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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.
41

The Effect of Particle Distribution on the Tracing Rays Diffusion in Diffuser Plates

Tseng, Chun-lung 05 September 2008 (has links)
The liquid crystal display is high light, the advantage thin in thickness. In order to reach the thickness thinly, the request good in degree of consistency, it is important to design a qualified mould group in a poor light. This text introduces how to utilize Trace Pro optics to imitate the software , imitating to the diffusion board of the mould group in a poor light of the liquid crystal display , analysis and designing mainly. To the sidelight type mould group in a poor light, go to type in a poor light mould group construct comparatively simple , main optics for reflect board , spread scene , cold cathode tube and arris lens component its directly. The main use of reflection board lying below the mould group among them , in order to collect and reflect the light that come from the light source, make it penetrate above to in a poor light mould group, in order to increase the luminance of screen. Spread slice and function , arris of lens and the arris lens like mere sidelight type in a poor light mould diffusion slice of group, make their even to take in order to raise the luminance of screen light scattering separately. When the mould group in a poor light is thinner and thinner in thickness, brightness its disparity can more and more heavy too, so optics design more and more challenging. This text designs mainly to spread the distribution that the board adds the particle son to with the high degree of consistency, is it probe into in a poor light mould light neat degree that group can appear to come. Design a series of and reply the mould group which reflect the array, software Trace Pro is enabled being used for designing and replying the geometry structure which reflects the array and shut in the simulation optics route , analog quantity examines the result designed, and discuss its characteristic.
42

The Effects of Filament Preheating and Glow Current on The Life-Cycle of Fluorescent Lamps

Ke, Shih-Pin 10 September 2008 (has links)
This thesis investigates the impact of preheating and glow current on the life-time of rapid-start fluorescent lamps during the starting transient period. A set of electronic ballast circuit is designed to adjust the starting transient preheating current, open-circuit voltage, and preheating time, so that the preheating conditions and the intended amount of glow current can be scheduled. In the experiments, the tested lamps are frequently switched on and off for 35 seconds and 25 seconds, respectively, to accelerate the life-cycle test. Experimental results show that the effect of the glow current on the life-cycle is trivial. Insignificant difference is found between the test lamps with different glow currents when the preheating conditions are the same. On the other hand, the preheating degree is found to be the main factor that affects the lamp life-time. The tested lamps which are adequately preheated last for more than 100000 test cycles. On the other hand, the tested lamps with insufficient preheating are premature with black ends or even damaged only after the several thousands cycles.
43

A Single-Stage High-Power-Factor Constant-Power Electronic Ballast for Metal Halide Lamps

Yang, Chung-sheng 20 July 2009 (has links)
This thesis presents a single-stage high-power-factor electronic ballast for metal halide lamps. The proposed ballast integrates a buck-boost converter, a buck converter and a full-bridge inverter into a single power conversion circuit. The buck-boost converter is designed to be operated at the discontinuous conduction mode (DCM) with a constant duty ratio at a fixed switching frequency to provide a constant lamp power and to achieve a high power factor for a given ac input voltage. The full-bridge inverter supplies a square-wave current for the lamp at a low frequency the same as the line frequency to avoid acoustic resonance. For the universal input voltage ranged from 90 V to 264 V, the lamp remains at the rated power by controlling the duty-ratio of the buck converter. The circuit operation is analyzed in detail to derive the design equations. An electronic ballast for 70 W lamps is designed and tested. Computer simulations and experimental measurements are provided to verify that the proposed ballast has the merits of a nearly unity input power factor, a high efficiency greater than 82 % and can drive the lamp at a constant power.
44

Measuring the level of trust in a mentoring program for leadership development in the local church

Mason, Ralph Peter. January 1900 (has links)
Thesis (D. Min.)--Denver Conservative Baptist Seminary, 1993. / Includes bibliographical references (leaves 298-310).
45

Detekce bakterií rodu Xanthomonas patogenních pro rajče a papriku metodou loop-mediated isothermal amplification

VORÁČKOVÁ, Lucie January 2018 (has links)
The subject of this thesis is the design of specific LAMP primers and LAMP analysis and its optimization. The purpose of this analysis is to specifically distinguish Xanthomonas gardneri from other pathogenic xanthomonads. Two sets of LAMP primers from the DNA sequences of hrpB and atpD genes were designed. These LAMP primer sets are highly sensitive and the detection limit of LAMP assay was found to be 0.01 l / mg of DNA. The reaction temperature of the LAMP was optimized to 64 °C to reach the maximum of amplification. LAMP can be applied to detection and identification on pathogens in plant tissues. LAMP takes less time than conventional PCR to detect bacteria. This LAMP assay has a great potintial to be applied to detection and identification of Xanthomonas genus bacteria pathogenic for tomato and pepper.
46

Nivåer av det lysosomala systemets proteiner i hjärnvävnad från Alzheimerpatienter / Levels of the lysosomal network proteins in brain tissue from Alzheimer's disease patients

Westergren, Samuel January 2014 (has links)
Alzheimers sjukdom är den vanligaste orsaken till demens och i samband med att befolkningen blir större och allt äldre ökar även antalet patienter. Vid sjukdomen sker en hjärnatrofi och de mikroskopiska fynd man ser är extracellulära plack av β-amyloid, intracellulära neurofibriller av fosforylerat tau och förlust av nervcellsutskott, axoner, synapser och dendriter. Några av de tidiga patologiska förändringarna man kan se är störningar i nervcellernas lysosomala system som fyller en viktig roll vid nedbrytning av makromolekyler. I en tidigare studie har man påvisat förhöjda nivåer av proteiner från det lysosomala systemet i cerebrospinalvätska. Syftet med den här studien var att mäta nivåer av det lysosomala systemets proteiner i human hjärnvävnad från patienter med Alzheimer och jämföra dessa med kontrollprover. De sex proteiner som analyserades med Western blot var EEA1, PICALM, LAMP-1, LAMP-2, LC3 och TFEB. Resultaten visar på signifikant ökning i temporala cortex av LAMP-1 och LAMP-2 och en signifikant minskning av LC3 och EEA1 hos patienter med Alzheimers sjukdom. För att kunna dra riktiga slutsatser kring hur de ökade nivåerna i cerebrospinalvätska speglar de olika sjukdomsmekanismerna i hjärnan krävs vidare analyser av fler patientprover samt prover från andra områden i hjärnan. / Alzheimer's disease is the most common cause of dementia, and when the population becomes larger and older also the number of patients increase. A cerebral atrophy and microscopic findings of extracellular plaques of β-amyloid, intracellular neurofibrillary of phosphorylated tau and loss of nerve cell protrusions, axons, synapses and dendrites are seen during the disease. One of the early pathological changes is the disruption of the neuronal lysosomal network that plays an important role in the degradation of macromolecules. In a previous study elevated levels of proteins of the lysosomal network in cerebrospinal fluid from Alzheimer’s disease patients was demonstrated. The purpose of this study was to measure levels of the lysosomal network system in the brain. The six proteins EEA1, PICALM, LAMP-1, LAMP -2, LC3 and TFEB were analyzed in human brain tissue from five Alzheimer's disease cases and five control cases by Western blot. The results show a significant increase in the temporal cortex of LAMP-1 and LAMP -2 and a significant decrease of LC3 and EEA1 in patients with Alzheimer's disease. In order to draw proper conclusions about how the increased levels in cerebrospinal fluid reflect the different disease mechanisms in the brain it requires further analysis of more patient samples and from other areas of the brain.
47

Aid and Empowerment of Local Communities : a qualitative study of the Village Legal Workers Training in the Babati District

Lind Karlberg, Jamilla January 2008 (has links)
In 2003 the Swedish Land Management Program (LAMP) initiated the Village Legal Workers (VLW) Training in the Babati District aiming at empowering local communities through raising awareness of legal rights among the villagers. A VLW is trained in legal rights and will then share his/her knowledge with other villagers through meetings and seminars. The aim of this thesis is to examine the effectiveness of Swedish aid on empowerment of local communities and empowerment of women. To meet these aims of the paper three questions were formulated: to what extent have the goals (empowering local communities) of LAMPs VLWs Training been achieved in Dareda Kati and Haysam, to what extent has the project used a Bottom-up approach and has LAMPs VLWs Training contributed to empowerment of women? To answer these questions a qualitative method was used through semistructured interviews with VLWs and participants of the education by VLWs. Bottom-up approach has been chosen to describe the methods for achieving empowerment and Gender theory has been chosen to describe the procedure of empowerment of women, which consider the social constructions of men and women. The results of this study indicate that VLWs and participants of the education thought that raising awareness of legal rights is of great importance. The expectations and the goals of the project have not quite been fulfilled due to lack of financial resources and support from the Babati District Council (BDC) and the Legal and Human Rights Centre (LHRC).
48

Srovnání klasických žárovek a současných světelných zdrojů z hlediska vzájemných náhrad / Comparison of conventional light bulbs and contemporary light sources in terms of mutual exchange

Kočí, Martin January 2012 (has links)
Term project on comparison of conventional light bulbs and light sources present in terms of mutual compensation marks dissertation, which will pay the same issue. The main pillar of the thesis will be a practical measure, whose structure is indicated below. Semester project constitutes a theoretical basis for a thesis and provides an overall introduction to the issue of compensation light sources. Emphasis is placed on the differences between the light source and the real problems may be encountered by consumers during the transition to another type of light bulbs, respectively. fluorescent lamps. Because consumers often replace the original lamps with compact fluorescent lamps, semester project pays attention to just the differences between ordinary incandescent and energy-saving fluorescent lamps.
49

Porovnání výsledků experimentálních měření dohlednosti s dostupným software / Comparison of Results of Experimental Visibility Measurements with Available Software

Ondris, Róbert January 2012 (has links)
Master's thesis evaluates determined values of visibility from the motor vehicle on the pedestrian by reduced visibility distance when using halogen headlights, which are the results of experimental measurements a compare them with theoretical values determined by assistance of available software.
50

DESIGN OF A CONTROLLER TO CONTROL LIGHT LEVEL IN A COMMERCIAL OFFICE

JAVIDBAKHT, SAEID 03 December 2007 (has links)
No description available.

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