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Recursive Least Squares Estimator with Multiple Exponential Windows in Vector Autoregression

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Acta Mathematicae Applicatae Sinica 2002年第1期18卷 85-102页

作者： hong-zhi An, zhi-guo LiInstitute of Applied Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences,Beijing 100080, ChinaDepartment of Biomathematics, Peking University Health Science Center, Beijing 100083, China Institute of Applied Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China Department of Biomathematics Peking University Health Science Center Beijing China

In the parameter tracking of time-varying systems, the ordinary method is weighted least squares with the rectangular window or the exponential window. In this paper we propose a new kind of sliding window called the multiple exponential window, and then use it to fit time-varying Gaussian vector autoregressive models. The asymptotic bias and covariance of the estimator of the parameter for time-invariant models are also derived. Simulation results show that the multiple exponential windows have better parameter tracking effect than rectangular windows and exponential ones.

关键词： Exponential window rectangular window multiple exponential window weighted least squares method vector autoregression

Factors influencing recovery of left ventricular structure in patients with chronic heart failure

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Chinese Medical Journal 2011年第18期124卷 2868-2873页

作者： DUAN hong-yan WU Xue-si HAN zhi-hong guo Yong-fang FANG Shan-juan ZHANG Xiao-xia WANG Chun-mei Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background Angiotensin converting enzyme （ACE） inhibitors and G-blockers （13B） have beneficial effects on left ventricular （LV） remodeling, alleviate symptoms and reduce morbidity and mortality in patients with chronic heart failure （CHF）. However the correlation between the d osages of ACE inhibitors, βB, and recovery of LV structure remains controversial. Clinical factors associated with recovery of normal ventricular structure in CHF patients receiving medical therapy are poorly defined. Here we aimed to identify variables associated with recovery of normal or near-normal structure in patients with CHF. Methods We recruited 231 consecutive CHF outpatients, left ventricular ejection fraction （LVEF）〈40% and left ventricular end diastolic diameter （LVEDD）〉55/50 mm （male/female）, who were receiving optimal pharmacotherapy between January 2001 and June 2009, and followed them until December 31,2009. They were divided into three groups according to LVEDD and whether they were still alive at final follow-up： group A, LVEDD 〈60/55 mm （male/female）; group B, LVEDD 〉60/55 mm （male/female）; and group C, those who died before final follow-up. Apart from group C, univariate analysis was performed followed by Logistic multivariate analysis to determine the predictors of recovery of LV structure. Results A total of 217 patients completed follow-up, and median follow-up time was 35 months （range 6-108）. Twenty-five patients died during that period; the all-cause mortality rate was 11.5%. Group A showed clinical characteristics as follows： the shortest duration of disease and shortest QRS width, the lowest N-terminal brain natriuretic peptide （NT-proBNP） at baseline, the highest dose of I3B usage, the highest systolic blood pressure （SBP）, diastolic blood pressure （DBP） and the lowest New York Heart Association （NYHA） classification, serum creatinine, uric acid, total bilirubin and NT-proBNP after treatment. Logistic multivariate analysis was performed according to recovery or

关键词： heart failure drug therapy prognosis prognostic factors

THE EFFECT OF KUROSHIO ON THE CIRCULATION IN CHINA SEAS-FROM SATELLITE-TRACKED DRIFTER DATA

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Journal of Hydrodynamics 2003年第4期15卷 109-112页

作者： Hou Yi-jun, Su Jing-zhi, Fang guo-hong, Yin Bao-shu, Cheng Ming-hua Institute of Oceanology, Chinese Acdemy of Sciences, Qingdao 266071, China Institute of Oceanology Chinese Acdemy of Sciences Qingdao 266071 China

A dataset derived from satellite-tracked drifting buoy archived at the Marine Envimoment Data Service (MEDS) in Canada are analyzed to study the effect of the Kuroshio on the China Seas, and the results can exhibit th... 详细信息

关键词： drifter Kuroshio China Seas

基于PETRI网模型的LEO/MEO/GEO三层卫星网络的性能分析

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电子学报 2005年第2期33卷 354-357页

作者：洪志国吴凤鸽范植华李磊孙富春中国科学院软件研究所北京100080 清华大学计算机科学与技术系北京100084

基于Petri网模型方法和仿真方法 ,对一种低轨 /中轨 /同步地球轨 (LEO/MEO/GEO)三层卫星网络进行了性能分析 .首先建立了卫星网络的广义随机Petri网 (GSPN)模型 ,采用SPNP6 .0软件进行了网络性能分析 .然后 ,将分析结果与采用OPNET软件... 详细信息

基于Petri网模型方法和仿真方法 ,对一种低轨 /中轨 /同步地球轨 (LEO/MEO/GEO)三层卫星网络进行了性能分析 .首先建立了卫星网络的广义随机Petri网 (GSPN)模型 ,采用SPNP6 .0软件进行了网络性能分析 .然后 ,将分析结果与采用OPNET软件对该三层卫星网络模拟的结果进行了比较 ,验证了模型的正确性 ,并得出了诸如在高网络负载的情况下三层网络结构的性能优于单层等新的结论 .

关键词：卫星通信 LEO/MEO/GEO卫星网络 GSPN模型性能分析 OPNET

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基于Markov过程的渲染集群可用性分析

通信学报 2011年第4期32卷 166-174页

作者：洪志国王永滨石民勇中国传媒大学计算机学院北京100024 中国传媒大学动画与数字艺术学院北京100024

在考虑到多个集群节点存在着CMF(共模失效)情形下研究了系统的可用性。分别提出了由2个集群节点组成的系统在"单步修复"和"整体修复"方案下的CTMC(连续时间Markov链),得出了2种不同方案的优劣比较结论,同时采用SRN(随机回报网)仿真工具... 详细信息

在考虑到多个集群节点存在着CMF(共模失效)情形下研究了系统的可用性。分别提出了由2个集群节点组成的系统在"单步修复"和"整体修复"方案下的CTMC(连续时间Markov链),得出了2种不同方案的优劣比较结论,同时采用SRN(随机回报网)仿真工具进行了验证;并进一步研讨了n(n>2)个集群节点组成系统的情形。

关键词：渲染共模失效可用性马尔科夫过程

Corrosion Resistance Properties and Preparation of α-C_3N_4 Thin Films

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Wuhan University Journal of Natural Sciences 1999年第2期4卷 52-55页

作者： ZHANG Wei, ZHANG zhi hong, guo Huai xi, XU Yi, FAN Xiang jun Department of Physics, Wuhan University, Wuhan 430072, China

Well adhered C 3N 4 films were prepared by Plasma Enhanced Chemical Vapor Deposition (PECVD) on industrial pure iron substrates using ternary Si N C films as buffer layer. XRD measurement showed that the C 3N 4 films belong to the α C 3N 4 phase. Electrochemical experiments showed that the corrosive resistance of the pure iron raised by two orders of magnitude after being covered with the α C 3N 4 coating.

关键词： carbon nitride corrosion thin film PECVD XRD

Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第01期 26-34页

作者： Yutao Zhang Juan Li Wei-hong Zhu zhiqian guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

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铜矿企业物资采购与管理现状及优化管理措施探析

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价值工程 2018年第17期37卷 107-108页

作者：洪治国铜陵有色金属集团股份有限公司铜山铜矿分公司铜陵244000

对于任何一个企业来讲,内部物资优化管理的重要性都是不言而喻的。企业物资采购管理是对企业运营的整个过程进行的监督、控制和管理。铜矿企业越来越注重物资采购工作。为了进一步加强物资采购工作的管理与控制,铜矿企业建立了内部监控... 详细信息

对于任何一个企业来讲,内部物资优化管理的重要性都是不言而喻的。企业物资采购管理是对企业运营的整个过程进行的监督、控制和管理。铜矿企业越来越注重物资采购工作。为了进一步加强物资采购工作的管理与控制,铜矿企业建立了内部监控机制,对物资采购的工作计划、物资报告审批、采购作业、物资检验到采购结算等各个环节制定了相应的管理标准,以实现企业生产经营的目标。论文从铜矿企业物资采购的具体流程出发,分析了当前铜矿企业物资采购管理中存在的问题,并以此为基础提出了铜矿企业物资采购管理的优化措施。旨在进一步促进铜矿企业各项资金与资源的充分利用,使得铜矿企业发展壮大。

关键词：铜矿企业物资采购管理内部控制

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国有企业物资管理解决方案探析

价值工程 2018年第15期37卷 61-62页

作者：洪治国铜陵有色金属集团股份有限公司铜山铜矿分公司铜陵244000

国有企业的有序运营离不开物资管理这项工作。科学的物资管理有利于企业各项人力与财力资源的充分利用,从而起到降低企业生产管理成本,提高资金流通与周转速度的作用,使得企业在激烈的市场竞争中站稳脚跟并走上可持续发展的道路。不过,... 详细信息

国有企业的有序运营离不开物资管理这项工作。科学的物资管理有利于企业各项人力与财力资源的充分利用,从而起到降低企业生产管理成本,提高资金流通与周转速度的作用,使得企业在激烈的市场竞争中站稳脚跟并走上可持续发展的道路。不过,由于各种因素的综合作用,国有企业物资管理工作中仍然存在很多问题急需改正与完善。为此,论文重点探讨了当前国有企业物资管理工作中的几大难点,在此基础上提出了相应的改善对策,希望能够为业界人士提供一定的参考。

关键词：国有企业物资管理国有资本难点对策