Browsing by Issue Date, starting with "2019-07-03"

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Aging, cognition, and the brain: effects of age-related variation in white matter integrity on neuropsychological function
(2019-07-03)
Fan, Yang-Teng
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Fang, Ya-Wen
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Chen, Ya-Ping
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Leshikar, Eric D.
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Lin, Ching-Po
Alterations in brain structure are viewed as neurobiological indicators which are closely tied to cognitive changes in healthy human aging. The current study used diffusion tensor imaging (DTI) tractography to investigate the relationship between age, brain variation in white matter (WM) integrity, and cognitive function. Sixteen younger adults (aged 20-28 years) and 18 healthy older adults (aged 60-75 years) underwent DTI scanning and a standardized battery of neuropsychological measures. Behaviorally, older adults exhibited poorer performance on multiple cognitive measures compared to younger adults. At the neural level, the effects of aging on theWM integrity were evident within interhemispheric (the anterior portion of corpus callosum) and transverse (the right uncinate fasciculus) fibers of the frontal regions, and the cingulum-angular fibers. Our correlation results showed that age-related WM differentially influenced cognitive function, with increased fractional anisotropy values in both the anterior corpus callosum and the right cingulum/angular fibers positively correlated with performance on the visuospatial task in older adults. Moreover, mediation analysis further revealed that the WM tract integrity of the frontal interhemspheric fibers was a significant mediator of age-visuospatial performance relation in older adults, but not in younger adults. These findings support the vulnerability of the frontal WM fibers to normal aging and push forward our understanding of cognitive aging by providing a more integrative view of the neural basis of linkages among aging, cognition, and brain.
Investor Attention and Stock Price Movement
(2019-07-03)
Cheng, Chiao-Ming
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Huang, Alex YiHou
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Hu, Ming-Che
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交大名義發表
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資訊管理與財務金融系註：原資管所+財金所
Prior studies have documented that information presence (absence) leads to price continuation (reversal) when a stock price experiences extreme shock. The authors investigate whether the level of investor attention have an impact on stock price dynamics following the shock. They show that when shocks are not accompanied by new information, the price generally reverses, and the magnitude of the reversal is stronger for stocks with lower degree of investor attention. The asymmetric effect on the magnitude of reversal is stronger for stock with higher return volatility. In addition, for the price shocks accompanied by new information, stock price would continue for a short run, and such continuation is statistically significant and stronger when investors are optimistic toward to the stocks.
Clarification of lower bounds of two-machine flow-shop scheduling to minimize total late work
(2019-07-03)
Blazewicz, Jacek
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Chen, Xin
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Lee, Richard C. T.
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Lin, Bertrand M. T.
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Lin, Feng-Cheng
A systematic and efficient simulation scheme for the Greeks of financial derivatives
(2019-07-03)
Lyuu, Yuh-Dauh
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Teng, Huei-Wen
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Tseng, Yao-Te
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Wang, Sheng-Xiang
;
統計學研究所
Greeks are the price sensitivities of financial derivatives and are essential for pricing, speculation, risk management, and model calibration. Although the pathwise method has been popular for calculating them, its applicability is problematic when the integrand is discontinuous. To tackle this problem, this paper defines and derives the parameter derivative of a discontinuous integrand of certain functional forms with respect to the parameter of interest. The parameter derivative is such that its integration equals the differentiation of the integration of the aforesaid discontinuous integrand with respect to that parameter. As a result, unbiased Greek formulas for a very broad class of payoff functions and models can be systematically derived. This new method is applied to the Greeks of (1) Asian options under two popular Levy processes, i.e. Merton's jump-diffusion model and the variance-gamma process, and (2) collateralized debt obligations under the Gaussian copula model. Our Greeks outperform the finite-difference and likelihood ratio methods in terms of accuracy, variance, and computation time.
An analytical closed-form solution for multiple line supplier selection problem
(2019-07-04)
Pearn, W. L.
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Tai, Y. T.
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Tseng, S. C.
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工業工程與管理學系
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Department of Industrial Engineering and Management
Supplier selection is an essential issue, particularly, for semiconductor manufacturing. Nowadays, since high demands in the globally competitive semiconductor manufacturing environment, multiple-line processes are quite commonly applied. In the paper, we consider a two-stage method composing of quality verification and selection decision for multiple-line supplier selection problems. Since quality performance is an important criterion in supplier selection, we test whether the new supplier has a significantly better capability than the existing supplier based on the multiple-line yield index in the stage of quality verification. In selection decision, when the magnitude of capability outperformance is significant, switching contracts to a new entrant supplier is suggested. In addition, analytical closed-form solutions for asymptotical critical values and required sample sizes are derived and tabulated for the investigated multiple-line supplier selection problem. We demonstrate the applicability of the proposed supplier selection method by presenting a real-world example taken from a semiconductor packaging shop floor located in the Science-based Industrial Park in Hsinchu, Taiwan.
Deviatoric deformation kinetics in high entropy alloy under hydrostatic compression
(2019-07-05)
Huang, E-Wen
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Lin, Chih-Ming
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Juang, Jenh-Yih
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Chang, Yao-Jen
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Chang, Yuan-Wei
An equiatomic CoCrFeMnNi high-entropy alloy under hydrostatic compression is investigated using insitu angular-dispersive X-ray diffraction to explore the polymorphism in high entropy alloy systems. The metallic system is of face-centered-cubic structure at ambient condition and applied hydrostatic pressures up to 20 GPa via diamond anvil cell. The angle-resolved diffraction-intensity evolutions of multiple diffraction peaks were collected simultaneously to elucidate the phase stability examinations. The phase transformation from face-centered-cubic to hexagonal-close-packed structure was evidently observed in CoCrFeMnNi alloy accompanied by a deviatoric strain subjected to the hydrostatic compression. We found lattice-asymmetric crossover before and after the phase transformation subjected to hydrostatic compression surroundings. Deviatoric strain triggers fcc-hcp phase transformation as local heterogeneity-driven lattice distortion is significant for CoCrFeMnNi alloy. (c) 2019 The Authors. Published by Elsevier B.V.
Polysubstituted Hexa-cata-hexabenzocoronenes: Syntheses, Characterization, and Their Potential as Semiconducting Materials in Transistor Applications
(2019-07-05)
Kumar, Sushil
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Pola, Someshwar
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Huang, Chih-Wei
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Islam, Md. Minarul
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Venkateswarlu, Samala
A series of tetra- and octa-substituted hexa-cata-hexabenzocoronenes (cata-HBCs) were synthesized from tetraryl olefins via iodine- and iron chloride-catalyzed oxidative cyclodehydrogenation reactions. The substitutions on the periphery of the parent HBC serve to modify the photophysical properties, highest occupied molecular orbital-lowest unoccupied molecular orbital gaps, and thermal stabilities of the respective derivatives. The crystal structures were determined to display multiple twists in the framework, resulting in different packing motifs depending on the position, type, and number of functional groups on the hexabenzocoronene framework. Nearly perfect co-facial packing to marginally or extensively shifted co-facial stacks were obtained due to substitution. The single crystals of parent HBC were used to fabricate single-crystal field-effect transistors, from which the highest p-channel mobility of 0.51 cm(2) V-1 s(-1) was measured. Thin-film transistors of selected HBCs were also prepared, and 0.61 cm(2) V-1 s(-1) was obtained for MeHBC-2. These results attest the potential of these materials as semiconducting materials.
A silicon-based coral-like nanostructured microfluidics to isolate rare cells in human circulation: validation by SK-BR-3 cancer cell line and its utility in circulating fetal nucleated red blood cells
(2019-07-05)
Huang, Chung-Er
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Chen, Ming
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交大名義發表
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National Chiao Tung University
Thermally-enhanced current gain of quantum-well heterojunction bipolar transistor
(2019-07-07)
Chang, Yun-Hsuan
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Chou, Yung-Lin
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Chang, Shu-Wei
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Wu, Chao-Hsin
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光電工程學系
We investigate the current gain of quantum-well heterojunction bipolar transistors (QW-HBTs) under different operation temperatures. It is experimentally shown that the introduction of a QW into the base region of HBTs results in an increasing current gain with the temperature, which is a behavior opposite to that of typical HBTs. An enhancement of current gain around 226% is observed as the temperature of QW-HBT is raised from 35 to 95 degrees C. This unusual trend is mainly attributed to the shorter escape time of electrons in the QW at the higher temperature. A modified charge-control model based on thermionic emissions of electrons in the QW region is constructed to model this temperature-dependent phenomenon, and the result agrees well with our experimental observations.
On-Surface Evolution of meso-Isomerism in Two-Dimensional Supramolecular Assemblies
(2019-07-08)
Park, Juyeon
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Kim, Ju-Hyung
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Bak, Sunmi
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Tahara, Kazukuni
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Jung, Jaehoon
Chiral structures created through the adsorption of molecules onto achiral surfaces play pivotal roles in many fields of science and engineering. Here, we present a systematic study of a novel chiral phenomenon on a surface in terms of organizational chirality, that is, meso-isomerism, through coverage-driven hierarchical polymorphic transitions of supramolecular assemblies of highly symmetric pi-conjugated molecules. Four coverage-dependent phases of dehydrobenzo[12]annulene were uniformly fabricated on Ag(111), exhibiting unique chiral characteristics from the single-molecule level to two-dimensional supramolecular assemblies. All coverage-driven phase transitions stem from adsorption-induced pseudo-diastereomerism, and our observation of a lemniscate-type (infinity) supramolecular configuration clearly reveals a drastic chiral phase transition from an enantiomeric chiral domain to a meso-isomeric achiral domain. These findings provide new insights into controlling two-dimensional chiral architectures on surfaces.
Modeling knowledge sharing and team performance The interactions of ethical leadership and ambidexterity with politics and job complexity
(2019-07-08)
Liu, Min-Ling
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Lin, Chieh-Peng
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Joe, Sheng-Wuu
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Chen, Kuang-Jung
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經營管理研究所
Purpose To deepen our understanding about the development of team performance, the purpose of this paper is to develop a model that explains how ambidexterity and ethical leadership affect knowledge sharing and team performance through within-team competition. Design/methodology/approach This study demonstrates the applicability of ambidexterity and within-team competition by surveying 78 teams from the high-tech and banking industries. This study further presents a three-way interaction among ambidexterity, politics and job complexity. Findings This study finds that both ambidexterity and ethical leadership are positively related to knowledge sharing and team performance through the mediation of team development competition. Originality/value This study confirms that ambidexterity and ethical leadership play critical factors for improving knowledge sharing and team performance through the mediation of team development competition. Furthermore, the moderating effects of politics and job complexity are also confirmed in the research.
Multiple Pleomorphic Tetramers of Thermostable Direct Hemolysin from Grimontia hollisae in Exerting Hemolysis and Membrane Binding
(2019-07-08)
Wang, Yu-Kuo
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Huang, Sheng-Cih
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Chang, Chin-Yuan
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Huang, Wan-Ting
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Liao, Man-Jun
Oligomerization of protein into specific quaternary structures plays important biological functions, including regulation of gene expression, enzymes activity, and cell-cell interactions. Here, we report the determination of two crystal structures of the Grimontia hollisae (formally described as Vibrio hollisae) thermostable direct hemolysin (Gh-TDH), a pore-forming toxin. The toxin crystalized in the same space group of P2(1)2(1)2, but with two different crystal packing patterns, each revealing three consistent tetrameric oligomerization forms called Oligomer-I, -II, and -III. A central pore with comparable depth of similar to 50 angstrom but differing in shape and size was observed in all determined toxin tetrameric oligomers. A common motif of a toxin dimer was found in all determined structures, suggesting a plausible minimum functional unit within the tetrameric structure in cell membrane binding and possible hemolytic activity. Our results show that bacterial toxins may form a single or highly symmetric oligomerization state when exerting their biological functions. The dynamic nature of multiple symmetric oligomers formed upon release of the toxin may open a niche for bacteria survival in harsh living environments.
Dual-focal-plane augmented reality head-up display using a single picture generation unit and a single freeform mirror
(2019-07-10)
Qin, Zong
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Lin, Shih-Ming
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Lu, Kuang-Tso
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Chen, Cheng-Huan
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Huang, Yi-Pai
Two or more focal planes are required in augmented reality head-up displays (AR HUDs) to respectively present basic and interactive driving information to car drivers; whereas, solutions using two separated picture generation units (PGUs) with two sets of optics incur increased cost, reduced reliability, and expanded volume. To develop an AR HUD using a single PGU and a single curved mirror, we propose to set two logically separated regions on a single PGU and optically relay one of them to a new position to create two focal planes. A single freeform mirror acquired through careful optical and mechanical design optimization produces high image quality in an eyebox of 120 mm by 60 mm, simultaneously for a far image (9 m, 10 degrees by 3 degrees) and a near image (2.5 m, 6 degrees by 2 degrees). Finally, an AR HUD product with a compact volume of 8.5 L is fabricated to experimentally verify the design. (C) 2019 Optical Society of America
【高雄市陽明大學校友會】～第二屆第一次會員大會
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組
高雄市陽明大學校友會──108年上半年精彩活動花絮
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組
106年成立至今舉辦多項活動及聯誼餐會，今年將邁入第2屆，8月18日將擴大舉行會員聯誼大會，歡迎南下高雄參與年度盛會！
陽明大學牙醫校友總會──陽明牙醫診所12週年暨陽明格子兒童青少年牙醫診所開幕
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組
適逢陽明牙醫診所歡慶成立12週年，位於隔壁棟的陽明格子青少年牙醫診所亦熱鬧開幕，郭校長及多位貴賓師長皆到場慶祝！
【校友總會】～竹竹苗校友聯誼餐會
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組
陽明、哈佛共同栽培，一圓嘉中林晉毅醫師夢
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組
錄取哈佛大學的嘉義高中應屆畢業生林晉毅即將赴美，陽明7月2日宣布將與哈佛大學共同培育人才，除了將協助林晉毅保留陽明的學籍外...
微免所暑期課程擴大辦理，越南孫德勝大學專班研習最新微生物科技
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組
專為外籍生開設的「微生物科技與新藥研發」暑期課程，由於學員反應良好，除原有來自姊妹校學員20多名，今年擴大另為越南孫德勝大...
【陽明大學牙醫校友總會】～台大陽明校友大會暨全球四所頂尖大學華山論劍
(國立陽明大學, 2019-07-11)
陽明電子報編輯小組