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On the background of the compilation of a new round MFZ(marine functional zoning) in Tangshan, this paper take the method of integrating onsite survey and remote sensing survey, comprehensively considers the status quo of marine development and utilization, marine natural environment, social needs, economic and technical feasibility, then evaluates the existing natural coastline in Tangshan and defined...
This paper proposes a method of quick and large-capacity output of waveform under condition of limited hardware resource, that is, waveform sequence synthesis method. This method is mainly applied under the condition that the memory space is limited but it is required to carry out repeated output of one or several kinds of complex waveforms with bright features, such as the field of radar system,...
Wavelet analysis based analog circuit fault detecting sensitivity and feature extraction optimization methods are studied. Good localization on time-frequency domain of wavelet transformation provides better feature representation for faulty circuits than unitary time or frequency domain analysis. However, different wavelets express diverse resolution for fault recognition. Root mean square (RMS)...
Diagnosis of incipient faults for analog circuits is very important, yet very difficult. A novel approach for incipient faults in analog circuits is proposed. Firstly, the statistical property feature vector, which is composed of range, mean, standard deviation, skewness, kurtosis, entropy and centroid, is used to reflect the global property of output response. Then, the least squares support vector...
Algorithm of phasor circle model, a fault modeling on complex plane for fault dictionary in time domain analysis of linear analog circuit, is presents. The proposed algorithm achieved to characterize all potential fault status of each component with a circle on complex plane, using a voltage measurement approach on the only output node, and the unified mathematical formula of all complex circle is...
Time-interleaved parallel technology is still the best way to implement a data acquisition system with higher sampling rate. In order to make a system of multiple analog to digital converters (ADCs) achieve an optimal performance, a large number of calibration works should be done on the parameters, such as gain, offset and time error, based on sampled data after ADCs. And it also should get correctly...
The data collected through high densely distributed wireless sensor networks is immense. The asymmetry between the data acquisition and information processing makes a great challenge to the restriction of energy and computation consumption of the sensor nodes, and it limits the application of wireless sensor networks. However, the recent works show that compressed sensing can break through this limitation...
In this paper, a novel condition trend prediction method named WHMAR for electronic systems is presented, which is based on weighed Hidden Markov model (HMM) and autoregressive model(AR). The basic idea is constructing AR prediction cells as the output of HMM, which leads to a segmentation of the time series into different AR models. The hidden state sequence of the Markov chain is chosen and predicted...
In this paper, we propose a specified hardware to analyze network frames and collect protocol information for network faults diagnosis system (NFDS). The hardware has been designed in reconfigurable chips as high speed protocol parsing module (HSPPM), which takes the advantage to implement flexible network protocol stack. In NFDS, only frame header needs to be processed. It is the right task for HSPPM,...
Although the empirical mode decomposition (EMD) is a new time-frequency analysis technique, it has a wide-ranging application in last decade. In this paper, we proposed a combined signal denoising method based on EMD and use the denoising method to recover the corrupted test signal. Three traditional denoising methods are combined with EMD to implement the signal denoising. The simulation validate...
According to traditional glitch capture method, this paper introduces a full-channel and high-speed glitch capture technology based on FPGA, and discusses the implementation method of the detecting circuit. It can take a small cost to realize the performances of detection and improve the flexibility of the design using this technology. It is also very convenient to realize the full-channel glitch...
In many applications of wireless sensor networks, message localization is very important to determine the place where events incur and the position where data come from. We present a new anchor-free overlapped area localization method which divides the target area into a serial of grid cells in a round. The overlapped area of the cells created by different round is used to determine the minimum area...
This thesis discusses a method of high-speed large-capacity data storage used in a digital storage oscilloscope, which is the technology of data storage with different phases. It has achieved the technical indicators of maximum real-time sampling rate of 200MSPS, memory depth of 2M sampling points. The principle and implementation of the technology of data storage with different phases, including...
A triple module redundant turboset emergent trip system (ETS) based on triple modular redundancy fault-tolerance technology is discussed in this paper, which is used for safety protection of large steam turbine. The system consists of input modules, main controllers, bus controllers and output modules, in which the 2-out-of-3 (2oo3) vote mechanism is adopted to enhance the reliability and safety of...
The selection of parameters and structure are critical for wavelet neural networks (WNN) when they are used for fault diagnosis. Genetic algorithm is presented to optimize the structure and the parameters of WNN in the training process because of its good ability of global optimization. This method solves the main problem of easily falling into local extreme minimum to cause slow convergence when...
Parallel power rectifier cabinets can increase the capacity of excitation system while may cause serious current unbalance problems among cabinets or thyristors. In this paper, the design of intelligent current-sharing controller (ICSC) based on infineon micro controller unit (MCU) XC164 and field programmable gate array (FPGA) is discussed in detail. The fuzzy self-adaptive PID control algorithm...
Singularities and irregular structures typically characterize the content of signals. The Lipschitz Exponent (LE) is the most popular measure of the singularity behavior of a signal. Most of the existing methods of measuring LE using wavelet transform are derived from the previous work of Mallat and Hwang in [1], which equals LE to the maximum slope of straight lines that remain above the wavelet...
Test Selection in DFT (design for test) is known to be a NP-complete problem. Applying particle swarm optimization algorithm to test selection is firstly proposed in this paper. By analyzing characteristics of test selection, it constructs particles and velocities of BPSO (binary particle swarm optimization); It optimizes the particles using the fitness, which includes the indexes of test selection,...
A construction of the digital intelligent trigger circuit used in hand-held scopemeter is discussed in this paper. The FIFO (first-in-first-out memory device) and high-speed digital comparator which can be controlled by program are used in system. In this way, the multiple functions of the trigger circuit are achieved
In this study an enhanced operational dataset is used to compute rainfall, surface heat, and moisture fluxes, and vertical profiles of diabatic and/or subgrid-scale heating and moistening over a variety of large-scale arrays for the equatorial west Pacific. The mean budget-derived rainfall ranged from 4 to 12 mm day -1 , with the most rain occurring within the intensive flux array and...
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