Browsing by Issue Date, starting with "2003-12-02"

Now showing 1 - 20 of 72113

Synthesis and dielectric properties of polyimide-tethered polyhedral oligomeric silsesquioxane (POSS) nanocomposites via POSS-diamine
(2003-12-02)
Leu, CM
;
Chang, YT
;
Wei, KH
;
材料科學與工程學系
;
Department of Materials Science and Engineering
Polyimide-tethered polyhedral oligomeric silsesquioxane, (R7R'Si8O12) (POSS), nanocomposites with well-defined architectures are prepared by the copolymerization reaction of a new type of diamine monomer: POSS-diamine, 4,4'-oxydianiline (ODA), and pyromellitic dianhydride (PMDA). This type of polyimide-side-chain-tethered POSS nanocomposite presents self-assembly characteristics when the amount of POSS exceeds 10 mol %, as evidenced by transmission electron microscopy studies. Furthermore, POSS/polyimide nanocomposites have both lower and tunable dielectric constants, with the lowest value of 2.3, and controllable mechanical properties, as compared to that of pure polyimide.
Ferroelectric thin film processing for ferroelectric field-effect transistor
(2003-12-04)
Chen, San-Yuan
;
Chin, Albert
;
Sun, Chia-Liang
The present invention relates to a method for manufacturing a ferroelectric field-effect transistor, particularly to a ferroelectric field-effect transistor with a metal/ferroelectric/insulator/semiconductor (MFIS) gate capacitor structure. The method comprises steps of depositing a bismuth layered ferroelectric film on the insulator buffered Si, after a high-temperature thermal treatment, depositing an upper electrode on the bismuth layered ferroelectric film.
Chaos synchronization of a horizontal platform system
(2003-12-04)
Ge, ZM
;
Yu, TC
;
Chen, YS
;
機械工程學系
;
Department of Mechanical Engineering
Chaos and chaos synchronization of the horizontal platform system are studied in this paper. Because of the non-linear terms of the systems, the systems exhibit both regular and chaotic motions. By applying various numerical results, such as phase portraits, Poincare maps, time history and power spectrum analysis, the behaviors of the periodic and chaos synchronization are presented. The effects of the change of parameters in the system can be found in the bifurcation diagrams. Chaos synchronization of feedback methods in two coupled systems has been studied by Lyapunov exponent and coupling strength. Besides, phase effect of external excitations and the transient time in unidirectional synchronization also have been researched. (C) 2003 Elsevier Science Ltd. All rights reserved.
Experimental and numerical analyses on three-roll planetary rolling process
(2003-12-10)
Shih, CK
;
Hung, CH
;
機械工程學系
;
Department of Mechanical Engineering
This study conducts experiments on a planetary three-roll experimental apparatus and uses plasticine as the working material. Certain rolling characteristics were observed and compared with the data from finite element simulation, which include diameter of workpieces after deformation, the pitch length and threaded angle of spiral marks, and the cavity at the leading end of rolled plasticine. The comparison confirms the correctness of the simulation model for PSW. (C) 2003 Elsevier B.V. All rights reserved.
Method for calculating syndrome polynomial in decoding error correction codes
(2003-12-11)
Chang, Hsie-Chia
;
Lee, Chen-Yi
;
Lin, Chien-Ching
The present invention provides a method of calculating the syndrome polynomial in decoding error correction codes. From the relation between the syndromes and the coefficients of the error locator polynomial, the inference that the first t syndromes are zeros, then the next t syndromes are also zeros can be deduced, wherein t is the largest number of correctable errors. For all received codewords, the first t syndromes are calculated. Next, whether the first t syndromes are zeros is judged. If the first t syndromes are zeros, the computation is stopped; otherwise, the next t syndromes are calculated. Therefore, the present invention can judge whether the received codeword is erroneous with only a half of computation, hence effectively reducing the computation in practical operation and achieving the object of low power consumption.
解碼錯誤訂正碼時用以解答鍵方程式多項式之方法及其裝置
(2003-12-11)
李鎮宜
;
張錫嘉
在解碼時，通常為了錯誤訂正目的而將接收字碼經編碼處理。據此，一種在鍵方程式解答步驟中，用以計算錯誤定位器多項式和錯誤求值器多項式之一種方法，在本發明加以揭露。藉由本發明，多項式可經由多個中間步驟而產生，而上述步驟可由最少量之硬體線路來加以實施。中間步驟之數目需要一相對應之運算時間週期(cycle)數目，以完成多項式之計算。依所選擇之(N,K)碼而定，計算多項式所須之運算時間週期數目將是介於上游資料計算所須時間之內。特別的是，只須小數量之暫存器及有限場乘法器(FFM)，且不須有限場反轉器(FFI)之有效安排配置也加以揭露。使用這些新方法，僅使用4t+2ρ+4個暫存器，3個FFM且不須FFI之有效節省面積的架構也已揭示，用以實施由無反轉Euclidean演算法推導而得之方法。此外，所提出之架構也可用來求出Forney徵兆多項式。本發明之方法及其裝置可廣泛應用於各種具有適當編碼長度之RS碼和BCH碼，包括錯誤更正以及抹除更正之情況。
製造正負混合型光學補償膜之方法、正負混合型光學補償膜及使用它之液晶顯示元件或液晶顯示器
(2003-12-11)
吳龍海
;
許千樹
;
丁清華
本發明提供一種製造光學補償膜之方法，其係將碟狀液晶與棒狀液晶之液晶配方塗布位於基材之經定向處理的配向膜上，以高溫處理而得到具有碟狀液晶、棒狀液晶分子規則排列之薄膜，再利用紫外光予以聚合製成具有良好視角之正負型光學補償膜的方法；及提供由此種方法所製得之光學補償膜；以及提供一種具有光學補償膜之液晶顯示元件或液晶顯示器。
A novel cold-adapted imidase from fish Oreochromis niloticus that catalyzes hydrolysis of maleimide
(2003-12-12)
Huang, CY
;
Yang, YS
;
生醫工程研究所
;
Institute of Biomedical Engineering
In this paper we report the first comparative study of cold-adapted imidase (EC 3.5.2.2) from the fish (Oreochromis niloticus) liver and its thermophilic counterparts taken from pig liver and Escherichia coli (overexpressed recombinant hydantoinase from Agrobacterium radiobacter NRRL B1). Approximately 6000-fold purification and a 40% yield of fish imidase activity were obtained through ammonium sulfate precipitation, octyl, chelating, DEAE, and hydroxyapatite chromatography. This cold-adapted imidase was characterized by a specific activity 10- to a 100-fold higher than those of its thermophilic counterparts below room temperature (25 degreesC or lower) conditions but less stable at elevated temperatures (40 degreesC or higher). A less organized helical structure (compared to those of pig liver and bacterial imidases) was observed by circular dichroism. Furthermore, maleimide was first identified as a novel substrate of all imidases examined, and confirmed by HPLC and NMR analysis. These results constituted a first study to discover a novel cold-adapted imidase with surprising high activity. These findings might be also helpful for industrial application of imidase. (C) 2003 Elsevier Inc. All rights reserved.
祭大荒
(2003-12-15)
管管
Effect of low-temperature annealing on the luminescent lifetime and negative differential resistance of silicon-implanted borosilicate glass
(2003-12-15)
Lin, GR
;
光電工程學系
;
Department of Photonics
The silicon-implanted borosilicate glass (BSO:Si+) low-temperature (500 degreesC) annealed at a different time are structurally, electrically, and optically characterized. The weak and broadened x-ray diffraction reveal insignificant Si nano-crystallization even after long-term annealing, whereas the redshifted photoluminescence (PL) interprets the change in category and the decrease in density of irradiative defects in BSO:Si+. Time-resolved PL analysis reveals a lengthening luminescent lifetime of BSO:Si+ from 1.7 to 2.8 ns, which indicates that the density ratio of nonradiative defects in as-implanted BSO:Si+ are reduced by one-tenth after annealing for 60 min. Transmission line mode analysis shows that both the leakage current and the contact resistance of a metal-BSO:Si+-metal diode has dramatically changed by three orders of magnitude. A strong negative differential resistance (NDR) and associated double-barrier electron tunneling phenomenon are observed with a threshold electric field of 290-350 kV/cm. The decreasing barrier height of the metal-BSO:Si+ junction from 3.0 to 1.9 eV is mainly contributed by deep-level defects with activation energy of similar to1 eV. After annealing, the NDR effect significantly diminishes, the barrier height raises to >2.4 eV, and most electrical characteristics of the metal-BSO:Si+ junction have recovered back to be comparable with those of the metal-BSO junction due to the elimination of these defects. (C) 2003 American Institute of Physics.
祭大荒
(2003-12-15)
管管
祭大荒
(2003-12-15)
管管
祭大荒
(2003-12-15)
管管
Electron field emission from fluorinated amorphous carbon nanoparticles on porous alumina
(2003-12-15)
Lai, SH
;
Huang, KP
;
Pan, YM
;
Chen, YL
;
Chan, LH
The fluorinated amorphous carbon nanoparticles (a-C:F NPs) films have been prepared on a porous alumina at a lower temperature of similar to100 degreesC by an ECR-CVD system with a mixture of CF4, C2H2 and Ar as precursors. The morphology of a-C:F NPs films was verified by FESEM. The microstructure and chemical bonding nature of the a-C:F NPs films were investigated by Raman spectroscopy and XPS, respectively. The fluorinated samples need a lower field (similar to2.25 V/mum for 10.6% F a-C:F NPs films) to emit the electron than unfluorinated ones. The excellent field-emission properties of a-C:F NPs films are due to the effect of the shape, fluorine doping and dangling bonds. (C) 2003 Elsevier B.V. All rights reserved.
Electrical and dielectric properties of low-temperature crystallized Sr0.8Bi2.6Ta2O9+x thin films on Ir/SiO2/Si substrates
(2003-12-20)
Chou, HY
;
Chen, TM
;
Tseng, TY
;
應用化學系
;
電子工程學系及電子研究所
Ferroelectric thin films of bismuth layer structured compounds, Sr0.8Bi2.6Ta2O9+x (SBT) were deposited onto Ir/SiO2/Si substrates using metal organic decomposition (MOD) method. The crystallization of the SBT thin films annealed at various temperatures was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The polarization (P) versus electric field (E) characteristics exhibited a systematic variation from linear to non-linear polarization (hysteresis) with an increase in the annealing temperature of the SBT films. The leakage current density and dielectric constant of the SBT films were also strongly dependent on the annealing temperature, which in turn determined the grain size, mean surface roughness and inter diffusion through interfacial layers. The lowest leakage current density of 10(-9) A cm(-2) at 100 kV cm(-1) was obtained for SBT thin film annealed at 450 degreesC. The SBT thin films annealed at 650 and 700 degreesC remained fatigue-free up to 10 switching cycles. (C) 2003 Elsevier B.V. All rights reserved.
A novel low-temperature growth and characterization of single crystal ZnO nanorods
(2003-12-20)
Hung, CH
;
Whang, WT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
One-dimensional (1D) single crystal ZnO nanorods directly grown on ZnO nanostructured substrates by soft chemical method is proposed. Employing a novel two steps procedure, the ZnO nanorods with a diameter about 45 nm can be successfully grown on substrate in aqueous solution at attractive low temperature in 90 degreesC, permitting large-scale fabrication with a relatively low cost and a potential application in optoelectronic nanodevices. The structures, appearances and optical properties of ZnO nanorods also have been characterized. (C) 2003 Elsevier B.V. All rights reserved.
Doped red organic electroluminescent devices based on a cohost emitter system
(2003-12-22)
Liu, TH
;
Iou, CY
;
Chen, CH
;
應用化學系
;
光電工程學系
We have developed an efficient red emitter in organic light-emitting diodes based on the fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetra-methyljulolidyl-9-enyl)-4H-pyran doped in a cohost emitter system of 5,6,11,12-tetraphenylnathacene/tris(8-hydroxyquinolinato)aluminum which achieved an electroluminescence (EL) efficiency of 4.4 cd/A and 2.1 lm/W at 20 mA/cm(2) and 6.8 V, with a near saturated Commission Internationale d'Eclairage coordinates (x=0.65, y=0.35). This cohost emitter system has the advantage of alleviating the current-induced fluorescence quenching often encountered in red organic EL devices and greatly improves the EL efficiency over a wide range of drive current conditions. From accelerated degradation tests, a device half-life of about 33 800 h can be projected in this system at an initial device luminance of 100 cd/m(2). (C) 2003 American Institute of Physics.
Traceability on RSA-based partially signature with low computation
(2003-12-25)
Hwang, MS
;
Lee, CC
;
Lai, YC
;
資訊工程學系
;
Department of Computer Science
In this article, we show that the Chien et al.'s partially blind signature scheme based on RSA public cryptosystem could not meet the untraceability property of a blind signature. (C) 2002 Elsevier Inc. All rights reserved.
Partial wave analysis of scattering with nonlocal Aharonov-Bohm effect
(2003-12-29)
Lin, DH
;
應用數學系
;
Department of Applied Mathematics
Partial wave theory of a two-dimensional scattering problem for an arbitrary short range potential and a nonlocal Aharonov-Bohm magnetic flux is established. The scattering process of a "hard disk" like potential and the magnetic flux is examined. Since the nonlocal influence of magnetic flux on the charged particles is universal, the nonlocal effect in hard disk case is expected to appear in quite general potential system and will be useful in understanding some phenomena in mesoscopic physics. (C) 2003 Elsevier B.V. All rights reserved.
製備合成氧化物在互補式金氧半閘極介電層及自旋電元件應用之研究(III)
(2004)
趙天生
;
TIEN-SHENGCHAO
;
交通大學電子物理系