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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Congenital amegakaryocytic thrombocytopenia iPS cells exhibit defective MPL-mediated signaling / 先天性無巨核球性血小板減少症患者由来のiPS細胞はMPLを介した細胞内シグナルが欠落している

Hirata, Shinji 26 March 2018 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13159号 / 論医博第2146号 / 新制||医||1029(附属図書館) / (主査)教授 河本 宏, 教授 前川 平, 教授 髙折 晃史 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
22

Statistical tests for long memory and unit root of high frequency financial data

Chang, Yen-Hsiang 24 July 2008 (has links)
In this thesis, we study the unit root tests which includes the ADF, PP and KPSS tests, the long memory tests such as the R/S and GPH tests, and the applications of these methods in high frequency financial data analysis. The software SPLUS was adopted to analyze data and correction of the SPLUS program in unit tests are also proposed. To apply these two test methods in high frequency data, we quoted the library, HFlibrary designed by Yan and Zivot in 2003 for preliminary data analysis and propose a new library HFanalysis, which can be used in correcting high frequency data (excluding N.A. value, sorting transactions and retrieve a certain time of transactions), obtaining equi-distanced time intervals and testing for unit root and long memory properties. In additions, we apply this proposed library to simulate the power of traditional unit root methods such as the ADF test and long memory test method such as the R/S and to perform an empirical study. Finally, we explore the power of the ADF for testing data simulated from a threshold unit root model and simulate the percentiles of the null distribution of the following threshold unit root tests: WALD, LM, LR and W£f.
23

Energy management and control for hybrid renewable energy sources in rural area / Gestion de l'énergie et de contrôle pour les hybrides sources d'énergie renouvelables en zone rurale

Ahmed, Rana 27 November 2015 (has links)
Cette thèse propose principalement, un algorithme État-Flow MPPT basé P&O, amélioré avec deux degrés de liberté, dans lequel le système événementiel (MPPT) de comportement est modélisé par le décrivant en terme de transition entre les états, sous certaines conditions. Secondairement, un algorithme étendu MPPT, base d'exploitation en parallèle de l'état-débit est en outre proposé d'être une solution difficile pour le contrôle indépendant du système hybride, où la caractéristique de contrôle continu peut se présenter au cours d'un certain état de travail tout en discrète, est indiquée le long des transitions d'état. Deux configurations possibles pour le système hybride sont proposées : deux convertisseurs DC/DC séparés, et un convertisseur de sortie unique à double entrée (DISO) de configurations. Enfin, il est proposé, un comportement du système DC modélisation utilisant État-Flow, menant à l'ensemble de la conception de la stratégie de commande qui concernent RES MPPT, RES et la coordination BESS, la stabilité du système d'alimentation et de régulation de la tension du bus DC. La simulation et les résultats expérimentaux valident l'efficacité et l'applicabilité de l'algorithme proposé. Les deux résultats montrent la supériorité du MPPT basé proposé État-Flow pour réduire les oscillations de puissance RESs à l'état d'équilibre dans diverses conditions d'exploitation, en plus de son démarrage plus rapide, et l’opération de transition sans divergence de la MPP, selon des conditions météorologiques variables. / This thesis primarily proposes, an improved P&O based State-Flow MPPT algorithm featuring two degree of freedom, in which the event driven system (MPPT) behaviour is modelled by describing it in terms of transitions among states under certain conditions. Secondarily, an extended parallel operating State-Flowbased MPPT algorithm is further proposed to be a challenging solution for the independent control of the hybrid system, where continuous control characteristic can present during a certain working state while discrete one is indicated along state transitions. Two possible configurations for the hybrid system are proposed; two separate DC/DC converters and dual input single output converter (DISO) configurations. Finally it is proposed, DC system behaviour modelling using State-Flow leading to the whole control strategy design which concern RESs MPPT, RESs and BESS coordination, power system stability and DC bus voltage regulation.Simulation and experimental results validate the effectiveness and applicability of the proposed algorithm, both results show the superiority of the proposed State-Flow based MPPT in reducing the RESs power oscillations at steady-state in various operating conditions in addition to its faster start-up and transition operation without divergence from the MPP during sudden varying weather conditions.
24

Návrh a realizace mobilní fotovoltaické elektrárny / Design and Realization of Mobile Photovoltaic Power Station

Lednický, Ján January 2017 (has links)
This diploma thesis entitled Design and realization of a mobile photovoltaic power plant is dividet into two parts. In the first, theoretical part one can learn about the state of representation of renewable energy sources in the field of electrical power engineering and about the structure of photovoltaic power station systems. The secont part of this thesis is focused on the own design and realization of the mobile photovoltaic power plant, on the selection of individual suitable components and ther dimensioning. In addition, a model of a mobile power plant has been created, on the basis of which the power plant was constructed. Finally, one can find a source code analysis of a power plant monitoring using a microcontroler
25

Neurotoxins and Neurotoxic Species Implicated in Neurodegeneration

Segura-Aguilar, Juan, Kostrzewa, Richard M. 01 December 2004 (has links)
Neurotoxins, in the general sense, represent novel chemical structures which when administered in vivo or in vitro, are capable of producing neuronal damage or neurodegeneration - with some degree of specificity relating to neuronal phenotype or populations of neurons with specific characteristics (.e., receptor type, ion channel type, astrocyte-dependence, etc.). The broader term 'neurotoxin' includes this categorization but extends the term to include intra- or extracellular mediators involved in the neurodegenerative event, including necrotic and apoptotic factors. Moreover, as it is recognized that astrocytes are essential supportive satellite cells for neurons, and because damage to these cells ultimately affects neuronal function, the term 'neurotoxin' might reasonably be extended to include those chemical species which also adversely affect astrocytes. This review is intended to highlight developments that have occurred in the field of 'neurotoxins' during the past 5 years, including MPTP/MPP+, 6-hydroxydopamine (6-OHDA), meth-amphetamine; salsolinol; leukoaminochrome-o-semi-quinone; rotenone; iron; paraquat; HPP+; veratridine; soman; glutamate; kainate; 3-nitropropionic acid; peroxynitrite anion; and metals (copper, manganese, lead, mercury). Neurotoxins represent tools to help elucidate intra- and extra-cellular processes involved in neuronal necrosis and apoptosis, so that drugs can be developed towards targets that interrupt the processes leading towards neuronal death.
26

Modifying Some Iterative Methods for Solving Quadratic Eigenvalue Problems

Ali, Ali Hasan January 2017 (has links)
No description available.
27

Energy-efficient interfaces for vibration energy harvesting

Du, Sijun January 2018 (has links)
Ultra low power wireless sensors and sensor systems are of increasing interest in a variety of applications ranging from structural health monitoring to industrial process control. Electrochemical batteries have thus far remained the primary energy sources for such systems despite the finite associated lifetimes imposed due to limitations associated with energy density. However, certain applications (such as implantable biomedical electronic devices and tire pressure sensors) require the operation of sensors and sensor systems over significant periods of time, where battery usage may be impractical and add cost due to the requirement for periodic re-charging and/or replacement. In order to address this challenge and extend the operational lifetime of wireless sensors, there has been an emerging research interest on harvesting ambient vibration energy. Vibration energy harvesting is a technology that generates electrical energy from ambient kinetic energy. Despite numerous research publications in this field over the past decade, low power density and variable ambient conditions remain as the key limitations of vibration energy harvesting. In terms of the piezoelectric transducers, the open-circuit voltage is usually low, which limits its power while extracted by a full-bridge rectifier. In terms of the interface circuits, most reported circuits are limited by the power efficiency, suitability to real-world vibration conditions and system volume due to large off-chip components required. The research reported in this thesis is focused on increasing power output of piezoelectric transducers and power extraction efficiency of interface circuits. There are five main chapters describing two new design topologies of piezoelectric transducers and three novel active interface circuits implemented with CMOS technology. In order to improve the power output of a piezoelectric transducer, a series connection configuration scheme is proposed, which splits the electrode of a harvester into multiple equal regions connected in series to inherently increase the open-circuit voltage generated by the harvester. This topology passively increases the rectified power while using a full-bridge rectifier. While most of piezoelectric transducers are designed with piezoelectric layers fully covered by electrodes, this thesis proposes a new electrode design topology, which maximizes the raw AC output power of a piezoelectric harvester by finding an optimal electrode coverage. In order to extract power from a piezoelectric harvester, three active interface circuits are proposed in this thesis. The first one improves the conventional SSHI (synchronized switch harvesting on inductor) by employing a startup circuitry to enable the system to start operating under much lower vibration excitation levels. The second one dynamically configures the connection of the two regions of a piezoelectric transducer to increase the operational range and output power under a variety of excitation levels. The third one is a novel SSH architecture which employs capacitors instead of inductors to perform synchronous voltage flip. This new architecture is named as SSHC (synchronized switch harvesting on capacitors) to distinguish from SSHI rectifiers and indicate its inductorless architecture.
28

Neurotoxins

Kostrzewa, Richard M. 01 January 2016 (has links)
The era of selective neurotoxins arose predominately in the 1960s with the discovery of the norepinephrine (NE) isomer 6-hydroxydopamine (6-OHDA), which selectively destroyed noradrenergic sympathetic nerves in rats. A series of similarly selective neurotoxins were later discovered, having high affinity for the transporter site on nerves and thus being accumulated and able to disrupt vital intraneuronal processes, to lead to cell death. The Trojan Horse botulinum neurotoxins (BoNT) and tetanus toxin bind to glycoproteins on the neuronal plasma membrane, then these stealth neurotoxins are taken inside respective cholinergic or glycinergic nerves, producing months-long functional inactivation but without overtly destroying those nerves. The mitochondrial complex I inhibitor rotenone, while lacking total specificity, still destroys dopaminergic nerves with some selectivity; and importantly, results in the neural accumulation of synuclein-to model Parkinson’s disease (PD) in animals. Other neurotoxins target specific subtypes of glutamate receptors and produce excitotoxicity in nerves with that receptor population. The dopamine D2 receptor agonist quinpirole, termed a selective neurotoxin, produces a behavioral state replicating some of the notable features of schizophrenia, but without overtly destroying nerves. These processes, mechanisms or treatment-outcomes account for the means by which neurotoxins are classified as such, and represent some of the means by which neurotoxins as a group are able to destroy or functionally inactivate nerves; or replicate an altered neurological state. Selective neurotoxins have proven to be important in gaining insight into biochemical processes and mechanisms responsible for survival or demise of a nerve. Selective neurotoxins are useful also for animal modeling of human neural disorders such as PD, Alzheimer disease, attention-deficit hyperactivity disorder (ADHD), Lesch-Nyhan disease, tardive dyskinesia, schizophrenia and others. The importance of neurotoxins in neuroscience will continue to be ever more important as even newer neurotoxins are discovered.
29

Koncept nabíjecí stanice s možností off-grid provozu pro elektrokola / Concept of Charging Stations with off-grid Operation for Electric Bicycles

Leitman, Valentín January 2017 (has links)
This thesis deals with charging stations for electric bicycles powered by renewable energy. The aim of this work is to make a proposal for the hybrid charging stations for electric bicycles, which will work independently and, if necessary, will be backed up by a network. In this thesis is entered theoretical information on the issue of electric bicycles, the batteries, charging stations, the connectors of chargers, and photovoltaic systems. The practical part of this thesis is the basic design of the charging station and its design of the mathematical model of the individual parts in Simulink program, which are linked to the actual design of the charging station. In conclusion, this thesis deals with energy and economic analysis of the proposed system, therein included various methods of assessing investment recommendations of appropriate processing methods and overall assessment of the subject.

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