Thesis (MComm (Logistics))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Mobile phone networks form an integral part of economic and social development globally. Mobile phones have become an everyday part of life and it is hard to imagine a competitive economy without the availability of mobile communications. Emerging markets benefit most from the implementation of mobile technology and growth trends are outperforming earlier predictions. The most popular and sustainable payment model used by mobile phone networks in emerging markets is the pre paid mechanism used for the distribution of airtime. This mechanism brings about unique challenges for networks in emerging markets. In this thesis the importance of the mobile phone network pre paid value channel is introduced through an analysis of pre paid revenue. A brief introduction is given to the systems and products that contribute to the functioning of the pre paid value channel. The revenue generation process is described with regards to the pre paid sector of the market and an in-depth explanation of the importance of deferred revenue is given, how it is recorded and what role it fulfils in the generation of revenue. The complexity of the network environment, both technical and operational makes the use of a business automation and support system (BSS) a necessary tool for effective execution of tasks and processes within the network environment. These systems record information from a wide spectrum of available technical network resources and use this information to automate the flow of network products. The use of such a system for the calculation of deferred revenue is suggested. Saaty‟s Analytical Hierarchy Process (AHP) algorithm and the Elimination and Choice Expressing Reality (ELECTRE) method are used to compare the newly proposed method for the calculation of deferred revenue using a BSS. Using Saaty's algorithm to estimate the effectiveness of deferred revenue as reported through the use of a BSS yields favourable results for the proposed method. This helps to bridge the gap in the poorly researched mobile telecommunications industry. ELECTRE is used to substantiate the findings of the model using AHP and meaningful tests are done to motivate correctness and accuracy of the results obtained throughout. Most importantly, the findings were shared with academic and industry experts, adding meaningful resemblance to the goals set out to achieve. / AFRIKAANSE OPSOMMING: Mobiele foon netwerke is wêreldwyd 'n onlosmaakbare deel van ekonomiese en sosiale ontwikkeling. Mobiele fone is deel van ons alledaagse lewe en dit is moeilik om 'n kompeterende ekonomie te bedink sonder die beskikbaarheid van mobiele kommunikasie. Ontluikende markte trek die meeste voordeel uit die implementering van mobiele tegnologie en groeitendense vertoon beter as wat vroeër voorspel is. Die mees gewilde en volhoubare betaalmetode wat deur mobiele foon netwerke in ontluikende markte gebruik word, is die voorafbetalingsmeganisme wat vir die verspreiding van lugtyd gebruik word. Hierdie meganisme bring unieke uitdagings vorendag in ontluikende markte. Die tesis beskryf die belangrikheid van die mobiele foon netwerk voorafbetalingswaardekanaal deur 'n analise te maak van vooruitbetalingsinkomste. 'n Kort oorsig oor die sisteme en produkte wat bydra tot die funksionering van die vooruitbetalingswaardekanaal word verskaf. 'n Beskrywing van die inkomste-genereringsproses vir die vooruitbetaling-sektor van die mark word verskaf en 'n in-diepte verduideliking van die belangrikheid van uitgestelde inkomste, hoe dit vasgelê word en watter rol dit speel in die generering van inkomste word verduidelik. Die kompleksiteit van die netwerkomgewing, beide op 'n tegniese en operasionele vlak, maak die gebruik van 'n besigheidsoutomatisering en ondersteuningsisteem (BSS) 'n noodsaaklike instrument vir die effektiewe uitvoer van take en prosesse binne die netwerkomgewing. Hierdie sisteme stoor informasie vanuit 'n wye spektrum van beskikbare tegniese netwerkbronne en gebruik die inligting om die vloei van netwerkprodukte te outomatiseer. Die gebruik van sodanige sisteem word voorgestel vir die berekening van uitgestelde inkomste. Saaty se Analitiese Hierargie Proses-algoritme (AHP) en die Eliminasie en Realiteit-Deur-Keuse Uitdrukkingsmetode (ELECTRE) word gebruik vir die vergelyking van die voorgestelde metode vir die berekening van uitgestelde inkomste deur middel van 'n BSS. Die gebruik van Saaty se algoritme om die effektiwiteit te bereken van uitgestelde inkomste soos gemeld deur die gebruik van 'n BSS, lewer gunstige resultate vir die voorgestelde metode. Dit vul 'n leemte in die swak nagevorsde mobiele telekommunikasie industrie. ELECTRE word gebruik om die bevindinge van die AHP-model te substansieer en betekenisvolle toetse word deurentyd gedoen om die korrektheid en akkuraatheid van die resultate te motiveer. Die belangrikste aspek van die navorsing is dat die bevindinge gedeel is met kenners binne die akademie sowel as die industrie, wat nou aansluit by die doelstellings wat aanvanklik beoog is.

Change from a regulated to deregulated structure means that, the centralized maintenance system is not valid any more. In the surveyed published literature, there is not a single model which incorporates all maintenance cost components to analyze the effect of different maintenance strategies for generator companies (GENCOs). The work enclosed in this thesis demonstrates that there is a considerable requirement for accurately modelling cost components of the maintenance model, to be used in maintenance scheduling for deregulated power system, in order to attain a superior schedule with major financial and operational impact. This research investigates and models most cost factors that affect the maintenance activities of the deregulated GENCOs, and demonstrates the utilization of the developed cost models in maintenance scheduling. It also presents the data gathering process for the developed maintenance cost model. A generator maintenance scheduling model that considers direct and indirect maintenance costs, opportunity costs (i.e. loss of customer goodwill), effective maintenance strategies, failures, and interruptions is developed. A Genetic Algorithm (GA) based approach is employed to achieve maintenance schedules to various generators maintenance scenarios. An Analytical Hierarchy Process (AHP) approach is proposed for modelling customer goodwill. The maintenance model was redeveloped under the Reliability Centred Maintenance (RCM) strategy to analyze the effect of a maintenance strategy on maintenance costs. Case studies are presented to demonstrate the utilisation of the developed models.The investigation shows that the market prices, opportunity costs and maintenance strategy have an effect on the final maintenance schedule. The research demonstrates that the cost components are critical factors to achieve an effective maintenance schedule, and they must be considered and carefully modelled in order to reflect more realistic situation for maintenance scheduling of generator units in deregulation environment.

Este trabalho descreve um experimento sobre o processo de decisão para priorização de projetos de melhoria em uma indústria de bens de capital. Apenas dois critérios eram aplicados na tarefa de priorizar projetos; exigências legais e complexidade técnica, então, foi proposto avaliar os projetos através de um conjunto mais amplo de critérios, incluindo imagem da marca, participação de mercado, alinhamento estratégico, tempo de lançamento de um novo produto. Para lidar com um número maior de critérios qualitativos e quantitativos, foi introduzido desde então, dois métodos multicritérios, a saber: o uso do AHP (analytical hierarchic process) e o DS-AHP (Dempster-Shafer /AHP). Os fundamentos teóricos dos dois métodos são apresentados. O primeiro método é usado para determinar as importâncias relativas das alternativas, por meio de ponderações em cada nível da estrutura hierárquica; a qualidade dos julgamentos é avaliada por um \"índice de consistência\". O segundo método também utiliza a plataforma de análise do AHP acrescentado mensuração da ignorância no processo de julgamentos por meio de probabilidades subjetivas. São comentadas as aplicações dos métodos em uma específica indústria. Foram observadas objeções dos decisores à aplicação do processo AHP, decorrentes da necessidade de numerosas re-avaliações dos julgamentos, quando o \"índice de consistência\" apresentava-se maior que os valores recomendados. Como ponto positivo foi destacada a simplicidade do método para aplicações no ambiente empresarial. Quanto ao método DS-AHP, o uso do conceito de crença nos julgamentos dos decisores, permitiu melhores aproximações às situações reais; neste caso, a alternativa eleita pôde ser claramente compreendida como a mais provável, e não classificada como provavelmente ou certamente a melhor. O DS-AHP quandocomparado ao AHP apresenta-se como um ferramental de condução mais direta para a obtenção dos resultados principalmente no que se refere ao menor número de comparações exigidas, também ajuda o decisor a identificar e corrigir as possíveis fontes de ignorância, que podem afetar a qualidade da decisão. / This study describes an experiment about the definition of portfolio of improvement projects in an industry of capital goods, which had until recently been prioritized based mainly on legislation demand and technical complexity. It was proposed to increase the criteria numbers including: market image, market share, strategic alignment, launch time to new products. To handle several criteria with focus quantitative and qualitative aspects was necessary introduced two multcriterial methods, namely, analytical hierarchic process (AHP) and Dempster-Shafer AHP process (DS-AHP). The first referred method is used to manage the relative importance of alternatives regarding the fore mentioned criteria based on weights attributed to structure hierarchical levels. The second referred method also uses AHP platform to enable ignorance measurement based on subjective probabilities. Results from direct application of the methods in this specific industry are commented. It was observed that the decision makers have some objections with respect to the AHP process, in the sense that there were judgment inconsistencies which required additional evaluation of the candidate solutions, what was seen as somewhat tiresome. The main advantages which was emphasize by decision makers refers to the ease of application in corporate environmental . As for the DS - AHP process, the possibility of considering believes in a structured way was felt as more appropriated to the real decision process, which effectively involves uncertainties. In this way, the elected alternative can be clearly understood as most probably - and not certainly - the best. Also the DS-AHP process was seen as more directly conducive to the final results in comparison with the AHP process.

Submitted by ADRIANO MARTINS JUNQUEIRA null (adriano@geopx.com.br) on 2017-03-11T20:17:10Z No. of bitstreams: 1 Mestrado - Adriano Martins Junqueira - 2017.pdf: 8109678 bytes, checksum: d1e6cf6e83e8eac0c87d3eb5b494f810 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2017-03-16T20:19:44Z (GMT) No. of bitstreams: 1 junqueira_am_me_guara.pdf: 8109678 bytes, checksum: d1e6cf6e83e8eac0c87d3eb5b494f810 (MD5) / Made available in DSpace on 2017-03-16T20:19:44Z (GMT). No. of bitstreams: 1 junqueira_am_me_guara.pdf: 8109678 bytes, checksum: d1e6cf6e83e8eac0c87d3eb5b494f810 (MD5) Previous issue date: 2017-01-18 / A maioria dos empreendimentos do setor elétrico brasileiro não apresentam uma avaliação sistemática espaço-temporal de suas estruturas para identificar vulnerabilidades ambientais nos empreendimentos. Assim, este estudo teve como objetivo analisar a susceptibilidade de movimento de massa em linhas de transmissão, na região da Serra da Mantiqueira, sujeitas aos efeitos de chuvas tropicais e operacionalizar uma plataforma dinâmica de análise e alerta nas áreas de maior criticidade. Para este trabalho, foram levantados dados estáticos e dinâmicos na região a partir de fontes de acesso público e privado. A seguir, foram definidos os múltiplos critérios através do processo de análise hierárquica (AHP). Utilizando Sistemas de Informações Geográficas (SIG) e álgebra de mapas, foi possível determinar o mapa de susceptibilidade em cinco classes e operacionalizar a plataforma de monitoramento, análise e alerta a riscos ambientais baseando-se nas áreas identificadas e nos dados dinâmicos meteorológicos e hidrológicos. Como resultado, foi gerado um banco de dados geográfico com abrangência regional (14.000 km²), que envolveu 7 critérios: declividade, distância das linhas de transmissão, densidade de drenagem, uso do solo, tipo do solo, densidade de fraturas e falhas, e precipitação. A distribuição das classes de susceptibilidade encontradas na região de estudo foram: muito baixa (1,5%), baixa (12%), média (34,9%), alta (45,3%) e muito alta (6,2%). Foi possível ainda, identificar diferentes movimentos de massa em áreas próximas à linhas de transmissão, quanto próximas aos outros elementos de risco, como moradias, estradas, bordas de reservatórios e torres de telecomunicações. A plataforma de monitoramento operacionalizada possibilitou o estabelecimento de análises dinâmicas sobre a ocorrência de eventos naturais extremos, através do envio de notificações e acesso WEB com o mapa das áreas afetadas. Assim, este estudo pode se tornar um instrumento de avaliação, acompanhamento e gerenciamento para a gestão pública e agências reguladoras do setor elétrico. / Most of the Brazilian electric sector enterprises do not present a systematic space-time evaluation of their structures to identify environmental vulnerabilities in the projects. Thus, this study aimed to analyze the susceptibility of mass movement in transmission lines, in the Serra da Mantiqueira region, subject to the effects of tropical rains and to operationalize a dynamic platform of analysis and alertness in the most critical areas. For this work, static and dynamic data were collected in the region from public and private sources. Next, the multiple criteria were defined through the hierarchical analysis process (AHP). Using Geographic Information Systems (GIS) and map algebra, it was possible to determine the susceptibility map in five classes and to operationalize the monitoring platform for monitoring, analysis and alert to environmental risks based on identified areas and dynamic meteorological and hydrological data. As a result, a geographic database with a regional coverage (14.000 km²) was generated, involving 7 criteria: slope, distance of transmission lines, drainage density, soil use, soil type, fracture and failure density, and precipitation. The distribution of susceptibility classes found in the study region were very low (1.5%), low (12%), average (34.9%), high (45.3%) and very high (6, 2%). It was also possible to identify different mass movements in areas close to the transmission lines, as well as to other risk elements such as dwellings, roads, reservoir borders and telecommunications towers. The operationalized monitoring platform allowed the establishment of dynamic analyzes on the occurrence of extreme natural events, by sending notifications and WEB access with the map of the affected areas. Thus, this study can become an instrument of evaluation, monitoring and management for the public management and regulatory agencies of the electric sector.

Our country is a risky position in terms of natural disasters. In the long run, preferentially settlement areas were selected to ensure maximum benefits in terms of both economic and security aspects, other criteria is not taken account when selection of sites. The main purpose of this study is to examine and compare the properties of settlement location based on natural hazard and environmental constraints to be able to understand the interaction between the settlements and natural conditions at the regional scale of YeSilirmak Basin. A MCDA was set up with 10 different data layers in two data domains (environmental and natural hazards domains), are evaluated. The results of the MCDA scores are then transferred to settlement databases in order to evaluate the number of existing settlements in different environmental and natural hazard related suitability classes. It is found that almost 29% of YeSilirmak catchment is environmentally favorable for settlement, and in coherence with that 41% of all existing settlements are located in this zone, indicating a clear preference among the perception of environmentally better places to be settled in. On the other hand with respect to the natural hazards dataset, the locations of the settlements fail to create any preference, as 73,32% of the area is used by 73,50% of existing settlements, which indicates that the perception of natural hazards are low and do not effect settlement criteria, while the acceptable risk of community is high.

Submitted by MELINA FUSHIMI (melinafushimi@yahoo.com.br) on 2016-06-27T15:24:06Z No. of bitstreams: 1 TESE_FINAL_Melina Fushimi.pdf: 21884758 bytes, checksum: 0c1b17ce557210c1ae752004961a846d (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-28T17:14:34Z (GMT) No. of bitstreams: 1 fushimi_m_dr_prud.pdf: 21884758 bytes, checksum: 0c1b17ce557210c1ae752004961a846d (MD5) / Made available in DSpace on 2016-06-28T17:14:34Z (GMT). No. of bitstreams: 1 fushimi_m_dr_prud.pdf: 21884758 bytes, checksum: 0c1b17ce557210c1ae752004961a846d (MD5) Previous issue date: 2016-06-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No atual momento histórico, diante das transformações aceleradas das paisagens, em que as dinâmicas da sociedade se interpenetram e, muitas vezes, se sobressaem às dinâmicas da natureza, a questão ambiental assume importância em vários campos do conhecimento, sobretudo, na Geografia. Em meio aos diversos trabalhos desenvolvidos no âmbito geográfico e ambiental, tem-se a erosão como um dos assuntos mais enfatizados. Neste contexto, o objetivo geral da tese foi analisar os principais elementos que influenciam na vulnerabilidade ambiental aos processos erosivos lineares (sulcos, ravinas e voçorocas) de parte dos municípios de Marabá Paulista-SP e Presidente Epitácio-SP. Sob a perspectiva teórico-metodológica do pensamento da complexidade, foram caracterizados os aspectos do relevo, declividade, solos, substrato rochoso, cobertura vegetal, curvatura da superfície e uso da terra, além da elaboração de documentos cartográficos em ambiente de Sistemas de Informação Geográfica, em especial, o mapa de vulnerabilidade ambiental aos processos erosivos lineares. Em virtude das possibilidades de integração dos dados e atribuição de pesos, o referido mapa foi realizado a partir da lógica fuzzy, especificamente, da Técnica do Processo Analítico Hierárquico (AHP), a qual proporcionou o mapeamento de maneira classificada: baixa (0.32%), média (65.15%), alta (34.45%) e muito alta vulnerabilidade (0.08%). A baixa vulnerabilidade está elencada às matas ciliares remanescentes. A média vulnerabilidade se localiza nos topos das colinas com declividades inferiores a 5%. O uso da terra predominante é a pastagem e os solos são, em sua maioria, desenvolvidos e arenosos. A alta vulnerabilidade está, principalmente, nas vertentes convexas e retilíneas, em que as inclinações podem alcançar 15%. A pastagem prevalece, todavia, verificou-se a expansão do cultivo de cana de açúcar e do solo exposto para seu consecutivo plantio. A muito alta vulnerabilidade apresenta-se nas vertentes côncavas, cuja curvatura favorece a convergência das águas pluviais e, portanto, o fluxo linear. Tal evento se intensifica perante às declividades acentuadas – superiores a 20% para a região. Combinado a estes atributos, sobre solos rasos tem-se o pastoreio intensivo do gado, o qual acelera a compactação do solo e acarreta a erosão, sendo uma das formas de degradação mais recorrente no Extremo Oeste Paulista. Assim, o presente estudo pode contribuir no sentido de orientar a implantação de medidas preventivas e corretivas de controle à erosão por intermédio do planejamento ambiental. / In the current historical moment, given the accelerated changes in landscapes, in which the dynamics of society interpenetrate and, often, exceed the dynamics of nature, the environmental issue assumes importance in several fields of knowledge, especially, Geography. Among the diverse assignments developed in geographical and environmental contexts, erosion is one of the most commonly emphasized subjects. Therefore, this thesis aimed to analyze the main elements that influence environmental vulnerability to linear erosive processes (rills, ravines and gullies) in parts of Marabá Paulista-SP and Presidente Epitácio-SP. From the theoretical-methodological perspective of thought complexity, the relief, slope plans, soils, bedrocks, vegetation, surface curvature and land use aspects were characterized, in addition to the elaboration of cartographic documents using the Geographic Information System, in particular, the map of environmental vulnerability to linear erosive processes. Due to the possibilities of integrating data and assigning weights, the map was performed based on fuzzy sets, specifically, the Analytical Hierarchy Process (AHP), which provided classified mapping: low (0.32%), medium (65.15%), high (34.45%) and very high vulnerability (0.08%). The low vulnerability is identified in the reminiscent cilliary forests. The medium vulnerability is located on the hilltops with slopes of less than 5%. The land use is predominantly for pasture and soils are for the most part developed and sandy. The high vulnerability is primarily the convex and rectilinear aspects, where the slopes can reach 15%. On the prevailing pasture, however, the expansion of the sugar cane crop was found and soil exposed to its successive planting. The very high vulnerability is present in the concave slopes, whose curvature favors the convergence of rainwater and thus, linear flow. This event is intensified towards the steep slopes – more than 20% of the region. Combined with these attributes, on shallow soils there is intensive grazing of livestock, which accelerates soil compaction and leads to erosion, one of the most recurrent means of degradation in the Far West of São Paulo. Thus, the present study may contribute to guiding the management of preventive and corrective measures to control erosion through environmental planning.

Este trabalho descreve um experimento sobre o processo de decisão para priorização de projetos de melhoria em uma indústria de bens de capital. Apenas dois critérios eram aplicados na tarefa de priorizar projetos; exigências legais e complexidade técnica, então, foi proposto avaliar os projetos através de um conjunto mais amplo de critérios, incluindo imagem da marca, participação de mercado, alinhamento estratégico, tempo de lançamento de um novo produto. Para lidar com um número maior de critérios qualitativos e quantitativos, foi introduzido desde então, dois métodos multicritérios, a saber: o uso do AHP (analytical hierarchic process) e o DS-AHP (Dempster-Shafer /AHP). Os fundamentos teóricos dos dois métodos são apresentados. O primeiro método é usado para determinar as importâncias relativas das alternativas, por meio de ponderações em cada nível da estrutura hierárquica; a qualidade dos julgamentos é avaliada por um \"índice de consistência\". O segundo método também utiliza a plataforma de análise do AHP acrescentado mensuração da ignorância no processo de julgamentos por meio de probabilidades subjetivas. São comentadas as aplicações dos métodos em uma específica indústria. Foram observadas objeções dos decisores à aplicação do processo AHP, decorrentes da necessidade de numerosas re-avaliações dos julgamentos, quando o \"índice de consistência\" apresentava-se maior que os valores recomendados. Como ponto positivo foi destacada a simplicidade do método para aplicações no ambiente empresarial. Quanto ao método DS-AHP, o uso do conceito de crença nos julgamentos dos decisores, permitiu melhores aproximações às situações reais; neste caso, a alternativa eleita pôde ser claramente compreendida como a mais provável, e não classificada como provavelmente ou certamente a melhor. O DS-AHP quandocomparado ao AHP apresenta-se como um ferramental de condução mais direta para a obtenção dos resultados principalmente no que se refere ao menor número de comparações exigidas, também ajuda o decisor a identificar e corrigir as possíveis fontes de ignorância, que podem afetar a qualidade da decisão. / This study describes an experiment about the definition of portfolio of improvement projects in an industry of capital goods, which had until recently been prioritized based mainly on legislation demand and technical complexity. It was proposed to increase the criteria numbers including: market image, market share, strategic alignment, launch time to new products. To handle several criteria with focus quantitative and qualitative aspects was necessary introduced two multcriterial methods, namely, analytical hierarchic process (AHP) and Dempster-Shafer AHP process (DS-AHP). The first referred method is used to manage the relative importance of alternatives regarding the fore mentioned criteria based on weights attributed to structure hierarchical levels. The second referred method also uses AHP platform to enable ignorance measurement based on subjective probabilities. Results from direct application of the methods in this specific industry are commented. It was observed that the decision makers have some objections with respect to the AHP process, in the sense that there were judgment inconsistencies which required additional evaluation of the candidate solutions, what was seen as somewhat tiresome. The main advantages which was emphasize by decision makers refers to the ease of application in corporate environmental . As for the DS - AHP process, the possibility of considering believes in a structured way was felt as more appropriated to the real decision process, which effectively involves uncertainties. In this way, the elected alternative can be clearly understood as most probably - and not certainly - the best. Also the DS-AHP process was seen as more directly conducive to the final results in comparison with the AHP process.

Forward osmosis (FO) is an emerging technology for water treatment due to their ability to draw freshwater using an osmotic pressure gradient across a semi-permeable membrane. However, the lack of draw agents that could both produce reasonable flux and be separated from the draw solution at a low cost stand in the way of widespread implementation. This study had two objectives: evaluate the performance of three materials — peptone, carboxymethyl cellulose (CMC), and magnetite nanoparticles (Fe3O4 NPs) — as potential draw agents, and to use multi-criteria decision matrices to systematically prioritize known draw agents from literature for research investigation. Peptone showed water flux and reverse solute flux values comparable to other organic draw agents. CMC’s high viscosity made it impractical to use and is not recommended as a draw agent. Fe3O4 NPs showed average low fluxes (e.g., 2.14 LMH) but discrete occurrences of high flux values (e.g., 14 LMH) were observed during FO tests. This result indicates that these nanoparticles have potential as draw agents but further work is needed to optimize the characteristics of the nanoparticle suspension. Separation of the nanoparticles from the product water using coagulation was shown to be theoretically possible if only electrostatic and van der Waals forces are taken into account, not steric repulsion. If coagulation is to be considered for separation, research efforts on development of nanoparticle suspensions as FO draw agents should focus on development of electrostatically stabilized nanoparticles. A combination of Fe3O4 NP and peptone showed a higher flux than Fe3O4 NPs alone, but did not produce additive or synergistic flux. This warrants further research to investigate more combinations of draw agents to achieve higher flux than that obtained by individual draw agents. Potential draw agents were prioritized by conducting a literature review of draw agents, extracting data on evaluation criteria for draw agents developed over the past five years, using these data to rank the draw agents using the Analytical Hierarchy Process (AHP) and Technique for Order of Preference by Similarity to Ideal Solutions (TOPSIS). The evaluation criteria used in the ranking matrices were water flux, reverse solute flux, replenishment cost, regeneration cost, and regeneration efficacy. The results showed that the top five ranked draw agents were P-2SO3-2Na, TPHMP-Na, PEI-600P-Na, NaCl, and NH4-CO2. The impact of the assumption made during the multi-criteria decision analysis process was evaluated through sensitivity analyses altering criterion weighting and including more criteria. This ranking system provided recommendations for future research and development on draw agents by highlighting research gaps.

Change from a regulated to deregulated structure means that, the centralized maintenance system is not valid any more. In the surveyed published literature, there is not a single model which incorporates all maintenance cost components to analyze the effect of different maintenance strategies for generator companies (GENCOs). The work enclosed in this thesis demonstrates that there is a considerable requirement for accurately modelling cost components of the maintenance model, to be used in maintenance scheduling for deregulated power system, in order to attain a superior schedule with major financial and operational impact. This research investigates and models most cost factors that affect the maintenance activities of the deregulated GENCOs, and demonstrates the utilization of the developed cost models in maintenance scheduling. It also presents the data gathering process for the developed maintenance cost model. A generator maintenance scheduling model that considers direct and indirect maintenance costs, opportunity costs (i.e. loss of customer goodwill), effective maintenance strategies, failures, and interruptions is developed. A Genetic Algorithm (GA) based approach is employed to achieve maintenance schedules to various generators maintenance scenarios. An Analytical Hierarchy Process (AHP) approach is proposed for modelling customer goodwill. The maintenance model was redeveloped under the Reliability Centred Maintenance (RCM) strategy to analyze the effect of a maintenance strategy on maintenance costs. Case studies are presented to demonstrate the utilisation of the developed models.The investigation shows that the market prices, opportunity costs and maintenance strategy have an effect on the final maintenance schedule. The research demonstrates that the cost components are critical factors to achieve an effective maintenance schedule, and they must be considered and carefully modelled in order to reflect more realistic situation for maintenance scheduling of generator units in deregulation environment.

Klimatförändringarna och den globala uppvärmningen är ett faktum som kan leda till kraftigare nederbördstillfällen samt öka risken för bland annat översvämningar. Översvämningsrelaterade katastrofer har under de senaste 20 åren ökat och översvämningsrelaterade händelser står för 44 procent av världens naturkatastrofer. Samtidigt ökar tillväxten av många städer och samhällen vilket sätter större krav på beslutsfattare och kommuner att välja lämpliga platser för exploatering. Syftet med studien är att undersöka hur en GIS-baserad multikriterieanalys kan användas för att identifiera översvämningsrisker samt hur karteringen över översvämningsrisker vidare kan användas för att identifiera lämpliga platser för bostadsexploatering. Studien utfördes genom att intervjua översvämningsexperter och samhällsplanerare, samt genom att använda geografiska informationssystems (GIS)-baserade metoder såsom Multikriterieanalys (MKA), Analytisk hieratisk process (AHP) och känslighetsanalys. Intervjuerna gav värdefulla synpunkter på kriterier, rangordning och viktning. Resultaten av översvmningsriskkarteringen visar de områden som har mycket hög till mycket låg risk att exponeras för en översvämning. För att identifiera lämpliga platser för bostadsutveckling användes översvämningsriskkarteringen som ett kriterium tillsammans med andra viktiga komponenter såsom fysiska och sociala faktorer. Resultaten visar att den lämpligaste platsen är lokaliserad i den sydvästra delen av Näringen och har en storlek på 25 737 kvadratmeter (kvm). Den känslighetsanalys som utfördes i studien, genom att ändra rangordningen på kategorierna (översvämningsrisk, fysiska- och sociala faktorer), visade det att den största förändringen skedde när de sociala faktorerna fick en hög rangordning och vikt. Diskussionen och slutsatsen visar hur bland annat valet av kriterier och intervjupersoner kan påverka resultatet och att det finns många osäkerheter med att använda MKA. Resultatet av en MKA bör därför utvärderas om det ska vara möjligt att avgöra om bostäder kan exploateras på Näringen. / Climate change and global warming are some causes that can lead to heavier precipitation and increased risk of floods. Flood-related disasters have increased over the past 20 years and 44 percent of the world's natural disasters are due to flood-related events. At the same time, the growth is increasing in many of the world's cities and communities, which places greater demands on decision-makers and municipalities to choose suitable places for exploitation. The purpose of the study is to investigate how a GIS-based multi-criteria analysis can be used to identify flood risks and how the mapping of flood risks can be used further to identify suitable sites for housing development. The study was conducted by interviewing flood experts and urban planners and implementing Geographic Information Systems (GIS)-based method such as Multi-criteria Analysis (MCA), Analytical Hierarchy Process (AHP) and Sensitivity Analysis to produce the results. The respondents provided valuable views on the criteria, ranking and weighting of criteria. The results of the flood hazard map show the areas that are at high and low risk of being flooded. In finding suitable sites for housing development, the flood hazard map was used as an input together with other important components such physical and social factors. The results show that the most suitable place is in the southwestern part of Näringen, which has a size of 25 737 m2. In the sensitivity analysis that was performed where ranking of the categories was changed (flood risk, physical and social factors), it showed that the biggest change took place when the social factors received high ranking and weight. The discussion and conclusion show how the choice of criteria, weighting and interviews can affect the results and the many uncertainties with using MCA. The results of an MCA should therefore be evaluated if it is to be possible to decide whether housing can be exploited on Näringen.