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Distributed Localization in Sensor Networks with Noisy Distance Measurements 36

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Distributed Localization in Sensor Networks with Noisy Dista...

第36届中国控制会议

作者： Fei Wu yu-ping tian Bo Wang School of Automation Southeast University

ISBN: (纸本)9781538629185

This paper investigates the distributed localization problem for sensor networks with noisy distance measurements.A distributed iterative algorithm called ECHO-MN is presented based on the signed barycentric coordinate representation,which can be calculated by relative distance *** measurement noise model is presented followed by an unbiased distance estimator which utilizes the past measurement *** advantage of the estimator each sensor node to be located updates its estimates of internode distances and calculates the barycentric coordinate before localization *** attenuate the effect of measurement noise,a gain parameter which decay to zero is used in the *** is proved that ECHOMN converges to the exact location of each sensor almost surely under some necessary *** studies illustrate the proposed localization algorithm.

关键词： Sensor Network Distributed Localization Barycentric Coordinate Measurements Noise

Consensus of discrete-time multi-agent systems with unbounded time-varying delays

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Consensus of discrete-time multi-agent systems with unbounde...

第三十九届中国控制会议

作者： Siheng Zong yu-ping tian School of Automation Southeast University School of Automation Hangzhou Dianzi University

This paper studies the modeling and convergence of discrete-time distributed consensus algorithms with unbounded time-varying delays. Firstly, we reveal that when the consensus algorithm with unbounded time-varying delays is modeled as a time-delay system, the maximum delay in the system equation increases to infinity as time goes on. While this property prevents us from using most tools for convergence analysis of conventional discrete time-delay systems, we study the properties of the system state by building a finite dimensional delay system model in the interval [0, k] for any finite positive integer k. Next, we prove that, under the assumption that the growth rate of the maximum delay is slower than the growth rate of a K∞ class function,and the system topology contains a spanning tree, the consensus algorithm with unbounded time-varying delays can achieve a consensus. And the convergence rate of the algorithm is also characterized. Finally, the simulation experiment demonstrates the correctness of the theoretic result of the paper.

关键词： Time-delay system Consensus Discrete-time system Unbounded time-delay Infinite maximum delay

Consensus analysis of discrete-time multi-agent systems in switching networks: a time-varying Lyapunov function method

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Consensus analysis of discrete-time multi-agent systems in s...

第40届中国控制会议

作者： Bo Wang yu-ping tian Zhimin Han School of Automation Hangzhou Dianzi University

The paper deals with the consensus convergence analysis of discrete-time single-integrator multi-agent systems(MASs) in switching networks. Here, we suppose that the switching network is composed of strongly connected *** adopting a time-varying quadratic Lyapunov function, we give the rigorous proof that the consensus of the single-integrator MASs can be achieved by either a constant-gain protocol or a decaying-gain protocol. This Lyapunov function based consensus analysis method is different from some existed ones for unbalanced switching networks(e.g., the property of products of indecomposable and aperiodic matrices) and provides a new perspective to study the consensus problem of MASs in unbalanced switching networks with uncertainties(e.g., additive noises).

关键词： Multi-agent systems consensus Lyapunov function switching networks

Maximum Allowable Delay Bound for Consensus of General Linear Multi-Agent Systems

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Maximum Allowable Delay Bound for Consensus of General Linea...

第三十一届中国控制会议

作者： Ya Zhang yu-ping tian School of Automation Southeast University Nanjing 210096 China

＜正＞This paper studies the consensus of general linear multi-agent systems with uniform delay and focuses on searching a maximum allowable delay *** fixed and switching topology cases are *** a series of system transformations the consensus problem is converted to the robust stability problem of some uncertain state-delayed *** using Lyapunov-Krasovskii function analysis,consensus conditions which contain the feedback gain condition and delay condition are proposed for systems under fixed topology and switching connected topologies,*** allowable delay bounds are further obtained for both *** long as the delay is less than this bound,there exist linear feedback consensus protocols driving the multi-agent system to achieve *** examples are given to illustrate the results.

关键词： Multi-agent Systems Consensus Delay Switching Topology

姜黄素对慢性脑缺血大鼠脑组织海马CA1区损伤的修复作用及其机制

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中国生物制品学杂志 2011年第10期24卷 1193-1196页

作者：张鹏余天平张雄李昱重庆医科大学神经科学中心重庆400016 重庆市神经生物学重点实验室重庆400016 重庆医科大学病理学教研室重庆400016

目的探讨姜黄素(Curcumin)对慢性脑缺血大鼠脑组织海马CA1区损伤的修复作用及其机制。方法采用双侧颈总动脉永久性结扎建立慢性脑缺血大鼠模型,术后24 h,将模型大鼠随机分为单纯缺血组、姜黄素高剂量(100 mg/kg)治疗组和姜黄素低剂量(50... 详细信息

目的探讨姜黄素(Curcumin)对慢性脑缺血大鼠脑组织海马CA1区损伤的修复作用及其机制。方法采用双侧颈总动脉永久性结扎建立慢性脑缺血大鼠模型,术后24 h,将模型大鼠随机分为单纯缺血组、姜黄素高剂量(100 mg/kg)治疗组和姜黄素低剂量(50 mg/kg)治疗组,另设假手术对照组和正常对照组。姜黄素高、低剂量治疗组分别经腹腔注射100和50 mg/kg姜黄素,单纯缺血组、假手术组和正常对照组腹腔注射等量的DMSO,每天1次,连续14 d。给药14 d后,取各组大鼠脑组织,HE染色和尼氏染色观察海马CA1区的形态学变化,免疫组化法观察海马CA1区神经胶质微丝酸性蛋白(Glial fib-rillaryacidic protein,GFAP)和巢蛋白(Nestin)的表达。结果与假手术组相比,单纯缺血组大鼠海马CA1区锥体细胞和尼氏小体丢失,细胞核固缩,星形胶质细胞肥大并大量增生;经姜黄素治疗后,神经元损伤明显减轻,同时伴有GFAP和Nestin阳性细胞大量增加,姜黄素高剂量治疗组与单纯缺血组相比,差异有统计学意义(P<0.05)。结论姜黄素能显著增强慢性脑缺血大鼠脑组织海马CA1区GFAP和Nestin蛋白的表达,减轻神经元损伤,对慢性脑缺血损伤有一定的治疗作用。

关键词：姜黄素脑缺血神经胶质微丝酸性蛋白巢蛋白

Smooth Exponential Stabilization of Nonholonomic Systems via time-varying feedback

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Smooth Exponential Stabilization of Nonholonomic Systems via...

第十九届中国控制会议

作者： yu-ping tian Shihua Li Department of Automatic Control, Southeast University, Nanjing, 210096, P.R. China

＜正＞The problem of global exponential stabilization of a class of nonholonomic systems via smooth time-varying control is addressed. It is shown that smooth aperiodic time-varying controls for globally exponentially...

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心脏转移性黑色素瘤1例CMR表现特征

四川大学学报（医学版） 2020年第2期51卷 264-266页

作者：岳鹏飞余天平陈玉成孙家瑜四川大学华西临床医学院成都610041 四川大学华西医院病理科成都610041 四川大学华西医院心内科成都610041 四川大学华西医院放射科成都610041

患者,53岁女性,两年前发现"左眼睫状体占位",行"左眼球摘除术",术后病理诊断为恶性黑色素瘤。现因"发现心脏杂音20 d"于我院就诊,结合心脏磁共振(cardiac magnetic resonance, CMR)影像特征(肿物在T1加权与T1加权压脂图像上均表现为高信... 详细信息

患者,53岁女性,两年前发现"左眼睫状体占位",行"左眼球摘除术",术后病理诊断为恶性黑色素瘤。现因"发现心脏杂音20 d"于我院就诊,结合心脏磁共振(cardiac magnetic resonance, CMR)影像特征(肿物在T1加权与T1加权压脂图像上均表现为高信号,提示短T1特征;肿物在T2加权表现为高信号,提示长T2特征;CMR首过灌注显示肿物呈不均匀灌注强化,晚期延迟扫描肿物呈不均匀延迟强化)及PET信号特点,考虑诊断为左眼恶性黑色素瘤心脏转移。此病例提示,多模态CMR心脏影像(T1加权、T2加权、首过灌注、延迟强化、功能电影等)可用于监测和早期发现黑色素瘤心脏转移,对于诊断黑色素瘤的患者建议常规进行心脏彩超筛查,对怀疑存在心脏受累的患者进一步行CMR检查,有助于早期发现并及时干预。

关键词：心脏占位黑色素瘤肿瘤转移心脏磁共振

Coordinated path-following and attitude control for multiple surface vessels via curve extension method

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Coordinated path-following and attitude control for multiple...

第24届中国控制与决策会议

作者： Yang-Yang Chen 1 , yu-ping tian 1 1. School of Automation, Southeast University, Nanjing 210096, China

This paper addresses the problem of coordinated path-following and attitude control design for a group of fully actuated surface vessels on given convex loops. By incorporating the curve extension design with the consensus- based design we propose a solution to the formation and attitude coordination control. It removes the assumption of nonzero total speed of each vessel that is presented in the literature. With the help of invariance-like theorem and the extension of Barbalat’s lemma, it is proved that the designed cooperative control system is asymptotically stable if the bidirectional commutation topology is connected. An simulation example is presented as a proof of concept.

关键词： Fully actuated surface vessels Coordinated path-following Attitude coordination Curve extension Back- stepping

胶质纤维酸性蛋白和巢蛋白在血管性痴呆大鼠海马中的表达

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中国生物制品学杂志 2011年第8期24卷 911-914,920页

作者：余天平张鹏张雄王林辉田茗源李昱重庆医科大学神经科学中心重庆400016 重庆市神经生物学重点实验室重庆400016 重庆医科大学病理学教研室重庆400016

目的观察胶质纤维酸性蛋白(Glial fibrillary acidic protein,GFAP)和巢蛋白(Nestin)在血管性痴呆成年大鼠海马中的表达情况,探讨二者在血管性痴呆疾病中的作用。方法将SD大鼠随机分为假手术组和模型组,模型组经麻醉、永久性双侧颈总动... 详细信息

目的观察胶质纤维酸性蛋白(Glial fibrillary acidic protein,GFAP)和巢蛋白(Nestin)在血管性痴呆成年大鼠海马中的表达情况,探讨二者在血管性痴呆疾病中的作用。方法将SD大鼠随机分为假手术组和模型组,模型组经麻醉、永久性双侧颈总动脉结扎(2VO)建立血管性痴呆大鼠模型,再随机分为术后1、7、14、21和28 d组;假手术组麻醉后只分离双侧颈总动脉而不结扎。不同时间点断颈处死大鼠,取大脑,切片,经苏木素-伊红染色、尼氏染色观察海马神经元的动态变化;免疫组化染色观察GFAP和Nestin在海马区的表达。结果与假手术组相比,模型组术后7 d,海马CA1区和CA3区椎体神经元显著减少,大量胶质细胞增生;术后14、21和28 d,随着脑血流的恢复,椎体神经元的数量逐渐增加,胶质细胞逐渐减少。模型组从术后1 d起,GFAP和Nestin表达即显著增加(P<0.05),GFAP的表达在术后7 d达高峰,Nestin的表达强度比GFAP稍弱一些,在术后14 d达高峰;随着脑血流供应的恢复,在术后21 d和28 d时,Nestin轻微减少,但未完全消失。结论 GFAP和Nestin在血管性痴呆模型大鼠海马中呈动态表达,表明两者在血管性痴呆疾病中可能扮演了保护角色。

关键词：胶质纤维酸性蛋白巢蛋白痴呆,血管性海马