Browsing by Issue Date, starting with "2009-08-18"

Now showing 1 - 20 of 50076

Structure of high power edge emission laser diode
(2009-08-18)
Lu
;
Tien-Chang
;
Chen
;
Chyong-Hua
A structure of high power edge emission laser diode that has plural mode extension sublayers with a chirp periodic distribution is provided. The Near Field Pattern (NFP) is an L shape, and the high intensity portion is nicely overlapped with the multi quantum wells. Furthermore, the low intensity portion will extend to the n-type cladding as it can as possible. Accordingly, the optical power density on the mirror surface of the high power edge emission laser diode is lower down and the vertical divergence angle is decreased, so as to prolong its lifetime.
Fine-grained bandwidth control arbiter and the method thereof
(2009-08-18)
Huang
;
Juinn-Dar
;
Lin
;
Bu-Ching
;
Lee
A fine-grained bandwidth control arbiter manages the shared bus usage of the requests of the masters which have real-time and/or bandwidth requirements, moreover, the masters are preset a ticket respectively. The arbiter consists of three components, a real-time handler, a bandwidth regulator, and a lottery manager with tuned weight. The real-time handler grants the most urgent request. The bandwidth regulator handles the bandwidth allocation and blocks the requests of masters that have met the bandwidth requirement. The lottery manager with tuned weight stochastically grants one of the contending masters according to the ticket assignment.
A new water-soluble fluorescent Cu(II) chemosensor based on tetrapeptide histidyl-glycyl-glycyl-glycine (HGGG)
(2009-08-18)
Wu, Shu-Pao
;
Liu, Shi-Rong
;
應用化學系
;
Department of Applied Chemistry
A new water-soluble fluorescent chemosensor Fluor-HGGG was synthesized by linking a tetrapeptide histidyl-glycyl-glycyl-glycine (HGGG) with fluorescein via standard solid-phase 9-fluorenylmethoxycarbonyl (Fmoc) chemistry. Significant fluorescence quenching was observed with Fluor-HGGG in the presence of Cu(2+). Other metal ions including Ag(+) Ca(2+), Cd(2+), Co(2+), Fe(2+), Fe(3+), Hg(2+), Mn(2+), Ni(2+) and Zn(2+) produced only minor changes in fluorescence values for the system. The dissociation constant (K(D)) of Cu(2+) binding in Fluor-HGGG was found to be 37 mu M. The maximum fluorescence quenching caused by Cu(2+) binding in Fluor-HGGG was observed over the pH range 7-7.5. (C) 2009 Elsevier B.V. All rights reserved.
Electronic structure analysis for group III acceptors in Ge under stress considering screening effect and central-cell correction
(2009-08-19)
Wang, T. H.
;
Yen, S. T.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We study theoretically the electronic structures of various group III acceptors in Ge under [001] stress, based on the effective-mass theory with a semi-empirical impurity potential which considers the q-dependent screening and the central-cell correction. An assignment is made for inter-level transition lines which were previously ignored or incorrectly assigned. In addition, our calculation can resolve crowding levels of final states of transition lines which have not been resolved by experimental techniques. The stress effect on the electronic structure can be understood by connecting with the composition of the states. Our results show that the binding energies decrease rapidly with the stress in the low-stress region, and for even-parity states they exhibit remarkable asymmetry in the stress dependence due to the large difference between the heavy-hole and the light-hole compositions. The acceptor states asymptotically approach a pure heavy-hole or light-hole state under high stress. In the limiting case of high stress, extra degeneracy appears. The central-cell correction may cause a significant chemical shift for even-parity states of nonisocoric acceptors. We also complete the assignment of the four line components into which the B line splits under stress. The newly assigned stress-dependent transition energies show excellent agreement with the experimental data for low stress. A justification is made for the applicability of our calculation scheme to the case of high stress.
Long-length fiber Bragg creating sequential UV writing by probing phase mask
(2009-08-20)
Hsu, Kuei-Chu
;
Lai, Yin-Chieh
;
Hsin, Chen-Wei
A new fiber position monitoring method for sequential FBG UV-writing processes with a reference phase mask as the phase reference is proposed. Also, the new method by probing a reference phase mask can overcome the optical alignment difficulties in using reference fiber as well as provide more signal power for achieving better monitoring accuracy. Moreover, the present invention provides a method for sequentially joining a plurality of grating sections into a fiber grating longer than a phase mask.
LICENSE PLATE RECOGNITION SYSTEM USING SPATIAL-TEMPORAL SEARCH-SPACE REDUCTION AND METHOD THEREOF
(2009-08-20)
Wang, Shen-Zheng
;
Lee, Hsi-Jian
The present invention discloses a license plate recognition system by utilizing spatial-temporal search-space reduction and method thereof. The license plate recognition system can selects a pixel with character edge feature from the inputted image and a plurality of candidate regions from the image; and detect if the candidate region of the inputted image has been appeared in a preceding image. Then the recognition system in the present invention separates the candidate region into a plurality of blocks, calculates the repeated block based on a current image and a preceding image, and determines whether the candidate region is repeated according to the repeated block. Thus, by discarding the repeated regions, the license plate recognition system in the present invention can avoid redundant calculation and improve the efficiency and performance for recognition of real plate character in the image.
DYNAMIC CALIBRATION METHOD FOR SINGLE AND MULTIPLE VEDIO CAPTURE DEVICES
(2009-08-20)
Chen, I-Hsien
;
Wang, Sheng-Jyh
The present invention discloses a dynamic calibration method for a single and multiple video capture devices. The present invention can acquire the variations of the pan angle and tilt angle of a single video capture device according to the displacement of the feature points between successive images. For a plurality of video capture devices, the present invention includes the epipolar-plane constraint between a plurality of video capture devices to achieve the goal of dynamical calibration. The calibration method in the present invention does not require specific calibration patterns or complicated correspondence of feature points, and can be applied to surveillance systems with wide-range coverage.
交大e-News第054期
(2009-08-20)
Secretariat
;
國立交通大學秘書室
高產量管線式快速傅立葉轉換處理器
(2009-08-21)
李鎮宜
;
林昱偉
本案提出一種應用於超寬頻(UWB)系統的管線快速傅立葉轉換(FFT)處理器,包括:用以實行基底-2(radix-2)FFT演算的一第一模組、用以實行基底-8FFT演算的一第二模組、用以實行基底-8FFT演算的一第三模組、複數個共軛區塊(conjugate blocks)、一除法區塊以及複數個多工器。所提出之被稱為混合基底多路徑延遲迴授(Mixed-RadixMulti-Path Delay Feedback)的管線FFT結構係藉由使用多資料路徑配置而能夠提供較高的產量率,本案之處理器係使用高基底FFT演算法以降低複雜之乘法演算的數目
Increasing MicroRNA target prediction confidence by the relative R(2) method
(2009-08-21)
Wang, Hsiuying
;
Li, Wen-Hsiung
;
統計學研究所
;
Institute of Statistics
MicroRNAs (miRNAs) are short noncoding RNAs involved in post-transcriptional gene regulation via binding to mRNAs. Studies show that in a multicellular organism microRNAs (miRNAs) downregulate a large number of target mRNAs. However, predicting the target genes of a miRNA is challenging. Microarray expression pro. ling has been proposed as a complementary method to increase the confidence of miRNA target prediction, but it can become computationally costly or even intractable when many miRNAs and their effects across multiple tissues are to be considered. Here, we propose a statistical method, the relative R(2) method, to find high-confidence targets among the set of potential targets predicted by a computational method such as TargetScanS or by microarray analysis, when expression data of both miRNAs and mRNAs are available for multiple tissues. Applying this method to existing data, we obtain many high-confidence targets in mouse. (C) 2009 Elsevier Ltd. All rights reserved.
Increasing MicroRNA target prediction confidence by the relative R-2 method
(2009-08-21)
Wang, Hsiuying
;
Li, Wen-Hsiung
;
統計學研究所
;
Institute of Statistics
MicroRNAs (miRNAs) are short noncoding RNAs involved in post-transcriptional gene regulation via binding to mRNAs. Studies show that in a multicellular organism microRNAs (miRNAs) downregulate a large number of target mRNAs. However, predicting the target genes of a miRNA is challenging. Microarray expression pro. ling has been proposed as a complementary method to increase the confidence of miRNA target prediction, but it can become computationally costly or even intractable when many miRNAs and their effects across multiple tissues are to be considered. Here, we propose a statistical method, the relative R-2 method, to find high-confidence targets among the set of potential targets predicted by a computational method such as TargetScanS or by microarray analysis, when expression data of both miRNAs and mRNAs are available for multiple tissues. Applying this method to existing data, we obtain many high-confidence targets in mouse. (C) 2009 Elsevier Ltd. All rights reserved.
聲源能量分佈可視化系統及其方法
(2009-08-21)
白明憲
;
林家鴻
;
甯攸威
本發明提供一種聲源能量分佈可視化系統及其方法,其係在求得波傳遞矩陣與窗口矩陣後,透過將波傳遞矩陣進行反逆運算,以及將反逆運算結果與窗口矩陣作相乘運算,把相乘運算結果由頻率域轉換成時間域後,建立起聲源能量分佈重建器,而再進一步利用陣列式麥克風接收聲源訊號,且使用多通道擷取裝置將聲源訊號轉換成數位聲源訊號後,讓數位聲源訊號與聲源能量分佈重建器作旋積運算,而得到一可視化之聲源能量分佈。因此,本發明提供一種聲源能量分佈可視化系統及其方法,其可獲得近場及遠場之穩態與非穩態聲源的能量分佈情形,或是任一頻帶內的聲源能量分佈情況。
Highly Emitting Neutral Dinuclear Rhenium Complexes as Phosphorescent Dopants for Electroluminescent Devices
(2009-08-24)
Mauro, Matteo
;
Procopio, Elsa Quartapelle
;
Sun, Yinghui
;
Chien, Chen-Han
;
Donghi, Daniela
A series of neutral, dinuclear, luminescent rhenium(I) complexes suitable for phosphorescent organic light emitting devices (OLEDs) is reported. These compounds, of general formula [Re(2)(mu-Cl)(2)(CO)(6)(mu-1,2-diazine)], contain diazines bearing alkyl groups in one or in both the beta positions. Their electrochemical and photophysical properties are presented, as well as a combined density functional and time-dependent density functional study of their geometry, relative stability and electronic structure. The complexes show intense green/yellow emissions in toluene solution and in the solid state and some of the complexes possess high emission quantum yields (phi = 0.18-0.22 for the derivatives with disubstituted diazines). In butyronitrile glass, at 77 K, due to the charge transfer character of the lowest (emitting) excited state, strong blue shift of the emission is observed, accompanied by a strong increase in the lifetime values. The highest-performing emitting complex, containing cyclopentapyridazine as ligand, is tested in a polymer-based light-emitting device, with poly(9-vinylcarbazole) as matrix, as well as in a device obtained by vacuum sublimation of the complex in the 2,7-bis(diphenylphosphine oxide)-9-(9-phenylcarbazol-3-yl)-9-phenylfluorene (PCF) matrix. This represents the first example of devices obtained with a rhenium complex which can be sublimed and is solution processable. Furthermore, the emission is the bluest ever reported for electrogenerated luminescence for rhenium complexes.
Free alignment defect, low driving voltage of half-V ferroelectric liquid crystal device
(2009-08-24)
Chen, Huang-Ming P.
;
Lin, Chi-Wen
;
光電工程學系
;
顯示科技研究所
;
Department of Photonics
The horizontal chevron alignment defect in half-V mode ferroelectric liquid crystal (FLC) cell can be reduced by asymmetrical alignment hybrid cell. The low free energy level generated from the interaction between spontaneous polarization and opposite polar alignment surfaces was found. As a result, uniformly aligned FLC cell can be achieved without applied external voltage. The R3206 FLC material is applied as model compound. The contrast ratio of R3206-70 is greatly enhanced from 76 to 780 with 1.0 ms response time under 5 V.
Investigation of GaN-based light emitting diodes with nano-hole patterned sapphire substrate (NHPSS) by nano-imprint lithography
(2009-08-25)
Huang, H. W.
;
Lin, C. H.
;
Huang, J. K.
;
Lee, K. Y.
;
Lin, C. F.
In this paper, gallium-nitride (GaN)-based light-emitting diodes (LEDs) with nano-hole patterned sapphire (NHPSS) by nano-imprint lithography are fabricated and investigated. At an injection current of 20mA, the LED with NHPSS increased the light output power of the InGaN/GaN multiple quantum well LEDs by a factor of 1.33, and the wall-plug efficiency is 30% higher at 20mA indicating that the LED with NHPSS had larger light extraction efficiency. In addition, by examining the radiation patterns, the LED with NHPSS shows stronger light extraction with a wider view angle. These results offer promising potential to enhance the light output powers of commercial light-emitting devices using the technique of nano-imprint lithography. (C) 2009 Elsevier B.V. All rights reserved.
MODULATION DEVICE FOR GENERATING OPTICAL SIGNAL WITH QUADRUPLE FREQUENCY AND METHOD THEREOF
(2009-08-27)
CHEN, Jye Hong
;
Lin, Chung-Ting
;
Shih, Po Tsung
;
Peng, Peng-Chun
;
Dai, Sheng Peng
The present invention discloses a modulation device for generating an optical signal with quadruple frequency and the modulation method thereof. The modulation device in the present invention utilizes a commercial integrated modulator, a RF signal generator and a phase shifter to generate an optical signal with quadruple frequency. When the RF signal generator generates a first modulation signal, and the phase shifter shifts the first modulation signal by 90 degrees to generate a second modulation signal, the integrated modulator is biased to transmit the optical signal in maximum value and to modulate the first and second modulation signal so as to generate a output optical signal with quadruple frequency.
System for producing the parameters of a bass-enhanced loudspeaker enclosure
(2009-08-27)
Bai, Ming-Sian R.
;
Zhang, Huan-Sheng
;
Chen, Rong-Liang
A system for producing parameters for a bass-enhanced loudspeaker enclosure; meanwhile, a low-frequency extended frequency, a quality and quantity ratio and radius of a port need to be defined for the system. Also, the resonance frequency of a mechanical system and the quality and quantity of a mechanical system are fixed to obtain the parameters for the frequency ratio, the length of the duct and the cavity volume inside the device, etc. and to manufacture the bass-enhanced loudspeaker enclosure.
On the calculation of rate constants of the small cyclic water cluster by anharmonic RRKM theory
(2009-08-27)
Shao, Ying
;
Yao, Li
;
Lin, Sheng-Hsien
;
應用化學系
;
Department of Applied Chemistry
The rate constants for concerted exchange reaction of the small cyclic water clusters (H(2)O)(n)(3, 4) were calculated with the YL method. The anharmonic effect on the concerted hydrogen exchange reaction was examined. For the trimer water, at temperature 300 K, the anharmonic rate constant is k 4: 70 x 10(-4) s(-1), and for the tetramer water, the value is 0: 55 s(-1). The tunneling effect is very small for this two concerted hydrogen exchange reactions and can be neglected in the two reactions. The results are in reasonable agreement with the value given by Loerting et al. Besides that, the anharmonic effect is not significant for the concerted hydrogen exchange reaction of (H(2)O)(n)(3, 4). (C) 2009 Elsevier B. V. All rights reserved.
MODIFIED TDR METHOD AND APPARATUS FOR SUSPENDED SOLID CONCENTRATION MEASUREMENT
(2009-08-27)
LIN, Chih-Ping
;
Chung, Chih-Chung
This invention utilizes the principle of time domain reflectometry (TDR) to develop an improved apparatus and method for suspended solid concentration (SSC) measurement. The apparatus comprises a TDR sensing waveguide for stably determining an electromagnetic-wave (EM-wave) travel time and a temperature sensor. The TDR sensing waveguide and the temperature sensor are submerged in a suspension to detect the EM-wave travel time and the temperature. A temperature-corrected relationship between EM-wave travel time and SSC is found and used to estimate the SSC. Although TDR has been used for measuring soil moisture content and high SSC, its accuracy is not satisfactory for typical SSC monitoring. The present invention improves the accuracy of TDR in SSC measurement by providing the apparatus and method disclosed herein, which are not affected by an electrical conductivity of the suspension and particle sizes of suspended solids therein, and therefore meet the requirements of general engineering applications and environmental monitoring.
Gray code encoding and decoding method applied to holographic storage devices
(2009-08-27)
Ou-Yang, Mang
;
Chen, Yu-Ta
;
Sun, Ching-Cherng
;
Yang, Tsung-Hsun
A gray code encoding and decoding method applied to holographic storage devices is proposed. The encoding method uses gray levels of a 2D detector to encode a certain amount of original bits of the original data, and then sends them to a spatial light modulator (SLM) for encryption. The decoding method corrects the received gray levels to the original gray levels, and then compares the maximum gray level with the original gray levels to decode the original gray level into binary data. The proposed encoding and decoding method can better make use of storage locations of the 2D detector and get a code rate close to 1.