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A cooperative detection game:UAV swarm *** fast intruder

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Journal of Systems Engineering and Electronics 2023年第6期34卷 1565-1575页

作者： XIAO Zhiwen fu Xiaowei School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

This paper studies a special defense game using unmanned aerial vehicle(UAV)swarm against a fast *** fast intruder applies an offensive strategy based on the artificial potential field method and Apollonius circle to scout a certain *** defenders,the UAVs are arranged into three layers:the forward layer,the midfield layer and the back *** co-defense mechanism,including the role derivation method of UAV swarm and a guidance law based on the co-defense front point,is introduced for UAV swarm to co-detect the ***,five formations are designed for comparative analysis when ten UAVs are *** Monte Carlo experiments and ablation experiment,the effectiveness of the proposed co-defense method has been verified.

关键词： cooperative detection game unmanned aerial vehicle(UAV)swarm fast intruder defensive strategy co-defense mechanism.

Incorporating Variation and Quality of the Underlying Effects in Meta-Analysis

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Journal of Systems Science & Complexity 2022年第6期35卷 2381-2397页

作者： fu Jinyu LIN Jinguan School of Mathematics Southeast UniversityNanjing 210096China School of Statistics and Data Science Nanjing Audit UniversityNanjing 211815China

This paper proposes a model to further explore the effects of the quality information and variation of the underlying effects on the summary effect measure in meta-analysis.A shape parameter is used in this model to quantify the asymmetry of the effect sizes of studies that are *** of the proposed model parameters is carried out by the Bayesian MCMC *** of the resultant estimates are examined in the simulations and empirical case with data obtained from a total of 22 meta-analyses taken from three different designs.A conclusion would be drawn that it is advisable to take the proposed model,when quality information becomes available,in particular with a situation where the underlying effects approximately follow a normal ***,however,the quality information is absent,the skew-normal distribution for random effect model should be adopted.

关键词： Bayesian estimation heterogeneity overall effect size quality score skew-normal distribution

Component reallocation and system replacement maintenance based on availability and cost in series systems

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Journal of Systems Engineering and Electronics 2022年第6期33卷 1342-1353页

作者： fu Yuqiang MA Xiaoyang School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Information Management Beijing Information Science&Technology UniversityBeijing 100192China

Component reallocation(CR)is receiving increasing attention in many engineering systems with functionally interchangeable and unbalanced degradation *** paper studies a CR and system replacement maintenance policy of series repairable systems,which undergoes minimal repairs for each emergency failure of components,and considers constant downtime and cost of minimal repair,CR and system *** binary mixed integer nonlinear programming models are respectively established to determine the assignment of CR,and the uptime right before CR and system replacement with the objective of minimizing the system average maintenance cost and maximizing the system ***,we derive the optimal uptime right before system replacement with maximization of the system availability,and then give the relationship between the system availability and the component failure ***,numerical examples show that the CR and system replacement maintenance policy can effectively reduce the system average maintenance cost and improve the system availability,and further give the sensitivity analysis and insights of the CR and system replacement maintenance policy.

关键词： component reallocation(CR) system replacement maintenance cost availability binary mixed integer nonlinear programming minimal repair

Hydrodynamic Performance of A Dual-Floater Integrated System Com-bining Hybrid WECs and Floating Breakwaters

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China Ocean Engineering 2022年第6期36卷 969-979页

作者： fu Lei CHENG Yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The high investment and low return of wave energy converters(WECs)seriously hamper their large-scale commercial *** integration of WECs and floating breakwaters is conducive to enhance the competitiveness of wave energy *** objective of this paper is to investigate the hydrodynamic performance of a WEC-breakwater integrated system combining an upstream oscillating water column(OWC)and a downstream oscillating buoy(OB)via numerical simulations and physical experiments.A nonlinear numerical wave flume using Star-CCM+software is employed to obtain calculated results,where a tiny transverse gap is set between the flume wall and the block surface to simulate a similar two-dimensional(2D)*** corresponding physical experiments are also carried out in a practical wave flume to verified the numerical *** comparison of the isolated and hybrid system shows that the hybrid design leads to the decreased conversion efficiency of each WEC,but improves the transmission performance of the hybrid *** wave resonance between two devices causes the abrupt reduction of OWC efficiency and a positive correlation exists with the OB *** total efficiency of the hybrid system is raised by an optimal opening ratio,a shallow OWC draft and a short spacing *** for the OWC draft,other design parameters have weak effect on the wave attenuation of the hybrid *** paper can help understand hydrodynamics of the hybrid WECs integrated with breakwaters and improve their performances.

关键词： wave energy converters floating breakwater oscillating buoy oscillating water column numerical wave flume physical experiment

Floating Waste Discovery by Request via Object-Centric Learning

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Computers, Materials & Continua 2024年第7期80卷 1407-1424页

作者： Bingfei fu School of Computer Science Fudan UniversityShanghai200438China

Discovering floating wastes,especially bottles on water,is a crucial research problem in environmental ***,real-world applications often face challenges such as interference from irrelevant objects and the high cost associated with data ***,devising algorithms capable of accurately localizing specific objects within a scene in scenarios where annotated data is limited remains a formidable *** solve this problem,this paper proposes an object discovery by request problem setting and a corresponding algorithmic *** proposed problem setting aims to identify specified objects in scenes,and the associated algorithmic framework comprises pseudo data generation and object discovery by request ***-data generation generates images resembling natural scenes through various data augmentation rules,using a small number of object samples and scene *** network structure of object discovery by request utilizes the pre-trained Vision Transformer(ViT)model as the backbone,employs object-centric methods to learn the latent representations of foreground objects,and applies patch-level reconstruction constraints to the *** the validation phase,we use the generated pseudo datasets as training sets and evaluate the performance of our model on the original test *** have proved that our method achieves state-of-the-art performance on Unmanned Aerial Vehicles-Bottle Detection(UAV-BD)dataset and self-constructed dataset Bottle,especially in multi-object scenarios.

关键词： Unsupervised object discovery object-centric learning pseudo data generation real-world object discovery by request

Symmetry theories of Hamiltonian systems with fractional derivatives

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Science China(Physics,Mechanics & Astronomy) 2011年第10期54卷 1847-1853页

作者： ZHOU Sha fu Hao fu JingLi Institute of Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China China Jingye Engineering Corporation Limited Shenzhen Branch Shenzhen 518054 China

The Noether and Lie symmetries as well as the conserved quantities of Hamiltonian system with fractional derivatives are es-tablished. The definitions and criteria for the fractional symmetrical transformations and quasi-symmetrical transformations inthe Noether sense of Hamiltonian system are first discussed. Then, using the invariance of Hamiltonian action under the infini-tesimal transformations with respect to time, generalized coordinates and generalized momentums, the fractional Noethertheorem of the system is obtained. further, the Lie symmetry and conserved quantity of the system are acquired. Two exam-ples are presented to illustrate the application of the results.

关键词： symmetry conserved quantity Hamiltonian system fractional derivative

Effect of geometric parameters and grazing incidence on magnetic polaritons excited in 1D multi-groove gratings

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Science China(Technological Sciences) 2021年第8期64卷 1589-1598页

作者： Su ChengShuai fu CeJi LTCS and Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing100871China

In this paper,effect of geometric parameters and grazing incidence on excitation of magnetic polaritons(MPs)in a 1D multigroove grating with different groove depths made of silver was *** results reveal that when the distance between grooves is sufficiently small,the resonance wavelengths of MPs excited in the grooves of unequal depths exhibit red shift with decrease of the distance,contrary to the case with equal groove *** shift of the MP resonance wavelengths was explained with the LC circuit ***,it was found that the resonance wavelengths of MPs depend linearly on the groove depths except when the difference between the groove depths is *** the grooves have equal depths,a large drop of the absorptance can occur due to the interaction and cancellation of the electric field vectors in the region between the ***,the results show that when a TM wave is at grazing incidence,MPs can be excited simultaneously in the grooves at a blue-shifted wavelength due to reduction of the effective capacitance,resulting in a dramatic enhancement of the ***,the results in this work may provide useful guidance in the design of wavelength-selective absorbers based on MPs.

关键词： multi-groove grating magnetic polaritons absorptance LC circuit model

The Actin Cytoskeleton and Signaling Network during Pollen Tube Tip Growth

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Journal of Integrative Plant Biology 2010年第2期52卷 131-137页

作者： Ying fu State Key Laboratory of Plant Physiology and Biochemistry Department of Plant Sciences College of Biological Sciences ChinaAgricultural University Beijing 100193 China

The organization and dynamics of the actin cytoskeleton play key roles in many aspects of plant cell development. The actin cytoskeleton responds to internal developmental cues and environmental signals and is involved in cell division, subcellular organelle movement, cell polarity and polar cell growth. The tip- growing pollen tubes provide an ideal model system to investigate fundamental mechanisms of underlying polarized cell growth. In this system, most signaling cascades required for tip growth, such as Ca^2＋-, small GTPases- and lipid-mediated signaling have been found to be involved in transmitting signals to a large group of actin-binding proteins. These actin-binding proteins subsequently regulate the structure of the actin network, as well as the rapid turnover of actin filaments （F-actin）, thereby eventually controlling tip growth. The actin cytoskeleton acts as an integrator in which multiple signaling pathways converge, providing a general growth and regulatory mechanism that applies not only for tip growth but also for polarized diffuse growth in plants.

关键词： No English Key Word

Sharp Observability Inequalities for the 1-D Plate Equation with a Potential

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Chinese Annals of Mathematics,Series B 2012年第1期33卷 91-106页

作者： Xiaoyu fu College of Mathematics Sichuan UniversityChengdu 610064China Department of Mathematics Indian Institute of TechnologyBombayMumbai 400076India

This paper deals with the problem of sharp observability inequality for the 1-D plate equation wtt ＋ wxxxx ＋ q（t, x）w = 0 with two types of boundary conditions w = wxx = 0 or w = wx = 0, and q（t, x） being a suitable potential. The author shows that 2 the sharp observability constant is of order exp（C｜｜q｜｜^2/7∞） for ｜｜q｜｜∞〉 1. The main tools to derive the desired observability inequalities are the global Carleman inequalities, based on a new point wise inequality for the fourth order plate operator.

关键词： Observability inequality Plate equation Point-wise estimate Carlemanestimate