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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.
11

Effektiva team i projektmiljöer : En kvalitativ studie om GDQ som projektledningsverktyg för att utveckla projektteam / Efficient teams in project environments : A qualitative study exploring GDQ as an instrument to develop project teams

Jansson, Erica January 2022 (has links)
Studien syftar till att få en förståelse för Group Development Questionnaire (GDQ) som projektledningsverktyg, hur det kan användas för att utveckla team samt vad utvecklingen kan leda till hos teamen. För att besvara syftet har tre frågeställningar upprättats: Hur upplevs GDQ som verktyg? Vad underlättar användandet av GDQ vid utveckling av team? och Hur upplevs team som har utvecklats utifrån en GDQ-mätning? En kvalitativ metod med semistrukturerade intervjuer valdes för genomförandet av studien och bidrog till ett resultat med tre centrala teman: Det var väl inte så farligt, Klara, färdiga...Vilket håll ska vi åt? och Hur går det för oss?  Det var väl inte så farligt belyser vikten av information för att minska motstånd och skapa en trygghet och nyfikenhet i teamutvecklingsprocessen. Klara, färdiga... Vilket håll ska vi åt? lyfter att teamet är det centrala i teamutvecklingsprocessen och Hur går det för oss? beskriver vad teamutvecklingen med GDQ som instrument upplevs leda till hos teamen. Studiens slutsatser är att GDQ är ett bra verktyg för att skapa en insikt och medvetenhet hos teamet, men att utvecklingen sker när teamet tar tag i områdena som framkommer av GDQ-mätningen och aktivt arbetar med dem. Information, motivation och vilja hos teamet är grundläggande för att utvecklingen ska ske. Teamutvecklingen leder till mer högfungerande team, med bättre kommunikationsstrukturer och ett mer effektivt samarbete. / The purpose of this study is to get an understanding of the Group Development Questionnaire (GDQ) as an instrument for project management, how it can be used to develop teams and what the team development process may result in. To answer this, three research questions have been formulated: What is the experience of GDQ as an instrument? What facilitates the use of GDQ in the development of teams? and How are teams that have been developed using GDQ perceived? A qualitative method with semi-structured interviews was used in this study, which led to a result with three central themes: That wasn’t so bad, Ready, set... Which way are we going? and How are we doing?  That wasn’t so bad illustrates the importance of information to reduce resistance and create a feeling of safety and curiosity in the process of team development. Ready, set... Which way are we going? shows that the team is the center of the team development process and How are we doing? describes what the team development with GDQ as an instrument can lead to in teams. The conclusion of this study is that GDQ is an adequate instrument for creating a realization and awareness in teams, but the key to team development lies with the team using the information to actively work with their development. Information, communication and motivation are key elements for team development to take place. Team development using GDQ leads to higher functioning teams, with better communication structures and a more efficient collaboration.
12

Modelling and simulation of membrane bioreactors for wastewater treatment

Janus, Tomasz January 2013 (has links)
The work presented in this thesis leads to the formulation of a dynamic mathematical model of an immersed membrane bioreactor (iMBR) for wastewater treatment. This thesis is organised into three parts, each one describing a different set of tasks associated with model development and simulation. In the first part, the Author qualitatively and quantitatively compares various published activated sludge models, i.e. models of biochemical processes associated with bacterial growth, decay, lysis and substrate utilisation in activated sludge systems. As the thesis is focused on modelling membrane bioreactors (MBRs) which are known to experience membrane fouling as a result of adsorption of biopolymers present in the bulk liquid onto and within the membrane, all activated sludge models considered in this thesis are able to predict, with various levels of accuracy, the concentrations of biopolymeric substances, namely soluble microbial products (SMP) and extracellular polymeric substances (EPS). Some of the published activated sludge models dedicated to modelling SMP and EPS kinetics in MBR systems were unable to predict the SMP and EPS concentrations with adequate levels of accuracy, without compromising the predictions of other sludge and wastewater constituents. In other cases, the model equations and the assumptions made by their authors were questionable. Hence, two new activated sludge models with SMP and EPS as additional components have been formulated, described, and simulated. The first model is based on the Activated Sludge Model No. 1 (ASM1) whereas the second model is based on the Activated Sludge Model No. 3 (ASM3). Both models are calibrated on two sets of data obtained from a laboratory-scale system and a full-scale system and prove to be in very good agreement with the measurements. The second part of this thesis explains the development of two membrane fouling models. These models are set to describe the loss of membrane permeability during filtration of various solutions and suspensions. The main emphasis is placed on filtration of activated sludge mixtures, however the models are designed to be as general as feasibly possible. As fouling is found to be caused by a large number of often very complex processes which occur at different spatial as well as temporal scales, the two fouling models developed here have to consider a number of significant simplifications and assumptions. These simplifications are required to balance the model's accuracy, generality and completeness with its usability in terms of execution times, identifiability of parameters and ease of implementation in general purpose simulators. These requirements are necessary to ascertain that long term simulations as well as optimisation and sensitivity studies performed in this thesis either individually on fouling models or on the complete model of a MBR can be carried out within realistic time-scales. The first fouling model is based on an idea that fouling can be subdivided into just two processes: short-term reversible fouling and long-term irreversible fouling. These two processes are described with two first order ordinary differential equations (ODEs). Whilst the first model characterises the membrane filtration process from an observer's input-output point of view without any rigorous deterministic description of the underlying mechanisms of membrane fouling, the second model provides a more theoretical and in-depth description of membrane fouling by incorporating and combining three classical macroscopic mechanistic fouling equations within a single simulation framework. Both models are calibrated on a number of experimental data and show good levels of accuracy for their designated applications and within the intended ranges of operating conditions. In the third part, the first developed biological model (CES-ASM1) is combined with the behavioural fouling model and the links between these two models are formulated to allow complete simulation of a hollow fibre (HF) immersed membrane bioreactor (iMBR). It is assumed that biological processes affect the membrane through production of mixed liquor suspended solids (MLSS), SMP and EPS which cause pore blockage, cake formation, pore diameter constriction, and affect the specific cake resistance (SCR). The membrane, on the other hand, has a direct effect on the bulk liquid SMP concentration due to its SMP rejection properties. SMP are assumed to be solely responsible for irreversible fouling, MLSS is directly linked to the amount of cake depositing on the membrane surface, whereas EPS content in activated sludge affects the cake's SCR. Other links provided in the integrated MBR model include the effects of air scouring on the rate of particle back-transport from the membrane surface and the effects of MLSS concentration on oxygen mass transfer. Although backwashing is not described in great detail, its effects are represented in the model by resetting the initial condition in the cake deposition equation after each backwash period. The MBR model was implemented in Simulink® using the plant layout adopted in the MBR benchmark model of Maere et al. [160]. The model was then simulated with the inputs and operational parameters defined in [36, 160]. The results were compared against the MBR benchmark model of Maere et al. [160] which, contrary to this work, does not take into account the production of biopolymers, the membrane fouling, nor any interactions between the biological and the membrane parts of an MBR system.
13

Understanding what factors influence a student's initial and developing choices on a course combining academic and vocational features : the case of BTEC Level 3 Science

Hutchinson, Rowley January 2016 (has links)
Why do students choose to study particular courses and what is the impact of these choices on their later progression? Quite often the reason for the choice appears to be obvious and straightforward, and their after course trajectory is already determined. The education system has, what some may view as an easy to follow progression route when students reach the end of Key Stage 4, i.e. GCSE to A level, and then university for those who meet the criteria. With A levels considered by many to be the 'gold standard', there is probably no expectation by schools, parents and students that they will do anything else. But what about those who may not meet the criteria and A levels may not be the most appropriate progression route for them? This thesis examines the factors that influence the choices made by students who have decided to study a course other than A level. This is done through longitudinal case studies derived from the use of questionnaires, focus groups and individual interviews using BTEC L3 Science as a vehicle. Four educational establishments agreed to participate in the research to varying degrees, with one establishment providing the participants who provided the case studies. Many previous studies that have investigated student choice have often done so from either the perspective of structural factors or individual agency, but not usually both. Hemsley-Brown and Fosketts' 2001 Integrated Model of Educational Choice has been used to provide a theoretical framework as it allows consideration of both structural factors and individual agency. The model was used at two different points in the research, but in a different way at each point. The result was a series of individual stories that gave an insight into the factors that influence student choice and also how the balance of power in the decision making process shifted in favour of the student as they progressed through the course. At the start of the course structural factors such as the systems that exist within education had a significant role in the choice of course for the students, to the point where it was effectively a 'non-choice' for them. By the end of the course individual agency played a significant role and the students were able to adapt and make the systems work for them to enable them to make the best possible choices to meet their own needs.
14

Desenvolvimento e aplicação de metodologia para estudos de simulação dinâmica na cadeia do minério de ferro. / Development and application methodology for dynamic simulation studies of the iron ore supply chain.

Cremonese, Dennis Travagini 07 February 2014 (has links)
Este estudo propõe uma metodologia para a simulação dinâmica da cadeia de produção mineral. A metodologia proposta permite que modelos complexos sejam construídos rapidamente e com precisão, reduzindo os custos de estudos nas fases de projeto e possibilitando reduções mais expressivas nos custos de implantação e operação do empreendimento. A metodologia proposta abrange todas as etapas de estudo desde a formulação do problema a ser analisado até a implementação dos resultados e foi aplicada em um projeto, durante as fases de FEL 2 e 3 (Projeto Conceitual e Básico). O projeto estudado consiste da produção de produtos de minério de ferro de uma empresa de mineração em Corumbá/MS, incluindo lavra, beneficiamento e transporte do minério beneficiado por ferrovia até o porto de Santos/SP. São apresentadas as premissas, dados de entrada e conceitos para criação de um modelo que integre Pátio de Estocagem da Usina de Beneficiamento, Ferrovia e Porto, além dos dados de saídas do modelo necessários para avaliação e suas análises. Com base nos resultados obtidos foram identificados as ações que podem ser tomadas para o aumento da eficiência do trabalho de modelagem. A aplicação da metodologia proposta permitiu comprovar que um modelo integrado de simulação, envolvendo as diferentes atividades da cadeira de produção mineral, oferece uma visão global dos processos envolvidos e facilita a tomada de decisão. / This study proposes a methodology for dynamic simulation of the mineral supply chain. The proposed methodology allows complex models to be built quickly and accurately, reducing the costs of studies in the design phases and enabling more substantial reductions in the costs of implementation and operation of the enterprise. The proposed methodology covers all stages of study since the problem formulation to be analyzed until the results implementation and was applied in a project, during the phases of FEL 2 and 3 (Pre-Feasibility and Feasibility Study). The project studied consists of the production of iron ore products from a mining company in Corumbá/MS, including mining, beneficiation and transportation of the processed ore by rail to the port of Santos/SP. Assumptions, input data and concepts to create a model that integrates the Stockyard of the Beneficiation Plant, Rail and Port are presented, beyond the outputs data of the model necessary for the assessment and analysis. Based on the results obtained were identified actions that can be taken to increase the efficiency of modeling work. The application of the proposed methodology allowed to demonstrate that an integrated simulation model, involving different activities of the mineral supply chain, provides an overview of the involved process and facilitates decision making.
15

Impact of Climate Change on Groundwater Reserves

Goderniaux, Pascal 24 February 2010 (has links)
Estimating the impacts of climate change on groundwater represents one of the most difficult challenges faced by water resources specialists. One difficulty is that simplifying the representation of the hydrological system, or using too simple climate change scenarios often leads to discrepancies in projections. Additionally, these projections are affected by uncertainties from various sources, and these uncertainties are not evaluated in previous studies. In this context, the objective of this study is to provide an improved methodology for the estimation of climate change impact on groundwater reserves, including the evaluation of uncertainties. This methodology is applied to the case of the Geer basin catchment (480 km²) in Belgium. A physically-based surface-subsurface flow model has been developed for the Geer basin with the finite element model HydroGeoSphere. The simultaneous solution of surface and subsurface flow equations in HydroGeoSphere, as well as the internal calculation of the actual evapotranspiration as a function of the soil moisture at each node of the defined evaporative zone, improve the representation and calibration of interdependent processes like recharge, which is crucial in the context of climate change. Fully-integrated surface-subsurface flow models have recently gained attention, but have not been used in the context of climate change impact studies. This surface-subsurface flow model is combined with advanced climate change scenarios for the Geer basin. Climate change simulations were obtained from six regional climate model (RCM) scenarios assuming the SRES A2 greenhouse gases emission (medium-high) scenario. These RCM scenarios were statistically downscaled using two different methods: the 'Quantile Mapping Biased Correction' technique and a 'Weather Generator' technique. Both of them are part of the most advanced downscaling techniques. They are able to apply corrections not only to the mean of climatic variables, but also across the statistical distributions of these variables. This is important as these distributions are expected to change in the future, with more violent rainfall events, separated by longer dry periods. The 'quantile mapping bias-correction' technique generate climate change time series representative of a stationary climate for the periods 2011-2040, 2041-2070 and 2071-2100. The 'CRU' weather generator is used to generate a large number of equiprobable scenarios simulating full transient climate change between 2010 and 2085. All these scenarios are applied as input of the Geer basin model. The uncertainty is evaluated from different possible sources. Using a multi-model ensemble of RCMs and GCMs enables to evaluate the uncertainty linked to climatic models. The application of a large number of equiprobable climate change scenarios, generated with the 'weather generator', as input of the hydrological model allows assessing the uncertainty linked to the natural variability of the weather. Finally, the uncertainty linked to the calibration of the hydrological model is evaluated using the computer code 'UCODE_2005'. The climate change scenarios for the Geer basin model predict hotter and drier summers and warmer and wetter winters. Considering the results of this study, it is very likely that groundwater levels and surface flow rates in the Geer basin will decrease. This is of concern because it also means that groundwater quantities available for abstraction will also decrease. However, this study also shows that the uncertainty surrounding these projections is relatively large and that it remains difficult to state on the intensity of the decrease.
16

The Analysis of Seasonally Varying Flow in a Crystalline Rock Watershed Using an Integrated Surface Water and Groundwater Model

Randall, Jefferey January 2005 (has links)
Researchers, explorers, and philosophers have dedicated many lifetimes attempting to discover, document, and quantify the vast physical processes and interactions occurring in nature. Our understanding of physical processes has often been reflected in the form of numerical models that assist academics in unraveling the many complexities that exist in our physical environment. To that end, integrated surface water-groundwater models attempt to simulate the complex processes and relationships occurring throughout the hydrologic cycle, accounting for evapotranspiration and surface water, variably saturated groundwater, and channel flows. <br /><br /> The Bass Lake watershed is located in the Muskoka district of Ontario, within a crystalline rock environment consistent with typical Canadian Shield settings. Numerous data collection programs and methods were used to compile environmental and field-scale datasets. The integrated surface water-groundwater model, HydroGeoSphere (Therrien et al. , 2005), was used for all Bass Lake watershed simulation models. <br /><br /> Simulation results were compared to expected trends and observed field data. The groundwater heads and flow vector fields show groundwater movement in expected directions with reasonable flow velocities. The subsurface saturation levels behave as expected, confirming the evapotranspiration component is withdrawing groundwater during plant transpiration. The surface water depths and locations of water accumulation are consistent with known and collected field data. The surface waters flow in expected directions at reasonable flow speeds. Simulated Bass Lake surface elevations were compared to observed surface water elevations. Low overland friction values produced the most accurate Bass Lake elevations, with high overland friction values slightly overestimating the Bass Lake water level throughout the simulation period. Fluid exchange between surface water and groundwater domains was consistent with expected flux rates. The integrated surface water-groundwater model HydroGeoSphere ultimately produced acceptable simulations of the Bass Lake model domain.
17

The Analysis of Seasonally Varying Flow in a Crystalline Rock Watershed Using an Integrated Surface Water and Groundwater Model

Randall, Jefferey January 2005 (has links)
Researchers, explorers, and philosophers have dedicated many lifetimes attempting to discover, document, and quantify the vast physical processes and interactions occurring in nature. Our understanding of physical processes has often been reflected in the form of numerical models that assist academics in unraveling the many complexities that exist in our physical environment. To that end, integrated surface water-groundwater models attempt to simulate the complex processes and relationships occurring throughout the hydrologic cycle, accounting for evapotranspiration and surface water, variably saturated groundwater, and channel flows. <br /><br /> The Bass Lake watershed is located in the Muskoka district of Ontario, within a crystalline rock environment consistent with typical Canadian Shield settings. Numerous data collection programs and methods were used to compile environmental and field-scale datasets. The integrated surface water-groundwater model, HydroGeoSphere (Therrien et al. , 2005), was used for all Bass Lake watershed simulation models. <br /><br /> Simulation results were compared to expected trends and observed field data. The groundwater heads and flow vector fields show groundwater movement in expected directions with reasonable flow velocities. The subsurface saturation levels behave as expected, confirming the evapotranspiration component is withdrawing groundwater during plant transpiration. The surface water depths and locations of water accumulation are consistent with known and collected field data. The surface waters flow in expected directions at reasonable flow speeds. Simulated Bass Lake surface elevations were compared to observed surface water elevations. Low overland friction values produced the most accurate Bass Lake elevations, with high overland friction values slightly overestimating the Bass Lake water level throughout the simulation period. Fluid exchange between surface water and groundwater domains was consistent with expected flux rates. The integrated surface water-groundwater model HydroGeoSphere ultimately produced acceptable simulations of the Bass Lake model domain.
18

The Construction of Cross Market Stock Risk Model - With Application in Taiwan¡AChina and Singapore

Chang, Chia-hua 14 November 2011 (has links)
This study constructs a cross-market risk model based upon local multi-factor risk models of Taiwan, China and Singapore equity markets. This model allows each local market to adopt different local factors rather than force all local markets to use one parsimonious set of factors. We employ the world, country, industry, and global risk factors to build a structural model which could explain the relationship between local factors across market by further decomposing local factor returns. Therefore, this model could provide both in-depth and broad coverage analysis of international equity portfolios. Furthermore, we build a simple portfolio and its corresponding benchmark to illustrate the usage of our model. Once the contents of a portfolio are decided, this model could provide not only the risk estimation and decomposition in advance but also the performance attribution compared with the benchmark after the portfolio is realized. The analytical viewpoint could also easily change with different numeraire perspectives. The result demonstrates that this model is practical and flexible for international equity portfolio analysis.
19

A comparison of variables affecting three kinds of environmental intention held by members of environmental groups in Taiwan

Cheng, Shih-i 12 April 2004 (has links)
In Taiwan, the environmental protection actions that people usually take are "physical actions", such as picking up litter, sorting trash, installing household resource-conserving devices. Other kinds of actions¡Xe.g., persuasive actions, civic action (such as signing for environmental causes, petitioning and lobbying) ¡Xare far less common. However, the latter actions, especially civic actions, are more effective than physical actions in pushing the government to adopt proenvironment policies and thus have more far-reaching impacts. This study thus focused on three civic and persuasive actions¡Xsigning for environmental causes, lobbying, and being an ecotourism interpreter. And since these actions are usually taken as a group action (people do so either because they are members of environmental groups or other NGOs, or because they join the actions of these organizations) , this study took environmental group members as its target population. A survey of intentions regarding the above three kinds of actions was made, with 210 environmental group members as respondents. Two models were used to predict these behaviors. One was the theory of planned behavior (TPB) proposed by Ajzen (1988, 1991) , the other one was an integrated model based on theories from three disciplines¡Xsocial psychology, environmental education, public health¡Xand literatures of society mobilization. The integrated model contained 8 predictors, 4 of which were from the TPB (the subjective norm variable in the TPB was further split into 2 variables: subjective norm with respect to family members, subjective norm with respect to community members) . The other 4 variables were environmental moral obligation, environmental attitude, response efficacy and collective efficacy. Results showed that both the TPB and integrated models could predict all three kinds of environmental intention (R2 > .49 for each model and intention) . The integrated model, however, was not better than the TPB model in predicting the intention to lobby. And it was only a little better in predicting the intentions to sign and to be an interpreter. Implications of these results and suggestions for environmental groups and environmental education organizations were discussed.
20

Study on Landslide Dam Failure Due to Sliding and Overtopping / 滑りおよび越流による天然ダムの決壊に関する研究 / スベリ オヨビ エツリュウ ニ ヨル テンネン ダム ノ ケッカイ ニ カンスル ケンキュウ

Awal, Ripendra 24 September 2008 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14136号 / 工博第2970号 / 新制||工||1441(附属図書館) / 26442 / UT51-2008-N453 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 中川 一, 教授 関口 秀雄, 教授 藤田 正治 / 学位規則第4条第1項該当

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