Browsing by Issue Date, starting with "2018-11-21"

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Holographic entanglement entropy in boundary conformal field theory
(2018-11-21)
Chang, En-Jui
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Chou, Chia-Jui
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Yang, Yi
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電子物理學系
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Department of Electrophysics
We study the holographic entanglement entropy in a (d + 1)-dimensional boundary quantum field theory at both the zero and finite temperature. The phase diagrams for the holographic entanglement entropy at various temperatures are obtained by solving the entangled surfaces in the different homology. We also verify the Araki-Lieb inequality and illustrate the entanglement plateau.
STEREOSCOPIC IMAGING METHOD AND DEVICE
(2018-11-22)
Tian-Sheuan CHANG
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Yi-Chun CHEN
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Jen-Hui CHUANG
A stereoscopic imaging method includes: acquiring a convergence disparity value, which corresponds to a screen position at which a viewer is looking, from an original disparity map corresponding to first and second images that correspond to different viewing angles; generating a disparity transformation model based on the convergence disparity value and viewer-related information; transforming the original disparity map into a transformed disparity map based on the disparity transformation model; and synthesizing the first and second images into a stereoscopic image based on the transformed disparity map.
Integral Method Analysis of Electroabsorption Spectra and Electrophotoluminescence Study of (C4H9NH3)(2)Pbl(4) Organic-Inorganic Quantum Well
(2018-11-22)
Kattoor, Vidya
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Awasthi, Kamlesh
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Jokar, Efat
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Diau, Eric Wei-Guang
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Ohta, Nobuhiro
Electric-field-induced changes in absorption and photoluminescence (PL) spectra and in PL decay profile have been measured for two-dimensional hybrid organic inorganic halide perovskite semiconductor, ((C4H9NH3)(2)Pbl(4)) (N1). Electroabsorption (E-A) spectra observed at room temperature and at a low temperature of 45 K were analyzed by assuming the Stark shift, and the magnitudes of the change in electric dipole moment and polarizability following photoexcitation were determined. The strong signal observed in the E-A spectra at 45 K was interpreted in terms of the weak absorption band which shows extremely large Stark shift resulting from the large change in polarizability following photoexcitation. Electrophotoluminescence spectra of this compound, that is, field-induced change in PL spectra, show that PL of N1 is quenched by the application of electric field. Field effects on PL decay profiles show that the quenching results both from the field-induced decrease of the population of the emitting state following photoexcitation and from the field-induced lifetime shortening caused by the enhancement of the nonradiative decay rate at the emitting state. At a low temperature of 45 K, two exciton emissions, each of which originates from different phase, appear, and both emissions are quenched by the applied electric field with different efficiencies from each other. It is also found that trap emissions observed at low temperature in the wavelength region longer than the sharp exciton bands show more efficient field-induced quenching than that of the exciton emissions, suggesting that energy transfer from the photoexcited state to trapped states is decelerated by the applied electric field.
A Water-Soluble NaCMC/NaPAA Binder for Exceptional Improvement of Sodium-Ion Batteries with an SnO2-Ordered Mesoporous Carbon Anode
(2018-11-23)
Patra, Jagabandhu
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Rath, Purna Chandra
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Li, Chi
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Kao, Hsien-Ming
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Wang, Fu-Ming
SnO2@CMK-8 composite, a highly promising anode for Na-ion batteries (NIBs), was incorporated with polyvinylidene difluoride (PVDF), sodium carboxymethylcellulose (NaCMC), sodium polyacrylate (NaPAA), and NaCMC/NaPAA mixed binders to optimize the electrode sodiation/desodiation properties. Synergistic effects between NaCMC and NaPAA led to the formation of an effective protective film on the electrode. This coating layer not only increased the charge-discharge Coulombic efficiency, suppressing the accumulation of solid-electrolyte interphases, but also kept the SnO2 nanoparticles in the CMK-8 matrix, preventing the agglomeration and removal of oxide upon cycling. The adhesion strength and stability towards the electrolyte of the binders were evaluated. In addition, the charge-transfer resistance and apparent Na+ diffusion of the SnO2@CMK-8 electrodes with various binders were examined and post-mortem analyses were conducted. With NaCMC/NaPAA binder, exceptional electrode capacities of 850 and 425 mAh g(-1) were obtained at charge-discharge rates of 20 and 2000 mA g(-1), respectively. After 300 cycles, 90 % capacity retention was achieved. The thermal reactivity of the sodiated electrodes was studied by using differential scanning calorimetry. The binder effects on NIB safety, in terms of thermal runaway, are discussed.
草地x藝術　交大西區藝術節
(2018-11-25)
彭姿敏
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郭玟妤
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Department of Communication and Technology
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傳播與科技學系
2018交大西區藝術節配合校慶60週年，聯合清交草地音樂季，舉辦一系列藝文活動，帶領大家體會校園藝文生態之美。
台灣補習教育之現象　
(2018-11-25)
林函諭
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Department of Communication and Technology
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傳播與科技學系
關於補習這件事，已聚訟紛紜多年。補習教育在台灣究竟該何以得解？
胡子睿　用手語編織的夢想
(2018-11-25)
廖庭歡
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Department of Communication and Technology
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傳播與科技學系
胡子睿拍攝了兩部手語舞蹈影片，分別是《成全》、《半島鐵盒》，在網路上造成廣大迴響，手語對他來說，是生命無法減去的熱愛。
你有拖延症嗎？
(2018-11-25)
李欣秝
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Department of Communication and Technology
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傳播與科技學系
每個人的人生幾乎都有拖延的情形發生，不管你是學生、上班族或是大老闆，大家都可能因為某些原因而不斷地在拖延，以下將探討拖延發生的原因和可能的解決方法。
設計師之路從襪子開始　楊慧淳
(2018-11-25)
汪彥彤
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Department of Communication and Technology
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傳播與科技學系
毅然決然放棄薪水穩定的公職，楊慧淳用不起眼的襪子設計出更精彩的人生。
織繡、布匹與夢　「布博」
(2018-11-25)
李庭安
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Department of Communication and Technology
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傳播與科技學系
2018年11月10號至11號，布博（nunohaku）於華山文化創意產業園區開展，在色彩、織繡與布之間，裁紉出創作者的夢。
觀光更自由？網約導遊到此一遊
(2018-11-25)
呂奕廷
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Department of Communication and Technology
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傳播與科技學系
近年來中國興起的網約導遊，顛覆以往由旅行社指派的模式，讓導遊得以自由執業。究竟在這一波新的旅遊模式下，台灣應該如何看待並走出導遊觀光的未來？
總編輯的話
(2018-11-25)
陳儀軒
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Department of Communication and Technology
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傳播與科技學系
本期為喀報的第303期，共計九篇文章，以人物故事為主。本期頭題為梁書瑜的〈吳淑美　融合教育的幕後推手〉，人物介紹有深度，且文字充滿溫度，字裡行間中能見人物的特質與經歷，文情並茂，讀來十分親切。
TAOS based Cu/TiW/IGZO/Ga2O3/Pt bilayer CBRAM for low-power display technology
(2018-11-25)
Gan, Kai-Jhih
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Liu, Po-Tsun
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Chiu, Yu-Chuan
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Ruan, Dun-Bao
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Chien, Ta-Chun
We demonstrate the characteristics of a conductive-bridging random access memory (CBRAM) with Cu/TiW/InGaZnO/Ga2O3/Pt stack structure. The addition of a thin metal-oxide layer (4.5 nm-thick Ga2O3) in the bottom of the CBRAM device significantly increases the off-state resistance (Rom') and the memory window. The IGZO bi-layer CBRAM shows the excellent memory performances, such as low operation current (down to 50 A), high on/off resistance ratio (> 10(3)), high switching endurance (up to 10(3) cycles) and the capability of multi-level tuning. Meanwhile, high thermal stability was also achieved. Three decades of resistance window is constantly maintained beyond 10(4)s at 85 degrees C. The resistive switching stability and electrical uniformity of bi-layer IGZO/Ga2O3 CBRAM device are obviously enhanced as compared with the one only with a single layer of IGZO film. These results have given a great potential for the transparent amorphous oxide semiconductor (TAOS)-based material utilizing in CBRAM stacks and integrating into the display circuits for future memory-in-pixel applications.
吳淑美　融合教育的幕後推手
(2018-11-25)
梁書瑜
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Department of Communication and Technology
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傳播與科技學系
融合教育是將普通生和特殊生放在一起上課的教學模式。在這，普通孩子是大天使，特殊孩子是小天使，他們坐在同一間教室裡，不分你我，一起生活。
掙脫深淵　綻放新生——陳慧珠
(2018-11-25)
王允妍
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Department of Communication and Technology
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傳播與科技學系
「人生就像寫故事一樣，上半部寫得非常非常地爛，但我下半部人生是越寫越精彩！」
eDRAM: Effective early disease risk assessment with matrix factorization on a large-scale medical database: A case study on rheumatoid arthritis
(2018-11-26)
Chin, Chu-Yu
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Hsieh, Sun-Yuan
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Tseng, Vincent S.
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資訊科學與工程研究所
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Institute of Computer Science and Engineering
Recently, a number of analytical approaches for probing medical databases have been developed to assist in disease risk assessment and to determine the association of a clinical condition with others, so that better and intelligent healthcare can be provided. The early assessment of disease risk is an emerging topic in medical informatics. If diseases are detected at an early stage, prognosis can be improved and medical resources can be used more efficiently. For example, if rheumatoid arthritis (RA) is detected at an early stage, appropriate medications can be used to prevent bone deterioration. In early disease risk assessment, finding important risk factors from large-scale medical databases and performing individual disease risk assessment have been challenging tasks. A number of recent studies have considered risk factor analysis approaches, such as association rule mining, sequential rule mining, regression, and expert advice. In this study, to improve disease risk assessment, machine learning and matrix factorization techniques were integrated to discover important and implicit risk factors. A novel framework is proposed that can effectively assess early disease risks, and RA is used as a case study. This framework comprises three main stages: data preprocessing, risk factor optimization, and early disease risk assessment. This is the first study integrating matrix factorization and machine learning for disease risk assessment that is applied to a nation-wide and longitudinal medical diagnostic database. In the experimental evaluations, a cohort established from a large-scale medical database was used that included 1007 RA-diagnosed patients and 921,192 control patients examined over a nine-year follow-up period (2000-2008). The evaluation results demonstrate that the proposed approach is more efficient and stable for disease risk assessment than state-of-the-art methods.
Generating high-power asymmetrical Laguerre-Gaussian modes and exploring topological charges distribution
(2018-11-26)
Hsieh, Y. H.
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Lai, Y. H.
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Hsieh, M. X.
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Huang, K. F.
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Chen, Y. F.
We employ an off-axis pumped Nd:YVO4 laser and control the reflectance of output coupler to directly generate asymmetrical Hermite-Gaussian (HG) modes with various transverse orders. By using an astigmatic mode converter, the generated asymmetrical HG modes are straightforwardly transformed into asymmetrical Laguerre-Gaussian (LG) modes with a crescent-like shape. The average output power of all the crescent-shaped LG modes can exceed 1W at the pump power of 4W. Furthermore, experimental results are theoretically verified by resonant modes derived from the inhomogeneous Helmholtz equation with the localized source distribution. Theoretical resonant modes are also used to explore the dependence of the phase structures of LG modes on the system loss. As the loss increases, it is found that the singularities at the origin will be rearranged and new singularities are formed in the outside region with average orbital angular momentum remaining unchanged. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Solid-state emitter embedded in a microcavity under intense excitation: A variational master-equation approach
(2018-11-26)
Gomez-Sanchez, Oscar J.
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Ramirez, Hanz Y.
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電子物理學系
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Department of Electrophysics
In this work, dissipative effects from a phonon bath on the resonance fluorescence of a solid-state two-level system embedded in a high-quality semiconductor microcavity and driven by an intense laser are investigated. Within the density operator formalism, we derive a variational master equation valid for broader ranges of temperatures, pumping rates, and radiation-matter couplings than previous studies. From the obtained master equation, fluorescence spectra for various thermal and exciting conditions are numerically calculated and compared to those computed from weak coupling and polaronic master equations, respectively. Our results evidence the breakdown of those rougher approaches under increased temperature and strong pumping.
From Block Copolymer Nanotubes to Nanospheres: Nonsolvent-Induced Morphology Transformation Using Porous Templates
(2018-11-27)
Chang, Chun-Wei
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Tu, Yi-Hsuan
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Luo, Ke-Hsuan
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Chen, Jiun-Tai
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交大名義發表
Block copolymer nanostructures have attracted great attention because of the wide range of applications such as sensors and drug delivery. The fabrication of block copolymer nanostructures with controlled morphologies and sizes, however, is still challenging. Here, we study the fabrication of nanotubes and nanospheres of polystyrene-block-polybutadiene (PS-b-PBD) using anodic aluminum oxide (AAO) templates. When PS-b-PBD solutions in N-methyl-2-pyrrolidone are introduced into the nanopores of the AAO templates applying the traditional solution wetting method, PS-b-PBD nanotubes can be obtained. When PS-b-PBD solutions in the nanopores are in contact with a nonsolvent, acetic acid, PS-b-PBD nanospheres are formed. Two possible mechanisms are proposed to discuss the formation of the nonsolvent-driven morphology transformation, including the Rayleigh-instability-type transformation mechanism and the nucleation and growth mechanism. The effect of the polymer concentrations on the internal morphologies of the PS-b-PBD nanostructures is discussed; at higher concentrations, PS-b-PBD nanocapsules can also be prepared. Furthermore, core-shell PS-b-PBD/polymethylmethacrylate nanospheres can be fabricated using this strategy with polymer blend solutions. This work not only demonstrates a simple strategy to control the morphologies of block copolymer nanostructures but also deepens the understanding of the interactions between polymer solutions and solvents.
Infrared spectra of the 1,1-dimethylallyl and 1,2-dimethylallyl radicals isolated in solid para-hydrogen
(2018-11-28)
Amicangelo, Jay C.
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Lee, Yuan-Pern
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交大名義發表
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應用化學系
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應用化學系分子科學碩博班
The reaction of hydrogen atoms (H) with isoprene (C5H8) in solid para-hydrogen (p-H2) matrices at 3.2 K has been studied using infrared (IR) spectroscopy. Mixtures of C5H8 and Cl-2 were co-deposited in p-H2 at 3.2 K, followed by irradiation with ultraviolet light at 365 nm to produce Cl atoms from the Cl-2, and subsequent irradiation with IR light to produce H atoms from the reaction of the Cl atoms with p-H-2. The H atoms then react with the C5H8 to form H atom addition radicals (C5H9 center dot). Upon 365-nm/IR photolysis, a multitude of new lines appeared in the IR spectrum and, based on the secondary photolysis behavior, it was determined that the majority of the new lines belong to two distinct chemical species, denoted as setX(an intense line at 776.0 cm 1 and 12 other weaker lines) and set Y (an intense line at 766.7 cm(-1) and 12 other weaker lines). Quantum-chemical calculations were performed at the B3PW91/6-311++ G(2d, 2p) level to determine the relative energetics and predict the IR spectra for the four possible isomers of C5H9 center dot that can be produced from the addition of the H atom to the four distinct carbon atoms in C5H8. The newly observed lines of set X and Y are assigned to the 1,2-dimethylallyl (addition to carbon 4) and the 1,1-dimethylallyl (addition to carbon 1) radicals according to comparison with the predicted IR spectra of the possible products. The 1,2-dimethylallyl radical and the 1,1-dimethylallyl radical were predicted to be the most stable isomers, with the latter similar to 8 kJ mol(-1) lower in energy than the former and to have significantly lower barriers than the addition pathways for the two central carbons. The ratio of the 1,1-dimethylallyl to the 1,2-dimethylallyl radicals is estimated to be (1.0 +/- 0.5): 1.0, indicating that the two radicals are produced in similar amounts, which is consistent with the theoretical predictions that the barrier heights are very similar for the H atom addition to the two terminal carbon atoms. Published by AIP Publishing.