Browsing by Issue Date, starting with "1996-09-09"

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Rule combination in a fuzzy neural network
(1996-09-09)
Chen, YJ
;
Teng, CC
;
交大名義發表
;
電控工程研究所
;
National Chiao Tung University
In this paper, we present a fuzzy neural network (FNN) to realize the rule reasoning of fuzzy inference systems. The proposed fuzzy neural network can acquire the fuzzy rules by employing the learning capability of neural networks. Moreover, for simplifying the structure of the proposed FNN, the redundant rules and linguistic terms are removed from the FNN by means of a rule combination procedure. A sufficient condition related to rule combination is also given.
High quality epitaxial Si grown by a simple low pressure chemical vapor deposition at 550 degrees C
(1996-09-09)
Chin, A
;
Lin, BC
;
Chen, WJ
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We have designed a simple-hot wall low pressure chemical vapor deposition (LPCVD) system to grow high quality epitaxial Si films from 550 to 900 degrees C. The epitaxial film has been examined by scan electron microscopy for surface morphology, and by x-ray diffraction and cross-sectional transmission electron microscopy for crystallinity. Its quality has been found comparable to that of the substrate. Reduction of moisture and oxygen in the ambient is critical to the success of the growth at low temperatures. A combination of a leak-tight LPCVD reactor, a high flow rate Of 61/min of H-2 purge, and a pre-bake at high temperature of 950 degrees C has been used to achieve the reduction of moisture and oxygen. Degraded films form with increasing full width at half maximum of x-ray diffraction peak when a pre-bake at lower temperature is used. (C) 1996 American Institute of Physics.
High quality epitaxial Si grown by a simple low pressure chemical vapor deposition at 550 degrees C
(1996-09-09)
Chin, A
;
Lin, BC
;
Chen, WJ
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We have designed a simple-hot wall low pressure chemical vapor deposition (LPCVD) system to grow high quality epitaxial Si films from 550 to 900 degrees C. The epitaxial film has been examined by scan electron microscopy for surface morphology, and by x-ray diffraction and cross-sectional transmission electron microscopy for crystallinity. Its quality has been found comparable to that of the substrate. Reduction of moisture and oxygen in the ambient is critical to the success of the growth at low temperatures. A combination of a leak-tight LPCVD reactor, a high flow rate Of 61/min of H-2 purge, and a pre-bake at high temperature of 950 degrees C has been used to achieve the reduction of moisture and oxygen. Degraded films form with increasing full width at half maximum of x-ray diffraction peak when a pre-bake at lower temperature is used. (C) 1996 American Institute of Physics.
Deep level transient spectroscopy depth profile measurements of polycrystalline zinc oxide ceramic
(1996-09-15)
Lee, WI
;
Young, RL
;
Chen, WK
;
交大名義發表
;
友訊交大聯合研發中心
A method is proposed for performing deep level transient spectroscopy depth profile measurements of defects in polycrystalline ZnO. A multilayer-chip ZnO varistor structure is adopted to minimize the number of grains connected in series. It is verified that the distributions of some defects near the ZnO grain boundary are highly nonuniform. Valuable information has been obtained from the measured defect distribution profiles.
Deep level transient spectroscopy depth profile measurements of polycrystalline zinc oxide ceramic
(1996-09-15)
Lee, WI
;
Young, RL
;
Chen, WK
;
電子物理學系
;
Department of Electrophysics
A method is proposed for performing deep level transient spectroscopy depth profile measurements of defects in polycrystalline ZnO. A multilayer-chip ZnO varistor structure is adopted to minimize the number of grains connected in series. It is verified that the distributions of some defects near the ZnO grain boundary are highly nonuniform. Valuable information has been obtained from the measured defect distribution profiles.
Mechanism of nitrogen coimplant for suppressing boron penetration in p(+)-polycrystalline silicon gate of p metal-oxide semiconductor field effect transistor
(1996-09-16)
Chao, TS
;
Liaw, MC
;
Chu, CH
;
Chang, CY
;
Chien, CH
The mechanism of the nitrogen co-implant to suppress the boron penetration in p(+)-polycrystalline silicon gate has been investigated. The nitrogen coimplant with the BF, combines with the boron to form a B-N complex which results in a retardation of boron diffusion. It is found that metal-oxide-silicon capacitors with nitrogen implantation show improved electrical properties. (C) 1996 American Institute of Physics.
Degradation phenomena of multilayer ZnO-glass varistors studied by deep level transient spectroscopy
(1996-09-16)
Wang, YP
;
Lee, WI
;
Tseng, TY
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The degradation of non-Ohmic electrical characteristics of ZnO-glass chip varistors due to high-intensity impulse currents was correlated with the deep trap levels investigated by means of deep level transient spectroscopy. Three electron traps located at 0.11, 0.27, and 0.94 eV below the conduction band were observed for chip varistors before current impulse testing. These trap energy depths of the chip varistors after current impulse testing were found to be almost unchanged, but their trap densities and capture cross sections both decreased. The concentration of the trap at 0.94 eV was decreased and ascribed to oxygen vacancies existing at the grain boundaries of the varistor. The electrical degradation phenomenon of the chip varistors is closely related to the reaction between the trap at 0.94 eV and adsorbed oxygen ions at the grain boundaries. (C) 1996 American Institute of Physics.
Degradation phenomena of multilayer ZnO-glass varistors studied by deep level transient spectroscopy
(1996-09-16)
Wang, YP
;
Lee, WI
;
Tseng, TY
;
電子物理學系
;
電子工程學系及電子研究所
The degradation of non-Ohmic electrical characteristics of ZnO-glass chip varistors due to high-intensity impulse currents was correlated with the deep trap levels investigated by means of deep level transient spectroscopy. Three electron traps located at 0.11, 0.27, and 0.94 eV below the conduction band were observed for chip varistors before current impulse testing. These trap energy depths of the chip varistors after current impulse testing were found to be almost unchanged, but their trap densities and capture cross sections both decreased. The concentration of the trap at 0.94 eV was decreased and ascribed to oxygen vacancies existing at the grain boundaries of the varistor. The electrical degradation phenomenon of the chip varistors is closely related to the reaction between the trap at 0.94 eV and adsorbed oxygen ions at the grain boundaries. (C) 1996 American Institute of Physics.
Mechanism of nitrogen coimplant for suppressing boron penetration in p(+)-polycrystalline silicon gate of p metal-oxide semiconductor field effect transistor
(1996-09-16)
Chao, TS
;
Liaw, MC
;
Chu, CH
;
Chang, CY
;
Chien, CH
The mechanism of the nitrogen co-implant to suppress the boron penetration in p(+)-polycrystalline silicon gate has been investigated. The nitrogen coimplant with the BF, combines with the boron to form a B-N complex which results in a retardation of boron diffusion. It is found that metal-oxide-silicon capacitors with nitrogen implantation show improved electrical properties. (C) 1996 American Institute of Physics.
Analysis of chlorophenoxy acid herbicides by cyclodextrin-modified capillary electrophoresis
(1996-09-20)
Hsieh, YZ
;
Huang, HY
;
交大名義發表
;
應用化學系
;
National Chiao Tung University
In this study, we developed a capillary electrophoresis method involving cyclodextrins to separate seven chlorophenoxy acid herbicides and their enantiomers. The cavity size and the concentration of cyclodextrins heavily influenced the migration time of individual herbicides. The peak resolution also varied with different concentration ratios of cyclodextrins. Adding 4 mM alpha-cyclodextrin and 1 mM beta-cyclodextrin in the buffer was found to produce the optimum experimental condition. The herbicides examined in this study could be successfully separated within 7 min; meanwhile, the two pairs of enantiomers could also be completely resolved. The calibration lines' correlation coefficients for the separation conditions were all above 0.996. The dynamic range of the analysis of seven herbicides was at least two orders, from 1 ppm to 100 ppm. Analyzing the seven herbicides by capillary electrophoresis posed the advantages of a high resolution, high separation efficiency and good reproducibility. By combining with a C-18 disk preconcentration method, the herbicides' detection limits in the environmental water were below 1 ppb.
A new synthetic approach for nonlinear optical chromophores possessing enhanced thermal stability
(1996-09-23)
Shu, CF
;
Tsai, WJ
;
Jen, AKY
;
應用化學系
;
Department of Applied Chemistry
A synthetic strategy for NLO chromophores containing cyclic-locked, conjugated triene segment has been developed. The incorporation of the ethylenic bonds into a 6-membered ring resulted in enhanced thermal stabilities of chromophores. Copyright (C) 1996 Elsevier Science Ltd
Characterizations of deep levels in SnTe-doped GaSb by admittance spectroscopy
(1996-09-23)
Chen, JF
;
Chen, NC
;
Liu, HS
;
交大名義發表
;
電子物理學系
A dominant deep level with an activation energy of 0.23-0.26 eV was observed by admittance spectroscopy for SnTe-doped GaSb layers grown directly on GaAs substrates by molecular beam epitaxy (MBE). The activation energy and capture cross section of the deep level are similar to the levels detected in S-doped and Te-doped GaSb grown by MBE, indicating that this deep level originates either from a native defect or a common impurity in n-type GaSb. The Sb-4/Ga flux ratio was found to affect the Hall mobility and concentration of the deep level in a similar way, with an optimal beam equivalent pressure ratio around 7 obtained for GaSb grown at 550 degrees C, which should correspond to the lowest ratio to maintain a Sb-stabilized surface reconstruction. Analysis of this result suggests that the deep level seen by us is a complex defect. (C) 1996 American Institute of Physics.
A new synthetic approach for nonlinear optical chromophores possessing enhanced thermal stability
(1996-09-23)
Shu, CF
;
Tsai, WJ
;
Jen, AKY
;
應用化學系
;
Department of Applied Chemistry
A synthetic strategy for NLO chromophores containing cyclic-locked, conjugated triene segment has been developed. The incorporation of the ethylenic bonds into a 6-membered ring resulted in enhanced thermal stabilities of chromophores. Copyright (C) 1996 Elsevier Science Ltd
Characterizations of deep levels in SnTe-doped GaSb by admittance spectroscopy
(1996-09-23)
Chen, JF
;
Chen, NC
;
Liu, HS
;
電子物理學系
;
Department of Electrophysics
A dominant deep level with an activation energy of 0.23-0.26 eV was observed by admittance spectroscopy for SnTe-doped GaSb layers grown directly on GaAs substrates by molecular beam epitaxy (MBE). The activation energy and capture cross section of the deep level are similar to the levels detected in S-doped and Te-doped GaSb grown by MBE, indicating that this deep level originates either from a native defect or a common impurity in n-type GaSb. The Sb-4/Ga flux ratio was found to affect the Hall mobility and concentration of the deep level in a similar way, with an optimal beam equivalent pressure ratio around 7 obtained for GaSb grown at 550 degrees C, which should correspond to the lowest ratio to maintain a Sb-stabilized surface reconstruction. Analysis of this result suggests that the deep level seen by us is a complex defect. (C) 1996 American Institute of Physics.
Polymer blends of polyamide-6 and poly(phenylene oxide) compatibilized by styrene-co-glycidyl methacrylate
(1996-09-26)
Chiang, CR
;
Chang, FC
;
應用化學系
;
Department of Applied Chemistry
Incompatible polymer blends between polyamide-6 (PA6) and poly(phenylene oxide) (PPO) have been compatibilized in situ by the styrene-glycidyl methacrylate (SG) reactive copolymers. The epoxy functional groups in SG copolymers can react with the PA6 amine and carboxylic endgroups at interface to form various SG-g-PA6 copolymers. These in situ-formed grafted copolymers tend to anchor along interface to function as compatibilizer of the blends. The styrene and the SG segments of the grafted copolymers are miscible (or near miscible) with PPO; whereas the PA6 segments are structurally identical with PA6 phase. The compatibilized blend, depending on quantity of the compatibilizer addition and the glycidyl methacrylate (GMA) content in the SG copolymer, results in smaller phase domain, higher viscosity, and improved mechanical properties. About 5% GMA is the optimum content in SG copolymer that produces the best compatibilization of the blends. This study demonstrates that SG reactive copolymers can be used effectively in compatibilizing polymer blends of PA6 and PPO. (C) 1996 John Wiley & Sons, Inc.
EBTC: An economical method for searching the threshold of ETC compression
(1996-09-26)
Yang, CY
;
Lin, JC
;
資訊工程學系
;
Department of Computer Science
An economical method for obtaining a nearly-optimal threshold for the block truncation coding (BTC) image compression algorithm is presented. Simulation results show that the PSNR performance of the proposed economic BTC (EBTC) method is very close to that of the optimised BTC (OBTC) algorithm, but EBTC only takes about half the computation time required by the OBTC algorithm.
EBTC: An economical method for searching the threshold of ETC compression
(1996-09-26)
Yang, CY
;
Lin, JC
;
交大名義發表
;
資訊工程學系
;
National Chiao Tung University
An economical method for obtaining a nearly-optimal threshold for the block truncation coding (BTC) image compression algorithm is presented. Simulation results show that the PSNR performance of the proposed economic BTC (EBTC) method is very close to that of the optimised BTC (OBTC) algorithm, but EBTC only takes about half the computation time required by the OBTC algorithm.
Adaptive lattice-form IIR blind equaliser
(1996-09-26)
Ueng, FB
;
交大名義發表
;
電信工程研究所
;
National Chiao Tung University
;
Institute of Communications Engineering
The author describes incorporation of the lattice-form structure in the blind infinite impulse response (IIR) algorithm, based on a cost function which is a modified version of that proposed by Shalvi and Weinstein. The proposed IIR blind equaliser has the advantage of lower complexity; simulation results also indicate that the proposed IIR blind equaliser has a faster convergence rate and a smaller mean square error (MSE).
Synthesis of sulfone-substituted thiophene chromophores for second-order nonlinear optics
(1996-09-30)
Chou, SSP
;
Sun, DJ
;
Huang, JY
;
Yang, PK
;
Lin, HC
A new series of conjugated thiophene compounds 1-4 containing methylsulfonyl and phenylsulfonyl accepters have been synthesized which possess efficient second-order optical nonlinearities, high thermal stability and good transparency for use as nonlinear optical materials. Copyright (C) 1996 Elsevier Science Ltd
A raster-based C program for siting a landfill with optimal compactness
(1996-10-01)
Kao, JJ
;
交大名義發表
;
環境工程研究所
;
National Chiao Tung University
;
Institute of Environmental Engineering
Landfill siting requires performing spatial analyses for various factors to evaluate site suitability. A geographical information system, although capable of effectively manipulating spatial data, lacks the capability to locate an optimal site when compactness and other factors are considered simultaneously. In our previous work, a mixed-integer compactness model was proposed to overcome this difficulty. However, computational time with a conventional mixed-integer programming package for solving the model is time consuming and impractical. Therefore, in this work, a C program is developed, based on a proposed raster-based branch-and-bound algorithm. The program can implement multi-factor analyses for compactness and other siting factors with weights prespecified by the user. An example is provided to demonstrate the effectiveness of the program. Copyright (C) 1996 Elsevier Science Ltd