检索结果-南通市图书馆

A new intelligent prediction system model-the compound pyramid model

在线全文

学校读者我要写书评

暂无评论

science china(information sciences) 2012年第3期55卷 723-736页

作者： YANG BingRu , QU wu, WANG LiJun & ZHOU Ying school of information engineering, university of science and technology beijing, beijing 100083, china school of information engineering University of Science and Technology Beijing Beijing China

A current development trend in research on intelligent systems is to optimize a general intelligent prediction system into an individuation intelligent prediction system that is applied in specialized fields. Protein structure prediction is a challenging international issue. In this paper, we propose a new intelligent prediction system model, designed as a multi-layer compound pyramid model, for predicting secondary protein structure. The model comprises four independent intelligent interfaces and several knowledge discovery methods. The model penetrates throughout the domain knowledge, with the effective attributes chosen by Causal Cellular Automata. Furthermore, a high pure structure database is constructed for training. On the RS126 dataset, the overall state per-residue accuracy, Q3, reached 83.99%, while on the CB513 dataset, Q3 reached 85.58%. Meanwhile, on the CASP8 sequences, the results are superior to those produced by other methods, such as Psipred, Jpred, APSSP2 and BehairPred. These results confirm that our method has a strong generalization ability, and that it provides a model for the construction of other intelligent systems.

关键词： knowledge discovery intelligent prediction system model compound pyramid model

Optimal Risk Sharing for Maxmin Choquet Expected Utility Model

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第2期40卷 430-444页

作者： De-jian TIAN Shang-ri wu school of Mathematics China University of Mining and TechnologyXuzhou 221116China

This article analyzes the Pareto optimal allocations,agreeable trades and agreeable bets under the maxmin Choquet expected utility(MCEU)*** provide several useful characterizations for Pareto optimal allocations for risk averse *** derive the formulation descriptions for non-existence agreeable trades or agreeable bets for risk neutral *** build some relationships between ex-ante stage and interim stage on agreeable trades or bets when new information arrives.

关键词： maxmin Choquet expected utility model Pareto optimal allocation agreeable trade agreeable bet

Research on Anthropomorphic Obstacle Avoidance Trajectory Planning for Adaptive Driving Scenarios Based on Inverse Reinforcement Learning Theory

在线全文

学校读者我要写书评

暂无评论

engineering 2024年第2期33卷 133-145页

作者： jian wu Yang Yan Yulong Liu Yahui Liu school of Mechanical and Automotive engineering Liaocheng UniversityLiaocheng 252000China 2 school of Vehicle and Mobility Tsinghua UniversityBeijing 100084China

The forward design of trajectory planning strategies requires preset trajectory optimization functions,resulting in poor adaptability of the strategy and an inability to accurately generate obstacle avoidance trajectories that conform to real driver behavior *** addition,owing to the strong time-varying dynamic characteristics of obstacle avoidance scenarios,it is necessary to design numerous trajectory optimization functions and adjust the corresponding ***,an anthropomorphic obstacle-avoidance trajectory planning strategy for adaptive driving scenarios is ***,numerous expert-demonstrated trajectories are extracted from the HighD natural driving ***,a trajectory expectation feature-matching algorithm is proposed that uses maximum entropy inverse reinforcement learning theory to learn the extracted expert-demonstrated trajectories and achieve automatic acquisition of the optimization function of the expert-demonstrated ***,a mapping model is constructed by combining the key driving scenario information that affects vehicle obstacle avoidance with the weight of the optimization function,and an anthropomorphic obstacle avoidance trajectory planning strategy for adaptive driving scenarios is ***,the proposed strategy is verified based on real driving *** results show that the strategy can adjust the weight distribution of the trajectory optimization function in real time according to the“emergency degree”of obstacle avoidance and the state of the ***,this strategy can generate anthropomorphic trajectories that are similar to expert-demonstrated trajectories,effectively improving the adaptability and acceptability of trajectories in driving scenarios.

关键词： Obstacle avoidance trajectory planning Inverse reinforcement theory Anthropomorphic Adaptive driving scenarios

Utility and Application of a Versatile Analytical Method for MMF Calculation in AC Machines

在线全文

学校读者我要写书评

暂无评论

CES Transactions on Electrical Machines and Systems 2024年第1期8卷 22-31页

作者： Ze-Zheng wu Robert Nilssen jian-Xin Shen IEEE the College of Electrical engineering Zhejiang UniversityHangzhou 310027China the Department of Electric Energy Norwegian University of Science and TechnologyTrondheimNorwayand also affiliated with the College of Electrical EngineeringZhejiang UniversityHangzhou 310027China

A versatile analytical method(VAM) for calculating the harmonic components of the magnetomotive force(MMF) generated by diverse armature windings in AC machines has been proposed, and the versatility of this method has been established in early literature. However, its practical applications and significance in advancing the analysis of AC machines need further elaboration. This paper aims to complement VAM by augmenting its theory, offering additional insights into its conclusions, as well as demonstrating its utility in assessing armature windings and its application of calculating torque for permanent magnet synchronous machines(PMSM). This work contributes to advancing the analysis of AC machines and underscores the potential for improved design and performance optimization.

关键词： AC machine Analytical method Harmonic analysis MMF Magnetic field Torque calculation

Analysis of forest backscattering characteristics based on polarization coherence tomography

在线全文

学校读者我要写书评

暂无评论

science china(Technological sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,LI XiaoWen 1,2,CHEN ErXue 3,CHENG jian 4 & CAO ChunXiang 21 Institute of Geo-Spatial information science and technology,university of Electronic science and technology of china,Chengdu 610054,china 2 State Key Laboratory of Remote Sensing science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of sciences and beijing Normal university,beijing 100101,china 3Institute of Forest Resources information Technique of Chinese Academy of Forestry,beijing 100091,china 4 school of Electronic engineering,university of Electronic science and technology of china,Chengdu 610054,china Institute of Geo-Spatial information science and technology University of Electronic Science and Technology of China Chengdu China State Key Laboratory of Remote Sensing science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Institute of Forest Resources information Technique of Chinese Academy of Forestry Beijing China school of Electronic engineering University of Electronic Science and Technology of China Chengdu China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolInSAR)simulation of forest scene and PolInSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POLInSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POLInSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POLInSAR PCT vertical structure function

Level Set interface treatment and its application in Euler method

在线全文

学校读者我要写书评

暂无评论

science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 227-236页

作者： wu KaiTeng1,2,HAO Li3,WANG Cheng4 & ZHANG Li1,2 1 Numerical Simulation Sichuan Higher school Key Laboratory,Neijiang Normal university,Neijiang 641112,china 2 College of Mathematics and information science,Neijiang Normal university,Neijiang 641112,china 3 College of science,beijing university of Civil engineering and Architecture,beijing 100044,china 4 State Key Laboratory of Explosion science and technology,beijing Institute of technology,beijing 100081,china Numerical Simulation Sichuan Higher school Key Laboratory Neijiang Normal University Neijiang China College of Mathematics and information science Neijiang Normal University Neijiang China College of science Beijing University of Civil Engineering and Architecture Beijing China State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing China

Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3D programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method.

关键词： Euler method Level Set method shock-wave action on bubble implosion numerical simulation

Continuous advantage learning for minimum-time trajectory planning of autonomous vehicles

在线全文

学校读者我要写书评

暂无评论

science china(information sciences) 2024年第7期67卷 285-294页

作者： Zhuo LI Weiran wu Jialin WANG Gang WANG jian SUN school of Automation Beijing Institute of Technology beijing Institute of technology Chongqing Innovation Center china Academy of Launch Vehicle technology Intelligent Game and Decision Laboratory

This paper investigates the minimum-time trajectory planning problem of an autonomous vehicle. To deal with unknown and uncertain dynamics of the vehicle, the trajectory planning problem is modeled as a Markov decision process with a continuous action space. To solve it, we propose a continuous advantage learning(CAL) algorithm based on the advantage-value equation, and adopt a stochastic policy in the form of multivariate Gaussian distribution to encourage exploration. A shared actor-critic architecture is designed to simultaneously approximate the stochastic policy and the value function, which greatly reduces the computation burden compared to general actor-critic methods. Moreover, the shared actor-critic is updated with a loss function built as mean square consistency error of the advantage-value equation, and the update step is performed several times at each time step to improve data efficiency. Simulations validate the effectiveness of the proposed CAL algorithm and its better performance than the soft actor-critic algorithm.

关键词： trajectory planning continuous advantage learning stochastic policy shared actor-critic

Theoretical analysis of polarization properties for tilted fiber Bragg gratings

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

science china(information sciences) 2010年第2期53卷 390-397页

作者： XU Ou 1 , LU ShaoHua 2 & jian ShuiSheng 2 1 Faculty of information engineering, Guangdong university of technology, Guangzhou 510006, china 2 Institute of Lightwave technology, beijing Jiaotong university, beijing 100044, china Faculty of information engineering Guangdong University of Technology Guangzhou China Institute of Lightwave technology Beijing Jiaotong University Beijing China

The polarization properties for tilted fiber Bragg gratings (TFBGs) are investigated theoretically based on coupled-mode theory and Mueller matrix method. The expression of wavelength-related polarizationdependent loss (PDL) for TFBGs with different tilt angles is derived and calculated. Simulation results are compared, and the results indicate that the polarization capability of TFBGs with 45° angle is stronger than other TFBGs with smaller angles. The degree of polarization for unpolarized light passing TFBGs is also simulated to further evaluate the polarization properties for various tilt angles. In addition, the relationship between physical parameters of a TFBG and its polarization capability is discussed.

关键词： coupled-mode theory degree of polarization (DOP) Mueller matrix method polarization dependent loss (PDL) tilted fiber Bragg gratings

Preferential adsorption control: Ca-based LDO for regenerating used lubricating oil

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论