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SSDBA:the stretch shrink distance based algorithm for link prediction in social networks

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Frontiers of Computer Science 2021年第1期15卷 69-80页

作者： Ruidong YAN Yi li deying li Weili WU Yongcai WANG School of Information Renmin University of ChinaBeijing 100872China Department of Computer Science University of Texas at DallasRichardsonTexas 75080USA

In the field of social network analysis,link Predic-tion is one of the hottest topics which has been attracted attentions in academia and industry.So far,literatures for solving link prediction can be roughly divided into two categories:similarity-based and learning-based methods.The learning-based methods have higher accuracy,but their time complexities are too high for complex networks.However,the similarity-based methods have the advantage of low time consumption,so improving their accuracy becomes a key issue.In this paper,we employ community structures of social networks to improve the prediction accuracy and propose the stretch shrink distance based algorithm(SSDBA),In SSDBA,we first detect communities of a social network and identify active nodes based on community average threshold(CAT)and node average threshold(NAT)in each community.Second,we propose the stretch shrink distance(SSD)model to iteratively calculate the changes of distances between active nodes and their local neighbors.Finally,we make predictions when these links'distances tend to converge.Furthermore,extensive parameters learning have been carried out in experiments.We compare our SSDBA with other popular approaches.Experimental results validate the effectiveness and efficiency of proposed algorithm.

关键词： link prediction social network stretch shrink distance model dynamic distance community detection

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库水位降速对缓倾角堆积层滑坡稳定性的影响

安全与环境工程 2024年第3期31卷 198-205页

作者：冉爱民杨威彭嘉畅刘远松甘银波余斯迪杨硕李德营贵州蒙江流域开发有限公司贵州都匀558000 中国地质大学(武汉)工程学院湖北武汉430074

缓倾角堆积层滑坡为库区常见的地质灾害类型,其常表现为体积规模大、物质成分复杂,滑坡变形呈现周期性和长期性。库水位下降常是诱发该类滑坡变形破坏的重要因素,因此研究库水位下降速率对缓倾角堆积层滑坡稳定性的影响具有重要意义。... 详细信息

缓倾角堆积层滑坡为库区常见的地质灾害类型,其常表现为体积规模大、物质成分复杂,滑坡变形呈现周期性和长期性。库水位下降常是诱发该类滑坡变形破坏的重要因素,因此研究库水位下降速率对缓倾角堆积层滑坡稳定性的影响具有重要意义。以缓倾角堆积层滑坡——贵州何家坪子滑坡为例,研究不同库水位下降速度(0.5、0.7、0.9、1.1、1.3 m/d)条件下滑坡不同滑体物质结构对库水位下降速度的响应差异。结果表明:不同库水位下降速度条件下,滑坡不同部位的稳定性均表现出先下降后上升的变化趋势,并且随着库水位下降速度的增大滑坡稳定性系数的下降幅度也增大;滑体渗透性弱的区域变形比滑体渗透性强的区域大;模拟结果与现场监测数据吻合,滑坡稳定性对于库水位下降速度的响应呈现明显的空间差异性。在缓倾角堆积层滑坡的风险防控中,应充分考虑库水位调节速度、滑体物质结构与滑坡变形的关系。

关键词：缓倾角堆积层滑坡库水位下降速度滑体结构差异滑坡稳定性

Study on the Influence of Non-electrical Parameters on Processing Quality of WEDM-HS and Improvement Measures

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Study on the Influence of Non-electrical Parameters on Proce...

基于SBAS-InSAR技术的高山峡谷区滑坡隐患早期识别

Computer and Computing Technologies in Agriculture IV——4th IFIP TC 12 Conference(CCTA2010) Part IV

作者： Guangyao Xiong Meizhu Zheng deying li Longzhi Zhao Yanlin Wang Minghui li School of Mechanical and Electrical Engineering East China Jiaotong University Department of Plastic Forming Shanghai Jiaotong University

The high-speed wire electrical discharge machining（WEDM-HS）machine has been more and more favoured by customers for the low manufacturing cost,the degree of automation and the advantages over the WEDM-LS in price performance ratio.However,the processing quality（the precision of form and position and the surface quality） of WEDM-HS is poorer than that of WEDM-LS,and the processing quality is one of the main technical indicators of WEDM.There are many factors on the processing quality of WEDM-HS,the effects of non-electrical parameters,including the machine precision,the wire-moving system and wire-moving way of the wire electrode and the working solution,on the processing quality of WEDM-HS are discussed,and the corresponding measures of improving the processing quality are put forward,which provide the sufficient basis for further improving the processing quality of WEDM-HS.

关键词： WEDM-HS Non-electrical parameters Processing quality Improvement measure.

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安全与环境工程 2024年第3期31卷 206-216页

作者：陈宏江峻毅纪成亮张伟杨庆义孙旭席文勇张勇刘玉洁李德营国家电力投资集团有限公司安环部北京100029 山东电力工程咨询院有限公司勘测事业部山东济南250100 中国地质大学(武汉)工程学院湖北武汉430074

近年来,高山峡谷区滑坡灾害频发,给人民生命和财产安全带来了严重威胁。滑坡隐患早期识别是高山峡谷区滑坡研究的重点和难点问题之一。以牛栏江中下游河段的象鼻岭水库区域为研究区,基于SBAS-InSAR技术,在分析地形可视性的基础上,通过Se... 详细信息

近年来,高山峡谷区滑坡灾害频发,给人民生命和财产安全带来了严重威胁。滑坡隐患早期识别是高山峡谷区滑坡研究的重点和难点问题之一。以牛栏江中下游河段的象鼻岭水库区域为研究区,基于SBAS-InSAR技术,在分析地形可视性的基础上,通过Sentinel-1A升、降轨数据结合互补的方式,对该区域的滑坡隐患进行早期识别研究。结果表明:升、降轨数据结合有效减小了阴影叠掩区的干扰,能够较全面地识别出高山峡谷区的滑坡隐患点;研究区内雷达视线方向的年平均形变速率为-186~166 mm/a,基于形变结果识别出47个滑坡隐患点;高程在1400~<1600 m、坡度在30°~<40°、坡向在东北和正南方向为滑坡发育的有利地形,大部分滑坡分布在石炭系下统岩关组地层中。研究成果证明了基于SBAS-InSAR技术采用升、降轨数据结合互补方式在高山峡谷区滑坡隐患早期识别中的优势及有效性,具有推广应用的潜力。

关键词：滑坡隐患早期识别高山峡谷区 SARS-InSAR技术地形可视性

Mechanical Analysis for Progressive Failure of Debris Landslide

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Journal of Mountain Science 2011年第2期8卷 328-335页

作者： MIAO Haibo YIN Kunlong li deying Faculty of Engineering China University of Geosciences Wuhan 430074 China

It is of significance to research failure mechanism of debris landslides that are widespread in the Three Gorges Reservoir Area. Based on the statistical analysis of the developmental law and failure mode of debris landslides in the Three Gorges Reservoir, the mode of progressive failure is found. The mechanical model for progressive failure of debris landslides with two slip bands is also established by applying slice method. According to the results of the downslide force between adjacent slices, if the downslide force of lower slice is larger than zero, the slice fails along the major sliding surface, otherwise it is stable. In result, the failure range is obtained. The stress function can be determined through dimensional analysis of failure slice. According to static boundary conditions of the slice, stress state of any point in the slice can be obtained. Then stress state of any point in the secondary slip band can also be established. The failure of the secondary slip band is judged on the basis of Mohr-Coulomb failure criterion. Therefore, a mechanical method is proposed to analyze the progressive failure of debris landslide with two slip bands.

关键词：泥石流滑坡渐进破坏机械分析故障模式滑移带切片法三峡库区统计分析

Fine Machining of Large-Diameter 6H-SiC Wafers

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Journal of Materials Science & Technology 2006年第5期22卷 681-684页

作者： Xiufang CHEN Juan li deying MA Xiaobo HU Xiangang XU Minhua JIANG State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

Three main machining processes of large-diameter 6H-SiC wafers were introduced in this paper. These processes include cutting, lapping and polishing. Lapping causes great residual stresses and deep damage layer which can be reduced gradually with subsequent polishing processes. Surfaces prepared by mechanical polishing （MP） appeared a large number of scratches with depth of 5-8 nm. These scratches can be effectively removed by chemo-mechanical polishing （CMP）. After CMP. extremely smooth and low damage layer surface with roughness Ra=0.3 nm was obtained. Atomic force microscopy （AFM） and optical microscopy were used to observe the surface morphology of samples and a high resolution X-ray diffractometer （HRXRD） was used for the crystal lattice perfection of the subsurface region. Changes of surface residual stresses during machining processes were investigated by HRXRD.

关键词： 6H-SiC Chemo-mechanical polishing （CMP） Roughness

Mapk7 deletion in chondrocytes causes vertebral defects by reducing MEF2C/PTEN/AKT signaling

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Genes & Diseases 2024年第2期11卷 964-977页

作者： Chengzhi Wu Hengyu liu Dongmei Zhong Xiaoming Yang Zhiheng liao Yuyu Chen Shun Zhang deying Su Baolin Zhang Chuan li liru Tian Caixia Xu Peiqiang Su Guangdong Provincial Key Laboratory of Orthopedics and Traumatology Department of Spine SurgeryThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Research Center for Translational Medicine The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Precision Medicine Institute The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Department of Orthopedics Renmin Hospital of Wuhan UniversityWuhanHubei 430060China Guangdong Provincial Key Laboratory of Proteomics and State Key Laboratory of Organ Failure Research School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China

Mutation of the MAPK7 gene was related to human scoliosis.Mapk7 regulated the development of limb bones and skulls in mice.However,the role of MAPK7 in vertebral development is still unclear.In this study,we constructed Col2a1-cre;Mapk7 f/f transgenic mouse model to delete Mapk7 in cartilage,which displayed kyphosis and osteopenia.Mechanistically,Mapk7 loss decreased MEF2C expression and thus activated PTEN to oppose PI3K/AKT signaling in vertebral growth plate chondrocytes,which impaired chondrocyte hypertrophy and attenuated vertebral ossification.In vivo,systemic pharmacological activation of AKT rescued impaired chondrocyte hypertrophy and alleviated mouse vertebral defects caused by Mapk7 deficiency.Our study firstly clarified the mechanism by which MAPK7 was involved in vertebral development,which might contribute to understanding the pathology of spinal deformity and provide a basis for the treatment of developmental disorders of the spine.

关键词： Chondrocyte hypertrophy Growth plate Kyphosis MAPK7 MEF2C Osteopenia PI3K/AKT PTEN

Age Assignment of the Lycoptera- bearing Bed

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Acta Geologica Sinica(English Edition) 1994年第3期68卷 329-347页

作者： li Peixian, Su deying, li Yougui and Yu JingxianInstitute of Geology, Chinese Academy of Geological Sciences, Beijing Chinese Academy of Geological Sciences Beijing

In the Yanliao area, the occurrence of the Nestoria-Keratestheria fauna and the Eoparacypris- Luanpingella-Darwinula assemblage in the Dabeigou Formation s.s., a Rb-Sr isochron age of 145.2 Ma for the Baiqi Formation and a complete stratigraphic sequence-all this proves that the Lycoptera-bearing bed overlies the Upper Jurassic. The Jehol fauna comprises the primitive Trigonioidids fauna, Eosestheria fauna, Lycoptera fauna et al., and their own laws of evolution expound that they belong to Cretaceous faunas. The associations of Eosestheria with Yanjiestheria, Lycoptera with Eosestheria, and Kuntulunia with Yanjiestheria as well as the occurrence of early angiosperms and sporo - pollen in the Fuxin Formation and its equivalents also demonstrate that the Lycoptera-bearing, bed should be assigned to the Cretaceous. The confirmation of the existence of Aucellina in the Jixi Group and the correlation of Trigonioidids and Cypridids with those in the equivalent strata of Japan and Western Europe have also been verified by corresponding marine strata. According to the magnetostratigraphic data from Zhejiang and Songliao, it has been preliminarily ascertained that M0 between the mixed polarity zone in the lower part and the normal polarity zone in the middle part of the Cretaceous is located in the upper member of the Huangjian Formation of the Jiande Group and the top member of the Denglouku Formation of the same group, and the isotopic age data of the Jehol and Jiande Groups show that the approximate geologic age of the Lycoptera bed is 135-122 Ma. These prove that the Lycoptera bed should be assigned to the Cretaceous.

关键词： Cretaceous Jurassic-Cretaceous boundary Lycoptera- bearing bed Jehol fauna

建筑形态与精神符号:三线建设初期“干打垒”研究(1964—1966)

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史林 2023年第2期 198-207,220页

作者：李德英朱领四川大学历史文化学院 610207

中共中央在决策三线建设时确立了“先生产、后生活”的基本原则,要求在非生产性的建设方面学习大庆精神,因陋就简,兴建“干打垒”,降低成本,将更多资金和材料投入生产领域。攀枝花工业基地是较早修筑“干打垒”的三线地区,而四川广安华... 详细信息

中共中央在决策三线建设时确立了“先生产、后生活”的基本原则,要求在非生产性的建设方面学习大庆精神,因陋就简,兴建“干打垒”,降低成本,将更多资金和材料投入生产领域。攀枝花工业基地是较早修筑“干打垒”的三线地区,而四川广安华光仪器厂因在“干打垒”试验中取得成功并形成经验,被上级机关树立为典型,加以推广。初到三线地区时,建设者们对推广“干打垒”并不积极。在经历一系列政治动员和思想工作后,他们逐渐接受并参与修建“干打垒”。“干打垒”因其自身优点有效缓解了基建压力,各地因地制宜的实践则促进了“干打垒”建筑形式的多样化。推广“干打垒”的过程也是践行“干打垒”精神的过程,“干打垒”不仅是一种建筑形态,它同延安窑洞一样,演变成特定时代具有多重意义的精神符号。

关键词：三线建设 “干打垒” 建筑形态精神符号