Browsing by Issue Date, starting with "2006-08-18"

Now showing 1 - 20 of 62867

Spin cloud induced around an elastic scatterer by the intrinsic spin Hall effect
(2006-08-18)
Mal'shukov, A. G.
;
Chu, C. S.
;
電子物理學系
;
Department of Electrophysics
Similar to the Landauer electric dipole created around an impurity by the electric current, a spin polarized cloud of electrons can be induced by the intrinsic spin Hall effect near a spin independent elastic scatterer. It is shown that in the ballistic range around the impurity, such a cloud appears in the case of Rashba spin-orbit interaction, even though the bulk spin Hall current is absent.
Defining equations of modular curves
(2006-08-20)
Yang, Yifan
;
應用數學系
;
Department of Applied Mathematics
We obtain defining equations of modular curves X-0(N), X-1(N), and X(N) by explicitly constructing modular functions using generalized Dedekind eta functions. As applications, we describe a method of obtaining a basis for the space of cusp forms of weight 2 on a congruence subgroup. We also use our model of X-0(37) to find explicit modular parameterization of rational elliptic curves of conductor 37. (C) 2005 Elsevier Inc. All rights reserved.
Absorption cross sections of NH3, NH2D, NHD2, and ND3 in the spectral range 140-220 nm and implications for planetary isotopic fractionation
(2006-08-20)
Cheng, Bing-Ming
;
Lu, Hsiao-Chi
;
Chen, Hong-Kai
;
Bahou, Mohammed
;
Lee, Yuan-Pern
Cross sections for photoabsorption of NH3, NH2D, NHD2, and ND3 in the spectral region 140-220 nm were determined at similar to 298 K using synchrotron radiation. Absorption spectra of NH2D and NHD2 were deduced from spectra of mixtures of NH3 and ND3, of which the equilibrium concentrations for all four isotopologues obey statistical distributions. Cross sections of NH2D, NHD2, and ND3 are new. Oscillator strengths, an integration of absorption cross sections over the spectral lines, for both A X and B X systems of NH3 agree satisfactorily with previous reports; values for NH2D, NHD2, and ND3 agree with quantum chemical predictions. The photolysis of NH3 provides a major source of reactive hydrogen in the lower stratosphere and upper troposphere of giant planets such as Jupiter. Incorporating the measured photoabsorption cross sections of NH3 and NH2D into the Caltech/JPL photochemical diffusive model for the atmosphere of Jupiter, we find that the photolysis efficiency of NH2D is lower than that of NH3 by as much as 30%. The D/H ratio in NH2D/NH3 for tracing the microphysics in the troposphere of Jupiter is also discussed.
Nonlinear dynamics in thin-slice Nd : YAG ceramic lasers: Coupled local-mode laser model
(2006-08-21)
Otsuka, Kenju
;
Narita, Tatsuro
;
Miyasaka, Yoshihiko
;
Lin, Chi-Ching
;
Ko, Jing-Yuan
The authors propose a coupled spatially distributed local-mode laser model for understanding self-induced high-speed modulations in Nd:YAG ceramic lasers with laser-diode end pumping, which critically depend on pump positions. In addition to complicated high-speed modulations, quasiperiodic and chaotic relaxation oscillations have been demonstrated experimentally and reproduced by numerical simulation of the model of coupled local-mode lasers. Q-switching-like periodic spiking pulsations have been also observed and reproduced numerically by assuming saturable absorber type of inclusions in grain boundaries.
Effects of strain on the electronic structures and T-C's of the La0.67Ca0.33MnO3 and La0.8Ba0.2MnO3 thin films deposited on SrTiO3
(2006-08-21)
Chou, Hsiung
;
Tsai, M. -H.
;
Yuan, F. P.
;
Hsu, S. K.
;
Wu, C. B.
The strain effects on the electronic structures of La0.67Ca0.33MnO3 (LCMO) and La0.8Ba0.2MnO3 (LBMO) thin films have been studied by O K-edge x-ray absorption near edge structure (XANES) spectroscopy. For LCMO, the first-principles calculations reveal that the features in the XANES spectra are associated with hybridized states between O 2p and Mn minority-spin 3d t(2g) and e(g), La 5d/Ca 3d, and Mn 4s/Ca 4p states. An analysis of these features shows that the tensile strain decreases substantially La-O and Ca-O hybridization and T-C for LCMO. For LBMO, the small compressive strain enhances slightly La-O and Ba-O hybridization and T-C. (c) 2006 American Institute of Physics.
Thermal stability of Ti/Pt/Cu Schottky contact on InAlAs layer
(2006-08-21)
Lien, Yi-Chung
;
Chang, Edward Yi
;
Chen, Szu-Hung
;
Chu, Li-Hsin
;
Chen, Po-Chou
Electrical characteristics and thermal stability of the Ti/Pt/Cu Schottky contact on InAlAs were investigated. The Ti/Pt/Cu Schottky contact had comparable electrical properties compared to the conventional Ti/Pt/Au contact after annealing. As judged from the material analysis, the Ti/Pt/Cu on InAlAs after 350 degrees C annealing showed no diffusion sign into the InAlAs. After 400 degrees C annealing, the interfacial mixing of Cu and the underlying layers occurred and resulted in the formation of Cu4Ti. The results show that Ti/Pt/Cu Schottky contact using platinum as the diffusion barrier is very stable up to 350 degrees C annealing and can be used for InAlAs/InGaAs high-electron mobility transistors and monolithic microwave integrated circuits. (c) 2006 American Institute of Physics.
具有防止源汲極區摻雜離子在接面區外擴散的電晶體結構及其製作方法
(2006-08-21)
羅廣禮
;
楊宗
;
張翼
;
張俊彥
本發明係揭露一種具有防止源汲極區摻雜離子在接面區外擴散的電晶體結構及其製作方法，其係於半導體基底上形成材質為具有摻雜離子的含碳-矽化鍺(SiGe：C)嵌入式源汲極，利用碳能夠抑制摻雜離子擴散的特性，來形成兼具低接觸電阻與能抑制摻雜離子擴散的源汲極區，進而提高元件的可靠度。
磁光式之近場光學光儲存元件
(2006-08-21)
徐文祥
;
謝漢萍
;
孫翊庭
本發明係提供一種磁光式之近場光學光儲存元件，係先利用犧牲層製作空氣軸承結構；再定義一初始小孔，並以電鍍法縮小該孔至奈米等級，再以兩次之厚膜光阻層配合兩次電鍍製程，製作高深寬比之金屬線圈結構與金屬內連線；可有效利用面積與降低電阻，最後利用微影製程中對不同區域的不同曝光量控制，定義單層光阻形成具有特定尺寸且不同厚度之結構，接著配合回流(reflow)即可利用一連續製程製作出結合超半球固態浸沒式透鏡(solid immersion lens)、奈米微孔、金屬線圈、空氣軸承之磁光(MO)讀取頭，而不需精密昂貴的設備，並可批次大量生產，免去組裝的步驟，並且不用高精密度之儀器即可製作，達到高資料儲存與複寫。
隨機存取記憶體陣列結構
(2006-08-21)
鄭東栓
;
黃威
本發明提供一種隨機存取記憶體陣列結構，其係將一隨機存取記憶體陣列結構分成複數個資料區塊，每一資料區塊以陣列方式排列，且每一資料區塊連接有一及閘及電源閘，利用一編碼裝置使一數據資料進行儲存或讀取動作。本發明能有效使電路減少漏電流的產生，進而大幅降低動態功率之消耗。
Identification of mechanical properties of elastically restrained laminated composite plates using vibration data
(2006-08-22)
Lee, C. R.
;
Kam, T. Y.
;
機械工程學系
;
Department of Mechanical Engineering
A nondestructive evaluation method using vibration data to determine mechanical properties (material and spring constants) of elastically restrained laminated composite plates is presented. The Rayleigh-Ritz method in which a set of Legendre's polynomials is adopted to approximate the plate deflection is used to determine the theoretical natural frequencies of the elastically restrained laminated composite plates. A number of natural frequencies extracted from the impulse vibration test data of the laminated composite plates supported by elastic restraints at both the edges and centers of the plates are used in the present method to determine the mechanical properties of the plates. The sum of the squared differences function which measures the differences between the experimentally and theoretically predicted natural frequencies of the elastically restrained laminated composite plates is established. The identification of the plate mechanical properties is then formulated as a constrained minimization problem in which the mechanical properties are determined by making the sum of the squared differences function a global minimum. The feasibility and accuracy of the proposed method are studied by means of several numerical examples on the mechanical properties identification of elastically restrained laminated composite plates with different layups made of various composite materials. Experimental investigation of the mechanical properties identification of several elastically restrained laminated composite plates has been performed to illustrate the applications of the present method. It has been shown that the present method can produce good estimates of the mechanical properties of the elastically restrained laminated composite plates in an efficient and effective way. (c) 2006 Elsevier Ltd. All rights reserved.
A computational study on the kinetics and mechanism for the unimolecular decomposition of o-nitrotoluene
(2006-08-24)
Chen, S. C.
;
Xu, S. C.
;
Diau, E.
;
Lin, M. C.
;
應用化學系分子科學碩博班
The kinetics and mechanism for the unimolecular decomposition of o-nitrotoluene (o-CH3C6H4NO2) have been studied computationally at the G2M(RCC, MP2)//B3LYP/6-311G(d, p) level of theory in conjunction with rate constant predictions with RRKM and TST calculations. The results of the calculations reveal 10 decomposition channels for o-nitrotoluene and its six isomeric intermediates, among them four channels give major products: CH3C6H4 + NO2, C6H4C(H) ON (anthranil) + H2O, CH3C6H4O (o-methyl phenoxy) + NO, and C6H4C(H-2) NO + OH. The predicted rate constants in the 500-2000 K temperature range indicate that anthranil production, taking place initially by intramolecular H-abstraction from the CH3 group by NO2 followed by five-membered ring formation and dehydration, dominates at temperatures below 1000 K, whereas NO2 elimination becomes predominant above 1100 K and CH3C6H4O formation by the nitro-nitrite isomerization/decomposition process accounts for only 5-11% of the total product yield in the middle temperature range 800-1300 K. The branching ratio for CH2C6H4NO formation by the decomposition process of CH2C6H4N(O)OH is negligible. The predicted high-pressure-limit rate constants with the rate expression of 4.10 x 10(17) exp[-37000/T] s(-1) for the NO2 elimination channel and 9.09 x 10(12) exp[-25800/T] s(-1) for the H2O elimination channel generally agree reasonably with available experimental data. The predicted high-pressure-limit rate constants for the NO and OH elimination channels are represented as 1.49 x 10(14) exp[-30000/T] and 1.31 x 10(15) exp[-38000/T] s(-1), respectively.
Thermally-induced order-order transition of DNA-cationic surfactant complexes
(2006-08-29)
Hsu, Wei-Long
;
Li, Yen-Cheng
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Chen, Hsin-Lung
;
Liou, Willisa
;
Jeng, U-Ser
Polyanionic DNA interacts with cationic amphiphiles to form electrostatic complexes exhibiting rich self-assembled structures. This type of complex has been considered as a nonviral carrier in gene therapy and as a template for nanostructure construction. Here we report a thermally-induced phase transition of the complexes of DNA with the mixtures of a cationic surfactant, dodecyltrimethyl bromide (DTAB), and a neutral lipid, dioleoylphosphatidylethanolamine (DOPE), in fully hydrated state. An order-order transition between a multilamellar (L-alpha(c)) phase and an inverted hexagonal (H-II(c)) phase was found to occur with the transition temperature adjustable by the DTAB-to-DNA base pair molar ratio (x) and DOPE-to-DTAB molar ratio (m). The stability of the L-alpha(c) phase was enhanced at lower m and x, as the L-alpha(c)-to-H-II(c) transition temperature increased with the decreases of these two parameters. The suppression of L-alpha(c)-to-H-II(c) transition at lower x was attributed to the lower entropic gain from the counterion release due to the presence of uncomplexed DNA in the bulk solution.
ESD protection circuit
(2006-08-29)
Ker
;
Ming-Dou
;
Lin
;
Kun-Hsien
The claimed invention discloses an ESD protection circuit that is applied to an IC with power-down-mode operation. When the IC goes into power-down-mode operation, leakage current and charging from the I/O pad to the VDD power line could be prevented by applying the present invention. Therefore, the malfunction of the IC can be avoided. There still have two ESD clamp circuits respectively connected between the VDD power line and the VSS power line and between ESD bus line and VSS power line, so as to achieve the whole chip ESD protection scheme. The present invention can prevent ESD protection circuit from resulting in leakage current or malfunction under power-down-mode operation, and moreover achieve whole chip ESD protection scheme.
Novel dendritic light-emitting materials containing polyhedral oligomeric silsesquioxanes core
(2006-08-30)
Chen, Kuei-Bai
;
Chang, Yueh-Ping
;
Yang, Sheng-Hsiung
;
Hsu, Chain-Shu
;
應用化學系
A new series of star-like light-emitting materials (POSS1, POSS2 and POSS3) were synthesized by hydrosilylation of the polyhedral oligomeric silsesquioxane with 4,4'-bis(4-(di-(4-methylphenyl)amino)styryl)-2-(hexan-1-yloxy)-5-(10-undecen-1-yloxy)benzene (Cl), 4,4'-bis [(E)-2-(N-ethylcarbazoyl)ethenyl]-2-(hexan-1-yloxy)-5-(10-undecen-1-yloxy)benzene (C2), and Iridium(III) bis(2-phenylpyridine-C-2-N') (13-teradecenyl acetonate) (0), respectively. All synthesized materials are soluble in common organic solvents, such as chloroform, toluene and 1,2dichloroethane, and exhibit good film-forming properties. Therefore, they can be used to fabricate devices by spin-coating. The aggregation of peripheral chromophores can be prevented by the rigid POSS core. A double-layer, light-emitting diode with the configuration of indium-tin oxide/poly(ethylene 3,4-dioxythiophene)/POSS1/Ca/Al was fabricated using POSS1 as the active layer. The device emitted green light with a maximum brightness of 115 cd/m(2) and a current yield of 0.07 cd/A. When the light-emitting layer is blended with 0.8% electron-transport material, 2-(4'-tert-butylphenyl)-5-(4'-diphenyl)-1,3,4-oxadiazole, the maximum brightness and current yield of the device can reach 1469 cd/m(2) and 0.8 cd/A, respectively. The performance of a POSS2 device with the same device structure can reach 1102 cd/m(2) and 0.88 cd/A. POSS3 is a kind of triplet material and blended with 4,4-NN-dicarbazole-biphenyl as host material, to fabricate the light-emitting device. The maximum brightness and current yield reach 1008 cd/m(2) and 1.04 cd/A, respectively. Blending with 1,3,5-tris(2-N-phenylbenzimi dazolyl)benzene as the hole-blocking, material yields a maximum brightness and current yield of 1172 cd/m(2) and 3.99 cd/A. (c) 2006 Elsevier B.V. All rights reserved.
Tunable optical group delay in quantum dot vertical-cavity surface-emitting laser at 10 GHz
(2006-08-31)
Peng, P. C.
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Lin, C. T.
;
Kuo, H. C.
;
Lin, G.
;
Tsai, W. K.
This investigation experimentally demonstrates tunable optical group delay in a 1.3 mu m quantum dot vertical-cavity surface-emitting laser (QD VCSEL). The QD VCSEL is fabricated on a GaAs substrate. Tunable delays are achieved by varying the bias currents, and the maximum delay of 42 ps at 10 GHz has been demonstrated at room temperature.
閱讀精神病
(國立陽明交通大學出版社, 2006-09-01)
沈志中
佛洛伊德自始便企求能夠將當時定義未明的精神病，特別是妄想症編納入其系統化的知識之內。直到佛洛伊德著作晚期，仍然可見精神分析跨入精神病境地的想望。但精神病這個難題始終不被自詡為科學的精神分析知識所馴服。若精神分析為研究意識之外者－無意識－的學說，則精神病這個不被知識馴化的課題是否構成吾人意識之外的之外？一種無意識的無意識？精神病之於精神分析，正有如歇斯底里之於十九世紀末的精神醫學。歇斯底里研究顯示出精神分析之特殊性；但唯有精神病研究才能讓我們詰問精神分析本質性的局限與內在跨越界線的知識慾望。處於類似的處境，拉岡(J. Lacan)不也是透過妄想症研究而從傳統精神醫學踏入精神分析？因此，毫無疑問地，要探討精神分析學之知識論本質，不得不經由精神病與精神分析關係的重新反省。
死亡驅力，或是解離之力：克莉絲蒂娃文化理論的政治與倫理
(國立陽明交通大學出版社, 2006-09-01)
劉紀蕙
本文討論克莉絲蒂娃如何透過佛洛伊德的語言理論，解決了西方思想主客對立的二元辯證，而展開了以精神分析出發的政治觀與倫理觀。1980、90年代英美女性主義者批評克莉絲蒂娃追隨佛洛伊德，而過於陽具中心主義。但是，仔細閱讀克莉絲蒂娃早期到晚期的作品，我們不難發現她所持續進行的，正是對於任何單一邏輯封閉系統的解構。本文以三個階段展開：首先，從歐陸當代哲學重探政治性概念的脈絡出發，檢視克莉絲蒂娃的政治性立場。其次，進入佛洛伊德語言理論所包含的力的概念、真實與符號化的辯證等問題，討論克莉絲蒂娃如何透過佛洛伊德的理論，發展符號驅力與象徵鍊結的連續體概念，如何指出文化現象，包括理性知識與真理陳述，都有其內在的分裂、壓抑、否認、拒斥，以及克莉絲蒂娃如何利用佛洛伊德的死亡驅力概念，指出挑戰社會共識的壓迫性與專斷，揭露理性知識與真理體系背後隱藏的排他性邏輯，需要有解離之力。這個解離之力，就是佛洛伊德所說的「知性化」過程，也是克莉絲蒂娃所說的思想的「反叛／迴轉」。反叛，不是對立面的僵持或是破壞，而是心靈空間不斷打開、離開、重組、轉向。第三個階段進入克莉絲蒂娃所提出的政治性空間，或是她所謂的「象徵性國家」之概念。透過解離之力，一個文化才能夠提供具有質疑、反叛、迴轉、更新、聆聽與創造的政治性空間。對克莉絲蒂娃而言，國家不是以語言、血緣或是土地而連結的民族國家，而是以象徵契約之概念作為基礎，在自由與平等的個人之間，建立一種過渡式的契約與文化的「國家」。本文以倫理的思考作為結語。持續思索與揭露語言過程中被隱藏的因果與倫理的沈默邏輯，朝向不再被質疑的絕對標準背後所隱藏的暴力開始發問，便是倫理的起點。
Homologous response regulators KvgA, KvbA and KvhR regulate the synthesis of capsular polysaccharide in Klebsiella pneumoniae CG43 in a coordinated manner
(2006-09-01)
Lin, Ching-Ting
;
Huang, Teng-Yi
;
Liang, Wan-Chun
;
Peng, Hwei-Ling
;
生物科技學系
On the basis of phenotypic analysis, the Klebsiella pneumoniae CG43 derived mutants with deletions of the gene encoding respectively the response regulators KvgA, KvhA, and KvhR were classified into two groups. Group I bacteria carrying either kvgA(-) or kvhR(-) exhibited less mucoidy, lower level of capsular polysaccharide (CPS) synthesis and higher LD50 than the parental strain. No apparent change of the group II, including kvhA(-) and hvhA(-)kvhR(-) mutants, was observed. However, the mucoidy of kvhA(-)kvhR(-) mutant was found to be diminished after introducing into a kvhA(-) expressing plasmid. Via promoter-lacZ fusion analysis, kvhA deletion was found to reduce kvhR expression. A regulatory role of KvhA for the expression of kvhR was supported further by EMSA showing a specific binding of KvhA to the putative promoter of kvhR. The promoter activity measurement and EMSA also revealed that KvgA acted as an autoregulator and an activator for the expression of kvhAS and kvhR. In addition, deletion of kvgA suppressed slightly the promoter activity of the cps-orf16-17, and the expression of all three cps transcripts orf1-2, orf3-15, and orf16-17 were reduced in the kvhR(-) mutant. These suggest that the three homologous response regulators interact to control, in coordination, the bacterial cps expression.
具3D聲場效果之陣列式助聽器
(2006-09-01)
白明憲
;
林振邦
本發明係一種具3D聲場效果之陣列式助聽器，其係以陣列式麥克風接收至少一聲源訊號並輸出至數位訊號處理器，數位訊號處理器依據聲源訊號進行程序建立聲束及掃描該聲源訊號之方向，陣列訊號處理方法包含超指向性法(super directive method)及延遲加成法(delay and sum method)，利用陣列訊號處理方法進行方向估計及聲束形成，係利用超指向性法提高聲源指向性與訊號對聲源之雜訊比以得到最大聲源訊號，利用延遲加成法進行方向估計以找出聲源方向，搭配頻率補償系統及頭部轉移函數以產生3D聲場效果。
Secure authentication protocols resistant to guessing attacks
(2006-09-01)
Luo, Jia-Ning
;
Shieh, Shiuhpyng
;
Shen, Ji-Chiang
;
資訊工程學系
;
Department of Computer Science
Users are normally authenticated via their passwords in computer systems. Since people tend to choose passwords that can be easily remembered, the systems are under the threat of guessing attacks. Many authentication and key distribution protocols have been proposed to protect user passwords from guessing attacks. However, these protocols either are limited to some specific environments or incur high computation and communication costs. In the paper, we first specify five common forms of guessing attacks, which are used to determine whether a protocol is vulnerable to those attacks. Based on these common forms, some guidelines are provided for developing secure protocols that can be used in both symmetric and asymmetric cryptosystems to defend against guessing attacks. Finally, we enhance the well-known authentication system Kerberos and propose two authentication and key distribution protocols, which are both resistant to guessing attacks.