Browsing by Issue Date, starting with "2011-07-05"

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Surface-emitting laser device
(2011-07-05)
Chen Shih-Wei
;
Lu Tien-Chang
;
Kuo Hao-Chung
;
Wang Shing-Chung
A surface-emitting laser device includes: a substrate; a low refractive index layer with a refractive index nL and disposed on the substrate; a light emitting layered structure with a refractive index nH, where nH>nL, the light emitting layered structure being formed on the low refractive index layer and having first and second semiconductor layers and a multi-quantum well (MQW) disposed between the first and second semiconductor layers and capable of generating photons having a wavelength λ0; and a two-dimensional photonic crystal (2DPC) formed in the light emitting layered structure and having optical nanostructures arranged into a periodic pattern with a lattice constant a. The nanostructures extend from the first semiconductor layer through the MQW. The 2DPC has a normalized frequency, which is defined as a/λ0, ranging from 0.25 to 0.70.
交大e-News第097期
(2011-07-05)
Secretariat
;
國立交通大學秘書室
Organic-semiconductor-based infrared receiving device
(2011-07-05)
Meng Hsin-Fei
;
Horng Sheng-Fu
;
Yang Chia-Ming
An organic-semiconductor-based infrared receiving device comprises an electrode layer having a positive layer and a negative layer to form an electric field, and a transport layer located between the positive and negative layers and having a first and a second predetermined material combined in a predetermined ratio. The energy of infrared light from a light source is received at an interface between the first and second materials. The thickness of the transport layer can be increased to enhance the light absorbance in the infrared light range to form electron-hole pairs, which are then parted to form a plurality of electrons and holes driven by the electric field to move to the negative layer and the positive layer, respectively, so that a predetermined photocurrent is generated.
Exploring the selective constraint on the sizes of insertions and deletions in 5 ' untranslated regions in mammals
(2011-07-05)
Chen, Chun-Hsi
;
Liao, Ben-Yang
;
Chen, Feng-Chi
;
生物科技學系
;
Department of Biological Science and Technology
Background: Small insertions and deletions ("indels" with size <= 100 bp) whose lengths are not multiples of three (non-3n) are strongly constrained and depleted in protein-coding sequences. Such a constraint has never been reported in noncoding genomic regions. In 5' untranslated regions (5' UTRs) in mammalian genomes, upstream start codons (uAUGs) and upstream open reading frames (uORFs) can regulate protein translation. The presence of non-3n indels in uORFs can potentially disrupt the functions of these regulatory elements. We thus hypothesize that natural selection disfavors non-3n indels in 5' UTRs when these regulatory elements are present. Results: We design the Indel Selection Index to measure the selective constraint on non-3n indels in 5' UTRs. The index controls for the genomic compositions of the analyzed 5' UTRs and measures the probability of non-3n indel depletion downstream of uAUGs. By comparing the experimentally supported transcripts of human-mouse orthologous genes, we demonstrate that non-3n indels downstream of two types of uAUGs (alternative translation initiation sites and the uAUGs of coding sequence-overlapping uORFs) are underrepresented. The results hold well regardless of differences in alignment tool, gene structures between human and mouse, or the criteria in selecting alternatively spliced isoforms used for the analysis. Conclusions: To our knowledge, this is the first study to demonstrate selective constraints on non-3n indels in 5' UTRs. Such constraints may be associated with the regulatory functions of uAUGs/uORFs in translational regulation or the generation of protein isoforms. Our study thus brings a new perspective to the evolution of 5' UTRs in mammals.
Calculation of spontaneous emission from a V-type three-level atom in photonic crystals using fractional calculus
(2011-07-05)
Huang, Chih-Hsien
;
Wu, Jing-Nuo
;
Li, Yen-Yin
;
Cheng, Szu-Cheng
;
Hsieh, Wen-Feng
Fractional time derivative, an abstract mathematical operator of fractional calculus, is used to describe the real optical system of a V-type three-level atom embedded in a photonic crystal. A fractional kinetic equation governing the dynamics of the spontaneous emission from this optical system is obtained as a fractional Langevin equation. Solving this fractional kinetic equation by fractional calculus leads to the analytical solutions expressed in terms of fractional exponential functions. The accuracy of the obtained solutions is verified through reducing the system into the special cases whose results are consistent with the experimental observation. With accurate physical results and avoiding the complex integration for solving this optical system, we propose fractional calculus with fractional time derivative as a better mathematical method to study spontaneous emission dynamics from the optical system with non-Markovian dynamics.
Process for treating nitrogenous wastewater with simultaneous autotrophic denitrification, hetertrophic denitrification and COD removal
(2011-07-05)
Lee Der-Ming
;
Chiang Ming-Kuei
;
Chen Chin-Te
;
Sung Keng-Chuan
;
Lin Jih-Gaw
A process for treating nitrogenous wastewater contains an autotrophic denitrification reaction, a heterotrophic denitrification reaction and a COD removal reaction simultaneously and mixedly taking place in a single reactor. The nitrification reaction is caused by nitrifying bacteria, in which ammonium is oxidized into nitrite. The autotrophic denitrification reaction is caused by autotrophic denitrifying bacteria, in which ammonium used as electron donor and nitrite used as electron acceptor are converted into nitrogen gas and nitrate. The heterotrophic denitrification reaction is caused by heterotrophic denitrifying bacteria, in which nitrate and COD are consumed. It is not necessary to build two separate reactors for aerobic nitrification and anaerobic denitrification, thereby effectively reducing the fabrication and operation cost.
Fiber grating sensor
(2011-07-05)
Huang An-Bin
;
Kao Sheng-Chiang
A fiber grating sensor including an elastic circular plate and one or two FBG'ss attached to the bottom surface of the elastic circular plate. Two ends of the FBG are connected to an optic fiber for signal transmission. The fiber grating sensor readouts are independent of temperature variation. The fiber grating sensor mechanism according to the present invention may be applied in a variety of sensors such as gauge pressure transducer, differential pressure transducer, load cell and displacement transducer with a distributive design, and for various purposes.
High load driving device
(2011-07-05)
Chuang Ching-Te
;
Lu Chien-Yu
A high load driving device is disclosed. The driving device comprises an inverter receiving a digital voltage. The inverter reverses the digital voltage, and then sends out it. The output terminal of the inverter is coupled to a capacitor, a first P-type field-effect transistor (FET), a second P-type FET, a first N-type FET, and a third N-type FET. A push-up circuit is composed of these transistors and a second N-type FET and coupled to a P-type push-up FET. A load is coupled to a high voltage through the P-type push-up FET. When the digital voltage rises from a low level to a high level, the push-up circuit utilizes the original voltage drop of the capacitor to control the P-type push-up FET, whereby the gate voltage of the P-type push-up FET is at a low stabilization voltage that is lower than the ground potential. Then, the load is driven rapidly.
最佳空間-時間-頻率區塊碼之搜尋方法及其多輸入多輸出之多頻帶超寬頻系統
(2011-07-11)
王蒞君
;
劉維正
一種最佳空間－時間－頻率(space－time－frequency，STF)區塊碼之搜尋方法能夠以較少的運算量，有系統地搜尋出最佳之空間－時間－頻率區塊碼。同時亦揭露一種多輸入多輸出之多頻帶超寬頻系統，其以上述之最佳STF區塊碼進行編碼，以使位元錯誤率達到最小。
16-Hydroxycleroda-3,13-dien-15,16-olide deregulates PI3K and Aurora B activities that involve in cancer cell apoptosis
(2011-07-11)
Lin, Yi-Hsiung
;
Lee, Chien-Chih
;
Chan, Wen-Li
;
Chang, Wen-Hsin
;
Wu, Yang-Chang
The PI3K-AKT pathway and Aurora kinase play essential roles in such cellular processes as cell survival, angiogenesis, and differentiation, and are usually expressed at maximum levels during cancer cell proliferation. The present study investigated the effect of the natural compound, 16-hydroxycleroda-3,13-dien-15,16-olide (PL3), on regulating the PI3K-AKT pathway and Aurora B, which led to cancer cell apoptosis. PL3 acts as a PI3K inhibitor by influencing cell survival, signaling transduction, and cell cycle progression. It was observed that PL3 targeted and induced dephosphorylation of the PI3K pathway, degradation of Aurora B and mitotic-related gene expressions, and sequentially shut down the cell cycle. This eventually resulted in cell death. As Aurora B was downregulated, spindle dysfunction and destruction of the G(2)/M phase checkpoint resulted in DNA-damaged cells undergoing apoptosis. Moreover. PL3 also resensitized T31 5I-mutated Bcr-ABL(+) BA/F3 cells to improve the cytotoxicity of Imatinib in Imatinib-resistant cell line. Taken together, PL3 can perturb the PI3K-AKT pathway and Aurora B resulting in gene silencing and cell cycle disturbance. It was demonstrated that PL3 acted like a novel small-molecule PI3K modulator, thereby potentially contributing to cancer chemotherapy and combination medication. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
無線網路中執行換手程序的裝置與方法
(2011-07-11)
林一平
;
許世芬
一種無線網路中執行換手程序的裝置與方法。此裝置包含一處理機執行一識別碼檢查機制，當無線網路用戶欲從一來源存取點移動至一目的地存取點時，無線網路用戶傳送一認證要求訊息至目的地存取點，識別碼檢查機制將認證要求訊息內的一R0金鑰持有者識別碼向此目的地存取點的一R0KH表查詢，並決定出正確換手程序的一設定參數，依此讓該無線網路用戶執行換手程序。目的地存取點之R0KH表是由在此目的地存取點網域範圍下可被其存取之所有R0金鑰持有者的識別碼來組成。
Optical properties of self assembled GaN polarity inversion domain boundary
(2011-07-11)
Liu, M. -C.
;
Cheng, Y. -J.
;
Chang, J. -R.
;
Hsu, S. -C.
;
Chang, C. -Y.
We report the fabrication of GaN lateral polarity inversion heterostructure with self assembled crystalline inversion domain boundaries (IDBs). The sample was fabricated by two step molecular-beam epitaxy (MBE) with microlithography patterning in between to define IDBs. Despite the use of circular pattern, hexagonal crystalline IDBs were self assembled from the circular pattern during the second MBE growth. Both cathodoluminescent (CL) and photoluminescent (PL) measurements show a significant enhanced emission at IDBs and in particular at hexagonal corners. The ability to fabricate self assembled crystalline IDBs and its enhanced emission property can be useful in optoelectronic applications. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3610449]
Investigating the degradation behavior caused by charge trapping effect under DC and AC gate-bias stress for InGaZnO thin film transistor
(2011-07-11)
Chen, Te-Chih
;
Chang, Ting-Chang
;
Hsieh, Tien-Yu
;
Lu, Wei-Siang
;
Jian, Fu-Yen
This letter investigates the degradation mechanism of amorphous indium-gallium-zinc oxide thin-film transistors under gate-bias stress. The larger V(t) shift under positive AC gate-bias stress when compared to DC operation indicates that an extra electron trapping mechanism occurs during rising/falling time during the AC pulse period. In contrast, the degradation behavior under illuminated negative gate-bias stress exhibits the opposite degradation tendency. Since electron and hole trapping are the dominant degradation mechanisms under positive and illuminated negative gate-bias stress, respectively, the different degradation tendencies under AC/DC operation can be attributed to the different trapping efficiency of electrons and holes. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3609873]
Tone-interleaved coded modulation scheme for MIMO OFDM communication
(2011-07-12)
Wu Wen-Rong
;
Shen Shih-Chi
A MIMO OFDM system for TICM includes a tone-level interleaver at the transmitter using a block of NT symbols as its basic unit. This results in different decoding architectures at the receiver. The main advantage of TICM is to merge soft-bit demapping into the Viterbi algorithm. Taking advantage of the trellis structure inherent in the Viterbi algorithm, TICM can have lower computational complexity and potentially better performance than BICM with the LSD detector and the vector demapper. Although the tone-level interleaving may not have spatial diversity gain, the performance is not affected in 802.11n environments.
Light emitter device
(2011-07-12)
Chang Chun-Yen
;
Yang Tsung Hsi
A light emitting device (LED) structure formed on a Group IV-based semiconductor substrate is provided. The LED structure includes a Group IV-based substrate, an AlN nucleation layer formed on the Group IV-based substrate, a GaN epitaxial layer formed on the AlN nucleation layer, a distributed Bragg reflector (DBR) multi-layer structure formed on the epitaxial layer, and an LED active layer formed on the DBR multi-layer structure.
Digital fast-locking frequency synthesizer
(2011-07-12)
Chen Wei-Zen
;
Yang Song-Yu
A digital PLL frequency synthesizer characterized by fast-locking and low-jitters is presented. The PLL comprises a phase detector, a controllable oscillator, a loop filter having an automatically-adjusted loop gain, a feedback phase integration circuit, and a reference phase integration circuit. Fast-locking is achieved by dynamically adjusting forward-path gain and integral-path gain according to the output of the phase detector and the output of the integral-path during phase tracking. A skew-compensated counter circuit is proposed, which incorporates an asynchronous counter, a data register and a sample phase generator and features high-speed and low-power operation.
Suspended nanochannel transistor structure and method for fabricating the same
(2011-07-12)
Lin Horng-Chih
;
Su Chun-Jung
;
Hsu Hsing-Hui
;
Li Guan-Jang
The present invention discloses a suspended nanochannel transistor structure and a method for fabricating the same. The transistor structure of the present invention comprises a substrate; a side gate formed on the substrate; a dielectric layer covering the substrate and the side gate; a suspended nanochannel formed beside the lateral of the side gate with an air gap existing between the suspended nanochannel and the dielectric layer; a source and a drain formed over the dielectric layer and respectively arranged at two ends of the suspended nanochannel. The electrostatic force of the side gate attracts or repels the suspended nanochannel and thus fast varies the equivalent thickness of the side-gate dielectric layer. Thereby, the on/off state of the element is rapidly switched, or the initial voltage of the channel is altered.
METHOD FOR FABRICATING A RESISTOR FOR A RESISTANCE RANDOM ACCESS MEMORY
(2011-07-14)
TSENG Tseung-Yuen
;
Wang Sheng-Yu
;
Tsai Chen-Han
A method for fabricating a resistor for a resistance random access memory (RRAM) includes: (a) forming a first electrode over a substrate; (b) forming a variable resistance layer of zirconium oxide on the first electrode under a working temperature, which ranges from 175° C. to 225° C.; and (c) forming a second electrode of Ti on the variable resistance layer.
Planar band-notched ultra-wideband antenna with square-looped and end-coupled resonator
(2011-07-14)
Wu, S-J.
;
Tarng, J-H.
;
電信工程研究所
;
Institute of Communications Engineering
A square-looped and an end-coupled resonator used in a planar ultra-wideband (UWB) antenna to achieve band-notched performance are presented here. To obtain notched performance in the wireless local area network band, both the square-looped and end-coupled resonator are designed and placed in a fork-shaped UWB antenna centre. The characteristics and schematic equivalent circuit of each resonator are also discussed. Parametric studies of a fork-shaped antenna with square-looped resonator are given as an example to explore the operating mechanism. Accordingly, the band-notched antenna can effectively select target bands by adjusting different resonator structures. The proposed antenna features flat gain-frequency response and group delay as well as 10-25 dB gain suppression in the notched band.
Detection of autoantibodies against Rabphilin-3A-like protein as a potential biomarker in patient's sera of colorectal cancer
(2011-07-15)
Chen, Jinn-Shiun
;
Kuo, Yung-Bin
;
Chou, Yeh-Pin
;
Chan, Chung-Chuan
;
Fan, Chung-Wei
Background: Rabphilin-3A-like (RPH3AL) protein functions in the regulation of hormone exocytosis, and mutations in the RPHA3L gene have been associated with tumorigenesis in colorectal cancer (CRC). We evaluated the potential use of anti-RPH3AL autoantibodies as a marker for CRC detection. Methods: Sera from 84 patients with CRC and 63 healthy controls were analysed for the presence of RPH3AL autoantibodies with a Western blotting assay. Results: The frequencies of RPH3AL autoantibodies in the early stage, advanced stage and all CRC patients were 64.7%, 78.0% and 72.6%, respectively. These values are significantly higher than the frequency of RPH3AL autoantibodies in healthy controls (15.9%, P<0.001). Although the presence of RPH3AL autoantibodies did not correlate with clinical parameters, RPH3AL autoantibodies were found in 69.4% (34/49) of CRC patients who were negative for carcinoembryonic antigen. The value of the area under the receiver operating characteristic curve of RPH3AL autoantibody was 0.84, which suggests that screening for these autoantibodies could potentially be used for CRC diagnosis. Conclusion: Circulating RPH3AL autoantibodies are prevalent in patients with CRC, and detection of these autoantibodies might provide a novel non-invasive approach for CRC diagnosis. (C) 2011 Elsevier B.V. All rights reserved.