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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.
191

行政效率測量標準與方法之研究

吳定, Wu, Ding Unknown Date (has links)
本論文名為「行政效率測量標準與方法之研究」,除緒言外,共分七章。全文約十二萬字。 在「緒言」中,略述個人研究本文的動機與意旨,以及研究的重點與範圍。第一章「行政效率的概念」,首先闡述行政效率的性質、意義、辨正等。次論行政效率測量的意義,目的及其所遭遇的困難期澄清行政效率的基本概念,以利行政效率測量標準與方法的探討。第二章「行政效率測量標準」,就行政效率的性質,分成三個層次予以討論; 其一為機械性效率,凡行政機關工作屬於機械性者,適用機械性效率測量標準。筆者從各種角度提出七項測量標準,以供參考。其二為組織性效率,凡行政機關組織、人員、管理及運作情況的效率均屬之,適用組織性效率測量標準。筆者亦提出七項測量標準討論。其三為社會性效率,著重行政活動對社會所具的功能與價值等,適用社會性效率的測量標準。筆者提出討論的測量標準有三項。第三章為「行政效率測量方法」,採用統計分析方法與數理公式,論述行政效率測量的方法與技術。其中有的屬於理論性探討,有的則為現行測量辦法,筆者就此些辦法加以論列分析,並舉述實例,俾明其應用。第四章「我國行政效率測量的實施」,略論人事行政局與台北市政府的實施情形,並檢討其利弊,提出建議事項,以供參考改進。第五章「行政效率的測量人員」,鑒於「徒法不足以自行」,「為政在人」,故本章敘述如何遴任及訓練行政效率測量人員。期以人員的優點彌補制度的闕漏。第六章為「我國行政效率測量的展望」,闡明我國目前行政效率測量制度未臻完善,應從速謀求研究改進,加強實施工作簡化,計劃評核術與目標管理等新近管理技術,擬訂妥善的測量標準與方法。最後一章「結論」,綜合全文的研究心得提出報告,強調檢討現行制度缺點,力求改進,健全存政效率測量制度,增進行政效率,實現行政革新。本文研究方式,主要為理論性探討,並佐以若干實例,以求理論與實際相配合,研究範圍包括行政機關的組織、制度、人員及運作等,以求普遍討論效率測量標準與方法。筆者會去信美國當代名行政學者西蒙(Herbert A. Simon)教授,請教有關行政效率測量問題。西蒙教授謙虛表示,最近十幾年來,他的研究工作很少觸及行政效率、測量標準與方法。其主要觀點幾乎已盡括於「行政學士」(Public Adiministration 1956)一書中。但他指出美國這方面的研究趨向於「成本利益分析」(Cost-Benefit Analysis) 。西蒙教授並贈送筆者一書,名為「經由系統分析增進政府效率」(Efficiency in Government through Systems Analysis. by Roland N. Mckean, 1958) 其內容主要敘述利用成本利益分析以抉擇行政活動計劃,但與效率測量亦具有相當密切的關係,故本文會約略論及。
192

Computer-Aided Manufacturing Planning (CAMP)of Mass Customization for Non-rotational Part Production

Yao, Suqin 16 December 2003 (has links)
"This research is aimed at studying the key technologies of Computer-Aided Manufacturing Planning (CAMP) of mass customization for non-rotational part production. The main goal of the CAMP is to rapidly generate manufacturing plans by using of the best-of-practice (BOP) provided by specific companies. A systematic information modeling hierarchy is proposed to facilitate changes in manufacturing plans according to changes in part design. The Object-oriented Systems Analysis (OSA) approach is used to represent information relationships and associativities in the CAMP. A feature-based part information model, a process model, a setup planning model, and manufacturing resource capability models are established. A three-level decision-making mechanism is proposed for the CAMP. At the feature- level, combined features are defined based on part families, and a process model is proposed to describe the information associativities between features and their manufacturing strategies, which include customized cutters and toolpaths. At the part level, graph-based setup planning is carried out by tolerance analysis and manufacturing resource capability analysis. At the machine level, multi-part fixtures are utilized to pursue high productivity. Cycle time is used to evaluate manufacturing plans. Computer software for the CAMP has been developed and integrated with CAD package Unigraphs. The BOP of part families is stored in XML format, which has good extendibility and can be read and edited by standard browsers."
193

Green consumption energy use and carbon dioxide emission

Alfredsson, Eva January 2002 (has links)
The aim of this thesis is to explore the quantitative potential to reduce energy requirements and CO2 emissions through changed patterns of consumption, given unchanged levels of consumption expenditure. The thesis question is analysed using a systems analysis approach which in this case means that life cycle assessment data on energy requirements and CO2 emissions related to household consumption are combined with a financial and behavioural analysis to make sure that the budget constraint is kept and that both the first and second order effects of adopting a green consumption pattern are analysed. The budget constraints are kept using a general linear model. By using marginal propensities to spend to direct the reallocation of saved or deficit money calculated utility is maintained as far as possible. Further, investigations explore the impact of individual household demographic characteristics and geographic context on household consumption patterns, energy requirements and CO2 emissions. The key result of this thesis is that changed household behaviour, choosing “green“ products and energy efficient technology will not make a big difference. What can be achieved in the short time perspective by adopting an almost completely green consumption pattern and energy efficient technology is a reduction of energy requirements by around 8% and CO2 emissions by around 13%. With a longer time perspective and further technological change that provides additional possibilities to move consumption patterns in a greener direction, the effect on energy requirements and CO2 emissions is still fairly small. By 2020, the potential to reduce energy requirements is around 13% and CO2 emissions around 25%. In the most extreme scenario (2050), the scope for reducing energy requirements is 17% and for CO2 emissions 30%. All these reductions will be outpaced by growth in income almost as soon as they are implemented. Of policy relevance the results reveal that very limited impact can be expected by a policy relying on greener consumption patterns, whether adopted voluntarily or as a result of incentives such as tax changes. Such a policy cannot achieve more than a small and temporary reduction to growth in energy requirements and CO2 emissions. It is also shown that, prescribing specific consumption patterns as a means of reducing energy requirements and CO2 emissions has to be done with care. This is illustrated by one of the experiments in which adopting a partly green consumption pattern, a green diet, in fact increased total energy requirements and CO2 emissions. This, and the results of all the other experiments show the importance of applying a systems approach. It demonstrates that life cycle data alone are irrelevant for assessing the total effects of adopting green consumption patterns. Further research on the potential to reduce energy requirements and CO2 emissions thus primarily needs to better capture system wide effects rather than to improve on, and fine tune the measurement of the energy requirements and CO2 emissions related to individual products.
194

Environmental System Analysis of Waste Management : Experiences from Applications of the ORWARE Model

Björklund, Anna January 2000 (has links)
Waste management has gone through a history of shiftingproblems, demands, and strategies over the years. In contrastto the long prevailing view that the problem could be solved byhiding or moving it, waste is now viewed as a problem rangingfrom local to global concern, and as being an integral part ofseveral sectors in society. Decisive for this view has beensociety’s increasing complexity and thus the increasingcomplexity of waste, together with a general development ofenvironmental consciousness, moving from local focus on pointemission sources, to regional and global issues of more complexnature. This thesis is about the development and application orware;a model for computer aided environmental systems analysis ofmunicipal waste management. Its origin is the hypothesis thatwidened perspectives are needed in waste managementdecision-making to avoid severe sub-optimisation ofenvironmental performance. With a strong foundation in lifecycle assessment (LCA), orware aims to cover the environmentalimpacts over the entire life cycle of waste management. It alsoperforms substance flow analysis (SFA) calculations at a ratherdetailed level of the system. Applying orware has confirmed the importance of applyingsystems perspective and of taking into account site specificdifferences in analysis and planning of waste manage-ment,rather than relying on overly simplified solutions. Somefindings can be general-ised and used as guidelines to reduceenvironmental impact of waste management. Recovery of materialand energy resources from waste generally leads to netreductions in energy use and environmental impact, because ofthe savings this brings about in other sectors. Waste treatmentwith low rate of energy and materials recovery should thereforebe avoided. The exact choice of technology however depends onwhat products can be recovered andhow they are used. Despite the complexity of the model and a certain degree ofuser unfriendliness, involved stakeholders have expressed thevalue of participating in orware case studies. It providesimproved decision-basis, but also wider understanding of thecomplexity of waste management and of environmental issues ingeneral. The thesis also contains a first suggestion of a frameworkto handle uncertainty in orware, based on a review of types ofuncertainty in LCA and tools to handle it. / QC 20100413
195

A Markovian state-space framework for integrating flexibility into space system design decisions

Lafleur, Jarret Marshall 16 December 2011 (has links)
The past decades have seen the state of the art in aerospace system design progress from a scope of simple optimization to one including robustness, with the objective of permitting a single system to perform well even in off-nominal future environments. Integrating flexibility, or the capability to easily modify a system after it has been fielded in response to changing environments, into system design represents a further step forward. One challenge in accomplishing this rests in that the decision-maker must consider not only the present system design decision, but also sequential future design and operation decisions. Despite extensive interest in the topic, the state of the art in designing flexibility into aerospace systems, and particularly space systems, tends to be limited to analyses that are qualitative, deterministic, single-objective, and/or limited to consider a single future time period. To address these gaps, this thesis develops a stochastic, multi-objective, and multi-period framework for integrating flexibility into space system design decisions. Central to the framework are five steps. First, system configuration options are identified and costs of switching from one configuration to another are compiled into a cost transition matrix. Second, probabilities that demand on the system will transition from one mission to another are compiled into a mission demand Markov chain. Third, one performance matrix for each design objective is populated to describe how well the identified system configurations perform in each of the identified mission demand environments. The fourth step employs multi-period decision analysis techniques, including Markov decision processes (MDPs) from the field of operations research, to find efficient paths and policies a decision-maker may follow. The final step examines the implications of these paths and policies for the primary goal of informing initial system selection. Overall, this thesis unifies state-centric concepts of flexibility from economics and engineering literature with sequential decision-making techniques from operations research. The end objective of this thesis' framework and its supporting analytic and computational tools is to enable selection of the next-generation space systems today, tailored to decision-maker budget and performance preferences, that will be best able to adapt and perform in a future of changing environments and requirements. Following extensive theoretical development, the framework and its steps are applied to space system planning problems of (1) DARPA-motivated multiple- or distributed-payload satellite selection and (2) NASA human space exploration architecture selection.
196

Collective Utility: A Systems Approach for the Utilization of Water Resources

Dupnick, Edwin, Duckstein, Lucien 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / In the semiarid southwestern U.S. where competition for water is fierce between competing users, no regional agency controls water allocation, and as a result, much court litigation ensues. This paper attempts to develop a model for optimal allocation of water resources and to apply the model to a specific case study. In November 1969, the largest farming interest in the Sahuarita-continental area near Tucson filed a court suit seeking first to reduce the amount of groundwater used by 4 nearby copper mines, and then to allocate the water more evenly among various interests in the area. The farming interest maintained that the mines' drawdown on the groundwater table would soon deplete the supply to the point where agriculture would become impossible. The model utilizes the concept of collective utility which postulates the existence of an economic decision maker (edp). To get around the problem of determination of net revenue functions, the theory compares the relative desirability of neighboring economic states. The edp has the power to impose groundwater-use taxes in such a way as to maximize overall growth of collective utility in the Sahuarita-continental area, taking into account the externalities of the resource consumption. The mathematical analysis is presented in detail.
197

Uma estratégia de interação na Web para a análise de sistemas elétricos de potência

Tamashiro, Márcio Augusto 14 October 2016 (has links)
CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Atualmente, muitos trabalhos técnicos e científicos importantes só são possíveis com o auxílio de computadores e de programas específicos. Na Engenharia Elétrica esses recursos são utilizados em estudos estáticos e dinâmicos de sistemas elétricos de potência, os quais dão suporte, por exemplo, ao planejamento e a operação da rede elétrica realizados pelas empresas do setor. Em função dessa importância é grande a quantidade de programas disponíveis, comerciais ou não. As aplicações comerciais são conhecidas por serem computacionalmente eficientes, bem como pela quantidade de recursos oferecidos, mas apesar disso, não são adequadas para fins educacionais ou para a realização de pesquisas. Um dos principais motivos apontados é porque o código fonte não é fornecido, e assim não podem ser estudados ou adaptados conforme a necessidade. Por isso muitos usuários principalmente do meio acadêmico preferem criar suas próprias aplicações, sendo a maioria delas desenvolvidas no MATLAB ou escritas nas linguagens de programação FORTRAN e C++. Esses programas são disponibilizados como aplicações desktop destinadas geralmente a somente um tipo de estudo e com uma interface pouco amigável. Entretanto, existem algumas opções com características mais atrativas como a existência de uma interface gráfica com o usuário, e número de recursos computacionais próximos àqueles encontrados nas aplicações comercias. Na literatura há ainda propostas de aplicações web cuja principal vantagem é o acesso remoto e simultâneo por qualquer computador. No geral, as aplicações existentes não disponibilizam recursos de colaboração em tempo real, e não permitem a interoperabilidade com outras aplicações. Nesse contexto, esta tese focou na investigação da implementação de uma aplicação web para a análise de sistemas elétricos, explorando esses dois aspectos supracitados. Para isso alguns programas similares, sem fins comerciais e com código fonte disponível, foram investigados. E também foram selecionadas e apresentadas as ferramentas computacionais necessárias ao desenvolvimento da aplicação. As investigações e as implementações computacionais realizadas, bem como os resultados obtidos são devidamente apresentados e analisados ao final deste trabalho. / Currently, many important technical and scientific works are only possible with the aid of computers and specific programs. In Electrical Engineering, these resources are both used in static and dynamic studies of electric power systems, which give support, for example, to the planning, and operation of the grid performed by companies in the sector. Because of this, there is a large number of commercial or non-commercial programs available. Commercial applications are known to be computationally efficient as well as the amount of offered resources; nevertheless, they are not suitable for educational purposes or for conducting research. One of the main reasons pointed out is because they are not open source, and thus they cannot be studied or adapted as needed. Thus, many users, quite often in academia, prefer to create their own applications, most of them written in MATLAB, FORTRAN and C ++ programming languages. These programs are provided as desktop applications usually designed to only one type of study and without user-friendly interface. However, there are a few options with more attractive features such as the existence of a graphical user interface, and number of computational resources close to those found in commercial applications. There are also proposals in the literature for web applications whose main advantage is the remote and simultaneous access by any computer. Generally, the existing applications do not make available real-time collaboration features, and no interoperability with other applications. In this context, this thesis focused on the research of the implementation of a web application for analysis of electrical power systems, exploring these two aspects above mentioned. For that, some similar non-commercial programs and open-source were deeply investigated. In addition, the computational tools necessary to develop the application were selected and presented. The investigations and computational implementation performed here, as well as the results are properly presented and analyzed at the end of this work. / Tese (Doutorado)
198

A systems approach to biogasplanning in Stockholm, Sweden

Österlin, Calle January 2012 (has links)
The Swedish capital Stockholm is at the forefront of biogas gas use, especially when it comesto biogas used for vehicle gas. This technology has the potential of being a fuel with veryhigh environmental performance, but in order to realize the full potential publicenvironmental management must be optimized. Environmental objectives are anenvironmental management is one tool that is used to strive for the desired development. Theaim of this study is to explain the dynamics within the biogas system in Stockholm, with aparticular emphasis on which factors that affects the amount of biogas available for vehiclegas upgrading on the market in Stockholm. The study has been conducted using modelingsessions with key stakeholders involved in the biogas system. The study concludes that theformulation of environmental objectives has a profound impact on how the variousstakeholders act, and thus how the system behaves. The trade off of how much fossil naturalgas that can be mixed into the renewable biogas based vehicle gas is at the very pinnacle ofcomplex matter. A conclusion that is of vital importance for the local planning process andwhen the experiences of Stockholm’s environmental planning are communicated out to therest of the world.
199

The identification of environmentally sound technologies for healthcare waste management in Lesotho

Ramabitsa-Siimane, Ts’aletseng M 11 May 2006 (has links)
Waste resulting from healthcare activities is hazardous due to its potential risk of infection to healthcare workers, waste workers and the public. Many tools and approaches have been applied in waste management in developed countries, but are not suitable for application in developing countries due to their complexity and extensive data and resource requirements. WasteOpt was therefore developed and applied as an appropriate decision-making tool in the developing country context. WasteOpt comprises of the Analytical Hierarchy Process (AHP), costing and Life cycle management (LCM). The purpose of this study was to identify environmentally sound technologies (ESTs) that minimise the risk of infection by healthcare waste (HCW) in rural clinics. Rural clinics were selected because apart from financial constraints, they are challenged by the lack of procedure, infrastructure and technologies to develop reasonable waste management plans that can be implemented within a practicable time frame. WasteOpt was applied to aid in identifying ESTs in relation to the infection risks and costs of the technologies. Experts in waste management in Lesotho were involved in a workshop for the ranking of technologies. The overall weighting values of the rankings were converted to risk factors for individual options and for alternatives (combination of options). Risk factors were classified as low, medium and high risk. The technologies within a single class were differentiated by analysing the cost of acquiring and running the technology to qualify as ESTs. The ESTs identified for Lesotho are Engineered containers, Refrigerated engineered facility, engineered wheeled transport, detailed procedures, multi chamber incinerator, engineered pit and landfill. Ten (10) clinics in Lesotho were also assessed as case studies using the WHO RAT. The RAT was first modified to include questions on financial management at the clinics. The calculated risk factors were applied to the case studies to assess the risk under which healthcare workers operate in those clinics. The additive minimum risk for the overall life cycle of waste was 4.0 (excluding central treatment and disposal). The clinic workers were found to be at a risk of between 1.1 x 10-4 and 7.8 x 10-5, which proves that rural clinics in Lesotho are still using inappropriate technologies. In terms of financing for waste management, public clinics were found to have little decision-making powers over funds and had less accountability measures. CHAL clinics which are managed by churches in Lesotho had more control of funds and exhibit more accountability. All clinics had no targets for saving funds from waste management activities. WasteOpt can be applied as a decision-making tool for HCW in Lesotho since it overcomes the barriers that inhibit environmentally sound management of HCW in developing countries. In conclusion: WasteOpt can be applied as a decision-making tool for different types of waste by replacing HCW options with respective ones and designing a relevant questionnaire for qualitative data capture. WasteOpt can then be applied in a developing country to aid sustainable waste management decision-making. Informed decision-making helps resource poor managers to select cost-effective but low-risk options, which will be sustainable in the future. / Dissertation (MSc (Environmental Technology))--University of Pretoria, 2007. / Chemical Engineering / unrestricted
200

Future of asynchronous transfer mode networking

Hachfi, Fakhreddine Mohamed 01 January 2004 (has links)
The growth of Asynchronous Transfer Mode (ATM) was considered to be the ideal carrier of the high bandwidth applications like video on demand and multimedia e-learning. ATM emerged commercially in the beginning of the 1990's. It was designed to provide a different quality of service at a speed up 100 Gbps for both real time and non real time application. The turn of the 90's saw a variety of technologies being developed. This project analyzes these technologies, compares them to the Asynchronous Transfer Mode and assesses the future of ATM.

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