Browsing by Issue Date, starting with "2009-03-01"

Now showing 1 - 20 of 51386

Mining decision rules on data streams in the presence of concept drifts
(2009-03-01)
Tsai, Cheng-Jung
;
Lee, Chien-I.
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Yang, Wei-Pang
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資訊工程學系
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Department of Computer Science
In a database, the concept of all example might change along with time, which is known as concept drift. When the concept drift occurs, the classification model built by using the old dataset is not suitable for predicting a new dataset. Therefore, the problem of concept drift has attracted a lot of attention in recent years. Although many algorithms have been proposed to solve this problem, they have not been able to provide users with a satisfactory solution to concept drift. That is, the current research about concept drift focuses only on updating the classification model. However, real life decision makers might be very interested in the rules of concept drift. For example, doctors desire to know the root causes behind variation in the causes and development of disease. In this paper, we propose a concept drift rule mining tree, called CDR-Tree, to accurately discover the underlying rule governing concept drift. The main contributions of this paper are: (a) we address the problem of mining concept-drifting rules which has not been considered in previously developed classification schemes; (b) we develop a method that call accurately mine rules governing concept drift: (c) we develop a method that should classification models be required, call efficiently and accurately generate such models via a simple extraction procedure rather than constructing them anew; and (d) we propose two strategies to reduce the complexity of concept-drifting, rules mined by our CDR-Tree. (C) 2007 Elsevier Ltd. All rights reserved.
Full-field measurement of the phase retardation for birefringent elements by using common path heterodyne interferometry
(2009-03-01)
Chen, Yen-Liang
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Su, Der-Chin
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光電工程學系
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Department of Photonics
A collimated heterodyne light passes through the tested material and an analyzer, full-field interference signals are taken by a fast CMOS camera. The series of interference intensities recorded at any pixel are the sampling points of a sinusoidal signal. From those points, the associated argument of that pixel can be derived by a least-square sine fitting algorithm on IEEE 1241 Standards. Subtracting the average argument of the reference signal, the phase retardation of that pixel can be obtained. The phase retardations of other pixels can be obtained similarly. Its validity is demonstrated. (C) 2008 Elsevier Ltd. All rights reserved
A FAST MULTISPRITE GENERATOR WITH NEAR-OPTIMUM CODING BIT-RATE
(2009-03-01)
Kuo, I-Sheng
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Chen, Ling-Hwei
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資訊工程學系
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Department of Computer Science
Sprite coding, which can increase the coding efficiency of backgrounds greatly, is a novel technology adopted in MPEG-4 object-based coding. Due to the geometric transformation applied to each nonreference frame in the procedure of sprite coding, the generated sprite is distorted and the available view angles relative to the reference frame are restricted. These problems can be resolved by using multiple sprites. An optimal multisprite generator has been proposed by Farin et al., but the optimal method requires high computation in the sprite coding cost. To treat this disadvantage, a fast multisprite partition algorithm is proposed in this paper based on frame translations and scalings. The proposed algorithm divides a video sequence into several subsequences, and a sprite is generated from each subsequence. The experimental results show that the executing speed of the proposed method is increased by 10 to 190 times than the optimal method, with the total size of generated sprites is slightly higher and the qualities of generated sprites are preserved.
Threshold-Voltage Fluctuation of Double-Gated Poly-Si Nanowire Field-Effect Transistor
(2009-03-01)
Hsu, Hsing-Hui
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Lin, Horng-Chih
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Chan, Leng
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Huang, Tiao-Yuan
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電子工程學系及電子研究所
In this letter, the fluctuation characteristics of polycrystalline silicon (poly-Si) nanowire (NW) thin-film transistors (TFTs) with independently controlled double-gate configuration were studied. The defects existing in the NW channels are identified as one of the major sources for the fluctuation. The passivation of these defects by plasma treatment is shown to be effective for reducing the fluctuation. We have also found that the fluctuation is closely related to the operation modes. When only one of the gates is employed as the driving gate to control the switching behavior of the device, an optimum bias for the other gate can be found for minimizing the fluctuation.
Variation Analysis of Sphygmogram to Assess Cardiovascular System under Meditation
(2009-03-01)
Liu, Chuan-Yi
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Wei, Ching-Chuan
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Lo, Pei-Chen
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電控工程研究所
;
電信工程研究所
In this article, we studied how meditation affects the characteristics of the cardiovascular system, mainly based on blood pressure waveforms (BPW). Four parameters derived from BPW include the rising slope (h(1)/t(1)), normalized height of T wave (h(3)/h(1)), normalized height of V(3) valley (h(4)/h(1)) and normalized height of D wave (h(5)/h(1)), where t(1) and h(i), i 1, ,5 are quantitative features of the BPW waveform pattern. A larger value of h(1)/t(1) reflects better heart ejection ability and aorta compliance. A larger value of h(3)/h(1) may infer an arterial system with good elasticity. The decrease (increase) of h(4)/h(1) parameter indicates the decrease (increase) of peripheral resistance of vessels. A larger value of h(5)/h(1) indicates better artery elasticity and aortic valve function. In comparison with the control group, Zen-meditation practitioners have more after-meditation h(1)/t(1), h(3)/h(1) and h(5)/h(1) increase, with more h(4)/h(1) decrease, with statistical significance (P 0.05). The observation allows us to infer that Zen meditation may effectively improve relevant characteristics of the cardiovascular system.
Interfacial Reactions and Bonding Strength of Sn-xAg-0.5Cu/Ni BGA Solder Joints
(2009-03-01)
Lin, K. S.
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Huang, H. Y.
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Chou, C. P.
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機械工程學系
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Department of Mechanical Engineering
The present study details the microstructure evolution of the interfacial intermetallic compounds (IMCs) layer formed between the Sn-xAg-0.5Cu (x = 1, 3, and 4 wt.%) solder balls and electroless Ni-P layer, and their bond strength variation during aging. The interfacial IMCs layer in the as-reflowed specimens was only (Cu,Ni)(6)Sn(5) for Sn-xAg-0.5Cu solders. The (Ni,Cu)(3)Sn(4) IMCs layer formed when Sn-4Ag-0.5Cu and Sn-3Ag-0.5Cu solders were used as aging time increased. However, only (Cu,Ni)(6)Sn(5) IMCs formed in Sn-1Ag-0.5Cu solders, when the aging time was extended beyond 1500 h. Two factors are expected to influence bond strength and fracture modes. One of the factors is that the interfacial (Ni,Cu)(3)Sn(4) IMCs formed at the interface and the fact that fracture occurs along the interface. The other factor is Ag(3)Sn IMCs coarsening in the solder matrix, and fracture reveals the ductility of the solder balls. The above analysis indicates that during aging, the formation of interfacial (Ni,Cu)(3)Sn(4) IMCs layers strongly influences the pull strength and the fracture behavior of a solder joint. This fact demonstrates that interfacial layers are key to understanding the changes in bonding strength. Additionally, comparison of the bond strength with various Sn-Ag-Cu lead-free solders for various Ag contents show that the Sn-1Ag-0.5Cu solder joint is not sensitive to extended aging time.
Electrical and optical properties of ZnO:Al thin films grown by magnetron sputtering
(2009-03-01)
Bai, Shr-Nan
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Tseng, Tseung-Yuen
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
The properties of transparent conductive ZnO:Al thin films grown by R.F. magnetron sputtering method are investigated. The working pressure (argon gas) is changed from 2.5 to 40.0 mTorr to study its influence on the characteristics of ZnO:Al thin films. The ZnO:Al thin films have better texture due to the increase in the surface mobility, which resulted from the increase in the mean free path of sputtering gas under lower working pressure. The microstructure of ZnO:Al films is found to be affected obviously by changing the working pressure. It is shown that the grain size of ZnO:Al thin films decreases with the increase of working pressure. The X-ray diffraction patterns indicate that the poor crystallized structure of ZnO:Al films is obtained at higher working pressure. Except 40 mTorr, the highly (002)-oriented ZnO:Al thin films can be found at the measured range of working pressure. Moreover, the growth rate of the films decreases from 1.5 to 0.5 nm/min as the working pressure increases from 2.5 to 40.0 mTorr. The results of optical transmittance measurement of ZnO:Al thin films reveal a high transmittance (> 80%) in visible region and exhibit a sharp absorption edge at wavelength about 350 nm.
Design of Power-Rail ESD Clamp Circuit With Ultra-Low Standby Leakage Current in Nanoscale CMOS Technology
(2009-03-01)
Wang, Chang-Tzu
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Ker, Ming-Dou
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電機學院
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College of Electrical and Computer Engineering
An ultra-low-leakage power-rail ESD clamp circuit, composed of the SCR device and new ESD detection circuit, has been proposed with consideration of gate current to reduce the standby leakage current. By controlling the gate current of the devices in the ESD detection circuit under a specified bias condition, the whole power-rail ESD clamp circuit can achieve an ultra-low standby leakage current. The new proposed circuit has been fabricated in a 1 V 65 nm CMOS process for experimental verification. The new proposed power-rail ESD clamp circuit can achieve 7 kV HBM and 325 V MM ESD levels while consuming only a standby leakage current of 96 nA at 1 V bias in room temperature and occupying an active area of only 49 mu m x 21 mu m.
Formation and Nonvolatile Memory Application of Ge Nanocrystals by Using Internal Competition Reaction of Si1.33Ge0.67O2 and Si2.67Ge1.33N2 Layers
(2009-03-01)
Chen, Wei-Ren
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Chang, Ting-Chang
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Hsieh, Yen-Ting
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Chang, Chun-Yen
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電子工程學系及電子研究所
In this study, the authors proposed a formation mechanism of Ge nanocrystals (NCs) embedded in the dielectric by using Si1.33Ge0.67O2 and Si2.67Ge1.33N2 films for nonvolatile memory (NVM) application. Because of internal competition reaction, this formation process reduced the thermal budget and eliminated the use of high-pressure H-2 treatment or steam process. The metal/oxide/insulator/oxide/silicon capacitor structure with NCs was also studied, and exhibited hysteresis characteristics after electrical operation. Transmission electron microscopy clearly shows the shape and density of NCs in the dielectric. In addition, the obvious memory window can be used to define "1" and "0" states at low-voltage program operation. Furthermore, good endurance and retention characteristics are exhibited for the Ge NCs embedded in SiNx structure. Besides, this technology is suitable for the current NVM fabrication and low-power device application.
儒家的現代性？
(國立陽明交通大學出版社, 2009-03-01)
楊儒賓
Application of Optimal Control and Fuzzy Theory for Dynamic Groundwater Remediation Design
(2009-03-01)
Chu, Hone-Jay
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Chang, Liang-Cheng
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土木工程學系
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Department of Civil Engineering
Obtaining optimal solutions for time-varying groundwater remediation design is a challenging task. A novel procedure first employs input/output data sets obtained by constrained differential dynamic programming (CDDP). Then the Adaptive-Network-Based Fuzzy Inference System (ANFIS), which is a fuzzy inference system (FIS) implemented in the adaptive network framework, is applied to acquire time-varying pumping rates. Results demonstrate that the FIS is an efficient way of groundwater remediation design.
The effect of AlN buffer growth parameters on the defect structure of GaN grown on sapphire by plasma-assisted molecular beam epitaxy
(2009-03-01)
Wong, Yuen-Yee
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Chang, Edward Yi
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Yang, Tsung-Hsi
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Chang, Jet-Rung
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Chen, Yi-Cheng
The defect structure of GaN film grown on sapphire by plasma-assisted molecular beam epitaxy (PAMBE) depends on the growth temperature and thickness of the aluminum nitride (AlN) buffer layer. High-resolution X-ray diffraction was used to measure symmetric (0 0 0 2) and asymmetric (1 0 (1) over bar 2) rocking curve (omega-scans) broadening, which allowed the estimation of screw threading dislocation (TD) and edge TD densities, respectively. For GaN grown on lower-temperature buffer, the density of screw TD was increased while the density of edge TD was decreased. Further examinations revealed that the edge TD was closely related to stress in GaN film and the screw TD was controlled by AlN surface roughness. Since the GaN defect was dominated by edge TD, the total TD was also effectively suppressed with the use of lower-temperature buffer with appropriate thickness. (C) 2009 Elsevier B.V. All rights reserved.
Purification, crystallization and preliminary X-ray analysis of an aminoacylhistidine dipeptidase (PepD) from Vibrio alginolyticus
(2009-03-01)
Chang, Chin-Yuan
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Hsieh, Yin-Cheng
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Wang, Ting-Yi
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Chen, Chun-Jung
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Wu, Tung-Kung
The aminoacylhistidine dipeptidase (PepD) protein encoded by Vibrio alginolyticus pepD was successfully overexpressed and characterized and the putative active-site residues responsible for metal binding and catalysis were identified. The purified enzyme contained two zinc ions per monomer. The recombinant dipeptidase enzyme, which was identified as a homodimer in solution, exhibited broad substrate specificity for Xaa-His dipeptides, with highest activity towards the His-His dipeptide. The purified protein was crystallized using the hanging-drop vapour-diffusion method. Preliminary crystallographic analysis showed that the crystal belonged to space group P6(1) or P6(5), with unit-cell parameters a = b = 80.42, c = 303.11 angstrom. The crystal contained two molecules per asymmetric unit and the predicted solvent content was 53.4%.
AlGaInAs/InP eye-safe laser pumped by a Q-switched Nd:GdVO(4) laser
(2009-03-01)
Huang, S. C.
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Chang, H. L.
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Su, K. W.
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Li, A.
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Liu, S. C.
An AlGaInAs quantum-well structure grown on a Fe-doped InP transparent substrate is developed to be a gain medium in a high-peak-power nanosecond laser at 1570 nm. Using an actively Q-witched 1064 nm laser to pump the gain chip, an average output power of 135 mW is generated at a pulse repetition rate of 30 kHz and an average pump power of 1.25 W. At a pulse repetition rate of 20 kHz, the peak output power is up to 290 W at a peak pump power of 2.3 kW.
Parameter Estimation/Sensitivity Analysis for an Aquifer Test with Skin Effect
(2009-03-01)
Chen, Yen-Ju
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Yeh, Hund-Der
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環境工程研究所
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Institute of Environmental Engineering
Aquifer information carried by aquifer test data may be affected by the presence of a finite thickness skin around the wellbore. The mathematical treatment for an aquifer accounting for the skin zone can be characterized by five parameters, that is, the outer radius of the skin zone and the transmissivity and storativity for each of the skin and aquifer zones. Sensitivity analysis was performed to examine the ground water flow behavior in the skin and aquifer zones in terms of the constant-head test (CHT) data. The simulated annealing procedure was applied to simultaneously determine the skin and aquifer parameters from the analysis of CHT data. Toward the previously mentioned goals, four suites of CHT data were analyzed in this article. The analyses of wellbore flow rate at the test well and the specific drawdown at the observation well gave accurate estimates for the skin and aquifer parameters, respectively. Only the skin thickness and both the skin and the aquifer diffusivities could be accurately estimated from the analysis of drawdown data in the observation well. The estimates for all skin and aquifer parameters from the composite analysis of flow rate and drawdown data were the most accurate. The results of sensitivity analyses and parameter estimations provide instructive references in the analysis of the skin-affected CHT data.
An intelligent questionnaire analysis expert system
(2009-03-01)
Chu, Yian-Shu
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Tseng, Shian-Shyong
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Tsai, Yu-Jie
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Luo, Ren-Jei
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資訊工程學系
In the questionnaire analysis, how to find a statistically significant difference between two or more groups in a continuous measure is one of the major problems in researches. However, it is difficult for researchers to solve the issue of finding possible statistically significant difference. There are two causes of this issue. The one is that the process of finding the statistically significant differences is highly dependent on researchers' intuition and experience, and the other is that the original questionnaire data may not be good enough to find the statistically significant differences. In this paper, we build a data warehouse and a forward-chaining rule-base expert system with three kinds of indicators, Increase, StepDown, and Dice, for drilling down the data warehouse to assist researchers in exploring the data to select appropriate statistics methods to find possible significant differences. The prototype of this expert system has been implemented, and the results of experiment about satisfaction survey showed finding the significant difference becomes easier, and users were interested in the idea of this system. (C) 2008 Elsevier Ltd. All rights reserved.
Current-mode design techniques in low-voltage 24-GHz RF CMOS receiver front-end
(2009-03-01)
Wu, Chung-Yu
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Wang, Wen-Chieh
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Shahroury, Fadi R.
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Huang, Zue-Der
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Zhan, Hao-Jie
A new high frequency CMOS current-mode receiver front-end composed of a current-mode low noise amplifier (LNA) and a current-mode down-conversion mixer has been proposed in the frequency band of 24 GHz and fabricated in 0.13-mu m 1P8M CMOS technology. The measurement of the current-mode receiver front-end exhibits a conversion gain of 11.3 dB, a noise figure (NF) of 14.2 dB, the input-referred 1-dB compression point (P-(1) (dB)) of -13.5 dBm and the input-referred third-order intercept point (P (IIP3)) of -1 dBm. The receiver dissipates 27.8 mW where the supply of LNA is 0.8 V and the supply of mixer is 1.2 V. The power consumption of output buffer is not included. The receiver front-end occupies the active area of 1.45 x 0.72 mm(2) including testing pads. The measured results show that the proposed current-mode approach can be applied to a high-frequency receiver front-end and is capable of low-voltage applications in the advanced CMOS technologies.
控制裝置及方法
(2009-03-01)
李嘉晃
;
林建良
本發明揭露一種控制裝置,其能供使用者以指示裝置對顯示裝置所顯示之物件進行控制。該控制裝置包含影像擷取模組、分離模組、定位模組、建構模組以及處理模組。影像擷取模組能記錄影像序列,並產生N個影像畫面。分離模組則根據指示裝置之特徵,分別自每個影像畫面截取出指示裝置所對應之指示裝置影像。而定位模組係用以分別計算每個影像畫面中指示裝置影像之特定點,以產生第一組特定點資訊。此外,建構模組依據預定條件與第一組特定點資訊產生運動軌跡。處理模組則分析運動軌跡並產生控制訊號,並且根據控制訊號對該物件進行控制。
A comprehensive study of temperature-dependent reflectance and photoluminescence of Zn1-xMnxO thin films grown on c-Al2O3
(2009-03-01)
Lin, D. Y.
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Lin, H. J.
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Wu, J. S.
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Chou, W. C.
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Yang, C. S.
We present a systematic study of temperature-dependent reflectance (R) and photoluminescence (PL) measurements on ZnMnO films grown by plasma-assisted molecular beam epitaxy. For the first time, the three free-exciton transitions FXA (Gamma(7c)-Gamma(u)(7v)), FXB (Gamma(7c)-Gamma(9v)), and FXC (Gamma(7c)-Gamma(l)(7v)) and the longitudinal-optical phonon replicas of FXB and FXC of ZnMnO films have been clearly observed in the R spectra. The parameters describing the activation energy and the temperature dependence of the transition energy and broadening have been extracted by fitting the experimental R and PL spectra. The spectral data of ZnMnO films not only show the deterioration of crystalline quality with increasing Mn composition fraction but also indicate the Mn clustering caused by Mn atom segregation.
Impedance-Isolation Technique for ESD Protection Design in RF Integrated Circuits
(2009-03-01)
Ker, Ming-Dou
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Hsiao, Yuan-Wen
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電機學院
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College of Electrical and Computer Engineering
An impedance-isolation technique is proposed tor on-chip ESD protection design tor radio-frequency (RF) integrated circuits (ICs), Which has been successfully verified in a 0.25-mu m CMOS process with thick top-layer metal. With the resonance of LC-tank at the operating frequently of the RF circuit, the impedance (especially, the parasitic capacitance) of the ESD protection devices can be isolated from the RF input node of low-noise amplifier (LNA). Therefore. the LNA can be co-designed with the proposed impedance-isolation technique to simultaneously achieve excellent RF performance and high ESD robustness. The power gain (S(21)-parameter) and noise figure of the ESD protection circuits with the proposed impedance-isolation techniques have been experimentally measured and compared, to those with the conventional double-diodes ESD Protection scheme. The proposed impedance-isolation technique had been demonstrated to he suitable for on-chip ESD protection design for RF ICs.