Browsing by Issue Date, starting with "2017-11-27"

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Liquid-crystal tunable color filters based on aluminum metasurfaces
(2017-11-27)
Xie, Zu-Wen
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Yang, Jhen-Hong
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Vashistha, Vishal
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Lee, Wei
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Chen, Kuo-Ping
Designing color pixels using plasmonic nanostructures and metasurfaces has become a luring area of research in recent years. Here, we experimentally demonstrated the voltage tunability of a dynamic plasmonic color filter by using an aluminum grating integrated with the nematic liquid crystal (LC). Along with a typical substrate coated with rubbed polyimide film, the aluminum grating itself serves as a molecular alignment layer to form a twisted LC cell. This hybrid structure allows electrically controlled transmission color by applying the voltage. A significant spectral tunability of such a device has been demonstrated by applying the small voltage from 0 to 4 V-rms. (C) 2017 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Bistable transport properties of a quasi-one-dimensional Wigner solid on liquid helium under continuous driving
(2017-11-27)
Rees, David G.
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Yeh, Sheng-Shiuan
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Lee, Ban-Chen
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Kono, Kimitoshi
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Lin, Juhn-Jong
We investigate low-frequency fluctuations in the transport characteristics of a quasi-1D Wigner solid (WS) moving along a liquid helium substrate in response to a sinusoidal driving voltage. The fluctuations occur between distinct transport modes in which the decoupling of the WS from ripplonic polarons (or "dimple lattice," DL) formed on the helium surface does, or does not, occur during each ac cycle. We demonstrate that a Gaussian-like distribution in the decoupling threshold force gives rise to this bistability, as the low-frequency switching occurs when the probability of decoupling during each ac cycle is small but finite. We attribute the distribution in the decoupling threshold force to the range of structural configurations allowed for the quasi-1D electron lattice, which influences the strength of the WS-DL coupling. Hence, the switching rate between the ac transport modes is extremely sensitive to the microscopic properties of the electron solid.
Reversible Cleavage/Formation of the Chromium-Chromium Quintuple Bond in the Highly Regioselective Alkyne Cyclotrimerization
(2017-11-27)
Huang, Yu-Siang
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Huang, Gou-Tao
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Liu, Yao-Lun
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Yu, Jen-Shiang K.
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Tsai, Yi-Chou
Herein we report the employment of the quintuply bonded dichromium amidinates [Cr{(2)-HC(N-2,6-(Pr2C6H3)-Pr-i)(N-2,6-R2C6H3)}](2) (R=iPr (1), Me (7)) as catalysts to mediate the [2+2+2] cyclotrimerization of terminal alkynes giving 1,3,5-trisubstituted benzenes. During the catalysis, the ultrashort Cr-Cr quintuple bond underwent reversible cleavage/formation, corroborated by the characterization of two inverted arene sandwich dichromium complexes (-(6):(6)-1,3,5-(Me3Si)(3)C6H3)[Cr{(2)-HC(N-2,6-(Pr2C6H3)-Pr-i)(N-2,6-R2C6H3)}](2) (R=Pr-i (5), Me (8)). In the presence of sigma donors, such as THF and 2,4,6-Me3C6H2CN, the bridging arene 1,3,5-(Me3Si)(3)C6H3 in 5 and 8 was extruded and 1 and 7 were regenerated. Theoretical calculations were employed to disclose the reaction pathways of these highly regioselective [2+2+2] cylcotrimerization reactions of terminal alkynes.
From Electrospun Polymer Core-Shell Fibers to Polymer Hemispheres and Spheres: Two Types of Transformation Processes and Tearing Films with Linearly Arranged Cavities
(2017-11-28)
Chiu, Yu-Jing
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Tseng, Hsiao-Fan
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Lo, Yu-Ching
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Wu, Bo-Hao
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Chen, Jiun-Tai
Electrospun polymer core shell fibers have gained much attention because of their promising applications in areas such as electronic devices, drug delivery, and tissue engineering. The morphology transformation of polymer core shell fibers, however, has been rarely investigated. Here, we study the effect of thermal annealing on the morphology transformation of electrospun polystyrene (PS)/poly(methyl methacrylate) (PMMA) core-shell fibers on PMMA. films. Two types of transformation processes are discovered. In the first type of the transformation process (type I), the PS cores transform to hemispherical particles after the annealing process; in the second type of the transformation process (type II), the PS cores transform to spherical particles after the annealing process. The measured sizes of the hemispherical and spherical PS domains fall into two classified regions, as predicted for the two different types of transformation processes. It is also observed that the growth rates of the undulated amplitude are similar for the two different types of transformation processes, but the type I fibers start to undulate at later annealing times than the type II fibers do. When the PS particles are selectively removed, the PMMA films with linearly arranged cavities are used for the tearing experiments, demonstrating a proof of concept on the potentials in studying the mechanical properties of cavity-containing films.
Bacterial alterations in salivary microbiota and their association in oral cancer
(2017-11-28)
Lee, Wei-Hsiang
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Chen, Hui-Mei
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Yang, Shun-Fa
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Liang, Chao
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Peng, Chih-Yu
Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity and the fourth leading malignancy and cause of cancer-related death in the male population of Taiwan. Most cases are detected at advanced stages, resulting in poor prognosis. Therefore, improved detection of early oral health disorders is indispensable. The involvement of oral bacteria in inflammation and their association with OSCC progression provide a feasible target for diagnosis. Due to the nature of oral neoplasms, the diagnosis of epithelial precursor lesions is relatively easy compared with that of other types of cancer. However, the transition from an epithelial precursor lesion to cancer is slow and requires further and continuous follow-up. In this study, we investigated microbiota differences between normal individuals, epithelial precursor lesion patients, and cancer patients with different lifestyle habits, such as betel chewing and smoking, using next-generation sequencing. Overall, the oral microbiome compositions of five genera, Bacillus, Enterococcus, Parvimonas, Peptostreptococcus, and Slackia, revealed significant differences between epithelial precursor lesion and cancer patients and correlated with their classification into two clusters. These composition changes might have the potential to constitute a biomarker to help in monitoring the oral carcinogenesis transition from epithelial precursor lesion to cancer.
Health disparities are associated with gastric cancer mortality-to-incidence ratios in 57 countries
(2017-11-28)
Tsai, Ming-Chang
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Wang, Chi-Chih
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Lee, Hsiang-Lin
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Peng, Cheng-Ming
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Yang, Tzu-Wei
AIM To evaluate the association between mortality-to- incidence ratios (MIRs) and health disparities. METHODS In this study, we used the GLOBOCAN 2012 database to obtain the cancer incidence and mortality data for 57 countries, and combined this information with the World Health Organization (WHO) rankings and total expenditures on health/gross domestic product (e/GDP). The associations between variables and MIRs were analyzed by linear regression analyses and the 57 countries were selected according to their data quality. RESULTS The more developed regions showed high gastric cancer incidence and mortality crude rates, but lower MIR values than the less developed regions (0.64 vs 0.80, respectively). Among six continents, Oceania had the lowest (0.60) and Africa had the highest (0.91) MIR. A good WHO ranking and a high e/GDP were significantly associated with low MIRs (p = 0.001 and p = 0.001, respectively). CONCLUSION The MIR variation for gastric cancer would predict regional health disparities.
Preventing market collapse in auctions for perishable Internet of Things resources
(2017-11-29)
Safianowska, Maria B.
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Gdowski, Robert
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Huang, ChingYao
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
We are entering the era of digital business moments where autonomous things will buy and sell services from each other in order to make people's life easier. They will also negotiate in order to achieve the best price for their services which will result in Internet of Things auctions. Such auctions will be combinatorial and recurrent. Recurrent auctions pose a problem of bidder drop which leads to market collapse. Moreover, in Internet of Things, bidders will employ different strategies according to their pattern of consuming resources. We describe two bidding strategies which may lead to market collapse or very low revenue: opportunistic and periodic bidding. We devise two algorithms: revenue maximizing auction and highest bid lock auction, analyze their performance under these two bidding strategies, and compare them to traditional combinatorial auction. We find out that the revenue maximizing auction prevents market collapse under opportunistic bidding while highest bid lock auction provides the highest revenue under both strategies.
OPTICAL DETECTING DEVICE
(2017-11-29)
OU-YANG, Mang
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HUANG, Ting-Wei
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CHIANG, Hou-Chi
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HE, Zheng-Lin
An optical detecting device includes a reflecting element, a main body, a light source and a plurality of photosensitive elements. The reflecting element has a reflecting surface. The main body has an installing surface. The installing surface at least partially faces to the reflecting surface. The main body is configured to move along a moving direction relative to the reflecting element. The moving direction is substantially parallel with the reflecting surface. The light source is disposed on the installing surface and is configured to emit a light ray towards the reflecting surface. The photosensitive elements are disposed on the installing surface. Sides of the photosensitive elements close to the light source surround to form a light source region. The light source is at least partially located in the light source region.
MOTION DETECTING DEVICE, MOTION DETECTING SENSOR UNIT AND MOTION DETECTION METHOD
(2017-11-30)
Kelvin Yi-Tse LAI
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Yu-Lin TSAI
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Chen-Yi LEE
A motion detecting device includes an accelerometer configured to generate gravitational acceleration readings associated respectively with consecutive time segments, an angular acceleration sensor and configured to generate angular acceleration readings, and a processor operable in one of a standby mode and an active mode. When operated in the standby mode, the processor activates the accelerometer, deactivates the angular acceleration sensor, and determines whether the user is in a substantial moving state. When determined that the user is in the substantial moving state, the processor switches to the active mode to activate both the accelerometer and said angular acceleration sensor, in order to determine the motion of the user.
ANTIBODY
(2017-11-30)
Yaw-Kuen LI
;
Mo-Yuan SHEN
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Hsiu-Pen LIN
An antibody includes a polyamidoamine (PAMAM) dendrimer and a first functional group. The polyamidoamine (PAMAM) dendrimer includes a plurality of branches and each of the branches has a phenylboronic acid (PBA) terminal group. The first functional group is bonded to at least one of the PBA terminal groups.
「賣某少頭嘴」：從「以妻為貨」現象窺探臺灣底層社會的能動性（從清領到日治初期）
(國立陽明交通大學出版社, 2017-12-01)
張孟珠
本文探究清領到日治初期，臺灣中、下社會存在的「以妻為貨」現象。當丈夫貧極、病篤，無力治生養家時，唯有出此下策、典賣他所僅剩的資產－他的結髮妻子；或有生性浮浪、蕩盡家財，而以嫁賣、縱姦為續命之所憑。在生產方式保持穩定的時代，婚姻相對是傳統社會結構的原動力。作者利用清代刑科檔案、契約文書、日治報章時文、風俗調查報告、法院判決書等等，呈顯漢人婚姻、家庭體系中的女性交換，不乏在習俗實踐的表象下，挾帶走私了或暫或久、或隱或顯的賣春成分；同時揭露近代早期，潛藏於販夫走卒心態上的婚姻譜系與位階關係，他們的能動性格、及其對菁英價值的創造性轉化。
Solvent-assisted crystallization via a delayed-annealing approach for highly efficient hybrid mesoscopic/planar perovskite solar cells
(2017-12-01)
Sutanto, Albertus Adrian
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Lan, Shiang
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Cheng, Chih-Fu
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Mane, Sandeep B.
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Wu, Hui-Ping
The formation of a dense and uniform perovskite film with large grain is an important factor for getting excellent device performance. Here, we report an optimized solvent-assisted crystallization procedure followed by a delayed annealing for easy and reproducible fabrications of perovskite solar cells with a hybrid mesoscopic configuration. The working electrode contains a mesoporous TiO2 scaffold layer of 100 nm deposited on FTO substrate with a thin TiO2 blocking layer. The devices in this study were assembled using all commercially available materials without any extensive modification. Formation of uniform and pin-hole free perovskite nanocrystals with film thickness 200 nm on top of the scaffold layer was achieved via an optimized solvent assisted crystallization method. A much smoother perovskite layer was achieved with a delayed annealing for a certain period. The best performing device was obtained at the annealing delayed for 60 min, giving the power conversion efficiency 16.9% with an average value 15.4% obtained from 60 devices.
Generating high-peak-power structured lights in selectively pumped passively Q-switched lasers with astigmatic mode transformations
(2017-12-01)
Chang, C. C.
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Hsieh, Y. H.
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Lee, C. Y.
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Sung, C. L.
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Tuan, P. H.
Various high-order Hermite-Gaussian (HG) modes with high repetition rates and high peak powers are systematically generated by designing the cavity configuration to satisfy the criterion of the passive Q-switching. For the HG(m,0) modes with the order m = 1-9, the pulse repetition rate can exceed 100 kHz with peak power higher than 0.3 kW. For the HG(m,m) modes with the order m = 1-10, the pulse repetition rate can be up to 37 kHz with peak power higher than 0.35 kW. Furthermore, the high-order HG beams is transformed by using an astigmatic mode converter to generate various structured lights with optical vortices. Experimental patterns of the transformed high-order HG beams in the propagation are theoretically analyzed and the phase structures are numerically manifested.
Resistive random access memory (RRAM) technology: From material, device, selector, 3D integration to bottom-up fabrication
(2017-12-01)
Chen, Hong-Yu
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Brivio, Stefano
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Chang, Che-Chia
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Frascaroli, Jacopo
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Hou, Tuo-Hung
Emerging non-volatile memory technologies are promising due to their anticipated capacity benefits, non-volatility, and zero idle energy. One of the most promising candidates is resistive random access memory (RRAM) based on resistive switching (RS). This paper reviews the development of RS device technology including the fundamental physics, material engineering, three-dimension (3D) integration, and bottom-up fabrication. The device operation, physical mechanisms for resistive switching, reliability metrics, and memory cell selector candidates are summarized from the recent advancement in both industry and academia. Options for 3D memory array architectures are presented for the mass storage application. Finally, the potential application of bottom-up fabrication approaches for effective manufacturing is introduced.
Improving color saturation of blue light-emitting electrochemical cells by plasmonic filters
(2017-12-01)
Chiang, Chien-Ming Fan
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Chang, Bo-Ren
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Lee, Ya-Ju
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Sarma, Monima
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Yang, Zu-Po
In consideration of the advantages of light-emitting electrochemical cells (LECs), it is desired to develop the saturated blue LECs for LEC display, which is hindered by the features of broad emission spectrum and emission peak not short enough. In this study, we demonstrated a novel method to improve blue saturation of the sky-blue LECs by engineering its emission spectrum through the plasmonic filters. These plasmonic filters composed of randomly distributed silver nanoparticles (Ag-NPs) can absorb the green and red emission tail of the sky-blue LECs due to localized surface plasmon resonance (LSPR). The LSPR wavelengths of Ag-NPs are tuned by manipulating the effective refractive index of materials around Ag-NPs through the accurate control of the TiO2 thickness using atomic layer deposition technique. By integrating with the plasmonic filters, the CIE1931 coordinate of the blue LECs can approach to (0.14, 0.22), which is comparable to or even better than the reported bluest values of blue LECs. Combination with the green and red LECs, the color gamut increases from 34% (without filters) to 54% of National Television System Committee (NTSC) color gamut, corresponding to 1.6 times enhancement. In addition, the blue LECs integrated with plasmonic filters still have better efficiency than those of the reported bluest LECs. (C) 2017 Elsevier B.V. All rights reserved.
Heat transfer measurement in a rotating cooling channel with staggered and inline pin-fin arrays using liquid crystal and stroboscopy
(2017-12-01)
Huang, Szu-Chi
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Wang, Chen-Chih
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Endwall heat transfer in the stationary and rotating cooling channels with pin-fin arrays (inline and staggered pattern) were experimentally measured by wide band liquid crystal. The temperature measurement was performed with the stroboscopic photography to capture the reflected color from the liquid crystal coatings on the rotating object. A detailed calibration was performed to quantify the uncertainties in the liquid crystal measurement from the stroboscope frequency, flash duration, and viewing angle. The Reynolds numbers ranged from 5000 to 20000 and the rotation numbers ranged from 0 to 0.52. This measurement technique provided detailed heat transfer variations caused by the distinct secondary flow patterns from pin-fin and rotation. Results showed that the heat transfer from the staggered array was 25-30% higher than the inline array in the stationery channel. The rotation led to unsymmetrical heat transfer distributions along the spanwise direction. The heat transfer variation caused by rotation was more noticeable for the inline array, and the heat transfer in the rotating channel was more than 50% than that in the stationary channel. (C) 2017 Elsevier Ltd. All rights reserved.
Nanomechanical properties of Ag solder bumps doped with Pd and Au
(2017-12-01)
Wen, Hua-Chiang
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Chou, Wu-Ching
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Lin, Shiuan Huei
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Jiang, Don Son
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電子物理學系
As an approach to increasing their reliability, we doped Ag solder bumps with Pd and Au alloys to enhance their creep resistance, which we characterized using a nanoindentation technique. The hardnesses of the pure Ag and the Ag solders doped with Pd:3%, Pd:5%, and Pd:2%-Au:3% were 0.6 +/- 0.1, 1.8 +/- 02, 2.8 +/- 03, and 3.1 +/- 0.5 GPa, respectively. Although the hardness of the Ag solder was enhanced significantly when it contained Pd:2%-Au:3%, it exhibited a lower creep exponent (n > 2). The mechanism of the thermal recovery of the sample appears to be associated with activation of dislocation sources-also the reason for the decrease in hardness. The compounds doped with Pd:2%-Au:3% displayed significantly greater bond strengths and creep exponents, whereas the Pd only compounds exhibited poorer reliability. (C) 2017 Elsevier Ltd. All rights reserved.
中國特色毒性陽剛氣
(國立陽明交通大學出版社, 2017-12-01)
向在榮
A direct conversion transmitter with digital-assisted DC offset and I/Q phase calibration
(2017-12-01)
Chang, Chia-Hung
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Chen, Wei-Hsien
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Gong, Cihun-Siyong Alex
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Hu, Wei-Wen
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電機工程學系
A direct conversion transmitter with auto-calibration mechanism is presented in this paper. Both the carrier leakage and in-phase/quadrature (I/Q) phase imbalance are compensated by a proposed calibration algorithm to improve transmitter's single-sideband performance. The digital-assisted correction circuits are implemented in a calibration feedback path to reduce the mismatches and variations, which in turn achieves properties of high linearity, high sideband, and carrier suppression ratio. The measured single-sideband performance with calibration applied to the transmitter demonstrates an over 40 and 50-dBc rejection on sideband and carrier signals at the desired frequency band, respectively. For linearity performance, the measured output 1-dB compression point (OP1dB) is 9.1dBm, while the highest voltage gain is from 4.3 to 6.2dB. Additionally, the error vector magnitude (EVM) of -37.082dB (< 1.4%) can be achieved under an orthogonal frequency division multiple access (OFDMA) 64 QAM-3/4 modulated signal test. The transmitter consumes 112.7mA under supply voltage of 3.3V using the TSMC SiGe BiCMOS technology. Copyright (c) 2017 John Wiley & Sons, Ltd.
Enhancing extracted electroluminescence from light-emitting electrochemical cells by employing high-refractive-index substrates
(2017-12-01)
Jang, Yea-Fen
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Lin, Tzu-Chun
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Guo, Jhih-Yan
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Chiang, Chien-Ming Fan
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Wu, Ming-Lun
Solidstate lightemitting electrochemical cells (LECs) show several advantages over conventional organic lightemitting devices (OLEDs) such as simple device structure compatible with solution processes, low operation voltage and capability of utilizing inert cathode metals. However, device performance of LECs must be improved, e.g. enhancing light extraction, to meet the requirements for practical applications. Among the optical modes trapped in LECs, light trapped in substrate mode is easier to be extracted, e.g., by simply roughing the output surface. Therefore, increasing the percentage of substrate mode is beneficial in improving light extraction. In this work, the contributions of optical modes in LECs employing substrates with various refractive indices are analyzed. Higherrefractiveindex substrates are shown to trap more light in the substrates. Smaller refractive index difference between higher-refractive-index substrate and indium tin oxide (ITO) layer also increases the cutoff spectral range of light waveguided in ITO layer. Furthermore, light intensity in surface plasmon mode significantly reduces as the refractive index of the substrate increases. Reducing the percentage of surface plasmon mode facilitates light extraction since it requires more complicated methods for outcoupling light in this mode. With commercially available unpolished sapphire substrates, light output of LECs is enhanced by 56%. When a scattering layer was inserted between ITO and sapphire substrate, more light in substrate mode can be extracted and 71% enhancement in light output is realized. High external quantum efficiency up to 5.5% is consequently obtained in LECs based on a ruthenium complex. Such device efficiency is among the highest reported values for redemitting LECs and thus confirms that utilizing higher-refractive-index substrates would offer a simple and feasible approach to improve light output of LECs. In comparison to OLEDs, increased EL trapped in substrates of LECs mainly comes from surface plasmon mode rather than waveguide mode. (C) 2017 Elsevier B.V. All rights reserved.