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HB-Continuous Mappings in L-Topological Space
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作者 Najah A. AlSaedi 《Advances in Pure Mathematics》 2024年第5期333-353,共21页
In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new... In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new definition of fuzzy H-continuous [1] which is called HB-continuity on the basis of the notion of H-bounded L-subsets in L-topological space. Then we give characterizations and properties by making use of HB-converges theory of L-molecular nets and L-ideals. 展开更多
关键词 L-Topological Space HB-Closed Set H-Bounded Set HB-continuous mappings HB-Convergence L-Molecular Nets L-Ideals
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A Note on Topological Entropy of Continuous Self-Maps
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作者 Zabidin Salleh 《Journal of Mathematics and System Science》 2015年第3期93-99,共7页
Topological entropy can be an indicator of complicated behavior in dynamical systems. It is first introduce by Adler, Konheim and McAndrew by using open covers in 1965. After that it is still an active research by man... Topological entropy can be an indicator of complicated behavior in dynamical systems. It is first introduce by Adler, Konheim and McAndrew by using open covers in 1965. After that it is still an active research by many researchers to produce more properties and applications up to nowadays. The purpose of this paper is to review and explain most important concepts and results of topological entropies of continuous self-maps for dynamical systems on compact and non-compact topological and metric spaces. We give proofs for some of its elementary properties of the topological entropy. Slight modification on Adler's topological entropy is also presented. 展开更多
关键词 Dynamical system topological entropy continuous maps compact space metric space.
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Continuous Selections and Fixed Points forφ-maps with Their Applications to Section Problems
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作者 PIAO YONG-JIE JIN HAI-LAN PIAO GUANG-RI 《Communications in Mathematical Research》 CSCD 2012年第3期225-234,共10页
The concept of finitely continuous topological space is introduced and the basic properties of the space are given. Several continuous selection theorems and fixed point theorems for Ф-maps are established, and as ap... The concept of finitely continuous topological space is introduced and the basic properties of the space are given. Several continuous selection theorems and fixed point theorems for Ф-maps are established, and as applications of the above fixed point theorems, some section problems are discussed. The results generalize and improve many corresponding conclusions. 展开更多
关键词 FC-SPACE FC-subset Ф-map continuous selection fixed point section problem
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Characteristics of glucose change in diabetes mellitus generalized through continuous wavelet transform processing:A preliminary study
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作者 Yoichi Nakamura Shinya Furukawa 《World Journal of Diabetes》 SCIE 2023年第10期1562-1572,共11页
BACKGROUND The continuous glucose monitoring(CGM)system has become a popular evaluation tool for glucose fluctuation,providing a detailed description of glucose change patterns.We hypothesized that glucose fluctuation... BACKGROUND The continuous glucose monitoring(CGM)system has become a popular evaluation tool for glucose fluctuation,providing a detailed description of glucose change patterns.We hypothesized that glucose fluctuations may contain specific information on differences in glucose change between type 1 diabetes mellitus(T1DM)and type 2 diabetes mellitus(T2DM),despite similarities in change patterns,because of different etiologies.Unlike Fourier transform,continuous wavelet transform(CWT)is able to simultaneously analyze the time and frequency domains of oscillating data.AIM To investigate whether CWT can detect glucose fluctuations in T1DM.METHODS The 60-d and 296-d glucose fluctuation data of patients with T1DM(n=5)and T2DM(n=25)were evaluated respectively.Glucose data obtained every 15 min for 356 d were analyzed.Data were assessed by CWT with Morlet form(n=7)as the mother wavelet.This methodology was employed to search for limited frequency glucose fluctuation in the daily glucose change.The frequency and enclosed area(0.02625 scalogram value)of 18 emerged signals were compared.The specificity for T1DM was evaluated through multiple regression analysis using items that demonstrated significant differences between them as explanatory variables.RESULTS The high frequency at midnight(median:75 Hz,cycle time:19 min)and middle frequency at noon(median:45.5 Hz,cycle time:32 min)were higher in T1DM vs T2DM(median:73 and 44 Hz;P=0.006 and 0.005,respectively).The area of the>100 Hz zone at midnight to forenoon was more frequent and larger in T1DM vs T2DM.In a day,the lower frequency zone(15-35 Hz)was more frequent and the area was larger in T2DM than in T1DM.The threedimensional scatter diagrams,which consist of the time of day,frequency,and area of each signal after CWT,revealed that high frequency signals belonging to T1DM at midnight had a loose distribution of wave cycles that were 17-24 min.Multivariate analysis revealed that the high frequency signal at midnight could characterize T1DM(odds ratio:1.33,95%confidence interval:1.08-1.62;P=0.006).CONCLUSION CWT might be a novel tool for differentiate glucose fluctuation of each type of diabetes mellitus using CGM data. 展开更多
关键词 continuous glucose monitoring PATHOPHYSIOLOGY Fourier Pseudo-frequency Contour map Scalogram matrix
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Fatigue Topology Optimization Design Based on Distortion Energy Theory and Independent Continuous Mapping Method 被引量:2
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作者 Hongling Ye Zonghan Li +2 位作者 Nan Wei Pengfei Su Yunkang Sui 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第7期297-314,共18页
Fatigue failure is a common failure mode under the action of cyclic loads in engineering applications,which often occurs with no obvious signal.The maximum structural stress is far below the allowable stress when the ... Fatigue failure is a common failure mode under the action of cyclic loads in engineering applications,which often occurs with no obvious signal.The maximum structural stress is far below the allowable stress when the structures are damaged.Aiming at the lightweight structure,fatigue topology optimization design is investigated to avoid the occurrence of fatigue failure in the structural conceptual design beforehand.Firstly,the fatigue life is expressed by topology variables and the fatigue life filter function.The continuum fatigue optimization model is established with the independent continuous mapping(ICM)method.Secondly,fatigue life constraints are transformed to distortion energy constraints explicitly by taking advantage of the distortion energy theory.Thirdly,the optimization formulation is solved by the dual sequence quadratic programming(DSQP).And the design scheme of lightweight structure considering the fatigue characteristics is obtained.Finally,numerical examples illustrate the practicality and effectiveness of the fatigue optimization method.This method further expands the theoretical application of the ICM method and provides a novel approach for the fatigue optimization problem. 展开更多
关键词 Fatigue optimization distortion energy theory S-N curve independent continuous mapping method
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CONTINUOUS SELECTION THEOREMS FOR FAN-BROWDER MAPPINGS IN TOPOLOGICAL SPACES AND THEIR APPLICATIONS
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作者 杨明歌 邓磊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第4期493-500,共8页
The concept of Fan-Browder mappings was first introduced in topological spaces without any convex structure. Then a new continuous selection theorem was obtained for the Fan-Browder mapping with range in a topological... The concept of Fan-Browder mappings was first introduced in topological spaces without any convex structure. Then a new continuous selection theorem was obtained for the Fan-Browder mapping with range in a topological space without any convex structure and noncompact domain. As applications, some fixed point theorems, coincidence theorems and a nonempty intersection theorem were given. Both the new concepts and results unify and extend many known results in recent literature. 展开更多
关键词 Fan-Browder mapping continuous selection fixed point coincidence point
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Block and parallel modelling of broad domain nonlinear continuous mapping based on NN
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作者 Yang Guowei Tu Xuyan Wang Shoujue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期586-592,共7页
The necessity of the use of the block and parallel modeling of the nonlinear continuous mappings with NN is firstly expounded quantitatively. Then, a practical approach for the block and parallel modeling of the nonli... The necessity of the use of the block and parallel modeling of the nonlinear continuous mappings with NN is firstly expounded quantitatively. Then, a practical approach for the block and parallel modeling of the nonlinear continuous mappings with NN is proposed. Finally, an example indicating that the method raised in this paper can be realized by suitable existed software is given. The results of the experiment of the model discussed on the 3-D Mexican straw hat indicate that the block and parallel modeling based on NN is more precise and faster in computation than the direct ones and it is obviously a concrete example and the development of the large-scale general model established by Tu Xuyan. 展开更多
关键词 model nonlinear continuous mapping neural network parallel modelling.
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On Some Properties of Neutrosophic Semi Continuous and Almost Continuous Mapping
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作者 Bhimraj Basumatary Nijwm Wary +1 位作者 Jeevan Krishna Khaklary Usha Rani Basumatary 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第2期1017-1031,共15页
The neutrality’s origin,character,and extent are studied in the Neutrosophic set.The neutrosophic set is an essential issue to research since it opens the door to a wide range of scientific and technological applicat... The neutrality’s origin,character,and extent are studied in the Neutrosophic set.The neutrosophic set is an essential issue to research since it opens the door to a wide range of scientific and technological applications.The neutrosophic set can find its spot to research because the universe is filled with indeterminacy.Neutrosophic set is currently being developed to express uncertain,imprecise,partial,and inconsistent data.Truth membership function,indeterminacymembership function,and falsitymembership function are used to express a neutrosophic set in order to address uncertainty.The neutrosophic set producesmore rational conclusions in a variety of practical problems.The neutrosophic set displays inconsistencies in data and can solve real-world problems.We are directed to do our work in semi-continuous and almost continuous mapping on the basis of the neutrosophic set by observing these.Since we are going to study the properties of semi continuous and almost continuous mapping,we present the meaning of N-semi-open set,N-semi-closed set,N-regularly open set,N-regularly closed set,N-continuous mapping,N-open mapping,N-closed mapping,Nsemi-continuous mapping,N-semi-open mapping,N-semi-closed mapping.Additionally,we attempt to demonstrate a portion of their properties and furthermore referred to some examples. 展开更多
关键词 N-regularly open set N-regularly closed set N-semi-continuous mapping N-almost continuous mapping
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Sub-Differential Characterizations of Non-Smooth Lower Semi-Continuous Pseudo-Convex Functions on Real Banach Spaces
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作者 Akachukwu Offia Ugochukwu Osisiogu +4 位作者 Theresa Efor Friday Oyakhire Monday Ekhator Friday Nkume Sunday Aloke 《Open Journal of Optimization》 2023年第3期99-108,共10页
In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Su... In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Sub-differential. We extend the results on the characterizations of non-smooth convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the monotonicity of its sub-differentials to the lower semi-continuous pseudo-convex functions on real Banach spaces. 展开更多
关键词 Real Banach Spaces Pseudo-Convex Functions Pseudo-Monotone maps Sub-Differentials Lower Semi-continuous Functions and Approximate Mean Value Inequality
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Logistic映射下N-continuous OFDM加密方案 被引量:2
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作者 曹礼梅 周杰 +1 位作者 罗宏 邵根富 《安徽大学学报(自然科学版)》 CAS 北大核心 2018年第6期71-77,共7页
针对信号传输安全问题,提出利用混沌随机性和初值敏感性相结合的数据传输加密方案.该方案首先利用混沌产生随机混沌序列,然后用该序列改变传输数据的相位以及系统子载波的映射规则,最后利用密钥恢复信号.仿真结果表明该方案能有效对系... 针对信号传输安全问题,提出利用混沌随机性和初值敏感性相结合的数据传输加密方案.该方案首先利用混沌产生随机混沌序列,然后用该序列改变传输数据的相位以及系统子载波的映射规则,最后利用密钥恢复信号.仿真结果表明该方案能有效对系统进行数据加密,加密效果良好,在保证高频谱利用率和较强分配灵活性的同时,能增强旁瓣抑制效果.因此,该方案能确保数据传输安全. 展开更多
关键词 N阶连续正交频分复用 LOGISTIC混沌映射 传输安全 混沌
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ON THE EXISTENCE OF ZERO POINTS OF A CONTINUOUS FUNCTION 被引量:7
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作者 J.M. SorianoDepartamento de Andlisis Matematico, Facultad de Matemdticas, Universidad de Sevilla, Aptdo. 1160, Sevilla 41080, Spain 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期171-177,共7页
A sufficient condition is given to assert that a continuous mapping between Rm and Rn has a zero. The constructive proof of the result is based upon continuation methods and supplies the existence of a path leading to... A sufficient condition is given to assert that a continuous mapping between Rm and Rn has a zero. The constructive proof of the result is based upon continuation methods and supplies the existence of a path leading to the zero point. 展开更多
关键词 Zero point continuation methods Banach fixed point theorem HOMOTOPY topological direct sum ISOMORPHISM k-contractive mapping
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ALGORITHMS FOR A SYSTEM OF GENERALIZED MIXED EQUILIBRIUM PROBLEMS AND A COUNTABLE FAMILY OF SOME NONLINEAR MULTI-VALUED NONEXPANSIVE-TYPE MAPS
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作者 Ogonnaya Michael ROMANUS Ukamaka Victoria NNYABA Monday Ogudu NNAKWE 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1805-1820,共16页
In this paper, relaxed iterative algorithms of Krasnoselskii-type and Halpern-type that approximate a solution of a system of a generalized mixed equilibrium problem anda common fixed point of a countable family of to... In this paper, relaxed iterative algorithms of Krasnoselskii-type and Halpern-type that approximate a solution of a system of a generalized mixed equilibrium problem anda common fixed point of a countable family of totally quasi-C-asymptotically nonexpansivemulti-valued maps are constructed. Strong convergence of the sequence generated by thesealgorithms is proved in uniformly smooth and strictly convex real Banach spaces with Kadec-Klee property. Furthermore, several applications of our theorems are also presented. Finally,our theorems are significant improvements on several important recent results for this classof nonlinear problems. 展开更多
关键词 Halpern-type algorithm Krasnoselskii-type algorithm system of generalizedmixed equilibrium problems totally quasi-C-asymptotically nonexpansive multi-valued maps equally continuous maps
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ON THE SPECTRAL CHARACTERIZATION OF A STRONGLY CONTINUOUS PERTURBED SEMIGROUP
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作者 王海燕 阳名珠 《Acta Mathematica Scientia》 SCIE CSCD 1995年第S1期64-69,共6页
In this paper, we get a sufficient condition to estimate the essential type of a strongly continuous sendgroup in a Banach space, using oh condition we prove that the essential type of the strongly continuous semigro... In this paper, we get a sufficient condition to estimate the essential type of a strongly continuous sendgroup in a Banach space, using oh condition we prove that the essential type of the strongly continuous semigroup don't increase under the A-smoothing perturbation and establish the spectral mapping theorem for the asymptotic parts of the spectrum of generator and semgroup. 展开更多
关键词 Strongly continuous semigroup Spectral mapping theorem Essential type.
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Necessary Conditions for a Fixed Point of Maps in Non-Metric Spaces
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作者 I. Raykov 《Advances in Pure Mathematics》 2012年第6期371-372,共2页
The main purpose of the present work is to introduce necessary conditions for a map on a non-metric space, defined by using a map on a metric space, to have a fixed point.
关键词 Topological SPACE Complete Metric Compact SPACE CAUCHY Sequence LIPSCHITZ continuous map CONTRACTION map
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Weak KKM theorems in generalized finitely continuous space with applications
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作者 方勉 王磊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第10期1291-1296,共6页
Some new weak Knaster-Kuratouski-Mazurkiewicz (KKM) theorems are proved under the noncompact situation in the generalized finitely continuous space (GFC-space) without any convexity. As applications, the minimax i... Some new weak Knaster-Kuratouski-Mazurkiewicz (KKM) theorems are proved under the noncompact situation in the generalized finitely continuous space (GFC-space) without any convexity. As applications, the minimax inequalities of the Ky Fan type are also given under some suitable conditions. The results unify and generalize some known results in recent literatures. 展开更多
关键词 weak Knaster-Kuratouski-Mazurkiewicz (KKM) mapping generalized finitely continuous space (GFC-space) minimax inequality GFC-quasicovex
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p-order Feigenbaum's Maps
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作者 廖公夫 王立冬 张玉成 《Northeastern Mathematical Journal》 CSCD 2004年第3期284-290,共7页
A continuous map f from the unit closed interval into itself is called a p-order Feigenbaum's map if fp(λx) = λf(x),f(O)=1 and f|[λ,1] is univallecular. In this paper, some characterizations of p order Feigenba... A continuous map f from the unit closed interval into itself is called a p-order Feigenbaum's map if fp(λx) = λf(x),f(O)=1 and f|[λ,1] is univallecular. In this paper, some characterizations of p order Feigenbaum's maps are discussed and the existence for both types of such maps is proven. 展开更多
关键词 functional equation Feigenbaum's map continuous map
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An Efficient PRBG Based on Chaotic Map and Engel Continued Fractions
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作者 Atef Masmoudi William Puech Mohamed Salim Bouhlel 《Journal of Software Engineering and Applications》 2010年第12期1141-1147,共7页
In recent years, a variety of chaos-based cryptosystems have been proposed. Some of these systems are used in designing a pseudo random bit generator (PRBG) for stream cipher applications. Most of the chaotic systems ... In recent years, a variety of chaos-based cryptosystems have been proposed. Some of these systems are used in designing a pseudo random bit generator (PRBG) for stream cipher applications. Most of the chaotic systems used in cryptography have good chaotic properties like ergodicity, sensitivity to initial values and sensitivity to control parameters. However, some of them are not very suitable for use in cryptography because of their non-uniform density function, and their relatively small key space. To be used in cryptography, a PRBG may need to meet stronger requirements than for other applications. In particular, various statistical tests can be applied to the outputs of such generators to conclude whether the generator produces a truly random sequence or not. In this paper, we propose a PRBG based on the use of the standard chaotic map with large key space and the Engle Continued Fractions (ECF) map. The outputs of the standard map are used as the inputs of ECF-map. The chaotic nature of the standard map and the good statistical properties of the ECF map motivate us to design a new PRBG for stream cipher applications. The numerical simulation analysis indicates that our PRBG produces bit sequences possessing excellent statistical and cryptographic properties. 展开更多
关键词 CRYPTOGRAPHY continued FRACTION STATISTICAL TESTS PRBG CHAOTIC map
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On Common Fixed Point Theorem of Four Self Maps in a Fuzzy Metric Space
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作者 Manthena Prapoorna Manchala Rangamma 《Advances in Pure Mathematics》 2016年第5期303-308,共6页
In the present paper, we show that there exists a unique common fixed point for four self maps in a fuzzy metric space where two of the maps are reciprocally continuous and the other two maps are z-asymptotically comm... In the present paper, we show that there exists a unique common fixed point for four self maps in a fuzzy metric space where two of the maps are reciprocally continuous and the other two maps are z-asymptotically commuting. 展开更多
关键词 T-NORM Fuzzy Metric Space Reciprocally continuous Z - Asymptotically Commuting maps
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Analysis of the ITIL Mapping with COBIT over the Business Process Continuity Management
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作者 Melita Kozina 《Computer Technology and Application》 2011年第7期513-521,共9页
Planning and implementation as well as increased control over the Business Continuity Management (BCM) is a complex task in the company requiring adequate resources. BCM aims to reduce risks and develops plans for r... Planning and implementation as well as increased control over the Business Continuity Management (BCM) is a complex task in the company requiring adequate resources. BCM aims to reduce risks and develops plans for restoring business activities if they are interrupted by a disaster. The purpose of the paper is to analyze and describe two standards, Information Technology Infrastructure Library (ITIL) and Control Objectives for Information and Related Technology (COBIT), especially their mapping for the improved planning and implementation of the BCM as well as the increased control over the BCM activities. COBIT is used more as a management framework, providing management tools, such as control objectives, metrics and maturity models in order to complement the control framework. ITIL includes process steps and tasks because it is more oriented towards IT processes (process framework), defining the best practice for IT service management. Within this mapping, ITIL processes may be used to achieve and demonstrate compliance with COBIT control objectives for BCM process. 展开更多
关键词 Business continuity management (BCM) IT service information and related technology) ITIL (information technology continuity management (ITSCM) COBIT (control objectives for infrastructure library) mapping of ITIL with COBIT.
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节点拓扑变量非耦合映射的ICM方法
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作者 彭细荣 隋允康 郑勇刚 《力学学报》 EI CAS CSCD 北大核心 2024年第8期2468-2481,共14页
文章提出了节点拓扑变量一种非耦合映射的ICM方法,对于结构拓扑优化问题予以建模和求解:首先将基结构划分为由较小单元组成的网格,取节点独立、连续的拓扑变量,建立了一种双线性形函数插值的变量非耦合映射,替代了单元独立连续拓扑变量... 文章提出了节点拓扑变量一种非耦合映射的ICM方法,对于结构拓扑优化问题予以建模和求解:首先将基结构划分为由较小单元组成的网格,取节点独立、连续的拓扑变量,建立了一种双线性形函数插值的变量非耦合映射,替代了单元独立连续拓扑变量,使单元的“有”或“无”连续化近似,实现了节点拓扑变量过滤识别与物理量的单元内插值,推导建立了节点拓扑设计变量的优化模型,采用基于变量可分离的二阶对偶规划算法求解,并且改进了最优拓扑构型的圆整技术.接着以常见的位移约束下结构重量(或体积)极小拓扑优化问题为例,演示了上述建模及求解过程.最后分别给出了单载荷工况和多载荷工况下的位移约束拓扑优化的算例,数值计算结果验证了本方法的有效性.研究有如下优点:克服了以往基于单元拓扑变量研究的缺陷,即最优结构边界为锯齿形,得到的最优结构的拓扑边界光滑清晰;给出了节点拓扑变量和单元拓扑函数场定义,提炼出构造该场必须遵循的5点准则,克服了节点拓扑ICM方法有关研究中存在的不足;得到节点设计变量不再是耦合关系,可以方便地求出结构物理量的二阶导数,从而利用变量可分离对偶优化算法进行高效的寻优;研究成果不仅丰富了ICM方法的内涵,推动了其发展,而且对变密度的节点拓扑方法也有参考的裨益. 展开更多
关键词 结构拓扑优化 ICM方法 变量非耦合 节点拓扑变量
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