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Viewpoint Optimization Method for Flying Robot Inspecting Transmission Towers Based on Point Cloud Model

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Chinese Journal of Electronics 2018年第5期27卷 976-984页

作者： liu Chang'an dong Ruifang JIN Lu WU hua School of Control and Computer Engineering North China Electric Power University

This paper presents a method to derive optimal viewpoints for flying robot based transmission tower inspection, which applies point cloud model. A safe envelope is established according to safe transmission tower inspection rules. Essential inspection factors are proposed to evaluate the quality of candidate viewpoints, which includes visibility, dimensionality feature of point cloud as well as the distance between viewpoint and transmission power. A score function is constructed to quantify candidate viewpoints, while multiple attribute decision theory is applied to calculate the weight of each factor. Particle swarm optimization(PSO) is used to find the optimal viewpoints set. Both simulation experiment and practical observations are carried out. The results prove that optimal viewpoints have a great contribution for accurate transmission tower inspection. Final results are compared to patch-based method and proved to be feasible.

关键词： Transmission tower inspection Viewpoint optimization Point cloud model Particle swarm optimization(PSO) Flying robot

Minimizing Resource Cost for Camera Stream Scheduling in Video Data Center

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Journal of Computer Science & Technology 2017年第3期32卷 555-570页

作者： Yi-Hong Gao hua-dong Ma Wu liu Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications Beijing 100876 China

Video surveillance service, which receives live streams from IP cameras and forwards the streams to end users, has become one of the most popular services of video data center. The video data center focuses on minimizing the resource cost during resource provisioning for the service. However, little of the previous work comprehensively considers the bandwidth cost optimization of both upload and forwarding streams, and the capacity of the media server. In this paper, we propose an efficient resource scheduling approach for online multi-camera video forwarding, which tries to optimize the resource sharing of media servers and the networks together. Firstly, we not only provide a fine-grained resource usage model for media servers, but also evaluate the bandwidth cost of both upload and forwarding streams. Without loss of generality, we utilize two resource pricing models with different resource cost functions to evaluate the resource cost： the linear cost function and the non-linear cost functions. Then, we formulate the cost minimization problem as a constrained integer programming problem. For the linear resource cost function, the drift-plus-penalty optimization method is exploited in our approach. For non-linear resource cost functions, the approach employs a heuristic method to reduce both media server cost and bandwidth cost. The experimental results demonstrate that our approach obviously reduces the total resource costs on both media servers and networks simultaneously.

关键词： video data center resource scheduling video surveillance as a service multi-camera networking

Effects of process parameters on surface quality,composition segregation,microstructure and properties of QSn6.5-0.1 alloy slabs fabricated by HCCM horizontal continuous casting

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Journal of Iron and Steel Research International 2017年第3期24卷 273-281页

作者： Yang liu Xin-hua liu hua-dong Fu Min-xuan Lou Jian-xin Xie Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China

Columnar-grained QSn6. 5-0. 1 alloy slabs with a width of 70 mm and thickness of 10 mm were fabricated by heating-cooling combined mold（ HCCM） horizontal continuous casting. The effects of process parameters on solidification microstructure,surface quality,composition segregation and mechanical properties were studied. The results showed that the slabs with good surface quality,excellent mechanical properties and no obvious segregation could be prepared at the melt casting temperature of 1 250 ℃,the heating-mold temperature of 1 150- 1 200℃,the cooling water flow rate of 600 L / h and the casting speed of 20- 80 mm / min. The slabs had the yield strength of 124- 155 MPa,the elongation rate of 46. 6%- 56. 3% and the surface roughness of 0. 22- 0. 55μm,which enabled them to be directly processed without subsequent milling surface. The ratio of Sn content in the surface to that in the core was 0. 83- 1. 10,with an average value close to 1. 0,and not obviously influenced by process parameters. When the casting speed increased from 20 to 80 mm / min,the grain size changed little if the other process parameters were the same. When the heating-mold temperature increased from 1 150 to 1 200℃,the grain size was obviously refined and became more uniform if the casting speed was the same. Within the range of the casting speed at which the columnar grain structure could be obtained,the columnar grain size was mainly influenced by the heating-mold temperature.

关键词： QSn6.5 copper alloy Heating-cooling combined mold Horizontal continuous casting Microstructure Mechanical property Composition segregation

Lipomatous ependymoma with ZFTA:RELA fusion-positive:A case report

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World Journal of Clinical Cases 2025年第1期13卷 48-55页

作者： Xiao-Yu Zhao Juan-Han Yu Yi-hua Wang Yi-Xin liu Lu Xu Lin Fu Ning Yi China Medical University The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Department of Pathology The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Anshan Cancer Hospital Anshan 114000Liaoning ProvinceChina

BACKGROUND Ependymoma with lipomatous differentiation is a rare type of *** ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of central nervous system *** fusion-positive lipomatous ependymoma has not been reported to *** SUMMARY We reported a case of a 15-year-old Chinese male who had a sudden convulsion lasting approximately six *** resonance imaging showed a round cystic shadow of approximately 1.9 cm×1.5 cm×1.9 cm under the right parieto-occipital *** examination showed characteristic perivascular pseudorosettes and adipose differentiation in the ***-chemical staining showed that the tumor cells were negative for cytokeratin,NeuN,Syn and p53,but positive for GFAP,vimentin and S-100 ***-ficant punctate intracytoplasmic EMA immunoreactivity was *** level of Ki-67 was about 5%.Genetic analysis revealed ZFTA:RELA fusion.A cranio-tomy with total excision of the tumor was *** follow-up time was 36 months,no evidence of disease recurrence was found in magnetic resonance *** Based on these findings,the patient was diagnosed as a ependymoma with ZFTA fusion and lipomatous *** case report provides information on the microscopic morphological features of ependymoma with ZFTA fusion and lipomatous differentiation,which can help pathologists to make a definitive diagnosis of this tumor.

关键词： Ependymoma Lipomatous Molecular classification Supratentorial ZFTA:RELA fusion Case report

Spatial Distribution and Ecological Risk Assessment of Heavy Metals in Surface Sediment of Songhua River,Northeast China

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Chinese Geographical Science 2021年第2期31卷 223-233页

作者： liu Baolin dong Deming hua Xiuyi dong Weihua LI Ming Key Laboratory of Groundwater Resources and Environment of Ministry of Education College of New Energy and EnvironmentJilin UniversityChangchun 130012China College of Chemistry Changchun Normal UniversityChangchun 130032China College of Urban and Environmental Science Changchun Normal UniversityChangchun 130032China Key Laboratory of Songliao Aquatic Environment Ministry of EducationSchool of Civil and Environmental EngineeringJilin Jianzhu UniversityChangchun 130118China

The Songhua River,one of the seven major rivers in China,locates in Northeast China with 1897 km *** study aims to investigate the concentrations,distribution,source apportionment and ecological risk assessment of heavy metals including copper(Cu),zinc(Zn),cadmium(Cd),lead(Pb),nickel(Ni)and chromium(Cr)in main stream and tributaries of the Songhua River in Jilin Province,Northeast *** sediment samples(0–15 cm)were collected from 39 sampling sites in the Songhua River in July *** of Cu,Zn,Cd,Pb,Ni and Cr were *** mean concentrations of heavy metals were(24.0±9.2)mg/kg,(59.3±18.0)mg/kg,(4.0±2.1)mg/kg,(39.0±27.9)mg/kg,(18.5±8.6)mg/kg and(56.1±17.6)mg/kg for Cu,Zn,Cd,Pb,Cr and Ni,*** average contents of Cu,Cd,Pb,Cr and Ni were higher than their background *** concentrations of heavy metals were found in the lower reaches with industrial enterprises and cities along the Songhua ***,Pb and Ni might come from industrial sewage and mineral processing,while Cu and Cd were derived from electroplating wastewater and agricultural non-point source *** originated from lithogenic *** concentrations of Cu,Zn and Cr were below the effect range low(ERL)at all sites,while Cd,Pb and Ni concentrations were detected ranging from ERL to the effect range median(ERM)at more than 15%of *** of Ni exceeded ERM in more than 50%of *** mean toxic units of heavy metals in the Songhua River decreased following the order:Cd(6.7)>Pb(2.2)>Ni(1.6)>Cu(0.7)>Cr(0.5)=Zn(0.5).Potential ecological risk index was found to be higher in middle and lower reaches of the Songhua River,where Cd could impose an extremely high ecological risk.

关键词： heavy metals surface sediment ecological risk assessment Songhua River Northeast China

PVSS:A Progressive Vehicle Search System for Video Surveillance Networks

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Journal of Computer Science & Technology 2019年第3期34卷 634-644页

作者： Xin-Chen liu Wu liu hua-dong Ma Shuang-Qun Li Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia Beijing University of Posts and TelecommunicationsBeijing 100876China

This paper is focused on the task of searching for a specific vehicle that appears in the surveillance *** methods usually assume the vehicle images are well cropped from the surveillance videos,and then use visual attributes,like colors and types,or license plate numbers to match the target vehicle in the image ***,a complete vehicle search system should consider the problems of vehicle detection,representation,indexing,storage,matching,and so ***,it is very difficult for attribute-based search to accurately find the same vehicle due to intra-instance changes in different cameras and the extremely uncertain ***,the license plates may be mis-recognized in surveillance scenes due to the low resolution and *** this paper,a progressive vehicle search system,named as PVSS,is designed to solve the above *** is constituted of three modules:the crawler,the indexer,and the *** vehicle crawler aims to detect and track vehicles in surveillance videos and transfer the captured vehicle images,metadata and contextual information to the server or *** multi-grained attributes,such as the visual features and license plate fingerprints,are extracted and indexed by the vehicle *** last,a query triplet with an input vehicle image,the time range,and the spatial scope is taken as the input by the vehicle *** target vehicle will be searched in the database by a progressive *** experiments on the public dataset from a real surveillance net work validate the effec tiveness of PVSS.

关键词： multi-modal data analysis progressive search system vehicle search video surveillance network

Research on Rolling Load Distribution Method based on Data Mining

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Journal of Iron and Steel Research International 2005年第6期12卷 30-32,53页

作者： ZHANG Yan-hua liu Xiang-hua WANG Guo-dong Northeastern University Shenyang 110004 China Shenyang Institute of Chemical Technology Shenyang 110142 China

A new method of establishing rolling load distribution model was developed by online intelligent information-processing technology for plate rolling. The model combines knowledge model and mathematical model with using knowledge discovery in database （KDD） and data mining （DM） as the start. The online maintenance and optimization of the load model are realized. The effectiveness of this new method was testified by offline simulation and online application.

关键词： rolling load distribution information processing knowledge discovery data mining

Genome-wide characterization and expression analysis of WRKY family genes during development and resistance to Colletotrichum fructicola in cultivated strawberry(Fragaria×ananassa Duch.)

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Journal of Integrative Agriculture 2022年第6期21卷 1658-1672页

作者： ZOU Xiao-hua dong Chao liu Hai-ting GAO Qing-hua Shanghai Key Laboratory of Protected Horticultural Technology Forestry and Fruit Tree Research InstituteShanghai Academy of Agricultural Sciences(SAAS)Shanghai 201403P.R.China

Based on the recently published whole-genome sequence of cultivated strawberry ’Camarosa’, in this study, 222FaWRKY genes were identified in the ’Camarosa’ genome. Phylogenetic analysis showed that the 222 FaWRKY candidate genes were classified into three groups, of which 41 were in group Ⅰ, 142 were in group Ⅱ, and 39 were in group Ⅲ. The 222 FaWRKY genes were evenly distributed among the seven chromosomes. The exon–intron structures and motifs of the WRKY genes had evolutionary diversity in different cultivated strawberry genomes. Regarding differential expression, the expression of FaWRKY133 was relatively high in leaves, while FaWRKY63 was specifically expressed in roots. FaWRKY207, 59, 46, 182, 156, 58, 39, 62 and 115 were up-regulated during achene development from the green to red fruit transition. FaWRK181, 166 and 211 were highly expressed in receptacles at the ripe fruit stage. One interesting finding was that Fa WRKY179 and 205 were significantly repressed after Colletotrichum fructicola inoculation in both ’Benihoppe’ and ’Sweet Charlie’ compared with Mock. The data reported here provide a foundation for further comparative genomics and analyses of the distinct expression patterns of FaWRKY genes in various tissues and in response to C. fructicola inoculation.

关键词： Fragaria×ananassa FaWRKY Colletotrichum fructicola structure evolution

Results of the maximum genus of graphs

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Science China Mathematics 2007年第11期50卷 1563-1570页

作者： Guang-hua dong Yan-pei liu Department of Mathematics School of ScienceBeijing Jiaotong UniversityBeijing 100044China Department of MathematicsSchool of ScienceBeijing Jiaotong UniversityBeijing 100044China

In this paper,we provide a new class of up-embeddable graphs,and obtain a tight lower bound on the maximum genus of a class of 2-connected pseudographs of diameter 2 and of a class of diameter 4 *** extends a result o... 详细信息

关键词： maximum genus up-embeddable diameter