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Functional Equilibrium Between Photosynthetic and Above-ground Nonphotosynthetic Structures of Plants: Evidence from a Pruning Experiment with Three Subtropical Tree Species 被引量:4
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作者 曾波 《Acta Botanica Sinica》 CSCD 2003年第2期152-157,共6页
It is well known that plants have functional equilibrium between their above-ground parts (shoots) and below-ground parts (roots), but whether the above-ground parts of plants have functional equilibrium between their... It is well known that plants have functional equilibrium between their above-ground parts (shoots) and below-ground parts (roots), but whether the above-ground parts of plants have functional equilibrium between their photosynthetic structures (leaves) and non-photosynthetic structures (branches and stem) is unknown. The purpose of this study is to test the hypotheses that: (1) the above-ground parts of plants have functional equilibriums between their photosynthetic structures and non-photosynthetic structures; (2) the maintenance of the equilibriums is guaranteed by the alteration of biomass partitioning to photosynthetic and non-photosynthetic structures. To test these hypotheses, a pruning experiment with four pruning intensities (0%, 20%, 50%, and 70%) were carried out with three subtropical Chinese tree species ( Ficus microcarpa, Ficus virens, Cinnamomum camphora). Pruning treatments were conducted in two successive years. The results were in conformity with the hypothesis, i.e. above-ground parts of trees had functional equilibriums between photosynthetic and non-photosynthetic structures. Pruning decreased instantaneously the mass ratios of photosynthetic structures to non-photosynthetic structures (P/NP) of all three tree species, the reduction in P/NP was strengthened with pruning intensity. However, one year after pruning, the P/NP of all pruned trees increased and were not smaller than those of unpruned trees. In agreement with the expectation, the biomass partitioning of pruned trees was altered, more newly produced above-ground biomass was partitioned to leaf growth and less to branch and stem growth, thus enabled the damaged trees to restore their functional equilibrium between photosynthetic and non-photosynthetic structures. It is clear that the maintenance of functional equilibrium between photosynthetic and non-photosynthetic structures guaranteed by the alteration of biomass partitioning provides plants a good strategy to resist external disturbance and damage. 展开更多
关键词 biomass partitioning functional equilibrium non-photosynthetic structures photosynthetic structures tree
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Contribution of biodiversity to ecosystem functioning:a non-equilibrium thermodynamic perspective 被引量:1
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作者 Amit CHAKRABORTY B Larry LI 《Journal of Arid Land》 SCIE 2011年第1期71-74,共4页
Ecosystem stays far from thermodynamic equilibrium. Through the interactions among biotic and abiotic components, and encompassing physical environments, ecosystem forms a dissipative struc- ture that allows it to dis... Ecosystem stays far from thermodynamic equilibrium. Through the interactions among biotic and abiotic components, and encompassing physical environments, ecosystem forms a dissipative struc- ture that allows it to dissipate energy continuously and thereby remains functional over time. Biotic regulation of energy and material fluxes in and out of the ecosystem allows it to maintain a homeostatic state which corresponds to a self-organized state emerged in a non-equilibrium thermodynamic system. While the associated self-organizational processes approach to homeostatic state, entropy (a measure of irre- versibility) degrades and dissipation of energy increases. We propose here that at a homeostatic state of ecosystem, biodiversity which includes both phenotypic and functional diversity, attains optimal values. As long as biodiversity remains within its optimal range, the corresponding homeostatic state is maintained. However, while embedded environmental conditions fluctuate along the gradient of accelerating changes, phenotypic diversity and functional diversity contribute inversely to the associated self-organizing proc- esses. Furthermore, an increase or decrease in biodiversity outside of its optimal range makes the eco- system vulnerable to transition into a different state. 展开更多
关键词 ECOSYSTEM SELF-ORGANIZATION non-equilibrium thermodynamics functional diversity phenotypic diversity
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The construction of general basis functions in reweighting ensemble dynamics simulations: Reproduce equilibrium distribution in complex systems from multiple short simulation trajectories
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作者 张传彪 黎明 周昕 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期65-73,共9页
Ensemble simulations, which use multiple short independent trajectories from dispersive initial conformations, rather than a single long trajectory as used in traditional simulations, are expected to sample complex sy... Ensemble simulations, which use multiple short independent trajectories from dispersive initial conformations, rather than a single long trajectory as used in traditional simulations, are expected to sample complex systems such as biomolecules much more efficiently. The re-weighted ensemble dynamics(RED) is designed to combine these short trajectories to reconstruct the global equilibrium distribution. In the RED, a number of conformational functions, named as basis functions,are applied to relate these trajectories to each other, then a detailed-balance-based linear equation is built, whose solution provides the weights of these trajectories in equilibrium distribution. Thus, the sufficient and efficient selection of basis functions is critical to the practical application of RED. Here, we review and present a few possible ways to generally construct basis functions for applying the RED in complex molecular systems. Especially, for systems with less priori knowledge, we could generally use the root mean squared deviation(RMSD) among conformations to split the whole conformational space into a set of cells, then use the RMSD-based-cell functions as basis functions. We demonstrate the application of the RED in typical systems, including a two-dimensional toy model, the lattice Potts model, and a short peptide system. The results indicate that the RED with the constructions of basis functions not only more efficiently sample the complex systems, but also provide a general way to understand the metastable structure of conformational space. 展开更多
关键词 ensemble simulation equilibrium distribution reweighting basis functions PEPTIDE
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Alloy Gene Gibbs Energy Partition Function and Equilibrium Holographic Network Phase Diagrams of AuCu-Type Sublattice System 被引量:4
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作者 Youqing Xie Xiaobo Li +2 位作者 Xinbi Liu Yaozhuang Nie Hongjian Peng 《International Journal of Communications, Network and System Sciences》 2013年第10期415-442,共28页
Taking AuCu-sublattice system as an example, we present two discoveries and a method. First, the alloy gene sequences are the central characteristic atom sequences in the basic coordination cluster sequences. Second, ... Taking AuCu-sublattice system as an example, we present two discoveries and a method. First, the alloy gene sequences are the central characteristic atom sequences in the basic coordination cluster sequences. Second, the transmission mode of the information about structures and properties of the alloy genes is described by the alloy gene Gibbs energy partition function. The most valuable method in the system sciences is “the whole obtained from a few parts”. We have established the alloy gene database and holographic alloy positioning system of the Au-Cu system, as well as alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of the AuCu-type sublattice system. It means that a standard way for researchers to share predictive algorithms and computational methods may be produced during designing advanced alloys. 展开更多
关键词 ALLOY GENE Gibbs Energy PARTITION function HOLOGRAPHIC ALLOY POSITIONING System equilibrium
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Density functional calculation of equilibrium geometry and electronic structure of pyrite
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作者 邱冠周 肖奇 +1 位作者 胡岳华 徐竞 《中国有色金属学会会刊:英文版》 CSCD 2001年第4期583-586,共4页
The equilibrium geometry and electronic structure of pyrite has been studied using self consistent density functional theory within the local density approximation (LDA). The optimum bulk geometry is in good agreement... The equilibrium geometry and electronic structure of pyrite has been studied using self consistent density functional theory within the local density approximation (LDA). The optimum bulk geometry is in good agreement with crystallographic data. The calculated band structure and density of states in the region around the Fermi energy show that valence band maximum (VBM) is at X (100), and the conduction band minimum (CBM) is at G (000). The indirect and direct band gaps are 0.6?eV and 0.74?eV, respectively. The calculated contour map of difference of charge density shows excess charge in nonbonding d electron states on the Fe sites. The density increases between sulfur nuclei and between iron and sulfur nuclei qualitatively reveal that S-S bond and Fe-S bond are covalent binding. 展开更多
关键词 density functional calculation electronic structure equilibrium geometry PYRITE
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THE EQUILIBRIUM PROBLEM AND CAPACITY FOR JUMP MARKOV PROCESSES 被引量:1
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作者 Liu Luqin 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期15-30,共16页
Let X=(Ω,■,■,X_(t),θ_(t),P^(x))be a jump Markov process with q-pair q(x)-q(x,A).In this paper,the equilibrium principle is established and equilibrium functions,energy,capacity and related problems is investigated... Let X=(Ω,■,■,X_(t),θ_(t),P^(x))be a jump Markov process with q-pair q(x)-q(x,A).In this paper,the equilibrium principle is established and equilibrium functions,energy,capacity and related problems is investigated in terms of the q-pair q(x)-q(x,A). 展开更多
关键词 MARKOV PROCESS JUMP PROCESS equilibrium PRINCIPLE ENERGY CAPACITY equilibrium function
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基于新代数等价变换求解Fisher市场均衡问题的全牛顿步内点算法
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作者 迟晓妮 张璐 +1 位作者 刘三阳 张所滨 《工程数学学报》 北大核心 2026年第1期1-14,共14页
权互补问题是互补问题的一类重要推广,当权向量为零向量时,该问题就化为互补问题。非零权向量的存在使得权互补问题的理论和算法更为复杂。权互补问题的应用广泛,科学、经济等领域中的一大类均衡问题都可以转化为权互补问题进行求解,比... 权互补问题是互补问题的一类重要推广,当权向量为零向量时,该问题就化为互补问题。非零权向量的存在使得权互补问题的理论和算法更为复杂。权互补问题的应用广泛,科学、经济等领域中的一大类均衡问题都可以转化为权互补问题进行求解,比如Fisher市场均衡问题可化为一种斜对称的权互补问题。提出了一种求解Fisher市场均衡问题的线性权互补模型的新全牛顿步内点算法。基于中心方程的新代数等价变换形式,运用核函数φ(t)=t2计算搜索方向。该核函数首次被用于求解线性权互补问题。算法每次迭代仅使用一个全牛顿步,无需进行线搜索,节省运行内存。证明算法的收敛性及多项式复杂度,最后通过数值算例验证了算法的有效性。 展开更多
关键词 线性权互补问题 Fisher市场均衡 全牛顿步 内点算法 核函数 代数等价变换
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APPLICATION OF PENALTY FUNCTION METHOD IN ISOPARANIETRIC HYBRID FINITE ELEMENT ANALYSIS 被引量:1
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作者 CHEN Dao-zheng(陈道政) JIAO Zhao-ping(焦兆平) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第8期1017-1025,共9页
By the aid of the penalty function method, the equilibrium restriction conditions were introduced to the isoparametric hybrid finite element analysis, and the concrete application course of the penalty function method... By the aid of the penalty function method, the equilibrium restriction conditions were introduced to the isoparametric hybrid finite element analysis, and the concrete application course of the penalty function method in three-dimensional isoparametdc hybrid finite element was discussed. The separated penalty parameters method and the optimal hybrid element model with penalty balance were also presented. The penalty balance method can effectively refrain the parasitical stress on the premise of no additional degrees of freedom. The numeric experiment shows that the presented element not only is effective in improving greatly the numeric calculation precision of distorted grids but also has the universality. 展开更多
关键词 hybrid element equilibrium restriction condition penalty function method
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The scientific foundation of Major Function Oriented Zoning in China 被引量:30
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作者 樊杰 李平星 《Journal of Geographical Sciences》 SCIE CSCD 2009年第5期515-531,共17页
Major function oriented zoning (MFOZ hereafter) is the guideline for optimizing the spatial pattern of regional development in China, which entails both theoretical and methodological innovation in the academic fiel... Major function oriented zoning (MFOZ hereafter) is the guideline for optimizing the spatial pattern of regional development in China, which entails both theoretical and methodological innovation in the academic field of economic geography. This study analyzes the basic features of territorial function and puts forward a spatial equilibrium model for regional development for the first time. It argues that there exists a trend of regional convergence in the average value which indicates the comprehensive development status of any region. Based on this finding, the study illustrates that the formation of functional zone should be conducive to the narrowing of regional gap and that free flow of resources between regions is the prerequisite to spatial equilibrium. It also investigates the impact of territorial functional evolution on the process of spatial equilibrium and suggests that the maximization of benefits derived from zoning proposal is interrelative with the method of regional division and the degree of understanding towards the temporal changes of territorial function. Furthermore, this study goes on to examine the scientific foundation of several issues concerning the reconciliation between contradictory functions of development and protection, the selection of indicators and the spatial and temporal features of MFOZ. It is then probes into the rationality of achieving dual goals of efficiency and equality simultaneously through three-dimensional flow and spatial equilibrium. The paper ends with discussions on the position, implementation and coordination of MFOZ from the perspective of institutional arrangements of spatial governance including law, planning and government policy. 展开更多
关键词 territorial function MFOZ regional development spatial equilibrium spatial governance spatialplanning regional policy
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Regional Stability of Positive Switched Linear Systems with Multi-equilibrium Points 被引量:2
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作者 Zhi Liu Yu-Zhen Wang 《International Journal of Automation and computing》 EI CSCD 2017年第2期213-220,共8页
This paper studies the regional stability for positive switched linear systems with multi-equilibrium points (PSLS-MEP). First, a sufficient condition is presented for the regional stability of PSLS-MEP via a common... This paper studies the regional stability for positive switched linear systems with multi-equilibrium points (PSLS-MEP). First, a sufficient condition is presented for the regional stability of PSLS-MEP via a common linear Lyapunov function. Second, by establishing multiple Lyapunov functions, a dwell time based condition is proposed for the regional stability analysis. Third, a suprasphere which contains all equilibrium points is constructed as a stability region of the considered PSLS-MEP, which is less conservative than existing results. Finally, the study of an illustrative example shows that the obtained results are effective in the regional stability analysis of PSLS-MEP. 展开更多
关键词 Regional stability positive switched linear system multi-equilibrium points common linear Lyapunov function multipleLyapunov function.
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Structures and electronic properties of Mo_(2n)N_n(n=1-5):a density functional study
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作者 陈杭 雷雪玲 +2 位作者 刘立仁 刘志锋 祝恒江 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期212-222,共11页
The lowest-energy structures and the electronic properties of Mo2nNn (n=1-5) clusters have been studied by using the density functional theory (DFT) simulating package DMol3 in the generalized gradient approximati... The lowest-energy structures and the electronic properties of Mo2nNn (n=1-5) clusters have been studied by using the density functional theory (DFT) simulating package DMol3 in the generalized gradient approximation (GGA). The resulting equilibrium geometries show that the lowest-energy structures are dominated by central cores which correspond to the ground states of Mon (n = 2, 4, 6, 8, 10) clusters and nitrogen atoms which surround these cores. The average binding energy, the adiabatic electron affinity (AEA), the vertical electron affinity (VEA), the adiabatic ionization potential (AIP) and the vertical ionization potential (VIP) of Mo2nNn (n=1-5) clusters have been estimated. The HOMO LUMO gaps reveal that the clusters have strong chemical activities. An analysis of Mulliken charge distribution shows that charge-transfer moves from Mo atoms to N atoms and increases with cluster size. 展开更多
关键词 Mo2nNn clusters density functional theory equilibrium structures electronic properties
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A Penalty Approach for Generalized Nash Equilibrium Problem 被引量:1
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作者 Hou JIAN LAI JUN-FENG 《Communications in Mathematical Research》 CSCD 2012年第2期181-192,共12页
The generalized Nash equilibrium problem (GNEP) is a generalization of the standard Nash equilibrium problem (NEP), in which both the utility function and the strategy space of each player depend on the strategies... The generalized Nash equilibrium problem (GNEP) is a generalization of the standard Nash equilibrium problem (NEP), in which both the utility function and the strategy space of each player depend on the strategies chosen by all other players. This problem has been used to model various problems in applications. However, the convergent solution algorithms are extremely scare in the literature. In this paper, we present an incremental penalty method for the GNEP, and show that a solution of the GNEP can be found by solving a sequence of smooth NEPs. We then apply the semismooth Newton method with Armijo line search to solve latter problems and provide some results of numerical experiments to illustrate the proposed approach. 展开更多
关键词 Nash equilibrium problem generalized Nash equilibrium problem log-arithmic barrier function quasi-variational inequality semismooth Newton method
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Combinatorial Model Involving Mixed Deterministic Freight Volume Distribution and User's Equilibrium Assignment
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作者 ZHOU Xi zhao (Management School , Shanghai Maritime University) 《Advances in Manufacturing》 SCIE CAS 1999年第4期325-330,共6页
Considering characteristics of Chinese urban mixed traffic,the author develops a combinatorial model involving the mixed deterministic traffic volume distribution and user's equilibrium (UE) assignment on the basi... Considering characteristics of Chinese urban mixed traffic,the author develops a combinatorial model involving the mixed deterministic traffic volume distribution and user's equilibrium (UE) assignment on the basis of symmetrical link travel time function (or deterrence).Its uniqueness and equivalance to the Wardropian principle of UE are also proved.Finally,we give the algorithm of model. 展开更多
关键词 link travel time function user's equilibrium urban mixed traffic traffic volume assignment
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Dynamic Analysis of a Predator-Prey Model with Holling-II Functional Response
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作者 Jiemin Mo Wanying Li +2 位作者 Donghuan He Songbo Wang Xiaoliang Zhou 《Journal of Applied Mathematics and Physics》 2023年第10期2871-2878,共8页
A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were d... A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were discussed. The results show that under certain limited conditions, these two groups can maintain a balanced position, which provides a theoretical reference for relevant departments to make decisions on ecological protection. 展开更多
关键词 Predator-Prey Model Holling-II functional Response equilibrium Point STABILITY
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Vapour–Liquid Equilibrium for N,N-Dimethylformamide + Benzene + Thiophene via Gibbs Ensemble Molecular Simulation
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作者 Aiwu Zeng Wenqi Chen +1 位作者 Jianjun Ma Jiang Yu 《Transactions of Tianjin University》 EI CAS 2017年第1期26-34,共9页
The selection and design of an optimal solvent for extractive distillation require reliable vapour-liquid phase equilibrium data and knowledge of extraction mechanisms.Compared with time-consuming experiments,molecula... The selection and design of an optimal solvent for extractive distillation require reliable vapour-liquid phase equilibrium data and knowledge of extraction mechanisms.Compared with time-consuming experiments,molecular simulation presents great potential in research on the properties of fluids.Therefore,in this work,Gibbs ensemble Monte Carlo was applied to successfully predict the vapour-liquid phase equilibrium data of binary and ternary systems containing benzene,thiophene and N,Ndimethylformamide(DMF) at P=101.3 kPa.The explicit hydrogen version of the transferable potentials for phase equilibria potential model was chosen for benzene and thiophene,whereas the OPLS potential model was selected for DMF.The predicted phase diagrams were compared with experimental data and the UNIQUAC thermodynamic model.A good agreement was obtained,which corroborated the validity of the potential models.In addition,the extraction mechanism was explored by radial distribution function(RDF) of the liquid-phase structure.The RDFs showed that thiophene and benzene shared a similar liquidphase structure because of the intermolecular interaction.The distinct difference between the RDFs of DMF/benzene and those of DMF/thiophene is that the oxygen atom of DMF is more associated with hydrogen atoms of thiophene than that of benzene,which may be responsible for the extraction effect of DMF. 展开更多
关键词 Gibbs ensemble Monte Carlo Vapour-liquid equilibrium DMF BENZENE THIOPHENE Radial distribution function
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Periodic Solutions for Functional Differential Inclusion with Nonconvex Right Hand Sides
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作者 吕显瑞 史少云 李晓光 《Northeastern Mathematical Journal》 CSCD 2003年第4期396-406,共11页
In this paper we present a general existence result of periodic solutions for functional differential inclusions with nonconvex right hand sides, by using the asymptotic fixed point theory. In our result, the uniform ... In this paper we present a general existence result of periodic solutions for functional differential inclusions with nonconvex right hand sides, by using the asymptotic fixed point theory. In our result, the uniform boundedness and ultimate boundedness are only assumed to the solutions with bounded initial functions. On the other hand, the dissipativity is sought on a suitable bounded convex subset of the state space of solutions. This becomes difficult for the systems with infinite delay since in this case the subset is probably not forward invariant for the orbits of solutions. These are also considerable even for the usual functional differential equations with infinite delay. As an application, we answer an open problem on the existence of an equilibrium state for multivalued permanent systems. 展开更多
关键词 functional differential inclusion periodic solution PERMANENCE equilibrium state
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A novel methodology for constructing a multi-wing chaotic and hyperchaotic system with a unified step function switching control 被引量:3
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作者 张朝霞 禹思敏 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期83-94,共12页
This paper aims at developing a novel method of constructing a class of multi-wing chaotic and hyperchaotic system by introducing a unified step function. In order to overcome the essential difficulties in iteratively... This paper aims at developing a novel method of constructing a class of multi-wing chaotic and hyperchaotic system by introducing a unified step function. In order to overcome the essential difficulties in iteratively adjusting multiple parameters of conventional multi-parameter control, this paper introduces a unified step function controlled by a single parameter for constructing various multi-wing chaotic and hyperchaotic systems. In particular, to the best of the authors' knowledge, this is also the first time to find a non-equilibrium multi-wing hyperchaotic system by means of the unified step function control. According to the heteroclinic loop Shilnikov theorem, some properties for multi-wing attractors and its chaos mechanism are further discussed and analyzed. A circuit for multi-wing systems is designed and implemented for demonstration, which verifies the effectiveness of the proposed approach. 展开更多
关键词 non-equilibrium multi-wing hyperchaotic system single parameter control unified step function circuit implementation
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地下装配式建筑施工工期-成本-碳排放的均衡优化 被引量:2
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作者 闫林君 王亚妮 +1 位作者 陈慧鑫 刘晶晶 《兰州大学学报(自然科学版)》 北大核心 2025年第3期357-363,共7页
为了地下装配式建筑施工关键要素的协调优化控制,以多属性效用函数为主,施工工期为决策变量,建立基于施工工期-成本-碳排放的均衡优化模型.通过分析施工工期-成本-碳排放要素之间的关系,将其以函数形式量化,构建地下装配式施工关键要素... 为了地下装配式建筑施工关键要素的协调优化控制,以多属性效用函数为主,施工工期为决策变量,建立基于施工工期-成本-碳排放的均衡优化模型.通过分析施工工期-成本-碳排放要素之间的关系,将其以函数形式量化,构建地下装配式施工关键要素的均衡优化目标函数.基于地下装配式施工对关键要素的作用机理,利用网络层次分析法确定均衡优化函数的决策偏好系数,用多种群蚁群协同进化算法得到均衡优化模型的最优解,并在整体模型的最优解下得到各关键要素的较优解.以实例构建施工任务均衡优化函数并进行优化分析.结果表明,当最优效用值μ=0.86时,预制构件关键要素达到均衡最优;当μ=0.87时,现场装配与吊装关键要素达到均衡最优;当μ=0.90时,后浇混凝土关键要素达到均衡最优;当μ=0.86时,养护关键要素达到均衡最优.结论验证了构建的均衡优化函数的合理性以及算法对求解模型的有效性. 展开更多
关键词 地下装配式建筑 关键要素 均衡优化 多属性效用函数 多种群蚁群协同进化算法
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一种子类不平衡的乳腺病理图像多分类方法
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作者 刘敏 何智子 +1 位作者 胡兰兰 林坤 《湖北工业大学学报》 2025年第4期30-36,共7页
针对乳腺病理图像数据集子类不平衡及子类差异细微的问题,提出了一种面向子类不平衡的乳腺病理图像多分类方法。数据层面,引入LR-SMOTE算法平衡样本数量;算法层面,首先为了改善子类差异细微,难以精细多分类的问题,融合位置注意力机制和... 针对乳腺病理图像数据集子类不平衡及子类差异细微的问题,提出了一种面向子类不平衡的乳腺病理图像多分类方法。数据层面,引入LR-SMOTE算法平衡样本数量;算法层面,首先为了改善子类差异细微,难以精细多分类的问题,融合位置注意力机制和通道注意力机制,建立了非局部均衡注意力模型,其次,为了进一步均衡子类不平衡,Focal loss函数进行了优化改进。实验结果表明,所研究的方法具有较高分类精度,对不区分放大倍数的图像,准确度可达到97.69%,召回率可达到97.71%,对放大倍数为40×、100×、200×和400×的图像,比同类研究方法准确率均提高了0.59%以上,召回率提高了1.58%以上。 展开更多
关键词 不平衡数据 均衡损失函数 注意力机制 乳腺癌分类
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Empirical Equilibrium Beach Profiles Along the Eastern Tombolo of Giens
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作者 Minh Tuan Vu Yves Lacroix Viet Thanh Nguyen 《Journal of Marine Science and Application》 CSCD 2018年第2期241-253,共13页
Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion.Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the conc... Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion.Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile(EBP)could be useful in finding the most suitable measure to address the erosion problem.Field investigation data of 11 beaches along the eastern tombolo were supplied for this study,and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP.All of the observed beach profiles could be described by a single function,but a single EBP was inadequate to represent all of the beach profiles observed.The variation found could be explained in terms of longshore variation of bathymetry,sediment size,and wave parameters.Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters. 展开更多
关键词 equilibriumbeachprofile EasterntomboloofGiens Exponentialfunction Logarithmicfunction Potentialfunction erosion and ACCRETION
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