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Excessive gestational weight gain in early pregnancy and insufficient gestational weight gain in middle pregnancy increased risk of gestational diabetes mellitus

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Chinese Medical Journal 2022年第9期135卷 1057-1063页

作者： Aiqi Yin Fuying Tian Xiaoxia Wu Yixuan Chen kan liu Jianing Tong Xiaonian Guan Huafan Zhang Linlin Wu Jianmin Niu Department of Obsetics Shenchen Matemity and Chid Helthare HoptalThe First School of Cinial MedicneSouthem Medcal UnierityShenzhenGuangdong 518028China

Background:Gestational weight gain(GWG)is associated with the risk of gestational diabetes mellitus(GDM).However,the effect of weight gain in different trimesters on the risk of GDM is unclear.This study aimed to evaluate the effect of GWG on GDM during different trimesters.Methods:A birth cohort study was conducted from 2017 to 2020 in Shenzhen,China.In total,51,205 participants were included comprising two models(early pregnancy model and middle pregnancy model).Gestational weight(kg)was measured at each prenatal clinical visit using a standardized weight scale.Logistic regression analysis was used to assess the risk of GDM.Interaction analysis and mediation effect analysis were performed in the middle pregnancy model.Results:In the early pregnancy model,the risk of GDM was 0.858 times lower(95%confidence interval[CI]:0.786,0.937)with insufficient GWG(iGWG)and 1.201 times higher(95%CI:1.097,1.316)with excessive GWG after adjustment.In the middle pregnancy model,the risk of GDM associated with iGWG increased 1.595 times(95%CI:1.418,1.794)after adjustment;for excessive GWG,no significant difference was found(P=0.223).Interaction analysis showed no interaction between GWG in early pregnancy(GWG-E)and GWG in middle pregnancy(GWG-M)(F=1.268;P=0.280).The mediation effect analysis indicated that GWG-M plays a partial mediating role,with an effect proportion of 14.9%.Conclusions:eGWG-E and iGWG-M are associated with an increased risk of GDM.Strict control of weight gain in early pregnancy is needed,and sufficient nutrition should be provided in middle pregnancy.

关键词： Gestational diabetes mellitus Gestational weight gain Early pregnancy Middle pregnancy

Interface bond degradation and damage characteristics of full-length grouted rock bolt in tunnels with high temperature

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第10期15卷 2639-2657页

作者： Yunpeng Hu Mingming Zheng Wenkai Feng Jianjun Tong Yicheng Wang Qiling Wang kan liu Longzhen Ye State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China Key Laboratory of Geohazard Prevention of Hilly Mountains Ministry of Land and Resources(Fujian Key Laboratory of Geohazard Prevention)Fuzhou350116China School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China College of Civil Engineering Tongji UniversityShanghai200092China

Full-length grouted bolts play a crucial role in geotechnical engineering thanks to their excellent stability.However,few studies have been concerned with the degrading performance of grouted rock bolts caused by extensive and continuous heat conduction from surrounding rocks in high-geothermal tunnels buried more than 100 m(temperature from 28C to 100C).To investigate the damage mechanism,we examined the time-varying behaviors of grouted rock bolts in both constant and variable temperature curing environments and their damage due to the coupling effects of high temperature and humidity through mechanical and micro-feature tests,including uniaxial compression test,pull-out test,computed tomography(CT)scans,X-ray diffraction(XRD)test,thermogravimetric analysis(TGA),etc.,and further analyzed the relationship between grout properties and anchorage capability.In order to facilitate a rapid assessment and control of the anchorage performance of anchors in different conditions,results of the interface bond degradation tests were correlated to environment parameters based on the damage model of interfacial bond stress proposed.Accordingly,a thermal hazard classification criterion for anchorage design in high-geothermal tunnels was suggested.Based on the reported results,although high temperature accelerated the early-stage hydration reaction of grouting materials,it affected the distribution and quantity of hydration products by inhibiting hydration degree,thus causing mechanical damage to the anchorage system.There was a significant positive correlation between the strength of the grouting material and the anchoring force.Influenced by the changes in grout properties,three failure patterns of rock bolts typically existed.Applying a hot-wet curing regime results in less reduction in anchorage force compared to the hot-dry curing conditions.The findings of this study would contribute to the design and investigations of grouted rock bolts in high-geothermal tunnels.

关键词： High-geothermal tunnels Anchoring structure Coupling effect of temperature and humidity Bond degradation Interfacial damage mechanism

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基于层次标签结构的标记分布学习

数据分析与知识发现 2024年第2期8卷 44-55页

作者：刘勘游美琳卫兰茜中南财经政法大学信息与安全工程学院武汉430073 中国移动通信集团四川有限公司成都610041

【目的】考虑到标记分布学习中标记之间具有层次结构关系,将层次标签结构引入标记分布学习,提升标记分布学习的效果。【方法】提出一种基于层次标签结构的标记分布学习算法(Hierarchy Label Distribution Learning Algorithm,H-LDL),根... 详细信息

【目的】考虑到标记分布学习中标记之间具有层次结构关系,将层次标签结构引入标记分布学习,提升标记分布学习的效果。【方法】提出一种基于层次标签结构的标记分布学习算法(Hierarchy Label Distribution Learning Algorithm,H-LDL),根据样本在各层次的标签,利用条件概率描述粗、细两个层次的结构关系,并通过层次加权损失函数及其优化策略调节层次间标记的准确分布。【结果】在两个公开数据集上进行实验,用了5个指标进行效果检测,其中,BU_3DFE数据集在Euclidean、Squared、K-L指标中较基线算法最低值分别降低了3.99%、1.07%、3.10%,Intersec和Fidelity指标较基线算法最高值分别提升了4.24%、0.67%,COMP数据集在Euclidean指标上降低了0.48%,在Squared、K-L指标未见明显降低,在Intersec和Fidelity指标上提升了0.45%、0.02%。【局限】仅考虑了标签之间粗层次和细层次两层结构关系,当标签具有其他更复杂的层次结构关系时需进一步研究。【结论】加入层次标签结构后标记分布误差有明显减小,有效提升了标记分布学习的效果。

关键词：层次结构标记分布学习层次标签条件概率

The role of intraoperative electron radiotherapy in centrally located hepatocellular carcinomas treated with narrow-margin (<1 cm) hepatectomy: a prospective, phase 2 study

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Hepatobiliary Surgery and Nutrition 2022年第4期11卷 515-529,I0004页

作者： Liming Wang Yunhe liu Weiqi Rong Fan Wu Weibo Yu kan liu Shengtao Lin Yiling Zheng Kai Zhang Tana Siqin Changcheng Tao Mei liu Bo Chen Qinfu Feng Jianxiong Wu Department of Hepatobiliary Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Head and Neck Surgical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Pathology and Laboratory Medicine David Geffen School of MedicineUniversity of California at Los AngelesLos AngelesCAUSA Department of Diagnostic Radiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Surgical Oncology Fujian Provincial Hospital/Shengli Clinical Medical College of Fujian Medical UniversityFuzhouChina Laboratory of Cell and Molecular Biology&State Key Laboratory of Molecular Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background: Postoperative radiotherapy (RT) is known to play an important role in the treatment of hepatocellular carcinomas (HCCs), but the specific role of intraoperative electron radiotherapy (IOERT) in HCCs remains unclear. The aim of this study was to investigate the safety and efficacy of IOERT in centrally located HCCs treated with narrow-margin (<1 cm) hepatectomy. Methods: This was a single-center, phase 2, prospective non-randomized controlled study, including 268 patients with centrally located HCCs who underwent narrow-margin hepatectomy. The patients were subsequently allocated to the IOERT group (n=59) or to the control group (n=65). The primary outcome of the study was to compare recurrence-free survival (RFS) between the IOERT group and the control group, and the secondary outcome was to compare overall survival (OS) rate between the two groups. Results: Of 268 patients enrolled, a total of 124 were included in the study: 59 in IOERT group, 65 in control group. The 1-, 2-, 3-year RFS rates were 79.3%, 62.1% and 45.8% for patients in the IOERT group, and 47.6%, 28.6%, and 22.9% for patients in the control group, respectively (P=0.025). The 1-, 2-, and 3-year OS rates were 100.0%, 94.9%, and 83.7% for patients in the IOERT group, and 92.3%, 87.5%, and 79.4% for patients in the control group, respectively (P=0.314). Subgroup analysis of MVI (+) patients revealed that RFS and OS are significantly prolonged in the IOERT subgroup as compared to the control, whereas there was no significant difference of RFS and OS between the two groups in MVI (−) patients. Conclusions: IOERT for centrally located HCCs with concurrent narrow-margin hepatectomy was feasible and safe. Statistically better RFS rate was observed in the IOERT group compared to the control group. Subgroup analysis revealed that IOERT was more beneficial for postoperative survival of HCC patients with MVI. Trial Registration: ChiCTR-TRC-12002802;www.***.int/ictrp.

关键词： Hepatocellular carcinoma(HCC) intraoperative electron radiotherapy(IOERT) microvascular invasion(MVI) relapse survival overall survival(OS)

迎风角对跳台滑雪运动员飞行气动性能影响的研究

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工程力学 2024年第S1期41卷 339-345页

作者：王泽远刘衎柳方园魏宏伟刘庆宽石家庄铁道大学土木工程学院石家庄050043 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043 河北省风工程和风能利用工程技术创新中心石家庄050043

以探究迎风角对跳台滑雪运动员与滑雪板组成的多体系统的飞行气动性能的影响为目的,采用CFD数值模拟方法,在风速为29 m/s情况下,研究了多体系统迎风角为15°、20°、25°、30°、35°、40°六种情况下的气动性能变化情况。并在保证跳台... 详细信息

以探究迎风角对跳台滑雪运动员与滑雪板组成的多体系统的飞行气动性能的影响为目的,采用CFD数值模拟方法,在风速为29 m/s情况下,研究了多体系统迎风角为15°、20°、25°、30°、35°、40°六种情况下的气动性能变化情况。并在保证跳台滑雪运动员姿态以及飞行速度不变的情况下,以多体系统的升阻比作为衡量标准,对迎风角对多体系统气动性能的影响情况进行了评估。研究得出:多体系统升阻比随迎风角的增大呈递减趋势,且不同迎风角之间多体系统升阻比差异较大。在多体系统迎风角取为15°时,整个多体系统的升阻比取得最大值,有利于运动员取得良好的气动性能。此外,迎风角对跳台滑雪运动员气动性能影响的研究可为运动员比赛技巧相关的训练提供一定的指导作用。

关键词：跳台滑雪迎风角升阻比气动性能计算流体力学

Energy model based sensorless estimation method for operational temperature of braking resistor onboard metro vehicles

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Railway Sciences 2023年第4期2卷 470-485页

作者： Leiting Zhao kan liu Donghui liu Zheming Jin China Academy of Railway Sciences Corporation Limited Locomotive and Car Research InstituteBeijingChina AC Transmission Development Department Beijing Zongheng Electro-Mechanical Technologoly Co.LtdBeijingChina School of Electrical Engineering Beijing Jiaotong UniversityBeijingChina

Purpose–This study aims to improve the availability of regenerative braking for urban metro vehicles by introducing a sensorless operational temperature estimation method for the braking resistor(BR)onboard the vehicle,which overcomes the vulnerability of having conventional temperature sensor.Design/methodology/approach–In this study,the energy model based sensorless estimation method is developed.By analyzing the structure and the convection dissipation process of the BR onboard the vehicle,the energy-based operational temperature model of the BR and its cooling domain is established.By adopting Newton’s law of cooling and the law of conservation of energy,the energy and temperature dynamic of the BR can be stated.To minimize the use of all kinds of sensors(including both thermal and electrical),a novel regenerative braking power calculation method is proposed,which involves only the voltage of DC traction network and the duty cycle of the chopping circuit;both of them are available for the traction control unit(TCU)of the vehicle.By utilizing a real-time iterative calculation and updating the parameter of the energy model,the operational temperature of the BR can be obtained and monitored in a sensorless manner.Findings–In this study,a sensorless estimation/monitoring method of the operational temperature of BR is proposed.The results show that it is possible to utilize the existing electrical sensors that is mandatory for the traction unit’s operation to estimate the operational temperature of BR,instead of adding dedicated thermal sensors.The results also validate the effectiveness of the proposal is acceptable for the engineering practical.Originality/value–The proposal of this study provides novel concepts for the sensorless operational temperature monitoring of BR onboard rolling stocks.The proposed method only involves quasi-global electrical variable and the internal control signal within the TCU.

关键词： Operational temperature monitoring Braking resistor Regenerative braking Energy model Convection dissipation of heat

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适用于申威众核架构的稀疏矩阵-矩阵乘法

计算物理 2024年第1期41卷 22-32页

作者：刘侃杨磊薛巍陈文光清华大学计算机科学与技术系北京100084 国家超级计算无锡中心江苏无锡214000

本文提出新一代申威众核架构上稀疏通用矩阵-矩阵乘法(SpGEMM)的并行算法swSpGEMM。设计轻量级并行任务划分有效地应对了矩阵非零元分布引起的负载不均衡问题;针对累加过程中的不规则访存和指令流水低效问题,设计了分层稀疏累加器,在不... 详细信息

本文提出新一代申威众核架构上稀疏通用矩阵-矩阵乘法(SpGEMM)的并行算法swSpGEMM。设计轻量级并行任务划分有效地应对了矩阵非零元分布引起的负载不均衡问题;针对累加过程中的不规则访存和指令流水低效问题,设计了分层稀疏累加器,在不同输入特征下高效利用申威从核层次化内存,且减少了整数查找中的指令间依赖,更有效地发挥硬件的计算能力。SuiteSparse稀疏矩阵测试集中较大规模输入矩阵上,swSpGEMM的性能相比Intel Skylake双CPU上的MKL和NVIDIA A100上的cuSPARSE分别加速了21.1%和95.3%。

关键词：申威众核架构稀疏矩阵计算矩阵-矩阵乘法

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融媒体环境下广播播控的关键技术分析

信息与电脑 2024年第8期36卷 25-27页

作者：刘侃河南广播电视台河南郑州450008

在融媒体时代,广播电台正从传统广播向多元化传播模式转型,因而广播播控技术的研究和发展尤为重要。本文从广播电台和相关企业两个方面论述广播播控技术的重要性,提出不仅要运用高级数据分析技术实现精准个性化推荐,还要运用高级的广播... 详细信息

在融媒体时代,广播电台正从传统广播向多元化传播模式转型,因而广播播控技术的研究和发展尤为重要。本文从广播电台和相关企业两个方面论述广播播控技术的重要性,提出不仅要运用高级数据分析技术实现精准个性化推荐,还要运用高级的广播播控音频处理技术、流媒体技术和用户交互技术,以提高音频的质量和清晰度,实现多平台的同步播放,让用户参与到广播节目中来,从而提高用户体验和收听率。融媒体环境下采用个性化推荐、多平台同步播放、用户交互等广播播控的关键技术,以期能够为相关人员提供借鉴和参考。

关键词：融媒体广播播控关键技术流媒体

New Approach to Stability Analysis and Stabilization of Discrete-Time T-S Fuzzy Descriptor Systems

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 55-60页

作者： Mao Wang Jia Shi kan liu Space Control and Inertial Technology Research Center Harbin Institute of Technology

The problems of stability and state feedback control for a class of discrete-time T-S fuzzy descriptor systems are investigated in this paper. Based on fuzzy Lyapunov function,a set of slack variables is introduced to remove the basic semi-definite matrix inequality condition to check the regularity,causality and stability of discrete-time T-S fuzzy descriptor systems; a new sufficient condition for the discrete-time T-S fuzzy descriptor systems to be admissible is proposed in terms of strict linear matrix inequalities( LMIs). And a sufficient condition is proposed for the existence of state feedback controller in terms of a set of coupled strict LMIs.Finally,an illustrative example is presented to demonstrate the effectiveness of the proposed approach.

关键词： T-S fuzzy descriptor systems parameter uncertainties stability state feedback control linear matrix inequality(LMI)