Browsing by Issue Date, starting with "2014-07-18"

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A Highly Efficient Hybrid GaAs Solar Cell Based on Colloidal-Quantum-Dot-Sensitization
(2014-07-18)
Han, Hau-Vei
;
Lin, Chien-Chung
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Tsai, Yu-Lin
;
Chen, Hsin-Chu
;
Chen, Kuo-Ju
This paper presents a hybrid design, featuring a traditional GaAs-based solar cell combined with various colloidal quantum dots. This hybrid design effectively boosts photon harvesting at long wavelengths while enhancing the collection of photogenerated carriers in the ultraviolet region. The merits of using highly efficient semiconductor solar cells and colloidal quantum dots were seamlessly combined to increase overall power conversion efficiency. Several photovoltaic parameters, including short-circuit current density, open circuit voltage, and external quantum efficiency, were measured and analyzed to investigate the performance of this hybrid device. Offering antireflective features at long wavelengths and luminescent downshifting for high-energy photons, the quantum dots effectively enhanced overall power conversion efficiency by as high as 24.65% compared with traditional GaAs-based devices. The evolution of weighted reflectance as a function of the dilution factor of QDs was investigated. Further analysis of the quantum efficiency response showed that the luminescent downshifting effect can be as much as 6.6% of the entire enhancement of photogenerated current.
Are Normal Decision-Makers Sensitive to Changes in Value Contrast under Uncertainty? Evidence from the Iowa Gambling Task
(2014-07-18)
Lee, We-Kang
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Su, Yi-An
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Song, Tzu-Jiun
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Chiu, Yao-Chu
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Lin, Ching-Hung
The Iowa Gambling Task (IGT) developed by Bechara et al. in 1994 is used to diagnose patients with Ventromedial Medial Prefrontal Cortex (VMPFC) lesions, and it has become a landmark in research on decision making. According to Bechara et al., the manipulation of progressive increments of monetary value can normalize the performance of patients with VMPFC lesions; thus, they developed a computerized version of the IGT. However, the empirical results showed that patients\' performances did not improve as a result of this manipulation, which suggested that patients with VMPFC lesions performed myopically for future consequences. Using the original version of the IGT, some IGT studies have demonstrated that increments of monetary value significantly influence the performance of normal subjects in the IGT. However, other research has resulted in inconsistent findings. In this study, we used the computerized IGT (1X-IGT) and manipulated the value contrast of progressive increments (i.e., by designing the 10X-IGT, which contained 10 times of progressive increment) to investigate the influence of value contrast on the performance of normal subjects. The resulting empirical observations indicated that the value contrast (1X-vs. 10X-IGT) of the progressive increment had no effect on the performance of normal subjects. This study also provides a discussion of the issue of value in IGT-related studies. Moreover, we found the "prominent deck B phenomenon" in both versions of the IGT, which indicated that the normal subjects were guided mostly by the gain-loss frequency, rather than by the monetary value contrast. In sum, the behavioral performance of normal subjects demonstrated a low correlation with changes in monetary value, even in the 10X-IGT.
Maximally local connectivity and connected components of augmented cubes
(2014-07-20)
Chen, Y-Chuang
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Chen, Meng-Hung
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Tan, Jimmy J. M.
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資訊工程學系
;
Department of Computer Science
The connectivity of a graph is an important issue in graph theory, and is also one of the most important factors in evaluating the reliability and fault tolerance of a network. It is known that the augmented cube AQ is maximally connected, i.e. (2n - 1)-connected, for n >= 4. By the classic Menger\'s Theorem, every pair of vertices in AQ is connected by 2n - 1 vertex-disjoint paths for n >= 4. A routing with parallel paths can speed up transfers of large amounts of data and increase fault tolerance. Motivated by research on networks with faults, we obtained the result that for any faulty vertex set F c V(AQ) and [F] < 2n - 7 for n >= 4, each pair of non-faulty vertices, denoted by u and v, in AQ F is connected by min{deg(f)(u), deg(f) (v)} vertex-disjoint fault-free paths, where degf(u) and degf(v) are the degree of u and v in AQ(n) - F, respectively. Moreover, we demonstrate that for any faulty vertex set F subset of V(AQ(n)) and vertical bar F vertical bar < 4n - 9 for n 4, there exists a large connected component with at least 2(n) - vertical bar F vertical bar 1 vertices in AQ F, which improves on the results of Ma et al. (2008) who show this for n >= 6. (C) 2014 Elsevier Inc. All rights reserved.
辨識電器狀態的電力監控系統及其電力監控方法
(2014-07-21)
曹孝櫟
;
賴易聖
;
林明駿
;
陳勇旗
一種基於使用者參與及回饋之辨識電器狀態的電力監控系統及其電力監控方法。所述電力監控系統包括一第一電力監控裝置以及至少一第二電力監控裝置。第一及第二電力監控裝置分別測量第一電源及第二電源的電耗特性，藉以偵測第一變化及第二變化，第二電源為第一電源的分支。這些電力監控裝置進行一層次建構步驟以得知其相對位置，並同步校準第一變化及第二變化以計算第一電器變化。當偵測到第一電器變化時，第一電力監控裝置依據第一電器變化搜尋電器特徵資料庫來取得並監控相似第一電器變化的第一電器的狀態。
Observation of the high-sensitivity plasmonic dipolar antibonding mode of gold nanoantennas in evanescent waves
(2014-07-21)
Chen, Yi-Hsun
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Chen, Kuo-Ping
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Shih, Min-Hsiung
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Chang, Che-Yuan
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照明與能源光電研究所
Plasmonic dipolar antibonding modes of gold nanoantennas are observed in evanescent waves. Comparing with the bonding mode for normal incidence, the use of prism coupling to transfer the energy of incident light to plasmonic resonance in nanoantennas not only has a higher extinction coefficient but also achieves higher sensitivity to the surrounding environment. The sensitivity of the antibonding mode of gold nanoantenna is 4.84 times that of the bonding mode in terms of the figure of merit. (C) 2014 AIP Publishing LLC.
一種用以處理循環碼之方法及裝置
(2014-07-21)
林義閔
;
楊其衡
;
張錫嘉
;
李鎮宜
一種用以處理循環碼之方法及裝置在此揭露，其中之裝置包括至少一可重組態模組與一編碼控制器，可重組態模組包括多個線性回饋移位暫存器。編碼控制器用以控制可重組態模組去將生成多項式轉換成因式分解多項式。於可重組態模組中，多個線性回饋移位暫存器分別暫存此因式分解多項式之多個因式。
半導體製程方法
(2014-07-21)
吳耀銓
;
陳俞中
本發明提供一種半導體製程方法，包含下列步驟：提供一成長基板；形成一凹凸結構於該成長基板上；形成一半導體元件層於該凹凸結構上；以及改變該成長基板與該半導體元件層的溫度。
交大e-News第167期
(2014-07-21)
Secretariat
;
國立交通大學秘書室
遠距收音裝置
(2014-07-21)
白明憲
;
王俊凱
本發明提供一種遠距收音裝置，包括至少一麥克風、至少一號角收音器及一自動增益控制模組，利用麥克風接收外部聲音，而號角收音器設於麥克風之前端可增加麥克風收音之指向性並抑制環境噪音；自動增益控制模組設於麥克風中或一主機中，依據麥克風所接收之外部聲音之音量大小，比對一統計曲線找出最適當的增益值，對外部聲音進行音訊增益。
Observation of the high-sensitivity plasmonic dipolar antibonding mode of gold nanoantennas in evanescent waves
(2014-07-21)
Chen, Yi-Hsun
;
Chen, Kuo-Ping
;
Shih, Min-Hsiung
;
Chang, Che-Yuan
;
照明與能源光電研究所
Plasmonic dipolar antibonding modes of gold nanoantennas are observed in evanescent waves. Comparing with the bonding mode for normal incidence, the use of prism coupling to transfer the energy of incident light to plasmonic resonance in nanoantennas not only has a higher extinction coefficient but also achieves higher sensitivity to the surrounding environment. The sensitivity of the antibonding mode of gold nanoantenna is 4.84 times that of the bonding mode in terms of the figure of merit. (C) 2014 AIP Publishing LLC.
可供製造高電遷性電晶體之結構、包含此結構的元件及其之製造方法
(2014-07-21)
張翼
;
吳雲驥
;
林岳欽
所揭示者為一種適合做為半導體元件之砷化鎵金氧半導體假型高電遷性電晶體(MOS-PHEMT)的結構，及一種製造此結構的方法。此MOS-PHEMT結構的特徵在於具有一層以原子層沉積方式形成的閘極介電質，且該閘極介電質是由以下任一種材料製成：Al2O3、HfO2、La2O3或ZrO2；使得包含此MOS-PHEMT結構的元件，例如高頻開關元件，具有較低的閘極漏電流、較少的直流電力損耗、較少的衰減損耗以及較佳的隔絕性質。
Testing system and method of metal sheet
(2014-07-22)
Hung Chinghua
;
Chen Yan-Yo
;
Tsai Yu-Chung
The present invention provides a testing system of metal sheet, and the system at least comprises a clipping apparatus, a hydraulic press apparatus and a measuring apparatus. The clipping apparatus comprises a first mold, a second mold and a hyperelastic plate. The hydraulic press apparatus connects to the clipping apparatus and transfer a hydraulic pressure via the second mold to the one of the testing sheet set to let it bulge along an orientation toward the first mold. The measuring apparatus connects with the clipping apparatus and the hydraulic press apparatus separately to measure a momentary pressure of the hydraulic pressure and the bulge height of the one of the testing sheet set. A testing method using the abovementioned system is also disclosed in the present invention.
Rapid channelization and incision into soft bedrock induced by human activity - Implications from the Bachang River in Taiwan
(2014-07-22)
Huang, Ming-Wan
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Liao, Jyh-Jong
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Pan, Yii-Wen
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Cheng, Meng-Hsiung
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土木工程學系
Many Taiwanese river channels have been affected by human activity, such as engineering works and gravel mining. Environmental conditions such as high seasonal precipitation and young sedimentary bedrock exaggerate the narrowing and incising of river channels. The Bachang River is located in southwestem Taiwan, and the 11-km-long channel at its midstream reach has been incised to a maximum depth of approximately 30 m within several decades. Therefore, the morphologic evolution of the Bachang River in southwestern Taiwan provides an illustration of channel changes in response to human activity. The historical data used for this analysis of morphology change include one set of topographic maps and six sets of aerial photographs from the past 100 years. The channel changes are analyzed qualitatively and quantitatively and include the channel planform, longitudinal profiles, channel incision, channel width, and channel cross sections. The results indicate that remarkable channel changes have occurred since the 1980s as a result of human influence. The 11-km-long study reach transformed from an alluvial-type channel to a gorge-type channel within several decades. The maximum accumulated depth of the channel incision is approximately 30 m, with a meter-scale annual average incision rate; the maximum width has been decreased to approximately one-sixth of the original width (448 m). The process of channel evolution is divided into four stages, and we have concluded that the causes of channel change include six factors from two categories: natural factors that include geological conditions, hydrological conditions, and the process of bedrock erosion; and human factors that include gravel mining, lateral structures, and levees. The initiation of channel evolution is triggered by human factors. Finally, we discuss the potential future channel evolution and lessons learned from the case study. (C) 2014 Elsevier B.V. All rights reserved.
Graphene/MoS2 Heterostructures for Ultrasensitive Detection of DNA Hybridisation
(2014-07-23)
Phan Thi Kim Loan
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Zhang, Wenjing
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Lin, Cheng-Te
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Wei, Kung-Hwa
;
Li, Lain-Jong
The photoluminescence signals of a graphene/MoS2 heterostructural stacking film are sensitive to environmental charges, which allows the single-base sequence-selective detection of DNA hybridization with sensitivity to the level of aM. [GRAPHICS] .
KDM4B as a Target for Prostate Cancer: Structural Analysis and Selective Inhibition by a Novel Inhibitor
(2014-07-24)
Chu, Chia-Han
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Wang, Ling-Yu
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Hsu, Kai-Cheng
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Chen, Chung-Chin
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Cheng, Hsing-Hung
The KDM4/JMJD2 Jumonji C-containing histone lysine demethylases (KDM4A-KDM4D), which selectively remove the methyl group(s) from tri/dimethylated lysine 9/36 of H3, modulate transcriptional activation and genome stability. The overexpression of KDM4A/KDM4B in prostate cancer and their association with androgen receptor suggest that KDM4A/KDM4B are potential progression factors for prostate cancer. Here, we report the crystal structure of the KDM4B.pyridine 2,4-dicarboxylic acid. H3K9me3 ternary complex, revealing the core active-site region and a selective K9/K36 site. A selective KDM4A/KDM4B inhibitor, 4, that occupies three subsites in the binding pocket is identified by virtual screening. Pharmacological and genetic inhibition of KDM4A/KDM4B significantly blocks the viability of cultured prostate cancer cells, which is accompanied by increased H3K9me3 staining and transcriptional silencing of growth-related genes. Significantly, a substantial portion of differentially expressed genes are AR-responsive, consistent with the roles of KDM4s as critical AR activators. Our results point to KDM4 as a useful therapeutic target and identify a new inhibitor scaffold.
Structural and nanoindentation studies of epitaxial titanium oxynitride (001) films grown on MgO(001) substrate
(2014-07-25)
Do, Hien
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Van-Truong Dai
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Tian, Jr-Sheng
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Yen, Tzu-Chun
;
Chang, Li
We investigate the effect of chemical composition and residual stress on the mechanical properties of high-quality epitaxial TiNxOy films deposited on MgO(001) substrates by using nanoindentation. The lattice parameters and residual strain/stress of TiNxOy films decrease as oxygen concentration increases. Hardness and Young\'s modulus determined by nanoindentation are about 17-26 GPa and 355-430 GPa, respectively, which vary with chemical composition and residual stress. (C) 2014 Elsevier B.V. All rights reserved.
Submicron organic thin-film transistors fabricated by film profile engineering method
(2014-07-28)
Wu, Ming-Hung
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Lin, Horng-Chih
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Lin, Hung-Cheng
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Zan, Hsiao-Wen
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Meng, Hsin-Fei
In this work, we explore and demonstrate the feasibility of a film profile engineering (FPE) concept in fabricating pentacene-based organic thin-film transistors (OTFTs) with submicron channel length. The FPE scheme utilizes a suspended bridge built on the wafer and the specific deposition conditions to form thin films with desirable profiles. In order to form a continuous pentacene channel under the bridge, the background pressure of thermal evaporator is adjusted by pumping down the filling N-2 to a specific level. The results show that, by setting the deposition pressure at 3 mtorr, functional operations of OTFTs with channel length ranging from 0.4 to 0.6 mu m are obtained. (C) 2014 AIP Publishing LLC.
Long-range electron-electron interactions in graphene make its electrodynamics nonlocal
(2014-07-28)
Rosenstein, B.
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Kao, H. C.
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Lewkowicz, M.
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電子物理學系
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Department of Electrophysics
Graphene, a one-layer-thick hexagonal array of carbon atoms, when undoped, exhibits a curious mixture of properties pertinent to either metals or insulators. On the one hand, despite near absence of both charge carriers and impurities, it has a finite conductivity like a metal. On the other hand, the Coulomb interaction between electrons is unscreened like in a dielectric and hence is long range. The chemical potential is pinned right between the conical valence and conduction bands causing quasiparticles to move like massless relativistic particles. We demonstrate at small coupling that the electrodynamics of graphene exhibits nonlocality on a macroscopic level due to the combination of the long-range interactions and the linear dispersion relation. The frequency and wave vector k-dependent conductivity tensor, in addition to a local pseudo-Ohmic part sigma(T)delta(ij), possesses a nonlocal contribution sigma(n1)k(i)k(j)/k(2). While the coefficient of the local part is sigma(T) approximate to e(2)/4 (h) over bar, the coefficient of the nonlocal part is proportional to the Coulomb interaction strength alpha, sigma(n1) = sigma(T)alpha. This leads to several remarkable effects in transport and optical response. In particular, the resistance of the graphene flake depends on the location and the geometry of the source, drain, and probes. A voltage perpendicular to the current appears in a time-reversal symmetric situation and the polarization of reflected and transmitted light is modified, without either the magnetic field (like in the Faraday effect) or anisotropy.
Resistive random access memory (RRAM) using stacked dielectrics and method for manufacturing the same
(2014-07-29)
Chin Albert
;
Cheng Chun-Hu
Resistive random access memory (RRAM) using stacked dielectrics and a method for manufacturing the same are disclosed, where a setting power of only 4 μW, an ultra-low reset power of 2 nW, good switching uniformity and excellent cycling endurance up to 5×109 cycles were achieved simultaneously. Such record high performances were reached in a Ni/GeOx/nano-crystal-TiO2/TaON/TaN RRAM device, where the excellent endurance is 4˜6 orders of magnitude larger than existing Flash memory. The very long endurance and low switching energy RRAM is not only satisfactory for portable SSD in a computer, but may also create new applications such as being used for a Data Center to replace high power consumption hard discs.
Femtosecond Infrared Transient Absorption Dynamics of Benzimidazole-Based Ruthenium Complexes on TiO2 Films for Dye-Sensitized Solar Cells
(2014-07-31)
Hsu, Hung-Yu
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Cheng, Chi-Wen
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Huang, Wei-Kai
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Lee, Yuan-Pern
;
Diau, Eric Wei-Guang
By means of femtosecond infrared transient absorption spectra, we measured the interfacial electron-transfer dynamics for benzimidazole-based heteroleptic ruthenium dyes (RIDS, RD12, RD15-RD18) sensitized on TiO2 thin films. For all measurements, the first singlet metal-to-ligand charge-transfer states ((MLCT)-M-1) of the ruthenium complexes were excited at 519 nm and the injected electrons in the conduction band of TiO2 were probed at 4.3 mu m. All transient signals featured two rising components on a femtosecond-picosecond scale due to a two-step electron injection and an offset (N719, RD16-RD18) or a slow-decay (RD5, RD12, and RD15) component on a nanosecond microsecond scale due to a back electron transfer. A complicated two-step kinetic model was derived analytically to interpret the observed two rising components for which the rapid (tau(1) < 300 fs) and slow (tau(2) = 10-20 ps) electron injections arose from the singlet (MLCT)-M-1 and triplet (MLCT)-M-3 states, respectively. The amplitudes of the two electron-injection components (A(1) and A(2)) were controlled by the rate coefficient of the (MLCT)-M-1 --> (MLCT)-M-3 intersystem crossing; the variations of A(1) and A(2) are consistent with the trend of the corresponding Stokes shifts rationalized with a conventional energy-gap law for nonradiative transitions. Compared with the kinetics observed for the N719 dye, the involvement of a benzimidazole ligand in RD dyes had the effect of accelerating the two electron injections, thus improving the short circuit current of the device. RD dyes substituted with fluorine atoms and/or thiophene units in the benzirnidazole ligands showed a retardation of 3MLCT electron injection relative to that of the nonsubstituted RD5 dye. Acceleration of the BET process was observed for the RD5 dye (9 ns), and both fluoro-substituted dyes (14 ns for RD12 and 21 ns for RD15) and thiophene-substituted dyes (nonobservable for RD16-RD18) had significantly retarded BET kinetics. The observed kinetics of the (MLCT)-M-3 electron injection for all RD dyes is satisfactorily simulated with the Marcus theory.