检索结果-南通市图书馆

Designing novel adaptive dynamic event-triggered protocols for uncertain multi-agent systems

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第1期67卷 310-311页

作者： bin cheng bin HE College of Electronics and Information Engineering Tongji University Frontiers Science Center for Intelligent Autonomous Systems

Multi-agent systems (MASs) have garnered widespread attention and have been investigated by numerous researchers in recent years, primarily due to their broad applications in industry, transportation, agriculture, and astronomy. While studying the cooperative control of MASs, numerous researchers place emphasis on reducing the frequency of communication among neighboring agents.

关键词： Directed graphs

Cooperative Output Regulation of Heterogeneous Systems over Directed Graphs:A Dynamic Adaptive Event-Triggered Strategy

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2023年第3期36卷 909-921页

作者： SU Hang cheng bin LI Zhongkui State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Department of Control Science and Engineering College of Electronics and Information EngineeringTongji UniversityShanghai 201804China Frontiers Science Center for Intelligent Autonomous Systems Shanghai 201210China

This paper investigates the cooperative output regulation problem of heterogeneous linear multi-agent systems over directed graphs with the constraint of communication *** that there exists an exosystem whose state information is not available to all agents,the authors develop distributed adaptive event-triggered observers for the followers based on relative information between neighboring *** should be pointed out that,two kinds of time-varying gains are introduced to avoid relying on any global information associated with the network,and dynamic triggering conditions are designed to get rid of continuous *** the basis of the designed observers,the authors devise a local controller for each *** with the existing related works,the main contribution of the current paper is that the cooperative output regulation problem for general directed graphs is solved requiring neither global information nor continuous communications.

关键词： Adaptive control consensus cooperative output regulation directed graph event-triggered control multi-agent systems

Scattering for the Radial Schrodinger Equation with Combined Power-type and Choquard-type Nonlinearities

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第4期40卷 1029-1041页

作者： Ying WANG cheng bin XU The Graduate School of China Academy of Engineering Physics Beijing 100088P.R.China School of Mathematics and Statistics Qinghai Normal UniversityXining 810008P.R.China

In this paper,we show the scattering of the radial solution for the nonlinear Schrodinger equation with combined power-type and Choquard-type nonlinearities iut+△u=λ1|u|p1-1u+λ2(Iα*|u|^(p2))|u|p^(2-2)*** the energy space H^(1)(R^(N))forλ_(1)λ_(2)=-*** establish a scattering criterion for radial solution together with Morawetz estimate which implies the scattering *** show that the defocusing perturbation terms does not determine the scattering solution in energy space.

关键词： Schrodinger equation Choquard-type Scattering theory

A new physical model on the capillary phenomenon of granular particles

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2019年第1期40卷 127-138页

作者： Nan ZHANG bin cheng Hexi BAOYIN Department of Aerospace Engineering Tsinghua University

Similar to the capillary phenomenon of liquid, granular particles can move up to a certain height along a vertically vibrating tube. The certain height, which is called the equilibrium height, is related to some parameters, e.g., the inner diameter of the tube, the amplitude, and the vibration frequency. In this paper, a theoretical model is proposed to explain the physical origin of the capillary phenomenon and the effects of the inner diameter of the tube, the amplitude, and the vibration frequency on the equilibrium height. In this model, the volumes of the inflowing and outflowing particles in a vibration period are calculated, which can significantly broaden our understanding in the flow of particles in the bottom of the tube. In order to prove the assumption of this physical model that the particles in the bottom of the tube move in the form of sine, several experiments are conducted. The granular climbing heights at different granular positions and different time stages are measured. The results show that granules move in the form of sine, which almost coincides with the motion of the tube. Moreover, motivated by the sampling on the asteroid regolith based on this mechanism, the sampling efficiencies for various vibration amplitudes and frequencies are discussed based on the new proposed model. It is found that there is an optimum frequency at which sampling is the most effective.

关键词： granular matter vertical vibration nonlinear dynamics theoretical analysis

Numerical analysis of role of melting rate on electroslag remelting continuous directional solidification of a die steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2021年第12期28卷 1617-1624页

作者： Jie Zhang Jing Li cheng-bin Shi State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

The effect of melting rate on the temperature distribution,velocity field,macrosegregation and dendrite arm spacing during electroslag remelting continuous directional solidification process with a mould of 160 mm in diameter was *** mechanism of solute transport and dendrite growth of austenitic hot-work die steel during electroslag remelting process was *** results showed that a lower melting rate contributed to a higher temperature gradient as well as a shallower liquid metal molten *** the increase in the melting rate,the central counterclockwise vortex in the slag and clockwise vortex in the liquid metal molten pool grew,whereas the marginal clockwise vortex in the slag *** increasing melting rate,the macrosegregation of carbon became more serious,whereas the average value of secondary dendrite arm spacing first decreased and then *** secondary dendrite arm spacing reached a minimum value at melting rate of 98 kg/h,which indicated that 98 kg/h was a proper melting rate for electroslag remelting continuous directional solidification process with a mould of 160 mm in diameter.

关键词： Electroslag remelting continuous directional solidification Melting rate Numerical simulation Solidification structure Die steel

Effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on viscosity and structure of slag for pyrometallurgical processing of spent automotive catalysts

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第3期31卷 608-621页

作者： Zhe Wang Qi-long Wei cheng-bin Shi Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was *** results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and ***,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of *** increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the *** slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure

Influence of cerium treatment on inclusion modification and as-cast microstructure of high-strength low-alloy steel

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2022年第10期29卷 1659-1668页

作者： Ru-ming Geng Jing Li cheng-bin Shi State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

The influence of cerium treatment on the inclusion evolution and as-cast microstructure of high-strength low-alloy steel was *** including the inclusions characteristics,element distribution,and the in situ solidification were analyzed by scanning electron microscopy,energy-dispersive spectroscopy,and high-temperature confocal laser scanning microscopy,*** results indicated that,after the addition of Ce,the Al_(2)O_(3) inclusions evolved to form Ce_(2)O_(2)S and CeAlO_(3) inclusions,which exhibited a decrease in size alongside corresponding increase in their number *** equiaxed grain ratio exhibited by the as-cast microstructure increased significantly upon the addition of Ce,while a reduction in the segregation and a corresponding increase in the homogeneity of the carbon distribution within the as-cast microstructure were also *** results of the in situ observation of the solidification suggested that the addition of Ce significantly reduced the solidification temperature range,thus reducing the carbon *** nucleation effect imparted by Al_(2)O_(3),Ce_(2)O_(2)S,and CeAlO_(3) on theδ-Fe formation was discussed in the context of the disregistry theory,which revealed that the formation of a large number of fine Ce_(2)O_(2)S inclusions promotedδ-Fe formation via heterogeneous nucleation.

关键词： Ce treatment Non-metallic inclusion As-cast microstructure In situ observation Disregistry theory

Structural performance assessment of GFRP elastic gridshells by machine learning interpretability methods

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2022年第10期16卷 1249-1266页

作者： Soheila KOOKALANI bin cheng Jose Luis Chavez TORRES Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil Engineering Technical University of LojaLoja 110102Ecuador

The prediction of structural performance plays a significant role in damage assessment of glass fiber reinforcement polymer(GFRP)elastic gridshell *** learning(ML)approaches are implemented in this study,to predict maximum stress and displacement of GFRP elastic gridshell *** ML algorithms,including linear regression(LR),ridge regression(RR),support vector regression(SVR),K-nearest neighbors(KNN),decision tree(DT),random forest(RF),adaptive boosting(AdaBoost),extreme gradient boosting(XGBoost),category boosting(CatBoost),and light gradient boosting machine(LightGBM),are implemented in this *** features of structural performance considered in this study are the maximum stress as f1(x)and the maximum displacement to self-weight ratio as f2(x).A comparative study is conducted and the Catboost model presents the highest prediction ***,interpretable ML approaches,including shapely additive explanations(SHAP),partial dependence plot(PDP),and accumulated local effects(ALE),are applied to explain the *** is employed to describe the importance of each variable to structural performance both locally and *** results of sensitivity analysis(SA),feature importance of the CatBoost model and SHAP approach indicate the same parameters as the most significant variables for f1(x)and f2(x).

关键词： machine learning gridshell structure regression sensitivity analysis interpretability methods

Geochemical analysis of mixed oil in the Ordovician reservoir of the Halahatang Depression,Tarim Basin,China

在线全文

学校读者我要写书评

暂无评论

Chinese Journal Of Geochemistry 2013年第4期32卷 347-356页

作者： cheng bin WANG Tieguan CHANG Xiangchun State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Shandong University of Science and Technology

In this study,12 crude oil samples were collected and analyzed from the Ordovician reservoir in the Halahatang Depression,Tarim Basin,*** the density of oil samples varies considerably,based on saturated hydrocarbon gas chromatographic(GC),saturated and aromatic hydrocarbon gas chromatographic-mass spectrometric(GC/MS) and stable carbon isotopic composition analyses,all the samples are interpreted to represent a single oil population with similar characteristics in a source bed or a source kitchen,organic facies and even in oil charge *** co-existence of a full suite of n-alkanes and acyclic isoprenoids with UCM and 25-norhopanes in the crude oil samples indicates mixing of biodegraded oil with fresher non-biodegraded oil in the Ordovician ***,according to the conversion diagram of double filling ratios for subsurface mixed crude oils,biodegraded/non-biodegraded oil ratios were determined as in the range from 58/42 to 4/*** on oil density and oil mix ratio,the oils can be divided into two groups:Group 1,with specific density>0.88(g/cm3) and oil mix ratio>1,occurring in the north of the Upper Ordovician Lianglitage and Sangtamu Formation pinchout lines,and Group 2,with specific density<0.88(g/cm3) and oil mix ratio<1,occurring in the south of the pinchout ***,Group 2 oils with low densities and being dominated by non-biodegraded oils are better than Group 1 oils with respect to *** is suggested that more attention should be paid to the area in the south of the Upper Ordovician Lianglitage and Sangtamu Formation pinchout lines for further exploration.

关键词：塔里木盆地地球化学分析奥陶系混合油储层中国生物降解油密度变化