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根据科研需要完成了水声收发试验系统的设计与工程实现,它可实现主动、被动水声信号的产生、发射、接收、处理与显示等功能。其中,主动水声信号的波形及参数可任意设置,被动信号的产生包括实际采集数据和利用模型产生的数据,信号的显示包括时域和频域波形。该系统利用CVI技术完成了系统界面设计和控制,利用DAQ完成了A/D、D/A转化,将低噪声放大器件和FPGA结合完成了低噪声放大和数字滤波,将有源功率放大器件和单片机结合完成了数控功率放大器设计。系统经调试满足设计要求,具有结构简单、效费比高、扩展性好等特点。 相似文献
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有源滤波电路设计总结 总被引:1,自引:0,他引:1
滤波器是一种能使有用信号通过而大幅抑制无用信号的电子装置。在电子电路中常用来进行信号处理、数据传输和抑制噪声等。在运算放大器广泛应用以前滤波电路主要采用无源电子元件--电阻、电容、电感连接而成,由于电感体积大而且笨重导致整个滤波器功能模块体积大而且笨重。本文介绍由集成运算放大器、电阻和电容设计有源滤波器,着重讲解低通、高通、带通滤波电路。 相似文献
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In this work, a detailed mathematical and physical model for calculating the fluidic impedance of an artery is developed. Initially, the model calculates the impedance of a healthy artery, and then, it compares this with the alteration in the impedance of an artery with atherosclerosis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Mehdi Dehghan Behzad Nemati Saray Mehrdad Lakestani 《Mathematical Methods in the Applied Sciences》2014,37(6):894-912
The current paper proposes a technique for the numerical solution of Burgers equations. The method is based on finite difference formula combined with the Galerkin method, which uses the interpolating scaling functions. Several test problems are given, and the numerical results are reported to show the accuracy and efficiency of the new algorithm. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Francesca Guerriero Giovanna Miglionico Filomena Olivito 《European Journal of Operational Research》2014
The paper addresses restaurant revenue management from both a strategic and an operational point of view. Strategic decisions in restaurants are mainly related to defining the most profitable combination of tables that will constitute the restaurant. We propose new formulations of the so-called “Tables Mix Problem” by taking into account several features of the real setting. We compare the proposed models in a computational study showing that restaurants, with the capacity of managing tables as renewable resources and of combining different-sized tables, can improve expected revenue performances. Operational decisions are mainly concerned with the more profitable assignment of tables to customers. Indeed, the “Parties Mix Problem” consists of deciding on accepting or denying a booking request from different groups of customers, with the aim of maximizing the total expected revenue. A dynamic formulation of the “Parties Mix Problem” is presented together with a linear programming approximation, whose solutions can be used to define capacity control policies based on booking limits and bid prices. Computational results compare the proposed policies and show that they lead to higher revenues than the traditional strategies used to support decision makers. 相似文献
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Chun‐Hui Hsiao 《Numerical Methods for Partial Differential Equations》2014,30(2):536-549
This article presents a rational Haar wavelet operational method for solving the inverse Laplace transform problem and improves inherent errors from irrational Haar wavelet. The approach is thus straightforward, rather simple and suitable for computer programming. We define that P is the operational matrix for integration of the orthogonal Haar wavelet. Simultaneously, simplify the formulae of listing table (Chen et al., Journal of The Franklin Institute 303 (1977), 267–284) to a minimum expression and obtain the optimal operation speed. The local property of Haar wavelet is fully applied to shorten the calculation process in the task. The operational method presented in this article owns the advantages of simpler computation as well as broad application. We still can obtain satisfying solution even under large matrix. Moreover, we do not have numerically unstable problems. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 536–549, 2014 相似文献