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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.
51

Layout Design of A Third Party-Logistics Centre: A Case Study

Eren, Nurdan, Sat, Yusuf Hasim January 2010 (has links)
<p>The purpose of this thesis is to develop an integrated model which involves creative and analytical features for designing a cost effective logistics centre layout on operational level, with respect to time and space utilization. Engineering methods, creative skills, simulation and multi-criteria decision making methods were integreted in the  developed model. The model has been implemented and validated in Oskarshamn Intralog, which is a sister company of Scania. After applying the model in the case company, three different layout concepts were generated based on engineering and simulation techniques. These concepts were evaluated from utilization of space, time and flexibility aspects. Furthermore, multi criteria decision making method was used to select the most cost effective layout concept among these concepts. Different aspects helped to see various effects of warehouse operations on layout design. Simulation was used as a powerful tool to test cycle time within designed concepts. Clearly it was concluded that a combination of two concepts led to reach the expected results as an optimum point among space, time utilization and flexibility which fullfilled the answer to both academical and practical problem</p> / <p><strong> </strong></p><p>Syftet med den här uppsatsen är att utveckla en integrerad modell som inbegriper kreativa och analytiska egenskaper. Modellen ska användas till att designa en kostnadseffektiv planering av anläggningen för ett logistikcentrum på en operationell nivå, med avseende på tid- och lagerplatsutnyttjande. Tekniska metoder, kreativitet, simulering, samt “multi-criteria decision making” är integrerade i modellen. Validering och implementering av modellen skedde på Oskarshamn Intralog, ett systerföretag till Scania. Efter tillämpning av modellen på fallföretaget, genererades tre olika koncept för planering av anläggningen. Koncepten utvärderades utifrån utnyttjande av plats, tid, samt flexibilitet. Dessutom har metoden “multi-criteria decision making” använts för att selektera det mest kostnadseffektiva av de tre koncepten. Olika aspekter på tid- och lagerplatsutnyttjande, samt flexibilitet bidrog till att se olika effekter på lagerhantering. Simuleringar genomfördes för att testa cykeltiden i de utvecklade koncepten. Slutsatsen är att en kombination av två koncept ledde till det förväntade resultatet; en optimal punkt för tid- och lagerplatsutnyttjande, samt flexibilitet, vilket uppfyller svar till de akademiska och praktiska problemen</p>
52

Layout Design of A Third Party-Logistics Centre: A Case Study

Eren, Nurdan, Sat, Yusuf Hasim January 2010 (has links)
The purpose of this thesis is to develop an integrated model which involves creative and analytical features for designing a cost effective logistics centre layout on operational level, with respect to time and space utilization. Engineering methods, creative skills, simulation and multi-criteria decision making methods were integreted in the  developed model. The model has been implemented and validated in Oskarshamn Intralog, which is a sister company of Scania. After applying the model in the case company, three different layout concepts were generated based on engineering and simulation techniques. These concepts were evaluated from utilization of space, time and flexibility aspects. Furthermore, multi criteria decision making method was used to select the most cost effective layout concept among these concepts. Different aspects helped to see various effects of warehouse operations on layout design. Simulation was used as a powerful tool to test cycle time within designed concepts. Clearly it was concluded that a combination of two concepts led to reach the expected results as an optimum point among space, time utilization and flexibility which fullfilled the answer to both academical and practical problem / Syftet med den här uppsatsen är att utveckla en integrerad modell som inbegriper kreativa och analytiska egenskaper. Modellen ska användas till att designa en kostnadseffektiv planering av anläggningen för ett logistikcentrum på en operationell nivå, med avseende på tid- och lagerplatsutnyttjande. Tekniska metoder, kreativitet, simulering, samt “multi-criteria decision making” är integrerade i modellen. Validering och implementering av modellen skedde på Oskarshamn Intralog, ett systerföretag till Scania. Efter tillämpning av modellen på fallföretaget, genererades tre olika koncept för planering av anläggningen. Koncepten utvärderades utifrån utnyttjande av plats, tid, samt flexibilitet. Dessutom har metoden “multi-criteria decision making” använts för att selektera det mest kostnadseffektiva av de tre koncepten. Olika aspekter på tid- och lagerplatsutnyttjande, samt flexibilitet bidrog till att se olika effekter på lagerhantering. Simuleringar genomfördes för att testa cykeltiden i de utvecklade koncepten. Slutsatsen är att en kombination av två koncept ledde till det förväntade resultatet; en optimal punkt för tid- och lagerplatsutnyttjande, samt flexibilitet, vilket uppfyller svar till de akademiska och praktiska problemen
53

Metrics for security activities assisted by argumentative logic / Métriques pour le déclenchement des évènements de sécurité assistées par la logique argumentative

Bouyahia, Tarek 29 March 2017 (has links)
L'accroissement et la diversification des services offerts par les systèmes informatiques modernes rendent la tâche de sécuriser ces systèmes encore plus complexe. D'une part, l'évolution du nombre de services système accroît le nombre des vulnérabilités qui peuvent être exploitées par des attaquants afin d'atteindre certains objectifs d'intrusion. D'autre part, un système de sécurité moderne doit assurer un certain niveau de performance et de qualité de service tout en maintenant l'état de sécurité. Ainsi, les systèmes de sécurité modernes doivent tenir compte des exigences de l'utilisateur au cours du processus de sécurité. En outre, la réaction dans des contextes critiques contre une attaque après son exécution ne peut pas toujours remédier à ses effets néfastes. Dans certains cas, il est essentiel que le système de sécurité soit en avance de phase par rapport à l'attaquant et de prendre les mesures nécessaires pour l'empêcher d'atteindre son objectif d'intrusion. Nous soutenons dans cette thèse que le processus de sécurité doit suivre un raisonnement intelligent qui permet au système de prévoir les attaques qui peuvent se produire par corrélation à une alerte détectée et d'appliquer les meilleures contre-mesures possibles. Nous proposons une approche qui génère des scénarios potentiels d'attaque qui correspondent à une alerte détectée. Ensuite, nous nous concentrons sur le processus de génération d'un ensemble approprié de contre-mesures contre les scénarios d'attaque générés. Un ensemble généré des contre-mesures est considéré comme approprié dans l'approche proposée s'il présente un ensemble cohérent et il satisfait les exigences de l'administrateur de sécurité (par exemple, la disponibilité). Nous soutenons dans cette thèse que le processus de réaction peut être considéré comme un débat entre deux agents. D'un côté, l'attaquant choisit ses arguments comme étant un ensemble d'actions pour essayer d'atteindre un objectif d'intrusion, et de l'autre côté l'agent défendant la cible choisit ses arguments comme étant un ensemble de contre-mesures pour bloquer la progression de l'attaquant ou atténuer les effets de l'attaque. D'autre part, nous proposons une approche basée sur une méthode d'aide à la décision multicritère. Cette approche assiste l'administrateur de sécurité lors de la sélection des contre-mesures parmi l'ensemble approprié des contre-mesures générées à partir de la première approche. Le processus d'assistance est basé sur l'historique des décisions de l'administrateur de sécurité. Cette approche permet également de sélectionner automatiquement des contre-mesures appropriées lorsque l'administrateur de sécurité est dans l'incapacité de les sélectionner (par exemple, en dehors des heures de travail, par manque de connaissances sur l'attaque). Enfin, notre approche est implémentée et testée dans le cadre des systèmes automobiles / The growth and diversity of services offered by modern systems make the task of securing these systems a complex exercise. On the one hand, the evolution of the number of system services increases the risk of causing vulnerabilities. These vulnerabilities can be exploited by malicious users to reach some intrusion objectives. On the other hand, the most recent competitive systems are those that ensure a certain level of performance and quality of service while maintaining the safety state. Thus, modern security systems must consider the user requirements during the security process.In addition, reacting in critical contexts against an attack after its execution can not always mitigate the adverse effects of the attack. In these cases, security systems should be in a phase ahead of the attacker in order to take necessary measures to prevent him/her from reaching his/her intrusion objective. To address those problems, we argue in this thesis that the reaction process must follow a smart reasoning. This reasoning allows the system, according to a detected attack, to preview the related attacks that may occur and to apply the best possible countermeasures. On the one hand, we propose an approach that generates potential attack scenarios given a detected alert. Then, we focus on the generation process of an appropriate set of countermeasures against attack scenarios generated among all system responses defined for the system. A generated set of countermeasures is considered as appropriate in the proposed approach if it presents a coherent set (i.e., it does not contain conflictual countermeasures) and it satisfies security administrator requirements (e.g., performance, availability). We argue in this thesis that the reaction process can be seen as two agents arguing against each other. On one side the attacker chooses his arguments as a set of actions to try to reach an intrusion objective, and on the other side the agent defending the target chooses his arguments as a set of countermeasures to block the attacker's progress or mitigate the attack effects. On the other hand, we propose an approach based on a recommender system using Multi-Criteria Decision Making (MCDM) method. This approach assists security administrators while selecting countermeasures among the appropriate set of countermeasures generated from the first approach. The assistance process is based on the security administrator decisions historic. This approach permits also, to automatically select appropriate system responses in critical cases where the security administrator is unable to select them (e.g., outside working hours, lack of knowledge about the ongoing attack). Finally, our approaches are implemented and tested in the automotive system use case to ensure that our approaches implementation successfully responded to real-time constraints.
54

Systematising early evaluation of potential acquisition targets of PE investments : A research model for decision making influenced by information asymmetry / Systematisering av tidig utvärdering av potentiella förvärvsmöjligheter för PE-investeringar : En forskningsmodell för beslutsfattande påverkat av informationsasymmetri

Halvord, Erik, Wassén Fagerberg, Maja January 2019 (has links)
Acquisitions are a major part of the growth and evolution of companies within varying markets. They are conducted under various circumstances with differing aims and rationales, and for different purposes. This thesis focuses on acquisitions carried out by serial investors acting in a private equity market. These acquisitions are characterised by a highly competitive nature, where access to a large pipeline of potential targets is believed to be a key success factor. As such, deal origination and sourcing of potential targets become important factors to facilitate a high-paced deal flow. Earlier research suggests that this is well researched with regards to venture capital, but to a large extent lacking within private equity. This thesis analyses and discusses the possibility of systematising early evaluation of potential acquisition targets within private equity. The aim is to suggest a framework that may be utilised, consisting of the criteria deemed important for early evaluation. Through utilising multi criteria decision making, the framework allows for a relative importance between criteria to contribute to assessment, while fuzzy set theory allows for a degree of uncertainty to be incorporated. This thesis is conducted through data collection from a number of professionals within private equity, selected from a non-probability sample. Semi-structured interviews and a 3 pairwise comparison is utilised to allow for analysis and discussion with regards to earlier research and theory, while allowing for comparison between respondents. The results of the thesis indicate that utilising a framework for early evaluation of potential targets may be beneficial. The key dimensions to consider are financial, commercial and market capabilities. However, the criteria constituting the dimensions may be firm or industry specific. / Förvärv är en viktig del av tillväxten och utvecklingen av företag i en rad olika marknader. De genomförs under varierande förutsättningar med olika mål och avsikter, och med olika syften. Denna uppsats fokuserar på förvärv utförda av serieinvesterare på en riskkapitalsmarknad. Dessa förvärv karaktäriseras av en konkurrensutsatt marknad, där tillgång till en bred pipeline av potentiella förvärvsmöjligheter förväntas vara en viktig framgångsfaktor. Således är hantering av leadsgenerering och sourcing av möjliga förvärvsobjekt viktiga faktorer för att främja ett aktivt förvärvsflöde. Tidigare forskning tyder på att detta är ett välutforskat område inom venture capital, men saknas i stor utsträckning inom riskkapital. Denna uppsats analyserar och diskuterar möjligheten att systematisera tidig utvärdering av potentiella förvärvsobjekt inom riskkapital. Avsikten är att föreslå ett ramverk som kan användas, bestående av de kriteria som anses viktiga vid tidig utvärdering. Genom att använda multi criteria decision making möjliggör ramverket en relativ betydelse mellan kriterier att påverka bedömningen, medan fuzzy set-teori möjliggör för en grad av osäkerhet att inkorporeras. Denna uppsats utförs genom datainsamling från ett antal yrkesverksamma inom riskkapital, utvalda från en icke-sannolikhetsprovtagning. Semi-strukturerade intervjuer och en parvis 5 jämförelse används för analys och diskussion i relation till tidigare forskning och teori, och tillåter även jämförelse mellan svarande. Resultaten av denna uppsats indikerar att användande av ett ramverk för tidig utvärdering av potentiella förvärvsobjekt kan vara positiv. De viktigaste dimensionerna att ta i beaktning är finansiella, kommersiella och marknadsmässiga förmågor. Kriterierna som utgör dessa dimensioner kan dock vara bolags- eller industrispecifika.
55

Development of a multi-criteria approach for the selection of sustainable materials for building projects

Akadiri, Oluwole Peter January 2011 (has links)
Construction activity is known to have a major impact on the environment and is a major consumer of a wide range of naturally occurring and synthesized resources. Despite the recognition that environmental issues are important to the survival of the construction industry, the industry continues to degrade the environment, exploiting resources and generating waste, and is slow to change its conventional practices to incorporate environmental matters as part of its decision making process. With increased awareness and knowledge of these impacts, efforts are being made to avoid these adverse effects and to work towards impact mitigation. Among these is sustainable building material selection. Building material selection is an important issue in building design and construction decision-making and environmental issues need to be incorporated into the evaluation process. The research reported in this thesis was initiated to address these issues in the UK, towards developing an assessment model for incorporating sustainability into building material selection process. A questionnaire survey was conducted to investigate the level of awareness, knowledge and implementation of sustainable practices among architects and designers and how this impacts on their design decisions. To facilitate the implementation of sustainable practices into building material selection, a set of sustainable assessment criteria (SAC) for modeling and evaluating sustainability performance of building materials was developed. Building material can be assessed using an index system that combines the principal criteria of sustainable development. The derived criteria were assessed and aggregated into a composite sustainability index using the Analytical Hierarchy Process (AHP) technique which has been praised for its ability to incorporate both objective and subjective considerations in the decision process. The development of a sustainability index is a way of supporting decision makers faced with making numerous and sometimes conflicting evaluation as with building material selection. The methodology adopted in undertaking this research was the mixed method approach involving a detailed review of the relevant literature, followed by an industry-wide survey of UK architects and designers. Following this, case study was conducted to collect data for sustainability criteria used in the assessment model. The data collected were analyzed, with the aid of SPSS, Excel and expert choice software using a variety of statistical methods including descriptive statistics analysis, relative index analysis, Kendall’s concordance and factor analysis. The key finding was the existing gap between awareness and implementation of sustainable construction practices, which has led to failure of realizing the benefits of a sustainable approach to construction. The study showed a discrepancy between what architects and designers claim to be convinced about, and knowledgeable in, and their commitment and practices; they seem to be unable to translate their environmental awareness and knowledge into appropriate design decisions and are in need of a decision support system that can aid the incorporation of sustainability into building design. The model developed satisfy this gap and was validated by application to a roof covering material selection decision process for a case study building project by means of experts’ review via a survey and the findings obtained suggest that the model is valuable and suitable for use in practice. Finally, areas for further research were identified.
56

An efficient ranking analysis in multi-criteria decision making

Jaini, Nor January 2017 (has links)
This study is conducted with the aims to develop a new ranking method for multi-criteria decision making problem with conflicting criteria. Such a problem has a set of Pareto solutions, where the act of improving a value of one solution will result in depreciating some of the others. Thus, in this type of problem, there is no unique solution. However, out of many available options, the Decision Maker eventually has to choose only one solution. With this problem as the motivation, the current study develops a compromise ranking algorithm, namely a trade-off ranking method. The trade-off ranking method able to give a trade-off solution with the least compromise compared to other choices as the best solution. The properties of the algorithm are studied in the thesis on several test cases. The proposed method is compared against several multi-criteria decision making methods with ranking based on the distance measure, which are the TOPSIS, relative distance and VIKOR. The sensitivity analysis and uncertainty test are carried out to examine the methods robustness. A critical criteria analysis is also done to test for the most critical criterion in a multi-criteria problem. The decision making method is considered further in a fuzzy environment problem where the fuzzy trade-off ranking is developed and compared against existing fuzzy decision making methods.
57

Integrisani model vrednovanja dobavljača u lancima snabdevanja / An integrated model for supplier evaluation in supply chains

Stević Željko 12 April 2018 (has links)
<p>U ovom radu predložen je model za vrednovanje i izbor dobavljača koji je razmatran u vi&scaron;e od deset različitih proizvodnih oblasti. Model se sastoji od dvadeset kvantitavnih i kvalitativnih kriterijuma koji su primenom fuzzy AHP (Analitičko Hijerarhijski Proces) metode, a na osnovu ocenjivanja menadžera proizvodnih kompanija smanjeni na ukupno devet. Verifikacija datog modela predstavljena je kroz vrednovanje i izbor dobavljača u tri kompanije koje se bave različitom delatno&scaron;ću. Pored doprinosa koji se ogleda u primenjivosti razvijenog modela u različitim lancima snabdevanja, veliki doprinos ovog rada je razvoj novih pristupa u oblasti vi&scaron;ekriterijumskog odlučivanja koji može biti primenjen u svim lancima snabdevanja, naročito u procesima u kojima vladaju neizvesnosti i nejasnoće &scaron;to je detaljno obja&scaron;njeno kroz rad.</p> / <p>In this paper, a model for evaluation and supplier selection has been<br />proposed, which has been considered in more than ten different production<br />areas. The model consists of twenty quantitative and qualitative criteria which<br />are reduced to a total of nine by the application of the fuzzy AHP (Analytic<br />Hierarchy Process) method and the assessment of managers in production<br />companies. The verification of the given model is presented through the<br />evaluation and supplier selection in three companies that deal with different<br />activities. In addition to the contribution reflected in the applicability of the<br />developed model in various supply chains, the great contribution of this<br />paper is the development of new approaches in the field of multi-criteria<br />decision making that can be applied in all supply chains, especially in<br />processes that are subject to uncertainty and vagueness, which is explained<br />in detail through the work.</p>
58

A Sensitivity Analysis of a Heuristic Model used for the Placement Allocation of Utilities in Transportation Right-of-Way Corridors

Christian, Steve Clarence 08 November 2004 (has links)
The requirements for public utility systems in the United States of America have grown enormously over the years triggering a tremendous shortage for space available to public utilities on and within transportation right-of-ways (ROW). Overcrowding and improper location of utilities has resulted in problems such as, damage to infrastructure, traffic accidents and, interruption of service to customers. The project titled, "Optimal Placement of Utilities within FDOT Right-of-Way", sponsored by the Florida Department of Transportation (FDOT), and currently being investigated at the University of South Florida, presents a decision-making heuristic aimed at developing a better utility placement allocation system (Kranc et. al) [6]. Working in accordance with the guidelines of safety, relocation, and clearance for utility placement set by the American Association of State Highway and Transportation Officials organization (AASHTO), the heuristic finds suitable locations for the utilities in ROW corridors. However, a model being used to advocate a practice having large social and economical impacts is more likely to play the role of generic evidence in a trial, whose weight must ultimately be established by a 'jury'. The question being addressed to the system must be scrutinized carefully, and the formal structure updated iteratively until it proves capable of providing an answer to the given question. A good sensitivity analysis can provide this generic quality assurance to the model and help demonstrate the worthiness of the model itself. This thesis is a quantitative and qualitative sensitivity analysis of the abovementioned heuristic. The analysis is conducted in two parts, 1. The 'Model Factor Sensitivity Analysis', with the objective of assessing the uncertainties associated with the modeling of the heuristic. This analysis focuses primarily on providing an evaluation of the confidence in the heuristic and its predictions by analyzing the influences that variations in the input factors have on the outputs of the utility cost assessment models and the final output of the heuristic itself. Variance based sensitivity indices derived from Sobol' sensitivity indices [42] are used here for this purpose. 2. The 'Model Output Evaluation and Enhancement' study, which initially focuses on understanding / evaluating the complexities of the discrete step, cost optimization procedure used in the heuristic and later, based on certain observed shortcomings and problems develops an enhancement, the Ideal Configuration Selector (ICS) to be implemented with the heuristic. The ICS addresses all the problems of the heuristic with the help of experimental speedup, positional sensitivity and refinement tools and employs a multi criterion evaluation technique for utility configuration assessment to provide substantiation to the outputs determined by the heuristic.
59

Gis-based Site Selection Approach For Wind And Solar Energy Systems: A Case Study From Western Turkey

Aydin, Nazli Yonca 01 July 2009 (has links) (PDF)
Many countries around the world integrated Renewable Energy Systems (RES) in their future energy plans in order to reduce negative impacts of fossil fuel consumption on the environment. However, RES may as well cause various environmental problems which are mostly related with the geographic locations of these facilities. The aim of this thesis is to create a Geographic Information System-based methodology for evaluating alternative locations for wind, solar and hybrid power plants by using fuzzy multi-criteria decision making. Environmental objectives and economical feasibility criteria for wind and solar systems are identified through Turkish legislations, previous studies, and interviews with General Directorate of Electrical Power Resources Survey and Development. Individual satisfaction degrees for each alternative location with respect to the identified environmental objectives and economical feasibility criteria are calculated using fuzzy set theory tools. Then these individual satisfaction degrees are aggregated into overall performance indexes which are used to determine priority maps for wind and solar energy generation facilities. Finally, maps of priority sites for wind and solar energy systems are overlaid to identify suitable locations for hybrid wind-solar energy systems. The proposed methodology is applied on a case study area composed of USak, Aydin, Denizli, Mugla, and Burdur provinces.
60

Interval Priority Weight Generation From Interval Comparison Matrices In Analytic Hierarchy Process

Ozturk, Ufuk 01 September 2009 (has links) (PDF)
In this study, for the well-known Analytic Hierarchy Process (AHP) method a new approach to interval priority weight generation from interval comparison matrix is proposed. This method can be used for both inconsistent and consistent matrices. Also for the problems having more than two hierarchical levels a synthesizing heuristic is presented. The performances of the methods, interval generation and synthesizing, are compared with the methods that are already available in the literature on randomly generated matrices.

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