Browsing by Issue Date, starting with "2006-11-20"

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Optical characteristics and microstructure of ZnO quantum dots-SiO2 nanocomposite films prepared by sputtering methods
(2006-11-20)
Peng, Yu-Yun
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Hsieh, Tsung-Eong
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Hsu, Chia-Hung
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材料科學與工程學系
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Department of Materials Science and Engineering
ZnO quantum dots (QDs)-SiO2 nanocomposite films were prepared using the target-attached radio-frequency sputtering. The transmission electron microscopy revealed the uniform dispersion of ZnO QDs with diameters about 2-7 nm in amorphous SiO2 matrix. The photoluminescence showed that small ZnO QDs are able to emit white light with luminescence spectra similar to those of the present GaN-based light emitting diode (LED). The calculated chromaticity coordinates of emitting light evidenced the feasibility of ZnO QDs-SiO2 nanocomposite films as the fluorescence material in optoelectronic devices. (c) 2006 American Institute of Physics.
Using a novel sulfonated silica nanoparticles for Nafion (R) membrane for direct methanol fuel cell
(2006-11-20)
Su, Yu-Huei
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Wei, Tung-Yu
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Hsu, Chih-Hao
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Liu, Ying-Ling
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Sun, Yi-Ming
Analysis of filling of an oval disk-shaped chamber with microfluidic flows
(2006-11-20)
Chen, J. J.
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Liu, W. Z.
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Lin, J. D.
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Wu, J. W.
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機械工程學系
The filling of an oval disk-shaped micro-chamber by liquid is analyzed with reference to micro-systems with inlets and outlets of various widths, which are fabricated using MEMS technology. The results concern the motion of the gas-liquid interface. The flow fields during the filling of the micro-chambers are also studied. During the filling, the front shape is determined by the competition among inertia, adhesion and surface tension. The effects of non-dimensional parameters, such as the Reynolds number and the Weber number, both determine by the inlet velocity, as well as the wall adhesive conditions, on the flow characteristics are examined. The effects of the widths of channels in a circular chamber and the lengths of the semi-major and semi-minor axes of an oval chamber on the filling process are also investigated. Geometric changes alter the angle between the microchannels and the micro-chamber at their intersection and significantly affect the filling of the micro-chamber with the liquid. The location of bubble entrapment is plotted parametrically against the Weber number, the liquid/substrate contact angle and the change in the angle between the microchannels and the micro-chamber at intersection. Evidently, air is entrapped when the inertia is high, large changes in the angle between the channels and the chamber at the intersection are made, and a hydrophobic property is observed inside the chamber wall. The numerical results are also compared with experimental measurements; they indicate similar filling processes. (c) 2006 Elsevier B.V. All rights reserved.
Conformation-networks of two-dimensional lattice homopolymers
(2006-11-20)
Luo, Yu-Pin
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Lin, Hung-Yeh
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Huang, Ming-Chang
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Liaw, Tsong-Ming
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電子物理學系
The effect of different Monte Carlo move sets on the folding kinetics of lattice polymer chains is studied from the geometry of the conformation-network. The networks have the characteristics of small-world: the local connections are more clustered than that of the corresponding random lattices, and the characteristic path lengths increase logarithmically with the number of nodes. One of the elementary moves, rigid rotation, has drastic effect on the geometric properties of the network. The move increases greatly the connections and reduces significantly the shortest path lengths between conformations. Including rigid rotation to the move set results in the increase of the dimensionality of the conformation space to the value about 4. (c) 2006 Elsevier B.V. All rights reserved.
Capping the upper and lower rims of calix[4]arenes by aryl dinitrile oxide reactions
(2006-11-20)
Shiao, Ya-Jiun
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Chiang, Pei-Chen
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Senthilvelan, Annamalai
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Tsai, Ming-Tsung
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Lee, Gene-Hsiang
1, 3-Dipolar cycloadditions of upper- and lower-rim diallylcalix[4]arenes (1 and 3) with aryl dinitrile oxides provide a unique and efficient way of capping the calix[4]arenes. When dinitrile oxides reacted with 5-allylcalix[4]arene 7, they underwent a 1,3-dipolar cycloaddition on one side and an electrophilic substitution on the other side, which led to a novel type of asymmetric calix[4]arenes (9 and 12). (c) 2006 Elsevier Ltd. All rights reserved.
Regular honeycomb porous polymer films based on amphiphilic block copolymer
(2006-11-20)
Tung, Pao-Hsaing
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Huang, Chih-Feng
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Chen, Shih-Chien
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Hsu, Chih-Hao
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Chang, Feng-Chih
藉由流體雷諾數原理操控之致動器及其製造方法與操作方法
(2006-11-21)
徐琅
;
劉承賢
;
張晃猷
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彭慧玲
;
張傑
一種藉由流體雷諾數原理操控之致動器，其包括數條固定電極，配置在一基板上；一絕緣層，形成於基板上且覆蓋住上述之固定電極；以及數條可動電極，對應配置於上述固定電極上方之絕緣層上，其中上述之可動電極的一端係固定於絕緣層上，而另一端則遠離絕緣層，以使可動電極向上翹曲。
利用晶體成長過濾基板而進行鎳誘發非晶矽結晶
(2006-11-21)
吳耀銓
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胡國仁
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賴育銘
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侯智元
本發明關於利用鎳誘發非晶矽結晶方法而製造出大的多晶矽顆粒，其利用背面預先鍍上Ni之矽晶圓當做Ni的晶種層以控制Ni擴散的數量，及採取壓印技術以控制多晶矽成長之成核位置，而製造出大的多晶矽顆粒。
Transient analysis of water transport in PEM fuel cells
(2006-11-22)
Yan, Wei-Mon
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Chu, Hsin-Sen
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Chen, Jian-Yao
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Soong, Chyi-Yeou
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Chen, Falin
This paper theoretically studies the water transport phenomena in PEM fuel cells, mainly investigating the transient behavior in the gas diffusion layer (GDL), catalyst layer (CL) and proton exchange membrane (PEM). In the PEM, both diffusion and electro-osmosis processes are considered, while in the GDL and CL, only diffusion process is taken into account. The process of water uptake is employed to account for the water transport at the interface between the PEM and CL. The results indicate that the water content in the PEM and the time for reaching the steady state in the start-up process are influenced by the humidification constant, k, the humidification, and the thickness of PEM. The rise of the k increases the water content in the membrane and shortens the time for reaching the steady state. Insufficient humidification causes relatively small water content and long steady time. When the PEM is thinner, the water is more uniformly distributed, the water content gets higher, and the time for reaching the steady state is distinctly shorter. (c) 2006 Elsevier B.V. All rights reserved.
Study on fatigue and breakdown properties of Pt/(Pb,Sr)TiO3/Pt capacitors
(2006-11-22)
Wang, Jyh-Liang
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Lai, Yi-Sheng
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Chiou, Bi-Shiou
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Tseng, Huai-Yuan
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Tsai, Chun-Chien
Pulsed- laser deposited ( Pb, Sr) TiO3 ( PSrT) films on Pt/ SiO2/ Si substrate at various ambient oxygen pressures ( P-O2) are investigated in this work. Films deposited at P-O2 below 100 mTorr exhibit the ( 100) preferred orientation and a tetragonal structure with larger tetragonality. In addition, films deposited at 80 mTorr exhibit the most apparent ferroelectric properties in contrast to those deposited at 200 mTorr. Moreover, films deposited at higher P-O2 also exhibit longer lifetimes and higher breakdown fields due to their smaller leakage current density, in terms of the reduction of defects, compensation of oxygen vacancies (OVs), an improved interface and small cluster sizes. An energy band model reveals that fatigue properties of PSrT films are dominated by interfacial states at low P-O2 and by deep trapping states at high P-O2, which could be ascribed to OVs located at the interfaces and inside films, respectively.
Synthesis of laterally attached side-chain liquid crystalline poly(p-phenylene vinylene) and polyfluorene derivatives for the application of polarized electroluminescence
(2006-11-22)
Yao, Yung-Hsin
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Yang, Sheng-Hsiung
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Hsu, Chain-Shu
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應用化學系
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Department of Applied Chemistry
Two series of poly(p-phenylene vinylene) and polyfluorene derivatives (PPV1-PPV4 and PF1-PF5) containing laterally attached penta(p-phenylene) mesogenes were synthesized and characterized. These polymers show nematic liquid crystalline behavior. The optical properties of the polymers were investigated by UV-vis absorption and photoluminescence spectrometers and these polymers were fabricated to form the polarized electroluminescent devices using poly(ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT-PSS) as an alignment layer. In the series of poly(p-phenylene vinylene) derivatives, polymer PPV4 offered the best EL device performance. It emitted yellow light at 588 nm at 4 V The maximum brightness was about 1337 cd/m(2) at 9 V with a polarized ratio of 2.6. In another series of polyfluorene derivatives, PF4 offered the best EL device performance with the polarized ratio of 12.4 and a maximum luminescence of 1855 cd/m(2). In the case of polarized white light, as a consequence of blending small amount of PF4 and PF5 with a host polymer PF2, polarized ratio of up to 10.2 and a maximum brightness of 2454 cd/m(2) have been attained. The aligned films exhibited pronounced polarized ratio, implying that the polymers exhibit potential for linearly polarized LED application. (c) 2006 Elsevier Ltd. All rights reserved.
Method for sequentially writing fiber bragg grating by using real-time side-diffraction optical fiber position monitoring
(2006-11-23)
Hsu, Kuei-Chu
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Sheu, Lih-Gen
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Chuang, Kai-Ping
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Chang, Shu-Hui
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Lai, Yinchieh
The present invention provides a fiber Bragg Grating sequential writing method with real-time optical fiber position monitoring, characterized in that the relative phase between a fiber grating and a writing interference beam at each positioning point is determined by an interferometric side-diffraction method, and writing is sequentially performed. Accuracy in fabricating a long and complex fiber grating structure can be increased by decreasing or avoiding accumulative errors caused by long-term scan of monitoring optical fiber position, or by a means for fabricating a wanted reference fiber Bragg grating with similar settings.
Method and apparatus for selecting intra prediction mode
(2006-11-23)
Cheng, Chao-chung
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Chang, Tian-sheuan
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Tsai, Chi-ken
A method for selecting intra prediction mode includes: calculating an error value for each of the prediction modes in a first group, wherein the first group includes two prediction modes where an included angle between their prediction directions is the largest; calculating an error value for each of the prediction modes in a second group, wherein the prediction modes in the second group refer to the prediction modes with prediction directions near the two sides of the prediction direction of the prediction mode with smaller error value in the first group; calculating an error value for the prediction mode in a third group, wherein the prediction mode in the third group is the prediction mode with prediction direction adjacent to the prediction direction of the prediction mode with smaller error value in the second group; calculating a DC prediction mode in the plurality of prediction modes; and among the prediction modes with calculated error values, selecting a prediction mode with a smallest error value to be the intra prediction mode for encoding the subblock.
Dual-mode high throughput de-blocking filter
(2006-11-23)
Lee, Chen-Yi
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Liu, Tsu-Ming
This invention provides the unique and high-throughput architecture for multiple video standards. Particularly, we propose a novel scheme to integrate the standard in-loop filter and the informative post-loop filter. Due to the non-standardization of post filter, it provides high freedom to develop a certain suitable algorithm for the integration with loop-filter. We modify the post filter algorithm to make a compromise between hardware integration complexity and performance loss. Further, we propose a hybrid scheduling to reduce the processing cycles and improve the system throughput. The main idea is that we use four pixel buffers to keep the intermediate pixel value and perform the horizontal and vertical filtering process in one hybrid scheduling flow. In our approach, we reduce processing cycles, and the synthesized gate counts are very small. Meanwhile, the synthesized results also indicate lower cost for hardware.
Deblocking filtering method used on video encoding/decoding and apparatus thereof
(2006-11-23)
Cheng, Chao-chung
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Chang, Tian-sheuan
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Lin, Tien-hung
A deblocking filtering method used on video encoding/decoding includes: sequentially reading the subblocks adjacent to a vertical edge according to a deblocking direction, and performing a deblocking process on the vertical edge; performing a transposition on the pixel data of a current subblock; performing the deblocking process on a parallel edge of the current subblock, and outputting the pixel data of another subblock adjacent to the parallel edge after transposition; sequentially storing a plurality of current subblocks; transposing and outputting the pixel data of the plurality of current subblocks after completion of the deblocking of the current macroblock.
A computational study on the decomposition of NH4ClO4: Comparison of the gas-phase and condensed-phase results
(2006-11-24)
Zhu, R. S.
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Lin, M. C.
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交大名義發表
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National Chiao Tung University
The decomposition of NH4ClO4 (AP) in both gaseous and condensed phases has been studied at the CCSD(T)/6-311 + G(3df,2p)// B3LYP/6-311 + G(3df,2p) level. Formation of NH3 + HClO3 is the main channel in the gas phase with 14.2 kcal/mol enthalpy change. In solution, the enthalpy change for this channel is 29.5 kcal/mol, which is close to the sublimation activation energy, similar to 30 kcal/mol in crystalline AP. Formation of H3N-HO +ClO3 has higher enthalpy changes, 56.3 kcal/mol and 77.1 kcal/mol in the gas phase and in solution, respectively. Strong solvent effects may exist in the AP decomposition reaction. (c) 2006 Elsevier B.V. All rights reserved.
Characterization of the type 3 fimbriae with different MrkD adhesins: Possible role of the MrkD containing an RGD motif
(2006-11-24)
Huang, Ying-Jung
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Wu, Chien-Chen
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Chen, Mei-Chen
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Fung, Chang-Phone
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Peng, Hwei-Ling
Four novel mrkD alleles namely mrkD(V1), mrkD(V2), mrkD(V3), and mrkD(V4) were identified in seventeen Klebsiella pneuntoniae meningitis strains using PCR-RFLP and sequence determination. Comparative analysis revealed a most variable region containing an RGD motif in the receptor domain of MrkD(V3). In order to determine if the sequence confers the K pneumoniae mrkD(V3) the highest level of the fimbrial activity, a type 3 fimbriae display system was constructed in Escherichia coli. The E coli JM 109[pmrkABCD(V3)F] displaying meshwork-like fimbriae also had the most fimbrial activity, supporting a possible role of the varied sequences. In a dose-dependent manner, the GRGDSP hexapeptide appeared to inhibit the adhesion of the E. coli JM109[pmrkABCD(V3)F] to HCT-8, an ileocecal epithelial cell line. In addition, the adhesion activity was reduced by the addition of anti-alpha 5 beta 1 integrin monoclonal antibody, indicating that the RGD containing region in MrkD(V3) is responsible for the binding of type 3 fimbriae to integrin. (c) 2006 Elsevier Inc. All rights reserved.
Composite lattice pattern formation in a wide-aperture thin-slice solid-state laser with imperfect reflective ends
(2006-11-24)
Otsuka, Kenju
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Miyasaka, Yoshihiko
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Narita, Tatsuro
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Chu, Shu-n Chu
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Lin, Chi-Ching
We observed self-formations of multiple lasing channels and two-dimensional lasing patterns consisting of composite local modes having different lasing frequencies in a laser-diode-pumped wide-aperture thin-slice solid-state laser with imperfect reflective end surfaces. Global patterns resembling higher-order Hermite-Gaussian modes or possessing N-fold rotational symmetries were experimentally shown to appear due to the standard polished surface roughness of closely spaced reflective ends and nonlinear modal interactions.
Field emission characteristics of chromium carbide capped carbon nanotips
(2006-11-25)
Hsu, C. H.
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Chen, C. F.
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Lo, H. C.
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材料科學與工程學系
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Department of Materials Science and Engineering
In this study, field emission characteristics of two carbon based nanomaterials, carbon nanotips and chromium carbide capped carbon nanotips, were discussed. Both of these materials were synthesized by bias-assisted microwave plasma chemical vapor deposition with hydrogen and methane as reactants. Ultra-sharpness of the carbon nanotips and the composite structure of chromium carbide capped carbon nanotips have shown unique structural and electrical properties. I-V measurements were carried out to investigate the field emission characteristics. The chromium carbide capped carbon nanotips showed superior field emission stability compared to carbon nanotips under constant current emission. (c) 2006 Elsevier B.V. All rights reserved.
High-performance polycrystalline silicon thin-film transistors with oxidenitride-oxide gate dielectric and multiple nanowire channels
(2006-11-25)
Chen, Shih-Ching
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Chang, Ting-Chang
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Liu, Po-Tsun
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Wu, Y. C.
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Tsai, C. C.
This work presents a method to enhance the performance of polycrystalline silicon thin film transistors (poly-Si TFTs) by using an oxide-nitride-oxide (ONO) gate dielectric and the multiple nanowire channels structure. Experimental results indicate that the performance of the device was enhanced by using the ONO multilayer, because the ONO gate dielectric constant is increased compared to the conventional oxide gate dielectric. Additionally, the TFTs with a ten nanowire channel structure (NW-TFTs) have superior electrical characteristics compared to other TFTs. This is because a structure with more corners and a shorter radius has better gate control due to the corner effect. (c) 2006 Elsevier B.V. All rights reserved.