Browsing by Issue Date, starting with "2007-11-01"

Now showing 1 - 20 of 58808

Improved stress reliability of analog TiHfO metal-insulator-metal capacitors using high-work-function electrode
(2007-11-01)
Cheng, Chun-Hu
;
Chiang, Kuo-Cheng
;
Pan, Han-Chang
;
Hsiao, Chien-Nan
;
Chou, Chang-Pin
We have studied the reliability of high-K (K similar to 49) TixHf1-xO (x similar to 0.67) metal-insulator-metal (MIM) capacitors after constant voltage stress induction. The use of a high-work-function Ni top electrode improves not only the leakage current, and temperature- and voltage-coefficients of capacitance, but also the long-term capacitance variation after stress induction.
A coupled-simulation-and-optimization approach to nanodevice fabrication with minimization of electrical characteristics fluctuation
(2007-11-01)
Li, Yiming
;
Yu, Shao-Ming
;
資訊工程學系
;
電信工程研究所
;
Department of Computer Science
In this paper, a simulation-based optimization methodology for nanoscale complementary metal-oxide-semiconductor (CMOS) device fabrication is advanced. Fluctuation of electrical characteristics is simultaneously considered and minimized in the optimization procedure. Integration of device and process simulation is implemented to evaluate device performances, where the hybrid intelligent approach enables us to extract optimal recipes which are subject to targeted device specification. Production of CMOS devices now enters the technology node of 65 nm; therefore, random-dopant-induced characteristic fluctuation should be minimized when a set of fabrication parameters is suggested. Verification of the optimization methodology is tested and performed for the 65-nm CMOS device. Compared with realistic fabricated and measured data, this approach can achieve the device characteristics; e.g., for the explored 65-nm n-type MOS field effect transistor, the on-state current > 0.35 mA/mu m, the off-state current < 1.5e - 11 A/mu m, and the threshold voltage = 0.43 V. Meanwhile, it reduces the threshold voltage fluctuation (sigma(vth) similar to 0.017 V). This approach provides an alternative to accelerate the tuning of process parameters and benefits manufacturing of nanoscale CMOS devices.
Method for virtual bass synthesis
(2007-11-01)
Bai, Mingsian R.
;
Tseng, Wen-Liang
;
Lin, Wan-Chi
This invention relates to a method for virtual bass synthesis. The low frequency signal is attained by applying a low pass filter to the original. In order to reduce the operations, process of down sampling the low frequency signal, moving the low frequency signal to a series of harmonics whose frequencies are integral times as large as the frequency of low frequency signals, and then up sampling them are provided. By means of psycho-acoustic theory, the weights of harmonics are attained and applied to the harmonics. Finally the weighted harmonics are combined to produce the bass signal. As the result, the virtual bass effect which is almost the same as the low frequency of the original audio signal can be accomplished. Because the harmonic signals are high frequency ones, the virtual effect can be made in the panel speakers or ordinary low-end speakers.
A multi-criterion interaction-oriented model with proportional rule for designing supply chain networks
(2007-11-01)
Che, Z. H.
;
Wang, H. S.
;
Sha, D. Y.
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
Supply chain management has offered a way to improve the industrial environment becomes more competitive. While, the commonly seen methodologies may be effective in solving the production-distribution problem only from supplier- or customer-oriented consideration, those cannot present the interactive relationship between upstream and downstream enterprises. In the competitive semiconductor industry environment, considering the viewpoints of the supplier and consumer simultaneously is particularly required, because multiple manufacturing and demanding steps are performed at separate situations, concurrently. In this paper, we propose an interaction-oriented approach, which bases on the analytic hierarchy process (AHP) methodology and proportional rule, to solve the semiconductor distribution problem with multiple quantitative and qualitative criteria. The developed approach gives an expected satisfaction for the all participators of the whole chain while the cooperative information is shared perfectly and effectively. Analysis results demonstrate the proposed methodology is efficient and effective through a real world case study. (c) 2006 Elsevier Ltd. All rights reserved.
The identification of positive clones in a general inhibitor model
(2007-11-01)
Hwang, F. K.
;
Chang, F. H.
;
應用數學系
;
Department of Applied Mathematics
In using pooling designs to identify clones containing a specific subsequence called positive clones, sometimes there exist nonpositive clones which can cancel the effect of positive clones. Various models have been studied which differ in the power of cancellation. Although the various models pose interesting mathematical problems, and ingenious constructions of pooling designs have been proposed, in practice we rarely are sure about the true model and thus about which pooling design to use. In this paper we give a pooling design which fits all inhibitor models, and does not use more tests than in the more specific models. In particular, we obtain a I-round pooling design for the k-inhibitor model for which only sequential designs are currently known. (c) 2007 Elsevier Inc. All rights reserved.
手指指向偵測系統及方法
(2007-11-01)
黃仲陵
;
傅智銘
;
簡敬宇
本發明係提供一種手指指向偵測系統及方法，其係以數台影像擷取裝置擷取使用者之數張手部影像，並以一處理器對擷取之數張手部影像進行影像處理求出數條手指指向線，利用座標轉換程式轉換出手指指向線於指向平面上的投影線，最後計算數條投影線之交點，即為使用者手指指向之目標點。本發明不需使用任何定位手套或標記手套即可偵測出使用者指向一平面上之任意目標點，具有高辨析度及高準確率，且可應用於簡報系統，作為取代雷射筆或滑鼠之人機介面。
Multiobjective planning of surface water resources by multiobjective genetic algorithm with constrained differential dynamic programming
(2007-11-01)
Yang, Chao-Chung
;
Chang, Liang-Cheng
;
Yeh, Chao-Hsien
;
Chen, Chang-Shian
;
土木工程學系
Owing to the conflict encountered between the two objectives of fixed cost in reservoir installation and operating cost in time-varying water deficit, multiobjective planning of surface water resources is a difficult job. Instead of combining these two objectives into just one objective using the weighting factor approach, this investigation proposes a novel method by integrating a multiobjective genetic algorithm (MOGA) with constrained differential dynamic programming (CDDP). A MOGA is employed to generate the various combinations of reservoir capacity and estimate the noninferior solution set. However, applying this algorithm to solve the dynamics of the operating cost, the number of variables increasing with time will dramatically increase the use of computational resources. Consequently, the CDDP is herein adopted to distribute optimal releases among reservoirs to satisfy water demand as much as possible. Next, the effectiveness of the proposed methodology is verified by solving a multiobjective planning problem of surface water in southern Taiwan. This real application demonstrates that MOGA can be linked with CDDP to resolve a complex water resources problem. Additionally, the ability of MOGA on addressing multiple objectives simultaneously without converting to a weighted objective function provides the opportunity for significant advancement in multiobjective optimization. Finally, this investigation also proposes three suitable strategies of reservoir construction to decision makers With budget concerns through the analysis of all noninferior solutions.
Distributed clustering algorithms for data-gathering in wireless mobile sensor networks
(2007-11-01)
Liu, Chuan-Ming
;
Lee, Chuan-Hsiu
;
Wang, Li-Chun
;
交大名義發表
;
National Chiao Tung University
One critical issue in wireless sensor networks is how to gather sensed information in an energy-efficient way since the energy is a scarce resource in a sensor node. Cluster-based architecture is an effective architecture for data-gathering in wireless sensor networks. However, in a mobile environment, the dynamic topology poses the challenge to design an energy-efficient data-gathering protocol. In this paper, we consider the cluster-based architecture and provide distributed clustering algorithms for mobile sensor nodes which minimize the energy dissipation for data-gathering in a wireless mobile sensor network. There are two steps in the clustering algorithm: cluster-head election step and cluster formation step. We first propose two distributed algorithms for cluster-head election. Then, by considering the impact of node mobility, we provide a mechanism to have a sensor node select a proper cluster-head to join for cluster formation. Our clustering algorithms will achieve the following three objectives: (1) there is at least one cluster-head elected, (2) the number of cluster-heads generated is uniform, and (3) all the generated clusters have the same cluster size. Last, we validate our algorithms through an extensive experimental analysis with Random Walk Mobility (RWM) model, Random Direction Mobility (RDM) model, and a Simple Mobility (SM) model as well as present our findings. (C) 2007 Elsevier Inc. All rights reserved.
Glass transition temperatures of epoxy modified with pendent nano-organic rigid-rod compounds
(2007-11-01)
Lin, S. P.
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Han, J. L.
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Chen, R. Z.
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Yeh, J. T.
;
Chang, F. C.
Pendent nanoscale organic rigid-rod compounds are molecular fiber-like materials that can be used to reinforce the polymer matrix. In this study, 4,4'-diphenylmethane diisocyanate (MDI) was used to covalently connect a number of organic rigid-rod compounds [4'-hydroxyphenyl-4-hydroxy-benzoate (HPHB), phenyl 4-hydroxybenzoate (HPB), 4,4'-isopropylidenediphenol (BSPA), and 2-naphthol (NPT)] to the secondary hydroxyl groups of the epoxy resin. These reactions were monitored using Fourier transform infrared (FTIR) spectroscopy; the products were characterized using nuclear magnetic resonance (NMR) spectroscopy. The glass transition temperatures of the organic rigid-rod compounds modified epoxy resins were investigated through differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Thermogravimetric analysis (TGA) was used to detect the values of Td and the thermal stabilities of the polymers.
The impact of fabrication errors on a flat-top grating-based planar waveguide demultiplexer
(2007-11-01)
Lin, Chun-Ting
;
Huang, Yang-Tung
;
Huang, Jung-Yaw
;
電子工程學系及電子研究所
;
光電工程學系
The spectral performance of a demultiplexer is significantly affected by the phase and amplitude errors due to fabrication errors. We estimate the impact of fabrication errors on a flat-top grating-based planar waveguide demultiplexer using a design example. Simulation results show that the photomask resolution resulting in a phase error should be lower than 40 nm when a crosstalk criterion of -30 dB is given. The impact of amplitude errors is not distinct until the reduced amount of the facet width is greater than 0.5 mu m and the grating side-wall angle offset from the vertical is larger than 1 degrees.
Local structure formation in alkyl-imidazolium-based ionic liquids as revealed by linear and nonlinear Raman spectroscopy
(2007-11-01)
Iwata, Koichi
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Okajima, Hajime
;
Saha, Satyen
;
Hamaguchi, Hiro-O
;
應用化學系
We show several pieces of Raman spectroscopic evidence that are indicative of local structure formation in imidazolium-based ionic liquids. Low-frequency Raman spectra of C(n)mimX, where C(n)mim stands for 1-alkyl(CnH2n+1)-3-methylimidazolium cation and X represents the anion, exhibit broad bands assignable to collective modes of local structures. Spatial distributions of coherent anti-Stokes Raman scattering (CARS) signals from C(n)mim[PF(6)l are consistent with local structures whose size increases with increasing n. Picosecond Raman spectra of S, trans-stilbene as a "picosecond Raman thermometer" show microscopic thermal inhomogeneity ascribable to local structure formation in C(2)mimTf(2)N and C(4)mimTf(2)N. We also describe two novel phenomena that we believe are relevant to extraordinary nanoenvironments generated by local structures in a magnetic ionic liquid C(4)mim[FeCl4].
Optimal control of an M/G/1/K queueing system with combined F policy and startup time
(2007-11-01)
Wang, K.-H.
;
Kuo, C.-C.
;
Pearn, W. L.
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
We investigate the optimal management problem of an M/G/1/K queueing system with combined F policy and an exponential startup time. The F policy queueing problem investigates the most common issue of controlling the arrival to a queueing system. We present a recursive method, using the supplementary variable technique and treating the supplementary variable as the remaining service time, to obtain the steady state probability distribution of the number of customers in the system. The method is illustrated analytically for exponential service time distribution. A cost model is established to determine the optimal management F policy at minimum cost. We use an efficient Maple computer program to calculate the optimal value of F and some system performance measures. Sensitivity analysis is also investigated.
A quasi-planar thin film field emission diode
(2007-11-01)
Lin, Kao-Chao
;
Juan, Chuan-Ping
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Lai, Rui-Ling
;
Chen, Hsia-Wei
;
Syu, Yu-Ying
A novel quasi-planar thin-film field emitter is fabricated by thin-film deposition and wet etching processes. The spacing between the emitters and collectors could be well controlled on the basis of the thicknesses of Cr thin films, which create submicron gaps. A forming process increases emitter surface roughness and results in a higher field enhancement factor, which shows better field emission characteristics. The turn-on voltage (at which the current level is 100 nA) of the device with a Cr thin film thickness of 300 nm is as low as 12 V, and the current fluctuation in I hour test at a driving voltage of 20 V represents a variation from -86 to +114%.
Design and implementation of a SIP-based mobile and vehicular wireless network with push mechanism
(2007-11-01)
Tseng, Yu-Chee
;
Chen, Jen-Jee
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Cheng, Yu-Li
;
資訊工程學系
;
Department of Computer Science
As portable devices are gaining more popularity, maintaining Internet connectivity anytime and anywhere becomes critical, particularly for mobile and vehicular networks. Network mobility (NEMO) and Internet Protocol mobility are gaining more and more importance. In this paper, we develop a Session Initiation Protocol (SIP)-based mobile network architecture to support NEMO for vehicular applications. We propose to form a mobile ad hoc network (MANET) by the mobile hosts (MHs) inside a vehicle or a cluster of vehicles. The MANET is connected to the outside world via a SIP-based Mobile Network Gateway (SIP-MNG), which is equipped with one or multiple external wireless interfaces and some internal IEEE 802.11 interfaces. The external interfaces of the SIP-MNG support Internet connectivity by aggregating user traffic to and from the Internet. In addition, exploiting the session information carried by SIP signaling, the SIP-MNG supports resource management and call admission control for the MHs. However, wireless access incurs charges, power consumption, and overhead of mobility management. So, it is desirable to allow the SIP-MNG to disconnect its external interfaces when necessary. To guarantee that users inside the mobile network will not lose any incoming request, we propose a push mechanism through short message service to wake up these wireless interfaces in an on-demand manner. We show the detailed signaling to support such a mechanism. The proposed system is fully compatible with existing SIP standards. Our real prototyping experience and some experimental results are also reported.
Novel coexisted sol-gel derived poly-Si-oxide-nitride-oxide-silicon type memory
(2007-11-01)
You, Hsin-Chiang
;
Wu, Chi-Chang
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Ko, Fu-Hsiang
;
Lei, Tan-Fu
;
Yang, Wen-Luh
The authors use a very simple sol-gel spin coating method at 900 degrees C and 1 min rapid thermal annealing to fabricate three different poly-Si-oxide-nitride-oxide-silicon-type flash memories. The memory windows estimated from the curve of drain current versus applied gate voltage are 3, 3.3, and 4 V for (i) HfO2 thin film, (ii) hafnium silicate nanocrystal, and (iii) coexisted hafnium silicate and zirconium silicate nanocrystal memory, respectively. Together with the measurement from gate disturbance and drain disturbance on these fabricated devices, the coexisted nanocrystal devices exhibit better reliability than both the thin film type memory and single nanocrystal type memory. (C) 2007 American Vacuum Society.
An emergency logistics distribution approach for quick response to urgent relief demand in disasters
(2007-11-01)
Sheu, Jiuh-Biing
;
運輸與物流管理系註：原交通所+運管所
;
Department of Transportation and Logistics Management
Quick response to the urgent relief needs right after natural disasters through efficient emergency logistics distribution is vital to the alleviation of disaster impact in the affected areas, which remains challenging in the field of logistics and related study areas. This paper presents a hybrid fuzzy clustering-optimization approach to the operation of emergency logistics co-distribution responding to the urgent relief demands in the crucial rescue period. Based on a proposed three-layer emergency logistics co-distribution conceptual framework, the proposed methodology involves two recursive mechanisms: (1) disaster-affected area grouping, and (2) relief co-distribution. Numerical studies with a real large-scale earthquake disaster occurring in Taiwan are conducted, and the corresponding results indicate the applicability of the proposed method and its potential advantages. We hope that this study can not only make the proposed emergency logistics system available with more benefits to the development of emergency logistics systems for the urgent needs of disaster areas around the world but also stimulate more excellent researches concerning emergency logistics management. (C) 2007 Elsevier Ltd. All rights reserved.
Comparison among three analytical methods for knowledge communities group-decision analysis
(2007-11-01)
Chu, Mei-Tai
;
Shyu, Joseph
;
Tzeng, Gwo-Hshiung
;
Khosla, Rajiv
;
科技管理研究所
Knowledge management can greatly facilitate an organization's learning via strategic insight. Assessing the achievements of knowledge communities (KC) includes both a theoretical basis and practical aspect; however, a cautionary word is in order, because using improper measurements will increase complexity and reduce applicability. Group decision-making, the essence of knowledge communities, lets one considers multi-dimensional problems for the decision-maker, sets priorities for each decision factor, and assesses rankings for all alternatives. The purpose of this study is to establish the objective and measurable patterns to obtain anticipated achievements of KC through conducting a group-decision comparison. The three multiple-criteria decision-making methods we used, simple average weight (SAW), "Technique for Order Preference by Similarity to an Ideal Solution" (TOPSIS) and "VlseKriterijumska Optimizacija I Kompromisno Resenje" (VIKOR), are based on an aggregating function representing "closeness to the ideal point". The TOPSIS and VIKOR methods were used to highlight our innovative idea, academic analysis, and practical appliance value. Simple average weight (SAW) is known to be a common method to get the preliminary outcome. Our study provides a comparison analysis of the above-three methods. An empirical case is illustrated to demonstrate the overall KC achievements, showing their similarities and differences to achieve group decisions. Our results showed that TOPSIS and simple average weight (SAW) had identical rankings overall, but TOPSIS had better distinguishing capability. TOPSIS and VIKOR had almost the same success setting priorities by weight. However, VIKOR produced different rankings than those from TOPSIS and SAW, and VIKOR also made it easy to choose appropriate strategies. Both the TOPSIS and VIKOR methods are suitable for assessing similar problems, provide excellent results close to reality, and grant superior analysis. (c) 2006 Elsevier Ltd. All rights reserved.
Structural evolution of silicon oxide nanowires via head-growth solid-liquid-solid process
(2007-11-01)
Hsu, Cheng-Hang
;
Chan, Shih-Yu
;
Chen, Chia-Fu
;
材料科學與工程學系
;
Department of Materials Science and Engineering
In this paper, we propose a growth mechanism for silicon oxide nanowires (SiONWs) as a unique solid-liquid-solid process. SiONWs were synthesized in a furnace at 1000 degrees C and cooled at a high rate. Nickel and gold were introduced as catalysts to dissolve and precipitate the silicon oxide originally prepared by wet oxidation. The ratio of nickel to gold determined the precipitation rate and different "octopus-like" structures were formed. At a specific cooling rate, composition and amount of a catalyst, aligned silicon oxide nanowires with unattached ends were obtained.
A new approach for constructing the concept map
(2007-11-01)
Tseng, Shian-Shyong
;
Sue, Pei-Chi
;
Su, Jun-Ming
;
Weng, Jul-Feng
;
Tsai, Wen-Nung
In recent years, e-learning system has become more and more popular and many adaptive learning environments have been proposed to offer learners customized courses in accordance with their aptitudes and learning results. For achieving the adaptive learning, a predefined concept map of a course is often used to provide adaptive learning guidance for learners. However, it is difficult and time consuming to create the concept map of a course. Thus, how to automatically create a concept map of a course becomes an interesting issue. In this paper, we propose a Two-Phase Concept Map Construction (TP-CMC) approach to automatically construct the concept map by learners' historical testing records. Phase 1 is used to preprocess the testing records; i.e., transform the numeric grade data, refine the testing records, and mine the association rules from input data. Phase 2 is used to transform the mined association rules into prerequisite relationships among learning concepts for creating the concept map. Therefore, in Phase 1, we apply Fuzzy Set Theory to transform the numeric testing records of learners into symbolic data, apply Education Theory to further refine it, and apply Data Mining approach to find its grade fuzzy association rules. Then, in Phase 2, based upon our observation in real learning situation, we use multiple rule types to further analyze the mined rules and then propose a heuristic algorithm to automatically construct the concept map. Finally, the Redundancy and Circularity of the concept map constructed are also discussed. Moreover, we also develop a prototype system of TP-CMC and then use the real testing records of students in junior high school to evaluate the results. The experimental results show that our proposed approach is workable. (C) 2005 Elsevier Ltd. All rights reserved.
私有電話網路與公眾電話網路間電話繞徑的方法與裝置
(2007-11-01)
張明峰
;
林一平
;
梁慶豐
一種電話繞徑的方法與裝置，係實施於銜接一公眾電話網路(PSTN)與一私有電話網路(PTN)之間的一界面裝置，包括交換機、總機系統、網路交換機、媒體閘道器等裝置。主要是建立、維護與使用一回電路徑表，經由搜尋此回電路徑表，來達成PSTN用戶得以一階段撥號方式直接回撥給PTN用戶。一階段撥號機制的運作程序包括銜接PTN電話至PSTN、銜接PSTN電話至PTN、和插入回電標籤於回電路徑表。回電路徑表由回電標籤所組成，每一筆回電標籤至少包含三個欄位，PTN發話者識別碼、PSTN受話者電話號碼、和外線電話號碼。