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Context-Based Moving Object Trajectory Uncertainty Reduction and Ranking in Road Network

Journal of Computer Science & Technology 2016年第1期31卷 167-184页

作者： Jian dai Zhi-Ming Ding Jia-jie Xu School of Computer Science Beijing University of Technology Beijing 100124 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Software Chinese Academy of Sciences Beijing 100190 China School of Computer Science and Technology Soochow University Suzhou 215000 China

To support a large amount of GPS data generated from various moving objects, the back-end servers usually store low-sampling-rate trajectories. Therefore, no precise position information can be obtained directly from the back-end servers and uncertainty is an inherent characteristic of the spatio-temporal data. How to deal with the uncertainty thus becomes a basic and challenging problem. A lot of researches have been rigidly conducted on the uncertainty of a moving object itself and isolated from the context where it is derived. However, we discover that the uncertainty of moving objects can be efficiently reduced and effectively ranked using the context-aware information. In this paper, we focus on context- aware information and propose an integrated framework, Context-Based Uncertainty Reduction and Ranking （CURR）, to reduce and rank the uncertainty of trajectories. Specifically, given two consecutive samplings, we aim to infer and rank the possible trajectories in accordance with the information extracted from context. Since some context-aware information can be used to reduce the uncertainty while some context-aware information can be used to rank the uncertainty, to leverage them accordingly, CURR naturally consists of two stages： reduction stage and ranking stage which complement each other. We also implement a prototype system to validate the effectiveness of our solution. Extensive experiments are conducted and the evaluation results demonstrate the efficiency and high accuracy of CURR.

关键词： moving object trajectory uncertainty reduction road network context-aware information

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山东省寿光市蔬菜种植区土壤原生动物研究

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山东农业科学 2009年第10期41卷 83-85页

作者：马丽丽郭卫华贺同利庞绪贵战金成代杰瑞山东胜利股份有限公司山东济南250101 山东大学生命科学学院生物多样性与生态学研究所山东济南250100 山东省地质调查院山东济南250013

采用三级十倍环式稀释法,对山东省寿光市郊区土壤中原生动物丰度进行了分析,研究了土壤类型、含水量、无机元素、重金属元素与原生动物丰度的关系。结果表明,土壤原生动物丰度与含水量的变化呈正相关,与总氮、总磷、总硫、总氟含量的变... 详细信息

采用三级十倍环式稀释法,对山东省寿光市郊区土壤中原生动物丰度进行了分析,研究了土壤类型、含水量、无机元素、重金属元素与原生动物丰度的关系。结果表明,土壤原生动物丰度与含水量的变化呈正相关,与总氮、总磷、总硫、总氟含量的变化呈负相关,与大多数重金属元素含量呈负相关。

关键词：山东寿光蔬菜种植区土壤原生动物多样性土壤生态学

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山东省黄河下游地区浅层地下水地球化学特征与环境质量评价

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山东国土资源 2007年第5期23卷 1-5页

作者：庞绪贵战金成滕兆令郑晓梅王增辉代杰瑞山东省地质调查院山东济南250013 五莲县国土资源局山东五莲262300

浅层地下水调查是山东省黄河下游流域生态地球化学调查项目中的一项工作内容。调查是按每16 km2采集1件浅层地下水样品的密度,分析测试As,Ba,Be,Ca,Cd,Co,Cu,Fe,Hg,Pb,Se,Zn,F-,Cl-,Cr6+,NO2-,COD,pH等33项指标;通过对这些指标在浅层地... 详细信息

浅层地下水调查是山东省黄河下游流域生态地球化学调查项目中的一项工作内容。调查是按每16 km2采集1件浅层地下水样品的密度,分析测试As,Ba,Be,Ca,Cd,Co,Cu,Fe,Hg,Pb,Se,Zn,F-,Cl-,Cr6+,NO2-,COD,pH等33项指标;通过对这些指标在浅层地下水中的背景变化规律研究认为:调查区内浅层地下水中各指标含量起伏变化大,局部富集程度高,特别是As,Fe,K,La,Sb,Sn,Zn,Cl-,NO2-等指标的变异系数均>3.0,说明这些指标在浅层地下水中分布极不均匀,虽然背景含量较低,但在局部地段会形成高含量区,影响浅层地下水质量。选择As,Ba,Be,Cd,Co,Cu,Fe,Hg,Mn,Mo,Ni,Pb,Se,Zn,F-,Cl-,Cr6+,NO2-,COD,pH等20项指标,按《地下水环境质量标准》中的要求,对浅层地下水环境质量进行的单项组分和综合评价结果显示,达到较好级以上者不足9%,而较差和极差级者达90%以上,表明调查区内浅层地下水环境污染状况较为严重。

关键词：黄河下游地球化学背景值浅层地下水环境质量综合评价山东省

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Sampling informative context nodes for network embedding

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Science China(Information Sciences) 2021年第11期64卷 120-130页

作者： Danhao ZHU Xin-Yu dai Jiajun CHEN jie YIN Department of Computer Science and Technology Nanjing University Library Jiangsu Police Institute

Several modern network embedding methods learn vector representations from sampled context nodes. The sampling strategies are often carefully designed and controlled by specific parameters that enable them to adapt to different networks. However, the following fundamental question remains: what is the key factor that causes some sampling context results to yield better vectors than others on a certain network? We attempted to answer the question from the perspective of information theory. First, we defined the weighted entropy of the sampled context matrix, which denotes the amount of information it takes. We discovered that context matrices with higher weighted entropy generally produce better vectors. Second, we proposed maximum weighted entropy sampling methods for sampling more informative context nodes; thus, it can be used to produce more informative vectors. Herein, the results of the extensive experiments on the link prediction and node classification tasks confirm the effectiveness of the proposed methods.

关键词： network embedding representation learning random walk entropy weighted entropy

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Synthesis of Well-defined Poly(tetrahydrofuran)-b-Poly(a-amino acid)s via Cationic Ring-opening Polymerization (ROP) of Tetrahydrofuran and Nucleophilic ROP of N-thiocarboxyanhydrides

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Chinese Journal of Polymer Science 2021年第6期39卷 702-708,I0006页

作者： Peng Zhou Xuan-Geng dai jie Kong Jun Ling Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi'an 710072China

The synthesis of block copolymers of poly(tetrahydrofuran)-b-poly(α-amino acid)(PTHF-b-PAA)is challenging since it is difficult to combine the two blocks produced via different/conflicting ring-opening polymerization(ROP)*** this contribution,the cationic ROP of THF is catalyzed by rare-earth triflate[RE(OTf)3]and terminated by 2-(t-butyloxycarbonyl-amino)ethanol(BAE).After the deprotection of t-butyloxycarbonyl(Boc)group,the chain end of PTHF is quantitatively changed to amino group which thereafter initiates the nucleophilic ROP ofα-amino acid N-thiocarboxyanhydrides(NTAs).Both polymerizations are well controlled,generating PTHF and PAA segments with designable molecular weights(MWs).PTHF-b-polylysine(PTHF-b-PLys)and PTHF-b-polysarcosine(PTHF-b-PSar)are obtained with MWs between 8.6 and 28.7 kg/*** above amphiphilic diblock copolymers form micelles in ***40-b-PSar32 acts as a surfactant to stabilize oil-in-water *** segments of PTHF-b-PAA are biocompatible and promising in the biomedical application.

关键词： anhydride polymerization carbonyl

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Self-nucleation Effect of Crystallization with Various Nucleating Agents

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Chinese Journal of Polymer Science 2023年第12期41卷 1912-1920,I0009页

作者： dai Zhang rui-Jun Zhao Gui-Qiu Ma Zhe Ma Tianjin Key Laboratory of Composite and Functional Materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

In this work,the self-nucleation effect on crystallization was studied for polypropylene with various nucleating *** talc was employed to accelerate crystallization of monoclinic α-crystallites,while N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide TMB-5 was used to accelerate the crystallization kinetics and also induce formation of trigonal β-*** induce self-nucleation effect,the occurrence criterion was assessed by the transition temperatures from various domains and the available temperature *** importantly,the resulting influences of self-nucleation effect were quantified by the change of crystallization kinetics and the potential polymorphism *** was found that the α-nucleating agents of talc broadened the temperature window for inducing Domain Ⅱ by elevating the transition temperature from Domain Ⅰ to Domain Ⅱ.Although β-nucleating agent(β-NA)of N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide TMB-5 elevated cooling crystallization temperature obviously,the temperature window for Domain Ⅱ was *** should be emphasized that in presence of β-NA TMB-5,the self-nucleation effect enhances the crystallization of α-crystallite,which show the competition with β-NA *** last,the ternary PP/talc/TMB-5 blend was prepared with the same amounts of α-NA talc and β-NA TMB-5 and it exhibits a similar self-nucleation effect of crystallization,indicating the dominant role of β-NA TMB-5.

关键词： Crystallization Kinetic Polymorphism

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Data-driven iterative learning trajectory tracking control for wheeled mobile robot under constraint of velocity saturation

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IET Cyber-Systems and Robotics 2023年第2期5卷 37-47页

作者： Xiaodong Bu Xisheng dai rui Hou The School of Automation Guangxi University of Science and TechnologyLiuzhouChina The Department of Automation College of Mechatronics Engineering and AutomationShanghai UniversityShanghaiChina The School of Electrical Engineering&Automation Henan Polytechnic UniversityJiaozuoChina

Considering the wheeled mobile robot(WMR)tracking problem with velocity saturation,we developed a data‐driven iterative learning double loop control method with ***,the authors designed an outer loop controller to provide virtual velocity for the inner loop according to the position and pose tracking error of the WMR kinematic ***,the authors employed dynamic linearisation to transform the dynamic model into an online data‐driven model along the iterative *** on the measured input and output data of the dynamic model,the authors identified the parameters of the inner loop *** authors considered the velocity saturation constraints;we adjusted the output velocity of the WMR online,providing effective solutions to the problem of velocity saltation and the saturation constraint in the tracking ***,the inner loop controller only uses the output data and input of the dynamic model,which not only enables the reliable control of WMR trajectory tracking,but also avoids the influence of inaccurate model identification processes on the tracking *** authors analysed the algorithm's convergence in theory,and the results show that the tracking errors of position,angle and velocity can converge to zero in the iterative ***,the authors used a simulation to demonstrate the effectiveness of the algorithm.

关键词： data-driven control dynamic model iterative learning control trajectory tracking velocity saturation wheeled mobile robot

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平阴县浅层地下水地球化学环境质量评价

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山东国土资源 2008年第8期24卷 51-53,56页

作者：庞绪贵王炳华田乃风代杰瑞胡雪平李肖鹏山东省地质调查院山东济南250013 山东省地质测绘院山东济南250013 山东省第八地质矿产勘查院山东日照276800

平阴县浅层地下水调查采样密度为1点/16km2,分析测试27项指标的含量变化规律后,认为调查区浅层地下水中除K,Mn,NO2-等指标含量变化较大,局部富集外,其他指标含量变化小,在浅层地下水中分布较均匀。选择As,Ba,Be,Cd,Co,Cu,Fe,Hg,Mn,Mo,Ni... 详细信息

平阴县浅层地下水调查采样密度为1点/16km2,分析测试27项指标的含量变化规律后,认为调查区浅层地下水中除K,Mn,NO2-等指标含量变化较大,局部富集外,其他指标含量变化小,在浅层地下水中分布较均匀。选择As,Ba,Be,Cd,Co,Cu,Fe,Hg,Mn,Mo,Ni,Pb,Se,Zn,F-,Cl-,Cr6+,NO-2,COD,pH等20项指标,按《地下水质量标准》对浅层地下水环境质量进行的单因子和综合评价,结果显示较好级以上者达88.4%,而较差级仅占11.6%,无极差级分布,调查区内浅层地下水环境质量状况良好。

关键词：地球化学参数质量评价浅层地下水山东平阴

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Variable Separation Solutions in （1＋1）-Dimensional and （3＋1）-Dimensional Systems via Entangled Mapping Approach

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Communications in Theoretical Physics 2006年第3X期46卷 389-392页

作者： dai Chao-Qing YAN Cai-jie ZHANG jie-Fang Department of Information Physics School of Sciences Zhejiang Forestry Univcrsity Lin'an 311300 China Department of Physics Zhejiang Lishui University Lishui 323000 China Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321004 China

In this paper, the entangled mapping approach （EMA） is applied to obtain variable separation solutions of （1＋1）-dimensional and （3＋1）-dimensional systems. By analysis, we firstly find that there also exists a common formula to describe suitable physical fields or potentials for these （1＋1）-dimensional models such as coupled integrable dispersionless （CID） and shallow water wave equations. Moreover, we find that the variable separation solution of the （3＋1）-dimensional Burgers system satisfies the completely same form as the universal quantity U1 in （2＋1）-dimensional systems. The only difference is that the function q is a solution of a constraint equation and p is an arbitrary function of three independent variables.

关键词： entangled mapping approach (1+1)-dimensional systems (3+1)-dimensional Burgers system

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Exact Travelling Solutions of Discrete sine-Gordon Equation via Extended Tanh-Function Approach

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Communications in Theoretical Physics 2006年第1X期46卷 23-27页

作者： dai Chao-Qing ZHANG jie-Fang Department of Information Physics School of Sciences Zhejiang Forestry University Lin'an 311300 China Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321004 China

In this paper, we generalize the extended tanh-function approach, which was used to find new exact travelling wave solutions of nonlinear partial differential equations or coupled nonlinear partial differential equations, to nonlinear differential-difference equations. As illustration, two series of exact travelling wave solutions of the discrete sine-Gordon equation are obtained by means of the extended tanh-function approach.

关键词： discrete sine-Gordon equation exact travelling wave solution extended tanh-function approach

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