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Equipment damage measurement method of wartime based on FCE-PCA-RF

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Journal of Systems engineering and Electronics 2024年第3期35卷 707-719页

作者： LI Mingyu GAO Lu XU Hongwei LI Kai HUANG Yisong shijiazhuang campus of army engineering university Shijiazhuang 050003China shijiazhuang campus of army Infantry Academy Shijiazhuang 050227China

As the“engine”of equipment continuous operation and repeated operation, equipment maintenance support plays a more prominent role in the confrontation of symmetrical combat systems. As the basis and guide for the planning and implementation of equipment maintenance tasks, the equipment damage measurement is an important guarantee for the effective implementation of maintenance support. Firstly,this article comprehensively analyses the influence factors to damage measurement from the enemy’s attributes, our attributes and the battlefield environment starting from the basic problem of wartime equipment damage measurement. Secondly, this article determines the key factors based on fuzzy comprehensive evaluation(FCE) and performed principal component analysis (PCA) on the key factors. Finally, the principal components representing more than 85%of the data features are taken as the input and the equipment damage quantity is taken as the output. The data are trained and tested by artificial neural network (ANN) and random forest (RF). In a word, FCE-PCA-RF can be used as a reference for the research of equipment damage estimation in wartime.

关键词： wartime equipment damage fuzzy comprehensive evaluation(FCE) principal component analysis(PCA) artificial neural network(ANN) random forest(RF)

Enhancing Dense Small Object Detection in UAV Images Based on Hybrid Transformer

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Computers, Materials & Continua 2024年第3期78卷 3993-4013页

作者： Changfeng Feng Chunping Wang Dongdong Zhang Renke Kou Qiang Fu shijiazhuang campus People Liberation Army Engineering UniversityShijiazhuang050003China School of Information and Intelligent engineering Sanya UniversitySanya572000China

Transformer-based models have facilitated significant advances in object ***,their extensive computational consumption and suboptimal detection of dense small objects curtail their applicability in unmanned aerial vehicle(UAV)*** these limitations,we propose a hybrid transformer-based detector,H-DETR,and enhance it for dense small objects,leading to an accurate and efficient ***,we introduce a hybrid transformer encoder,which integrates a convolutional neural network-based cross-scale fusion module with the original encoder to handle multi-scale feature sequences more ***,we propose two novel strategies to enhance detection performance without incurring additional inference *** filter is designed to cope with the dense clustering inherent in drone-captured images by counteracting similar queries with a training-aware non-maximum *** denoising learning is a novel enhancement method inspired by adversarial learning,which improves the detection of numerous small targets by counteracting the effects of artificial spatial and semantic *** experiments on the VisDrone and UAVDT datasets substantiate the effectiveness of our approach,achieving a significant improvement in accuracy with a reduction in computational *** method achieves 31.9%and 21.1%AP on the VisDrone and UAVDT datasets,respectively,and has a faster inference speed,making it a competitive model in UAV image object detection.

关键词： UAV images transformer dense small object detection

Mechanical behavior and response mechanism of porous metal structures manufactured by laser powder bed fusion under compressive loading

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维普期刊数据库

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 737-749页

作者： Xuanming Cai Yang Hou Wei Zhang Zhiqiang Fan Yubo Gao Junyuan Wang Heyang Sun Zhujun Zhang Wenshu Yang School of Aerospace engineering North University of ChinaTaiyuan 030051China School of Materials Science and engineering North University of ChinaTaiyuan 030051China School of Astronautics Harbin Institute of TechnologyHarbin 150080China School of Mechanical engineering North University of ChinaTaiyuan 030051China shijiazhuang campus Army Engineering University of PLAShijiazhuang 050003China 65589 Unit 91 Detachment Daqing 163411China School of Materials Science and engineering Harbin Institute of TechnologyHarbin 150080China

Al Si10Mg porous protective structure often produces different damage forms under compressive loading,and these damage modes affect its protective *** order to well meet the service requirements,there is an urgent need to comprehensively understand the mechanical behavior and response mechanism of AlSi10Mg porous structures under compressive *** this paper,Al Si10Mg porous structures with three kinds of volume fractions are designed and optimized to meet the requirements of high-impact,strong-energy absorption,and lightweight *** mechanical behaviors of AlSi10Mg porous structures,including the stress-strain relationship,structural bearing state,deformation and damage modes,and energy absorption characteristics,were obtained through experimental studies at different loading *** damage pattern of the damage section indicates that AlSi10Mg porous structures have both ductile and brittle mechanical *** simulation studies show that the AlSi10Mg porous structure undergoes shear damage due to relative misalignment along the diagonal cross-section,and the damage location is almost at 45°to the load direction,which is the most direct cause of its structural damage,revealing the damage mechanism of AlSi10Mg porous structures under the compressive *** normalized energy absorption model constructed in the paper well interprets the energy absorption state of Al Si10Mg porous structures and gives the sensitive location of the structures,and the results of this paper provide important references for peers in structural design and optimization.

关键词： AlSi10Mg additive manufacture energy absorption characteristics damage by deformation mechanical behavior

Compressive sampling and reconstruction in shift-invariant spaces associated with the fractional Gabor transform

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Defence Technology（防务技术） 2022年第6期18卷 976-994页

作者： Qiang Wang Chen Meng Cheng Wang shijiazhuang campus Army Engineering UniversityShijiazhuangPR China

In this paper,we propose a compressive sampling and reconstruction system based on the shift-invariant space associated with the fractional Gabor *** this system,we aim to achieve the subNyquist sampling and accurate reconstruction for chirp-like signals containing time-varying *** the proposed scheme,we introduce the fractional Gabor transform to make a stable expansion for signals in the joint time-fractional-frequency *** the compressive sampling and reconstruction system is constructed under the compressive sensing and shift-invariant space *** establish the reconstruction model and propose a block multiple response extension of sparse Bayesian learning algorithm to improve the reconstruction *** reconstruction error for the proposed system is *** show that,with considerations of noises and mismatches,the total error is *** effectiveness of the proposed system is verified by numerical *** is shown that our proposed system outperforms the other systems state-of-the-art.

关键词： Compressive sampling Reconstruction Shift-invariant space Fractional gabor transform Chirp-like signals

Cross-linking density and aging constitutive model of HTPB coating under prestrain thermal accelerated aging

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Defence Technology（防务技术） 2020年第2期16卷 439-446页

作者： Yong-qiang Du Jian Zheng Chao Xiong shijiazhuang campus Army Engineering UniversityShijiazhuang 050003China

In order to study the cross-linking density and aging constitutive relationship of HTPB coating during storage,the thermal accelerated aging tests at 0%,3%,6%and 9%prestrains were carried *** crosslinking density of HTPB coating at different aging stages were tested using low-field^1 H NMR and the variation of cross-linking density was *** aging model of cross-linking density considering the chemical aging and the physical stretching factors was *** uniaxial tensile tests were carried out on HTPB coating at different aging stages and the cross-linking density was introduced into Ogden hyperelastic constitutive model as a characterization parameter of correction *** with uniaxial tensile test results,a prestrain aging constitutive model of HTPB coating was *** results show that the cross-linking density of HTPB coating increases rapidly at first and then slowly with the increase of thermal accelerated aging time without *** prestrain conditions,the crosslinking density of HTPB coating decreases at the early stage,and increases rapidly at first and then slowly at the middle and late stages of thermal accelerated *** correlation coefficients of aging model of cross-linking density and aging constitutive model with test results are R>0.9500 and R>0.9900 respectively,which can be used to accurately describe the cross-linking density and aging constitutive relationship of HTPB coating under prestrain accelerated thermal aging conditions.

关键词： Prestrain thermal accelerated aging Low-field^1H NMR Cross-linking density Aging constitutive model

Storage life prediction under pre-strained thermally-accelerated aging of HTPB coating using the change of crosslinking density

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Defence Technology（防务技术） 2021年第4期17卷 1387-1394页

作者： Yong-qiang Du Jian Zheng Gui-bo Yu shijiazhuang campus Army Engineering UniversityShijiazhuang050003China

In order to predict the storage life of a certain type of HTPB(hydroyl-terminated polybutadiene)coating at 25℃ and analyze the influence of pre-strain on the storage life,the accelerated aging tests of HTPB coating at 40℃,50℃,60℃,70℃ with the pre-strain of 0%,3%,6%,9%,respectively were carried *** variation regularity of the change of crosslinking density was analyzed and the aging model of HTPB coating under pre-strained thermally-accelerated aging was *** storage life of HTPB coating at 25℃ was estimated by using the Berthelot equation as the end point of the aging life with a 30% decrease in maximum *** results showed that the change of crosslinking density of HTPB coating increased with the increase of aging temperature and aging time,and decreased with the increase of *** 0% prestrain,the relationship between the change of crosslinking density of HTPB coating and the aging time can be described by the logarithmic model with the confidence probability greater than 99%.The stress relaxation phenomenon existed under 3%,6%and 9%pre-strained *** aging model considering chemical aging and pre-strain was established with the confidence probability greater than 90%.The storage life of HTPB coating was 15.2935 years at 25C under 0% prestrain,which was reduced by 13.9007%,75.6949% and 89.7859% under 3%,6% and 9% pre-strain,*** existence of pre-strain has a serious impact on the storage life of HTPB coating,therefore,the pre-strain should be avoided as much as possible during the actual storage.

关键词： HTPB coating Crosslinking density Aging model Storage life prediction Berthelot

Arbitrary-oriented target detection in large scene sar images

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Defence Technology（防务技术） 2020年第4期16卷 933-946页

作者： Zi-shuo Han Chun-ping Wang Qiang Fu shijiazhuang campus Army Engineering UniversityShijiazhuang050003China

Target detection in the field of synthetic aperture radar(SAR) has attracted considerable attention of researchers in national defense technology worldwide,owing to its unique advantages like high resolution and large scene image acquisition capabilities of ***,due to strong speckle noise and low signal-to-noise ratio,it is difficult to extract representative features of target from SAR images,which greatly inhibits the effectiveness of traditional *** order to address the above problems,a framework called contextual rotation region-based convolutional neural network(RCNN) with multilayer fusion is proposed in this ***,aimed to enable RCNN to perform target detection in large scene SAR images efficiently,maximum sliding strategy is applied to crop the large scene image into a series of sub-images before *** of using the highest-layer output for proposal generation and target detection,fusion feature maps with high resolution and rich semantic information are constructed by multilayer fusion ***,we put forwards rotation anchors to predict the minimum circumscribed rectangle of targets to reduce redundant detection ***,shadow areas serve as contextual features to provide extraneous information for the detector identify and locate targets *** results on the simulated large scene SAR image dataset show that the proposed method achieves a satisfactory performance in large scene SAR target detection.

关键词： Target detection Convolutional neural network Multilayer fusion Context information Synthetic aperture radar

Sensor radiation interception risk control in target tracking

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Defence Technology（防务技术） 2020年第3期16卷 695-704页

作者： Ce Pang Gan-lin Shan Wei-ning Ma Gong-guo Xu army engineering university Shijiazhuang CampusShijiazhuangHebei050003China

This paper is mainly on the problem of radiation interception risk control in sensor network for target ***,the sensor radiation interception risk is defined as the product of the interception probability and the cost caused by the ***,the radiation interception probability model and cost model are established,based on which the calculation method of interception risk can be ***,a sensor scheduling model of radiation risk control is established,taking the minimum interception risk as the objective *** the Hungarian algorithm is proposed to obtain sensor scheduling ***,simulation experiments are mad to prove the effectiveness of the methods proposed in this paper,which shows that compared with the sensor radiation interception probability control method,the interception risk control method can keep the sensor scheduling scheme in low risk as well as protect sensors of importance in the sensor network.

关键词： Radio frequency stealth Target tracking Interception probability Interception risk Hungary algorithm

A multi-sensor-system cooperative scheduling method for ground area detection and target tracking

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Frontiers of Information Technology & Electronic engineering 2023年第2期24卷 245-258页

作者： Yunpu ZHANG Qiang FU Ganlin SHAN Department of Electronic and Optical engineering Shijiazhuang CampusArmy Engineering UniversityShijiazhuang050003China

A multi-sensor-system cooperative scheduling method for multi-task collaboration is proposed in this *** studied the method for application in ground area detection and target *** aim of sensor scheduling is to select the optimal sensors to complete the assigned combat tasks and obtain the best combat ***,an area detection model was built,and the method of calculating the detection risk was proposed to quantify the detection benefits in ***,combining the information on road constraints and the Doppler blind zone,a ground target tracking model was established,in which the posterior Carmér-Rao lower bound was applied to evaluate future tracking ***,an objective function was developed which considers the requirements of detection,tracking,and energy consumption *** solving the objective function,the optimal sensor-scheduling scheme can be *** results showed that the proposed sensor-scheduling method can select suitable sensors to complete the required combat tasks,and provide good performance in terms of area detection,target tracking,and energy consumption control.

关键词： Sensor scheduling Area detection Target tracking Road constraints Doppler blind zone