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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.
1

Decision Aid for Planning Local Energy Systems : Application of Multi-Criteria Decision Analysis

Catrinu, Maria January 2006 (has links)
<p>Planning is what sustains an energy system. It is a process of analysis and ongoing decision making about what resources and energy technologies to use when supplying energy to society. This research focuses on integrated energy systems, i.e. systems that are comprised of several energy carriers – electricity, gas, hot water - and energy distribution networks. The planning of these kinds of systems is a complex process, influenced by many factors, among which the most important are the availability of energy resources and the competition between different energy carriers in satisfying energy demand. During the last 10-20 years significant changes have taken place on the world energy scene, which have important implications for energy planning. Two main factors have triggered these changes. The first factor is the immediate need to address environmental changes or more generally, to take measures that are sustainable in the long run. Sustainability can be defined in many ways and in relation to different issues such as economic and ecologic development, reduction of greenhouse gases, responsible use of natural resources, social equity, etc. In recent years, an increased awareness of these issues has been observed at all levels of the society. The second factor is the deregulation of national energy sectors in more than 50 countries. This process brought changes in the ownership of different parts of the formerly integrated energy systems. New business opportunities were created in power generation, wholesale power/gas trading and energy retailing, while the energy infrastructures remained state owned or/and under regulatory control. The newly created energy markets (many of them international) have attracted both new players (power, oil and gas companies and financial institutions) together with the old ones (integrated utilities). In parallel with this vertical separation of national energy sectors, recent studies have shown a tendency for horizontal integration at the regional/company level. For instance, in order to reduce their overall business risk, companies prefer to participate in several segments of the energy value chain (in both regulated and non-regulated activities), and often across more than one fuel commodity, such as gas and electricity or district heating. In this context, the competition between different energy carriers in satisfying the end-use energy demand became obvious in economic as well as in technological and environmental terms. Traditionally, in integrated planning, this competition did not play a big role, since the same state entity made decisions at both national and regional levels. However, in the post-deregulation era it is no longer obvious who the planner is. In many cases, planning decision at local levels involve at least three main interest groups: energy companies (and/or other investors), the state and the local community. This thesis is motivated by the need to help planners to cope with the changes in concepts and values concerning the planning of local energy supply systems. This thesis has two aims. The first aim is to improve the understanding of what planning of local systems implies and how such a process can be structured. The second aim is to contribute to the development of decision support methodologies and tools that can cope with the needs in planning. For this purpose, the use of energy modelling and Multi- Criteria Decision Analysis has been studied.</p>
2

Decision Aid for Planning Local Energy Systems : Application of Multi-Criteria Decision Analysis

Catrinu, Maria January 2006 (has links)
Planning is what sustains an energy system. It is a process of analysis and ongoing decision making about what resources and energy technologies to use when supplying energy to society. This research focuses on integrated energy systems, i.e. systems that are comprised of several energy carriers – electricity, gas, hot water - and energy distribution networks. The planning of these kinds of systems is a complex process, influenced by many factors, among which the most important are the availability of energy resources and the competition between different energy carriers in satisfying energy demand. During the last 10-20 years significant changes have taken place on the world energy scene, which have important implications for energy planning. Two main factors have triggered these changes. The first factor is the immediate need to address environmental changes or more generally, to take measures that are sustainable in the long run. Sustainability can be defined in many ways and in relation to different issues such as economic and ecologic development, reduction of greenhouse gases, responsible use of natural resources, social equity, etc. In recent years, an increased awareness of these issues has been observed at all levels of the society. The second factor is the deregulation of national energy sectors in more than 50 countries. This process brought changes in the ownership of different parts of the formerly integrated energy systems. New business opportunities were created in power generation, wholesale power/gas trading and energy retailing, while the energy infrastructures remained state owned or/and under regulatory control. The newly created energy markets (many of them international) have attracted both new players (power, oil and gas companies and financial institutions) together with the old ones (integrated utilities). In parallel with this vertical separation of national energy sectors, recent studies have shown a tendency for horizontal integration at the regional/company level. For instance, in order to reduce their overall business risk, companies prefer to participate in several segments of the energy value chain (in both regulated and non-regulated activities), and often across more than one fuel commodity, such as gas and electricity or district heating. In this context, the competition between different energy carriers in satisfying the end-use energy demand became obvious in economic as well as in technological and environmental terms. Traditionally, in integrated planning, this competition did not play a big role, since the same state entity made decisions at both national and regional levels. However, in the post-deregulation era it is no longer obvious who the planner is. In many cases, planning decision at local levels involve at least three main interest groups: energy companies (and/or other investors), the state and the local community. This thesis is motivated by the need to help planners to cope with the changes in concepts and values concerning the planning of local energy supply systems. This thesis has two aims. The first aim is to improve the understanding of what planning of local systems implies and how such a process can be structured. The second aim is to contribute to the development of decision support methodologies and tools that can cope with the needs in planning. For this purpose, the use of energy modelling and Multi- Criteria Decision Analysis has been studied.
3

A multi criteria decision making method for selection an incubator

Chien, Shien-Shun 02 July 2004 (has links)
Abstract Small and medium enterprises (SMEs) were one of the major contributors to the economic miracle of Taiwan. There are over a million SMEs, which comprise 97.7% of all Taiwanese enterprises, However, SMEs faced with high risks of failure, especially at their entrepreneurship stages, due to their lack of expertise and abilities in technologies developments, together with their disadvantages in economy scale, market, capital and business connections. Thus more than 60 incubators were founded by Taiwan Government in past seven years to help SMEs entrepreneur cope with the above threaten. These incubators vary in factors such as capabilities, facility, and resources. Therefore, the selection of an appropriate incubator is a critical issue for an SME entrepreneur. This research identifies a set of evaluating criteria within five categories: facility, technical and human resource, business administrative, knowledge source, and organization infrastructure based on extensive literature review and interview with industry experts. ELECTRE I, a multiple criteria decision making method is applied to evaluate incubators. The results provide an efficient and effective method for selecting an appropriate incubator for SME entrepreneur.
4

A MCDM Method for Selecting an ERP Consultant Company and Consultant

Wang, Jyun-Yuan 03 July 2007 (has links)
ERP¡]Enterprise Resource Planning¡^comes from manufacturing industry at first. When the times develope, it hasn¡¦t the only patent in manufacturing industry. It changes the basic IS for all kinds of industries.In the past, the related topics for the researches of the the academic circle surrounded with the topics of ERP selecting and CSF. There are very fewer related researches for how to understand and how to select ERP consultant and Consultant Company.Because the academic and the industry circle recently understand the importance of consultant, consultant for ERP implementing is the success and failure role. Base on these reasons, those cause this research to discuss the topic of ERP consultant and Consultant Company. The purpose of this research is arranging and analysising the crieteria of selecting consultant and Consutant Company by collecting records¡Bexpert interviews and questionnaire. The research uses case studey to help for the case enterprise to select the most suitable ERP consultant by ELECTRE I and provides the rational decision structure and basis for the companies that want to implement ERP. At last , the case has selected JDE from the three consultant companies of Oracle¡BJDE and Proyoung. The result of this research mainly provides feasibility evaluation model. When company considers which consultant and Consultant Company to select, he can refer this crieteria and importance from this research. The company also finds the most suitable Consultant Company by using the methods and procedures from this research.
5

The Selection of e-Learning System:A Multi-criteria Decision Making Approach

Shih, I-Hsiung 23 June 2002 (has links)
As e-Learning has become an important trend for the training system of modern enterprises, there are many kinds of e-Learning system offered by different consulting companies with different specialties in Taiwan. To construct the best system, the enterprise must first find the real application in order to choose the optimum. The study, based on the purposes of enterprise requirement, tried to develop the methodology by using Multi-criteria Decision Making to help managers, the decision makers to evaluate an appropriate e-Learning project with a successful example of one famous ¡§steel corporation¡¨ in their evaluation by this method. From our study, the foresight in planning e-Learning system with prudent evaluation by taking the enterprise¡¦s present situation, his real needs and the evaluation model of decision making into account can avoid the prejudice of decision makers and the excessive propaganda of consulting company which might result in an inapplicable project. To the very enterprise that tries to construct his e-Learning System effectively, the methodology of Multi-criteria Decision Making provides the sequence of system selection and references for evaluation of system construction.
6

A MCDM Method for Selecting an ERP System

Tai, Wei-Chun 12 July 2002 (has links)
In this e-commerce era, Enterprise Resource Planning (ERP) has been viewed as the entering cost for conducting the business and establishing contact with others. ERP system is very expensive and enormous complex package software, and applies the best business practice with partial adjustment and integration to suit for the operation of different enterprises. But due to the characteristics of high investement, high complexity and high risk of failure of ERP systems, misfits have been one of important issues for the implementation of ERP systems. Therefore, the selection of an appropriate ERP system has become the key factor leading to the eventual success of an ERP system implementation. And we select an appropriate ERP system by studing a case that uses ELECTRE I as evaluating tool. This paper first identifies a set of evaluating criteria based on the extensive literature review and the considerat5ion of the environment and characteristics of ERP systems. Once the list was generated, an iterative process of personal interview with the consultant, suppliers, users and managers was conducted to modify the evaluating criteria in order to insure the integrity of it. The result of this study is not only can contribute to the understanding of the functionalities of an ERP system, but also can provide a practical guideline for the selection of an ERP system.
7

Multi-criteria decision aiding model for the evaluation of agricultural countermeasures after an accidental release of radionuclides to the environment

Turcanu, Catrinel O 31 October 2007 (has links)
Multi-criteria decision aid has emerged from the operational research field as the answer given to a couple of important questions encountered in complex decisions problems. Firstly, as decision aiding tools, such methods do not replace the decision maker with a mathematical model, but support him to construct his solution by describing and evaluating his options. Secondly, instead of using a unique criterion capturing all aspects of the problem, in the multi-criteria decision aid methods one seeks to build multiple criteria, representing several points of view. This work explores the application of multi-criteria decision aid methods for optimising food chain countermeasure strategies after a radioactive release to the environment. The core of the thesis is dedicated to formulating general lines for the development of a multi-criteria decision aid model. This includes the definition of potential actions, construction of evaluation criteria and preference modelling and is essentially based on the results of a stakeholders’ process. The work is centred on the management of contaminated milk in order to provide a concrete focus and because of its importance as an ingestion pathway in short term after an accident. Among other issues, the public acceptance of milk countermeasures as a key evaluation criterion is analysed in detail. A comparison of acceptance based on stochastic dominance is proposed and, based on that, a countermeasures’ acceptance ranking is deduced. In order to assess “global preferences” taking into account all the evaluation criteria, an ordinal method is chosen. This method allows expressing the relative importance of criteria in a qualitative way instead of using, for instance, numerical weights. Some algorithms that can be used for robustness analysis are also proposed. This type of analysis is an alternative to sensitivity analysis in what concerns data uncertainty and imprecision and seeks to determine how and if a model result or conclusion obtained for a specific instance of a model’s parameters holds over the entire domain of acceptable values for these parameters. The integrated multi-criteria decision aid approach proposed makes use of outranking and interactive methodologies and is implemented and tested through a number of case studies and prototype tools.
8

Design and testing of a novel human-powered generator device as a backup solution to power Cranfield´s Nano-Membrane Toilet

Perez Lopez, Eloy 04 1900 (has links)
In today’s world there are 2.6 billion people that lack basic sanitation (37% of world inhabitants). In August of 2012, Cranfield University was awarded by the Bill & Melinda Gates Foundation with $810,000 to produce a prototype of the Cranfield’s innovative Nano-membrane Toilet (NMT). Finally, the prototype is going to be exhibited at the “Reinvent the Toilet Fair” during 21st and 22nd of March 2014 in the Taj Palace Hotel, New Delhi (India). Cranfield’s NMT demands electricity for its daily performance. Nevertheless, it is targeted to off-grid communities. Consequently, a human-powered generator (HPG) was selected as a backup solution. The current MSc by Research aimed to design and test of a prototype of the aforesaid HPG. Moreover, to promote its usage, a portable power supply unit is designed to store energy and power small-loads like charging mobile phones and electric lighting. To select the most suitable design for our case study, a methodology using the Technique for Order of Preference by Similarity to the Ideal Solution has been developed. As a result the plugged-in bike HPG alternative was selected. Next, prototypes of this generator and the portable power supply unit were developed, tested and shipped for display. While testing of the plugged-in generator and portable power supply unit, 26 Watt-hours (Wh) were harvested over 15 minutes, with its corresponding average charging power of 105 Watts. Nevertheless, the present study concludes 96 Wh as a more accurate energy level to be harvested during one hour of pedalling. Considering 96 Wh of energy, a round-trip battery efficiency of 70% (lead-acid), and a NMT’s demand of 283 Wh; a 10 people household needs to pedal the HPG over 4 hours and 20 minutes. Nevertheless, if considering an 85% inverter efficiency, 57.12 Wh are available to fully charge one mobile phone (5.6 Wh) and provide 4.5 hours of room and desk lighting (11 Watts bulb).
9

Multi-criteria preference aggregation framework for sustainable energy planning

Santos-Ramos, Raquel January 2018 (has links)
In the energy field, the decisions need to take into consideration several factors such as the needs of the population, the environment, suitability, capital cost, sustainability, political goals and the actors involved, with their interests and preferences. The lack of homogeneity in all the factors that must be consider makes it necessary to design a process that guides the analysis process of any type of decision-maker. Decision analysis methods have been developed to aid decision-makers identify a problem, determine the criteria to be consider and their importance, recognize the stakeholders that need to be involved and pose the different alternatives to resolve or to best address the problem. These techniques range from simple to more mathematically oriented ones, from single criterion evaluation to multiple criteria, and from purely qualitative or quantitative to mixed techniques. Within the field of decision analysis, multi-criteria techniques are better suited to aid in decision situations in the energy field as these decisions require several considerations beside economic ones. This thesis uses theories and notions of decision analysis to construct a framework to be used in any energy related decision situations by non-experts. The framework tackles common challenges faced by multi-criteria decision analysis methods, including the identification of stakeholders and decision-makers, the aggregation of various decision-makers, preferences and heterogeneous inputs, and the selection of suitable criteria, alternatives and methods.
10

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>

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