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Elite Dung Beetle Optimization Algorithm for Multi-UAV Cooperative Search in Mountainous Environments

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Journal of Bionic Engineering 2024年第4期21卷 1677-1694页

作者： Xiaoyong zhang Wei yue The College of Marine Electrical Engineering Dalian Maritime UniversityDalian116026China

This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental ***,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV ***,the task region is decomposed into several high-value sub-regions by using data clustering *** on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search ***,the Elite Dung Beetle Optimization Algorithm(EDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be ***,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path *** effectiveness and superiority of the proposed schemes are verified by the simulation.

关键词： Mountainous environment Multi-UAV cooperative search Environment information consistency Elite dung beetle optimization algorithm(EDBOA) Path planning

Product Form Solution of a Queuing-Inventory System with Lost Sales and Server Vacation

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Journal of Systems Science & Complexity 2024年第2期37卷 729-758页

作者： yue Dequan zhang Yuying XU Xiuli yue Wuyi School of Science Yanshan UniversityQinhuangdao 066004China School of Economics and Management Yanshan UniversityQinhuangdao 066004China The Kyoto College of Graduate Studies for Informatics Kyoto City 606-8225Japan

In this study,the authors consider an M/M/1 queuing system with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead time and the vacation time follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the optimal policy,and the optimal cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy

Target parameter estimation for OTFS-integrated radar and communications based on sparse reconstruction preprocessing

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 742-754页

作者： Zhenkai zhang Xiaoke SHANG yue XIAO Ocean College Jiangsu University of Science and TechnologyZhenjiang 212003China

Orthogonal time-frequency space(OTFS)is a new modulation technique proposed in recent years for high Doppler wireless *** solve the parameter estimation problem of the OTFS-integrated radar and communications system,we propose a parameter estimation method based on sparse reconstruction preprocessing to reduce the computational effort of the traditional weighted subspace fitting(WSF)***,an OTFS-integrated echo signal model is ***,the echo signal is transformed to the time domain to separate the target angle from the range,and the range and angle of the detected target are coarsely estimated by using the sparse reconstruction ***,the WSF algorithm is used to refine the search with the coarse estimate at the center to obtain an accurate *** simulations demonstrate the effectiveness and superiority of the proposed parameterestimation algorithm.

关键词： Integrated radar and communications system Orthogonal time-frequency space Target parameter estimation Sparse reconstruction Weighted subspace fitting

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 13-23页

作者： yue Yang Ze Fu Qi zhang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science&TechnologyNanjing 210094China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresCollege of Engineering and Applied SciencesKey Laboratory of Intelligent Optical Sensing and Manipulation(Ministry of Education)Jiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

Oily wastewater from ocean oil spills endangers marine ecosystems and human health. Therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bottom-layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bottom “bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. Therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 W/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. This work provides a green and cost-effective path for the separation of oil-water mixtures.

关键词： Oily wastewater Carbonized wood Salinity gradient Electricity generation Solar irradiation

Compositional evolution for mixed aerosols containing gluconic acid and typical nitrate and the effect of multiply factors on hygroscopicity

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Journal of Environmental Sciences 2024年第5期139卷 206-216页

作者： yue Zhu Shufeng Pang Yunhong zhang School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China

The aging process of atmospheric aerosols usually leads to a mixture of inorganic salts and organic compounds of anthropogenic *** organic compounds,polyhydroxy organic acids are important components,however,the study on composition and hygroscopic properties of the mixture containing inorganics and polyhydroxy organic acids is *** this study,gluconic acid,the proxy of polyhydroxy organic acids,is mixed with the representative nitrate(Mg(NO_(3))_(2),Ca(NO_(3))_(2))to form ***-FTIR and optical microscopy are employed to study the component changes and hygroscopicity as a function of relative *** relative humidity fluctuates,the FTIR-ATR spectra display that the internal mixed gluconic acid(CH_(2)(CH)_(4)(OH)_(5)COOH)and nitrate can react to release acidic gases,forming relevant gluconate and further affecting the *** specific presentation is particles cannot be recovered to their original size after the dehydration-hydration process and there will be some disparities in GF for mixed *** the gluconic acid-Ca(NO_(3))_(2)/Mg(NO_(3))_(2)mixtures with molar ratios of 1:1,higher degree of reaction resulting in the production of large amounts of gluconate should be responsible to the lower hygroscopicity compared to ZSR *** 1:2 gluconic acid-nitrate mixed systems(with higher nitrate content),the hygroscopicity of mixtures are higher than the ZSR prediction.A possible reason could be‘salt-promoting effect’on the organic fractions of the surplus inorganic salt in the *** data can improve the chemical composition list evaluation,in turn hygroscopic properties and phase state of atmospheric aerosol,and then the climate effect.

关键词： Hygroscopicity Gluconic acid Reaction ZSR simulation Size growth factors

HetNets Under Decoupled Uplink and Downlink Access with UE Random Discontinuous Transmission: Local Delay and Energy Efficiency

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China Communications 2024年第3期21卷 205-216页

作者： zhang yue Zheng Fuchun Luo Jingjing School of Electronic and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

Due to the limited uplink capability in heterogeneousnetworks (HetNets), the decoupled uplinkand downlink access (DUDA) mode has recently beenproposed to improve the uplink performance. In thispaper, the random discontinuous transmission (DTX)at user equipment (UE) is adopted to reduce the interferencecorrelation across different time slots. By utilizingstochastic geometry, we analytically derive themean local delay and energy efficiency (EE) of an uplinkHetNet with UE random DTX scheme under theDUDA mode. These expressions are further approximatedas closed forms under reasonable *** results reveal that under the DUDA mode, there isan optimal EE with respect to mute probability underthe finite local delay constraint. In addition, with thesame finite mean local delay as under the coupled uplinkand downlink access (CUDA) mode, the HetNetsunder the DUDA mode can achieve a higher EE witha lower mute probability.

关键词： decoupled uplink and downlink access(DUDA) heterogeneous networks(HetNets) random discontinuous transmission(DTX) stochastic geometry

Interface structure of α-Mg/14H-LPSO:First-principles prediction and experimental study

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Journal of Rare Earths 2024年第9期42卷 1792-1799,I0006页

作者： Yuan Shi Xiaohua zhang Hongyan yue Chao Li School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China

The interfacial structure of the α-Mg/14H-LPSO phase in rare earth-including magnesium alloy was investigated via high-angle annular dark-field scanning transmission electron microscopy(HAADFSTEM) imaging and first-principles calculations of density-functional *** possible interfacial models were constructed according to the different terminations of the LPSO phase,and the corresponding interfacial energies were calculated,from which the four most stable structures(Terl-MgY-hollow,Ter2-Zn-hollow,Ter3-MgYII-hollow and Ter4-Mg-bridge) were *** interfacial phase diagrams related to the Y chemical potentials were obtained from the calculations,and the most stable interfacial structure was ***-MgY-hollow and Ter2-Zn-hollow have the lowest interfacial energies in the range of-0.7 eV <Δμγ<-0.6 eV,where fluctuating change of state is the minimized and the interface is the most *** separation work of the two models was calculated to predict the bonding strength of the structures at both ends of the *** calculation results show that the maximum interfacial separation work is 1.45 J/m~2 for the interface model of α-Mg and 14H-LPSO phase structure with Ter2-Zn-hollow termination.

关键词： Rare earths Magnesium alloy HAADF-STEM LPSO First-principles Interface

A novel three-inflection-point sliding mode control framework for forward-tilting morphing aerospace vehicle with performance constraints and actuator faults

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Chinese Journal of Aeronautics 2024年第8期37卷 293-310页

作者： Xinkai LI Lei DOU Hongli zhang yue MENG School of Electrical Engineering Xinjiang UniversityUrumqi 830047China

A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator *** accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is *** convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is *** global asymptotic stability of the system is demonstrated using a strict mathematical *** effectiveness and superiority of the proposed control scheme are proven by simulation experiments.

关键词： Morphing aerospace vehicle Actuator faults Immersion and invariance Three-inflection-point sliding mode control Prescribed performance control

Domain Engineering the Flexoelectric Response of BaTiO3-SrTiO3 Binary Films: A Phase Field Study

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ACTA MECHANICA SOLIDA SINICA 2024年第4期37卷 590-597页

作者： Tao, Junyu zhang, Fan zhang, Jianyuan Chen, Weijin Zheng, yue Sun Yat Sen Univ Sch Mat Shenzhen Campus Shenzhen 518107 Peoples R China Sun Yat Sen Univ Sch Phys Guangdong Prov Key Lab Magnetoelectr Phys & Device Guangzhou 510275 Peoples R China Sun Yat Sen Univ Sch Phys State Key Lab Optoelect Mat & Technol Guangzhou 510275 Peoples R China Sun Yat Sen Univ Ctr Phys Mech & Biophys Sch Phys Guangzhou 510275 Peoples R China Southern Marine Sci & Engn Guangdong Lab Zhuhai Zhuhai 519082 Peoples R China

The flexoelectric effect describes the interplay between material polarization and strain gradient. While much research has focused on control strategies for flexoelectricity, the impact of ferroelectric domain structure on the flexoelectric effect remains elusive. Through phase field simulations, we conduct a comparative study on the flexoelectric response of two types of BaTiO3-SrTiO3 binary films: BaTiO3-SrTiO3 multilayers and (Ba,Sr)TiO3 solid solutions. Our findings reveal that the flexoelectric response of these two systems, at the same Ba/Sr ratio, differs not only in magnitude but also in other aspects like temperature dependence, linearity, and hysteresis, due to their different ferroelectric domain structures and evolution dynamics. Our study deepens our current understanding of flexoelectricity in ferroelectrics and suggests "domain engineering" as a potential way to tailor this effect.

关键词： Ferroelectric Flexoelectricity Multilayers Solid solution Phase field POLARIZATION