraz) using a purpose-designed laboratory-scale continuously-stirred batch-test membrane cell. The results showed that a range of commercial nanofiltration membranes with a nominal molecular weight cut-off (MWCO) between 200 and 500 Daltons (Da) were able to achieve tartrate stabilisation of all wines tested. This was achieved at moderate pressures less than 20 bar with a recovery of at least 50 %. It was also observed that seeding of wine following nanofiltration might reduce the holding time required to achieve stability and also enable reductions in the recovery rate to values of less than 50 %. The field testing was performed at Berri Estates Winery in the Riverland region of South Australia. The testing was performed using an existing commercial membrane system. This membrane system was already used for juice/wine concentration. The nanofiltration membranes had a nominal MWCO of 300 Da. The testing was conducted on Colombard and Shiraz wines. The field tests confirmed that nanofiltration could successfully tartrate stabilise Colombard and Shiraz wines at recoveries of 50 %; without seeding; within relatively short holding periods of less than four hours; and at flux rates between 5 and 10 L/m²/h. Crystallisation kinetics were also studied. At low recovery, the crystallisation was initially controlled by diffusion step, then surface integration. However, at high recovery, the crystallisation was controlled solely by surface integration. Sensory testing (by duo-trio difference tests) produced adverse sensory outcomes when compared with treatment of the same wines by cold stabilisation. Unfortunately, it could not be established whether this problem was inherent to the process or arose from unrelated factors. Setting aside the adverse sensory result, this is the first time that technical feasibility of nanofiltration for tartrate stabilisation has been successfully demonstrated. Further field testing and sensory evaluation of nano-filtered wines should be carried out to verify the effect of nanofiltration on wines. If the process is successful and favourable, the process design for implementation of a production scale nanofiltration for tartrate stabilisation should then be optimised. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292872 / Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering, 2007.
420

Evaluation of tartrate stabilisation technologies for wine industry.

Low, Lin Lin. January 2007 (has links)
In the Australian wine industry, cold stabilisation is a widely used industrial process to prevent tartrate instability in bottled wines. This process involves cooling the wine close to its freezing point for extended periods, thereby inducing tartrate precipitation. However, it has several important disadvantages. Consequently, alternative methods to cold stabilisation have been developed. This includes electrodialysis, nanofiltration and contact processes. In this study, current knowledge regarding performance and cost of cold stabilisation and alternative technologies for tartrate stabilisation is reviewed. Whilst there have been occasional cost comparisons between cold stabilisation and alternative technologies, existing data is not suitable for properly evaluating the relative economics of the different process options. Therefore, alternative technologies to cold stabilisation, including the Westfalia process, nanofiltration and electrodialysis were compared for both technical and economic performance. Berri Estates Winery was used as the basis for engineering calculations and conceptual cost estimates. This is the first time that such a comprehensive evaluation has been undertaken of a broad range of alternative technologies for tartrate stabilisation during wine production. Product loss was a key cost driver in differentiating tartrate stabilisation processes. Cold stabilisation was found to be the most economic treatment process irrespective of scale or winery size. The Westfalia process and nanofiltration were the next most cost effective options. Data for economic evaluation and environmental assessment were summarised in a survey form that was circulated to technical experts from Hardy Wine Company, the Australian Wine Research Institute (AWRI) and the University of Adelaide. The purpose of the survey was to obtain the experts’ opinions on the merits of the alternative technologies. The results of this survey were used for comparison between current cold stabilisation and alternative technologies, by performing multi-criteria decision analysis (MCDA). This represents an original application of MCDA techniques to decision making in the wine industry. The MCDA analysis identified a strong preference by experts for nanofiltration combined with centrifugation as an alternative to cold stabilisation. As a consequence, laboratory investigations and field testing of nanofiltration were conducted to obtain new and practical information which was not presently available and relevant to understanding and implementing this process for tartrate stabilisation of wine. The laboratory experiments were performed with a range of membranes and tartrate unstable wines (i.e. Semillon, Colombard and Shiraz) using a purpose-designed laboratory-scale continuously-stirred batch-test membrane cell. The results showed that a range of commercial nanofiltration membranes with a nominal molecular weight cut-off (MWCO) between 200 and 500 Daltons (Da) were able to achieve tartrate stabilisation of all wines tested. This was achieved at moderate pressures less than 20 bar with a recovery of at least 50 %. It was also observed that seeding of wine following nanofiltration might reduce the holding time required to achieve stability and also enable reductions in the recovery rate to values of less than 50 %. The field testing was performed at Berri Estates Winery in the Riverland region of South Australia. The testing was performed using an existing commercial membrane system. This membrane system was already used for juice/wine concentration. The nanofiltration membranes had a nominal MWCO of 300 Da. The testing was conducted on Colombard and Shiraz wines. The field tests confirmed that nanofiltration could successfully tartrate stabilise Colombard and Shiraz wines at recoveries of 50 %; without seeding; within relatively short holding periods of less than four hours; and at flux rates between 5 and 10 L/m²/h. Crystallisation kinetics were also studied. At low recovery, the crystallisation was initially controlled by diffusion step, then surface integration. However, at high recovery, the crystallisation was controlled solely by surface integration. Sensory testing (by duo-trio difference tests) produced adverse sensory outcomes when compared with treatment of the same wines by cold stabilisation. Unfortunately, it could not be established whether this problem was inherent to the process or arose from unrelated factors. Setting aside the adverse sensory result, this is the first time that technical feasibility of nanofiltration for tartrate stabilisation has been successfully demonstrated. Further field testing and sensory evaluation of nano-filtered wines should be carried out to verify the effect of nanofiltration on wines. If the process is successful and favourable, the process design for implementation of a production scale nanofiltration for tartrate stabilisation should then be optimised. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292872 / Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering, 2007.

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