Browsing by Issue Date, starting with "2006-03-01"

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New analytical solutions for groundwater flow in wedge-shaped aquifers with various topographic boundary conditions
(2006-03-01)
Yeh, HD
;
Chang, YC
;
環境工程研究所
;
Institute of Environmental Engineering
The hydraulic head distribution in a wedge-shaped aquifer depends on the wedge angle and the topographic and hydrogeological boundary conditions. In addition, an equation in terms of the radial distance with trigonometric functions along the boundary may be suitable to describe the water level configuration for a valley flank with a gentle sloping and rolling topography. This paper develops a general mathematical model including the governing equation and a variety of boundary conditions for the groundwater flow within a wedge-shaped aquifer. Based on the model, a new closed-form solution for transient flow in the wedge-shaped aquifer is derived via the finite sine transform and Hankel transform. In addition, a numerical approach, including the roots search scheme, the Gaussian quadrature, and Shanks' method, is proposed for efficiently evaluating the infinite series and the infinite integral presented in the solution. This solution may be used to describe the head distribution for wedges that image theory is inapplicable, and to explore the effects of the recharge from various topographic boundaries on the groundwater flow system within a wedge-shaped aquifer. (c) 2005 Elsevier Ltd. All rights reserved.
Optical beams in sub-strongly non-local nonlinear media: A variational solution
(2006-03-01)
Guo, Q
;
Luo, B
;
Chi, S
;
光電工程學系
;
Department of Photonics
Discussed is the propagation of optical beams in non-local nonlinear media modelled by 1 + 1D non-local nonlinear Schrodinger equation (NNLSE). In the sub-strongly non-local case, an approximate analytical solution is obtained for an arbitrary response function by a variational approach. Described by a combination of the Jacobian elliptic functions, the solution is periodic, and its period depends on not only the input power but also the initial beam width, which is confirmed by the numerical simulation of the NNLSE. (c) 2005 Elsevier B.V. All rights reserved.
Decision traps and competence dynamics in changeable spaces
(2006-03-01)
Yu, PL
;
Chianglin, CY
;
資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
There are many parameters in challenging decision problems, including the alternatives, the criteria, resources, the perception of decision problems, decision makers and their psychological states, information inputs from the environment, and self-suggestion, etc. At any moment of time, some of these parameters can catch our attention, called alerted parameters; some cannot, called unalerted parameters. Some parameters are visible, some are invisible. In addition, the parameters themselves can vary over certain ranges or domains. All of these make challenging decision problems very complex. We call this kind of problems as decision problems with changeable spaces (parameters). We may focus on certain parameters with certain assumed values to find an "optimal" solution, which may lead to solve wrong problem with bad solution. Quite often, our focus may be-just a small part of what we know, or just a part of what we are most familiar with. We may often neglect what we are not familiar with, and pay no attention to what we do not know. As a consequence, we may see just a small part of the problem domain (including all parameters and their possible variations over time). The portion (of the problem domain) that we cannot see is our decision blind. Suppose our alerted domain (those parameters and their variations that are currently under our consideration) to be fixed in only a small part of the problem domains. Then very likely we could end up with a serious mistake. This situation is known as decision trap. In this article, we will introduce a systematic scheme, based on habitual domain theory, to help us reduce decision blinds and avoid decision traps so that we could make decision with good quality. Then we will also introduce the concept of competence set analysis to help us cope with challenging decision problems. This including: (i) how to effectively expand our competence (resources, skill, know-how, information, ideas, effort, etc.) as to solve a given problem effectively; and (ii) given a set of competence, how to maximize its value by solving a set of value added problems. Furthermore, we will introduce innovation dynamics which describe the dynamics of how to solve a set of problems with our existent or acquired competence (to relieve the pains or frustrations of "certain customers or decision makers" at certain situations) as to create value, and how to distribute this created value so that we can continuously expand out competence set to solve more challenging problems and create more value.
Wrinkle rendering of terrain models in Chinese landscape painting
(2006-03-01)
Way, DL
;
Shih, ZC
;
資訊工程學系
;
Department of Computer Science
Landscapes have been the main theme in Chinese painting for over one thousand years. Chinese ink painting is a form of nonphotorealistic rendering. Terrain is the major subject in Chinese landscape painting, and surface wrinkles are important in conveying the orientation of Mountains and contributing to the atmosphere. Over the centuries, masters of Chinese landscape painting have developed various kinds of wrinkles. This work develops a set of novel methods for rendering wrinkles in Chinese landscape painting. A three-dimensional terrain is drawn as an outline and wrinkles, using information oil the shape, shade and orientation of the terrain's polygonal surface. The major contribution of this work lies ill the modeling and implementation of six major types of wrinkles on the surface of terrain. using traditional Chinese brush techniques. Users can select a style of wrinkle and input parameters to control the desired effect. The proposed method then completes the painting process automatically.
Impact of STI on the reliability of narrow-width pMOSFETs with advanced ALD N/O gate stack
(2006-03-01)
Chung, SS
;
Yeh, CH
;
Feng, HJ
;
Lai, CS
;
Yang, JJ
For the first time, a shallow trench isolation (STI)-induced enhanced degradation in pMOSFETs for ultrathin gate oxide devices has been observed. The ID degradation is enhanced as a reduction in the gate width and the hot carrier (HC) or negative bias temperature instability (NBTI) effect. Extensive studies have been compared for atomic layer deposition (ALD)-grown and plasma-treated oxide pMOSFETs. Different temperature dependences were observed. At room temperature, hole trap is dominant for the device degradation, in which holetrap-induced V-T is significant, whereas at high temperature under NBTI stress, interface trap becomes more significant, which dominates the device ID degradation. In addition, the V-T rolloff can be modeled as a width narrowing effect specifically for STI. More importantly, the NBTI-induced interface/oxide traps are strongly related to the hydrogen and N-2 content in the gate oxide formation process. The interface trap generation is suppressed efficiently using the ALD-grown gate oxide. These results provide a valuable guideline for the understanding of the HC and NBTI reliabilities in an advanced ALD-grown gate oxide processes/devices.
Width-dependent anomalous CoSix sheet resistance change by Ti and TiN capping process
(2006-03-01)
Chen, YM
;
Tu, GC
;
Wang, YL
;
材料科學與工程學系
;
Department of Materials Science and Engineering
In order to minimize the circuit propagation delay, self-aligned silicide (salicide) technology has been widely used to reduce source/drain/gate spreading resistance and contact resistance. Cobalt silicide (CoSi2) is the most popular silicide material beyond 0.25 mu m node as it has less line width dependence than titanium silicide (TiSi2). Cobalt on silicon with TiN capping or Ti capping has been widely applied for years and demonstrates a very promising manufacturability and scalability toward 0.1 mu m and below. In this work, width-dependent sheet resistance change was studied and the anomalous sheet resistance behavior was observed to be very different for these two different capping materials. The different silicide profiles around active regions and shallow trench isolation (STI) interface were identified to be the root cause for this difference. The stress built at STI and active regions played an important role for silicide formation. Experimental results can conclude that capping material selection is very crucial for deep submicron ultralarge silicon integrated (ULSI) circuit. (c) 2005 Elsevier B.V. All rights reserved.
Measuring production performance of different product mixes in semiconductor fabrication
(2006-03-01)
Chung, Shu-Hsing
;
Pearn, Wen Lea
;
Lee, Amy H. I.
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
In a competitive market, a company needs to fully utilize its current capacity in order to acquire higher profit. The purpose of this paper is to present an effective approach to find a set of product mix efficient for the company to achieve the optimal production. Simulation is first used to generate the data of performance measures of different product mixes in a semiconductor fabricator. Data Envelopment Analysis (DEA) is applied next to measure multiple inputs and outputs, without pre-assigning weights, for product mixes, and an efficiency score for producing each product mix relative to other mixes can be obtained. The results provide guidance for a fab in accepting orders when its capacity cannot fully satisfy all the product demand. Significance: This paper applied the DEA method to evaluate the production performance with different product mixes in a semiconductor fabricator. The results provide guidance to the fabricator regarding accepting orders to maximize the production efficiency and the profit, while considering several other important input and output factors that maintain production smoothing.
與黃錦樹談文學史書寫的暴力問題
(國立陽明交通大學出版社, 2006-03-01)
邱貴芬
光子晶體波導之結構
(2006-03-01)
趙遠鳳
;
楊宗哲
;
李文德
一種光子晶體波導之結構，其包含一平面型光子晶體波導單元、一以上設置於平面型光子晶體波導單元之二端之矽質波導單元、一以上設置於各矽質波導單元相對應一面之側形漸變式單元及一設置於各側形漸變式單元上且位於矽質波導單元之輸出／輸入端以上之缺陷柱。藉此，可增加光子晶體波導的耦合效率。
Improved fiber Bragg grating array OFFH-CDMA system using a novel frequency-overlapping multigroup method
(2006-03-01)
Peng, WR
;
Lin, WP
;
Chi, S
;
光電工程學系
;
Department of Photonics
The authors propose a novel frequency-overlapping multigroup scheme for a passive all-optical fast-frequency hopped code-division multiple-access (OFFH-CDMA) system based on fiber Bragg grating array (FBGA). In the conventional scheme, the users are assigned those codes constructed on the nonoverlapping frequency slots, and therefore the bandgaps; between the adjacent gratings are wasted. To make a more efficient use of the optical spectrum, the proposed scheme divided the users into several groups, and assigned the codes, which interleaved to each other to the different groups. In addition to the higher utilization of the spectrum, the interleaved nature of the frequency allocations of different groups will make the groups less correlated and, hence, lower the multiple-access interference (MAI). The corresponding codeset and its constraints for this new scheme are also developed and analyzed. The performance of the system in terms of the correlation functions and bit error rate (BER) are given in both the conventional and the proposed schemes. The numerical results show that, with the multigroup scheme, performance is much improved compared to the conventional scheme.
Phase transformations in a Cu-25at.%Al-7.5at.%Mn alloy
(2006-03-01)
Yang, SY
;
Liu, TF
;
材料科學與工程學系
;
Department of Materials Science and Engineering
The as-quenched microstructure of the Cu-25at.%Al-7.5at.%Mn alloy was D0(3) phase containing extremely fine L-J precipitates (the L-J phase is a new type of precipitate, which was firstly observed and identified by Liu and Jena (designated L-J phase) in a Cu-2.2-Mn0.8Al alloy.). When the as-quenched alloy was aged at temperatures ranging from 500 degrees C to 700 degrees C, the phase transition sequence was found to be (gamma-brass + L-J + D0(3)) (gamma-brass + L-J + B2) -> beta This result is different from that reported by previous workers in Cu-25at.%Al-(0-8)at.%Mn alloys. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Concentration and fate of persistent organochlorine pesticides in estuarine sediments using headspace solid-phase microextraction
(2006-03-01)
Chang, SM
;
Doong, RA
;
環境工程研究所
;
Institute of Environmental Engineering
The concentration and fate of persistent organochlorine pesticides (OCPs) in estuarine surface sediments in Erh-jen and Lan-yang rivers, Taiwan were investigated using headspace solid-phase microextraction (HSSPME) method to evaluate the possible pollution potential and guideline for OCP concentrations in Taiwan. The HSSPME method exhibits a good analytical performance with low detection limits for OCP determination in sediment. In addition, results obtained using the developed HSSPME method were in good agreement with those obtained using Soxhlet extraction in a certified sample. The developed analytical method was further applied to the determination of concentrations of OCP residues in surface sediments from the estuaries of the selected rivers in Taiwan. A total of 20 surface sediments from each river was collected from 10 sampling stations. The total OCP concentrations in sediments from Erh-jen River ranged from 0.17 to 5.04 ng/g-dw with the mean values of 0.25-1.24 ng/g-dw for HCHs, 0.10-0.89 ng/g-dw for cyclodienes and 0.16-0.64 ng/g-dw for DDTs. The concentrations of OCPs in sediments from Lan-yang River were in the range 0.37-0.9 ng/g-dw with an average of lower than 0.5 ng/g-dw. HCHs and DDTs were abundant in the estuarine sediments from the selected rivers. Results obtained in this study show that the origin of OCPs in the surface sediments from Erh-jen River is a combination of erosion of the weathered soils and long-range atmospheric transport, while the OCP concentrations found in Lan-yang River could be regarded as the background levels of OCPs in Taiwan. (c) 2005 Elsevier Ltd. All rights reserved.
The 3rd Asian Conference on Chemical Vapor Deposition (3rd Asian-CVD), Taipei, Taiwan, November 12-14, 2004 - Preface
(2006-03-01)
Feng, ZC
;
Chen, CF
;
Williams, K
;
Shan, W
;
交大名義發表
Experimental evaluation of compressive behavior of orthotropic steel plates for the new San Francisco Oakland Bay Bridge
(2006-03-01)
Chou, C. C.
;
Uang, C. M.
;
Seible, F.
;
土木工程學系
;
Department of Civil Engineering
Compression tests were conducted on two reduced-scale orthotropic plates to verify the design strength of steel box girders for the new San Francisco-Oakland Bay Bridge. The first specimen was composed of three longitudinal closed ribs and a top deck plate. It failed in global buckling, followed by local buckling in the deck plate and ribs. The second specimen, which was composed of four longitudinal T-shaped ribs and a bottom deck plate, experienced global buckling as well as local buckling in the ribs and the deck plate. The ultimate strength and failure mode of both specimens were evaluated by two bridge design specifications: the 1998 AASHTO load and resistance factor design specification and the 2002 Japanese JRA specification. Findings from code comparisons showed that: (1) Sufficient flexural rigidity of ribs were provided for both specimens; (2) the JRA specification slightly overestimated the ultimate strength of both specimens; and (3) neither specifications predicted the observed buckling sequence in Specimen 2. A general-purpose nonlinear finite element analysis program (ABAQUS) was used to perform correlation study. The analysis showed that the ultimate strength and postbuckling behavior of the specimens could be reliably predicted when both the effects of residual stresses and initial geometric imperfections were considered in the model.
Robust beamforming of microphone array using H infinity adaptive filtering technique
(2006-03-01)
Hu, JS
;
Liu, WH
;
Cheng, CC
;
電控工程研究所
;
Institute of Electrical and Control Engineering
In ASR (Automatic Speech Recognition) applications, one of the most important issues in the real-time beamforming of microphone arrays is the inability to capture the whole acoustic dynamics via a finite-length of data and a finite number of array elements. For example, the reflected source signal impinging from the side-lobe direction presents a coherent interference, and the non-minimal phase channel dynamics may require an infinite amount of data in order to achieve perfect equalization (or inversion). All these factors appear as uncertainties or un-modeled dynamics in the receiving signals. Traditional adaptive algorithms such as NLMS that do not consider these errors will result in performance deterioration. In this paper, a time domain beamformer using H-infinity filtering approach is proposed to adjust the beamforming parameters. Furthermore, this work also proposes a frequency domain approach called SPFDBB (Soft Penalty Frequency Domain Block Beamformer) using H-infinity filtering approach that can reduce computational efforts and provide a purified data to the ASR application. Experimental results show that the adaptive H-infinity filtering method is robust to the modeling errors and suppresses much more noise interference than that in the NLMS based method. Consequently, the correct rate of ASR is also enhanced.
《西域威龍》：成龍的華人男性形象
(國立陽明交通大學出版社, 2006-03-01)
趙庭輝
本文的研究目的在於，探索好萊塢電影文本如何再現華人男性形象、以及好萊塢電影文本有關華人男性身體與陽剛特質的銀幕再現。本文認為，《西域威龍》這部電影的文本特殊性是，成龍將香港喜劇功夫片與美國西部片結合，並且自願與好萊塢電影工業的東方主義意識型態共謀，為東西方觀影者，建構一個混淆地理區域、種族藩籬與文化界限的可能。本文以電影研究的文本分析為基礎，針對《西域威龍》進行文本解構與詮釋，涵蓋三個層面的討論，包括影像美學、性別政治與敘事法則。本文發現，透過大遠景鏡頭與空中遙攝鏡頭的俯視角度，再現美國西部宏偉壯闊的地理空間，而成龍則建構相當獨特的喜劇功夫片影像美學；成龍的華人男性形象是陰性化的他者、被虐狂的身體表演，以及情慾壓抑；藉由諧仿效果與嘲弄手法、以及語言遊戲的耍弄，成龍成為被美國白種人譏諷的對象。
Orientation of adsorbed dipolar molecules: A conical well model
(2006-03-01)
Liao, YY
;
Chen, YN
;
Chou, WC
;
Chuu, DS
;
電子物理學系
Orientation of single and two coupled polar molecules irradiated by a single laser pulse under a conical-well model is investigated theoretically. The orientation of a single hindered rotor shows a periodic behavior. In particular, the amplitude of the oscillation is sensitive to the degree of alternation of the laser field. Crossover from field-free to hindered rotation is observed by varying the hindering angle for different heights of conical wells. For a small hindering potential and angle, time-averaged orientation differs greatly from that for an infinite one. The orientation at a large hindering angle shows irregularlike behavior under strong dipole-dipole interaction. Entanglement induced by the dipole-dipole interaction is also calculated for the coupled-rotor system, in which the time-averaged entropy increases monotonically as the hindering angle is increased. The competition between the confinement effect and dipole interaction is found to dominate the behavior of the coupled-rotor system.
Template-assisted synthesis of mesoporous tubular carbon nanostructure by chemical vapor infiltration method
(2006-03-01)
Lo, AY
;
Huang, SJ
;
Chen, WH
;
Peng, YR
;
Kuo, CT
A novel synthesis route for fabrication of tubule mesoporous carbon by chemical vapor infiltration method using a mesoporous silica template is reported. Powder X-ray diffraction and pore size analysis revealed that the nano-sized carbon material consists of three-dimensional framework structure and possesses a bimodal pore distribution with average pore diameters of 1.5 and 3.3 nm. The formation of the former pore is ascribed due to removal of the silica template, whereas the latter represents pore size of tubule carbon with ordered structure having an average wall thickness corresponding to about 1.3 layers of graphitic sheets, as verified by Raman spectroscopy and electron microscopy. (c) 2005 Published by Elsevier B.V.
High efficiency microwave digestion purification of multi-walled carbon nanotubes synthesized by thermal chemical vapor deposition
(2006-03-01)
Chen, CM
;
Chen, M
;
Peng, YW
;
Yu, HW
;
Chen, CF
Multi-walled carbon nanotubes (MWCNTs) synthesized by thermal chemical vapor deposition (Thermal CVD) have been successfully purified by high efficient microwave digestion purification method. In this paper, microwave digestion method was introduced to purify carbon nanotubes, because that acid can absorb microwave energy rapidly and dissolve metal efficiently in this method. MWCNTs were placed in 100 ml TFM (thennally resistant form of Teflon) vessels with 50 ml 5 M nitric acid. First, the temperature ramped up to 210 degrees C in 30 min and then kept for 10, 20, 30 to 120 min to digest the catalyst. The efficiency of this method was analyzed by thermogravimetric analysis (TGA) and the results showed that the catalyst content dropped from 10.39% to 1.75% only in 10-min digestion and 1.03% for 120 min treatment. Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM) were applied to analyze the property and structure of raw and purified MWCNTs. This study presents a highly efficient and non-destructive purification method for high purity MWCNTs which can be provided in many applications or intrinsic property studies. (c) 2005 Elsevier B.V All rights reserved.
Simulation of flow past a square cylinder by parallel lattice Boltzmann method using multi-relaxation-time scheme
(2006-03-01)
Wu, JS
;
Shao, YL
;
機械工程學系
;
Department of Mechanical Engineering
The flows past a square cylinder in a channel are simulated using the multi-relaxation-time (MRT) model in the parallel lattice Boltzmann BGK method (LBGK). Reynolds numbers of the flow are in the range of 100 similar to 1,850 with blockage ratio, 1/6, of cylinder height to channel height, in which the single-relaxation-time (SRT) scheme is not able to converge at higher Reynolds numbers. Computed results are compared with those obtained using the SRT scheme where it can converge. In addition, computed Strouhal numbers compare reasonably well with the numerical results of Davis (1984).