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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

The technology selections and cost-benefit analysis of NOx reduction measures-The case study of coal-firing boilers

Lin, Hsin-Yi 04 July 2006 (has links)
Abstract The decrement of Nitrogen Oxide (NOx) emission can slow down the impaction to the natural environment as well as avoiding the global warming become worse continuously. The three coal fired boilers in CSC were designed as capable of multi-fuel burning but its primary fuel is coal. The original designed coal is PCI coal from Australia. The NOx emission generating while using PCI coal is around 320 ppm and can,t meet the local EPA emission requirement set for year 2001, which is 300ppm. To cope with more stringent environmental requirement, the first stage strategy is to evaluate the NOx removal technologies and selecting the optimum one of them to fight against NOx emission. By means of MCDM (Multi-Criteria Decision-Making) methodologies, SNCR is chosen due to its simplicity and acceptable NOx-out ability. The 45% NOx reduction rate can be achieved and the control NOx final output will be lower than 200ppm, which is the promised level to the local EPA. In compromising the NOx reduction requirement and the practical running cost factor, the 240ppm NOx level has been determined for operating the SNCR system. The second stage of NOx reduction evaluation is focused on the coal brands selection. It¡As believed that through the right choose of suitable coal can offer the contribution to both environment and economic. After surveying the different coal composition analysis and carrying out real trial burn, the ADARO coal from Indonesia was picked up from competition and deem as the most environment friendly coal in terms of owning the optimum coal compositions and the lowest pollutants generation including NOx, SO2, as well as ash. As a result, the ADARO coal application is highly successful in the aspects of less pollutant generation and saving cost expenditure caused by the related environment equipment systems operation and maintenance. Obviously, the positive and close relationship between environment and economic has been proved. Base on the real evidence, this paper proves that by choosing the suitable methodologies, the NOx reduction can be accomplished to some extent. The whole environment can be benefited by this action and meanwhile the air pollution tax plus operation and maintenance cost can be reduced further. It¡As hoped that by announcing this paper, the outstanding performance of remarkable NOX reduction outcome and its coat saving advantage can be applied to the whole industrial field. Let¡As work together for the purpose of decreasing the pollutants emission, lightening the harms to the natural environment and fulfilling the duties of protection the all eco system. Key words: Nitrogen Oxide, Selective Non-Catalytic Reduction(SNCR), environmental coal, Multi-criteria decision-making(MCDM)
2

Application of AHP Decision-Making Method for Selecting a 4-axis Machining Center: A Case Study in Mold and Die Industry

Tsai, Jo-Peng 26 July 2008 (has links)
Selection of the right machine tools is an important decision for most manufacturing companies. The quality and efficiency of manufacture are affected by the correct adoption of machine and equipment, and it will result in reducing the cost, increasing the production, and enhancing the flexibility for the diverse type of machining parts in this competitive globalized environment. On the contrary, an incorrect selection can retard the productivity of company. This research presents the procedures of AHP method for selecting 4-axis CNC machining centers including searching the literature of selecting machines, consulting experts with abundant experience of machine tool, translating the unstructured and biased commercial specification to the objective and hierarchical evaluation criteria for selecting machines. In order to experiment the applicability of the AHP model as well as to realize the relative importance of the criteria for the mold design and manufacturing company, a company was invited as the survey objective. This method proposed in this research is general in form and can be applied to the selections of other machine tools for other manufacturing industries. Also, it is hoped that the results of this experimental study will provide a reference for the domestic machinery manufacturing company to develop 4-axis CNC machining centers.
3

A New Census Geography For Turkey Using Geographic Information Systems A Case Study On Cankaya District, Ankara

Kirlangicoglu, Cem 01 June 2005 (has links) (PDF)
Today, population census results are not only fundamental for population counting but also for providing various information to many organizations and people who make research and take decisions about human-related issues. However, statistics produced on the basis of administrative divisions in Turkey are inadequate to meet the needs of most In this study, a new census geography is aimed for Turkey using Geographic Information Systems and Multi Criteria Decision Making methodologies. This new census geography is for statistical purposes only, independent from legal boundaries and generated by the concept of small area statistics. New rules and methodologies are created by taking the United States and the United Kingdom systems as models to reach to the main aim, and then they are applied on a case study area, &Ccedil / ankaya District in Ankara. Through this application process, firstly all the collected graphical and nongraphical raw data are geo-referenced and combined in a common geodatabase. Secondly, this geodatabase is used to understand the differentiation of quality of life indicators across the case study area. This pattern is then used to draw the boundaries of small statistical units of the new census geography in terms of the previously defined population sizes. In conclusion, a nationwide standard census geography hierarchy, which ranges between national level at the top and block level at the bottom, is proposed for use in 2010 Population Census and afterwards.
4

Improving IT Portfolio Management Decision Confidence using Multi-Criteria Decision Making and Hypervariate Display Techniques

Landmesser, John Andrew 01 January 2014 (has links)
Information technology (IT) investment decision makers are required to process large volumes of complex data. An existing body of knowledge relevant to IT portfolio management (PfM), decision analysis, visual comprehension of large volumes of information, and IT investment decision making suggest Multi-Criteria Decision Making (MCDM) and hypervariate display techniques can reduce cognitive load and improve decision confidence in IT PfM decisions. This dissertation investigates improving the decision confidence by reducing cognitive burden of the decision maker through greater comprehension of relevant decision information. Decision makers from across the federal government were presented with actual federal IT portfolio project lifecycle costs and durations using hypervariate displays to better comprehend IT portfolio information more quickly and make more confident decisions. Other information economics attributes were randomized for IT portfolio projects to generate Balanced Scorecard (BSC) values to support MCDM decision aids focused on IT investment alignment with specific business objectives and constraints. Both quantitative and qualitative measures of participant comprehension, confidence, and efficiency were measured to assess hypervariate display treatment and then MCDM decision aid treatment effectiveness. Morae Recorder Autopilot guided participants through scenario tasks and collected study data without researcher intervention for analysis using Morae Manager. Results showed improved comprehension and decision confidence using hypervariate displays of federal IT portfolio information over the standard displays. Both quantitative and qualitative data showed significant differences in accomplishment of assigned IT portfolio management tasks and increased confidence in decisions. MCDM techniques, incorporating IT BSC, Monte Carlo simulation, and optimization algorithms to provide cost, value, and risk optimized portfolios improved decision making efficiency. Participants did not find improved quality and reduced uncertainty from optimized IT portfolio information. However, on average participants were satisfied and confident with the portfolio optimizations. Improved and efficient methods of delivering and visualizing IT portfolio information can reduce decision maker cognitive load, improve comprehension efficiency, and improve decision making confidence. Study results contribute to knowledge in the area of comprehension and decision making cognitive processes, and demonstrate important linkages between Human-Computer Interaction (HCI) and Decision Support Systems (DSS) to support IT PfM decision making.
5

Un cadre de mise en oeuvre du routage mulitcritères de services IP multimédia

MUSHTAQ, Sajjad Ali 16 January 2012 (has links) (PDF)
A dynamic decision making framework implementing multi criteria routing of multimedia services at private-public network border with access technology convergence is presented. The ingredients of the framework include information model, semantics capturing via ontology, information sharing and dissemination mechanisms and rule/policy specifications methodology. The control and management over the infrastructure is carried out by revamping the sole signaling protocols (SIP, diameter and SNMP). DEN-ng is enhanced and tagged in accordance with the requirements over the underlying framework. A dedicated language for the platform is proposed that has its deep roots inside the framework to avoid conflicts and overlapping. A dynamic decision engine is developed for routing the requests/sessions at private-public network border over the underlying multi-homed environment. Multi Criteria Decision Making (MCDM) theory is used for decision computation/calculation and the adapted methods are exploited according to the scenario and decision computation mode while keeping in view the corresponding enforcement mode. A test bed is developed to validate the proposed framework. The proposed system offers higher throughput and lowers call-dropping probability with an add-on susceptible delay.
6

Design of a system to support policy formulation for sustainable biofuel production

Singh, Minerva January 2010 (has links)
The increased demand for biofuels is expected to put additional strain on the available agricultural resources while at the same time causing environmental degradation. Hence, new energy policies need to be formulated and implemented in order to meet global energy needs while reducing the impact of biofuels farming and production. This research focuses on proving a decision support system which can aid the formulation of policies for the sustainable biofuel production. The system seeks to address policy formulation that requires reconciliation of the qualitative aspects of decision making (such as stakeholder’s viewpoints) with quantitative data, which often may be imprecise. To allow this, based on: Fuzzy logic and Multi Criteria Decision Making (MCDM) in the form of Analytical Hierarchy Process (AHP). Using these concepts, three software functionalities, “Options vs. Fuzzy Criteria Matrix”, “Analytical Hierarchy Process” and “Fuzzy AHP” were developed. These were added within the framework of pre-existing base software, Compendium (developed by the Open University, UK). A number of case study based models have been investigated using the software. These models made use of data from the Philippines and India in order to pinpoint suitable land and crop options for these countries. The models based on AHP and Fuzzy AHP were very successful in identifying suitable crop options for India by capturing both the stakeholder viewpoints and quantitative data. The software functionalities are very effective in scenario planning and selection of policies that would be beneficial in achieving a desired future scenario. The models further revealed that the newly developed software correctly identified many of the important issues in a consistent manner.
7

<b>MULTI-CRITERIA ANALYSIS FOR </b><b>HUMAN-LIKE </b><b>DECISION MAKING IN AUTONOMOUS VEHICLE PERATIONS</b>

Aishwarya Sharma (18429147) 25 April 2024 (has links)
<p dir="ltr">Highway safety continues to pose a serious challenge to the social sustainability of transportation systems, and initiatives are being pursued at all levels of government to reduce the high fatality count of 42,000. At the same time, it is sought to ensure higher travel efficiency in order to increase economic productivity. The emergence of automated transportation provides great promise to mitigate these ills of the transportation sector that have persisted for so many decades. With regards to safety, such promise is rooted in the capability of autonomous vehicles to self-drive some or all of the time, thus reducing the impact of inherently errant human driving to which 95% of all crashes have been attributed. With regards to mobility, such promise is guided by the capability of the autonomous vehicle to carry out path planning, navigation, and vehicle controls in ways that are far more efficient than the human brain, thereby facilitating mobility and reducing congestion-related issues such as delay, emissions, driver frustration, and so on.</p><p dir="ltr">Unfortunately, the two key outcomes (safety and mobility) are reciprocal in the sense that navigation solutions that enhance safety generally tend to reduce mobility, and vice versa. As such, there is a need to assign values explicit to these performance criteria in order to develop balanced solutions for AV decisions. Most existing machine-learning-based path planning algorithms derive these weights using a learning approach. Unfortunately, the stability of these weights across time, individuals, and trip types, is not guaranteed. It is necessary to develop weights and processes that are trip situation-specific. Secondly, user trust in automation remains a key issue, given the relatively recent emergence of this technology and a few highly-publicized crashes, which has led to reservations among potential users.</p><p dir="ltr">To address these research questions, this thesis identifies various situational contexts of the problem, identifies the alternatives (the viable trajectories by fitting curves between the vehicle maneuver’s initial and final positions), develops the decision criteria (safety, mobility, comfort), carries out weighting of the criteria to reflect their relative significance, and scales the criteria to develop dimensionless equivalents of their raw values. Finally, a process for amalgamating the overall impacts of each driving decision alternative is developed based on the weighted and scaled criteria, to identify the best decision (optimal trajectory path). This multi-criteria decision making (MCDM) problem involves the collection of data through questionnaire surveys.</p><p dir="ltr">The weights obtained early in the MCDM process could be integrated into any one of two types of planning algorithms. First, they could be incorporated into interpolating curve-based planning algorithms, to identify the optimal trajectory based on human preferences. Additionally, they can be integrated into optimization-based planning algorithms to allocate weights to the various functions used.</p><p dir="ltr">Overall, this research aims to align the behavior of autonomous vehicles closely with human-driven vehicles, serving two primary purposes: first, facilitating their seamless coexistence on mixed-traffic roads and second, enhancing public acceptance of autonomous vehicles.</p>
8

Fan And Pitch Angle Selection For Efficient Mine Ventilation Using Analytical Hierachy Process And Neuro Fuzzy Approach

Taghizadeh Vahed, Amir 01 May 2012 (has links) (PDF)
Ventilation is a critical task in underground mining operation. Lack of a good ventilation system causes accumulation of harmful gases, explosions, and even fatalities. A proper ventilation system provides adequate fresh air to miners for a safe and comfortable working environment. Fans, which provide air flow to different faces of a mine, have great impact in ventilation systems. Thus, selection of appropriate fans for a mine is the acute task. Unsuitable selection of a fan decreases safety and production rate, which increases capital and operational costs. Moreover, pitch angle of fans&rsquo / blades plays an important role in fan&rsquo / s efficiency. Therefore, selection of a fan and its pitch angle, which yields the maximum efficiency, is an emerging issue for an efficient mine ventilation. The main objective of this research study is to provide a decision making methodology for the selection of a main fan and its appropriate pitch angle for efficient mine ventilation. Nowadays, analytical hierarchy process as multi criteria decision making is used, and it yields outputs based on pairwise comparison. On the other hand, Fuzzy Logic as a soft computing method was combined with analytical hierarchy process and combined model did not yield appropriate results / because Fuzzy AHP increased uncertainty ratio in this study. However, fuzzy analytical hierarchy process might be inapplicable when it faces with vague and complex data set. Soft computing methods can be utilized for complicated situations. One of the soft computing methods is a Neuro-Fuzzy algorithm which is used in classification and DM issues. This study has two phases: i) selection of an appropriate fan using Analytical Hierarchy Process (AHP) and Fuzzy Analytical Hierarchy Process (Fuzzy AHP) and ii) selection of an appropriate pitch angle using Neuro-Fuzzy algorithm and Fuzzy AHP method. This study showed that AHP can be effectively utilized for main fan selection. It performs better than Fuzzy AHP because FAHP contains more expertise and makes problems more complex for evaluating. When FAHP and Neuro-Fuzzy is compared for pitch angle selection, both methodologies yielded the same results. Therefore, utilization of Neuro-Fuzzy in situation with complicated and vague data will be applicable.
9

A multi-criteria decision support system using knowledge management and project life cycle approach : application to humanitarian supply chain management / La conception et l’implémentation d’un outil d’aide a la décision multicritères intégrant les concepts de la gestion des connaissances et du cycle de vie : application de la chaîne d'approvisionnement humanitaire

Saksrisathaporn, Krittiya 25 September 2015 (has links)
Cette thèse vise à contribuer à la compréhension des cycle de vie d’une opération humanitaire (HOLC). Gestion de la chaîne d'approvisionnement humanitaire (HSCM) dans un contexte de mise en perspective et dans l’objectif de proposer un modèle décisionnel qui s'applique aux phases de HOLC lors d’une situation réelle. Cela inclut la mise en oeuvre du modèle proposé pour concevoir et développer un outil d'aide à la décision afin d'améliorer les performances de la logistique humanitaire tant dans les opérations de secours nationaux qu’internationaux.Cette recherche est divisée en trois phases. La première partie vise à présenter le sens de l'étude ; la zone de recherche prise en compte pour la gestion de la chaîne d'approvisionnement (SCM) doit être clairement définie. La première phase consiste à clarifier et définir le HSCM HL, la gestion de la chaîne d'approvisionnement commerciale (CSCM) et le SCM, ainsi que la relation entre ces différents éléments. La gestion du cycle de vie du projet (PLCM) et les différentes approches sont également présentés. La compréhension de la différence entre la gestion du cycle de vie du projet (PLM) et la PLCM est également nécessaire, cela ne peut être abordé dans la phase de cycle de vie de l'opération humanitaire. De plus, les modèles Multiple-Criteria Decision Making (MCDM) et l’aide à la décision concernant le HL sont analysés pour établir le fossé existant en matière de recherche. Les approches MCDM qui mettent en oeuvre le système d'aide à la décision (DSS) et la manière dont le MAS a été utilisé dans le contexte HSCM sont étudiées.La deuxième phase consiste en la proposition d’un modèle décisionnel fondé sur l’approche MCDM à l'appui de la décision du décideur avant qu'il/elle prenne des mesures. Ce modèle prévoit le classement des alternatives concernant l'entrepôt, le fournisseur et le transport au cours des phases de HOLC. Le modèle décisionnel proposé est réalisée en 3 scénarios. I. La décision en 4phases HOLC – opération de secours internationale de la Croix-Rouge Française (CRF). II. La décision en3phases HOLC – opération nationale dela Croix-Rouge thaïlandaise (TRC). III. La décision au niveau de la phase de réponse HOLC – opération internationale du TRC dans quatre pays. Dans cette phase, le scénario I et II sont réalisés étape par étape au travers de calculs numériques et formules mathématiques. Le scénario III sera présenté dans la troisième phase. Pour établir trois scénarios, les données internes recueillies lors des entretiens avec le chef de la logistique de la Croix-Rouge Française, et le vice-président de la fondation de la Coix-Rouge thaïlandaise, seront utilisées. Les données externes proviennent de chercheurs qui sont des experts dans le domaine HL ou le champ du HSCM, de la littérature, et de sources issues des organismes humanitaires (documents d’ateliers, rapports, informations publiées sur leurs sites officiels).Dans la troisième phase, une application Internet multi-critères (decision support system MCDSS WB) mettant en oeuvre le modèle proposé est élaborée. Afin d'atteindre une décision appropriée en temps réel, le WB-MCDSS est développé sur la base d’un protocole client-serveur et est simple à utiliser. Le dernier mais non le moindre ; une application de validation du modèle est réalisée à l'aide de l'approche de l'analyse de sensibilité. / This thesis aims to contribute to the understanding of HOLC in context of the HSCM and to propose a decision model which applies to the phases of HOLC the decision making regarding a real situation . This include the implementation of the proposed model to design and develop a decision support tool in order to improve the performance of humanitarian logistics in both national and international relief operations.This research is divided into three phases; the first phase is to clarify and define HL among HSCM, commercial supply chain management (CSCM) and SCM and their relationship. Project Life Cycle Management (PLCM) approaches are also presented. The difference between project life cycle management (PLM) and PLCM is also required to distinguish a clear understanding which can be addressed in the phase of humanitarian operation life cycle. Additionally, the literature of Multiple-Criteria Decision Making (MCDM) models and existing decision aid system for HL are analyzed to establish the research gap. The MCDM approaches which implement the decision support system (DSS) and lastly how DSS has been used in the HSCM context.The second phase is to propose a decision model based on MCDM approaches to support the decision of the decision maker before he/she takes action. This model provides the ranking alternatives to warehouse, supplier and transportation over the phases of HOLC. The proposed decision model is conducted in 3 scenarios; I. The decision in 4-phase HOLC, international relief operation of French Red Cross (FRC). II. The decision on 3-phase HOLC, national operation by the Thai Red Cross (TRC). III. The decision on response phase HOLC, international operation by the FRC in four countries. In this phase, the scenario I and II are performed step by step though numerical calculation and mathematical formulas. The scenario III will be presented in the third phase.In the third phase, an application of web-based multi-criteria decision support system (WB-MCDSS) which implement the proposed model is developed. The web-based multi-criteria decision support system is developed based on the integration of analytical hierarchy process (AHP) and TOPSIS approaches. In order to achieve an appropriate decision in a real time response, the WB-MCDSS is developed based on server-client protocol and is simple to operate. Last but not least, a validation application of the model is performed using the sensitivity analysis approach.

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