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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.
231

Jämförelse av IT-system för säljrapporter : Framtagning av metod för jämförelse och med applicering i en fallstudie / Comparison of IT systems for sales reports : Development of methods for the comparison and apply in a case study

Swedenborg, Tobias, Brötmark, Karl-Anton January 2016 (has links)
Valet av IT-system kan vara en omfattande process som trots många iblandade kan resultera i ett misslyckade, vilket kan leda till stora och oförutsedda kostnader. Om jämförelsen inte sker enligt en säker och beprövad process är risken större att valet blir fel då det snarare grundas på känsla och marknadsföring än en opartisk jämförelse. Företaget Genero Solutions erbjuder en IT-lösning för säljstyrning som bland annat tillhandahåller rapporter över fältsäljkårers besöksstatistik och ser ett behov av ett bättre rapportsystem som ger granskare av dessa rapporter större frihet vid exploatering av data. Många leverantörer av IT-system inom Business Intelligence erbjuder den här typen av rapportsystem, vilket gör det än svårare att välja vilket system som passar Genero Solutions bäst. Eftersom det finns en väldig mängd av dessa system är risken stor att valet blir fel om jämförelsen inte sker enligt en säker process, utan istället grundas på känsla och marknadsföring. Denna rapport innehåller en metod som jämför tre olika rapportsystem baserad på en etablerad jämförelsemetod för att undersöka möjligheten att åstadkomma ett vetenskapligt resultat. Jämförelsen granskar de tre Business Intelligence systemen Microsoft Powber BI, The Diver Solution och Qlik Sense och baseras på Analytic Hierarchy Process (AHP). Rapporten resulterar i motiverad metod som är lämpad för undersökningen samt en rekommendation till Genero Solutions av det rapportsystem som är bäst lämpat. / Selecting the right IT-system might be an extensive process which, despite many people involved, might lead to a failure which can mean high and unforeseen costs. If the comparison of systems isn’t done according to a proven method there is a higher risk that the final choice of IT-system is based on emotions and good marketing rather than a straight and fair comparison. Genero Solutions offers an IT-solution for sales control which is partly providing reports containing statistics from the sales force on field. Genero Solutions is in need of a better reporting system which gives the inspector of the reports more flexibility when exploring data. There are many providers within Business Intelligence who is offering this kind of reporting service, which makes it even harder choosing the system fitting Genero Solutions needs. This report develops a method which is based on scientific theories and the established comparison method Analytic Hierarchy Process (AHP), aiming to achieve a scientifically proved result and apply it by examine the Business Intelligence systems Microsoft Power BI, The Diver Solution and Qlik Sense The result of this report in a motivated method that is suited for this investigation and also a recommendation for which system that is best suited for Genero Solutions needs.
232

Impacts on sustainable development of two CDM projects : A comparison using AHP method

Qirui, Yang January 2010 (has links)
Nowadays the mitigation of climate change and the reduction of greenhouse gases are one of the priorities in the international affairs. Clean Development Mechanism (CDM) is one of the products generated according to this request. For China, CDM brings advanced technologies in terms of energy saving and emission reduction, and driving forces for sustainable development, hereby the development of CDM projects is in full swing in China so far. However, it is not easy to decide which type of CDM projects is suitable for a certain city or region, which project contributes more to sustainable development compared with others, when it comes to several alternatives. In this case, decision-makers require a tool to help make a rational decision. As one of the approaches of assisting in making decisions, the Analytic Hierarchy Process (AHP) is able to provide assistance for decision-makers to compare the contribution of discrepant CDM projects to sustainable development. Moreover, a case study is taken between two typical CDM projects: HFC23 decomposition project and small-scale hydropower project, so as to check if AHP is useable. The result of the case study indicates that HFC23 decomposition project contributes more than small-scale hydropower plant project to sustainable development, which is not in line with China’s CDM development trend for these two projects (NCCCC, 2005), due to the different represented interests of the study group and the real decision-makers. Nevertheless, the result is rational and valid since there is nothing wrong with the AHP method and its application. In addition, in order to improve the effect of assisting in decision making, AHP was tried to be improved in three respects: impairing subjectiveness, avoiding rank reversal and improving accuracy. Even though for AHP itself, DEA/AHP approach could successfully eliminate the subjectiveness, however when it comes to this very case: compare CDM projects in terms of contribution to sustainable development in China, it cannot play an effective role. Moreover, PCA/AHP method cannot eliminate the subjectiveness at the root either. The framework method provides a possibility in theory to increase objectiveness. Two expects provided a feasible way to avoid rank reversal in their article, and the two pathways of improving results accuracy mentioned in this thesis are considered inappropriate in this case. On the other side, concerning AHP application, how to covert realistic issues to AHP structure, how to get desirable initial information, and how to avoid limitation generated by considerable criteria, sub-criteria and alternatives are considered as the difficulties which should be paid attention. In future, AHP could be applied frequently and effectively concerning providing assistance in making decisions in China, if the stakeholders as many as possible are involved in decision-making process.
233

Application of geographic Information system and remote sensing in multiple criteria analysis to identify priority areas for biodiversity conservation in Vietnam

Vu, Xuan Dinh 11 February 2021 (has links)
There has been an increasing need for methods to define priority areas for biodiversity conservation since the effectiveness of biodiversity conservation in protected areas planning depends on available resources (human resources and funds) for the conservation. The identification of priority areas requires the integration of biodiversity data together with social data on human pressures and responses. However, the deficit of comprehensive data and reliable methods are key challenges in zoning where the demand for conservation is most urgent and where the outcomes of conservation strategies can be maximized. In order to fill this gap, the environmental model Pressure–State–Response (PSR) was applied to suggest a set of criteria to identify priority areas for biodiversity conservation. The empirical data have been compiled from 185 respondents, categorizing into three main groups: Governmental Administration, Research Institutions, and Protected Areas in Vietnam, by using a well-designed questionnaire. Then, the Analytic Hierarchy Process (AHP) theory was used to identify the weight of all criteria. These results show that three main factors could identify the priority level for biodiversity conservation: Pressure, State, and Response, with weights of 41%, 26%, and 33%, respectively. Based on the three factors, seven criteria and 17 sub-criteria were developed to determine priority areas for biodiversity conservation. In addition, this study also indicates that the groups of Governmental Administration and Protected Areas put a focus on the “Pressure” factor while the group of Research Institutions emphasized the importance of the “Response” factor in the evaluation process. Then these suggested criteria were applied by integrating with Geographic Information System (GIS) and Remote Sensing (RS) to define priority areas for biodiversity conservation in a particular conservation area (Pu Luong-Cuc Phuong area) in Vietnam. The results also reveal the proportion of very high and high priority areas, accounting for 84.9%, 96%, and 65.9% for Cuc Phuong National Park, Pu Luong Nature Reserve, and Ngoc Son Ngo Luong Nature Reserve, respectively. Based on these results, recommendations were provided to apply the developed criteria for identifying priority areas for biodiversity conservation in Vietnam.:Acknowledgement I Abstract III Table of contents IV List of figures VI List of tables X Acronyms and Abbreviations XII Chapter 1. Introduction 1 1.1. Problem statement and motivation 1 1.2. Research objectives and questions 2 1.3. Study contribution 3 1.4. Thesis structure 6 Chapter 2. Literature review 8 2.1. Background information on Vietnam 8 2.2. Environmental Pressure-State-Response model 11 2.3. Defining criteria for biodiversity conservation 13 2.4. Application of GIS and RS for biodiversity conservation 16 Chapter 3. Research methodology 19 3.1. Study areas 19 3.2. Data collection 23 3.3. Analytic Hierarchy Process 25 3.4. Remote Sensing 27 3.5. Geography Information System 35 3.6. Climate change scenarios 40 Chapter 4. Establishment of criteria 42 4.1. Summary of responses 44 4.2. Statistic of pairwise comparison 46 4.3. Weights of criteria based on all respondents 48 4.4. Weights of criteria based on groups 60 Chapter 5. Application of Criteria 64 5.1. Mapping criteria 64 5.2. Synthesis of multiple criteria 144 Chapter 6. Conclusions and recommendations 158 6.1. Establishment of criteria 158 6.2. Application of criteria 161 6.3. Recommendations 165 References 167 Appendix I. Questionnaire 197 Appendix II. Establishment of criteria 207 Appendix III. Application of criteria 234
234

EN JÄMFÖRELSE MELLAN TEGEL- OCH SEDUMTAK UTIFRÅN ETT MILJÖ- OCH KOSTNADSPERSPEKTIV / A COMPARISON BETWEEN CERAMIC ROOF TILES AND SEDUM FROM AN ENVIROMENTAL AND ECONOMICAL PERSPECTIVE

Eriksson, Ted, Almersved, Simon January 2020 (has links)
Purpose: The housing demand remains high in Sweden and according to Boverket (2017) approximately 600 000 homes need to be built from 2017 to 2025. In order to make this a value-creating investment, the focus should be on trying to meet sustainable social, economic and environmental goals. The life cycle perspective should be the starting point for analyzing buildings. Analyzes such as LCA and LCC can be good tools for examining buildings from an environmental and cost perspective. These analyzes can be used to provide a broader basis for decision making in the future. The analyzes can also increase the likelihood of meeting the aforementioned social, economic and environmental goals.  The aim of the study is to investigate which roof type that performs best from an environmental and a cost perspective between the ceramic roof tiles and sedum roof. The goal is also to provide a basis for companies and customers in the construction industry for decision making. The research questions in the study are as following;  <li data-leveltext="" data-font="Symbol" data-listid="2" data-aria-posinset="1" data-aria-level="1">How does ceramic roof tiles and sedum roofs perform from an environmental perspective?  <li data-leveltext="" data-font="Symbol" data-listid="1" data-aria-posinset="2" data-aria-level="1">What does the cost of ceramic roof tiles and sedum roofs look like during construction versus their entire service life?  <li data-leveltext="" data-font="Symbol" data-listid="1" data-aria-posinset="1" data-aria-level="1">What does a comparison of both roof types look like based on the above analyses?  Method: To reach the goal, the methods literature studies, document reviews and interviews has been used. These have then been supplemented with a life cycle analysis (LCA), a life cycle cost analysis (LCC) and a multi-criteria analysis (MKA).  Findings: From an environmental perspective, the sedum roof had lower carbon dioxide emissions and used primary energy than the ceramic roof tiles, in contrast, the ceramic roof tiles performed better with the emissions that affects the ozone layer. From a cost perspective, the sedum roof performed better at the time of construction while the ceramic roof tiles performed better when considering the whole life cycle. When comparing the roof types with the help of weightings from an expert group in Europe, the ceramic roof tiles performed better and was ranked number one among the alternatives.  Implications: Conclusions drawn from the study is that sedum roof performs better in a life cycle analysis and thus have a less negative impact on the environment. Sedum roofs are cheaper compared to ceramic roof tiles in the first two years, then the ceramic roof tiles become cheaper until the year 30. From year 30 until demolition, the sedum roofs are cheaper and finally after demolition the ceramic roof tiles becomes the cheapest. In a multicriteria analysis, the ceramic roof tiles perform a bit better from an environmental and cost perspective.  Limitations: The study is limited to only two different roof types and doesn´t consider the differences required for the construction under the roofing felt. Transport is not included in the calculations while the working hours to climb the roof for maintenance of the sedum roof and the costs for repairs to irregular damage to the ceramic roof tiles are also not included in the lifecycle cost analysis.  Keywords: Lifecycle Analysis, LCA, Lifecycle Cost Analysis, LCC, Multicriteria Analysis, MKA, COPRAS, Analytic Hierarchy Process, AHP. / Syfte: Bostadsbehovet är fortsatt stort i Sverige och enligt Boverket (2017) behövs det byggas cirka 600 000 bostäder från år 2017 till 2025. För att byggnaderna ska kunna bli en värdeskapande investering bör fokus vara på att försöka uppfylla hållbara sociala, ekonomiska och miljömässiga samhällsmål. Livscykelperspektivet bör vara utgångspunkten för att analysera byggnader. Analyser som LCA och LCC kan vara bra verktyg för att undersöka byggnader ur ett miljö-och kostnadsperspektiv. Dessa analyser kan användas för att ge ett bredare underlag för beslutsfattning i framtiden. Analyserna kan också öka sannolikheten att de tidigare nämnda samhällsmålen uppfylls.  Målet med studien är att undersöka vilket av tegel- och sedumtak som presterar bäst utifrån ett miljö- och kostnadsperspektiv. Målet är också att kunna ge ett underlag till företag och kunder inom byggbranschen. Frågeställningarna i studien är följande;  <li data-leveltext="" data-font="Wingdings" data-listid="3" data-aria-posinset="1" data-aria-level="1">Hur presterar tegel- och sedumtak utifrån ett miljöperspektiv?  <li data-leveltext="" data-font="Wingdings" data-listid="3" data-aria-posinset="2" data-aria-level="1">Hur ser kostnaderna ut för tegel- och sedumtak vid byggnationen kontra hela livslängden?  <li data-leveltext="" data-font="Wingdings" data-listid="3" data-aria-posinset="1" data-aria-level="1">Hur ser en jämförelse ut mellan båda taktyperna utifrån ovanstående analyser?  Metod: För att nå målet har metoderna litteraturstudie, dokumentgranskning och intervjuer använts. Dessa har sedan kompletterats med en livscykelanalys (LCA), en livscykelkostnadsanalys (LCC) samt en multikriterieanalys (MKA).  Resultat: Ur ett miljöperspektiv presterar sedumtak bättre för koldioxidutsläppet samt för den primära använda energin, däremot presterar tegeltak bättre för utsläpp som påverkar ozonlagret. Ur ett kostnadsperspektiv presterar sedumtak bättre vid uppförandet medan tegeltaket presterar bättre för en livscykelkostnad. Vid en jämförelse av taktyperna med hjälp av en viktning från en expertgrupp i Europa presterade tegeltak bättre och blev rangordnad nummer ett av alternativen.  Konsekvenser: Slutsatser som dras av studien är att sedumtak presterar bättre i en livscykelanalys och har därmed en mindre negativ påverkan på miljön. Sedumtaket är billigare jämfört med tegeltak de två första åren, därefter blir tegeltak billigare fram till år 30. Från år 30 till rivning är sedumtaket billigare och slutligen efter rivning är tegeltaket billigast. Vid en multikriterieanalys presterar tegeltak lite bättre utifrån ett miljö- och ett kostnadsperspektiv.  Begränsningar: Studien är begränsad till enbart två taktyper och tar inte heller hänsyn till skillnader som krävs för konstruktionen under underlagspappen. Transporter är ej inkluderade i beräkningarna medan arbetstimmar för att klättra upp på taket vid underhåll av sedumtaket samt kostnader för reparationer till oregelbundna skador på tegelpannor är ej medräknat i livscykelkostnadsanalysen.  Nyckelord: Livscykelanalys, LCA, livscykelkostnadsanalys, LCC, multikriterieanalys, MKA, COPRAS, Analytic Hierarchy Process, AHP.
235

Contributions to the design of pumping stations in water distribution networks considering technical, economic and environmental aspects.

Briceño León, Christian Xavier 03 May 2023 (has links)
Tesis por compendio / [ES] El consumo energético de una estación de bombeo (EB) representa el mayor consumo de energía de un sistema de de distribución de agua. Adicionalmente, otros problemas como el cambio climático, el estrés hídrico y emisión de gases de efecto invernadero conducen a la necesidad de optimizar este tipo de instalaciones, tanto en su diseño como en su operación. La presente tesis doctoral consta de tres etapas de desarrollo. La primera etapa desarrolla una metodología de optimización de la operación de EB. La segunda etapa desarrolla un método de diseño de estaciones de bombeo considerando aspectos técnicos y económicos basados en el método AHP (Analytic Hierarchy Process, del Ingles). Finalmente, la tercera etapa es una mejora de la segunda añadiendo aspectos ambientales y consideración de variabilidad de la demanda. Una de las principales contribuciones es el desarrollo de una metodología para la optimización del funcionamiento de una EB. Esta metodología se basa en el uso de la curva de consigna y una operación combinando bombas de velocidad fija (BVF) y bombas de velocidad variable (BVV). El objetivo de este método es determinar el número óptimo de BVF y BVV en para cualquier caudal minimizando el consumo energético total de la EB. Esta metodología corrige la eficiencia de BVV determinada por las leyes de semejanza e incluye una formulación matemática de la eficiencia del variador de frecuencia. El diseño convencional de EB se basa la minimización del coste del ciclo de vida (CCV); suma de costes de inversión, operación y mantenimiento. La segunda etapa de la tesis, desarrolla un método integral de diseño de EB considerando aspectos técnicos y económicos aplicando el método AHP. La metodología propuesta consta de tres fases. La primera fase está relacionada la definición de los datos requeridos de la EB y permite definir los modelos factibles para la red. La segunda fase está relacionada con la definición de las posibles soluciones y su evaluación con los criterios técnicos y económicos. La tercera fase está relacionada con el cálculo del frente de Pareto del conjunto de soluciones obtenidas y la aplicación del método AHP. La metodología desarrollada en la segunda etapa de la tesis presenta cuatro limitaciones. La primera es no considerar los criterios medioambientales en el diseño de la EB. La segunda es no considerar la optimización del funcionamiento de una EB definido en la primera etapa. LA tercera está relacionada con la escala utilizada en el método AHP. La cuarta es la consideración de un único patrón de consumo en la estación de bombeo. Por ello, en la tercera etapa de la tesis se desarrolla una nueva propuesta de metodología de diseño de EB que pretende solventar estos problemas. Este nuevo método considera criterios medioambientales como el MEI, las emisiones de efecto invernadero o la eficiencia del método de regulación en la EB. El método incluye también una propuesta de modificación de la escala tradicional de valoración clásica del AHP. Las metodologías propuestas se han validado de forma comparativa con dos redes de distribución de agua (redes CAT y TF). Sobre ambas redes se compararon tanto los diferentes métodos propuestos como su comparativa con un planteamiento clásico del problema de diseño de una EB. En resumen, el la tesis recoge una metodología estandarizada para el diseño de cualquier tipo de EB (para agua potable, para riego etc.) considerando la configuración de bombeo más adecuada, haciendo uso de una variabilidad de la demanda, y considerando diferentes tipos de criterios (técnicos, económicos y ambientales) a través de un análisis multi criterio de toma de decisiones. / [CA] El consum energètic d'una estació de bombament (EB) representa el consum d'energia més gran d'un sistema de distribució d'aigua. Addicionalment, altres problemes com el canvi climàtic, l'estrès hídric i l'emissió de gasos d'efecte hivernacle condueixen a la necessitat d'optimitzar aquest tipus d'instal¿lacions, tant pel que fa al disseny com a l'operació. Aquesta tesi doctoral consta de tres etapes de desenvolupament. La primera etapa desenvolupa una metodologia d"optimització de l"operació d"EB. La segona etapa desenvolupa un mètode de disseny d'estacions de bombament considerant aspectes tècnics i econòmics basats en el mètode AHP (Analytic Hierarchy Process, de l'Angles). Finalment, la tercera etapa és una millora de la segona afegint-hi aspectes ambientals i consideració de variabilitat de la demanda. Una de les contribucions principals és el desenvolupament d'una metodologia per optimitzar el funcionament d'una EB. Aquesta metodologia es basa en lús de la corba de consigna i una operació combinant bombes de velocitat fixa (BVF) i bombes de velocitat variable (BVV). L'objectiu d'aquest mètode és determinar el nombre òptim de BVF i BVV en qualsevol cabal minimitzant el consum energètic total de l'EB. Aquesta metodologia corregeix l"eficiència de BVV determinada per les lleis de semblança i inclou una formulació matemàtica de l"eficiència del variador de freqüència. El disseny convencional dEB es basa la minimització del cost del cicle de vida (CCV); suma de costos dinversió, operació i manteniment. La segona etapa de la tesi desenvolupa un mètode integral de disseny d'EB considerant aspectes tècnics i econòmics aplicant el mètode AHP. La metodologia proposada consta de tres fases. La primera fase està relacionada amb la definició de les dades requerides de l'EB i permet definir els models factibles per a la xarxa. La segona fase està relacionada amb la definició de les possibles solucions i la seva avaluació amb criteris tècnics i econòmics. La tercera fase està relacionada amb el càlcul del front de Pareto del conjunt de solucions obtingudes i laplicació del mètode AHP. La metodologia desenvolupada a la segona etapa de la tesi presenta quatre limitacions. La primera és no considerar els criteris mediambientals en el disseny de lEB. La segona és no considerar l'optimització del funcionament d'una EB definit a la primera etapa. La tercera està relacionada amb l'escala utilitzada al mètode AHP. La quarta és la consideració d'un únic patró de consum a l'estació de bombament. Per això, a la tercera etapa de la tesi es desenvolupa una nova proposta de metodologia de disseny d'EB que pretén resoldre aquests problemes. Aquest nou mètode considera criteris mediambientals com el MEI, les emissions amb efecte d'hivernacle o l'eficiència del mètode de regulació a l'EB. El mètode també inclou una proposta de modificació de l'escala tradicional de valoració clàssica de l'AHP. Les metodologies proposades han estat validades de manera comparativa amb dues xarxes de distribució d'aigua (xarxes CAT i TF). Sobre les dues xarxes es van comparar tant els diferents mètodes proposats com la comparativa amb un plantejament clàssic del problema de disseny d'una EB. En resum, la tesi recull una metodologia estandarditzada per al disseny de qualsevol tipus d'EB (per a aigua potable, per a reg etc.) considerant la configuració de bombament més adequada, fent ús d'una variabilitat de la demanda, i considerant diferents tipus de criteris (tècnics, econòmics i ambientals) mitjançant una anàlisi multicriteri de presa de decisions. / [EN] Energy consumption of a pumping station (PS) represents the largest energy consumption of a water distribution system. Additionally, other problems such as climate change, water stress and greenhouse gas emissions lead to the need to optimize this type of facilities, both in their design and operation. This doctoral thesis consists of three stages of development. The first stage develops a methodology to optimize the operation of the PS. The second stage develops a pumping station design method considering technical and economic aspects based on the AHP (Analytic Hierarchy Process) method. Finally, the third stage is an improvement of the second stage by adding environmental aspects and demand variability consideration. One of the main contributions is the development of a methodology for the optimization of the operation of a PS. This methodology is based on the use of the set point curve and an operation combining fixed speed pumps (FSP) and variable speed pumps (VSP). The objective of this method is to determine the optimum number of FSP and VSP at any given flow rate while minimizing the total energy consumption of the PS. This methodology corrects the VSP efficiency determined by the similarity laws and includes a mathematical formulation of the variable frequency drive efficiency. Conventional PS design is based on the minimization of the life cycle cost (LCC); the sum of investment, operation and maintenance costs. The second stage of the thesis develops an integral method of PS design considering technical and economic aspects by applying the AHP method. The proposed methodology consists of three phases. The first phase one is related to the definition of the required data of the PS and allows defining the feasible models for the network. The second is related to the definition of the possible solutions and their evaluation with technical and economic criteria. The third phase is related to the calculation of the Pareto front of the set of solutions obtained and the application of the AHP method. The methodology developed in the second stage of the thesis has four limitations. The first one is not considering environmental criteria in the design of the PS. The second is not considering the optimization of the operation of a PS defined in the first stage of the thesis. The third is related to the scale used in the AHP method. The fourth is the consideration of a single consumption pattern in the pumping station. Therefore, in the third stage of the thesis, a new proposed methodology for the PS design is developed to solve these problems. This new method considers environmental criteria such as MEI, greenhouse emissions or the efficiency of the PS control method. The method also includes a proposed modification of the traditional AHP classical rating scale. The proposed methodologies have been comparatively validated with two water distribution networks (CAT and TF networks). For both networks, both the different proposed methods and their comparison with a classical approach to the design problem of a PS were compared. In summary, the thesis presents a standardized methodology for the design of any type of PS (for drinking water, irrigation, etc.) considering the most appropriate pumping configuration, making use of demand variability, and considering different types of criteria (technical, economic and environmental) through a multi-criteria decision making analysis. / Briceño León, CX. (2023). Contributions to the design of pumping stations in water distribution networks considering technical, economic and environmental aspects [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/193080 / Compendio
236

[en] OPTIMIZATION OF THE MAINTENANCE SCHEDULE FOR THE TURBINES OF A HYDROELECTRIC PLANT / [pt] OTIMIZAÇÃO DA AGENDA DE MANUTENÇÃO DAS TURBINAS DE UMA USINA HIDRELÉTRICA

PATRICIA DE SOUSA OLIVEIRA 29 April 2021 (has links)
[pt] O planejamento do cronograma de manutenção de unidades geradoras de usinas hidrelétricas é assunto de grande interesse para diversos agentes do setor de energia brasileiro. Uma abordagem correta para este problema, pode prevenir a degradação dos ativos físicos e minimizar a probabilidade de desligamentos forçados de seus equipamentos. Logo, as estratégias operacionais dos agentes são também influenciadas pelo cronograma de manutenção das turbinas. Porém, o sistema brasileiro possui algumas particularidades, a qual os grupos econômicos que vencem o leilão para a construção de novas usinas hidrelétricas, atendam a uma série de especificações técnicas, dentre elas, o Fator de Disponibilidade (FID). O FID é diretamente influenciado pelas horas de manutenção realizadas na usina e, em caso de desempenho abaixo do estipulado nos contratos de concessão, pode acarretar em perdas financeiras aplicadas pela o agente regulador. Com essa motivação em mente, o presente trabalho propõe uma metodologia para Programação da Agenda da Manutenção de Geradores de uma usina hidrelétrica, desenvolvendo um modelo matemático para determinar o momento ideal para realizar a manutenção, considerando restrições operacionais e aspectos regulatórios de usinas hidrelétricas. O trabalho propõe também, a obtenção de um ranking das turbinas com a utilização do método Analytic Hierarchy Process (AHP), com base nos indicadores de manutenção da usina hidrelétrica estudada. O objetivo da classificação gerada é fornecer subsídio para auxiliar o planejamento das manutenções, de forma a aumentar a disponibilidade dos equipamentos. A metodologia de otimização proposta para este problema é feita através de Programação Linear Inteira Mista (PLIM), onde as variáveis inteiras consistem no estado de operação e data de início da manutenção de cada unidade geradora. A representação do parque hidrotérmico é desafiadora, principalmente, devido à estocasticidade das vazões naturais afluentes. Ao final, para validar a modelagem proposta, é realizado um estudo de caso para uma planta real de grande porte do sistema brasileiro, a Usina Hidrelétrica Santo Antônio. / [en] The planning of the maintenance schedule of hydroelectric power plant generating units is a matter of great interest to several agents in the Brazilian energy sector. A correct approach to this problem can prevent the degradation of physical assets and minimize the likelihood of forced shutdown of your equipment. Therefore, the agents operational operations are also influenced by the turbine maintenance schedule. However, the Brazilian system has some particularities, which the economic groups that win the auction for the construction of new hydroelectric plants, meet a series of technical specifications, among them, the Availability Factor (AFA). The AFA is directly influenced by the hours of maintenance performed at the plant and, in case of performance below the stipulated in the concession contracts, it can result in financial losses applied by the regulatory agent. With this motivation in mind, the present work proposes a methodology for Programming the Maintenance Schedule of Generators of a hydroelectric plant, developing a mathematical model to determine the ideal moment to carry out the maintenance, considering operational restrictions and regulatory aspects of hydroelectric plants. The work also offers to obtain a ranking of the turbines using the Analytic Hierarchy Process (AHP) method, based on the maintenance indicators of the studied hydroelectric plant. The purpose of the generated classification is to provide subsidies to assist the planning of maintenance, in order to increase the availability of equipment. The optimization methodology proposed for this problem is done through Mixed Integer Linear Programming (MILP), where the entire variables consist of the state of operation and start data for the maintenance of each generating unit. The representation of the hydrothermal park is challenging, mainly due to the stochasticity of the affluent natural flows. At the end, to validate the proposed modeling, a case study is carried out for a real large plant in the Brazilian system, the Santo Antônio Hydroelectric Plant.
237

An Evaluation of Testing Frameworks for Beginners inJavaScript Programming : An evaluation of testing frameworks with beginners in mind / En utvärdering av testramverk för nybörjare i JavaScript

Aroush, Georgek January 2022 (has links)
Software testing is an essential part of any development, ensuring the validity and verification of projects. As the usage and footprint of JavaScript expand, new testing frameworks in its community have made statements about being the best overall solution using minimal intervention from developers. The statements from these frameworks about being the greatest can make it difficult for JavaScript beginners to pick a framework that could affect current and future projects. By comparing different types of frameworks and establishing a guideline for others to do the same, it becomes easier for beginners and others to choose a framework according to their own required needs. The overall method uses Mario Bunge’s scientific method via stages, which helps validate the thesis as scientific. Research, empirical data from a qualitative, and objective data from a survey decide the criteria, their priority (to determine their impact and hierarchy), what frameworks to include, and how to compare them. The frameworks Jest, AVA, and Node TAP are compared based on the main criteria of simplicity, documentation, features, and their sub-criteria. Evaluating the frameworks and ranking their performance in each criterion was done through an experiment conducted on a pre-made website without any testing included. The analytic hierarchy process is the primary method used to combine the information gathered and output a result. It makes it possible to create a priority hierarchy for each criterion and subsequently makes it possible to evaluate the choices available on their fulfillment of those criteria. One of these choices will eventually be an overall more suitable fit as the optimal framework for the research question. Combining the survey and experiment data into the analytic hierarchy process revealed that Jest fit the previous criteria better than AVA and Node TAP because of Jest’s better learning curve and Stack overflow presence. AVA was just behind in those areas, while Node TAP had a poor fit for all sub-criteria compared to the other two. AVA’s almost similar evaluation to Jest shows how the open-source community and small development teams can keep up with solutions from big corporations. / Programvarutestning är en viktig del av all utveckling, för att säkerställa giltigheten och verifieringen av projekt. Tack vare JavaScripts expandering och användning, så har nya testramverk dykt upp som anser sig vara den bästa lösningen för utvecklare. Dessa påståenden kan göra det svårt för nybörjare inom JavaScript-utveckling att bestämma sig för vilket ramverk de borde använda, vilket kan påverka deras arbete och framtida projekt. Genom att jämföra dessa ramverk och etablera riktlinjer för andra nybörjare, blir det simpelt för olika demografiska grupper att välja rätt testramverk enligt deras egna åsikter. Den övergripande metoden använder Mario Bunges vetenskapliga metod, vilken använder flera steg för att omvandla hypotesen inom arbetet till en vetenskaplig rapport. Forskning och empirisk information från kvalitativa undersökningar, samt objektiva insamlingar från undersökningar, har använts för att bestämma enligt vilka kriterier dessa ramverk ska jämföras, vilken prioritering dessa kriterier har för nybörjare, vilka testramverk som ska användas och hur ramverken ska jämföras. Testramverken Jest, AVA och Node TAP har jämförts baserat på huvudkriterierna enkelhet, dokumentation och funktionalitet, dessa kriterier innehåller även underkriterier. Evalueringen av dessa ramverk och deras grad av prestanda inom dessa kriterier gjordes genom experimentellt utförande och användning inom en förhandsgjord hemsida utan någon form av testning inkluderad. Den analytiska hierarkiska processen var den primära metoden som användes för att kombinera den insamlade informationen till ett slutgiltigt resultat. Detta för att en prioriteringshierarki kan skapas för all kriterier, och gör det även möjligt att evaluera all ramverk inom dessa kriterier. Ett av dessa ramverk kommer eventuellt beräknas som det bästa alternativet, och på så sätt hjälpa besvara huvudfrågan. Kombinationen av resultaten från undersökningen och experimenten gav att Jest passar bäst till nybörjare, baserat på kriterierna och deras prioriteringsrang, detta tack vare att Jest har bättre inlärningskurva och Stack Overflow-närvaro jämfört med AVA och Node TAP. AVA ligger precis efter inom dessa kriterier, medan Node TAP har betydligt sämre prestanda inom alla kriterier. AVA:s närliggande kapacitet till Jest bevisar att mindre grupper av utvecklare kan komma upp med bra lösningar precis som större företag.
238

The Development of a Hybrid Knowledge-Based System for Designing a Low Volume Automotive Manufacturing Environment. The Development of A Hybrid Knowledge-Based (KB)/Gauging Absences of Pre-Requisites (GAP)/Analytic Hierarchy Process (AHP) System for the Design and Implementation of a Low Volume Automotive Manufacturing (LVAM) Environment.

Mohamed, N.M.Z.Nik January 2012 (has links)
The product development process for the automotive industry is normally complicated, lengthy, expensive, and risky. Hence, a study on a new concept for Low Volume Automotive Manufacturing (LVAM), used for niche car models manufacturing, is proposed to overcome this issue. The development of a hybrid Knowledge Based (KB) System, which is a blend of KB System, Gauging Absences of Pre-requisites (GAP), and Analytic Hierarchy Process (AHP) is proposed for LVAM research. The hybrid KB/GAP/AHP System identifies all potential elements of LVAM issues throughout the development of this system. The KB System used in the LVAM analyses the gap between the existing and the benchmark organisations for an effective implementation. The novelty and differences in the current research approach emphasises the use of Knowledge Based (KB) System in the planning and designing stages by suggesting recommendations of LVAM implementation, through: a) developing the conceptual LVAM model; b) designing the KBLVAM System structure based on the conceptual LVAM model; and c) embedding Gauging Absences of Pre-requisites (GAP) analysis and Analytic Hierarchy Process (AHP) approach in the hybrid KBLVAM System. The KBLVAM Model explores five major perspectives in two stages. Planning Stage (Stage 1) consists of Manufacturer Environment Perspective (Level 0), LVAM Manufacturer Business Perspective (Level 1), and LVAM Manufacturer Resource Perspective (Level 2). Design Stage (Stage 2) consists of LVAM Manufacturer Capability ¿ Car Body Part Manufacturing Perspective (Level 3), LVAM Manufacturer Capability ¿ Competitive Priorities Perspective (Level 4), and LVAM Manufacturer Capability ¿ Lean Process Optimisation Perspective (Level 5). Each of these perspectives consists of modules and sub-modules that represent specific subjects in the LVAM development. Based on the conceptual LVAM model, all perspectives were transformed into the KBLVAM System structure, which is embedded with the GAP and AHP techniques, hence, key areas of potential improvement are recommended for each activity for LVAM implementation. In order to be able to address the real situation of LVAM environment, the research verification was conducted for two automotive manufacturers in Malaysia. Some published case studies were also used to check several modules for their validity and reliability. This research concludes that the developed KBLVAM System provides valuable decision making information and knowledge to assist LVAM practitioners to plan, design and implement LVAM in terms of business organisation, manufacturing aspects and practices. / Universiti Malaysia Pahang and Ministry of Higher Education Malaysia
239

The design and development of a knowledge-based lean six sigma maintenance system for sustainable buildings. The design and development of a hybrid Knowledge-based (KB)/Gauging Absence of Pre-requisites (GAP)/Analytic Hierarchy Process (AHP) model for implementing lean six sigma maintenance system in sustainable buildings' environment

Al Dairi, Jasim S.S. January 2017 (has links)
The complexity of sustainable building maintenance environment requires managers to define and implement appropriate quality benchmark system suitable for this function. Lean Six Sigma (LSS) is one of the most effective process improvement and optimization philosophy that maintenance organisations can implement in their environment. However, literature review has shown that 90% of failures in LSS implementations are due to lack of readiness to change, the unawareness of the required benchmark organisation capabilities, and improper control of priorities. The contribution of the current research approach is in developing a hybrid Knowledge-Based (KB)/GAP/AHP System, consisting of three stages (Planning, Designing and Implementation) and containing over 2500 KB rules. The KB System can assist the decision-makers in identifying the obstacles behind the organisation readiness to change into a benchmark LSS maintenance environment. Thus the KB System will be used to achieve benchmark standards by determining the gap existing between the current environment and the benchmark goal, and then suggest a detailed plan to overcome these hurdles in a prioritised and structured manner, thus achieving cost benefits. To ensure its consistency and reliability, the KB System was validated in three Oman-based maintenance organisations, and one published case study for a UK-based organisation. The results from the validation were positive with the System output suggesting list of top priorities and action plans for achieving benchmark LSS standards for these organisations. The research concludes that the developed KB System is a consistent and reliable methodology for assisting decision-makers in designing, planning, and implementing LSS for benchmark sustainable building maintenance.
240

Simulated Annealing-based Multilink Selection Algorithm in SDN-enabled Avionic Networks

Luong, Doanh K., Ali, Muhammad, Li, Jian-Ping, Asif, Rameez, Abdo, K. 03 November 2021 (has links)
Yes / In this paper, a novel multilink selection framework is developed for different applications with various quality of service (QoS) requirements in avionic systems, based on the multi-attribute decisionmaking model. Two metaheuristic algorithms are proposed to solve this model while optimizing the multilink selection performances. Multilink configuration and multi-homing capabilities are generally required for aircrafts operating in a heterogeneous wireless network environment. The first algorithm, called Analytic Hierarchy Process and Simulated Annealing (AHP-SA), utilises a two-phase process. In Phase one, an analytic hierarchy process (AHP) is used to choose the decision weight factors. Then, in Phase two, a simulated annealing process is applied to select suitable networks, for various service requests, based on the weights obtained from first phase. Further, to improve customer satisfaction, Simulated Annealing algorithm for Simultaneous Weights and Network Selection Optimisation (SA-SWNO) is developed, in which a simulated annealing algorithm is applied to dynamically optimise weight factors of objective functions and the request-to-network assignment matrix. Simulation results demonstrates that both proposed algorithms outperform the commonly used price-based or QoS-based network selection scheme with much higher averaged satisfaction degree and lower computational complexity. / Cockpit NetwOrk CoMmunications Environment Testing (COMET) Project under the European Commission’s Program Clean Sky2 in partnership with the European Aeronautical Industry

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