Browsing by Issue Date, starting with "2005-06-01"

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Perceived fairness of pricing on the Internet
(2005-06-01)
Huang, JH
;
Chang, CT
;
Chen, CYH
;
管理科學系
;
經營管理研究所
The perceived fairness of price changes has been a subject of much inquiry in economic and marketing literature. This paper examines consumers' perceptions of the fairness of pricing on the Internet. Fair prices on the Internet, pricing mechanisms, methods of price discrimination and yield management are investigated from a consumer's perspective. Results obtained from 276 questionnaires collected in Taiwan indicate that the Internet prices that equal those in the traditional channels are perceived to be unfair. Respondents considered various pricing mechanisms on the Internet to be fair while many practices of price discrimination and yield management were perceived to be unfair. © 2004 Elsevier B.V. All rights reserved.
Reliability of strained SiGe channel p-channel metal-oxide-semiconductor field-effect transistors with ultra-thin (EOT=3.1nm) N2O-annealed SiN gate dielectric
(2005-06-01)
Chen, CW
;
Chien, CH
;
Chen, YC
;
Hsu, SL
;
Chang, CY
The p-channel metal-oxide-semi conductor field-effect transistor (pMOSFET) with 50-nm-thick Si0.85Ge0.15 channel and in ultra-thin (EOT = 3.1 nm) N2O-annealed SiN gate dielectric has been shown to have well-performing on/off and output characteristics. Several methodologies for the device reliability characterization, such as stress-induced-leakage-current (SILC), drain-avalanche-hot-carrier (DAHC) injection, channel hot-carrier (CHC) injection and negative-bias-temperature-instability (NBTI), have been used and the results were compared. In terms of the long-term degradation, the excellent quality of the N2O-annealed SiN gate dielectric can be firmly obtained because only negligible degradations have been found after stressing no matter which technique was employed. Even so, the experimental results have been compared and we found that the HC degradation is worse than the NBTI degradation and the channel-hot-carrier (CHC) stressing is the worst case for all kinds of reliability testing. Meanwhile, we have also verified that the interface state generation is the dominant mechanism responsible for the HC-induced degradation while the electron trapping dominates the device degradation for the NBTI stressing.
Implementation of wireless network environments supporting inter access point protocol and dual packet filtering
(2005-06-01)
Hwang, LY
;
Chiang, ML
;
Chang, RC
;
資訊工程學系
;
Department of Computer Science
With advances in wireless technologies, future internetworks will include large numbers of mobile hosts roaming across wireless cells. The goal of this paper is to provide a wireless network communication environment, in which mobile hosts can roam among various access points (wireless cells) and across different subnets. For this purpose, we develop methods to implement and integrate the communication mechanisms of Mobile IP and Inter Access Point Protocol (IAPP). For efficient transmission, we also devise a dual packet filtering technique to filter out unnecessary packet transmission, thereby reducing traffic on wireless networks. Such filtering is especially important because of the limited bandwidth of wireless links. Our work can serve as the reference once IAPP has been approved as standard. (c) 2004 Elsevier Inc. All rights reserved.
Improving high-temperature performance in continuous-wave mode InGaAsN/GaAsN ridge waveguide lasers
(2005-06-01)
Chang, YA
;
Kuo, HC
;
Lu, CY
;
Kuo, YK
;
Wang, SC
Continuous-wave (CW) mode operation InGaAsN/GaAsN double-quantum-well lasers with a laser wavelength of 1.295 mu m are demonstrated by metal-organic chemical vapour deposition (MOCVD). With the use of a high-bandgap GaAs0.9P0.1 into the active region before the growth of p-type layers, a room temperature (RT) threshold current of 99 mA and the characteristic temperature (TO) values of 155 K in a temperature range of 25-95 degrees C and 179 K in a temperature range of 25-85 degrees C are obtained from a 4 x 1000 mu m(2) ridge waveguide uncoated laser diode. The To value of the conventional structure without the high-bandgap GaAs0.9P0.1 is 118 K in a temperature range of 25-95 degrees C. High-temperature performance is improved and the results of numerical analysis suggest that it may be attributed to the reduced electronic leakage current.
Spin-flip transport through an interacting quantum dot
(2005-06-01)
Lin, KC
;
Chuu, DS
;
電子物理學系
;
Department of Electrophysics
The spin-flip associated transport based on the Anderson model is studied. It is found that the electrons are scattered due to spin-flip effect via the normal, mixed and Kondo channels. The spin-flip scattering via Kondo channel enhances the Kondo resonance peak and causes a slight blue shift. The conductance is suppressed by the spin-flip scattering. This is attributed to the reason that electrons with energy near Fermi level are scattered by Kondo channel. (c) 2005 Elsevier Ltd. All rights reserved.
一種超薄型平面喇叭之結構及其最佳化設計方法
(2005-06-01)
白明憲
;
呂彥志
本發明係為一種超薄型平面喇叭之結構及其最佳化設計方法，其結構包含一板材、一壓電材料一導電材以及懸邊。最佳化設計方法之模擬系統是以能量法與變分原理為基礎理論並利用有限元素法求解，其中程序同時考慮電能系統、機械系統以及聲場系統空氣之負載效應。再利田口實驗計畫法與基因演算法做結構之最佳化設計，以使得超薄型平面喇叭在較低之共振頻率下仍能維持與高共振頻率時之平均聲壓值相近，以達音質、音量最佳之目的。本創作之特點在於透過喇叭結構之最佳化程序可充分發揮音質喇叭之優點，不僅可以製作成任意平面形狀，大幅提高喇叭之聲功率，而且使用上非常省電有效率，並可改善喇叭在高共振頻率時，聲音太過尖銳之缺點。
A novel process-compatible fluorination technique with electrical characteristic improvements of poly-Si TFTs
(2005-06-01)
Wang, SD
;
Lo, WH
;
Chang, TY
;
Lei, TF
;
電子工程學系及電子研究所
A process-compatible fluorine passivation technique of poly-Si thin-film transistors (TFTs) was demonstrated by employing a novel CF4 plasma treatment. Introducing fluorine atoms into poly-Si films can effectively passivate the trap states near the SiO2/poly-Si interface. With fluorine incorporation, the electrical characteristics of poly-Si TFTs can be significantly improved including a steeper subthreshold slope, smaller threshold voltage, lower leakage current, higher field-effect mobility, and better On/Off current ratio. Furthermore, the CF4 plasma treatment also improves the reliability of poly-Si TFTs with respect to hot-carrier stress, which is due to the formation of strong Si-F bonds.
Intracavity PPLN crystals for ultra-low-voltage laser Q-switching and high-efficiency wavelength conversion
(2005-06-01)
Chen, YH
;
Huang, YC
;
Lin, YY
;
Chen, YE
;
電子物理學系
We report to the best of our knowledge the lowest switching voltage in an electro-optically Q-switched Nd: YVO4 laser by using a 13-mm long, 14-μ m-period PPLN crystal as a Pockels cell. A switching voltage as low as &SIM; 50V in the PPLN crystal was sufficient to hold off the lasing of the Q-switched laser at a pump power more than two times above its continuous-wave threshold. When the PPLN Q-switch was driven by a 100-V voltage at 6.5 kHz, we obtained 0.9-kW laser peak power from this 1-W diode-pumped Nd: YVO4 laser system with 13% output coupling. When the PPLN Pockels cell was cascaded with a 5-cm long, 30-μ m-period PPLN crystal, we produced &SIM; μ J/pulse energy at 1.59 μ m from optical parametric generation inside the actively Q-switched laser.
Guest editorial - Mobile computing and networking
(2005-06-01)
Wei, DSL
;
Naik, K
;
Lin, YB
;
Olariu, S
;
Wang, LC
Thermoelectric effects in superconductors
(2005-06-01)
Kolacek, J
;
Yang, TJ
;
電子物理學系
;
Department of Electrophysics
It is widely believed that temperature gradient does not induce electric field in the superconductor and consequently that thermoelectric effects do not exist, or are negligible in these materials. This statement is correct only as far as effective electric field or gradient of the electrochemical potential is concerned. In normal metals temperature gradient generates effective electric field, which nulls out thermally induced diffusion current. In superconductor the diffusion current of quasiparticles is canceled by a counterflow of supercurrent. Superconducting current induces the true electric field, which can be approximated by gradient of the screened Bernoulli potential. It explains familiar giant thermomagnetic flux observed in superconducting thermocouples. Contactless measurements of thermoelectric effects are suggested.
Applying hexagonal nanostructured zeolite particles for acetone removal
(2005-06-01)
Lin, YC
;
Bai, HL
;
Chang, CL
;
環境工程研究所
;
Institute of Environmental Engineering
This study examines the performance of a new adsorbent, hexagonal nanostructured zeolite particles (HNZP) for acetone adsorption and compares the results with that of commercial mobil synthetic zeolite-5 (ZSM-5) type zeolite. The HNZP is a pure siliceous adsorbent with different values of pore diameter and surface area being adjustable by the manufacturing condition. The results indicate that a slight increase in the average pore diameter (d) of HNZP from 2 to 2.5 nm leads to an increase in the acetone adsorption capacity, although its surface area is decreased, in which case (d = 2.5 nm) the adsorption capacity of fresh HNZP is better than that of ZSM-5 zeolite. Even for the fresh HNZP (d = 2 nm) of which the adsorption capacity is less than that of the ZSM-5 zeolite at relative humidity (RH) of 0%, its adsorption capacity is not deteriorated after repeated regeneration, but the adsorption capacity of regenerated ZSM-5 zeolite decays markedly. Thus, after only one regeneration, the adsorption capacity of HNZP (d = 2 nm) becomes better than that of the ZSM-5 zeolite. The decrease in the adsorption capacity of regenerated ZSM-5 zeolite might be because of its aluminum content that catalyzes the acetone into coke and, thus, blocks the adsorption sites. Furthermore, result on the moisture effect shows that because the pure siliceous HNZP was more hydrophobic than the ZSM-5 zeolite, the acetone adsorption efficiency of fresh HNZP (d = 2 nm) is better than that of ZSM-5 zeolite at RH = 50%.
Java-based component framework for dynamic reconfiguration
(2005-06-01)
Lee, YF
;
Chang, RC
;
資訊工程學系
;
Department of Computer Science
Updating software via the Internet is becoming a necessary feature of contemporary software. However, most software updating processes need to restart the programs or systems after the new software modules are installed. Dynamic reconfiguration is a technique that can deploy new software modules without restarting. This is usually achieved by modifying programming language syntax, language runtime systems or the code that is compiled. In the paper, a Java-based component framework is proposed to support dynamic reconfiguration, which does not need to modify the Java language, the Java virtual machine or the Java bytceode. The component framework has two implementations. The first one is based on the Java language itself; it is slower but can be used on almost every Java virtual machine. The second one is based on both the Java code and native programming interfaces provided by the Java virtual machine; it is much more efficient but is platform-dependent. The component framework is able to replace a single component as well as multiple components. In addition, several kinds of component change are permitted, including data members and component interfaces. To demonstrate the use of the component framework, a dynamically reconfigurable TCP is implemented.
Risk assessment for build-operate-transfer projects: a dynamic multi-objective programming approach
(2005-06-01)
Kang, CC
;
Feng, CM
;
Khan, HA
;
運輸與物流管理系註：原交通所+運管所
;
Department of Transportation and Logistics Management
This study uses a dynamic multi-objective programming approach to establish a risk assessment model, and develops an iterative algorithm for the model solution. The results obtained show that the sum of the interactive utility value could determine whether or not the interactive relationship is characterized by independence among negotiators. In addition, our numerical example shows that the risk measurement model developed can reflect risk assessment made by the negotiation group for certain events, and can analyze interaction characteristics among negotiators. (C) 2003 Elsevier Ltd. All rights reserved.
Design of a power-reduction viterbi decoder for WLAN applications
(2005-06-01)
Lin, CC
;
Shih, YH
;
Chang, HC
;
Lee, CY
;
電子工程學系及電子研究所
In this paper, a 64-state four-bit soft-decision Viterbi decoder with power saving mechanism for high speed wireless local area network applications is presented. Based on path merging and prediction techniques, a survivor memory unit with hierarchical memory design is proposed to reduce memory access operations. It is found that more than 70% memory access can be reduced by taking advantage of locality. Moreover, a low complexity compare-select-add unit is also presented, leading to save 15% area and 14.3% power dissipation as compared to conventional add-compare-select design. A test chip has been designed and implemented in 0.18-mu m standard CMOS process. The test results show that 30 similar to 40% power dissipation can be reduced, and the power efficiency reaches 0.75 mW per Mb/s at 6 Mb/s and 1.26 mW per Mb/s at 54 Mb/s as specified in IEEE 802.11a.
光纖光柵感應地層移動監測管及包含有此光纖光柵感應地層移動監測管的監測系統
(2005-06-01)
黃安斌
;
簡旭君
本發明提拱一種用於感應地層移動之監測系統，包括有：一光纖光柵感應地層移動監測管，係埋入在地層下，且具有一管狀物以及具有複數點光柵之複數光纖；一解析器，其係設置在地表面上，且藉由一光纖而連接至該光纖光柵感應地層移動監測管；以及一電腦，其係設置在地表面上，且藉由一電線而連接至該解析器，其中該等光纖的複數點光柵會根據地層移動來反應出該等光柵所產生之反射光波長變化至該解析器；該解析器會提供該光纖光柵感應地層移動監測管所需之光源，並反應該光纖光柵所產生之反射光波長的變化，最後把該光纖光柵所產生之反射光波長的變化透過該電線傳送至該電腦中；以及該電腦會把來自該解析器中反射光波長的變化分析，以獲得地層移動之大小。
Selecting the number of classes under latent class regression: A factor analytic analogue
(2005-06-01)
Huang, GH
;
統計學研究所
;
Institute of Statistics
Recently, the regression extension of latent class analysis (RLCA) model has received much attention in the field of medical research. The basic RLCA model summarizes shared features of measured multiple indicators as an underlying categorical variable and incorporates the covariate information in modeling both latent class membership and multiple indicators themselves. To reduce complexity and enhance interpretability, one usually fixes the number of classes in a given RLCA. Often, goodness of fit methods comparing various estimated models are used as a criterion to select the number of classes. In this paper, we propose a new method that is based on an analogous method used in factor analysis and does not require repeated fitting. Two ideas with application to many settings other than ours are synthesized in deriving the method: a connection between latent class models and factor analysis, and techniques of covariate marginalization and elimination. A Monte Carlo simulation study is presented to evaluate the behavior of the selection procedure and compare to alternative approaches. Data from a study of how measured visual impairments affect older persons' functioning are used for illustration.
Degradation of low-frequency noise in partially depleted silicon-on-insulator metal oxide semiconductor field-effect transistors by hot-carrier stress
(2005-06-01)
Chen, KM
;
Hu, HH
;
Huang, GW
;
Chang, CY
;
電子工程學系及電子研究所
In this study, we determined the effects of hot-carrier stress on the low-frequency noise characteristics of partially depleted metal-oxide-semi conductor field-effect transistors (MOSFETs) in silicon-on-insulator (SOI) technology. In devices with a floating-body configuration, kink-related excess noise was observed due to the floating-body effect. The level of this excess noise decreased after normal-mode stress, while it was masked by 1/f noise after reverse-mode stress. The effects of stress-generated interface traps on the drain-to-body leakage current and the floating-body effect were also determined and used to explain the noise behavior. Moreover, the stress-induced 1/f noise degradation in floating-body devices and body-contact devices was studied. It was found that the 1/f degradation of body-contact devices is more significant than that of floating-body devices after hot-carrier stress.
On possibility of the tau neutrino astronomy in GeV energies
(2005-06-01)
Athar, H
;
Lee, FF
;
Lin, GL
;
物理研究所
;
Institute of Physics
We discuss the possibility of searching the galactic-plane tau neutrinos in GeV energies.
以邊界聲源表示法為基礎之空間音效混成方法
(2005-06-01)
白明憲
;
歐昆應
一種以邊界聲源表示法為基礎之空間音效混成方法；主要係將密閉空間聲場等效成一個主要聲源以及均勻分布在聲場邊界上的虛擬次要聲源。虛擬次要聲源即是用來模擬聲場的反射以及混響的現象。最後根據這個假設所推導數學模式將符合波動方程式(wave equation)。由這個關係式，利用最小平方法(least–square procedure)來求解反矩陣以得到每個虛擬聲源的強度。所算出來的一組虛擬聲源強度即代表一個特定的聲場所產生的混響效果。在模擬的過程中亦可以設定其聲場的幾何大小，以及與頻率相關的邊界條件如聲場邊界的吸音律。
Raman scattering studies of single-crystal La1-xSrxMnO3
(2005-06-01)
Her, JL
;
Liu, HL
;
Mukovskii, YM
;
Lin, JY
;
Hsu, YY
We present the results of Raman scattering studies of single-crystal La1-xSrxMnO3 (x = 0.05, 0.10, 0.15, 0.20, 0.25, and 0.35) as a function of doping and in the temperature range 10-300 K. The room-temperature Raman spectrum of the x = 0.05 compound displays four phonon bands near similar to 260, 488, 612, and 674 cm(-1). With increasing Sr doping, and a corresponding structural phase transition from an orthorombic to a rhombohedral form, there is a broadening of the linewidths and a decrease in intensities of these phonon modes. 14 When the temperature is lowered, for the x = 0.05 material, two low-frequency phonons associated with the out-of-phase rotation and internal bending of MnO6 octahedra show a noticeable hardening below the canted anti-ferromagnetic transition, which is an evidence for strong spin-phonon coupling. Interestingly, this anomalous behavior disappears in the higher Sr doping level.