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Detecting Lags in Nonlinear Models Using General Mutual Information

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Journal of Mathematical research and Exposition 2010年第1期30卷 87-98页

作者： wei gao1,2, zheng tian1,3 1. Department of Applied Mathematics, Northwest polytechnical university, Shaanxi 710072, p. r. china 2. school of statistics, xi’an university of finance & economics, Shaanxi 710061, p. r. china 3. National Key Laboratory of pattern recognition, Institute of Automation, Chinese Academy of Sciences, Beijing 100080, p. r. china Department of Applied Mathematics Northwest Polytechnical University Shaanxi P.R.China 710072

The general mutual information （GMI） and general conditional mutual information （GCMI） are considered to measure lag dependences in nonlinear time series. Both of the measures have the property of invariance with transform. The statistics based on GMI and GCMI are estimated using the correlation integral. Under the hypothesis of independent series, the estimators have Gaussian asymptotic distributions. Simulations applied to generated nonlinear series demonstrate that the methods appear to find frequently the correct lags.

关键词： general mutual information general conditional mutual information nonlinear time series lag dependence.

Object registration for remote sensing images using robust kernel pattern vectors

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Science china(Information Sciences) 2012年第11期55卷 2611-2623页

作者： DING MingTao1,JIN Zi2,tian zheng1,3,DUAN xiFa1,ZHAO wei1 & YANG LiJuan1 1Department of Applied Mathematics,Northwest polytechnical university,xi'an 710072,china 2Department of statistics,university of British Columbia,3333-6356 Agricultural road,Vancouver,BC V677 1Z2,Canada 3State Key Laboratory of remote Sensing Science,Institute of remote Sensing Applications,Chinese Academy of Sciences,Bejing 100101,china Department of Applied Mathematics Northwest Polytechnical University Xi’an China Department of statistics University of British Columbia Vancouver Canada State Key Laboratory of remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Bejing China

The registration of multitemperal remote sensing images before and after a disaster is a challenging *** main reason is that there is a dearth of homologous features that can be used as tie points for registration of variform *** paper proposes a new registration method based on robust kernel pattern vector(KpV) for water objects in the remote sensing images,which have complex deformation before and after a *** show how the variform objects can be precisely registered using their robust kernel pattern vectors(rKpVs).The contribution can be divided into three ***,a novel shape descriptor,named as kernel pattern vector(KpV),is ***,a robust kernel principal component analysis(rKpCA) method is proposed,which can not only capture the common pattern of the variform objects but can also act as the Criterion for outlier ***,a registration approach is derived based on the implicit *** demonstrate the power of the proposed approach by comparing it with other existing methods using two real cases:one for lake monitoring in the Jiayu region,and the other for damage mapping of earthquake-induced barrier lake at Tangjiashan(2008 Wenchuan Earthquake).The results show that the method is effective in capturing the common structural pattern of the variform objects before and after a disaster.

关键词： remote sensing image object registration robust kernel pattern vectors(rKpVs) variform object outlier data effective

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概率原则下基于投资者偏好的组合投资选择

系统工程学报 2005年第5期20卷 544-548页

作者：徐金红徐维军李引生西安交通大学管理学院西安交通大学机械学院陕西西安710049

基于理性投资者的基本行为特征,从投资者真实的投资心理出发,给出了概率原则下基于投资者偏好的组合投资选择模型.在该模型中,收益与风险权重大小可以根据投资者对收益与风险的不同偏好程度来确定.对于证券收益率服从任意分布的情形,运... 详细信息

基于理性投资者的基本行为特征,从投资者真实的投资心理出发,给出了概率原则下基于投资者偏好的组合投资选择模型.在该模型中,收益与风险权重大小可以根据投资者对收益与风险的不同偏好程度来确定.对于证券收益率服从任意分布的情形,运用遗传算法的思想设计出了该模型的有效求解算法,并通过Mat-lab语言实现,从而得出投资组合选择.最后,对不同风险偏好下的解进行了数值比较分析.

关键词：概率原则组合投资投资者偏好遗传算法 Matlab语言

基于公路交通协同指数的区域发展协调性评价——以长三角地区为例

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物流工程与管理 2024年第3期46卷 45-50页

作者：孙希莹魏天资刘芮彤高鸿张季一南通大学地理科学学院江苏南通226019 江苏省地质勘查技术院江苏南京210049 南通理工学院商学院江苏南通226001 兰州交通大学测绘与地理信息学院甘肃兰州730070 南通大学南通市空间信息技术研发与应用重点实验室江苏南通226019

交通路网是连接不同经济主体,促进区域经济协调发展的重要基础设施。作为人文地理学和区域经济学研究领域的热点问题之一,在交通路网对社会经济的支撑和带动作用等方面已经积累了大量的研究成果。然而,现有研究聚焦于从区域路网的角度... 详细信息

交通路网是连接不同经济主体,促进区域经济协调发展的重要基础设施。作为人文地理学和区域经济学研究领域的热点问题之一,在交通路网对社会经济的支撑和带动作用等方面已经积累了大量的研究成果。然而,现有研究聚焦于从区域路网的角度分析交通区位优势及其对经济社会发展的影响,较少考虑到不同等级公路在交通效率和通行能力方面的差异及其对区域经济的影响。文中研究了不同等级交通路网密度空间分布格局,提出了基于道路等级和道路密度的长三角区域公路交通协同指数构建方法。以长江三角地区41个城市的交通路网为例,验证文中提出的区域交通协同指数计算方法,并分析了交通协同指数和以GDp为代表的经济统计数据之间的相关性。结果表明,文中提出的区域交通协同指数计算方法可以较好揭示区域内的交通路网空间分布特征,指数计算结果与GDp数据之间呈现显著的正相关性,可以用来反映经济发展趋势。

关键词：公路区域发展协调性评价交通协同指数 GDp

Early brainstem hemorrhage progression:multi-sequence magnetic resonance imaging and histopathology

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Neural regeneration research 2023年第1期18卷 170-175页

作者： xi Guo Jia-Ke Xu xin Qi Yang wei Cheng-wei Wang Hao Li Lu Ma Chao You Meng tian Department of Neurosurgery and Neurosurgery research Laboratory National Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Integrated Traditional and Western Medicine West China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of rehabilitation People’s Hospital of KaramayKaramayXinjiang Uygur Autonomous RegionChina West china Brain research Center West China HospitalSichuan UniversityChengduSichuan ProvinceChina

According to clinical statistics,the mortality of patients with early brainstem hemorrhage is *** this study,we established rat models of brainstem hemorrhage by injecting type Ⅶ collagenase into the right basotegmental pontine and investigated the pathological changes of early brainstem hemorrhage using multi-sequence magnetic resonance imaging and histopathological *** found that brainstem hematoma gradually formed in the injured rats over the first 3 days and then reduced after 7 *** edema that occurred was mainly of the vasogenic *** complete myelin sheath structure was found around the focus of the brainstem *** integrity and continuity of nerve fibers gradually deteriorated over the first 7 *** degeneration was mild in the first 3 days and then obviously aggravated on the 7^(th)*** cytokines,interleukin-1β,and tumor necrosis factorαappeared on the 1st day after intracerebral hemorrhage,reached peak levels on the 3^(rd)day,and decreased from the 7^(th)*** findings show the characteristics of the progression of early brainstem hemorrhage.

关键词： brainstem hemorrhage diffuse tensor imaging diffusion-weighted imaging Fluoro-Jade C staining hematoxylin-eosin staining interleukin-1β luxol fast blue rat model T2-weighted imaging tumor necrosis factor-α

基于主成分分析的天山北坡经济带经济发展评价研究

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数学的实践与认识 2018年第17期48卷 71-78页

作者：王维贤田茂再新疆财经大学统计与信息学院新疆乌鲁木齐830012 中国人民大学应用统计科学研究中心、中国人民大学统计学院北京100872

由于主成分分析是一种实用的多元统计分析方法,具有高阶降维作用,能消除样本指标之间的相关性,在保持样本主要信息的前提下,提取少量具有代表性的主成分,所以近年来在多指标评价上得到越来越广泛的应用.本文采用多元统计中的主成分分析... 详细信息

由于主成分分析是一种实用的多元统计分析方法,具有高阶降维作用,能消除样本指标之间的相关性,在保持样本主要信息的前提下,提取少量具有代表性的主成分,所以近年来在多指标评价上得到越来越广泛的应用.本文采用多元统计中的主成分分析方法对天山北坡经济带内23个市（县）具有代表性的指标进行主成分分析,同时对综合主成分得分给出了排序,并给出了综合评价,提出了相关改进建议.新疆是丝绸之路经济带上的明珠,而天山北坡经济带是新疆经济最发达的地区,在全疆有着举足轻重的影响,由此可见,对其发展进行有效的评价具有重大的实际意义.

关键词：主成分分析天山北坡经济带经济发展水平

长6特低渗油藏剩余油分布主控因素定量化研究

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石油化工应用 2024年第9期43卷 74-79,88页

作者：高卓林刘成何甜张道亮王祎婷张伟霍焱彬邓盼盼延长油田股份有限公司勘探开发技术研究中心陕西延安716000 西安石油大学经济管理学院陕西西安710000 延长油田股份有限公司宝塔采油厂陕西延安716000

依据钻井、测井、生产开发数据,将区内的小层、砂体、油层进行精细划分与对比,对油层进行精细识别,采用定性分析和定量计算、静动态分析相结合的方法,对全区低幅度构造发育程度、沉积相的发育稳定程度、储层性质的变化程度与油层单井平... 详细信息

依据钻井、测井、生产开发数据,将区内的小层、砂体、油层进行精细划分与对比,对油层进行精细识别,采用定性分析和定量计算、静动态分析相结合的方法,对全区低幅度构造发育程度、沉积相的发育稳定程度、储层性质的变化程度与油层单井平均原始含油饱和度、单井平均原始地质储量、单井平均剩余油饱和度、单井平均采出程度、单井平均产量、变异系数等相关地质开发参数进行定量分析统计。研究表明,低幅度构造组合单元的变化对采出程度的影响差值达到1.12%,差值率达到17.1%,单井平均累产差值达到17.3 t,差值率达到0.7%;沉积相变化的快慢对采出程度的影响差值达到0.80%,差值率达到13.7%,单井平均累产差值达到544.3 t,差值率达到23.3%;储层性质变化的快慢对采出程度的影响差值达到1.83%,差值率达到29.5%,单井平均累产差值达到670.4 t,差值率达到26.3%;开发过程中平均原始含油饱和度经过多年开发的变化率,构造的影响差值变化率为0.48%,沉积的影响差值变化率为1.00%,储层性质的影响差值变化率为1.46%。综上分析,储层性质的变化对剩余油的分布具有明显的控制作用,其次为沉积发育变化,最后为构造的变化。

关键词：长6油藏剩余油定量研究主控因素子长油区

长江保护与发展近30年基本态势、面临挑战与协同治理

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长江流域资源与环境 2022年第8期31卷 1653-1663页

作者：杨桂山徐昔保王维中国科学院南京地理与湖泊研究所江苏南京210008 中国科学院大学南京学院江苏南京211100 南京邮电大学地理与生物信息学院江苏南京210003

长江保护与发展一直是地理学、水文学、生态学、区域经济学和环境科学等多学科关注和研究的热点。借助近30年社会经济统计与水文、水环境监测数据及相关专题研究基础数据,客观分析了近30年长江保护与发展的基本态势及面临的主要挑战,并... 详细信息

长江保护与发展一直是地理学、水文学、生态学、区域经济学和环境科学等多学科关注和研究的热点。借助近30年社会经济统计与水文、水环境监测数据及相关专题研究基础数据,客观分析了近30年长江保护与发展的基本态势及面临的主要挑战,并提出促进长江保护与发展协同的政策建议。研究表明:(1)长江流域近30年经济总量不断扩大,在全国地位显著提升,区域发展差距基本稳定,城镇化水平持续提高,居民收入快速增加;(2)生态保护体系基本建立,污染物排放总量控制与区域协调发展取得一定成效,而节能降耗与一体化发展水平亟待提高;(3)长江保护与发展主要面临权衡矛盾日益凸显,产业发展与空间布局缺乏统筹,水环境、水生态与水灾害问题突出,管理缺乏有效的协同等4个方面的挑战;(4)建议从利益相关方共同协商的流域综合管理决策机制、统一的环境保护监管执法和风险应急管理体系、多层级生态保护和空间开发管控机制、市场化双向补偿为核心的生态补偿制度等4个维度构建协同长江保护与发展的流域综合管理机制。

关键词：长江保护基本态势挑战协同治理

High expression of protein phosphatase 2 regulatory subunit B''alpha predicts poor outcome in hepatocellular carcinoma patients after liver transplantation

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World Journal of Gastrointestinal Oncology 2021年第7期13卷 716-731页

作者： Jia-Jia He Lei Shang Qun-wei Yu Ning Jiao Shuang Qiu wei-xiong Zhu Dong-Feng Wu Yun-Er tian Qing Zhang Clinical College of General Hospital of Chinese people's Armed police Force Anhui Medical UniversityHefei 230032AnhuiChina Department of Organ Transplantation The Third Medical Center of Chinese PLA General HospitalBeijing 100039China Department of Health statistics Fourth Military Medical UniversityXi'an 710032Shanxi ProvinceChina Department of Ophthalmology The Third Medical Center of Chinese PLA General HospitalBeijing 100039China

BACKGrOUND protein phosphatase 2 regulatory subunit B''alpha(ppp2r3A)gene has been reported in other tumors,but the influence of ppp2r3A gene expression on the occurrence,development,and prognosis of hepatocellular carcinoma(HCC)remains *** To investigate whether the ppp2r3A gene could be used to predict tumor recurrence and survival of HCC patients after liver transplantation(LT).METHODS Diseased liver tissues of HCC patients after LT were collected as well as their clinical data and follow-up *** immunohistochemical method was used to detect the expression of ppp2r3A protein in the tissues of 108 patients with primary liver ***χ2 test was used to analyze the relationship between ppp2r3A protein expression levels and the clinicopathological features of *** Kaplan-Meier method was used to analyze overall postoperative *** COX proportional hazard model was used to analyze adverse prognostic *** Immunohistochemistry showed that the ppp2r3A protein was mainly expressed in the cytoplasm of HCC *** to corresponding peritumoral tissues,expression was higher in HCC tissues(p≤0.001).Correlation analysis showed that high ppp2r3A expression was correlated with preoperative serum alphafetoprotein(AFp)levels(p=0.003),tumor-node-metastasis-t stage(p≤0.001),and envelope invasion(p=0.001).Univariate analysis showed that overall survival(p≤0.001)and recurrence-free survival(p=0.025)of patients with high ppp2r3A expression(≥4 points)were poor compared to those with low expression(points).The overall survival rates or recurrence-free survival rates at 1,2,and 3 years with high ppp2r3A expression were 73%,38%,and 23%or 31%,23%,and 23%,*** analysis showed that high ppp2r3A expression(hazard ratio=2.900,95%confidence interval:1.411–5.960,p=0.004)was an independent survival risk factor of HCC patients after LT,and it was also an independent predictor of postoperative tumor *** study als

关键词： protein phosphatase 2 regulatory subunit B''α Hepatocellular carcinoma Liver transplantation prognosis Alpha-fetoprotein