Browsing by Issue Date, starting with "2014-10-06"

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交大e-News第172期
(2014-10-06)
Secretariat
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國立交通大學秘書室
OFDM RF power-fading circumvention for long-reach WDM-PON
(2014-10-06)
Chow, C. W.
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Yeh, C. H.
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Sung, J. Y.
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光電工程學系
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光電工程研究所
We propose and demonstrate an orthogonal frequency division multiplexing (OFDM) radio-frequency (RF) power-fading circumvention scheme for long-reach wavelength-division-multiplexed passive-optical-network (LR-WDM-PON); hence the same capacity of 40 Gb/s can be provided to all the optical-networking-units (ONUs) in the LR-WDM-PON. Numerical analysis and proof-of-concept experiment are performed. (C) 2014 Optical Society of America
Mechanism of Back Electron Transfer in an Intermolecular Photoinduced Electron Transfer Reaction: Solvent as a Charge Mediator
(2014-10-06)
Narra, Sudhakar
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Nishimura, Yoshifumi
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Witek, Henryk A.
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Shigeto, Shinsuke
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應用化學系
Back electron transfer (BET) is one of the important processes that govern the decay of generated ion pairs in intermolecular photoinduced electron transfer reactions. Unfortunately, a detailed mechanism of BET reactions remains largely unknown in spite of their importance for the development of molecular photovoltaic structures. Here, we examine the BET reaction of pyrene (Py) and 1,4-dicyanobenzene (DCB) in acetonitrile (ACN) by using time-resolved near-and mid-IR spectroscopy. The Py dimer radical cation (Py-2(center dot+)) and DCB radical anion (DCB center dot-) generated after photoexcitation of Py show asynchronous decay kinetics. To account for this observation, we propose a reaction mechanism that involves electron transfer from DCB center dot- to the solvent and charge recombination between the resulting ACN dimer anion and Py-2(center dot+). The unique role of ACN as a charge mediator revealed herein could have implications for strategies that retard charge recombination in dye-sensitized solar cells.
Electron-electron scattering-induced channel hot electron injection in nanoscale n-channel metal-oxide-semiconductor field-effect-transistors with high-k/metal gate stacks
(2014-10-06)
Tsai, Jyun-Yu
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Chang, Ting-Chang
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Chen, Ching-En
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Ho, Szu-Han
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Liu, Kuan-Ju
This work investigates electron-electron scattering (EES)-induced channel hot electron (CHE) injection in nanoscale n-channel metal-oxide-semiconductor field-effect-transistors (n-MOSFETs) with high-k/metal gate stacks. Many groups have proposed new models (i.e., single-particle and multiple-particle process) to well explain the hot carrier degradation in nanoscale devices and all mechanisms focused on Si-H bond dissociation at the Si/SiO2 interface. However, for high-k dielectric devices, experiment results show that the channel hot carrier trapping in the pre-existing high-k bulk defects is the main degradation mechanism. Therefore, we propose a model of EES-induced CHE injection to illustrate the trapping-dominant mechanism in nanoscale n-MOSFETs with high-k/metal gate stacks. (C) 2014 AIP Publishing LLC.
Static random access memory apparatus and bit-line voltage controller thereof
(2014-10-07)
Chuang Ching-Te
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Lien Nan-Chun
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Liao Wei-Nan
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Chang Chi-Hsin
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Yang Hao-I
A static random access memory apparatus and a bit-line voltage controller includes a controller, a pull-up circuit, a pull-down circuit and a voltage keeping circuit. The controller receives a bank selecting signal and a clock signal, and decides a pull-up time period, a pull-down time period and a voltage keeping time period according to the bank selecting signal and the clock signal. The pull-up circuit pulls up a bit-line power according to a first reference voltage within the pull-up time period. The pull-down circuit pulls down the bit-line power according to a second reference voltage within the pull-down time period. The voltage keeping circuit keeps the bit-line power to equal to an output voltage during the voltage keeping time period. The voltage keeping time period is after the pull-up time period and the pull-down time period.
Enhanced tunnel field effect transistor
(2014-10-07)
Wang Pei-Yu
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Tsui Bing-Yue
An enhanced tunnel field effect transistor includes a substrate, a layer of P-I-N structure, a hetero-material layer, a gate dielectric layer, a gate structure and a spacer, in which the layer of P-I-N structure is disposed on the substrate, the hetero-material layer is disposed on portion of the layer of P-I-N structure, the gate dielectric layer is disposed on the hetero-material layer, the gate structure is disposed the gate dielectric layer and a spacer is disposed on a sidewall of the hetero-material layer, the gate dielectric layer, and the gate structure. The hetero-material layer can increase the tunneling efficiency of the enhanced tunnel field effect transistor to increase the conductor current to improve the enhanced tunnel field effect transistor performance.
Blind ICA detection based on second-order cone programming for MC-CDMA systems
(2014-10-08)
Jen, Chih-Wei
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Jou, Shyh-Jye
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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 multicarrier code division multiple access (MC-CDMA) technique has received considerable interest for its potential application to future wireless communication systems due to its high data rate. A common problem regarding the blind multiuser detectors used in MC-CDMA systems is that they are extremely sensitive to the complex channel environment. Besides, the perturbation of colored noise may negatively affect the performance of the system. In this paper, a new coherent detection method will be proposed, which utilizes the modified fast independent component analysis (FastICA) algorithm, based on approximate negentropy maximization that is subject to the second-order cone programming (SOCP) constraint. The aim of the proposed coherent detection is to provide robustness against small-to-medium channel estimation mismatch (CEM) that may arise from channel frequency response estimation error in the MC-CDMA system, which is modulated by downlink binary phase-shift keying (BPSK) under colored noise. Noncoherent demodulation schemes are preferable to coherent demodulation schemes, as the latter are difficult to implement over time-varying fading channels. Differential phase-shift keying (DPSK) is therefore the natural choice for an alternative modulation scheme. Furthermore, the new blind differential SOCP-based ICA (SOCP-ICA) detection without channel estimation and compensation will be proposed to combat Doppler spread caused by time-varying fading channels in the DPSK-modulated MC-CDMA system under colored noise. In this paper, numerical simulations are used to illustrate the robustness of the proposed blind coherent SOCP-ICA detector against small-to-medium CEM and to emphasize the advantage of the blind differential SOCP-ICA detector in overcoming Doppler spread.
Research of accommodative microfluctuations caused by visual fatigue based on liquid crystal and laser displays
(2014-10-10)
Jeng, Wei-De
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Ouyang, Yuan
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Huang, Ting-Wei
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Duann, Jeng-Ren
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Chiou, Jin-Chern
Different levels of visual fatigue in the human eye depend on different color-formation methods and image quality. This paper uses the high-frequency component of the spectral power of accommodative microfluctuations as a major objective indicator for analyzing the effects of visual fatigue based on various displays, such as color-formation displays and 3D displays. Also, a questionnaire is used as a subjective indicator. The results are that 3D videos cause greater visual fatigue than 2D videos (p < 0.001), the shutter-type 3D display causes visual fatigue more than the polarized type (p = 0.012), the display of the time-sharing method causes greater visual fatigue than the spatial-formation method (p = 0.008), and there is no significance between various light source modules of displays (p = 0.162). In general, people with normal color discrimination have more visual fatigue than those with good color discrimination (p < 0.001). Therefore, this paper uses the high-frequency component of accommodative microfluctuations to evaluate the physiological stress or strain by overexerting the visual system, and can compare the level of visual fatigue between various displays. (C) 2014 Optical Society of America
Simulation and comparison of the illuminance, uniformity, and efficiency of different forms of lighting used in basketball court illumination
(2014-10-10)
Sun, Wen-Shing
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Tien, Chuen-Lin
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Tsuei, Chih-Hsuan
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Pan, Jui-Wen
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光電系統研究所
We simulate and compare the illuminance, uniformity, and efficiency of metal-halide lamps, white LED light sources, and hybrid light box designs combining sunlight and white LED lighting used for indoor basketball court illumination. According to the optical simulation results and our examination of real situations, we find that hybrid light box designs combining sunlight and white LEDs do perform better than either metal-halide lamps or white LED lights. An evaluation of the sunlight concentrator system used in our inverted solar cell shows that the energy consumption of stadium lighting can be reduced significantly. (C) 2014 Optical Society of America
Design and analysis of wearable pupillometer for autonomic neuropathy of diabetic patients
(2014-10-10)
Ko, Mei-Lan
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Chen, Yin-Yuan
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Ouyang, Yuan
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Huang, Ting-Wei
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Tsuen, Bi-Shiou
Diabetes is a familiar disease in modern society. In the early stage of diabetes, symptoms are unobvious, but they usually induce diabetic autonomic neuropathy or, worse, cardiovascular autonomic neuropathy. Pupillometers are effective instruments for observing human pupils. This article presents a novel wearable pupillometer design, without external light artifacts, and an embedded algorithm with blinking elimination, which investigates autonomic neuropathy through recording pupil dynamics triggered by an external sensitive invisible light source. The pupillometer is experimented on 36 healthy subjects and 10 diabetic patients under four different colors (white, red, green, and blue) as well as two different light intensities: 50 and 500 mcd. Ten parameters derived from pupil diameter, pupil response time, and pupil response speed will be evaluated for the healthy subjects and diabetic patients. The results show that three in four parameters related to pupil diameters, one in four related to light intensities, and one in two related to pupil response speed could have significant differences (p < 0.05) between healthy subjects and diabetic patients. These parameters obtain over 85% sensitivity, 83% specificity, and 88% accuracy. The pupillometer is proven reliable, effective, portable, and inexpensive for diagnosing diabetes in an early stage. (C) 2014 Optical Society of America
Noncollinear ferrimagnetic ground state in Ni(NO3)(2)
(2014-10-10)
Volkova, O. S.
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Mazurenko, V. V.
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Solovyev, I. V.
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Deeva, E. B.
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Morozov, I. V.
Both spin-liquid and magnetically ordered phases of both half-integer and integer low-spin quantum magnets are of interest, since the magnetic structures found in the latter case usually have no classical counterparts. Such a magnetic structure was found in a combined experimental and theoretical study of the integer spin system Ni(NO3)(2). Our thermodynamic measurements have revealed a magnetically ordered phase with small spontaneous magnetization at T-C = 5.5 K. The magnetization saturation of about 2 mu(B) at low temperatures corresponds to the high-spin state (S = 1) of Ni2+ ions evidenced in L-2,L-3 edges in x-ray absorption spectroscopy spectra. We show that a consistent description of the available data is possible within a noncollinear umbrella-type ferrimagnetic ground state model for which both intra-and interlayer magnetic interactions should be antiferromagnetic. Such a scenario is suggested by the first-principles and model calculations.
Compact LED projector design with high uniformity and efficiency
(2014-10-10)
Sun, Wen-Shing
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Tien, Chuen-Lin
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Ma, Chao-Hui
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Pan, Jui-Wen
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光電系統研究所
The aim of this study is to design a compact LED projector that is divided into two systems: an illumination system and an imaging optical system. The illumination system consists of an RGB LED light source with a collimator lens group and a mirror with a color filter and a lens array integrator instead of an integrated rod so as to improve the uniformity of the light intensity. By using a new total internal reflection prism and projection lens, the whole optical engine is smaller in size and has a higher contrast ratio for image quality. The imaging optical system consists of a total of eight lenses (six spherical lenses and two aspherical lenses), for a total length of 52 mm; a tolerance analysis is conducted. Optical simulation software is used for the system analysis in order to determine the efficiency and uniformity of the light intensity. In this design, the uniformity of the screen reaches more than 82%, and the efficiency increases by more than 44%. (C) 2014 Optical Society of America
融合人臉辨識及語音辨識之身份辨識系統、其方法及其服務型機器人
(2014-10-11)
宋開泰
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簡碩成
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林昭宇
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陳奕彣
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陳信宏
本發明係揭露一種融合人臉辨識及語音辨識之身份辨識系統、其方法及其服務型機器人。此系統採用人臉辨識及語音辨識兩方的結果經過融合計算後產生最終結果。另外，此系統能藉由信心指數評估人臉辨識及語音辨識兩方辨識結果的可信度，若信心指數超出門檻值更納入融合計算。若只有一方的信心指數超過門檻值就只採納一方的結果做為輸出，如果兩方都超出門檻值則使用融合演算法輸出結果。
移動預測方法
(2014-10-11)
林一平
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皇甫建君
本發明係揭露一種移動預測方法，其係利用在複數基地台所涵蓋之複數相鄰之通訊細胞間移動與通訊之至少一通訊電話，於一預測時段內，對使用通訊電話之人口移動進行預測。首先，擷取在一天中，通訊電話於每一通訊細胞產生之一話務量，與通訊電話在通訊細胞交遞移動所產生之一交遞資訊。接著，計算話務量及交遞資訊，以得到一天內在不同之時段中，人口在通訊細胞間移動之移動機率，及人口在每一通訊細胞涵蓋之區域之一平均停駐時間。最後，依據求得之資料，預測在預測時段之時間終點時，人口出現在每一區域之一出現機率，進而達到人口移動預測。
磁性奈米複合材料及其製造方法及應用
(2014-10-11)
李耀坤
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詹富全
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黃靜萍
本發明之一種磁性奈米複合材料，包括至少一磁性奈米粒子、一修飾層、一配位基團以及一高分子包覆層。修飾層係包括複數矽烷基團，並包覆至少部分磁性奈米粒子，且修飾層具有複數凹部。配位基團係連結於修飾層之凹部。高分子包覆層係連結修飾層。本發明另提供一種磁性奈米複合材料之製造方法以及磁性奈米複合材料應用於蛋白質之純化。
全像式集光元件及其製法
(2014-10-11)
謝美莉
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林尚佑
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許根玉
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林烜輝
數位類比轉換電路及其權重誤差估測與校正方法
(2014-10-11)
洪浩喬
;
王毓賢
生物檢測裝置及檢測方法
(2014-10-11)
林怡欣
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朱為麟
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吳麗卿
本發明係揭露一種生物檢測裝置及檢測方法，係用以檢測三酸甘油酯或高密度膽固醇等生物檢體。此檢測裝置包含基板、電場單元、液晶聚合物薄膜、電源供應器、處理單元及影像感測器。透過控制橫向電場之強度分佈，可使液晶聚合物薄膜表面之液晶分子轉向，以達到薄膜表面親疏水特性的控制，藉以驅動生物檢體移動並觀察運動型態，最後得到此檢體的生理資訊。藉由觀察血清溶液接觸角的改變與運動來得知不同三酸甘油酯及高密度膽固醇濃度。
獨立成分分析處理器
(2014-10-11)
陳秋國
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方偉騏
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李鴻溝
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傅致中
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曾少彥
一種獨立成分分析處理器，係用以對多通道平行信號進行即時獨立成分分析(independent component analysis)之運算，包括接收及儲存該多通道平行信號之輸入記憶體單元、平均與共變異單元、去除該多通道平行信號中的直流成分之中心化單元、進行白化處理之白化單元、及進行獨立成分分析運算之ICA訓練單元和ICA計算單元，俾計算出該多通道平行信號之獨立成分，以分離出信號中的雜訊。據此，藉由本發明之運用，得以實現以低成本及低複雜度之硬體即時進行獨立成分分析運算之功效。
古典音樂　貫穿電影的旋律
(2014-10-12)
陳亞柔
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Department of Communication and Technology
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傳播與科技學系
古典音樂以配樂形式融入現代電影，不但增添場景氣氛，也烘托演員演技，和觀眾產生新的互動，呈現全新風貌。