Abstract:The 21st century is a century of complexity and networking.People try to analyze and explain various complex phenomena with the help of network theory,and design effective control schemes to optimize and manage complex systems at the same time.In reality,supply chain is such an example.Since most supply chains have a certain network structure,the study of various problems in supply network is closer to the reality from the perspective of network theory.This paper summarizes and analyzes the development of related researches by combing previous results.At the same time,some problems of supply chain network are discussed,which lay a foundation for further research.

Abstract:Cooperative guidance is a kind of guidance method that multiple missiles accomplish attack or defense tasks cooperatively according to a certain control strategy through information sharing and division of work.It is an important direction in the guidance field in recent years and an inevitable development trend for autonomous combat in the future.In order to complete the specific guidance task and achieve better guidance effect,the research and application of cooperative guidance under multiple constraints is particularly important.This paper comprehensively discusses the research progress of the guidance law under the condition of multiple constraints in the scenario of cooperative combat,including the attack time constraint,attack angle constraint,field of view angle constraint,and multi-constraint comprehensive consideration.Finally,the future development trend in the field of cooperative guidance is prospected.

Abstract:With the development of artificial intelligence and communication technology,it has become a key issue to release the communication resources and extend the service life of broadband and hardware.Different from traditional time-based control,the event-triggered control takes samples only when the event trigger condition is satisfied to update the control policy.This paper first analyzes the event-triggered control in both continuous-time and discrete-time systems from aspect of event triggering communication,and discusses the main ideas of self-triggered control,edge-based event-triggered control,dynamic event-triggered control,and asynchronous event-triggered control.The application of event-triggered control is discussed in terms of consistency,optimization,and game.Two common theoretical analysis methods are given for stability demonstration.Besides,two suitable methods are also presented to exclude the Zeno behavior.At last,the paper summarizes the shortcomings of the current event-triggered work and puts forward some directions on future development.

Abstract:This paper investigates a distributed convex optimization with local constraint sets over weight-balanced directed networks,where the global objective function is described as a sum of some agents' local objective functions.To solve this problem in a distributed way,the problem is transformed into a Fenchel dual problem by introducing local conjugate functions.Then,for the Fenchel dual problem,a distributed continuous-time algorithm is proposed based on the singular perturbation system.When the local objective functions are strongly convex and their gradients are Lipschitz continuous,it is shown that the primal and dual optimality can be both achieved by using the tools from convex analysis and Lyapunov stability.Finally,simulation results are given to illustrate the effectiveness of the proposed algorithm.

Abstract:This paper considers the optimization problem of traffic allocation in a connection-less autonomous system.The objective is to enable each node in the network to independently distribute traffic among any given set of next hops in an optimal way.We model the network utility function with non-concave function because of users’ inelastic requirements on data rates in some practical applications,such as video and audio streaming.Therefore,we tackle the problem of optimizing a generalized class of non-concave utility functions.To solve this problem,we first design a sequence of convex relaxations whose solution converges to that of the original problem.Then,we propose a distributed sending rate control algorithm to solve the convex relaxation problems.The approach taken relies on results from real-analysis theory and optimization theory.All computations required by the algorithm are performed independently and locally at each node using local information and minimum information exchange between neighboring nodes.Numerical simulations are performed to evaluate our results.

Abstract:Radar videos are characterized by large data volume,high update frequency and large transmission bandwidth.While the data transmission bandwidth of USV (Unmanned Surface Vehicles) to shore is limited,and the transmission information is various and large in volume.In the use of USV,radar videos are indispensable support for shore-based operators to ensure safe navigation,quick search and accurate confirmation of belligerent objects.However,there is an inevitable contradiction between the shortage of bandwidth resources of shore-USV data intercommunication and the large information transmission demand of radar videos.Based on the principle of radar detection and imaging,this paper presents the digital representation of the radar videos,and realizes the restoration and display of radar video by the shore-based control station through video compression,data transmission and restoration display.The proposed wireless transmission method is applied to a USV control system,and results demonstrate that it is high in video compression ratio,low in processing delay,with complete video restoration and good fault tolerance.

Abstract:To improve the optimization performance of the ant colony optimization algorithm for continuous domains and reduce the correlation among decision variables,a hybrid ant colony optimization algorithm based on MIMIC (Mutual Information Maximization for Input Clustering) algorithm and RPCA (Robust Principal Component Analysis) is designed.Firstly,the ant colony optimization algorithm for continuous domains is introduced.Then,a definition of effective correlation to deal with multivariable correlation is given and a hybrid ant colony optimization algorithm based on MIMIC algorithm and RPCA is proposed.Finally,through solving the standard test functions and comparing the results with that of the ant colony optimization algorithm for continuous domains,the proposed algorithm is proved to have great improvement in optimization ability and convergence,therefore,it is an effective optimization algorithm.

Abstract:During the 12th Five Year Plan period,National High Technology Research and Development Program of China (863 Program),as one of the main drivers of science and technology development,has provided important support for improving China's scientific and technological strength and innovation ability.Acceptance experts play a key role in assessing the level of subject completion and measuring the value of scientific research achievements.The reliability of their scores is directly related to the rationality of 863 program implementation evaluation.Therefore,taking the subject acceptance in a certain field as an example,this paper combines an inverse reinforcement-based model and mathematical statistics methods to systematically analyze the rating bias of technical acceptance experts.Finally,these experts are divided into 8 categories according to their rating performances and corresponding suggestions are given respectively.The results show that the scores are reasonable as a whole,and most experts can give reliable scores;although there are some differences in the rating scales,they are basically in an acceptable range.This study will provide a reference for the review work related to national science and technology plan,and other scientific research management activities,in order to reasonably carry out expert evaluation,refine and standardize review behaviors,improve field expert databases,and select acceptance expert candidates.

Abstract:Three-dimensional (3D) reconstruction technology can be applied in many fields such as 3D CT images in medicine,path planning in robots,and display of relics in archaeological work.The completeness and accuracy of 3D reconstruction are directly related to steps of Structure from Motion (SfM) and Multi-View System (MVS).In this paper,we introduce these two steps in detail.In the reconstruction of sparse point cloud,feature point detection and matching and SfM reconstruction methods are introduced and elaborated.We summarize the researches on feature point detection and matching in recent years,and classify the reconstruction methods of SFM into global and incremental ones,and introduce them in detail.In the dense point cloud reconstruction,the depth map estimation is introduced and elaborated,in which the traditional geometric calculation method,hybrid geometry-and deep learning-based approach,and deep learning based method are summarized.Meanwhile,the evaluation index of 3D reconstruction is introduced.Finally,the image based 3D reconstruction is summarized,and the problems facing the 3D reconstruction and possible future research directions are listed.

Abstract:A novel miniaturized wideband plane omnidirectional antenna with 3.4-7.4 GHz band is designed in this paper.Based on traditional circular monopole planar antenna,the antenna introduces a Wilkinson power divider,a tapered microstrip feeder,and a bottled floor structure.A Wilkinson power divider is introduced at the microstrip feeder to improve the unroundness of pattern,which achieves better omnidirectional radiation;and a metal ground floor of bottle shaped structure is printed on the back of this antenna to achieve good impedance matching effect.The results show that the planar omnidirectional antenna has impedance bandwidth of 4 GHz,the gain at the center frequency of 5.4 GHz is 3.35 dB,the unroundness of radiation pattern at the center frequency of 5.4 GHz is less than 3.50 dB,and the gain at the whole impedance bandwidth is 2.3-3.35 dB.The simulation results are basically consistent with the measured results.

Abstract:In view of the heavy workload of tennis pickup in tennis court,as well as the problems of large size,poor flexibility and low efficiency of the existing tennis picking robots,an intelligent small mobile robot capable of automatic tennis picking based on STM32 was designed.The robot's mechanical structure was presented by constructing its 3D model.The robot adopted the centroid method to obtain target's coordinate information,and realized acts including target search,tennis pick and tennis deposit automatically,under the effective cooperation of its machine vision module,the walking steering gear,the universal wheel,and the double mechanical arms.The experiment results showed that the robot can quickly locate and collect tennis with high precision up to 98%.

Abstract:As an important factor influencing image quality,noise can blur characteristic details and reduce the signal to noise ratio,thus make the denoising critical in image processing.A wavelet frame based Poisson denoising model for color images is proposed in this paper,where the weighted l² is chosen as fidelity term and the l¹ item containing wavelet frame as a regularization item,while the reweighted split Bregman algorithm is employed to solve this model.Numerical experiments are carried out and PSNR indicators are used to assess the denoising effect of the proposed model.Results show that the algorithm is feasible and effective.

Abstract:In order to improve the limitation of the number of delay lines in the existing feedback delay network method and the inability to determine the sub-band reverberation time,this paper introduces a feedback delay network for artificial reverberationbased on the Householder feedback matrix and Butterworth filter bank.The Householder feedback matrix can maximize the echo density,the choice of delay lines number is relatively free.The Butterworth filter bank is convenient for specifying the sub-band reverberation time.In the simulation experiment,the validity of the proposed method wasverified by spectrogram,perceptual evaluation of speech quality,and subjective evaluation.

Abstract:A contour extraction method for urban green spaces along roads was proposed based on the spectrum domain.Remotely sensed images were transformed into the Fourier domain,the spectrum energy was analyzed,and the direction and cut-off frequency corresponding to the contours of green spaces along roads were established.Gabor filters were specifically designed to extract the contours of these green spaces.The central lines on roads were detected by filtering at a low frequency,and the green spaces along the roads were extracted as a buffer of these central lines.The results showed that the filter parameters can be set accurately based on the frequency spectrum analysis of image features,and the contours of urban green spaces along roads can be effectively extracted.

Abstract:As an important parameter of aerosols,mass density affects the complex chemical reactions in the atmosphere,and is closely related to the transport process and spatial distribution of aerosols.In this paper,column mass densities of dust aerosols and dust PM_2.5 aerosols in the Tarim Basin are studied over period of 1980-2018 based on the MERRA-2 data.Generally,the column mass densities of dust aerosols and dust PM_2.5 aerosols over the Tarim Basin show large variations with average values of 0.33 g/m² and 0.086 g/m²,respectively,as well as distinctive annual,monthly and seasonal patterns.The annual average column mass densities of dust aerosols and dust PM_2.5 aerosols in the Tarim Basin vary in ranges of 0.24-0.41 g/m² and 0.06-0.11 g/m²,respectively.As for their seasonal and monthly variations,the column mass densities are large in spring (0.47 g/m²and 0.12 g/m²) and small in winter (0.13 g/m² and 0.04 g/m²),which peak in May with values of 0.57 g/m²and 0.14 g/m²,and lowest in January with values of 0.1 g/m² and 0.03 g/m²,for dust aerosols and dust PM_2.5 aerosols,respectively.

Abstract:With regard to the issue of unreliable multi-hop transmission in power wireless communication networks,this article proposes a retransmission-free multi-hop efficient transmission scheme based on mesh.This solution distributes device nodes between the source node and the receiving node,and designs a retransmission-free protocol,so that all nodes can automatically identify their next state based on the listened/received ACK/NACK information.The proposed method can reduce the average total number of transmissions of each data block effectively with no adding of network signaling,and improve the power wireless communication network in aspects of deep coverage,low latency,and highly reliable service transmission capabilities.Finally,it is proved through theoretical simulations that with the increase of the block error rate,the average total number of transmissions of this scheme has been significantly improved compared with traditional scheme,which effectively reduces the end-to-end average transmission time,thus the proposed scheme has good practical application prospect.