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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.
1

Systémové myšlení v rámci edukačního procesu

Exnarová, Anna January 2007 (has links)
Tato práce se věnuje systémovému myšlení a především jeho kontextu k pedagogice. Cílem práce je poukázat na význam systémového myšlení z různých pohledů. Práce poskytuje přehled různých definic a přístupů, které autoři při práci v tomto oboru využívají. Současně je prezentována provázanost systémového myšlení s pojmy z pedagogiky a možné začlenění systémového myšlení do výuky. Součástí práce je prezentování Bathtub testů jako příkladu testů systémového myšlení, vyhodnocení výsledků těchto testů, které byly studentům magisterského studia na katedře systémové analýzy VŠE v Praze předkládány v rámci kurzu Systémová dynamika.
2

Význam systémového myšlení a schopnost jeho aplikace studenty Informačního managementu / Importance of systems thinking and capability of its application by students of Information management

Svoboda, Roman January 2012 (has links)
The diploma thesis deals with the indispensability of the systems thinking and its testing. Theoretical analysis of the subject as the first part of the thesis points to show the importance of the systems thinking in everyday life, the definition of essential skills within the systems thinking and typical mistakes we commit in the thinking processes. The theoretical analysis puts the accent on justification of the systems thinking importance in the scope of information management. Another part of the thesis is focused on globally used examples in testing processes of the systems thinking which are supplied with newly arised questions in this thesis. The last part of the thesis contains a detailed analysis of the systems thinking skills among students of Information Management. Their results are compared with two other result samples gained from testing of other students of the University of Economics.
3

Design hydromasážní vany pro horní končetiny / Design of Hydromassage Bathtub for Upper Limbs

Vávra, Marek January 2019 (has links)
The topic of this thesis is design of hydrotherapy bathtub for upper limbs that reacts mainly to ergonomic weaknesses of current solutions. Created design concept is mainly focused on users comfort. Its appearance reflects the environment of medical and rehabilitation facilities.
4

Monitoring and modeling water quality at the C.W. Young Regional Reservoir

Dye, Daniel Robert 01 June 2006 (has links)
This work explores the relationship between nutrient loading and changes in water quality in a sub-tropical, above-ground, off-stream municipal water supply reservoir, the C.W. Bill Young Regional Reservoir. The three source waters for the reservoir have varied but high levels of nutrients such as phosphorus and nitrogen. In other reservoirs, these nutrients have been linked to deterioration of water quality and increased expense in water treatment. The need to minimize excess nutrients results led to the primary research question: what allocation of withdrawals from the three sources will minimize the deterioration of water quality? To answer this question, the relationship between nutrient and other water quality data, such as temperature,phosphorus, chlorophyll a, Secchi depth, and trophic state indices were explored. Results indicate that temperature had a correlation with observed water quality. 27.9% of the variability in trophic state index as a function of Chlorophyll a was correlated with average temperature at one foot below water level. Correlation and regression models were developed using available time-series of linear and log-transformed water quality data to predict Chlorophyll a response. The parameters used in the model were selected from correlation matrices and from the P value in the multiple regression. The models developed were significant at P < 0.05. In the developed models, temperature was found to have greater predictive strength than nutrients indicating that this reservoir may be more strongly influenced by season and light than by nutrient limitation. Lastly, the US Army Corps of Engineers' eutrophication model, BATHTUB, was used to simulate different loading conditions and trophic response. The model results indicate that use of water the middle pool or lower pool of the Tampa Bypass Canal yield similar trophic states with the middle pool slightly lower. Use of water from the Alafia River yielded the highest trophic state and would be expected to have negative impacts on water quality.
5

Q-weibull generalized renewal process with reliability applications

CORRÊA, Thaís Lima 21 February 2017 (has links)
Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-06-29T19:10:32Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Thaís Lima Corrêa.pdf: 1826347 bytes, checksum: 3e2a4eaa7d0d1c4c2e98d8d8e9bec071 (MD5) / Made available in DSpace on 2018-06-29T19:10:32Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Thaís Lima Corrêa.pdf: 1826347 bytes, checksum: 3e2a4eaa7d0d1c4c2e98d8d8e9bec071 (MD5) Previous issue date: 2017-02-21 / CAPES / Generalized Renewal Process (GRP) is a probabilistic model for repairable systems that can represent any of the five possible post-repair states of an equipment: as new condition, as old condition, as an intermediate state between new and old conditions, a better condition and a worse condition. GRP is often coupled with the Weibull distribution to model the equipment failure process and the Weibull-based GRP is able to accommodate three types of hazard rate functions: monotonically increasing, monotonically decreasing and constant. This work proposes a novel approach of GRP based on the q-Weibull distribution, which has the Weibull model as a particular case. The q-Weibull distribution has the capability of modeling two additional hazard rate behaviors, namely bathtub-shaped and unimodal curves. Such flexibility is related to a pair of parameters that govern the shape of the distribution, instead of a single parameter as in the Weibull model. In this way, the developed q-Weibull-based GRP is a more general framework that can model a variety of practical situations in the context of reliability and maintenance. The maximum likelihood problems associated with the qWeibull-based GRP using Kijima’s virtual age type I and II for the failure and time terminated cases are developed. The probabilistic and derivative-free heuristic Particle Swarm Optimization (PSO) is used to obtain the q-Weibull-based GRP paramaters’ estimates. The proposed methodology is applied to examples involving equipment failure data from literature and the obtained results indicate that the q-Weibull-based GRP may be a promising tool to model repairable systems. / O Processo de Renovação Generalizado (PRG) pode ser definido como um modelo probabilístico de sistemas reparáveis capaz de representar os cinco possíveis estados do sistema após o reparo: condição de um equipamento novo, condição de um equipamento antigo, um estado intermediário entre novo e antigo, melhor do que novo e pior do que antigo. O PRG costuma ser comumente empregado junto com a distribuição Weibull para a modelagem do processo de falhas dos equipamentos, no entanto, o modelo de GRP baseado na distribuição Weibull é capaz de considerar três comportamentos de taxa de falha: monotonicamente crescente, monotonicamente decrescente e constante. Este trabalho propõe uma nova abordagem para o PRG baseado na distribuição q-Weibull, que apresenta como um de seus casos particulares a distribuição Weibull. A distribuição q-Weibull apresenta a capacidade de modelar dois comportamentos de falha adicionais, denominadas curva da banheira e curva unimodal. Esta flexibilidade está relacionada a dois parâmetros que definem o formato da distribuição, ao invés de um único parâmetro como no caso da Weibull. Dessa forma, o modelo de PRG baseado na q-Weibull pode ser considerado uma estrutura mais geral de modelagem de uma variedade de situações práticas no contexto da confiabilidade e manutenção. São desenvolvidos estimadores de máxima verossimilhança para os casos de PRG baseada na distribuição q-Weibull sendo utilizadas as idades virtuais Kijima tipo I e II para os casos de dados censurados e não censurados. A heurística probabilística e livre de derivadas denominada Otimização via Nuvem de Partículas (Particle Swarm Optimization - PSO) é utilizada para obter os estimadores de máxima verossimilhança do modelo. O modelo proposto é aplicado a exemplos envolvendo falhas de equipamentos retirados da literatura e os resultados obtidos indicam que o PRG baseado na q-Weibull é uma ferramenta promissora na modelagem de sistemas reparáveis.
6

Nonhomogeneous Poisson Process Models with a Generalized Bathtub Intensity Function for Repairable Systems

Yan, Tianqiang January 2019 (has links)
No description available.
7

The Effects of Land Use and Contaminant Transport at a Proposed Reservoir Site in Smith County, Mississippi

Cherry, William Earl 12 May 2012 (has links)
This study investigates nutrient and contaminant transport within the Oakohay Creek watershed in order to (1) demonstrate the effects of land use on water quality, (2) model and predict the trophic state of the proposed reservoir given current nutrient loads, and (3) understand potential groundwater flow paths within the reservoir footprint. This study demonstrates that the current, large-scale poultry industry, though not statistically significant with a confidence of 95%, does have a negative impact on the surface water quality. The study also shows evidence for a eutrophic reservoir (TSI-P of 59.4 area-weighted mean) with an increased potential for nuisance algal growth in the northeast segment (TSI-P of 66.0). Dye tracing studies suggest the potential for groundwater flow out of the reservoir as a result of potential paleo-channels within the Glendon Limestone. This study concludes that the location on the Oakohay Creek is not suitable for the construction of a reservoir.
8

Modélisation expérimentale et numérique de l'écoulement au sein d'un système convertisseur de l'énergie de la houle / Physical and numerical model of the flow inside a wave energy converter

Fourestier, Gaspard 11 May 2017 (has links)
Cette thèse se focalise sur un système récupérateur de l’énergie des vagues qui est constitué d’un flotteur contenant des cuves partiellement remplis d’eau. Lorsque les vagues mettent en mouvement le flotteur, un tourbillon de type vidange apparaît dans une des cuve. Pour extraire l’énergie, une turbine, reliée à une génératrice, est plongée dans ce tourbillon. Tout d’abord, le tourbillon de vidange est étudié expérimentalement dans un contenant fixe. Les hauteurs d’eau et les vitesses du liquide sont mesurées. Ces vitesses sont estimées par vélocimétrie laser (LaserDoppler Velocimetry, LDV). Cet écoulement est modélisé numériquement en résolvant les équations de Navier-Stokes dans les deux phases (eau et air) par la méthode des volumes finis (avec le logiciel OpenFOAM). L’interface entre les deux phases est déterminée par la méthode des Volume of Fluid (VoF). Des comparaisons entre les résultats de ces deux approches sont menées. Ensuite, l’écoulement à l’intérieur du système houlomoteur est étudié en plaçant une maquette du dispositif sur un Hexapode (machine capable d’imposer des mouvements à la maquette à la manière d’un flotteur en mer). Les hauteurs d’eau et les efforts hydrodynamiques sur la maquette et, le cas échéant, la puissance électrique produite sont mesurés. Ces données sont comparées aux résultats d’un modèle numérique similaire à celui utilisé pour la première campagne expérimentale mais appliqué à ce dispositif. Enfin, l’influence de la turbine sur le reste du système est étudiée et son comportement en puissance est évalué pour différents mouvements imposés. Un premier modèle numérique de cette turbine est comparé aux données expérimentales. / This thesis focuses on the physical and numerical model of a wave energy converter (WEC). This device is made up of a buoy with compartments aboard partially filled with water. When the waves move the buoy, a bathtub vortex appears in one of these compartments. The energy is harvested with a turbine placed at the vortex’s center. First, the bathtub vortex is studied numerically and experimentally in a fixed compartment. Water levels are measured using acoustics sensors and water velocities are measured by Laser Doppler Velocimetry (LDV). This flow is modeled solving the Navier-Stokes equations in the two phases (air and water) with a finite volume method (with the software OpenFOAM). The interface is determined using the volume of fluid (VoF) method. Comparisons between experimental data and numerical data are presented. Afterwards, a second experimental campaign is conducted to study the complete flow inside the WEC. Therefore a model of the inside part of the WEC is fixed at the top of a Hexapod. This device can translate and rotate the model in the same way the waves would move a buoy. Water levels and hydrodynamic forces on the model are measured. When the turbine is there, the tension delivered by its generator is measured. This experimental device is modeled numerically. This model is closed to the first one. The results are compared with experimental data. Finally, a preliminary study of the turbine shows its influence on the general flow in the WEC and the evolution of the turbine power with the imposed motion. A first model of the turbine in a fixed compartment is presented and compared with experimental data.
9

Etude expérimentale et numérique des écoulements diphasiques dans la boîte à eau d’un véhicule automobile / Experimental and numerical investigation of two-phase flows in the cowl box of an automotive vehicle

Recoquillon, Yann 14 November 2013 (has links)
Cette thèse vise à améliorer le fonctionnement de la boîte à eau d’un véhicule automobile, organe destiné à évacuer l’eau de pluie et à alimenter l’habitacle en air propre et sec. Elle se concentre plus particulièrement sur le phénomène de tourbillon de vidange qui a pour effet de limiter le débit d’évacuation et d’augmenter le niveau d’eau dans la boîte. Cette hausse de niveau peut être source de problèmes allant de l’inconfort pour les occupants du véhicule jusqu’à une panne du boîtier de ventilation, chauffage et climatisation. Une étude expérimentale de l’écoulement est d’abord réalisée sur une géométrie simplifiée. La vélocimétrie par images de particules (PIV) et des mesures de niveau par sonde capacitive sont mises en oeuvre. A partir d’images obtenues par caméra rapide, un algorithme d’analyse d’images est développé pour mesurer le diamètre du noyau d’air au coeur du tourbillon. Ces techniques de mesure permettent d’étudier la structure du tourbillon et montrent qu’il existe une interaction entre le tourbillon et l’écoulement d’air destiné à la ventilation de l’habitacle. Cette interaction est liée à la dépression générée par l’écoulement d’air : elle modifie temporairement la structure du tourbillon et conduit à un nouvel état d’équilibre à un niveau inférieur au niveau initial. Un dispositif permettant de réduire efficacement le niveau d’eau en modifiant l’écoulement en amont du tourbillon est aussi étudié et a fait l’objet d’un dépôt de brevet. Des simulations numériques sont ensuite réalisées à l’aide du code de calcul OpenFOAM et reproduisent qualitativement l’écoulement observé expérimentalement. Bien que des différences existent sur la valeur du niveau d’eau, les dimensions et la position du noyau d’air sont correctement simulées. Enfin, les résultats expérimentaux et numériques sont comparés aux modèles de tourbillon de la littérature. / This thesis aims to improve the performance of the cowl box in automotive vehicles ; a system dedicated to draining rainwater and providing clean and dry air to the passenger compartment. This work places emphasis on the bathtub vortex phenomenon which leads to decreased drain rate and increased water level in the box. This increase can cause a variety of issues from passenger discomfort to the breakdown of the heating, ventilation and air conditioning unit. An experimental study of the flow was firstly conducted on a simplified geometry. Particle Image Velocimetry (PIV) and capacitive probe for water level measurement have been applied to study the flow structure. In addition, an image processing algorithm has been developped to measure the size of the air core with a fast camera. It enables to study the vortex structure and demonstrates that there is an interaction between the vortex and airflow intended for the ventilation of the passenger compartment. This interaction is caused by the depression created by the airflow which temporarily modifies the vortex structure and leads to a new equilibrium state at a lower water level. A device that allows the efficient reduction of the water level by modifying the upstream flow has also been studied. This device has been patented. Following the experimental aspect of the study, numerical simulations were generated using the OpenFOAM software package. Simulations qualitatively reproduce the flow which had been experimentally observed. Despite the difference on the water level, the size and position of the air core is correctly simulated. Simulation also demonstrates the existence of an airflow sucked through the drain in the air core. Lastly, the experimental and numerical results were compared to various vortex models existing in the literature.
10

Bytový dům "Vacek" / Apartment building "Vacek"

Vacek, Pavel January 2015 (has links)
I have designed the construction of a apartment building with multifunctional usage. A significant element is the internal automatic parking system, which is a relief for the residents of the house on a street crowded with parked cars. On the ground floor is a lucrative cafe with sitting area and two bowling lines. The house contains 18 housing units for 4-6 people. People are attracted by prestigious location with views of the city Brno on the dominant historical monuments and are attracted by a pleasant interior of the apartments, too. They are logically divided into 4 zones - day, night, working and relaxing. For relaxation, they may use the spacious balconies, terraces and a common area in the garden with children's play area. One part of this work is a focus on securing of construction pit and foundation of a building, which is almost a technical delicacy.

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