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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

Study of Electro-optical Effects in Polymer Stabilized Blue-Phase Liquid Crystal displays

Liao, Po-Hsuan 26 July 2012 (has links)
In previous studies, I learned the curing of the electro-optical effects in polymer stabilize blue phase liquid crystal under different temperature, such as the hysteresis effect, residual transmittance, drive voltage. So find out before curing blue phase temperature range is very important. Since previous studies have used methods is polarizing microscope and measuring reflectance spectra. In order to the blue phase be used in the display. If we use of Bragg reflectors in the visible blue phase liquid crystal. Resulting in the dark state is not good, the contrast reduction, so we must use the blue phase liquid crystal reflectance spectra in the non-visible light. But this liquid crystal cannot use the previously described methods to define the blue phase liquid crystal temperature range. In our experiment, we use different ways to recognized liquid crystal. We have used polarizing microscope, DSC, Kossel diagram and measuring reflectance spectra. We cannot see blue phase by polarizing microscope and Kossel diagram because the blue phase liquid crystal reflectance spectra in the non-visible light. The liquid crystal material absorbs the UV light. Our DSC resolution is not enough to found the blue phase temperature range. When we recognized liquid crystal, we found the light run through the liquid crystal box. In different phase have different lateral scattering intensity. When we cooling temperature can found the lateral scattering intensity is weak in isotropic. When we phase enter the blue phase II, the lateral scattering intensity rise slowly. When the blue phase II into the blue phase I, we can see first decreased and then increased curve. Last when into the cholesterol phase, the lateral scattering intensity rises quickly. We observe this property can discriminate the blue phase temperature range. When we found the blue phase temperature range, we analyze the hysteresis and drive voltage in different curing temperature. We found this material property. When we curing in high temperature. The drive voltage has decrease, but the hysteresis has increase. When curing in low temperature. The drive voltage has increase, but the hysteresis has decrease. Last we use SEM analyze the polymer structure. But we lost the slight polymer structure when we wash the liquid crystal. So we cannot analyze the slight polymer structure.
42

Design of Transmission Systems for the Manpower-drive Vehicles

Hong, Jhou-nan 27 August 2004 (has links)
¡@¡@The transmission system of manpower-drive vehicles always plays an important role in promotion of riding performance and enjoyment. The purpose of this research is to develop a systematic methodology for the design of the transmission system of the manpower-drive vehicles. First, analyzing the patents of manpower-drive vehicles. Drawing the function structure of the transmission and concluding the basic characteristic. Second, getting several innovative ideas of transmission systems by systematic methodology and comparing with products in patents. Third, according to the requirement charts to design steering systems and frames. Fourth, all design concept variant can be created by using morphological chart method. Several design concepts can be created for new manpower-drive vehicles. Finally, using computer software to assist drawing the models and manufacturing the models. And to establish a simple systematic procedure.
43

The Simulation and Design of Scratch Drive Actuator for Micro Motor Application

Chen, Kuan-ming 28 July 2006 (has links)
This thesis presents the design of a scratch drive actuator (SDA) for Micro Motor Application. In accordance with the force needed to drive the mechanism, the relationship among SDA output force, geometries, and applied voltage is first constructed by employing the principle of virtual work. Having selected the topology of the device, the equations governing the motions and the forces of the micro motor and the actuator can be derived. The SDA and the associated micro motor mechanism are designed by considering the characteristics of Multi-User MEMS Processes, or MUMPs fabrication process. There are several types of SDA used for step motor application being designed and fabricated as illustrative samples. The chip well defined in MUMPs is released by immersing the chip in a bath of HF. It is followed by cleaning in DI water and IPA on a hot plate at 150¢J to reduce stiction.¡@The samples are inspected by OM and SEM, respectively.¡@The experimental and analytical results indicate the practicability of the proposed design concept.
44

The Study of Electro-optical Properties of Passive-drive Vertical Alignment LC Cell

Lee, Hsi-kun 25 January 2008 (has links)
This study investigated the electro-optic characteristics of VAN ¡]vertical-alignment nematic¡^liquid crystal device in passive mode, and tried to present the advantage of high contrast ratio which belongs to VA mode. The experiment consisted of three parts: 1. Change different cell thickness¡]d = 12£gm¡B6£gm¡B4.9£gm¡^. 2. Chang LC with the different value of dielectric¡]£G£`= -3.7¡B-6.1¡^. 3. Chang LC with different refraction anisotropy¡]£Gn = 0.15¡B0.078¡^. We drive those samples with different number of duty in passive mode, and to measure the electro-optic characteristics, including VT curve, response time, and contrast ratio. We knew that STN¡]Super Twist Nematic LCD¡^has the drawbacks of lower contrast ratio, higher operational voltage and slower response time within higher duty in passive mode. And the same problem comes with VAN in passive-drive mode, although it is said VAN has the high performance of contrast ratio. The contrast ratio is worse then STN when driving in higher duty. As a result of VAN is kind of ECB mode, its transparency has a big matter with light retardation. We find that in the same condition of driving duty, the value of cell gap or the £Gn become larger, the value of the sharpness and the contrast ratio become larger.
45

History and architecture of drive-in restaurants in America with a Muncie, Indiana case study

Brosz, Jennifer R. January 2006 (has links)
This thesis contains the results of a study of the architecture and history of drive-in restaurants from their genesis in the late 1920s to their decline in popularity during the 1960s. The study provides a context within which the historic, cultural and architectural significance of this building type can be evaluated. A Muncie, Indiana case study follows the study of the national context. Conclusions are reached concerning how the designs of drive-in restaurants in the Muncie study area compare to national design trends. It provides a framework for further research of the building type.Of the major drive-in restaurant styles, types or forms that were typical on the national scene, the Muncie study area demonstrated only the roadside stand-type, Modern style, and rectangular form. Independent of style or type, Muncie drive-ins demonstrated various interpretations of elements that were common nationally: the sheltering canopy, the pylon, lighting, electronic speaker systems for ordering, and plate glass. It is possible, though, that the Muncie study area contained other restaurants that exhibited national design trends but were demolished and left no record. / Department of Architecture
46

Design and control of a synchronous reluctance machine drive

Sharaf-Eldin, Thanaa January 1999 (has links)
No description available.
47

Simulation and implementation of rotor flux control for an induction motor

Novinschi, Anca January 1998 (has links)
No description available.
48

Transverse flux machines for high torque applications

Maddison, Christopher Paul January 1999 (has links)
Transverse Flux Machines (TFM) present some interesting problems to the machine designer, electro-magnetically and mechanically. They offer the lure of an extremely high specific output, but only, apparently, at the price of intricate three dimensional flux paths, a complicated construction and a low power factor. The research covered by this thesis was concerned with the study, development and improvement of these machines with a view to reducing the detracting aspects of the marque whilst accentuating its advantages. Extensive three dimensional finite element analysis into a wide range of TFM topologies, was coupled with practical investigations into three prototype TFMs constructed at Newcastle University. The result of this work was an improved TFM topology with comparatively good power factor, a simple single sided geometry and a very high specific output.
49

The driving force a comparative analysis of gang-motivated, firearm-related homicides /

Polczynski, Christa G. January 2009 (has links)
Thesis (Ph.D.)--University of Central Florida, 2009. / Adviser: Lin Huff-Corzine. Includes bibliographical references (p. 194-201).
50

A teoria das pulsões em Freud e Lacan: pontos de convergência e de divergência / The theory of Drives in Freud and Lacan: points of convergence and divergence

SILVA NETO, Isaac Vilanova e January 2009 (has links)
NETO, Isaac Vilanova e Silva. A teoria das pulsões em Freud e Lacan: pontos de convergência e de divergência. 2009. 81f. Dissertação (Mestrado em Psicologia) – Universidade Federal do Ceará, Departamento de Psicologia, Programa de Pós-Graduação em Psicologia, Fortaleza-CE, 2009. / Submitted by moises gomes (celtinha_malvado@hotmail.com) on 2012-01-17T14:39:51Z No. of bitstreams: 1 2009_dis_IVESNeto.PDF: 519427 bytes, checksum: 56ce0ee33440e2a9b252f1a8c5173fe9 (MD5) / Approved for entry into archive by Maria Josineide Góis(josineide@ufc.br) on 2012-03-08T16:26:32Z (GMT) No. of bitstreams: 1 2009_dis_IVESNeto.PDF: 519427 bytes, checksum: 56ce0ee33440e2a9b252f1a8c5173fe9 (MD5) / Made available in DSpace on 2012-03-08T16:26:32Z (GMT). No. of bitstreams: 1 2009_dis_IVESNeto.PDF: 519427 bytes, checksum: 56ce0ee33440e2a9b252f1a8c5173fe9 (MD5) Previous issue date: 2009

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