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1	Développement d'une approche multi-échelle de modélisation de dispositifs thermoélectriques : application à des systèmes de capteurs sans fils autonomes sur le corps humain / Development of a multiscale approach for thermoelectric devices modelling : application to wearable wireless autonomous sensors systems Bella, Malika 14 December 2016 (has links) Les dispositifs thermoélectriques, basés sur la conversion d'énergie thermique, offrent des perspectives intéressantes pour le développement de systèmes autonomes. Les principaux défis pour le développement de telles technologies reposent sur l'obtention de dispositifs flexibles, écologiquement et économiquement viables pouvant alimenter des appareils électroniques à faible consommation d'énergie. Le but de cette thèse a donc été de proposer une méthodologie pour l'analyse globale de dispositifs thermoélectriques pour des applications à température ambiante. Dans un premier temps, une approche multi-échelle pour la modélisation de dispositifs thermoélectriques a été développée. A cet effet, trois niveaux d'abstraction ont été considérés. A l'échelle du système, un modèle compact a été développé afin d'évaluer les performances du dispositif dans son environnement. A l'échelle du dispositif, des prototypes virtuels de TEG ont été évalués par le biais de la simulation numérique. A l'échelle des matériaux, la DFT combinée à une approche semi-classique basée sur l'équation de transport de Boltzmann ont été utilisées afin de calculer les propriétés électroniques. La tétraédrite et la famatinite ont été sélectionnées en raison de leurs propriétés prometteuses à température ambiante ainsi que de leur abondance et faible coût. Dans un second temps, des travaux expérimentaux sur la synthèse de nanoparticules de Cu-Sb-S ont été menés. Des nanoparticules quasi-monodisperses avec des tailles inférieures à 50 nm ont été obtenues grâce à la mise au point d'un procédé basé sur la synthèse solvothermale avec surfactant, une méthode faible coût et facilement adaptable à grande échelle. / Thermoelectric devices, capitalizing on waste heat conversion, offer good prospects for the development of autonomous systems. The main challenges for technology development are to obtain flexible, environmentally friendly and low-cost thermoelectric devices with performances sufficient enough to power small electronic devices. The aim of this thesis was thus to propose a methodology for the global analysis of thermoelectric devices for ambient temperature applications. The developed methodology enables the evaluation of key parameters impact on the global system. First, a multiscale approach for thermoelectric devices modelling is developed. In this scope, three parallel levels of modeling are addressed. At the system level, a compact model is developed in order to evaluate overall system efficiency as a function of the thermal environment. At the device level, virtual prototypes of printed devices are built and their performances are evaluated via a finite-element simulation tool. Low temperature gradient has to be dealt with by appropriate architecture design. At the material level, quantum DFT is used in conjunction with semi-classical approach using Boltzmann transport theory to calculate electronic properties. Tetrahedrite and famatinite compounds are chosen due to their promising thermoelectric properties at room temperature and their relative abundance and low cost. Secondly, an experimental work has been conducted on the synthesis of sulphide nanoparticles. Quasi-monodisperse nanoparticles with a size not exceeding 50 nm have successfully been fabricated via a low cost and easily scalable surfactant assisted solvothermal technique. Thermoélectricité Analyse au niveau système Modélisation par éléments-Finis Calculs ab initio Cuivre antimoine soufre Nanoparticules Thermoelectricity System level analysis Finite-Element modelling Ab initio calculations Copper antimony sulphide Nanoparticles
2	Změna kurzu ruské zahraniční politiky v 1. dekádě 21. století / Russia's Foreign Policy Change in the First Decade of the 21st Century Valentová, Emilie January 2010 (has links) The aim of the diploma thesis is to identify Russia's Foreign Policy change in the first decade of the 21st century. It focuses on the three most important strategic documents of the Russian Federation, the presidential decrees signed by Vladimir Putin and Dmitri Medvedev (The Foreign Policy Concepts of the Russian Federation from 2000 and 2008, The National Security Concept of the Russian Federation from 2000, The National Security Strategy of the Russian Federation from 2009 and The Military Doctrines from 2000 and 2010). Through Discourse analysis it concludes that Russia has moved to strenghtening norms of international law and multilateral cooperation between the years 2000 and 2010, it no longer uses confrontational expressions and prefers a multi-vector foreign policy accenting the Asian vector. Russia also proves to be more self-confident and ambitious. We expect a more active role in the world affairs from Russia in the second decade of the 21st century.
3	BEHAVIOR AND DESIGN OF FLOOR TO SPEEDCORE WALL CONNECTIONS UNDER FIRE LOADING Muhannad Riyadh Alasiri (17086912) 10 October 2023 (has links) <p dir="ltr">Composite Plate Shear Wall/ Concrete Filled (C-PSW/CF), also referred to as SpeedCore walls, are being used as innovative shear wall commercial high-rise buildings. These walls offer advantages such as modularity and construction schedule contraction. The cross-section of C- PSWs/CF consists of concrete infill sandwiched between the steel faceplates, where the steel plates are tied together by steel tie bars. Elevated temperatures will result in a deterioration in the mechanical properties of steel and concrete during a fire event in buildings. Such degradation can lead to stability-related failure of structural components. Composite floors are connected to these walls through simple shear connections. The floor-to-wall connections will be exposed to elevated temperatures, which may result in connection failure and progressive collapse of structures.</p><p dir="ltr">Designing SpeedCore walls without fire protection raises concerns regarding the performance of other structural components connected to SpeedCore walls under fire loading including composite floor systems and wall-to-floor connections. Numerical studies conducted on the connections and the floor systems indicated that these structural components undergo thermal compression forces during heating and tensile forces during the cooling phases of a fire event. The goal of this research was to develop an approach for performance-based fire resistance design of complete floor systems consisting of SpeedCore walls, composite floor slabs, and wall-to-floor connections.</p><p dir="ltr">This research includes experimental and numerical analyses to gain insight into the behavior of the floor-to-SpeedCore wall connections under fire and gravity loading. The specimens included steel beams connected to SpeedCore walls through simple shear connections. Three types of floor-to-wall connections were tested including connections with through-plate, reinforcing plate, and unreinforced plate. The parameters considered in the test matrix included: connection type, temperature, loading angle, and loading direction. These parameters in the test matrix were based on results obtained from previous numerical and experimental studies in the literature. The experimental results can fill the existing knowledge gap on floor-to-wall connections for steel-concrete composite members, develop design recommendations, and benchmark numerical models.</p><p dir="ltr">Numerical models were developed to simulate the behavior of the connections (member level) and whole structures (structure level) at ambient and elevated temperatures. Finite Element (FE) analysis and Component-based Models (CB) were utilized to develop the numerical models. The developed models were benchmarked by comparing the obtained numerical results with experimental data reported in the literature. FE models have been validated at two different levels, namely member level, and system level. The performance of the designed connection for the archetype structures was studied using benchmarked FE and CB models. The behavior of various wall-to-floor connections with different steel plate (C-PSW/CF) detailing was investigated.</p><p dir="ltr">Benchmarked numerical models were used to perform a parametric study to evaluate the performance of these connections. UP connection detail was used to perform the study due to its promising experimental performance, which does not need any special detail or plate reinforcement. The study was performed by evaluating the effects of critical parameters on the connection behavior namely, bolt size, target temperature, loading angles, and loading direction</p> Fire safety engineering Structural engineering Fire Structural Engineering SpeedCore wall Component Based Models Connections System Level Analysis Fire Protection C-PSW/CF Thermal Loading Steel Concrete Composite Strucutre Fire loading FE Finite Element Analysis AISC Building code
4	Disruptive Transformations in Health Care: Technological Innovation and the Acute Care General Hospital Lucas, D. Pulane 24 April 2013 (has links) Advances in medical technology have altered the need for certain types of surgery to be performed in traditional inpatient hospital settings. Less invasive surgical procedures allow a growing number of medical treatments to take place on an outpatient basis. Hospitals face growing competition from ambulatory surgery centers (ASCs). The competitive threats posed by ASCs are important, given that inpatient surgery has been the cornerstone of hospital services for over a century. Additional research is needed to understand how surgical volume shifts between and within acute care general hospitals (ACGHs) and ASCs. This study investigates how medical technology within the hospital industry is changing medical services delivery. The main purposes of this study are to (1) test Clayton M. Christensen’s theory of disruptive innovation in health care, and (2) examine the effects of disruptive innovation on appendectomy, cholecystectomy, and bariatric surgery (ACBS) utilization. Disruptive innovation theory contends that advanced technology combined with innovative business models—located outside of traditional product markets or delivery systems—will produce simplified, quality products and services at lower costs with broader accessibility. Consequently, new markets will emerge, and conventional industry leaders will experience a loss of market share to “non-traditional” new entrants into the marketplace. The underlying assumption of this work is that ASCs (innovative business models) have adopted laparoscopy (innovative technology) and their unification has initiated disruptive innovation within the hospital industry. The disruptive effects have spawned shifts in surgical volumes from open to laparoscopic procedures, from inpatient to ambulatory settings, and from hospitals to ASCs. The research hypothesizes that: (1) there will be larger increases in the percentage of laparoscopic ACBS performed than open ACBS procedures; (2) ambulatory ACBS will experience larger percent increases than inpatient ACBS procedures; and (3) ASCs will experience larger percent increases than ACGHs. The study tracks the utilization of open, laparoscopic, inpatient and ambulatory ACBS. The research questions that guide the inquiry are: 1. How has ACBS utilization changed over this time? 2. Do ACGHs and ASCs differ in the utilization of ACBS? 3. How do states differ in the utilization of ACBS? 4. Do study findings support disruptive innovation theory in the hospital industry? The quantitative study employs a panel design using hospital discharge data from 2004 and 2009. The unit of analysis is the facility. The sampling frame is comprised of ACGHs and ASCs in Florida and Wisconsin. The study employs exploratory and confirmatory data analysis. This work finds that disruptive innovation theory is an effective model for assessing the hospital industry. The model provides a useful framework for analyzing the interplay between ACGHs and ASCs. While study findings did not support the stated hypotheses, the impact of government interventions into the competitive marketplace supports the claims of disruptive innovation theory. Regulations that intervened in the hospital industry facilitated interactions between ASCs and ACGHs, reducing the number of ASCs performing ACBS and altering the trajectory of ACBS volume by shifting surgeries from ASCs to ACGHs. Disruptive Disruptive Innovation Theory Disruptive Transformations Disruptive Innovation Innovation Technology Technological Innovation Medical Innovation Medical Technology Medical Advancement Laparoscopy Laparoscopic Surgery open surgery appendectomy cholecystectomy bariatric surgery weight loss surgery appendectomies cholecystectomies inpatient outpatient ambulatory ambulatory surgery ambulatory surgery center acute care general hospital hospital acute care hospital general hospital health care healthcare hospital industry health care industry Clayton Christensen Clayton M Christensen Michael Porter Harvard Business School Virginia Commonwealth University CMS Health policy public policy public administration organizational theory organization theory Population Ecology Theory Competitive Strategy policy analysis John Kimberly Organization Size Structural Inertia liability of smallness health spending health care cost specialty medical facility open system niche width dynamic outpatient department technology shift surgical setting surgical setting shift medical facility shift substitution threat health system system level analysis Ecological Approach hospital trends ambulatory surgery trends reimbursement rate Medicare CMS coverage decision P J DiMaggio DiMaggio and Powell w w Powell Hannan and Freeman M T Hannan Organizational change minimally invasive surgery less invasive surgery Prospective Payment System Outpatient Prospective Payment System entreprenuerial physician health care organization health care management Roice Luke Carl Ameringer new technology surgical utilization elective surgery Medicare Payment Advisory Commission MedPAC coverage decision trends in surgery abdominal surgery surgical variation physician-owned physician ownership physician autonomy outpatient clinic utilization trends unnecessary surgery Pfeffer Salancik technology diffusion redefining health care interdisciplinary research health care delivery panel design diffusion of hospital technology state variation regional variation local health care market government intervention medical facility health care capacity focused factory advances in health care physician organization relationship hospital competition medical specialization hospital expansion medical arms race integrated care integrated health system J E Wennberg health care transformation reimbursement scheme surgical volume Florida Wisconsin policy making health policy analysis competitive dynamics center of excellence intervening factor service line competition service-line competition surgical reimbursement innovative business model innovative technology environmental influence established firm new market entrant patient safety sophisticated technology Harvard Divinity School Social and Behavioral Sciences

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