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H∞Optimal Output Regulation of Unknown Linear Systems via an Adaptive Dynamic Programming and Internal Model 认领 引用
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作者 Yong-Sheng Ma Jian Sun Yong Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第6期1314-1324,共11页
This paper delves into the H∞optimal output regulation problem for continuous-time linear systems with an unknown system model.By integrating the internal model principle with optimal control,we derive an optimal con... This paper delves into the H∞optimal output regulation problem for continuous-time linear systems with an unknown system model.By integrating the internal model principle with optimal control,we derive an optimal control policy and a worst-case disturbance policy through the formulation and solution of a zero-sum game problem.Subsequently,leveraging adaptive dynamic programming,we propose a policy iteration learning algorithm capable of learning both the optimal control policy and the worst-case disturbance policy directly from system data.The existing algorithms necessitate an initial stabilizing policy,a full-rank condition,and the storage of historical data to guarantee algorithm convergence.In contrast,we design a dual policy iteration algorithm equipped with an online learning mechanism,thereby eliminating these additional prerequisites.Simulation results with an antonomous ground vehicle underscore the effectiveness of our proposed algorithm,and its superiority is further demonstrated through comparisons with existing methodologies. 展开更多
关键词 Adaptive dynamic programming internal model principle optimal control output regulation
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Lagged effects of risk factors on the disability of older adults:A distributed lag non-linear model approach 认领 引用 被引量：1
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作者 Yitong Mao Zhiting Guo +2 位作者 Wen Gao Yuping Zhang Jingfen Jin 《International Journal of Nursing Sciences》 CSCD 2026年第1期53-60,I0004,I0005,共8页
Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and ... Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and Retirement Longitudinal Study(CHARLS).After feature selection via Elastic Net Regularization,we applied DLNMs to evaluate the lagged effects of risk factors.Disability was defined as the presence of any difficulties in basic activities of daily living(BADL).The cumulative relative risk(CRR)was calculated by summing the lag-specific risk estimates,representing the cumulative disability risk over the specified lag period.Effect modifications and sensitivity analyses were also performed.Results This study included a total of 2,318 participants.Early-phase lag factors,such as the difficulty in stooping(CRR=3.58;95%CI:2.31-5.55;P<0.001)and walking(CRR=2.77;95%CI:1.39-5.55;P<0.001),exerted the strongest effects immediately upon occurrence.Mid-phase lag factors,such as arthritis(CRR=1.51;95%CI:1.10-2.06;P=0.001),showed a resurgence in disability risk within 2-3 years.Late-phase lag factors,including depressive symptoms(CRR=2.38;95%CI:1.30-4.35;P<0.001)and elevated systolic blood pressure(CRR=1.64;95%CI:1.06-2.79;P=0.02),exhibited significant long-term cumulative risks.Conversely,grip strength(CRR=0.80;95%CI:0.54-0.95;P=0.02)and social participation(CRR=0.89;95%CI:0.73-0.99;P=0.04)were significant protective factors.Conclusions The findings underscore the importance of tailored interventions that account for various lag characteristics of different factors to effectively mitigate disability risk.Future studies should explore the underlying biological and sociological mechanisms of these lagged effects,identify intervention strategies that target risk factors with different lagged patterns,and evaluate their effectiveness. 展开更多
关键词 Ageing Disability Distributed lag non-linear models Nusing Risk factors
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Mixed integer programming modeling for the satellite three-dimensional component assignment and layout optimization problem 认领 引用
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作者 Yufeng XIA Xianqi CHEN +3 位作者 Zhijia LIU Weien ZHOU Wen YAO Zhongneng ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2025年第6期427-447,共21页
Satellite Component Layout Optimization(SCLO) is crucial in satellite system design.This paper proposes a novel Satellite Three-Dimensional Component Assignment and Layout Optimization(3D-SCALO) problem tailored to en... Satellite Component Layout Optimization(SCLO) is crucial in satellite system design.This paper proposes a novel Satellite Three-Dimensional Component Assignment and Layout Optimization(3D-SCALO) problem tailored to engineering requirements, aiming to optimize satellite heat dissipation while considering constraints on static stability, 3D geometric relationships between components, and special component positions. The 3D-SCALO problem is a challenging bilevel combinatorial optimization task, involving the optimization of discrete component assignment variables in the outer layer and continuous component position variables in the inner layer,with both influencing each other. To address this issue, first, a Mixed Integer Programming(MIP) model is proposed, which reformulates the original bilevel problem into a single-level optimization problem, enabling the exploration of a more comprehensive optimization space while avoiding iterative nested optimization. Then, to model the 3D geometric relationships between components within the MIP framework, a linearized 3D Phi-function method is proposed, which handles non-overlapping and safety distance constraints between cuboid components in an explicit and effective way. Subsequently, the Finite-Rectangle Method(FRM) is proposed to manage 3D geometric constraints for complex-shaped components by approximating them with a finite set of cuboids, extending the applicability of the geometric modeling approach. Finally, the feasibility and effectiveness of the proposed MIP model are demonstrated through two numerical examples"and a real-world engineering case, which confirms its suitability for complex-shaped components and real engineering applications. 展开更多
关键词 Mixed integer programming modeling Three-dimensional component assignment Layout optimization Phi-function Finite-rectangle method
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Developed Time-OptimalModel Predictive Static Programming Method with Fish Swarm Optimization for Near-Space Vehicle 认领 引用
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作者 Yuanzhuo Wang Honghua Dai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第5期1463-1484,共22页
To establish the optimal reference trajectory for a near-space vehicle under free terminal time,a time-optimal model predictive static programming method is proposed with adaptive fish swarm optimization.First,the mod... To establish the optimal reference trajectory for a near-space vehicle under free terminal time,a time-optimal model predictive static programming method is proposed with adaptive fish swarm optimization.First,the model predictive static programming method is developed by incorporating neighboring terms and trust region,enabling rapid generation of precise optimal solutions.Next,an adaptive fish swarm optimization technique is employed to identify a sub-optimal solution,while a momentum gradient descent method with learning rate decay ensures the convergence to the global optimal solution.To validate the feasibility and accuracy of the proposed method,a near-space vehicle example is analyzed and simulated during its glide phase.The simulation results demonstrate that the proposed method aligns with theoretical derivations and outperforms existing methods in terms of convergence speed and accuracy.Therefore,the proposed method offers significant practical value for solving the fast trajectory optimization problem in near-space vehicle applications. 展开更多
关键词 Near-space vehicle model predictive static programming neighboring term and trust region optimal control adaptive fish swarm optimization
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Research on the deployment model of intelligent highway sensor network under a bilevel programming framework 认领 引用
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作者 Yaoyao Hu Tong Han +3 位作者 Peng Wang Liang Wang Luyu Zhang Zhenhua Mou 《Digital Transportation and Safety》 2025年第1期31-41,共11页
Theoretical frameworks for the strategic placement of Road Side Units(RSUs)along highways are currently insufficient.In the context of emerging Vehicleto-Vehicle(V2V)and Vehicle-to-Infrastructure(V2I)communication set... Theoretical frameworks for the strategic placement of Road Side Units(RSUs)along highways are currently insufficient.In the context of emerging Vehicleto-Vehicle(V2V)and Vehicle-to-Infrastructure(V2I)communication settings,the impact of the growing presence of smart vehicles on the existing deployment strategy has been overlooked.The current paper therefore introduces a framework for optimizing RSU placement that accounts for the influence of V2V and V2I interactions.To optimize the advantages provided by RSU,the enhancement of RSU deployment scope is realized by leveraging the relay and forwarding capabilities inherent in V2V communications,which helps identify the most efficient deployment intervals,thereby reducing costs.After ascertaining how the intelligent vehicle's transmission range affects the time taken for flooding and recognizing the influence of packet length on the sensor network's energy usage,a novel bilevel programming framework has been introduced.The upper layer model minimizes the flooding time by setting the optimal intelligent vehicle transmission radius.In contrast the lower layer model,under the influence of the upper layer model,maximizes the energy efficiency of the sensing network by setting the optimal packet length.In addition,the conventional interlinking of information and traffic flow theories is restructured for RSU placement,innovatively modeling the benefits throughout the information lifecycle.Regarding information transmission loss,a node energy loss model is determined based on the bilevel programming framework.For construction and maintenance costs,a cost model under different cluster lengths is constructed.Employing MATLAB,a study is executed to scrutinize the multifaceted interdependencies among the density of highway traffic,the saturation of intelligent vehicles,and the distribution of roadside RSUs,to establish the most advantageous spacing for RSU installations.This research lays the groundwork for the deployment of sensor networks along highways.In conclusion,the model's accuracy is confirmed by employing the Warshall algorithm and clustering routing methodologies. 展开更多
关键词 RSU placement Bilevel programming framework Coupling theory of traffic flow and information flow Node energy loss model Warshall algorithm Clustering routing methodologies
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Development and Application of an Emergency Skills Training Program for Primary Care Nurses Based on the ADDIE Model in the Context of a Medical Consortium 认领 引用
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作者 Wenping LI Nian LIU +3 位作者 Wulun XIE Yutong ZHENG Danna LIU Songhong XIE 《Medicinal Plant》 2026年第2期45-48,65,共4页
[Objectives]To develop an emergency skills training program for primary care nurses based on the ADDIE(Analysis,Design,Development,Implementation,Evaluation)model and to validate its effectiveness within the context o... [Objectives]To develop an emergency skills training program for primary care nurses based on the ADDIE(Analysis,Design,Development,Implementation,Evaluation)model and to validate its effectiveness within the context of a medical consortium.[Methods]A mixed-methods design was employed to develop the training program,incorporating a cross-sectional survey(n=318),semi-structured interviews(n=15),and a Delphi expert consultation(n=15).Besides,a quasi-experimental study design was adopted.A total of 126 primary care nurses from the medical consortium who met the eligibility criteria were enrolled.The six-month training program was implemented,and changes in emergency competence,self-efficacy,core competence,as well as first-aid knowledge and skills were compared before and after the training.[Results]The developed training program was comprised of five modules encompassing 23 core components.The expert authority coefficient(Cr)was 0.877,and the Kendall's coordination coefficient(W)was 0.362(P<0.001).After the intervention,the nurses'total emergency competence score significantly increased from(90.12±14.85)points to(118.67±11.23)points(t=-18.742,P<0.001).Their self-efficacy score rose from(25.31±5.67)points to(29.84±4.12)points(t=-8.912,P<0.001).The total core competence score improved from(198.45±28.34)points to(235.76±22.15)points(t=-13.565,P<0.001).The pass rate for the first-aid theory assessment increased from 45.24%to 89.68%(χ2=55.632,P<0.001),and the pass rate for the operational skills assessment increased from 38.10%to 85.71%(χ2=61.274,P<0.001).[Conclusions]The training program constructed based on the ADDIE model can systematically improve the emergency competence,self-efficacy,and core competencies of primary care nurses,providing an actionable practical model for implementing standardized emergency training within the medical consortium. 展开更多
关键词 ADDIE(Analysis,Design,Development,Implementation,Evaluation)model Primary case nurses Emergency competence Training program Medical consortium
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Adapting High-Level Language Programming(C Language)Education in the Era of Large Language Models 认领 引用 被引量：1
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作者 Baokai Zu Hongyuan Wang +1 位作者 Hongli Chen Yafang Li 《Journal of Contemporary Educational Research》 2025年第5期264-269,共6页
With the widespread application of large language models(LLMs)in natural language processing and code generation,traditional High-Level Language Programming courses are facing unprecedented challenges and opportunitie... With the widespread application of large language models(LLMs)in natural language processing and code generation,traditional High-Level Language Programming courses are facing unprecedented challenges and opportunities.As a core programming language for computer science majors,C language remains irreplaceable due to its foundational nature and engineering adaptability.This paper,based on the rapid development of large model technologies,proposes a systematic reform design for C language teaching,focusing on teaching objectives,content structure,teaching methods,and evaluation systems.The article suggests a teaching framework centered on“human-computer collaborative programming,”integrating prompt training,AI-assisted debugging,and code generation analysis,aiming to enhance students’problem modeling ability,programming expression skills,and AI collaboration literacy. 展开更多
关键词 Large language models(LLMs) High-level language programming C language Human-computer collaborative programming
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A simulation-based two-stage interval-stochastic programming model for water resources management in Kaidu-Konqi watershed,China 认领 引用 被引量：6
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作者 Yue HUANG Xi CHEN +2 位作者 YongPing LI AnMing BAO YongGang MA 《Journal of Arid Land》 SCIE 2012年第4期390-398,共9页
This study presented a simulation-based two-stage interval-stochastic programming （STIP） model to support water resources management in the Kaidu-Konqi watershed in Northwest China. The modeling system coupled a dis... This study presented a simulation-based two-stage interval-stochastic programming （STIP） model to support water resources management in the Kaidu-Konqi watershed in Northwest China. The modeling system coupled a distributed hydrological model with an interval two-stage stochastic programing （ITSP）. The distributed hydrological model was used for establishing a rainfall-runoff forecast system, while random parameters were pro- vided by the statistical analysis of simulation outcomes water resources management planning in Kaidu-Konqi The developed STIP model was applied to a real case of watershed, where three scenarios with different water re- sources management policies were analyzed. The results indicated that water shortage mainly occurred in agri- culture, ecology and forestry sectors. In comparison, the water demand from municipality, industry and stock- breeding sectors can be satisfied due to their lower consumptions and higher economic values. Different policies for ecological water allocation can result in varied system benefits, and can help to identify desired water allocation plans with a maximum economic benefit and a minimum risk of system disruption under uncertainty. 展开更多
关键词 optimization two-stage stochastic programming uncertainty water resources management hydrological model Kaidu-Konqi watershed Tarim River Basin
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Automatic Algorithm Programming Model Based on the Improved Morgan's Refinement Calculus 认领 引用 被引量：7
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作者 ZUO Zhengkang HU Ying +2 位作者 HUANG Qing WANG Yuan WANG Changjing 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2022年第5期405-414,共10页
The automatic algorithm programming model can increase the dependability and efficiency of algorithm program development,including specification generation,program refinement,and formal verification.However,the existi... The automatic algorithm programming model can increase the dependability and efficiency of algorithm program development,including specification generation,program refinement,and formal verification.However,the existing model has two flaws:incompleteness of program refinement and inadequate automation of formal verification.This paper proposes an automatic algorithm programming model based on the improved Morgan’s refinement calculus.It extends the Morgan’s refinement calculus rules and designs the C++generation system for realizing the complete process of refinement.Meanwhile,the automation tools VCG(Verification Condition Generator)and Isabelle are used to improve the automation of formal verification.An example of a stock’s maximum income demonstrates the effectiveness of the proposed model.Furthermore,the proposed model has some relevance for automatic software generation. 展开更多
关键词 automatic algorithm programming model program refinement VCG Isabelle Morgan’s refinement calculus
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Bi-level programming model for reconstruction of urban branch road network 认领 引用 被引量：8
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作者 史峰 黄恩厚 +1 位作者 陈群 王英姿 《Journal of Central South University》 SCIE EI CAS 2009年第1期172-176,共5页
Considering the decision-making variables of the capacities of branch roads and the optimization targets of lowering the saturation of arterial roads and the reconstruction expense of branch roads, the bi-level progra... Considering the decision-making variables of the capacities of branch roads and the optimization targets of lowering the saturation of arterial roads and the reconstruction expense of branch roads, the bi-level programming model for reconstructing the branch roads was set up. The upper level model was for determining the enlarged capacities of the branch roads, and the lower level model was for calculating the flows of road sections via the user equilibrium traffic assignment method. The genetic algorithm for solving the bi-level model was designed to obtain the reconstruction capacities of the branch roads. The results show that by the bi-level model and its algorithm, the optimum scheme of urban branch roads reconstruction can be gained, which reduces the saturation of arterial roads apparently, and alleviates traffic congestion. In the data analysis the arterial saturation decreases from 1.100 to 0.996, which verifies the micro-circulation transportation's function of urban branch road network. 展开更多
关键词 branch road reconstruction bi-level programming model micro-circulation traffic
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Non-Linear Increase of the Real Contact Area of PMMA Blocks and the Related Contact Model 认领 引用
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作者 Zhijun Luo Kai Wu Shaoze Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2025年第1期261-272,共12页
Many experiments have supported the contact models,such as the GW and MB models,but the majority of previous validations have been performed under light loads,resulting in a linear relationship between normal force an... Many experiments have supported the contact models,such as the GW and MB models,but the majority of previous validations have been performed under light loads,resulting in a linear relationship between normal force and contact area.However,the real contact area fraction should never equal one;there must be a limit smaller than the apparent area,implying that the real contact area cannot increase linearly indefinitely.In this paper,the real contact area between two polymethylmethacrylate(PMMA)blocks under heavy load is measured using the total reflection method,and the contact area is analyzed using the image processing method.The results show that the real contact area increases with normal load linearly in light loads but non-linearly in heavy loads;the number of contact spots increases with load linearly in light loads but also non-linearly in heavy loads,synchronous with the change in the real contact area.The GW,MB,and Zhao,Maietta,and Chang(ZMC)models were used to predict the experiment results,but none of them predicted the non-linear stage.A revised GW model based on the bulk deformation hypothesis performs better in predicting the non-linear stage.The study’s findings can be applied to PMMA or other similar materials,and they can serve as a useful reference for future research on the contact mechanisms of other materials. 展开更多
关键词 Real contact area GW model MB model Total reflection Non-linear increase
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Linear-in-Parameter Models Based on Parsimonious Genetic Programming Algorithm and Its Application to Aero-Engine Start Modeling 认领 引用 被引量：4
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作者 李应红 尉询楷 《Chinese Journal of Aeronautics》 EI CAS 2006年第4期295-303,共9页
A novel Parsimonious Genetic Programming （PGP） algorithm together with a novel aero-engine optimum data-driven dynamic start process model based on PGP is proposed. In application of this method, first, the traditio... A novel Parsimonious Genetic Programming （PGP） algorithm together with a novel aero-engine optimum data-driven dynamic start process model based on PGP is proposed. In application of this method, first, the traditional Genetic Programming（GP） is used to generate the nonlinear input-output models that are represented in a binary tree structure; then, the Orthogonal Least Squares algorithm （OLS） is used to estimate the contribution of the branches of the tree （refer to basic function term that cannot be decomposed anymore according to special rule） to the accuracy of the model, which contributes to eliminate complex redundant subtrees and enhance GP＇s convergence speed; and finally, a simple, reliable and exact linear-in-parameter nonlinear model via GP evolution is obtained. The real aero-engine start process test data simulation and the comparisons with Support Vector Machines （SVM） validate that the proposed method can generate more applicable, interpretable models and achieve comparable, even superior results to SVM. 展开更多
关键词 aerospace propulsion system linear-in-parameter nonlinear model Parsimonious Genetic Programming （PGP） aero-engine dynamic start model
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Tri-level programming model for combined urban traffic signal control and traffic flow guidance 认领 引用 被引量：3
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作者 SUN Zhi-yuan LU Hua-pu QU Wen-cong 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2443-2452,共10页
In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed sign... In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed signal control at intersections, traffic assignment under traffic flow guidance, and dynamic characteristics of urban traffic management, a tri-level programming model is presented. To reflect the impact of intersection delay on traffic assignment, the lower level model is set as a modified user equilibrium model. The middle level model, which contains several definitional constraints for different phase modes, is built for the traffic signal control optimization. To solve the problem of tide lane management, the upper level model is built up based on nonlinear 0-1 integer programming. A heuristic iterative optimization algorithm(HIOA) is set up to solve the tri-level programming model. The lower level model is solved by method of successive averages(MSA), the middle level model is solved by non-dominated sorting genetic algorithm II(NSGA II), and the upper level model is solved by genetic algorithm(GA). A case study is raised to show the efficiency and applicability of the proposed modelling and computing method. 展开更多
关键词 traffic engineering traffic signal control traffic flow guidance tri-level programming model
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Multistage Stochastic Programming Model for the Portfolio Problem of a Property-Liability Insurance Company 认领 引用 被引量：3
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作者 王春峰 杨建林 蒋祥林 《Transactions of Tianjin University》 CAS 2002年第3期203-206,共4页
The current portfolio model for property-liability insurance company is only single period that can not meet the practical demands of portfolio management, and the purpose of this paper is to develop a multiperiod mod... The current portfolio model for property-liability insurance company is only single period that can not meet the practical demands of portfolio management, and the purpose of this paper is to develop a multiperiod model for its portfolio problem. The model is a multistage stochastic programming which considers transaction costs, cash flow between time periods, and the matching of asset and liability; it does not depend on the assumption for normality of return distribution. Additionally, an investment constraint is added. The numerical example manifests that the multiperiod model can more effectively assist the property-liability insurer to determine the optimal composition of insurance and investment portfolio and outperforms the single period one. 展开更多
关键词 property-liability insurance company portfolio management multiperiod model multistage stochastic programming
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Knowledge representation and rule-based solution system for dynamic programming model 认领 引用 被引量：1
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作者 胡祥培 王旭茵 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第2期190-194,共5页
A knowledge representation has been proposed using the state space theory of Artificial Intelligence for Dynamic Programming Model, in which a model can be defined as a six tuple M=(I,G,O,T,D,S). A building block mode... A knowledge representation has been proposed using the state space theory of Artificial Intelligence for Dynamic Programming Model, in which a model can be defined as a six tuple M=(I,G,O,T,D,S). A building block modeling method uses the modules of a six tuple to form a rule based solution model. Moreover, a rule based system has been designed and set up to solve the Dynamic Programming Model. This knowledge based representation can be easily used to express symbolical knowledge and dynamic characteristics for Dynamic Programming Model, and the inference based on the knowledge in the process of solving Dynamic Programming Model can also be conveniently realized in computer. 展开更多
关键词 knowledge representation operations research Dynamic Programming Model intelligent modeling support
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FTCSEM—A FORTRAN-based parallelized 1D CSEM forward and inversion program for arbitrary source-receiver geometry 认领 引用
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作者 Wei-ying Chen Si-xu Han +2 位作者 Wan-ting Song Yu-lian Zhu Zheng Liu 《Applied Geophysics》 SCIE CSCD 2026年第2期693-709,870,共17页
This study introduces FTCSEM,a FORTRAN-based,parallelized one-dimensional controlledsource electromagnetic(CSEM)forward modeling and inversion software capable of accommodating arbitrary source-receiver confi guration... This study introduces FTCSEM,a FORTRAN-based,parallelized one-dimensional controlledsource electromagnetic(CSEM)forward modeling and inversion software capable of accommodating arbitrary source-receiver confi gurations.In comparison to existing one-dimensional CSEM tools,FTCSEM incorporates several signifi cant enhancements:it supports transmitters of diverse shapes,quantities,and spatial locations;permits receivers to be positioned flexibly on the surface,subsurface,or in the atmosphere;facilitates simulations and inversions in both frequency and time domains;integrates an adaptive regularized inversion algorithm with multiple model constraints;and leverages GPU-accelerated parallel computing to attain high computational efficiency.Validation through numerical experiments and field data inversion confirms the program’s accuracy and practical applicability.The findings indicate that FTCSEM performs robustly in complex geoelectric environments,multi-source and multi-receiver arrangements,as well as multi-component joint inversion scenarios,thereby offering a versatile and powerful tool for advancing CSEM research and applications. 展开更多
关键词 CSEM forward modeling regularized inversion parallel computing program
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Calculation of fill foundation deformation based on a modified unsaturated soil constitutive model 认领 引用
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作者 YANG Xiaohui ZHAO Zhizhong +1 位作者 GUO Nan ZHU Yanpeng 《Journal of Mountain Science》 SCIE CSCD 2026年第2期869-889,共21页
Deformations in high fill foundations comprising soil–stone mixtures must be accurately predicted to ensure construction quality and long-term operational safety.However,existing computational and analytical methods ... Deformations in high fill foundations comprising soil–stone mixtures must be accurately predicted to ensure construction quality and long-term operational safety.However,existing computational and analytical methods inadequately capture their complex mechanical behavior.We conducted a series of triaxial tests on unsaturated soil samples collected from a high fill project site in northwestern China under three stress paths.The incremental nonlinear and elastoplastic constitutive models for unsaturated soils were modified,and a calculation method was developed for the vertical and lateral deformations of high fill foundations using the layered summation approach.The results indicate that for soil samples with the same mixing ratio(m)and compaction coefficient(n),the strength of the sample and its tendency to exhibit shear dilation increase with the net confining pressure or matric suction.Additionally,the stress–strain curve of the soil sample gradually changes from the strain-hardening type to the ideal elastoplastic type as the compaction coefficient increases.Moreover,the compaction coefficient is an important factor influencing the magnitude of yield stress and yield suction in soil samples,and the yield points of both are similar in shape to the loadingcollapse(LC)and suction increase(SI)yield lines obtained using the Barcelona model in the net mean stress-generalized shear stress(p-s)plane,respectively.The modified incremental nonlinear instantaneous model simultaneously considers the effects of the compaction coefficient,suction and mixing ratio,and the model parameter can be simplified to the tangential modulus expression in the Duncan-Chang model when the suction is zero.Furthermore,the modified elastoplastic constitutive model,which considers the effects of the net mean stress,suction and partial stress,can be simplified to the elastoplastic constitutive relationship of saturated soil when the suction is zero.The proposed deformation calculation method,based on the layered summation theory,is applicable to both elastic and elastoplastic foundation states,as confirmed through numerical simulations.Our work can be used as a reference for the calculation of foundation deformation in similar mixed material high fill projects. 展开更多
关键词 High fill engineering Unsaturated soil triaxial test Incremental non-linear constitutive model Elastoplastic constitutive model Layered summation method Foundation deformation calculation
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Hybridndiff-UQ:Uncertainty quantification for hybrid neural differentiable modeling 认领 引用
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作者 Deepak Akhare Tengfei Luo Jian-Xun Wang 《Theoretical & Applied Mechanics Letters》 EI CAS CSCD 2026年第2期1-24,共24页
The hybrid neural differentiable models mark a significant advancement in the field of scientific machine learning.These models,integrating numerical representations of known physics into deep neural networks,offer en... The hybrid neural differentiable models mark a significant advancement in the field of scientific machine learning.These models,integrating numerical representations of known physics into deep neural networks,offer enhanced predictive capabilities and show great potential for data-driven modeling of complex physical systems.However,a critical and yet unaddressed challenge lies in the quantification of inherent uncertainties stemming from multiple sources.Addressing this gap,we introduce a novel method,uncertainty quantification for hybrid neural differentiable modeling,for effective and efficient uncertainty propagation and estimation in hybrid neural differentiable models,leveraging the strengths of deep ensemble Bayesian learning and nonlinear transformations.Specifically,our approach effectively discerns and quantifies both aleatoric uncertainties,arising from data noise,and epistemic uncertainties,resulting from model-form discrepancies and data sparsity.This is achieved within a Bayesian model averaging framework,where aleatoric uncertainties are modeled through hybrid neural models.The unscented transformation plays a pivotal role in enabling the flow of these uncertainties through the nonlinear functions within the hybrid model.In contrast,epistemic uncertainties are estimated using an ensemble of stochastic gradient descent trajectories.This approach offers a practical approximation to the posterior distribution of both the network parameters and the physical parameters.Notably,our framework is designed for simplicity in implementation and high scalability,making it suitable for parallel computing environments.The merits of the proposed method have been demonstrated through problems governed by both ordinary and partial differentiable equations. 展开更多
关键词 Differentiable programming Scientific machine learning Grey box modeling Uncertainty quantification Scalable bayesian learning
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Genetic programming-based chaotic time series modeling 认领 引用 被引量：1
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作者 张伟 吴智铭 杨根科 《Journal of Zhejiang University Science》 2004年第11期1432-1439,共8页
This paper proposes a Genetic Programming-Based Modeling (GPM) algorithm on chaotic time series. GP is used here to search for appropriate model structures in function space, and the Particle Swarm Optimization (PSO) ... This paper proposes a Genetic Programming-Based Modeling (GPM) algorithm on chaotic time series. GP is used here to search for appropriate model structures in function space, and the Particle Swarm Optimization (PSO) algorithm is used for Nonlinear Parameter Estimation (NPE) of dynamic model structures. In addition, GPM integrates the results of Nonlinear Time Series Analysis (NTSA) to adjust the parameters and takes them as the criteria of established models. Experiments showed the effectiveness of such improvements on chaotic time series modeling. 展开更多
关键词 Chaotic time series analysis Genetic programming modeling Nonlinear Parameter Estimation (NPE) Particle Swarm Optimization (PSO) Nonlinear system identification
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A Three-section Algorithm of Dynamic Programming Based on Three-stage Decomposition System Model for Grade Transition Trajectory Optimization Problems 认领 引用
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作者 魏宇杰 江永亨 黄德先 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第10期1122-1130,共9页
This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differen... This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differential/algebraic equations(DAEs) always cause great computational burden and system non-linearity usually makes GTTO non-convex bearing multiple optima. Therefore, coupled with the three-stage decomposition model, a three-section algorithm of dynamic programming(TSDP) is proposed based on the general iteration mechanism of iterative programming(IDP) and incorporated with adaptivegrid allocation scheme and heuristic modifications. The algorithm iteratively performs dynamic programming with heuristic modifications under constant calculation loads and adaptively allocates the valued computational resources to the regions that can further improve the optimality under the guidance of local error estimates. TSDP is finally compared with IDP and interior point method(IP) to verify its efficiency of computation. 展开更多
关键词 Gradetransition trajectory optimization Adaptivegrid allocation Heuristic modifications Three-section dynamic programming Three-stage decomposition model
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