Showing papers by "Southeast University published in 1992"
TL;DR: It is shown theoretically that for an arbitrary T-element training set with t(t=/
Abstract: It is shown theoretically that for an arbitrary T-element training set with t(tlT) different inputs, the backpropagation error surface does not have suboptimal local minima if the network is capable of exactly implementing an arbitrary training set consisting of t different patterns As a special case, the error surface of a backpropagation network with one hidden layer and t-1 hidden units has no local minima, if the network is trained by an arbitrary T-element set with t different inputs
114 citations
TL;DR: In this paper, it was shown that if there exists a reversible function g(t) such that g(f(t)) is band-limited, then f (t) can be uniquely determined in terms of its samples f(nT/sub s/) sampled with the Nyquist rate of g( f(t)).
Abstract: It is shown, for an arbitrary function f(t), that if there exists a reversible function g(t) such that g(f(t)) is band-limited, then f(t) can be uniquely determined in terms of its samples f(nT/sub s/) sampled with the Nyquist rate of g(f(t)). The application of this result to undersampling is illustrated by examples. >
110 citations
TL;DR: In this article, the authors examined some properties of the states a+mS(ξ)| 0 > (ξ = reiθ), which are engendered by excitations on a squeezed vacuum state.
64 citations
TL;DR: In this article, the bias-eliminated least squares (BELS) method is applied to unbiased identification of a general class of dynamic errors-in-variables (EV) models where input noise is white noise and output noise is correlated noise.
Abstract: Dynamic errors-in-variables (EV) models are a new type of linear system models and have found extensive practical applications. One common and important concern with EV models is how to remove noise-induced bias in parameter estimators. In this paper some significant extensions to the newly established bias-eliminated least-squares (BELS) method are made, so that this BELS method can be applied to unbiased identification of a general class of dynamic EV models where input noise is white noise and output noise is correlated noise but the noise statistics are unknown a priori. Though still based on the bias correction principle, this method is very meaningful in that it presents a novel and efficient way of utilizing signal-processing techniques to draw much more useful information from sampled data in order to get desirable identification results. The performance of the proposed method is illustrated by numerical examples.
32 citations
TL;DR: A fast and simple algorithm for calculating 3D moments is proposed, using the Pascal triangle transform to calculate monomials with one variable and a powerful systolic structure for implementing the PTT with additions only is proposed.
30 citations
TL;DR: In this paper, an immunosensor based on TIRF principle for monitoring antibody-antigen reactions at solution-quartz interface was developed, where the human IgG (as antigen) was immobilized on the surface of a planar quartz waveguide.
Abstract: An immunosensor based on TIRF principle for monitoring antibody-antigen reactions at solution-quartz interface was developed. The human IgG (as antigen) was immobilized on the surface of a planar quartz waveguide. Binding of FITC labelled goat anti-human IgG from solution to the immobilized antigen was detected, and non-bound signal, non-specific and specific binding singals were distinguished. Four dissociation solutions were used to invwtigate the regeneration of the solid phase p r e tein by monitoring the Ag-Ab dissociation. The immuno-competitive assay was described, which showed the dynamic detecting range could be adjusted. The sensitivity of the sensor system was also given.
29 citations
TL;DR: A new approach, based on the waveform relaxation technique and fast Walsh transform, is first presented for the analysis of lossy coupled transmission lines (LCTL) with arbitrary terminal networks.
Abstract: A new approach, based on the waveform relaxation technique and fast Walsh transform, is first presented for the analysis of lossy coupled transmission lines (LCTL) with arbitrary terminal networks. The simulation accuracy of the new method can be greatly improved, the disadvantage which always exists in previous methods [1]–[7] can be avoided and a considerable saving in time and memory of CPU is obtained.
29 citations
17 Sep 1992
TL;DR: The authors propose a multilayer-feedforward-network-based machine state identification method, and represent certain fuzzy relationships between the fault symptoms and causes with high nonlinearity between the input and the output of the network.
Abstract: The authors propose a multilayer-feedforward-network-based machine state identification method, and represent certain fuzzy relationships between the fault symptoms and causes with high nonlinearity between the input and the output of the network. As a practical diagnosis example, the rolling bearing diagnosis problem has been studied. By collecting the vibration signals of its operation and using the diagnosis model, one can make a decision about the fault causes and fault degree. Simulation experiments have shown that the proposed diagnosis method achieves better performance consisting in high correct classification rate and good flexibility. >
17 citations
14 Jun 1992
TL;DR: The preliminary experimental results obtained are satisfactory, which shows that the FSDFMLP can perform more efficiently than the conventional least mean square based decision feedback filter in the presence of multipath fading of channels with non-Gaussian interferences.
Abstract: The authors describe a fractionally spaced decision feedback multilayer perceptron (FSDFMLP) for adaptive multilevel quadrature amplitude modulation digital mobile radio reception that can overcome the performance degradations due to multipath fading of channels and reject cochannel interference and additive white Gaussian noise simultaneously. The two-ray model is used for the frequency selective fading channel. A fast adaptive learning algorithm called the mixed gradient based fast learning algorithm with variable learning gain and selective updates was used to train the FSDFMLP. The preliminary experimental results obtained are satisfactory, which shows that the FSDFMLP can perform more efficiently than the conventional least mean square based decision feedback filter in the presence of multipath fading of channels with non-Gaussian interferences. >
16 citations
TL;DR: In this article, the scaling-down of gas-lubricated bearings and their special application in microelectromechanical systems (MEMS) was proposed, where a gas bearing could eliminate the friction problem in microactuators and micromotors because its rubbing surfaces are completely separated by a film of gas.
Abstract: This paper proposes the scaling-down of gas-lubricated bearings and their special application in microelectromechanical systems (MEMS). A gas bearing could eliminate the friction problem in microactuators and micromotors because its rubbing surfaces are completely separated by a film of gas. Two kinds of microbearings, the aerodynamic spiral-grooved type and an externally pressurized type, have been designed and fabricated by processes derived from IC fabrication processes. They have been used in micromotors with a rotor diameter of 160 μm and a hub diameter of 48 μm.
16 citations
23 Mar 1992
TL;DR: Experimental results indicate that the CNNDFF can simultaneously overcome the performance degradations due to multipath fading of channels and reject the non-Gaussian cochannel interferences efficiently.
Abstract: The concept of a complex neuron and its model are described. The complex neural-network-based adaptive decision feedback filter (CNNDFF) for M-QAM digital communication reception systems is put forward. The fast adaptive learning algorithm, called mixed-gradient-based fast learning algorithm with variable learning gain and selective updates, is adopted to train the CNNDFF. Experimental results indicate that the CNNDFF can simultaneously overcome the performance degradations due to multipath fading of channels and reject the non-Gaussian cochannel interferences efficiently. By using the fast learning algorithm, improved convergence and tracking ability can be obtained for the CNNDFF with moderate computational complexity. >
24 Jun 1992
TL;DR: A modified steepest descent method is developed for finding the optimal solution and its convergence is proved and an analog circuit based on neural network is proposed for the realization of this method.
Abstract: Time-varying nonlinear programming is discussed in this paper. It is a new concept concerning optimization for time-dependent function. Taking into consideration the time-variation of the time-dependent function, a modified steepest descent method is developed for finding the optimal solution and its convergence is proved. An analog circuit based on neural network is proposed for the realization of this method. This is attractive from the viewpoint of real-time application.
TL;DR: A rapid high-precision measurement of distorted power is described, based on digital filtering techniques, and it is demonstrated that the sampling algorithm using the window leads to significant savings in measuring and computing time, and high accuracy can be obtained.
Abstract: A rapid high-precision measurement of distorted power is described. The measurement is based on digital filtering techniques. The convergence conditions of two previous sampling algorithms are derived, and their frequency responses are analyzed. An adjustable window used for measuring distorted power is also proposed. It is demonstrated that the sampling algorithm using the window leads to significant savings in measuring and computing time, and high accuracy can be obtained. >
30 Aug 1992
TL;DR: The authors present the application of the local moments method to range image segmentation and show that it can segment range images effectively.
Abstract: Shows that the filter-based methods and facet-model-based methods widely used in image analysis and computer vision can be unified by the local moments method, which reveals the relation between these methods and thus extends application of local moments to edge detection, optic flow calculation and range image segmentation, etc. A fast algorithm to calculate local moments is proposed. Finally, the authors present the application of the method to range image segmentation and show that it can segment range images effectively. >
TL;DR: In this paper, the surface structures of lecithin Langmuir-Blodgett monolayers are directly observed by scanning tunneling microscopy (STM), and a possible alignment mechanism is proposed based on the STM results.
TL;DR: In this article, the generation of ultrafine cadmium sulfide particles through exposing poly-(pentacosa-10, 12-diynoic acid) (PDA) Langmuir-Blodgett (LB) films to hydrogen sulfide gas was studied.
TL;DR: In this article, three wave equation tomography algorithms using maximum entropy (ME) for geophysical exploration are proposed, and the realized steps of these algorithms are given in the realization steps.
Abstract: In this paper, three wave equation tomography algorithms using maximum entropy (ME) for geophysical exploration are proposed. The first is the Born iterative inversed scattering algorithm using ME in frequency domain (ME-FDBIIS), in which the Green function is fixed; the second is the distorted Born iterative inversed scattering algorithm using ME in frequency domain (ME-FDDBIIS), in which the Green function is changed in every iteration; the third is the time domain Born iterative inverse scattering algorithm using ME (ME-TDBIIS). In these algorithms, the maximum entropy solution of the two-dimensional inversed scattering problem is selected by the ME Cambridge algorithm from all models which fit the observed scattered data. Then, the realized steps of these algorithms are given in the paper. The numerical examples show that these algorithms are very effective to inverse incomplete and noisy field data and the best results are given by ME-TD-BIIS in these three algorithms.
TL;DR: In this article, the Hamiltonian of an n-level atom with n −1 lower levels being almost degenerate interacting with a field through n − 1 m -photon processes, can also be reduced to a standard Jaynes-Cummings model and the time evolution operator for the system and the density operator for this many m-photon laser field are also given.
TL;DR: In this article, a crown ether liquid crystal is spread on the airwater interface to create monolayers and surface pressure area curves show that the phase transition is accompanied by a change of the liquid crystal molecular structure.
01 Jun 1992
TL;DR: In this paper, a design theory for waveguide E-plane inductive strip filters that takes the high-order mode interaction, and the finite thickness of metal with a dielectric substrate underneath into account is described.
Abstract: A design theory is described for waveguide E-plane inductive strip filters that takes the high-order mode interaction, and the finite thickness of metal with a dielectric substrate underneath into account. The main idea was to use superconducting material, instead of metal, in the design of inductive strip insert filters. A design method is introduced for this purpose, and high-T/sub c/ superconducting (HTSC) films serve as perfect conductors. An X-band bandpass filter was fabricated with HTSC materials. The measured results of the HTSC bandpass filter are presented and compared with the CAD-predicted filter performance. >
TL;DR: In this paper, the alignment of a nematic liquid crystal MBBA on dipalmitorylphosphatidylcholine (DPPC) monolayers has been investigated.
Abstract: The alignment of a nematic liquid crystal MBBA on dipalmitorylphosphatidylcholine (DPPC) monolayers has been investigated. The monolayers are prepared using Langmuir-Blodgett techniique. In the liquid-expended state, the monolayers induce homeotropic alignment of liquid crystal molecules. While in the liquid-condensed and the solid-condensed states, the homeotropic alignment disappears. The experimental result is useful to select a suitable aligning layer for fabricating liquid crystal devices.
01 Jun 1992
TL;DR: In this paper, a potentially low-cost realization of a 61 GHz Doppler radar system for speed measurement over the ground is presented, based on an inverted strip dielectric waveguide used for both the oscillator/mixer and an antenna.
Abstract: A potentially low-cost realization of a 61-GHz Doppler radar system for speed measurement over the ground is presented. It is based on an inverted strip dielectric waveguide used for both the oscillator/mixer and an antenna. A simple Gunn element serves as transmitter as well as the self-oscillating mixer. A number of tests confirmed its good performance. The test results are presented. >
TL;DR: It is noted that the implicit way to describe threshold and refractory period is advantageous to adaptive learning in neural networks and that molecular electronics probably provides an effective approach to implementing the above neuron model.
Abstract: A variant of the FitzHugh-Nagumo model is proposed in order to fully make use of the computational properties of intraneuronal dynamics. The mechanisms of threshold and refractory periods resulting from the double dynamical processes are qualitatively studied through computer simulation. The results show that the variant neuron model has the property that its threshold, refractory period and response amplitude are dynamically adjustable. This paper has also discussed some problems relating to collective property, learning and implementation of the neural network based on the neuron model proposed. It is noted that the implicit way to describe threshold and refractory period is advantageous to adaptive learning in neural networks and that molecular electronics probably provides an effective approach to implementing the above neuron model.
12 May 1992
TL;DR: An automated system for measuring electronic noise and performance factors is presented, which gives not only the power spectral density of equivalent input noise voltage and current, but also other performance factors.
Abstract: Most of the noise instruments can only give a noise figure or equivalent input noise at several frequency points or several fixed frequency bands. An automated system for measuring electronic noise and performance factors is presented. The system gives not only the power spectral density of equivalent input noise voltage and current, but also other performance factors. High accuracy of noise measurements is obtained by using a low-noise amplifier and using scanning CW signals to measure transfer functions. The noise measurement and processed data are automatically produced by a personal computer. >
TL;DR: Based on the characteristics analysis for the grinding spark temperature collected by an infrared measuring instrument, a recognition technique to identifying grinding burn under on-line conditions was successfully applied to the mass production of ball bearing races as mentioned in this paper.
Abstract: Grinding burn is one of the most serious problems affecting the surface integrity of components. The majority of existing methods are based on off-line characteristics, for example residual stress, microhardness and metallography in laboratory conditions, and visual methods for identifying the burned colour in the practical situation. So far, there have been few studies successfully applied to on-line conditions. Based on the characteristics analysis for the grinding spark temperature collected by an infrared measuring instrument, this paper presents a recognition technique to identifying grinding burn under on-line conditions. This recognition technique has been successfully applied to the mass production of ball bearing races.
TL;DR: In this paper, the authors extended the method of lines (MoL) to solve the EM wave scattering problems of periodic surfaces with arbitrary profile, and the scattering coefficients of space harmonics of corrugated and sinusoidal surfaces were calculated.
Abstract: In this paper the Method of Lines (MoL) is successfully extended to solve the EM wave scattering problems of periodic surfaces with arbitrary profile. As examples, the scattering coefficients of space harmonics of corrugated and sinusoidal surfaces are calculated. The results are in good agreement with available data from Wirgin and from A.K.Jordan et al. In addition, the results of comb structure are also calculated. The flexibility and less computation of this method make it eligible for analyzing various two-dimensional periodic structures.
18 Aug 1992
TL;DR: In this paper, an intermediate processing level is proposed to control the information issued by low-level procedures, which consists of filtering and combining centerlines and contours in such a way that only the relevant vessels are preserved.
Abstract: The overall scheme aimed at three-dimensional reconstruction of vascular networks from two X-ray projections relies on the efficient detection of vessels in the image frames. The authors describe an intermediate processing level to control the information issued by low-level procedures. Its role consists of filtering and combining centerlines and contours in such a way that only the relevant vessels are preserved. >
TL;DR: In this article, the effects on boiling hysteresis of locally fluidized particles contained in a liquid that serves as a coolant for electronic equipment were investigated and it was shown that locally fluidised particles can diminish boiling hystresis.
Abstract: Experiments have been performed to determine the effects on boiling hysteresis of locally fluidized particles contained in a liquid that serves as coolant for electronic equipment. The results show that locally fluidized particles can diminish boiling hysteresis.
TL;DR: In this article, a mixture of pentacosa-10,12-diynoic acid and copper tetracynoquinodimethane (CuTCNQ) was formed on a pure water surface.
TL;DR: In this paper, the propagation characteristics of the dominant mode in GNRD guide bend are analyzed employing the coupled-mode theory, and the curves of bending loss vs. the groove depth or width, radius of curvature and frequency are given, which caused by the mode conversion of the operatingLSM 11 x mode to the parasiticLSE 11 xmode.
Abstract: In this paper, the propagation characteristics of the dominant mode in GNRD guide bend are analysed employing the coupled-mode theory. The curves of bending loss vs. The groove depth or width, radius of curvature and frequency are given, which caused by the mode conversion of the operatingLSM 11 x mode to the parasiticLSE 11 x mode. It is found that the groove depth has a great influence upon the bending loss than the other parameters. According to the theoretical results, appropriate sizes of groove and radius of curvature should be chosen in designing a GNRD bend structure.