Browsing by Issue Date, starting with "2013-01-24"

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Thermal Decomposition and Oxidation of CH3OH
(2013-01-24)
Lee, Pei-Fang
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Matsui, Hiroyuki
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Xu, Ding-Wei
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Wang, Niann-Shiah
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應用化學系
Thermal decomposition of CH3OH diluted in Ar has been studied by monitoring H atoms behind reflected shock waves of 100 ppm CH3OH + Ar. The total decomposition rate k(1) for CH3OH + M -> products obtained in this study is expressed as, ln(k(1)/cm(3) molecule(-1) s(-1)) = -(14.81 +/- 1.22) - (38.86 +/- 1.82) X 10(3)/T, over 1359-1644 K. The present result on k(1) is indicated to be substantially smaller than the extrapolation of the most of the previous experimental data but consistent with the published theoretical results [Faraday Discuss. 2002, 119, 191-205 and J. Phys. Chem. A 2007, 111, 3932-3950]. Oxidation of CH3OH has been studied also by monitoring H atoms behind shock waves of (0.35-100) ppm CH3OH + (100-400) ppm O-2 + Ar. For the low concentration CH3OH (below 10 ppm) + O-2 mixtures, the initial concentration of CH3OH is evaluated by comparing evolutions of H atoms in the same concentration of CH3OH with addition of 300 ppm H-2 diluted in Ar. The branching fraction for CH3OH + Ar -> (CH2)-C-1 + H2O + Ar has been quantitatively evaluated from this comparative measurements with using recent experimental result on the yield of H atoms in the reaction of (CH2)-C-1,3 + O-2 [J. Phys. Chem. A 2012, 116, 9245-9254]; i.e., the branching fraction for the above reaction is evaluated as, phi(1a) = 0.20 +/- 0.04 at T = 1880-2050 K, in the 1.3 and 3.5 ppm CH3OH + 100 ppm O-2 samples. An extended reaction mechanism for the pyrolysis and oxidation of CH3OH is constructed based on the results of the present study combined with the oxidation mechanism of natural gas [GRI-Mech 3.0]; evolution of H atoms can be predicted very well with this new reaction scheme over a wide concentration range for the pyrolysis (0.36-100 ppm CH3OH), and oxidation (0.36-100 ppm CH3OH + 100/400 ppm O-2) of methanol.
Design and modeling of InP-based InGaAs/GaAsSb type-II "W" type quantum wells for mid-Infrared laser applications
(2013-01-28)
Pan, C. H.
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Lee, C. P.
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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
We have theoretically studied the InP based InGaAs/GaAsSb /InAlAs type-II "W" quantum wells (QWs) using the eight band k.p theory. The trade-off between the emission wavelength and the magnitude of the transition matrix element was investigated with various structural parameters of the "W" QWs. For the same emission wavelength, the devices with thinner InGaAs/GaAsSb layers and a higher Sb content in GaAsSb could provide higher transition strength. The gain spectra and their peak values at various carrier densities were calculated. We have also found that a more balanced electron and hole masses in the type-II "W" QWs can benefit the material gain. In our designed cases, we have seen that the reduced hole effective mass due to a higher Sb content can partially compensate the gain loss caused by the reduced transition matrix element. Based on the optimized design, a material gain above 10(3) cm(-1) is readily achievable for a single properly designed "W" quantum well. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4789634]
Frequency-domain formulation of photonic crystals using sources and gain
(2013-01-28)
Chiang, Po-Jui
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Chang, Shu-Wei
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光電工程學系
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Department of Photonics
We present a formulation to analyze photonic periodic structures from viewpoints of sources and gain. The approach is based on a generalized eigenvalue problem and mode expansions of sources which sustain optical fields with phase boundary conditions. Using this scheme, we calculate power spectra, dispersion relations, and quality factors of Bloch modes in one-dimensional periodic structures consisting of dielectrics or metals. We also compare the results calculated from this scheme with those from the complex-frequency method. The outcomes of these two approaches generally agree well and only deviate slightly in the regime of low quality factors. (C) 2013 Optical Society of America
Vertical-cavity and randomly scattered lasing from different thicknesses of epitaxial ZnO films grown on Y2O3-buffered Si (111)
(2013-01-28)
Kuo, C. C.
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Liu, W. -R.
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Lin, B. H.
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Hsieh, W. F.
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Hsu, C. -H.
Two different types of lasing modes, vertical Fabry-Perot cavity and random lasing, were observed in ZnO epi-films of different thicknesses grown on Si (111) substrates. Under optical excitation at room temperature by a frequency tripled Nd:YVO4 laser with wavelength of 355 nm, the lasing thresholds are low due to high crystalline quality of the ZnO epitaxial films, which act as microresonators. For the thick ZnO layer (1,200 nm), its lasing action is originated from the random scattering due to the high density of crack networks developed in the thick ZnO film. However, the low crack density of the thin film (555 nm) fails to provide feedback loops essential for random scattering. Nevertheless, even the lower threshold lasing is achieved by the Fabry-Perot cavity formed by two interfaces of the thin ZnO film. The associated lasing modes of the thin ZnO film can be characterized as the transverse Gaussian modes attributed to the smooth curved surfaces. (C) 2013 Optical Society of America
Influence of molybdenum doping on the switching characteristic in silicon oxide-based resistive switching memory
(2013-01-28)
Chen, Yu-Ting
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Chang, Ting-Chang
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Huang, Jheng-Jie
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Tseng, Hsueh-Chih
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Yang, Po-Chun
This report compares Mo-doped and undoped SiO2 thin films of a similar thickness as well as MoOx. The Mo-doped SiO2 film exhibited switching behavior after the forming process, unlike the undoped SiO2 film. Through material analyses, a self-assembled layer is observed in the Mo-doped SiO2 film. Due to the formation of this layer, the thickness required to be broken down is effectively reduced. Subsequently, the occurrence of the switching behavior in the thinner SiO2 film further confirmed the supposition. A comparison of the two switching behaviors shows that SiO2 dominates the switching characteristic of the Mo-doped SiO2. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4790277]
Compact high-pulse-energy passively Q-switched Nd:YLF laser with an ultra-low-magnification unstable resonator: application for efficient optical parametric oscillator
(2013-01-28)
Cho, C. Y.
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Huang, Y. P.
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Huang, Y. J.
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Chen, Y. C.
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Su, K. W.
We exploit an ultra-low-magnification unstable resonator to develop a high-pulse-energy side-pumped passively Q-switched Nd:YLF/Cr4+:YAG laser with improving beam quality. A wedged laser crystal is employed in the cavity to control the emissions at 1047 nm and 1053 nm independently through the cavity alignment. The pulse energies at 1047 nm and 1053 nm are found to be 19 mJ and 23 mJ, respectively. The peak powers for both wavelengths are higher than 2 MW. Furthermore, the developed Nd:YLF lasers are employed to pump a monolithic optical parametric oscillator for confirming the applicability in nonlinear wavelength conversions. (C) 2013 Optical Society of America
Control apparatus and method
(2013-01-29)
Lee Chia Hoang
;
Lin Jian Liang
The invention discloses a control apparatus capable of providing a user with a control over an object displayed on a display apparatus by a pointing device. The control apparatus includes an image capturing module, a separating module, a positioning module, a constructing module, and a processing module. The image capturing module is used to record an image sequence included N images. The separating module is applied to capture the pointing device image related to the pointing device from each image. The positioning module is used for calculating a specific point of the pointing device image of each image to generate a first set of specific point information. The constructing module is applied to generate a trajectory in accordance with a pre-defined criterion and the first set of specific point information. Additionally, the processing module is used to analyze the trajectory and generate a control signal to control the object.
Memory-based FFT/IFFT processor and design method for general sized memory-based FFT processor
(2013-01-29)
Lee Chen-Yi
;
Hsiao Chen-Fong
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Chen Yuan
For a large size FFT computation, this invention decomposes it into several smaller sizes FFT by decomposition equation and then transform the original index from one dimension into multi-dimension vector. By controlling the index vector, this invention could distribute the input data into different memory banks such that both the in-place policy for computation and the multi-bank memory for high-radix structure could be supported simultaneously without memory conflict. Besides, in order to keep memory conflict-free when the in-place policy is also adopted for I/O data, this invention reverses the decompose order of FFT to satisfy the vector reverse behavior. This invention can minimize the area and reduce the necessary clock rate effectively for general sized memory-based FFT processor design.
Thermodynamics of Protein Folding using a Modified Wako-Saito-Munoz-Eaton Model
(2013-01-29)
Tsai, Min-Yeh
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Yuan, Jian-Min
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Teranishi, Yoshiaki
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Lin, Sheng Hsien
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交大名義發表
Phosphors and light-emitting devices using the same
(2013-01-29)
Chen Teng-Ming
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Kuo Te-Wen
The present invention relates to novel phosphors, which are represented by a formula of (A1-xMx)8D12O24S2, wherein x, A, M and D are defined the same as the specification. In addition, the present invention further provides a light-emitting device using the above novel phosphors.
Live Cell Imaging of GFP-Rab Gtpases allows for Intracellular, Spatiotemporal Tracking of Surface Functionalized Lipid-DNA Complexes
(2013-01-29)
Majzoub, Ramsey N.
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Chan, Chia-Ling
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Ewert, Kai K.
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Liang, Keng S.
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Safinya, Cyrus R.
Noncovalent interaction and its influence on excited-state behavior: A theoretical study on the mixed coaggregates of dicyanonaphthalene and pyrazoline
(2013-01-29)
Dai, Yulan
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Guo, Meiyuan
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Peng, Jingdong
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Shen, Wei
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Li, Ming
In the present letter we investigate the noncovalent interactions in the mixed coaggregates of 1,3,5-triphenyl-2-pyrazoline (TPP) and 1,4-dicyanonaphthalene (DCN) and their influence on the excited-state properties of the TPP-DCN. The theoretical results show that the pi-pi stacking interactions play an important role in the noncovalent interactions of the TPP-DCN coaggregates. The effect of the pi-pi interactions on the excited-state properties of the TPP-DCN is also fully investigated, and the results indicate that the TPP and DCN do not form an intermolecular charge-transfer complex in the ground state, whereas they form an exciplex in the excited state. (C) 2012 Elsevier B. V. All rights reserved.
Variability of volume strain in bounded heterogeneous media
(2013-01-30)
Chang, Ching-Min
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Yeh, Hund-Der
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環境工程研究所
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Institute of Environmental Engineering
The deformation of the solid matrix affects the fluid pore pressure and flow by altering the pore volume. Such interaction in turn affects the storage of groundwater in the void space. Obviously, this subject is of interest in groundwater hydrology. This paper describes an investigation of the effect of aquifer heterogeneity on the variability of the fluid pressure head and solid's volume strain, where the assumption of a constant vertical total stress leads to a relatively simple relationship between changes in solid's volume strain and fluid pressure head. To solve the problem analytically, focus is placed on the one-dimensional models. It is found from our closed-form solutions that the variance and correlation length of the log hydraulic conductivity are important in increasing the variability of pressure head and solid's volume strain. It is hoped that our findings will provide a basic framework for understanding and quantifying field-scale volume strain processes and be useful in stimulating further research in this area. Copyright (C) 2011 John Wiley & Sons, Ltd.
PHYSIOLOGICAL SIGNAL COLLECTION UNIT AND DETECTOR THEREOF
(2013-01-31)
Chiou Jin-Chern
;
Huang Yu-Chieh
A physiological signal collection unit is for use with a physiological signal measuring apparatus to measure physiological signals from an anatomical part of a test subject, in which the anatomical part is covered with hair. The physiological signal collection unit includes a detector and a wearable member. The detector includes a circuit substrate defining a substrate-through-hole to permit hair strands to extend through, an electrical connector, and at least one signal collecting component. The wearable member is to be worn on the anatomical part of the test subject, and is formed with a through-hole having a size smaller than size of the circuit substrate. The through-hole permits the hair strands extending through the circuit substrate to extend through the wearable member.
Theoretical Study on Structure and Sum-Frequency Generation (SFG) Spectroscopy of Styrene-Graphene Adsorption System
(2013-01-31)
Lin, Chih-Kai
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Shih, Chun-Chi
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Niu, Yingli
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Tsai, Min-Yeh
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Shiu, Ying-Jen
In this theoretical study, we aimed to simulate the sum-frequency generation (SFG) spectroscopy of a thin polystyrene layer physically adsorbed on the graphene sheet and to figure out the orientation distribution of the phenyl units. To simplify the problem, we started the investigation by constructing molecular models with styrene and ethylbenzene monomers and styrene oligomers up to four units adsorbed on a finite-sized graphene hexagon. Geometric optimization results showed that the phenyl rings of the adsorbate always orientate close to the surface normal with a small tilt angle. The adsorption is weak but not negligible. SFG spectra have been simulated based on these calculated structures, vibrational frequencies, and dipole and polarizability derivatives to compare with experimental reports of polystyrene adsorbed on other surfaces.
METHOD AND DEVICE FOR DECODING A SCALABLE VIDEO SIGNAL UTILIZING AN INTER-LAYER PREDICTION
(2013-01-31)
CHANG YUNG
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HUANG PO-TSANG
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HWANG WEI
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CHEN YU-CHEN
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LI GWO-LONG
A method and device for decoding a scalable video signal utilizing an inter-layer prediction are provided herein. An inter-layer pre-fetch scheme (IPS) is presented to improve the performance for scalable video coding (SVC) decoder. With proposed invention, the required information for inter-layer prediction in SVC technique will be pre-fetched ahead when reconstructing the enhancement layer so that the cache miss rate can be reduced significantly. Accordingly, the execution time and memory energy consumptions can be improved.
SYSTEM AND METHOD FOR ALLOCATING CACHE MEMORY
(2013-01-31)
CHANG Yung
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Huang Po-Tsang
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Hwang Wei
Different processor elements in multi-task/multi-core system on chip may have different memory requirements at runtime. The method for adaptively allocating cache memory re-allocates the cache resource by updating the bank assignment table. According to the associativity-based partitioning scheme, centralized memory is separated into several groups of SRAM banks which are numbered differently. These groups are assigned to different processor elements to be L2 caches. The bank assignment information is recoded in bank assignment table, and is updated by system profiling engine. By changing the information in bank assignment table, the cache resource re-allocation for processor elements is achieved.
Recent trend in graphene for optoelectronics
(2013-02-01)
Chen, Yu-Bin
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Liu, John S.
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Lin, Pang
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材料科學與工程學系
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Department of Materials Science and Engineering
This study analyzes the scientific knowledge diffusion paths of graphene for optoelectronics (GFO), where graphene offers wide applications due to its thinness, high conductivity, excellent transparency, chemical stability, robustness, and flexibility. Our investigation is based on the main path analysis which establishes the citation links among the literature data in order to trace the significant sequence of knowledge development in this emerging field. We identify the main development paths of GFO up to the year 2012, along which a series of influential papers in this field are identified. The main path graph shows that knowledge diffusion occurs in key subareas, including reduced graphene oxide, chemical vapor deposition, and exfoliation techniques, which are developed for the preparation and applications of GFO. The applications cover solar cells, laser devices, sensing devices, and LCD. In addition, the main theme of GFO research evolves in sequence from small-graphene-sample preparation, to large-scale film growth, and onto prototype device fabrication. This evolution reflects a strong industrial demand for a new transparent-conductive film technology.
Freeway drivers' willingness to pay for an on board unit under an electronic toll collection system
(2013-02-01)
Jou, Rong-Chang
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Chiou, Yu-Chiun
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Kuo, Chung-Wei
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Tan, Hao-I
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運輸與物流管理系註：原交通所+運管所
Electronic toll collection (ETC) systems have been put into practice in one or two channels at toll plazas on Taiwan's freeways since 2006. The utilisation of the ETC system has been flat due to the extra cost of installing the on board unit (OBU) that is used in the system. To increase the utilisation rate of the ETC system, it is crucial to understand the real price that drivers are willing to pay. Therefore, this study investigates freeway drivers' willingness to pay a value for an OBU. A stated preference experiment is designed to obtain the willingness to pay at three different levels of use. To avoid the estimation bias due to a large percentage with a zero willingness to pay, a spike model is used. Different markets are segmented to examine their willingness to pay for an OBU. The estimation results show that the willingness to pay for an OBU is NT$727/unit(1) for short distance drivers, NT$830 for medium distance drivers, and NT$1308/unit for long distance drivers. (C) 2012 Elsevier Ltd. All rights reserved.
Design of Bidirectional and Low Power Consumption Gate Driver in Amorphous Silicon Technology for TFT-LCD Application
(2013-02-01)
Zheng, Guang-Ting
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Liu, Po-Tsun
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Wu, Meng-Chyi
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Chu, Li-Wei
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Yang, Meng-Chuan
A new gate driver has been designed and fabricated by amorphous silicon (a-Si) technology. With utilizing four clock signals in the design of gate driver on array (GOA), the pull-up transistor has ability for both output charging and discharging, and layout size of the proposed gate driver can be narrowed for bezel panel application. Moreover, lower duty cycle of clock signals can decrease static power loss to further reduce the overall power consumption of the proposed gate driver. The scan direction of the proposed gate driver can be adjusted by switching two direct control signals to present the reversal display of image. The proposed gate driver has been successfully demonstrated in a 4.5-inch WVGA (480 x RGB x 800) TFT-LCD panel and passed reliability tests of the supporting foundry.