Browsing by Issue Date, starting with "2019-11-08"

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Enhancing the Seebeck effect in Ge/Si through the combination of interfacial design features
(2019-11-08)
Nadtochiy, Andriy
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Kuryliuk, Vasyl
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Strelchuk, Viktor
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Korotchenkov, Oleg
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Li, Pei-Wen
Due to their inherent physical properties, thin-film Si/SiGe heterostructures have specific thermal management applications in advanced integrated circuits and this in turn is essential not only to prevent a high local temperature and overheat inside the circuit, but also generate electricity through the Seebeck effect. Here, we were able to enhance the Seebeck effect in the germanium composite quantum dots (CQDs) embedded in silicon by increasing the number of thin silicon layers inside the dot (multi-fold CQD material). The Seebeck effect in the CQD structures and multi-layer boron atomic layer-doped SiGe epitaxial films was studied experimentally at temperatures in the range from 50 to 300 K and detailed calculations for the Seebeck coefficient employing different scattering mechanisms were made. Our results show that the Seebeck coefficient is enhanced up to approximate to 40% in a 3-fold CQD material with respect to 2-fold Ge/Si CQDs. This enhancement was precisely modeled by taking into account the scattering of phonons by inner boundaries and the carrier filtering by the CQD inclusions. Our model is also able to reproduce the observed temperature dependence of the Seebeck coefficient in the B atomic layer-doped SiGe fairly well. We expect that the phonon scattering techniques developed here could significantly improve the thermoelectric performance of Ge/Si materials through further optimization of the layer stacks inside the quantum dot and of the dopant concentrations.
搖你千遍也不厭倦！別再喝含糖飲料了
(2019-11-10)
石恩亞
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Department of Communication and Technology
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傳播與科技學系
台灣人愛喝手搖杯，飲料店密集為全球之冠，國內外多項研究報告顯示，如果每日喝超過2杯含糖飲品者容易早逝，原因大多為心血管疾病、糖尿病、癌症，警告飲料不離手的人們「喝越多，死越快」。
Face ID是進步還是危機？
(2019-11-10)
陳婉宣
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Department of Communication and Technology
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傳播與科技學系
人臉辨識系統象徵著科技的進步，帶來了無限的可能性。但怎麼使用？用在哪裡？是否會造成不同的影響？本文討論人臉辨識系統的應用及威脅。
數位脫單路——交友軟體的安全性與法規爭議
(2019-11-10)
陳姝芸
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Department of Communication and Technology
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傳播與科技學系
使用交友軟體已成為現代人普遍交友管道之一，然而其造成的犯罪問題、消費者權益侵犯與目前尚未完備的相關法規，始終是社會上不容忽視的議題。
我們正在變成塑膠人？塑膠污染的反噬
(2019-11-10)
李芝謙
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Department of Communication and Technology
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傳播與科技學系
塑膠污染早已是舊聞，但你知道吃進塑膠的動物，不只有海鳥和海龜，人類也開始吃塑膠了嗎？研究發現，人們一年大約食入5萬個塑膠微粒，而這還只是冰山一角而已！
總編輯的話
(2019-11-10)
黃心姵
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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323期，共計8篇文章，包含三篇社會議題、四篇科技新知、一篇人物特寫。本篇頭題為王會瑄的〈網紅旋風席捲　吃什麼誰說了算？〉。本期文章多探討當科技日新月異，生活越便利的同時，隨之產生的社會問題。
網紅旋風席捲　吃什麼誰說了算？
(2019-11-10)
王會瑄
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Department of Communication and Technology
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傳播與科技學系
身處在這個高度依賴搜索引擎的消費時代，在口碑經濟的浪潮下，網紅如何影響我們的購物決策，又將帶領我們的飲食健康走向何方呢？
要讓台南家鄉味「鍋燒意麵」飄香國際－Waa Wei
(2019-11-10)
蕭蕙崎
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Department of Communication and Technology
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傳播與科技學系
鍋燒意麵是台灣獨一無二的麵食文化，Waa Wei透過一碗碗的鍋燒意麵，立足台灣、放眼世界。
當個夜貓子，對大腦有甚麼影響？
(2019-11-10)
李旻珊
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Department of Communication and Technology
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傳播與科技學系
只是晚睡而已，為甚麼補了眠還是那麼累？不只要睡得夠，更需要「睡對時間」。
心碎喝酒，越常喝越「心痛」！酒精是敵還是友？
(2019-11-10)
施詞萱
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Department of Communication and Technology
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傳播與科技學系
一天一小杯，看似無害又是許多人放鬆的方法。但是有研究指出，頻繁地喝酒相比久久一次喝到爛醉，更會影響健康問題！到底喝酒對於人體而言是敵？還是友呢？
Significant predictive factors of the severity and outcomes of the first attack of acute angioedema in children
(2019-11-11)
Syue, Yuan-Jhen
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Li, Chao-Jui
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Chen, Wen-Liang
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Lee, Tsung-Han
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Huang, Cheng-Chieh
Background The initial episode of angioedema in children can be potential life-threatening due to the lack of prompt identification and treatment. We aimed to analyze the factors predicting the severity and outcomes of the first attack of acute angioedema in children. Methods This was a retrospective study with 406 children (< 18 years) who presented in the emergency department (ED) with an initial episode of acute angioedema and who had subsequent follow-up visits in the out-patient department from January 2008 to December 2014. The severity of the acute angioedema was categorized as severe (requiring hospital admission), moderate (requiring a stay in the short-term pediatric observation unit [POU]), or mild (discharged directly from the ED). The associations among the disease severity, patient demographics and clinical presentation were analyzed. Result In total, 109 (26.8%) children had severe angioedema, and the majority of those children were male (65.1%). Most of the children were of preschool age (56.4%), and only 6.4% were adolescents. The co-occurrence of pyrexia or urticaria, etiologies of the angioedema related to medications or infections, the presence of respiratory symptoms, and a history of allergies (asthma, allergic rhinitis) were predictors of severe angioedema (all p < 0.05). Finally, the duration of angioedema was significantly shorter in children who had received short-term POU treatment (2.1 +/- 1.1 days) than in those who discharged from ED directly (2.3 +/- 1.4 days) and admitted to the hospital (3.5 +/- 2.0 days) (p < 0.001). Conclusion The co-occurrence of pyrexia or urticaria, etiologies related to medications or infections, the presence of respiratory symptoms, and a history of allergies were predictors of severe angioedema. More importantly, short-term POU observation and prompt treatment might be benefit for patients who did not require hospital admission.
Effects of TiO2 and SDC addition on the properties of YSZ electrolyte
(2019-11-12)
Shen, Chin-Tien
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Lee, Kan-Rong
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Hsieh, Yu-Pin
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Lee, Sheng-Wei
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Chang, Jeng-Kuei
In this study, we investigate the effects of adding titanium dioxide (TiO2) and samarium doped cerium oxide (SDC) on the properties of yttrium-stabilized zirconia (YSZ) electrolyte. The microstructure, mechanical, and electrochemical properties of the electrolyte are investigated. The performance in CO2 electrolysis is measured by supplying carbon dioxide to Ni-YSZ electrode and nitrogen to LSM electrode. Results show that TiO2 and SDC addition can reduce the sintering temperature and increase grain size. The ionic conductivity is 0.123 S cm(-1) at 1000 degrees C. In addition, the thermal expansion coefficient at 1000 degrees C is 8.25 x 10(-6)K(-1). The current density of the cell is 439 mA cm(-2) at 1.3 V and 1000 degrees C in solid oxide electrolysis cell. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Morphological and Molecular Defects in Human Three-Dimensional Retinal Organoid Model of X-Linked Juvenile Retinoschisis
(2019-11-12)
Huang, Kang-Chieh
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Wang, Mong-Lien
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Chen, Shih-Jen
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Kuo, Jean-Cheng
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Wang, Won-Jing
X-linked juvenile retinoschisis (XLRS), linked to mutations in the RS1 gene, is a degenerative retinopathy with a retinal splitting phenotype. We generated human induced pluripotent stem cells (hiPSCs) from patients to study XLRS in a 3D retinal organoid in vitro differentiation system. This model recapitulates key features of XLRS including retinal splitting, defective retinoschisin production, outer-segment defects, abnormal paxillin turnover, and impaired ER-Golgi transportation. RS1 mutation also affects the development of photoreceptor sensory cilia and results in altered expression of other retinopathy-associated genes. CRISPR/Cas9 correction of the disease-associated C625T mutation normalizes the splitting phenotype, outer-segment defects, paxillin dynamics, ciliary marker expression, and transcriptome profiles. Likewise, mutating RS1 in control hiPSCs produces the disease-associated phenotypes. Finally, we show that the C625T mutation can be repaired precisely and efficiently using a base-editing approach. Taken together, our data establish 3D organoids as a valid disease model.
Minimizing machine assignment costs over Delta-approximate solutions of the scheduling problem P parallel to C-max
(2019-11-12)
Kononov, A. V.
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Kovalyov, M. Y.
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Lin, B. M. T.
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資訊管理與財務金融系註：原資管所+財金所
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Department of Information Management and Finance
Bi-criteria lexicographical minimization problems with the makespan as the primary objective and the total machine assignment costs as the secondary objective have been recently introduced to the scheduling research, and polynomial time (r + 1, 1)-approximation algorithms have been suggested for their solution, where 1 < r < 2 is the performance ratio of an approximation algorithm for P parallel to C-max. We improve these results by presenting a polynomial time (1.5r - 1, 1)-approximation algorithm for the additive cost type. Then, we introduce a problem of minimizing the total machine assignment cost over the Delta-approximate solutions of the makespan minimization problem. We prove that this new problem is strongly NP-hard and pseudo-polynomially non-approximable in general. A polynomial time approximation algorithm with a guaranteed approximation ratio is presented for the additive cost type and bounded ratio between the maximal and minimal machine costs. An O (mn(2k)) time dynamic programming algorithm is also presented, where k is the fixed number of distinct job processing times. (C) 2019 Elsevier B.V. All rights reserved.
Composition Modulation of Ionic Liquid Hybrid Electrolyte for 5 V Lithium-Ion Batteries
(2019-11-13)
Wu, Chia-Jung
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Rath, Puma Chandra
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Patra, Jagabandhu
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Bresser, Dominic
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Passerini, Stefano
Electrolyte is a key component in high-voltage lithium-ion batteries (LIBs). Bis(trifluoromethanesulfonyl)imide-based ionic liquid (IL)/organic carbonate hybrid electrolytes have been a research focus owing to their excellent balance of safety and ionic conductivity. Nevertheless, corrosion of Al current collectors at high potentials usually happens for this kind of electrolyte. In this study, this long-standing problem is solved via the modulation of the IL/carbonate ratio and LiPF6 concentration in the hybrid electrolyte. The proposed electrolyte suppresses Al dissolution and electrolyte oxidation at 5 V (vs Li+/Li) and thus allows for ideal lithiation/delithiation performance of a high-voltage LiNi0.5Mn1.5O4 (LNMO) cathode even at 55 degrees C. The underlying mechanism is examined in this work. Excellent cycling stability (97% capacity retention) for an LNMO cathode after 300 cycles is achieved. This electrolyte shows good wettability toward a polyethylene separator and low flammability. In addition, satisfactory compatibility with both graphite and Si-based anodes is confirmed. The proposed electrolyte design strategies have great potential for applications in high-voltage LIBs.
Role of precursors mixing sequence on the properties of CoMn2O4 cathode materials and their application in pseudocapacitor
(2019-11-14)
Pattanayak, Bhaskar
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Simanjuntak, Firman Mangasa
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Panda, Debashis
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Yang, Chih-Chieh
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Kumar, Amit
In this study, the effect of oxygen vacancy in the CoMn2O4 on pseudocapacitive characteristics was examined, and two tetragonal CoMn2O4 spinel compounds with different oxygen vacancy concentrations and morphologies were synthesized by controlling the mixing sequence of the Co and Mn precursors. The mixing sequence was changed; thus, morphologies were changed from spherical nanoparticles to nanoflakes and oxygen vacancies were increased. Electrochemical studies have revealed that tetragonal CoMn2O4 spinels with a higher number of oxygen vacancies exhibit a higher specific capacitance of 1709 F g(-1) than those with a lower number of oxygen vacancies, which have a higher specific capacitance of 990 F g(-1). Oxygen vacancies create an active site for oxygen ion intercalation. Therefore, oxidation-reduction reactions occur because of the diffusion of oxygen ions at octahedral/tetrahedral crystal edges. The solid-state asymmetric pseudocapacitor exhibits a maximum energy density of 32 Wh.kg(-1) and an excellent cyclic stability of nearly 100%.
Formation Mechanism and Fluorescence Characterization of a Transient Assembly of Nanoparticles Generated by Femtosecond Laser Trapping
(2019-11-14)
Chiang, Wei-Yi
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Chen, Jim Jui-Kai
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Usman, Anwar
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Kudo, Tetsuhiro
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Xia, Kangwei
Femtosecond (fs) laser trapping of dielectric nanoparticles displays a unique trapping and directional ejection phenomenon, which is never observed in continuous-wave (cw) laser trapping. We studied the fs laser trapping and considered its dynamics and mechanism in terms of gathering, association, and ejection of nanoparticles. By tuning solution viscosity through adding ethylene glycol, the trapping behavior by fs and cw lasers are examined and compared with each other. The viscous solution slows down the diffusional and rotational movement of nanoparticles and increases the chance of nanoparticle assembly in the trapping site, which eventually leads to the novel ejection. We took advantage of fluorescence measurement to confirm the formation of the nanoparticle assembly during fs laser trapping. A red emission irregularly appeared in the fluorescence supports the transient assembly formation in the molecular level.
Optimal Design of a New Strain-Type Sensor for Cuff-Less Blood Pressure Measurement via Finite Element Modeling and Taguchi Method
(2019-11-15)
Tu, Tse-Yi
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Chao, Paul C-P
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電機工程學系
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電控工程研究所
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Department of Electrical and Computer Engineering
A new cuff-less blood pressure (BP) sensor is designed and optimized in this paper. This BP sensor is in a shape of a circular disc of polymer enclosing an electrode. As the sensor is attached to the wrist artery, the dynamic bending of the sensor due to small artery pulsation induces variation in the electrode strain, and then, its resistance varies. With adequate amplification to sense resistance variation, the pulsation signals can be successfully obtained. With the measured pulsation representing well the blood volume pulsation (BVP), BP can be estimated next via the pulse wave velocity (PWV) theory. Effort is dedicated by this paper to optimize the sizes and geometry of the proposed sensor to maximize the electrode curvature change for largest measured signal-to-noise ratio (SNR) possible, which maximizes the accuracy of BP estimation. To this end, the optimization via the finite element modeling and the Taguchi method is carried out. In results, the optimal sizes in height/radius, fillet, hardness, and the electrode position of the polymer disc are successfully derived, which are in the height of 2 mm, the radius of 6mm, the distance between the planar electrode and the bottom surface of sensor being 1 mm, the hardness of the encapsulating polymer being 25 in shore A hardness, and the fillets at the bottom of the polymer disc being 1 mm in radii. BP is measured for 59 subjects. The resulted errors are 3.60 +/- 5.40 mmHg (mean difference +/- standard deviation) and 1.15 +/- 1.63 mmHg for SBP and DBP, respectively. The correlations are 0.8787 and 0.9648, demonstrating well the favorable performance of the developed sensor.
【自煮時代：宿舍廚房改造願景工作坊】（一學分）
(國立陽明大學, 2019-11-15)
陽明電子報編輯小組
樂生首次院外展，珍貴公衛史料重現陽明
(國立陽明大學, 2019-11-15)
陽明電子報編輯小組
經過半年多籌畫，並獲得許多陽明校友捐款支持，藝文中心2019壓軸強檔──【樂生在陽明：醫病、生活文物展】10月31日揭幕，這也是...