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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 Characterization of Sn-doped SiO2 Thin Film Resistance Random Access Memory

Liao, Kuo-Hsiao 26 August 2011 (has links)
In this study, The bottom electrode¡]TiN¡^, middle insulator ¡]Sn¡GSiO2¡^, and top electrode ¡]Pt¡^ were deposited respectively by sputtering technique for fabricating the resistive random access memory with metal-insulator-metal structure. Experimental results were indicated that Sn-dopped SiO2 RRAM could be operated over 105 times and retention time was kept stable at thermal stress up to 85 ¢J over 104 s. In the previous researches, we had known that the supercritical carbon dioxide¡]SCCO2¡^ fluids could efficiently to passivate the traps in the devices. The leakage current of dielectric film would be reduced significantly after SCCO2 fluids treatment. To improve the dielectric properties of Sn-dopped SiO2 films, the SCCO2 fluids technology was introduced in this study. After SCCO2 fluids treatment, the leakage current of devices was reduced significantly, because the HRS conduction mechanism was transformed from Poole-Frenkel conduction to Schottky emission and the LRS conduction mechanism was transformed from Ohmic conduction to Hopping conduction. Addtionally, RTA treatment was introduced to improve the Sn-dopped SiO2 films. It could also reduce leakage current of devices after RTA treatment. At last, we used constant current forming to find the process of electrons hopping conduction.
42

The Cluster Strategy Improve The Development of Textile Industry-Silk and Filament District

Feng, Yi-Hsin 20 July 2004 (has links)
Since 1990 Porter has advert the conception that cluster could improve the competitive strength of textile industry, it has arouse highly attention of academe, also a lot of developed countries took this appearance of assemblage policy as the development policy for their industries. The textile industry of Taiwan has been developed around 50 years ago, in nearly years, ascribe to the rise of cost, the value of export continually decrease and the increase of abroad competitors, the textile industry has been considered as a declined industry. However, according to the research it¡¦s still one of the most important industry which can create a lot of foreign exchange; on 2001 Council For Economic Planning And Development has planned to build a silk and filament district in Yunlin particular for the textile industry , for assemble the textile industry and push Taiwanese industries into the textile center of Asia-pacific. According to this research we would like to know how the cluster strategy could improve the development of textile industry in Taiwan. Mainly use Location Quotient analysis to know if the textile industry is the most important basal industry in this area, and with all the related documents we could realist the crux element of the development of cluster strategy, then we could have talk with related industries and companies, in this way we may have a complete view of the whole situation in this industry and the project of having this special area. The combination of above descriptions, we could understand this special area of the textile industry and the production environment, find out the lack part and create a millennium for the development of textile industry. The result of this research discovered that according to the analysis of this industry, the textile industry has highly central tendency and it is the main industry of this area; but according to the crux element of the development, it does not have strong enough connection between local companies and it does not have good enough interactive with schools in this area, it may cause the lack of talent people, knowledge and research. In the future, it is going to be a very important issue that we have to consider about, aggrandize the connection between the local companies and the interactive with schools.
43

Discrete Differential Geometry and Physics of Elastic Curves

McCormick, Andrew Grady 18 October 2013 (has links)
We develop a general computational model for a elastic rod which allows for extension and shear. / Physics
44

On the Role of Linear Processes in the Development and Evolution of Filaments in Air

Roskey, Daniel Eric January 2007 (has links)
It is well known that ultrashort, high intensity pulses with peak powers exceedinga certain critical value (Pcr) undergo self-focusingleading to collapse and filamentation. During the initial stagesof propagation at low intensities the beamdynamics are dominated by diffraction and dispersion. During filamentation, self-focusing resulting from the nonlinear Kerr effect is balanced by higher order nonlinearities such as plasma induced defocusing and absorption.This work examines the role that linear processes combined with initial spatial and temporal conditioningplay in the generation and subsequent evolution of filaments within nonlinearbeams. It is demonstrated that, because of linear diffraction, initial spatial beam shaping can have a dramatic effect on the filament pattern, the number of filaments and the energy contained in each filament. These ideas are applicable to cases that arequite common, such as circularly apodized beams, and help to explain interestingbehavior observed in these types of beams. Finally, it is demonstrated thatwith appropriate preconditioning of multiple subcritical pulses, linear effects can be employed to accurately control when and where filamentation occurs during long distance propagation through conditional collapse of overlapping pulses.
45

Mechanical integrity of myosin thick filaments of airway smooth muscle in vitro: effects of phosphoryation of the regulatory light chain

Ip, Kelvin 11 1900 (has links)
Background and aims: It is known that smooth muscle possesses substantial mechanical plasticity in that it is able to adapt to large changes in length without compromising its ability to generate force. It is believed that structural malleability of the contractile apparatus underlies this plasticity. There is strong evidence suggesting that myosin thick filaments of the muscle are relatively labile and their length in vivo is determined by the equilibrium between monomeric and filamentous myosin. The equilibrium in turn is governed by the state of phosphorylation of the 20-kD regulatory myosin light chain (MLC20, or RLC). It is known that phosphorylation of the myosin light chain favors formation of the filaments; it is not known how the light chain phosphorylation affects the lability of the filaments. The major aim of this thesis was to measure the mechanical integrity of the filaments formed from purified myosin molecules from bovine airway smooth muscle, and to determine whether the integrity was influenced by phosphorylation of the myosin light chain. Methods: Myosin was purified from bovine trachealis to form filaments, in ATP containing zero-calcium solution during a slow dialysis that gradually reduced the ionic strength. Sufficient myosin light chain kinase and phosphatase, as well as calmodulin, were retained after the myosin purification and this enabled phosphorylation of RLC within 20-40 s after addition of calcium to the filament suspension. The phosphorylated and non-phosphorylated filaments were then partially disassembled by ultrasonification. The extent of filament disintegration was visualized and quantified by atomic force microscopy. Results: RLC phosphorylation reduced the diameter of the filaments and rendered the filaments more resistant to ultrasonic agitation. Electron microscopy revealed a similar reduction in filament diameter in intact smooth muscle when the cells were activated. Conclusion: Our results suggest that RLC phosphorylation is a key regulatory step in modifying the structural properties of myosin filaments in smooth muscle, where formation and dissolution of the filaments are required in the cells’ adaptation to different cell length.
46

A LOW COST 2-AXIS PLC CONTROLLED FILAMENT WINDING MACHINE WITH SIMPLIFIED FIBER WINDING ANGLE AND TENSION CONTROL SYSTEM

Hazra, Trinankur 17 March 2011 (has links)
Designing a filament winding machine involves two major components. First component is the designing of the mechanism which delivers appropriate winding pattern as specified by the user (i.e. the winding angle). The second component is the realization of an effective fiber tensioning system for ensuring consistent overall consolidation. Today, there exist a variety of sophisticated methods to achieve both these parameters; however the implementation of these techniques increases the price of a winding machine, making its acquisition very difficult for small scale applications. Sophisticated winding machine includes higher number of degrees of freedom, and high end CNC controlled algorithms. However for creating axi-symetric products with constant diameter, only a 2-axis winding is sufficient. On this note a novel cost effective method for fiber winding angle control and fiber winding tension control is designed, simulated, implemented into a low cost prototype 2-axis filament winding machine, and the scope for its? further improvement has also been discussed. The system designed, uses a cost effective PLC as the centralized controller of the system for implementing both fiber winding control and tension control through PID control. A novel actuator for tension control is designed and implemented. Also a comparison between the conventional PI controller and a Mamdani type Fuzzy inference based control system for controlling the fiber tension is made. In this process a novel technique for making PI controller capable of handling known nonlinearities in the system is introduced. Experimental system responses of the designed prototype are analyzed.
47

Construction of a single-chain antibody against intermediate filaments

Rutherford, Sharon Ann January 1994 (has links)
Intermediate filaments are fibrous proteins, appearing in a wide variety of tissue specific forms. The function of these proteins is poorly understood, although they are commonly believed to perform a structural role in the cell. Evidence suggests that the role these proteins play may be more dynamic than was previously believed. To gain more insight into their normal in vivo function, a single-chain monoclonal antibody has been constructed to serve as a specific reagent which can disrupt the intermediate filament network in vivo. The work presented in this thesis represents the first step in an approach which involves the use of single-chain monoclonal antibodies as specific reagents to target and disrupt the function of intracellular proteins. / The polymerase chain reaction was used for the cloning and modification of the heavy and light chain variable regions of the murine monoclonal antibody produced by the TIB 131 hybridoma. The variable regions of the light and heavy IgG chains were initially amplified from cDNA using degenerate 5$ sp prime$ primers and 3$ sp prime$ primers complementary to the constant region of the appropriate chain. The amplification products were cloned individually, sequenced, then modified to include restriction sites suitable for cloning into an expression vector. The two modified variable regions were cloned into an expression vector, and when expressed in either bacteria or in a rabbit reticulocyte lysate system, yielded a protein of the expected molecular weight.
48

Identification and characterization of gap junction-associated proteins phosphorylated in RSV-infected fibroblasts

Crow, David Scott January 1990 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. / Includes bibliographical references (leaf 80) / Microfiche. / viii, 80 leaves, bound ill. 29 cm
49

Molecular components and organelles involved in calcium-mediated signal-transduction in Paramecium

Sehring, Ivonne Margarete. January 2006 (has links)
Konstanz, Univ., Diss., 2006.
50

Das survival of motoneuron (SMN) Protein und axonales Wachstum : Bedeutung für die molekulare Pathologie der spinalen Muskelatrophie

Bergeijk, Jeroen van January 2007 (has links) (PDF)
Hannover, Univ., Diss., 2007

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