Browsing by Issue Date, starting with "2012-02-06"

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交大e-News第111期
(2012-02-06)
Secretariat
;
國立交通大學秘書室
Phase structure of the Kerr-AdS black hole
(2012-02-06)
Tsai, Yu-Dai
;
Wu, X. N.
;
Yang, Yi
;
電子物理學系
;
Department of Electrophysics
We study the critical phenomena of Kerr-AdS black hole. Phase structures are observed at different temperatures, T-L, T-c1 and T-c2 with various features. We discuss the thermal stability considering the isothermal compressibility and how phase transitions related to each other. The asymptotic value of the angular momentum also has an implication on separating stable and unstable part. Near critical temperature T-c1, the order parameter is determined to calculate the critical exponents. All the critical exponents (alpha, beta, gamma, delta) = (0, 1/2, 1, 3) are identical to that of mean field systems. We plot the phase diagram near this critical point, and discuss the scaling symmetry of the free energy.
Electrically driven nanopyramid green light emitting diode
(2012-02-06)
Chang, S. -P.
;
Chen, Y. -C.
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Huang, J. -K.
;
Cheng, Y. -J.
;
Chang, J. -R.
An electrically driven nanopyramid green light emitting diode (LED) was demonstrated. The nanopyramid arrays were fabricated from a GaN substrate by patterned nanopillar etch, pillar side wall passivation, and epitaxial regrowth. Multiple quantum wells were selectively grown on the facets of the nanopyramids. The fabricated LED emits green wavelength under electrical injection. The emission exhibits a less carrier density dependent wavelength shift and higher internal quantum efficiency as compared with a reference c-plane sample at the same wavelength. It shows a promising potential for using nanopyramid in high In content LED applications. (C) 2012 American Institute of Physics. [doi:10.1063/1.3681363]
Intruder detection system and method
(2012-02-07)
Song Kai-Tai
;
Lin Chia-Hao
;
Lin Chih-Sheng
;
Yang Su-Hen
This invention is an intruder detection system which integrates wireless sensor network and security robots. Multiple ZigBee wireless sensor modules installed in the environment can detect intruders and abnormal conditions with various sensors, and transmit alert to the monitoring center and security robot via the wireless mesh network. The robot can navigate in the environment autonomously and approach to a target place using its localization system. If any possible intruder is detected, the robot can approach to that location, and transmit images to the mobile devices of the securities and users, in order to determine the exact situation in real time.
Device for accurately measuring amplifier's open-loop gain with digital stimuli
(2012-02-07)
Hong Hao-Chiao
A device capable of receiving one or more digital stimulus signals and accurately measuring an open-loop gain of an amplifier comprises: a digital charge converter (DCC), a charge integrator, an A/D converter, a control logic circuit and an arithmetic logic unit (ALU). The DCC and the charge integrator are composed of a plurality of switches, one or more sampling capacitor, at least one integrating capacitor and an operational amplifier under test (OPAUT) with a single-ended output or differential-ended outputs. The DCC, the charge integrator, and the A/D converter are controlled by control signals generated by the logic control circuit and can be reconfigured as a first-order Sigma-Delta modulator capable of receiving at least one of the digital input stimulus signals. The ALU calculates the open-loop gain of the OPAUT with single-ended output or differential-ended outputs according to the digital stimulus signals and the digital output of the first-order Sigma-Delta modulator.
LIQUID CRYSTAL LENS AND MANUFACTURING METHOD THEREOF
(2012-02-09)
LIAO LIN-YAO
;
HUANG YI-PAI
;
LIN YU-MIN
;
SHIEH HAN-PING D.
The present invention discloses a liquid crystal lens and a manufacturing method thereof. At least one first electrode is disposed on a first substrate, a first alignment layer is disposed on the first electrode, a liquid crystal layer is disposed on the first alignment layer, a second alignment layer is disposed on the liquid crystal layer, an electric field uniformization layer is disposed on the second alignment layer, at least one second electrode and at least one third electrode are disposed on the electric field uniformization layer, and the second electrode is arranged around the third electrode. A second substrate is disposed on the second electrode and the third electrode. The third electrode which matches up with the second electrode produces an electric field gradient and the liquid crystal layer is affected uniformly by the electric field uniformization layer so as to achieve rapid focus purpose by the liquid crystal.
A T3 and T7 Recombinant Phage Acquires Efficient Adsorption and a Broader Host Range
(2012-02-09)
Lin, Tiao-Yin
;
Lo, Yi-Haw
;
Tseng, Pin-Wei
;
Chang, Shun-Fu
;
Lin, Yann-Tsyr
It is usually thought that bacteriophage T7 is female specific, while phage T3 can propagate on male and female Escherichia coli. We found that the growth patterns of phages T7M and T3 do not match the above characteristics, instead showing strain dependent male exclusion. Furthermore, a T3/7 hybrid phage exhibits a broader host range relative to that of T3, T7, as well as T7M, and is able to overcome the male exclusion. The T7M sequence closely resembles that of T3. T3/7 is essentially T3 based, but a DNA fragment containing part of the tail fiber gene 17 is replaced by the T7 sequence. T3 displays inferior adsorption to strains tested herein compared to T7. The T3 and T7 recombinant phage carries altered tail fibers and acquires better adsorption efficiency than T3. How phages T3 and T7 recombine was previously unclear. This study is the first to show that recombination can occur accurately within only 8 base-pair homology, where four-way junction structures are identified. Genomic recombination models based on endonuclease I cleavages at equivalent and nonequivalent sites followed by strand annealing are proposed. Retention of pseudo-palindromes can increase recombination frequency for reviving under stress.
FLEXIBLE MICRO-SYSTEM AND FABRICATION METHOD THEREOF
(2012-02-09)
CHAO TZU-YUAN
;
LIANG CHIA-WEI
;
CHENG YU-TING
A fabrication method for integrating chip(s) onto a flexible substrate in forming a flexible micro-system. The method includes a low-temperature flip-chip and a wafer-level fabrication process. Using the low-temperature flip-chip technique, the chip is bonded metallically onto the flexible substrate. To separate the flexible substrate from the substrate, etching is used to remove the sacrificial layer underneath the flexible substrate. The instant disclosure applies standardized micro-fabrication process for integrating chip(s) onto the flexible substrate. Without using special materials or fabrication procedures, the instant disclosure offers a cost-effective fabrication method for flexible micro-systems.
III-V METAL-OXIDE-SEMICONDUCTOR DEVICE
(2012-02-09)
CHANG Edward Yi
;
LIN Yueh-Chin
A barrier layer, hafnium oxide layer, between a III-V semiconductor layer and an lanthanum oxide layer is used to prevent interaction between the III-V semiconductor layer and the lanthanum oxide layer. Meanwhile, the high dielectric constant of the lanthanum oxide can be used to increase the capacitance of the semiconductor device.
VARIATION-TOLERANT WORD-LINE UNDER-DRIVE SCHEME FOR RANDOM ACCESS MEMORY
(2012-02-09)
Chuang Ching-Te
;
Lin Yi-Wei
;
Chen Chia-Cheng
;
Shih Wei-Chiang
A Random Access Memory (RAM) is provided. The RAM includes a plurality of word-line drivers, at least a first tracking transistor and a second tracking transistor. Each word-line driver has an input node receiving a decoding signal, a power node receiving an operation voltage and a driving node driving a word-line. In an embodiment, the first tracking transistor has two channel terminal nodes respectively coupled to the driving node of one of the word-line driver and a channel terminal node of the second tracking transistor; wherein the first tracking transistor has electronic characteristics tracking those of a driving transistor of word-line driver, and the second tracking transistor has electronic characteristics tracking those of pass-gate transistor(s) in each cell of the RAM.
FUEL CELL, PLATE HAVING THROUGH-PLANE CONDUCTIVITY, AND MANUFACTURING METHOD THEREOF
(2012-02-09)
HSU FU-MING
;
CHEN JEN-HAO
A fuel cell, a plate having through-plane conductivity and a manufacturing method of the plate are disclosed. The plate having through-plane conductivity includes a substrate and a plurality of linear conductors. The linear conductors are respectively coated with a metal material, and are oriented by a magnetic field to arrange in the substrate with an extending direction perpendicular to a plane surface of the substrate. The substrate is made of an epoxy resin material, the linear conductors are carbon fibers, and the metal material is a magnetic material, such as iron, cobalt or nickel. The fuel cell includes bipolar plates that are respectively made of the above-described plate having through-plane conductivity.
Magnetotransport at Domain Walls in BiFeO3
(2012-02-09)
He, Q.
;
Yeh, C-H.
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Yang, J-C.
;
Singh-Bhalla, G.
;
Liang, C-W.
Domain walls in multiferroics can exhibit intriguing behaviors that are significantly different from the bulk of the material. We investigate strong magnetoresistance in domain walls of the model multiferroic BiFeO3 by probing ordered arrays of 109 degrees domain walls with temperature-and magnetic-field-dependent transport. We observe temperature-dependent variations in the transport mechanism and magnetoresistances as large as 60%. These results suggest that by locally breaking the symmetry of a material, such as at domain walls and structural interfaces, one can induce emergent behavior with properties that deviate significantly from the bulk.
光検出装置構造
(2012-02-10)
孟心飛
;
洪勝富
;
趙宇強
電刺激控制裝置
(2012-02-11)
蔡德明
;
徐建華
本發明提出一種使用多個獨立電源電極來控制電刺激系統以增進刺激區域解析度的新裝置及方法。該裝置中對應電極組包含至少三個電極，且其中有二個相鄰電極具有相同極性電源，用以控制整合刺激訊號的位置，而其他電極則是相反極性電源，用以平衡總電源量及縮減刺激區域。該方法至少包含下列步驟：接收一目標刺激位置及大小及產生至少一個控制參數來調整該對應電極的輸入電源值以得到符合該目標刺激位置及大小的整合刺激訊號。
Selecting detection wavelength of resonant cavity-enhanced photodetectors by guided-mode resonance reflectors
(2012-02-13)
Lai, Kuo-Wei
;
Lee, Yi-Shan
;
Fu, Ying-Jhe
;
Lin, Sheng-Di
;
電子工程學系及電子研究所
We propose and demonstrate a novel device structure of resonant cavity-enhanced photodetector (RCE-PD). The new RCE-PD structure consists of a bottom distributed Bragg reflector (DBR), a cavity with InGaAs multiple quantum wells (MQWs) for light absorption and a top mirror of sub-wavelength grating. By changing the fill factor of the 2-D grating, the effective cavity length of RCE-PDs can be varied so the resonant wavelength can be selected post growth. Accordingly, we can fabricate an array of PDs on a single chip, on which every PD aims for a specific wavelength. (C) 2012 Optical Society of America
Temperature-dependent decay dynamics in highly mismatched ZnSe1-xTex alloy
(2012-02-13)
Lin, Yan-Cheng
;
Jiang, Wei-Shi
;
Chou, Wu-Ching
;
Chen, Wei-Kuo
;
Chang, Wen-Hao
This study investigates the temperature-dependent decay dynamics in highly mismatched ZnSe0.950Te0.050 alloy using photoluminescence (PL) and time-resolved PL spectroscopy. The PL peak energy exhibits a V-shaped dependence on temperature (10-300 K), indicating strong carrier localization. Kohlrausch's stretched exponential law, in which the deduced stretching exponent beta is highly consistent with the V-shaped PL peak shift, closely corresponds to the complex decay curves over a wide temperature range. Additionally, the PL lifetime tau initially increases and then monotonically declines as the temperature increases. These findings agree excellently with the low electron-hole binding energy upon thermal ionization of weakly bound electrons. (C) 2012 American Institute of Physics. [doi:10.1063/1.3687187]
Low threshold current and widely tunable external cavity lasers with chirped multilayer InAs/InGaAs/GaAs quantum-dot structure
(2012-02-13)
Lin, Gray
;
Su, Pei-Yin
;
Cheng, Hsu-Chieh
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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
Low threshold and widely tunable InAs/GaAs quantum-dot lasers are implemented with grating-coupled external-cavity arrangement. Throughout the tuning range of 130 nm, from 1160 to 1290 nm, the threshold current density is not more than 0.9 kA/cm(2) and no noticeable threshold jump is observed. For a shorter-cavity device, the injection current is kept at a record low value of 90 mA but the tuning range is further extended to 150 nm, from 1143 to 1293 nm. The effect of cavity length on the tuning characteristics is discussed and the strategy for design and optimization of multilayer quantum-dot structure is also proposed. (C) 2012 Optical Society of America
Design of distributed amplify-and-forward relay networks for multi-input multi-output transmission
(2012-02-14)
Wu, C-J
;
Lin, D. W.
;
Sang, T-H
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Relays can potentially enhance the transmission performance of multi-input multi-output (MIMO) systems. A parallel single-antenna relay network has additional advantages in flexibility, diversity and cost, but also poses significant design problems because the absence of inter-antenna connections over different relays makes the underlying mathematical problems much more difficult to solve. In this study, the authors consider the design of parallel amplify-and-forward relay networks. More specifically, the authors consider the design of relay gains to maximise the system capacity. As no closed-form analytic solution can be found, the authors first develop an iterative algorithm to find a locally optimal solution. Since algorithmic optimisation provides little insight into the analytical properties of the solution, they also attempt analytical solutions for several asymptotic noise conditions. It turns out that the solutions involve some methods to select the optimal subsets of relays for signal forwarding. The authors analyse the resulting capacity outage diversity orders and confirm the analysis with simulation results.
Method for identification of traffic lane boundary
(2012-02-14)
Jou Yow-Jen
;
Cho Hsun-Jung
;
Chen Yu-Kuang
;
Huang Heng
;
Hsu Chia-Chun
The invention provides a method for identification of traffic lane boundary. Firstly the microwave signal is received, and the noise reduction is treated for the microwave signal. Then the frequency domain information is employed to calculate the legal set of closed interval, in order to form the frequency span information. Finally, the probability density function model is employed to calculate the frequency span information in order to identify the traffic lane boundary.
PHPIT and fabrication thereof
(2012-02-14)
Wei Kung-Hwa
;
Chang Yao-Te
The present invention provides PHPIT and fabrication thereof. PHPIT has a side-chain-tethered with hexylphenanthrenyl-imidazole polythiophene. The visible light absorption of the PHPIT/PCBM blend is enhanced by the presence of the electron-withdrawing hexylphenanthrenyl-imidazole. The PHPIT/PCBM blend experienced more-balanced electron and hole mobilities and solvability.