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Effects of nano-metal oxide additives on ignition and combustion properties of MICs-boron rich fuels Def. Technol. (IF 5.1) Pub Date : 2024-03-29 Liang Hu, Danyang Liu, Kun Yang, Jianying Lu, Chao Shi, Jianyu Wang, Xinhang Liu, Lang Chen
Boron has been considered a promising powdered metal fuel for enhancing composite propellants' energy output due to its high energy density. However, the high ignition temperature and low combustion efficiency limit the application of boron powder due to the high boiling point of the boron oxide layer. Much research is ongoing to overcome these shortcomings, and one potential approach is to introduce
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Energy and blast performance of beryllium in a model thermobaric composition in comparison with aluminum and magnesium Def. Technol. (IF 5.1) Pub Date : 2024-03-28 Thomas M. Klapötke, Stanisław Cudziło, Waldemar A. Trzciński, Józef Paszula
A direct comparison is made between the effectiveness of Al, Mg, and Be powders as additional fuels in model thermobaric compositions containing 20% fuel, 20% ammonium perchlorate, and 60% RDX (1,3,5-Trinitro-1,3,5-triazacyclohexane) passivated with wax. Experimentally determined calorimetric measurements of the heat of detonation, along with the overpressure histories in an explosion chamber filled
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Energy release characteristics of PTFE/Al/TiH2 reactive jet with different TiH2 content Def. Technol. (IF 5.1) Pub Date : 2024-03-26 Chunlan Jiang, Jingbo Zhang, Rong Hu, Liang Mao, Ming Li
Titanium hydride (TiH), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH reactive liners with different TiH content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH reactive jet are tested by the
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Kinematic-mapping-model-guided analysis and optimization of 2-PSS&1-RR circular-rail parallel mechanism for fully steerable phased array antennas Def. Technol. (IF 5.1) Pub Date : 2024-03-26 Guodong Tan, Xiangfei Meng, Xuechao Duan, Lulu Cheng, Dingchao Niu, Shuai He, Dan Zhang
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Microstructure transformations and improving wear resistance of austenitic stainless steel additively fabricated by arc-based DED process Def. Technol. (IF 5.1) Pub Date : 2024-03-20 Ashish Yadav, Manu Srivastava, Prashant K. Jain, Sandeep Rathee
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Perspectives on additive manufacturing for warhead applications Def. Technol. (IF 5.1) Pub Date : 2024-03-19 Hao Xue, Qiang Zhou, Chuan Xiao, Guangyan Huang
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Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography Def. Technol. (IF 5.1) Pub Date : 2024-03-04 Pengyu Hu, Jiangpeng Wu, Zhengang Yan, Meng He, Chao Liang, Hao Bai
High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy, high resolution and high efficiency. However, it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm. To address these challenges
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A comprehensive review of radiation effects on solder alloys and solder joints Def. Technol. (IF 5.1) Pub Date : 2024-02-28 Norliza Ismail, Wan Yusmawati Wan Yusoff, Nor Azlian Abdul Manaf, Azuraida Amat, Nurazlin Ahmad, Emee Marina Salleh
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Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints Def. Technol. (IF 5.1) Pub Date : 2024-02-28 Ning Liu, Wenjiang Zhao, Yao Wang, Kai Shen, Zhong Su, Wenhao Qi, Yuedong Xie
In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of
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Color-polarization synergistic target detection method considering shadow interference Def. Technol. (IF 5.1) Pub Date : 2024-02-28 Bin Feng, Jinpei Xiao, Junchao Zhang, Lin Li, Yunlong Wu, Qing Ye
Aiming at the problem of shadow interference in UAV's ground reconnaissance, a color and polarization synergistic target detection method is proposed for -shadow interference, based on the influence of two physical characteristics (wavelength and polarization) under different illuminations. A valid fusion strategy is proposed via integrating two separate detection results on color and polarization
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Fracture behavior and mechanism of highly fragmented steel cylindrical shell under explosive loading Def. Technol. (IF 5.1) Pub Date : 2024-02-28 Kang Wang, Peng Chen, Xingyun Sun, Yufeng Liu, Jiayu Meng, Xiaoyuan Li, Xiongwei Zheng, Chuan Xiao
An in-depth understanding of the fracture behavior and mechanism of metallic shells under internal explosive loading can help develop material designs for warheads and regulate the quantity and mass distribution of the fragments formed. This study investigated the fragmentation performance of a new high-carbon silicon-manganese (HCSiMn) steel cylindrical shell through fragment recovery experiments
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A brand new green coating technology for realizing the regulation of spherical propellant energy release process Def. Technol. (IF 5.1) Pub Date : 2024-02-28 Wenhao Fan, Yajun Ding, Zhongliang Xiao
To achieve the controllable release of energy of nitrocellulose-based propellants, this paper combines the cellulose-based nanocomposites aqueous coating (Surelease®-NC) with fluidized bed coating equipment to successfully prepare the coated spherical propellant for the first time. The effects of fluidized bed coating temperature, air velocity, flow speed and atomization pressure on the adhesion rate
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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view Def. Technol. (IF 5.1) Pub Date : 2024-02-11 Wei Wang, Jiaqi Liu, Shiyao Lin, Baokui Geng, Zhongjiao Shi
In this paper, an integrated estimation guidance and control (IEGC) system is designed based on the command filtered backstepping approach for circular field-of-view (FOV) strapdown missiles. The three-dimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint. The boundary time-varying integral
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Transient response of doubly-curved bio-inspired composite shells resting on viscoelastic foundation subject to blast load using improved first-order shear theory and isogeometric approach Def. Technol. (IF 5.1) Pub Date : 2024-02-11 Thuy Tran Thi Thu, Tu Nguyen Anh, Hue Nguyen Thi, Hong Nguyen Thi
Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there
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Shock-induced chemical reaction characteristics of PTFE-Al-Bi2O3 reactive materials Def. Technol. (IF 5.1) Pub Date : 2024-02-11 Chunlan Jiang, Rong Hu, Jingbo Zhang, Zaicheng Wang, Liang Mao
A ternary system of PTFE/Al/BiO is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive material. The effects of BiO in the PTFE/Al/BiO on both mechanical properties and the energy release were investigated through various tests such as thermogravimetry-differential scanning calorimetry, adiabatic oxygen bomb test and split
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Experimental crushing behavior and energy absorption of angular gradient honeycomb structures under quasi-static and dynamic compression Def. Technol. (IF 5.1) Pub Date : 2024-02-10 Jiachen Li, Yuchen Wei, Hao Wu, Xingyu Shen, Mengqi Yuan
The high variability of shock in terrorist attacks poses a threat to people's lives and properties, necessitating the development of more effective protective structures. This study focuses on the angle gradient and proposes four different configurations of concave hexagonal honeycomb structures. The structures' macroscopic deformation behavior, stress-strain relationship, and energy dissipation characteristics
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High-speed tracked vehicle model order reduction for static and dynamic simulations Def. Technol. (IF 5.1) Pub Date : 2024-02-06 Luca Dimauro, Simone Venturini, Antonio Tota, Enrico Galvagno, Mauro Velardocchia
In this paper, a model order reduction strategy is adopted for the static and dynamic behaviour simulation of a high-speed tracked vehicle. The total number of degree of freedom of the structure is condensed through a selection of interface degrees of freedom and significant global mode shapes, for an approximated description of vehicle dynamic behaviour. The methodology is implemented in a customised
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Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5–16 km/s Def. Technol. (IF 5.1) Pub Date : 2024-02-01 Vladimir I. Kolpakov, Sergey V. Fedorov, Ekaterina P. Vinogradova, Irina A. Bolotina
Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range (from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the
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Study on damage mechanism and damage distribution of the rear plate under impact of debris cloud Def. Technol. (IF 5.1) Pub Date : 2024-01-30 Chenyang Wu, Xiaowei Chen, Qiguang He
The debris cloud generated by the hypervelocity impact (HVI) of orbiting space debris directly threatens the spacecraft. A full understanding of the damage mechanism of rear plate is useful for the optimal design of protective structures. In this study, the hypervelocity yaw impact of a cylindrical aluminum projectile on a double-layer aluminum plate is simulated by the FE-SPH adaptive method, and
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Probabilistic modeling of multifunction radars with autoregressive kernel mixture network Def. Technol. (IF 5.1) Pub Date : 2024-01-24 HanCong Feng, KaiLI. Jiang, ZhiXing Zhou, YuXin Zhao, KaiLun Tian, HaiXin Yan, Bin Tang
The task of modeling and analyzing intercepted multifunction radars (MFRs) pulse trains is vital for cognitive electronic reconnaissance. Existing methodologies predominantly rely on prior information or heavily constrained models, posing challenges for non-cooperative applications. This paper introduces a novel approach to model MFRs using a Bayesian network, where the conditional probability density
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Preparation and combustion properties of laminated sticks of B–CuO and B–Bi2O3 Def. Technol. (IF 5.1) Pub Date : 2024-01-22 Song Haoyu, Li Chenyang, Gao Fubing, Chongwei An, Li Shijiao, Zhan Xuan, He Jianchen
To explore the composite process of B–CuO and B–Bi2O3 two-component laminated sticks, obtain the corresponding sticks with good printing effect, and explore the energy release behavior. In this study, boron, copper oxide, and bismuth trioxide powders were dispersed in the dispersed phase (DMF) using F2602 as a binder, and the construction of two-component B–CuO, B–Bi2O3, three-component micro-composite
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Experimental investigation of spectral evolution in flash radiation by hypervelocity impact on aluminum plates Def. Technol. (IF 5.1) Pub Date : 2024-01-13 Xing Chen, Yonggang Lu, Zhiwen Li, Zhonghua Cui
In this study, a series of hypervelocity impact tests were carried out based on a two-stage light gas gun, and the sequence spectrum and radiation evolution data of the impact products under different impact conditions were obtained. The diameter of the projectile is 3–5 mm, the impact velocity is 3.13–6.58 km/s, and the chamber pressure is 0.56–990 Pa. The spectrum of ejected debris cloud in the 250–310 nm
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Blast waveform tailoring using controlled venting in blast simulators and shock tubes Def. Technol. (IF 5.1) Pub Date : 2024-01-08 Edward Chern Jinn Gan, Alex Remennikov, David Ritzel
A critical challenge of any blast simulation facility is in producing the widest possible pressure-impulse range for matching against equivalent high-explosive events. Shock tubes and blast simulators are often constrained with the lack of effective ways to control blast wave profiles and as a result have a limited performance range. Some wave shaping techniques employed in some facilities are reviewed
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Double casing warhead with sandwiched charge: The axial distribution of fragments velocities Def. Technol. (IF 5.1) Pub Date : 2023-12-30 Ping Ye, Yongxiang Dong, Qitian Sun, Peizhuo Shi, Wang Yao, Yongnan Li, Yujing Li, Mingze Li
The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity, and the previous work has presented a calculation formula to determine the maximum fragment velocity. The current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment velocity
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Quasi-static and dynamic compressive behaviour of additively manufactured Menger fractal cube structures Def. Technol. (IF 5.1) Pub Date : 2023-12-23 Damith Mohotti, Dakshitha Weerasinghe, Madhusha Bogahawaththage, Hongxu Wang, Kasun Wijesooriya, Paul J. Hazell
This paper presents the first-ever investigation of Menger fractal cubes' quasi-static compression and impact behaviour. Menger cubes with different void ratios were 3D printed using polylactic acid (PLA) with dimensions of 40×40×40 mm3. Three different orders of Menger cubes with different void ratios were considered, namely M1 with a void ratio of 0.26, M2 with a void ratio of 0.45, and M3 with a
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Explosion damage effects of aviation kerosene storage tank under strong ignition Def. Technol. (IF 5.1) Pub Date : 2023-12-22 Shixiang Song, Cheng Wang, Boyang Qiao, Gongtian Gu
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Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction Def. Technol. (IF 5.1) Pub Date : 2023-12-24 Yangtian Liu, Xiaopeng Yan, Qiang Liu, Tai An, Jian Dai
The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems. However, the electromagnetic environment of modern battlefields is complex, and the signal-to-noise ratio (SNR) of such environments is usually low, which makes it difficult to implement accurate recognition of radio fuzes. To solve the above problem, a radio fuze automatic modulation
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Non-dimensional analysis on blast wave propagation in foam concrete: Minimum thickness to avoid stress enhancement Def. Technol. (IF 5.1) Pub Date : 2023-12-22 Ya Yang, Xiangzhen Kong, Qin Fang
Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau stage. However, stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast load. To investigate this interesting phenomenon, a one-dimensional difference
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Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber Def. Technol. (IF 5.1) Pub Date : 2023-12-23 Jiri Balla, Roman Vitek, Dung Nguyen Van, Zbynek Krist, Hung Nguyen Van
The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the weapon. Earlier works, which did not consider the dynamic properties of the base of the weapon, did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing rests. For the analysis
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Towards complex scenes: A deep learning-based camouflaged people detection method for snapshot multispectral images Def. Technol. (IF 5.1) Pub Date : 2023-12-23 Shu Wang, Dawei Zeng, Yixuan Xu, Gonghan Yang, Feng Huang, Liqiong Chen
Camouflaged people are extremely expert in actively concealing themselves by effectively utilizing cover and the surrounding environment. Despite advancements in optical detection capabilities through imaging systems, including spectral, polarization, and infrared technologies, there is still a lack of effective real-time method for accurately detecting small-size and high-efficient camouflaged people
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Dinitrophenyl-oxadiazole compounds: Design strategy, synthesis, and properties of a series of new melt-cast explosives Def. Technol. (IF 5.1) Pub Date : 2023-12-21 Baolong Kuang, Tingwei Wang, Qamar-un-Nisa Tariq, Chao Zhang, Zhiming Xie, Zujia Lu, Jianguo Zhang
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RepDNet: A re-parameterization despeckling network for autonomous underwater side-scan sonar imaging with prior-knowledge customized convolution Def. Technol. (IF 5.1) Pub Date : 2023-12-19 Zhuoyi Li, Zhisen Wang, Deshan Chen, Tsz Leung Yip, Angelo P. Teixeira
Side-scan sonar (SSS) is now a prevalent instrument for large-scale seafloor topography measurements, deployable on an autonomous underwater vehicle (AUV) to execute fully automated underwater acoustic scanning imaging along a predetermined trajectory. However, SSS images often suffer from speckle noise caused by mutual interference between echoes, and limited AUV computational resources further hinder
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Target acquisition performance in the presence of JPEG image compression Def. Technol. (IF 5.1) Pub Date : 2023-12-20 Boban Bondžulić, Nenad Stojanović, Vladimir Lukin, Sergey A. Stankevich, Dimitrije Bujaković, Sergii Kryvenko
This paper presents an investigation on the effect of JPEG compression on the similarity between the target image and the background, where the similarity is further used to determine the degree of clutter in the image. Four new clutter metrics based on image quality assessment are introduced, among which the Haar wavelet-based perceptual similarity index, known as HaarPSI, provides the best target
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Impact response and energy absorption of metallic buffer with entangled wire mesh damper Def. Technol. (IF 5.1) Pub Date : 2023-12-18 Chao Zheng, Jun Wu, Mangong Zhang, Xin Xue
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Dynamic response of honeycomb-FGS shells subjected to the dynamic loading using non-polynomial higher-order IGA Def. Technol. (IF 5.1) Pub Date : 2023-12-16 Pham Binh Le, Trung-Thanh Tran
The main goal of this study is to use higher-order isogeometric analysis (IGA) to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials (FGM) skin layers (namely honeycomb-FGS shells) subjected to dynamic loading. Touratier's non-polynomial higher-order shear deformation theory (HSDT) is used due to its simplicity and performance
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Revealing Al–O/Al–F reaction dynamic effects on the combustion of aluminum nanoparticles in oxygen/fluorine containing environments: A reactive molecular dynamics study meshing together experimental validation Def. Technol. (IF 5.1) Pub Date : 2023-12-12 Gang Li, Chuande Zhao, Qian Yu, Fang Yang, Jie Chen
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Ballistic performance of spaced multi-ply soft fabrics: Experimental and numerical investigation Def. Technol. (IF 5.1) Pub Date : 2023-12-11 Zhongwei Zhang, Xiaoning Yang, Yuan Lin, Ziming Xiong, Yuhang Xiang, Yi Zhou, Mingyang Wang
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The effect of reactive plasticizer on viscoelastic and mechanical properties of solid rocket propellants based on different types of HTPB resin Def. Technol. (IF 5.1) Pub Date : 2023-12-10 Tihomir Kovačević, Slavko Mijatov, Jelena Gržetić, Suzana Cakić, Bojana Fidanovski, Saša Brzić
Conventional plasticizers deteriorate mechanical and viscoelastic properties of the propellants due to their migration upon aging and long-term storage, which affects reliability and safety properties during exploitation. To address this issue, conventional plasticizer, dioctyl adipate (DOA), is replaced by reactive one, castor oil (CO). In addition, three different types of HTPB were used to obtain
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Assessing target optical camouflage effects using brain functional networks: A feasibility study Def. Technol. (IF 5.1) Pub Date : 2023-12-07 Zhou Yu, Li Xue, Weidong Xu, Jun Liu, Qi Jia, Jianghua Hu, Jidong Wu
Brain functional networks model the brain's ability to exchange information across different regions, aiding in the understanding of the cognitive process of human visual attention during target searching, thereby contributing to the advancement of camouflage evaluation. In this study, images with various camouflage effects were presented to observers to generate electroencephalography (EEG) signals
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AP assembled on ultrafine aluminum particle and its application to NEPE propellant Def. Technol. (IF 5.1) Pub Date : 2023-12-01 Huixin Wang, Qiang Li, Hui Ren, Liangjun Xie, Tingting Liu, Zhihong Chen
Coating modification is an important way to enhance the reactivity of aluminum powder. In this paper, ammonium perchlorate and aluminum powder were assembled into energetic microunits by liquid deposition method. Spherical particles with AP as shell and ultrafine aluminum powder as the core (Al@AP) were gained. The micromorphology results show that the coated particles are about 5 μm, and the coating
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Multidisciplinary design optimization of a dual-spin guided vehicle Def. Technol. (IF 5.1) Pub Date : 2023-11-29 Jalal Karimi, Mohammad Reza Rajabi, Seyed Hossein Sadati, Seyed Mahid Hosseini
In this research, a Multidisciplinary Design Optimization approach is proposed for the dual-spin guided flying projectile design considering external and internal parts of the body as design variables. In this way, a parametric formulation is developed. All related disciplines, including structure, aerodynamics, guidance, and control are considered. Minimum total mass, maximum aerodynamic control effectiveness
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An air combat maneuver pattern extraction based on time series segmentation and clustering analysis Def. Technol. (IF 5.1) Pub Date : 2023-11-23 Zhifei Xi, Yingxin Kou, Zhanwu Li, Yue Lv, You Li
Target maneuver recognition is a prerequisite for air combat situation awareness, trajectory prediction, threat assessment and maneuver decision. To get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data, and automatically and adaptively complete the task of extracting the target maneuver pattern, in this paper, an air combat maneuver pattern
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Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking Def. Technol. (IF 5.1) Pub Date : 2023-11-23 Luis Quinto, Pedro Pinheiro, Sergio B. Goncalves, Ivo Roupa, Paula Simoes, Miguel Tavares Da Silva
Modern conflicts demand substantial physical and psychological exertion, often resulting in fatigue and diminished combat or operational readiness. Several exoskeletons have been developed recently to address these challenges, presenting various limitations that affect their operational or everyday usability. This article evaluates the performance of a dual-purpose passive ankle exoskeleton developed
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A low-profile metamaterial absorber with ultrawideband reflectionless and wide-angular stability Def. Technol. (IF 5.1) Pub Date : 2023-11-25 Feihong Lin, Zhongming Yan, Ping Wang, Yu Wang, Hongcheng Zhou, Haoran Lu
An ultrawideband reflectionless metamaterial absorber (MA) is proposed by replacing the metallic ground with the complementary split-ring resonator (CSRR) structure. The proposed MA exhibits −10 dB reflectivity spectrum from 1 GHz to 20 GHz, which maintains more than absorption from 1.5 GHz to 20 GHz. Furthermore, it achieves angle stability for TE and TM polarization at oblique incident angles up
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Mussel-inspired PTW@PDA composites for developing high-energy gun propellants with reduced erosion and enhanced mechanical strength Def. Technol. (IF 5.1) Pub Date : 2023-11-23 Xijin Wang, Zhitao Liu, Pengfei Sun, Feiyun Chen, Bin Xu, Xin Liao
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Experimental and numerical study of effecting core configurations on the static and dynamic behavior of honeycomb plate with aluminum material Def. Technol. (IF 5.1) Pub Date : 2023-11-21 Nehad Abid Allah H, Fatima Mohammed K. AL-Fatlwe, Muna Ali Talib
The sandwich panel incorporated a honeycomb core, a widely utilized composite structure recognized as a fundamental classification of composite materials. Comprised a core resembling a honeycomb, possessing thickness and softness, and is flank by rigid face sheets that sandwich various shapes and materials. In this paper, an investigation of static and dynamic analysis of aluminum honeycomb sandwich
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A novel multi-resolution network for the open-circuit faults diagnosis of automatic ramming drive system Def. Technol. (IF 5.1) Pub Date : 2023-11-21 Liuxuan Wei, Linfang Qian, Manyi Wang, Minghao Tong, Yilin Jiang, Ming Li
The open-circuit fault is one of the most common faults of the automatic ramming drive system (ARDS), and it can be categorized into the open-phase faults of Permanent Magnet Synchronous Motor (PMSM) and the open-circuit faults of Voltage Source Inverter (VSI). The stator current serves as a common indicator for detecting open-circuit faults. Due to the identical changes of the stator current between
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Bending results of graphene origami reinforced doubly curved shell Def. Technol. (IF 5.1) Pub Date : 2023-11-18 Nan Yang, Yunhe Zou, Mohammad Arefi
The present work investigates higher order stress, strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper (Cu) core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal loads. The effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both
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Experimental study of 3D printed carbon fibre sandwich structures for lightweight applications Def. Technol. (IF 5.1) Pub Date : 2023-11-14 Solaiprakash Vellaisamy, Raguraman Munusamy
Honeycomb sandwich structures are widely used in lightweight applications. Usually, these structures are subjected to extreme loading conditions, leading to potential failures due to delamination and debonding between the face sheet and the honeycomb core. Therefore, the present study is focused on the mechanical characterisation of honeycomb sandwich structures fabricated using advanced 3D printing
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Multi-UAV cooperative maneuver decision-making for pursuit-evasion using improved MADRL Def. Technol. (IF 5.1) Pub Date : 2023-11-13 Delin Luo, Zihao Fan, Ziyi Yang, Yang Xu
Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning (MADRL) is proposed. In this method, an improved CommNet network based on a communication mechanism is introduced into a deep reinforcement learning algorithm to solve the multi-agent problem. A layer of gated recurrent unit (GRU) is added
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Evolution of molecular structure of TATB under shock loading from transient Raman spectroscopic technique Def. Technol. (IF 5.1) Pub Date : 2023-11-13 Hongliang Kang, Xue Yang, Wenshuo Yuan, Lei Yang, Xinghan Li, Fusheng Liu, Zhengtang Liu, Qijun Liu
By combination of the transient Raman spectroscopic measurement and the density functional theoretical calculations, the structural evolution and stability of TATB under shock compression was investigated. Due to the improvement in synchronization control between two-stage light gas gun and the transient Raman spectra acquisition, as well as the sample preparation, the Raman peak of the N–O mode of
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Anti-explosion performance and dynamic response of an innovative multi-layer composite explosive containment vessel Def. Technol. (IF 5.1) Pub Date : 2023-11-10 Zhen Wang, Heng Chen, Qi Yuan, Wenbin Gu, Xingbo Xie, Hongwei Li
An innovative multi-layer composite explosion containment vessel (CECV) utilizing a sliding steel plate-aluminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel (SECV). Firstly, a series of experiments and finite element (FE) simulations of internal explosions are implemented to understand the basic anti-explosion
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Lateral ring compression test applied to a small caliber steel jacket: Identification of a constitutive model Def. Technol. (IF 5.1) Pub Date : 2023-11-08 Yann Coget, Yaël Demarty, Christophe Czarnota, Anthony Bracq, Jean-Sebastien Brest, Alexis Rusinek
The evolution of threats and scenarios requires continuous performance improvements of ballistic protections for armed forces. From a modeling point of view, it is necessary to use sufficiently precise material behavior models to accurately describe the phenomena observed during the impact of a projectile on a protective equipment. In this context, the goal of this paper is to characterize the behavior
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Recent progress on impact induced reaction mechanism of reactive alloys Def. Technol. (IF 5.1) Pub Date : 2023-11-07 Yansong Yang, Chuanting Wang, Yuanpei Meng, Yue Ma, Lei Guo, Yuan He, Zhichao Sun, Yong He
In recent years, in order to improve the destructive effectiveness of munitions, the use of new types of destructive elements is an important way to improve destructive effectiveness. As a new type of reactive material, reactive alloy contains a large portion of reactive metal elements (Al, Mg, Ti, Zr, etc.), which breaks up under high-velocity impact conditions, generating a large number of high-temperature
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Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles Def. Technol. (IF 5.1) Pub Date : 2023-11-11 Wei Wang, Yuchen Wang, Shiwei Chen, Yongcang Guo, Zhongjiao Shi
This paper investigates the design of an attitude autopilot for a dual-channel controlled spinning glide-guided projectile (SGGP), addressing model uncertainties and external disturbances. Based on fixed-time stable theory, a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects, irrespective of initial conditions. By introducing an
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Construction of core@double-shell structured energetic composites with simultaneously enhanced thermal stability and safety performance Def. Technol. (IF 5.1) Pub Date : 2023-11-10 Peng Wang, Wen Qian, Ruolei Zhong, Fangfang He, Xin Li, Jie Chen, Li Meng, Yinshuang Sun, Guansong He
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A reduced combustion mechanism of ammonia/diesel optimized with multi-objective genetic algorithm Def. Technol. (IF 5.1) Pub Date : 2023-11-09 Wanchen Sun, Shaodian Lin, Hao Zhang, Liang Guo, Wenpeng Zeng, Genan Zhu, Mengqi Jiang
For the deep understanding on combustion of ammonia/diesel, this study develops a reduced mechanism of ammonia/diesel with 227 species and 937 reactions. The sub-mechanism on ammonia/interactions of N-based and C-based species (N–C)/NOx is optimized using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) with 200 generations. The optimized mechanism (named as 937b) is validated against combustion
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Disturbances rejection optimization based on improved two-degree-of-freedom LADRC for permanent magnet synchronous motor systems Def. Technol. (IF 5.1) Pub Date : 2023-11-08 Chenggang Wang, Jianhu Yan, Wenlong Li, Liang Shan, Le Sun
Permanent magnet synchronous motor (PMSM) speed control systems with conventional linear active disturbance rejection control (CLADRC) strategy encounter issues regarding the coupling between dynamic response and disturbance suppression and have poor performance in suppressing complex nonlinear disturbances. In order to address these issues, this paper proposes an improved two-degree-of-freedom LADRC
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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials Def. Technol. (IF 5.1) Pub Date : 2023-11-08 Rui Zhao, Jian Zheng, Jin Guo, Yunbo Shi, Hengzhen Feng, Jun Tang, Jun Liu
In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 kHz–100 kHz, this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties, which is configured by hybrid arc and sharp-angle convergent star-shaped lattices. The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped
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Isomeric fluorescence sensors for wide range detection of ionizing radiations Def. Technol. (IF 5.1) Pub Date : 2023-11-08 Jimin Han, Tianyu Yang, Li Yang, Yuanjian Li
In order to achieve a wider range of ionizing radiations detection, novel fluorescence sensing materials have been developed that utilize the fluorescence enhancement phenomenon caused by the intramolecular photoinduced electron transfer (PET) effect. Two perylene diimide isomers PDI-P and PDI-B were designed and synthesized, and their molecular structures were characterized by high-resolution Fourier