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基于多阶段训练的跨语言摘要技术

信息工程大学学报 2024年第2期25卷 139-147页

作者：潘航宇席耀一周会娟陈刚郭志刚信息工程大学河南郑州450001

为解决跨语言摘要(Cross-Lingual Summarization,CLS)模型语义理解、跨语言对齐和文本生成能力不高的问题,提出了一个基于多阶段训练的英-中跨语言摘要模型。首先,进行多语言去噪预训练,同时学习中、英文的通用语言知识;其次,进行多语... 详细信息

为解决跨语言摘要(Cross-Lingual Summarization,CLS)模型语义理解、跨语言对齐和文本生成能力不高的问题,提出了一个基于多阶段训练的英-中跨语言摘要模型。首先,进行多语言去噪预训练,同时学习中、英文的通用语言知识;其次,进行多语言机器翻译微调,同时学习对英文的语义理解、从英文到中文的跨语言对齐以及中文的文本生成能力;最后,进行CLS微调,进一步学习特定于CLS任务的语义理解、跨语言对齐和文本生成能力,最终获得一个性能优异的英-中跨语言摘要模型。实验结果表明所提模型的CLS性能有明显提升,且多语言去噪预训练和多语言机器翻译均可提高模型性能。与众多基线模型中的最优性能相比,所提模型在英-中跨语言摘要基准集上将ROUGE-1、ROUGE-2和ROUGE-L值分别提升了45.70%、60.53%和43.57%。

关键词：跨语言摘要多阶段训练多语言去噪预训练多语言机器翻译

Negative Poisson’s ratio cable compensation support for 32 m super-large-span highway tunnel:A case study

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Underground Space 2024年第1期14卷 156-175页

作者： Aipeng guo Manchao He Songyuan Liu Zhifeng Du Zengwang Lyu zhigang Tao State Key Laboratory for Geomechanics and Deep Underground Engineering Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China Department of Civil and Mineral Engineering University of TorontoToronto M5S 1A4Canada State Key Laboratory for Geomechanics and Deep Underground Engineering Sanmenxia Research CenterHenan 472099China

Although super-large-span tunnels ensure convenient transportation,they face many support *** lack of normative construction guidance and the limited number of reference engineering cases pose a significant challenge to the stability control of superlarge-span *** on the geological conditions of a super-large-span tunnel(span=32.17 m)at the bifurcation section of the Shenzhen interchange,this study determined support parameters via theoretical calculation,numerical simulation,and engineering *** support effects of negative Poisson’s ratio(NPR)anchor cables and ordinary anchor cables on super-long-span tunnels were simulated and ***,based on FLAC3D simulations,the surrounding rock stress field of NPR anchor cables was analyzed under different prestressing conditions,and the mechanism of a long-short combination,high-prestress compensation NPR anchor cable support was *** the basis of numerical simulations,to our knowledge,the three-dimensional(3D)geomechanical model test of the NPR anchor cable and ordinary anchor cable support for super-large-span tunnel excavation is conducted for the first time,revealing the stress evolution law of super-large-span tunnels,deformation and failure characteristics of the surrounding rock,and the changing trend of the anchor cable’s axial force,and verifies that NPR anchor cables with high preloads are suitable for super-large-span tunnel support and have advantages over ordinary anchor *** study can provide a reliable theoretical reference for the support design and stability control of the surrounding rock of similar shallow-buried super-large-span tunnels.

关键词： Super-large-span tunnel Negative Poisson’s ratio(NPR)anchor cable Excavation compensation method Numerical simulation Geomechanical model test

Flow Behavior and Microstructures of Inconel 625 Superalloy at the Elevated Temperature

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稀有金属材料与工程 2011年第S3期40卷 95-98页

作者： Li Defu, guo Shengli, Wu zhigang, Zou Honghui, Pen Haijian General Research Institute for Nonferrous Metals, Beijing 100088, China Gen Res Inst Nonferrous Met Beijing 100088 Peoples R China

The deformation behavior of Inconel 625 superalloy was investigated by means of hot compression tests. The flow stress curves were obtained in the temperature and strain rate ranges of 950-1200 ℃ and 0.01-10 s-1, respectively. Optical microscopy was used to evaluate the microstructural evolution of the alloy under different conditions examined. The results show that the flow stress decreases with decreasing strain rate and increasing temperature, and the activation energy is about 654.502 kJ/mol. Microstructure observations show that with increasing temperature, the sizes and volume fraction of dynamic recrystallization (DRX) grains increase. The strain has no remarkably effect on the sizes of DRX grains, but with increasing strain the volume fraction of DRX grains increases. During hot compression of Inconel 625 superalloy at elevated temperature, the occurrence of DRX was the main softening mechanism. The DRX mechanism of Inconel 625 superalloy can be mainly attributed to the discontinuous dynamic recrystallization (DDRX).

关键词： inconel 625 superalloy hot deformation flow stress dynamic recrystallization

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浅谈建筑机械租赁企业后场对现场的促进作用

建筑机械化 2024年第8期45卷 9-11页

作者：刘文华韩俊虎王善科郭志刚王文峰山东中建物资设备有限公司山东济南250014

介绍了塔机租赁企业后场的选择、功能要求、后场的硬件投入、流程管理、技术管理、现实意义、实训营服务等,主要阐述了通过后场资源配置与管理提升解决现阶段建筑机械租赁企业现场管理的窘境,通过加强后场的人员、物资管理,制定统一的... 详细信息

介绍了塔机租赁企业后场的选择、功能要求、后场的硬件投入、流程管理、技术管理、现实意义、实训营服务等,主要阐述了通过后场资源配置与管理提升解决现阶段建筑机械租赁企业现场管理的窘境,通过加强后场的人员、物资管理,制定统一的出场标准,从而减轻施工现场的维修保养强度,保证设备一直处于正常的运转状态,同时借助后场的资源优势强化各级管理的专业培训,开展实训营服务,有的放矢地管理现场的设备,为项目总包和企业创造最大的价值,同时也为建筑机械租赁行业提供一种新的发展模式。

关键词：建筑机械租赁企业塔式起重机后场现场实训营

停留皮下引流管预防肥胖患者急诊剖腹探查术后切口感染140例分析

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中华普通外科学文献（电子版） 2024年第1期18卷 34-38页

作者：黄跃明古晨杨志锋郭志刚王尧雒洪志广东省中山市人民医院普外三科 528400 广东省中山市人民医院手术麻醉一科 528400 西藏自治区工布江达县人民医院外科林芝860200

目的探讨停留皮下引流管在预防肥胖患者行急诊剖腹探查术后切口感染的价值。方法回顾性分析2021年7月至2023年6月期间广东省中山市人民医院普外三科和西藏自治区工布江达县人民医院外科收治的140例行急诊剖腹探查术肥胖患者,根据术中有... 详细信息

目的探讨停留皮下引流管在预防肥胖患者行急诊剖腹探查术后切口感染的价值。方法回顾性分析2021年7月至2023年6月期间广东省中山市人民医院普外三科和西藏自治区工布江达县人民医院外科收治的140例行急诊剖腹探查术肥胖患者,根据术中有无放置切口皮下引流管分为引流管组和对照组,观察并分析两组患者术后切口愈合情况、围手术期及随访情况等资料。结果两组患者在基线临床资料方面比较差异无统计学意义,引流管组在切口一期愈合率(χ^(2)=5.221,P=0.035)、14 d切口愈合率(χ^(2)=5.082,P=0.032)、切口愈合时间(t=2.917,P=0.040)、拆线时间(t=3.279,P<0.001)优于对照组,而在切口脂肪液化/渗液(χ^(2)=12.443,P<0.001)、切口感染率(χ^(2)=5.347,P=0.025)、二次缝合率(χ^(2)=4.674,P=0.036)均低于对照组,且提高了患者的住院满意度(t=5.221,P=0.045),差异均有统计学意义。结论在肥胖患者急诊剖腹探查术切口停留皮下引流管可有效预防切口感染,值得临床推广应用。

关键词：引流管肥胖患者剖腹探查术切口感染

Network Virtualization Based Seamless Networking Scheme for Fiber-Wireless （FiWi） Networks

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China Communications 2014年第5期11卷 1-16页

作者： DAI Qinglong ZOU Jianfeng SHOU guochu HU Yihong guo zhigang Beijing Laboratory of Network System Architecture and Convergence School of Information and Communication EngineeringBeij ing University of Posts and Telecommunications Beijing 100876 China

In order to reduce cost and complexity,fiber-wireless(FiWi) networks emerge,combining the huge amount of available bandwidth of fiber networks and the flexibility,mobility of wireless ***,there is still a long way to go before taking fiber and wireless systems as fully integrated *** this paper,we propose a network visualization based seamless networking scheme for FiWi networks,including hierarchical model,service model,service implementation and dynamic bandwidth assignment(DBA).Then,we evaluate the performance changes after network virtualization is *** for nodes,bandwidth for links and overheads leaded by network virtualization are *** performance of our proposed networking scheme is evaluated by simulation and real implementations,*** results show that,compared to traditional networking scheme,our scheme has a better performance.

关键词： fiber-wireless networks network virtualization service future network

The lowest fertility rates in the world?Evidence from the 2015 Chinese 1% sample census

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China Population and Development Studies 2019年第1期2卷 245-258页

作者： zhigang guo Stuart Gietel-Basten Baochang Gu Department of Sociology Peking UniversityBeijingPeople’s Republic of China Division of Social Sciences The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARPeople’s Republic of China Center for Population and Development Studies Renmin University of ChinaBeijingPeople’s Republic of China

As the world’s largest population,the total fertility rate(TFR)of China is of global ***,the introduction of recent reforms designed to lessen restrictions on childbearing have received wide *** well as outlining the fertility rate in China as derived from the 20151%sample census,in this short paper we seek to explore the impact of the 2013 reforms to fertility policy which allowed millions of eligible couples to bear a second *** performed standard demographic analysis on the 20151%sample census to calculate both TFR and parity-specific fertility rates for both the total population and specific *** overall national TFR from the census was calculated to be 1.047(down from 1.188 in 2010).TFR in urban areas was 0.914 compared to 1.265 in rural *** among migrant women was 0.896 compared to 1.115 for *** a modest increase in second-births can be identified,a decline in first birth rates offsets *** allowing for a generous margin of error,China’s fertility rates appear to be extremely low and declining *** impact of the recent reforms appears muted,especially in the face of declining first birth *** TFRs as calculated from the mini-census would be the lowest national rates in the *** research is required to triangulate these findings from other *** impact of the two-child policy may be muted.

关键词： China Fertility Census Marriage Parity Marriage age

Tree allometry responses to competition and complementarity in mixed-species plantations of Betula alnoides

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Forest Ecosystems 2024年第4期11卷 469-479页

作者： Boyao Chen Kaili Liu Chunsheng Wang Junjie guo Junkun Lu Lin Chen zhigang Zhao Jie Zeng Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou510520China Central South University of Forestry&Technology Changsha410004China Experimental Center of Tropical Forestry Chinese Academy of ForestryPingxiang532600China Nanjing Forestry University Nanjing210037China

Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species ***,the responses of tree allometry to resource utilisation within the framework of interspecific competition and complementarity remain poorly *** into consideration strong-and weakspace competition(SC and WC),as well as N_(2)-fixing and non-N_(2)-fixing tree species(FN and nFN),a mixedspecies planting trial was conducted for Betula alnoides,a pioneer tree species,which was separately mixed with Acacia melanoxylon(SC+FN),Erythrophleum fordii(WC+FN),Eucalyptus cloeziana(SC+nFN)and Pinus kesiya ***(WC+nFN)in southern *** years after planting,tree growth,total nitrogen(N)and carbon(C)contents,and the natural abundances of^(15)N and^(13)C in the leaves were measured for each species,and the mycorrhizal colonisation rates of *** were investigated under each *** variations and their relationships with space competition and nutrient-related factors were *** results showed a consistent effect of space competition on the height-diameter relationship of *** in mixtures with FN or *** tree height growth of *** was significantly promoted under high space competition,and growth in diameter at breast height(DBH),tree height and crown size were all expedited in mixtures with *** symbiotic relationship between ectomycorrhizal fungi and *** was significantly influenced by both space competition and N_(2) fixation by the accompanying tree species,whereas such significant effects were absent for arbuscular mycorrhizal ***,high space competition significantly decreased the water use efficiency(WUE)of ***,and its N use efficiency(NUE)was much lower in the FN *** equation modeling further demonstrated that the stem allometry of *** was affected by its NUE and WUE via changes in its height growth,and crown allometry was influ

关键词： Allometric relationship Resources competition and complementarity Mixed-species forest Tree-fungal symbiotic relationship N_2-fixing tree species Resource utilisation strategies

SUMO-1 modification of FEN1 facilitates its interaction with Rad9-Radl-Husl to counteract DNA replication stress

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Journal of Molecular Cell Biology 2018年第5期10卷 460-474页

作者： Xiaoli Xu Rongyi Shi Li Zheng zhigang guo Liangyan Wang Mian Zhou Ye Zhao Bing Tian Khue Truong Yuan Chen Binghui Shen Yuejin Hua Hong Xu Institute of Nuclear-Agricultural Sciences Zhejiang University Hangzhou 310029 China Department of Cancer Genetics and Epigenetics City of Hope National Medical Center and Beckman Research Institute Duarte CA 91010 USA Jiangsu Key Laboratory for Molecular and Medical Biotechnology and College of Life Sciences Nanjing Normal University Nanjing 210046 China Department of Molecular Medicine City of Hope National Medical Center and Beckman Research Institute Duarte CA 91010 USA

Human flap endonuclease 1 （FEN1） is a structure-specific, multi-functional endonuclease essential for DNA replication and repair. We and others have shown that during DNA replication, FEN1 processes Okazaki fragments via its interaction with the proliferating cell nuclear antigen （PCNA）. Alternatively, in response to DNA damage, FEN1 interacts with the PCNA-like Radg-Radl-Husl complex instead of PCNA to engage in DNA repair activities, such as homology-directed repair of stalled DNA replication forks. However, it is unclear how FEN1 is able to switch between these interactions and its roles in DNA replication and DNA repair. Here, we report that FEN1 undergoes SUMOylation by SUMO-1 in response to DNA replication fork-staUing agents, such as UV irradiation, hydroxyurea, and mitomycin C. This DNA damage-induced SUMO-1 modification promotes the interaction of FEN1 with the Radg-Rad1-Husl complex. Furthermore, we found that FEN1 mutations that prevent its SUMO-1 modification also impair its ability to interact with HUS1 and to rescue stalled replication forks. These impairments lead to the accumulation of DNA damage and heightened sensitivity to fork-staUing agents. Altogether, our findings suggest an important role of the SUMO-1 modification of FEN1 in regulating its roles in DNA replication and repair.

关键词： flap endonuclease 1 Rad9-Rad1-Hus1 complex replication stress SUMOylation