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Stochastic Multi-Symplectic Integrator for Stochastic Nonlinear Schrodinger Equation 被引量:3
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作者 Shanshan Jiang Lijin Wang Jialin Hong 《Communications in Computational Physics》 SCIE 2013年第7期393-411,共19页
In this paper we propose stochastic multi-symplectic conservation law for stochastic Hamiltonian partial differential equations,and develop a stochastic multisymplectic method for numerically solving a kind of stochas... In this paper we propose stochastic multi-symplectic conservation law for stochastic Hamiltonian partial differential equations,and develop a stochastic multisymplectic method for numerically solving a kind of stochastic nonlinear Schrodinger equations.It is shown that the stochasticmulti-symplecticmethod preserves themultisymplectic structure,the discrete charge conservation law,and deduces the recurrence relation of the discrete energy.Numerical experiments are performed to verify the good behaviors of the stochastic multi-symplectic method in cases of both solitary wave and collision. 展开更多
关键词 Stochastic nonlinear Schrodinger equations stochasticmulti-symplectic Hamiltonian systems multi-symplectic integrators
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Novel Multi-Symplectic Integrators for Nonlinear Fourth-Order Schrodinger Equation with Trapped Term 被引量:3
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作者 Jialin Hong Linghua Kong 《Communications in Computational Physics》 SCIE 2010年第3期613-630,共18页
The multi-symplectic Runge-Kutta (MSRK) methods and multi-symplecticFourier spectral (MSFS) methods will be employed to solve the fourth-orderSchrodinger equations with trapped term. Using the idea of split-step numer... The multi-symplectic Runge-Kutta (MSRK) methods and multi-symplecticFourier spectral (MSFS) methods will be employed to solve the fourth-orderSchrodinger equations with trapped term. Using the idea of split-step numericalmethod and the MSRK methods, we devise a new kind of multi-symplectic integrators, which is called split-step multi-symplectic (SSMS) methods. The numerical experiments show that the proposed SSMS methods are more efficient than the conventionalmulti-symplectic integrators with respect to the the numerical accuracy and conservation perserving properties. 展开更多
关键词 Schrodinger equation with trapped term multi-symplectic scheme Fourier spectral method conservation law split-step method
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Multi-symplectic variational integrators for nonlinear Schrdinger equations with variable coefficients
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作者 廖翠萃 崔金超 +1 位作者 梁久祯 丁效华 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期419-427,共9页
In this paper, we propose a variational integrator for nonlinear Schrodinger equations with variable coefficients. It is shown that our variational integrator is naturally multi-symplectic. The discrete multi-symplect... In this paper, we propose a variational integrator for nonlinear Schrodinger equations with variable coefficients. It is shown that our variational integrator is naturally multi-symplectic. The discrete multi-symplectic structure of the integrator is presented by a multi-symplectic form formula that can be derived from the discrete Lagrangian boundary function. As two examples of nonlinear Schrodinger equations with variable coefficients, cubic nonlinear Schrodinger equations and Gross-Pitaevskii equations are extensively studied by the proposed integrator. Our numerical simulations demonstrate that the integrator is capable of preserving the mass, momentum, and energy conservation during time evolutions. Convergence tests are presented to verify that our integrator has second-order accuracy both in time and space. 展开更多
关键词 multi-symplectic form formulas variational integrators conservation laws nonlinear Schr/Sdingerequations
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A LOW-REGULARITY FOURIER INTEGRATOR FOR THE DAVEY-STEWARTSON II SYSTEM WITH ALMOST MASS CONSERVATION
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作者 Cui NING Chenxi HAO Yaohong WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1536-1549,共14页
In this work,we propose a low-regularity Fourier integrator with almost mass conservation to solve the Davey-StewartsonⅡsystem(hyperbolic-elliptic case).Arbitrary order mass convergence could be achieved by the suita... In this work,we propose a low-regularity Fourier integrator with almost mass conservation to solve the Davey-StewartsonⅡsystem(hyperbolic-elliptic case).Arbitrary order mass convergence could be achieved by the suitable addition of correction terms,while keeping the first order accuracy in H~γ×H^(γ+1)for initial data in H^(γ+1)×H^(γ+1)withγ>1.The main theorem is that,up to some fixed time T,there exist constantsτ_(0)and C depending only on T and‖u‖_(L^(∞)((0,T);H^(γ+1)))such that,for any 0<τ≤τ_(0),we have that‖u(t_(n),·)-u^(n)‖H_γ≤C_(τ),‖v(t_(n),·)-v^(n)‖_(Hγ+1)≤C_(τ),where u^(n)and v^(n)denote the numerical solutions at t_(n)=nτ.Moreover,the mass of the numerical solution M(u^(n))satisfies that|M(u^(n))-M(u_0)|≤Cτ~5. 展开更多
关键词 Davey-StewartsonⅡsystem low-regularity exponential integrator first order accuracy mass conservation
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Astrocytes integrate time and space
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作者 Justin Lines 《Neural Regeneration Research》 SCIE CAS 2025年第2期467-468,共2页
Astrocytes read and react to synaptic transmission through tripartite synapses,where the binding of neurotransmitters onto astrocytic receptors triggers an increase in intracellular calcium.Recent investigations have ... Astrocytes read and react to synaptic transmission through tripartite synapses,where the binding of neurotransmitters onto astrocytic receptors triggers an increase in intracellular calcium.Recent investigations have revealed that astrocytes exhibit two distinct states of intracellular calcium activity:(1)graded subcellular localized clusters with independently active microdomains,likely influenced by nearby synaptic events,and(2)whole-cell astrocyte calcium surges,believed to result from the coordinated activation of multiple synapses.Notably,astrocyte calcium responses are not solely graded;instead,a spatial threshold of intracellular calcium activity can be overcome to elicit an astrocyte calcium surge.Together these calcium responses,in turn,initiate downstream signaling pathways capable of modifying synaptic communication and overall network activity.In summary,astrocytes can function as integrators of local synaptic events,actively contributing to information processing within the brain. 展开更多
关键词 GRADED integrATE instead
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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review
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作者 Stiven Roytman Rebecca Paalanen +4 位作者 Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico I.Bohnen 《Neural Regeneration Research》 SCIE CAS 2025年第1期82-92,共11页
Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have ... Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases. 展开更多
关键词 aging BALANCE encephalography functional magnetic resonance imaging GAIT multisensory integration Parkinson’s disease positron emission tomography SOMATOSENSORY VESTIBULAR visual
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Cohort study on the treatment of BRAF V600E mutant metastatic colorectal cancer with integrated Chinese and western medicine
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作者 Jiang-Yu Bian Yu-Fang Feng +1 位作者 Wen-Ting He Tong Zhang 《World Journal of Clinical Oncology》 2025年第1期25-33,共9页
BACKGROUND Patients with BRAF V600E mutant metastatic colorectal cancer(mCRC)have a low incidence rate,poor biological activity,suboptimal response to conventional treatments,and a poor prognosis.In the previous cohor... BACKGROUND Patients with BRAF V600E mutant metastatic colorectal cancer(mCRC)have a low incidence rate,poor biological activity,suboptimal response to conventional treatments,and a poor prognosis.In the previous cohort study on mCRC conducted by our team,it was observed that integrated Chinese and Western medicine treatment could significantly prolong the overall survival(OS)of patients with colorectal cancer.Therefore,we further explored the survival benefits in the population with BRAF V600E mutant mCRC.AIM To evaluate the efficacy of integrated Chinese and Western medicine in the treatment of BRAF V600E mutant metastatic colorectal cancer.METHODS A cohort study was conducted on patients with BRAF V600E mutant metastatic colorectal cancer admitted to Xiyuan Hospital of China Academy of Chinese Medical Sciences and Traditional Chinese Medicine Hospital of Xinjiang Uygur Autonomous Region from January 2016 to December 2022.The patients were divided into two cohorts.RESULTS A total of 34 cases were included,with 23 in Chinese-Western medicine cohort(cohort A)and 11 in Western medicine cohort(cohort B).The median overall survival was 19.9 months in cohort A and 14.2 months in cohort B,with a statistically significant difference(P=0.038,hazard ratio=0.46).The 1-3-year survival rates were 95.65%(22/23),39.13%(9/23),and 26.09%(6/23)in cohort A,and 63.64%(7/11),18.18%(2/11),and 9.09%(1/11)in cohort B,respectively.Subgroup analysis showed statistically significant differences in median OS between the two cohorts in the right colon,liver metastasis,chemotherapy,and first-line treatment subgroups(P<0.05).CONCLUSION Integrated Chinese and Western medicine can prolong the survival and reduce the risk of death in patients with BRAF V600E mutant metastatic colorectal cancer,with more pronounced benefits observed in patients with right colon involvement,liver metastasis,combined chemotherapy,and first-line treatment. 展开更多
关键词 Metastatic colorectal cancer BRAF V600E mutation integrated Chinese and Western medicine Cohort study
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基于Cyber-Integrator语义平台的临床路径工作流管理方法研究 被引量:2
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作者 俞思伟 姜赢 董慧 《医学信息学杂志》 CAS 2010年第9期2-7,共6页
介绍一种基于Cyber-Integrator(CI)语义平台的临床路径(CP)工作流管理方法。阐明国内外语义技术在临床路径应用的成功案例,指出CP语义描述的可行性与不足,深入探讨如何利用CI语义平台来对CP工作流进行管理,包括描述、执行和控制等,说明... 介绍一种基于Cyber-Integrator(CI)语义平台的临床路径(CP)工作流管理方法。阐明国内外语义技术在临床路径应用的成功案例,指出CP语义描述的可行性与不足,深入探讨如何利用CI语义平台来对CP工作流进行管理,包括描述、执行和控制等,说明此方法局限性并提出进一步研究方向。 展开更多
关键词 临床路径 语义技术 Cyber—integrator RDF OWL
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Two New Simple Multi-Symplectic Schemes for the Nonlinear Schrodinger Equation 被引量:5
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作者 王雨顺 李庆宏 宋永忠 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第5期1538-1540,共3页
We investigate the multi-symplectic Euler-box scheme for the nonlinear Schroedinger equation. Two new simple semi-explicit scheme are derived. A composition scheme based on the new derived schemes is also discussed. S... We investigate the multi-symplectic Euler-box scheme for the nonlinear Schroedinger equation. Two new simple semi-explicit scheme are derived. A composition scheme based on the new derived schemes is also discussed. Some numerical results are reported to illustrate the efficiency of the new schemes. 展开更多
关键词 HIGH-ORDER integratorS
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基于ARM Integrator的Sigma-Delta音频DAC的实现
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作者 于芳玲 闫华 钟锐 《电子器件》 CAS 2007年第2期668-671,共4页
介绍了ARM公司的一款FPGA验证开发平台ARMIntegrator,以及基于该平台设计的Sigma-Delta音频DAC的实现.在详细介绍Integrator的各个模块的基础之上,利用开发平台的FPGA上验证实现了一个1阶的6位的Sigma-Delta型的DAC,主要包括Sigma-Delta... 介绍了ARM公司的一款FPGA验证开发平台ARMIntegrator,以及基于该平台设计的Sigma-Delta音频DAC的实现.在详细介绍Integrator的各个模块的基础之上,利用开发平台的FPGA上验证实现了一个1阶的6位的Sigma-Delta型的DAC,主要包括Sigma-Delta DAC的原理与主要电路,FPGA验证实现过程中的DAC数字滤波器以及调制器的设计以及验证流程,通过virsi m仿真时序波形,验证了所设计的DAC正确性和可实现性. 展开更多
关键词 ARM integrator SIGMA-DELTA 插值滤波器 DAC FPGA
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Multi-symplectic method for generalized fifth-order KdV equation 被引量:6
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作者 胡伟鹏 邓子辰 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期3923-3929,共7页
This paper considers the multi-symplectic formulations of the generalized fifth-order KdV equation in Hamiltonian space. Recurring to the midpoint rule, it presents an implicit multi-symplectic scheme with discrete mu... This paper considers the multi-symplectic formulations of the generalized fifth-order KdV equation in Hamiltonian space. Recurring to the midpoint rule, it presents an implicit multi-symplectic scheme with discrete multi-symplectic conservation law to solve the partial differential equations which are derived from the generalized fifth-order KdV equation numerically. The results of the numerical experiments show that this multi-symplectic algorithm is good in accuracy and its long-time numerical behaviour is also perfect. 展开更多
关键词 generalized fifth-order KdV equation multi-symplectic travelling wave solution conservation law
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Geometric formulations and variational integrators of discrete autonomous Birkhoff systems 被引量:5
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作者 刘世兴 刘畅 郭永新 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期284-288,共5页
The variational integrators of autonomous Birkhoff systems are obtained by the discrete variational principle. The geometric structure of the discrete autonomous Birkhoff system is formulated. The discretization of ma... The variational integrators of autonomous Birkhoff systems are obtained by the discrete variational principle. The geometric structure of the discrete autonomous Birkhoff system is formulated. The discretization of mathematical pendulum shows that the discrete variational method is as effective as symplectic scheme for the autonomous Birkhoff systems. 展开更多
关键词 autonomous Birkhoff syetem discrete variational principle variational integrators
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Multi-symplectic methods for membrane free vibration equation 被引量:3
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作者 胡伟鹏 邓子辰 李文成 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第9期1181-1189,共9页
In this paper, the multi-symplectic formulations of the membrane free vibration equation with periodic boundary conditions in Hamilton space are considered. The complex method is introduced and a semi-implicit twenty-... In this paper, the multi-symplectic formulations of the membrane free vibration equation with periodic boundary conditions in Hamilton space are considered. The complex method is introduced and a semi-implicit twenty-seven-points scheme with certain discrete conservation laws-a multi-symplectic conservation law (CLS), a local energy conservation law (ECL) as well as a local momentum conservation law (MCL) --is constructed to discrete the PDEs that are derived from the membrane free vibration equation. The results of the numerical experiments show that the multi-symplectic scheme has excellent long-time numerical behavior, 展开更多
关键词 multi-symplectic complex discretization Runge-Kutta methods
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New explicit multi-symplectic scheme for nonlinear wave equation 被引量:4
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作者 李昊辰 孙建强 秦孟兆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第3期369-380,共12页
Based on splitting multi-symplectic structures, a new multi-symplectic scheme is proposed and applied to a nonlinear wave equation. The explicit multi-symplectic scheme of the nonlinear wave equation is obtained, and ... Based on splitting multi-symplectic structures, a new multi-symplectic scheme is proposed and applied to a nonlinear wave equation. The explicit multi-symplectic scheme of the nonlinear wave equation is obtained, and the corresponding multi-symplectic conservation property is proved. The backward error analysis shows that the explicit multi-symplectic scheme has good accuracy. The sine-Gordon equation and the Klein-Gordon equation are simulated by an explicit multi-symplectic scheme. The numerical results show that the new explicit multi-symplectic scheme can well simulate the solitary wave behaviors of the nonlinear wave equation and approximately preserve the relative energy error of the equation. 展开更多
关键词 nonlinear wave equation multi-symplectic method backward error analysis
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Explicit multi-symplectic method for the Zakharov-Kuznetsov equation 被引量:3
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作者 钱旭 宋松和 +1 位作者 高二 李伟斌 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期43-48,共6页
We propose an explicit multi-symplectic method to solve the two-dimensional Zakharov-Kuznetsov equation. The method combines the multi-symplectic Fourier pseudospectral method for spatial discretization and the Euler ... We propose an explicit multi-symplectic method to solve the two-dimensional Zakharov-Kuznetsov equation. The method combines the multi-symplectic Fourier pseudospectral method for spatial discretization and the Euler method for temporal discretization. It is verified that the proposed method has corresponding discrete multi-symplectic conservation laws. Numerical simulations indicate that the proposed scheme is characterized by excellent conservation. 展开更多
关键词 multi-symplectic method Fourier pseudospectral method Euler method Zakharov-Kuznetsov equation
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Global satisfactory control for nonlinear integrator processes with long delay 被引量:4
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作者 Yiqun YANG Guobo XIANG 《控制理论与应用(英文版)》 EI 2007年第2期207-210,共4页
Integrator processes with long delay are difficult to control. Nonlinear characteristics of actuators make the control problem more challenging. A technique is proposed in this paper for global satisfactory control (... Integrator processes with long delay are difficult to control. Nonlinear characteristics of actuators make the control problem more challenging. A technique is proposed in this paper for global satisfactory control (GSC) of such processes with relay-type nonlinearity. An oscillatory control signal is injected into the nonlinear process; the amplitude and frequency of the oscillatory signal are designed to linearise the nonlinear process in the sense of harmonic analysis; and a state feedback controller is configured to implement GSC over the linearised process. An illustrative example is given to demonstrate the effectiveness of 展开更多
关键词 integrator processes Time delay Oscillation Harmonic linearisation Global satisfactory control
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Multi-symplectic Runge-Kutta methods for Landau-Ginzburg-Higgs equation 被引量:2
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作者 胡伟鹏 邓子辰 +1 位作者 韩松梅 范玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第8期1027-1034,共8页
Nonlinear wave equations have been extensively investigated in the last sev- eral decades. The Landau-Ginzburg-Higgs equation, a typical nonlinear wave equation, is studied in this paper based on the multi-symplectic ... Nonlinear wave equations have been extensively investigated in the last sev- eral decades. The Landau-Ginzburg-Higgs equation, a typical nonlinear wave equation, is studied in this paper based on the multi-symplectic theory in the Hamilton space. The multi-symplectic Runge-Kutta method is reviewed, and a semi-implicit scheme with certain discrete conservation laws is constructed to solve the first-order partial differential equations (PDEs) derived from the Landau-Ginzburg-Higgs equation. The numerical re- sults for the soliton solution of the Landau-Ginzburg-Higgs equation are reported, showing that the multi-symplectic Runge-Kutta method is an efficient algorithm with excellent long-time numerical behaviors. 展开更多
关键词 multi-symplectic Landau-Ginzburg-Higgs equation Runge-Kutta method conservation law soliton solution
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Multi-Symplectic Splitting Method for Two-Dimensional Nonlinear Schrodinger Equation 被引量:2
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作者 陈亚铭 朱华君 宋松和 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期617-622,共6页
Using the idea of splitting numerical methods and the multi-symplectic methods, we propose a multisymplectic splitting (MSS) method to solve the two-dimensional nonlinear Schrodinger equation (2D-NLSE) in this pap... Using the idea of splitting numerical methods and the multi-symplectic methods, we propose a multisymplectic splitting (MSS) method to solve the two-dimensional nonlinear Schrodinger equation (2D-NLSE) in this paper. It is further shown that the method constructed in this way preserve the global symplectieity exactly. Numerical experiments for the plane wave solution and singular solution of the 2D-NLSE show the accuracy and effectiveness of the proposed method. 展开更多
关键词 splitting method multi-symplectic scheme two-dimensional nonlinear SchrSdinger equation
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Design of high-performance energy integrator detector for wideband radar 被引量:2
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作者 CHANG Jiayun FU Xiongjun +1 位作者 JIANG Wen XIE Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1110-1118,共9页
Target detection for wideband radar has recently received extensive attention. The classical energy integrating(EI)detector will always accumulate excess clutter or noise energy,which leads to unacceptable performance... Target detection for wideband radar has recently received extensive attention. The classical energy integrating(EI)detector will always accumulate excess clutter or noise energy,which leads to unacceptable performance deterioration if the detection window is not selected properly. In this paper, an EI detector for the distributed targets in the Gaussian environment is proposed.First, at the stage of preparatory work, the target models are proposed, then, the problem formulation is introduced. Subsequently,in the aspect of optimizing the method of detection window search and the method of threshold setting, the detailed design stages of the proposed detector are provided. Furthermore, theoretical analyses show that the proposed detector is easy to hardware implementation, and it does not need the prior knowledge about the spatial distribution of the target scattering centers in practical radar detection application. Finally, the performance assessment conducted by Monte Carlo simulations verifies that the proposed detector outperforms the conventional detectors. 展开更多
关键词 RADAR detection distributed target integration detec tor.
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Improvement of Boxcar Integrator and Its Application to Low Resistance Measurement of Inductive Load Coil 被引量:2
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作者 Xisheng Li Shaochun Wang(Information Engineering School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1998年第3期180-184,共5页
A boxcar integrator is described which is suitable for the low-repetition-rate signal processing. This boxcar integrator, named fixed-interval mode boxcar integrator, is able to reject harmonics other than the first h... A boxcar integrator is described which is suitable for the low-repetition-rate signal processing. This boxcar integrator, named fixed-interval mode boxcar integrator, is able to reject harmonics other than the first harmonic component. It can also decrease the effective time constant In many situations, the antialiasing filter with narrow bandwidth will cause distortion of the input signal. The fixed-interval mode boxcar integrator with suitable gate width can achieve relative high performance without signal distortion because the bandwidth of its antialiasing filter can be wider than that in the fixed-Point boxcar integrator. ms boxcar integrator is used as majn part of signalprocessing circult in the low resisance measurement of inductive load coil. The results of experiments show that the fixed-interval boxcar integrator is suitable for low-repetition-rate use. 展开更多
关键词 signal processing resistance measurement boxcar integrator
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