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Special Issue on Future Digital Design and Manufacturing:Embracing Industry 4.0 and Beyond-Part Ⅱ

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1045-1046页

作者： Sheng-Feng Qin kai cheng School of Design Northumbria University College of Engineering Design and Physical SciencesBrunel University London

Digital design and manufacturing have been under pinned by digital modeling, simulation, and automation controls for decades. Under the new market requirement of mass customized products and services, the advancements in artificial intelligence （AI）, smart technology, virtual reality （VR）, big data, digital twin, robotics and human-centered design are becoming driving forces for the development of future digital design and manufacturing. This special issue focuses on the future digital design and manufacturing especially under the Industry 4.0 framework and beyond. This editorial introduces the papers in this special issue, which linked to the International Workshop on Digital Design and Manufacturing Technologies - Embracing Industry 4.0 and Beyond at Northumbria University in Newcastle, UK, held on 12-13 April 2016. In the Part I of the issue [1], there are 13 papers published in 2016, Vol- ume 29, No 6 of the Chinese Journal of Mechanical Engineering （this journal）.

关键词： Design In Special Issue on Future Digital Design and Manufacturing:Embracing Industry 4.0 and Beyond-Part

煤矿地面环境与荷载耦合作用下RC柱受压性能

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中国公路学报 2024年第4期37卷 263-273页

作者：李生元吕恒林吴元周周淑春彭浩孙呈凯中国矿业大学力学与土木工程学院江苏徐州221116 江苏建筑职业技术学院江苏建筑节能与建造技术协同创新中心江苏徐州221116

为了研究煤矿地面环境与荷载耦合作用下钢筋混凝土(Reinforced Concrete,RC)柱的受压性能,设计制作了14根大偏压RC柱试件,对试件分别进行了0、2、4、6、8、10、12个试验周期的煤矿地面环境与荷载耦合作用,分析了大偏压RC柱在煤矿地面环... 详细信息

为了研究煤矿地面环境与荷载耦合作用下钢筋混凝土(Reinforced Concrete,RC)柱的受压性能,设计制作了14根大偏压RC柱试件,对试件分别进行了0、2、4、6、8、10、12个试验周期的煤矿地面环境与荷载耦合作用,分析了大偏压RC柱在煤矿地面环境与荷载耦合作用下混凝土和钢筋的材料性能退化规律,探究了混凝土和钢筋的材料性能退化对柱受压性能的影响,给出了中、美、欧规范中煤矿地面环境与荷载耦合作用下矩形截面大偏心受压柱承载力计算的修正公式。研究结果表明:相比于单一的荷载作用,煤矿地面环境与荷载的耦合作用加剧了大偏压RC柱中混凝土和钢筋材料性能的退化;随着煤矿地面环境与荷载耦合作用时间的增加,大偏压RC柱混凝土的中性化深度线性增加但抗压强度逐渐降低,同时纵筋锈蚀率逐渐增加但屈服强度和极限强度线性降低,且纵筋屈服强度与锈蚀率呈负相关;煤矿地面环境与荷载耦合作用后RC大偏压柱承载力随作用时间的增加而降低,且屈服荷载和极限荷载均随纵筋锈蚀率增加而降低,通过引入煤矿地面环境与荷载耦合作用后混凝土和钢筋材料强度的退化系数,可以有效地修正中、美、欧规范中矩形截面大偏心受压柱承载力计算公式。

关键词：桥梁工程承载力计算方法试验研究 RC柱受压性能煤矿地面环境与荷载耦合作用

2017—2022年六安市基于乡镇尺度的流行性腮腺炎时空聚集性分析

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职业与健康 2024年第12期40卷 1641-1646页

作者：程凯秦伟王瑶潘璠六安市疾病预防控制中心急性传染病防治科

目的分析六安市基于乡镇尺度的流行性腮腺炎的流行特征及其时空聚集性,为精准防控提供数据支持。方法收集2017—2022年六安市139个乡镇街道的流行性腮腺炎监测数据,采用描述流行病学方法分析其流行特征。运用SaTScan9.6软件对监测数据... 详细信息

目的分析六安市基于乡镇尺度的流行性腮腺炎的流行特征及其时空聚集性,为精准防控提供数据支持。方法收集2017—2022年六安市139个乡镇街道的流行性腮腺炎监测数据,采用描述流行病学方法分析其流行特征。运用SaTScan9.6软件对监测数据进行时空扫描分析,探测其时间和空间聚集性;使用ArcGIS 10.7软件采用全局和局部空间自相关分析方法对监测数据进行分析。结果2017—2022年六安市共报告流腮病例4475例,年均发病率为12.73/10万,2019年发病率最高(20.81/10万),发病总体呈先上升后下降趋势。2020年以前呈季节性,春末夏初和冬季为高发季节,2021年后发病季节性不再明显。<15岁的学生和儿童为高风险人群,占总体病例数的77.16%。发病率居前3位的区县分别为金寨县(28.32/10万)、霍山县(20.79/10万)和叶集区(18.82/10万)。发病率位居前3位的乡镇分别为小华山街道(76.80/10万)、望城街道(68.69/10万)、太阳乡(64.93/10万)。2017—2022年流行性腮腺炎发病率均存在空间相关性,2017—2022年局部自相关分析显示,高-高聚集地区主要分布城北乡、三十铺镇、清水河街道、三里桥街道、东市街道、中市街道、鼓楼街道、望城街道、小华山街道、平桥乡、城南镇、中店乡、先生店乡、新安镇、韩摆渡镇、分路口镇,金寨县沙河乡、关庙乡、吴家店镇、古碑镇、果子园乡、天堂寨镇、青山镇以及霍山县上土市镇和太平畈乡,2019年分布范围最为广泛。时空扫描分析,共识别4个聚集区,一类聚集区是以市区东市街道为中心的12个乡镇,4个二类区域分别以金寨县和霍山县乡镇为核心,包括金寨县11个乡镇和霍山县2个乡镇;聚集时间在2018年10月到2019年4月。不同方法的空间聚集性具有相似性。结论2017—2022年六安市流行性腮腺炎发病率存在时间和空间聚集性,发病热点范围较为稳定,未来需要加强对主城区以及金寨县和霍山县部分乡镇进行针对性防控。

关键词：流行性腮腺炎空间自相关时空扫描分析时空聚集性流行特征

Disturbance during “Going into the Thick of Life”: Studies around Xu Guangyao Diary

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2019年第4期13卷 528-545页

作者： cheng kai Institute of Literature Chinese Academ y of Social SciencesBeijing 100732China

As the key principle in the literary and artistic world of the Mao Zedong era,“going into the thick of life”is far more than a mere approach to discovering material and themes for *** path of“going into the thick of life”set upon the premise of“diving deep into work”stems from the two principles established together in Mao Zedong’s“Talks at the Yan’an Forum on Literature and Art”(Zai Yan’cm wenyi zuotanhui shang de jianghua)and the rectification movement:reform of revolutionaries and intellectuals through“combination with the masses of workers,peasants and soldiers,”and second,reform of revolutionary politics via the“mass line,”designed to trigger the creativity of the *** of these two principles is the precondition of the *** the one hand,“going into the thick of life”based on the premise of“diving deep into work”offers the subjective perspective of the revolutionaries deeply involved in the local social reform-their difficulties,frustrations,and necessary self-adjustments when revolutionary ideals and the subjective attitudes towards policies conflicted with the realities of *** the other hand,different from official chronicles and local archives,records of their actions and real observations provide us with a sort of experiential perspective from the grass-roots level which appears more rich,complete and vivid,enabling us to view the problems of revolution from the perspective of the social system in operation,on top of the possibility of seeing the society from the subjective stance of *** detailed records of the 1953 cooperative establishment presented in Xu Guangyao riji(Xu Guangyao diary)offers us a fine example of a text about Agoing into the thick of life.^Despite the failure of his writing plan,all of the harassment and frustrations recorded in the diary possess special epistemological value,offering a clear-cut picture of the friction and interaction between the logic of real-life practice and the logic of action ba

关键词： going into the thick of life Xu Guangyao “Talks at the Yan’an Forum on Literature and Art”(Zai Yan’an wenyi zuotanhuf shang de jianghua)

碳和氧掺杂紫磷烯作为双极磁性半导体材料的理论预测

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物理学报 2024年第1期73卷 266-276页

作者：卢一林董盛杰崔方超张开成刘春梅李杰森毛卓渤海大学物理科学与技术学院渤海大学海洋研究院锦州121007 广东白云学院电气与信息工程学院广州510450 渤海大学食品科学与工程学院锦州121007 佛山科学技术学院环境与化学工程学院佛山528000 中国医学科学院北京协和医学院天津300192

紫磷烯是一种结构稳定且具有优异光电特性的新型二维材料,研究掺杂效应有助于理解其物理本质,对进一步开发纳米电子器件具有重要意义.本文采用基于密度泛函理论的第一性原理方法,研究了非金属元素B,C,N,O掺杂单层紫磷烯的电磁性质.计算... 详细信息

紫磷烯是一种结构稳定且具有优异光电特性的新型二维材料,研究掺杂效应有助于理解其物理本质,对进一步开发纳米电子器件具有重要意义.本文采用基于密度泛函理论的第一性原理方法,研究了非金属元素B,C,N,O掺杂单层紫磷烯的电磁性质.计算结果表明,B和N掺杂之后没有产生磁性,体系依旧表现为非磁性半导体;而C和O掺杂导致体系发生自旋劈裂,紫磷烯由非磁性半导体转变成为双极磁性半导体,其自旋密度主要分布在磷原子和间隙区域内而非杂原子上.电场调控氧掺杂紫磷烯可使其载流子的自旋极化方向发生反转,当施加一定大小的正向或反向的静电场时,能带色散程度变强,氧掺杂紫磷烯转变成100%自旋极化向下或向上的单自旋半金属磁体.基于氧掺杂紫磷烯材料设计的场效应自旋滤通器可利用改变门电压方向的方法实现电流自旋极化方向的反转,表明氧掺杂紫磷烯有望成为二维自旋场效应晶体管、双极磁性自旋电子学器件、双通道场效应自旋滤通器以及场效应自旋阀的理想候选材料.

关键词：紫磷烯掺杂双极磁性半导体单自旋半金属磁体

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一种计算变形套管通过能力的新方法

四川大学学报（自然科学版） 2024年第4期61卷 47-53页

作者：樊成凯周文高胡朝浪冯民富四川大学数学学院成都610064 中国石油集团川庆钻探工程有限公司成都610051

研究特定工具在变形套管中的可通过性对油气生产具有重要价值.本文研究了固定截面半径的工具在弯曲及变形井段套管中的最大可通过长度.基于多臂井径数据及钻井资料,本文构建了各深度点处截面的最大内切圆计算模型,并采用几何模型计算了... 详细信息

研究特定工具在变形套管中的可通过性对油气生产具有重要价值.本文研究了固定截面半径的工具在弯曲及变形井段套管中的最大可通过长度.基于多臂井径数据及钻井资料,本文构建了各深度点处截面的最大内切圆计算模型,并采用几何模型计算了变形套管的三维通过能力.对于多臂井径数据的处理,为解决最小二乘法计算精度不足及内切圆越界问题,本文提出了一种新的求解截面圆心及最大通径的模式迭代搜索法,并将其用于数据解释.算例结果表明,本文提出的方法虽然在计算效率上略低于最小二乘法,但有效降低了计算误差,并确保内切圆不会越界.本文的结果可望被用于提高油气生产效率.

关键词：水平井套管最大内切圆多臂井径仪可下入性

Flow field effect of delayed neutron precursors in liquid-fueled molten salt reactors

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Nuclear Science and Techniques 2022年第8期33卷 16-32页

作者： Xian-Di Zuo Mao-Song cheng Yu-Qing Dai kai-cheng Yu Zhi-Min Dai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

In molten salt reactors(MSRs),the liquid fuel salt circulates through the primary loop and a part of the delayed neutron precursors(DNPs)decays outside the reactor *** model and analyze the flow field effect of DNPs in channel-type liquid-fueled MSRs,a three-dimensional space-time dynamics code,named ThorCORE3D,that couples neutronics,core thermalhydraulics,and a molten salt loop system was developed and validated with the Molten Salt Reactor Experiment(MSRE)*** effects of external loop recirculation time,fuel flow rate,and core flow field distribution on the delayed neutron fraction loss of MSRE at steadystate were modeled and simulated using the ThorCORE3D ***,the flow field effect of the DNPs on the system responses of the MSRE in the reactivity insertion transient under different initial conditions was analyzed systematically for the channel-type liquid-fueled *** results indicate that the flow field condition has a significant effect on the steady-state delayed neutron fractions and will further affect the transient power and temperature responses of the reactor *** analysis results for the effect of the DNP flow field can provide important references for the design optimization and safety analysis of liquid-fueled MSRs.

关键词： Molten salt reactor Delayed neutron precursor Nodal expansion method Coupled neutronics and thermal-hydraulics

Study of Relation between EFL Students'Cognitive Style and Pragmatic Competence

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Journal of Electronic Science and Technology 2017年第1期15卷 41-47页

作者： kai-Wen cheng Yi Wang Hong-Mei Yan Key Laboratory for NeuroInformation of Ministry of Education University of Electronic Science and Technology of ChinaChengdu 610054China Zhejiang University Hangzhou 310058China

Individual difference is one of the important factors affecting the success of learning English as foreign language（EFL）. However, very little research has dabbled in the correlation between pragmatic competence and cognitive styles among college students. Two questionnaires（the embedded figure test and the pragmatic competence test） were designed and used to conduct our study among seniors with non-English majors from key universities. The data was analyzed with SPSS 21.0 and results showed that pragmatic competence of the subjects was much lower than expected. Besides, there was a significant and positive correlation between field dependent（FD）cognitive style and inter-language pragmatic competence while no significant correlation was found with field independent（FI）. A regression model was also formulated to obtain more specific information. Lastly,some practical advice is offered for teachers to boost students＇ pragmatic competence in the future with FD/FI cognitive styles into proper consideration.

关键词： competence pragmatic Competence Style majors college proficiency questionnaire affecting universities

Investigation on thermal characteristics and desensitization mechanism of improved step ladder-structured nitrocellulose

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Defence Technology（防务技术） 2023年第2期20卷 93-102页

作者： cheng-kai Pu Yu Luan Ming-jun Yi Zheng-gang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094People's Republic of China

Nitrocellulose,or cellulose nitrate,has received considerable interest due to its various applications,such as propellants,coating agents and gas ***,its high mechanical sensitivity caused many accidents during its storage and usage in *** this work,two kinds of insensitive step ladderstructured nitrocellulose(LNC)with different nitrogen contents were *** products were characterized by FT-IR,Raman,XRD,SEM,elemental analysis,TGA,DSC,accelerating rate calorimeter analysis(ARC),and drop weight test to study their molecular structure,thermal characteristics and desensitization *** with raw nitrocellulose,LNC has a sharper exothermic peak in the DSC and ARC *** H50values of the two kinds of LNC increased from 25.76 to 30.01 cm for low nitrogen content and from 18.02 to 21.84 cm for high nitrogen content,*** results show that the ladder-structure of LNC which provides regular molecular arrangement and a soft buffer made with polyethylene glycol could affect the energy releasing process of LNC and reduce the sensitivity of *** LNC provides an alternative to be used as a binder in insensitive propellants formulation.

关键词： Nitrocellulose Decomposition Desensitization Ladder structure Thermal characteristic Polyethylene glycol