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Predictive functional control of integrating process based on impulse response

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控制理论与应用（英文版） 2004年第2期2卷 196-200页

作者： BinZHANG PingLI WeidongZHANG DepartmentofAutomation.ShanghaiJingoTongUniversity Shanghai200030China InformationEngineeringFaculty LiaoningUniversityofPetroleum＆ChemicalTechnologyFushunLiaoning113001China

The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of the load disturbance, a novel error compensation method is proposed. Then predictive functional control of integrating process is designed. The method given generates a simple control structure, which can significandy reduce online computation. Furthermore, the tuning of the controller is fairly straightforward. Simulation results indicate that the designed control system is relatively robust to the parameters variation of the process.

关键词： Integrating process Time delay impulse response Predictive functional control (PFC)

Research on the Relationship Between Environmental and Economic Coupling Systems in Bohai Bay Area Based on a Vector Autoregression(VAR)Model

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Journal of Ocean University of China 2024年第2期23卷 557-566页

作者： CAO Huimin WANG Ping ZHANG Surong XU Dongpo TIAN Weijun Key Laboratory of Marine Environment and Ecology Ministry of EducationOcean University of ChinaQingdao 266100China Business School Qingdao UniversityQingdao 266100China

This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,*** on panel data spanning 2011-2020,a vector autoregressive(VAR)model is used to analyze and forecast the short-run and long-run relationships between three industrial structures,pollutant discharge,and economic *** results showed that the environmental index had a long-term cointegration relationship with the industrial structure economic *** capital chemical oxygen demand(PCOD)and per capita ammonia nitrogen(PNH_(3)N)had a positive impact on delta per capita GDP(dPGDP),while per capita solid waste(PSW),the secondary industry rate(SIR)and delta tertiary industry(dTIR)had a negative impact on *** VAR model under this coupling system had stability and *** impulse response results showed that the short-term effect of the coupling system on dPGDP was basically consistent with the Granger causality test *** addition,variance decomposition was used in this study to predict the long-term impact of the coupling system in the next ten periods(i.e.,ten years).It was found that dTIR had a great impact on dPGDP,with a contribution rate as high as 74.35%in the tenth period,followed by the contribution rate of PCOD up to 3.94%,while the long-term contribution rates of PSW,SIR and PNH3N were all less than 1%.The results show that the government should support the development of the tertiary industry to maintain the vitality of economic development and prevent environmental deterioration.

关键词： Bohai Bay area environmental pollution industrial structure cointegration theory VAR model impulse response

Effect of geopolitical risk and economic uncertainty indices on renewable energy

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Geoscience Frontiers 2024年第3期15卷 237-247页

作者： Xin Zhao Kamel Si Mohammed Yaohui Wang PawełSte˛pien Grzegorz Mentel School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbuPR China Faculty of Economics and Management University Ain Temouchent Belhadj BouchaibAlgeria School of Urban and Regional Science Institute of Finance and Economics ResearchShanghai University of Finance and EconomicShanghaiPR China Institute of Economics and Finance University of SzczecinPoland Department of Quantitative Methods Faculty of ManagementRzeszow University of TechnologyRzeszow 35-959Poland

In this study,the relationships between five renewable energy sub-sectors markets and the geopolitical risk(GPR)and economic uncertainty indices(EUI)were examined using daily data from March 30,2012,to April 1,*** cross mapping results show that the renewable energy indices have definite relationships with the GPR and *** renewable energy indices show differences in response directions,speed and trends for a standard information difference impulse from the GPR and the EUI.A positive dynamic conditional correlation between renewable energies and EUI was observed in the first and second waves of the COVID-19 *** contrast,there was a relatively decreased effect for two risk indices during the Russia-Ukraine conflict of February-March *** results show that renewable energy may act as a time-varying hedge against economic uncertainty and GPR owing to its safehaven properties at various ***,building more secure and reliable renewable energy systems can help countries to increase their energy independence,which protects them against the risks of political and economic uncertainty.

关键词： Renewable energy Uncertainty indices impulse response Safe-haven

Time domain dispersion of underwater optical wireless communication

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Chinese Optics Letters 2011年第3期9卷 1-4页

作者：魏巍张晓晖饶炯辉王文博 Department of Weaponry Engineering Naval University of Engineering Fourth Department of the Naval Command

A new method to count the expected value and variance of time dispersion is presented for time dispersion of underwater optical wireless *** of the typically used Gamma distribution,inverseGaussian distribution is suggested for underwater optical impulse response time waveform *** expectation of this method is in good agreement with experimental *** works may include water absorption to the model.

关键词： impulse response Time domain analysis Water absorption Wireless telecommunication systems

Constrained high-order statistical blind deconvolution of spectral data

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Chinese Optics Letters 2005年第9期3卷 552-555页

作者：袁景和胡自强王桂英徐至展 Institute of Science and Technology for Opto-Electron Information Yantai University Yantai 264005 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

A constrained high-order statistical algorithm is proposed to blindly deconvolute the measured spectral data and estimate the response function of the instruments simultaneously. In this algorithm, no priorknowledge is necessary except a proper length of the unit-impulse response. This length can be easily set to be the width of the narrowest spectral line by observing the measured data. The feasibility of this method has been demonstrated exnerimentally by the measured Raman and absorntion snectral data.

关键词： impulse response Mathematical techniques Signal to noise ratio Spectrophotometers Statistical methods

Dynamic denoising studies in wideband radio channel measurement and modeling

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 43-46页

作者： COULIBALY Balla Moussa ZHAO Xiong-wen LIANG Xiao-lin LI Shu LI Yi-wei School of Electrical and Electronic Engineering North China Electric Power University

The fixed level and dynamic denoising method was studied based on indoor-to-outdoor measured channel impulse responses ORs） at 5.25 GHz with radio frequency （RF） 100 MHz bandwidth. It is found that the dynamic ranges, peak powers and noise floors of the IRs are with close correlations. The comparisons with different denoising methods are given by deriving the power delay profiles （PDPs）, root mean square （RMS） delay spread （RMS DS）, number of paths （NOPs） and Ricean K-factors. It is concluded that the traditional fixed level noise cut is under estimate of DS and NOPs. The Ricean K-factors are of little sensitive to noise cut irrespective of what kind of methods applied. The PDPs are not very sensitive to the fixed level noise cut, however, obvious changes can be found by dynamic noise cut. The dynamic noise cut is preferred when clear noise floors is observed and decided from the measured IRs, it＇s of importance in data post processing for wideband radio channel measurements as well as the relevant modeling work.

关键词： impulse response wideband channel denoising channel parameter channel measurement

Multipath dispersion of pulse signals in a non-line-of-sight optical scattering channel

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Chinese Optics Letters 2006年第11期4卷 633-635页

作者：冯涛陈刚方祖捷 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

Multipath-induced pulse broadening in a non-line-of-sight （NLOS） optical scattering channel is investigated. Expressions for impulse response and digital signal-to-noise ratio （DSNR） penalty induced by intersymbol interference （ISI） of a NLOS ultraviolet （UV） scattering communication are introduced based on a single-scattering model, and simulated results for some typical atmospheric condition and configuration of geometry are given in the paper. It is shown that the multipath dispersion is one of the most important factors limiting the system performances, and return-to-zero （RZ） format is more suitable for the optical scattering communications than non-return-to-zero （NRZ） format. The method proposed here can be used to predict available bandwidth and data rate of the communication system operating in a NLOS optical scattering channel. OCIS codes： 060.4510, 290.1310, 060.5530.

关键词： Bandwidth Communication systems impulse response Light scattering Signal to noise ratio

Estimating Primaries by Sparse Inversion with Cost-Effective Computation

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Communications in Computational Physics 2020年第6期28卷 477-497页

作者： Xiaopeng Zhou Yike Liu Lanshu Bai Key Laboratory of Petroleum Resource Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China China Earthquake Networks Center Beijing 100045China

Recently,attenuation of surface-related multiples is implemented by a large-scale sparsity-promoting inversion where the primaries are iteratively estimated without a subtraction process,which is called estimation of primaries by sparse inversion(EPSI).By inverting for surface-free impulse responses,EPSI simultaneously updates the primaries and multiples,both of which contribute to explaining the input data,and therefore promote the global convergence ***,one of the major concerns of EPSI may lie in its high computational *** this paper,based on the same gradient-descent framework with EPSI,we develop a computationally cost-effective primary estimation approach in which a newly defined parameterization of primary-multiple model is adopted and an efficiently defined analytical step-length is *** developed approach can yield a better primary estimation at less computational cost as compared to EPSI,which is verified by two synthetic datasets in numerical ***,we apply this approach to a shallow-water field dataset and achieve a desirable performance.

关键词： Inverse problem multiple removal primary estimation impulse response

A simple algorithm to calculate the pulsed sound field of a wide-band linear phased array

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Journal of Harbin Institute of Technology(New Series) 2006年第4期13卷 427-430页

作者：黄晶阙沛文张志钢雷华明金建华 School of Electronic and Computer Information Engineering Ningbo University of Technology Institute of Automatic Detection Shanghai Jiaotong University

A simple algorithm using an impulse response for a rectangular piston element is discussed. The impulse response of linear phased array is obtained hv stumming the impulse responses of rectangular piston elements with different delay times. The output response of the linear wide-band array is equal to the convolution of impulse response functions with wide-band pulse exeiting signal. Sound field distributions and impulse responses of three kinds of transducers are compared. The results can be used to optimize the parameters of the linear phased array transducers used in uhrasonie imaging in nondestructive testing （NDT）.

关键词： linear phased array ultrasonic transducer impulse response sound field