Browsing by Issue Date, starting with "2015-08-03"

Now showing 1 - 20 of 21195

Collective modes, ac response, and magnetic properties of the three-dimensional Dirac semimetal in the triplet superconducting state
(2015-08-03)
Rosenstein, B.
;
Shapiro, B. Ya.
;
Shapiro, I.
;
電子物理學系
;
Department of Electrophysics
It was recently shown that conventional phonon-electron interactions may induce a triplet pairing state in time-reversal invariant three-dimensional Dirac semimetals. Starting from the microscopic model of the isotropic Dirac semimetal, the Ginzburg-Landau equations for the vector order parameter is derived using the Gor'kov technique. The collective modes including gapless Goldstone modes and gapped Higgs modes of various polarizations are identified. They are somewhat analogous to the modes in the B phase of He-3, although in the present case quantitatively there is a pronounced difference between longitudinal and transverse components. The difference is caused by the vector nature of the order parameter leading to two different coherence lengths or penetration depths. The system is predicted to be highly dissipative due to the Goldstone modes. The time-dependent Ginzburg-Landau model in the presence of external fields is used to investigate some optical and magnetic properties of such superconductors. The ac conductivity of a clean sample depends on the orientation of the order parameter. It is demonstrated that the difference between the penetration depths results in rotation of the polarization vector of microwave passing a slab made of this material. The upper critical magnetic field H-c2 was found. It turns out that at fields close to H-c2 the order parameter orients itself perpendicular to the field direction. In certain range of parameters the triplet superconducting phase persists at arbitrarily high magnetic field like in some p-wave superconductors.
Assessing the actual Gamma process quality - a curve-fitting approach for modifying the non-normal flexible index
(2015-08-03)
Liao, Mou-Yuan
;
Pearn, W. L.
;
Liu, Yen-Lun
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
Process capability indices (PCIs) have been widely adopted for quality assurance activities. By analysing PCIs, a production department can trace and improve a poor process to enhance product quality level and satisfy customer requirements. Among these indices, C-pk remains the most prevalent for facilitating managerial decisions because it can provide bounds on the process yield for normally distributed processes. However, processes are often non-normal in practice, and C-pk may quite likely misrepresent the actual product quality. Hence, the flexible index C-jkp, which considers possible differences in the variability above and below the target value, has been developed for practical use. However, C-jkp continues to suffer from serious bias in assessing actual capability, especially when the process distribution is highly skewed. In this paper, we modify C-jkp for assessing the actual process quality of a Gamma process. A correction factor is obtained by the curve-fitting method. The results show that our proposed method can significantly reduce the bias for calculation of actual nonconformities. Moreover, we introduce a sample estimator for our modified index. The ratio of this estimator\'s average value and the modified index is approximately 1. This implies that our proposed estimator can provide an appropriate estimation for assessing the actual Gamma process quality.
Application of porous oxide layer in plastic/metal direct adhesion by injection molding
(2015-08-03)
Yeh, Ren-Yu
;
Hsu, Ray-Quen
;
機械工程學系
;
Department of Mechanical Engineering
In this study, porous oxide layers were coated on aluminum sheets by plasma electrolytic oxidation (PEO) treatment. The PEO-treated aluminum sheets were then inserted and direct heated in the injection mold. The melting plastic penetrated and solidified in the micropores during the injection molding process, consequently achieving plastic/metal direct adhesion through micro-mechanical interlocking. The effects of the different surface morphologies of PEO coatings on plastic/metal adhesion were studied by shear test and microscopic characterizations. The microstructures were varied by changing PEO process parameters. The bonding strength was affected by the surface morphology changes, and the experimental results show that the surface porosity is a major factor in the direct adhesion. Reliable joints can be achieved on the porous coating, and the strength was proportional to the surface porosity. The shear strength in this study was in a range of approximately 3-8MPa with 7-20% surface porosity.
A Facile PDMS-Assisted Crystallization for the Crystal-Engineering of C-60 Single-Crystal Organic Field-Effect Transistors
(2015-08-05)
Wu, Kuan-Yi
;
Wu, Tzu-Yi
;
Chang, Shu-Ting
;
Hsu, Chain-Shu
;
Wang, Chien-Lung
交大e-News第191期-張懋中校長正式上任期許從頂尖邁向偉大
(2015-08-05)
國立交通大學秘書室
;
Secretariat
Performance improvement of high power liquid-cooled heat sink via non-uniform metal foam arrangement
(2015-08-05)
Chen, Kuan-Cheng
;
Wang, Chi-Chuan
;
機械工程學系
;
Department of Mechanical Engineering
The present study proposes a novel concept by employing non-uniform arrangements of metal foams alongside the heat sink applicable for liquid cooling. A total of 7 arrangements by varying PPI (pores per inch) of metal foam are made and additional 4 multiple channel designs are fabricated for comparison. Test results indicate that non-linearity term in Forchheimer equation rises significantly with increase of PPI (or with the decrease of permeability). The results suggest that the transition from the linear Darcy regime to the quadratic Forchheimer regime depends on the metal foam structure. It is also found that metal foam appreciably outperforms conventional multiple channel heat sink. The thermal resistance can be reduced by more than 62% as compared to that of empty plate design. For a given pumping power, the non-uniform arrangement of metal foam shows the best performance by employing a larger PPI metal foam at the inlet, followed by a smaller PPI metal foam, and the least PPI metal foam should be placed at the rear part of the heat sink. (C) 2015 Elsevier Ltd. All rights reserved.
Study of urinary 2-{[2-(acetylamino-2-carboxyethyl]sulfanyl}butanedioic acid, a mercapturic acid of rats treated with maleic acid
(2015-08-05)
Luo, Yu-Syuan
;
Tsai, Hsin-Yun
;
Chen, Hsin-Chang
;
Wu, Charlene
;
Shen, Li-Ching
Maleic anhydride was reported illegally adulterated into starch to prepare traditional foods for decades in Taiwan. Maleic acid (MA), hydrolyzed from maleic anhydride, could cause kidney damages to animals. The potential health effects due to long-term MA exposures through food consumption have been of great concerns. Assessment of the dietary MA exposures could be very difficult and complicated. One of the alternatives is to analyze an MA-specific biomarker to assess the daily total MA intake. Therefore, this paper aimed to study the mercapturic acid of MA, 2-{[2-(acetylamino)-2-carboxyethyl]sulfanyl} butanedioic acid (MAMA), with our newly-developed isotope-dilution online solid-phase extraction liquid chromatography tandem mass spectrometry (ID-SPE-LC-MS/MS) method. MAMA was first synthesized, purified, and characterized with NMR to reveal two diastereomers and used for developing the analytical method. The method was validated to reveal excellent sensitivity with a LOD at 16.3 ng/mL and a LOQ at 20.6 ng/mL and used to analyze MAMA in urine samples collected from Sprague-Dawley rats treated with a single dose of 0 mg/kg, 6 mg/kg, and 60 mg/kg (n = 5) of MA through gavage. Our results show dose-dependent increases in urinary MAMA contents, and 70% MAMA was excreted within 12 h with no gender differences (p > 0.05). A half life of urinary MAMA was estimated at 6.8 h for rat. The formation of urinary MAMA validates it as a chemically-specific biomarker for current MA exposure. Future study of MA metabolism in vivo will elucidate mechanisms of MAMA formation, and analysis of this marker in epidemiology studies could help to shed light on the causal effects of MA on human. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
High-resolution gravity and geoid models in Tahiti obtained from new airborne and land gravity observations: data fusion by spectral combination
(2015-08-05)
Shih, Hsuan-Chang
;
Hwang, Cheinway
;
Barriot, Jean-Pierre
;
Mouyen, Maxime
;
Correia, Pascal
For the first time, we carry out an airborne gravity survey and we collect new land gravity data over the islands of Tahiti and Moorea in French Polynesia located in the South Pacific Ocean. The new land gravity data are registered with GPS-derived coordinates, network-adjusted and outlier-edited, resulting in a mean standard error of 17 mu Gal. A crossover analysis of the airborne gravity data indicates a mean gravity accuracy of 1.7 mGal. New marine gravity around the two islands is derived from Geosat/ GM, ERS-1/GM, Jason-1/GM, and Cryosat-2 altimeter data. A new 1-s digital topography model is constructed and is used to compute the topographic gravitational effects. To use EGM08 over Tahiti and Moorea, the optimal degree of spherical harmonic expansion is 1500. The fusion of the gravity datasets is made by the band-limited least-squares collocation, which best integrates datasets of different accuracies and spatial resolutions. The new high-resolution gravity and geoid grids are constructed on a 9-s grid. Assessments of the grids by measurements of ground gravity and geometric geoidal height result in RMS differences of 0.9 mGal and 0.4 cm, respectively. The geoid model allows 1-cm orthometric height determination by GPS and Lidar and yields a consistent height datum for Tahiti and Moorea. The new Bouguer anomalies show gravity highs and lows in the centers and land-sea zones of the two islands, allowing further studies of the density structure and volcanism in the region.
OPTICAL SYSTEM AND ITS DISPLAY SYSTEM
(2015-08-06)
CHEN Hung-Shan
;
LIN Yi-Hsin
An optical system for aberration compensation comprising an optical module and an asymmetric refractive index distribution film is disclosed. The asymmetric refractive index distribution film comprises a liquid crystal and a liquid crystalline polymer, wherein the asymmetric refractive index distribution film set on an out-light surface or an in-light surface of the optical module. A display system comprising the above-mentioned optical system and an image panel are also disclosed herein. The asymmetric refractive index distribution film of the present invention has non-uniform refractive index distribution so as to effectively compensate the aberration formed by the optical module.
Novel transport function of adherens junction revealed by live imaging in Drosophila
(2015-08-07)
Li, Yu-Chiao
;
Yang, Wen-Ting
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Cheng, Lien-Chieh
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Lin, Chiao-Ming
;
Ho, Yu-Huei
Adherens junctions are known for their role in mediating cell cell adhesion. DE-cadherin and Echinoid are the principle adhesion molecules of adherens junctions in Drosophila epithelia. Here, using live imaging to trace the movement of endocytosed Echinoid vesicles in the epithelial cells of Drosophila embryos, we demonstrate that Echinoid vesicles co-localize and move with Rab5-or Rab11-positive endosomes. Surprisingly, these Echinoid-containing endosomes undergo directional cell-to-cell movement, through adherens junctions. Consistent with this, cell-to-cell movement of Echinoid vesicles requires the presence of DE-cadherin at adherens junctions. Live imaging further revealed that Echinoid vesicles move along adherens junction-associated microtubules into adjacent cells, a process requiring a kinesin motor. Importantly, DE-cadherin- and EGFR-containing vesicles also exhibit intercellular movement. Together, our results unveil a transport function of adherens junctions. Furthermore, this adherens junctions-based intercellular transport provides a platform for the exchange of junctional proteins and signaling receptors between neighboring cells. (C) 2015 Elsevier Inc. All rights reserved.
Experiencing affective music in eyes-closed and eyes-open states: an electroencephalography study
(2015-08-07)
Chang, Yun-Hsuan
;
Lee, You-Yun
;
Liang, Keng-Chen
;
Chen, I-Ping
;
Tsai, Chen-Gia
In real life, listening to music may be associated with an eyes-closed or eyes-open state. The effect of eye state on listeners' reaction to music has attracted some attention, but its influence on brain activity has not been fully investigated. The present study aimed to evaluate the electroencephalographic (EEG) markers for the emotional valence of music in different eye states. Thirty participants listened to musical excerpts with different emotional content in the eyes-closed and eyes-open states. The results showed that participants rated the music as more pleasant or with more positive valence under an eyes-open state. In addition, we found that the alpha asymmetry indices calculated on the parietal and temporal sites reflected emotion valence in the eyes-closed and eyes-open states, respectively. The theta power in the frontal area significantly increased while listening to emotional-positive music compared to emotional-negative music under the eyes-closed condition. These effects of eye states on EEG markers are discussed in terms of brain mechanisms underlying attention and emotion.
Electronic quenching of O(D-1) by Xe: Oscillations in the product angular distribution and their dependence on collision energy
(2015-08-07)
Garofalo, Lauren A.
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Smith, Mica C.
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Dagdigian, Paul J.
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Klos, Jacek
;
Alexander, Millard H.
The dynamics of the O(D-1) + Xe electronic quenching reaction was investigated in a crossed beam experiment at four collision energies. Marked large-scale oscillations in the differential cross sections were observed for the inelastic scattering products, O(P-3) and Xe. The shape and relative phases of the oscillatory structure depend strongly on collision energy. Comparison of the experimental results with time-independent scattering calculations shows qualitatively that this behavior is caused by Stueckelberg interferences, for which the quantum phases of the multiple reaction pathways accessible during electronic quenching constructively and destructively interfere. (C) 2015 AIP Publishing LLC.
Switchable viewing angle display with a compact directional backlight and striped diffuser
(2015-08-10)
Wang, Yi-Jun
;
Lu, Jian-Gang
;
Chao, Wei-Chung
;
Shieh, Han-Ping D.
;
光電工程學系
A compact high-directionality backlight module combined with a striped diffuser is proposed to achieve an adjustable viewing angle for ecodisplay. The micro-prisms on the compact light guide plate guide the emitting rays to the normal viewing angle, whereas a set of striped diffusers scatter the rays to a wide viewing angle. View cones of +/- 10 degrees/+/- 55 degrees were obtained for narrow/wide viewing modes with 88%/85% uniformity of spatial luminance, respectively. Compared with the conventional backlight, the optical efficiencies were increased by factors of 1.47 and 1.38 in narrow and wide viewing modes, respectively. In addition, only 5% of power consumption was needed when the backlight worked in private narrow viewing mode to maintain the same luminance as that of a conventional backlight. (C) 2015 Optical Society of America
Multi-indexed extensions of soliton potential and extended integer solitons of KdV equation
(2015-08-10)
Ho, Choon-Lin
;
Lee, Jen-Chi
;
電子物理學系
;
Department of Electrophysics
We calculate infinite set of initial profiles of higher integer Korteweg-de Vries (KdV) solitons, which are both exactly solvable for the Schrodinger equation and for the Gel\'fand-Levitan-Marchenko (GLM) equation in the inverse scattering transform (IST) method of KdV equation. The calculation of these higher integer soliton solutions is based on the recently developed multi-indexed extensions of the reflectionless soliton potential.
Size-dependent line broadening in the emission spectra of single GaAs quantum dots: Impact of surface charge on spectral diffusion
(2015-08-10)
Ha, Neul
;
Mano, Takaaki
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Chou, Ying-Lin
;
Wu, Yu-Nien
;
Cheng, Shun-Jen
Making use of droplet epitaxy, we systematically controlled the height of self-assembled GaAs quantum dots by more than one order of magnitude. The photoluminescence spectra of single quantum dots revealed the strong dependence of the spectral linewidth on the dot height. Tall dots with a height of similar to 30 nm showed broad spectral peaks with an average width as large as similar to 5 meV, but shallow dots with a height of similar to 2 nm showed resolution-limited spectral lines (<= 120 mu eV). The measured height dependence of the linewidths is in good agreement with Stark coefficients calculated for the experimental shape variation. We attribute the microscopic source of fluctuating electric fields to the random motion of surface charges at the vacuum-semiconductor interface. Our results offer guidelines for creating frequency-locked photon sources, which will serve as key devices for long-distance quantum key distribution.
Nanocontact Disorder in Nanoelectronics for Modulation of Light and Gas Sensitivities
(2015-08-11)
Lin, Yen-Fu
;
Chang, Chia-Hung
;
Hung, Tsu-Chang
;
Jian, Wen-Bin
;
Tsukagoshi, Kazuhito
To fabricate reliable nanoelectronics, whether by top-down or bottom-up processes, it is necessary to study the electrical properties of nanocontacts. The effect of nanocontact disorder on device properties has been discussed but not quantitatively studied. Here, by carefully analyzing the temperature dependence of device electrical characteristics and by inspecting them with a microscope, we investigated the Schottky contact and Mott's variable-range-hopping resistances connected in parallel in the nanocontact. To interpret these parallel resistances, we proposed a model of Ti/TiOx in the interface between the metal electrodes and nanowires. The hopping resistance as well as the nanocontact disorder dominated the total device resistance for high-resistance devices, especially at low temperatures. Furthermore, we introduced nanocontact disorder to modulate the light and gas responsivities of the device; unexpectedly, it multiplied the sensitivities compared with the intrinsic sensitivity of the nanowires. Our results improve the collective understanding of electrical contacts to low-dimensional semiconductor devices and will aid performance optimization in future nanoelectronics.
雙階排程方法、電腦程式產品
(2015-08-11)
林盈達
;
蔡明俊
;
王志強
;
賴源正
一種雙階排程方法，用於一電腦以排程多個專案，其中一排程規劃包括該些專案中的一第一專案，該第一專案包括第一工作，該雙階排程方法包括：根據該第一專案的一運轉時間、該第一專案的一離開時間、該第一工作的一服務時間、與一鬆弛因子來計算該第一工作的最晚開始時間；取得該些專案中的一第二專案，其中該第二專案包括多個第二工作；對於每一該些第二工作，取得至少一回填時間；對於每一該些第二工作，從對應的該至少一回填時間中挑選一第一回填時間，使得被延遲的該第一工作的該最晚開始時間大於等於該第一工作的一開始時間；以及將每一該些第二工作在對應的該第一回填時間加入至該排程規劃。
單脈衝雷達的比較器及其訊號產生方法
(2015-08-11)
黃瑞彬
;
郭芳銚
一種單脈衝雷達的比較器，包括：一天線陣列，包括N個天線，其中N為大於1的整數；一橫向電磁波模態空腔(TEM mode cavity)功率合成器，具有一合成埠與M個輸入埠組合，各該輸入埠組合具有一正相輸入埠與一反相輸入埠，其中M為大於1的整數；以及一切換裝置，耦接於該天線陣列與該橫向電磁波模態空腔功率合成器之間，用以將各該天線接收的回波訊號傳送至該些輸入埠組合的其中之一的該正相輸入埠或該反相輸入埠，其中，該橫向電磁波模態空腔功率合成器的該合成埠依據該些輸入埠組合各自的該正相輸入埠或該反相輸入埠所接收的該回波訊號產生一輸出訊號。
差量調變裝置
(2015-08-11)
吳重雨
;
呂元復
一種差量調變裝置，其用以接收一類比訊號，該類比訊號係為一多通道訊號，該類比訊號經由一多工器作為一通道訊號之選取，至少包含：一減法運算器，用以相減一輸出位元碼與一類比輸入訊號以產生一差值訊號；一第一類比數位轉換器，用以找出該差值訊號所落在之範圍內，其中該第一類比數位轉換器為一粗略估算類比數位轉換器，其用以估算該差值訊號之範圍，且設定多種範圍，以不改變，或改變一量化誤差以避免該訊號差值過大；一第二類比數位轉換器，用以根據第一類比數位轉換器之結果，以動態調整一量化步階大小，以量化該差值訊號，其中該第二類比數位轉換器為一精準解析類比數位轉換器，其係以二進位收尋方法，精準解析一差值電壓至最小位元，或使用者定義之最小單位為止；一記憶體單元，其中該記憶體單元為多通道記憶體；以及一數位加法器，用以累加該記憶體單元之一輸出位元碼，以及一數位輸出碼；其中，該減法運算單元與該粗略估算類比數位轉換器與該精準解析類比數位轉換器共同使用相同的二進制加權電容陣列，該數位加法器係輸出累加結果，並存入該記憶體單元，該第二類比數位轉換器係根據該第一類比數位轉換器之結果動態調整量化步階大小，以對該差值訊號作量化。
製造有機電子元件的裝置及其方法
(2015-08-11)
孟心飛
;
林皓武
;
洪勝富
;
冉曉雯
;
張浩文
一種製造一有機電子元件的方法，包含下列步驟：提供一基板；提供一第一熱源以加熱該基板；配置該有機電子元件的一膜材於該基板上；提供一第二熱源以加熱該膜材以形成一第一載子傳輸層；將含有一金屬離子之一材料摻雜於一有機材料中，並將其均勻地混合以形成一有機溶液；以及藉由具有複數微縫隙的一刮刀將該有機溶液塗佈，並且滾動或滑動該刮刀而使該有機溶液塗佈在該第一載子傳輸層上，以形成一第二載子傳輸層，其中該第二載子傳輸層為一電子傳輸層，且該第二載子傳輸層包含該有機材料與該金屬離子之材料。