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Journal of Ocean University of China 2020年第6期19卷 1283-1291页

作者： AN Zhenfang ZHANG Jin xing lei Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Pilot Qingdao National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266071China

In Recent years,seismic data have been widely used in seismic oceanography for the inversion of oceanic parameters represented by conductivity temperature depth(CTD).Using this technique,researchers can identify the water structure with high horizontal resolution,which compensates for the deficiencies of CTD ***,conventional inversion methods are modeldriven,such as constrained sparse spike inversion(CSSI)and full waveform inversion(FWI),and typically require prior deterministic mapping *** this paper,we propose a novel inversion method based on a convolutional neural network(CNN),which is purely *** solve the problem of multiple solutions,we use stepwise regression to select the optimal attributes and their combination and take two-dimensional images of the selected attributes as input *** prevent vanishing gradients,we use the rectified linear unit(ReLU)function as the activation function of the hidden ***,the Adam and mini-batch algorithms are combined to improve stability and *** inversion results of field data indicate that the proposed method is a robust tool for accurately predicting oceanic parameters.

关键词： oceanic parameter inversion seismic multi-attributes convolutional neural network

Numerical Modeling of the Compression Process of Elastic Open-cell Foams

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Chinese Journal of Aeronautics 2007年第3期20卷 215-222页

作者： ZHANG Jia-lei LU Zi-xing Institute of Solid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100083 China

The random models of open-cell foams that can reflect the actual cell geometrical properties are constructed with the Voronoi technique. The compression process of elastic open-cell foams is simulated with the nonlinear calculation module of finite element analysis program. In order to get the general results applicable to this kind of materials, the dimensionless compressive stress is used and the stress-strain curves of foam models with different geometrical properties are obtained. Then, the influences of open-cell geometrical properties, including the shape of strut cross section, relative density and cell shape irregularity, on the compressive nonlinear mechani- cal performance are analyzed. In addition, the numerical results are compared with the predicted results of cubic staggering model. Nu- merical results indicate that the simulated results reflect the compressive process of foams quite well and the geometrical properties of cell have significant influences on the nonlinear mechanical behavior of foams.

关键词： Voronoi technique open-cell foam nonlinear compressive stress

SIMULATION OF EXTRA LIGHT-THIN COMPONENT DEFORMATION WITH ABNORMAL SHAPE

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 393-397页

作者： Gu Lizhi xing lei College of Mechatronics Engineering and Automation Huaqiao University Quanzhou 362021 China College of Mechanical Engineering Jiamusi University Jiamusi 154007 China

Based on the analyses of the structural feature and the function requirements of newstyle bottle cap, the two fundamental components, the lining washer and the outer body, are abstracted as a plate and a cylinder with thin wall respectively. For simulating the deformation of the lining washer under equiaxial pressure, the modified Lagrangian finite element analysis is applied on the 228 triangular elements. Under assembly pressure, the plastoelastic deformation of both the lining washer and the outer body are studied in terms of Tresca＇s yield criterion and the limitation of the plastic deformation is presented when the two components are assembled into one unit. For the production of this kind of bottle cover, experiments are carried out by carefully measuring the changes of the diameter of lining washer as well as that of the outer body. It is shown that results from the experiments have a good agreement with the theoretical calculation and the maximum value of the allowable pressure has successfully been used in the design of newly developed bottle cap production system.

关键词： Simulation New-style composite bottle cap Lining washer Load Plastic deformation

The Stable Carbon Isotopic Compositions of n-Alkanes in Sediments of the Bohai and North Yellow Seas: Implications for Sources of Sedimentary Organic Matter

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Journal of Ocean University of China 2021年第2期20卷 340-348页

作者： DANG Tianxiang CAO Yunyun xing lei Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Stable carbon isotopic compositions of n-alkanes in surface sediments of the Bohai and North Yellow Seas were investigated to elucidate sources of sedimentary organic matter in these seas. The long-chain n-alkanes in surface sediments are predominantly long-chain C27, C29, and C31 types, with obvious odd carbon predominance. The δ13 C values of long-chain n-C27, n-C29, and n-C31 alkanes are-30.8% ± 0.5‰,-31.9% ± 0.6‰, and-32.1% ± 1.0‰, respectively, within the range of n-alkanes of C3 terrestrial higher plants. This suggests that sedimentary n-alkanes are derived mainly from terrestrial higher plants. Compound-specific carbon isotopic analysis of long-chain n-alkanes indicates that C3 terrestrial higher plants predominate(64%–79%), with angiosperms being the main contributors. The n-alkane δ13 C values indicate that mid-chain n-alkanes in sediments are derived mainly from aquatic emergent macrophytes, with significant petroleum pollution and bacterial degradation sources for short-chain n-alkanes.

关键词： biomarker carbon isotopes n-alkanes Bohai Sea North Yellow Sea

An Optimization Capacity Design Method of Wind/Photovoltaic/Hydrogen Storage Power System Based on PSO-NSGA-II

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Energy Engineering 2023年第4期120卷 1023-1043页

作者： lei xing Yakui Liu Yinchuan University of Energy WangtaibaoYinchuan750100China Qingdao University of Technology Qingdao266520China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an710049China

The optimal allocation of integrated energy systemcapacity based on the heuristic algorithms can reduce economic costs and achieve maximum consumption of renewable energy,which has attracted many ***,the optimization results of heuristic algorithms are usually influenced by the choice of *** solve the above problem,the particle swarm algorithm is introduced to find the optimal hyperparameters of the heuristic ***,an integrated energy system consisting of the photovoltaic,wind turbine,electrolysis cell,hydrogen storage tank,and energy storage is ***,the minimum economic cost,the maximum wind and PV power consumption rate,and the minimum load shortage rate are considered to be the objective ***,a hybrid method combined the particle swarm combined with non-dominated sorting genetic algorithms-II is proposed to solve the optimal allocation *** to the optimal result,the economic cost is 6.3 million RMB,and the load shortage rate is 9.83%.Finally,four comparative experiments are conducted to verify the superiority-seeking ability of the proposed *** comparative results indicate that the proposed method possesses a strongermerit-seeking ability,resulting in a solution satisfaction rate of 87.37%,which is higher than that of the unimproved non-dominated sorting genetic algorithms-II.

关键词： Multi-objective optimization wind/photovoltaic/hydrogen power system particle swarm algorithm non-dominated sorting genetic algorithms-II

A multi-UAV deployment method for border patrolling based on Stackelberg game

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Journal of Systems Engineering and Electronics 2023年第1期34卷 99-116页

作者： lei xing HU Xiaoxuan WANG Guoqiang LUO He School of Management Hefei University of TechnologyHefei 230009China Key Laboratory of Process Optimization&Intelligent Decision-making Ministry of EducationHefei 230009China Engineering Research Center for Intelligent Decision-making&Information Systems Technologies Ministry of EducationHefei 230009China

To strengthen border patrol measures, unmanned aerial vehicles(UAVs) are gradually used in many countries to detect illegal entries on borders. However, how to efficiently deploy limited UAVs to patrol on borders of large areas remains challenging. In this paper, we first model the problem of deploying UAVs for border patrol as a Stackelberg game. Two players are considered in this game: The border patrol agency is the leader,who optimizes the patrol path of UAVs to detect the illegal immigrant. The illegal immigrant is the follower, who selects a certain area of the border to pass through at a certain time after observing the leader’s strategy. Second, a compact linear programming problem is proposed to tackle the exponential growth of the number of leader’s strategies. Third, a method is proposed to reduce the size of the strategy space of the follower. Then, we provide some theoretic results to present the effect of parameters of the model on leader’s utilities. Experimental results demonstrate the positive effect of limited starting and ending areas of UAV’s patrolling conditions and multiple patrolling altitudes on the leader ’s utility, and show that the proposed solution outperforms two conventional patrol strategies and has strong robustness.

关键词： border patrol unmanned aerial vehicle(UAV) Stackelberg game compact linear programming dominated strategy elimination

Influence of Bipartite Qubit Coupling on Geometric Phase

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Communications in Theoretical Physics 2006年第1X期46卷 51-54页

作者： xing lei LIANG Mai-Lin Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tianjin University Tianjin 300072 China

The geometric phase of the bipartite Heisenberg spin-1/2 system with one spin driven by rotating magnetic field is investigated. It is found that in the one-site drive case, the intersubsystem coupling can be equivalent to a static quasi-magnetic field in the parameter space. This perspective has satisfactorily explained the irregular asymptote effect of geometric phase. We discuss the property of the two-site magnetic drive spin system and discover that a stationary state with no geometric phase shift is generated.

关键词： geometric phase Heisenberg bipartite system rotating magnetic field

Estimation of S-wave Velocity for Gas Hydrate Reservoir in the Shenhu Area,North South China Sea

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Journal of Ocean University of China 2018年第5期17卷 1091-1102页

作者： LIU Xueqin xing lei LIU Huaishan Key Laboratory of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology

Estimation of S-wave velocity using logging data has mainly been performed for sandstone, mudstone and oil and gas strata, while its application to hydrate reservoirs has been largely overlooked. In this paper we present petxophysical methods to estimate the S-wave velocity of hydrate reservoirs with the P-wave velocity and the density as constraints. The three models used in this paper are an equivalent model （MBGL）, a three-phase model （TPBE）, and a thermo-elasticity model （TEM）. The MBGL model can effectively describe the internal relationship among the components of the rock, and the estimated P-wave velocities are in good agreement with the measured data （2.8% error）. However, in the TPBE model, the solid, liquid and gas phases axe considered to be independent of each other, and the estimation results are relatively low （46.6% error）. The TEM model is based on the sensitivity of the gas hydrate to temperature and pressure, and the accuracy of the estimation results is also high （3.6% error）. Before the estimation, the occurrence patterns of hydrates in the Shenhu area were examined, and occurrence state one （the hydrate is in solid form in the reservoir） was selected for analysis. By using the known P-wave velocity and density as constraints, a reasonable S-wave velocity value （ranging from 400 to 1100 m s 1 and for a hydrate layer of 1100 m s 1） can be obtained through multiple iterations. These methods and results provide new data and technical support for further research on hydrates and other geological features in the Shenhu area.

关键词： S-wave velocity estimation hydrate reservoir rock physical model

Origins of Terrestrial Organic Matter in Surface Sediments of the East China Sea Shelf

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Journal of Ocean University of China 2017年第5期16卷 793-802页

作者： ZHANG Hailong xing lei ZHAO Meixun Key Laboratory of Marine Chemistry Theory and Technology(Ocean University of China) Ministry of Education/Qingdao Collaborative Innovation Center of Marine Science and TechnologyQingdao 266100P.R.China Institute of Marine Organic Geochemistry Ocean University of ChinaQingdao 266100P.R.China

Terrestrial organic matter(TOM) is an important component of marine sedimentary OM, and revealing the origins and transport mechanisms of TOM to the East China Sea(ECS) is important for understanding regional carbon cycle. A novel approach combining molecular proxies and compound-specific carbon isotopes is used to quantitatively constrain the origins and transport mechanisms of TOM in surface sediments from the ECS shelf. The content of terrestrial biomarkers of(C_(27)+C_(29)+C_(31)) n-alkanes(52 to 580 ng g^(-1)) revealed a seaward decreasing trend, the δ^(13)CTOC values(-20.6‰ to-22.7‰) were more negative near the coast, and the TMBR(terrestrial and marine biomarker ratio) values(0.06 to 0.40) also revealed a seaward decreasing trend. These proxies all indicated more TOM(up to 48%) deposition in the coastal areas. The Alkane Index, the ratio of C_(29)/(C_(29)+C_(31)) n-alkanes indicated a higher proportion of grass vegetation in the coastal area; While the δ13C values of C_(29) n-alkane(-_(29).3‰ to-33.8‰) indicated that terrestrial plant in the sediments of the ECS shelf were mainly derived from C_3 plants. Cluster analysis afforded detailed estimates of different-sourced TOM contributions and transport mechanisms. TOM in the Zhejiang-Fujian coastal area was mostly delivered by the Changjiang River, and characterized by higher %TOM(up to 48%), higher %C_3 plant OM(68%-85%) and higher grass plant OM(56%-61%); TOM in the mid-shelf area was mostly transported by aerosols, and characterized by low %TOM(less than 17%), slightly lower C_3 plant OM(56%-72%) and lower grass plant OM(49%-55%).

关键词： alkanes coastal terrestrial shelf sedimentary mostly aerosols vegetation quantitatively decreasing

MDP-Based Network Selection with Reward Optimization in HetNets

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Chinese Journal of Electronics 2018年第1期27卷 183-190页

作者： CHEN Xin LI Zhuo WANG Kai xing lei School of Computer Science Beijing Information Science and Technology University Beijing Key Laboratory of Internet Culture and Digital Dissemination Research Beijing Information Science and Technology University

We investigate the network selection problem over heterogeneous networks. We formulate the decision making problem as a Markov decision process(MDP).Two Poisson processes are introduced to model user arrival and departure, and the change of the number of user in a specific network is described by Skellam *** apply the Total order preference by similarity to the ideal solution(TOPSIS) method to address the issue of state space explosion in MDP model. To acquire the optimal network selection scheme, the value iteration algorithm is employed to solve the MDP model. We take simulations in Matlab to prove the effectiveness of the proposed scheme. From the experiment results, it is found that our proposed scheme can reduce handover probability by 7.5%and 40.4% at the early stage of connection, compared with the Infinite MDP-based(IMDP) strategy and TOPSISonly strategy. It can also reduce blocking probability by6.1% compared with IMDP, while maintaining desirable throughput for the target user.

关键词： Heterogeneous networks Network selection Markov decision process(MDP) Multiple attributes decision making