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DISSIPATION-BASED CONSISTENT RATE-DEPENDENT MODEL FOR CONCRETE 被引量:1
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作者 Fei Leng Gao Lin 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第2期147-155,共9页
An energy-dissipation based viscoplastic consistency model is presented to describe the performance of concrete under dynamic loading. The development of plasticity is started with the thermodynamic hypotheses in orde... An energy-dissipation based viscoplastic consistency model is presented to describe the performance of concrete under dynamic loading. The development of plasticity is started with the thermodynamic hypotheses in order that the model may have a sound theoretical background. Independent hardening and softening and the rate dependence of concrete are described separately for tension and compression. A modified implicit backward Euler integration scheme is adopted for the numerical computation. Static and dynamic behavior of the material is illustrated with certain numerical examples at material point level and structural level, and compared with existing experimental data. Results validate the effectiveness of the model. 展开更多
关键词 constitutive model VISCOPLASTICITY consistency model energy dissipation rate dependency CONCRETE backward Euler scheme
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Thermodynamic Consistency of Plate and Shell Mathematical Models in the Context of Classical and Non-Classical Continuum Mechanics and a Thermodynamically Consistent New Thermoelastic Formulation 被引量:3
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作者 Karan S. Surana Sri Sai Charan Mathi 《American Journal of Computational Mathematics》 2020年第2期167-220,共54页
Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived ... Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived using the conservation and balance laws of continuum mechanics in conjunction with the corresponding kinematic assumptions. This is referred to as thermodynamic consistency of the mathematical models. Thermodynamic consistency ensures thermodynamic equilibrium during the evolution of the deformation. When the mathematical models are thermodynamically consistent, the second law of thermodynamics facilitates consistent derivations of constitutive theories in the presence of dissipation and memory mechanisms. This is the main motivation for the work presented in this paper. In the currently used mathematical models for plates/shells based on the assumed kinematic relations, energy functional is constructed over the volume consisting of kinetic energy, strain energy and the potential energy of the loads. The Euler’s equations derived from the first variation of the energy functional for arbitrary length when set to zero yield the mathematical model(s) for the deforming plates/shells. Alternatively, principle of virtual work can also be used to derive the same mathematical model(s). For linear elastic reversible deformation physics with small deformation and small strain, these two approaches, based on energy functional and the principle of virtual work, yield the same mathematical models. These mathematical models hold for reversible mechanical deformation. In this paper, we examine whether the currently used plate/shell mathematical models with the corresponding kinematic assumptions can be derived using the conservation and balance laws of classical or non-classical continuum mechanics. The mathematical models based on Kirchhoff hypothesis (classical plate theory, CPT) and first order shear deformation theory (FSDT) that are representative of most mathematical models for plates/shells are investigated in this paper for their thermodynamic consistency. This is followed by the details of a general and higher order thermodynamically consistent plate/shell thermoelastic mathematical model that is free of a priori consideration of kinematic assumptions and remains valid for very thin as well as thick plates/shells with comprehensive nonlinear constitutive theories based on integrity. Model problem studies are presented for small deformation behavior of linear elastic plates in the absence of thermal effects and the results are compared with CPT and FSDT mathematical models. 展开更多
关键词 Plate and Shell Mathematical models Energy Functional Thermodynamic consistency Classical Continuum Mechanics Non-Classical Continuum Mechanics Internal Rotations Cosserat Rotations Principle of Virtual Work
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Relativistic Consistent Angular-Momentum Projected Shell-Model:Angular-Momentum Projection 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期579-582,共4页
The angular-momentum projection part of RECAPS is presented.Application of RECAPS to some deformed nuclei is also presented.
关键词 角动量投影 角动量投影壳模型 RECAPS-RMF 哈密顿量 相对论平均场 原子核物理
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Relativistic Consistent Angular-Momentum Projected Shell-Model: Relativistic Mean Field 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期429-434,共6页
We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shellmodel (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method.... We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shellmodel (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method.In this new model, nuclear ground-state properties are first calculated consistently using relativistic mean-field (RMF)theory. Then angular momentum projection method is used to project out states with good angular momentum from a few important configurations. By diagonalizing the hamiltonian, the energy levels and wave functions are obtained.This model is a new attempt for the understanding of nuclear structure of normal nuclei and for the prediction of nuclear properties of nuclei far from stability. In this paper, we will describe the treatment of the relativistic mean field. A computer code, RECAPS-RMF, is developed. It solves the relativistic mean field with axial-symmetric deformation in the spherical harmonic oscillator basis. Comparisons between our calculations and existing relativistic mean-field calculations are made to test the model. These include the ground-state properties of spherical nuclei ^16O and ^208Pb,the deformed nucleus 20~Ne. Good agreement is obtained. 展开更多
关键词 相对论核子结构模式 发射壳模式 PECAPS-RMF 相对论连贯角动量发射壳模式 原子核物理学
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Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims
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作者 LIU Zai-ming GENG Bing-zhen WANG Shi-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期98-113,共16页
Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair... Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily dependent.Under some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite interval.If we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval. 展开更多
关键词 bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability
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Thermodynamically consistent model for diblock copolymer melts coupled with an electric field
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作者 沈晓文 王奇 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期710-714,共5页
We present a thermodynamically consistent model for diblock copolymer melts coupled with an electric field derived using the Onsager linear response theory.We compare the model with the thermodynamically inconsistent ... We present a thermodynamically consistent model for diblock copolymer melts coupled with an electric field derived using the Onsager linear response theory.We compare the model with the thermodynamically inconsistent one previously used for the coupled system to highlight their differences in describing transient dynamics. 展开更多
关键词 thermodynamical consistency diblock copolymer melts electric field phase field model
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Measurement.Based Spatial-Consistent Channel Modeling Involving Clusters of Scatterers
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作者 YIN Xuefeng ZHANG Nan +1 位作者 Stephen Wang CHENG Xiang 《ZTE Communications》 2017年第1期28-34,共7页
In this paper,the conventional method of establishing spatial channel models(SCMs)based on measurements is extended by including clusters-of-scatterers(CoSs)that exist along propagation paths.The channel models result... In this paper,the conventional method of establishing spatial channel models(SCMs)based on measurements is extended by including clusters-of-scatterers(CoSs)that exist along propagation paths.The channel models resulted utilizing this new method are applicable for generating channel realizations of reasonable spatial consistency,which is required for designing techniques and systems of the fifth generation wireless communications.The scatterers’locations are estimated from channel measurement data obtained using large-scale antenna arrays through the Space-Alternating Generalized Expectation-Maximization(SAGE)algorithm derived under a spherical wavefront assumption.The stochastic properties of CoSs extracted from real measurement data in an indoor environment are presented. 展开更多
关键词 channel modeling large-scale antenna array spatial consistency space-alternating generalized expectation-maximization(SAGE) algorithm spherical wavefront
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Self-Consistent Model for Pulsed Direct-Current N_2 Glow Discharge
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作者 刘成森 王德真 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第2期2745-2747,共3页
A self-consistent analysis of a pulsed direct-current (DC) N2 glow discharge is presented. The model is based on a numerical solution of the continuity equations for electron and ions coupled with Poisson's equati... A self-consistent analysis of a pulsed direct-current (DC) N2 glow discharge is presented. The model is based on a numerical solution of the continuity equations for electron and ions coupled with Poisson's equation. The spatial-temporal variations of ionic and electronic densities and electric field are obtained. The electric field structure exhibits all the characteristic regions of a typical glow discharge (the cathode fall, the negative glow, and the positive column). Current-voltage characteristics of the discharge can be obtained from the model. The calculated current-voltage results using a constant secondary electron emission coefficient for the gas pressure 133.32 Pa are in reasonable agreement with experiment. 展开更多
关键词 pulsed DC glow discharge plasma nitriding self-consistent model
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CONSISTENCY OF LS ESTIMATOR IN SIMPLE LINEAR EV REGRESSION MODELS 被引量:12
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作者 刘继学 陈希孺 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期50-58,共9页
Consistency of LS estimate of simple linear EV model is studied. It is shown that under some common assumptions of the model, both weak and strong consistency of the estimate are equivalent but it is not so for quadra... Consistency of LS estimate of simple linear EV model is studied. It is shown that under some common assumptions of the model, both weak and strong consistency of the estimate are equivalent but it is not so for quadratic-mean consistency. 展开更多
关键词 EV model consistENCY
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Distributed model predictive control for multiagent systems with improved consistency 被引量:2
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作者 Shanbi WEI Yi CHAI Baocang DING 《控制理论与应用(英文版)》 EI 2010年第1期117-122,共6页
This paper addresses an improved distributed model predictive control (DMPC) scheme for multiagent systems with an attempt to improving its consistency. The deviation between what an agent is actually doing and what... This paper addresses an improved distributed model predictive control (DMPC) scheme for multiagent systems with an attempt to improving its consistency. The deviation between what an agent is actually doing and what its neighbors believe that agent is doing is penalized in the cost function of each agent. At each sampling instant the compatibility constraint of each agent is set tighter than the previous sampling instant. Like the traditional approach, the performance cost is utilized as the Lyapunov function to prove closed-looped stability. The closed-loop stability is guaranteed if the weight matrix for deviation in the cost function are sufficiently large. The proposed distributed control scheme is formulated as quadratic programming with quadratic constraints. A numerical example is given to illustrate the effectiveness of the proposed scheme. 展开更多
关键词 Distributed model predictive control (DMPC) Multiagent systems Compatibility constraint consistENCY
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Rate of strong consistency of the maximum quasi-likelihood estimator in quasi-likelihood nonlinear models 被引量:2
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作者 XIA Tian KONG Fan-chao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期391-400,共10页
Quasi-likelihood nonlinear models (QLNM) include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation (MQLE) ... Quasi-likelihood nonlinear models (QLNM) include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation (MQLE) is obtained in QLNM. In an important case, this rate is O(n-^1/2(loglogn)^1/2), which is just the rate of LIL of partial sums for i.i.d variables, and thus cannot be improved anymore. 展开更多
关键词 maximum quasi-likelihood estimator quasi-likelihood nonlinear models strong consistency
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Consistency Problem with Tracer Advection in the Atmospheric Model GAMIL 被引量:1
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作者 张恺 万慧 +1 位作者 王斌 张美根 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第2期306-318,共13页
The radon transport test, which is a widely used test case for atmospheric transport models, is carried out to evaluate the tracer advection schemes in the Grid-Point Atmospheric Model of IAP-LASG (GAMIL). Two of th... The radon transport test, which is a widely used test case for atmospheric transport models, is carried out to evaluate the tracer advection schemes in the Grid-Point Atmospheric Model of IAP-LASG (GAMIL). Two of the three available schemes in the model are found to be associated with significant biases in the polar regions and in the upper part of the atmosphere, which implies potentially large errors in the simulation of ozone-like tracers. Theoretical analyses show that inconsistency exists between the advection schemes and the discrete continuity equation in the dynamical core of GAMIL and consequently leads to spurious sources and sinks in the tracer transport equation. The impact of this type of inconsistency is demonstrated by idealized tests and identified as the cause of the aforementioned biases. Other potential effects of this inconsistency are also discussed. Results of this study provide some hints for choosing suitable advection schemes in the GAMIL model. At least for the polax-region-concentrated atmospheric components and the closely correlated chemical species, the Flux-Form Semi-Lagrangian advection scheme produces more reasonable simulations of the large-scale transport processes without significantly increasing the computational expense. 展开更多
关键词 numerical climate modelling tracer transport advection scheme consistENCY
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3-D consistency dynamic constitutive model of concrete 被引量:4
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作者 Xiao Shiyun,Li Hongnan and Lin Gao School of Hydraulic Engineering,Dalian University of Technology,Dalian 116024,China 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第2期233-246,共14页
Based on the consistency-viscoplastic constitutive model,the static William-Warnke model with three-parameters is modified and a consistency-viscoplastic William-Warnke model with three-parameters is developed that co... Based on the consistency-viscoplastic constitutive model,the static William-Warnke model with three-parameters is modified and a consistency-viscoplastic William-Warnke model with three-parameters is developed that considers the effect of strain rates. Then,the tangent modulus of the consistency viscoplastic model is introduced and an implicit backward Elure iterative algorithm is developed. Comparisons between the numerical simulations and experimental data show that the consistency model properly provides the uniaxial and biaxial dynamic behaviors of concrete. To study the effect of strain rates on the dynamic response of concrete structures,the proposed model is used in the analysis of the dynamic response of a simply-supported beam and the results show that the strain rate has a significant effect on the displacement and stress magnitudes and distributions. Finally,the seismic responses of a 278 m high arch dam are obtained and compared by using the linear elastic model,as well as rate-independent and rate-dependent William-Warnke three-parameter models. The results indicate that the strain rate affects the first principal stresses,and the maximal equivalent viscoplastic strain rate of the arch dam. Numerical calculations and analyses reveal that considering the strain rate is important in the safety assessments of arch dams located in seismically active areas. 展开更多
关键词 CONCRETE strain rate constitutive model consistency-viscoplastic William-Warnke three-parameter model algorithm arch dams seismic responsesimulation
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Separation work analysis of cohesive law and consistently coupled cohesive law
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作者 何铭华 辛克贵 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第11期1437-1446,共10页
An appropriate coupled cohesive law for predicting the mixed mode failure is established by combining normal separation and tangential separation of surfaces in the cohesive zone model (CZM) and the cohesive element... An appropriate coupled cohesive law for predicting the mixed mode failure is established by combining normal separation and tangential separation of surfaces in the cohesive zone model (CZM) and the cohesive element method. The Xu-Needleman exponential cohesive law with the fully shear failure mechanism is one of the most popular models. Based on the proposed consistently coupled rule/principle, the Xu-Needleman law with the fully shear failure mechanism is proved to be a non-consistently coupled cohesive law by analyzing the surface separation work. It is shown that the Xu-Needleman law is only valid in the mixed mode fracture when the normal separation work equals the tangential separation work. Based on the consistently coupled principle and the modification of the Xu-Needleman law, a consistently coupled cohesive (CCC) law is given. It is shown that the proposed CCC law has already overcome the non-consistency defect of the Xu-Needleman law with great promise in mixed mode analyses. 展开更多
关键词 cohesive element cohesive zone model (CZM) cohesive law separation work analysis consistently coupled rule/principle consistently Coupled cohesive (CCC) law non-consistently coupled cohesive law
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Group Decision-Making Method with Incomplete Intuitionistic Fuzzy Preference Relations Based on a Generalized Multiplicative Consistent Concept
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作者 Xiaoyun Lu Jiuying Dong +1 位作者 Hecheng Li Shuping Wan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第9期881-907,共27页
Based on the analyses of existing preference group decision-making(PGDM)methods with intuitionistic fuzzy preference relations(IFPRs),we present a new PGDM framework with incomplete IFPRs.A generalized multiplicative ... Based on the analyses of existing preference group decision-making(PGDM)methods with intuitionistic fuzzy preference relations(IFPRs),we present a new PGDM framework with incomplete IFPRs.A generalized multiplicative consistent for IFPRs is defined,and a mathematical programming model is constructed to supplement the missing values in incomplete IFPRs.Moreover,in this study,another mathematical programming model is constructed to improve the consistency level of unacceptably multiplicative consistent IFPRs.For group decisionmaking(GDM)with incomplete IFPRs,three reliable sources influencing the weights of experts are identified.Subsequently,a method for determining the weights of experts is developed by simultaneously considering three reliable sources.Furthermore,a targeted consensus process(CPR)is developed in this study with reference to the actual situation of the consensus level of each IFPR.Meanwhile,in response to the proposed multiplicative consistency definition,a novel method for determining the optimal priority weights of alternatives is redefined.Lastly,based on the above theory,a novel GDM method with incomplete IFPRs is developed,and the comparative and sensitivity analysis results demonstrate the utility and superiority of this work. 展开更多
关键词 Intuitionistic fuzzy preference relations multiplicative consistency CONSENSUS optimization model group decision-making
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A Nonstandard Computational Investigation of SEIR Model with Fuzzy Transmission, Recovery and Death Rates
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作者 Ahmed H.Msmali Fazal Dayan +3 位作者 Muhammad Rafiq Nauman Ahmed Abdullah Ali H.Ahmadini Hassan A.Hamali 《Computers, Materials & Continua》 SCIE EI 2023年第11期2251-2269,共19页
In this article,a Susceptible-Exposed-Infectious-Recovered(SEIR)epidemic model is considered.The equilibrium analysis and reproduction number are studied.The conventional models have made assumptions of homogeneity in... In this article,a Susceptible-Exposed-Infectious-Recovered(SEIR)epidemic model is considered.The equilibrium analysis and reproduction number are studied.The conventional models have made assumptions of homogeneity in disease transmission that contradict the actual reality.However,it is crucial to consider the heterogeneity of the transmission rate when modeling disease dynamics.Describing the heterogeneity of disease transmission mathematically can be achieved by incorporating fuzzy theory.A numerical scheme nonstandard,finite difference(NSFD)approach is developed for the studied model and the results of numerical simulations are presented.Simulations of the constructed scheme are presented.The positivity,convergence and consistency of the developed technique are investigated using mathematical induction,Jacobean matrix and Taylor series expansions respectively.The suggested scheme preserves all these essential characteristics of the disease dynamical models.The numerical and simulation results reveal that the proposed NSFD method provides an adequate representation of the dynamics of the disease.Moreover,the obtained method generates plausible predictions that can be used by regulators to support the decision-making process to design and develop control strategies.Effects of the natural immunity on the infected class are studied which reveals that an increase in natural immunity can decrease the infection and vice versa. 展开更多
关键词 Epidemic model fuzzy parameters NSFD scheme CONVERGENCE POSITIVITY consistENCY
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Strong Consistency of Estimators of a Semiparametric Regression Model under Fixed Design
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作者 TIAN Ping XUE Liu-gen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期202-209,共8页
在这份报纸,我们在固定设计下面考虑下列 semiparametric 回归模型:yi = x'i+g (xi )+ei。评估者, g (
关键词 半参变量衰退模型 最小正方估值 重量函数 强连贯性
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Some Mathematical Properties of the Dynamically Inconsistent Bellman Equation: A Note on the Two-Sided Altruism Dynamics
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作者 Aoki Takaaki 《Journal of Mathematics and System Science》 2015年第1期1-16,共16页
关键词 利他主义 双面 方程 贝尔 特性 数学 动力问题 压缩映射
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考虑优化调度的微电网频率恢复分布式预测控制策略
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作者 钟鸣 韩如磊 王宇强 《科学技术与工程》 北大核心 2024年第8期3308-3319,共12页
为了解决快速频率恢复和缓慢实际功率调度之间的时间尺度分离问题,提出一种考虑优化调度的微电网频率恢复分布式预测控制策略。引入的一致性策略能够在同一时间尺度上处理优化调度和频率恢复,另外提出的实际功率调度方案分布式模型预测... 为了解决快速频率恢复和缓慢实际功率调度之间的时间尺度分离问题,提出一种考虑优化调度的微电网频率恢复分布式预测控制策略。引入的一致性策略能够在同一时间尺度上处理优化调度和频率恢复,另外提出的实际功率调度方案分布式模型预测控制解决了通信延迟、通信中断和即插即用情景,并且将下垂、实际功率传输和相位角方程作为等式约束,从而预测每个微电网的行为。此外,终端值和不等式约束有助于确定可行解空间的界,从而减少优化时间。在4种测试情景下对控制器的动态性能进行实验评估,结果证明该控制器对负载变化和通信问题具有较强的鲁棒性,并且保证了频率快速回复与高效功率调度。 展开更多
关键词 一致性策略 分布式微电网 模型预测控制 功率调度
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富文本协同编辑中基于树型结构地址空间转换的一致性维护
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作者 刘亚 韩建功 +1 位作者 高丽萍 曲博 《小型微型计算机系统》 CSCD 北大核心 2024年第2期367-373,共7页
协同编辑通过多用户远程实时编辑,最大程度的支持团队之间的协作和交流.撤销操作作为协同编辑的一个重要特性,通过错误恢复简化协作编辑过程中产生的错误或者意外操作的处理过程.富文本编辑采用树型结构来进行文档管理,从而产生了较线... 协同编辑通过多用户远程实时编辑,最大程度的支持团队之间的协作和交流.撤销操作作为协同编辑的一个重要特性,通过错误恢复简化协作编辑过程中产生的错误或者意外操作的处理过程.富文本编辑采用树型结构来进行文档管理,从而产生了较线性文档更为复杂的并发操作环境和冲突消解场景.为了解决富文本文档中的并发操作环境与撤销操作冲突问题,本文提出了一种新颖的基于树型结构的地址空间转换方法,采用基于位置的节点寻址方案和节点属性值计数器策略,能更方便地支持撤销操作与更改操作.此外,本文还给出了树型结构地址空间的结果一致性的正确性证明及详细的案例分析,并开发了Web平台下实时协同富文本编辑原型系统AST-RichText,进一步验证了该方法的可行性. 展开更多
关键词 计算机支持的协同工作 实时协同编辑 地址空间转换 一致性模型 UNDO 树型文档
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