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城市燃气管道风险评价研究综述

当代化工研究 2023年第17期 23-25页

作者：杨斯涵许开立鞍钢集团矿业设计研究院有限公司辽宁114004 东北大学资源与土木工程学院辽宁110819

城市燃气的使用率和燃气管道铺设率日益上涨,其潜在的风险因素也日益增多,本文将燃气管道风险评价方法分类归纳,从传统风险评价方法、动态风险评价方法和新兴的风险评价方法三方面分类介绍,阐述这三类风险评价方法在国内外燃气管道风险... 详细信息

城市燃气的使用率和燃气管道铺设率日益上涨,其潜在的风险因素也日益增多,本文将燃气管道风险评价方法分类归纳,从传统风险评价方法、动态风险评价方法和新兴的风险评价方法三方面分类介绍,阐述这三类风险评价方法在国内外燃气管道风险研究中的应用现状,结合现有燃气管道风险评价存在的一些问题,对未来的燃气管道风险研究提出建议。

关键词：安全工程燃气管道事故统计风险评价研究现状

New Second-Level-Discrete Zeroing Neural Network for Solving Dynamic Linear System

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1521-1523页

作者： Min yang School of Robotics Hunan UniversityChangsha 410082China

Dear Editor,This letter deals with a new second-level-discretization method with higher precision than the traditional first-level-discretization ***,the traditional discretization method utilizes the first-order time derivative information,and it is termed first-level-discretization *** contrast,the new discretization method not only utilizes the first-order time derivative information,but also makes use of the second-order derivative *** combining the new second-level-discretization method with zeroing neural network(ZNN),the second-level-discrete ZNN(SLDZNN)model is proposed to solve dynamic(i.e.,time-variant or time-dependent)linear *** experiments and application to angle-of-arrival(AoA)localization show the effectiveness and superiority of the SLDZNN model.

关键词： method derivative utilize

New Insight into the Flexoelectricity in the View of Mechanics of Materials:Prismatic Beams Subjected to Bending

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Acta Mechanica Solida Sinica 2024年第4期37卷 555-569页

作者： Xu yang Lingling Chen Shengyou yang Department of Engineering Mechanics School of Civil EngineeringShandong UniversityJinan250061China

Flexoelectricity is a fascinating electromechanical phenomenon that occurs in non-homogeneously deformed dielectric *** piezoelectricity,the flexoelectric effect is highly dependent on both the material scale and the deformation *** several theoretical models have been proposed to explain the mechanism of flexoelectricity,these models can be rather complicated for those who are interested in studying the *** paper aims to simplify the understanding of flexoelectricity by focusing on the bending behavior of a prismatic dielectric beam from a mechanics of material *** avoid using complicated mathematical formulations based on continuum mechanics,including advanced tensor algebra and calculus of *** formulation clearly explains how inhomogeneous deformations and material size affect the electromechanical coupling,changing the effective bending stiffness,deflection,and rotation angles of a bending *** hope this paper can help undergraduate students and researchers,who are unfamiliar with the electromechanical coupling in flexoelectricity,to develop an understanding of this phenomenon and encourage further research in this area.

关键词： bending formulation dielectric

Assessing Coarctation of the Aorta With Fetal Heart Quantification Technology

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Maternal-Fetal Medicine 2024年第3期6卷 147-155页

作者： Jiaojiao yang Fang Tan Yuqin Shen Yuan Zhao Yan Xia sihan Fan Xueqin Ji Department of Obstetrics and Gynecology Center General Hospital of Ningxia Medical UniversityYinchuanNingxia 750003China Ultrasound Medicine Department Xian Yang Central HospitalXianyangShaanxi 712099China Ultrasound Medicine Department Peking University First Hospital Ningxia Women’s and Children's Hospital(Ningxia Hui Autonomous Region Maternal and Child Health Hospital)YinchuanNingxia 750002China Ningxia Medical University YinchuanNingxia 750004China

Objective:To use fetal heart quantification(fetal HQ)technology to compare the coarctation of the aorta(CoA)and normal fetal heart structure and systolic function and to assess whether there are abnormalities in the fetal heart structure and systolic function associated with ***:This prospective cohort study was conducted from May 2020 to December 2022 and involved 18–40-week-old singleton pregnancies and 30 fetuses diagnosed with CoA using fetal echocardiography at the General Hospital of Ningxia Medical University and Peking University First Hospital Ningxia Women’s andChildren’s Hospital,*** control group contained 60 normal *** following parameters were recorded and analyzed statistically:four-chamber view(4CV)end-diastolic long diameter,4CV epicardial–contralateral epicardial transverse maximum diameter,4CV global sphericity index(GSI),left ventricular(LV)and right ventricular(RV)24-segment end-diastolic diameter(EDD),24-segment sphericity index(SI),LV-fractional area change(LV-FAC),LV-longitudinal strain(LV-LS),RV-fractional area change(RV-FAC),RV-longitudinal strain(RV-LS),and LV and RV 24-segment transverse fractional shortening(FS).Measurement data were compared between the two groups using an independent sample t test,with P0.9,indicating high consistency,and a coefficient of variable of<1%,indicating low *** analysis revealed no obvious correlation between gestational age and GSI,LV-FAC,LV-LS,RV-FAC,and RV-LS.A comparison of the fourchamber morphological structural parameters of the hearts in the two groups revealed that when compared with the control group,the 4CV end-diastolic long diameter was shortened in

关键词： Fetal heart Quantitative analysis technology Fetal HQ software Coarctation of the aorta Spherical index Systolic function

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多边形样地精度研究

林业资源管理 2013年第6期 81-85+91页

作者：郭志文岳德鹏曹睿杨丝涵北京市规划委员会北京林业大学

在北京市山区选取20块油松标准样地,按照多边形样地布设的原理,在其中布设100块多边形样地进行测量,并对测量所得的样地林分平均树高、平均胸径、平均密度以及蓄积量与标准样地每木检尺数据进行对比分析,得到多边形样地的调查精度。结... 详细信息

在北京市山区选取20块油松标准样地,按照多边形样地布设的原理,在其中布设100块多边形样地进行测量,并对测量所得的样地林分平均树高、平均胸径、平均密度以及蓄积量与标准样地每木检尺数据进行对比分析,得到多边形样地的调查精度。结果表明,多边形样地法调查数据在人工林中精度高于天然林中,人工林中蓄积量精度可以达到92.8%,而在天然林中,蓄积量精度可以达到89.2%。

关键词：多边形样地法森林资源调查精度

Effect of Epoxy Resin on the Properties of Recycled Asphalt

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1149-1155页

作者： yang Ruochong CHEN Huimin yang Jun School of Transportation Southeast UniversityNanjing 211189China

To promote the recycling of reclaimed asphalt pavement(RAP),epoxy resin was used to prepare the epoxy-recycled asphalt *** effect of epoxy resin on the properties of aged asphalt binder was investigated based on the tensile test,flexural creep test,and laser scanning confocal *** curing characteristics and the mechanical performance of recycled asphalt with different epoxy contents were *** results show that the low-temperature performance,ductility,and strength of the aged asphalt binder were significantly improved when the epoxy content reached 40%.The curing time of epoxy-recycled asphalt should be at least 4 d to ensure the formation of good internal spatial network structure.

关键词： RAP epoxy resin aged asphalt mechanical performance

Alignment efficient image-sentence retrieval considering transferable cross-modal representation learning

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Frontiers of Computer Science 2024年第1期18卷 77-91页

作者： yang yang Jinyi GUO Guangyu LI Lanyu LI Wenjie LI Jian yang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computing Hong Kong Polytechnic UniversityHong Kong 100872China State Key Lab.for Novel Software Technology Nanjing UniversityNanjing 210094China 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210094China guangyu.li2017@***

Traditional image-sentence cross-modal retrieval methods usually aim to learn consistent representations of heterogeneous modalities,thereby to search similar instances in one modality according to the query from another modality in *** basic assumption behind these methods is that parallel multi-modal data(i.e.,different modalities of the same example are aligned)can be obtained in *** other words,the image-sentence cross-modal retrieval task is a supervised task with the alignments as ***,in many real-world applications,it is difficult to realign a large amount of parallel data for new scenarios due to the substantial labor costs,leading the non-parallel multi-modal data and existing methods cannot be used *** the other hand,there actually exists auxiliary parallel multi-modal data with similar semantics,which can assist the non-parallel data to learn the consistent ***,in this paper,we aim at“Alignment Efficient Image-Sentence Retrieval”(AEIR),which recurs to the auxiliary parallel image-sentence data as the source domain data,and takes the non-parallel data as the target domain *** single-modal transfer learning,AEIR learns consistent image-sentence cross-modal representations of target domain by transferring the alignments of existing parallel ***,AEIR learns the image-sentence consistent representations in source domain with parallel data,while transferring the alignment knowledge across domains by jointly optimizing a novel designed cross-domain cross-modal metric learning based constraint with intra-modal domain adversarial ***,we can effectively learn the consistent representations for target domain considering both the structure and semantic ***,extensive experiments on different transfer scenarios validate that AEIR can achieve better retrieval results comparing with the baselines.

关键词： image-sentence retrieval transfer learning semantic transfer structure transfer

Multi-UAV cooperative maneuver decision-making for pursuitevasion using improved MADRL

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Defence Technology（防务技术） 2024年第5期35卷 187-197页

作者： Delin Luo Zihao Fan Ziyi yang yang Xu School of Aerospace Engineering Xiamen UniversityXiamen 361102China School of Civil Aviation Northwestern Polytechnical UniversityXi'an 710072China

Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net network based on a communication mechanism is introduced into a deep reinforcement learning algorithm to solve the multi-agent problem. A layer of gated recurrent unit(GRU) is added to the actor-network structure to remember historical environmental states. Subsequently,another GRU is designed as a communication channel in the Comm Net core network layer to refine communication information between UAVs. Finally, the simulation results of the algorithm in two sets of scenarios are given, and the results show that the method has good effectiveness and applicability.

关键词： Reinforcement learning UAV Maneuver decision GRU Cooperative control

真核生物集缩素SMC2/SMC4异二聚体的结构解析研究进展

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中国细胞生物学学报 2018年第3期40卷 439-447页

作者：王洪振杨斯涵李桂英吉林师范大学生命科学学院四平136000 吉林大学分子酶学工程教育部重点实验室吉林大学生命科学学院长春130012

真核生物集缩素(condensin)的主要作用是在细胞周期过程中调控染色体的动态变化。它是一种含5个亚基的蛋白质,由1个起核心催化作用的SMC2(structure maintenance of chromosomes 2)/SMC4异二聚体和3个起调节作用的非SMC亚基组成。目前,... 详细信息

真核生物集缩素(condensin)的主要作用是在细胞周期过程中调控染色体的动态变化。它是一种含5个亚基的蛋白质,由1个起核心催化作用的SMC2(structure maintenance of chromosomes 2)/SMC4异二聚体和3个起调节作用的非SMC亚基组成。目前,关于集缩素中SMC2/SMC4异二聚体的体内构象和分子作用机制仍不清楚。最近,对SMC2/SMC4异二聚体的结构解析取得许多新进展。该文在简要介绍SMC蛋白的基本结构、真核生物集缩素的发现、真核生物集缩素的结构组成的基础上,对近年来SMC2/SMC4异二聚体的结构解析的研究进展作一综述,以期为相关研究提供参考。

关键词： SMC蛋白 SMC2/SMC4异二聚体集缩素结构解析