Browsing by Issue Date, starting with "2019-01-04"

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Miscible density-driven flows in heterogeneous porous media: Influences of correlation length and distribution of permeability
(2019-01-04)
Li, Qian
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Cai, Weihua
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Li, Feng-Chen
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Li, Bingxi
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Chen, Ching-Yao
A random process and highly accurate pseudospectral method associated with compact finite differences are incorporated to evaluate effects of permeability heterogeneity to gravity-driven miscible porous media flows. Flows in heterogeneous permeability fields, based on multiple sets of random realizations with identical statistical characteristics, are simulated to elucidate the global trend of mean quantities and local variations. The presence of heterogeneity provokes more prominent fingering competition and greater variation of fingers' widths, hence the mean values of interested quantitative measures, i.e., breakthrough time, amount of fluid volumes transported, and normalized mixing effectiveness, are generally reduced. Resonant effects, whose influences on the flow fields are the most significant, are verified to occur in an intermediate correlation length, in which the widths of fingers are slightly less than the correspondent correlation length. Nevertheless, under the resonant conditions these measures are the most widely scattered between different random realizations associated with the same control parameters. The widest scatterings are mainly because of the enhancing sensitivity of flow path selections under such resonant conditions, especially in a few realizations whose high or low permeability regions align along with or transverse to the main flow direction. The significant scatterings of these quantitative measures, which had drawn little attention previously, suggest more cautious treatments for practical implementations in the regime of resonant effects.
看見土地的關懷－賴唐鴉與高沁余
(國立交通大學傳播與科技學系, 2019-01-04)
黃昱晉
賴唐鴉與高沁余（簡稱唐鴉與唐婆）兩人所經營的家庭美術館，有別於一般美術館的莊嚴，在這裡更多了些樸實的親切感。除了能欣賞到賴唐鴉的藝術創作外，也能在漫步在果園內享受天然的薰陶，另外還許多排列劃一的陶缸，裡頭正在釀製遠近馳名的唐婆醋，夫妻倆希望能分別靠著身為藝術家與科學家的專業，在各自截然不同的領域喚起人們對土地關懷的認知。
Emerging Organic and Organic/Inorganic Hybrid Photovoltaic Devices for Specialty Applications: Low-Level-Lighting Energy Conversion and Biomedical Treatment
(2019-01-04)
Chen, Fang-Chung
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交大名義發表
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光電工程學系
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National Chiao Tung University
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Department of Photonics
This article reviews the progress made in emerging photovoltaic devices, including dye-sensitized solar cells, organic solar cells, and perovskite solar cells, for specialty applications. Because they all feature tunable band structures, which can be modified through molecular design and/or altered compositions, the properties of emerging photovoltaic devices can be tailored to fit the special requirements of a particular application. For instance, they can be designed according to the emission spectrum of an artificial light source (e.g., fluorescence lamp and white light-emitting diode), thereby efficiently converting the indoor lighting to electricity. Furthermore, because there exists a near-infrared windowranging from 650 to 1350 nmin which photons can penetrate deeply into tissues, the absorption bands of these photovoltaic devices can be tailored specially to this therapeutic window to harvest tissue-penetrating light, thereby wirelessly providing power to biomedical devices positioned beneath the skin. The rapid progress made in these two representative areas suggests further promising applications of such emerging photovoltaic devices.
當食農碰到教育──內城生態學校
(國立交通大學傳播與科技學系, 2019-01-05)
楊巧柔
兩位宜蘭人賴志政與黃勝宏創立了「內城生態學校」。將社區跟周邊區域的配合，把社區的文化、歷史、人文帶進來。配合內城社區鐵牛車，先繞完認識社區以及阿公阿嬤輩以前在內城的記憶，認識完整個內城區域之後，再去生態學校，做農村實在的體驗。
讓產地與消費者更近的橋樑
(國立交通大學傳播與科技學系, 2019-01-05)
洪儷娟
曹育銓與自己的團隊搭建了一個生產者與消費者之間的橋梁－－bigreeny 料理．家，讓那些被用心生產的食材可以呈現在你眼前的杯盤茶具中，連結產地與消費者的菜單應運而生。
阿爸的米：田埂間的堅持與熱忱
(國立交通大學傳播與科技學系, 2019-01-05)
郭庭芸
宜蘭縣員山鄉內城，一個令人心曠神怡的鄉間社區。通稱螞蟻大哥，於2017受農委會獲選為第四屆百大青農的曾繁宜先生，分享一個在台北長大的青年怎麼投身友善農業，以及他至今六年多的務農故事中的酸甜苦辣。
博幼基金會　讓知識帶希望回家
(國立交通大學傳播與科技學系, 2019-01-05)
呂靜沅
博幼基金會成立於2002年，至今在台灣已經有18個課輔中心。成立的目的是希望可以用因材施教的方式，幫助弱勢家庭的孩童學習。
歐怡伶　不麻煩別人的環保推廣者
(國立交通大學傳播與科技學系, 2019-01-06)
陳子與
新村小商號誕生在新竹，它主打購物無包裝的理念，邀請前來的客人自備容器，如此一來便能減少塑膠袋垃圾。新村小商號並沒有非要賣什麼東西不可，因為打從一開始，歐怡伶就只是想示範一個天然的生活方式。
Exploring the ultrafast dynamics of a diarylethene derivative using sub-10 fs laser pulses
(2019-01-07)
Jarota, Arkadiusz
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Pastorczak, Ewa
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Tawfik, Walid
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Xue, Bing
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Kania, Rafal
A diarylethene derivative, 1,2-bis(2,4-dimethyl-5-phenyl-3-thienyl)perfluorocyclopentene (DMP), is a photoswitch molecule utilizing a reversible aromatic ring-opening reaction. The quantum yield of the ring-opening reaction is however remarkably low. We investigate the origin of this behaviour by means of ultrafast transient absorption spectroscopy utilizing sub-10 fs pulses, which is an invaluable tool for simultaneously studying both the electronic and the vibrational molecular dynamics. Namely, a noncollinear optical parametric amplifier (NOPA) generating sub-10 fs pulses in the spectral range 605-750 nm is employed. The transient absorption signal is modulated by several vibrational modes, which are compared with experimental and computational Raman spectra and then assigned to the ground or excited electronic state. We observe that the most pronounced vibrational mode - the ethylenic stretching mode at a frequency of 1501 cm(-1) - exhibits instantaneous frequency and amplitude modulation. The observed modulations occur due to weak coupling with another 1431 cm(-1) stretching mode mediated by a vibrational mode of low frequency, i.e. around 60 cm(-1). Fast internal conversion S-1 S-0 originates in a relaxation through a conical intersection (found by density-functional theory computations), facilitated by the two aforementioned stretching modes.
Molecular design of near-infrared fluorescent Pdots for tumor targeting: aggregation-induced emission versus anti-aggregation-caused quenching
(2019-01-07)
Tsai, Wei-Kai
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Wang, Chun-I.
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Liao, Chia-Hsien
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Yao, Chun-Nien
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Kuo, Tsai-Jhen
Semiconducting polymer dots (Pdots) have recently emerged as a new type of ultrabright fluorescent probe that has been proved to be very useful for biomedical imaging. However, Pdots often suffer from serious fluorescence aggregation-caused quenching (ACQ) especially for near-infrared (NIR) fluorescent Pdots. This article compared two strategies to overcome the ACQ effect in near-infrared emissive Pdot systems: aggregation-induced emission (AIE) and anti-aggregation-caused quenching (anti-ACQ). The results show that the anti-ACQ platform outperforms the AIE system. The fluorescence quantum yield of anti-ACQ-based Pdots can be over 50% and the average per-particle brightness of the Pdots is about 5 times higher than that of the commercially available quantum dots. To help understand why the monomer conformations could greatly affect the optical properties of Pdots, molecular dynamics simulations were performed for the first time in such complicated Pdot systems. To demonstrate applications for in vivo fluorescence imaging, both microangiography imaging on living zebrafish embryos and specific tumor targeting on mice were performed. We anticipate that these studies will pave the way for the design of new highly fluorescent Pdot systems.
Stereoselective synthesis of a 9-O-sulfo Neu5Gc-capped O-linked oligosaccharide found on the sea urchin egg receptor
(2019-01-07)
Das, Anindya
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Li, Pei-Jhen
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Adak, Avijit K.
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Wu, Hsin-Ru
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Anwar, Mohammad Tarique
A straightforward synthesis of the (25)-linked 9-O-sulfated Neu5Gc-capped O-linked tetrasaccharide (1) identified in the egg cell surface glycoproteins of the sea urchin Strongylocentrotus purpuratus receptor for sperm is reported. The construction of the (25)Neu5Gc trimer by the formation of an amide linkage rather than a glycosidic bond avoids the requirement for -stereoselective glycosylation. To highlight this amide bond formation strategy as a relatively facile method for synthesizing oligo-Neu5Gc containing O-linked glycans, its versatility is demonstrated by application to the coupling of SO3H-9Neu5Gc(25)Neu5Gc glycolic acid and a sialyl-Tn-derived amine for achieving the target tetrasaccharide. This synthetic strategy may be implemented in the generation of other structurally similar O-sulfo Neu5Gc-capped 25-O-glycolyl-linked oligo-Neu5Gc chains, enabling additional biological and chemical investigations.
交大e-News第270期-國際無人駕駛船挑戰賽交通大學首度出賽獲佳績
(2019-01-07)
國立交通大學秘書室
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Secretariat
Liver X Receptor/Retinoid X Receptor Pathway Plays a Regulatory Role in Pacing-Induced Cardiomyopathy
(2019-01-08)
Lin, Yu-Sheng
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Chang, Tzu-Hao
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Shi, Chung-Sheng
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Wang, Yi-Zhen
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Ho, Wan-Chun
Background-The molecular mechanisms through which high-demand pacing induce myocardial dysfunction remain unclear. Methods and Results-We created atrioventricular block in pigs using dependent right ventricular septal pacing for 6 months. Echocardiography was performed to evaluate dyssynchrony between pacing (n=6) and sham control (n=6) groups. Microarray and enrichment analyses were used to identify differentially expressed genes (DEGs) in the left ventricular (LV) myocardium between pacing and sham control groups. Histopathological and protein changes were also analyzed and an A cell pacing model was also performed. Pacing significantly increased mechanical dyssynchrony. Enrichment analysis using Ingenuity Pathway Analysis and the activation z-score analysis method demonstrated that there were 5 DEGs (ABCA1, APOD, CLU, LY96, and SERPINF1) in the LV septum (z-score=- 0.447) and 5 DEGs (APOD, CLU, LY96, MSR1, and SERPINF1) in the LV free wall (z-score=- 1.000) inhibited the liver X receptor/retinoid X receptor (LXR/RXR) pathway, and 4 DEGs (ACTA2, MYL1, PPP2R3A, and SNAI2) activated the integrin-linked kinase (ILK) pathway in the LV septum (z-score=1.000). The pacing group had a larger cell size, higher degree of myolysis and fibrosis, and increased expression of intracellular lipid, inflammatory cytokines, and apoptotic markers than the sham control group. The causal relationships between pacing and DEGs related to LXR/RXR and ILK pathways, apoptosis, fibrosis, and lipid expression after pacing were confirmed in the cell pacing model. Luciferase reporter assay in the cell pacing model also supported inhibition of the LXR pathway by pacing. Conclusions-Right ventricular septal-dependent pacing was associated with persistent LV dyssynchrony-induced cardiomyopathy through inhibition of the LXR/RXR pathway.
教育從小地方做起筆耕小書店
(國立交通大學傳播與科技學系, 2019-01-08)
蔡翔宇
筆耕小書店的成立與創辦人蔡文力現在的工作有關，他本身是友善書業合作社的成員，而筆耕小書店目前為友善書業合作社底下的獨立書店之一。筆耕小書店的二樓為筆耕寫作坊，主要提供給附近中小學生寫作課程，由蔡文力的太太擔任指導老師。
Energy Band Gap Modulation in Nd-Doped BiFeO3/SrRuO3 Heteroepitaxy for Visible Light Photoelectrochemical Activity
(2019-01-09)
Tan, Kok Hong
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Chen, Yun-Wen
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Chien Nguyen Van
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Wang, Hongliang
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Chen, Jhih-Wei
The ability of band offsets at multiferroic/metal and multiferroic/electrolyte interfaces in controlling charge transfer and thus altering the photoactivity performance has sparked significant attention in solar energy conversion applications. Here, we demonstrate that the band offsets of the two interfaces play the key role in determining charge transport direction in a downward self-polarized BFO film. Electrons tend to move to BFO/electrolyte interface for water reduction. Our experimental and first-principle calculations reveal that the presence of neodymium (Nd) dopants in BFO enhances the photoelectrochemical performance by reduction of the local electron hole pair recombination sites and modulation of the band gap to improve the visible light absorption. This opens a promising route to the heterostructure design by modulating the band gap to promote efficient charge transfer.
Porphyrin-Containing Polymer as a Superior Blue Light-Absorbing Additive To Afford High-J(sc) Ternary Solar Cells
(2019-01-09)
Li, Chia-Hua
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Chang, Chia-Chih
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Hsiao, Yu-Hsuan
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Peng, Shih-Hao
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Su, Yi-Jia
Integrating an additional component featuring complementary light absorption into binary polymer solar cells is a superior tactic to ameliorate solar cell efficiency and stability. An appropriate additive not only extends the absorption range but may also facilitate charge separation and transport processes. In this work, we elucidate the effects of incorporating a porphyrin-containing conjugated polymer (PPor-1), which displays absorption in 350-500 nm, into binary PTB7-Th:4TIC and PTB7-Th:ITIC blends, affording devices with an average power conversion efficiency approaching 9%. We successfully demonstrate that PPor-1 can be incorporated as an additive to impart improved J(sc) (up to 19.1 mA cm(-2)).
SDN-based dynamic multipath forwarding for inter-data center networking
(2019-01-10)
Wang, Yao-Chun
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Lin, Ying-Dar
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Chang, Guey-Yun
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資訊工程學系
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Department of Computer Science
Equal-cost multipath (ECMP)-based traffic engineering (TE) methods are commonly used in intra-data center (DC) networks to improve the transmission performance for east-west traffic (ie, traffic from server to server within a DC). However, applying ECMP on inter-DC wide area network (WAN) offers limited performance enhancement as a result of irregular network topology. Since TE can be intelligently and efficiently realized with software-defined networking (SDN), SDN-based multipath becomes a popular option. However, SDN suffers from scalability issue caused by limited ternary content-addressable memory (TCAM) size. In this paper, we propose an SDN-based TE method called dynamic flow-entry-saving multipath (DFSM) for inter-DC traffic forwarding. DFSM adopts source-destination-based multipath forwarding and latency-aware traffic splitting to reduce the consumption of flow entries and achieve load balancing. The evaluation results indicate that DFSM saves 15% to 30% of system flow entries in practical topologies and reduces the standard deviation of path latencies from 10% to 7% than do label-switched tunneling, and also reduces average latency by 10% to 48% by consuming 6% to 20% more flow entries than do ECMP in less-interconnected topologies. Note that the performance gain may not always be proportional to flow entry investment, with the interconnectivity between nodes being an important factor. The evaluation also indicates that per-flow provision consumes several times the flow entries consumed by DFSM but reduces latency by 10% at most. Besides, DFSM reduces the standard deviation of path latencies from 14% to 7% than do even traffic splitting.
A light-weight bit commitment protocol based on unpredictable channel noise
(2019-01-10)
Guan, Albert
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Tzeng, Wen-Guey
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資訊工程學系
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Department of Computer Science
Bit commitment is an important tool in the design of many secure cryptographic protocols, such as coin flipping, zero-knowledge proof, and secure computation. In this paper, we present a computationally light-weight bit commitment protocol over a noisy channel. For the security of the proposed protocol, we show that the receiver has almost no information about the committer's secret due to unpredictability of the noises in the communication channel. Hence, the security of our bit commitment protocol does not depend on hard problems; it is information-theoretically secure. Furthermore, the protocol needs only exclusive-or operations. Thus, it is computationally light-weight, and it can be used in the devices whose computing resources are limited. (C) 2018 Elsevier B.V. All rights reserved.
The evaluation of a better intubation strategy when only the epiglottis is visible: a randomized, cross-over mannequin study
(2019-01-10)
Hung, Tzu-Yao
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Lin, Li-Wei
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Yeh, Yu-Hang
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Su, Yung-Cheng
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Lin, Chieh-Hung
BackgroundThe Cormack-Lehane (C-L) grade III airway is considered to be a challenging airway to intubate and is associated with a poor intubation success rate. The purpose of this study was to investigate whether the holding position, shapes, bend angles of the endotracheal tube (ET) and the stylet-assisted lifting of the epiglottis could improve the success rate of intubation.MethodsThirty-two participants, 26 physicians, 2 residents, and 4 nurse practitioners, with 12.095.38years of work experience in the emergency department and more than 150 annual intubation events, were enrolled in this randomized, cross-over mannequin study. We investigated the effects of straight-to-cuff ET shapes with 35 degrees and 50 degrees bend angles, banana-shaped ET with longitudinal distances of 28cm and 26cm, two methods of holding the ET (either on the top or in the middle), and lifting or not the epiglottis, on the intubation duration, its success rate, and its subjective difficulty. The aim of the study is to provide optimized intubation strategies for difficult airway with C-L IIb or III grades, when the inlet of the trachea cannot be visualized.ResultsThe two groups that lifted the epiglottis using the stylets, in bend angles of 35 degrees and 50 degrees, had the shortest duration of intubation (23.7514.24s and 20.72 +/- 6.90s, hazard ratios 1.54 and 1.85 with 95% confidence intervals [95% CI] of 1.01-2.34 and 1.23-2.78, respectively) and a 100% success rate in intubations. In the survival analysis, lifting of the epiglottis was the only significant factor (p<0.0001, 95% CI 1.34-2.11) associated with the success rate of intubation.ConclusionsThe use of the epiglottic lift as an adjunctive technique can facilitate the intubation and improve its success rate without increasing procedure difficulty, in C-L III airway, when only the epiglottis is seen.Trial registration ClinicalTrials Registry (https://clincaltrials.gov, identifier NCT03366311).
Mimicking surface polaritons for unpolarized light with high-permittivity materials
(2019-01-10)
Papadakis, Georgia T.
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Davoyan, Artur
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Yeh, Pochi
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Atwater, Harry A.
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光電工程學系
Tailoring near-field optical phenomena often requires excitation of surface plasmon polaritons (SPPs) or surface phonon polaritons (SPhPs), surface waves at the interface between media with electric permittivities of opposite sign. Despite their unprecedented field confinement, surface polaritons are limited by polarization: only transverse magnetic fields enable their excitation, leaving transverse electric fields unexploited. By contrast, guided modes in positive permittivity materials occur for both linear polarizations, however, they typically cannot compete with SPPs and SPhPs in terms of confinement. Here we show that omnipolarization guided modes in materials with high-permittivity resonances can reach confinement factors similar to SPPs and SPhPs, while surpassing them in terms of propagation distance. We explore the cases of silicon carbide and transition-metal dichalcogenides near their permittivity resonances, and compare with SPhPs in silicon carbide and SPPs in silver, at infrared and visible frequencies, respectively.