期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到82,380篇文章
< 1 2 … 250 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Bi-level programming model for reconstruction of urban branch road network 认领 引用 被引量：8
1
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
暂未订购 下载PDF
Adaptive path planning for unmanned aerial vehicles based on bi-level programming and variable planning time interval 认领 引用 被引量：7
2
作者 Liu Wei Zheng Zheng Cai Kaiyuan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第3期646-660,共15页
This paper presents an adaptive path planner for unmanned aerial vehicles （UAVs） to adapt a real-time path search procedure to variations and fluctuations of UAVs’ relevant performances, with respect to sensory cap... This paper presents an adaptive path planner for unmanned aerial vehicles （UAVs） to adapt a real-time path search procedure to variations and fluctuations of UAVs’ relevant performances, with respect to sensory capability, maneuverability, and flight velocity limit. On the basis of a novel adaptability-involved problem statement, bi-level programming （BLP） and variable planning step techniques are introduced to model the necessary path planning components and then an adaptive path planner is developed for the purpose of adaptation and optimization. Additionally, both probabilistic-risk-based obstacle avoidance and performance limits are described as path search constraints to guarantee path safety and navigability. A discrete-search-based path planning solution, embedded with four optimization strategies, is especially designed for the planner to efficiently generate optimal flight paths in complex operational spaces, within which different surface-to-air missiles （SAMs） are deployed. Simulation results in challenging and stochastic scenarios firstly demonstrate the effectiveness and efficiency of the proposed planner, and then verify its great adaptability and relative stability when planning optimal paths for a UAV with changing or fluctuating performances. 展开更多
关键词 Adaptive Bi-level programming Motion planning Unmanned aerial vehicles Variable time interval
暂未订购 下载PDF
Bi-Level Programming for the Optimal Nonlinear Distance-Based Transit Fare Structure Incorporating Principal-Agent Game 认领 引用
3
作者 Xin Sun Shuyan Chen Yongfeng Ma 《Journal of Harbin Institute of Technology(New Series)》 CAS 2022年第5期69-77,共9页
The urban transit fare structure and level can largely affect passengers’travel behavior and route choices.The commonly used transit fare policies in the present transit network would lead to the unbalanced transit a... The urban transit fare structure and level can largely affect passengers’travel behavior and route choices.The commonly used transit fare policies in the present transit network would lead to the unbalanced transit assignment and improper transit resources distribution.In order to distribute transit passenger flow evenly and efficiently,this paper introduces a new distance-based fare pattern with Euclidean distance.A bi-level programming model is developed for determining the optimal distance-based fare pattern,with the path-based stochastic transit assignment(STA)problem with elastic demand being proposed at the lower level.The upper-level intends to address a principal-agent game between transport authorities and transit enterprises pursing maximization of social welfare and financial interest,respectively.A genetic algorithm(GA)is implemented to solve the bi-level model,which is verified by a numerical example to illustrate that the proposed nonlinear distance-based fare pattern presents a better financial performance and distribution effect than other fare structures. 展开更多
关键词 bi-level programming model principal-agent game nonlinear distance-based fare path-based stochastic transit assignment
暂未订购 下载PDF
Bi-level programming model and algorithm for optimizing headway of public transit line 认领 引用 被引量：1
4
作者 张健 李文权 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期471-474,共4页
Due to the fact that headway is a key factor to be considered in bus scheduling, this paper proposes a bi-level programming model for optimizing bus headway in public transit lines. In this model, with the interests o... Due to the fact that headway is a key factor to be considered in bus scheduling, this paper proposes a bi-level programming model for optimizing bus headway in public transit lines. In this model, with the interests of bus companies and passengers in mind, the upper-level model＇s objective is to minimize the total cost, which is affected by frequency settings, both in time and economy in the transit system. The lower-level model is a transit assignment model used to describe the assignment of passengers＇ trips to the network based on the optimal bus headway. In order to solve the proposed model, a hybrid genetic algorithm, namely the genetic algorithm and the simulated annealing algorithm （GA-SA）, is designed. Finally, the model and the algorithm are tested against the transit data, by taking some of the bus lines of Changzhou city as an example. Results indicate that the proposed model allows supply and demand to be linked, which is reasonable, and the solving algorithm is effective. 展开更多
关键词 headway bi-level model transit assignment hybrid genetic algorithm
暂未订购 下载PDF
An Alternative Approach for Solving Bi-Level Programming Problems 认领 引用 被引量：1
5
作者 Rashmi Birla Vijay K. Agarwal +1 位作者 Idrees A. Khan Vishnu Narayan Mishra 《American Journal of Operations Research》 2017年第3期239-247,共9页
An algorithm is proposed in this paper for solving two-dimensional bi-level linear programming problems without making a graph. Based on the classification of constraints, algorithm removes all redundant constraints, ... An algorithm is proposed in this paper for solving two-dimensional bi-level linear programming problems without making a graph. Based on the classification of constraints, algorithm removes all redundant constraints, which eliminate the possibility of cycling and the solution of the problem is reached in a finite number of steps. Example to illustrate the method is also included in the paper. 展开更多
关键词 Linear Programming Problem Bi-Level Programming Problem Graph Algorithm
暂未订购 下载PDF
Optimization of the bioconversion of glycerol to ethanol using Escherichia coli by implementing a bi-level programming framework for proposing gene transcription control strategies based on genetic algorithms 认领 引用
6
作者 Carol Milena Barreto-Rodriguez Jessica Paola Ramirez-Angulo +2 位作者 Jorge Mario Gomez-Ramirez Luke Achenie Andres Fernando Gonzalez-Barrios 《Advances in Bioscience and Biotechnology》 CAS 2012年第4期336-343,共8页
In silico approaches for metabolites optimization have been derived from the flood of sequenced and annotated genomes. However, there exist still numerous degrees of freedom in terms of optimization algorithm approach... In silico approaches for metabolites optimization have been derived from the flood of sequenced and annotated genomes. However, there exist still numerous degrees of freedom in terms of optimization algorithm approaches that can be exploited in order to enhance yield of processes which are based on biological reactions. Here, we propose an evolutionary approach aiming to suggest different mutant for augmenting ethanol yield using glycerol as substrate in Escherichia coli. We found that this algorithm, even though is far from providing the global optimum, is able to uncover genes that a global optimizer would be incapable of. By over-expressing accB, eno, dapE, and accA mutants in ethanol production was augmented up to 2 fold compared to its counterpart E. coli BW25113. 展开更多
关键词 Bi-level Optimization Escherichia coli Metabolic Flux Analysis Genetic Algorithm
暂未订购 下载PDF
Quality-guaranteed Dubins Path Planning for USV Based on Mixed-integer Piecewise linear Programming for Addressing the Extended Minimum-time Intercept Problem 认领 引用 被引量：1
7
作者 Xing Zhou Kelin Zhu +3 位作者 Shuang Liu Zhaoqing Li Wenxin Zhang Kang Du 《哈尔滨工程大学学报（英文版）》 CSCD 2026年第1期216-227,共12页
During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive... During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h2/(4√2),where h is the piecewise length. 展开更多
关键词 Minimum-time intercept problem Dubins vehicle Mixed-integer piecewise-linear program Linearization Approximate error trigonometric function USV
暂未订购 下载PDF
An overview of mathematical programming solvers:Theory,development,and recent advances 认领 引用
8
作者 Lei HUANG Fan XIAO +2 位作者 Dongdong GE Wotao YIN Zhe LIANG 《ENGINEERING Management》 CSCD 2026年第1期1-16,共16页
Mathematical programming solvers are software tools designed to solve real‑world problems using mathematical programming algorithms.This survey explores the evolution of optimization technologies,from traditional meth... Mathematical programming solvers are software tools designed to solve real‑world problems using mathematical programming algorithms.This survey explores the evolution of optimization technologies,from traditional methods such as the simplex algorithm and branch‑and‑bound techniques to modern advancements that are facilitated by parallel computing,GPU acceleration,and AI algorithms.We also emphasize the recent emergence of mathematical programming solvers developed by research institutes and companies headquartered in China as major players,who have achieved remarkable success in benchmarks when compared to established solvers.This article provides a comprehensive overview of the theoretical foundations,historical progress,and emerging trends in mathematical programming solvers,offering valuable insights for both researchers and practitioners in the field. 展开更多
关键词 survey mathematical programming solver linear programming mixed‑integer programming nonlinear programming
暂未订购 下载PDF
Reprogramming induced neurons from olfactory ensheathing glial cells: A feasible approach for spinal cord injury repair 认领 引用
9
作者 Javier Sierra María Portela-Lomba +1 位作者 Diana Simón M.Teresa Moreno-Flores 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第1期296-297,共2页
Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disruptin... Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disrupting the neural connections that allow communication between the brain and the rest of the body, which results in varying degrees of motor and sensory impairment. Disconnection in the spinal tracts is an irreversible condition owing to the poor capacity for spontaneous axonal regeneration in the affected neurons. 展开更多
关键词 injury feasible programming
暂未订购 下载PDF
Multi-phase trajectory programming with divert capability for lunar lander powered descent 认领 引用
10
作者 ZHANG Xiaowen WANG Dayi +2 位作者 HUANG Xiangyu LI Ji WANG Tianshu 《中国空间科学技术（中英文）》 CSCD 北大核心 2026年第3期143-156,共14页
It is important for a lunar lander to possess a large divert capability during the final landing phase,as this can enhance the tolerance for flight deviations in the early phase or improve the obstacle avoidance perfo... It is important for a lunar lander to possess a large divert capability during the final landing phase,as this can enhance the tolerance for flight deviations in the early phase or improve the obstacle avoidance performance.Therefore,when designing the powered descent trajectory,sufficient final phase divert capability should be reserved at the minimum propellant cost.To this end,a multi-phase trajectory programming(MPTP)method for powered descent with approaching phase divert capability is proposed.First,the entire powered descent trajectory is divided into the main braking phase and the approaching phase.The main braking phase is responsible for dissipating the majority of the initial velocity.The approaching phase is responsible for safely and precisely flying toward the landing site.It is nominally a vertical descent trajectory and possesses equal divert capability in all horizontal directions.Then,a constant-thrust linear tangent guidance(LTG)accounting for the lunar curvature is designed for the main braking phase.For the approaching phase,a variable-thrust lossless convex programming(LCP)guidance considering the constraints of tilt angle and glide-slope angle is developed.Subsequently,to connect the two phases and further optimize the propellant consumption throughout the entire trajectory,a method for determining the phase switching condition is proposed.The originally difficult-to-solve two-parameter optimization problem is decomposed into two more easily solvable subproblems,which are solved iteratively via a bilevel optimization framework.Finally,the divert capability of the proposed method is verified through numerical simulation.The programmed trajectory is basically consistent with the results of the pseudospectral method,with the difference in propellant consumption being only 0.006%.This method is suitable for the rapid iterative design of nominal trajectories for lunar lander powered descent in engineering applications. 展开更多
关键词 lunar landing powered descent trajectory programming multi-phase divert capability
暂未订购 下载PDF
H∞Optimal Output Regulation of Unknown Linear Systems via an Adaptive Dynamic Programming and Internal Model 认领 引用
11
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
暂未订购 下载PDF
Open-loop control of combustion instabilities in a full-scale annular ramjet combustor using linear genetic programming 认领 引用
12
作者 Jianguo TAN Zheng XU +2 位作者 Yao LIU Dongdong ZHANG Yi HOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第2期20-28,共9页
The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programmi... The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programming(LGP)has been developed for a full-scale annular ramjet combustor.The LGP is used to generate control laws that include multi-frequency forcing.These laws are then transformed into square waves to actuate the solenoid valve,which modulates the kerosene supply for open-loop control.The results show that the duty cycle has little effect on instability amplitude,whereas an increase in frequency leads to a remarked reduction in combustion amplitude.After five generations evolvements,the pressure amplitude is reduced by 40.6% under the optimal control law generated by LGP.Furthermore,the machine learning process is depicted using a proximity map of control law similarity,with the search pathway visualized by the steepest descent.All individuals go forward to the upper left corner of the map with the evolution process,terminating at the optimal individual of the fifth generation. 展开更多
关键词 Annular ramjet combustor Combustion instabilities Linear genetic programming Machine learning Open-loop control
暂未订购 下载PDF
Entry trajectory optimization for cross-domain morphing vehicles by hybrid sequential second-order cone programming 认领 引用
13
作者 Zheng Li Zhenyue Jia +2 位作者 Zheng Fang Hongmiao Zhou Jianqiao Yu 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第4期149-175,共27页
This paper proposes a hybrid sequential second-order cone programming(HSSOCP)method with a three-layer scheme for the entry trajectory optimization of the cross-domain morphing vehicles(CDMVs).By defining the new morp... This paper proposes a hybrid sequential second-order cone programming(HSSOCP)method with a three-layer scheme for the entry trajectory optimization of the cross-domain morphing vehicles(CDMVs).By defining the new morphing rate control variable and using relaxation techniques to relax the bank angle constraint,the SOCP-based entry problem is constructed.A dynamic relaxation penal-ization technique is developed in the first layer to overcome artificial infeasibility and significantly enhance initialization robustness.A novel standard oscillation identification(SOI)method is proposed to precisely identify the iteration oscillations of basic SSOCP in the second layer,which can significantly improve the solution accuracy.A soft-trust-region strategy is applied in the third layer to eliminate oscillations and accelerate convergence.Simulation results of two scenarios demonstrate that the proposed SOI method effectively avoids non-standard oscillation interference versus traditional methods.The morphing aircraft can complete tasks better with a 7.01%and 10.43%reduction in heat load respectively compared to fixed-wing aircraft.The HSSOCP method can maintain accuracy while reducing computation time by 63.47%and 73.86%versus VATSSOCP.Monte Carlo simulations further validate the robustness. 展开更多
关键词 Cross-domain vehicle Morphing vehicle Entry trajectory optimization Sequential second-order cone programming Iteration oscillation Hybrid scheme
暂未订购 下载PDF
Entry trajectory optimization for cross-domain morphing vehicles using oscillation-avoidance-based multistage trust-region sequential convex programming 认领 引用
14
作者 Zheng LI Zheng FANG +1 位作者 Zhenyue JIA Jianqiao YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第4期310-333,共24页
This paper develops an Oscillation-avoidance-based Multistage Trust-region Sequential Convex Programming(OMTSCP)method for the highly nonlinear entry trajectory optimization problem of Cross-Domain Morphing Vehicles(C... This paper develops an Oscillation-avoidance-based Multistage Trust-region Sequential Convex Programming(OMTSCP)method for the highly nonlinear entry trajectory optimization problem of Cross-Domain Morphing Vehicles(CDMVs).The decoupling of states and controls for complex nonlinear dynamics is achieved by defining new control and state variables.A series of sub convex problems is formulated by successive linearization and discretization of the constraints.The proposed Trust-region Sequential Convex Programming(TSCP)scheme consists of three stages:an initial guess generation stage,a basic solution stage,and an optimal solution stage.An approach to penalize the dynamic relaxation is firstly developed to obtain an initial guess with considerable accuracy and significantly improve the robustness of the algorithm by overcoming the drawbacks of potential artificial infeasibility.The oscillation phenomenon of the TSCP method under rectangular trust region is then investigated,and a novel N-shape-based oscillation identification method is proposed to identify the oscillation accurately.Finally,an oscillation-avoidance method based on the sort trust-region is proposed to improve the convergence of the TSCP algorithm.Numerical comparisons of the proposed method and a typical TSCP method,as well as the morphing and fixed-morphing vehicles are provided to demonstrate the effectiveness and efficiency of the proposed method and the performance advantages of the morphing vehicle.The robustness of the method is further verified by Monte Carlo simulation. 展开更多
关键词 Convex optimization Cross-domain vehicle Entry trajectory optimization Morphing vehicle Multistage Oscillation phenomenon Trust-region sequential convex programming
暂未订购 下载PDF
Nutritional programming through early exposure to soybean meal:Effects on growth performance,intestinal health,metabolism,and microbiota of juvenile largemouth bass(Micropterus salmoides) 认领 引用
15
作者 Dujuan Zheng Fernando Y.Yamamoto +2 位作者 Yahong Yao Zhihao Zhou Qiyou Xu 《Animal Nutrition》 SCIE CAS CSCD 2026年第2期545-568,共24页
This study investigated nutritional programming(NP)in largemouth bass(Micropterus salmoides)by examining the long-term effects of early soybean meal(SBM)exposure on growth,immunity,and intestinal health.In Phase 1(fry... This study investigated nutritional programming(NP)in largemouth bass(Micropterus salmoides)by examining the long-term effects of early soybean meal(SBM)exposure on growth,immunity,and intestinal health.In Phase 1(fry stage,28 days),720 fry(28 days post-hatch,initial body weight0.17±0.06 g)were divided into two groups(six replicates per group).They were fed either a fishmeal(FM)-based diet(FM1)or a 15%SBM diet(SBM1).In Phase 2(juvenile stage,56 days),a cross-over feeding trial was conducted,generating four groups(four replicates per group):F1F2,FM1 for phase1 followed by a FM-based diet for phase 2(FM2);F1S2,FM1 followed by a 25%SBM diet(SBM2),S1F2(SBM1 followed by FM2),and S1S2(SBM1 followed by SBM2).Phase 1 SBM feeding(SBM1)impaired fry survival,intestinal relative weight,and villus width(P<0.05),and triggered intestinal inflammation and microbial dysbiosis.Compared to the FM1 group,the SBM 1 group exhibited downregulated expression of key intestinal health-related genes,including the tight junction protein gene claudin-1,the anti-inflammatory factor il-10,and lzm.In contrast,it upregulated the expression of proinflammatory genes,including nf-κb,il-15,and ifn-γ1(P<0.05).In Phase 2,continuous SBM exposure(S1S2 group)impaired growth performance,as evidenced by significantly lower final body weight and a poorer feed conversion ratio(P<0.05),but enhanced hepatic alkaline phosphatase(AKP)and LZM activities(P<0.001).Concurrently,the S1S2 group developed an immunologically tolerant intestinal phenotype,characterized by a significant upregulation(P<0.05)of 1)regulatory T cell(Treg)-related transcription factors,including foxp3 and helios;2)the stat5b;3)immunoregulato ry cyto kines,including tgf-βand il-10;and 4)the immune tolerance-related molecule tnfaip2,without a concomitant increase in the pro-inflammatory il-15.Continuous SBM exposure(S1S2)also improved gut microbiota composition,characterized by increased abundance of Firmicutes and Streptococcus and decreased abundance of Proteobacteria.These changes were accompanied by a significant downregulation of the arachidonic acid metabolic pathway(P<0.05 for all observed changes).In contrast,switching to a fishmeal diet in Phase 2(S1F2 group)rescued growth,increased intestinal villus length and hepatic AKP activity,and alleviated inflammation and apoptosis(P<0.05).These results suggest that NP during the juvenile stage induces physiological adaptations and tolerance to SBM-based diets,highlighting its potential to improve sustainable plant protein use in aquafeeds. 展开更多
关键词 Nutritional programming Soybean meal Intestinal inflammation Metabolomics Microbiota Micropterus salmoides
暂未订购 下载PDF
Thermal performance optimization in CuO-water nanofluid enclosure with sinusoidal heating using deep learning and multi-expression programming 认领 引用
16
作者 Naeem Ullah Aneela Bibi +1 位作者 Yufeng Nie Dianchen Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第5期24-48,共25页
Natural convection in enclosures containing nanofluids has attracted significant attention due to its relevance in thermal management systems.In this context,this study presents a comprehensive numerical investigation... Natural convection in enclosures containing nanofluids has attracted significant attention due to its relevance in thermal management systems.In this context,this study presents a comprehensive numerical investigation of flow and heat transfer in a square cavity saturated with water-based CuO nanofluid having a centrally placed sinusoidal-shaped heated element.All the enclosure walls satisfy the no-slip velocity condition.Thermally,the vertical walls are kept at a cold reference temperature,the lower wall is partially heated at its center,and the remaining portions of the lower and entire upper walls are adiabatic.The internal sinusoidal element is also uniformly heated.The flow dynamics and thermal fields are governed by the two-dimensional steady-state Navier-Stokes and energy equations,solved using the Galerkin finite element method.Additionally,a novel hybrid approach integrating multi-expression programming(MEP)technique with a convolutional neural network bidirectional gated recurrent unit(CNN-BiGRU)deep learning network is also applied to enhance flow and thermal prediction accuracy.This hybrid approach enables precise evaluation of how heater waviness,magnetic field orientation,and nanoparticle dispersion influence flow structure and heat transfer.Results reveal stronger convection at high Rayleigh numbers,magnetic damping at increased Hartmann numbers,and higher temperatures with reduced velocity at greater nanoparticle concentrations.Among the analyzed situations,increasing heater waviness improves heat-transfer performance.Both the MEP and CNN-BiGRU models accurately capture the key features of flow and heat transport trends,indicating that the hybrid approach provides enhanced predictive capability for complex convection-driven nanofluid systems. 展开更多
关键词 Magnetohydrodynamic convection Nanofluid flow simulation Sinusoidal heated source Deep learning Multi-expression programming
暂未订购 下载PDF
Laser-induced in situ reprogramming of magnetic shape memory composites for adaptive devices 认领 引用
17
作者 Qianqian Zhang Rui Li +5 位作者 Yuan Tao Yiyu Chen Yanlei Hu Dong Wu Jiaru Chu Jiawen Li 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2026年第1期767-779,共13页
Programmableeprogrammable magneto-responsive composites(MRCs)are highly desirable for applications in soft robotics,morphable actuators,and biomedical devices due to their capabilities of undergoing reversible,complex... Programmableeprogrammable magneto-responsive composites(MRCs)are highly desirable for applications in soft robotics,morphable actuators,and biomedical devices due to their capabilities of undergoing reversible,complex,untethered,and rapid deformations.However,current MRC-based devices primarily rely on soft matrices,which revert to their original shapes and cease functioning when external magnetic fields are removed.Moreover,their magnetization programming,deformations,and functioning need to alternate between encoding and actuation platforms,limiting the adaptability and efficiency.Here,we present a reprogrammable magnetic shape-memory composite(RM-SMC)integrating a shape-memory polymer(SMP)skeleton with phase-transition magnetic microcapsules.High-intensity laser melts microcapsules for magnetic realignment under programmed fields,while low-intensity laser softens SMP for structural reconfiguration without compromising integrity.This dual-laser strategy facilitates in situ magnetization programming,shape morphing,and function execution within a single material system.Our innovative approach enables unique applications,including omnidirectional multi-degree-of-freedom actuators that can activate light switches,solar trackers that optimize energy capture,and adaptive impellers that modulate fluid pumping.By eliminating platform alternation and enabling shape/function retention post-actuation,the RM-SMC platform overcomes critical limitations in conventional MRCs,establishing a paradigm for multifunctional devices requiring persistent configuration control and field-independent operation. 展开更多
关键词 magneto-responsive composites shape memory polymer in situ programming and deformation omnidirectional multi-degree of freedom actuator adjustable fluid pumping
暂未订购 下载PDF
Genetic programming-driven damage state prediction for slender rectangular reinforced concrete structural walls 认领 引用
18
作者 Nabajit Sarkar Kaustubh Dasgupta 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2026年第2期431-447,共17页
Structures located in high seismic zones often utilize reinforced concrete(RC)frame-wall systems for improved lateral strength and stiffness,whereby the structural walls serve as a critical component of the lateral lo... Structures located in high seismic zones often utilize reinforced concrete(RC)frame-wall systems for improved lateral strength and stiffness,whereby the structural walls serve as a critical component of the lateral load resisting system.To effectively assess the potential vulnerability of structural systems across different levels of seismic demands,it is important to establish clear,quantitative thresholds for specific damage states,especially for the critical structural components within a building system.The currently available damage state definitions for RC structural walls are based on empirical limits and do not provide predictions for damage thresholds based on key design characteristics of a wall.To address this challenge,the present study employs genetic programming(GP),a form of artificial intelligence,to formulate accurate expressions for drift prediction for various damage states,using a dataset of 8,125 analytically studied specimens of RC structural walls.These expressions take into account the effects of various design characteristics,such as wall aspect ratio,axial load ratio,boundary element longitudinal reinforcement ratio,web longitudinal reinforcement ratio,and ratio of boundary element length to wall length in determining deformation limits.The developed prediction models have been evaluated for accuracy and validity using various statistical measures.In addition,the proposed equations have been compared with other available deformation limits in relevant design standards and the available literature to predict experimental results of RC wall components.The findings of these analyses indicate that the developed expressions provide significantly higher accuracy and superior predictions compared to existing empirical damage state definitions. 展开更多
关键词 RC structural wall damage state threshold genetic programming drift level parameterized damage state expression
暂未订购 下载PDF
Insights into Student Perceptions of Error Feedback and Improvement Preferences in Online Programming Education 认领 引用
19
作者 Li Zhang Tianze Wang +1 位作者 Jing Jiang Yufei Zhou 《计算机教育》 2026年第3期176-189,共14页
Online programming platforms are popular in programming education.However,there has been no research investigating students’real opinions and expectations of the error feedback mechanisms,leaving educators without a ... Online programming platforms are popular in programming education.However,there has been no research investigating students’real opinions and expectations of the error feedback mechanisms,leaving educators without a solid data foundation when attempting to improve the error feedback mechanisms.This paper makes a survey of 834 students across various programming courses and investigates student perceptions of error feedback mechanisms on online programming platforms.It explores the effectiveness of existing feedback,student satisfaction,and preferences for potential improvements,focusing on automatic error localization and program repair mechanisms.Results reveal a significant portion of students are dissatisfied with current feedback due to its limited informativeness.Students also express a clear demand for stronger feedback mechanisms,such as error localization and repair hints.Nevertheless,they prefer feedback that subtly guides them toward solutions,rather than providing direct and explicit answers,valuing the opportunity to enhance their debugging skills.The findings suggest a need for balanced,educational-focused feedback mechanisms that aid learning while promoting independent problem-solving. 展开更多
关键词 Error feedback Online programming education Program error localization Automated program repair
暂未订购 下载PDF
Molecular Skeleton Programming of Premediators Opens a New Route to Sulfur Electrochemistry 认领 引用
20
作者 Jinlong Wu Yangyang Wan 《Rare Metals》 SCIE EI CAS CSCD 2026年第7期15-18,共4页
Lithium-sulfur(Li-S)batteries are promising next-generation energy-storage systems because sulfur is abundant,inexpensive,and capable of delivering high theoretical capacity through a multi-electron redox reaction[1,2... Lithium-sulfur(Li-S)batteries are promising next-generation energy-storage systems because sulfur is abundant,inexpensive,and capable of delivering high theoretical capacity through a multi-electron redox reaction[1,2].Nevertheless,their practical development remains limited by the complexity of sulfur electrochemistry[3].During discharge,elemental sulfur is reduced through soluble lithium polysulfide intermediates before forming insoluble Li2S.These intermediates diffuse through the electrolyte,shuttle between electrodes,and trigger parasitic reactions,whereas the conversion from polysulfides to Li2S remains kinetically sluggish.Improving Li-S batteries therefore requires not only suppressing polysulfide migration but also actively regulating sulfur redox kinetics. 展开更多
关键词 premediators li s conversion energy storage systems lithium sulfur batteries sulfur abundance sulfur electrochemistry molecular skeleton programming polysulfide intermediates
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 250 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈