Browsing by Issue Date, starting with "1992-04-15"

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ANISOTROPIC IRREVERSIBILITY LINES FOR C-AXIS ALIGNED (BI, PB)2CA2SR2CU3O10+DELTA POWDERS
(1992-04-15)
SHI, JB
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CHIOU, BS
;
KUO, PL
;
KU, HC
;
電控工程研究所
Anisotropic irreversibility lines due to thermal fluctuation for quasi-two-dimensional high-T(c) superconductors were observed in c-axis-aligned powders of the (Bi, Pb)2Ca2Sr2Cu3O10+deltaBi(2223) compound with T(c) = 108 K. The anisotropic ratio H(r)(perpendicular-to c)/H(r)(parallel-to c) decreases sharply from 13.6 at 100 K to low values of 3.2 at 80 K and 3.1 at 70 K. The simple 3D-like power law H(r)=a.(1 - T/T(c))n was observed only in the low field region (less-than-or-equal-to 200 G) with n=2.19 for H perpendicular-to c and 2.99 for H parallel-to c. In the higher field region up to 4 kG, the temperature dependence of H(r)(T) lines changes into a 2D-like exponential function H(r) = b.exp (-T/T0) due to the breakdown of the interlayer and/or intralayer coupling of the conduction channel which consists of three Cu-0 planes, with T0 = 14.2 K for H perpendicular-to c and 13.7 K for H parallel-to c. The magnetic susceptibility ratio chi(c)/chi(ab) for this highly anisotropic superconductor in a low applied field of 8 G increases sharply from 9.8 at 5 K to 17.9 near T(c).
管管作品三首
(1992-04-15)
管管
管管作品三首
(1992-04-15)
管管
管管作品三首
(1992-04-15)
管管
TRIBOLOGICAL BEHAVIORS OF THE DIAMOND-COATED CEMENTED CARBIDE TOOLS WITH VARIOUS COBALT CONTENTS
(1992-04-15)
HUANG, TH
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KUO, CT
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CHANG, CS
;
KAO, CT
;
WEN, HY
管管作品三首
(1992-04-15)
管管
黑廟黃廟綠廟藍廟金廟
(1992-04-23)
管管
IMAGE INTERPOLATION BY ANALOG CIRCUIT
(1992-04-23)
HSIEH, HC
;
CHANG, WT
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電信工程研究所
;
Institute of Communications Engineering
An analogue computation circuit is proposed for image interpolation. This circuit is designed to maximise the smoothness of the interpolated data. With this circuit, high speed interpolation can be easily achieved.
FORMATION OF P(+)N JUNCTIONS BY SI(+)+B(+) IMPLANTATION AND LASER ANNEALING
(1992-04-27)
JUANG, MH
;
CHENG, HC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The effects of rapid thermal annealing (RTA) and laser annealing (LA) on the activation and diffusion of ion-implanted boron in Si substrate have been investigated. The implant and anneal regimes, forming good shallow junctions, were presented. The Si+ -preamorphized samples boron implanted with a high dosage showed largely enhanced diffusion in RTA processing. The LA process serves as an excellent scheme to effectively activate the dopant and suppress the anomalous diffusion because of its very high heating rate. A high-quality p+/n junction with a leakage current density lower than 2 nA/cm2 and a forward ideality factor of about 1.01 was formed by laser processing.
ADOPTABILITY AND EFFECTIVENESS OF MICROCODE COMPACTION ALGORITHMS IN SUPERSCALAR PROCESSING
(1992-05-01)
SHIAU, YH
;
CHUNG, CP
;
交大名義發表
;
資訊科學與工程研究所
;
National Chiao Tung University
Superscalar processing is a technique to improve uniprocessor performance by exploiting instruction-level parallelism to issue and execute more than one instruction per clock cycle. To achieve high performance, the instruction sequence must be arranged so that the maximum instruction-level parallelism and hence the minimum execution time are achieved. Microcode compaction is an essential task in the compilation of high-level language programs into microprograms. Four algorithms are widely used in microcode compaction: the first-come-first-served algorithm, critical path algorithm, branch and bound algorithm, and list scheduling algorithm. The objective of this research is to study the adaptability and effectiveness, and to modify the four algorithms so that they can be applied to the instruction scheduling in a basic block of superscalar processor systems to minimize the execution time of a program. Experiments are conducted to examine the adaptability and effectiveness of each algorithm.
WHICH LINEAR TRANSFORMATIONS HAVE ISOMORPHIC HYPERINVARIANT SUBSPACE LATTICES
(1992-05-01)
WU, PY
;
交大名義發表
;
應用數學系
;
National Chiao Tung University
;
Department of Applied Mathematics
Let A be a linear transformation on a finite-dimensional complex vector space with the associated algebra Alg A, commutant {A}', and hyperinvariant subspace lattice Hyperlat A. We determine Alg A, {A}' (up to algebra isomorphism), and Hyperlat A (up to lattice isomorphism) in terms of the parameters in the Jordan form of A.
PHYSICAL MODEL FOR CHARACTERIZING AND SIMULATING A FLOTOX EEPROM DEVICE
(1992-05-01)
WU, CY
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CHEN, CF
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
A physical model has been developed to analyze the dynamic characteristics of a FLOTOX EEPROM device. The effects of the structural parameters such as the area and thickness of the tunneling-oxide and interpoly-oxide layers are characterized by a coupling ratio to describe the discrete programming or erasing operation. The physical parameters including the electron trapping and positive-charge generation effects are used to describe the endurance and retention operations of an EEPROM device. Computer simulations based on this model have been performed to analyze the operations of an EEPROM device, including the effects of three different programming/erasing input voltage waveforms (pulse, exponential rise and triangular). A method for protecting an EEPROM device from overshooting or undershooting during programming or erasing operation is proposed. Therefore, the proposed model can be used as a computer-aided-design (CAD) tool for device design and an efficient simulation tool for describing the dynamic operation and reliability of an EEPROM device.
THE ROLE OF CEMENTED WC SUBSTRATE MORPHOLOGY ON THE DIAMOND FILM GROWTH AND CRACKING RESISTANCE
(1992-05-01)
HUANG, TH
;
KUO, CT
;
LIN, TS
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機械工程學系
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Department of Mechanical Engineering
PHASE-TRANSITION IN AN FE-23.2AL-4.1NI ALLOY
(1992-05-01)
LIU, TF
;
JENG, SC
;
WU, CC
;
機械工程學系
;
材料科學與工程學系
The phase transition in an Fe-23.2 at. pct Al-4.1 at. pct Ni alloy has been investigated by means of transmission electron microscopy. In the as-quenched condition, the microstructure of the alloy is a mixture of (A2 + B2) phases. When the as-quenched alloy is aged at temperatures ranging from 500-degrees-C to 1050-degrees-C, the phase transition sequence is found to be (A2 + B2*) --> (B2 + B2*) --> B2 --> A2, where B2* is also a B2-type phase. It is worthwhile to note that the coexistence of two kinds of ordered B2 phase has not previously been observed by other workers in the Fe-Al-Ni ternary alloy system.
A HARDWARE IMPLEMENTABLE 2-LEVEL PARALLEL COMPUTING ALGORITHM FOR GENERAL MINIMUM-TIME CONTROL
(1992-05-01)
LIN, SY
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交大名義發表
;
電控工程研究所
;
National Chiao Tung University
;
Institute of Electrical and Control Engineering
In this paper, we propose a hardware implementable two-level parallel computing algorithm for general minimum-time control. We first discretize and transform the minimum-time control problem for a continuous-time system into a parameter optimization problem which is large dimensional and nonseparable. Then, the proposed two-level algorithm decomposes this parameter optimization problem into a master-slave problem. The master problem can be easily solved by a one-dimensional gradient method, and the slave problem will be solved by the proposed parallel computing method which combines recursive quadratic programming with the dual method. Furthermore, we have proved the convergence of this iterative two-level parallel computing algorithm under some conditions. Based on the VLSI array processor technology, we present a dedicated hardware computing architecture to realize this algorithm. The corresponding time complexity is also analyzed. Finally, several practical problems including the minimum-time orbit transfer problem and the minimum-time robot control problem have been simulated. The results show that the algorithm is well-suited for real-time application of minimum-time control.
SYNTHESIS OF POLE-ZERO ASSIGNMENT CONTROL LAW WITH MINIMUM CONTROL INPUT
(1992-05-01)
TU, MH
;
LIN, CM
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電控工程研究所
;
Institute of Electrical and Control Engineering
A new method of control system design is developed to simultaneously consider the internal stability, pole assignment, reference signal tracking and control input minimisation. A parametrised design algorithm of the pole-zero assignment control law is derived to achieve the desired goals. The free parameters are used to minimise the L2-norm of the control input signal. Since the requirements of internal stability are satisfied, this design algorithm performs appropriately, even if the plant is unstable and/or is in a nonminimum phase. Examples are given to illustrate the validity of the design algorithm.
THE NOVEL PREPARATION OF P-N-JUNCTION MESA DIODES BY SILICON-WAFER DIRECT BONDING (SDB)
(1992-05-01)
YEH, CF
;
SHYANG, HL
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電控工程研究所
;
光電工程學系
;
Institute of Electrical and Control Engineering
The key processes of silicon-wafer direct bonding (SDB), including hydrophilic surface formation and optimal two-step heat treatment, have been developed However, H2SO4/H2O2 solution being a strong oxidized acid solution, native oxide is found to have grown on the wafer surface as soon as a wafer is treated in this solution. In the case of a wafer further treated in diluted HF solution after hydrophilic surface formation, it is shown that the wafer surface can not only be cleaned of its native oxide but also remains hydrophilic, and can provide excellent voidless bonding. The N+/P and N/P combination junction mesa diodes fabricated on the wafers prepared by these novel SDB technologies are examined. The ideality factor n of the N/P mesa diode is 2.4 approximately 2.8 for the voltage range 0.2 approximately 0.3 V; hence, the lowering of the ideality factor n is evidently achieved. As for the N+/P mesa diode, the ideality factor n shows a value of 1.10 approximately 1.30 for the voltage range 0.2 approximately 0.6 V; the low value of n is attributed to an autodoping phenomenon which has caused the junction interface to form in the P-silicon bulk. However, the fact that the sustaining voltage of the N/P mesa diode showed a value greater than 520 V reveals the effectiveness of our novel SDB processes.
EFFECT OF HYDROGEN ON DEPOSITION OF TANTALUM NITRIDE THIN-FILMS FROM ETHYLIMIDOTANTALUM COMPLEX
(1992-05-01)
CHIU, HT
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CHANG, WP
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交大名義發表
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應用化學系
;
National Chiao Tung University
DETECTION OF CRACKS IN STRUCTURES USING MODAL TEST DATA
(1992-05-01)
KAM, TY
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LEE, TY
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交大名義發表
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機械工程學系
;
National Chiao Tung University
A nondestructive evaluation procedure is presented for identifying a crack in a structure using modal test data. The structure is discretized into a set of elements and the crack is assumed to be located within one of the elements. Measured vibration frequencies and mode shapes are used in an identification process to identify the cracked element based on a simple reduced stiffness model. Static deflection analyses of the structure with and without a crack are performed and a strain energy equilibrium equation is constructed for determining the size of the crack. The detection of a crack on a damaged beam is used to illustrate the applications of the proposed procedure. The present procedure is general and can be easily extended to complex structures with multiple cracks.
SUPERCONFORMAL DEFORMATION, ZERO-NORM STATES AND SPACE-TIME SYMMETRIES OF THE SUPERSTRING THEORIES
(1992-05-01)
LEE, JC
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交大名義發表
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電子物理學系
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National Chiao Tung University
;
Department of Electrophysics
We present a formalism to study type II and Heterotic superstrings with massless and massive background fields in the bosonic sector. This formalism is appropriate to study high energy symmetries of the superstring. As an example, we explicitly relate all massless symmetries to the massless zero-norm states in the spectrum. This includes the E8 x E8 and SO(32) gauge symmetries in the ten-dimensional Heterotic string. The first (even G-parity) massive level is briefly described. We then argue the existence of new symmetries for the massive Yang-Mills-like gauge bosons and tensor fields at each fixed mass level. These enlarged stringy symmetries correspond to the decoupling of massive zero-norm states in the spectrum.