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A Time-Evolving Optimization Model for an Intermodal Distribution Supply Chain Network:!A Case Study at a Healthcare CompanyJohansson, Sara, Westberg, My January 2016 (has links)
Enticed by the promise of larger sales and better access to customers, consumer goods compa- nies (CGCs) are increasingly looking to evade traditional retailers and reach their customers directly–with direct-to-customer (DTC) policy. DTC trend has emerged to have major im- pact on logistics operations and distribution channels. It oers significant opportunities for CGCs and wholesale brands to better control their supply chain network by circumventing the middlemen or retailers. However, to do so, CGCs may need to develop their omni-channel strategies and fortify their supply chains parameters, such as fulfillment, inventory flow, and goods distribution. This may give rise to changes in the supply chain network at all strategic, tactical and operational levels. Motivated by recent interests in DTC trend, this master thesis considers the time-evolving supply chain system of an international healthcare company with preordained configuration. The input is bottleneck part of the company’s distribution network and involves 20% ≠ 25% of its total market. A mixed-integer linear programming (MILP) multiperiod optimization model is developed aiming to make tactical decisions for designing the distribution network, or more specifically, for determining the best strategy for distributing the products from manufacturing plant to primary distribution center and/or regional distribution centers and from them to customers. The company has got one manufacturing site (Mfg), one primary distribution center (PDP) and three dierent regional distribution centers (RDPs) worldwide, and the customers can be supplied from dierent plants with various transportation modes on dierent costs and lead times. The company’s motivation is to investigate the possibility of reduction in distribution costs by in-time supplying most of their demand directly from the plants. The model selects the best option for each customer by making trade-os among criteria involving distribution costs and lead times. Due to the seasonal variability and to account the market fluctuability, the model considers the full time horizon of one year. The model is analyzed and developed step by step, and its functionality is demonstrated by conducting experiments on the distribution network from our case study. In addition, the case study distribution network topology is utilized to create random instances with random parameters and the model is also evaluated on these instances. The computational experiments on instances show that the model finds good quality solutions, and demonstrate that significant cost reduction and modality improvement can be achieved in the distribution network. Using one-year actual data, it has been shown that the ratio of direct shipments could substantially improve. However, there may be many factors that can impact the results, such as short-term decisions at operational level (like scheduling) as well as demand fluctuability, taxes, business rules etc. Based on the results and managerial considerations, some possible extensions and final recommendations for distribution chain are oered. Furthermore, an extensive sensitivity analysis is conducted to show the eect of the model’s parameters on its performance. The sensitivity analysis employs a set of data from our case study and randomly generated data to highlight certain features of the model and provide some insights regarding its behaviour.
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Analyse de sensibilité de modèles spatialisés : application à l'analyse coût-bénéfice de projets de prévention du risque d'inondation / Variance-based sensitivity analysis for spatially distributed models : application to cost-benefit analysis of flood risk management plansSpatially distributed model; Sensitivity analysis; Uncertainty; Scale; Geostatistics;CBA; Flood; Damage.Saint-Geours, Nathalie 29 November 2012 (has links)
L'analyse de sensibilité globale basée sur la variance permet de hiérarchiser les sources d'incertitude présentes dans un modèle numérique et d'identifier celles qui contribuent le plus à la variabilité de la sortie du modèle. Ce type d'analyse peine à se développer dans les sciences de la Terre et de l'Environnement, en partie à cause de la dimension spatiale de nombreux modèles numériques, dont les variables d'entrée et/ou de sortie peuvent être des données distribuées dans l'espace. Le travail de thèse réalisé a pour ambition de montrer comment l'analyse de sensibilité globale peut être adaptée pour tenir compte des spécificités de ces modèles numériques spatialisés, notamment la dépendance spatiale dans les données d'entrée et les questions liées au changement d'échelle spatiale. Ce travail s'appuie sur une étude de cas approfondie du code NOE, qui est un modèle numérique spatialisé d'analyse coût-bénéfice de projets de prévention du risque d'inondation. On s'intéresse dans un premier temps à l'estimation d'indices de sensibilité associés à des variables d'entrée spatialisées. L'approche retenue du « map labelling » permet de rendre compte de l'auto-corrélation spatiale de ces variables et d'étudier son impact sur la sortie du modèle. On explore ensuite le lien entre la notion d'« échelle » et l'analyse de sensibilité de modèles spatialisés. On propose de définir les indices de sensibilité « zonaux » et « ponctuels » pour mettre en évidence l'impact du support spatial de la sortie d'un modèle sur la hiérarchisation des sources d'incertitude. On établit ensuite, sous certaines conditions, des propriétés formelles de ces indices de sensibilité. Ces résultats montrent notamment que l'indice de sensibilité zonal d'une variable d'entrée spatialisée diminue à mesure que s'agrandit le support spatial sur lequel est agrégée la sortie du modèle. L'application au modèle NOE des méthodologies développées se révèle riche en enseignements pour une meilleure prise en compte des incertitudes dans les modèles d'analyse coût-bénéfice des projets de prévention du risque d'inondation. / Variance-based global sensitivity analysis is used to study how the variability of the output of a numerical model can be apportioned to different sources of uncertainty in its inputs. It is an essential component of model building as it helps to identify model inputs that account for most of the model output variance. However, this approach is seldom applied in Earth and Environmental Sciences, partly because most of the numerical models developed in this field include spatially distributed inputs or outputs . Our research work aims to show how global sensitivity analysis can be adapted to such spatial models, and more precisely how to cope with the following two issues: i) the presence of spatial auto-correlation in the model inputs, and ii) the scaling issues. We base our research on the detailed study of the numerical code NOE, which is a spatial model for cost-benefit analysis of flood risk management plans. We first investigate how variance-based sensitivity indices can be computed for spatially distributed model inputs. We focus on the “map labelling” approach, which allows to handle any complex spatial structure of uncertainty in the modelinputs and to assess its effect on the model output. Next, we offer to explore how scaling issues interact with the sensitivity analysis of a spatial model. We define “block sensitivity indices” and “site sensitivity indices” to account for the role of the spatial support of model output. We establish the properties of these sensitivity indices under some specific conditions. In particular, we show that the relative contribution of an uncertain spatially distributed model input to the variance of the model output increases with its correlation length and decreases with the size of the spatial support considered for model output aggregation. By applying our results to the NOE modelling chain, we also draw a number of lessons to better deal with uncertainties in flood damage modelling and cost-benefit analysis of flood riskmanagement plans.
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Podnikatelský plán nízkonákladového golfového hřiště / Business plan of a low-cost golf courseBartulec, Jan January 2010 (has links)
The thesis is divided in two different parts. In the theoretical one we can find information about golf, its history, evolution and an opinion about it. This part also deals with the operating principles of a golf resort, an ownership structure and an existence of a golf club. At the end of theoretical part is described the structure of a business plan in detail. The business plan is based on a real project of a low-cost golf course. It respects the investor's requirements and is meant to be used as a manual for operating of this golf course. We can also find the procedure for establishing a golf club, the applied methods of segment analysis and the prediction of activities connected to the club in the future that respect the factor of risk.
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Modeling Science Achievement Differences Between Single-sex and Coeducational Schools: Analyses from Hong Kong, SAR and New Zealand from TIMSS 1995, 1999, AND 2003Diaconu, Dana V. January 2012 (has links)
Thesis advisor: Henry Braun / There is a broad interest in narrowing achievement gaps among all groups of students and improving education by scientifically sound methods. On October 25, 2006, the United States Department of Education published new regulations allowing single-sex education in public schools whenever schools think it will improve student achievement. Thus far, studies comparing single-sex with coeducational schools have been carried out at the national level mostly in England, Australia and Jamaica, while US' studies were limited to Catholic schools. Few studies reported descriptive statistics or effect sizes and most studies differ in the criteria and statistical controls they use to compare single-sex and coeducation. This dissertation presents models for science achievement and attitudes towards science for 8th -grade students attending either single-sex or coeducation schools in Hong Kong and New Zealand, using the Trends in Mathematics and Science Study (TIMSS) datasets from 1995, 1999, and 2003. To properly account for the nested structure of data, an HLM model was estimated for each sex, for each of the two jurisdictions at three time points, corresponding to the three TIMSS administrations. The within - country results were compared to see if differences between single-sex and coed schools were consistent over time. In addition, this dissertation proposed an approach to examine the sensitivity of the estimated effects of school-type on student outcomes to the presence of unmeasured variables which may introduce hidden selection bias, using a modification of the method proposed by Rosenbaum and Rubin (1983). Based on its conditional distribution with an instrumental variable, chosen based on the review of single-sex literature, the Monte Carlo simulated values of the unobserved variable were used as level-1 predictors in a one-way ANCOVA with random effects. The sensitivity analysis was limited to science achievement of Hong-Kong's girls in TIMSS 2003. Findings show that single-sex education contributed to girls' science performance and attitudes in NZL 1999 and HKG 1999 and 2003, and low sensitivity for school-type contrast. / Thesis (PhD) — Boston College, 2012. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Research, Measurement, and Evaluation.
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Improvement of mining efficiencies at Thamazimbi iron ore mineRodger, Sean James 14 November 2006 (has links)
Student Number : 9506626A -
MSc (Eng) research report -
School of Mining -
Faculty of Engineering and the Built Environment / Significant research has been carried out over the years into what effect blast designs and techniques have on the final product in the mining process. There are numerous parameters that can be altered to deliver downstream benefits – the key is to determine which changes are appropriate for the rock body in question.
A project is currently underway at Thabazimbi Iron Ore Mine (Northern Province, South Africa) to improve the operational efficiency through attention to the blasting operation. Previous research suggests changing fragmentation will have an effect on mining efficiency, but no definitive model has been developed directly linking the two. Using data collected during the project, the author developed a sensitivity analysis tool, which defines the effect of changing fragmentation on overall mine efficiency. This prediction model was based partly on theory and partly on empirical information gathered from mine databases and personnel. Over the course of this project, this model was validated through the practical implementation of the theory behind its development. This involved decreasing powder factors through increasing the drilling pattern, thus changing the resulting fragmentation of the muckpile. Subsequently, downstream effects on mining efficiency were monitored and these results were recorded in the model.
The proven model was then used to identify areas of opportunity for improvement. In this report two areas are discussed, firstly, the implementation of a doped emulsion replacing ANFO across the mine, and secondly the introduction of electronic detonators. The second option would require further test work to develop confidence in the assumptions made in the model, concerning the effect of timing accuracy on fragmentation.
This research report covers the background to the project, an explanation of the model and the final results obtained.
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[en] RFID APPLIED TO OPTICAL SPECTRUM FOR METROPOLITAN RING NETWORK RESOURCES INVENTORY AND ITS ECONOMIC IMPACT / [pt] UTILIZAÇÃO DA TECNOLOGIA RFID APLICADA NO ESPECTRO ÓPTICO PARA AVALIAÇÃO DOS RECURSOS DISPONÍVEIS EM ANÉIS METROPOLITANOS E SEU IMPACTO ECONÔMICOCLAUDIA BARUCKE MARCONDES PAES LEME 15 June 2009 (has links)
[pt] Ao longo do presente trabalho é apresentado o desenvolvimento de um
sistema operando na camada óptica física, que avalia o inventário de capacidade
de um anel óptico metropolitano. O sistema de RFID tradicional, utilizado
comercialmente para avaliação de estoques de uma cadeia de suprimentos, foi
adaptado para descrever a capacidade disponível dos elementos de rede dos nós
deste anel metropolitano. Para esta adaptação foi criado um código utilizando
subportadoras de RF, denominado EPC Telecom, compatível com os
procedimentos usuais aplicados na leitura e avaliação de etiquetas RFID
tradicionais. A partir do sistema RFID assim desenvolvido, o conceito de cadeia
de valores segundo Michael Porter é utilizado para avaliar o desempenho
econômico de operadoras de telecomunicações e os possíveis impactos quando da
utilização do sistema proposto. / [en] In this work, by using RFID, a technology globally employed in logistic and
supply chain control, a system operating at optical physical layer implements a
real time, reliable and distributed capacity inventory evaluation of metropolitan
ring networks. This system is achieved by introducing a binary combination of RF
subcarriers in the optical spectrum. The array of subcarriers is generated through a
new proposed code, denominated EPC Telecom, compatible with traditional
RFID codes. Also, the concept of value chain according Michael Porter is
employed to evaluate the economic performance of telecommunications operators
and the impact of this new RFID system in these operators.
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Exploração de espaços de parâmetros de modelos biológicos sob diferentes paradigmas estatísticos / Parameter space exploration of biological models under different statistical paradigmsOliveira, Andre Chalom Machado de 02 September 2015 (has links)
A formulação e o uso de modelos matemáticos complexos têm recebido grande atenção no estudo da ecologia nos últimos anos. Questões relacionadas à exploração de espaços de parâmetros destes modelos - executada de forma eficiente, sistemática e à prova de erros - são de grande importância para melhor compreender, avaliar a confiabilidade e interpretar o resultado destes modelos. Neste trabalho, apresentamos uma investigação de métodos existentes para responder as questões relevantes da área, com ênfase na técnica conhecida como Hipercubo Latino e com foco na análise quantitativa dos resultados, e realizamos a comparação entre resultados analíticos de incerteza e sensibilidade e resultados obtidos do Hipercubo. Ainda, examinamos a proposta de uma metodologia paralela baseada no paradigma estatístico da verossimilhança. O capítulo 1 introduz uma investigação a respeito dos conceitos históricos sobre a natureza da probabilidade, situando o conceito da verossimilhança como componente central da inferência estatística. O capítulo 2 (em inglês) traz uma revisão bibliográfica sobre o estado da arte em análises de incerteza e sensibilidade, apresentando dois exemplos de aplicação das técnicas descritas a problemas de crescimento populacional estruturado. O capítulo 3 examina a proposta de uma metodologia baseada na verossimilhança dos dados como uma abordagem integrativa entre a estimação de parâmetros e a análise de incerteza, apresentando resultados preliminares. Durante o progresso do presente trabalho, um pacote de funções na linguagem R foi desenvolvido para facilitar o emprego na prática das ferramentas teóricas expostas acima. Os apêndices deste texto trazem um tutorial e exemplos de uso deste pacote, pensado para ser ao mesmo tempo conveniente e de fácil extensão, e disponível livremente na internet, no endereço http://cran.r-project.org/web/packages/pse. / There is a growing trend in the use of mathematical modeling tools in the study of many areas of the biological sciences. The use of computer models in science is increasing, specially in fields where laboratory experiments are too complex or too costly, like ecology. Questions of efficient, systematic and error-proof exploration of parameter spaces are are of great importance to better understand, estimate confidences and make use of the output from these models. We present a survey of the proposed methods to answer these questions, with emphasis on the Latin Hypercube Sampling and focusing on quantitative analysis of the results. We also compare analytical results for sensitivity and uncertainty, where relevant, to LHS results. Finally, we examine the proposal of a methodology based on the likelihood statistical paradigm. Chapter 1 introduces a brief investigation about the historical views about the nature of probability, in order to situate the concept of likelihood as a central component in statistical inference. Chapter 2 (in English) shows a revision about the state-of-art uncertainty and sensitivity analyses, with a practical example of applying the described techniques to two models of structured population growth. Chapter 3 examines the proposal of a likelihood based approach as an integrative procedure between parameter value estimation and uncertainty analyses, with preliminary results. During the progress of this work, a package of R functions was developed to facilitate the real world use of the above theoretical tools. The appendices of this text bring a tutorial and examples of using this package, freely available on the Internet at http://cran.r-project.org/web/packages/pse.
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Estimating the Effectiveness of City Connects on Middle School OutcomesAn, Chen January 2015 (has links)
Thesis advisor: Henry I. Braun / City Connects is a school-based model that identifies the strengths and needs of every student and links each child to a tailored set of intervention, prevention, and enrichment services in the school or community. The purpose of this study was to conduct a comprehensive evaluation of the City Connects treatment effects on academic performance (both MCAS scores and grade point average (GPA) grades) in middle school using student longitudinal records. Parallel analyses were conducted: one evaluated the City Connects elementary intervention (serving kindergarten to fifth grades) and the other one evaluated the City Connects middle school intervention (serving sixth to eighth grades). A series of two-level hierarchical linear models with middle school achievement scores adjusted and/or propensity score weights applied were used to answer the research questions of interest. In addition, to make a causal inference, a sensitivity analysis was conducted to examine whether or not the estimated treatment effects resulted from the first two analyses were robust to the presence of unobserved selection bias. The results showed that students who were exposed to the City Connects elementary intervention significantly outperformed their counterparts, who graduated from the comparison elementary schools, on academic achievement in all middle school grades. However, in the case of the City Connects intervention schools that served middle school grades, since all students only received a maximum of one year of City Connects middle school intervention, it was still too soon to expect any significant changes. Moreover, the estimated treatment effects of the City Connects elementary intervention were only mildly sensitive to the presence of some forms of hidden bias, which made the causal inference of City Connects on middle school academic achievement quite plausible. / Thesis (PhD) — Boston College, 2015. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Research, Measurement and Evaluation.
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Procedimento para análise de sensibilidade do Programa HDM-4 / Procedure for sensitivity analysis of the HDM-4 softwareNunes, Diego Frinhani 13 April 2012 (has links)
A presente dissertação teve como objetivos principais delinear um procedimento de análise de sensibilidade que possa ser utilizado de forma ampla por usuários do programa computacional de gerência de pavimentos HDM-4 e analisar a influência de modificações no cenário pré-definido no estudo de caso, notadamente considerações de projeto e de tráfego. A escolha do Método dos Efeitos Elementares foi precedida por uma revisão bibliográfica sobre análise de sensibilidade, sendo que o procedimento foi delineado com um estudo de caso que partiu de um cenário pré-definido (rodovia de pista simples e pavimento asfáltico sobre base granular) e fez a análise da variação de 61 fatores, em 300 trajetórias, totalizando 18.600 simulações no programa HDM-4. Os resultados deste estudo indicaram que a utilização de uma amostra com 30 trajetórias é adequada, pois aumentar este número não acarreta ganhos significativos e a sua diminuição ocasiona prejuízos. Com o procedimento delineado, passou-se à verificação de impactos que a modificação dos cenários pré-definidos para a análise gerariam, ou seja, se a modificação de fatores que não estão no grupo de 61 fatores em estudo interferiria no resultado final do procedimento. Foram estudadas modificações nas considerações de projeto (Taxa de Desconto Monetário Anual e Período de Análise) e nas considerações de tráfego (Percentual de Veículos Comerciais e da Taxa de Crescimento Anual do Tráfego), com os resultados evidenciando que ambas as modificações influem no resultado final da análise de sensibilidade, sendo que as modificações nas considerações de tráfego se mostraram mais influentes que as modificações nas considerações de projeto. Complementarmente, foi feita uma análise de sensibilidade pelo Método dos Efeitos Elementares, com 250 trajetórias, que identificou como os três fatores mais influentes na análise econômica do programa HDM-4, dentro do universo estudado, o Volume Diário Médio Anual de Veículos Motorizados, o Fator de Calibração para a Progressão da Irregularidade Longitudinal e o Fator de Calibração para a Razão do Número Estrutural Ajustado das Estações Úmida e Seca. / This Master of Science Dissertation aimed to outline a procedure for sensitivity analysis that can be widely used by computer program of pavement management HDM-4 users. It also aimed to analyze the influence of changes in the pre-defined scenario of the case study, especially design and traffic considerations. The choice of the Elementary Effects Method was preceded by a literature review on sensitivity analysis, and the procedure was outlined with a case study that came from a pre-defined scenario (two lane standard and asphalt pavement on granular base) and variations of 61 factors, considering 300 trajectories, in a total of 18,600 simulations in HDM-4 program. The results indicated that the use of a sample with 30 trajectories is appropriate, because increasing this number does not cause significant gains and reducing it can harm the analysis. With the procedure outlined, it was checked if changes in factors that are not in the group of 61 studied factors can interfere with the end result. Thus, changes in design (Discount Rate and Period Annual Monetary Analysis) and traffic (Percentage of Commercial Vehicle and Annual Growth Rate of Traffic) considerations affected the final result the sensitivity analysis, and the changes in traffic considerations were more influential than changes in design considerations. In addition, it was conducted a sensitivity analysis by the Elementary Effects Method, with 250 trajectories, which identified as the three most influential factors in the economic analysis of HDM-4 program, within the universe studied, the Annual Average Daily Traffic of Automobiles, the Calibration Factor for the Progression of Longitudinal Roughness and the Calibration Factor for the Ratio of Adjusted Structural Number Wet and Dry Seasons.
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Känslighetsanalys vid energiberäkningar : Analys och tillämpning av metoder för känslighetsanalys av osäkra parametrar vid energiberäkningar i IDA ICE / Sensitivity analysis for energy calculations : Analysis and application of methods for sensitivity analysis of uncertain parameters in energy calculations with IDA ICELindgren, Emil January 2019 (has links)
Det blir allt viktigare att bygga energieffektivt och EU:s direktiv om energiprestanda har gjort att hårdare krav har införts i Boverkets byggregler (BBR). Detta har gjort att högre krav ställs på noggrannheten vid energiberäkningar i projekteringsfasen av ett byggprojekt. Vid en energiberäkning görs en rad inställningar och antaganden kring parametrar kopplade till byggnadens olika system, klimatskalet, samt det mänskliga beteendet i byggnaden. Det är vanligt att osäkerheter förekommer kring dessa parameterinställningar och detta kan i sin tur orsaka osäkerheter i beräkningsresultatet. För att undersöka hur stor inverkan osäkra parametrar har på beräkningsresultatet kan olika metoder av känslighetsanalys tillämpas. Syftet med detta arbete var att ta fram och tillämpa en metod för att genomföra en omfattande känslighetsanalys av osäkra parametrar vid energiberäkningar med simuleringsverktyget IDA ICE. Vidare gjordes en utvärdering över känslighetsanalysens roll i samband med energiberäkningar och hur resultaten kan användas för att förklara skillnader i projekterad och verklig energianvändning för en fastighetsägare. De inledande förberedelserna resulterade i en metod för global känslighetsanalys vid energiberäkningar i IDA ICE som låg till grund för större delen av detta arbete. Metoden använder sig av standardiserade regressionskoefficienter som känslighetsindikatorer och dessa beräknades genom att tillämpa Monte Carlo-simuleringar och multipel linjär regressionsanalys. Även en enklare metod för lokal känslighetsanalys vid energiberäkningar i IDA ICE undersöktes. Ett antal olika fall studerades i detta arbete och för samtliga fall undersöktes parametrarnas inverkan på den totala energianvändningen och primärenergitalet. En byggnadsmodell skapades över en byggnad i Umeå med fjärrvärme som uppvärmningskälla. För denna byggnadsmodell gjordes Monte Carlo-simuleringar och känslighetsanalys för basfallet, ett fall med bergvärme som uppvärmningskälla och ett fall där verksamheten förändrades. Klimatförutsättningarnas betydelse undersöktes genom att använda samma byggnadsmodell vid alternativa geografiska placeringar och genomföra känslighetsanalyser med den framtagna metoden. Förändringar i verksamheten, uppvärmningskällan och klimatet, visade sig alla påverka parametrarnas inverkan på beräkningsresultaten. En slutsats som gick att dra från resultaten var att osäkerheter i parametrar kopplade till byggnadsmodellernas värme- och ventilationssystem hade stor inverkan på beräkningsresultaten jämfört med de andra parametrarna. Även köldbryggornas specifika värmeförlustfaktor visade sig ha stor inverkan. Parametrar kopplade till mänskligt beteende hade även de relativt stor inverkan medan parametrarna kopplade till klimatskalets U-värden i de flesta fall visade sig ha mindre inverkan än de andra parametrar som undersöktes. / To build energy efficient buildings are becoming more important and as a response to the Energy Performance of Buildings Directive from the EU, harder requirements have been introduced into Boverket's building regulations (BBR). Higher demands are therefore placed on accuracy in energy calculations during the design phase of a building. When performing the energy calculations several parameter settings and assumptions are made that are linked to the building systems, envelope and the human behaviour inside the building. It is common that uncertainties occur around these parameter settings and this can often cause uncertainties in the calculation result. Different methods of sensitivity analysis can be applied to investigate which impact uncertain parameters have on the calculation results. The purpose of this master thesis was to develop and apply a method for computing a comprehensive sensitivity analysis of uncertain parameters in energy calculations with the simulation tool IDA ICE. Furthermore, an evaluation was made of the role of sensitivity analysis in combination with energy calculations and how the results can be used to explain differences in predicted and actual energy use for a property owner. The initial preparations resulted in a method for global sensitivity analysis for energy calculations in IDA ICE, which was the basis for the most part of this thesis. This method uses the standardized regression coefficients as sensitivity indices, which was calculated by applying Monte Carlo simulations and multiple linear regression. A simpler method for local sensitivity analysis was also investigated. In this thesis, a number of different cases were studied and for all of them, the influence of the parameters on the total energy use and the primary energy number was investigated. A building model was created for a building located in Umeå with district heating as heating source. For this building model, Monte Carlo simulations and sensitivity analysis were executed for the base case, a case with geothermal energy as heating source, and a case where the building was used as office spaces. The importance of climate conditions was investigated by using the same building model in alternative geographical locations and conduct sensitivity analysis with the developed method. Changes in operations, the heating source and the climate, all affected the influence of the parameters on the calculation results. One conclusion that could be made from the results was that uncertainties in parameters linked to the building models' heating and ventilation systems had a great impact on the calculation results compared to the other parameters. Also, the specific heat transfer coefficient of the thermal bridges was among the parameters with the greatest influence. The parameters linked to human behaviour also had a relatively large influence while parameters linked to the building envelope in most cases were found to have less influence than the other parameters examined.
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