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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.
621

The sensitivity analysis of the quantitative multiple attribute decision making methods / Kiekybinių daugiatikslių sprendimo priėmimo metodų jautrumo analizė

Simanavičienė, Rūta 27 February 2012 (has links)
The problems, associated with sensitivity of quantitative multiattribute decision-making methods to the initial data and the reliability of the decision obtained by using these methods, are considered in the presented dissertaition. The methods discussed are applied to solving decision-making problems, consisting in the selection of one alternative out of the available several options, when a decision-making person seeks to achieve a number of aims, rather than a single aim, and the alternatives are evaluated based on a set of attribute, which may be conflicting. The research object is sensitivity of the popular quantitative multiattribute decision-making methods: TOPSIS, SAW and COPRAS to the initial data errors. The initial data inaccuracy may be caused by the errors made by a person, entering the data. The estimates of the alternatives may have some errors, which are not taken into account, when the considered methods are used with these data. The analysis of the related works has shown that there are methods for evaluating sensitivity with respect to one attribute, based on varying the significance values, such as the method of the most critical criterion (Triantaphyllou 2000) and to many attributes - Tornado diagram. However, these methods do not show either the errors of solution results or the reliability level of the result obtained. The main aim of the dissertation is the evaluation of the stochastic nature of multiattribute decision-making methods, based on... [to full text] / Disertacijoje nagrinėjamas kiekybinių daugiatikslių sprendimo priėmimo metodų jautrumas ir juos taikant gautų sprendimų patikimumas. Daugiatiksliai sprendimo priėmimo metodai taikomi sprendimo priėmimo uždaviniuose, renkantis vieną alternatyvą iš keleto galimų, kai sprendimą priimantis asmuo siekia ne vieno, o kelių tikslų, o alternatyvos vertinamos pagal daugelį efektyvumo rodiklių, kurie gali būti tarpusavyje prieštaraujantys (pvz. kainos ir naudos rodikliai). Pagrindinis tyrimo objektas yra metodų TOPSIS, SAW ir COPRAS jautrumas pradinių duomenų netikslumams. Duomenų netikslumai galimi dėl pradinių duomenų reikšmes nustatančio asmens padarytų klaidų. Tokiu atveju, kai taikant minėtus metodus, alternatyvų vertinimui naudojami pradiniais duomenys turintys tam tikras paklaidas, alternatyvų vertinimai gali būti su paklaidomis, kurios, taikant šiuos metodus, nebėra vertinamos. Išanalizavus susijusius darbus, nustatyta, jog yra metodų, skirtų vertinti sprendimo jautrumą vieno rodiklio atžvilgiu, keičiant reikšmingumo reikšmes, tai - kritiškiausio kriterijaus metodas (Triantaphyllou 2000) ir daugelio rodiklių atžvilgiu - Tornado diagrama. Tačiau šie metodai nepateikia nei sprendimo rezultatų paklaidų, nei rezultato patikimumo laipsnio. Pagrindinis disertacijos tikslas – įvertinti daugiatikslių, kiekybiniais matavimais pagrįstų sprendimo priėmimo metodų stochastiką. Sukurtų metodų taikymo sritis – sprendimo paramos sistemų projektavimas, sprendimų patikimumo ir sprendimų priėmimo... [toliau žr. visą tekstą]
622

Effect of computer based training and testing on structured on–the–job training programs / M.A. Agbogo

Agbogo, Adakole Michael January 2010 (has links)
Human capital is the only resource within an organisation that can learn. Developing high levels of competence in employees is one of the most challenging issues in organisations. Off–the–Job training programs either miss the mark or are too far away from the performance setting to have the desired impact on employee competence. Studies have shown that unstructured On–the–Job Training (OJT) leads to increased error rate, lower productivity and decreased training efficiency, compared to structured On–the–Job Training(S–OJT). The proven efficiency and effectiveness of S–OJT make it especially suitable to meet this challenge. Though S–OJT has been around for a while there has not been a proper integration of technology into the process. Every training approach, including S–OJT, is merely a means to an end, not an end in itself. The use of S–OJT helps to develop consistent appropriate levels of employee competence. When employees have these competencies e.g. better knowledge of the production processes, they can increase productivity, complete projects on time, lower defect rates, or achieve other outcomes of importance. These are the outcomes that matter to the organisation and the effectiveness of S–OJT should be judged from this perspective. Researchers have consistently found that one way to improve learners' success is to increase the frequency of exams. Classes meet for a set number of times. An instructor's decision to give more exams typically means that students have less time for learning activities during class meetings. How then can one have the best of both worlds, increasing the number of assessments and at the same time having enough time for learning activities? This can only be accomplished by integrating computer–based assessment into S–OJT programs. Computer–based testing and training can provide flexibility, instant feedback, an individualised assessment and eventually lower costs than traditional written examinations. Computerised results create opportunities for teaching and assessment to be integrated more than ever before and allow for retesting students, measuring growth and linking assessment to instruction. This research aims to evaluate the effectiveness of integrating computer–based testing and training into S–OJT programs using the Air Separation unit of Sasol Synfuels as a case study. The null hypothesis is used to investigate the draw backs of OJT and S–OJT programs. A framework is also developed for the effective integration of CBT into S–OJT programs. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2011.
623

Effect of computer based training and testing on structured on–the–job training programs / M.A. Agbogo

Agbogo, Adakole Michael January 2010 (has links)
Human capital is the only resource within an organisation that can learn. Developing high levels of competence in employees is one of the most challenging issues in organisations. Off–the–Job training programs either miss the mark or are too far away from the performance setting to have the desired impact on employee competence. Studies have shown that unstructured On–the–Job Training (OJT) leads to increased error rate, lower productivity and decreased training efficiency, compared to structured On–the–Job Training(S–OJT). The proven efficiency and effectiveness of S–OJT make it especially suitable to meet this challenge. Though S–OJT has been around for a while there has not been a proper integration of technology into the process. Every training approach, including S–OJT, is merely a means to an end, not an end in itself. The use of S–OJT helps to develop consistent appropriate levels of employee competence. When employees have these competencies e.g. better knowledge of the production processes, they can increase productivity, complete projects on time, lower defect rates, or achieve other outcomes of importance. These are the outcomes that matter to the organisation and the effectiveness of S–OJT should be judged from this perspective. Researchers have consistently found that one way to improve learners' success is to increase the frequency of exams. Classes meet for a set number of times. An instructor's decision to give more exams typically means that students have less time for learning activities during class meetings. How then can one have the best of both worlds, increasing the number of assessments and at the same time having enough time for learning activities? This can only be accomplished by integrating computer–based assessment into S–OJT programs. Computer–based testing and training can provide flexibility, instant feedback, an individualised assessment and eventually lower costs than traditional written examinations. Computerised results create opportunities for teaching and assessment to be integrated more than ever before and allow for retesting students, measuring growth and linking assessment to instruction. This research aims to evaluate the effectiveness of integrating computer–based testing and training into S–OJT programs using the Air Separation unit of Sasol Synfuels as a case study. The null hypothesis is used to investigate the draw backs of OJT and S–OJT programs. A framework is also developed for the effective integration of CBT into S–OJT programs. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2011.
624

A Complex Co-Evolutionary Systems Approach to the Management of Sustainable Grasslands: A Case Study in Mexico

Martinez-Garcia, Alejandro N. Unknown Date (has links)
The complex co-evolutionary systems approach (CCeSA) provides a well-suited framework for analysing agricultural systems, serving as a bridge between biophysical and socioeconomic sciences, allowing for the explanation of phenomena, and for the use of metaphors for thinking and action. By studying agricultural systems as self-generated, hierarchical, complex co-evolutionary farming systems (CCeFSs), one can investigate the interconnections between the elements that constitute CCeFSs, along with the relationships between CCeFSs and other systems, as a fundamental step to understanding sustainability as an emergent property of the system. CCeFSs are defined as human activity systems emerging from the purposes, gestalt, mental models, history and weltanschauung of the farm manager, and from his dynamic co-evolution with the environment while managing the resources at his hand to achieve his own multiple, conflicting, dynamic, semi-structured and constrained purposes. A sustainable CCeFS is described as one that exhibits both enough fitness to achieve its multiple, dynamic, constrained, semi-structured, and often incommensurable and conflicting purposes while performing above threshold values for failure, and enough flexibility to dynamically co-evolve with its changing biophysical and socioeconomic environment for a given future period. Fitness and flexibility are essential features of sustainable CCeFSs because they describe the systems' dynamic capacity to explore and exploit its dynamic phase space while co-evolving with it. This implies that a sustainable CCeFS is conceived as a set of dynamic, co-evolutionary processes, contrasting with the standard view of sustainability as an equilibrium or steady state. Achieving sustainable CCeFSs is a semi-structured, constrained, multi-objective, and dynamic optimisation management problem with an intractable search phase space, that can be solved within the CCeSA with the help of a multi-objective co-evolutionary optimisation tool. Carnico-ICSPEA2, a Co-Evolutionary Navigator (CoEvoNav) used as a CCeSA's tool for harnessing the complexity of the CCeFS of interest and its environment towards sustainability, is introduced. The software was designed by its end-user - the farm manager and author of this thesis - as an aid for the analysis and optimisation of the "San Francisco" ranch, a beef cattle enterprise running on temperate pastures and fodder crops in the central plateau of Mexico. By combining a non-linear simulator and a multi-objective evolutionary algorithm with a deterministic and stochastic framework, the CoEvoNav imitates the co-evolutionary pattern of the CCeFS of interest. As such, the software was used by the farm manager to "navigate" through his CCeFS's co-evolutionary phase space towards achieving sustainability at farm level. The ultimate goal was to enhance the farm manager's decision-making process and co-evolutionary skills, through an increased understanding of his system, the co-evolutionary process between his mental models, the CCeFS, and the CoEvoNav, and the continuous discovery of new, improved sets of heuristics. An overview of the methodological, theoretical and philosophical framework of the thesis is introduced. Also, a survey of the Mexican economy, its agricultural sector, and a statistical review of the Mexican beef industry are presented. Concepts such as modern agriculture, the reductionist approach to agricultural research, models, the system's environment, sustainability, conventional and sustainable agriculture, complexity, evolution, simulators, and multi-objective optimization tools are extensively reviewed. Issues concerning the impossibility of predicting the long-term, detailed future behaviour of CCeFSs, along with the use of simulators as decision support tools in the quest for sustainable CCeFSs, are discussed. The rationale behind the simulator used for this study, along with that of the multi-objective evolutionary tools used as the makeup of Carnico-ICSPEA2, are explained. A description of the "San Francisco" ranch, its key on-farm sustainability indicators in the form of objective functions, constraints, and decision variables, and the semi-structured, multi-objective, dynamic, constrained management problem posed by the farm manager's planned introduction of a herd of bulls for fattening as a way to increase the fitness of his CCeFS via a better management of the system's feed surpluses and the acquisition of a new pick-up truck are described as a case study. The tested scenario and the experimental design for the simulations are presented as well. Results from using the CoEvoNav as the farm manager's extended phenotype to solve his multi-objective optimisation problem are described, along with the implications for the management and sustainability of the CCeFS. Finally, the approach and tools developed are evaluated, and the progress made in relation to methodological, theoretical, philosophical and conceptual notions is reviewed along with some future topics for research.
625

Multi-agent decision support system in avionics : improving maintenance and reliability predictions in an intelligent environment

Haider, Kamal January 2009 (has links)
Safety of the airborne platforms rests heavily on the way they are maintained. This maintenance includes repairs and testing, to reduce platform down time. Maintenance is performed using generic and specific test equipment within the existing maintenance management system (MMS). This thesis reports the work undertaken to improve maintainability and availability of avionics systems using an intelligent decision support system (IDSS). In order to understand the shortcomings of the existing system, the prevalent practices and methodologies are researched. This research thesis reports the development and implementation of an IDSS and the significant improvements made by this IDSS by integrating autonomous and independent information sources by employing a multi-agent system (MAS). Data mining techniques and intelligence agents (IA) are employed to create an expert system. The developed IDSS successfully demonstrates its ability to integrate and collate the available information and convert into valuable knowledge. Using this knowledge, the IDSS is able to generate interpreted alerts, warnings and recommendations thereby reasonably improving platform maintainability and availability. All facets of integrated logistics support (ILS) are considered to create a holistic picture. As the system ages, the IDSS also matures to assist managers and maintainers in making informed decisions about the platform, the unit under test (UUT) and even the environment that supports the platform.
626

Infective endocarditis : aspects of pathophysiology, epidemiology, management and prognosis /

Ekdahl, Christer, January 2008 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 6 uppsatser.
627

A methodology to aid in appropriate forest technology decision-making for developing countries

Grobbelaar, Frederik Russouw 03 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Grobbelaar, F.R. 2000. A methodology to aid in appropriate technology decision-making for developing countries. M.Sc thesis. University of Stellenbosch. In the process of selecting what we believe to be suitable technology for timber harvesting and transport, economics are usually the determining factor, whether in the form of capital investment or personnel cost. Internationally we see a move towards mechanisation in forestry for various reasons: e.g., high wages, labour shortage, and occupational safety. The realities of South Africa highlights other issues requiring attention: e.g., high unemployment, skills' shortage, global competition, rampant AIDS pandemic, and a poor safety and security record. This should focus our attention on finding local solutions to the problem of finding suitable or appropriate technology to support South Africa's quest for sustainable development. This thesis attempts to establish a methodology for the objective evaluation of alternative technologies for a specific timber harvesting situation, considering the economic, social and environmental implications. / AFRIKAANSE OPSOMMING: Grobbelaar, F.R. 2000. A methodology to aid in appropriate technology decisionmaking for developing countries. M.Sc tesis. Universiteit van Stellenbosch. Tydens die keuse van sogenaamde toepaslike tegnologie vir houtinoesting en -vervoer is ekonomie meestal die deurslaggewende faktor, hetsy verteenwoordig deur kapitaal belegging of personeelkoste. Internasionaal is daar tans In neiging na meganisasie in bosbou vir In verskeidenheid redes: bv., hoë arbeidskoste, arbeidtekort, en beroepsveiligheid. Die werklikhede van Suid-Afrika beklemtoon egter ander sake wat daadwerklike optrede vereis: nl., hoë werkloosheid, gebrek aan vaardighede, internasionale mededinging, ernstige VIGS pandemie, en In swak veiligheid-en sekuriteit rekord. Dit behoort ons aandag te fokus op die vind van plaaslike oplossings tot die probleem met die keuse van geskikte of toepaslike tegnologie ter bevordering van Suid Afrika se strewe na volhoubare ontwikkeling. Hierdie tesis poog om In metodiek te ontwikkel vir die objektiewe beoordeling van alternatiewe tegnologieë vir houtinoesting binne bepaalde omstandighede, met inagneming van ekonomiese, sosiale en omgewings implikasies.
628

Spatial decision support system for hydrogeological studies in Table Mountain Group Aquifers, Western Cape Province, South Africa

Mlisa, Andiswa 12 1900 (has links)
Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2007. / The Western Cape province of South Africa is a water scarce area with a Mediterranean climate. The majority of rainfall occurs in the cold winter months and the area experiences hot and dry summers. Studies done to investigate various water supply and water demand management options for the City of Cape Town, concluded that the Table Mountain Group (TMG) aquifer has the potential of yielding high volumes (estimated at 70Mm3/a) of good quality water, but that further research about this source as a potential augmentation supply to the City of Cape Town was necessary before extraction could commence. The aim of the study is to develop a spatial decision support system (SDSS) to be used by a hydrogeology project team, which includes hydrogeologists, environmentalists, ecologists, engineers and other stakeholders. The Table Mountain Group Aquifer (TMGA) SDSS is meant to be a decision support tool, but should also raise awareness about the use of spatial data and information and its capabilities for earth science and other multidisciplinary applications. By means of team discussions and interviews data, spatial analysis and data manipulation requirements were determined. Based on these requirements, four spatial analysis tools were developed. The spatial tool named “Borehole Analysis” analyses stratigraphic information obtained from existing boreholes and hydrogeological point data. The tool determines what groundwater use and monitoring has been undertaken in the area of interest. The “Topographic Analysis” tool identifies any topographical (e.g. rivers) and cadastral (e.g. farm boundaries) data within a certain distance from a possible borehole site. The “Sensitive Area Analysis” tool addresses queries with respect to sensitive areas, such as wetlands, statutory protected areas and private nature reserves. The “Image Classification” tool gives the team members an opportunity to use band ratios during image interpretation. The TMGA SDSS was developed using TNTmips v70, Extensible Markup Language (XML) and Spatial Manipulation Language (SML) and can be run on TNTAtlas v70, which is a free software. The TMGA SDSS enables the team members to have equal and ready access to data acquired by other members. This was found to support intra- and interdisciplinary conversation and facilitate understanding of how the data is being (or could be) used. It also contributes to levels of confidence in decision-making and supports a holistic approach to project design and implementation. Keywords: decision-making, geographic information system (GIS), spatial decision support systems (SDSS), spatial manipulation language (SML)
629

An?lise de desempenho de vendas em telecomunica??es utilizando t?cnicas de minera??o de dados / Analysis of business development in telecommunication using data minig techniques

Mattozo, Te?filo Camara 22 November 2007 (has links)
Made available in DSpace on 2014-12-17T14:52:36Z (GMT). No. of bitstreams: 1 TeofiloCM.pdf: 1145688 bytes, checksum: d9ef0be6d9fb3c2958916ee42bdb507a (MD5) Previous issue date: 2007-11-22 / Nowadays, telecommunications is one of the most dynamic and strategic areas in the world. Organizations are always seeking to find new management practices within an ever increasing competitive environment where resources are getting scarce. In this scenario, data obtained from business and corporate processes have even greater importance, although this data is not yet adequately explored. Knowledge Discovery in Databases (KDD) appears then, as an option to allow the study of complex problems in different areas of management. This work proposes both a systematization of KDD activities using concepts from different methodologies, such as CRISP-DM, SEMMA and FAYYAD approaches and a study concerning the viability of multivariate regression analysis models to explain corporative telecommunications sales using performance indicators. Thus, statistical methods were outlined to analyze the effects of such indicators on the behavior of business productivity. According to business and standard statistical analysis, equations were defined and fit to their respective determination coefficients. Tests of hypotheses were also conducted on parameters with the purpose of validating the regression models. The results show that there is a relationship between these development indicators and the amount of sales / Telecomunica??es ? uma das mais din?micas e estrat?gicas ?reas no mundo atual. H? constante necessidade das organiza??es buscarem novas formas de gerenciamento, em um ambiente cada vez mais competitivo e com recursos cada vez menores. A exist?ncia de bases de dados nas empresas passou a ter maior import?ncia. Na grande maioria dos casos, dados n?o s?o ainda explorados adequadamente. T?cnicas de Descoberta de Conhecimento em Bases de Dados (DCBD) surgem como alternativas, permitindo o estudo de problemas complexos, sendo cada vez mais utilizadas nas diferentes ?reas de gest?o. O presente trabalho apresenta uma proposta para a sistematiza??o das atividades de DCBD a qual integra as metodologias CRISP-DM, SEMMA, FAYYAD, em um ambiente interativo, bem como um estudo de viabilidade do uso de an?lise de regress?o linear m?ltipla para explica??o de vendas, no setor corporativo de telecomunica??es, utilizando indicadores de desempenho. Foi delineado um m?todo estat?stico para analisar o efeito que os indicadores de desempenho t?m sobre o comportamento da produtividade de venda. Mediante an?lises estat?sticas e comerciais criteriosas, as equa??es foram definidas, sendo ajustados os seus respectivos coeficientes de determina??o. Foram tamb?m realizados testes de hip?teses de seus par?metros, visando ? valida??o ou n?o dos modelos de regress?o e an?lise da qualidade de seus ajustamentos. Ficou evidenciada a exist?ncia de relacionamento entre as caracter?sticas desses indicadores de desempenho com o volume de vendas realizado
630

Optimisation et simulation d'une chaîne logistique : application au secteur de l'agriculture / Supply chain optimization and simulation : an application to agricultural sector

Borodin, Valeria 01 December 2014 (has links)
Dans le cadre de la thèse portant sur l’optimisation et simulation de la chaîne logistique agricole, c'est l'activité de collecte qui est concernée, la période de moisson étant primordiale en matière de quantité et qualité de production, i.e. des revenus pour les agri-culteurs et des richesses pour le territoire. Plus spécifiquement, celle-ci implique les opérations de récolte, transport et stockage des céréales, réalisées par plusieurs exploitations agricoles, dispersées géographiquement. En vue d'aborder la complexité et la nature dyna-mique de la chaîne logistique d’une coopérative agricole française dans son intégralité, nous avons développé un système d'aide à la décision, qui s'inscrit dans la cadre de la recherche opérationnelle (RO) et plus précisément se réfère à l'optimisation linéaire, robuste et stochastique; la simulation de flux à évènements discrets; ainsi qu'à leur couplage. De plus, la synergie créée entre les outils de la RO, le système d’information géographique, la statistique inférentielle et prédictive rend le système d'aide à la décision compétitif et performant, capable de répondre convenablement au besoin de l’industriel / To overcome the new challenges facing agricultural sector, imposed by globalisation, changing market demands and price instability, the crop production supply chain must particularly be very reactive, flexible, with a high yield and at low cost. Its improving and eventual re-configuration can lead to an upgrade in efficiency, responsiveness, business integration and make it able to confront the market competitiveness. The thesis is thus placed in this particular context and aims to support decision making in crop harvesting activity, which is considered the pivotal stage in the cereal production circuit owing to its high cost and impact on the returns earned. Managing the harvest activity involves gathering, transportation and storage operations, performed by a collection of agricultural holdings geographically dispersed. Besides its practical relevance, this thesis forms part of the Operational Research (OR) and more specifically, refers to the linear and stochastic programming, discrete event simulation, and their coupling. In addition, the synergy created between OR, inferential and predictive statistics, geographical information system tools makes the decision support system competitive, efficient and responsive

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