Browsing by Issue Date, starting with "2015-01-06"

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Rumor source detection for rumor spreading on random increasing trees
(2015-01-06)
Fuchs, Michael
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Yu, Pei-Duo
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應用數學系
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Department of Applied Mathematics
In a recent paper, Shah and Zaman proposed the rumor center as an effective rumor source estimator for rumor spreading on random graphs. They proved for a very general random tree model that the detection probability remains positive as the number of nodes to which the rumor has spread tends to infinity. Moreover, they derived explicit asymptotic formulas for the detection probability of random d - regular trees and random geometric trees. In this paper, we derive asymptotic formulas for the detection probability of grown simple families of random increasing trees. These families of random trees contain important random tree models as special cases, e. g., binary search trees, recursive trees and plane- oriented recursive trees. Our results show that the detection probability varies from 0 to 1 across these families. Moreover, a brief discussion of the rumor center for unordered trees is given as well.
Method and system for detecting an applicance based on users' feedback information
(2015-01-06)
Tsao Shiao-Li
;
Lai Yi-Sheng
A method and system for detecting an appliance based on users' feedback information, particularly a nonintrusive load monitoring method and system based on a user's feedback information and a joint strategic decision search algorithm are disclosed. By means of obtaining the users' feedback information on an appliance inputted by users or a search result of the appliances being confirmed by the users to generate a mapping between the model of the appliances and at least one load signature of each model of appliances; the users' feedback information is recorded into a smart meter or a cloud computing system, and a mathematical analysis is further used to compute an occurrence of any one signature of the appliance and the identification rate of each signature; then the joint strategic decision search algorithm automatically identifies various models of appliances and analyzes the operating states of the electric appliances in homes or offices.
Liquid crystal lens structure and electrical controlling liquid crystal glasses structure thereof
(2015-01-06)
Chen Hung-Shan
;
Lin Yi-Hsin
A liquid crystal lens structure and an electrical controlling liquid crystal glasses structure are disclosed. The liquid crystal lens structure includes first electrode layer, compositing layer, second electrode layer and third electrode layer. The compositing layer includes first alignment layer, first liquid crystal layer, including thin-film layer, second liquid crystal layer and second alignment layer. The first alignment layer is disposed on the first electrode layer. The first liquid crystal layer is disposed on the first alignment layer. The compositing thin-film layer includes liquid crystal and polymer material and the compositing thin-film layer is disposed on the first liquid crystal layer. The second liquid crystal layer is disposed on the compositing thin-film layer. The second alignment layer is disposed on the second liquid crystal layer. The second electrode layer is disposed on the second alignment layer. The third electrode layers are disposed on the second electrode layer.
Cognitive radio communication system and operating method thereof
(2015-01-06)
Wu Sau-Hsuan
;
Chao Hsi-Lu
;
Ko Chun-Hsien
;
Mo Shang-Ru
;
Jiang Chang-Ting
A cognitive radio communication network is provided. The cognitive radio communication network includes a cloud and a wireless communication network.A communication system accessing to a backbone network is provided. The communication system includes a cloud and a wireless communication network connected to the cloud, and having a plurality of cognitive radio access points and a plurality of users, wherein the cloud performs the functions of network management, power control, and radio resource management.
Forming-free, bi-directional polarity conductive-bridge memory devices with Ge2Sb2Te5 solid-state electrolyte and Ag active electrode
(2015-01-07)
Huang, Yin-Hsien
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Chen, Hsuan-An
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Wu, Hsin-Han
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Hsieh, Tsung-Eong
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材料科學與工程學系
Preparation and characteristics of conductive-bridge random access memory devices containing Ge2Sb2Te5 (GST) chalcogenide as the solid-state electrolyte, Ag as the active electrode, and W-Ti as the counter electrode are presented. As revealed by the electrical measurement, only the samples containing crystalline GST exhibited the resistive switching behaviors. With an insertion of ZnS-SiO2 dielectric layer at the Ag/GST interface and a postannealing at 100 degrees C for 1 min, the sample exhibited the best electrical performance with satisfactory cycleability and retention properties. Moreover, the forming-free and bi-directional polarity features were observed in such a sample type. Microstructure and composition analyses found the finely dispersed nano-scale Ag clusters in GST and, when electrical bias is applied, the migrating Ag ions may build up the connections in between neighboring Ag clusters. Moreover, grain boundaries in polycrystalline GST might be the main paths for Ag migration. The thread-like conduction channels in GST hence form, leading to the low resistance state of sample. On the contrary, the depletion of Ag in GST broke the connections in between Ag clusters when the electrical bias is reversed. This led to the rupture of conduction channels and, hence, the high resistance state of sample. The low operational voltage, forming-free, and bi-directional polarity features observed in (AZGW)(T) sample might also originated from the fine dispersion of Ag clusters in GST electrolyte. (C) 2015 AIP Publishing LLC.
Cesium doping at C-60/rubrene heterointerfaces for improving the performance of organic light- and current-generating devices
(2015-01-07)
Cheng, Chiu-Ping
;
Lu, Meng-Han
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Chu, Yu-Ya
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Wei, Ching-Hsuan
;
Pi, Tun-Wen
This study examined the effect of adding cesium (Cs) at C-60/rubrene heterointerfaces by using synchrotron-radiation photoelectron spectroscopy. A C-60/rubrene heterostructure is the basis of a novel organic dual device found to facilitate efficient integration of both electroluminescent and photovoltaic functions. With Cs doping, the interfacial dipole potential was considerably enlarged, as was the separation between the lowest unoccupied molecular orbital of C-60 and the highest occupied molecular orbital of rubrene. However, the energy-level diagram indicated that a high Cs concentration prevents the formation of photoexcitons. By contrast, adding a small amount of Cs can effectively improve the efficiency of light-and current-generating devices. In particular, the deficiency of the dopants at the heterointerface may benefit the survival of photoexcitons. (C) 2015 AIP Publishing LLC.
RECEIVER AND RECEIVING METHOD FOR A COMBINERLESS LINC OFDM SYSTEM
(2015-01-08)
WU Wen Rong
;
CHENG Sheng-Lung
;
HSU Ying-Pei
A receiver and a receiving method for use in a LINC OFDM system are provided. The receiver receives a signal from a transmitter of the combinerless LINC OFDM system, generates a CP removed signal by removing a CP from the signal, generates a DFT signal by applying a DFT operation to the CP removed signal, generates a plurality of equalized symbols according to the DFT signal, generates a plurality of soft bits from the equalized symbols, generates a plurality of candidates regarding a transmitted bit sequence based on the soft bits by a list-Viterbi decoding algorithm, and decides an estimated transmitted bit sequence corresponding to the transmitted bit sequence from the candidates. The receiving method is able to perform the operations of the receiver.
Four-dimensional imaging of carrier interface dynamics in p-n junctions
(2015-01-09)
Najafi, Ebrahim
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Scarborough, Timothy D.
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Tang, Jau
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Zewail, Ahmed
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光電工程學系
The dynamics of charge transfer at interfaces are fundamental to the understanding of many processes, including light conversion to chemical energy. Here, we report imaging of charge carrier excitation, transport, and recombination in a silicon p-n junction, where the interface is well defined on the nanoscale. The recorded images elucidate the spatiotemporal behavior of carrier density after optical excitation. We show that carrier separation in the p-n junction extends far beyond the depletion layer, contrary to the expected results from the widely accepted drift-diffusion model, and that localization of carrier density across the junction takes place for up to tens of nanoseconds, depending on the laser fluence. The observations reveal a ballistic-type motion, and we provide a model that accounts for the spatiotemporal density localization across the junction.
Quantum criticality in a Kondo quantum dot coupled to helical edge states of interacting 2D topological insulators
(2015-01-09)
Chung, Chung-Hou
;
Silotri, Salman
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電子物理學系
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Department of Electrophysics
We investigate theoretically the quantum phase transition (QPT) between the one-channel Kondo (ICK) and two-channel Kondo (2CK) fixed points in a quantum dot coupled to helical edge states of interacting 2D topological insulators (2DTI) with Luttinger parameter 0 < K < 1. The model was studied by Law et al (2010 Phys. Rev. B 81 041305(R)), and was mapped onto an anisotropic two-channel Kondo model via bosonization. For K < 1, the strong coupling 2CK fixed point was argued to be stable for infinitesimally weak tunnelings between the dot and the 2DTI based on a simple scaling dimensional analysis (Law et al 2010 Phys. Rev. B 81 041305(R). We re-examine this model beyond the bare scaling dimension analysis via a one-loop renormalization group (RG) approach combined with bosonization and re-fermionization techniques near weak-coupling and strong-coupling (2CK) fixed points. We find for a fixed value of K < 1 that the 2CK fixed point can be unstable towards the 1CK fixed point and the system is expected to undergo a quantum phase transition between 1CK and 2CK fixed points with changing Kondo couplings. Our RG approach is controlled near K = 1. In general, this QPT can also occur upon tuning the Luttinger parameter K to a critical value K-c smaller than unity (0 < K-c < 1) for fixed Konodo couplings. The QPT in our model comes as a result of the combined Kondo and the helical Luttinger physics in 2DTI, and it serves as the first example of the 1CK-2CK QPT that is accessible by the controlled RG approach. We extract quantum critical and crossover behaviors from various thermodynamical quantities near the transition. Our results are robust against particle-hole asymmetry for 1/2 < K < 1.
The Index of Dry-Jet Wet Spinning for Polyacrylonitrile Precursor Fibers
(2015-01-10)
Wang, Tai-Yuan
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Chang, Hsiao-Chuan
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Chiu, Yu-Tsung
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Tsai, Jia-Lin
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機械工程學系
A new spinning index for a PAN precursor fiber is proposed that includes the viscosity of a spinning dope, the thermodynamic affinity, and the draw ratio during the spinning process. Through dry-jet wet spinning, six types of PAN precursor fibers with different spinning parameters, including solid content, solvent content in a bath, and draw ratio, were fabricated and analyzed with tensile tests, SEM, and XRD. The results show that the spinning index can reflect the mechanical properties of the fibers but is less indicative of crystallinity. Hence, the current spinning index is recommended for use as an indicator for the mechanical properties of PAN precursor fibers. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41265.
上橋式驅動電路
(2015-01-11)
陳宗麟
;
張翼
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成維華
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鄭泗東
;
鄭時龍
本發明係提供一上橋式驅動電路適用於上橋功率電晶體驅動，其包含一自舉式電路及一電位位準轉換器。在電位位準轉換器的設計中，利用二極體來限制其中的電晶體的汲極-源極電壓差，再利用電容來承受高電壓差。因此，驅動電路中不需要具高崩潰電壓的電晶體例如LDMOS。本發明可由一般的IC製程製作具高崩潰電壓的電容，因此所設計的驅動電路可整合於積體電路中。
用於顯示器之彩色畫素
(2015-01-11)
范士岡
;
邱誠樸
;
陳世強
一種用於顯示器之彩色畫素，包含：至少三個子畫素，每一個子畫素含有一個上載體、一個下載體、一個固定至該上載體之上電極、一個固定至該下載體之下電極、一個設置在該上及下電極之間的溶液，及多數個設置在該溶液內之粒子；其中，該等子畫素之粒子會在一特定驅動頻率下被電極化，且該等子畫素在顯示時可具有不同色彩；及該等子畫素之色彩分別透過該等子畫素之上載體、該等下載體、該等溶液或是該等粒子所提供。本發明之彩色畫素在應用至顯示器時，可顯示多樣且穩定的色彩變化。
丹磺醯衍生物之錯合物及其製法與應用
(2015-01-11)
王雲銘
;
林谷奎
一種丹磺醯衍生物之錯合物，是由下式(Ⅱ)所示： (II) 於式(Ⅱ)中，M、X、n及R1至R4的定義如說明書所述。本發明亦提供一種偵測一分析物中之過氧亞硝酸根離子的方法，包含使該分析物與一丹磺醯衍生物或該丹磺醯衍生物之錯合物反應，並量測所產生的螢光強度。本發明丹磺醯衍生物之錯合物可藉由量測螢光強度快速並專一性地偵測過氧亞硝酸根離子，且其不具有細胞毒性，並能有效偵測細胞中的過氧亞硝酸根離子。
服務啟動方法及系統
(2015-01-11)
林家瑜
;
陳昱嘉
;
王蒞君
;
曾煜棋
一種服務啟動方法及系統，此方法適用於包括感測器與資料擷取單元的電子裝置。此服務啟動方法包括下列步驟。首先，當感測器接收觸發訊號，判斷觸發訊號是否符合預設的觸發條件。若觸發訊號符合觸發條件，依據觸發條件判斷是否開啟資料擷取單元。當資料擷取單元開啟時，資料擷取單元接收輸入訊號。接著，辨識輸入訊號產生辨識資料。最後，判斷辨識資料是否符合預設的啟動條件，若判斷為是，啟動預設服務。
Vertical plasmonic resonance coupler
(2015-01-12)
Hsu, Yi-Jang
;
Lai, Yinchieh
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光電工程學系
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光電工程研究所
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Department of Photonics
Efficient wavelength-selective coupling of lights between subwavelength plasmonic waveguides and free space is theoretically investigated. The idea is based on a new type of vertical resonance coupling devices built on plasmonic metal/insulator/metal (MIM)waveguides. The device structure consists of a vertical grating coupler in a resonance cavity formed by two distributed Bragg reflectors (DBRs). With the metal loss included, maximum coupling efficiency around 50% can be obtained at the 1550 nm wavelength with a filtering 3dB bandwidth around 20 nm (7nm for the lossless case), demonstrating the feasibility of the idea for achieving high efficiency wavelength-selective vertical coupling through optical resonance. By utilizing this coupler, a plasmonic add-drop device is proposed and theoretically demonstrated. This kind of compact wavelength selective coupling devices shall have the potential to open up a new avenue of photonics circuitry at nanoscale. (C) 2015 Optical Society of America
Borate moiety-contained linker and bio-sensing element containing the same
(2015-01-13)
Li Yaw-Kuen
;
Shen Mo-Yuan
;
Pien Yu-Ju
A borate moiety-contained linker and a bio-sensing element containing the same are disclosed. The borate moiety-contained linker can be used to modify a sensing molecule and connect the sensing molecule to a substrate to form the bio-sensing element.
Method for fabricating thin-film transistor
(2015-01-13)
Lin Horng-Chih
;
Lyu Rong-Jhe
A method for fabricating a thin-film transistor is disclosed. Firstly, a patterned dielectric mask structure with a bottom thereof having a gate dielectric layer is formed on a gate-stacked structure so that the gate dielectric layer covers a gate of the gate-stacked structure. Top surface of the patterned dielectric mask structure has at least two openings. A semiconductor layer is formed on the gate-stacked structure via the openings by a sputtering method. The semiconductor layer comprises a channel above the gate, a source and a drain below the openings. The channel has a thickness which sequentially decreases from edge to center.
Enhanced Thermoelectric Performance of PEDOT:PSS Flexible Bulky Papers by Treatment with Secondary Dopants
(2015-01-14)
Mengistie, Desalegn A.
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Chen, Chang-Hsiao
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Boopathi, Karunakara M.
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Pranoto, Ferry W.
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Li, Lain-Jong
For inorganic thermoelectric materials, Seebeck coefficient and electrical conductivity are interdependent, and hence optimization of thermoelectric performance is challenging. In this work we show that thermoelectric performance of PEDOT:PSS can be enhanced by greatly improving its electrical conductivity in contrast to inorganic thermoelectric materials. Free-standing flexible and smooth PEDOT:PSS bulky papers were prepared using vacuum-assisted filtration. The electrical conductivity was enhanced to 640, 800, 1300, and 1900 S cm(-1) by treating PEDOT:PSS with ethylene glycol, polyethylene glycol, methanol, and formic acid, respectively. The Seebeck coefficient did not show significant variation with the tremendous conductivity enhancement being 21.4 and 20.6 mu V K-1 for ethylene glycol- and formic acid-treated papers, respectively. This is because secondary dopants, which increase electrical conductivity, do not change oxidation level of PEDOT. A maximum power factor of 80.6 mu W m(-1) K-2 was shown for formic acid-treated samples, while it was only 29.3 mu W m(-1) K-2 for ethylene glycol treatment. Coupled with intrinsically low thermal conductivity of PEDOT:PSS, ZT approximate to 0.32 was measured at room temperature using Harman method. We investigated the reasons behind the greatly enhanced thermoelectric performance.
Highly Thermal Stable and Efficient Organic Photovoltaic Cells with Crosslinked Networks Appending Open-Cage Fullerenes as Additives
(2015-01-14)
Chen, Chih-Ping
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Huang, Chien-Yu
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Chuang, Shih-Ching
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應用化學系
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Department of Applied Chemistry
Highly thermal stable organic bulk heterojunction (OBHJ) photovoltaic cells are demonstrated with crosslinkable open-cage fullerenes (COF) as additives in the active layer. Partial incorporation of COF, approximate to 10-15 wt% with weight ratio of P3HT:PC61BM = 1:0.9, builds up three-dimensional local borders upon heating treatment at 150 degrees C for 10 min. This process induces crosslinking chemical reaction through activating the styryl moiety in COF and reduces phase aggregation rates of fullerenes materials. Supported by statistics of devices degradation data analysis and optical microscopy study, the devices with COF show longer lifetime with keeping their efficiency (t = 144 h) under accelerated heating test at 150 degrees C, while PCE of normal devices without COF drop dramatically. These results demonstrate that the thermally crosslinkable COF is an excellent additive for highly thermal stable and durable OPVs applications.
Zinc Oxide Nanowire-Poly(Methyl Methacrylate) Dielectric Layers for Polymer Capacitive Pressure Sensors
(2015-01-14)
Chen, Yan-Sheng
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Hsieh, Gen-Wen
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Chen, Shih-Ping
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Tseng, Pin-Yen
;
Wang, Cheng-Wei
Polymer capacitive pressure sensors based on a dielectric composite layer of zinc oxide nanowire and poly(methyl methacrylate) show pressure sensitivity in the range of 2.63 x 10(-3) to 9.95 x 10(-3) cm(2) gf(-1). This represents an increase of capacitance change by as much as a factor of 23 over pristine polymer devices. An ultralight load of only 10 mg (corresponding to an applied pressure of similar to 0.01 gf cm(-2)) can be clearly recognized, demonstrating remarkable characteristics of these nanowire-polymer capacitive pressure sensors. In addition, optical transmittance of the dielectric composite layer is approximately 90% in the visible wavelength region. Their low processing temperature, transparency, and flexible dielectric film makes them a highly promising means for flexible touching and pressure-sensing applications.