Browsing by Issue Date, starting with "2017-08-28"

Now showing 1 - 20 of 13303

Controlled self-assemblies of polystyrene-block-polydimethylsiloxane micelles in cylindrical confinement through a micelle solution wetting method and Rayleigh-instability-driven transformation
(2017-08-28)
Ko, Hao-Wen
;
Higuchi, Takeshi
;
Chang, Chun-Wei
;
Cheng, Ming-Hsiang
;
Isono, Komei
Block copolymer micelles have been extensively discussed for many decades because of their applications, such as lithography and drug delivery. However, controlling the morphologies of nanostructure assembly using block copolymer micelles as building elements remains a great challenge. In this work, we developed a novel route to induce micelle assembly in confined geometries. Polystyrene-block-polydimethylsiloxane (PS-b-PDMS) micelle solutions were used to prepare micelle nanostructures, and the critical parameters affecting the morphologies were determined. Micelle nanorods, micelle nanospheres, and multi-component nanopeapods were prepared by wetting anodic aluminum oxide (AAO) templates with micelle solutions. Rayleigh-instability-driven transformation was discovered to play an important role in controlling the morphologies of the micelle nanostructures. This study not only proposes a versatile approach to preparing block copolymer micelle nanostructures, but it also provides deeper insight into the controlling factors of block copolymer micelle morphologies in cylindrical confinement.
Significant color space blue-shift of green OLED emitter with sustaining lifetime and substantial efficiency enhancement
(2017-08-28)
Li, Jung-Yu
;
Chen, Shih-Pu
;
Siao, Huei-Jhen
;
Wu, Jin-Han
;
Chen, Guan-Yu
In this study, we demonstrate that by embedding a plasmonic coupling metal layer beneath the active layer of an organic light-emitting diode, the resultant device is capable of inducing significant blue shifts in CIE color space coordinates of emitting light from the green emitting material without compromising the lifetime of the parent material. The implemented device consists of multilayers of organic emitting materials sandwiched by two thin metal layers to form a metal-dielectric-metal (MDM) cavity-like structure. The original green emission with CIE coordinates of (0.22, 0.56) was significantly color space blue-shifted to CIE coordinates of (0.10, 0.53). The MDM device exhibits an efficiency of 62 cd/A at a luminance of 1000 cd/m(2), which represents a two-fold enhancement of current efficiency. Moreover, the spectral peak intensity is 4.3 times higher than that in a conventional device, which is much higher than that expected for an optical microcavity model, suggesting that the Purcell effect resulting from the coupling of surface plasmon waves may contribute to the extra enhancement of emission intensity. Published by AIP Publishing.
AC stress and electronic effects on SET switching of HfO2 RRAM
(2017-08-28)
Liu, Jen-Chieh
;
Magyari-Kope, Blanka
;
Qin, Shengjun
;
Zheng, Xin
;
Wong, H. -S. Philip
An AC stress test was performed to investigate the accompanying electronic effects in a HfO2 resistive random access memory during the SET transition, which featured a sudden decrease in resistance. Comparing the DC and AC measurement results indicated the pronounced influence of interrupted stress on both the mean values and variations of time to SET. First-principles calculations suggested that the charge states (+2, +1, or neutral) of oxygen vacancies affect the migration barrier for forming oxygen vacancy clusters. Therefore, a charge-state-dependent SET model is proposed to include the additional electronic effects induced by the dynamics of electron trapping and detrapping in oxygen vacancies during AC stress. A trimodal Weibull fitting based on the proposed model reproduced the experimental time to SET distributions obtained in a wide range of AC stress conditions. Published by AIP Publishing.
Gate tunable spin-orbit coupling and weak antilocalization effect in an epitaxial La2/3Sr1/3MnO3 thin film
(2017-08-28)
Chiu, Shao-Pin
;
Yamanouchi, Michihiko
;
Oyamada, Tatsuro
;
Ohta, Hiromichi
;
Lin, Juhn-Jong
Epitaxial La2/3Sr1/3MnO3 (LSMO) films have been grown on SrTiO3 (001) substrates via pulsed laser deposition. In a 22-nm-thick LSMO film with a low residual resistivity of rho(0) approximate to 59 mu Omega cm, we found a zero-field dip in the magnetoresistance (MR) below 10 K, manifesting the weak antilocalization (WAL) effect due to strong spin-orbit coupling (SOC). We have analyzed the MR data by including the D'yakonov-Perel' spin-relaxation mechanism in the WAL theory. We explain that the delocalized spin-down electron sub-band states play a crucial role for facilitating marked SOC in clean LSMO. Moreover, we find that the SOC strength and gate voltage tunability are similar to those in a two-dimensional electron gas at the LaAlO3/SrTiO3 interface, indicating the presence of an internal electric field near the LSMO/SrTiO3 interface. In a control measurement on a 5-nm-thick high resistivity (rho(0) approximate to 280 mu Omega cm) LSMO film, we observe only a small zero-field peak in MR from weak localization effect, indicating negligible SOC.
Hyperscaling violating black hole solutions and magneto-thermoelectric DC conductivities in holography
(2017-08-28)
Ge, Xian-Hui
;
Tian, Yu
;
Wu, Shang-Yu
;
Wu, Shao-Feng
;
電子物理學系
We derive new black hole solutions in Einstein-Maxwell-axion-dilaton theory with a hyperscaling violation exponent. We then examine the corresponding anomalous transport exhibited by cuprate strange metals in the normal phase of high-temperature superconductors via gauge-gravity duality. Linear-temperature-dependence resistivity and quadratic-temperature-dependence inverse Hall angle can be achieved. In the high-temperature regime, the heat conductivity and Hall Lorenz ratio are proportional to the temperature. The Nernst signal first increases as temperature goes up, but it then decreases with increasing temperature in the high-temperature regime.
Co-delivery of paclitaxel and cetuximab by nanodiamond enhances mitotic catastrophe and tumor inhibition
(2017-08-29)
Lin, Yu-Wei
;
Raj, Emmanuel Naveen
;
Liao, Wei-Siang
;
Lin, Johnson
;
Liu, Kuang-Kai
The poor intracellular uptake and non-specific binding of anticancer drugs into cancer cells are the bottlenecks in cancer therapy. Nanocarrier platforms provide the opportunities to improve the drug efficacy. Here we show a carbon-based nanomaterial nanodiamond (ND) that carried paclitaxel (PTX), a microtubule inhibitor, and cetuximab (Cet), a specific monoclonal antibody against epidermal growth factor receptor (EGFR), inducing mitotic catastrophe and tumor inhibition in human colorectal cancer (CRC). ND-PTX blocked the mitotic progression, chromosomal separation, and induced apoptosis in the CRC cells; however, NDs did not induce these effects. Conjugation of ND-PTX with Cet (ND-PTX-Cet) was specifically binding to the EGFR-positive CRC cells and enhanced the mitotic catastrophe and apoptosis induction. Besides, ND-PTX-Cet markedly decreased tumor size in the xenograft EGFR-expressed human CRC tumors of nude mice. Moreover, ND-PTX-Cet induced the mitotic marker protein phospho-histone 3 (Ser10) and apoptotic protein active-caspase 3 for mitotic catastrophe and apoptosis. Taken together, this study demonstrated that the co-delivery of PTX and Cet by ND enhanced the effects of mitotic catastrophe and apoptosis in vitro and in vivo, which may be applied in the human CRC therapy.
Functional Connectivity of the Corpus Callosum in Epilepsy Patients with Secondarily Generalized Seizures
(2017-08-30)
Peng, Syu-Jyun
;
Hsin, Yue-Loong
;
電子工程學系及電子研究所
;
生醫電子轉譯研究中心
;
Department of Electronics Engineering and Institute of Electronics
The corpus callosum (CC) plays an important role in generalization of seizure activity. We used resting-state function magnetic resonance imaging (rs-fMRI) to investigate the regional and interregional functional connectivity of CC in patients with magnetic resonance imaging (MRI)-negative and secondarily generalized seizures. We measured the multi-regional coherences of blood oxygen level-dependent (BOLD) signals via rs-fMRI, cortical thickness via high-resolution T1-weighted MRI, and white matter (WM) integrity via diffusion-tensor imaging in 16 epilepsy patients as well as in 16 age-and gender-matched healthy subjects. All patients had non-lesional MRI, medically well-controlled focal epilepsy and history of secondarily generalized convulsions. Individuals with epilepsy had significant differences in regional and interregional hypersynchronization of BOLD signals intrahemispherically and interhemispherically, but no difference in cortical thickness and WM integrity. The only area with increased regional hypersynchrony in WM was over the anterior CC, which also exhibited lower activation of neighboring resting-state networks. The present study revealed abnormal local and distant synchronization of spontaneous neural activities in epileptic patients with secondarily generalized seizures.
NERVE IMPULSE SIGNAL STIMULATION DEVICE AND METHOD FOR FABRICATING THE SAME
(2017-08-31)
Yu-Ting Cheng
;
Chung-Yu Wu
;
Jui-Sheng Sun
;
Yu-Min Fu
;
Che-Yu Chen
A nerve impulse signal stimulation device and a method for fabricating the same are provided. The nerve impulse signal stimulation device includes: a substrate having a first surface and a second surface opposite to the first surface; a first metal layer formed on the first surface of the substrate; a second metal layer formed on the first metal layer; a plurality of openings exposing a portion of the first surface of the substrate, a portion of the first metal layer and a portion of the second metal layer; and a ferromagnetic material attached to the second surface of the substrate. The openings cause the nerve impulse signal stimulation device to obtain a parallel circuit structure, thereby increasing the current load and the magnetic field intensity, reducing the size of the device, and ensuring the safety of operations.
METHOD FOR PROCESSING IMAGE WITH DEPTH INFORMATION AND COMPUTER PROGRAM PRODUCT THEREOF
(2017-08-31)
Jiun-In GUO
;
Po-Yu CHIEN
The present invention proposes a method for processing an image with depth information and a computer program product thereof, wherein a filtering template is used to extract a gesture region and filter the image, and wherein the hue values of the pixels of the current gesture region are used to modify the self-adaptive thresholds of the filtering template, and wherein the size of the filtering template at the next time point is modified according to the depth at the current time point and the depth at the former time point.
Negative correlation of cortical thickness with the severity and duration of abdominal pain in Asian women with irritable bowel syndrome
(2017-08-31)
Chua, Chian Sem
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Bai, Chyi-Huey
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Shiao, Chen-Yu
;
Hsu, Chien-Yeh
;
Cheng, Chiao-Wen
Background & aims: Irritable bowel syndrome (IBS) manifests as chronic abdominal pain. One pathophysiological theory states that the brain-gut axis is responsible for pain control in the intestine. Although several studies have discussed the structural changes in the brain of IBS patients, most of these studies have been conducted in Western populations. Different cultures and sexes experience different pain sensations and have different pain responses. Accordingly, we aimed to identify the specific changes in the cortical thickness of Asian women with IBS and to compare these data to those of non-Asian women with IBS. Methods: Thirty Asian female IBS patients (IBS group) and 39 healthy individuals (control group) were included in this study. Brain structural magnetic resonance imaging was performed. We used FreeSurfer to analyze the differences in the cortical thickness and their correlations with patient characteristics. Results: The left cuneus, left rostral middle frontal cortex, left supramarginal cortex, right caudal anterior cingulate cortex, and bilateral insula exhibited cortical thinning in the IBS group compared with those in the controls. Furthermore, the brain cortical thickness correlated negatively the severity as well as duration of abdominal pain. Conclusions: Some of our findings differ from those of Western studies. In our study, all of the significant brain regions in the IBS group exhibited cortical thinning compared with those in the controls. The differences in cortical thickness between the IBS patients and controls may provide useful information to facilitate regulating abdominal pain in IBS patients. These findings offer insights into the association of different cultures and sexes with differences in cortical thinning in patients with IBS.
Phosphonic Acid and Lithium Salt as Effective p-Dopants to Oxidize Spiro-OMeTAD for Mesoscopic Sb2S3 Solar Cells
(2017-08-31)
Chung, Chih-Chun
;
Tsai, Ting -Wei
;
Wu, Hui -Ping
;
Diau, Eric Wei-Guang
;
應用化學系
1-Decyl phosphonic acid (DPA) proved an effective p-doping additive to oxidize spiro-OMeTAD as a hole-transporting material (HTM) for nanostructured Sb2S3 extremely thin absorber (ETA) solar cells. DPA had the effect of enhancing the hole conductivities of spiro-OMeTAD in the presence of lithium bis(trifluoromethyl- sulfonyl)-imide (LiTFSI) to significantly improve the device performance. Transient photoelectric measurements and electrochemical impedance spectra of devices fabricated with varied additive conditions provided information about the charge- transport and recombination kinetics and hole conductivities for Sb2S3 devices with additives DPA and LiTFSI that exhibited superior performance. Thirty-five identical devices were fabricated to show the excellent reproducibility and long-term stability in air; the best Sb2S3 ETA device attained efficiency of power conversion 6.0%, which is twice that of a device using other typical additives (LiTFSI and 4-tert-butyl-pyridine) for spiro-OMeTAD serving as HTM.
Optical properties of plasma-enhanced chemical vapor deposited SiCxNy films by using silazane precursors
(2017-08-31)
Chang, Wei-Yuan
;
Chang, Chieh-Yu
;
Leu, Jihperng
;
材料科學與工程學系
;
Department of Materials Science and Engineering
In this study, amorphous silicon carbonitride (SiCxNy) films were fabricated by radio frequency (RF) chemical vapor deposition (PECVD) using a single silazane precursor and a low power density (0.15W/cm(3)) for better compositional control. The effects of the precursor chemical structure (C/Si ratio, C-Si-N structure, and vinyl groups) and deposition temperature (T-s) on the chemical structure and optical properties of SiCxNy films were examined using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Specifically, two new single precursors; namely, n-methyl-aza-2,2,4-trimethylsilacyclopentane (MTSCP) and 1,3-divinyl-1,1,3,3-tetramethyl-disilazane (DVTMDS) were studied and compared. SiCxNy films deposited using MTSCP involving Si-C-3-N rings formed Si-N and Si-(CH2)(3)-crosslinked structures at T-s <= 100 degrees C, and were then changed to predominantly Si-CH2-N-Si crosslinked structures at Ts > 300 degrees C, leading to a wide range of optical band gap from 5.2 to 3.7 eV. Compared to DVTMDS-deposited SiCxNy films, their relatively higher percentage of Si-C-N structure accounted for the lower optical band gap and reduced transmission. DVTMDS with di-vinyl groups readily formed a Si-(CH2)(2)-bridge in SiCxNy films Ts <= 200 degrees C, resulting in excellent optical transmittance. The transmittance in the visible wavelengths of 400 degrees C-deposited SiCxNy film using DVTMDS still showed 85%. Also, tunable refractive index between 1.44 and 2.10 were obtained for SiCxNy films deposited at T-s <= 400 degrees C. (c) 2017 Elsevier B.V. All rights reserved.
【活動花絮】新資訊時代的女力關鍵
(國立交通大學資訊學院, 2017-09)
林珮雯
106 年 4 月 8 日是交通大學創校 121 週年暨在台建校 59 週年校慶，同日系上辦系友座談會及系友聚會等活動。今年以「新資訊時代的女力關鍵」為題，很榮幸邀請趙書華學姐（創為精密材料股份有限公司創辦人）、逄愛君學姐（台大資工系教授）、黃美月學姐（阿奇八八董事長）、翁子婷等學姐（Tripresso 資料工程師/PyLadies Hosts）與會座談。
Integrating Poly-Silicon and InGaZnO Thin-Film Transistors for CMOS Inverters
(2017-09-01)
Chen, ChangDong
;
Yang, Bo-Ru
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Liu, Chuan
;
Zhou, Xing-Yu
;
Hsu, Yuan-Jun
The applications of a-InGaZnO thin-film transistors (TFTs) to logic circuits have been limited owing to the intrinsic n-channel operation. In this paper, we demonstrated a hybrid inverter constructed by p-channel low-temperature poly-silicon (LTPS) TFTs and n-channel amorphous-indium-gallium-zinc-oxide (a-IGZO) TFTs. Hydrogenated LTPS TFTs and a-IGZO TFTs have been successfully fabricated on the same panel, followed by a rapid thermal annealing treatment to remove the hydrogens in the a-IGZO TFTs. The resulted hybrid inverter exhibits large noise margin closed to V-DD/2 and a high voltage gain as 68.3. Due to the complementary configurations in the static state, the inverter shows small current and thus consumes low power in hundreds of picowatts. As all the fabrication processes are compatible with conventional techniques, the reported results may open new opportunities in circuit design and applications for oxide TFTs.
System-Level ESD Protection for Automotive Electronics by Co-Design of TVS and CAN Transceiver Chips
(2017-09-01)
Chuang, Che-Hao
;
Ker, Ming-Dou
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper proposed a co-packaged methodology using transient voltage suppressor (TVS) chips and a controller area network (CAN) bus transceiver to ensure IEC 61000-4-2 system-level ESD protection. The design methodology is verified in a high-voltage silicon-on-insulator process for CAN transceiver chip and an 0.8-mu m bipolar process for TVS chips. The I-V curves of the TVS and CAN transceiver chip are evaluated by the transmission line pulsing system with the pulse width of 100 ns. The breakdown voltage of the bi-directional TVS chips and CAN transceiver chip are higher than +/- 80 V compared with the +/- 70 V fault voltage tolerance requirement. The clamping voltage of the TVS device is lower than +/- 130 V to discharge ESD current before the CAN transceiver chip breakdown for effective ESD protection. The design target of parasitic inductance by bonding wires is calculated to meet the clamping voltage requirement. The CAN bus transceiver IC with TVS chips co-packaged has been evaluated to pass the IEC61000-4-2 contact +/- 15-kV stress without any hardware damages and latch-up issues.
【院系消息】
(國立交通大學資訊學院, 2017-09)
林珮雯
本刊每學期發刊一期，做為本院師生與系友、家長的溝通橋樑。每期報導本院近期研究現況，內容包括人事動態、學人來訪以及國際交流等。期能經由本刊使讀者掌握資訊學院最新動態，促進彼此互動。
Bright carbon dots as fluorescence sensing agents for bacteria and curcumin
(2017-09-01)
Baig, Mirza Muhammad Fahad
;
Chen, Yu-Chie
;
應用化學系
;
Department of Applied Chemistry
Carbon dots (C-dots) are fluorescent nanomaterials that possess good photostability and low toxicity. They have been used as sensing probes and bioimaging agents for a variety of biological species. Numerous methods are available to generate C-dots. Nevertheless, simple and straightforward synthesis methods must be explored for the synthesis of C-dots from inexpensive, natural sources. In this study, we developed a simple method to generate C-dots from inexpensive chicken egg whites through a one-step heating reaction. The size of the generated C-dots was 3.3 +/- 0.4 nm, and the quantum yield of the C-dots was as high as similar to 43%. The as-prepared C-dots can be used as multicolor labeling agents for bacteria such as Staphylococcus aureus and Escherichia coli. Furthermore, the generated C-dots can be used as Forster resonance energy transfer sensing probes for curcumin, which is an active ingredient of turmeric and medicinal pigment. The feasibility of using the C-dots as selective sensing probes to determine the amount of curcumin from complex turmeric powder and condensed turmeric tablets is also demonstrated. (C) 2017 Elsevier Inc. All rights reserved.
【系所動態】本院首創數據科學與工程研究所
(國立交通大學資訊學院, 2017-09)
曾新穆
佈局大數據及人工智慧產業本院首創數據科學與工程研究所
Cliffs versus plains: Can ROSINA/COPS and OSIRIS data of comet 67P/Churyumov-Gerasimenko in autumn 2014 constrain inhomogeneous outgassing?
(2017-09-01)
Marschall, R.
;
Mottola, S.
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Su, C. C.
;
Liao, Y.
;
Rubin, M.
Context. This paper describes the modelling of gas and dust data acquired in the period August to October 2014 from the European Space Agency's Rosetta spacecraft when it was in close proximity to the nucleus of comet 67P/Churyumov-Gerasimenko. Aims. With our 3D gas and dust comae models this work attempts to test the hypothesis that cliff activity on comet 67P/Churyumov-Gerasimenko can solely account for the local gas density data observed by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) and the dust brightnesses seen by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) in the considered time span. Methods. The model uses a previously developed shape model of the nucleus. From this, the water sublimation rates and gas temperatures at the surface are computed. The gas expansion is modelled with a 3D Direct Simulation Monte Carlo algorithm. A dust drag algorithm is then used to compute dust volume number densities in the coma, which are then converted to brightnesses using Mie theory and a line-of-sight integration. Furthermore we have studied the impact of topographic re-radiation on the models. Results. We show that gas activity from only cliff areas produces a fit to the ROSINA/COPS data that is as statistically good as a purely insolation-driven model. In contrast, pure cliff activity does not reproduce the dust brightness observed by OSIRIS and can thus be ruled out. On the other hand, gas activity from the Hapi region in addition to cliff activity produces a statistically better fit to the ROSINA/COPS data than purely insolation-driven outgassing and also fits the OSIRIS observations rather well. We found that topographic re-radiation does not contribute significantly to the sublimation behaviour of H2O but plays an important role in how the gas flux interacts with the irregular shape of the nucleus. Conclusions. We demonstrate that fits to the observations are non-unique. We can conclude however that gas and dust activity from cliffs and the Hapi region are consistent with the ROSINA/COPS and OSIRIS data sets for the considered time span and are thus a plausible solution. Models with activity from low gravitational slopes alone provide a statistically inferior solution.
【學術交流】吳毅成教授：從AlphaGo看人工智慧之關鍵技術
(國立交通大學資訊學院, 2017-09)
林珮雯
在 AlphaGo 打敗人類棋王之後，人工智慧（AI）已成為膾炙人口的科技顯學。本院邀請吳毅成教授，從AlphaGo 暢談深度學習與強化式學習等人工智慧關鍵技術，分享他個人研究領域所獲心得，當日孔祥重院士也蒞臨與會，精彩的學術對話，演講現場座無虛席。