Browsing by Issue Date, starting with "2007-04-16"

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Upstream power equalization in a gigabit passive optical network
(2007-04-16)
Yeh, Chien-Hung
;
Hsu, Dar-Zu
;
Chi, Sien
;
光電工程學系
;
Department of Photonics
We propose a technique for achieving equalized power in upstream traffic in the gigabit passive optical network (G-PON). A simple power equalizer based on a Fabry - Perot laser diode (FP-LD) is proposed and demonstrated experimentally. By the proposed scheme, the different upstream powers can be equalized. As a result, a 20 dB dynamic upstream power range from - 5 to - 25 dBm, having a 1.7 dB maximal power variation, is attained. Moreover, the performance of the proposed configuration is also discussed. (c) 2007 Optical Society of America.
主題式分類的網路購物方法及系統
(2007-04-16)
陳穎平
本發明係有關於一種主題式分類的網路購物方法及系統,使用者透過網路瀏覽器連結到網路購物系統,進入一購物或檢索性質的網站,該網站提供使用者輸入公衆人物、美術、圖書、音樂、電影、戲刻、文藝著作、漫畫、新聞等一個或一個以上之關鍵語,將所輸入之關鍵語與資料庫中比對是否有相關之產品。
低密度高韌性合金材料及其製法
(2007-04-16)
劉增豐
;
李堅瑋
一種低密度高韌性合金材料及其製法,其主要組成為以重量百分比計,大於等於23小於等於33的錳,大於等於8.1小於等於9.8的鋁,大於等於3小於等於7.8的鉻,大於等於0.6小於等於1.2的碳,大於等於0.1小於等於0.24的矽及其餘比例為鐵之合金材料。上所揭示之合金成份之合金材料製作高爾夫球頭時,不須任何熱處理及鍛造、軋延等熱作和冷作塑性加工,即可使高爾夫球頭具有極佳的延伸性、强度、吸震性及抗蝕性等特性,大幅降低目前的生產成本。
Size dependence of tetrahedral bond lengths in CdSe nanocrystals
(2007-04-16)
Wu, Pin-Jiun
;
Stetsko, Yuri P.
;
Tsuei, Ku-Ding
;
Dronyak, Roman
;
Liang, Keng S.
The structural characteristics of organically passivated CdSe nanocrystals (NCs) were investigated with x-ray diffraction and extended x-ray absorption fine structure. As the NC size decreases, the axial bond length R-(1) for an atomic tetrahedron extends but the equatorial bond length R-(2) contracts, with a similar tendency of distortion for the lattice parameters of the wurtzite structure. The authors suggest that the observed hexagonal distortion is attributed to the surface stress of the NCs related to the organic passivation effect and the relaxation of atomic positions at the stacking fault interface. (c) 2007 American Institute of Physics.
White light generation under violet-blue excitation from tunable green-to-red emitting Ca2MgSi2O7 : Eu,Mn through energy transfer
(2007-04-16)
Chang, Chun-Kuei
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
Yellowish green-to-orange red emission can be generated by energy transfer from Eu2+ to Mn2+ in the Ca2MgSi2O7 host matrix. Eu2+-doped Ca2MgSi2O7 shows a broad green emission band centering at 528 nm and Mn2+-doped Ca2MgSi2O7 exhibits a red emission at around 602 nm. The authors have demonstrated that the mechanism of energy transfer from Eu2+ to Mn2+ in Ca2MgSi2O7:Eu,Mn phosphor is a resonant type via a dipole-quadrupole mechanism. They have also shown that the white light with varied hue, depending on contents of Mn2+, is generated by combination of predesigned emission wavelength-tunable Ca2MgSi2O7:Eu,Mn phosphors and violet-blue light source. (c) 2007 American Institute of Physics.
Nanogap formation by palladium hydrogenation for surface conduction electron emitters fabrication
(2007-04-16)
Tsai, Chih-Hao
;
Pan, Fu-Ming
;
Chen, Kuan-Jung
;
Wei, Cheng-Yang
;
Liu, Mei
Nanometer-scale gaps in Pd strips are obtained by hydrogen absorption under high pressure treatment. The resulting lattice constant increase due to the Pd phase transformation after hydrogen uptake results in a large compressive stress on the thin Pd films. Under proper geometric arrangement of the Pd electrode within a surface conduction electron (SCE) emitter structure, a single nanogap per SCE device is obtained. A turn-on voltage of 41 V is observed for emitters with a 25 nm gap. (c) 2007 American Institute of Physics.
水中溶解矽酸的移除
(2007-04-16)
黃志彬
;
林欣慧
本發明係關於一種利用鋁或鐵之氫氧化物在水中溶解態與固態的交替改變(以下簡稱相變),以移除水中溶解矽酸之方法。主要以鋁或鐵之水合固態相(即Al(OH)3或Fe(OH)3,以下簡稱膠羽),在pH偏鹼之吸附反應槽對進流之矽酸進行吸附,經過固液分離裝置後,將高濃度之膠羽懸浮液濃縮迴流至反應槽,但迴流至反應槽前需經pH調整槽將懸浮液之pH再調整至極酸性或極鹼性範圍,以令膠羽溶解。本發明可同時移除水中溶解矽酸及非溶解性二氧化矽。進流原水即便含有數十ppm的高濃度溶解矽酸,亦可降至一滿意程度(例如:0.5–5.0 ppm)甚至更低(視系統吸附劑總濃度而定),且系統中之膠羽可不斷循環使用。
Reflective second harmonic generation from ZnO thin films: A study on the Zn-O bonding
(2007-04-16)
Lo, Kuang Yao
;
Huang, Yi Jen
;
Huang, Jung Y.
;
Feng, Zhe Chuan
;
光電工程學系
The structures of the Zn-O bonding in ZnO (0002) thin films prepared by metal organic chemical vapor deposition have been studied by reflective second harmonic generation (RSHG). The polar Zn-O bond on the top layer is not canceled out and presents 3 mm symmetrical structures on the well-grown ZnO (0002) surface. The average polar strength of the Zn-O bond is correlated with the quality of the ZnO (0002) thin film. The mirror symmetry is caused by the nonvanished polar of twin boundary due to the mismatch between the ZnO film and sapphire substrate and analyzed using s-polarized RSHG with s-polarized fundamental light irradiation. These results demonstrate that the Zn-O heteropolar bonds on the smooth ZnO surface contribute to the SHG intensity. (c) 2007 American Institute of Physics.
Dichromatic InGaN-based white light emitting diodes by using laser lift-off and wafer-bonding schemes
(2007-04-16)
Lee, Y. J.
;
Lin, P. C.
;
Lu, T. C.
;
Kuo, H. C.
;
Wang, S. C.
An InGaN-based dual-wavelength blue/green (470 nm/550 nm) light emitting diode (LED) with three terminal operations has been designed and fabricated by using sapphire laser lift-off and wafer-bonding schemes. The device is equivalent to a parallel connection of blue and green LEDs; thus the effective electrical resistance of the device could be reduced. The luminous efficiency is 40 lm/W at 20 mA, accompanied by a broad electroluminescence emission with a combination of blue and green colors. This monolithically integrated dichromatic lighting structure has great potential in the application of the solid-state lighting. (c) 2007 American Institute of Physics.
Extended VIKOR method in comparison with outranking methods
(2007-04-16)
Opricovic, Serafim
;
Tzeng, Gwo-Hshiung
;
科技管理研究所
;
Institute of Management of Technology
The VIKOR method was developed to solve MCDM problems with conflicting and noncommensurable (different units) criteria, assuming that compromising is acceptable for conflict resolution, the decision maker wants a solution that is the closest to the ideal, and the alternatives are evaluated according to all established criteria. This method focuses on ranking and selecting from a set of alternatives in the presence of conflicting criteria, and on proposing compromise solution (one or more). The VIKOR method is extended with a stability analysis determining the weight stability intervals and with trade-offs analysis. The extended VIKOR method is compared with three multicriteria decision making methods: TOPSIS, PROMETHEE, and ELECTRE. A numerical example illustrates an application of the VIKOR method, and the results by all four considered methods are compared. (c) 2006 Elsevier B.V. All rights reserved.
Direct and in vitro observation of growth hormone receptor molecules in A549 human lung epithelial cells by nanodiamond labeling
(2007-04-16)
Cheng, C.-Y.
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Perevedentseva, E.
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Tu, J.-S.
;
Chung, P.-H.
;
Cheng, C.-L.
This letter presents direct observation of growth hormone receptor in one single cancer cell using nanodiamond-growth hormone complex as a specific probe. The interaction of surface growth hormone receptor of A549 human lung epithelial cells with growth hormone was observed using nanodiamond's unique spectroscopic signal via confocal Raman mapping. The growth hormone molecules were covalent conjugated to 100 nm diameter carboxylated nanodiamonds, which can be recognized specifically by the growth hormone receptors of A549 cell. The Raman spectroscopic signal of diamond provides direct and in vitro observation of growth hormone receptors in physiology condition in a single cell level. (C) 2007 American Institute of Physics.
Geodetic and geophysical results from a Taiwan airborne gravity survey: Data reduction and accuracy assessment
(2007-04-17)
Hwang, Cheinway
;
Hsiao, Yu-Shen
;
Shih, Hsuan-Chang
;
Yang, Ming
;
Chen, Kwo-Hwa
[ 1] An airborne gravity survey was conducted over Taiwan using a LaCoste and Romberg (LCR) System II air-sea gravimeter with gravity and global positioning system (GPS) data sampled at 1 Hz. The aircraft trajectories were determined using a GPS network kinematic adjustment relative to eight GPS tracking stations. Long-wavelength errors in position are reduced when doing numerical differentiations for velocity and acceleration. A procedure for computing resolvable wavelength of error-free airborne gravimetry is derived. The accuracy requirements of position, velocity, and accelerations for a 1-mgal accuracy in gravity anomaly are derived. GPS will fulfill these requirements except for vertical acceleration. An iterative Gaussian filter is used to reduce errors in vertical acceleration. A compromising filter width for noise reduction and gravity detail is 150 s. The airborne gravity anomalies are compared with surface values, and large differences are found over high mountains where the gravity field is rough and surface data density is low. The root mean square (RMS) crossover differences before and after a bias-only adjustment are 4.92 and 2.88 mgal, the latter corresponding to a 2-mgal standard error in gravity anomaly. Repeatability analyses at two survey lines suggest that GPS is the dominating factor affecting the repeatability. Fourier transform and least-squares collocation are used for downward continuation, and the latter produces a better result. Two geoid models are computed, one using airborne and surface gravity data and the other using surface data only, and the former yields a better agreement with the GPS-derived geoidal heights. Bouguer anomalies derived from airborne gravity by a rigorous numerical integration reveal important tectonic features.
夜這個黑道
(2007-04-18)
管管
Low-density high-toughness alloy and the fabrication method thereof
(2007-04-19)
Liu, Tzeng-Feng
;
Lee, Jian-Wei
The present invention discloses a low-density high-toughness alloy and the fabrication method thereof. The alloy of the present invention consists essentially of: by weight percent, equal to or greater than 23% but lower than or equal to 33% manganese, equal to or greater than 8.1% but lower than or equal to 9.8% aluminum, equal to or greater than 3% but lower than or equal to 7.8% chromium, equal to or greater than 0.6% but lower than or equal to 1.2% carbon, equal to or greater than 0.1% but lower than or equal to 0.24% silicon and the balance of iron. The golf-club head made from the abovementioned alloy can obtain superior elongation, strength, damping capacity, and corrosion resistance even without any heat treatment, or any hot/cold working, such as forging and rolling; therefore, the fabrication cost thereof can be obviously reduced.
Passively Q-switched Yb3+: YCa4O(BO3)(3) laser with InGaAs quantum wells as saturable absorbers
(2007-04-20)
Liang, H. C.
;
Huang, J. Y.
;
Su, K. W.
;
Lai, H. C.
;
Chen, Y. F.
A diode-pumped Yb:YCOB laser at 1086 nm is passively Q switched by using InGaAs quantum wells as saturable absorbers and utilizing the Bragg mirror structure as an output coupler. With an absorbed pump power of 9.2 W the laser produces pulses of 100 ms duration with average pulse energy of as much as 165 mu J at a pulse repetition rate of 7 kHz. (c) 2007 Optical Society of America.
Interplay of anisotropy and disorder in the doping-dependent melting and glass transitions of vortices in Bi2Sr2CaCu2O8+delta
(2007-04-20)
Beidenkopf, H.
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Verdene, T.
;
Myasoedov, Y.
;
Shtrikman, H.
;
Zeldov, E.
We study the oxygen doping dependence of the equilibrium first-order melting and second-order glass transitions of vortices in Bi2Sr2CaCu2O8+delta. Doping affects both anisotropy and disorder. Anisotropy scaling is shown to collapse the melting lines only where thermal fluctuations are dominant. Yet, in the region where disorder breaks that scaling, the glass lines are still collapsed. A quantitative fit to melting and replica symmetry-breaking lines of a 2D Ginzburg-Landau model further reveals that disorder amplitude weakens with doping, but to a lesser degree than thermal fluctuations, enhancing the relative role of disorder.
Crystal structure of Helicobacter pylori formamidase AmiF reveals a cysteine-glutamate-lysine catalytic triad
(2007-04-20)
Hung, Chiu-Lien
;
Liu, Jia-Hsin
;
Chiu, Wei-Chun
;
Huang, Shao-Wei
;
Hwang, Jenn-Kang
Helicobacter pylori AmiF formamidase that hydrolyzes formamide to produce formic acid and ammonia belongs to a member of the nitrilase superfamily. The crystal structure of AmiF was solved to 1.75 angstrom resolution using single-wavelength anomalous dispersion methods. The structure consists of a homohexamer related by 3-fold symmetry in which each subunit has an alpha-beta-beta-alpha four-layer architecture characteristic of the nitrilase superfamily. One exterior alpha layer faces the solvent, whereas the other one associates with that of the neighbor subunit, forming a tight alpha-beta-beta-alpha-alpha-beta-beta-alpha dimer. The apo and liganded crystal structures of an inactive mutant C166S were also determined to 2.50 and 2.30 angstrom, respectively. These structures reveal a small formamide-binding pocket that includes Cys(166), Glu(60), and Lys(133) catalytic residues, in which Cys166 acts as a nucleophile. Analysis of the liganded AmiF and N-carbamoyl D-amino acid amidohydrolase binding pockets reveals a common Cys-Glu-Lys triad, another conserved glutamate, and different subsets of ligand-binding residues. Molecular dynamic simulations show that the conserved triad has minimal fluctuations, catalyzing the hydrolysis of a specific nitrile or amide in the nitrilase superfamily efficiently.
攝影機參數校正方法
(2007-04-21)
陳冠文
;
洪一平
本發明為一種攝影機參數校正方法，主要是基於受到地心引力影響的運動物體對攝影機或相機進行校正。此方法首先使運動物體由於受到的地心引力影響而構成拋物線之運動軌跡、使攝影機以特定的快門速度，對在運動路徑中運動的運動物體連續拍攝，而獲得複數個特定拍攝時間和在影像座標上的特定xy位置的校正影像、以及依據透視投影幾何方程式，而基於影像座標的位置和拍攝時間獲得用來求出攝影機的內部參數和外部參數之平面投影轉換矩陣。
低密度高韌性合金材料及其製法
(2007-04-21)
劉增豐
;
李堅瑋
一種低密度高韌性合金材料及其製法，其主要組成為以重量百分比計，大於等於23小於等於33的錳，大於等於8.1小於等於9.8的鋁，大於等於3小於等於7.8的鉻，大於等於0.6小於等於1.2的碳，大於等於0.1小於等於0.24的矽及其餘比例為鐵之合金材料。上所揭示之合金成份之合金材料製作高爾夫球頭時，不須任何熱處理及鍛造、軋延等熱作和冷作塑性加工，即可使高爾夫球頭具有極佳的延伸性、強度、吸震性及抗蝕性等特性，大幅降低目前的生產成本。
雷射微加工處理全光纖型元件之製作方法
(2007-04-21)
祁甡
;
陳南光
本案係指一種雷射微加工處理全光纖型元件之製作方法，係直接對光纖之部分光殼施以雷射切削去除，使得光纖內的消逝場(evanescent field)能夠裸露出來，切削的深度可藉由量測雷射光干涉條紋間距的方法得知；雷射切削形成的消逝場之作用長度則可透過改變光纖曲率半徑控制。將側削後之光纖彼此靠合，使其光消逝場能夠發生耦合後予以加熱熔合或施以熔燒拉錐(fuse-tapering)，即可用來製作光纖耦合器、光塞取多工器(add/drop multiplexer)、光纖窄波道多工/解多工器及光纖光柵等光纖元件。