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语言学知识驱动的空间语义理解能力评测数据集研究

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语言战略研究 2024年第5期9卷 7-21页

作者：詹卫东孙春晖肖力铭北京大学中文系北京100871

近20年来,深度学习技术显著提升了机器的自然语言处理能力,使之在诸多任务上接近甚至超过人类水平。机器学习的对象不再是直接来自人类语言学研究成果(知识),而是人类语言材料(数据)。在靠数据和算力驱动的大语言模型几近建成巴别塔的当... 详细信息

近20年来,深度学习技术显著提升了机器的自然语言处理能力,使之在诸多任务上接近甚至超过人类水平。机器学习的对象不再是直接来自人类语言学研究成果(知识),而是人类语言材料(数据)。在靠数据和算力驱动的大语言模型几近建成巴别塔的当下,语言学家通过深挖语言现象总结的语言学知识价值何在?本文提出从知识到数据的研究思路,设计了空间语义理解的6项任务:空间信息正误判别、异常空间信息识别、缺失参照成分补回、空间语义角色标注、空间表达异形同义判别、空间方位关系推理,以构建中文空间语义理解能力评测数据集为例,介绍从SpaCE2021到SpaCE2024数据集的设计思想、数据集制作概况以及机器在空间语义理解任务上的表现。总的来看,参加SpaCE赛事的大语言模型,在依赖表面分布特征(形式线索)的任务上容易获得好成绩,在依赖深层语义理解(认知能力)的任务上容易表现不好。因此,在人工智能高速发展使得语言学知识在计算机信息处理领域被动边缘化的当下,语言学知识的价值需要拓展,即用于指导小而精的高品质语言数据,以提升机器学习的效果和效率。为了计算应用的目的,语法研究应该在观察充分、描写充分、解释充分之上,追求更具挑战性的目标——生成充分。

关键词：人工智能大语言模型语言学知识空间语义理解数据合成

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依托多风格强化学习的车辆轨迹跟踪避撞控制

汽车工程 2024年第6期46卷 945-955页

作者：肖礼明张发旺陈良发闫昊琪马飞李升波段京良北京科技大学机械工程学院北京100083 北京理工大学机械与车辆学院北京100081 清华大学车辆与运载学院北京100084

轨迹跟踪避撞是车辆智能性的重要体现,针对现有控制方法面对同一场景的控制风格单一问题,本文中提出了一种多风格型强化学习控制方法。为实现控制风格多样性,首次将风格指标引入值网络和策略网络,搭建了多风格跟踪避撞策略网络,并结合... 详细信息

轨迹跟踪避撞是车辆智能性的重要体现,针对现有控制方法面对同一场景的控制风格单一问题,本文中提出了一种多风格型强化学习控制方法。为实现控制风格多样性,首次将风格指标引入值网络和策略网络,搭建了多风格跟踪避撞策略网络,并结合值分布强化学习理论构建了多风格策略迭代框架,依托该框架推导提出了多风格值分布强化学习算法。仿真和实车试验表明:所提出方法可以多种驾驶风格(激进、中性、保守)完成轨迹跟踪避撞任务,实车稳态轨迹跟踪误差小于5cm,具备较高的控制精度,实车平均单步决策耗时仅为6.07ms,满足实时性要求。

关键词：多风格值分布强化学习轨迹跟踪主动避撞

探讨瘢痕子宫再次妊娠经阴道分娩的可行性及安全性

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实用妇科内分泌电子杂志 2024年第15期11卷 37-39页

作者：李寅红季滢肖黎明如皋市人民医院妇产科江苏如皋226500

目的探讨瘢痕子宫再次妊娠经阴道分娩的可行性及安全性。方法选取80例瘢痕子宫再次妊娠分娩产妇,根据分娩方式不同分为观察组与对照组,每组40例。观察组选择经阴道试产,对照组选择剖宫产术。记录观察组产妇经阴道试产成功率,比较两组产... 详细信息

目的探讨瘢痕子宫再次妊娠经阴道分娩的可行性及安全性。方法选取80例瘢痕子宫再次妊娠分娩产妇,根据分娩方式不同分为观察组与对照组,每组40例。观察组选择经阴道试产,对照组选择剖宫产术。记录观察组产妇经阴道试产成功率,比较两组产妇产后出血量、住院时间及并发症发生情况。结果观察组产妇试产成功率为85.00%;观察组产妇产后出血量少于对照组,住院时间短于对照组(P<0.05)。观察组产妇并发症发生率显著低于对照组(P<0.05)。结论在严格遵循阴道分娩和剖宫产适应证的基础上,对瘢痕子宫产妇,经阴道试产具有可行性和安全性。

关键词：瘢痕子宫阴道分娩可行性安全性

剖宫产术后再次妊娠经阴道分娩的相关影响因素

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实用妇科内分泌电子杂志 2024年第5期11卷 18-20页

作者：季滢李寅红邹美林肖黎明如皋市人民医院妇产科江苏如皋226500

目的探讨剖宫产术后再次妊娠时经阴道分娩的影响因素。方法选取本院80例剖宫产后再次妊娠孕妇为研究对象,根据分娩方式不同划分为经阴道分娩组与剖宫产组,各40例。回顾性分析两组的基础资料,包含年龄、产次、孕前体质量指数、上次剖宫... 详细信息

目的探讨剖宫产术后再次妊娠时经阴道分娩的影响因素。方法选取本院80例剖宫产后再次妊娠孕妇为研究对象,根据分娩方式不同划分为经阴道分娩组与剖宫产组,各40例。回顾性分析两组的基础资料,包含年龄、产次、孕前体质量指数、上次剖宫产间隔时间等,总结分析剖宫产术后再次妊娠经阴道分娩的影响因素。结果多因素分析结果显示,年龄≤30岁、孕前体质量指数≤25kg/m²、上次剖宫产间隔时间>2年、子宫下段厚度>2mm、分娩前子宫颈Bishop评分>5分、有不良妊娠结局史是剖宫产术后再次妊娠经阴道分娩的影响因素(P<0.05)。结论年龄、孕前体质量指数、上次剖宫产间隔时间、子宫下段厚度、分娩前子宫颈Bishop评分、不良妊娠结局史是剖宫产术后再次妊娠经阴道分娩的影响因素,临床需要在分娩前高度重视,提前做好相关准备,以尽可能提高经阴道分娩成功率,改善母婴结局,提升分娩质量。

关键词：剖宫产手术再次妊娠经阴道分娩影响因素

ASYMPTOTIC ANALYSIS OF DYNAMIC PROBLEMS FOR LINEARLY ELASTIC SHELLS--JUSTIFICATION OF EQUATIONS FOR DYNAMIC FLEXURAL SHELLS

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Chinese Annals of Mathematics,Series B 2001年第3期22卷 13-22页

作者： xiao liming Institute of Mathematics Fudan University Shanghai 200433 China Department of Computer Science Guangdong Normal Polytechnic Guangzhou 510665 China

Under certain conditions, starting from the three-dimensional dynamic equations of elastic shells the author gives the justification of dynamic equations of flexural shells by means of the method of asymptotic analysis.

关键词：渐近分析动态方程线性弹性壳体有界域

New evidence for the epigenetic regulation of skeletal stem cells

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Science Bulletin 2024年第13期69卷 2004-2006页

作者： liming Zhao Jun xiao Charles K.F.Chan Institute for Stem Cell Biology and Regenerative Medicine Stanford University School of MedicineStanford CA 94305USA Department of Surgery Division of Plastic and Reconstructive SurgeryStanford University School of MedicineStanford CA 94305USA Department of Orthopaedic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Skeletal stem cells(SSCs)are crucial for skeletal development and regeneration,yet the epigenetic regulation of these cells remains poorly *** studies have delineated the epigenetic landscape across the developmental trajectory of SSCs,highlighting the involvement of Ptip in regulating SSC *** skeletal system undergoes dynamic remodeling throughout *** stem cells(SSCs),residing within the skeleton and lineage-restricted,serve as a cellular reserve to foster development and maintain skeletal *** categorized within the broader mesenchymal stromal/stem cells(MSCs).

关键词： skeletal involvement maintain

In situ formed Mg(BH_(4))_(2) for improving hydrolysis properties of MgH_(2)

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Journal of Magnesium and Alloys 2024年第3期12卷 1204-1214页

作者： Yongyang Zhu Mili Liu liming Zeng Yin Wang Daifeng Wu Rui Li Qing Zhou Renheng Tang Fangming xiao Institute of Resources Utilization and Rare Earth Development Guangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510641China

The hydrolysis of MgH_(2) delivers high hydrogen capacity(15.2 wt%),which is very attractive for real-time hydrogen ***,the formation of a surface passivation Mg(OH)_(2) layer and the large excess of H_(2)O required to ensure complete hydrolysis are two key challenges for the MgH_(2) hydrolysis ***,a low-cost method is reported to synthesize MgH_(2)@Mg(BH_(4))_(2) composite via ball-milling MgH_(2) with cheap and widely available B_(2)O_(3)(or B(OH)_(3)).By adding small amounts of B_(2)O_(3),the in-situ formed Mg(BH_(4))_(2) could significantly promote the hydrolysis of MgH_(2).In particular,the MgH_(2)–10 wt%B_(2)O_(3) composite releases 1330.7 mL·g^(−1) H_(2)(close to 80%theoretical hydrogen generation H_(2))in H_(2)O and 1520.4 mL·g^(−1) H_(2)(about 95%)in 0.5 M MgCl_(2) in 60 min at 26℃ with hydrolysis rate of 736.9 mL·g^(−1)·min^(−1) and 960.9 mL·g^(−1)·min^(−1) H_(2) during the first minute of the hydrolysis,*** addition,the MgCl_(2) solution allows repeated use by filtering and exhibits high cycle stability(20 cycles),therefore leading to much reduced capacity loss caused by the excess H_(2)*** show that by introducing B_(2)O_(3) and recycling the 0.5 M MgCl_(2) solution,the system hydrogen capacity can approach 5.9 wt%,providing a promising hydrogen generation scheme to supply hydrogen to the fuel cells.

关键词： Hydrolysis MgH_(2) Mg(BH_(4))_(2) Hydrogen generation B_(2)O_(3) MgCl_(2)

Energy Dissipation and Apparent Viscosity of Semi-solid Metal during Rheological Processes PartⅠ: Energy Dissipation

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Journal of Materials Science & Technology 2007年第6期23卷 342-346页

作者： Wen LIU Shuming XING Peiwei BAO Milan ZHANG liming xiao Beijing Jiaotong University Beijing 100044 China

This study investigated the rheological properties of semi-solid metal. An analytical model of apparent viscosity was built up based on analysis of energy dissipation during rheological processes such as slurry preparing, delivering and model filling. The rheological properties of SSM (semi-solid metal) slurry was described by an analytical model in terms of microstructural parameters, which consist of effective solid fraction, particle size and shape, and flow parameters such as mean velocity, fluctuant velocity and relative velocity between liquid and solid phase. The model was verified in the experiment of A356 alloys with a coaxial double-bucket rheometer. And the maximum relative error between the theoretical value and measured one is less than 10%. The results of experiment and theoretical calculation also indicate that the microstructural parameters and flow parameters are two major factors that affect the apparent viscosity of semi-solid alloys, and fluctuant velocity and relative velocity between liquid and solid phase are the key factors to distinguish between steady and transient rheological properties.

关键词： Semi-solid metal Energy dissipation Rheology Apparent viscosity Model

Design of process parameters for direct squeeze casting

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Journal of University of Science and Technology Beijing 2008年第3期15卷 339-343页

作者： Milan Zhang Shuming Xing liming xiao Peiwei Bao Wen Liu Qiao Xin Semisolid Forming Research Center Beijing Jiaotong University Beijing 100044 China Department of Mathematics lli Normal University Yining 835000 China

On the basis of the analysis of solidification interval and temperature distribution of components manufactured by the squeeze casting method, formulas for calculating the solidification interval and compaction pressure were deduced according to the principal request that the compaction pressure should be equal to or greater than the plastic deformation resistance of the forming component when solidification ended. The solidification interval was proven to be associated with many factors, such as weight of the component, specific heat of the alloy, latent heat, pouring temperature, component temperature at the end of solidification and heat-transfer coefficients. The compaction pressure was related to the strain rate, deformation temperature, and dimension of the de- forming component. The solidification interval and compaction pressure calculated by the formulas deduced in this article were adopted in the production of 45 steel bidirectional chapiter valves, and components with excellent oerformance were manufactured.

关键词： squeeze casting solidification time temperature distribution compaction pressure