Browsing by Issue Date, starting with "2011-12-29"

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Single-axis-control-input gyroscope system having imperfection compensation
(2011-12-29)
CHEN Tsung-Lin
;
CHI Chien-Yu
;
LEE Chia-Wei
The present invention proposes a single-axis-control-input gyroscope system having imperfection compensation, which comprises a gyroscope and a state observer. The gyroscope includes a mechanical structure, and the dynamic behavior of the mechanical structure is described with a plurality of system parameters and a plurality of dynamic equations. The system parameters include a mass of the gyroscope, two main-axis spring constants, a cross-axis spring constant, two main-axis damping coefficients, a cross-axis damping coefficient and an angular velocity. The mechanical imperfections cause the system parameters to deviate from the designed values and become unknown values. The gyroscope receives a single-axis control signal and outputs a plurality of gyroscopic system dynamics. The single-axis control signal includes at least two frequency signals. The state observer is coupled to the gyroscope to receive the gyroscopic system dynamics as the inputs thereof to feed back compensations to the state observer. Thereby is estimated an angular velocity.
METHOD FOR GROWING GROUP III-V NITRIDE FILM AND STRUCTURE THEREOF
(2011-12-29)
Lee Wei I
;
Huang Hsin Hsiung
;
Chen Kuei Ming
;
Yeh Yen Hsien
A method for growing a Group III-V nitride film and a structure thereof are presented. The method is carried out by hydride vapor phase epitaxy (HVPE). The method includes the steps of, inter alia, slowly epitaxially growing a temperature ramping nitride layer on a substrate by rising a first growth temperature of 900-950° C. to a second growth temperature of 1000-1050° C. at a temperature-rising rate of 0.5-10° C./min. The lattice quality of the temperature ramping nitride layer is slowly transformed with the layer height, so that a stress induced by lattice mismatch between a sapphire substrate and a gallium nitride (GaN) layer is relieved.
Charge trapping induced frequency-dependence degradation in n-MOSFETs with high-k/metal gate stacks
(2011-12-30)
Dai, Chih-Hao
;
Chang, Ting-Chang
;
Chu, Ann-Kuo
;
Kuo, Yuan-Jui
;
Hung, Ya-Chi
This letter investigates the reliability issues of HfO(2)/Ti(1-x)N(x) metal-oxide-semiconductor field effect transistor in terms of static and dynamic stress. The results indicate threshold voltage (V(th)) instability under dynamic stress is more serious than that under static stress, owning to transient charge trapping within high-k dielectric. Capacitance-voltage techniques verified that electron trapping under dynamic stress was located in high-k dielectric near the source/drain (S/D) overlap region, rather than the overall dielectric. Furthermore, the V(th) shift clearly increases with an increase in dynamic stress operation frequency. This phenomenon can be attributed to the fact that electrons injecting to the S/D overlap region have insufficient time to de-trap from high-k dielectric. We further investigated the impact of different Ti(1-x)N(x) composition of metal-gate electrode on charge trapping characteristics, and observed that V(th) shift decreases significantly with an increase in the ratio of nitride. This is because the nitride atoms diffusing from the metal gate fill up oxygen vacancies and reduce the concentration of traps in high-k dielectric. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.
Resistive switching characteristics of ytterbium oxide thin film for nonvolatile memory application
(2011-12-30)
Tseng, Hsueh-Chih
;
Chang, Ting-Chang
;
Huang, Jheng-Jie
;
Chen, Yu-Ting
;
Yang, Po-Chun
This paper studies the effects of both the positive and negative forming processes on the resistive switching characteristics of a Pt/Yb(2)O(3)/TiN RRAM device. The polarity of the forming process can determine the transition mechanism, either bipolar or unipolar. Bipolar behavior exists after the positive forming process, while unipolar behavior exists after the negative forming process. Furthermore, the bipolar switching characteristics of the Pt/Yb(2)O(3)/TiN device can be affected by using a reverse polarity forming treatment, which not only reduces the set and reset voltage, but also improves the on/off ratio. Crown Copyright (C) 2011 Published by Elsevier B. V. All rights reserved.
Surface states related the bias stability of amorphous In-Ga-Zn-O thin film transistors under different ambient gasses
(2011-12-30)
Chen, Yu-Chun
;
Chang, Ting-Chang
;
Li, Hung-Wei
;
Chen, Shih-Cheng
;
Chung, Wan-Fang
This paper investigates the origin of the bias stability under ambient gas (oxygen, moisture and vacuum) of In-Ga-Zn-O thin film transistors with different annealing temperatures. In Zn-based TFTs, the electrical characteristic of device is a strongly function with the ambient gas, the simultaneous gas ambient and bias stresses are applied on devices annealed in atmosphere ambient to study this issue. The result shows the device which is annealed at temperature up to 330 degrees C has worst reliability. We suppose that the sensitivity of gas ambient depend the defect state, which is associated to the annealing temperature, of surface in a-IGZO. (C) 2011 Elsevier B.V. All rights reserved.
Role of environmental and annealing conditions on the passivation-free in-Ga-Zn-O TFT
(2011-12-30)
Fuh, Chur-Shyang
;
Sze, Simon Min
;
Liu, Po-Tsun
;
Teng, Li-Feng
;
Chou, Yi-Teh
We examined the characteristics of passivation-free amorphous In-Ga-Zn-O thin film transistor (a-IGZO TFT) devices under different thermal annealing atmospheres. With annealing at higher temperature, the device performed better at the above-threshold operation region, which indicated the film quality was improved with the decrease of defects in the a-IGZO active region. The mobility, threshold voltage and subthreshold swing of a-IGZO TFT annealed at 450 degrees C was 7.53 cm(2)/V s, 0.71 V and 0.18 V/decade, respectively. It was also observed that the a-IGZO was conductive after thermal annealing in the vacuum, due to the ease of oxygen out-diffusion from the a-IGZO back channel. The oxygen deficiency resultantly appeared, and provided leaky paths causing electrical unreliability when TFT was turned off. In contrast, the annealing atmosphere full of O(2) or N(2) would suppress the oxygen diffusion out of the a-IGZO back channel. The worst Vth degradation of a-IGZO TFT after positive gate bias stress and negative gate bias stress (NGBS) was about 2 V and -2 V, respectively. However, the V(th) shift in the NGBS testing could be suppressed to -0.5 V in vacuum chamber. Material analysis methods including X-ray photoelectron spectroscopy and scanning electron microscopy were used to investigate the change of a-IGZO film after different thermal annealing treatments. The variation of O 1s spectra with different annealing atmospheres showed the consistence with our proposed models. (C) 2011 Elsevier B.V. All rights reserved.
Paraffin wax passivation layer improvements in electrical characteristics of bottom gate amorphous indium-gallium-zinc oxide thin-film transistors
(2011-12-30)
Chang, Geng-Wei
;
Chang, Ting-Chang
;
Syu, Yong-En
;
Tsai, Tsung-Ming
;
Chang, Kuan-Chang
In this research, paraffin wax is employed as the passivation layer of the bottom gate amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs), and it is formed by sol-gel process in the atmosphere. The high yield and low cost passivation layer of sol-gel process technology has attracted much attention for current flat-panel-display manufacturing. Comparing with passivation-free a-IGZO TFTs, passivated devices exhibit a superior stability against positive gate bias stress in different ambient gas, demonstrating that paraffin wax shows gas-resisting characteristics for a-IGZO TFTs application. Furthermore, light-induced stretch-out phenomenon for paraffin wax passivated device is suppressed. This superior stability of the passivated device was attributed to the reduced total density of states (DOS) including the interfacial and semiconductor bulk trap densities. (C) 2011 Elsevier B.V. All rights reserved.
Real-Time Vehicle Detector with Dynamic Segmentation and Rule-based Tracking Reasoning for Complex Traffic Conditions
(2011-12-31)
Wu, Bing-Fei
;
Juang, Jhy-Hong
;
電機工程學系
;
Department of Electrical and Computer Engineering
Vision-based vehicle detector systems are becoming increasingly important in ITS applications. Real-time operation, robustness, precision, accurate estimation of traffic parameters, and ease of setup are important features to be considered in developing such systems. Further, accurate vehicle detection is difficult in varied complex traffic environments. These environments include changes in weather as well as challenging traffic conditions, such as shadow effects and jams. To meet real-time requirements, the proposed system first applies a color background to extract moving objects, which are then tracked by considering their relative distances and directions. To achieve robustness and precision, the color background is regularly updated by the proposed algorithm to overcome luminance variations. This paper also proposes a scheme of feedback compensation to resolve background convergence errors, which occur when vehicles temporarily park on the roadside while the background image is being converged. Next, vehicle occlusion is resolved using the proposed prior split approach and through reasoning for rule-based tracking. This approach can automatically detect straight lanes. Following this step, trajectories are applied to derive traffic parameters; finally, to facilitate easy setup, we propose a means to automate the setting of the system parameters. Experimental results show that the system can operate well under various complex traffic conditions in real time.
Traffic-based DRX Cycles Adjustment Scheme for 3GPP LTE Systems
(2012)
Yu, Yu-Ping
;
Feng, Kai-Ten
;
電機工程學系
;
Department of Electrical and Computer Engineering
The 3GPP long term evolution (LTE) standard is developed to enhance mobile services from the former 3G systems. In order to prolong the battery life of mobile device, a novel discontinuous reception (DRX) scheme is specified in the standard to reduce the power consumption of a user equipment. In this paper, a traffic-based DRX cycles adjustment (TDCA) scheme is proposed to enhance the energy saving performance based on existing DRX operation. A partially observable Markov decision process (POMDP) is employed to conjecture the present traffic status. Optimal policy for the selection of DRX parameters can be obtained via the POMDP framework in the proposed TDCA scheme. Simulation results show that the TDCA scheme can enhance the energy saving efficiency while the quality-of-service constraint is still satisfied.
歐盟氣候變遷政策的規範、策略與實踐
(2012)
洪德欽
;
Horng, Der-chin
;
科技法律研究所
;
Institute of Technology Law
Safety Management in a Relationship-Oriented Culture
(2012)
Hsu, Shang Hwa
;
Lee, Chun-Chia
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
A relationship-oriented culture predominates in the Greater China region, where it is more important than in Western countries. Some characteristics of this culture influence strongly the organizational structure and interactions among members in an organization. This study aimed to explore the possible influence of relationships on safety management in relationship-oriented cultures. We hypothesized that organizational factors (management involvement and harmonious relationships) within a relationship-oriented culture would influence supervisory work (ongoing monitoring and task instructions), the reporting system (selective reporting), and teamwork (team communication and co-ordination) in safety management at a group level, which would in turn influence individual reliance complacency, risk awareness, and practices. We distributed a safety climate questionnaire to the employees of Taiwanese high-risk industries. The results of structural equation modeling supported the hypothesis. This article also discusses the findings and implications for safety improvement in countries with a relationship-oriented culture.
大學生直銷面面觀
(2012-01-01)
顏伊婷
;
Department of Communication and Technology
;
傳播與科技學系
直銷業走入校園早已不是新鮮事，近年更是愈來愈多大學生成為「多層次傳銷」事業下的生力軍。對經營直銷的大學生而言，究竟又是什麼因素吸引他們加入直銷的行列呢？
赴美免簽　省錢又省時
(2012-01-01)
蘇冠心
;
Department of Communication and Technology
;
傳播與科技學系
美國在台協會（AIT）在2011年12月22日宣布將台灣納入免簽證計畫候選國，預估明年下半年可正式獲得免美簽，未來國人赴美不再需要繁複的簽證申請程序，省錢又省時。
High throughput concurrent lookahead adaptive decision feedback equaliser
(2012-01-01)
Lin, Y. -C.
;
Jou, S. -J.
;
Shiue, M. -T.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
A time-domain adaptive decision feedback equaliser (ADFE) for multi-gigabit wire-line 2-pulse amplitude modulation (PAM) communication systems is proposed. The throughput rate of a conventional ADFE is limited by the loops in the circuit. This investigation develops two methods for breaking or virtually breaking these loops. The first is the method of batch mode coefficient updating (BMCU), and the second is the concurrent lookahead (CLA) method. Since the loops are broken or virtually broken, a pipeline and/or a parallel method can be applied to design a throughput-rate-unlimited ADFE. The results of a simulation of the 10GBASE-S system reveal that the proposed BMCU-based CLA ADFE has the same average signal-to-noise ratio (SNR) as the original sequential ADFE for multi-mode fibres of length 30-90 m.
高負載驅動裝置
(2012-01-01)
莊景德
;
盧建宇
本發明係揭露一種高負載驅動裝置，包含一反向器，用來接收一數位電壓，並將其反向後輸出，此反向器之輸出端連接一電容、一第一、第二P型場效電晶體、一第一、第三N型場效電晶體，且上述電晶體與一第二N型場效電晶體係組成一推動電路，以與一推動P型場效電晶體連接，負載透過推動P型場效電晶體連接一高電壓。當數位電壓從低準位提升至高準位時，推動電路利用電容之原來電壓降，將推動P型場效電晶體之閘極電壓控制在比接地電壓更低之低穩定電壓，以快速驅動負載。本發明可提升對於高負載的切換速度，並降低延遲時間及提升效能。
異質雙群組之效用規模分析
(2012)
謝國文
;
Shieh Gwowen
;
國立交通大學管理科學系（所）
期刊論文發表準則強調在實證資料分析中，應使用效果規模和其區間估計進行重要數據的討論，為了增進社會科學理論和實務發展，本研究探討雙群組之標準化平均差的區間估計法，目的在於改進現有方法在理論和計算兩方面的複雜性，提供具備簡明原理和運算的信賴區間。由於事先規劃研究設計需要，同時也考慮符合精確度要求的樣本數計算法，而精確度可分為期望區間寬度和區間寬度涵蓋率。
Capacity Results of an Optical Intensity Channel With Input-Dependent Gaussian Noise
(2012-01-01)
Moser, Stefan M.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper investigates a channel model describing optical communication based on intensity modulation. It is assumed that the main distortion is caused by additive Gaussian noise, however, with a noise variance depending on the current signal strength. Both the high-power and low-power asymptotic capacities under simultaneously both a peak-power and an average-power constraint are derived. The high-power results are based on a new firm (nonasymptotic) lower bound and a new asymptotic upper bound. The upper bound relies on a dual expression for channel capacity and the notion of capacity-achieving input distributions that escape to infinity. The lower bound is based on a new lower bound on the differential entropy of the channel output in terms of the differential entropy of the channel input. The low-power results make use of a theorem by Prelov and van der Meulen.
E-LEARNING - BEST PRACTICE IN PHOTOGRAMMETRY, REMOTE SENSING AND GIS - STATUS AND CHALLENGES
(2012-01-01)
Koenig, Gerhard
;
Shih, Peter T. Y.
;
Katterfeld, Christiane
;
土木工程學系
;
Department of Civil Engineering
In addition to professional training, computer aided teaching has long tradition. The difficult economic situation, however, forced many customers to take drastic austerity measures in the field of learning. Cost pressure encouraged a new openness to innovative and tailored learning concepts. As a result e-learning gained more interest and importance promising great benefit to the user. Around the world a variety of well-designed e-learning products exist. The web pages of Commission VI/2 (http://www.igg.tuberlin.de/ISPRS/) provide a decision aid to locate relevant material. Links to websites known to the authors are listed; a search function allows selective access, taking account of quality criteria. This article describes best practice e-learning applications in photogrammetry, remote sensing and GIS. The rating is based on results of the Computer Assisted Teaching CONtest (CATCON) initiated by ISPRS, and on observation of recent developments.
Using SEM to Analyze Complex Survey Data: A Comparison between Design-Based Single-Level and Model-Based Multilevel Approaches
(2012)
Wu, Jiun-Yu
;
Kwok, Oi-man
;
教育研究所
;
Institute of Education
Both ad-hoc robust sandwich standard error estimators (design-based approach) and multilevel analysis (model-based approach) are commonly used for analyzing complex survey data with nonindependent observations. Although these 2 approaches perform equally well on analyzing complex survey data with equal between-and within-level model structures (B. O. Muthen & Satorra, 1995), the performances of these 2 approaches for analyzing multilevel data with unequal between-and within-level structures have not yet been systematically examined. In this study, we extended B. O. Muthen and Satorra's (1995) study by comparing these 2 approaches and an additional model-based maximum model for analyzing multilevel data considering number of clusters, cluster size, intraclass correlation, and the equality of different level structures. The simulation results showed the model-based maximum model generally performed well across conditions. This model is also recommended as an alternative for analyzing nonindependent survey data, especially when the information of the higher level model structure is not known.
軍用射頻關鍵元組件技術研究
(2012)
張翼
;
CHANG EDWARD YI
;
國立交通大學材料科學與工程學系（所）
本計劃之主要研究為發展「主動相位陣列雷達」所需之高頻、高功率、高線性度及高效率的氮化鎵(GaN)高電子遷移率電晶體，首先將磊晶技術、元件製程、及散熱封裝等方向做整合性研發，以建立完整且系統化之氮化鎵射頻高功率元件之關鍵技術。研究方法為首先以有機金屬氣相沉積設備(MOCVD)磊晶技術，在具高熱傳特性之碳化矽基板(SiC)上磊晶三族氮化物，並研發出調控碳化矽基板與磊晶三族氮化物間晶格不匹配(lattice mismatch)與熱膨脹系數匹配等問題，成長符合軍用射頻之高輸出功率密度放大器之磊晶結構，預期目標可達到電子遷移率大於1800 cm2/Vs及載子密度達1×1013cm-2。接著開發先進之氮化鎵高載子遷移率電晶體(HEMT)製程技術，結合背晶貫孔技術之開發，製作出穩定高性能之GaN HEMT高功率元件，並佐以DC及RF量測系統做元件之分析驗證，預期在X-band下操作，元件之功率密度可達5W/mm。此外亦將進行氮化鎵之HEMT高功率密度輸出元件其散熱封裝之模擬與設計，開發高散熱性氮化鎵/氮化鋁鎵HEMT on SiC高電子遷移率射頻功率元件製程技術。