检索结果-南通市图书馆

Truss-type maintenance devices and corresponding pipeline lifting control strategies

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2021年第3期18卷 939-950页

作者： Tian-Feng zhao qing-Yuan Zhang gui Chu College of Safety and Ocean Engineering China University of Petroleum-BeijingBeijing 102249China China Huanqiu Contracting and Engineering(Beijing)CO. Ltd.Beijing 100012China

For new submarine pipeline maintenance lifting equipment,a specialized analysis model is constructed in this study.A pipeline can be divided into the lifted portion and the touch-down portion that lies on the seabed,and each of these portions can be analyzed separately by converting the continuity conditions at the touch-down points to boundary *** typical two-point sequence secant iterative technique is used to obtain the unknown lifted length and determine pipeline lifting *** BVP4C module in MATLAB software is used to solve this multiple-point boundary value problem issued from frst-order diferential ***,the triple-point lifting mode of truncated maintenance and the two-point lifting mode of online maintenance are *** the lifted heights at truss positions are shown,the lifting deformation,lifting forces,bending moment distribution,and axial force distribution can be analyzed using a dedicated analysis *** results can then be used to design a lifting strategy to protect the pipeline.

关键词： Pipeline lifting Multiple-point boundary value Shooting method Coulomb friction BVP4C module

大理州2016年脊髓灰质炎野病毒输入与传播风险评估

在线全文

学校读者我要写书评

暂无评论

中国公共卫生管理 2018年第5期34卷 698-700,704页

作者：何左杨晓炜李鸿钧易寿生赵桂芬赵清杉大理州疾病预防控制中心云南大理651000

目的对大理州脊髓灰质炎野病毒输入与传播风险进行评估,识别风险薄弱地区和环节,为科学制定防控措施,阻止脊灰疫情输入与传播提供参考依据。方法在《云南省2016年脊髓灰质炎野病毒输入与传播风险评估方案》的基础上,通过专家会商法及查... 详细信息

目的对大理州脊髓灰质炎野病毒输入与传播风险进行评估,识别风险薄弱地区和环节,为科学制定防控措施,阻止脊灰疫情输入与传播提供参考依据。方法在《云南省2016年脊髓灰质炎野病毒输入与传播风险评估方案》的基础上,通过专家会商法及查阅文献后改良部分评估指标,根据收集整理的资料,对人群免疫情况、AFP病例监测和境外输入风险进行评分,再乘以相应的权重系数,累加得到各县市的综合评分,依据综合评分以四分位数法判定风险等级。结果南涧县、大理市和巍山县为高风险;云龙等6个县为中风险;漾濞等3个县为低风险。结论各县市尤其是高风险地区,应根据薄弱环节采取针对性措施,加强常规免疫工作,提高人群免疫水平;加强AFP病例监测敏感性和质量;适时开展应急演练、提升疫情应对能力;加强宣传教育工作,巩固无脊灰状态。

关键词：脊髓灰质炎野病毒输入传播风险评估

Relationship　between　global　seismicity　and　solar　activities

在线全文

学校读者我要写书评

暂无评论

Acta Seismologica Sinica(English Edition) 1998年第4期11卷 495-500页

作者： gui-qing Zhang Beijing Astronomical Observatory Chinese Academy of Science Beijing China

ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｇｌｏｂａｌｓｅｉｓｍｉｃｉｔｙａｎｄｓｏｌａｒａｃｔｉｖｉｔｉｅｓＧＵＩ－ＱＩＮＧＺＨＡＮＧ（张桂清）ＢｅｉｊｉｎｇＡｓｔｒｏｎｏｍｉｃａｌＯｂｓｅｒｖａｔｏｒｙ，Ｃｈｉｎｅｓ... 详细信息

ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｇｌｏｂａｌｓｅｉｓｍｉｃｉｔｙａｎｄｓｏｌａｒａｃｔｉｖｉｔｉｅｓＧＵＩ－ＱＩＮＧＺＨＡＮＧ（张桂清）ＢｅｉｊｉｎｇＡｓｔｒｏｎｏｍｉｃａｌＯｂｓｅｒｖａｔｏｒｙ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅ...

关键词： Solar activity Solar proton events Solar radio flux Sunspot numbers

CT local reconstruction of solid rocket motor based on PI-POCS-TVM

在线全文

学校读者我要写书评

暂无评论

航空动力学报 2017年第2期32卷 470-476页

作者： LU Hong-yi CHEN qing-gui ZHU Min LI Peng zhao Ru-yan WANG Bin Airborne Vehicle Engineering Department Naval Aeronautical and Astronautical University Yantai Shandong 264001 China qingdao Branch Naval Aeronautical and Astronautical University Qingdao Shandong 266041 China No. 7 Department Naval Aeronautical and Astronautical University Yantai Shanctong 264001 China

In order to test the defects of solid rocket motor(SRM)accurately and efficiently,the computed tomography(CT)inspection scheme for SRM's defects was investigated and a CT local reconstruction algorithm called prior information-projection onto convex sets-total variation minimization(PI-POCS-TVM)was *** SRM was first inspected by industrial CT(ICT)to generate a low-resolution SRM image used as the prior information,then high-resolution local inspection was carried out for SRM's *** validate the effectiveness of the CT inspection scheme for SRM's defects,one SRM was inspected by a narrow fan beam ICT *** back projection(FBP)algorithm,POCS,POCS-TVM and PI-POCS-TVM algorithms were applied to reconstruct CT *** performance of these algorithms was also *** demonstrated the effectiveness of the CT inspection scheme for SRM's ***,the PI-POCS-TVM algorithm has better local reconstruction image quality than the other three algorithms,showing great significance for accurate measurement of SRM's defects.

关键词： interior tomography exterior tomography compressed sensing prior information projection onto convex sets-total variation minimization(POCS-TVM) solid rocket motor

Dynamics of a prestressed Timoshenko beam subject to arbitrary external load

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第11期11卷 898-907页

作者： Ji-qing JIANG gui-ru YE Department of Civil Engineering Zhejiang University Hangzhou 310058 China

The free vibration and transient wave in a prestressed Rayleigh-Timoshenko beam subject to arbitrary transverse forces are analyzed by the newly developed method of reverberation-ray matrix (MRRM). The effects of shear deformation and rotational inertia are taken into consideration. With a Fourier transform technique, the general wave solutions with two sets of unknown amplitude coefficients are obtained in the transformed domain for an unbonded prestressed beam under the action of arbitrary external excitations. From the coupling at joints and the compatibility of displacements in each member, the free and forced vibration responses of a beam with various boundary conditions are finally evaluated through certain numerical algorithms. Results are presented for a simply-supported beam subject to either a point fixed load or moving load. Good agreement with the finite element method (FEM) is obtained. The present work is instructive for high-speed railway bridge design and structural health monitoring.

关键词： Reverberation-ray analysis Prestressed Timoshenko beam Free vibration Dynamic responses

军民融合、产业协同集聚与区域创新绩效———基于交互作用与空间溢出效应的检验

在线全文

学校读者我要写书评

暂无评论

湖北科技学院学报 2025年第1期45卷 34-42页

作者：赵庆吴伟国务院国资委中国大连高级经理学院辽宁大连116086 大连交通大学机车学院辽宁大连116028

基于空间数据分析方法,分析军民融合、产业协同集聚和区域创新绩效在我国省际间分布格局,结果显示三者均存在显著的空间自相关性即空间溢出效应,并在局部地区形成了不同的集聚区域,存在高低集聚“俱乐部”现象。基于空间计量模型、实证... 详细信息

基于空间数据分析方法,分析军民融合、产业协同集聚和区域创新绩效在我国省际间分布格局,结果显示三者均存在显著的空间自相关性即空间溢出效应,并在局部地区形成了不同的集聚区域,存在高低集聚“俱乐部”现象。基于空间计量模型、实证检验军民融合、产业协同集聚对区域创新绩效的影响,得出主要结论:全国范围军民融合、产业协同集聚均对区域创新绩效具有显著的促进作用,但西部地区军民融合影响的效果最大,而东部地区则产业协同集聚影响的效果最大;同时,在全国范围内二者间具有较强的交互作用,并且在对有限的创新生产要素资源抢占作用下,二者呈现出替代效应,交互作用下对区域创新绩效产生抑制作用,东部、中部地区亦是如此,而在西部地区,二者呈现出互补效应,交互作用下对区域创新绩效产生促进作用;并对影响区域创新绩效的其他因素进行了分析。

关键词：军民融合产业协同集聚区域创新交互作用空间溢出效应

Diversity of Growth Habits and Their Association with VRN Allele of 81 American Wheat Lines

维普期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2010年第12期9卷 1705-1712页

作者： JI gui-su BAI gui-hua ZHANG qing-jiang Millet Crops Institute/National Millet Crops improvement Center Hebei Academy of Agricultural ＆ Forestry Sciences Shijiazhuang 050031 P.R. China Plant Science and Entomology Research Unit USDA-ARS/Kansas State University Manhattan KS 66503 USA

Eighty-one wheat accessions including 50 southern regional performance nursery （SRPN） lines and 31 northern regional performance nursery （NRPN） lines from the United States were tested to evaluate the growth habit by chilling treatments and to estimate the VRN allele variation with 19 pairs of published VRN primers. Two spring wheat accessions and 44 semi-spring wheat accessions were confirmed based on their chilling days＇ requirement and polymorphism was found at VRN loci. The Vrn-A1 allele had the highest frequency in the RPN accessions and VA1-CAPs markers identified growth habit of RPN lines. No polymorphism was found at the VRN3 loci and some polymorphism at the region of promoter and the first intron of VRN1 was not always consistent to growth habit in the wheat RPN accessions. The existence of variation in VRN alleles suggested that singly using the dominant Vrn allele is possible to extend the diversity of wheat accessions and improve their adaption to different environments in autumn-sowing region. This information will be useful for the cultivars exploitation and wheat breeding program.

关键词： wheat growth habit identification VRN allele diversity

Heading constraint algorithm for foot-mounted PNS using low-cost IMU

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2022年第3期33卷 727-736页

作者： gui Jing zhao Heming XU Xiang School of Electronic and Information Engineering Soochow UniversitySuzhou 215006China

Foot-mounted pedestrian navigation system(PNS)is a common solution to pedestrian navigation using micro-electro mechanical system(MEMS)inertial *** inherent problems of inertial navigation system(INS)by the traditional algorithm,such as the accumulated errors and the lack of observation of heading and altitude information,have become obstacles to the application and development of the *** this paper,we introduce a heuristic heading constraint *** of all,according to the movement characteristics of human gait,we use the generalized likelihood ratio test(GLRT)detector and introduce a time threshold to classify the human gait,so that we can effectively identify the stationary state of the *** addition,based on zero velocity update(ZUPT)and zero angular rate update(ZARU),the cumulative error of the inertial measurement unit(IMU)is limited and corrected,and then a heuristic heading estimation is used to constrain and correct the heading of the *** simulation and experiments with low-cost IMU,the method is proved to reduce the localization error of end-point to less than 1%of the total distance,and it has great value in application.

关键词： pedestrian navigation system(PNS) zero velocity update(ZUPT) gait detection heading constraint

高校网络意识形态安全建设路径研究——基于四川文理学院思想政治教育的视角

在线全文

学校读者我要写书评

暂无评论

四川文理学院学报 2025年第1期35卷 157-160页

作者：闫青赵伟四川文理学院体育学院四川达州635000

互联网的发展对于中国现代化建设的推动作用有目共睹,与此同时,给高校网络意识形态安全带来了较大挑战。基于四川文理学院思想政治教育的视角,以问题为导向,从学生信仰、人才队伍、传播体系和网络综合治理四个方面,探索将党的二十大精... 详细信息

互联网的发展对于中国现代化建设的推动作用有目共睹,与此同时,给高校网络意识形态安全带来了较大挑战。基于四川文理学院思想政治教育的视角,以问题为导向,从学生信仰、人才队伍、传播体系和网络综合治理四个方面,探索将党的二十大精神贯穿高校网络意识形态安全建设的具体路径,理论武装学生,健全思政育人体系;壮大人才队伍,健全理论研究体系;加强媒体建设,健全校园传播体系;优化网络生态,健全网络治理体系。

关键词：二十大精神高校网络意识形态思想政治教育