Browsing by Issue Date, starting with "2019-03"

Now showing 1 - 20 of 8128

Bromine-Radical-Mediated Site-Selective Allylation of C(sp(3))-H Bonds
(2019-03-01)
Ueda, Mitsuhiro
;
Maeda, Ayami
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Hamaoka, Kanako
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Sasano, Mika
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Fukuyama, Takahide
The C(sp(3))-H allylation of alkanes is investigated by using allyl bromides under radical reaction conditions. In many cases, methine C-H allylation preceded methylene and methyl C-H allylation with complete or a high degree of site selectivity. The C-H allylation of allylic compounds, such as allylbenzene, gives 1,5-dienes with the S(H)2' reactions of the allyl radicals occurring at the less hindered carbon.
Hexanoyl chitosan/ENR25 blend polymer electrolyte system for electrical double layer capacitor
(2019-03-01)
Winie, Tan
;
Jamal, Asheila
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Saaid, Farish Irfal
;
Tseng, Tseung-Yuen
;
電子工程學系及電子研究所
Single salt polymer electrolytes based on hexanoyl chitosan-ENR25 were prepared by employing LiN (CF3SO2)(2) or LiCF3SO3 as the doping salt. Elastic property of hexanoyl chitosan was enhanced with the incorporation of ENR25. DSC studies revealed immiscibility of hexanoyl chitosan and ENR25, and dissolution of salt was favored in ENR25 phase. Conductivity enhancement was observed in the blends as compared with the neat hexanoyl chitosan. The maximum conductivities achieved for LiCF3SO3- and LiN (CF3SO2)(2)-comprising electrolyte systems were 1.6 x 10(-8) and 5.0 x 10(-7) S cm(-1), respectively. Deconvolution of spectra bands in the v(as) (SO2-) mode of LiN (CF3SO2)(2) and v(s) (SO3-) mode of LiCF3SO3 has been carried out to estimate the relative percentage of free ions and associated ions. The findings were in good agreement with conductivity results. Electrical double layer capacitor (EDLC) was fabricated with hexanoyl chitosan/ENR25 (90:10)-LiN (CF3SO2)(2)-EmImTFSI electrolyte and activated carbon-based electrodes. The conductivity and electrochemical stability window of hexanoyl chitosan/ENR25-LiN (CF3SO2)(2)-EmImTFSI were similar to 10(-6) S cm(-1) and 2.7 V, respectively. The performance of the EDLC was analyzed by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). From GCD, the specific capacitance of EDLC was 58.0 F g(-1) at 0.6 mA cm(-2). The specific capacitance was found to decrease with increasing current density.
A trading decision support model to maximize the sustainability of a self-financed guaranteed farmgate price program
(2019-03-01)
Chen, Wen-Chih
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Wu, Cheng-Hung
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工業工程與管理學系
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Department of Industrial Engineering and Management
We study a non-government organization (NGO) program that supports the household livelihood of small farmers by committing to purchase a fixed quantity at a guaranteed farmgate price of a storable agri-product under price fluctuation. Since the World Trade Organization (WTO) disciplines its members to limit and reduce domestic support for the agriculture, storing and trading (selling) the product on the spot market at a favorable price generates revenue to cover the cost of the program. The objective of this study is to develop a stochastic dynamic trading decision model that maximizes the sustainability of the NGO's supporting program, measured as the survival probability, i.e. the probability that the program can continue operating after a predetermined period of time. The results of a numerical study, based on the tilapia aquaculture in Taiwan, show that our model yields higher survival probability (after 4 years) than the profit-maximization policy by close to 10% in average. Moreover, the trading decision optimization is particularly suitable for market environments with high price fluctuation, i.e. the most challenging circumstances for small farmers.
Sheaf lines of Yang-Mills instanton sheaves
(2019-03-01)
Lai, Sheng-Hong
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Lee, Jen-Chi
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Tsai, I-Hsun
;
電子物理學系
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Department of Electrophysics
We calculate a sheaf line in CP3 which is the real line supporting sheaf points on CP3 of SL(2, C) Yang-Mills (YM) instanton (or SU(2) complex YM instanton) sheaves for some given ADHM data we obtained previously. We found that this sheaf line is indeed a special jumping line over S-4 spacetime. In addition, we calculate the singularity structure of the connection A and the field strength F at the corresponding singular point on S-4 of this sheaf line. We found that the order of singularity at the singular point on S-4 associated with the sheaf line in CP3 is higher than those of other singular points associated with normal jumping lines. We conjecture that this is a general feature for sheaf lines among jumping lines.
Design Automation for Dilution of a Fluid Using Programmable Microfluidic Device-Based Biochips
(2019-03-01)
Gupta, Ankur
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Huang, Juinn-Dar
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Yamashita, Shigeru
;
Roy, Sudip
;
電子工程學系及電子研究所
Microfluidic lab-on-a-chip has emerged as a new technology for implementing biochemical protocols on small-sized portable devices targeting low-cost medical diagnostics. Among various efforts of fabrication of such chips, a relatively new technology is a programmable microfluidic device (PMD) for implementation of flow-based lab-on-a-chip. A PMD chip is suitable for automation due to its symmetric nature. In order to implement a bioprotocol on such a reconfigurable device, it is crucial to automate a sample preparation on-chip as well. In this article, we propose a dilution PMD algorithm (namely DPMD) and its architectural mapping scheme (namely generalized architectural mapping algorithm (GAMA)) for addressing fluidic cells of such a device to perform dilution of a reagent fluid on-chip. We used an optimization function that first minimizes the number of mixing steps and then reduces the waste generation and further reagent requirement. Simulation results show that the proposed DPMD scheme is comparative to the existing state-of-the-art dilution algorithm. The proposed design automation using the architectural mapping scheme reduces the required chip area and, hence, minimizes the valve switching that, in turn, increases the life span of the PMD-chip.
【學術交流】華盛頓大學黃正能教授演講
(國立交通大學資訊學院, 2019-03)
黃粵丞/資科工博士生
黃正能教授，於1981 和1983 年在台灣大學取得電子工程學士與碩士學位，並於1988 年在University of Southern California 取得博士學位。在1989 年在華盛頓大學任職，研究的領域為多媒體訊號處理、多媒體網路、影像處理、電腦視覺及圖形識別，已在國際期刊、國際會議論文集、書籍和書籍章節發表超過300 篇研究論文。黃正能教授於10 月21 日應邀蒞臨資訊學院演講，講題為：Coordinated Visual 3D Physical World Exploration for Smart City，本次演講探討3D 視覺技術如何應用在未來的智慧城市發展，旁及一些有趣的研究方向，並討論相關的理論基礎及研究成果。
Control of plasmon dephasing time using stacked nanogap gold structures for strong near-field enhancement
(2019-03-01)
Ueno, Kosei
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Yang, Jinghuan
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Sun, Quan
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Aoyo, Daisuke
;
Yu, Han
The construction of metallic nanostructures with strong near-field enhancement is becoming increasingly significant for the practical use of plasmonic devices, such as plasmonic sensors and light-energy conversion systems. Importantly, the near-field enhancement effect depends on the plasmon dephasing time. Here, we propose a method for controlling plasmon dephasing time by utilizing plasmonic coupling for stronger near-field enhancement. Ordered arrays of stacked nanogap gold (Au) structures composed of a metal/insulator/metal nanostructure were fabricated by electron beam lithography and dry etching processes on a niobium-doped titanium dioxide substrate. The dark plasmon mode was excited by the near-field coupling between the upper and lower Au nanostructures separated by an alumina layer with a thickness of 15 nm. A strong near-field enhancement effect was induced by the localization of the electromagnetic field between the upper and lower Au nanostructures and the longer plasmon dephasing time based on the excitation of the dark plasmon mode. It is noteworthy that the dephasing time of the dark plasmon mode measured by time-resolved photoemission electron microscopy was extended 3-fold compared with that of the plasmon mode of the Au nanoblock, which can be controlled by the structural design of the stacked nanogap Au structures. (C) 2018 Elsevier Ltd. All rights reserved.
Adhesion and Material Properties Between Polyimide and Passivation Layers for Polymer/Metal Hybrid Bonding in 3-D Integration
(2019-03-01)
Lu, Cheng-Hsien
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Kho, Yi-Tung
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Chen, Chiao-Pei
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Tsai, Bin-Ling
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Chen, Kuan-Neng
This paper investigates polymer/metal hybrid bonding structure using conventional polyimide and modified polyimide-like material. Adhesion properties between bonding material and passivation layer were evaluated by four-point bending method, atomic force microscopy, water contact angle measurement, and X-ray photoelectron spectroscopy. Various annealing temperatures were applied to verify the reliability under thermal stress. The results show that the modified polyimide-like material with the curing temperature below 250 degrees C has better adhesion than the conventional polyimide. This modified polyimide material can be used in low-temperature hybrid bonding technology for advanced integration.
Influence of basal stacking faults on luminescence of m-plane Mg0.19Zn0.81O/ZnO quantum wells grown on a two-step MgZnO-buffer layer
(2019-03-01)
Wu, Yung-Chi
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Chang, Ning-An
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Yang, Tsung-Han
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Tsai, Chih-Ya
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Chen, Hou-Ren
Different well widths of m-plane Mg0.19Zn0.81O/ZnO multiple quantum wells (MQWs) have been fabricated on the two-step pregrown MgZnO-buffered m-plane sapphires by a pulsed laser deposition and have a narrower linewidth on x-ray diffraction than ZnO-buffered MQWs. By using the variation method to calculate the band diagram and by corroborating the results of temperature-dependent photoluminescence, we confirm the binding energies of free exciton and basal-stacking-fault-bound exciton, which is composed of electrons in the barrier and confined hole in the narrow-width MQWs. The coupling of A1(LO) phonon with excitons in m-MQWs shows more sensitivity toward a decrease in well width than E2(low), due to the crystal symmetry and the reduced Bohr radius. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE)
[2.2.2.2](2,7)-1-Bromonaphthalenophane from a Desymmetrized Building Block Bearing Electrophilic and Masked Nucleophilic Functionalities
(2019-03-01)
Cai, Guangke
;
Chatterjee, Shreyam
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Hisaki, Ichiro
;
Tobe, Yoshito
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應用化學系
In search of 2,7-ethylene-bridged naphthalenophanes with desymmetrized naphthalene cores as inherently chiral cyclophanes, nucleophilic substitution of 1-bromo-7-(bromomethyl)-2-[(trimethylsilyl)methyl]naphthalene, a desymmetrized building block bearing an electrophilic group (CH2Br) and a masked nucleophilic functionality (CH2TMS) which can be activated by fluoride anion, was examined. As a result, in contrast to the case of parent naphthalenophanes wherein the smallest [2.2]naphthalenophane was obtained as the major product, only [2.2.2.2](2,7)-1-bromonaphthalenophane was obtained albeit in low yields, whereas the corresponding [2.2]- or [2.2.2]naphthalenophanes were not obtained. Though the [2.2.2.2]-1-bromonaphthalenophane can adopt four idealized geometries of different symmetry, among which three are inherently chiral, theoretical calculations predict that three conformers have almost equal energy and may equilibrate in solution. The X-ray crystallographic study shows that it adopts a C-2 conformation with anti,anti,anti orientation of the C-Br bonds at least as a major component in crystal.
A Novel Stretch Energy Minimization Algorithm for Equiareal Parameterizations
(2019-03-01)
Yueh, Mei-Heng
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Lin, Wen-Wei
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Wu, Chin-Tien
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Yau, Shing-Tung
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應用數學系
Surface parameterizations have been widely applied to computer graphics and digital geometry processing. In this paper, we propose a novel stretch energy minimization (SEM) algorithm for the computation of equiareal parameterizations of simply connected open surfaces with very small area distortions and highly improved computational efficiencies. In addition, the existence of nontrivial limit points of the SEM algorithm is guaranteed under some mild assumptions of the mesh quality. Numerical experiments indicate that the accuracy, effectiveness, and robustness of the proposed SEM algorithm outperform the other state-of-the-art algorithms. Applications of the SEM on surface remeshing, registration and morphing for simply connected open surfaces are demonstrated thereafter. Thanks to the SEM algorithm, the computation for these applications can be carried out efficiently and reliably.
Major bleeding risk of endoscopic sphincterotomy versus endoscopic papillary balloon dilatation in hemodialysis patients
(2019-03-01)
Tsai, Ming-Chang
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Wang, Chi-Chih
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Wang, Yao-Tung
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Yang, Tzu-Wei
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Chen, Hsuan-Yi
Background/Aims: Endoscopic sphincterotomy (EST) and endoscopic papillary balloon dilatation (EPBD) are used for therapeutic endoscopic retrograde cholangiopancreatography (ERCP). The postprocedure bleeding rate for EPBD is low in the normal population; however, this bleeding rate in a group of patients prone to bleeding, such as patients with end-stage renal disease, is not well-established. We therefore evaluated the post-EST and post-EPBD bleeding rate among hemodialysis (HD) patients based on data from Taiwan's National Health Insurance Research Database (NHIRD). Patients and Methods: The NHIRD entries for a population of 2 million were screened for patients who had a catastrophic illness card for HD between 1st January 2004 and 31st December 2011 and these patients were enrolled as research subjects. The rates of major gastrointestinal tract bleeding events appearing within 14 days after EST or EPBD were compared between HD and non-HD patients. Results: A total of 3561 patients, over 18 years of age and without liver cirrhosis or hematologic diseases, underwent 3826 EST and 280 EPBD procedures during the 8 calendar years selected for our analysis. The total post-ERCP major bleeding rate was much higher in HD than in non-HD patients (8.64% vs. 2.16%, P < 0.0001). The rate of postprocedure major bleeding events was lower for non-HD patients who underwent EPBD than those who underwent EST (0.75% vs. 2.26%; P = 0.049), whereas the postprocedure major bleeding event rates were similar in HD patients who underwent either EPBD or EST (8.70% vs. 8.33%; P = 0.484). Conclusion: Post-ERCP, post-EST, and post-EPBD major bleeding rates were all higher in HD patients in this study. EPBD resulted in lower postprocedure major bleeding events than EST in the non-HD population, but it failed to provide the reduction in bleeding events needed to perform endoscopic hemostasis in HD patients.
The Development of CMOS Amperometric Sensing Chip with a Novel 3-Dimensional TiN Nano-Electrode Array
(2019-03-01)
Lien, Chun-Lung
;
Yuan, Chiun-Jye
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交大名義發表
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生物科技學系
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分子醫學與生物工程研究所
An electrochemical sensing chip with an 8 x 8 array of titanium nitride three-dimensional nano-electrodes (TiN 3D-NEA) was designed and fabricated via a standard integrated complementary metal oxide semiconductor process. Each nano-electrode in 3D-NEA exhibited a pole-like structure with a radius of 100 nm and a height of 35 nm. The numeric simulation showed that the nano-electrode with a radius of around 100 nm exhibited a more uniformly distributed electric field and a much higher electric field magnitude compared to that of the microelectrode. Cyclic voltammetry study with Ru(NH3)(6)(3+) also revealed that the TiN 3D-NEA exhibited a much higher current density than that obtained from the microelectrode by two orders of magnitude. Further studies showed that the electrocatalytical reduction of hydrogen peroxide (H2O2) could occur on a TiN 3D-NEA-based sensing chip with a high sensitivity of 667.2 mAmM(-1)cm(-2). The linear detection range for H2O2 was between 0.1 M and 5 mM with a lowest detection limit of 0.1 M. These results indicated that the fabricated TiN 3D-NEA exhibited high catalytic activity and sensitivity to H2O2 and could be a promising sensor for H2O2 measurement.
Ribose-5-phosphate isomerase A overexpression promotes liver cancer development in transgenic zebrafish via activation of ERK and beta-catenin pathways
(2019-03-01)
Chou, Yu-Ting
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Chen, Li-Yang
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Tsai, Shin-Lin
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Tu, Hsiao-Chen
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Lu, Jeng-Wei
Dysregulation of the enzymes involved in the pentose phosphate pathway (PPP) is known to promote tumorigenesis. Our recent study demonstrated that ribose-5-phosphate isomerase (RPIA), a key regulator of the PPP, regulates hepatoma cell proliferation and colony formation. Our studies in zebrafish reveal that RPIA-mediated hepatocarcinogenesis requires extracellular signal-regulated kinase (ERK) and beta-catenin signaling. To further investigate RPIA-mediated hepatocarcinogenesis, two independent lines of transgenic zebrafish expressing human RPIA in the liver were generated. These studies reveal that RPIA overexpression triggers lipogenic factor/enzyme expression, steatosis, fibrosis and proliferation of the liver. In addition, the severity of fibrosis and the extent of proliferation are positively correlated with RPIA expression levels. Furthermore, RPIA-mediated induction of hepatocellular carcinoma (HCC) requires the ERK and beta-catenin signaling pathway but is not dependent upon transaldolase levels. Our study presents a mechanism for RPIA-mediated hepatocarcinogenesis and suggests that RPIA represents a valuable therapeutic target for the treatment of HCC.
Standardization Status of Immersive Video Coding
(2019-03-01)
Wien, Mathias
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Boyce, Jill M.
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Stockhammer, Thomas
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Peng, Wen-Hsiao
;
資訊工程學系
Based on increasing availability of capture and display devices dedicated to immersive media, coding, and transmission of these media has recently become a highest-priority subject of standardization. Different levels of immersiveness are defined with respect to an increasing degree of freedom in terms of movements of the observer within the immersive media scene. The level ranges from three degrees of freedom allowing the user to look around in all directions from a fixed point of view to six degrees of freedom, where the user can freely alter the viewpoint within the immersive media scene. The moving pictures experts group (MPEG) of ISO/IEC is developing a standards suite on "Coded Representation of Immersive Media," called MPEG-I, to provide technical solutions for building blocks of the media transmission chain, ranging from architecture, systems tools, coding of video and audio signals, to point clouds and timed text. In this paper, an overview on recent and ongoing standardization efforts in this area is presented. While some specifications, such as high efficiency video coding or version 1 of the omnidirectional media format, are already available, other activities are under development or in the exploration phase. This paper addresses the status of these efforts with a focus on video signals, indicates the development timelines, summarizes the main technical details, and provides pointers to further points of reference.
Efficiency evaluation of a hybrid miniaturized concentrated photovoltaic for harvesting direct/diffused solar light
(2019-03-01)
Tsao, Wei-Chen
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Zeng, Qiu-Chun
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Yeh, Yu-Hsiang
;
Tsai, Chih-Hung
;
Hong, Hwen-Fen
In this paper, a miniaturized concentrator photovoltaic (CPV) system is experimentally demonstrated based on a hot embossing silicone lens array with a size of 2 cm x 2 cm. Owing to the small size of the lens array, the total track of the CPV system can be as small as 4 cm. Consequently, the weight of the CPV system can be much lower than conventional bulky CPV system. For harvesting the diffuse solar radiation, perovskite solar cells are mounted adjacent to a multi junction solar cell. Theoretically, the short-circuit current of the CPV system can be enhanced from 48.1 to 85.5 mA for gamma = 0.7. The enhancement can be much higher for off-normal incident light. This kind of hybrid CPV system will be useful for cloudy weather and also useful for compensating the loss caused by the miss-alignment of the tracking module.
【產學合作】科技部人工智慧普適研究中心107年度成果發表會
(國立交通大學資訊學院, 2019-03)
科技部人工智慧普適研究中心
科技部人工智慧普適研究中心(PAIR Labs) 於2018 年12 月28 日在新竹國立交通大學電資大樓舉行年度成果發表會，當日除了邀請科技部政務次長許有進博士與交通大學副校長林一平博士蒞臨指導外，也請到國內重要企業聯發科總經理陳志成以及國網中心主任陳添福到場進行演講與交流。發表會由中心17 個計畫團隊共同展出年度成果，除了各教授團隊報告與攤位擺設之外，更有四組計畫團隊透過Live Demo 展示研究成果。
Effects of Annealing on Ferroelectric Hafnium-Zirconium-Oxide-Based Transistor Technology
(2019-03-01)
Chen, Yi-Hsuan
;
Su, Chun-Jung
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Hu, Chenming
;
Wu, Tian-Li
;
國際半導體學院
In this letter, we investigate annealing effects in ferroelectric HfZrOx dielectric in metal-insulator-metal devices and metal-oxide-semiconductor capacitors by comparing two annealing methods: rapid thermal annealing (RTA) and microwave annealing (MWA). The tradeoff characteristics between the annealing conditions, polarization-electric field characteristics, gate leakage current, and interface state density (D-it) are discussed. We show that: 1) a positive correlation between the remanent polarization (Pr), the gate leakage current, and D-it as the annealing temperature (RTA) and the annealing power (MWA) increase and 2) the MWA is promising for ferroelectric transistors technology, since its low thermal budget can minimize D-it and avoid increase in the gate leakage current.
One Bipolar Selector-One Resistor for Flexible Crossbar Memory Applications
(2019-03-01)
Kumar, Dayanand
;
Aluguri, Rakesh
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Chand, Umesh
;
Tseng, Tseung-Yuen
;
電子工程學系及電子研究所
A bipolar, highly nonlinear n-p-n selector is coupled in series with resistive switching memory device to suppress the sneak path current. The memory characteristics are measured for the crossbar array fabricated on a flexible polyethylene terephthalate substrate. Dominant conduction mechanism is the Zener tunneling to obtain the high nonlinearity in the selector device. This phenomenon validates the I-V characteristics which are temperature dependent, which leads to decrease in the turn-on voltage of the device as the temperature increases. The proposed one bipolar selector-one resistor device demonstrates better memory characteristics with the high nonlinearity (similar to 10(3)), observable memory window of about one order, excellent ac endurance (10(7)) cycles, fast switching speed (60 ns), and stable retention (10(4) s) at 100 degrees C. The results show the substantial potential of the proposedone selector-one-resistor structure in suppressing the leakage current, making it attractive for future high-density flexible crossbar memory array.
【系所動態】資訊學院博士班培育產業觀點研究能力兼具高階人才
(國立交通大學資訊學院, 2019-03)
林珮雯
為促進國內產業界與學術合作，培育具有產業觀點且具備高等研究能力的博士人才，國立交通大學資訊學院於108 年8 月正式成立學院博士班。本博士班學生透過與企業合作，更加瞭解產業實作之技術需求及達到產業、學術間技術交流，藉由參與國際會議與國際接軌，有效提升學生之國際競爭力，此外同時協助合作企業提升核心技術，達到互惠雙贏局面。