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Hawley, Joshua Christiaan. "Modeling and Simulation of a Cascaded Three-Level Converter-Based SSSC." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/10109.
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This thesis is dedicated to a comprehensive study of static series synchronous compensator (SSSC) systems utilizing cascaded-multilevel converters (CMCs). Among flexible AC transmission system (FACTS) controllers, the SSSC has shown feasibility in terms of cost-effectiveness in a wide range of problem-solving abilities from transmission to distribution levels. Referring to the literature reviews, the CMC with separated DC capacitors is clearly the most feasible topology for use as a power converter in the SSSC applications. The control for the CMC-Based SSSC is complicated. The design of the complicated control strategy was begun with well-defined system transfer functions. The stability of the system was achieved by trial and error processes, which were time-consuming and ineffective.
The goal of this thesis is to achieve a reliable controller design for the CMC-based SSSC. Major contributions are addressed as follows: 1) accurate models of the CMC for reactive power compensations in both ABC and DQ0 coordinates, and 2) an effective decoupling power control technique.
To simplify the control system design, well-defined models of the CMC-Based SSSC in both ABC and DQ0 coordinates are proposed. The proposed models are for the CMC-Based SSSC focus on only three voltage levels but can be expanded for any number of voltage levels. The key system transfer functions are derived and used in the controller design process. To achieve independent power control capability, the control technique, called the decoupling power control used in the design for the CMC-Based STATCOM is applied. This control technique allows both the real and reactive power components to be independently controlled.
With the combination of the decoupling power control and the cascaded PWM, a CMC with any number of voltage levels can be simply modeled as a three-level cascaded converter, which is the simplest topology to deal with. This thesis focuses on the detailed design process needed for a CMC-Based SSSC.<br>Master of Science
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AL, Jowder Fawzi A. Rahman. "Embedded SSSC in series capacitor compensation and in voltage source converter station." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84869.
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This thesis shows that series capacitive compensation of transmission lines by a combination of Static Synchronous Series Compensator (SSSC) and dielectric capacitors lowers the cost of series compensation. The SSSC has two functions: (1) to provide some series capacitive reactance compensation; (2) to damp out incipient unstable Subsynchronous Resonance (SSR) modes. Digital simulation using HYPERSIM shows that for an overall capacitive depth of compensation of 0.7 pu, the SSSC component is only about 1/3 of the capacitive Mvar. Based on the transient stability limit, the transmissibility of the line is increased by a factor of 2.23 for a depth of compensation of 0.7.<br>A second objective of this thesis is to extend the application of the SSSC concept. This application is found in HVDC, where there is no synchronizing power. In the family of Voltage-Source Converter (VSC) HVDC, it is possible to embed the control of the SSSC in the converter station so that there is enhanced synchronizing power. The effectiveness of the synchronizing power (together with damping power) is demonstrated through digital simulations of a turbine-generator system which is connected to a VSC-HVDC Station.<br>The thesis shows that the SSSC has two modes of operation: (1) the constant reactance mode, in which the SSSC voltage is proportional to the line current, and (2) the constant quadrature voltage mode, in which the SSSC voltage is a constant quadrature voltage independent of the line current. A comparison between the two modes shows that the constant reactance mode provides higher synchronizing power and has a higher transient stability limit.<br>Eigenvalue analysis and digital simulations are the methodologies used.
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Silva, Daniel Salomão. "Controle de compensador série síncrono estático baseado em conversores multiníveis em cascata assimétrica." Universidade Federal de Juiz de Fora (UFJF), 2011. https://repositorio.ufjf.br/jspui/handle/ufjf/4108.
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Previous issue date: 2011-09-01<br>O Compensador Série Síncrono Estático (SSSC – Static Synchronous Series Compensator) é um controlador FACTS (Flexible AC Transmission Systems) proposto na literatura para controlar o fluxo de potência pelas linhas de transmissão a corrente alternada. O SSSC é um compensador de potência reativa baseado em conversores eletrônicos de potência de alta capacidade ligados em série com as linhas de transmissão. Neste trabalho são utilizados conversores fonte de tensão (do inglês, VSC – Voltage Source Converters) multiníveis em cascata assimétrica, ligados ao sistema elétrico sem transformadores. O uso do SSSC aumenta as margens de estabilidade, a controlabilidade e a capacidade de transferência de potência de um sistema elétrico. Como a tensão sintetizada pelo SSSC está em quadratura com a corrente pela linha, pode-se utilizá-lo para emular uma reatância série, impor uma tensão ou injetar/absorver potência reativa em série com a linha de transmissão compensada. Neste trabalho são estudados cinco diferentes algoritmos para controlar as tensões geradas pelo SSSC. Resultados de simulações digitais são utilizados para verificar o desempenho de cada algoritmo implementado.<br>The Static Synchronous Series Compensator (SSSC) is a FACTS (Flexible AC Transmission Systems) controller proposed in the literature to control the power flow through the transmission power lines. The SSSC is a series connected compensator based on static power electronics converters. In this work, three single-phase asymmetrical cascaded multilevel voltage source converters (VSC) are used, connected to the electric power system without transformers. The use of SSSC increases the stability limit, the controllability and the transfer power capacity of electric power systems. Since the voltage synthesized by SSSC is in quadrature with line current, it can be used to emulate a series reactance, to synthesize a voltage or to inject/absorb reactive power in series with the compensated transmission line. Five different control algorithms are investigated to control the output voltages of the SSSC. Digital simulation results are used to demonstrate the effectiveness of each control strategy.
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Sadeghzadeh, Nokhodberiz Seyed Mohammad. "Amélioration de la stabilité transitoire des oscillations d'un réseau électrique à l'aide de SMES et de SSSC." Grenoble INPG, 1998. http://www.theses.fr/1998INPG0033.
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Dans ce travail, la stabilité transitoire et l'amortissement des oscillations dans les réseaux électriques sont améliorés en utilisant la commande en ligne du SMES (Superconducting Magnetic Energy Storage) et du SSSC (Static Synchronous Series Compensator). Les commandes proposées sont basées sur la théorie de la logique floue. Dans le cas du SSSC, elle est associée à la fonction d'énergie transitoire. Nous avons également associé une loi de type mode glissant pour éliminer le lien hors ligne entre la commande du SMES et le centre de contrôle des réseaux. Ceci permet un maintien du fonctionnement du régulateur en l'absence de phase d'apprentissage. Le SMES et le SSSC sont connectés à un point intermédiaire d'une longue ligne qui relie deux parties du réseau. Une réalisation pratique du régulateur à été étudié et les mesures nécessaires pour la commande peuvent s'obtenir à partir du noeud auquel est connecté le régulateur. Afin de valider les commandes proposées, elles ont été implantées en simulation sur deux exemples de réseaux : un réseau comportant une ligne et le réseau de New England. Les résultats obtenus montrent une amélioration considérable du temps critique d'élimination du défaut ainsi que l'amortissement des oscillations après le défaut. Notre méthode a également apporté une augmentation de la capacité de transfert correspondant aux lignes de transmission
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Menezes, Maxwell Martins de [UNESP]. "Ajuste de parâmetros de controladores suplementares (POD) através de redes neurais artificiais em dispositivos FACTS TCSC e SSSC." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87112.
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menezes_mm_me_ilha.pdf: 769292 bytes, checksum: 4b80be15a6104228fa9612312498644f (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Este trabalho apresenta estudos referentes à estabilidade a pequenas perturbações do SEP, considerando a atuação de FACTS para o amortecimento das oscilações eletromecânicas de baixa frequência. São abordados os dispositivos FACTS TCSC (Thyristor Controlled Series Capacitor) e o SSSC (Static Synchronous Series Compensator). É realizada a representação e modelagem dos dispositivos FACTS no SEP inserindo no Modelo Sensibilidade de Potência. Para melhorar o desempenho do SEP no que se refere à estabilidade a pequenas perturbações, controladores suplementares são propostos para aumentar o desempenho dos dispositivos TCSC e SSSC, introduzindo o amortecimento necessário ao SEP. Adicionam-se os controladores suplementares POD no modelo modificado para os dispositivos TCSC e SSSC para verificar sua atuação. Para encontrar a melhor localização para instalação dos dispositivos é usado a teoria dos resíduos. Esta mesma teoria é usada também para o ajuste dos parâmetros dos controlares juntamente com outro ajuste feito através de Redes Neurais Artificiais (RNA), que é proposto como alternativa de comparação ao método dos resíduos. Simulações são efetuadas em um sistema teste simétrico para se verificar resultados e a eficácia do controlador POD (parâmetros ajustados pela RNA proposta), acoplados aos dispositivos FACTS, na manutenção da estabilidade a pequenas perturbações do SEP. Palavras-chave: Controladores POD. Estabilidade de sistema de potência. Redes neurais artificiais. TCSC e SSSC<br>This work presents studies referred to short term Electric Power System (EPS) perturbations, considering the actuation of FACTS devices for low frequency electromechanical oscillation damping. The devices considered are: FACTS TCSC (Thyristor Controlled Series Capacitor) and the SSSC (Static Synchronous Series Compensator). It is representation and modeling FACTS devices in the EPS inserting in the Power Sensitivity Model. To improve the performance of the EPS considering the short term perturbations, additional controllers are proposed to increase the performance of the TCSC and SSSC devices, introducing the necessary damping to the EPS. The additional POD controller is added to the modified model for TCSC and SSSC devices to verify the acting. The residual theory is used to find the best location to install the devices. The same theory is used to adjust the parameters of the controllers and an adjustment with Artificial Neural Networks (ANN) is proposed as an alternative to the residual method. Simulations are effectuated for a symmetric test system to verify the efficiency of the POD controller (parameters adjusted by the ANN proposed), coupled with the FACTS devices, to maintain the stability considering the short term perturbations
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Menezes, Maxwell Martins de. "Ajuste de parâmetros de controladores suplementares (POD) através de redes neurais artificiais em dispositivos FACTS TCSC e SSSC /." Ilha Solteira : [s.n.], 2010. http://hdl.handle.net/11449/87112.
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Orientador: Percival Bueno de Araujo<br>Banca: Anna Diva Plasencia Lotufo<br>Banca: George Lauro Ribeiro de Brito<br>Resumo: Este trabalho apresenta estudos referentes à estabilidade a pequenas perturbações do SEP, considerando a atuação de FACTS para o amortecimento das oscilações eletromecânicas de baixa frequência. São abordados os dispositivos FACTS TCSC (Thyristor Controlled Series Capacitor) e o SSSC (Static Synchronous Series Compensator). É realizada a representação e modelagem dos dispositivos FACTS no SEP inserindo no Modelo Sensibilidade de Potência. Para melhorar o desempenho do SEP no que se refere à estabilidade a pequenas perturbações, controladores suplementares são propostos para aumentar o desempenho dos dispositivos TCSC e SSSC, introduzindo o amortecimento necessário ao SEP. Adicionam-se os controladores suplementares POD no modelo modificado para os dispositivos TCSC e SSSC para verificar sua atuação. Para encontrar a melhor localização para instalação dos dispositivos é usado a teoria dos resíduos. Esta mesma teoria é usada também para o ajuste dos parâmetros dos controlares juntamente com outro ajuste feito através de Redes Neurais Artificiais (RNA), que é proposto como alternativa de comparação ao método dos resíduos. Simulações são efetuadas em um sistema teste simétrico para se verificar resultados e a eficácia do controlador POD (parâmetros ajustados pela RNA proposta), acoplados aos dispositivos FACTS, na manutenção da estabilidade a pequenas perturbações do SEP. Palavras-chave: Controladores POD. Estabilidade de sistema de potência. Redes neurais artificiais. TCSC e SSSC<br>Abstract: This work presents studies referred to short term Electric Power System (EPS) perturbations, considering the actuation of FACTS devices for low frequency electromechanical oscillation damping. The devices considered are: FACTS TCSC (Thyristor Controlled Series Capacitor) and the SSSC (Static Synchronous Series Compensator). It is representation and modeling FACTS devices in the EPS inserting in the Power Sensitivity Model. To improve the performance of the EPS considering the short term perturbations, additional controllers are proposed to increase the performance of the TCSC and SSSC devices, introducing the necessary damping to the EPS. The additional POD controller is added to the modified model for TCSC and SSSC devices to verify the acting. The residual theory is used to find the best location to install the devices. The same theory is used to adjust the parameters of the controllers and an adjustment with Artificial Neural Networks (ANN) is proposed as an alternative to the residual method. Simulations are effectuated for a symmetric test system to verify the efficiency of the POD controller (parameters adjusted by the ANN proposed), coupled with the FACTS devices, to maintain the stability considering the short term perturbations<br>Mestre
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Pupin, Carlos Eduardo [UNESP]. "Estudo da estabilidade a pequenas perturbações de sistemas elétricos multimáquinas com dispositivos FACTS do tipo SSSC e controladores suplementares (POD e PSS)." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/87113.
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pupin_ce_me_ilha.pdf: 1801957 bytes, checksum: 06dbcbacdd038bf23cf8b0bfc982dbeb (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Este trabalho apresenta estudos referentes à estabilidade a pequenas perturbações do sistema elétrico de potência, considerando a atuação de FACTS para o amortecimento das oscilações eletromecânicas de baixa freqüência. É abordado o dispositivo FACTS SSSC (Static Synchronous Series Compensator). Para este fim o sistema elétrico é modelado, modificando-se o Modelo de Sensibilidade de Potência para se inserir o compensador. Para melhorar a estabilidade do sistema desenvolvido, controladores são propostos para maximizar o desempenho do dispositivo SSSC, e dessa forma introduzir amortecimento ao sistema elétrico. Acrescenta-se ao modelo desenvolvido os Estabilizadores de Sistemas de Potência (ESP ou PSS – Power System Stabilizers) e o Power Oscillation Damping (POD), para atuação conjunta com o SSSC. Utilizando os fatores de participação e teoria de resíduos é possível encontrar a melhor localização para instalação dos dispositivos e realizar o ajuste dos parâmetros dos controladores. Simulações são realizadas para dois sistemas teste; um de quatro e outro de dez geradores. A partir dos resultados obtidos conclui-se pela potencialidade da utilização do SSSC para a melhoria da estabilidade a pequenas perturbações do sistema elétrico de potência.<br>This work presents studies to provide damping to low frequencies oscillations of the electrical power systems by FACTS devices, considering SSSC (Static Synchronous Series Compensator). This is developed and implemented using the Power Sensitivity Model for multimachine systems. Afterwards, the SSSC devices are introduced as well as the controllers. The PSS (Power Systems Stabilizers) and POD (Power Oscillation Damping) controllers has been included using the participation factor and residue number theory to examine their best allocation on the electrical power systems. The study is based on modal analysis and time domain simulations using two test systems: four and ten generators. The simulation results show the capability of this method for small signal stability improvement for the electric power systems.
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Pupin, Carlos Eduardo. "Estudo da estabilidade a pequenas perturbações de sistemas elétricos multimáquinas com dispositivos FACTS do tipo SSSC e controladores suplementares (POD e PSS) /." Ilha Solteira : [s.n.], 2009. http://hdl.handle.net/11449/87113.
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Orientador: Percival Bueno de Araujo<br>Banca: Francisco Villarreal Alvarado<br>Banca: Élcio Precioso de Paiva<br>Resumo: Este trabalho apresenta estudos referentes à estabilidade a pequenas perturbações do sistema elétrico de potência, considerando a atuação de FACTS para o amortecimento das oscilações eletromecânicas de baixa freqüência. É abordado o dispositivo FACTS SSSC (Static Synchronous Series Compensator). Para este fim o sistema elétrico é modelado, modificando-se o Modelo de Sensibilidade de Potência para se inserir o compensador. Para melhorar a estabilidade do sistema desenvolvido, controladores são propostos para maximizar o desempenho do dispositivo SSSC, e dessa forma introduzir amortecimento ao sistema elétrico. Acrescenta-se ao modelo desenvolvido os Estabilizadores de Sistemas de Potência (ESP ou PSS - Power System Stabilizers) e o Power Oscillation Damping (POD), para atuação conjunta com o SSSC. Utilizando os fatores de participação e teoria de resíduos é possível encontrar a melhor localização para instalação dos dispositivos e realizar o ajuste dos parâmetros dos controladores. Simulações são realizadas para dois sistemas teste; um de quatro e outro de dez geradores. A partir dos resultados obtidos conclui-se pela potencialidade da utilização do SSSC para a melhoria da estabilidade a pequenas perturbações do sistema elétrico de potência.<br>Abstract: This work presents studies to provide damping to low frequencies oscillations of the electrical power systems by FACTS devices, considering SSSC (Static Synchronous Series Compensator). This is developed and implemented using the Power Sensitivity Model for multimachine systems. Afterwards, the SSSC devices are introduced as well as the controllers. The PSS (Power Systems Stabilizers) and POD (Power Oscillation Damping) controllers has been included using the participation factor and residue number theory to examine their best allocation on the electrical power systems. The study is based on modal analysis and time domain simulations using two test systems: four and ten generators. The simulation results show the capability of this method for small signal stability improvement for the electric power systems.<br>Mestre
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Pupin, Carlos Eduardo. "Estabilidade de sistemas de potência com dispositivos FACTS SSSC e STATCOM adaptados ao fluxo de potência, com controladores ESP e POD ajustados pela técnica Particle Swarm Optimization /." Ilha Solteira, 2018. http://hdl.handle.net/11449/180444.
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Orientador: Percival Bueno de Araujo<br>Resumo: Neste trabalho é desenvolvido o modelo matemático de sistemas elétricos de potência multimáquinas para avaliar a estabilidade a pequenas perturbações, com a atuação simultânea de diferentes dispositivos FACTS controlando o fluxo de potência. Os FACTS do tipo SSSC e STATCOM são modelados, considerando suas perdas internas, o modelo resultante é acrescentado à resolução do fluxo de potência, considerando que cada dispositivo FACTS controla uma grandeza do sistema. Utilizando da solução do fluxo, das matrizes Ybarra e Jacobiana, e também tensões e potências, estes são empregados ao Modelo de Sensibilidade de Potência, por meio de simulações, é verificada a atuação dos elementos de controle na estabilidade a pequenas perturbações de sistemas multimáquinas. Para acréscimo de amortecimento às oscilações eletromecânicas, são aplicados controladores ESP e POD. A partir da representação de espaço de estados do modelo final, os autovalores resultantes são estudados para avaliar a estabilidade do sistema. Ao final é discutida a atuação individual e conjunta dos dispositivos FACTS na estabilidade, quando aplicados ao controle do fluxo de potência.<br>Abstract: In this work the mathematical model of multi-machine power electric systems is developed to evaluate the stability to small perturbations, with the simultaneous actuation of different FACTS devices controlling the power flow. The FACTS of type SSSC and STATCOM are modeled, considering their internal losses, the resulting model is added to the resolution of the power flow, considering that each FACTS device controls a quantity of the system. By the solution of the power flux, the Ybus and Jacobian matrices, as well as voltages and powers, these are used to the Power Sensitivity Model, by means of simulations, it is verified the performance of the control elements in the stability to small perturbation of multi-machine systems. For addition of damping to electromechanical oscillations, ESP and POD controllers are applied. From the state space representation of the final model, the resulting eigenvalues are studied to evaluate the stability of the system. At the end, the individual and combined performance of the FACTS devices in the stability, when applied to the control of the power flow, is discussed.<br>Doutor
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Petchenko, Rostyslav. "Rozpad SSSR a transformace Ruska." Master's thesis, Vysoká škola ekonomická v Praze, 2007. http://www.nusl.cz/ntk/nusl-2471.
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Diplomová práce zkoumá proces rozpadu Sovětského svazu a vývoj Ruska v období transformace až do roku 2006. Práce zohledňuje jak hospodářský vývoje země, tak i změny v politickém životě, neboť ekonomická transformace je v Rusku mnohem více než v jiných zemích spojena s transformací politickou. Zvláštní pozornost je věnovaná analýze ruské finanční krize v roce 1998.
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Ladjavardi, Marjan. "Improving small signal stability of power systems in the presence of harmonics." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/511.
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This thesis investigates the impact of harmonics as a power quality issue on the dynamic behaviour of the power systems. The effectiveness of the power system stabilizers in distorted conditions is also investigated. This thesis consists of three parts as follows:The first part focuses on the operation of the power system under distorted conditions. The conventional model of a synchronous generator in the dq-frame of reference is modified to include the impact of time and space harmonics. To do this, the synchronous generator is first modelled in the harmonic domain. This model helps in calculating the additional parts of the generator fundamental components due to the harmonics. Then the Park transformation is used for calculating the modified fundamental components of the synchronous generator in dq axes. The modified generator rotor angle due to the presence of harmonics is calculated and the impact of damper windings under the influence of harmonics is investigated. This model is used to study the small-signal stability of a distorted Single Machine Infinite Bus (SMIB) system. The eigenvalue analysis method is employed and the system state space equations are calculated by linearizing the differential equations around the operating point using an analytical method. The simulation results are presented for a distorted SMIB system under the influence of different harmonic levels. The impact of damper windings and also harmonics phase angles are also investigated.In the second part of the thesis, the effectiveness of the power system damping controllers under distorted conditions is studied. This investigation is done based on a distorted SMIB system installed with a Static Synchronous Series Compensator (SSSC). In the first step, the system state space equations are derived. A Power Oscillation Damping (POD) controller with a conventional structure is installed on the SSSC to improve the system dynamic behaviour. A genetic-fuzzy algorithm is proposed for tuning the POD parameters. This method along with the observability matrix is employed to design a POD controller under sinusoidal and distorted conditions. The impact of harmonics on the effectiveness of the POD controller under distorted conditions is investigated.In the last part, the steady state and dynamic operation of an actual distributed generation system under sinusoidal and distorted conditions are studied. A decoupled harmonic power flow program is employed for steady state analysis. The nonlinear loads are modelled as decoupled harmonic current sources and the nonlinear model of synchronous generator in harmonic domain is used to calculate the injected current harmonics. For the system dynamic stability study, the power system toolbox with the modified model of the synchronous generator is used. The system eigenvalues are calculated and the effectiveness of the installed Power System Stabilisers (PSS) is investigated under sinusoidal and distorted conditions. Simulation results show that in order to guarantee the effectiveness of a PSS in distorted conditions, it is necessary to consider the harmonics in tuning its parameters.
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Nykrýn, Lukáš. "Implementation of NIS Backend for SSSD." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2013. http://www.nusl.cz/ntk/nusl-236214.
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Tato práce se v první části zabývá představením technologií a nástrojů pro centrální správu a přihlašování uživatelů v GNU/Linux. Ukazuje využití adresářových služeb v síťové infrastruktuře, konkrétně služby NIS a její porovnání s dnes pravděpodobně nejrozšířenější adresářovou službou LDAP. Dále práce popisuje proces autentizace na klientských stanicích, konkrétně použití PAM a NSS a možné rozšíření celého systému zavedením cache díky démonu SSSD. Druhá část popisuje návrh a implementaci NIS provideru pro SSSD.
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Jalboub, Mohamed K. "Investigation of the application of UPFC controllers for weak bus systems subjected to fault conditions. An investigation of the behaviour of a UPFC controller: the voltage stability and power transfer capability of the network and the effect of the position of unsymmetrical fault conditions." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5699.
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In order to identify the weakest bus in a power system so that the Unified Power Flow Controller could be connected, an investigation of static and dynamic voltage stability is presented. Two stability indices, static and dynamic, have been proposed in the thesis. Multi-Input Multi-Output (MIMO) analysis has been used for the dynamic stability analysis. Results based on the Western System Coordinate Council (WSCC) 3-machine, 9-bus test system and IEEE 14 bus Reliability Test System (RTS) shows that these indices detect with the degree of accuracy the weakest bus, the weakest line and the voltage stability margin in the test system before suffering from voltage collapse.
Recently, Flexible Alternating Current Transmission systems (FACTs) have become significant due to the need to strengthen existing power systems. The UPFC has been identified in literature as the most comprehensive and complex FACTs equipment that has emerged for the control and optimization of power flow in AC transmission systems. Significant research has been done on the UPFC. However, the extent of UPFC capability, connected to the weakest bus in maintaining the power flows under fault conditions, not only in the line where it is installed, but also in adjacent parallel lines, remains to be studied. In the literature, it has normally been assumed the UPFC is disconnected during a fault period. In this investigation it has been shown that fault conditions can affect the UPFC significantly, even if it occurred on far buses of the power system. This forms the main contribution presented in this thesis. The impact of UPFC in minimizing the disturbances in voltages, currents and power flows under fault conditions are investigated. The WSCC 3-machine, 9-bus test system is used to investigate the effect of an unsymmetrical fault type and position on the operation of UPFC controller in accordance to the G59 protection, stability and regulation. Results show that it is necessary to disconnect the UPFC controller from the power system during unsymmetrical fault conditions.<br>Libyan Government
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Cholasta, Jan. "Správa veřejných klíčů SSH v programech FreeIPA a SSSD." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236572.
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SSH je jeden z nejpoužívanějších protokolů pro vzdálený přístup v Internetu. SSH je flexibilní a rozšiřitelný protokol, který se skládá ze tří hlavních součástí: SSH transportního protokolu, který obstarává důvěrnost, integritu a autentizaci serveru, SSH autentizačního protokolu, který obstarává autentizaci uživatelů a SSH spojovacího protokolu, který obstarává multiplexování více kanálů různých typů (interaktivní sezení, přesměrování TCP/IP spojení, atd.) do jednoho spojení. OpenSSH je jedna z nejrozšířenějších implemetací SSH. OpenSSH obsahuje SSH server, SSH klienty, generátor SSH klíčů a autentizační agent, který usnadňuje autentizaci pomocí veřejných klíčů. FreeIPA a SSSD jsou projekty poskytující centrální správu identit pro Linuxové a Unixové systémy. Tyto projekty sice v době psaní této práce přímou podporu SSH neobsahovaly, ale do jisté míry je ve spojení s OpenSSH používat možné bylo.
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Červinková, Magdaléna. "GAZPROM a ruská zahraniční politika k zemím bývalého SSSR." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-4328.
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This thesis deals with the energy policy of the Russian Federation and its role within the Russian foreign policy towards the countries of the former Soviet Union. It focuses in particular on the Russian state gas monopoly Gazprom. The thesis inquires into Gazprom's relation to the Russian foreign policy and examines how and to what extent Russia uses Gazprom as a tool for enforcement of its political interests. It also analyses the implications of the Gazprom's acitivities in the postsoviet countries for the energy security of the European union.
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Pucholt, Vladimír. "Popis a postup založení ICT SSC." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-162836.
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Diploma thesis deals with the topic of shared service center. Aim of this thesis is to charac-terize ICT SSC and propose a formalized procedure for the establishment of ICT SSC in the Czech Republic. To achieve its objective, the thesis is divided into two pats. The first part presents a theoretical framework of shared service centers. Newly acquired knowledge is used in the second part. The second part presents a formalized procedure establishing ICT shared service centers and case study. Case study is based on real project, which was implemented by an international retail group. The author's contribution to this work lies in comprehensive description of the problem and the integration of theory and practice.
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Jalboub, Mohamed. "Investigation of the application of UPFC controllers for weak bus systems subjected to fault conditions : an investigation of the behaviour of a UPFC controller : the voltage stability and power transfer capability of the network and the effect of the position of unsymmetrical fault conditions." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5699.
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In order to identify the weakest bus in a power system so that the Unified Power Flow Controller could be connected, an investigation of static and dynamic voltage stability is presented. Two stability indices, static and dynamic, have been proposed in the thesis. Multi-Input Multi-Output (MIMO) analysis has been used for the dynamic stability analysis. Results based on the Western System Coordinate Council (WSCC) 3-machine, 9-bus test system and IEEE 14 bus Reliability Test System (RTS) shows that these indices detect with the degree of accuracy the weakest bus, the weakest line and the voltage stability margin in the test system before suffering from voltage collapse. Recently, Flexible Alternating Current Transmission systems (FACTs) have become significant due to the need to strengthen existing power systems. The UPFC has been identified in literature as the most comprehensive and complex FACTs equipment that has emerged for the control and optimization of power flow in AC transmission systems. Significant research has been done on the UPFC. However, the extent of UPFC capability, connected to the weakest bus in maintaining the power flows under fault conditions, not only in the line where it is installed, but also in adjacent parallel lines, remains to be studied. In the literature, it has normally been assumed the UPFC is disconnected during a fault period. In this investigation it has been shown that fault conditions can affect the UPFC significantly, even if it occurred on far buses of the power system. This forms the main contribution presented in this thesis. The impact of UPFC in minimizing the disturbances in voltages, currents and power flows under fault conditions are investigated. The WSCC 3-machine, 9-bus test system is used to investigate the effect of an unsymmetrical fault type and position on the operation of UPFC controller in accordance to the G59 protection, stability and regulation. Results show that it is necessary to disconnect the UPFC controller from the power system during unsymmetrical fault conditions.
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Akyay, Ilkay. "Replication of Akers' SSSL Model on Turkish Male Narcotics Arrestees." VCU Scholars Compass, 2007. http://scholarscompass.vcu.edu/etd_retro/63.
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This research examines the substance abuse severity problem of the male narcotics arrestees of Turkey within the framework of Akers' Social Structural and Social Learning (SSSL) model. The SSSL model is tested to understand the impact of social structural factors on drug abuse severity of narcotics offenders, in mediation of social learning process. The research design consists of secondary data analysis and modeling techniques to test the hypotheses pertaining to the SSSL model. The data, consisting of 1,647 male cases, have been obtained from the TUBIM Program. The U.S. ADAM Program year 2003 data including 6,730 cases have also been utilized with the purpose of observing the similarities and/or differences among substance abusers across the nations, as described in Chapter 5. Accordingly, the narcotics criminals of Turkey and the U.S. were compared in terms of demographic status, criminal background, substance abuse behavior and state of substance related treatment. Eventually, it was found that substance abusing populations across these two nations are significantly different. In the second phase of the study, Akers' SSSL model was developed and tested on the male narcotics offenders of Turkey. Structural Equation Modeling (SEM) analysis was used to test the hypotheses of the study. A model for the drug offenders whose last charge is drug related (substance abuse or substance distribution) was developed and the model's robustness was tested on those narcotics offenders who have reported committing property and violent offenses before the last charge. It is found that the impact of the social factors on drug abuse and dependence behavior through social learning constructs is non-significant except for the age variable for the drug related offenders subset. Furthermore, the impact of all social structural factors on the seriousness of substance abuse in the mediation of social learning constructs is insignificant for the property and violent offenders subset. Also, the social learning construct of the property and violent offenders' subset does not significantly influence the seriousness of substance abuse.
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Čápková, Tereza. "Vztahy Kuba - SSSR 1959-1991: charakteristika a definice jednotlivých etap." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-18098.
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Diploma thesis analyses mutual relations between Cuba and Soviet Union between 1959 (victory of the Cuban revolution led by Fidel Castro) and 1991 (the dissolution of Soviet Union). The thesis is divided into five chapters, first of which deals with the historical development of the island. The rest of the chapters describe circumstances leading to establishing, deepening, or worsening mutual relations and explains the causes of such development. Motivation factors leading both countries to cooperation are object of the work. This thesis intends to find out whether geographical location of Cuba was the main reason for Soviet Union to cooperate and support financially the Caribbean island. The role of Marxism-Leninism ideology in mutual relations is also clarified.
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PINABIAUX, NOWAK VERONIQUE, and PATRICE PINABIAUX. "Sclerose systemique sans sclerodermie : ssss ; a propos de 12 observations." Lille 2, 1991. http://www.theses.fr/1991LIL2M037.
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Clemens, Cathleen McGunigle 1957. "Optical identification of a subset of IRAS SSC sources: A test of the reliability of the SSC Catalog." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/291715.
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The Infrared Astronomical Satellite (IRAS) Serendipitous Survey Catalog (SSC) was constructed from pointed observations made by the satellite when it was in Additional Observations (AO), i.e., non-survey, mode. Analysis of the SSC shows that it contains a higher percentage of sources which have been detected only at 60mum than are found in the IRAS Point Source Catalog (PSC). This could reflect the existence of a large population of faint extragalactic (galaxian) objects due to the increased sensitivity of the SSC relative to the PSC, especially in the 60 mum band, or simply be a result of spurious sources in the SSC. Inspection of cirrus contamination over each AO showed that it had little or no effect on the high 60 mum-only source count. An automated optical identification program presented here indicated that 60 mum-only sources were as likely to have optical counterparts as all other sources, and more likely than randomly-placed artificial sources. The SSC sources studied had, on average, one more optical source found nearby than did artificial data: probably the optical counterpart to the IRAS source. These results support the validity of the 60 mum-only sources and the SSC in general.
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Binti, Mohd Najib Norazwana. "Dual mode suspended substrate stripline (SSS) filter." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/20593/.
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Evolution of wireless communication systems towards high flexibility, low cost and high efficiency leads to tremendous activity in the area of microwave filters. In an RF front-end of a cellular radio base station, signals are being transmitted and received simultaneously. In the receive band, there are chances of intermodulation products from the power amplifier being fed to the receiver,thus the transmit filter must have a very high level of signal rejection. Furthermore, the transmit filter must also have low passband insertion loss since it impacts the power transmitted and the overall transmit system efficiency. Recently, filters with dual-mode operation were being investigated due to their ability to produce two degenerate modes using a single physical structure; therefore, the size and cost of the filter can be reduced without compromising any figure-of-merits. A dual mode suspended substrate stripline filter is presented in this thesis. These filters enable achieving low insertion loss, high Q, high selectivity and good spurious response. Initially, a dual mode ring resonator structure is investigated using suspended substrate stripline technology. This technology is used due to its advantages which are comparable to microstrip or any other planar transmission lines. The HFSS three dimensional finite element method (FEM) is used to evaluate the resonant frequency, quality factor and the first harmonics. A second order suspended substrate stripline filter was designed with capacitive coupled input and output feeding method. The input and output feed were positioned 90 degree from each other while a notch was used in this filter to couple two degenerate modes which also control the bandwidth of the filter. A high performance Generalized Chebychev filter was designed to meet the stringent electrical requirement in the RF front-end of a cellular radio base station. With this fourth order filter, four finite frequency transmission zeros were achieved due to phase cancellation between two paths which results in high selectivity filter response. Metal tuning screws were added to improve any practical imperfections. Finally an asymmetrical Generalized Chebychev filter was designed with real frequency transmission zeros positioned on one side of the passband. With this design, the aim of achieving higher selectivity filter response above the passband was demonstrated.
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Pieri, Naira Caroline Godoy. "Espermatogênese xenogênica pós-transplante de células tronco caninas no testículo de camundongos." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-10052016-120531/.
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As células tronco espermatogoniais (SSCs) são caracterizadas pela capacidade de autorrenovação, proliferação e transmissão das informações genéticas. Em caninos a primeira tentativa de xenotransplante não obteve o sucesso da produção de espermatozoides, no entanto, há evidências de que as células testiculares xenogênicas podem ser transplantadas no testículo do animal hospedeiro, e gerar espermatozoides viáveis do doador. Portanto, este estudo tem como objetivo realizar o xenotransplante das células germinativas caninas em camundongos imunosuprimidos, e com isto promover à produção de espermatozoides caninos viáveis, geneticamente modificados. E por meio desta técnica, analisar a eficiência da espermatogênese pós-transplante. Células germinativas testiculares foram caracterizadas, isoladas e cultivadas de cães pré-púberes, por meio de sistemas de cultura de enriquecimento e fatores de crescimento. As células foram transduzidas com um gene repórter GFP e LacZ, e por um vetor lentiviral para indentificar as SSCs nos testículos receptores. As SSCs transduzidas foram transplantadas nos testículos de camundongos (C57BL/6) tratados com Busulfan, após diferentes períodos os animais receptores foram eutanasiados e analisados. Aos 10 dias de cultivo as células germinativas adultas foram positivas para CD49f, CD117, e com 5 dias uma expressão semelhante de GFRA1 e DAZL, demonstrando a presença de SSCs e algumas células em meiose. Transplantamos 105 células e 20-43% das células transplantadas foram identificadas na membrana basal dos túbulos seminíferos do animal receptor. Portanto, o transplante das células germinativas caninas, mostrou que a purificação e o cultivo realizados são possíveis para obter SSCs caninas, as quais colonizaram os túbulos seminíferos dos camundongos imunodeficientes e mantiveram-se vivas na membrana basal por 90 dias após transplante, mesmo que estes animais tenham distância filogenética<br>The spermatogonial stem cells (SSCs) are characterized by the capacity for self-renewal, proliferation and transmission of genetic information. In canines the first attempt to xenotransplantation did not achieve the success of sperm production. However, there is evidence that testicular xenogeneic cells can be transplanted into the testis of the host animal, and generate viable sperm donor. Therefore, this study aims conduct xenotransplantation of the canine germ cells in immunosuppressed mice, and thereby promote the production of viable sperm canines, genetically modified. And by this technique, analyze the efficiency of post-transplant spermatogenesis. Testicular germ cells were identified, isolated and cultured prepuberes dogs through enrichment culture systems and growth factors. Cells were modificated with a reporter gene GFP and LacZ. The SSCs canine was transplanted in mice (C57Bl/6), after different period and then the recipient animals were euthanized and analyzed. After 10 days in culture the germ cells were positive for CD49f, CD117, and 5 days a similar expression of GFRA1 and DAZL was observed, demonstrating the presence of SSCs and some cells in meiosis. 105 cells were transplanted and 20-43% of the transplanted cells were identified in the basement membrane of the seminiferous tubules after 90 days after transplantation. Therefore, the transplantation of canine germ cells showed that the cultivation and purification are performed possible for canine SSCs, it can colonize the seminiferous tubules the mice infertility remained alive in the basement membrane for 90 days after transplanting, even though these animals have phylogenetic distance
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Zhang, Jin. "Immunological modulation of antioxidants in side-stream cigarette smoke (SSCS) exposed mice." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280048.
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Environmental tobacco smoke (ETS) is a complex mixture of chemicals generated during the burning of tobacco products. The principle contributor to ETS is side-stream cigarette smoke (SSCS), the material emitted from the smoldering tobacco product between puffs Our hypothesis is that reactive oxygen species from SSCS are playing an essential role in disease promotion and antioxidant supplementation (a single form of alpha-tocopherol or a mixture of multiple antioxidants) will potentially prevent SSCS associated tissue damage, pulmonary dysfunction. The specific aims of the present study are to determine if: (1) SSCS would induce tissue lipid peroxidation and proinflammatory responses; (2) SSCS would provoke pulmonary and cardiac function changes; (3) SSCS would cause oxidative stress, reduce nutrient concentrations and suppress immune function in murine retrovirus infections; (4) dietary alpha-tocopherol, specifically, can enhance resistance to oxidative damage by SSCS and improve lung function; (5) multiple antioxidant supplementation can modulate proinflammatory cytokine secretion and tissue lipid peroxidation induced by SSCS exposure in old healthy mice. SSCS exposure methodology in a murine model was developed to facilitate these goals. For the first time we established a SSCS model in murine retrovirus infection. Also we conduced a SSCS dose-response model for a cardiac function study. We found that SSCS exposure in mice consistently increased oxidation, depleted tissue vitamin E levels, and promoted inflammatory cytokines production. SSCS exposure at 120-min/day, 5 days/week for 12 weeks decreased heart contractile function and increased vascular resistance. SSCS induced increased oxidative stress, reduced nutrient concentrations and suppressed immune function, which could make mice with murine retrovirus more susceptible to opportunistic infections. Dietary alpha-tocopherol enhanced resistance against SSCS-induced oxidation and improved lung function, primarily through the antioxidant property of alpha-tocopherol and its modulation of local cytokine production. The multiple antioxidant with beta-carotene, bioflavanoids, Coenzyme Q10, d-alpha-tocopherol, L-ascorbic acid, L-carnitine, magnesium, N-acetylcysteine, retinol, selenium and zinc given as a dietary supplementation prevented oxidation and IL-6 production in healthy old mice during SSCS exposure. (Abstract shortened by UMI.)
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Mann, Mario [Verfasser], and Gahr K. H. [Akademischer Betreuer] Zum. "Einfluss von Näpfchentexturen auf die Reibung von Stahl 100Cr6 und SSiC im einsinnigen oder reversierenden, mediengeschmierten Gleitkontakt gegen Saphir oder SSiC-Keramik / Mario Mann. Betreuer: K.-H. Zum Gahr." Karlsruhe : KIT-Bibliothek, 2013. http://d-nb.info/1064721966/34.
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Ritchie, Samuel Esteban. "The impact of SSC on high-latitude HF communications." Thesis, Lancaster University, 2009. http://eprints.lancs.ac.uk/28099/.
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Hamid, Ahmed Basheer [Verfasser], Thomas [Akademischer Betreuer] Liehr, Wim [Akademischer Betreuer] Damen, and Irmgard [Akademischer Betreuer] Verdorfer. "Small supernumerary marker chromosomes (sSMC) : why do they break, where they break and how to distinguish harmful from harmless sSMC? / Ahmed Basheer Hamid. Gutachter: Thomas Liehr ; Wim Damen ; Irmgard Verdorfer." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2015. http://d-nb.info/1072072696/34.
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SAIF, AHMED MAJED AHMED. "Progettazione e implementazione del controllo di SSBC convertitore multilivello per compensatore sincrono statico." Doctoral thesis, Università degli Studi dell'Aquila, 2021. http://hdl.handle.net/11697/167471.
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Modular multilevel cascaded converters (MMCC) prove to be well-suitable for high and medium voltage systems due to their lower cost and high-redundance design. For STATCOM, Single-Star Bridge-Cell (SSBC) topology is well-applied for its satisfactory performance and superior component count. The feasibility of the adoption of SSBC-STATCOMs relies strictly on their performance and cost-effectiveness. Theoretically, harmonics performance improves with increasing the number of levels. However, this has a direct effect on their design and hence on overall complexity and cost. Besides, when the number of levels increases, more switches are required to be parallelly controlled. Therefore, software-based microcontrollers (e.g. DSPs) show limitations in terms of I/O built-in pins as well as performance. Alternatively, field-programmable gate-arrays (FPGAs), with their parallelism capability, are suitable for implementing the control of SSBC-STATCOM which is composed of output voltage control, internal current control, and capacitor voltage balancing. Although PI regulators are commonly used for their simplicity and ease in implementation, STATCOM system is essentially nonlinear, therefore, a nonlinear controller can effectively improve performance and robustness. Hence, this work initially focuses on investigating some key factors in STATCOM design with an emphasis on their impact on the overall cost in low and medium voltage applications. Then, a backstepping nonlinear control based on Lyapunov function design is proposed to regulate the overall capacitor voltage. Besides, detailed control design and implementation of the proposed control using FPGA is discussed. Hardware set-up of 142 V 9-level SSBC-STATCOM was designed to verify the results. The performance of the proposed method under V_{dc} step change and variation of system impedance has been analyzed and results were compared with the traditional PI controller. Besides, under fault operation, the unbalanced real power within the converter phases of SSBC results in more divergence of capacitor voltages and failure of the control system which affects the safety of the devices or leads to serious system collapse. The method of Zero-sequence voltage v_{z} is utilized to balance the capacitor voltage by adding its waveform to the three-phase ac voltages of the SSBC converter. It can redistribute the active powers between the three clusters without drawing a negative sequence current. Mathematical derivation of the v_{z} using positive and negative sequence is provided and control of STATCOM is simulated with the dual synchronous current control scheme.
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Klímová, Barbora. "Centrum sdílených služeb jako forma sourcingu." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-199259.
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This Master Thesis is focused on the concept of outsourcing and Shared Service Center (SSC) as a tool for reducing operational costs. Outsourcing will be defined along with the various types with advantages and disadvantages of each. Further, the work is focused on process of establishing SSC. The main objective of this thesis is to identify and assess the most important factors for establishing a Shared Services Center. The primary target is divided into the sub- goals. These goals include identifying key factors for locating SSC, assessing the financial benefit of establishing SSC and revelation in which parts of the company savings are highest. Next sub-objective is to evaluate various stages of implementation and progress. The last objective is to evaluate using KPIs as a tool for measuring effectiveness of SSC. For achieving these goals online research, evaluation interviews with executives of Vodafone and internal materials are used. For evaluating of locality are also used methods of managerial decision-making. Theoretical part is followed by a case study. I chose an example of establishing Vodafone SSC in Budapest. On this example my knowledge
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Jeschke, Jonathan M. "Funktionelle Reaktionen von Konsumenten die SSS-Gleichung und ihre Anwendung /." [S.l.] : [s.n.], 2002. http://edoc.ub.uni-muenchen.de/archive/00000515.
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Jeschke, Jonathan Michael. "Funktionelle Reaktionen von Konsumenten: die SSS Gleichung und ihre Anwendung." Diss., lmu, 2002. http://nbn-resolving.de/urn:nbn:de:bvb:19-5159.
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Vavassori, Luca. "SSC: Single-Shot Multiscale Counter. : Counting Generic Objects in Images." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264236.
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Counting object in pictures is a computer vision task that has been explored in the past years, achieving state-of-the-art results thanks to the rise of convolutional neural networks. Most of the work focused on specific and limited domains to predict the number of just one category in the likes of people, cars, cells, and animals. Little effort has been employed to investigate methods to count the instances of different classes at the same time. This thesis work explored the different approaches present in the literature to understand their strenghts and weaknesses and eventually improve the accuracy and reduce the inference time of models aimed to estimate the number of multiple elements. At first, new techniques have been applied on top of the previously proposed algorithms to lower the prediction error. Secondly, the possibility to adapt an object detector to the counting task avoiding the localization prediction has been investigated. As a result, a new model called Single-Shot Multiscale Counter has been proposed, based on the architecture of the Single-Shot Multibox Detector. It achieved a lower prediction error on the ground truth count by 11% (from an mRMSE of 0.42 to 0.35) and an inference time 16x to 20x faster compared to the models found in the literature (from 1.25s to 0.049s).<br>Att räkna objekt i bilder är en datorvisionsuppgift som har utforskats under de senaste åren och uppnått toppmoderna resultat tack vare ökningen av invändiga neurala nätverk. De flesta av arbetena fokuserade på specifika och begränsade domäner för att förutsäga antalet bara en kategori som människor, bilar, celler och djur. Liten ansträngning har använts för att undersöka metoder för att räkna förekomsten av olika klasser samtidigt. Detta avhandlingsarbete utforskade de olika metoder som finns i litteraturen för att förstå deras styrka och svagheter och så småningom förbättra noggrannheten och minska inferingstiden för modeller som syftar till att uppskatta antalet flera element. Först har nya tekniker tillämpats ovanpå de tidigare föreslagna algoritmerna för att sänka förutsägelsefelet. För det andra har möjligheten att anpassa en objektdetektor till räkneuppgiften för att undvika lokaliseringsförutsägelse undersökts. Som ett resultat har en ny modell som heter Single-Shot Multiscale Counter föreslagits, baserad på arkitekturen för Single-Shot Multibox Detector. Den uppnådde ett lägre förutsägelsefel på sanningsräkningen på marken med 11 % (från en mRMSE på 0,42 till 0,35) och en slutningstid 16x till 20x snabbare jämfört med modellerna som finns i litteraturen (från 1,25 till 0,049 sek).
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Káčerová, Martina. "Návrh efektivní personální politiky ve společnosti DSG International SSC,s.r.o." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2009. http://www.nusl.cz/ntk/nusl-222322.
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Tato diplomová práce hodnotí způsob řízení lidských zdrojů ve společnosti DSG International SSC s. r. o. Na základě teoretických východisek se zabývá rozborem jednotlivých personálních činností. Dotazníkové šetření odhaluje silné a slabé stránky týkající se spokojenosti zaměstnanců a charakteristických rysů jejich práce. Navržené kroky na zlepšení poskytují možnost jak v budoucnu dosáhnout větší efektivity v oblasti řízení lidského kapitálu.
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Kulhánek, Stanislav. "Hospodářské reformy v Sovětském svazu (1985 ? 1991)." Master's thesis, Vysoká škola ekonomická v Praze, 2007. http://www.nusl.cz/ntk/nusl-4405.
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Cílem této seminární práce je analýza vývoje charakteristik Sovětského svazu během reformního období spojeného s M. S. Gorbačovem. Právě proměně základních atributů sovětského systému se věnuje první část práce. Pro druhou část práce jsem vybral konkrétní reformní kroky sovětského vedení, které měly přispět k obnovení hospodářského rozvoje. U těchto opatření jsou popsána jejich východiska, zamýšlené důsledky a skutečné dopady. Celá práce by tak měla svým obsahem přispět k diskuzi o možnosti reformování sovětského hospodářství i samotného Sovětského svazu. Práce dokazuje, že upuštění od základních znaků sovětského systému spolu se změnami v hospodářství nevedlo k nastolení rozkvětu ekonomiky a státu. Ale naopak výrazně přispělo k celkové destabilizaci, a proto práce dokazuje nereformovatelnost Sovětského svazu i jeho hospodářství.
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Garin, Etienne. "Développement du 188Re-SSS lipiodol pour le traitement des carcinomes hépatocellulaires." Rennes 1, 2004. http://www.theses.fr/2004REN1B084.
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Nous décrivons une moriginale, simple et reproductible de marquage du lipiodol au technétium 99m et au rhénium 188 pour la radiothérapie métabolique des carcinomes hépatocellulaires. La procédure de marquage repose sur la synthèse d'un complexe lipophile du technétium 99m ou du rhénium 188 (le complexe métal-SSS) secondairement solubilisé dans du lipiodol. Le 99mTc-SSS lipiodol obtenu avec une PCR et un rendement de marquage élevés (respectivement 92 et 96%). Stable in vitro au moins 24 heures. Ns avons vérifié chez le porc sain, que le 99mTc-SSS lipiodol était stable et qu'il se fixait de façon très sélective au niveau du foie, après injection au niveau de l'artère hépatique. Le 188Re-SSS lipiodol obtenu à basse activité avec une PCR et un rendement élevés (respectivement 94 et 97%). Stable in vitro au moins 48 heures. Ns avons vérifié, après injection au niveau de l'artère hépatique chez le porc sain et le rat porteur d'un CHC, que le 188Re-SSS lipiodol se fixait préférentiellement au niveau du foie et se concentrait dans la tumeur avec un rapport de fixation "tumeur/foie non tumoral" voisin de 4. Nous avons mis en évidence une élimination urinaire et digestive très faible du 188Re-SSS lipiodol à l'inverse de ce qui a été décrit antérieurement avec d'autres marquages du lipiodol à l'iode 131 et au rhénium 188. Ce point témoigne d'une meilleure stabilité in vitro du 188Re-SSS lipiodol. Une étude de survie avec l'utilisation d'un mélange 188Re-SSS lipiodol/131i-lipiodol, de 188Re-SSS lipiodol seul et de 131i-lipiodol seul chez le rat porteur d'un CHC a été réalisée. Avec un recul de 6 mois elle n'a pas permis de mettre en évidence de supériorité du mélange 188Re-SSS lipiodol/131i-lipiodol ni d'efficacité significative du 188Re-SSSlipiodol. Les résultats de cette étude font évoquer une efficacité limitéé du 188Re-SSS lipiodol sur les lésions de relativement petite taille.
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Johansson, Gustav, and Lukas Kvarfordt. "En analys av förmedlingen och användningen av studentbostäderna i Stockholm." Thesis, KTH, Fastigheter och byggande, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172370.
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Lai, Shin-kwan Flora, and 黎倩君. "Conservation consideration in Hong Kong: a case study of sites of special scientific interest (SSSI)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31259704.
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Lai, Shin-kwan Flora. "Conservation consideration in Hong Kong : a case study of sites of special scientific interest (SSSI) /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19906092.
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Begum, Aysha. "Social interaction in autism spectrum presentation : the development of the Social Situation Stories Questionnaire (SSSQ)." Thesis, University of East London, 2015. http://roar.uel.ac.uk/4528/.
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Autism spectrum presentations are considered ‘lifelong developmental disabilities’ affecting the way individuals communicate and relate to others, thus significantly impacting on social interaction resulting in various social disadvantages. To date, the key psychological theory accepted, as an explanation for difficulties observed in autism presentations is the lack of ‘Theory of Mind’ (ToM), which is considered a facet of social cognition required in understanding how to interact socially with others, through the ability to recognise others as alike but also independent. Despite its popularity there are several limitations of this proposed theory. Furthermore many individuals with autism presentations can pass ToM tests at an older age or in adulthood. This has resulted in more sophisticated ToM tests being developed. This study aims to develop a more sensitive ToM test, which aims to operationalise a more subtle aspect of ToM that adults with autism presentations may have difficulty understanding. The concept of social overtures which are often present in normative social interaction is used in the current study to develop items to discriminate between individuals with and without autism presentations in a questionnaire format. This new test called the Social Situation Stories Questionnaire (SSSQ) was administered to 12 adults with autism presentation and 16 adults without this diagnosis in a matched cohort study. The SSSQ is a two part instrument consisting of general ToM skills and more subtle ToM skills (social overture detection). Findings show no difference between the two groups on the general part of the SSSQ, however individuals with autism presentations were less able to detect the social overtures, thus scoring less well on the more stringent ToM component of the SSSQ. This novel social cognition test will be used to further understand social interaction differences between adults with and without autism presentation. Taking a critical realistic epistemological approach differences observed are critically discussed.
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Kashapov, Timur. "Diplomatické vztahy a ekonomická spolupráce Československa a Sovětského Svazu v období 1948-1968." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-4480.
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Tato práce je zaměřena na zkoumání politických a ekonomických souvislostí vztahů Sovětského Svazu a Československa v období po nástupu komunismu v roce 1948 až do 1968, kdy se uskutečnila intervence států Varšavské smlouvy, která ukončila reformní proces v ČSSR. Obsahuje charakteristiku vztahů dvou zemí v období před rokem 1948, které vytvořilo předpoklady pro vzájemnou spolupráci a vycházela z konkrétní politické situace jak ve vnitřní politice, tak i na mezinárodní scéně, a po roce 1968, pro které bylo charakteristické ekonomický úpadek a pokles vzájemného obchodu mezi zeměmi, samotné zkoumané dvacetileté období, které je považováno za nejúspěšnější v dějinách takzvaného Východního bloku a obou zemí, kdy jejich politická a ekonomická váha ve světě dosáhuje vrcholu pro Československou republiku v poválečném období a pro SSSR v dějinách země, a také charakteristiku fungování Rady vzájemné hospodářské pomoci, v jejimž rámci probíhá vzájemný obchod ČSSR a SSSR v tomto období. Úlohou práce je pak zhodnotit pozitivní a negativní stránky vývoje vztahů mezi oběma zeměmi v tomto období z politického a ekonomického hlediska.
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Ndoye, Siny. "Fonctionnement dynamique du centre d'upwelling Sud-Sénégalais : approche par la modélisation réaliste et l'analyse d'observations satellite de température de surface de la mer." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066372/document.
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L’extrémité sud du système du courant des Canaries comprend un centre d’upwelling (résurgence localisée d’eaux froides sous l’action de vents favorables) qui a jusqu’ici reçu peu d’attention. Ma thèse porte sur la dynamique de ce centre d’upwelling sud Sénégal ou SSUC (Southern Senegal Upwelling Center en anglais). Elle s’intéresse donc à la circulation et à la structure thermohaline sur le large plateau sud-sénégalais, entre la côte et _100-200 km au large en se focalisant sur la période d’upwelling (Novembre-Mai). Une des particularités de la zone est la séparation entre la zone d’upwelling au centre du plateau et des eaux plus chaudes au large et à la côte. Mes travaux combinent analyse d’images satellite et d’observations in-situ, avec la réalisation et l’analyse de simulations numériques dans l’état de l’art. Par une analyse fine des conditions physiques de la zone, ils posent la base à une approche intégrée du fonctionnement de l’environnement marin sénégalais. Une première partie des résultats se base sur l’examen et l’analyse de plus de 1500 images satellite de température de surface de la mer SST MODIS, contextualisées par rapport aux conditions synoptiques de vent. Cette analyse met en lumière l’existence d’états récurrents du SSUC, en termes de SST. Elles confirment plus généralement la régularité et la stabilité du fonctionnement dynamique du système, mais aussi révèlent des aspects subtils de la structure de l’upwelling : refroidissement des eaux de surface probablement dû au déferlement et au mélange associé à la marée interne ; interaction complexe entre la remontée locale, le courant de Mauritanie et le jet côtier ; complexité probable des échanges entre les différentes parties du plateau (plateau intérieur accueillant des eaux réchauffées, plateau central où est fréquemment situé la langue d’eau froide). L’amplitude du cycle diurne suggère que de grandes incertitudes restent à lever dans le budget de chaleur de l’upwelling . Les limites des études soulignent la nécessité de continuer la mesure in situ dans le SSUC, en particulier des vents. Le fonctionnement dynamique du SSUC est aussi étudié par la modélisation hydrodynamique (ROMS) à haute résolution (_2km). Différentes simulations ont été réalisées en variant les forçages (climatologiques ou synoptiques pour le vent ; modification fine échelle des flux de chaleur en domaine côtier ; présence ou absence de marée). Les solutions numériques montrent en général un bon accord avec les observations satellite et in situ disponibles. Ces solutions éclairent le fonctionnement dynamique du système notamment en termes de circulation, de position de remontée d’upwelling, mais également du devenir des eaux upwellées grâce à une analyse lagrangienne. Nous avons notamment pu montrer que la zone nord du SSUC est la zone principale de remontée et les eaux qui y remontent, proviennent en grande majorité de la zone sud du SSUC d’où elles sont amenées par le courant de Mauritanie. Les analyses lagrangiennes ont aussi permis de - 3 - révéler la dynamique associée à la zone côtière de nourricerie et de nuancer le schéma conceptuel de rétention précédemment admis. La sensibilité de la dynamique du SSUC aux forçages atmosphériques est modeste avec néanmoins des modulations des échanges cross-shore qui peuvent être importantes pour l’écosystème<br>The southern end of the Canary current system comprises of an original upwelling center that has so far received little attention. This Ph.D. Thesis focuses on the dynamical functioning of the Southern Senegal-Gambia Upwelling Center (SSUC). We are interested in the upwelling circulation and thermohaline structure on the shelf between the coastline and 100-200 km offshore. Our focus is on the upwelling period (November to May). The main originality of the SSUC compared to other upwelling centers stems from its continental shelf that is broad and shallow (20–30 m over tens of kilometers). The normal state of the system comprises the classical upwelling front but also a well-defined inner-shelf front that separates cold upwelled waters from nearshore warmer waters. We investigate its dynamical functioning using analysed satellite images, in situ data and state-of-theart 3D numerical simulations. Through a fine-scale analysis of the physical conditions of the SSUC, this work poses the basis of an integrated approach to the Senegalese marine environment functioning. A first part of results is based on the careful examinations and analysis of over 1500 satellite images of sea surface temperature scenes contextualized with respect to wind conditions. Analysis confirm the regularity and stability of the SSUC dynamical functioning (as manifested by the recurrence and persistence of particular SST patterns). The analysis also reveal subtle aspects of its upwelling structure : shelf break cooling of surface waters consistent with internal tide breaking/mixing ; complex interplay between local upwelling and the Mauritanian current off the Cape Verde headland ; complexity of the inner-shelf/mid shelf frontal transition. The amplitude of the diurnal cycle suggests that large uncertainties exist in the SSUC heat budget. The studies limitations underscore the need for continuous in situ measurement in the SSUC, particularly of winds. The dynamical functioning of SSUC is also investigated by means of numerical simulations, using the hydrodynamical Regional Ocean Modeling System ROMS (_x _ 2 km). Different simulations have been carried with varying forcings (climatological or synoptic wind ; fine-scale adjustments of heat flux in coastal area ; presence or absence of tides). Numerical solutions show a good agreement with available satellite and in situ observations . These solutions clarify the dynamical functioning of the system especially in terms of circulation, location of cold water upwelling but also fate of upwelled water through a Lagrangian analysis. We show in particular that the northern part of the SSUC is the main upwelling area. Waters that upwelled in this area predominantly come from the southern of the SSUC, through advection by the Mauritanian current. Lagrangian analysis also revealed the dynamics associated with the coastal area of nursery and nuance the conceptual retention scheme previously admitted. The sensitivity of the dynamics of SSUC to atmospheric forcings is modest with nevertheless some modulations of the cross-shore exchanges that may be important to the ecosystem
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Maouche, Ahmed. "Caractérisation de voies de régulation paracrine potentiellement impliquées dans le devenir des cellules souches spermatogoniales chez la truite arc-en-ciel (Oncorhynchus mykiss)." Thesis, Rennes, Agrocampus Ouest, 2018. http://www.theses.fr/2018NSARA083.
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Chez les mammifères, les cellules souches germinales primordiales nommées PGC sont soumises à différents microenvironnements successifs au sein de la gonade mâle qui permettent leur transition progressive d’abord en prospermatogonies avant la naissance puis en cellules souches spermatogoniales (SSC) chez l’adulte. Chez les poissons, l’existence potentielle d’états de transition intermédiaires entre les PGC et les SSC reste à être démontrée. De même, les mécanismes moléculaires impliqués dans la construction du pool initial de SSC ou dans son maintien à l’âge adulte restent mal compris. Le premier volet de la thèse a eu pour objectif d’étudier des voies de régulations susceptibles d’être impliquées dans le processus de formation, de renouvèlement ou de recrutement des SSC chez la truite arc-en-ciel (Oncorhynchus mykiss).Le profil d’expression spatiotemporelle des gènes codant pour les ligands Kit, Gdnf, endothéline (Edn) et leurs récepteurs respectifs suggère que ces gènes pourraient agir successivement sur les SSC au cours de l’ontogenèse de la truite. A la différence des mammifères, les facteurs kit et gdnf pourraient agir à la fois de manière paracrine et autocrine. L’hormone folliculo-stimulante et les stéroïdes sexuels pourraient réguler les voies gdnf et edn. Le deuxième volet de la thèse a eu pour objectif d’améliorer la praticabilité de la méthode de transplantation des SSC pour régénérer des ressources génétiques précieuses. Nous montrons que la transplantation de SSC non purifiées dans la cavité abdominale d’embryons de truites « golden » triploïdes permet, chez<br>In mammals, Primordial Germ Cells (PGCs) are subject to sucessive microenvironments that allow their progressive transition first, into prospermatogonia at pre-natal stage and then into spermatogonial stem cells (SSC) in adults. In fish, the potential existence of intermediate transition states between PGC and SSC remains to be demonstrated. Likewise, the molecular mechanisms involved in the construction of the initial SSC pool or in its maintenance in adulthood remain poorly understood. The firUnlike mammals, the extracellular Kit and Gdnf ligands are duplicated and they could act as paracrine or autocrine regulatory factors. The follicle stimulating hormone and sex steroid hormones could regulate the gdnf/gfra1 and edn/ednr regulatory pathways. The second part of the thesis was aimed to improve the practicability of the SSC transplantation technique to regenerate valuable genetic resources in European aquaculture research infrastructures. We show that the transplantation of unpurified SSC into the abdominal cavity of triploid "golden" trout embryos allows, in approximately 70% of the injected animals, a satisfactory production of functional gametes derived solely from transplanted SSC
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Guedes, Sales Daniella. "Etude des mécanismes d'endommagement d'aciers martensitiques associés au SSC (Sulphide Stress Cracking)." Thesis, La Rochelle, 2015. http://www.theses.fr/2015LAROS041.
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Dans le cadre de ces travaux, il a clairement été établi que l’hydrogène piégé ou diffusible pouvait avoir une forte influence sur les propriétés mécaniques des matériaux. Cependant, cet effet varie de façon importante en fonction de leur microstructure, leur composition chimique et leur traitement thermique. En effet, les aciers martensitiques trempés/revenus dédiés à des tubes pour des milieux sous-service présentent, de par leur structure, différents types de pièges tels que les dislocations, les joints de grains, les précipités, les inclusions, les lacunes et d’autres interfaces qui jouent un rôle important dans les mécanismes endommageants. Ces aciers de haute résistance mécanique, lorsqu’ils sont soumis à des contraintes mécaniques et à un environnement agressif (qui dépend de la pression en H2S et du pH de la solution) peuvent rompre à cause du phénomène de Sulphide Stress Cracking (SSC). Ce dernier est une forme de fragilisation par l’hydrogène (FPH) qui inclut un amorçage de fissure suivi d’une étape de propagation conduisant à la rupture, dont la contribution de l’hydrogène reste encore mal comprise. En parallèle de l’impact de la microstructure de l’acier, les champs de contrainte et déformation subis par le matériau modifient les effets induits par l’hydrogène. C’est pourquoi un montage de perméation sous contrainte a été utilisé afin de pouvoir réaliser des essais mécaniques jusqu’à rupture sous flux d’hydrogène et les comparer au comportement du matériau lorsque celui-ci est sollicité à l’air ou dans un environnement H2S. Ainsi, l’impact sur le comportement mécanique du flux d’hydrogène mais également de son piégeage peut être étudié. Dans ce cadre, des éprouvettes plates et axisymétriques, lisses et entaillées ont été employées. Les informations expérimentales obtenues dans ce travail ont servi à alimenter un modèle numérique qui a permis de caractériser localement l’état mécanique et les concentrations d’hydrogène piégé et diffusible dans le matériau. Ceci a rendu possible la définition d’un critère local de rupture<br>The findings of this work established that the diffusible and trapped hydrogen could have a strong influence on the mechanical properties of materials. However, this effect varies significantly with the materials’ microstructure, chemical composition, and heat treatment. Due to their structure, quenched and tempered martensitic steels (developed for tubes suitable for sour service environments) have different types of traps such as dislocations, grain boundaries, precipitates, inclusions, vacancies and other interfaces that play an important role in the damage mechanisms. These high strength steels may break due to Sulphide Stress Cracking (SSC) if subjected to mechanical stress and an aggressive environment (which depends on the H2S partial pressure and pH solution). This phenomenon is a form of hydrogen embrittlement (HE) that includes a crack initiation followed by a propagation step leading to failure. However the hydrogen contribution is still insufficiently understood. In addition to the impact of the microstructure on the steel, the stress and the deformation fields in the material also modify the effects induced by hydrogen. To investigate this event, electrochemical permeation tests under stress were used to perform mechanical tests under hydrogen flux until failure is reached. The results were compared to those mechanically loaded in air or in a H2S environment. This enabled the examination of the impact of the hydrogen flux and trapping on the mechanical behavior of martensitic steel. In this framework, flat and axisymmetric, smooth and notched specimens were employed. Experimental data obtained in this work were used to provide a numerical model that enables the locally characterization of the mechanical condition and the concentrations of trapped and diffusible hydrogen in the material. These outcomes enabled us to determine a local failure criterion
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Flores, Kristin K. "Latino student perceptions of TRiO/SSS program effectiveness at Eastern Illinois University /." View online, 2008. http://repository.eiu.edu/theses/docs/32211131400059.pdf.
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Nohrenius, Peter, and Madeleine Åsander. "Dyka efter spänning : Sensation seeking scale testad på dykare." Thesis, Högskolan Kristianstad, Sektionen för lärande och miljö, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-9461.
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Är dykare spänningssökare? Är män mer spänningssökande än kvinnor? 51 dykare, 27 män och 24 kvinnor, läts fylla i enkäten Sensation seeking scale version 5 (SSS-V). Sensation seeking scale har utvecklats av Marvin Zuckerman med kollegor sedan 1960-talet och mäter graden av spänningssökande personlighetsdrag, på engelska: sensation seeking. Enkäten har visat sig valid på flera hundra studier men har bara testats på dykare ett fåtal gånger. Hypoteserna är att dykare är mer spänningssökande än normalpopulationen (H1) och att dykande män är mer spänningssökande än dykande kvinnor (H2). Kontrollgruppen består av psykologistudenter från Delware University mellan år 1986 och 1992, 410 män och 807 kvinnor. Resultatet visar med statistisk signifikant säkerhet att dykare är mer spänningssökande än normalpopulationen och att dykande män är mer spänningssökande än dykande kvinnor. Validitet och alternativ till Sensation seeking scale m.m. tas upp i diskussionsdelen.
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Veselá, Ilona. "Účetní centra sdílených služeb a jejich zavedení." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-142231.
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This diploma thesis is focused on the area of outsourcing and Shared Services Centers. It includes an introduction to outsourcing, its history, the life cycle and the advantages and disadvantages associated with it. The paper is than focused on the Shared Services Centers model, their definition, description, history and benefits and risks arising from them. The thesis also analyzes problems of the implementation process of accounting shared services from a theoretical point of view. This theoretical part is followed by a case study about an establishment of SSC by Czech companies.
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Esnault, Yann. "Etude du gène SSS1 de saccharomyces cerevisiae et de son produit, un composant essentiel du translocon." Paris 6, 1994. http://www.theses.fr/1994PA066821.
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Feng, Xiaohu. "SIC BASED SOLID STATE POWER CONTROLLER." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_diss/543.
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The latest generation of fighter aircraft utilizes a 270Vdc power system [1]. Such high voltage DC power systems are difficult to protect with conventional circuit breakers because the current does not automatically go to zero twice per cycle during a fault like it does in an AC power system and thus arcing of the contacts is a problem. Solid state power controllers (SSPCs) are the solid state equivalent of a circuit breaker that do not arc and which can respond more rapidly to a fault than a mechanical breaker [2]. Present SSPCs are limited to lower voltages and currents by the available power semiconductors [8,9]. This dissertation presents design and experimental results for a SSPC that utilizes SiC power JFETs for the SSPC power switch to extend SSPC capability to higher voltages and currents in a space that is smaller than what is practically achievable with a Si power switch. The research started with the thermal analysis of the SSPCs power switch, which will guide the development of a SiC JFET multi-chip power module to be fabricated by Solid State Devices Inc. (SSDI) using JFETs from SiCED and/or Semisouth LLC. Multiple multi-chip power modules will be paralleled to make the SSPC switch. Fabricated devices were evaluated thermally both statically and dynamically and electrically both statically and dynamically. In addition to the SiC module research a detailed design of the high voltage SSPC control circuit capable of operating at 200andamp;ordm;C was completed including detailed analysis, modeling and simulations, detailed schematic diagrams and detailed drawings. Finally breadboards of selected control circuits were fabricated and tested to verify simulation results. Methods for testing SiC JFET devices under transient thermal conditions unique to the SSPC application was also developed.
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Curran, Edouard. "Mécanismes cellulaires et moléculaires potentiellement impliqués dans la régulation du stock de cellules souches spermatogoniales chez le poisson-zèbre Danio rerio." Thesis, Rennes, Agrocampus Ouest, 2016. http://www.theses.fr/2016NSARH099/document.
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Les capacités d’auto-renouvellement ou de différenciation progressive en gamètes des cellules souches spermatogoniales (SSC) sont indispensables à la production de spermatozoïdes tout au long de la vie des individus de sexe mâle. Les travaux réalisés au cours de la thèse ont eu pour objectif de mieux comprendre les mécanismes cellulaires et moléculaires potentiellement impliqués dans le contrôle du devenir des SSC chez les poissons téléostéens. Grâce à une nouvelle lignée de poisson-zèbre transgénique exprimant la GFP sous le contrôle d’un nouveau fragment promoteur du gène vasa, nous avons caractérisé une sous-population de spermatogonies indifférenciées composés de doublets asymétriques. L’ensemble de nos observations suggère que ces doublets asymétriques constituent un pool de cellules souches recrutées pouvant soit poursuivre leur différenciation spermatique soit participer à la dynamique de renouvèlement du stock de SSC.Une approche de séquençage à haut débit des transcrits exprimés au sein des spermatogonies indifférenciées fluorescentes et des cellules de Sertoli met en évidence la diversité des voies de régulation paracrine potentiellement impliquées dans le contrôle du devenir des SSC (molécules d’adhésion cellulaire, cytokines, facteurs de croissance…). Les analyses phylogénétiques montrent que certaines de ces voies de régulation sont conservées chez les Gnathostomes alors que d’autres ont été perdues chez les tétrapodes ou les mammifères seulement. Une approche comparée initiée chez la truite arc-en-ciel confirme l’intérêt générique des données acquises chez<br>By their ability to self-renew or differentiate into gametes, the spermatogonial stem cells (SSCs) are essential for sperm production throughout the life of male. The work done during the thesis had for objective the understanding of the cellular and molecular mechanisms potentially involved in the fate of the SSC in the teleost fish. With a new line of transgenic zebrafish expressing GFP under the control of a new gene promoter fragment vasa, we characterized a subpopulation of undifferentiated spermatogonia composed of asymmetric doublet. The observation of the GFP protein indicates that these doublets can fragment to generate isolated spermatogonia. Transplantation of fluorescent spermatogonial cells into the abdominal cavity of a recipient embryo shows that these cells have all functional properties of SSC. All our observations suggest that asymmetric doublet constitute a pool of stem cells with bivalent fate:they can continue their sperm differentiation or participate in the dynamic renewal of SSC pool. A rnaseq based transcritpome analysis of transcripts expressed in undifferentiated spermatogonia fluorescent and Sertoli cells highlights the diversity of paracrine regulatory pathways potentially involved in the control of the SSC (cell adhesion molecules, cytokines, growth factors, primary metabolites). Phylogenetic analyzes show that some of these regulatory pathways are well conserved among all Gnathostomes while others were lost in tetrapods or mammals only. A comparative approach initiated in rainbow trout generic confirms the interest of the data acquired in th
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Mehmood, Tallat, and Farnaz Khodabandeh. "Ranking suppliers by using the Sustainable Supplier Evaluation Criteria (SSEC) and Multi-Criteria Decision Making (MCDM) methods." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-64703.
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Background: Despite the competition for achieving lower costs and higher profits, companies are nowadays becoming increasingly aware of the environmental and social impacts of their operations. This is unveiled by growing numbers of sustainable activities in companies’ reports. Companies’ are also under more pressure from authorities and public to increase their business’s environmental performance, a so-called sustainable management process. Besides the pressure for developing environmental responsible activities, companies still remain with their low cost measures. Hence, they are concerned with the issue of identifying suitable measures to assess their sustainability.Supplier selection, processes by which companies evaluate, select and maintain their suppliers, regarded as one of the major operations affecting companies sustainable performance. While supplier selection was often performed in the past using conventional measures, there is an essential need to develop a framework for sustainable supplier selection in supply chain. By doing this research the company can ensure its operations are in line with environmental and social regulations and requirements. Research questions: - What is the important and applicable sustainable supplier evaluation criteria (SSEC) that could be applied? - What Multi criteria decision making method (MCDM) is suitable for evaluating and ranking the suppliers? - How would Renault group in Iran rank the supplier against the sustainable supplier evaluation criteria (SSEC)? - Which Sustainable supplier evaluation criteria (SSEC) could help the lowest ranked supplier to improve its sustainability performance? Purpose: The purpose of this research is to develop important and applicable sustainable supplier evaluation criteria (SSEC) and find out the multi criteria decision making method (MCDM) for ranking the suppliers. Furthermore, it also suggests to the manger to improve the sustainability performance of lower ranked suppliers. Method: The empirical data and the conclusions made from Renault Group in Iran are based on qualitative case study. This thesis is written from a positivistic perspective with a deductive approach. Conclusions: The main conclusions of this study are as below: - Developing a comprehensive list of attributes including the most important and applicable Sustainable Supplier Evaluation Criteria (SSEC) for evaluating sustainability performance of supplier for Renault Company in Iran. - TOPSIS is evaluated MCDM method to rank the suppliers against SSEC in Renault group in Iran. - The suppliers of the company are ranked and the best and the weakest supplier are determined using the TOPSIS. - The lowest ranked supplier is showed which SSEC could improve its performance by applying a parametric analysis.