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Structure Design Considerations of a Sub-50nm Self-Aligned Double-Gate MOSFET
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作者 殷华湘 徐秋霞 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第12期1267-1274,共8页
A comprehensive way to design a sub 50nm SADG MOSFET with the ability of being fabricated by improved CMOS technique is described.Under this way,the gate length and thickness of Si island of DG device show many diffe... A comprehensive way to design a sub 50nm SADG MOSFET with the ability of being fabricated by improved CMOS technique is described.Under this way,the gate length and thickness of Si island of DG device show many different scaling limits for various elements.Meanwhile,the spacer insulator shows a kind of width thickness on device drain current and circuit speed.A model about that effect is developed and offers design consideration for future.A new design of channel doping profile,called SCD,is also discussed here in detail.The DG device with SCD can achieve a good balance between the volume inversion operation mode and the control of V th .Finally,a guideline to make a SADG MOSFET is presented. 展开更多
关键词 double gate MOSFET structure design sidewall effect SCD
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Study on the Price Design and Contract Stability of "Company + Farmer" Model with Time Preference under Double Moral Hazards
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作者 高阔 甘筱青 《Agricultural Science & Technology》 CAS 2014年第8期1424-1427,共4页
The double moral hazard of "company + farmer" and the time preference cost of company and farmer was analyzed. According to static game model, it re-vealed that the reason for low compliance rate of "company + fa... The double moral hazard of "company + farmer" and the time preference cost of company and farmer was analyzed. According to static game model, it re-vealed that the reason for low compliance rate of "company + farmer" model was the existence of market risk, namely, the fluctuation of market price, and the stable market price in contracts was actualy a kind of interval, instead of a specific value. Furthermore, the effect of default penalty, market transaction cost and time prefer-ence cost on the stability of contract was studied. The results showed that default penalty, market transaction cost and time preference cost had positive influence on the price interval range of a contract. 展开更多
关键词 "Company+ farmer" double moral hazard Time preference Price design Contract stability
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Layered double hydroxides as electrode materials for flexible energy storage devices 被引量:2
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作者 Qifeng Lin Lili Wang 《Journal of Semiconductors》 EI CAS CSCD 2023年第4期30-45,共16页
To prevent and mitigate environmental degradation,high-performance and cost-effective electrochemical flexible energy storage systems need to be urgently developed.This demand has led to an increase in research on ele... To prevent and mitigate environmental degradation,high-performance and cost-effective electrochemical flexible energy storage systems need to be urgently developed.This demand has led to an increase in research on electrode materials for high-capacity flexible supercapacitors and secondary batteries,which have greatly aided the development of contemporary digital communications and electric vehicles.The use of layered double hydroxides(LDHs)as electrode materials has shown productive results over the last decade,owing to their easy production,versatile composition,low cost,and excellent physicochemical features.This review highlights the distinctive 2D sheet-like structures and electrochemical characteristics of LDH materials,as well as current developments in their fabrication strategies for expanding the application scope of LDHs as electrode materials for flexible supercapacitors and alkali metal(Li,Na,K)ion batteries. 展开更多
关键词 layered double hydroxide flexible energy storage devices structural designs electrochemical performances
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Conceptual Design Optimization of Fighter Trainer Aircraft with Double-delta Wing Configuration 被引量:1
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作者 黄俊 M.I.Mostafa 武哲 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2003年第2期80-85,共6页
Compared with a delta wing aircraft, the double delta wing configuration has better aerodynamic performance at high angles of attack. An operational analysis was introduced as a method for evaluating training effecti... Compared with a delta wing aircraft, the double delta wing configuration has better aerodynamic performance at high angles of attack. An operational analysis was introduced as a method for evaluating training effectiveness of trainer aircraft. Approaches to the engineering estimation of aerodynamic characteristics for aircraft with a double delta wing configuration were studied, and the procedures for determining aircraft performance indices formulated. Taking training effectiveness as the objective function and geometric parameters of the wing platform as design variables, through a numerical multivariate optimization arithmetic, the conceptual design optimization for a certain fighter trainer aircraft with double delta wing configuration was carried out under the constraints of tactical and technical requirements and interrelated geometry. Agreement of a calculation example with engineering practice indicates that the optimal design has higher training effectiveness than the baseline design, and in addition, improves the structural force bearing conditions. 展开更多
关键词 TRAINER conceptual design OPTIMIZATION training effectiveness double delta wing
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Rational architecture design of yolk/double-shells Si-based anode material with double buffering carbon layers for high performance lithium-ion battery 被引量:1
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作者 Zhenyu Wu Jing Luo +3 位作者 Jiao Peng Hong Liu Baobao Chang Xianyou Wang 《Green Energy & Environment》 SCIE CSCD 2021年第4期517-527,共11页
Among the many strategies to fabricate the silicon/carbon composite,yolk/double-shells structure can be regarded as an effective strategy to overcome the intrinsic defects of Si-based anode materials for Li-ion batter... Among the many strategies to fabricate the silicon/carbon composite,yolk/double-shells structure can be regarded as an effective strategy to overcome the intrinsic defects of Si-based anode materials for Li-ion batteries(LIBs).Hereon,a facile and inexpensive technology to prepare silicon/carbon composite with yolk/double-shells structure is proposed,in which the double buffering carbon shells are fabricated.The silicon/carbon nanoparticles with core-shell structure are encapsulated by SiO_(2)and external carbon layer,and it shows the yolk/double-shells structure via etching the SiO_(2)sacrificial layer.The multiply shells structure not only significantly improves the electrical conductivity of composite,but also effectively prevents the exposure of Si particles from the electrolyte composition.Meanwhile,the yolk/double-shells structure can provide enough space to accommodate the volume change of the electrode during charge/discharge process and avoid the pulverization of Si particles.Moreover,the as-prepared YDS-Si/C shows excellent performance as anode of LIBs,the reversible capacity is as high as 1066 mA h g^(-1) at the current density of 0.5 A g^(-1) after 200 cycles.At the same time,the YDS-Si/C has high capacity retention and good cyclic stability.Therefore,the unique architecture design of yolk/double-shells for Si/C composite provides an instructive exploration for the development of next generation anode materials of LIBs with high electrochemical performances and structural stability. 展开更多
关键词 Silicon/carbon composite Structure design Yolk/double-shells double buffering carbon layers Li-ion batteries
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Teaching Reform and Research on Art Design Majors in Higher Vocational Colleges under the Background of “Double High Plan” 被引量:1
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作者 Xin Zhang 《Journal of Contemporary Educational Research》 2021年第1期20-23,共4页
Training talents for the society is the responsibility of colleges and universities.The society needs applied and innovative art design majors.In order to cultivate talents needed by society and keep up with the devel... Training talents for the society is the responsibility of colleges and universities.The society needs applied and innovative art design majors.In order to cultivate talents needed by society and keep up with the development plan of the Ministry of Education,higher vocational colleges need to reform.This paper adopts the method of theoretical analysis to elaborate from the four aspects of focusing equally on science and education,promote learning by competition;integrating industry and education,nurturing talents together;keeping the mission in mind while serving students;and finding the right positioning,giving full play to the advantages. 展开更多
关键词 "double High Plan" Higher Vocational Colleges Art design Major Teaching Reform
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双十字路口交通灯控制Stateflow和App Designer仿真
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作者 张悦 周泽震 +1 位作者 颜秀铭 杨燕 《电气电子教学学报》 2024年第3期218-224,共7页
为培养学生能够独立从事自动化相关领域的工程设计、应用研究,解决自动化领域复杂工程实施过程中遇到的关键技术问题,以双十字路口交通灯为研究对象,为计算机辅助建模与仿真类课程设计了一个综合性教学案例。教学案例主要内容为双十字路... 为培养学生能够独立从事自动化相关领域的工程设计、应用研究,解决自动化领域复杂工程实施过程中遇到的关键技术问题,以双十字路口交通灯为研究对象,为计算机辅助建模与仿真类课程设计了一个综合性教学案例。教学案例主要内容为双十字路口Simulink/Stateflow建模与基于Matlab App Designer的交通灯控制可视化仿真。通过此教学案例的实施,明显提高了学生对Matlab的综合应用和工程设计能力,并为后续课程“单片机原理及应用”和“电气控制和PLC”作铺垫。 展开更多
关键词 双十字路口 交通灯控制 SIMULINK STATEFLOW App designer
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Research on Innovation of Modern Apprenticeship Talent Training Model for Art and Design Majors in Higher Vocational Education under the Background of "Double High"
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作者 Lu Zhang 《Journal of Contemporary Educational Research》 2021年第1期31-34,共4页
In order to cultivate more excellent talents in art and design majors following the requirements of the"13th Five-Year Plan"national education development,this paper analyzes in-depth on the current status o... In order to cultivate more excellent talents in art and design majors following the requirements of the"13th Five-Year Plan"national education development,this paper analyzes in-depth on the current status of higher vocational education in art design profession under the background of the"Double High"plan and the challenges faced,and proposes the building of school-enterprise"Double Subject"education system and the establishment of a"diversified"evaluation system.Deepening the integration of industry and education,schools and enterprises jointly explore modern apprenticeship talent training models for innovative art and design majors,and provide a strong guarantee for the implementation of the"Double High"plan modern apprenticeship talent training model. 展开更多
关键词 "double High"Plan Art design Profession Modern Apprenticeship System Talent Training
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Design and motion control analysis of double helix wall climbing robot
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作者 Jinzhan WANG Minglu CHI +6 位作者 Yue MA Qinchao REN Mengqing HUANG Yibo CHEN Ruihua REN Jinyu WANG Si LIU 《Mechanical Engineering Science》 2022年第1期27-34,共8页
For the detection environment of complex walls such as high-rise buildings,a double helix wall climbing robot(DHWCR)with strong adsorption force and good stability is designed and developed,which uses symmetrical prop... For the detection environment of complex walls such as high-rise buildings,a double helix wall climbing robot(DHWCR)with strong adsorption force and good stability is designed and developed,which uses symmetrical propellers to provide adsorption force.The symmetrical driving structure can provide smooth thrust for the DHWCR,so that the robot can be absorbed to the wall surface with different roughness.A left and right control frame with multiple degrees of freedom is designed,which can adjust the fixed position of the brushless propeller motor in the front and back directions,realize the continuous adjustable thrust direction of the robot,and improve the flexibility of the robot movement.Using the front wheel steering mechanism with universal joint,the steering control of the DHWCR is realized by differential control.In the vertical to ground transition,the front and rear brushless motors can provide the pull up and oblique thrust,so that the DHWCR can smoothly transition to the vertical wall.The motion performance and adaptability of the DHWCR in the horizontal ground and vertical wall environment are tested.The results show that the DHWCR can switch motion between the horizontal ground and vertical wall,and can stably adsorb on the vertical wall with flexible attitude control.The DHWCR can move at a fast speed.The speed on the horizontal ground is higher than that on the vertical wall,which verifies the feasibility and reliability of the DHWCR moving stably on the vertical wall. 展开更多
关键词 double helix Wall climbing robot Reverse thrust adsorption Structural design Motion control
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Optimized Simulation Design of Double Glass Curtain Wall Shading System in Hot Summer and Cold Winter Zone
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作者 Li-Sha He Lin-Sen Mu Jie Shen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期66-71,共6页
The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wal... The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wall are often exposed. Aiming at office buildings in hot Summer and cold Winter zone, taking the optimization of thermal comfort of double glass curtain wall in the summer and the reduetion of building energy consumption throughout the year as the breakthrough point, using the method of energy simulation analysis, through changing the size of internal shading component in the simulated room, this paper analyzes and summarizes the variation law of its energy consumption value, to explore the relatively reasonable design plan of shading systems of the building with glass curtain wall. 展开更多
关键词 rdouble glass curtain wall building energy efficiency optimized simulation design
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Double设计在对称化L_2-偏差下的均匀性 被引量:2
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作者 雷轶菊 覃红 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第3期369-372,共4页
二水平部分因子设计在工农业生产、科学实验等领域得到广泛应用,因此有关二水平部分因子设计的研究一直是热点问题.最近,一种称为doubling的方法被用来构造二水平部分因子设计,特别是在构造分辨度为Ⅳ的设计时,这种方法是非常简单但很... 二水平部分因子设计在工农业生产、科学实验等领域得到广泛应用,因此有关二水平部分因子设计的研究一直是热点问题.最近,一种称为doubling的方法被用来构造二水平部分因子设计,特别是在构造分辨度为Ⅳ的设计时,这种方法是非常简单但很实用的方法,本文从均匀性的角度来研究double设计,进一步讨论doubling方法的实用性,利用对称化L_2-偏差作为均匀性的测度,发现double设计D(X)的均匀性与初始设计X的均匀性有着密切的联系,给出了double设计在对称化L_2-偏差下的下界. 展开更多
关键词 double设计 对称化L2-偏差 均匀性 均匀设计
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Q和Q_B准则在Double设计中的应用
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作者 张裕 鲁倩 覃红 《应用数学》 CSCD 北大核心 2008年第S1期43-47,共5页
一阶回归模型通常用来从众多因子当中筛选出效应显著的因子,而Q和QB准则能够比较简单地从众多合格的拟合子模型中找出最优设计.因此本文主要探讨了极大模型为一阶回归模型时,初始设计d分别与Double设计d dd-d,完全反转设计d-d,设计dd11-... 一阶回归模型通常用来从众多因子当中筛选出效应显著的因子,而Q和QB准则能够比较简单地从众多合格的拟合子模型中找出最优设计.因此本文主要探讨了极大模型为一阶回归模型时,初始设计d分别与Double设计d dd-d,完全反转设计d-d,设计dd11-dd22之间的关系,以及它们在Q和QB准则下的最优性关系. 展开更多
关键词 double设计 Q和QB准则 HADAMARD矩阵 极大模型
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Double设计的几个结果
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作者 欧祖军 《长春大学学报》 2010年第12期60-62,共3页
讨论了Double设计在对称化L2-偏差下的均匀性,给出了Double设计为均匀设计的充要条件,同时得到了Double设计的对称化L2-偏差的下界,来评价Double设计的均匀性,最后通过一个例子来验证理论结果。
关键词 对称化L2-偏差 double设计 下界 均匀性
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Double设计在对称化L_2-偏差下两个下界的比较
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作者 雷轶菊 《新乡学院学报》 2015年第3期1-3,共3页
从列平衡的角度出发,将设计的中心化L2-偏差、对称化L2-偏差、可卷L2-偏差分别用二次型和均衡模式表示,可分别得到两个下界,它们都适合用来评价正交设计的均匀性。以double设计的对称化L2-偏差为例,证明了这两种方法算出的下界是相等的。
关键词 double设计 对称化L2-偏差 下界
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Double设计在对称化L_2-偏差下的广义字长型
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作者 雷轶菊 《江苏教育学院学报(自然科学版)》 2012年第4期14-15,92,共2页
在工农业生产、科学实验等领域都广泛应用到二水平部分因子设计.最近,在构造二水平部分因子设计时一种称为doubling的方法被使用.特别是在构造分辨度为IV的设计时,doubling是非常简单但很实用的方法.本文利用对称化L2-偏差作为均匀性的... 在工农业生产、科学实验等领域都广泛应用到二水平部分因子设计.最近,在构造二水平部分因子设计时一种称为doubling的方法被使用.特别是在构造分辨度为IV的设计时,doubling是非常简单但很实用的方法.本文利用对称化L2-偏差作为均匀性的测度,得到了double设计D(X)的对称化L2-偏差值与初始设计X的广义字长型之间的关系.利用上述关系,我们断定对于具有广义较小低阶混杂的初始设计X,其对应的double设计D(X)也应该具有较小的对称化L2-偏差值,也就是说,D(X)应该具有较好的均匀性. 展开更多
关键词 double设计 对称化L2-偏差 均匀性 广义字长型
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Advances in preparation methods and mechanism analysis of layered double hydroxide for lithium-ion batteries and lithium-sulfur batteries 被引量:1
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作者 Wen Yu Nanping Deng +3 位作者 Kewei Cheng Jing Yan Bowen Cheng Weimin Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期472-499,共28页
Lithium-ion(Li-ion) battery and lithium-sulfur(Li-S) battery have attracted significant attention as promising components for large-scale energy storage because of high theoretical capacity of Li,excellent energy dens... Lithium-ion(Li-ion) battery and lithium-sulfur(Li-S) battery have attracted significant attention as promising components for large-scale energy storage because of high theoretical capacity of Li,excellent energy density or environmental friendness for two kinds of batteries.However,there still exist some respective obstacles for commercial applications,such as limited theoretical capacity,high cost and low conductivity of Li-ion cells or shuttle effect of lithium polysulfides of Li-S cells.As typical twodimensional materials,layered double hydroxides(LDHs) exhibit excellent potential in the field of energy storage due to facile tunability of composition,structure and morphology as well as convenient composite and strong catalytic properties.Consequently,various LDHs toward novel separators or interlayers,cathodes,anodes,and interesting catalytic templates are researched to resolve these challenges.In this review,the recent progress for LDHs applied in Li-ion batteries and Li-S batteries including the synthesis methods,designs and applications is presented and reviewed.Meanwhile,the existing challenges and future perspectives associated with material designs and practical applications of LDHs for these two classes of cells are discussed.WeWe hope that the review can attract more attention and inspire more profound researches toward the LDH-based electrochemical materials for energy storage. 展开更多
关键词 Layered double hydroxide Synthesis methods Structural designs Lithium-ion battery Lithium-sulfur battery Electrochemical performances
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Integrated Nanostructural Electrodes Based on Layered Double Hydroxides 被引量:6
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作者 Wenfu Xie Yuke Song +2 位作者 Shijin Li Mingfei Shao Min Wei 《Energy & Environmental Materials》 2019年第3期158-171,共14页
Layered double hydroxides(LDHs), as a class of typical two-dimensional materials, have sparked increasing interest in the field of energy storage and conversion. In the last few years, the research about LDHs as elect... Layered double hydroxides(LDHs), as a class of typical two-dimensional materials, have sparked increasing interest in the field of energy storage and conversion. In the last few years, the research about LDHs as electrode active materials has seen much progress in terms of structure designing, material synthesis, properties tailoring, and applications. In this review, we focus on the integrated nanostructural electrodes(INEs) construction using LDH materials, including pristine LDH-INEs, hybrid LDH-INEs, and LDH derivativeINEs, as well as the performance advantages and applications of LDH-INEs.Moreover, in the final section, the insights about challenges and prospective in this promising research field were concluded, especially in regulation of intrinsic activity and uncovering of structure–activity relationship, which would push forward the development of this fast-growing field. 展开更多
关键词 electrochemical redox reaction electrode design energy storage and conversion Integrated nanostructural electrodes layered double hydroxides
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Design of an Ultrafast Frequency Doubling Photonic Device
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作者 黄金哲 苏林 +2 位作者 浦绍质 孙上傲 张留洋 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期67-70,共4页
Ultrashort pulses complicate the frequency conversion in a nonlinear crystal, where group velocity mismatch becomes the main obstacle due to dispersion. We present a design for group velocity compensated second harmon... Ultrashort pulses complicate the frequency conversion in a nonlinear crystal, where group velocity mismatch becomes the main obstacle due to dispersion. We present a design for group velocity compensated second harmonic generation in a modulated nonlinear structure, embedded in a liquid crystal box. In this structure, nonlinear crystals act as sources of signal and liquid crystals compensate for group velocity mismatch originating from nonlinear crystals. There are the advantages of the flexible, controllable birefringence of liquid crystals. Meanwhile, a method calculating the parameters of this type of structure is presented. To make it clear, an example is provided. Furthermore, the structure can also be shaped as a waveguide to support integration into other optical devices, applicable to all-optical processing systems. 展开更多
关键词 of on BE is it design of an Ultrafast Frequency doubling Photonic Device in for BBO
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The Layout and Simulation of Logarithmic Spiral Double Curved Arch Dam Transverse Joints
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作者 DU Ting-na DU Qi-lu HUI Yuan 《Computer Aided Drafting,Design and Manufacturing》 2011年第1期8-12,共5页
Because of its good condition with mechanics, logarithmic spiral double curve arch bam has been widely used in the practical engineering. The introduction of a new method in how to divide transverse joint in arch dam ... Because of its good condition with mechanics, logarithmic spiral double curve arch bam has been widely used in the practical engineering. The introduction of a new method in how to divide transverse joint in arch dam will be given and the further research of its calculation has been done. The C++ is used in electronic procedure and the 3D simulation has been finished with AutoCAD, which will provide the object model for computer simulation of the arch dam and the division of finite element mesh. Meanwhile, this method in dividing the transverse joint in arch dam also can be taken as the calculated basis for the design and calculation of arch dam, construction lofting and the calculation of the work amount. 展开更多
关键词 the application of computer logarithmic spiral double curved arch dam transverse joints arched girder 3D modeling the design of C++ procedure
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Stress and thickness calculation of a bolted flat cover with double metal sealing rings
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作者 Xiao-Yan Wang Shi-Feng Zhu +1 位作者 Xiao Wang Xiao-Chun Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第8期210-217,共8页
The design of a bolted flat cover is extremely important for the structural integrity of pressure vessels.The present design codes provide the thickness calculation equations for a bolted flat cover with single metal ... The design of a bolted flat cover is extremely important for the structural integrity of pressure vessels.The present design codes provide the thickness calculation equations for a bolted flat cover with single metal gasket.However,the rules for a bolted flat cover with double metal sealing rings are not developed to date.In the study,a new thickness calculation equation for the bolted flat cover with double metal sealing rings is proposed.First,the theoretical stress solution for bolted flat cover with the double metal sealing rings is obtained,based on the theory of simply supported circular plate and then verified using the results from finite element analyses.The results indicate that the influence of double metal sealing ring on the stress of the flat cover is more serious compared to single metal gasket.Second,a more accurate and reasonable equation is proposed to calculate the thickness of bolted flat cover with double metal sealing rings based on the derived theoretical equations of maximum stress.Finally,the influence of linear load and the spacing between rings on the thickness are discussed.Subsequently,a few suggestions are provided to design low-pressure or atmosphere pressure vessels.The study provides a theoretical foundation to develop design codes of pressure vessels in nuclear reactors. 展开更多
关键词 厚度计算 扁平 金属 封面 戒指 应力和 计算方程 压力解
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