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Concurrent Two-Scale Topology Optimization of Thermoelastic Structures Using a M-VCUT Level Set Based Model of Microstructures
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作者 Jin Zhou Minjie Shao +1 位作者 Ye Tian Qi Xia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1327-1345,共19页
By analyzing the results of compliance minimization of thermoelastic structures,we observed that microstructures play an important role in this optimization problem.Then,we propose to use a multiple variable cutting(M... By analyzing the results of compliance minimization of thermoelastic structures,we observed that microstructures play an important role in this optimization problem.Then,we propose to use a multiple variable cutting(M-VCUT)level set-based model of microstructures to solve the concurrent two-scale topology optimization of thermoelastic structures.A microstructure is obtained by combining multiple virtual microstructures that are derived respectively from multiple microstructure prototypes,thus giving more diversity of microstructure and more flexibility in design optimization.The effective mechanical properties of microstructures are computed in an off-line phase by using the homogenization method,and then a mapping relationship between the design variables and the effective properties is established,which gives a data-driven model of microstructure.In the online phase,the data-driven model is used in the finite element analysis to improve the computational efficiency.The compliance minimization problem is considered,and the results of numerical examples prove that the proposed method is effective. 展开更多
关键词 Two-scale structure topology optimization multiple variable cutting level set DATA-DRIVEN radial basis function thermoelastic structure
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Study on the Changes of Medical Income Structure in Governmentrun Hospitals of Traditional Chinese Medicine from 2012 to 2021
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作者 Song Yamei 《Asian Journal of Social Pharmacy》 2024年第2期178-190,共13页
Objective To study the changing characteristics and trend of medical income structure in the government-run hospitals of traditional Chinese medicine(TCM),evaluate the effects of relevant reform measures,and to put fo... Objective To study the changing characteristics and trend of medical income structure in the government-run hospitals of traditional Chinese medicine(TCM),evaluate the effects of relevant reform measures,and to put forward corresponding suggestions for further optimizing their income structure.Methods The data related to the average medical income of government-run hospitals of TCM from 2012 to 2021 were sorted out.Then,descriptive analysis method was used to analyze the changes of related indicators.Besides,structural change method was applied to investigate the changes of outpatient income and inpatient income.Results and Conclusion From 2012 to 2021,the growth of medical income in government-run hospitals of TCM tended to be stable,and the proportion of medical service income increased from 22.62%(2012)to 29.38%(2021),but the average annual growth rate was only 0.68%.The main items that caused the change of outpatient income structure were medicine revenue,laboratory tests,diagnosis and treatment,and the cumulative contribution rate was 89.15%.The main items that caused the change of inpatient income structure were medicine revenue,sanitary materials,and auxiliary examinations income,with a cumulative contribution rate of 80.04%.However,the contribution rate of registration,diagnosis,treatment,surgery and nursing income reflecting the value of medical personnel’s technical labor was relatively small.The medical income structure of government-run hospitals of TCM underwent great changes and gradually became reasonable,but the medical service income increased slowly,and not all indicators achieved the expectations.To promote the sustainable development of public hospitals of TCM and enable them to provide high-quality and efficient TCM medical and health services,it is necessary to further improve the relevant policy mechanism. 展开更多
关键词 government-run hospitals of traditional Chinese medicine medical expenses structure optimization sustainable development
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Branch Standards as the Possible Way of Optimizing of Capital Structure of the Concrete Firm 被引量:1
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作者 Milan Hrdy 《Journal of Modern Accounting and Auditing》 2018年第4期165-173,共9页
This article is about the problem of optimizing of the capital structure of the concrete firm and about the possibility to use the passive way of optimizing of this capital structure on the basis of the so-called Bran... This article is about the problem of optimizing of the capital structure of the concrete firm and about the possibility to use the passive way of optimizing of this capital structure on the basis of the so-called Branch standards. Branch standards are defined as some average indebtedness that the firms are trying to follow. There are a lot of theories available, but the final process of optimizing of the capital structure of the concrete firm is very complicated and it is necessary to cope with a lot of application problems. Besides Traditional theory, none of the further theories offer some concrete recommended optimal indebtedness. For that reason, the possibility to optimize the capital structure based on the passive way is represented besides other things by the so-called Branch standards. The aim of this article is to judge if it is possible to identify this average indebtedness in different branches and in different countries. The hypothesis was stated that it is possible only in selected branches in selected countries. The research is realized in the six selected branches: Railroads, Beverages, Steel, Paper Production, Tobacco, and Electrical Equipment in the Czech Republic and in USA. Data for the years 2008-2016 were obtained from the system Albertina Data at the University of Economics in Prague and from the web pages of Prof. Aswath Damodaran in USA. There were identified so-called Branch standards in the Czech Republic for the branches Railroads 45%, Beverages 50%, Tobacco 50%, and Electrical Equipment 40%. There are also identified so-called Branch standards in USA for the branches Railroads 40% and Paper Production 40%-50%. For the branch Paper Production in the Czech Republic and for the branch Beverages in USA were identified ranges of 40%-45% and 40%-50% respectively. The so-called Branch standards were not stated for the branch Steel in both countries and for the branches Tobacco and Electrical Equipment in USA. The values were verified by the data for the year 2016 and the so-called Branch standards were confirmed excluding the branch Steel in both countries and the branches Tobacco and Electrical Equipment in the US. 展开更多
关键词 capital structure optimizing branch standards analysis
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Adjusting and Optimizing Structure of Energy Sources for Power Generation of Fujian Province in the 21st Century
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作者 Chen Chaozhu(Fujian Provincial Electric Power Bureau) 《Electricity》 1997年第3期8-12,共5页
The author puts forward the pattern of optimizing the structure of energy sources for generating power in the early stage of the 21st century in Fujian Province; analyzes imper’tant functions on speeding up nuclear p... The author puts forward the pattern of optimizing the structure of energy sources for generating power in the early stage of the 21st century in Fujian Province; analyzes imper’tant functions on speeding up nuclear power for adjusting the structure of energy sources and heightening economic benefits.and suggests that the first liquefied natural gas combined-cycle power plant will start to build at the end of this century and every effort is made so as to change the recent unreasonable structure of energy source step by step and form the optimized structure of energy sources for generating power, that includes hydropower, thermal power (coal, oil and natural gas), nuclear power, pumpedstorage power, and power from new energy sources. In order to reach the abovementioned significant target, the author discusses the technical and economic measures and the supporting policy to be taken at present and in future. 展开更多
关键词 ENERGY SOURCES GENERATING POWER structure optimization NUCLEAR POWER
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Branch Standards as the Method of Optimizing of Capital Structure
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作者 Milan Hrdy 《Journal of Modern Accounting and Auditing》 2018年第9期512-520,共9页
This article is about the problem of optimizing of the capital structure of the concrete firm and about the possibility to use the passive way of optimizing of this capital structure on the basis of the so-called bran... This article is about the problem of optimizing of the capital structure of the concrete firm and about the possibility to use the passive way of optimizing of this capital structure on the basis of the so-called branch standards.Branch standards are defined as some average indebtedness that the firms are trying to follow.There are a lot of theories available,but the final process of optimizing of the capital structure of the concrete firm is very complicated and it is necessary to cope with a lot of application problems.Besides traditional theory,none of the further theories offer some concrete recommended optimal indebtedness.For that reason,the possibility to optimize the capital structure based on the passive way is represented besides other things by the so-called branch standards.The aim of this article is to judge if it is possible to identify this average indebtedness in different branches and in different countries and continue in the previous researches of the author.The hypothesis was stated that it is possible only in selected branches in selected countries as it was stated also in previous researches of the author.The research is realized in the five selected branches,Pharmacy,Furniture Production,Wood(Forest)Production,Water Supply,and Air Transport in the Czech Republic and in the USA.Data for the years 2008-2016 were obtained from the system Albertina Data at the University of Economics in Prague and from web pages of Prof.Aswath Damodaran in the USA.There were identified so-called branch standards in the Czech Republic for the branch Pharmacy with the indebtedness(45%),Furniture Production with the indebtedness(54%),Water Supply with the indebtedness(30-35%),Wood(Forest)Products with the indebtedness(40%),and Air Transport with the indebtedness(70-75%).There are also identified so-called branch standards in the USA for the branches Pharmacy 34%,Furniture Production 40%and Water Supply 50%–55%.The values were verified by the data for the year 2016 and the so-called branch standards were confirmed excluding the branch Air Transport in the Czech Republic and for the branch Water Supply in the USA.The branches Pharmacy and Furniture Production show small differences. 展开更多
关键词 CAPITAL structure optimizing branch STANDARDS ANALYSIS
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Optimizing forestry industrial structure based on the framework of rationalization,advancement and ecologicalization
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作者 XING Mei-hua HUANG Guang-ti +1 位作者 ZHANG Jun-biao TAN Shi-ming 《Ecological Economy》 2010年第4期395-406,共12页
Under the target of the sustainable development,optimization of forestry industrial structure contains rationalization and advancement of forestry industrial structure in the traditional sense,as well as ecologicaliza... Under the target of the sustainable development,optimization of forestry industrial structure contains rationalization and advancement of forestry industrial structure in the traditional sense,as well as ecologicalization of forestry industrial structure.The connotation of optimization of forestry industrial structure is analyzed at first,and then the paper chooses the typical evaluation indexes from the three sides of rationalization,advancement and ecologicalization to evaluate the current situation of the regional forestry industrial structure.With the aid of the theory of fuzzy mathematics and information entropy,the paper establishes a fuzzy evaluation model which is based on information entropy for optimization of forestry industrial structure,and the evaluation model is applied in the study for the current situation of forestry industrial structure from 2000 to 2006 in Hubei province.The results show that the grade of forestry industrial structure is bad basically during the research,of which the overall level of forestry industrial structure of Hubei province is poor,the degree of utilizing forest resource is lower,and ecological environment in the forest region has been damaged to some extent.On this basis,the author presents the countermeasure to promote the optimization of forestry industrial structure. 展开更多
关键词 Forestry industrial structure OPTIMIZATION Ecologicalization Fuzzy mathematics Entropy method
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Towards the performance limit of catenary meta-optics via field-driven optimization 被引量:1
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作者 Siran Chen Yingli Ha +8 位作者 Fei Zhang Mingbo Pu Hanlin Bao Mingfeng Xu Yinghui Guo Yue Shen Xiaoliang Ma Xiong Li Xiangang Luo 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第5期33-42,共10页
Catenary optics enables metasurfaces with higher efficiency and wider bandwidth,and is highly anticipated in the imaging system,super-resolution lithography,and broadband absorbers.However,the periodic boundary approx... Catenary optics enables metasurfaces with higher efficiency and wider bandwidth,and is highly anticipated in the imaging system,super-resolution lithography,and broadband absorbers.However,the periodic boundary approximation without considering aperiodic electromagnetic crosstalk poses challenges for catenary optical devices to reach their performance limits.Here,perfect control of both local geometric and propagation phases is realized through field-driven optimization,in which the field distribution is calculated under real boundary conditions.Different from other optimization methods requiring a mass of iterations,the proposed design method requires less than ten iterations to get the efficiency close to the optimal value.Based on the library of shape-optimized catenary structures,centimeter-scale devices can be designed in ten seconds,with the performance improved by ~15%.Furthermore,this method has the ability to extend catenary-like continuous structures to arbitrary polarization,including both linear and elliptical polarizations,which is difficult to achieve with traditional design methods.It provides a way for the development of catenary optics and serves as a potent tool for constructing high-performance optical devices. 展开更多
关键词 catenary optics catenary structures field-driven optimization
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Vibration Control of the Rail Grinding Vehicle with Abrasive Belt Based on Structural Optimization and Lightweight Design
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作者 Wengang Fan Shuai Zhang +2 位作者 Zhiwei Wu Yi Liu Jiangnan Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期311-337,共27页
As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performan... As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performance and service life.In order to explore the vibration control method of the rail grinding vehicle with abrasive belt,the vibration response changes in structural optimization and lightweight design are respectively analyzed through transient response and random vibration simulations in this paper.Firstly,the transient response simulation analysis of the rail grinding vehicle with abrasive belt is carried out under operating conditions and non-operating conditions.Secondly,the vibration control of the grinding vehicle is implemented by setting vibration isolation elements,optimizing the structure,and increasing damping.Thirdly,in order to further explore the dynamic characteristics of the rail grinding vehicle,the random vibration simulation analysis of the grinding vehicle is carried out under the condition of the horizontal irregularity of the American AAR6 track.Finally,by replacing the Q235 steel frame material with 7075 aluminum alloy and LA43M magnesium alloy,both vibration control and lightweight design can be achieved simultaneously.The results of transient dynamic response analysis show that the acceleration of most positions in the two working conditions exceeds the standard value in GB/T 17426-1998 standard.By optimizing the structure of the grinding vehicle in three ways,the average vibration acceleration of the whole car is reduced by about 55.1%from 15.6 m/s^(2) to 7.0 m/s^(2).The results of random vibration analysis show that the grinding vehicle with Q235 steel frame does not meet the safety conditions of 3σ.By changing frame material,the maximum vibration stress of the vehicle can be reduced from 240.7 MPa to 160.0 MPa and the weight of the grinding vehicle is reduced by about 21.7%from 1500 kg to 1175 kg.The modal analysis results indicate that the vibration control of the grinding vehicle can be realized by optimizing the structure and replacing the materials with lower stiffness under the premise of ensuring the overall strength.The study provides the basis for the development of lightweight,diversified and efficient rail grinding equipment. 展开更多
关键词 Vibration control Dynamic characteristics Structural optimization Lightweight design Modal analysis
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Optimal Insurance with Background Risk under the Ambiguity and Belief Heterogeneity Structure
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作者 Xiaohan Wang 《Journal of Applied Mathematics and Physics》 2024年第6期2160-2171,共12页
In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal i... In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal insurance contract when maxing the insured’s expected utility of his/her remaining wealth under the smooth ambiguity model and the heterogeneous belief form satisfying the MHR condition. We calculate the insurance premium by using generalized Wang’s premium and also introduce a series of stochastic orders proposed by [1] to describe the relationships among the insurable risk, background risk and ambiguity parameter. We obtain the deductible insurance is the optimal insurance while they meet specific dependence structures. 展开更多
关键词 Optimal Insurance Monotone Hazard Ratio Order Smooth Ambiguity Model Background Risk Belief Heterogeneity structure
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Sintering characteristics of fluxes and their structure optimization 被引量:6
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作者 Gen-sheng Feng Sheng-li Wu +3 位作者 Hong-liang Han Luo-wen Ma Wei-zhong Jiang Xiao-qin Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第3期270-276,共7页
Sintering characteristics of common fluxes and sintering blending ores, such as mineralization capacity, liquid generation capacity, consolidation strength, were examined to master the behavior and effect of fluxes in... Sintering characteristics of common fluxes and sintering blending ores, such as mineralization capacity, liquid generation capacity, consolidation strength, were examined to master the behavior and effect of fluxes in sintering. Based on fundamental studies, sinter pot tests were carried out to obtain the principles of optimizing the sinter flux structure. The results showed that strong mineralization capacity, liquid phase generation capacity, and consolidation strength were obtained as sintering blending ores combined with the calcareous flux, while rela-tively poor sintering characteristics were obtained as sintering blending ores combined with the magnesian flux. High reactive quicklime should be used as much as possible in the sintering mixture. It reached better sintering results while quicklime was used instead of limestone and its appropriate proportion in the sintering mixture was around 4wt%. On the premise of ensuring the MgO content, the dolomite amount should be decreased, and the substitution of quicklime for dolomite caused better sintering results. The granularity of serpentine should be re-fined with a proper size smaller than 2 mm. The application of the divided addition method brought the best sintering performance with 30wt% of quicklime and 70wt% of fuel. 展开更多
关键词 FLUXES SINTERING sintering characteristics structural optimization
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A Practical Study of Knowledge Mapping Empowering the Construction of Engineering Costing Software Application Courses in Undergraduate Colleges and Universities
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作者 Hongmei Wang Ying Lin Xiaolin Gan 《Journal of Contemporary Educational Research》 2024年第9期129-133,共5页
Relying on the talent cultivation program of Chongqing Institute of Engineering,this paper combines the characteristics of the Engineering Costing Software Application course with its current status quo,analyzes the e... Relying on the talent cultivation program of Chongqing Institute of Engineering,this paper combines the characteristics of the Engineering Costing Software Application course with its current status quo,analyzes the existing problems and teaching pain points,and introduces knowledge mapping.The course construction is carried out in terms of the combing of knowledge points,the optimization of the course structure,the innovation of the teaching method,and the evaluation and feedback of the teaching in order to improve the systematicity and structural nature of the teaching content,enhance students’learning experience,and enhance their learning effect.It is conducive to the formation of students’knowledge systems and provides a basis for discussion and reference for improving the quality of teaching and cultivating application-oriented talents who meet the market demand. 展开更多
关键词 Knowledge mapping Curriculum construction structure optimization
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Investigating the Influence of Digital Economy Growth on Industrial Structural Optimization and Upgrading
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作者 Wen Zhang 《Proceedings of Business and Economic Studies》 2024年第2期138-144,共7页
With the rapid development of the social economy,science and technology continue to upgrade and optimize,ushering in the digital era,which provides technical support for industrial innovation and development across al... With the rapid development of the social economy,science and technology continue to upgrade and optimize,ushering in the digital era,which provides technical support for industrial innovation and development across all sectors.At this stage,vigorously developing the digital economy has gradually become the only means to optimize and upgrade the industrial structure.Therefore,local leaders and relevant departments need to enhance the importance of constructing the digital economy,enabling the local industrial structure to be optimized and upgraded under the impetus of the digital economy,ultimately promoting overall economic high-quality development.To this end,this paper,combined with existing research results,first elaborates on the positive impact of the digital economy on the optimization and upgrading of the industrial structure.It then analyzes the challenges hindering the process of industrial structure optimization and upgrading and proposes practical pathways to address them,benefiting relevant stakeholders. 展开更多
关键词 Digital economy Industrial structure Optimization and upgrading Path exploration
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Topology Optimization of Compliant Mechanisms with Geometrical Nonlinearities Using the Ground Structure Approach 被引量:7
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作者 ZHAN Jinqing ZHANG Xianmin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第2期257-263,共7页
The majority of topology optimization of compliant mechanisms uses linear finite element models to find the structure responses.Because the displacements of compliant mechanisms are intrinsically large,the topological... The majority of topology optimization of compliant mechanisms uses linear finite element models to find the structure responses.Because the displacements of compliant mechanisms are intrinsically large,the topological design can not provide quantitatively accurate result.Thus,topological design of these mechanisms considering geometrical nonlinearities is essential.A new methodology for geometrical nonlinear topology optimization of compliant mechanisms under displacement loading is presented.Frame elements are chosen to represent the design domain because they are capable of capturing the bending modes.Geometrically nonlinear structural response is obtained by using the co-rotational total Lagrange finite element formulation,and the equilibrium is solved by using the incremental scheme combined with Newton-Raphson iteration.The multi-objective function is developed by the minimum strain energy and maximum geometric advantage to design the mechanism which meets both stiffness and flexibility requirements, respectively.The adjoint method and the direct differentiation method are applied to obtain the sensitivities of the objective functions. The method of moving asymptotes(MMA) is employed as optimizer.The numerical example is simulated to show that the optimal mechanism based on geometrically nonlinear formulation not only has more flexibility and stiffness than that based on linear formulation,but also has better stress distribution than the one.It is necessary to design compliant mechanisms using geometrically nonlinear topology optimization.Compared with linear formulation,the formulation for geometrically nonlinear topology optimization of compliant mechanisms can give the compliant mechanism that has better mechanical performance.A new method is provided for topological design of large displacement compliant mechanisms. 展开更多
关键词 compliant mechanisms topology optimization geometrical nonlinearities the ground structure approach displacement loading
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Interactive Multi-objective Optimization Design for the Pylon Structure of an Airplane 被引量:4
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作者 An Weigang Li Weiji 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第6期524-528,共5页
The pylon structure of an airplane is very complex, and its high-fidelity analysis is quite time-consuming. If posterior preference optimization algorithm is used to solve this problem, the huge time consumption will ... The pylon structure of an airplane is very complex, and its high-fidelity analysis is quite time-consuming. If posterior preference optimization algorithm is used to solve this problem, the huge time consumption will be unacceptable in engineering practice due to the large amount of evaluation needed for the algorithm. So, a new interactive optimization algorithm-interactive multi-objective particle swarm optimization (IMOPSO) is presented. IMOPSO is efficient, simple and operable. The decision-maker can expediently determine the accurate preference in IMOPSO. IMOPSO is used to perform the pylon structure optimization design of an airplane, and a satisfactory design is achieved after only 12 generations of IMOPSO evolutions. Compared with original design, the maximum displacement of the satisfactory design is reduced, and the mass of the satisfactory design is decreased for 22%. 展开更多
关键词 pylon structure multi-objective optimization algorithm interactive algorithm multi-objective particle swarm optimization neural network
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Separation occurring during the drop weight tear test of thick-walled X80 pipeline steels 被引量:3
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作者 Qing-yun Sha Da-hang Li +1 位作者 Guo-jian Huang Ju Guan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第8期741-747,共7页
A separation phenomenon occurring during the drop weight tear test of commercial thick-walled API (American Petroleum Institute) X80 strip steel was investigated in this work. Microstructural analysis showed that th... A separation phenomenon occurring during the drop weight tear test of commercial thick-walled API (American Petroleum Institute) X80 strip steel was investigated in this work. Microstructural analysis showed that the band structure of bainite elongated along the rolling direction works as the initiation sites of separation. The propagation of separation can be promoted not only by the occurrence of the band structure of martensite/austenite constituent, prior austenite grain boundaries, and elongated bainite, but also by fine acicular ferrite and bainite. Wide separation formed in the former case, while the narrow one appeared in the latter case. acicular ferrite in thick-walled X80 pipeline steel in order Some methods were proposed to obtain fine and homogeneous to minimize the occurrence of separation. 展开更多
关键词 pipeline steel drop weight tear test SEPARATION cracking band structure
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Research on Structural Renewal and Renovation Strategies for Industrial Heritage Projects-A Case Study of the Structural Renovation of the “Dahua 1935” Project
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作者 Jiayi Su 《Journal of World Architecture》 2024年第6期1-7,共7页
The wave of post-industrial evolution has led to the emergence of numerous industrial heritage renovation projects in recent years.The renovation and upgrading of the Dahua 1935 project preserve the memories of the pr... The wave of post-industrial evolution has led to the emergence of numerous industrial heritage renovation projects in recent years.The renovation and upgrading of the Dahua 1935 project preserve the memories of the previous industrial age while incorporating modern materials and technologies,resulting in a design that blends traditional and contemporary elements.This has made Dahua 1935 a new intellectual property(IP)symbol of Xi’an,earning praise from both residents and tourists from other provinces.Additionally,to achieve a unity of art and technology,Dahua 1935 underwent structural reinforcement and optimization to enhance its aesthetic appeal.This paper aims to further explore methods for structural optimization in the renovation of Xi’an’s industrial heritage projects by conducting on-site investigations,data collection,and structural analysis,building upon the structural analysis of Dahua 1935 in Xi’an. 展开更多
关键词 Industrial heritage Urban renewal Structural optimization “Dahua 1935”project Carbon fiber reinforcement method
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The Design of Water-reusing Network with a Hybrid Structure Through Mathematical Programming 被引量:4
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作者 刘永忠 段海涛 冯霄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期1-10,共10页
A new design method for a water-reusing network, with a hybrid structure, to reduce the complexity of the network and to minimize freshwater consumption, is proposed. The unique feature of the methodology proposed .i... A new design method for a water-reusing network, with a hybrid structure, to reduce the complexity of the network and to minimize freshwater consumption, is proposed. The unique feature of the methodology proposed .in this article is to control the complexity of the water network by regulation of the control number in a water-reusing system. It combines the advantages of a conventional water-reusing network and a water-reusing net work with internal water mains. To illustrate the proposed method, a single contaminant system and a multiple contaminant system serve as examples of the problems. 展开更多
关键词 water-reusing network internal water main hybrid structure OPTIMIZATION
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Mechanical Behavior and Shape Optimization of Lining Structure for Subsea Tunnel Excavated in Weathered Slot 被引量:2
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作者 李鹏飞 周晓军 《China Ocean Engineering》 SCIE EI CSCD 2015年第6期875-890,共16页
Subsea tunnel lining structures should be designed to sustain the loads transmitted from surrounding ground and groundwater during excavation. Extremely high pore-water pressure reduces the effective strength of the c... Subsea tunnel lining structures should be designed to sustain the loads transmitted from surrounding ground and groundwater during excavation. Extremely high pore-water pressure reduces the effective strength of the country rock that surrounds a tunnel, thereby lowering the arching effect and stratum stability of the structure. In this paper, the mechanical behavior and shape optimization of the lining structure for the Xiang'an tunnel excavated in weathered slots are examined. Eight cross sections with different geometric parameters are adopted to study the mechanical behavior and shape optimization of the lining structure. The hyperstatic reaction method is used through finite element analysis software ANSYS. The mechanical behavior of the lining structure is evidently affected by the geometric parameters of crosssectional shape. The minimum safety factor of the lining structure elements is set to be the objective function. The efficient tunnel shape to maximize the minimum safety factor is identified. The minimum safety factor increases significantly after optimization. The optimized cross section significantly improves the mechanical characteristics of the lining structure and effectively reduces its deformation. Force analyses of optimization process and program are conducted parametrically so that the method can be applied to the optimization design of other similar structures. The results obtained from this study enhance our understanding of the mechanical behavior of the lining structure for subsea tunnels. These results are also beneficial to the optimal design of lining structures in general. 展开更多
关键词 subsea tunnel lining structure shape optimization safety factor hyperstatic reaction method
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Theoretical Study of Geometric Structures for Ground-state Al_nC(n=2-7) Clusters 被引量:2
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作者 李贵发 鲁世强 彭平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第4期582-590,共9页
With the aid of the molecular orbital DMol3 program,the energetics and electronic structures of several AlnC(n = 2-7) configurations have been searched and calculated by improved minimum energy paths(MEPs) by sett... With the aid of the molecular orbital DMol3 program,the energetics and electronic structures of several AlnC(n = 2-7) configurations have been searched and calculated by improved minimum energy paths(MEPs) by setting "imaging product".A new high symmetry,supervalence isomer of Al5C cluster,i.e.,D5h-Al5C,at the local minimum in the MEPs is detected.Several parameters,such as binding energy,HOMO-LUMO energy gap,vertical electron detachment energy and electron affinity energy,are calculated to characterize and evaluate the stability of three Al5C configurations,i.e.,D5h-Al5C,Cs-Al5C and C1-Al5C.The results show that the D5h-Al5C cluster is the ground state structure instead of Cs-Al5C.Due to the formation of many central σ bonds after polymerizing for D5h-Al5C,the decrease of the energy for HOMO orbit results in more territory for HOMO electrons of dislocation effect,then the energy difference between HOMO and LUMO is increasing to enhance the stability of molecules to produce such supervalence structure of Al5C cluster.The configuration evolution between D5h-Al5C,Cs-Al5C and C1-Al5C and the synthesis preference in the mode of Al5 + C → Al5C reveals that the Cs-Al5C and C1-Al5C con-figurations are permissive to coexist with D5h-Al5C structure in energetics. 展开更多
关键词 density functional theory CI-NEB theory MEP optimization scheme ground state structure supervalence structure
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Concurrent multi-scale design optimization of composite frame structures using the Heaviside penalization of discrete material model 被引量:6
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作者 Jun Yan Zunyi Duan +1 位作者 Erik Lund Guozhong Zhao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第3期430-441,共12页
This paper deals with the concurrent multi-scale optimization design of frame structure composed of glass or carbon fiber reinforced polymer laminates. In the composite frame structure, the fiber winding angle at the ... This paper deals with the concurrent multi-scale optimization design of frame structure composed of glass or carbon fiber reinforced polymer laminates. In the composite frame structure, the fiber winding angle at the micro-material scale and the geometrical parameter of components of the frame in the macro-structural scale are introduced as the independent variables on the two geometrical scales. Considering manufacturing requirements, discrete fiber winding angles are specified for the micro design variable. The improved Heaviside penalization discrete material optimization interpolation scheme has been applied to achieve the discrete optimization design of the fiber winding angle. An optimization model based on the minimum structural compliance and the specified fiber material volume constraint has been established. The sensitivity information about the two geometrical scales design variables are also deduced considering the characteristics of discrete fiber winding angles. The optimization results of the fiber winding angle or the macro structural topology on the two single geometrical scales, together with the concurrent two-scale optimization, is separately studied and compared in the paper. Numerical examples in the paper show that the concurrent multi-scale optimization can further explore the coupling effect between the macro-structure and micro-material of the composite to achieve an ultralight design of the composite frame structure. The novel two geometrical scales optimization model provides a new opportunity for the design of composite structure in aerospace and other industries. 展开更多
关键词 Composite frame structure Multi-scale optimization Topology optimization Fiber winding angle Structural compliance
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