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Nuclear Norm Subspace System Identification and Its Application on a Stochastic Model of Plague

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Journal of Systems Science & Complexity 2020年第1期33卷 43-60页

作者： YU Miao LIU Jianchang zhao lichun College of Information Science and Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004China School of Mathematics and Information Science Anshan Normal UniversityAnshan 114007China

The discrete-time model of plague is deduced by zero-order holder based on the continuoustime *** to the existence of stochastic disturbances,the stochastic model is given corresponding to the discrete-time *** state estimation and noise reduction of the stochastic model are achieved by designing Kalman *** norm minimization is to structure the low-rank matrix approximation instead of the singular value decomposition in the process of subspace system *** to the plague data from the World Health Organization,the system matrices and noise intensity of the model are *** are carried out to show the higher approximation capability of the proposed method.

关键词： Kalman filter nuclear norm plague stochastic model subspace identification

ADAPTIVE CONTROLLER AND ITS APPLICATION IN FORCE SYSTEM OF ASYMMETRIC CYLINDER CONTROLLED BY SYMMETRIC VALVE

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 50-53页

作者： WU Zhenshun ZHANG lichun zhao Chunlei School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model reference adaptive controller is designed using equilibrium point stability theory and output error equation polynomial. The reference model is selected in such a way that it meets the system dynamic performance. Hardware configuration of asymmetric cylinder controlled by asymmetric valve hydraulic system is replaced by intelligent control algorithm, thus the cost is lowered and easy to application. Simulation results demonstrate that the proposed adaptive control sheme has good adaptive ability and well solves asymmetric dynamic performance problem. The designed adaptive controller is fairly robust to load disturbance and system parameter variation.

关键词： Asymmetric cylinder controlled by symmetric servo valve Model reference Balance point Adaptive control

BIFURCATION CONTROL OF A PREDATOR-PREY MODEL BASED ON NUTRITION KINETICS

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International Journal of Biomathematics 2013年第4期6卷 1-19页

作者： lichun zhao JINGNA LIU WEI GAO College of Mathematics and Information Science Anshan Normal University Anshan 114005 P. R. China School of Foreign Languages Liaoning University of Science and Technology Anshan 114004 P. R. China

The existence conditions of Hopf bifurcation for a predator prey model based on nutri- tion kinetics are given. The two results may appear as follows： one is that the model has a stable periodic trajectory from Hopf bifurcation, which shows the system is in an eco- logical balance; the other is that periodic trajectory from Hopf bifurcation is unstable, which indicates the system is in a sharp or catastrophic loss of stability. For the latter, a bifurcation controller is designed to make the periodic trajectory stable. Finally, some simulations are carried out to prove the results.

关键词： Nutrition kinetics Hopf bifurcation bifurcation control predator prey model.

Optimal harvest of an interval model of carbon sink fisheries with multi-trophic levels

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International Journal of Biomathematics 2016年第3期9卷 21-38页

作者： Yi Zhang Qiaoling Zhang lichun zhao School of Science Shenyang University of Technology Shenyang 110870 P. R. China Nanjing University of Science and Technology Nanjing 210094 P. R. China College of Mathematics and Information ScienceAnshan Normal University Anshan 114007 P. R. China

Considering the uncertainty of kelp-abalone-sea cucumber population, an interval model of carbon sink fisheries with multi-trophic levels is proposed. The equilibria of the model are identified and the corresponding stabilities are discussed. And the existence of bionomic equilibrium of the model is investigated. Next the optimal controller is designed to obtain the optimal harvest using Pontryagin＇s maximum principle. Numerical simulations are carried to prove the results.

关键词： Carbon sink fisheries multi-trophic levels optimal harvest interval model.

Development of a wheat aphid population dynamics model based on cusp catastrophe theory

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International Journal of Biomathematics 2020年第8期13卷 113-131页

作者： Yuan Li Zhen Li lichun zhao Zuqing Hu Huiyan zhao College of Plant Protection Northwest A&F University YanglingShaanxi 712100P.R.China College of Mathematics and Information Science Anshan Normal University Anshan Liaoning 114005P.R.China

Aphids are a major global wheat,pest that can cause considerable loss of *** of aphid population dynamics is an integral part of management strategies to manage or control aphid *** this paper,first,a wheat aphid population dynamics model was developed based on a logistic model and theⅠlollingⅢfunctional response,which includes three factors:temperature,natural enemies and ***,this model fitted with a cusp catastrophe model to describe how abrupt changes in the wheat aphid population were influenced by these factors,Finally,the system was validated with field data from 2016 to *** bifurcation set of the cusp catastrophe model was deemod to be the quantified dynamic control threshold,so an outbreak of aphid's population can be explained according to the variation of control *** short,this aphid population model was successfully validated on survey data,which can be used to guide the prevention and control of aphids.

关键词： Aphids population dynamics model cusp catastrophe theory functional response

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露天煤矿端帮单车道运输设计研究

露天采矿技术 2024年第1期39卷 92-95页

作者：徐长友刘永杰赵立春国家电投内蒙古能源有限公司内蒙古通辽029200

为了最大限度回采露天煤矿端帮边坡压覆资源,基于极限平衡理论和端帮超前内排技术基本原理,应用SLOPE/W软件分析双车道改单车道运输设计对端帮整体边坡和局部边坡影响,分阶段、岩性研究了单车道循环运输条件下露天煤矿端帮最优边坡形态... 详细信息

为了最大限度回采露天煤矿端帮边坡压覆资源,基于极限平衡理论和端帮超前内排技术基本原理,应用SLOPE/W软件分析双车道改单车道运输设计对端帮整体边坡和局部边坡影响,分阶段、岩性研究了单车道循环运输条件下露天煤矿端帮最优边坡形态。研究结果表明:合理优化单车道循环运输位置,在保证端帮整体和局部边坡稳定情况下,能够显著提高煤炭资源回采率;在不超初步设计情况下,与原研究设计相比,通过优化端帮边坡设计,在实行单车道循环运输基础上,可提高端帮整体边坡角4°,提高端帮局部边坡角5°,可多采出煤炭资源300.4万t;与端帮边坡上双车道运输平盘相比,基于不同阶段端帮边坡单车道设计,可创造经济效益非常显著。

关键词：单车道循环运输平盘宽度刚体极限平衡理论端帮边坡设计经济效益

AECOPD患者血清一氧化氮合酶水平与30 d内因急性加重再入院的关系

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中华危重病急救医学 2024年第7期36卷 712-716页

作者：郭志强刘云峰高晓玲李润杰赵立春河北北方学院附属第一医院急诊科河北张家口075061 河北北方学院附属第一医院高压氧科河北张家口075061 河北北方学院附属第一医院手术室河北张家口075061

目的探讨慢性阻塞性肺疾病急性加重(AECOPD)患者血清一氧化氮合酶(NOS)水平与出院后30 d内因急性加重再入院的关系。方法采用前瞻性队列研究方法,选择2020年1月至2022年12月河北北方学院附属第一医院收治的AECOPD患者作为研究对象。收... 详细信息

目的探讨慢性阻塞性肺疾病急性加重(AECOPD)患者血清一氧化氮合酶(NOS)水平与出院后30 d内因急性加重再入院的关系。方法采用前瞻性队列研究方法,选择2020年1月至2022年12月河北北方学院附属第一医院收治的AECOPD患者作为研究对象。收集患者的性别、年龄、体质量指数(BMI)、慢性阻塞性肺疾病(COPD)病程、吸烟史、基础疾病等一般资料,入院24 h内实验室指标、血清NOS水平〔诱导型一氧化氮合酶(iNOS)、内皮型一氧化氮合酶(eNOS)、神经型一氧化氮合酶(nNOS)〕、急性生理学与慢性健康状况评分Ⅱ(APACHEⅡ)及总住院时间,并记录患者出院后30 d内是否因急性加重再入院。比较30 d内再入院与未再入院患者上述临床指标的差异;采用多因素Logistic回归分析筛选AECOPD患者出院后30 d内再入院的影响因素;绘制受试者工作特征曲线(ROC曲线),分析各项影响因素对再入院的预测价值。结果最终共纳入168例患者,出院后30 d内因急性加重再入院38例,未再入院130例。与未再入院组比较,再入院组患者入院24 h内白细胞计数(WBC)、C-反应蛋白(CRP)、APACHEⅡ评分及血清iNOS、eNOS水平均明显升高〔WBC(×10^(9)/L):14.19(12.88,16.12)比11.81(10.63,14.11),CRP(mg/L):51.41±12.35比40.12±7.79,APACHEⅡ评分(分):22.0(19.0,25.0)比18.0(14.0,20.5),iNOS(μg/L):5.87±1.36比4.52±0.89,eNOS(μg/L):4.40±1.00比3.51±1.08,均P<0.01〕,血红蛋白(Hb)、白蛋白(Alb)水平明显降低〔Hb(g/L):108.82±22.06比123.98±24.26,Alb(g/L):30.28±3.27比33.68±2.76,均P<0.01〕;而两组性别、年龄、BMI、COPD病程、吸烟史、基础疾病、总住院时间及血清nNOS水平差异均无统计学意义。多因素Logistic回归分析显示,CRP〔优势比(OR)=1.201,95%可信区间(95%CI)为1.075~1.341〕、APACHEⅡ评分(OR=1.335,95%CI为1.120~1.590)及血清iNOS(OR=5.496,95%CI为2.143~14.095)、eNOS(OR=3.366,95%CI为1.272~8.090)为AECOPD患者出院后30 d内因急性加重再入院的独立危险因素(均P<0.05),Hb(OR=0.965,95%CI为0.933~0.997)、Alb(OR=0.551,95%CI为0.380~0.799)为保护因素(均P<0.05)。ROC曲线分析显示,血清iNOS、eNOS水平对AECOPD患者出院后30 d内再入院均具有预测价值,ROC曲线下面积(AUC)分别为0.791(95%CI为0.694~0.887)和0.742(95%CI为0.660~0.823);当最佳截断值分别为5.22μg/L和3.82μg/L时,敏感度分别为81.54%和69.23%,特异度分别为71.05%和81.58%。血清iNOS、eNOS水平与Hb、Alb、CRP、APACHEⅡ评分联合预测再入院的AUC可达到0.979(95%CI为0.958~1.000),敏感度为91.54%,特异度为97.37%。结论AECOPD患者血清iNOS、eNOS水平升高与出院后30 d内因急性加重再入院相关;AECOPD患者入院后24 h内联合检测Hb、Alb、CRP及血清iNOS、eNOS水平并评价APACHEⅡ评分能够较好地预测其再入院风险。

关键词：慢性阻塞性肺疾病急性加重再入院诱导型一氧化氮合酶内皮型一氧化氮合酶预测

STABILIZATION OF A KIND OF PREY-PREDATOR MODEL WITH HOLLING FUNCTIONAL RESPONSE

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Journal of Systems Science & Complexity 2006年第3期19卷 436-440页

作者： Xi LIU Qingling ZHANG lichun zhao College of Science Northeastern University Shenyang 110006 China.

The stabilization problem of a kind of prey-predator model with Holling fimctional response is investigated. By approximate linearization approach, a feedback control law stabilizing the closed- loop system is obtained. On the other hand, by exact linearization approach, a suitable change of coordinates in the state space and a feedback control law render the complex nonlinear system to be a linear controllable one such that the positive equilibrium point of the closed-loop system is globally asymptotically stable.

关键词： Approximate linearization asymptotically stable exact linearization prey-predator model state feedback control.

Analysis and control of a non-smooth population model with impulsive effects

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International Journal of Biomathematics 2018年第5期11卷 267-283页

作者： Jing Na Liu Tie Zhang lichun zhao Bing Liu Department of Mathematics Northeastern University Shenyang 110006 P. R. China School of Mathematics and Information Science Anshan Normal University AnShan 114007 P. R. China

In this paper, a non-smooth population model with impulsive effects is proposed by combining discontinuity and non-smoothness. According to the qualitative theory of differential equations, the global analysis of the model is discussed. Using the theory of impulsive differential equations, the existence conditions of order one periodic solution are obtained. And the impulsive controllers are designed to make the pest populations stay at the refuge level. Some simulations are carried out to prove the results.

关键词： Impulsive differential equation global analysis order one periodic solution impulsive controller non-smooth population model.