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面向水泥工厂PCS7控制系统下的报警系统优化方案研究

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水泥工程 2024年第1期 54-58页

作者：刘酉军李元春中国中材国际工程股份有限公司(南京) 江苏南京211100

本论文旨在研究和解决集散控制系统(DCS系统)中报警系统的泛滥问题,使得报警系统的功能严重受限或失效。本文提出了通过对报警系统进行优化和处理来减少报警消息的方法,最重要的是保留对生产过程安全和操作性有关的重要信息,同时减少不... 详细信息

本论文旨在研究和解决集散控制系统(DCS系统)中报警系统的泛滥问题,使得报警系统的功能严重受限或失效。本文提出了通过对报警系统进行优化和处理来减少报警消息的方法,最重要的是保留对生产过程安全和操作性有关的重要信息,同时减少不必要的干扰性信息。通过这种方式,报警消息能够为操作员提供有用的指导,帮助他们更好地应对异常情况,降低事故风险。最后,展示了实施优化方案后的应用效果,并展望了未来智能报警管理系统的发展趋势。

关键词：水泥工厂报警系统集散控制系统系统的功能 DCS系统事故风险优化方案发展趋势

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网电对抗战备器材储备布局物流场模型研究

火力与指挥控制 2024年第2期49卷 108-113,118页

作者：李晓星吴世龙许有武刘有军王昌宝国防科技大学合肥230037

网电对抗战备器材储备布局的科学性、合理性,直接影响制约战时网电对抗维修器材供应,影响网电对抗装备保障的效能。着眼网电对抗战备器材储备布局的目标,立足网电对抗战备器材储备布局的原则,基于物流场理论构建网电对抗战备器材储备布... 详细信息

网电对抗战备器材储备布局的科学性、合理性,直接影响制约战时网电对抗维修器材供应,影响网电对抗装备保障的效能。着眼网电对抗战备器材储备布局的目标,立足网电对抗战备器材储备布局的原则,基于物流场理论构建网电对抗战备器材储备布局模型,并运用线性规划和Matlab进行模型求解,获得网电对抗战备器材储备布局的优化方案。

关键词：物流场网电对抗战备器材储备布局

The Study of the Graft Hemodynamics with Different Instant Patency in Coronary Artery Bypassing Grafting

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Computer Modeling in Engineering & Sciences 2018年第8期116卷 229-245页

作者： Zhou Zhao Boyan Mao youjun liu Haisheng Yang Yu Chen Cardiac Surgery Department Peking University People’s Hospital.11th.Ave.XizhimenBeijingChina. College of Life Science and Bio-engineering Beijing University of Technology.No.100 PingleyuanChaoyang DistrictBeijingChina.

In coronary artery bypass grafting(CABG),graft’s poor instant patency may lead to an abnormal hemodynamic environment in anastomosis,which could further cause graft failure after the *** paper investigates the graft hemodynamics with different instant patency,and explores its effect on graft postoperative *** CABG 0D/3D coupling multi-scale models which used left internal mammary artery(LIMA)and saphenous vein(SVG)as grafts were *** types of grafts were examined in the models,including normal grafts,grafts with competitive flow and grafts with anastomotic *** results indicated that comparing with SVG grafts,there was a greater difference between normal LIMA graft and non-patent LIMA ***,the backflow occurred even in LIMA systolic *** wall shear stress(WSS)in the graft of the competitive flow LIMA model had an appreciable decrease comparing with the normal *** addition,the WSS in the stenosis region of the anastomotic stenosis LIMA model was much higher than its adjacent *** contrast,the WSS distributions in the SVG models were much smoother than in the LIMA *** oscillatory shear index(OSI),there was little difference between normal LIMA and *** when the graft had competitive flow or anastomotic stenosis,much higher OSI occurred in some regions in LIMA than *** are significant differences in hemodynamics between normal grafts and non-patent grafts both in LIMA and *** hemodynamic environment in a normal LIMA is better than that in a normal ***,in the situation of the two types of non-patent grafts,the hemodynamics of SVG is better than LIMA.

关键词： Coronary artery bypass grafting instant patency graft flow hemodynamics multi-scale model

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一种基于无人机的口面天线外场测试方法

舰船电子工程 2024年第2期44卷 161-165页

作者：蔡云龙刘有军宋峰国防科技大学电子对抗学院合肥230031

口面天线辐射场的功率分布是天线应用中应仔细考虑的关键因素,应用无人机在空中对天线辐射功率的分布进行测量是一种较便捷和准确的方法。论文首先研究了口面天线辐射功率的分布,提出一种应用无人机测试的采样点网,研究了无人机在测试... 详细信息

口面天线辐射场的功率分布是天线应用中应仔细考虑的关键因素,应用无人机在空中对天线辐射功率的分布进行测量是一种较便捷和准确的方法。论文首先研究了口面天线辐射功率的分布,提出一种应用无人机测试的采样点网,研究了无人机在测试域中的坐标转换,使用Matlab对基于采样点网数据重构的辐射场分布进行了仿真验证,结果表明方法可行有效。最后对该方法的改进方向作了研究展望。

关键词：口面天线功率分布测试无人机采样点网

不同坡位土壤养分条件对轻木叶片解剖特征及其适应可塑性的影响

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西北农业学报 2024年第9期33卷 1737-1745页

作者：孙建丽吴俊文肖建冬杜官本王文兵刘有军西南林业大学林学院昆明650233 西南林业大学材料与化学工程学院昆明650233 勐腊县勐醒农场责任有限公司云南西双版纳666303

为探究不同土壤养分条件下轻木叶片的适应稳定策略,揭示轻木在生存区域生态系统中的生存策略。以2 a生轻木叶片为研究材料,分析比较不同坡位土壤养分对轻木叶片解剖结构特征的影响。结果表明:绝大多数土壤养分含量随土层深度增加而降低... 详细信息

为探究不同土壤养分条件下轻木叶片的适应稳定策略,揭示轻木在生存区域生态系统中的生存策略。以2 a生轻木叶片为研究材料,分析比较不同坡位土壤养分对轻木叶片解剖结构特征的影响。结果表明:绝大多数土壤养分含量随土层深度增加而降低,并且上坡位土壤养分含量大多高于下坡位。上坡位轻木叶片大多数解剖结构指标的厚度大于下坡位,两个坡位中维管束木质部面积的变异系数和可塑性指数均最高。全钾对轻木叶片解剖结构有极显著影响(P全氮>有机碳>水解氮>速效钾>有效磷>全磷。叶片解剖结构可塑性使得轻木在不同土壤养分条件中形成生存策略,维管束木质部面积所展现的明显可塑性,是轻木产生对土壤养分的关键适应特征。

关键词：土壤养分叶片解剖结构可塑性轻木

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A Fast-Fractional Flow Reserve Simulation Method in A Patient with Coronary Stenosis Based on Resistance Boundary Conditions

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Computer Modeling in Engineering & Sciences 2018年第8期116卷 163-173页

作者： Wenxin Wang Dalin Tang Boyan Mao Bao Li Xi Zhao Jian liu youjun liu College of Life Science and Bioengineering Beijing University of TechnologyNo.100 PingleyuanChaoyang DistrictBeijing100124China. Mathematical Science Worcester Polytechnic InstituteNo.100 Institute RoadWorcester01609MAUS. Shanghai United Imaging Healthcare Co.Ltd.No.2258 Chengbei Rd.Jiading DistrictShanghaiChina. Department of Cardiology Peking University People’s HospitalNo.133 Xizhimen South StreetXicheng DistrictBeijingChina.

Fractional flow reserve(FFR)is the gold standard to identify individual stenosis causing myocardial ischemia in catheter *** purpose of this study is to present a fast simulation method to estimate FFR value of a coronary artery,which can evaluate the performance of vascular stenosis,based on resistance boundary conditions.A patient-specific 3-dimensional(3D)model of the left coronary system with intermediate diameter stenosis was reconstructed based on the CTA *** resistance boundary conditions used to simulate the coronary microcirculation were computed based on anatomical reconstruction of coronary 3D *** study was performed by coupling the 3D coronary tree model with the lumped parameter model(0D model).The flow rate and pressure of coronary tree were calculated in twenty *** addition,the effect of inlet pressure and myocardial mass on FFRss values has been *** results showed that the effect of myocardial mass was greater than the effect of inlet pressure on *** FFRss simulation method can quickly and accurately assess the influence of coronary stenosis in aid clinical diagnosis.

关键词： Computational fluid dynamics fractional flow reserve resistance boundary condition

基于血流动力学效应优化的体外反搏闭环反馈调控研究

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北京生物医学工程 2024年第4期43卷 338-345页

作者：陈明岩刘有军许可李鲍北京工业大学环境与生命学部北京100124 北京大学第三医院北京100191

目的本文旨在实现针对不同的患者个体,以较优的血流动力学效应为目标,实现个性化的体外反搏(enhanced external counterpulsation,EECP)的闭环反馈调控数值模拟。方法通过集中参数模型模拟研究EECP反搏模式对不同的适应症的影响机制,... 详细信息

目的本文旨在实现针对不同的患者个体,以较优的血流动力学效应为目标,实现个性化的体外反搏(enhanced external counterpulsation,EECP)的闭环反馈调控数值模拟。方法通过集中参数模型模拟研究EECP反搏模式对不同的适应症的影响机制,根据PID控制系统的反馈调节原理,将其应用于体外反搏的研究中,把血液循环系统的闭环式0维集中参数模型作为被控对象,用于个性化体外反搏血流动力学仿真。结合体外反搏局部血流动力学效应评价模型为不同适应症(冠心病或脑卒中)患者设定血流动力学效应优化的个性化目标值,根据设定目标值和当前血流动力学指标之间的误差,通过设置适当的增益系数与误差进行运算来调节不同反搏模式(压力幅值或加压时长)使当前血流动力学指标达到设定目标值。结果反搏压力对于冠状动脉血流动力学指标的增加更加明显。加压时长对于脑动脉的血流动力学效应的影响最为显著。因此对于冠心病患者设定优化目标值舒张压/收缩压(D/S),通过反馈调节反搏压力使当前D/S达到设定D/S,最终使它们之间误差e的绝对值降低至0.06(均<5%),并得到此时的压力幅值。对于脑卒中患者设定目标值脑血流量(cerebral blood flow,CBF),调节系统输入加压时长减小误差,控制系统的输出当前CBF达到设定CBF,使误差e的绝对值降低至0.06(均<5%)并得到此时的加压时长。结论数值模拟中血流动力学指标达到优化目标值时应施加的压力幅值和加压时长可为临床体外反搏优化治疗提供理论依据。

关键词：体外反搏血流动力学效应优化 PID控制系统反馈调控数值模拟

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Hemodynamics of Enhanced External Counterpulsation with Different Coronary Stenosis

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Computer Modeling in Engineering & Sciences 2018年第8期116卷 149-162页

作者： Sihan Chen Bao Li Haisheng Yang Jianhang Du Xiaoling Li youjun liu College of Life Science and Bio-engineering Beijing University of TechnologyNo.100 Ping-leyuanChaoyang DistrictBeijing100124China. The Eighth Affiliated Hospital Sun Yat-sen UniversityNo.3025 ShenNan RoadShenZhenGuangDong518033China.

Enhanced external counterpulsation(EECP)is able to treat myocardial ischemia,which is usually caused by coronary artery ***,the underlying mechanisms regarding why this technique is effective in treating myocardial ischemia remains unclear and there is no patient-specific counterpulsation mode for different rates of coronary artery stenosis in *** study sought to investigate the hemodynamic effect of varied coronary artery stenosis rates when using EECP and the necessity of adopting targeted counterpulsation mode to consider different rates of coronary artery *** 3-dimensional(3D)coronary models with different stenosis rates,including 55%(Model 1),65%(Model 2),and 75%(Model 3),were generated,then coupled with a 0-dimensional(0D)lumped parametric model of the blood circulatory *** was applied to the 0D/3D coupled models to study the hemodynamic response of the coronary *** the same counterpulsation mode,the ratio of diastolic blood pressure to systolic blood pressure of 3 models during counterpulsation was 1.4,and the cardiac output and coronary artery flow rate increased *** low wall shear stress(WSS)and high oscillatory shear index(OSI)areas were mainly located at the posterior end of the stenosis and coronary artery ***,with an increase in the rate of coronary artery stenosis,the increased percentage of flow rate through the coronary artery stenosis and area-averaged WSS *** geometric multiscale model in this study can be used to effectively simulate the hemodynamic characteristics of cardiovascular system following the application of *** precise hemodynamic effect of the coronary artery stenosis can be *** was found from the hemodynamic factors that the coronary artery with lower stenosis rate more likely led to better vascular endothelial ***,it is necessary to adopt patient-specific counterpulsation mode accounting for different condition of coro

关键词： Enhanced external counterpulsation coronary artery stenosis geometric multiscale method wall shear stress hemodynamics

NONLINEAR MOTION MECHANICS MODEL OF CURVED BLOOD VESSEL

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Acta Mechanica Solida Sinica 2003年第1期16卷 67-73页

作者： Qiao Aike liu youjun Wu Shigui Xu Xiaohu Zeng Yanjun Medical School Shantou UniversityShantou 515031China College of Mechanical Engineering Beijing University of TechnologyBeijing 100022China

A geometric model of curved blood vessels is established based on some reasonable hypotheses; the nonlinear motion mechanics model of the curved blood vessel is established according to basic mechanics laws. This model includes much more physiological factors. It couples the interaction of blood flow with mechanical factors such as the displacement, deformation, strain and stress etc. of the curved blood vessel. It is of great importance for investigating the circulation rules of the cardiovascular system and the nonlinear pulse wave propagation in curved blood vessels.

关键词： curved blood vessel motion equation mechanics model pulse wave propagation