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

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具寬能隙氧化物之深紫外線感測裝置
(2019-04-01)
洪瑞華
;
李彥助
;
董俊沂
;
蔡錫翰
;
鄭力中
本發明為一種具寬能隙氧化物之深紫外線感測裝置，其利用一氧化物磊晶感測層設置於基板，使深紫外線(Deep Ultraviolet)感測裝置具較佳之特性，，且進一步使深紫外線刺激氧化物磊晶感測層之光電流大幅增加，特別是針對深紫外光波段(280-200 nm)之感測效能大為提升。
EpiRank: Modeling Bidirectional Disease Spread in Asymmetric Commuting Networks
(2019-04-01)
Huang, Chung-Yuan
;
Chin, Wei-Chien-Benny
;
Wen, Tzai-Hung
;
Fu, Yu-Hsiang
;
Tsai, Yu-Shivan
Commuting network flows are generally asymmetrical, with commuting behaviors bi-directionally balanced between home and work locations, and with weekday commutes providing many opportunities for the spread of infectious diseases via direct and indirect physical contact. The authors use a Markov chain model and PageRank-like algorithm to construct a novel algorithm called EpiRank to measure infection risk in a spatially confined commuting network on Taiwan island. Data from the country's 2000 census were used to map epidemic risk distribution as a commuting network function. A daytime parameter was used to integrate forward and backward movement in order to analyze daily commuting patterns. EpiRank algorithm results were tested by comparing calculations with actual disease distributions for the 2009 H1N1 influenza outbreak and enterovirus cases between 2000 and 2008. Results suggest that the bidirectional movement model outperformed models that considered forward or backward direction only in terms of capturing spatial epidemic risk distribution. EpiRank also outperformed models based on network indexes such as PageRank and HITS. According to a sensitivity analysis of the daytime parameter, the backward movement effect is more important than the forward movement effect for understanding a commuting network's disease diffusion structure. Our evidence supports the use of EpiRank as an alternative network measure for analyzing disease diffusion in a commuting network.
108年8月10-11日陽明大學牙醫校友總會校友聯誼活動
(國立陽明大學牙醫校友會, 2019-04)
温斯勇
Enantioselective Synthesis of Hydantoin and Diketopiperazine-Fused Tetrahydroisoquinolines via Pictet-Spengler Reaction
(2019-04-01)
Liu, Shih-I
;
Haung, Jia-Yun
;
Barve, Indrajeet J.
;
Huang, Sheng-Cih
;
Sun, Chung-Ming
An enantioselective synthesis of iso-, isothio-, and isoselenohydantoin and diketopiperazine-fused tetrahydroisoquinolines from L-Dopa was reported. The route consists of an Pictet-Spengler reaction of (S)-2-amino-3-(3,4-dimethoxyphenyl)propanoates with various aldehydes to afford diastereomeric tetrahydroisoquinolines. Next step, the tetrahydroisoquinolines were further reacted with iso-, isothio-, or isoselenocyanates to construct hydantoin. Similarly, the diketopiperazine moiety was constructed by subjecting tetrahydroisoquinolines to a condensation reaction with chloroacetyl chloride followed by nucleophilic addition with various primary amines.
Classification and Evolution of Bifurcation Curves for a Dirichlet-Neumann Boundary Value Problem and its Application
(2019-04-01)
Kuo, Da-Chang
;
Wang, Shin-Hwa
;
Liang, Yu-Hao
;
應用數學系
;
Department of Applied Mathematics
We study the classification and evolution of bifurcation curves of positive solutions for the one-dimensional Dirichlet-Neumann boundary value problem {u ''(x) + lambda f (u) = 0, 0 < x < 1, u(0) = 0, u' (1) = -c < 0, where lambda > 0 is a bifurcation parameter and c > 0 is an evolution parameter. We mainly prove that, under some suitable assumptions on f, there exists c(1) > 0, such that, on the (lambda,parallel to u parallel to(infinity))-plane, (i) when 0 < c < c(1), the bifurcation curve is S-shaped; (ii) when c >= c(1), the bifurcation curve is subset of-shaped. Our results can be applied to the one-dimensional perturbed Gelfand equation with f(u) = exp (au/a+u) for a >= 4.37.
MAL-PDT inhibits oral precancerous cells and lesions via autophagic cell death
(2019-04-01)
Wang, Yen-Yun
;
Chen, Yuk-Kwan
;
Hu, Chu-Sung
;
Xiao, Ling-Yi
;
Huang, Wan-Ling
Background Oral cancer is a common cancer with a high mortality rate. While surgery is the most effective treatment for oral cancer, it frequently causes deformity and dysfunction in the orofacial region. In this study, methyl aminolevulinate photodynamic therapy (MAL-PDT) as a prevention tool against progression of precancerous lesion to oral cancer was explored. Methods For in vitro studies, we evaluated the effects of MAL-PDT on viability of DOK oral precancerous cells by XTT, cell morphology by TEM, and intracellular signaling pathways by flow cytometry, Western blotting, and immunofluorescence. For in vivo study, DMBA was used to induce oral precancerous lesions in hamsters followed by MAL-PDT treatment. We measured tumor size and body weight weekly. After sacrifice, buccal pouch lesions were processed for H&E stain and immunohistochemistry analysis. Results MAL-PDT induced autophagic cell death in DOK oral precancerous cells. The autophagy-related markers LC3II and p62/SQSTM1 and autophagosome formation in DOK cells were increased after MAL-PDT treatment. In vivo, MetvixA (R)-PDT treatment decreased tumor growth and enhanced LC3II expression in hamster buccal pouch tumors induced by DMBA. Conclusions Our in vitro and in vivo results suggest that MAL-PDT may provide an effective therapy for oral precancerous lesions through induction of autophagic cell death.
An Overflow Problem in Network Coding for Secure Cloud Storage
(2019-04-01)
Chen, Yu-Jia
;
Wang, Li-Chun
;
交大名義發表
;
電機工程學系
;
National Chiao Tung University
In this paper, we present the overflow problem of a network coding storage system (NCSS) when the encoding parameters and the storage parameters are mismatched. The overflow problem of the NCSS occurs because the network-coded encryption yields extended coded data, resulting in high storage and processing overhead. To avoid the overflow problem, we propose an overflow-avoidance NCSS scheme that takes account of security and storage requirements in both encoding and storage procedures. We provide the analytical results of the maximum allowable stored encoded data under the perfect secrecy criterion. The design guidelines to achieve high coding efficiency with the lowest storage cost are also presented.
國立陽明大學牙醫校友總會第十七屆理監事組織表
(國立陽明大學牙醫校友會, 2019-04)
LiSiOX-Based Analog Memristive Synapse for Neuromorphic Computing
(2019-04-01)
Chen, Jia
;
Lin, Chih-Yang
;
Li, Yi
;
Qin, Chao
;
Lu, Ke
The progress in the neuromorphic computing hinges on the development of nanoscale analog artificial synapses. Here, we report a LiSiOX (LSO)-based memristive synapse with 100-level conductance states under identical pulses, representing synaptic potentiation and depression behaviors. The superior analog behaviors originate from the dynamic evolution of an electro-thermal modulation region with the motion of lithium and oxygen ions. A three-layer perceptron was constructed in simulation with LSO synapses, and a 91.97% recognition accuracy was achieved for handwritten digits. Moreover, the influences of several critical parameters, including device variability and weight precision, on the accuracy have been investigated. This letter provides guidelines for the optimization of synaptic device in robust memristive neural network.
Ultra-High Light Extraction Efficiency and Ultra-Thin Mini-LED Solution by Freeform Surface Chip Scale Package Array
(2019-04-01)
Huang, Che-Hsuan
;
Kang, Chieh-Yu
;
Chang, Shu-Hsiu
;
Lin, Chih-Hao
;
Lin, Chun-Yu
In this study, we present a novel type of package, freeform-designed chip scale package (FDCSP), which has ultra-high light extraction efficiency and bat-wing light field. For the backlight application, mainstream solutions are chip-scale package (CSP) and surface-mount device package (SMD). Comparing with these two mainstream types of package, the light extraction efficiency of CSP, SMD, and FDCSP are 88%, 60%, and 96%, respectively. In addition to ultra-high light extraction efficiency, because of the 160-degree bat-wing light field, FDCSP could provide a thinner and low power consumption mini-LED solution with a smaller number of LEDs than CSP and SMD light source array.
Integrated Silicon Photonics Remote Radio Frontend (RRF) for Single-Sideband (SSB) Millimeter-Wave Radio-Over-Fiber (ROF) Systems
(2019-04-01)
Tong, Yeyu
;
Chow, Chi-Wai
;
Chen, Guan-Hong
;
Peng, Ching-Wei
;
Yeh, Chien-Hung
Radio-over-fiber (ROF)-based mobile fronthaul network supporting the baseband unit and simple remote radio head is a promising network architecture for future wireless networks. In this paper, we propose and demonstrate a silicon photonics (SiPh)-based remote radio frontend (RRF) for the mm-wave ROF systems. The proposed SiPh-based RRF consisted of an integrated Mach-Zehnder modulator and a micro-ring modulator, producing a single-sideband 40 GHz millimeter-wave orthogonal-frequency-division-multiplexing ROF signal, which is robust against fiber chromatic dispersion in the mobile fronthaul transmission. The RRF is fabricated using SiPh platform and could be potentially low cost. High split-ratios can be potentially achieved. Data rate of 7.813 Gbit/s per wavelength channel is achieved in the experiment. Numerical analysis is also performed; there are good matches of the simulation and experimental results.
Dielectric impact on exciton binding energy and quasiparticle bandgap in monolayer WS2 and WSe2
(2019-04-01)
Hsu, Wei-Ting
;
Quan, Jiamin
;
Wang, Chun-Yuan
;
Lu, Li-Syuan
;
Campbell, Marshall
Excitons, bound electron-hole pairs in a 2D plane, dominate the optical properties of monolayer transition metal dichalcogenides (TMDs). A large exciton binding energy on the order of 0.5 eV was theoretically predicted and experimentally determined recently. These ultrastable excitons thus open an avenue to explore the exciton physics such as Bose-Einstein condensation and superfluidity at room temperature (Kasprzak et al 2006 Nature 443 409; Plumhof et al 2014 Nat. Mater. 13 247; Fogler et al 2014 Nat. Commun. 5 4555; Jiang and John 2014 Sci. Rep. 4 7432). Recent experiments further demonstrated the concept of Coulomb engineering via dielectric environments based on either solutions or few-layer graphene. However, the conducting nature of these dielectrics can lead to quenching of optical transitions. Thus, in order to utilize 'dielectric tuning' of the exciton binding energy and quasiparticle band gaps, one must use insulating dielectrics. Here, we investigate the impact of insulating dielectric environments on the exciton binding energy of monolayer WS2 and WSe2 by exciton Rydberg spectroscopy, in which the dielectric environment is systematically varied from kappa= 1.49 to 3.82. We found that, with increasing kappa value, the exciton binding energy and quasiparticle bandgap exhibit significant reductions. Quantitatively, our result follows the prediction of nonlocally-screened Keldysh potential very well. The fitted 2D polarizability, Chi(2D), agrees rather well with previous density function theory calculations. Their close agreement validates the nonlocally-screened Keldysh model which can be used to quantitatively predict the exciton binding energy for monolayer TMDs (and possibly other 2D materials) in different dielectric environments. Such a predictive model will play an important role for the design of van der Waals heterostructures and TMD-based optoelectronic devices.
影像選輯
(深河出版有限公司, 2019-04-01)
寧舟浩
Monolayer MoS2 Enabled Single-Crystalline Growth of AlN on Si(100) Using Low-Temperature Helicon Sputtering
(2019-04-01)
Hsu, Wei-Fan
;
Lu, Li-Syuan
;
Kuo, Po-Chun
;
Chen, Jie-He
;
Chueh, Wei-Chen
Growing a single-crystalline film on a substrate relies on the compatibility of crystal symmetry and lattice constant between the two materials. Such limitations can be circumvented by introducing van der Waals epitaxy of three-dimensional (3D) crystals on two-dimensional (2D) layered materials. Recently, buffer-assisted growth of III-nitride films on graphene has been demonstrated. However, the low chemical reactivity of graphene surface considerably limits the large-area and single-crystalline growth of planar 3D films on 2D layered materials. Here, we demonstrate that using highly oriented monolayer MoS2 as a buffer layer, single-crystalline AlN thin films can be grown on Si(100) substrates, which possess a different crystal symmetry with the films. The AlN films were grown by helicon sputtering system at low temperature (400 degrees C), showing a very flat surface with a root-mean-square roughness of 1.0 nm and an X-ray rocking curve with a full width at half-maximum of 0.336 degrees, indicating a high-crystalline quality. Because the buffer layer as well as the AlN films were prepared at low temperatures, our results not only pave the way for integrating III-nitride with the Si wafer industry process but also open a new possibility for growing III-nitride thin film on various foreign substrates.
Phomaketide A Inhibits Lymphangiogenesis in Human Lymphatic Endothelial Cells
(2019-04-01)
Tai, Huai-Ching
;
Lee, Tzong-Huei
;
Tang, Chih-Hsin
;
Chen, Lei-Po
;
Chen, Wei-Cheng
Lymphangiogenesis is an important biological process associated with cancer metastasis. The development of new drugs that block lymphangiogenesis represents a promising therapeutic strategy. Marine fungus-derived compound phomaketide A, isolated from the fermented broth of Phoma sp. NTOU4195, has been reported to exhibit anti-angiogenic and anti-inflammatory effects. However, its anti-lymphangiogenic activity has not been clarified to date. In this study, we showed that phomaketide A inhibited cell growth, migration, and tube formation of lymphatic endothelial cells (LECs) without an evidence of cytotoxicity. Mechanistic investigations revealed that phomaketide A reduced LECs-induced lymphangiogenesis via vascular endothelial growth factor receptor-3 (VEGFR-3), protein kinase C (PKC), and endothelial nitric oxide synthase (eNOS) signalings. Furthermore, human proteome array analysis indicated that phomaketide A significantly enhanced the protein levels of various protease inhibitors, including cystatin A, serpin B6, tissue factor pathway inhibitor (TFPI), and tissue inhibitor matrix metalloproteinase 1 (TIMP-1). Importantly, phomaketide A impeded tumor growth and lymphangiogenesis by decreasing the expression of LYVE-1, a specific marker for lymphatic vessels, in tumor xenograft animal model. These results suggest that phomaketide A may impair lymphangiogenesis by suppressing VEGFR-3, PKC, and eNOS signaling cascades, while simultaneously activating protease inhibitors in human LECs. We document for the first time that phomaketide A inhibits lymphangiogenesis both in vitro and in vivo, which suggests that this natural product could potentially treat cancer metastasis.
揮桿吧！Let's Enjoy Golf~
(國立陽明大學牙醫校友會, 2019-04)
鄭銘鎮
Liquid-crystal-based magnetically tunable terahertz achromatic quarter-wave plate
(2019-04-01)
Hsieh, Cho-Fan
;
Yang, Chan-Shan
;
Shih, Fang-Cih
;
Pan, Ru-Pin
;
Pan, Ci-Ling
Development of the wideband and tunable quasi-optic terahertz (THz) components is in high demand. In this work, we demonstrate a tunable achromatic quarter-wave plate (AQWP) for the THz frequency range. The phase retardation of this device can be set at 90 degrees +/- 9 degrees from 0.20 to 0.50 THz. The operation range from 0.20 to 0.50 THz can be tuned to from 0.30 to 0.70 THz by introducing three nematic liquid crystals phase retarders, of which the birefringence can be magnetically tuned. The frequency-dependent phase retardation is in good agreement with theoretical predictions. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
資訊科技稽核品質、資訊科技內部控制與資訊科技治理之關聯性研究
(國立交通大學經營管理研究所, 2019-04-01)
吳東憲
;
黃劭彥
;
康照宗
;
Tung-Hsien Wu
;
Shaio Yan Huang
過去的研究透過不同層面探討影響資訊科技治理成效之因素，然而，資訊科技稽核品質與資訊科技內部控制對資訊科技治理之影響鮮少被提及。本研究首先探討資訊科技內部控制對資訊科技治理成效之影響。再者，本研究探討資訊科技稽核品質對資訊科技內部控制之影響。最後，探討資訊科技稽核品質對資訊科技治理成效之直接與間接影響。本研究透過問卷以偏最小平方迴歸進行分析，問卷發放對象為上市公司內部稽核人員。實證結果顯示資訊科技內部控制正向顯著影響資訊科技治理成效，資訊科技稽核品質正向顯著影響資訊科技內部控制。資訊科技稽核品質正向顯著影響資訊科技治理成效，並透過資訊科技內部控制間接顯著影響資訊科技治理成效。本研究提供學術與實務界改善內部稽核部門配置、資訊科技內部控制之建置以及資訊科技治理影響因素之參考。
全民健康保險醫療費用審查注意事項部份修正規定
(國立陽明大學牙醫校友會, 2019-04)
張宏羽
Privacy Protection for Internet of Drones: A Network Coding Approach
(2019-04-01)
Chen, Yu-Jia
;
Wang, Li-Chun
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper proposes an enhanced secure pseudonym scheme to protect the privacy of cloud data in Internet of Drones (IoD). Nowadays, drones equipped with cameras can provide surveillance and aerial photography applications. Unlike the video devices, personal drones with high mobility can track and follow an individual, causing both the identity and location privacy issues. However, IoD devices cannot implement complex cryptographic schemes because of limited computing power. To this end, we develop a secure light-weight network coding pseudonym scheme. Our designed two-tier network coding can decouple the stored IoD cloud data from the owner's pseudonyms. Therefore, our proposed network coding-based pseudonym scheme can simultaneously defend against both outside and inside attackers. We implement our proposed two-tier light-weight network coding mechanism when facing untrusted cloud database. Compared to the computationally secure hash-based pseudonym scheme, our proposed scheme achieves the highest unconditional security level, but also can reduce more than 90% of processing time as well as 10% of energy consumption.