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圆形压力隧洞限裂配筋设计方法研究

土木工程学报 2011年第10期44卷 143-148页

作者：汪基伟冷飞蒋勇河海大学江苏南京210098

为研究圆形压力隧洞衬砌合理的限裂设计方法,采用钢筋混凝土有限单元法对隧洞衬砌的受力特性进行分析,指出隧洞衬砌具有内力值随衬砌开裂区域增加而减小、配筋取决于裂缝宽度的限制要求而非承载力、规范中的裂缝宽度计算公式不适用等特... 详细信息

为研究圆形压力隧洞衬砌合理的限裂设计方法,采用钢筋混凝土有限单元法对隧洞衬砌的受力特性进行分析,指出隧洞衬砌具有内力值随衬砌开裂区域增加而减小、配筋取决于裂缝宽度的限制要求而非承载力、规范中的裂缝宽度计算公式不适用等特性。通过对厚壁圆筒承载力计算公式的重新推导,指出该方法没有引入裂缝处环向钢筋应变最大值与环向钢筋在整个圆周内平均应变的比值ψ',使得钢筋面积计算值过小。鉴于隧洞衬砌的受力特性及没有合适的ψ'计算方法,建议取消厚壁圆筒公式,而采用钢筋混凝土有限单元法进行隧洞衬砌的配筋计算。对能由有限元计算直接求得裂缝宽度的衬砌,以裂缝宽度限值要求确定钢筋用量与布置;对不能由有限元计算直接求得裂缝宽度的衬砌,以限制钢筋应力来控制裂缝宽度,即以钢筋应力限值要求确定钢筋用量与布置。最后,通过较多的算例给出隧洞衬砌的钢筋应力限值,当保护层厚度为50mm时钢筋应力限值可取120MPa,当保护层厚度为100mm时钢筋应力限值可取100MPa。

关键词：压力隧洞衬砌配筋设计钢筋混凝土有限单元法裂缝宽度限裂设计

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时滞控制理论的研究进展

南京理工大学学报 2005年第S1期29卷 138-142页

作者：何率天达飞鹏尤伟江苏南京210096 东南大学自动控制系东南大学自动控制系江苏南京210096 空军第一航空学院基础部河南信阳464000

时滞是自然界中广泛存在而又不可避免的一种现象。研究时滞现象,对于解决工程中的时延问题,提高控制系统性能,有着理论和实践意义。时滞控制基于内模原理,在控制器中引入时滞项以减少额外的干扰,从而提高控制系统的性能。本文概述了时... 详细信息

时滞是自然界中广泛存在而又不可避免的一种现象。研究时滞现象,对于解决工程中的时延问题,提高控制系统性能,有着理论和实践意义。时滞控制基于内模原理,在控制器中引入时滞项以减少额外的干扰,从而提高控制系统的性能。本文概述了时滞控制理论的最新研究进展,包括:(1)时滞控制系统的数学模型及其分类,系统的鲁棒性与稳定性分析,最优与次优控制等;(2)时滞控制的基本原理与研究现状,时滞控制与其他控制方法的结合情况。最后指出了时滞控制系统需要进一步研究和解决的几个主要问题,并对其未来发展方向做了展望。

关键词：时滞控制稳定性内模原理最优控制

Laser Driver for Optic Fiber Gyro with 4 mA to 200 mA Drive Current

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Journal of Electronic Science and Technology 2013年第3期11卷 277-280页

作者： fei-Xiang Chen Zong-Min Wang Ying Kong Xin-Mang peng he Beijing Microelectronics Technology Institute

Abstract---The stability of the drive current is very important for a laser driver, while it is difficult to maintain the current stable at a high value for the laser driver. On the other hand, the range of the drive current is expected to be as wide as possible to be applied to different kinds of lasers. In this paper, a high current laser driver for the superluminescent light emitting diode （SLED） is presented, which is used in the optic fiber gyro embedded by a 0.35 μm bipolar complementary metal-oxide-semiconductor transistor （BiCMOS） process. The laser driver provides automatic power control and certain value of current determined by the external resister. The system is based on the optic-electric feedback theory and uses the closed-loop control technique to maintain the drive current stable. The system is capable of producing stable current ranges from 4 mA to 200 mA when the value of external resister changes.

关键词： Index Terms---Average power control calibratedreference current high current output laser driver.

Discussion on the Factors Affecting the Stability of Microgrid Based on Distributed Power Supply

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Energy and Power Engineering 2013年第4期5卷 1344-1346页

作者： Ye Xu Zhao-hong Shi Jin-quan Wang peng-fei Hou Power and intelligence teaching and research center PLA University of Science & Technology Nanjing China

This paper summarizes the advantages of application of micro grid, analyzes the structure of microgrid, and discusses the factors, which are important to the stable operation of micro grid. The factors include the tec... 详细信息

关键词： Microgrid Distributed Generation Stability Analysis Energy Storage

Radiation-Assisted Synthesis of Crown Ether-Modified Covalent Organic Frameworks for Lithium Isotope Separation

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CCS Chemistry 2024年第10期6卷 2594-2606页

作者： Shouchao Zhong Yue Wang Jianhui Lan Mingshu Xie Yiqian Wu Jiuqiang Li Fujian Liu Lilong jiang Jing peng Liyong Yuan Maolin Zhai Weiqun Shi Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringBeijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871 National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou350002 Fujian Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049

γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensional crown ether-modified COFs(named[15C5]n%-(TzDa-G-x%)),marking the maiden utilization of COFs in the realm of^(6)Li/^(7)Li isotope *** COFs exhibited swifter adsorption kinetics than alternative *** them,[15C5]_(57%)-(TzDa-G-50%)with its excellent crystallinity,porosity,and stability exhibited the best performance in Li+adsorption and^(6)Li/^(7)Li isotope *** Li+adsorption in acetonitrile achieved a capacity of 3.6 mg·g^(−1)within 30 min and a saturation capacity of 7.3 mg·g^(−1).The single-stage separation factor of^(6)Li/^(7)Li isotopes was 1.014±*** results of dynamic adsorption column experiments showed that the packed column made of[15C5]_(57%)-(TzDa-G-50%)maintained stable performance during four cycles of Li+adsorptionelution,with over 99%Li+removal rate in *** crown ether-modified COF has potential application in^(6)Li/^(7)Li isotope separation,and this radiation-assisted synthesis strategy is expected to become universal in the modification of COFs for diverse applications.

关键词： covalent organic framework gamma radiation modification crown ether ^(6)Li/^(7)Li isotope separation adsorption column

3D Joint inversion of gravity and gravity tensor data

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Global Geology 2018年第1期21卷 55-61页

作者： ZHAO Simin GAO Xiuhe QIAO Zhongkun jiang Dandan ZHOU fei LIN Song College of Geo-Exploration Science and Techonology Jilin UniversityChangchun 130026 Guangzhou Marine Geological Survey Guangzhou 510000China

The processing and interpretation of gravity and gradient data plays an important role in *** cross gradient joint inversion is usually used for achieving structure coupling of multiple geophysical models. In order to realize the coupling of gravity and gravity tensor data,the authors analyzed each *** results show that different types of data contain different direction information,and derived the joint inversion based on cross gradient function and applied it to model data. The theoretical model results show that the cross gradient method can reduce the multi solution and significantly improve the resolution of the *** method was also applied to inverse the gravity tensor data in Vinton salt dome,showing that this method can get higher resolution results than the separate linear inversion,and be closer to the real density from drilling data.

关键词： cross gradient joint inversion gravity data gradient data

Design and performance analysis of RAID based on OSD

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通讯和计算机（中英文版） 2007年第8期4卷 53-58页

作者： jiang Ming-hua HU Ming peng Tao DING Yi-xiang College of Computer Science ＆ Technology Wuhan University of Science ＆ Engineering Wuhan 430073 China

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高压输电线路带电检修机器人作业臂运动优化

工程科学学报 2016年第11期38卷 1643-1651页

作者：江维吴功平樊飞张颉武汉大学动力与机械学院.武汉430072

针对完全依靠人工带电拧紧高压输电线路引流板螺栓作业效率低、劳动强度大、高空和高电压危险的问题,研制了一种双臂和双机械手的引流板螺栓拧紧带电检修机器人.通过各关节的轨迹规划双作业臂及其末端由初始位姿运动到螺栓螺母对准状态... 详细信息

针对完全依靠人工带电拧紧高压输电线路引流板螺栓作业效率低、劳动强度大、高空和高电压危险的问题,研制了一种双臂和双机械手的引流板螺栓拧紧带电检修机器人.通过各关节的轨迹规划双作业臂及其末端由初始位姿运动到螺栓螺母对准状态是机器人顺利完成检修作业的关键.针对现有多项式插值关节轨迹规划依赖于轨迹端点时刻,导致该方法实用性差及关节轨迹运动过程中忽略驱动机构对关节状态制约的问题,提出基于Min-Max时间标准化的改进多项式插值关节轨迹规划方法.基于该方法,以关节运动时间为优化对象,提出满足关节轨迹运动全程约束条件的关节运动时间区间范围的求取方法.通过仿真实验验证了改进算法关节轨迹仅与轨迹端点状态及运动时间有关,而与端点时刻无关,进一步淡化轨迹端点时刻对关节轨迹的影响,提高算法的实用性.通过选取最优关节轨迹运动时间,满足了关节状态全程状态约束要求,从而避免超调的发生,优化了各关节运动轨迹,提高了关节运动的效率.最后通过现场试验进一步验证改进算法的工程实用性.

关键词：高压输电线路机器人作业臂控制运动规划优化

A chromosome-level genome assembly of anesthetic drug–producing Anisodus acutangulus provides insights into its evolution and the biosynthesis of tropane alkaloids

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Plant Communications 2024年第1期5卷 231-244页

作者： Wei Zhou Can Wang Xiaolong Hao fei Chen Qikai Huang Tingyao Liu jiang Xu Shuai Guo Baosheng Liao Zhixiang Liu Yue Feng Yao Wang Pan Liao Jiayu Xue Min Shi Itay Maoz Guoyin Kai Zhejiang Provincial International S&T Cooperation Base for Active Ingredients of Medicinal and Edible Plants and Health Zhejiang Provincial Key TCM Laboratory for Chinese Resource Innovation and TransformationSchool of Pharmaceutical SciencesJinhua AcademyZhejiang Chinese Medical UniversityHangzhouZhejiang 310053China Sanya Nanfan Research Institute from Hainan University Hainan Yazhou Bay Seed LaboratorySanya 572025China Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700China Department of Biology Hong Kong Baptist UniversityKowloon TongHong KongChina College of Horticulture Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjing 210095China Department of Postharvest Science Agricultural Research OrganizationVolcani CenterP.O.Box 15159HaMaccabim Road 68Rishon LeZion 7505101Israel

Tropane alkaloids(TAs),which are anticholinergic agents,are an essential class of natural compounds,and there is a growing demand for TAs with anesthetic,analgesic,and spasmolytic *** acutan-gulus(Solanaceae)is a TA-producing plant that was used as an anesthetic in ancient *** this study,we assembled a high-quality,chromosome-scale genome of *** with a contig N50 of 7.4 Mb.A recent whole-genome duplication occurred in *** after its divergence from other Solanaceae species,which resulted in the duplication of ADC1 and UGT genes involved in TA *** catalytic activities of H6H enzymes were determined for three Solanaceae *** the basis of evolution and co-expressed genes,AaWRKY11 was selected for further analyses,which revealed that its encoded tran-scription factor promotes TA biosynthesis by activating AaH6H1 *** provide useful insights into genome evolution related to TA biosynthesis and have potential implications for genetic manipulation of TA-producing plants.

关键词： Anisodus acutangulus tropane alkaloid biosynthesis hyoscyamine 6 b-hydroxylase AaWRKY11