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Chinese Journal of Aeronautics 2024年第5期37卷 349-362页

作者： Zhengjie LI Yujie WEI Junwei XIE Haowei ZHANG Yu TIAN Air and Missile defense College Air Force Engineering UniversityXi’an 710051China Air force Xi’an Flying College Xi’an 710300China Air and Missile defense Institute Air Force Research InstituteBeijing 100085China School of Economics and Management Beihang UniversityBeijing 100191China

This paper investigates the problem of Joint Radar Node Selection and Power Allocation(JRNSPA)in the Multiple Radar System(MRS)in the blanket jamming *** radar node independently tracks moving target and subsequently transmits the raw observation data to the fusion center,which formulates a centralized tracking network *** order to establish a practical blanket jamming environment,we suppose that each target carries the self-defense jammer which automatically implements blanket jamming to the radar nodes that exceed the preset interception ***,the Predicted Conditional Cramer-Rao Lower Bound(PC-CRLB)is derived and utilized as the tracking accuracy *** at ensuring both the tracking performance and the Low Probability of Intercept(LPI)performance,the resource-saving scheduling model is formulated to minimize the transmit power consumption while meeting the requirements of tracking ***,the Modified Zoutendijk Method Of Feasible Directions(MZMFD)-based two-stage solution technique is adopted to solve the formulated non-convex optimization *** results show the effectiveness of the proposed JRNSPA scheme.

关键词： Multiple Radar System(MRS) Centralized target tracking Resource scheduling Blanket jamming Low Probability of Intercept(LPI)

Investigation of hydroxyl-terminated polybutadiene propellant breaking characteristics and mechanism impacted by submerged cavitation water jet

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Defence Technology（防务技术） 2024年第3期33卷 559-572页

作者： Wenjun Zhou Meng Zhao Bo Liu Youzhi Ma Youzhi Zhang Xuanjun Wang Zhijian Laboratory Rocket Force University of EngineeringXi’an710025China

A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking *** propellant's breaking modes and mechanical process under SCWJ impact are *** study aims to understand those impact breaking *** hydroxyl-terminated polybutadiene(HTPB)propellant was chosen as the research material,and a self-designed test system was used to conduct impact tests at four different working *** high-speed camera characterized crack propagation,and the DIC method calculated strain change during the impact ***,micro and macro fracture morphologies were characterized by scanning electron microscope(SEM)and computed tomography(CT)*** results reveal that the compressive strain concentration region locates right below the nozzle,and the shear strain region distributes symmetrically with the jet axis,which increases to 4% at first 16th ms,the compressive strain rises to 2% and 6% in the axial and transverse direction,*** two tensile cracks formed first at the compression strain concentrate region,and there generate many shear cracks around the tensile cracks,and those shear cracks that develop and aggregate cause the cracks to become wider and cut through the tensile cracks,forming the tensile-shear cracks and the impact parts eventually *** HTPB propellant forms a breaking hole shaped conical after impact 10 *** mass loss increases by 17 times at maximum,with the working pressure increasing by three ***,the damage value of the breaking hole remaining on the surface increases by 7.8 times while 2.9 times in the depth of the breaking *** breaking efficiency is closely affected by working *** failure modes of HTPB impacted by SCWJ are classified as tensile crack-dominated and tensile-shear crack-dominated damage mechanisms.

关键词： Submerged cavitation water jet Hydroxyl-terminated polybutadiene propellant Breaking characteristics Failure modes

Spin-up and Spin-Down Times of Rotational Air Flow Depended on Mean Air Velocity and Surface Roughness on Inner Surface in Cylindrical Vortex Chamber

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Journal of Thermal Science 2004年第1期13卷 46-55页

作者： Akira Ogawa Hiroyuki Murakami Department of Mechanical Eng.College of Eng. Nihon UniversityT-963.TokusadaTamura-machiKooriyama-CityJapanThe Marine Self Defense Forcethe Defense AgencyJapan

The spin-up time TA in the spin-up process and spin-down time TD in the spin-down process of rotational air flow in the cylindrical vortex chamber with three kinds of the artificial surface roughness were investigated. One of the most different characteristics between the smooth and rough surface conditions was the spin-down time TD. Also the transient response of the tangential velocity on the spin-up process was analyzed numerically and this result was compared with the experimental results. The above stated results are reported here in detail.

关键词： vortex chamber spin-up time spin-down time transient response surface roughness.

Estimation of the Radial Distribution of the Tangential Velocity in a Vortex Chamber

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Journal of Thermal Science 2009年第1期18卷 27-32页

作者： Akira OGAWA Tsuyoshi IKARI Hiroyuki MURAKAMI Kouhei SATHO T-110-0011 Minowa 2-14-7 Taitou-Ku Tokyo Japan AQUAS .Co.Ltd. Japan the marine self defense force Japan GMA Co.Ltd. Japan

The estimation of maximum tangential velocity becomes a very important factor for the estimation of performancesof the vortex chamber. In this paper, a proposed flow model of how to estimate the maximum tangential velocity inthe special form of the vortex chamber is described in detail. The pressure drop basing upon the rapid expansion byflowing from the inlet pipe into the cyclone body is estimated as half of the dynamic pressure in the inlet pipe.

关键词： Vortex chamber tangential velocity angular momentum flux Reynolds number

self-adaptive combination method for temporal evidence based on negotiation strategy

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Science China(Information Sciences) 2020年第11期63卷 56-68页

作者： Yafei SONG Jingwei ZHU Lei LEI Xiaodan WANG College of Air and Missile defense Air Force Engineering University Institute of High Technology Air Force Engineering University College of Information and Navigation Air Force Engineering University

In temporal information fusion, the information collected by sensors is obtained dynamically with the passage of time. Unlike the spatial information fusion, temporal fusion should be dynamic. Evidence theory has been applied to fuse temporal and spatial information; however, existing temporal fusion methods do not treat conflicting and non-conflicting evidence sources distinctively. Moreover, unlike spatial evidence sources, which are obtained simultaneously, temporal evidence sources cannot be evaluated simultaneously to obtain their degree of reliability. Thus, it is necessary to develop a method for temporal evidence *** this paper, a self-adaptive combination method for temporal evidence is proposed based on the negotiation strategy. In the proposed method, a set called an evidence set is constructed by the cumulative temporal fusion results of the previous moment, current moment, and future moment. The evidence set is evaluated as conflicting or non-conflicting according to the maximum power pignistic probability distance between each pair of evidence sources in the set. Then, temporal evidence sources are self-adaptively combined by different methods according to the degree of conflict. Numerical experiments were conducted to evaluate the performance of the proposed method. The results indicated that the proposed method is sufficiently effective and robust to support decision making.

关键词： information fusion evidence theory temporal fusion self-adaptive combination negotiation strategy

Single-layer broadband planar antenna using ultrathin high-efficiency focusing metasurfaces

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Chinese Physics B 2017年第5期26卷 371-375页

作者：侯海生王光明李海鹏郭文龙李唐景蔡通 Air and Missile defense College Air Force Engineering UniversityXi'an 710051China

Phase gradient metasurfaces（PGMS） offer a fascinating ability to control the amplitude and phase of the electromagnetic（EM） waves on a subwavelength scale, resulting in new applications of designing novel microwave devices with improved performances. In this paper, a reflective symmetrical element, consisting of orthogonally I-shaped structures, has been demonstrated with an approximately parallel phase response from 15 GHz to 22 GHz, which results in an interesting wideband property. For practical design, a planar antenna is implemented by a well-optimized focusing metasurface and excited by a self-designed Vivaldi antenna at the focus. Numerical and experimental results coincide well. The planar antenna has a series of merits such as a wide 3-d B gain bandwidth of 15–22 GHz, an average gain enhancement of 16 d B, a comparable aperture efficiency of better than 45% at 18 GHz, and also a simple fabrication process. The proposed reflective metasurface opens up a new avenue to design wideband microwave devices.

关键词： antenna reflective planar broadband focusing fascinating bandwidth microwave comparable shaped

Joint target assignment and power allocation in the netted C-MIMO radar when tracking multi-targets in the presence of self-defense blanket jamming

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Defence Technology（防务技术） 2023年第6期24卷 414-427页

作者： Zhengjie Li Junwei Xie Haowei Zhang Jiahao Xie Air and Missile defense College Air Force Engineering UniversityXi'an 710051China Space Engineering University of Strategic Support force Beijing 101416China

The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking *** resource management can greatly ensure the combat capability of the *** this paper,based on the netted collocated multiple input multiple output(CMIMO)radar,an effective joint target assignment and power allocation(JTAPA)strategy for tracking multi-targets under self-defense blanket jamming is *** architecture based on the distributed fusion is used in the radar network to estimate target state *** deriving the predicted conditional Cramer-Rao lower bound(PC-CRLB)based on the obtained state estimation information,the objective function is *** maximize the worst case tracking accuracy,the proposed JTAPA strategy implements an online target assignment and power allocation of all active nodes,subject to some resource *** the formulated JTAPA is non-convex,we propose an efficient two-step solution *** terms of the simulation results,the proposed algorithm can effectively improve tracking performance in the worst case.

关键词： Netted radar system MIMO Target assignment Power allocation Multi-targets tracking self-defense blanket jamming

From Network Functions to NetApps: The 5GASP Methodology

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Computers, Materials & Continua 2022年第5期71卷 4115-4134页

作者： Jorge Gallego-Madrid Ramon Sanchez-Iborra Antonio Skarmeta University of Murcia Murcia30100Spain University Center of defense General Air Force AcademySan Javier30720Spain

As the 5G ecosystem continues its consolidation,the testing and validation of the innovations achieved by integrators and verticals service providers is of preponderant *** this line,5GASP is a European H2020-funded project that aims at easing the idea-to-market process through the creation of an European testbed that is fully automated and self-service,in order to foster rapid development and testing of new and innovative 5G Network Applications(NetApps).The main objective of this paper is to present the 5GASP’s unified methodology to design,develop and onboard NetApps within the scope of different vertical services,letting them use specific 5G ***,we examine the whole 5GASP process in a tutorial fashion by adopting a specific use case focusing on the integration of a virtual On-Board Unit(vOBU)service that permits offloading processing from the attached vehicle and serving data-access *** demonstrated,the presented workflow permits the agile,rigorous,and safe development,testing and certification of NetApps,which will enable valuable in-network services for 5G and beyond infrastructures.

关键词： 5G NetApp 5GASP vOBU

Evaluation method and optimization strategies of resilience for air&space defense system of systems based on kill network theory and improved self-information quantity

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Defence Technology（防务技术） 2023年第3期21卷 219-239页

作者： Qi Han Bo Pang Sen Li Ning Li Peng-song Guo Cheng-li Fan Wei-min Li Air defense and Antimissile School Air Force Engineering UniversityXi’an710051China Graduate School Air Force Engineering UniversityXi’an710051China Information and Navigation School Air Force Engineering UniversityXi’an710077China School of Automation Science and Engineering Xi'an Jiaotong UniversityXi'an710049China

Resilience of air&space defense system of systems(SoSs)is critical to national air defense ***,the research on it is still *** this study,the resilience of air&space defense SoSs is firstly defined and the kill network theory is established by combining super network and kill chain *** cases of the SoSs are considered:(a)The kill chains are relatively homogenous;(b)The kill chains are relatively ***,two capability assessment methods,which are based on the number of kill chains and improved self-information quantity,respectively,are *** improved self-information quantity modeled based on nodes and edges can achieve qualitative and quantitative assessment of the combat capability by using linguistic Pythagorean fuzzy ***,a resilient evaluation index consisting of risk response,survivability,and quick recovery is proposed ***,network models for regional air defense and anti-missile SoSs are established respectively,and the resilience measurement results are verified and analyzed under different attack and recovery strategies,and the optimization strategies are also *** proposed theory and method can meet different demands to evaluate combat capability and optimize resilience of various types of air&space defense and similar SoSs.

关键词： network optimization theory

EasyModel:A Refinement-Based Modeling and Verification Approach for self-Adaptive Software

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Journal of Computer Science & Technology 2020年第5期35卷 1016-1046页

作者： De-Shuai Han Qi-Liang Yang Jian-Chun Xing Guang-Lian Ma College of Combat Support Rocket Force University of EngineeringXVan 710025China College of defense Engineering Army Engineering University of PL ANanjing 210007China Teaching and Research Support Center Rocket Force University of EngineeringXi'an 710025China

self-adaptive software(SAS)is gaining popularity as it can reconfigure itself in response to the dynamic changes in the operational context or ***,early modeling and formal analysis of SAS systems becomes increasingly difficult,as the system scale and complexity is rapidly *** tackle the modeling difficulty of SAS systems,we present a refinement-based modeling and verification approach called Easy *** Model integrates the intuitive Unified Modeling Language(UML)model with the stepwise refinement Event-B ***,EasyModel:1)creates a UML profile called AdaptML that provides an explicit description of SAS characteristics,2)proposes a refinement modeling mechanism for SAS systems that can deal with system modeling complexity,3)offers a model transformation approach and bridges the gap between the design model and the formal model of SAS systems,and 4)provides an efficient way to verify and guarantee the correct behaviour of SAS *** validate EasyModel,we present an example application and a subject-based *** results demonstrate that EasyModel can effectively reduce the modeling and formal verification difficulty of SAS systems,and can incorporate the intuitive merit of UML and the correct-by-const ruction merit of Event-B.

关键词： self-adaptive software formal modeling Event-B refinement correct-by-construction