Browsing by Issue Date, starting with "2006-08-22"

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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
;
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.
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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.
EDFA-free all-optical 2R regeneration using a compact self-seeded Fabry-Perot laser diode (vol 18, pg 1112, 2006)
(2006-09-01)
Chien, Hung-Chang
;
Lee, Chien-Chung
;
Lin, Chun-Ting
;
Chi, Sien
;
光電工程學系
由金氧半場效電晶體臨界電壓與熱效應電壓所組成之參考電壓電路
(2006-09-01)
洪崇智
本發明係揭露一種由金氧半場效電晶體臨界電壓與熱效應電壓所組成之參考電壓電路。本發明以現有的能隙電壓架構為基礎，並使用了工作於弱反轉層的場效電晶體代替傳統的雙載子電晶體，以產生與溫度係數正相關之電流，再由金氧半場效電晶體臨界電壓產生另一與溫度係數負相關之電流，結合以上兩個電流而產生一不隨溫度變化而改變之穩定參考電流，再將此電流通過一電阻，以產生一與溫度係數完全不相關之參考電壓。
Purification, crystallization and preliminary X-ray crystallographic analysis of chitinase from Bacillus cereus NCTU2
(2006-09-01)
Kuo, Chueh-Yuan
;
Wu, Yue-Jin
;
Hsieh, Yin-Cheng
;
Guan, Hong-Hsiang
;
Tsai, Huei-Ju
Chitinases (EC 3.2.1.14) are found in a broad range of organisms, including bacteria, fungi and higher plants, and play different roles depending on their origin. A chitinase from Bacillus cereus NCTU2 (ChiNCTU2) capable of hydrolyzing chitin as a carbon and nitrogen nutrient has been identified as a member of the family 18 glycoside hydrolases. ChiNCTU2 of molecular weight 36 kDa has been crystallized using the hanging-drop vapour-diffusion method. According to the diffraction of chitinase crystals at 1.10 angstrom resolution, the crystal belongs to space group P2(1), with unit-cell parameters a = 50.79, b = 48.79, c = 66.87 angstrom, beta = 99.31 degrees. Preliminary analysis indicates there is one chitinase molecule in the asymmetric unit, with a solvent content of 43.4%.
A max-min fairness congestion control for layered streaming of scalable video
(2006-09-01)
Hsiao, Hsu-Feng
;
Hwang, Jenq-Neng
;
資訊工程學系
;
Department of Computer Science
In a best-effort networking environment, efficient and fair congestion control is highly desired for every traffic flow to share the bandwidth appropriately. This paper proposes a congestion control algorithm for user datagram protocol rate-based layered streaming of scalable video, e.g., 3-D wavelet based scalable video streaming, which provides a variety of video bit rates. This proposed congestion control mechanism, as an extension of explicit control protocol that is a newly proposed congestion control. protocol believed to be superior to transport control protocol, accommodates both window-based and rate-based flows to the heterogeneous network environment which can include wired and wireless channels. This paper further introduces the notion of reserved packet length so that the traffic of layered video can better share the bandwidth of a network by taking account of the max-min fairness with other traffic.
Epitaxial layer of MgO (001) grown on Si(001)wafer by e-beam evaporation
(2006-09-01)
Lee, M. D.
;
Lo, C. K.
;
Peng, T. Y.
;
Yau, K. L.
;
Chen, S. Y.
MgO(0 0 1) has been growing successfully on Fe/Pd/Cu/Si(1 0 0) by e-beam evaporation as examined by X-ray diffraction and high resolution transmission microscope. We present the magnetic peculiarity of crystal structure Fe(0 0 1)/Pd(0 0 1)/Cu(0 0 1) on Si(0 0 1) substrate. The magnetic properties of the sample were measured by magneto-optical Kerr effect which shows an in-plane magnetocrystalline anisotropy. (C) 2006 Elsevier B. V. All rights reserved.
NCTU6 wins Connect6 tournament
(2006-09-01)
Wu, I-Chen
;
Yen, Shi-Jim
;
資訊工程學系
;
Department of Computer Science
Antiresonant reflecting optical waveguides polarization beam splitters
(2006-09-01)
Huang, Yang-Tung
;
Jang, Chiou-Hung
;
Hsu, Shih-Hsin
;
Deng, Jau-Jan
;
電子工程學系及電子研究所
Three different configurations of polarization beam splitters based on antiresonant reflecting optical waveguide (ARROW) structures are proposed. The polarization splittings are attained by utilizing various characteristics of basic ARROW and/or ARROW-B. In comparison with conventional waveguides, ARROW structures utilizing antiresonant reflection as the guiding mechanism can have large core sizes compatible with single-mode fibers and, thus, provide better coupling. Design principles and characteristics of these ARROW polarization beam splitters are discussed in detail, and the simulation results show that all these devices have good polarization discrimination with crosstalk < -20 dB.
Threshold-voltage-compensation methods for AMOLED pixel and analog buffer circuits
(2006-09-01)
Chen, Bo-Ting
;
Tai, Ya-Hsiang
;
Wei, Ying-Jyun
;
Tsai, Chun-Chien
;
Huang, Chun-Yao
New pixel-circuit designs for active-matrix organic light-emitting diodes (AMOLEDs) and a new analog buffer circuit for the integrated data-driver circuit of active-matrix liquid-crystal displays (AMLCDs) and AMOLEDs, based on low-temperature polycrystalline-silicon thin-film transistors (LTPS-TFTs), were proposed and verified by SPICE simulation and measured results. Threshold-voltage-compensation pixel circuits consisting of LTPS-TFTs, an additional control signal line, and a storage capacitor were used to enhance display-image uniformity. A diode-connected concept is used to calibrate the threshold-voltage variation of the driving TFT in an AMOLED pixel circuit. An active load is added and a calibration operation is applied to study the influences on the analog buffer circuit. The proposed circuits are shown to be capable of minimizing the variation from the device characteristics through the simulation and measured results.
Effect of photonic crystal band gap on rotation of hollow oval Te rods in triangular lattice
(2006-09-01)
Chang, Kuo-Pin
;
Yang, Su-Lin
;
電子物理學系
;
Department of Electrophysics
The band structures and field patterns of two-dimensional (2D) triangular photonic crystals with hollow tellurium (Te) rods are calculated using the plane-wave method. Inner-rod and whole-rod rotations are considered to investigate how the rotational and structural symmetries affect E- and H-polarization modes. It is indicated that the H-polarization modes are strongly affected by the shape and interaction between the fields of the rods. In addition, the effect of rotational symmetry on H-polarization modes must be considered when whole rods are rotated. The E-polarization modes for both types of rotations are strongly related to the shape of the rods. Moreover, H-polarization modes determine the absolute photonic band gap (PBG) width when whole rods are rotated, while E-polarization modes determine the absolute PBG width when inner rods are rotated.