Browsing by Issue Date, starting with "2006-07-14"

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DSM-PLW: Single-pass mining of path traversal patterns over streaming Web click-sequences
(2006-07-14)
Li, Hua-Fu
;
Lee, Suh-Yin
;
Shan, Man-Kwan
;
資訊工程學系
;
Department of Computer Science
Mining Web click streams is an important data mining problem with broad applications. However, it is also a difficult problem since the streaming data possess some interesting characteristics, such as unknown or unbounded length, possibly a very fast arrival rate, inability to backtrack over previously arrived click-sequences, and a lack of system control over the order in which the data arrive. In this paper, we propose a projection-based, single-pass algorithm, called DSM-PLW (Data Stream Mining for Path traversal patterns in a Landmark Window), for online incremental mining of path traversal patterns over a continuous stream of maximal forward references generated at a rapid rate. According to the algorithm, each maximal forward reference of the stream is projected into a set of reference-suffix maximal forward references, and these reference-suffix maximal forward references are inserted into a new in-memory summary data structure, called SP-forest (Summary Path traversal pattern forest), which is an extended prefix tree-based data structure for storing essential information about frequent reference sequences of the stream so far. The set of all maximal reference sequences is determined from the SP-forest by a depth-first-search mechanism, called MRS-mining (Maximal Reference Sequence mining). Theoretical analysis and experimental studies show that the proposed algorithm has gently growing memory requirements and makes only one pass over the streaming data. (c) 2005 Elsevier B.V. All rights reserved.
Reactant gas transport and cell performance of proton exchange membrane fuel cells with tapered flow field design
(2006-07-14)
Liu, H. C.
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Yan, W. M.
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Soong, C. Y.
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Chen, Falin
;
Chu, H. S.
The objective of this work is to examine the reactant gas transport and the cell performance of a proton exchange membrane fuel cell (PEMFC) with a tapered flow channel design. It is expected that, with the reduction in the channel depth along the streamwise direction, the reactant fuel gas in the tapered channel can be accelerated as well as forced into the gas diffuser layer to enhance the electrochemical reaction and thus augment the cell performance. The effects of liquid water formation on the reactant gas transport are taken into account in the present study. Numerical predictions show that the cell performance can be enhanced with the fuel channel tapered, and the enhancement is more noticeable at a lower voltage. The results also reveal that the liquid water effect in general influences the cell performance and the effect becomes significant at lower voltages. (c) 2005 Elsevier B.V. All rights reserved.
Ultrafast carrier capture in charged InAs quantum dots
(2006-07-15)
Sun, K. W.
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Kechiantz, A.
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應用化學系
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應用化學系分子科學碩博班
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Department of Applied Chemistry
We report theoretical and experimental results of our investigation on carrier capture and relaxation processes in undoped and modulation-doped InAs/GaAs self-assembled quantum dots (QDs). We find that carrier capture and relaxation in the ground state is faster in the modulation-doped quantum dots compared to the case in neutral dots at an excitation level as low as one electron-hole pair per dot. The ultrafast photoluminescence (PL) transient rise time observed in the charged dots is attributed to the relaxing of strained field induced by the presence of cold carriers in the dots. The Hamiltonian of electron's interaction with local vibrating field and carrier capture time are also calculated. (c) 2006 Elsevier B.V. All rights reserved.
A composite traffic flow modeling approach for incident-responsive network traffic assignment
(2006-07-15)
Sheu, JB
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運輸與物流管理系註：原交通所+運管所
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Department of Transportation and Logistics Management
This paper presents a hybrid traffic simulation-based model to address the network traffic route choice issue under conditions of lane-blocking incidents on surface streets. The proposed approach includes four sequential mechanisms: (1) link flow loading, (2) link traffic moving, (3) link cost calculation, and (4) searching the shortest path. To deal with the traffic flows moving on lane-blocking links, specific incident-induced link traffic flow models, which are extended from the Lighthill-Whitham (L-W for short) model, are formulated. A simulation-based approach is then proposed to determine the instantaneous shortest path associated with each vehicle approaching to each given intersection on the network. In addition, numerical examples associated with diverse incident scenarios are investigated. The numerical results demonstrate the competitiveness of the proposed simulation-based method by reducing the network-wide path travel time by 11.4% and the incident impact on link traffic flows by 66.7% in comparison with the Paramics traffic simulator. It is expected that this study can provide linkage between the fields of incident management and dynamic traffic assignment that will allow the development of such related technologies as real-time incident-responsive route guidance and incident management systems. (c) 2005 Elsevier B.V. All rights reserved.
Method for identifying transcription factor binding sites in yeast
(2006-07-15)
Tsai, Huai-Kuang
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Huang, Grace Tzu-Wei
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Chou, Meng-Yuan
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Lu, Henry Horng-Shing
;
Li, Wen-Hsiung
Motivation: Identifying transcription factor binding sites (TFBSs) is helpful for understanding the mechanism of transcriptional regulation. The abundance and the diversity of genomic data provide an excellent opportunity for identifying TFBSs. Developing methods to integrate various types of data has become a major trend in this pursuit. Results: We develop a TFBS identification method, TFBSfinder, which utilizes several data sources, including DNA sequences, phylogenetic information, microarray data and ChIP-chip data. Fora TF, TFBSfinder rigorously selects a set of reliable target genes and a set of non-target genes (as a background set) to find overrepresented and conserved motifs in target genes. A new metric for measuring the degree of conservation at a binding site across species and methods for clustering motifs and for inferring position weight matrices are proposed. For synthetic data and yeast cell cycle TFs, TFBSfinder identifies motifs that are highly similar to known consensuses. Moreover, TFBSfinder outperforms well-known methods.
Phase characterization and tunable photoluminescence of Eu-doped strontium-substituted nanohalophosphate
(2006-07-15)
Yang, Chih-Cheng
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Chen, San-Yuan
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Liu, Dean-Mo
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交大名義發表
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National Chiao Tung University
Nanocrystalline Eu-doped powders, Ca5-xSrx(PO4)(3)(OH):Eu3+, were prepared from chemical solutions at room temperature. The crystalline phase and photo luminescence (PL) properties of the halophosphate powders were studied in terms of solution pH value and annealing atmosphere. At pH = 2, both Ca8.3Sr1.7(PO4)(6)Cl-2 and Ca8.3Sr1.7(PO4)(6)(OH)(2) phases were detected, but an increase in solution pH value over 7 led to the formation of only Ca8.3Sr1.7(PO4)(6)(OH)(2) phase. After annealed at 850 degrees C, the sample prepared in pH = 2 solution shows stronger blue emission than that prepared in pH = 10 in the reducing atmosphere. However, for the samples annealed in air atmosphere, the blue emission still can be observed that can be attributed to the reduction of Eu3+ -> Eu2+. The relative intensity of blue to red emissions is dominated not only by annealing atmosphere but also by crystalline phase formed in the sample. These results indicate that the PL properties can be tunable by controlling the solution pH value (crystalline phase) and changing annealing atmosphere. (c) 2006 Elsevier B.V. All rights reserved.
Nanomechanical characteristics of BaxSr1-xTiO3 thin films
(2006-07-15)
Jian, Sheng-Rui
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Chang, Win-Jin
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Fang, Te-Hua
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Ji, Liang-Wen
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Hsiao, Yu-Jen
The nanomechanical properties of barium strontium titanate (BaxSr1-xTiO3, x=0-1) deposited on a silicon substrate were investigated using the metalorganic deposition method. The characteristics of the BaxSr1-xTiO3 thin film's crystalline structure and surface roughness were achieved by means of X-ray diffraction (XRD) and atomic force microscopy (AFM). The results indicated that as the Ba content was decreased and therefore the Sr content was increased a lower leakage current density and a smaller grain size were obtained. Also the mechanical properties such as hardness, Young's modulus and contact stress-strain were also studied by nanoindentation. (c) 2006 Elsevier B.V. All rights reserved.
A novel use of t-packings to construct d-disjunct matrices
(2006-07-15)
Fu, HL
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Hwang, FK
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應用數學系
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Department of Applied Mathematics
A t-packing is an ordered pair (V, P) where V is a nu-set and P is a collection of k-subsets (blocks) of V such that each t-subset of V occurs in at most one block of P. If each t-subset of V occurs in exactly one block of P, then (V, P) is known as a Steiner (t, k, nu)-design. In this paper, we explore a novel use of t-packings to construct d-disjunct matrices. (c) 2006 Elsevier B.V. All rights reserved.
An agent-based system to discover protein-protein interactions, identify protein complexes and proteins with multiple peptide mass fingerprints
(2006-07-15)
Lee, TY
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Horng, JT
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Juan, HF
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Huang, HD
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Wu, LC
Proteins "work together" by actually binding to form multicomponent complexes that carry out specific functions. Proteomic analyses based on the mass spectrum are now key methods to determine the components in protein complexes. The protein-protein interaction or functional association may be known to exist among the extracted protein spots while analyzing the proteins on the 2D gel. In this study, we develop an agent-based system, namely AgentMultiProtIdent, which integrated two protein identification tools and a variety of databases storing relations among proteins and used to discover protein-protein interactions and protein functional associations, and identify protein complexes and proteins with multiple peptide mass fingerprints as input. The system takes Multiple Peptide Mass Fingerprints (PMFs) as a whole in the protein complex or protein identification. With the relations among proteins, it may greatly improve the accuracy of identification of protein complexes. Also, possible relationship of the multiple peptide mass fingerprints, such as ontology relation, can be discovered by our system, especially in the identification of protein complexes.
具低壓差動訊號（LVDS）與低擺幅差動訊號（RSDS）規格之平面顯示器高速輸入輸出緩衝器
(2006-07-16)
柯明道
;
莊凱嵐
本發明提供一種具低壓差動訊號(LUDS)與低擺幅差動訊號(RSDS)規格之平面顯示器高速輸入輸出緩衝器，其係將運用於平面顯示器系統介面的低電壓差動訊號傳輸規格與更小擺幅差動訊號傳輸規格之輸入輸出緩衝器整合於同一輸入輸出緩衝器電路中，且此輸入輸出緩衝器的資料傳輸速度可以到達1.2 Gb/s，其可以支援解析度為UXGA(1600×1200像素)的平面顯示器。因此本發明提供一種輸入輸出緩衝器可適用於兩種標準傳輸介面的，不但可節省電路面積，更可在高速資料傳輸下運作，並且其在睡眠模式下可節省電源的消耗。
Study of void formation due to electromigration in flip-chip solder joints using Kelvin bump probes
(2006-07-17)
Chang, Y. W.
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Liang, S. W.
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Chen, Chih
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材料科學與工程學系
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Department of Materials Science and Engineering
Kelvin bump probes were fabricated in flip-chip solder joints, and they were employed to monitor the void formation during electromigration. We found that voids started to form at approximately 5% of the failure time under 0.8 A at 150 degrees C, and the bump resistance increased only 0.02 m Omega in the initial stage of void formation. Three-dimensional simulation was performed to examine the increase in bump resistance at different stages of void formation, and it fitted the experimental results quite well. This technique provides a systematic way for investigating the void formation during electromigration. (c) 2006 American Institute of Physics.
High-resolution intelligent rotor machine diagnostic system and method
(2006-07-18)
Bai
;
Ming-Sian
;
Hung
;
Ming-Hung
;
Huang
The present invention relates to a smart system and method of performing high-resolution frequency order analysis/diagnosis on rotor, in which such system is characterized in that capable of performing order analysis via a Kalman filter or a RLS (Recursive Least Square) algorithm while determining the failure status based on the Fuzzy theory. The smart system of present invention comprises a data acquisition means, a bench data setup means, a STFT time-spectra analysis/re-sampled order tracking means, a Kalman filter or RLS algorithmic means, a fuzzy diagnosis means and a window interface (e.g., GUI) while repeatedly making use the functions of those means so as to achieve the real-time diagnosis on rotor.
繆思的星期五文學沙龍11
(2006-07-19)
本報訊
5.2 GHz SiGe HBT upconverter using active-inductor LC current mirror
(2006-07-20)
Wu, T. -H.
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Meng, C.
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Wu, T. -H.
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電信工程研究所
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Institute of Communications Engineering
A compact 5.2 GHz upconversion micromixer using the 0.35 mu m SiGe HBT technology is demonstrated. A bandpass and area-saving LC current mirror using the active inductor is incorporated to increase the conversion gain. The demonstrated upconverter has conversion gain of -3.5 dB, OP(1dB) of -10 dBm, and O1P(3) of 0 dBm.
繆司的星期五文學沙龍11
(2006-07-20)
本報訊
Prevention and amelioration of acetaminophen toxicity with tea melanin
(2006-07-20)
Huang, Guewha Steven
The present invention relates to a method for preventing and/or reducing the toxicity of acetaminophen which comprises administering to a mammal an amount of tea melanin before or simultaneous with dosage of acetaminophen, a pharmaceutical composition containing tea melanin, and a pharmaceutical composition containing tea melanin and acetaminophen for preventing and/or reducing the toxicity of acetaminophen.
Application of SiO2-poly(dimethylsiloxane) hybrid material in the fabrication of amperometric biosensor
(2006-07-21)
Ho, Wei-Jen
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Yuan, Chiun-Jye
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Reiko, Ohara
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生物科技學系
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Department of Biological Science and Technology
Silica xerogel was widely used in the development of biosensors by coupling the desired biological components to various transducers. Unfortunately, the application of xerogels is limited due to their poor mechanical properties and poor structural maintenance of entrapped biomaterials. In this study, the availability of poly(dimethylsiloxane) (PDMS)-modified silica sol-gel (TEOS/PDMS Ormosil) glass in the immobilization of enzymes and its application in the fabrication of amperometric biosensor was investigated. We demonstrated that most of activity of encapsulated horseradish peroxidase can be preserved in PDMS-modified SiO2 glass compared with conventional silica xerogel. The synthesized monoliths exhibited high transparency and crack-free. The enzyme electrode based on glucose oxidase encapsulated TEOS/PDMS Ormosil glass on Pd electrode was fabricated and characterized electrochemically. The characteristics of the biosensor were studied by cyclic voltammetry and chronoamperometry. The biosensor exhibited a series of good properties: high sensitivity (1.63 mu A mM(-1) analyte), short response time and high reproducibility. The results indicate that TEOS/PDMS Ormosil glass has great potential to the immobilization of biomaterials as well as the fabrication of biosensors. (c) 2006 Elsevier B.V. All rights reserved.
Dibenzothiophene/oxide and quinoxaline/pyrazine derivatives serving as electron-transport materials
(2006-07-21)
Huang, Tai-Hsiang
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Whang, Wha-Tzong
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Shen, Jiun Yi
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Wen, Yuh-Sheng
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Lin, Jiann T.
A series of 2,8-disubstituted dibenzothiophene and 2,8-disubstituted dibenzothiophene-SS-dioxide derivatives containing quinoxaline and pyrazine moieties are synthesized via three key steps: i) palladium-catalyzed Sonogashira coupling reaction to form dialkynes; ii) conversion of the dialkynes to diones; and iii) condensation of the diones with diamines. Single-crystal characterization of 2,8-di(6,7-dimethyl-3-phenyl-2-quinoxalinyl)-5H-5 lambda(6)-dibenzo[b,d]thiophene-5,5-dione indicates a triclinic crystal structure with space group P1 and a non-coplanar structure. These new materials are amorphous, with glass-transition temperatures ranging from 132 to 194 degrees C. The compounds (Cpd) exhibit high electron mobilities and serve as effective electron-transport materials for organic light-emitting devices. Double-layer devices are fabricated with the structure indium tin oxide (ITO)/Qn/Cpd/LiF/Al, where yellow-emitting 2,3-bis[4-(N-phenyl-9-ethyl-3-carbazolylamino)phenyl]quinoxaline (Qn) serves as the emitting layer. An external quantum efficiency of 1.41 %, a power efficiency of 4.94 lm W-1, and a current efficiency of 1.62 cd A(-1) are achieved at a current density of 100 mA cm(-2).
Real-time human identification using a pyroelectric infrared detector array and hidden Markov models
(2006-07-24)
Fang, Jian-Shuen
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Hao, Qi
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Brady, David J.
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Guenther, Bob D.
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Hsu, Ken Y.
This paper proposes a real-time human identification system using a pyroelectric infrared ( PIR) detector array and hidden Markov models ( HMMs). A PIR detector array with masked Fresnel lens arrays is used to generate digital sequential data that can represent a human motion feature. HMMs are trained to statistically model the motion features of individuals through an expectation-maximization ( EM) learning process. Human subjects are recognized by evaluating a set of new feature data against the trained HMMs using the maximum-likelihood ( ML) criterion. We have developed a prototype system to verify the proposed method. Sensor modules with different numbers of detectors and different sampling masks were tested to maximize the identification capability of the sensor system. (c) 2006 Optical Society of America.
Improved luminance intensity of InGaN-GaN light-emitting diode by roughening both the p-GaN surface and the undoped-GaN surface
(2006-07-24)
Peng, Wei Chih
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Wu, Yew Chung Sermon
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材料科學與工程學系
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Department of Materials Science and Engineering
The InGaN-GaN epitaxial films were grown by low-pressure metal-organic chemical vapor deposition on a sapphire substrate, and then the light-emitting diode (LED) with double roughened (p-GaN and undoped-GaN) surfaces was fabricated by surface-roughening, wafer-bonding, and laser lift-off technologies. It was found that the front side luminance intensity of double roughened LED was 2.77 times higher than that of the conventional LED at an injection current of 20 mA. The backside luminance intensity was 2.37 times higher than that of the conventional LED. This is because the double roughened surfaces can provide photons multiple chances to escape from the LED surface, and redirect photons, which were originally emitted out of the escape cone, back into the escape cone.