Browsing by Issue Date, starting with "1992-07-01"

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A NEW-WORLD PERSPECTIVE FOR THE REPUBLIC OF CHINA
(1992-07-01)
YUNG, W
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交大名義發表
;
National Chiao Tung University
As the Republic of China (ROC) enters into the 1990s, its political system is under tremendous pressure to adapt to its changing internal and external environments. The purposes of this article are: to present the arguments as to why the ROC urgently needs a new world perspective; to propose a new outlook for the ROC toward its external environment, and finally, to identify the areas wherein the ROC must develop new perspectives, so as to charter a course of policy planning which will be beneficent, not only for the government and people in Taiwan, but also for the Chinese people as a whole. Following a detailed analysis of the internal situation as well as the external environment of the ROC, this article puts forward a series of suggestions regarding a new world perspective for the ROC. First, it argues for a positive and active policy toward mainland China aimed at "peaceful transformation," while putting off political negotiation until a later date. Second, it suggests the adoption of the "multi-system nations" concept coupled with the application of "dual recognition" schemes as a progressive strategy for expanding the diplomatic front of the ROC. And finally, the author reminds the leaders of the ROC government that elite solidarity and future-oriented policy planning are the two key factors which will determine whether or not the ROC will successfully overcome its present and future challenges and pave the way for a higher level of national development in the twenty-first century.
NUMERICAL-ANALYSIS OF THE PHOTOEFFECTS IN GAAS-MESFETS
(1992-07-01)
LO, SH
;
LEE, CP
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
The photoeffects on the I-V characteristics of GaAs MESFET's have been studied by a two-dimensional numerical method. It is theoretically verified that the photovoltaic effect occurring at the channel/substrate interface is responsible for the substantial increase of the drain current. The reverse gate current due to illumination is caused by sweep-out by the high electrical field in the gate depletion region, where a large gradient in the depth profile of the hole Fermi energy is found. For devices with a lightly doped n-type buffer layer, the increase of the drain current is less than for devices without a buffer layer, but is still substantial.
STABILITY OF A RATE GYRO
(1992-07-01)
GE, ZM
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CHEN, CJ
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交大名義發表
;
機械工程學系
;
National Chiao Tung University
AN APPROXIMATE METHOD FOR LOCAL OPTIMA FOR NONLINEAR MIXED INTEGER PROGRAMMING-PROBLEMS
(1992-07-01)
LI, HL
;
交大名義發表
;
資訊管理與財務金融系註：原資管所+財金所
;
National Chiao Tung University
;
Department of Information Management and Finance
For a nonlinear 0-1 integer programming problem with constraint set X = (x1,...,x(n)), we first add new constraints [GRAPHICS] to the constraint set, thus to convert the integer problem into a nonlinear programming problem. Then we utilize a modified penalty function method to solve this nonlinear program to obtain a local optima Running the proposed method by a widely commercialized nonlinear program software shows that this method is more convenient than current approaches as branch-and-bound method and implicit enumeration method. One issue remained for studies is to expand this method into a global method by systematically generating suitable starting points then to perform optimization processes from each of these points.
OPTIMAL SAMPLING IN THE IDENTIFICATION OF A RANDOMLY EXCITED STRUCTURAL SYSTEM
(1992-07-01)
LEE, AC
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CHEN, JH
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交大名義發表
;
機械工程學系
;
National Chiao Tung University
ANALYSIS OF AN INTEGRATED MULTIPLEXER WITH ALL QUEUEABLE AND FIXED-LENGTH TRAFFICS IN INTERMEDIATE NODE
(1992-07-01)
CHANG, CJ
;
WANG, SY
;
交大名義發表
;
電信工程研究所
;
National Chiao Tung University
An integrated multiplexer in intermediate node is analyzed. The multiplexer is modeled as a system with multiple synchronous servers (channels) and having two kinds of customers. Between the two, one is wideband (WB) and the other is narrowband (NB); they are queueable with the same deterministic service time. The WB customer is given higher priority of channel access than the NB. To incorporate the delay constraint of WB, we use a simple instant discarding scheme(8) for WB. As a result, the system states defined just after the beginning of a slot form an one-dimensional embedded Markov chain. This makes the analysis computationally tractable. The performance measures such as queue length distribution, average blocking probability, and average waiting time are obtained, particularly, the waiting time distribution. Some interesting numerical examples are discussed. Simulation results are also provided to help verify the validity of analysis.
FEGE LIQUID-METAL ION-SOURCE FOR MASKLESS ISOLATION IMPLANTS IN INP
(1992-07-01)
CHU, CH
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BARR, DL
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HARRIOTT, LR
;
WADE, HH
;
奈米中心
A Fe-Ge alloy was used to fabricate a liquid metal ion source (LMIS) for our focused ion beam system. The iron ion and germanium ions can be utilized to create semi-insulating regions for device isolation and n-type doping in InP. The properties of the Fe-Ge LMIS were characterized by measuring the ion current-extraction voltage characteristics, the mass spectrum of the ion species in the ion beam, and the stability of the source current. The changes of resistivity in InP before and after Fe + + implant and after thermal annealing were measured in mesa-etched four-terminal test structures. The resistivity of as-implanted samples increases about four orders of magnitude compared with original resistivity. After rapid thermal annealing at 400-degrees-C for 10 s, the resistivity is about two times larger than that of as-implanted sample.
TRANSIENT COMBINED CONDUCTION AND RADIATION IN ANISOTROPICALLY SCATTERING SPHERICAL MEDIA
(1992-07-01)
CHU, HS
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WENG, LC
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機械工程學系
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Department of Mechanical Engineering
STRUCTURE OF EVEN GE ISOTOPES BY MEANS OF INTERACTING BOSON MODEL WITH A FERMION PAIR MODEL
(1992-07-01)
HSIEH, ST
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CHIANG, HC
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CHUU, DS
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電子物理學系
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Department of Electrophysics
The energy levels of the even-even Ge isotopes with mass number between 64 and 78 are studied in the model of the traditional interacting boson approximation. To account for the multiple band structure of these isotopes, one boson is allowed to break and form a fermion pair. The two fermions are allowed to excite to f5/2 and g9/2 Single-particle orbitals. It was found that the energy levels of the Ge-64-78 isotopes can be reproduced reasonably.
OPEN-LOOP FIBER OPTIC GYROSCOPE WITH WIDE DYNAMIC-RANGE
(1992-07-01)
CHIEN, PY
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交大名義發表
;
光電工程學系
;
National Chiao Tung University
;
Department of Photonics
An open-loop, wide dynamic range, fiber optic gyroscope has been demonstrated by using the PLL phase tracking technique. This technique provides a linear output of an open-loop gyroscope with the Sagnac phase shift up to 2N-pi-rad, N=2n, is where n an integer number.
ANISOTROPIC MAGNETIC-PROPERTIES OF BI2SR2CUO6+DELTA SINGLE-CRYSTAL
(1992-07-01)
SHI, JB
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CHIOU, BS
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HO, JC
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KU, HC
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電控工程研究所
Single crystals of Bi2Sr2CuO6+delta were synthesized and characterized by X-ray diffraction. The Bi(2201) sample remains not superconducting or magnetically ordered down to 5 K. With an applied magnetic field perpendicular or parallel to the c-axis, magnetic measurements yielded anisotropic magnetic susceptibilities chi(c)(H perpendicular-to c) and chi(ab)(H parallel-to c). Both can be fitted to the sum of a temperature-independent chi(0) and a Curie-Weiss term C/(T + theta(p)) in the temperature range between 5 and 300 K, with a common Curie constant C = 1.0 x 10(-2) cm3 K/mol and Curie-Weiss paramagnetic intercept theta(p) = + 1.1 K. Since the resulting Curie-Weiss term is the same for both directions, the overall anisotropy DELTA(chi) = chi(c) - chi(ab) = DELTA(chi-0) is also temperature independent. Its magnitude, 3.3 x 10(-5) cm3/mol, however, is lower than the corresponding values for Bi(2212) (2.3 x 10(-4) cm3/mol) and Bi(2223) (5.8 x 10(-4) cm3/mol).
MDL (METHODOLOGY DEFINITION LANGUAGE) - A LANGUAGE FOR DEFINING AND AUTOMATING SOFTWARE-DEVELOPMENT PROCESSES
(1992-07-01)
CHEN, JY
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HSIA, P
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資訊工程學系
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Department of Computer Science
This paper discusses a Methodology Definition Language that can be used to define the software development method. Together with the support of the language processor called the environment generating system, this language can be used to define a specially tailored method for any particular software development process and generate a computer-guided environment for the method defined. The syntax of the language is defined using the BNF grammar, and the semantics of the language is defined by an executable language (a command language). A prototype system of this language has been implemented under the VAX/VMS system. Experiences using this prototype to exercise methodologies show that the approach is very versatile and may improve the quality of development process.
A METHOD FOR MEASURING THE SPHERICAL-ABERRATION OF A CYLINDRICAL OPTICAL-ELEMENT BY FOURIER-TRANSFORM TECHNIQUE
(1992-07-01)
CHANG, CW
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SU, DC
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交大名義發表
;
光電工程學系
;
National Chiao Tung University
A simple method of using Fourier transform technique for measuring the spherical aberration of a cylindrical optical element is presented. First, a collimated monochromatic light passes through a linear grating and a tested cylindrical optical element, then the deformed fringes are obtained in the observation plane. Next, the fringes are analyzed with the techniques of Fourier transform, bandpass filtering and inverse Fourier transform and finally the spherical aberration of the tested element is obtained.
DESIGNING A COMPLEMENTARY DESIGN RULE CHECKER BASED ON A BINARY BALANCED QUAD LIST QUAD TREE
(1992-07-01)
HSIAO, PY
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YAN, JT
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交大名義發表
;
資訊工程學系
;
National Chiao Tung University
An efficient real time VLSI-CAD tool, the complementary design rule checker (CDRC), composed of one interactive phase and one batch phase is presented. It is a general geometrical design rule model which checks some of the layout constraints in the interative phase and the other constraints in the batch phase. Those classified constraints are disjointed, and each one of them should be checked only once either during the interactive or batch phase. This system and the embedded layout editor are designed on the basis of the binary balanced quad list quad tree (BBQLQT) and its region query functions. The BBQLQT is more efficient than the most recently published spatial data structure, the Weyten's quad list quad tree. One day, provided that the BBQLQT has being further improved, the performance of our system will be promoted without giving more additional design effort. This system is therefore proven to be fully modularised and independent of any of the other spatial data structures.
GRADED-GAP A-SIC-H P-I-N THIN-FILM LIGHT-EMITTING-DIODES
(1992-07-01)
HONG, JW
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SHIN, NF
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JEN, TS
;
NING, SL
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CHANG, CY
In order to improve the performance of hydrogenated amorphous-silicon carbide (a-SiC:H) p-i-n thin-film light-emitting diodes (TFLED's), a p-i-n TFLED with a graded p-i junction has been proposed and fabricated. The electroluminescence (EL) intensity of the proposed TFLED was more than 100 times higher than that of the basic p-i-n TFLED and about 35 times lower than that of the conventional green LED, at the same injection current density. This significant improvement was attributed to the better interface property and enhancement of hole injection efficiency by using the graded-gap p-i junction.
APPLICATION OF BEM (BOUNDARY ELEMENT METHOD)-BASED ACOUSTIC HOLOGRAPHY TO RADIATION ANALYSIS OF SOUND SOURCES WITH ARBITRARILY SHAPED GEOMETRIES
(1992-07-01)
BAI, MR
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交大名義發表
;
機械工程學系
;
National Chiao Tung University
;
Department of Mechanical Engineering
A method employing holograms that conform with arbitrarily shaped sources has been developed for enhancing conventional near-field acoustic holography, which has been limited to sources with simple geometries, e.g., planar or cylindrical surfaces. Four holography transformation algorithms have been developed, based on acoustic holography theory and the boundary element method (BEM). Singular value decomposition (SVD) has been incorporated into the algorithms in order to alleviate the ill-posed nature frequently encountered in backward reconstruction of a field. A pulsating sphere, a cylinder with spherical endcaps, and a vibrating piston set in a rigid sphere have been adopted in a numerical simulation for verifying the algorithms. Satisfactory agreement has been achieved between the holographically transformed results and the analytical solutions.
COPPER VALENCY OF SUPERCONDUCTING PHASES IN THE PB-DOPED BI-SR-CA-CU-O SYSTEM
(1992-07-01)
CHEN, FH
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KOO, HS
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WU, SC
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TSENG, TY
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HORNG, SR
Pb-doped Bi-Sr-Ca-Cu high-T(c) superconducting oxides have been prepared by a modified sol-gel process via the EDTA route. Upon decomposing the X-ray photoemission spectrum of the Cu 2p3/2 core level of the superconducting oxide into three components Cu1+, Cu2+ and Cu3+, we have found an obvious trend: the corresponding [Cu1+]/[Cu2+] ratio increased as more 110 K phase was formed in the sample. According to this trend, a defect model was proposed; it can reasonably explain some previous experimental results, such as a reduced oxygen atmosphere sintering, which effectively facilitates the formation of the 110 K phase, and the coexistence of copper and oxygen vacancies in Bi-system superconductors, observed by high-resolution transmission electron microscopy. On the other hand, the dimerization of holes in oxygen sites was also suggested to be a possible mechanism responsible for the increase in the ratio of [Cu1+]/[Cu2+].
TRANSIENT COMBINED CONDUCTION AND RADIATION IN AN ABSORBING, EMITTING AND ANISOTROPICALLY-SCATTERING MEDIUM WITH VARIABLE THERMAL-CONDUCTIVITY
(1992-07-01)
TSENG, CJ
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CHU, HS
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交大名義發表
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機械工程學系
;
National Chiao Tung University
ACOUSTIC-EMISSION CHARACTERISTICS OF MORTAR UNDER COMPRESSION
(1992-07-01)
WENG, CC
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TAM, MT
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LIN, GC
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交大名義發表
;
土木工程學系
This research is devoted to the study of the characteristics of acoustic emission (AE) signals of mortar under uniaxial compression. A total of 40 specimens were tested, in which the water-cement ratio, age, compressive strength and strain were the major parameters of mortar related to the AE signals. In addition, different compressive modes were used in the tests in order to investigate the AE Kaiser effect in mortar. From the test results, good correlation between the AE signals and the major parameters of mortar was observed. The experimental findings may provide useful information for further understanding of the AE characteristics of concrete and reinforced concrete.
A STATISTICAL-MODEL BASED FUNDAMENTAL-FREQUENCY SYNTHESIZER FOR MANDARINE SPEECH
(1992-07-01)
CHEN, SH
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CHANG, S
;
LEE, SM
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電信工程研究所
;
電信研究中心
A novel method based on a statistical model for the fundamental-frequency (F0) synthesis in Mandarin text-to-speech is proposed. Specifically, a statistical model is employed to determine the relationship between F0 contour patterns of syllables and linguistic features representing the context. Parameters of the model were empirically estimated from a large training set of sentential utterances. Phonologic rules are then automatically deduced through the training process and implicitly memorized in the model. In the synthesis process, contextual features are extracted from a given input text, and the best estimates of F0 contour patterns of syllable are then found by a Viterbi algorithm using the well-trained model. This method can be regarded as employing a stochastic grammar to reduce the number of candidates of F0 contour pattern at each decision point of synthesis. Although linguistic features on various levels of input text can be incorporated into the model, only some relevant contextual features extracted from neighboring syllables were used in this study. Performance of this method was examined by simulation using a database composed of nine repetitions of 112 declarative sentential utterances of the same text, all spoken by a single speaker. By closely examining the well-trained model, some evidence was found to show that the declination effect as well as several sandhi rules are implicitly contained in the model. Experimental results show that 77.56% of synthesized F0 contours coincide with the VQ-quantized counterpart of the original natural speech. Naturalness of the synthesized speech was confirmed by an informal listening test.