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A constraint Adaptive Multi-Tasking Differential Evolution Algorithm:Designed for Dispatch of Integrated Energy System in Coal Mine

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Tsinghua Science and Technology 2024年第2期29卷 368-385页

作者： Canyun Dai Xiaoyan Sun Hejuan Hu Yong Zhang Dunwei Gong School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China School of Information Science and Technology Qingdao University of Science and TechnologyQingdao 266061China

The dispatch of integrated energy systems in coal mines(IES-CM)with mine-associated supplies is vital for efficient energy utilization and carbon emissions ***,IES-CM dispatch is highly challenging due to its feature as multi-objective and strong *** constrained multi-objective evolutionary algorithms often fall into locally feasible domains with poorly distributed Pareto front,which greatly deteriorates dispatch *** tackle this problem,we transform the traditional dispatch model of IES-CM into two tasks:the main task with all constraints and the helper task with constraint *** we propose a constraint adaptive multi-tasking differential evolution algorithm(CA-MTDE)to optimize these two tasks *** helper task with constraint adaptive is developed to obtain infeasible solutions near the feasible *** purpose of this infeasible solution is to transfer guiding knowledge to help the main task move away from local ***,a dynamic dual-learning strategy using DE/current-to-rand/1 and DE/current-to-best/1 is developed to maintain task diversity and ***,we comprehensively evaluate the performance of CA-MTDE by applying it to a coal mine in Shanxi Province,considering two IES-CM *** demonstrate the feasibility of CA-MTDE and its ability to generate a Pareto front with exceptional convergence,diversity,and distribution.

关键词： dispatch integrated energy system coal mine evolutionary multi-tasking constraint differential evolution

Finite-time composite guidance law with input constraint and dynamics compensation

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Chinese Journal of Aeronautics 2020年第2期33卷 664-671页

作者： Meijun DUAN Di ZHOU School of Astronautics Harbin Institute of TechnologyHarbin 150001China

Guidance laws are proposed for a near space interceptor with on-off type thrust as *** target-interceptor engagement kinematics is integrated with the first-order dynamics of thruster to design guidance *** bang-bang type guidance law with linear sliding mode is proposed to deal with thruster dynamics,and the sufficient condition for finite time convergence is rigorously proved based on the finite-time convergence *** to the sufficient condition,a sliding mode guidance law with hysteresis-band switching is introduced to reduce the switching frequency of *** two guidance laws are combined into a composite guidance law to improve the guidance *** results show that the line-of-sight angular rate can converge to a neighborhood of the equilibrium point before the final time of the guidance process,and the composite guidance law has better performance than typical guidance laws.

关键词： Dynamics Finite-time convergence Guidance Hysteresis-band switching Near space interceptor Output constraint

Single color image super-resolution using sparse representation and color constraint

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Journal of Systems Engineering and Electronics 2020年第2期31卷 266-271页

作者： XU Zhigang MA Qiang YUAN Feixiang School of Computer and Communication Lanzhou University of TechnologyLanzhou 730050China

Color image super-resolution reconstruction based on the sparse representation model usually adopts the regularization norm(e.g.,L1 or L2).These methods have limited ability to keep image texture detail to some extent and are easy to cause the problem of blurring details and color artifacts in color reconstructed *** paper presents a color super-resolution reconstruction method combining the L2/3 sparse regularization model with color channel *** method converts the low-resolution color image from RGB to *** L2/3 sparse regularization model is designed to reconstruct the brightness channel of the input low-resolution color *** the color channel-constraint method is adopted to remove artifacts of the reconstructed highresolution *** method not only ensures the reconstruction quality of the color image details,but also improves the removal ability of color *** experimental results on natural images validate that our method has improved both subjective and objective evaluation.

关键词： color image sparse representation super-resolution L2/3 regularization norm color channel constraint

On the Expressive Power of Logics on constraint Databases with Complex Objects

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Journal of Computer Science & Technology 2019年第4期34卷 795-817页

作者： Hong-Cheu Liu Jixue Liu School of Information Technology and Mathematical Sciences University of South AustraliaAdelaide 5095Australia

We extend the constraint data model to allow complex objects and study the expressive power of various query languages over this sort of constraint *** tools we use come in the form of collapse results which are well established in the context of first-order *** show that the natural-active collapse with a condition and the activegeneric collapse carry over to the second-order logic for structures with o-minimality property and any signature in the complex value *** expressiveness results for more powerful logics including monadic second-order logic,monadic second-order logic with fix-point operators,and fragments of second-order logic are investigated in the *** discuss the data complexity for second-order logics over constraint *** main results are that the complexity upper bounds for three theories,MSO+(LIN),MSO+(POLY),and Inflationary DATALOGact^cv(SC,M)without powerset operator are∪iΣi^NC1,NCH=∪iΣi^NC,and AC^0/poly,*** also consider the problem of query closure property in the context of embedded finite models and constraint databases with complex objects and the issue of how to determine safe constraint queries.

关键词： constraint database monadic second-order logic natural-active collapse Ramsey property o-minimality structure

Regularized inversion for coseismic slip distribution with active constraint balancing

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Journal of Central South University 2017年第12期24卷 2961-2968页

作者： TONG Xiao-zhong XIE Wei GAO Da-wei School of Geosciences and Info-physics Central South University School of Earth and Ocean Sciences University of Victoria

Estimating the spatial distribution of coseismic slip is an ill-posed inverse problem, and solutions may be extremely oscillatory due to measurement errors without any constraints on the coseismic slip distribution. In order to obtain stable solution for coseismic slip inversion, regularization method with smoothness-constrained was imposed. Trade-off parameter in regularized inversion, which balances the minimization of the data misfit and model roughness, should be a critical procedure to achieve both resolution and stability. Then, the active constraint balancing approach is adopted, in which the trade-off parameter is regarded as a spatial variable at each model parameter and automatically determined via the model resolution matrix and the spread function. Numerical experiments for a synthetical model indicate that regularized inversion using active constraint balancing approach can provides stable inversion results and have low sensitivity to the knowledge of the exact character of the Gaussian noise. Regularized inversion combined with active constraint balancing approach is conducted on the 2005 Nias earthquake. The released moment based on the estimated coseismic slip distribution is 9.91×1021 N·m, which is equivalent to a moment magnitude of 8.6 and almost identical to the value determined by USGS. The inversion results for synthetic coseismic uniform-slip model and the 2005 earthquake show that smoothness-constrained regularized inversion method combined with active constraint balancing approach is effective, and can be reasonable to reconstruct coseismic slip distribution on fault.

关键词： coseismic slip inversion trade-off parameter active constraint balancing model resolution matrix spread function

An Experimental Study on constraint Cooling Process of Hot-rolled CoilS

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Journal of Materials Science & Technology 2003年第z1期19卷 220-222页

作者： Lijuan WANG Chunli ZHANG State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China Shanghai Baosteel Group Corporation Shanghai 201900 China

In order to master mechanical property, surface quality and microstructure of constraint cooling (CC) coils undervarious water cooling parameters, more than 100 coils cooling experiments were done with real production process,of which is designed a cooling experimental instrument in the end. The experiments show that high initial coolingtemperature, discontinuous cooling style, and long cooling time can improve mechanical property of cooling coilsand shorten cooling time. The CC coils experiments cover the different steel grades, so that CC process effects onhot-rolled coils may be predicted and controlled actively.

关键词： constraint cooling, Hot-rolled coils, Experiment

A constraint of Black Hole Mass and the Inner Edge Radius of Relativistic Accretion Disc

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Chinese Physics Letters 2011年第3期28卷 244-247页

作者： HE Liang HUANG Chang-Yin WANG Ding-Xiong School of Physics Huazhong University of Science and TechnologyWuhan 430074

A constraint to black hole(BH)accretion has previously been derived for the inner edge fixed at the innermost stable circular orbit(ISCO)and the innermost bound circular orbit(IBCO).This constraint is referred to as the mass-radius(MR)relation in this study,and the validity of the MR relation is discussed for different *** is shown that the product of the BH mass and the inner edge radius decreases monotonically in the accretion process for the inner edge located between IBCO and *** addition,we discuss the validity of the MR relation by considering the magnetic coupling(MC)effects of a Kerr BH with its surrounding *** theoretically the product of the BH mass and the radius of ISCO increases(decreases)with time for a BH spin greater(less)than some critical value in the MC process,this relation is approximately valid for an Eddington accretion rate persisting for a rather long time,such as more than 10^(6)***,we discuss the possible application of the MR relation to astrophysics.

关键词： radius constraint Radius

Variation of Out-of-Plane constraint and Its Effects on Fracture

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上海交通大学学报 2004年第z2期38卷 212-216页

作者： Fei Xu Yulong Li Wanlin Guo Department of Mechanical Engineering Tokyo University of Science Noda2788510 Japan School of Aeronautics Northwestern Polytechnical University Xi''an710072 P. R. China School of Aeronautics Northwestern Polytechnical University Xi''an710072 P. R. China School of Aeronautics and Astronauts Nanjing University of Aeronautics and AstronautsNaniing210016 P.R.China

The limitations of using one-parameter to describe the crack-tip fields have prompted investigators to consider better descriptions of the crack tip fields. The two-parameter descriptions, such as J-Q theory, have been an important development in this field. But under the consideration of plane strain and three-dimensional problem, the effects of the out-of-plane stress can not be neglected In this paper, effects of the in-plane constraint as well as the out-of-plane constraint are studied by aid of the finite element method on the plane strain condition. It is obvious that both the in-plane constraint (Q factor) and the out-of-plane constraint (Tz = σzz/(σxx + σyy) ) affect the crack tip *** important features of the out-of-plane constraint are described out based on the simulation results. At the end of this paper, a three-parameter formulation is proposed, in which both the in-plane constraint and the out-of-plane constraint are considered. Comparing with the results of the FEM numerical simulation, the three-parameter description can provide a better prediction near the crack tip.

关键词： in-plane constraint out-of-plane constraint three-parameter formulation crack tip field elastic-plastic

Effect of constraint on crack propagation behavior in BGA soldered joints

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Transactions of Nonferrous Metals Society of China 2001年第6期11卷 895-899页

作者：王莉王国忠方洪渊钱乙余 Chinese Acad Sci DaimlerChrysler SIM Technol Co Ltd Shanghai 200050 Peoples R China Harbin Inst Technol Natl Key Lab Adv Welding Prod Technol Harbin 150001 Peoples R China

The effects of stress triaxiality on crack propagation behavior in the BGA soldered joint were analyzed using FEM method. The computation results verified that stress triaxiality factor has an important effect on crack growth behavior. Crack growth rate increased with increasing stress triaxiality at the near tip region, which is caused by increasing crack lengths or decreasing solder joint heights. Solder joint deformation is subjected to constraint effect provided by its surrounding rigid ceramic substrate, the constraint can be scaled by stress triaxiality near crack tip region. Therefore, it can be concluded that crack growth rate increased when the constraint effect increases.

关键词： constraint crack behavior joints