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A Method for Predicting Service Deprecation in Service Systems

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Tsinghua Science and Technology 2017年第1期22卷 52-61页

作者： Bofei Xia yushun Fan Cheng Wu Bing Bai Junqi Zhang Department of Automation Tsinghua UniversityBeijing 100084 China

An increasing number of web services are being invoked by users to create user applications（e.g.,mashups）. However, over time, a few good services in service systems have become deprecated, i.e., the service is initially available and is invoked by service users, but later becomes unavailable. Therefore, the prediction of service deprecation has become a key issue in creating reliable long-term user applications. Most existing research has overlooked service deprecation in service systems and has failed to consider long-term service reliability when making service recommendations. In this paper, we propose a method for predicting service deprecation, which comprises two components： Service Comprehensive Feature Modeling（SCFM） for extracting service features relevant to service deprecation and Deprecated Service Prediction（DSP） for building a service deprecation prediction model. Our experimental results on a real-world dataset demonstrate that our method yields an improved Area-Under-the-Curve（AUC） value over existing methods and thus has better accuracy in service deprecation prediction.

关键词： web service service deprecation predict Latent Dirichlet Allocation(LDA) extreme learning machine

GeometricNumerical Integration for Peakon b-Family Equations

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Communications in Computational Physics 2016年第1期19卷 24-52页

作者： Wenjun Cai Yajuan Sun yushun Wang Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China LSEC Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Jiangsu Provincial Key Laboratory for NSLSCS School of Mathematical SciencesNanjing Normal University Nanjing 210023China

In this paper,we study the Camassa-Holm equation and the Degasperis-Procesi *** two equations are in the family of integrable peakon equations,and both have very rich geometric *** on these geometric structures,we construct the geometric numerical integrators for simulating their soliton *** Camassa-Holm equation and the Degasperis-Procesi equation have many common properties,however they also have the significant difference,for example there exist the shock wave solutions for the Degasperis-Procesi *** using the symplectic Fourier pseudo-spectral integrator,we simulate the peakon solutions of the two *** illustrate the smooth solitons and shock wave solutions of the DP equation,we use the splitting technique and combine the composition *** the numerical experiments,comparisons of these two kinds of methods are presented in terms of accuracy,computational cost and invariants preservation.

关键词： Symplectic integrator splitting method WENO scheme multisymplectic integrator peakon shockpeakon

A LINEARLY-IMPLICIT STRUCTURE-PRESERVING EXPONENTIAL TIME DIFFERENCING SCHEME FOR HAMILTONIAN PDEs

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Journal of Computational Mathematics 2024年第4期42卷 1063-1079页

作者： Yayun Fu Dongdong Hu Wenjun Cai yushun Wang Henan Joint International Research Laboratory of High Performance Computation for Complex Systems School of ScienceXuchang UniversityXuchang 461000China School of Mathematics and Statistics Jiangxi Normal UniversityJiangxiNanchang 330022China Jiangsu Key Laboratory for NSLSCS Jiangsu Collaborative Innovation Center of Biomedial Functional MaterialsSchool of Mathematical SciencesNanjing Normal UniversityNanjing 210023China

In the paper,we propose a novel linearly implicit structure-preserving algorithm,which is derived by combing the invariant energy quadratization approach with the exponential time differencing method,to construct efficient and accurate time discretization scheme for a large class of Hamiltonian partial differential equations(PDEs).The proposed scheme is a linear system,and can be solved more efficient than the original energy-preserving ex-ponential integrator scheme which usually needs nonlinear *** experiments are performed to verify the conservation,efficiency and good performance at relatively large time step in long time computations.

关键词： Structure-preserving algorithm Hamiltonian PDE Energy quadratization method Exponential time differencing

A comparison of zooplankton assemblages in Nansi Lake and Hongze Lake,potential influences of the East Route of the South-to-North Water Transfer Project,China

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Journal of Oceanology and Limnology 2021年第2期39卷 623-636页

作者： Kandathil Radhakrishnan DIVYA Shasha ZHAO yushun CHEN Fei CHENG Lei ZHANG Jiao QIN Thundiparambil Sathrajith ARUNJITH V.Bjorn SCHMIDT Songguang xie Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Key Laboratory of Sustainable Fisheries and Environmental Protection for Lakes of Northern Jiangsu Huai’an Research CenterInstitute of HydrobiologyChinese Academy of SciencesHuai’an 223002China

Nansi Lake and Hongze Lake are both water storage lakes along the East Route of the South-to-North Water Transfer project(ESNT).Frequent changes in hydrologic properties are responsible factors for controlling the zooplankton community assemblages in both lakes,so we studied the possible influence of water transfer and environmental factors on zooplankton community structure and *** assemblages were investigated seasonally for one year in both lakes;a total of 133 and 122 zooplankton taxa were identified in Nansi Lake and Hongze Lake,*** most dominant rotifer species were littoral,e.g.,Keratella tecta,Keratella valga and Lecane lunaris in Nansi Lake and Brachionus angularis,Brachionus forficula and Polyarthra vulgaris in Hongze ***,Nansi Lake had a higher Shannon-Wiener diversity index value(5.13),while Hongze Lake had a higher species richness index(4.21).The average number of zooplankton across seasons in Nansi Lake(protozoa:774±63 ind./L,rotifers:4817±212 ind./L,cladocerans:896±14 ind./L,copepod:435±42 ind./L)was comparatively lower than Hongze Lake(protozoa:1238±63 ind./L,rotifers:6576±112 ind./L,cladocerans:1013±20 ind./L,copepod:534±25 ind./L).Canonical correspondence analysis identified differing environmental gradients that were most responsible for influencing zooplankton communities in the two lakes(Hongze Lake:NH4-N,total nitrogen,transparency and pH;Nansi:pH,temperature and total phosphorus).Frequent changes related to water transfer in lakes favoured the diversity of rotifers and protozoa *** habitat preference,changes in community structure and opportunistic peaks and extinction of certain taxa were also observed in the study lakes.

关键词： zooplankton assemblage water transfer Hongze Lake Nansi Lake

血小板衍生生长因子DD对人肌腱源性干细胞增殖和多向分化能力的影响

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中国组织工程研究 2025年第31期29卷 6649-6655页

作者：文华伟张青松汤明李亚楠谈鸿飞方禹舜武汉市第四医院湖北省武汉市430030 湖北省运动医学中心湖北省武汉市430030

背景:慢性肩袖损伤常伴有肌腱退变和肌腱干细胞功能受损,血小板衍生生长因子DD作为一种重要的细胞因子,对干细胞增殖和分化具有调节作用。目的:探讨血小板衍生生长因子DD对人慢性肩袖损伤组织来源肌腱干细胞增殖和多向分化能力的影响。... 详细信息

背景:慢性肩袖损伤常伴有肌腱退变和肌腱干细胞功能受损,血小板衍生生长因子DD作为一种重要的细胞因子,对干细胞增殖和分化具有调节作用。目的:探讨血小板衍生生长因子DD对人慢性肩袖损伤组织来源肌腱干细胞增殖和多向分化能力的影响。方法:获取人体慢性肩袖损伤组织标本并体外分离培养肌腱干细胞,免疫荧光染色观察细胞的骨架形态,流式检测肌腱干细胞表型表达。将肌腱干细胞分成2组:对照组不进行任何干预,血小板衍生生长因子DD组以5μg/mL血小板衍生生长因子DD干预,通过细胞增殖实验和三系分化实验评估血小板衍生生长因子DD对肌腱干细胞增殖和多向分化能力的影响。结果与结论:①血小板衍生生长因子DD组EdU阳性细胞数量较对照组显著增加(P<0.05),且肌腱干细胞更早进入快速增殖期,细胞呈对数增长;②血小板衍生生长因子DD组油红O染色、阿利新蓝染色、茜素红染色阳性面积较对照组明显增大(P<0.05);③上述结果表明,血小板衍生生长因子DD显著促进肌腱干细胞的增殖和成脂、成骨、成软骨分化。

关键词：肌腱干细胞肌腱源性干细胞血小板衍生生长因子DD 肩袖损伤肩袖修复工程化干细胞

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Research on an Agile Manufacturing Information System

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Journal of Systems Engineering and Electronics 2000年第3期11卷 22-27页

作者： Xu, Qingsong Fan, yushun Tao, Dan Dept. of Automation Tsinghua University Beijing 100084 P. R. China

With the more intense competition in the worldwide market, the agile virtual enterprise (AVE) will become a new organization form of manufacturing enterprise. To support the new relationship, an agile manufacturing information system (AMIS) is described in this paper which serves to assist the virtual enterprise to manage and control information flow among collaborating partners. Based on the requirement analysis of virtual information system, the architecture, functions, features and execution scheme of AMIS are discussed in detail.

关键词： Agile manufacturing information system (AMIS) Dynamic collaboration Distributed workflow management Agent.

Temperature‐dependent adaptive conductivity coating for surface charge release and electric field control under electro‐thermal coupling field

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High Voltage 2023年第5期8卷 1082-1092页

作者： Jianyi Xue Zhu Zhang Binbin Li yushun Zhao Lijian Ding School of Electrical Engineering and Automation Hefei University of TechnologyHefeiChina Electric Power Research Institute of State Grid Anhui Electric Power Co. Ltd.HefeiChina

Surface charge accumulation is the potential criminal for surface insulation failure on spacers under direct current(DC)*** existence of thermal gradient posing the difficulty of surface charge *** study proposes a temperature‐dependent adaptive conductivity coating technique for surppressing surface charge accumulation under electro‐thermal coupling field.A two‐dimensional axis‐symmetrical simulation model regrading surface charge computation is *** effects of thermal gradients and coating conductivity on surface charge and electric field distribution are *** results show that the thermal gradient increases the bulk conductive current,therefore aggravating surface charge *** effects of the coating condcutivity on surface charge and electric field contains three *** lower coating conductivity leads to aggravated homo‐polarity charge *** increasing the coating conductivity,the surface charge and electric field are significantly suppressed at the obtained optimal conductivity,where the bulk and surface conductive current reach a balance *** increasing the coating conductivity results in aggravated hetero‐polarity ***,the increase of thermal gradient to an appropriate extent contributes to the further suppression of surface charge on coated *** is hoped that this study could provide some references for designing highly reliable DC GIL under electro‐thermal coupling field.

关键词： coating charge conductivity

Theoretical Analysis on Deflection and Bearing Capacity of Prestressed Bamboo-Steel Composite Beams

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Journal of Renewable Materials 2024年第1期12卷 149-166页

作者： Qifeng Shan Ming Mao yushun Li School of Civil Engineering Zhejiang Industry Polytechnic CollegeShaoxing312000China School of Civil&Environmental Engineering and Geography Science Ningbo UniversityNingbo315211China College of Civil Engineering and Architecture Qingdao Agricultural UniversityQingdao266109China

A theoretical analysis of upward deflection and midspan deflection of prestressed bamboo-steel composite beams is presented in this *** deflection analysis considers the influences of interface slippage and shear ***,the calculation model for flexural capacity is proposed considering the two stages of *** theoretical results are verified with 8 specimens considering different prestressed load levels,load schemes,and prestress *** results indicate that the proposed theoretical analysis provides a feasible prediction of the deflection and bearing capacity of bamboo-steel composite *** deflection analysis,the method considering the slippage and shear deformation provides better *** theoretical method for bearing capacity matches well with the test results,and the relative errors in the serviceability limit state and ultimate limit state are 4.95%and 5.85%,respectively,which meet the accuracy requirements of the engineered application.

关键词： Bamboo scrimber composite beam prestress deflection bearing capacity

Implementation of WPDL Conforming Workflow Model

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Tsinghua Science and Technology 2003年第2期8卷 139-144页

作者： ZHANG Zhijun(张志君) FAN yushun(范玉顺) Department of Automation Tsinghua University Beijing 100084 China Department of Automation Tsinghua University Beijing 100084 China

Workflow process definition language (WPDL) facilitates the transfer of workflow process definitions between separate workflow products. However, much work is still needed to transfer the specific workflow model to a WPDL conforming model. CIMFlow is a workflow management system developed by the National CIMS Engineering Research Center. This paper discusses the methods by which the CIMFlow model conforms to the WPDL meta-model and the differences between the WPDL meta-model and the CIMFlow model. Some improvements are proposed for the WPDL specification. Finally, the mapping and translating methods between the entities and attributes are given for the two models. The proposed methods and improvements are valuable as a reference for other mapping applications and the WPDL specification.

关键词： Computer integrated manufacturing Computer software