Browsing by Issue Date, starting with "2008-07-31"

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Design of low-voltage CMOS low-noise amplifier with image-rejection function
(2008-07-31)
Wei, L. -S.
;
Wu, H. -I.
;
Jou, C. F.
;
電信工程研究所
;
Institute of Communications Engineering
A new design is presented that combines a low-noise amplifier (LNA) with an on-chip. lter instead of external. lter to eliminate image signal based on TSMC 0.18 mu m CMOS technology. The fully integrated 5.9 GHz LNA exhibits 15.2 dB gain, 3.2 dB noise figure, better than -15 dB input and output return loss, and -27 dB image rejection. The circuit operates at a supply voltage of 1 V and consumes only 6.1 mW power.
Pre-charge sample-and-hold circuit
(2008-07-31)
Wu, Jieh-Tsorng
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Lee, Zwei-Mei
;
Wang, Cheng-Yeh
A precharge sample-and-hold circuit is formed by coupling a buffer with an input port and making use of a switch to conduct the circuit between the buffer and a total load capacitor for precharging according the state of a sample-and-hold circuit. When the sample-and-hold circuit is in the sample mode, it precharges the total load capacitor. When the sample-and-hold circuit is in the hold mode, the influence to the sampled signal is further reduced due to the precharging. The requirements of swing rate, output voltage swing, gain-bandwidth product for the opamps can therefore be reduced, hence being applicable to the realization of the design of advanced fabrication technologies of low supply voltages.
SELF-CALIBRATING HIGH-SPEED ANALOG-TO-DIGITAL CONVERTER
(2008-07-31)
SU, CHAU-CHIN
;
LU, HUNG-WEN
;
CHI, SHUN-MIN
A precisely self-calibrating high-speed analog to digital converter is disclosed, wherein the aspect ratios of tri-state inverters are adjusted to fine-tune threshold voltage as comparators. And the multiplexers composed of tri-state inverters amplify the signal from the output of comparators. Their switches of tri-state inverters may be properly controlled to select the optimal channels and reduce unnecessary power consumption. The calibration circuitry utilizes under-sampling to calculate the duty cycles of comparators, selecting the optimal comparators and channels. By the way, the invention may avoid process variation.
用於通訊系統的資料交換裝置及方法
(2008-08-01)
李鎮宜
;
陸志豪
;
林建青
;
張錫嘉
;
許雅三
一種用於通訊系統之資料交換裝置及方法,其主要係由一轉換電路接收一具有實際編碼尺寸的來源資料,以轉換為一具有容許編碼尺寸的轉換資料,藉由在轉換資料中設置判別位元來標示是否為來源資料。之後由一位移電路對轉換資料進行一位移量的位移以產生一位移資料,並由位移資料的最低位元及最高位元開始擷取實際編碼尺寸分別作為一第一資料及一第二資料,或者在第一資料的擷取方式上,改為由最高位元減去實際編碼尺寸的位元作為第一資料的起始位元,以從最低位元的方向擷取實際編碼尺寸。最後使用一比較及選擇電路比較第一資料及第二資料中相對應的判別位元,以輸出一輸出資料,其中輸出資料係來源資料位移了上述的位移量後的資料。
Synthesis and characterization of nanoporous SiO2/pHEMA biocomposites
(2008-08-01)
Liu, Yen-Yu
;
Liu, Tse-Ying
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Chen, San-Yuan
;
Liu, Dean-Mo
;
材料科學與工程學系
Porous SiO2/pHEMA biocomposites were synthesized in situ by incorporating silica nanoparticles with a hydroxyethyl methacrylate (HEMA) monomer, following a UV-induced photopolymerization. The nanostructure of the composites was characterized and the resulting physical properties were examined. The release kinetics of the model molecule-vitamin B12-and the hemocompatibility of the porous SiO2/pHEMA composites were investigated. Heterogeneous reaction kinetics is proposed to be the formation mechanism of the nanoporosity in the pHEMA matrix as a result of incorporating silica nanoparticles following photopolymerization. Experimental results also demonstrated that the incorporation of the silica nanoparticles into the pHEMA matrix not only enhanced the mechanical property but also maintained a good hemocompatibility of the resulting biocomposites. In addition, it was observed that the drug release profile of the composites (in the form of a membrane) can be precisely regulated from a two-stage pattern to one-stage pattern by varying the concentration of both the SiO2 nanoparticles and HEMA monomer during synthesis. The permeability of the model drug was enhanced by two orders of magnitude from 4.22 x10(-7) cm(2)/h to 3.92 x 10(-5) cm(2)/h by controlling the micro-to-nanostructure of the composites. The platelet adhesion experiment demonstrated low aggregation of the platelets on the surface of the biocomposite membranes, indicating a promising antithrombotic property.
Robust design for multiple dynamic quality characteristics using data envelopment analysis
(2008-08-01)
Tong, Lee-Ing
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Wang, Chun-Ho
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Tsai, Chih-Wei
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工業工程與管理學系
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Department of Industrial Engineering and Management
The Taguchi method is extensively adopted in various industries to continuously improve product design in response to customer requirements. The dynamic system of the Taguchi method is frequently implemented to design products with flexible applications. However, Taguchi v dynamic system can be employed only for individual quality characteristic, and the relationship between the quality characteristic and the signal factor is assumed to be linear. Because of these restrictions, Taguchi's dynamic system is ineffective for multiple quality characteristics or when the quality characteristic has a nonlinear relationship with the signal factor. This study describes a novel procedure for optimizing a dynamic system based on data envelopment analysis. The proposed procedure overcomes the limitations of Taguchi's dynamic system. Two cases are analyzed to demonstrate the effectiveness of the proposed procedure. The results show that the proposed procedure can enhance multiple dynamic quality characteristics. Copyright (C) 2008 John Wiley & Sons, Ltd.
介面系統、方法及裝置
(2008-08-01)
陳登吉
;
彭士榮
;
蔣加洛
本發明係揭露一種介面系統、方法及裝置,適用於一電子裝置,其包含一載入模組、一指令資料庫、一巨集模組、一物件模組、一指令輸入模組及一處理模組。載入模組用以載入一辨識裝置及一應用軟體;指令資料庫,包含複數個動作指令,任一動作指令皆對應應用軟體之一操作動作;巨集模組用以設定複數個巨集指令,以執行應用軟體之一組操作動作,其中任一巨集指令皆對應一組動作指令;物件模組用以將應用軟體之相對位置設定為操作動作控制之操作物件;指令輸入模組連結辨識裝置,用以輸入辨識裝置辨識一動作訊號所產生之一輸入指令;處理模組根據輸入指令,從指令資料庫中取得相對應之動作指令,並於載入之應用軟體中執行動作指令相對應之操作動作。
High light output intensity of titanium dioxide textured light-emitting diodes
(2008-08-01)
Huang, K. C.
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Lan, W. H.
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Huang, K. F.
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Lin, J. C.
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Cheng, Y. C.
Higher light output intensity and wider polar radiation pattern of InGaN/GaN multiple quantum well (MQW) light-emitting diodes (LEDs) with a different nanoscale titanium dioxide (TiO2) textured densities film have been observed. The light output power values and external quantum efficiency of the conventional LEDs at an injection current of 20 mA are 6.34 mW and 11.7%, respectively. The light output power values and external quantum efficiency of the nanoscaled TiO2 textured LEDs at an injection current of 20 mA are 7.55 mW and 14%, respectively. The light output intensity and power values of the nanoscaled TiO2 textured LEDs is approximately 65% and 20% higher than that of the conventional LEDs, respectively. (C) 2008 Elsevier Ltd. All rights reserved.
Document recommendation for knowledge sharing in personal folder environments
(2008-08-01)
Liu, Duen-Ren
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Lai, Chin-Hui
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Huang, Chiu-Wen
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資訊管理與財務金融系註：原資管所+財金所
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Department of Information Management and Finance
Sharing sustainable and valuable knowledge among knowledge workers is a fundamental aspect of knowledge management. In organizations, knowledge workers usually have personal folders in which they organize and store needed codified knowledge (textual documents) in categories. In such personal folder environments, providing knowledge workers with needed knowledge from other workers' folders is important because it increases the workers' productivity and the possibility of reusing and sharing knowledge. Conventional recommendation methods can be used to recommend relevant documents to workers; however, those methods recommend knowledge items without considering whether the items are assigned to the appropriate category in the target user's personal folders. In this paper, we propose novel document recommendation methods, including content-based filtering and categorization, collaborative filtering and categorization, and hybrid methods, which integrate text categorization techniques, to recommend documents to target worker's personalized categories. Our experiment results Show that the hybrid methods Outperform the pure content-based and the collaborative filtering and categorization methods. The proposed methods not only proactively notify knowledge workers about relevant documents held by their peers, but also facilitate push-mode knowledge sharing. (C) 2007 Elsevier Inc. All rights reserved.
Tight-binding theory for coupling asymmetric photonic crystal waveguides
(2008-08-01)
Huang, Chih-Hsien
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Hsieh, LVen-Feng
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Cheng, Szu-Cheng
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光電工程學系
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Department of Photonics
The physical properties of asymmetric photonic-crystal directional couplers are studied under the tight-binding model, which assumes that the field distribution of photon ic-cryst al waveguides is localized around periodic defects. The couplings of nearby defects between two asymmetric waveguides cause two dispersion relations to split further whereas the couplings of nearby defects within an individual waveguide cause the sinusoidal modulations of the dispersion curves. The field-envelope distributions of the coupler are expressed by using the eigenmodes of the tightbinding equations and are consistent with the comparing results from finite-difference time-domain simulations.
Lasing Behavior, Gain Property, and Strong Coupling Effects in GaN-Based Vertical-Cavity Surface-Emitting Lasers
(2008-08-01)
Lu, Tien-Chang
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Chu, Jung-Tang
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Chen, Shih-Wei
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Cheng, Bo-Siao
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Kuo, Hao-Chung
The optical properties of a GaN-based vertical-cavity surface-emitting laser (VCSEL) with two dielectric distributed Bragg reflectors were investigated under optically pumped operation. The laser emits blue-violet light at a wavelength of 414 nm at room temperature with a high spontaneous emission coupling factor (beta-factor) of 2 x 10(-2) and a linewidth of 0.25 nm. The optical gain was determined by the Hakki-Paoli method by measuring the photoluminescence spectra below threshold conditions. At room temperature, an optical gain of 2900 cm(-1) was obtained under threshold condition. The linewidth enhancement factor (alpha-factor) is estimated front the ratio of the wavelength and gain derivation with respect to the carrier density, and the alpha-factor at room temperature is estimated to be 2.8. Strong exciton-photon coupling in the microcavity was observed at room temperature. A 9 meV Rabi splitting with 60% peak-to-valley contrast was determined from the photoluminescence measurements. Emission spectra showing the evolution of anticrossing behavior were also observed.
內儲存無關項控制之階層式搜循線
(2008-08-01)
張書瑋
;
張銘宏
;
黃威
;
黃柏蒼
本發明提供一種內儲存無關項控制之階層式搜循線,其係在內容可定址記憶體中區分出複數區塊,每一區塊包含複數區域搜循線、一總體搜循線、一緩衝器及一記憶單元,將資料依照前置內容的長短依序儲存於區塊中,其中具有最長前置內容者儲存於最底部,並以其內無關項之狀態値做為緩衝器之控制訊號,控制總體搜循線尚之資料是否被傳遞到區域搜循線,而區域搜循線再將値傳送到記憶單元中。本發明無須複雜的控制電路及額外之儲存單元,且由於控制訊號係直接取自於無關項之狀態値,故可有效降低搜循線之功率消耗而不增加搜尋延遲時間。
晶粒控制及自我對準之複晶矽薄膜電晶體製造方法
(2008-08-01)
冉曉雯
;
周政偉
;
黃振昌
;
顏國錫
一種晶粒控制及自我對準之複晶矽薄膜電晶體製造方法,係利用儲熱島高熱容、低傳導係數的特性,延長矽晶粒的成長時間以及控制成核位置,並利用其不透光的性質,當作自我對準閘極之罩幕,節省額外的光罩費用,還可以抑制薄膜電晶體平面顯示器因背光源照射電晶體通道區所引起之光漏電效應;另外,閘極可作為自我對準離子佈植源/汲極之罩幕。因此能夠達到提高電晶體工作效能、縮短製程以及節省製造成本之效。
A quantum mechanics-based approach to model incident-induced dynamic driver behavior
(2008-08-01)
Sheu, Jiuh-Biing
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運輸與物流管理系註：原交通所+運管所
;
Department of Transportation and Logistics Management
A better understanding of the psychological factors influencing drivers, and the resulting driving behavior responding to incident-induced lane traffic phenomena while passing by an incident site is vital to the improvement of road safety. This paper presents a microscopic driver behavior model to explain the dynamics of the instantaneous driver decision process under lane-blocking incidents on adjacent lanes. The proposed conceptual framework decomposes the corresponding driver decision process into three sequential phases: (1) initial stimulus, (2) glancing-around car-following, and (3) incident-induced driving behavior. The theorem of quantum mechanics in optical flows is applied in the first phase to explain the motion-related perceptual phenomena while vehicles approach the incident site in adjacent lanes, followed by the incorporation of the effect of quantum optical flows in modeling the induced glancing-around car-following behavior in the second phase. Then, an incident-induced driving behavior model is formulated to reproduce the dynamics of driver behavior conducted in the process of passing by an incident site in the adjacent lanes. Numerical results of model tests using video-based incident data indicate the validity of the proposed traffic behavior model in analyzing the incident-induced lane traffic phenomena. It is also expected that such a proposed quantum-mechanics based methodology can throw more light if applied to driver psychology and response in anomalous traffic environments in order to improve road safety. (C) 2008 Elsevier B.V. All rights reserved.
M-theory superalgebra from multiple membranes
(2008-08-01)
Furuuchi, Kazuyuki
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Shih, Sheng-Yu Darren
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Takimi, Tomohisa
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電子物理學系
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Department of Electrophysics
We investigate space-time supersymmetry of the model of multiple M2-branes proposed by Bagger-Lambert and Gustavsson. When there is a central element in Lie 3-algebra, the model possesses an extra symmetry shifting the fermions in the central element. Together with the original worldvolume supersymmetry transformation, we construct major part of the eleven dimensional space-time super-Poincare algebra with central extensions. Implications to transverse five-branes in the matrix model for M-theory are also discussed.
Knowledge modeling in traditional Chinese medicine with fuzzy influence diagrams
(2008-08-01)
Kao, Han-Ying
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Huang, Chia-Hui
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Kao, Tai-Chi
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Kao, Han-Chung
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交大名義發表
Traditional Chinese medicine (TCM) has been developed for more than four thousand years. It is a complete medical system embracing diagnosis, treatment and prevention. However, the knowledge of TCM is linguistically vague and usually involves subjective judgments, which makes automated inference challenging. This study proposes a novel approach for knowledge modeling in TCM, fuzzy influence diagrams (FID). Considering the subjective knowledge as well as linguistic fuzziness in TCM, possibility distributions are used to model the uncertainty and causal relationships in influence diagrams, which extend the conventional influence diagrams into fuzzy influence diagrams. The FID provides a general platform for answering various queries in TCM, such as prognosis, diagnosis, and optimal treatment. The FID can bridge the qualitative fuzziness and quantitative numerical models in knowledge bases for TCM.
Cost-effective triple-mode reconfigurable pipeline FFT/IFFT/2-D DCT processor
(2008-08-01)
Lin, Chin-Teng
;
Yu, Yuan-Chu
;
Van, Lan-Da
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資訊工程學系
;
電機學院
This investigation proposes a novel radix-4(2) algorithm with the low computational complexity of a radix-16 algorithm but the lower hardware requirement of a radix-4 algorithm. The proposed pipeline radix-4(2) single delay feedback path (R4(2)SDF) architecture adopts a multiplierless radix-4 butterfly structure, based on the specific linear mapping of common factor algorithm (CFA), to support both 256-point fast Fourier transform/inverse fast Fourier transform (FFT/IFFT) and 8 x 8 2-D discrete cosine transform (DCT) modes following with the high efficient feedback shift registers architecture. The segment shift register (SSR) and overturn shift register (OSR) structure are adopted to minimize the register cost for the input re-ordering and post computation operations in the 8 x 8 2-D DCT mode, respectively. Moreover, the retrenched constant multiplier and eight-folded complex multiplier structures are adopted to decrease the multiplier cost and the coefficient ROM size with the complex conjugate symmetry rule and subexpression elimination technology. To further decrease the chip cost, a finite wordlength analysis is provided to indicate that the proposed architecture only requires a 13-bit internal wordlength to achieve 40-dB signal-to-noise ratio (SNR) performance in 256-point FFT/IFFT modes and high digital video (DV) compression quality in 8 x 8 2-D DCT mode. The comprehensive comparison results indicate that the proposed cost effective reconfigurable design has the smallest hardware requirement and largest hardware utilization among the tested architectures for the FFT/IFFT computation, and thus has the highest cost efficiency. The derivation and chip implementation results show that the proposed pipeline 256-point FFT/IFFT/2-D DCT triple-mode chip consumes 22.37 mW at 100 MHz at 1.2-V supply voltage in TSMC 0.13-mu m CMOS process, which is very appropriate for the RSoCs IP of next-generation handheld devices.
Preliminary analysis of the forces on the thoracic cage of patients with pectus excavatum after the Nuss procedure
(2008-08-01)
Chang, Pei Yeh
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Hsu, Zhen-Yu
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Chen, Da-Pan
;
Lai, Jin-Yao
;
Wang, Chao-Jan
Background. The Nuss procedure corrects pectus excavatum using a pre-bent bar that generates stress on the chest wall. To investigate the biomechanical effects after the Nuss procedure, we designed a three-dimensional finite element analysis model to analyze the distribution of stress and strain induced in the chest wall. Methods. Three patients with pectus excavatum aged 8, 7, and 7 years, were enrolled in this study. The greatest upward displacements of their sternums after the operation were measured from computed tomography images and chest X-ray films. Based on these displacements, we constructed three finite element analysis models for analyzing biomechanical changes in the thoracic cage after the Nuss procedure. Findings. The simulation results indicated that greatest strain occurred at the third through seventh cartilages, especially where they join the sternum and ribs. A high bilateral stress distribution was also found over the backs of the third to the seventh ribs near the vertebral column. Interpretation. The stress and strain induced by the Nuss procedure can be analyzed using our finite element analysis model. Although the stress and strain may have some influence on chest and spine development, a more detailed finite element analysis model is recommended for future study to improve the accuracy of our simulation results. (c) 2008 Elsevier Ltd. All rights reserved.
Integrating the Kano model into a robust design approach to enhance customer satisfaction with product design
(2008-08-01)
Chen, Chun-Chih
;
Chuang, Ming-Chuen
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應用藝術研究所
;
Institute of Applied Arts
The aesthetic qualities of products are critical factors in achieving higher customer satisfaction. This study presents a robust design approach incorporating the Kano model to obtain the optimal combination of design form elements. This can effectively enhance customer satisfaction and aesthetic product qualities with multiple-criteria characteristics. The Kano model is used to better understand the relationship between performance criteria and customer satisfaction, and to resolve trade-off dilemma in multiple-criteria optimization by identifying the key criteria in customer satisfaction. The robust design approach combines grey relational analysis with the Taguchi method to optimize subjective quality with multiple-criteria characteristics. This simultaneously yields the optimal aesthetic performance and reduces the variations in customer evaluations. Based on Kano model analysis, a weight adjustment process determines the weight of each product criterion for achieving the desired customer satisfaction performance. This process guides the prioritizing of multiple criteria, leading to higher customer satisfaction. A mobile phone design experiment was conducted to verify the benefits of using the proposed integrative approach. Results show that the generated optimal mobile phone design can effectively enhance overall aesthetic performance and customer satisfaction. Although mobile phone designs are the examples of this study, the proposed method may be further used as a universal robust design approach for enhancing customer satisfaction and product quality with multiple-criteria characteristics. (C) 2008 Elsevier B.V. All rights reserved.
Cross-scale electric manipulations of cells and droplets by frequency-modulated dielectrophoresis and electrowetting
(2008-08-01)
Fan, Shih-Kang
;
Huang, Po-Wen
;
Wang, Tsu-Te
;
Peng, Yu-Hao
;
材料科學與工程學系奈米科技碩博班
Two important electric forces, dielectrophoresis (DEP) and electrowetting-on-dielectric (EWOD), are demonstrated by dielectric-coated electrodes on a single chip to manipulate objects on different scales, which results in a dielectrophoretic concentrator in an EWOD-actuated droplet. By applying appropriate electric signals with different frequencies on identical electrodes, EWOD and DEP can be selectively generated on the proposed chip. At low frequencies, the applied voltage is consumed mostly in the dielectric layer and causes EWOD to pump liquid droplets on the millimetre scale. However, high frequency signals establish electric fields in the liquid and generate DEP forces to actuate cells or particles on the micrometre scale inside the droplet. For better performance of EWOD and DEP, square and strip electrodes are designed, respectively. Mammalian cells (Neuro-2a) and polystyrene beads are successfully actuated by a 2 MHz signal in a droplet by positive DEP and negative DEP, respectively. Droplet splitting is achieved by EWOD with a 1 kHz signal after moving cells or beads to one side of the droplet. Cell concentration, measured by a cell count chamber before and after experiments, increases 1.6 times from 8.6 x 10(5) cells ml(-1) to 1.4 x 10(6) cells ml(-1) with a single cycle of positive DEP attraction. By comparing the cutoff frequency of the voltage drop in the dielectric layer and the cross-over frequency of Re(f(CM)) of the suspended particles, we can estimate the frequency-modulated behaviors between EWOD, positive DEP, and negative DER A proposed weighted Re(f(CM)) facilitates analysis of the DEP phenomenon on dielectric-coated electrodes.