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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.
101

Posouzení rizik při provádění zatěžovacích zkoušek stavebních konstrukcí / Risk assessment in the implementation of load tests on building structures

Ešpandr, Jan January 2016 (has links)
This diploma thesis deals with the analysis of the risks during the executing of the loading tests of building constructions. The thesis focuses on the explanation of some of the terms in the field of risk management, the description of the individual types of loading tests of building constructions, the identification of the risks during the loading tests and their assessment. Analytical methods were used for assessing of the individual risks. Ishikawa diagrams were used for the basic identification of the risks. These risks were further assessed in the FMEA analysis and the results were filled in the Pareto charts. In conclusion of the practical part of the diploma thesis the HRA method was used for the more precise assessment of the human failure in the whole process of executing of the loading tests of building constructions.
102

Multiuživatelský systém pro podporu znovuvyužití materiálů / Multiuser System for Material Reusing

Kolarik, Petr January 2007 (has links)
This text is documentation for multi-access system, which supports recoverable materials. It deals with structure possibilities according to functional system specification and its implementation through the PHP together with using MySQL database system. It analyses a progress of system creation from ER diagram through use-case diagram to programming itself. This work shows how to design web advertisement system which enables an user to define personal multi-level views on data. This project might have been as basis for commerce project, which can check up usability designed structure of individual parts.
103

Theoretical analysis of the effects of bus operations on urban corridors and networks

Castrillon, Felipe 07 January 2016 (has links)
Bus systems have a large passenger capacity when compared to personal vehicles and thus have the potential to improve urban mobility. However, buses that operate in mixed vehicle traffic can undermine the effectiveness of the road system as they travel at lower speeds, take longer to accelerate and stop frequently to board and alight passengers. In traffic flow theory, buses are known as slow-moving bottlenecks that have the potential to create queue-spillbacks and thus increase the probability of gridlock. Currently, traditional metropolitan transportation planning models do not account for these negative effects on roadway capacity. Also, research methods that study multimodal operations are often simulated or algorithmic which can only provide specific results for defined inputs. The objective of this research is to model and understand the effects of bus operations (e.g., headway, number of stops, number of routes) on system performance (e.g. urban corridor and network vehicular capacity) using a parsimonious analytical approach with a few parameters.The models are built using the Macroscopic Fundamental Diagram (MFD) of traffic which provides aggregate measures of vehicle density and flow. Existing MFD theory, which accounts for corridors with only one vehicle class are extended to include network roadway systems and bus operations. The results indicate that buses have two major effects on corridors: the moving bottleneck and the bus short-block effect. Also, these corridor effects are expanded to urban networks through a vehicle density-weighted average. The models have the potential to transform urban multimodal operations and management as they provide a simple tool to capture aggregate performance of transportation systems.
104

ARCHITECTURAL CONSIDERATIONS FOR A VARIABLE BIT RATE DATA ACQUISITION TELEMETRY ENCODER

Lee, Jeffrey C. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Modern telemetry systems require flexible bit rate telemetry encoders in order to optimize mission formats for varying data rate requirements and/or signal to noise conditions given a fixed transmitter power. Implementing a variable bit rate telemetry encoder requires consideration of several possible architectural topologies that place different system requirements on data acquisition modules within the encoder in order to maintain adequate signal fidelity of sensor information. This paper focuses on the requirements, design considerations and tradeoffs associated with differing architectural topologies for implementing a variable bit rate encoder and the resulting implications on the encoder systems data acquisition units.
105

The Karma of Products : Exploring the Causality of Environmental Pressure with Causal Loop Diagram and Environmental Footprint

Laurenti, Rafael January 2016 (has links)
Environmental pressures from consumer products and mechanisms of predetermination were examined in this thesis using causal loop diagram (CLD) and life cycle assessment (LCA) footprinting to respectively illustrate and provide some indicators about these mechanisms. Theoretical arguments and their practical implications were subjected to qualitative and quantitative analysis, using secondary and primary data. A study integrating theories from various research fields indicated that combining product-service system offerings and environmental policy instruments can be a salient aspect of the system change required for decoupling economic growth from consumption and environmental impacts. In a related study, modes of system behaviour identified were related to some pervasive sustainability challenges to the design of electronic products. This showed that because of consumption and investment dynamics, directing consumers to buy more expensive products in order to restrict their availability of money and avoid increased consumption will not necessarily decrease the total negative burden of consumption. In a study examining product systems, those of washing machines and passenger cars were modelled to identify variables causing environmental impacts through feedback loops, but left outside the scope of LCA studies. These variables can be considered in LCAs through scenario and sensitivity analysis. The carbon, water and energy footprint of leather processing technologies was measured in a study on 12 tanneries in seven countries, for which collection of primary data (even with narrow systems boundaries) proved to be very challenging. Moreover, there were wide variations in the primary data from different tanneries, demonstrating that secondary data should be used with caution in LCA of leather products. A study examining pre-consumer waste developed a footprint metric capable of improving knowledge and awareness among producers and consumers about the total waste generated in the course of producing products. The metric was tested on 10 generic consumer goods and showed that quantities, types and sources of waste generation can differ quite radically between product groups. This revealed a need for standardised ways to convey the environmental and scale of significance of waste types and for an international standard procedure for quantification and communication of product waste footprint. Finally, a planning framework was developed to facilitate inclusion of unintended environmental consequences when devising improvement actions. The results as a whole illustrate the quality and relevance of CLD; the problems with using secondary data in LCA studies; difficulties in acquiring primary data; a need for improved waste declaration in LCA and a standardised procedure for calculation and communication of the waste footprint of products; and systems change opportunities for product engineers, designers and policy makers. / <p><strong>Jury committee</strong></p><p></p><p><strong>Henrikke Baumann, </strong>Associate Professor<strong></strong></p><p>Chalmers University of Technology</p><p>Department of Energy and Environment</p><p>Division of Environmental System Analysis</p><p></p><p><strong>Joakim Krook, </strong>Associate Professor</p><p>Linköpings Universitet</p><p>Department of Management and Engineering (IEI) / Environmental Technology and Management (MILJÖ)</p><p></p><p><strong>Karl Johan Bonnedal, </strong>Associate Professor</p><p>Umeå University</p><p>Umeå School of Business and Economics (USBE)</p><p></p><p><strong>Sofia Ritzén</strong>, Professor</p><p>KTH Royal Institute of Technology</p><p>School of Industrial Engineering and Management</p><p>Department of Machine Design</p><p>Integrated Product Development</p><p>QC 20160405</p><p></p>
106

Equilibrium Phase Behavior and Self-assemble Dynamics of a Continuous-Space Microphase Former

Zhuang, Yuan January 2016 (has links)
<p>The microphase segregation behavior, which exhibits periodic patterns on a mesoscale, has been found in many systems where it has demonstrated its extreme industrial usefulness in the diblock copolymer system. When studying more general isotropic colloidal systems, periodic microphases should ubiquitously emerge in systems for which short-range inter-particle attraction is frustrated by long-range repulsion~(SALR). The morphological richness of these phases makes them desirable material targets, but our relatively coarse understanding of even simple models hinders controlling their assembly both from thermodynamic and dynamic points of view. The thermodynamic question is what should be the appropriate potential to stabilize microphases, such as cluster crystal, cylindrical, double gyroid and lamellar, while the dynamic question is whether the current experiments are long enough for these phases to appear. This dissertation will focus on solving these two parts of problems and hopefully guide the experiments to discover a simple material that can have microphase segregation behavior. In order to answer the thermodynamic problem of the stability of the microphases, we use a novel thermodynamic integration method as well as density functional methods in comparing the free energy of the microphases with uniform liquids. With the thermodynamic integration, we locate FCC-cluster, cylindrical, double gyroid and lamellar phases as well as nontrivial interplay between cluster, gel and microphase formation for a model microphase former. We also extended the methods to the model with a shorter and longer repulsion region where we found that the shorter region of the system may be in the Wigner glass of clusters of different sizes rather than the microphases. We also compare our simulation results with that from the density functional theory where we demonstrate that the classical density functional theory is qualitatively right but the simple improvement of the radial distribution functional by assuming the system is the same as Percus-Yevick hard sphere does not make a quantitatively difference. Our finding confirms that if the colloidal system has proper SALR potential as well as the right regime of area fraction and temperature, the microphase will be found in these systems. We then answer the second question which is whether the slow dynamics hinders the formation of microphases. We study the modeled microphase former and track the change of the first peak in the structure factor as well as the structural correlation time. We found that the system has a very complex dynamical regimes, including homogeneous fluid, void micelle, liquid gel and solid gel. The system becomes extreme slow in the solid gel regime but if in the regime that density and temperature are near the order-disorder transition, the lamellar self-assembly is much faster than the relaxation time of the solid gel which may explain why in the experimental system, the colloids seem stuck forever. We have collaborated with an experimental group to realize the SALR self-assemble behavior in a well controlled system. We have calibrated the system using a high precision thermodynamic integration by determining and matching the critical point and triple point of the experiments when the system is set up in the purely attractive regime. The system, however, becomes unpredictable when it goes into the SALR system where both higher body and other interactions become dominant. Finally, we try to extend our system to a spherocylinder model, which is an anisotropic particles with SALR. We have developed a novel cell list method here to accelerate the simulation. By determining the percolation transition and the order parameter, we find that the simple anisotropic interaction will introduce a much complex phase behavior of the system even in the disordered regime. We have identified several disordered phases, including homogeneous liquid, micellar liquid, free rotator gel, nematic gel and smectic gel.</p> / Dissertation
107

NORMALIZATION OF THE DELANO DIAGRAM

López-López, F. J. 07 1900 (has links)
QC 351 A7 no. 57 / A normalization of the Delano y,ÿ diagram is proposed in which the y heights are normalized by the entrance pupil height, the heights by the image height. The normalization constants are expressed in terms of the system parameters, and it is seen that the reduced distances become normalized by the focal length of the system, the marginal ray reduced angles by the numerical aperture of the system, the chief ray angles by the field aperture, and the powers by the total power of the system. It is also shown that any number of refractions and transfers will not affect this normalization, but a stop or conjugate shift will destroy it and renormalization then becomes necessary.
108

Matematická teorie žonglování / The mathematical theory of juggling

Zamboj, Michal January 2014 (has links)
Title: The mathematical theory of juggling Author: Bc. Michal Zamboj Department: Department of Mathematics Education Supervisor: RNDr. Antonín Slavík, Ph.D. Abstract: This diploma thesis extends the bachelor thesis of the same name. It deals with the graphic representation of juggling sequences by the cyclic diagram. Using the Burnside theorem and cyclic diagrams, we calculate the number of all genera- tors of juggling sequences. The relation between juggling and the theory of braids is described as well. The mathematical model of inside and outside throws is made from an empirical observation of trajectories of balls. Braids of juggling sequences and their attributes are provided using a real model of ladder. A sketch of the proof of the theorem that any braid is juggleable is given as well.
109

Decision theory to support evacuation in advance of catastrophic disaster including modular influence diagrams and spatial data analysis

Kailiponi, Paul January 2012 (has links)
Catastrophic disaster represents a vital issue in emergency management for many countries in the European Union (EU) and around the world. Given the damage to human lives that different hazards represent, evacuation operations can be the only option available to emergency managers to mitigate the loss of life from catastrophic disaster. However, due to the amount of time needed to effectively evacuate a large area, the decision to evacuate must occur when there is a relatively low probability of the event. An explicit understanding of the evacuation decision can lead to better organisational preparedness in advance of catastrophic disaster events. This research represents work performed with 159 emergency experts and professionals across ten countries. The goal of this research was to create decision-making aids for evacuations in advance of a variety of catastrophic disaster scenarios. Traditional Decision Theory (DT) provides a rational approach to decision-making that emphasizes the optimization of subjective preferences combined with uncertainty. Within evacuation decision-making, DT and its respective outputs are appealing; however the analytical process can be difficult due to the lack of observed data to support quantitative assessments from catastrophic events and relative infrequency of evacuation operations. This research explored the traditional use of DT applied to catastrophic evacuation scenarios. Theoretical contributions to DT and emergency management include: 1) identification of evacuation decision criteria, 2) inter-model analysis between decision structures called Influence Diagrams (IDs), 3) complete application of quantitative decision analysis to support evacuation decision-making and 4) multi-criteria analysis for evacuation vulnerability using spatial data. Important contributions from this work include:1) An analysis of evacuation criteria for a variety of catastrophic disaster scenarios2) Inter-model analysis of evacuation scenarios (flooding, nuclear dispersion and terrorist attack) to identify common probabilistic structures to support multi-hazard strategy planning3) Quantitative decision models to support evacuation strategies, identify key uncertainties and policy analysis 4) Process to use spatial data to support multi-criteria evacuation vulnerability analysis 5) Organisational self-assessment for evacuation decision-making and spatial data use based on findings across all participating countries.
110

Modely pro podporu rozhodování managementu destinace cestovního ruchu / Models Supporting Decision Making of a Tourism Destination Management

STUDENÝ, Zdeněk January 2019 (has links)
This diploma thesis focuses on the application of system thinking and its methods to the issues of decision making within destination management and its organizations. The main aim of the thesis was to create a model to support decision making of destination management organization and to plan sustainable and responsible tourism development in the destination. A partial aim was to create a simplified model in which a simulation of the given system was performed. This aim has been applied to the destination of Cesky Krumlov. The contribution of the work is to find optimal decisions, policies and individual processes in order to assess the subsequent impacts and manage the development of tourism destination towards sustainability.

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