Browsing by Issue Date, starting with "2011-12-01"

Now showing 1 - 20 of 39760

The Implementation of a Low-Power Biomedical Signal Processor for Real-Time Epileptic Seizure Detection on Absence Animal Models
(2011-12-01)
Chen, Tsan-Jieh
;
Chiueh, Herming
;
Liang, Sheng-Fu
;
Chang, Shun-Ting
;
Jeng, Chi
Epilepsy is one of the most common neurological disorders, with a worldwide prevalence of approximately 1%. A considerable portion of epilepsy patients cannot be treated sufficiently by today's available therapies. Implantable closed-loop neurostimulation is an innovative and effective method for seizure control. A real-time seizure detector is the kernel of a closed-loop seizure controller. In this paper, a low-power biomedical signal processor based on reduced instruction set computer (RISC) architecture for real-time seizure detection is implemented to achieve low-power consumption and perform continuous and real-time processing. The low-power processor is implemented in a 0.18 mu m complementary-metal-oxide semiconductor technology to verify functionality and capability. The measurement results show the implemented processor can reduce over 90% power consumption compared with our previous prototype, which was implemented on an enhanced 8051 microprocessor. This seizure detector was applied to the continuous EEG signals of four Long-Evans rats with spontaneous absence seizures. It also processed 24 h long-term and uninterrupted EEG sequence. The developed seizure detector can be applied for online seizure monitoring and integrated with an electrical stimulator to perform a closed-loop seizure controller in the future.
Enhanced Temperature Dependence of Phonon-Scattering-Limited Mobility in Compressively Uniaxial Strained pMOSFETs
(2011-12-01)
Chen, William Po-Nien
;
Kuo, Jack Jyun-Yan
;
Su, Pin
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper investigates the temperature dependence of phonon-scattering-limited mobility mu(PH) for advanced short-channel strained pMOS devices. By using the split CV method and Matthiessen's rule, surface-roughness-limited mobility mu SR and mu(PH) are successfully decoupled. This paper indicates that the temperature sensitivity of mu(PH) is proportional to T(-1.75) for a neutral stressor and becomes higher when compressive strain is applied. It is explained by the higher optical phonon energy induced by uniaxially compressive strain. Our new findings may also explain the previously reported higher temperature sensitivity of drain current present in uniaxial strained pMOSFETs.
An Analytic Hierarchy Process-Based Risk Assessment Method for Wireless Networks
(2011-12-01)
Tsai, Hsin-Yi
;
Huang, Yu-Lun
;
電控工程研究所
;
Institute of Electrical and Control Engineering
This paper presents a wireless risk assessment method to help an administrator manage wireless network security. The assessment method consists of a risk model and an assessment measure. The risk model is in charge of modeling the wireless network risk. Security requirements, wireless attacks, and system configurations are considered in the model. The assessment measure is an algorithm which determines the risk value of the wireless network according to the risk model. Our risk model is developed upon an extended analytic hierarchy process, which contains the 4 layers: the risk layer, the requirement layer, the attack layer, and the configuration layer. The separate layers of the risk model are helpful in dealing with the dynamics of a wireless network because only the related layers are introduced to the assessment measure when changes of the network are detected. Based on the risk model per device, our assessment measure evaluates the wireless network risk in consideration of the relations between devices, attacks, and configurations. Hence, our risk assessment method, composed of the risk model and the assessment measure, can determine the wireless network risk efficiently while considering the dependencies in the wireless network. Two examples are introduced in this paper to examine the feasibility of our method. In the first example, we demonstrate that the risk values derived by our method meet the ground truth by performing practical experiments. The second example shows that our method can evaluate the risk of a changing wireless network with efficiency, and can distinguish disparities in different wireless networks.
Investigation statistics of bipolar multilevel memristive mechanism and characterizations in a thin FeO(x) transition layer of TiN/SiO(2)/FeO(x)/Fe structure (vol 110, 053703, 2011)
(2011-12-01)
Chang, Yao-Feng
;
Chang, Ting-Chang
;
Chang, Chun-Yen
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Chaos control of new Mathieu-van der Pol systems by fuzzy logic constant controllers
(2011-12-01)
Li, Shih-Yu
;
機械工程學系
;
Department of Mechanical Engineering
In this paper, a new fuzzy logic controller-fuzzy logic constant controller (FLCC) is introduced to chaotic signals controlling. The main ideas of the FLCC are described as follows: (1) proving the two chaotic systems are going to achieve asymptotically stable via Lyapunov direct method; (2) via detecting the sign of the errors, the appropriate fuzzy logic control scheme is operated; (3) choosing the upper bound and the lower bound of the error derivatives of the chaotic signals to be the consequent parts (corresponding controllers). Due to controllers in traditional method - derived by Lyapunov direct method, are always complicated, nonlinear form or the functions of errors, a new simplest controller-FLCC is presented in this paper to synchronize two chaotic signals. Through the FLCC, there are three main contributions can be obtained: (1) the mathematical models of the nonlinear chaotic systems can be unknown, all we have to do is capturing the signals of the unknown systems; (2) through the fuzzy logic rules, the strength of controllers can be adjusted via the corresponding membership functions (which are decided by the values of error derivatives); (3) by the FLCC, the chaotic system can be much more exactly and efficiently controlled to the trajectory of our goal than traditional ones. Three cases, original point, regular function and chaotic Qi system (with large values of initial conditions), are given to illustrate the effectiveness of our new FLC. (C) 2011 Elsevier B.V. All rights reserved.
Focus plus Context Metro Maps
(2011-12-01)
Wang, Yu-Shuen
;
Chi, Ming-Te
;
交大名義發表
;
National Chiao Tung University
We introduce a focus+context method to visualize a complicated metro map of a modern city on a small displaying area. The context of our work is with regard the popularity of mobile devices. The best route to the destination, which can be obtained from the arrival time of trains, is highlighted. The stations on the route enjoy larger spaces, whereas the other stations are rendered smaller and closer to fit the whole map into a screen. To simplify the navigation and route planning for visitors, we formulate various map characteristics such as octilinear transportation lines and regular station distances into energy terms. We then solve for the optimal layout in a least squares sense. In addition, we label the names of stations that are on the route of a passenger according to human preferences, occlusions, and consistencies of label positions using the graph cuts method. Our system achieves real-time performance by being able to report instant information because of the carefully designed energy terms. We apply our method to layout a number of metro maps and show the results and timing statistics to demonstrate the feasibility of our technique.
Design of Compact Linear Electromagnetic Actuator for Auto-Focusing in Phone Camera
(2011-12-01)
Lai, L. K.
;
Tsai, C. L.
;
Liu, T. S.
;
機械工程學系
;
Department of Mechanical Engineering
This paper proposes a novel linear electromagnetic actuator (LEA) for auto-focusing of compact phone cameras. An LEA consists of permanent magnets, iron cores, and coils, which are all magnetic circuit components. When coils are powered, induced magnetic field generates N and S poles around iron cores. Thus, unlike voice coil motors (VCMs) that employ the Lorentz force, the motion of the moving part in this study is arisen from a property-same poles repel each other while opposite poles attract each other. When compared to conventional VCM actuators in simulation results, the proposed LEA generates larger force, whereas using smaller current.
Investigation statistics of bipolar multilevel memristive mechanism and characterizations in a thin FeOx transition layer of TiN/SiO2/FeOx/Fe structure (vol 110, 053703, 2011)
(2011-12-01)
Chang, Yao-Feng
;
Chang, Ting-Chang
;
Chang, Chun-Yen
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Capability Assessment for Processes with Multiple Characteristics: A Generalization of the Popular Index C(pk)
(2011-12-01)
Pearn, W. L.
;
Shiau, J. -J. H.
;
Tai, Y. T.
;
Li, M. Y.
;
統計學研究所
Process capability index C(pk) is the most popular capability index widely used in the manufacturing industry. Existing research on the yield-based measure index C(pk) to date is restricted to processes with single characteristics. However, many manufacturing processes are commonly described with multiple characteristics, for example, the gold bumping process in the TFT-LCD (thin film transistor-liquid crystal display) manufacturing industry. In the gold bumping process, gold bumps have multiple characteristics all having effects on the process yield. Obtaining accurate gold bumping manufacturing yield is very important for quality assurance and in providing guidance toward process improvement. To obtain accurate yield assessment for processes with multiple characteristics, we propose a new overall yield-measure index C(pk)(T), which is a generalization of the index C(pk), and a natural estimator (C) over cap (T)(pk) of C(pk)(T). For the purpose of making inferences on the process capability, we derive a quite accurate approximation of the distribution of (C) over cap (T)(pk) since the distribution is analytically intractable. With this distribution, we tabulate the lower confidence bounds of the new index under various sample sizes for in-plant applications. In addition, we construct a statistical test on the new yield-measure index in order to examine whether the yield meets the customers' requirements. For illustration purpose, a real case in a gold bumping factory located in the Science-based Industrial Park at Hsinchu, Taiwan is presented. Copyright (C) 2011 John Wiley & Sons, Ltd.
放大器非線性失真之幕後校正方法及系統
(2011-12-01)
范振麟
;
吳介琮
本發明是關於一種放大器非線性失真之幕後校正方法及系統。主要是藉由將大小不同之亂數訊號在進入放大器前分別以個別或一起混入的方式混入輸入訊號之中，讓這些亂數訊號與輸入訊號一起經由放大器放大，並且由後級的類比數位轉換器加以量化成數位輸出訊號。再來將該數位輸出訊號經由非線性補償電路線性化以產出一個線性化輸出訊號，接著將該線性化輸出訊號與後級的類比數位轉換器的數位輸出訊號經參數萃取器將校正參數萃取出來。最後利用非線性係數偵測器把校正參數之非線性係數計算出來，將該非線性係數輸出給非線性補償電路以進行非線性補償並達到放大器非線性失真之幕後校正。其中非線性係數偵測器是由累加器、加法器與減法器所組成，此偵測器利用注入的亂數序列之值將非線性失真係數加以計算出來。
Investigation of the Galvanic Effect between RuN Barriers and Cu Seed Layers
(2011-12-01)
Wu, Chia-Yang
;
Lee, Wen-Hsi
;
Chang, Shih-Chieh
;
Wang, Ying-Lang
;
照明與能源光電研究所
In this study, we investigated the galvanic effect between the Cu metals and ruthenium nitride (RuNx) films that were deposited at various nitrogen (N-2) gas flow rates in chemical mechanical polishing slurries. It was found that the galvanic corrosion of the RuNx films was inhibited with increasing N-2 gas flow ratio, whereas the galvanic corrosion of the Cu seed layers was enhanced. Electrochemical impedance spectroscopy showed that the galvanic corrosion resistance of RuNx increased and that of the ruthenium oxide layer decreased as N-2 flow ratio increased. This was because the increase in the N content in the RuNx films inhibited the corrosion and oxidation of the Ru metals. (C) 2011 The Japan Society of Applied Physics
Energy Harvesting Electronics for Vibratory Devices in Self-Powered Sensors
(2011-12-01)
Chao, Paul C. -P.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Recent advances in energy harvesting have been intensified due to urgent needs of portable, wireless electronics with extensive life span. The idea of energy harvesting is applicable to sensors that are placed and operated on some entities for a long time, or embedded into structures or human bodies, in which it is troublesome or detrimental to replace the sensor module batteries. Such sensors are commonly called "self-powered sensors." The energy harvester devices are capable of capturing environmental energy and supplanting the battery in a standalone module, or working along with the battery to extend substantially its life. Vibration is considered one of the most high power and efficient among other ambient energy sources, such as solar energy and temperature difference. Piezoelectric and electromagnetic devices are mostly used to convert vibration to ac electric power. For vibratory harvesting, a delicately designed power conditioning circuit is required to store as much as possible of the device-output power into a battery. The design for this power conditioning needs to be consistent with the electric characteristics of the device and battery to achieve maximum power transfer and efficiency. This study offers an overview on various power conditioning electronic circuits designed for vibratory harvester devices and their applications to self-powered sensors. Comparative comments are provided in terms of circuit topology differences, conversion efficiencies and applicability to a sensor module.
【陽明人】註腳二十九
(國立陽明大學牙醫校友會, 2011-12)
萬曉晴
Heterotic E-6 GUTs and partition functions
(2011-12-01)
Ito, Motoharu
;
Kuwakino, Shogo
;
Maekawa, Nobuhiro
;
Moriyama, Sanefumi
;
Takahashi, Keijiro
The E-6 grand unified theory is an attractive candidate intermediate theory between the standard model and string theory. However, only one E-6 grand unified model with three generations and at least one adjoint Higgs field has been derived from string theory in the literature, and this model is phenomenologically unsatisfactory. Recently, in arXiv:1012.1690, we have constructed two new such E-6 grand unified models in heterotic asymmetric orbifolds. Although our new models themselves cannot resolve the unsatisfactory point in the previous model, our discovery raises hopes that one can construct many other such models in this framework and find better models. Here, by giving partition functions explicitly, we explain the details of our construction. Utilizing the lattice engineering technique and the diagonal embedding method, we can construct models systematically. We hope that these techniques and the details of our construction will lead to more phenomenologically desirable models.
A Compact Filtering 180 degrees Hybrid
(2011-12-01)
Lin, Chin-Kai
;
Chung, Shyh-Jong
;
傳播研究所
;
Institute of Communication Studies
A novel compact filtering 180 hybrid utilizing coupled resonators is presented. The equivalent-circuit structure is just like a bandpass filter, thus the frequency response is filter-like. The sum and difference port operations respectively correspond to the symmetric and antisymmetric states; therefore, isolation between sum and difference ports is accomplished by geometrical symmetry. The synthesis method of the filtering 180 hybrid is illustrated. The proposed structure is decomposed into one power divider and one balun, which are designed separately. A second-order filtering 180 hybrid prototype centered at 2.4 GHz with 0.2-dB Chebyshev equal-ripple response and 10% fractional bandwidth is demonstrated. The passband insertion loss is about (3.0 + 0.7) dB, and the isolation between the sum and difference port is greater than 20 dB. Magnitude imbalance is less than 1 dB and phase imbalance is within 2 degrees. Good agreement between simulation and experimental results is achieved.
Eco-Displays: The Color LCD's Without Color Filters and Polarizers
(2011-12-01)
Huang, Yi-Pai
;
Lin, Fang-Cheng
;
Shieh, Han-Ping D.
;
光電工程學系
;
顯示科技研究所
The higher and higher power consumption of LCD-TVs is accompanied by an increase in panel size. By eliminating two of the most power hungry optical components: color filters and polarizers, the stencil-field-sequential-color (Stencil-FSC) with RGBW-LED backlight is applied to LCDs with 120-240 Hz field rates to not only efficiently suppress color breakup but also yield an ultra-low average power consumption. The optical power consumption can be reduced to 13% compared to that of current FSC-LCDs. As a result, a 42-in LCD-TV may only require 9 W optical power consumption.
AN EFFICIENT APPROACH TO SOLVING THE MINIMUM SUDOKU PROBLEM
(2011-12-01)
Lin, Hung-Hsuan
;
Wu, I-Chen
;
資訊工程學系
;
Department of Computer Science
Since Sudoku was invented, it has been an open problem to find the minimum-clue Sudoku puzzles, also commonly called the minimum Sudoku problem. Solving the problem can be done by checking 5,472,730,538 essentially different Sudoku grids independently or in parallel. In the past, the program CHECKER, written by McGuire, required about 311 thousand years on one-core CPU to check these grids completely, according to our experimental analysis. This paper is to propose a more efficient approach to solving this problem. We design a new algorithm, named disjoint minimal unavoidable set (DMUS) algorithm, to help solve the minimum Sudoku problem more efficiently. After incorporating the algorithm into the program and further tuning the program code, our experiments showed that the performance was greatly improved by a factor of 128.67. Hence, it is estimated that it only takes about 2417 years to solve the problem. Thus, it becomes feasible and optimistic to solve this problem by using a volunteer computing system, such as BOINC.(2,3)
【陽明大事記】2011北市新北市聯合尾牙報導
(國立陽明大學牙醫校友會, 2011-12)
楊文甫
;
林世明
Nonpolar light emitting diode made by m-plane n-ZnO/p-GaN heterostructure
(2011-12-01)
Chen, C. W.
;
Hung, S. C.
;
Lee, C. H.
;
Tun, C. J.
;
Kuo, C. H.
Nonpolar (100) m-plane n-ZnO/p-GaN light-emitting-diodes (LEDs) were grown by chemical vapor deposition on p-GaN templates which was grown by metalorganic chemical vapor deposition on LiAlO(2)(100) substrate. Direct current (DC) electroluminescence (EL) measurements yielded a peak at 458nm. The EL peak position was independent of drive current and a full width of half maximum (FWHM) of 21.8 nm was realized at 20mA. The current-voltage characteristics of these diodes showed a forward voltage (V(f)) of 6V with a series resistance of 2.2 x 10(5) Omega. (C) 2011 Optical Society of America
電流式雙斜率溫度數位轉換裝置
(2011-12-01)
林明澤
;
洪崇智
本發明係揭露一種電流式雙斜率溫度數位轉換裝置，包含一溫度相依電流源與一參考電流源，首先，溫度相依電流源對一電容充電，接著參考電流源對電容進行放電，電容係連接至少一觸發器，觸發器根據電容之端電壓輸出一第一數位訊號至一邏輯控制器中，邏輯控制器再根據第一數位訊號，輸出一第二數位訊號至一時間至數位轉換器中，轉換器在參考電流對電容放電時，且第一數位訊號變動前，接收第二數位訊號與一時脈訊號，以產生對應之數位輸出值。本發明利用雙斜率架構達成高線性解析度的要求，以避免一般時域電路所產生的曲率效應。