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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.
111

The Study on Integration Strategy of Medical Device Industry in Taiwan ¡V The Case of the Joint Venture Project between Excelsior and Sinopharm

Wang, Kuan-Ju 30 July 2012 (has links)
Up to date, the biggest challenge of Taiwan¡¦s medical device industry is that the major market was occupied by international companies which directly hold the research and development, manufacture and selling. In addition, the medical devices have the properties in producing few products with diverse forms, research and development with complicating technology and high threshold in the application of product license. As the domestic market in Taiwan is quite small, small and medium-sized enterprises are the mainscales of Enterprises' Operating Capacity here. The chosen of joint venture of two enterprises through strategic cooperation may be one solution to survive in such ecology and play their good in order to create the core value supporting the goal of sustainability for business management. According to the policy considerations, the biotechnology and medical treatment industry are as the important issue in ECFA agreement between Taiwan and mainland China in 2010. All together, there are hundreds and thousands of opportunities for merger, acquisitions and strategic alliance within this industyin the foreseeable future. This study was based on the study case of the 32-years-old Excelsior. It began with dialysis market-oriented industry and then branched out into all the medical equipment industry. Through strategic co-operation, it expanded to become a medical integration platform providing services regarding to comprehensive roles from trade to hospital management. It accommodates the full range of downstream applications for Medical Engineering Services, Pharmaceutical warehousing and logistics, Procurement and supply, and health care management. Although the Excelsior has been to China ten years ago, it fails to succeed and returns back. In 2011, Excelsior makes the joining venture cooperates with the biggest pharmaceutic distributor in China, Sinopharm focuses on four major medicalterritory that are dialysis, medical cosmetic, dentistry and health-check, and approaches the 5000 billion market in Health-Care-Reform offered by the 12th-Five year-plan of China. However, this time it attempts a come back to become the most valuable of the integrated medical and health industry in Asia. Through study on the history and outcome of joining venture between Excelsior and Sinopharm in the field of medical device industry, this thesis addresses factors that will affect business innovation integrated and product line expression. Through studying the case of Excelsior on its background, history of Strategic cooperation¡B integrated product line¡Bfinancial management and experience of success or failure in the past may provide the reference for the development of Taiwan medical device industry.
112

Role of AI-2 in oral biofilm formation using microfluidic devices

Kim, Sun Ho 15 May 2009 (has links)
Biofilms are highly organized bacterial structures that are attached to a surface. They are ubiquitous in nature and may be detrimental, causing numerous types of illnesses in living organisms. Biofilms in the human oral cavity are the main cause of dental caries and periodontal diseases and can act as a source for pathogenic organisms to spread within the body and cause various types of systemic diseases. Streptococcus mutans is the primary etiological agent of dental caries, the single most chronic childhood disease. In many cases, quorum sensing (QS) is required for initial formation and subsequent development of biofilms and the signaling molecule autoinducer 2 (AI- 2) has been well studied as an inter-species QS signaling molecule. However, recent reports also suggest that AI-2-mediated signaling is important for intra-species biofilm formation in both Gram-negative and positive bacteria. Therefore, there is significant interest in understanding the role of different QS signals such as AI-2 in oral biofilm formation. Microfluidic devices provide biomimetic environments and offer a simple method for executing multiple stimuli experiments simultaneously, thus, can be an extremely powerful tool in the study of QS in biofilms. In this study, we report conditions that support the development of S. mutans biofilms in microchannel microfluidic devices, and the effects of extracellular addition of chemically synthesized (S)-4,5-dihydroxy-2,3-pentanedione (DPD; precursor of AI-2) on mono-species S. mutans luxS (AI-2 deficient strain) biofilm formation using a gradient generating microfluidic device. S. mutans wild type (WT) and luxS biofilms were developed in nutrient rich medium (25% brain heart infusion medium, BHI + 1% sucrose) for up to 48 h. Maximum biofilm formation with both strains was observed after 24 h, with distinct structure and organization. No changes in S. mutans luxS biofilm growth or structure were observed upon exposure to different concentrations of AI-2 in a gradient generating device (0 to 5 M). These results were also validated by using a standard 96-well plate assay and by verifying the uptake of AI-2 by S. mutans luxS. Our data suggest that extracellular addition of AI-2 does not complement the luxS deletion in S. mutans with respect to biofilm formation.
113

Study on semiconductor devices by high density plasma chemical vapor deposition

Chen, Yu-Ting 08 July 2005 (has links)
In this thesis, high density plasma chemical vapor deposition (HDPCVD) is used to fabricate novel multiple quantum well structure of light emitting diodes (LEDs) and charge storaged layers of SONOS nonvolatile semiconductor memories (NVSMs). On the study of the light emitting diodes (LEDs) technology, wide band gap hydrogenated amorphous silicon carbide and porous silicon carbide has blue or green luminescence are currently being investigated for applications in optoelectronic devices. However, due to the indirect band gap character, the quantum efficiency of these LEDs is very low. In our experiment, we fabricate 5-periods hydrogenated amorphous silicon carbide multiple quantum well structure to enhance the luminescence efficiency. In our study, there are some following notable features: (1) The a-SixC1-x multiple quantum well structure prepared by high density plasma chemical vapor deposition and it shows visible photoluminescence at room temperature. (2) After fluorine ions implantation and thermal annealing, The PL energy of a-SixC1-x multiple quantum well shift to high energy. (3) The PL intensity of SiO2-barrier SixC1-x multiple quantum well is larger than SiNx-barrier. (4) The film adheres well to glass or Si wafer even at low deposition temperature, e.g. 200 0C by high density plasma chemical vapor deposition. On the study of the silicon-oxide-nitride-oxide-silicon (SONOS) nonvolatile semiconductor memories (NVSMs) technology, the SONOS is a multi-dielectric device consisting of an oxide-nitride-oxide (ONO) sandwich in which charge storage takes place in discrete traps in the silicon nitride layer. In addition to silicon nitride as the storage layer, we have studied the oxide/SiC:O/oxide sandwiched structures and thermal oxidation of SiC layer as a storage layer by HDPCVD processes. In our study, there are some following notable features: (1) From the capacitance-voltage and current-voltage characteristics of oxygen-incorporated silicon carbide with different oxygen content, it is observed that the memory window is decreased with increasing the oxygen content. By controlling the oxygen content, a higher breakdown voltage can be achieved. (2) In the study of the oxidation of SiC, it is found that low temperature (800 ¢J) oxidized SiC shows a larger memory window than that of the high temperature (925 ¢J) oxidized SiC by high density plasma chemical vapor deposition.
114

Design and construction of a left ventricular cardiovascular assist device

Vedi, Manmeet Singh 15 November 2004 (has links)
Congestive heart failure (CHF) is a debilitating condition that afflicts 4.8 million Americans with an increasing incidence. Each year, there are an estimated 400,000 new cases. The incidence is on the rise as the age of the population is increasing and because most people are surviving their first heart attack. Pharmacological therapies are improving, yet many patients still reach end-stage heart failure and there are too few donor hearts available. This thesis is presented as a first small step in a long process in the design and development of a novel cardiac assist device that would ultimately heal a diseased heart by the process of ventricular recovery. The device acts to restore the kinematics of a diseased heart by modulating the extra ventricular displacements. The first surgery / trial were conducted on a bovine at the Veterinary School at Texas A&M University. Main objectives of the surgery were to test the method of attachment of the device and power requirements of the device. Details regarding the design and construction of the device have been presented in the thesis.
115

Design of mold to yield elastomeric membrane whose shape and size, when inflated, is similar to the shape of the human heart

Lagu, Amit Vinayak 15 November 2004 (has links)
Nearly five million Americans are living with heart failure and 550,000 new cases are diagnosed each year in the US. Amongst the new approaches to develop a better solution for Congestive Heart Failure, Ventricular Recovery (VR) holds the most promise. A team, under the guidance of Dr. Criscione in the Cardiac Mechanics Lab at Texas A&M University, is currently developing an investigative device which aims to assist in VR by restoration of physiological strain patterns in the myocardial cells. The contribution of this thesis has been towards the development of a molding apparatus that yields a polymeric membrane whose shape, when inflated, is similar to the shape of the human heart. This membrane would surround the epicardial surface of the heart, when used for the device being discussed and in particular for the prototypes being developed. Contribution also includes a testing apparatus that measures the inflation of a membrane and simulation to predict the behavior of isotropic ellipsoids upon inflation. After unsuccessful implementations of two processing techniques, the successful design, fabrication implementation and attachment method meets the design criteria and is based on a thermoforming technique. Inflation profiles for membranes developed using this technique were studied at different pressures, with the axis length as variable. At 1kpa, which is the normal coronary arterial pressure, the membrane with an axis length of 140mm was found to show a shape which is similar to the shape of the human heart. In order to better understand and predict the shape an isotropic ellipsoidal membrane would take upon inflation without experimentation, simulations were carried out. Successful conversion of ellipsoidal geometry, with a few degrees of freedom as parameters, aided in simulation.
116

The study of full color display based on white polymer light-emitting devices combined with color filters

Huang, Tang-chen 25 January 2008 (has links)
In consideration of fabrication and cost issue, lately White Organic Light-Emitting Device (WOLED) combined with Color Filter (CF) has become one of promising methods to produce full-color OLED displays. This method adopts the same light source so the lifetime and brightness of Red¡BGreen and Blue emissions are similar and there is no concern for color distortion. In addition, there is no mismatch issue of shadow mask alignment during fabrication. This method not only improve the resolution but also be able to make large size FPD (Flat Panel Displays). In this study, we fabricate White Polymer Light-Emitting Device (WPLED) on custom-built CF, and discuss its full-color characteristics after integration. This study contains four portions: 1.)Fabrication and electro-optical analysis of WPLED on ITO glass 2.)Electro-optical analysis of CF glass 3.)Optical simulation¡GEL(Light-Emitting) spectra of WPLED combined with transmissive spectra of CF 4.)Fabrication and electro-optical analysis of WPLED on CF glass
117

Design and Modeling of Planar Transformer-based Integrated Passive Devices

Wei, Tzu-Chiang 26 July 2008 (has links)
This thesis is mainly composed of two parts. The first part is to introduce the planar transformer-based circuits and their applications. The mixed-mode S parameters and the grounding effects for planar transformers are discussed. A physical model has been developed for modeling the planar transformers. In the second part, a new coil winding technique for planar transformers has been presented to realize a high-efficiency planar transformer with arbitrary turn ratio for power-split/combine and phase-shift applications. Especially, the power-split/combine architecture based on a planar transformer of cellular shape is first presented in this thesis, enabling various kinds of passive components to be widely realized using the integrated passive device processes. As an example, this thesis proposes a design procedure for high-efficiency balun component. Firstly, design a high Q transformer that considers the load impedance effects. Secondly, design the ground reference for un-balanced signal on the virtual ground symmetry axis for balanced signals. Thirdly, design impedance matching networks for minimizing un-balanced and balanced port return losses. Then, a high performance planar transformer-based balun design can be done.
118

The Study of ZnO/Si Layered SAW Oscillator for UV Detection

Cheng, Po-Shu 15 August 2008 (has links)
The highly c-axis oriented ZnO films were deposited on silicon substrates by reactive RF magnetron sputtering in this study. The optimal two-step deposition parameters for ZnO films, which are oxygen concentrations of 70 % (1st step) and 50 % (2nd step), RF power of 100 W and sputtering pressure of 25 mTorr, are obtained by means of XRD, SEM and AFM analysis. Al films are deposited under optimal deposition parameters, which are DC power of 100 W and sputtering pressure of 4 mTorr, to form IDT electrodes with low sheet resistances. Therefore, Al/ZnO/Si layered SAW devices were fabricated under these optimized manufacturing parameters. An oscillator based on a Al/ZnO/Si layered SAW device was fabricated for the application of UV detection and then investigating the acoustoelectric effect between surface acoustic wave and ultraviolet light illumination. Due to the fact that the sensor sensitivity is directly proportional to the resonance frequency, in this study the SAW device with high resonance frequency of Sezawa mode is adopted to form SAW oscillator for high sensitivity. The resonance frequency of SAW oscillator is 751.41 MHz. The optimal detecting zone for UV light is the center of IDT electrode with maximum sensitivity of 8.12 ppm/(£gW/cm2).
119

Fabrications and Characteristics of Nonvolatile Memory Devices with Sn Nanocrystals Embedded in MIS Structure

Chen, Chao-Yu 26 June 2009 (has links)
Current requirements of nonvolatile memory (NVM) are the high density cells, low-power consumption, high-speed operation and good reliability for the scaling down devices. However, all of the charges stored in the floating gate will leak into the substrate if the tunnel oxide has a leakage path in the conventional NVMs. Therefore, the tunnel oxide thickness is difficult to scale down in terms of charge retention and endurance. The nanocrystal nonvolatile memories are one of promising substitution, because the discrete storage nodes as the charge storage media have been effectively improve data retention under endurance test for the scaling down device. Many methods have been developed recently for the formation of nanocrystals. Generally, most methods need thermal treatment with high temperature and long duration. This procedure will influence thermal budget and throughput in current manufacture technology of semiconductor industry. And supercritical carbon dioxide (SCCO2) has been researched to the passivation of dielectric and reducing the activation energy. The research estimates SCCO2 is potential to form nanocrystals for these reason. This research is to discuss the feasibility of fabricating nanocrystal NVMs device with low temperature SCCO2. The low melting point metal material Sn is used for the attempts. In order to check if Sn can be used for fabricating nanocrystal NVMs device, the research selects the conventional thermal annealing method first. It uses rapid thermal annealing to improve the crystalline of nanocrystals and reliability of the memory device. Compare to different Sn containment or chemistry and different process, analyze the electric characteristics and materials chemistry. At last, select the Sn and SiO2 co-sputtering film to try the SCCO2 process and analyze these characteristics as well. Due to the novel technology, many physical mechanism and improvement of properties will be discuss following.
120

Antenna for Integrated Passive Device

Tsai, Cheng-han 24 July 2009 (has links)
In this thesis, the study focuses on the antenna design for integrated passive devices. By using the substrate of piezoelectric material with high permittivity and introducing the fractal structures, the size reduction is obtained. Part of the research analyzes the influences of the surrounding environment on the antenna performances, including the effects of external formations, internal components, and interconnections. The results can provide the design rules for developing IPD antennas. The other part of the research emphasizes the design of IPD antenna itself, involving the investigations on the characteristics of substrate and fractals. The trade-off between compactness and radiation efficiency is pointed out, and then a design of modified ground plane is presented. When the modified design is placed on the system ground plane that exists in real system, the radiation efficiency can be improved significantly. Therefore, the concept of the compact IPD antenna is achieved.

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