Defence Technology(防务技术)最新文献_第6页

Equivalent loading method for the thin-walled floors of armored vehicles with bottom explosion impacts 底部爆炸冲击下装甲车辆薄壁底板的等效加载方法

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-10-01 DOI: 10.1016/j.dt.2025.06.010

Weiwei Qin , Jiahao He , Shaoyan Zhang , Tuzao Yao , Jing Tang , Xianhui Wang , Xiaowang Sun , Tao Wang , Qiang Zhou

The high cost and low efficiency of full-scale vehicle experiments and numerical simulations limit the efficient development of armored vehicle occupant protection systems. The floor-occupant-seat local simulation model provides an alternative solution for quickly evaluating the performance of occupant protection systems. However, the error and rationality of the loading of the thin-walled floor in the local model cannot be ignored. This study proposed an equivalent loading method for the local model, which includes two parts: the dimensionality reduction method for acceleration matrix and the joint optimization framework for equivalent node coordinates. In the dimensionality reduction method, the dimension of the acceleration matrix was reduced based on the improved kernel principal component analysis (KPCA), and a dynamic variable bandwidth was introduced to address the limitation of failing to effectively measure the similarity between acceleration data in conventional KPCA. In addition, a least squares problem with forced displacement constraints was constructed to solve the correction matrix, thereby achieving the scale restoration process of the principal component acceleration matrix. The joint optimization framework for coordinates consists of the error assessment of response time histories (EARTH) and Bayesian optimization. In this framework, the local loading error of the equivalent acceleration matrix is taken as the Bayesian optimization objective, which is quantified and scored by EARTH. The expected improvement acquisition function was used to select the new set of the equivalent acceleration node coordinates for the self-updating optimization of the observation dataset and Gaussian process surrogate model. We reduced the dimension of the acceleration matrix from 2256 to 7, while retaining 91% of the information features. The comprehensive error score of occupant's lower limb response in the local model increased from 58.5% to 80.4%. The proposed equivalent loading method provides a solution for the rapid and reliable development of occupant protection systems.

整车实验和数值模拟的高成本和低效率限制了装甲车辆乘员保护系统的高效开发。地板-乘员-座位局部仿真模型为快速评估乘员保护系统的性能提供了另一种解决方案。然而，薄壁楼盖局部模型加载的误差和合理性也不容忽视。本文提出了一种局部模型的等效加载方法，该方法包括加速度矩阵降维方法和等效节点坐标的联合优化框架两部分。在降维方法中，基于改进的核主成分分析（KPCA）对加速度矩阵进行降维，并引入动态可变带宽，解决了传统核主成分分析无法有效度量加速度数据之间相似度的局限性。此外，构造带强迫位移约束的最小二乘问题求解修正矩阵，从而实现主分量加速度矩阵的尺度恢复过程。该联合优化框架由响应时间历史误差评估（EARTH）和贝叶斯优化组成。该框架以等效加速度矩阵的局部加载误差为贝叶斯优化目标，利用EARTH对其进行量化和评分。利用期望改进获取函数选择新的等效加速节点坐标集，对观测数据集和高斯过程代理模型进行自更新优化。我们将加速度矩阵的维数从2256降到了7，同时保留了91%的信息特征。局部模型中乘员下肢反应综合误差评分由58.5%提高到80.4%。提出的等效加载方法为乘员保护系统的快速、可靠发展提供了一种解决方案。

{"title":"Equivalent loading method for the thin-walled floors of armored vehicles with bottom explosion impacts","authors":"Weiwei Qin , Jiahao He , Shaoyan Zhang , Tuzao Yao , Jing Tang , Xianhui Wang , Xiaowang Sun , Tao Wang , Qiang Zhou","doi":"10.1016/j.dt.2025.06.010","DOIUrl":"10.1016/j.dt.2025.06.010","url":null,"abstract":"<div><div>The high cost and low efficiency of full-scale vehicle experiments and numerical simulations limit the efficient development of armored vehicle occupant protection systems. The floor-occupant-seat local simulation model provides an alternative solution for quickly evaluating the performance of occupant protection systems. However, the error and rationality of the loading of the thin-walled floor in the local model cannot be ignored. This study proposed an equivalent loading method for the local model, which includes two parts: the dimensionality reduction method for acceleration matrix and the joint optimization framework for equivalent node coordinates. In the dimensionality reduction method, the dimension of the acceleration matrix was reduced based on the improved kernel principal component analysis (KPCA), and a dynamic variable bandwidth was introduced to address the limitation of failing to effectively measure the similarity between acceleration data in conventional KPCA. In addition, a least squares problem with forced displacement constraints was constructed to solve the correction matrix, thereby achieving the scale restoration process of the principal component acceleration matrix. The joint optimization framework for coordinates consists of the error assessment of response time histories (EARTH) and Bayesian optimization. In this framework, the local loading error of the equivalent acceleration matrix is taken as the Bayesian optimization objective, which is quantified and scored by EARTH. The expected improvement acquisition function was used to select the new set of the equivalent acceleration node coordinates for the self-updating optimization of the observation dataset and Gaussian process surrogate model. We reduced the dimension of the acceleration matrix from 2256 to 7, while retaining 91% of the information features. The comprehensive error score of occupant's lower limb response in the local model increased from 58.5% to 80.4%. The proposed equivalent loading method provides a solution for the rapid and reliable development of occupant protection systems.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"52 ","pages":"Pages 184-206"},"PeriodicalIF":5.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145278358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic response characteristics of metal cylindrical shell driven by explosive charge with waveform regulator 带波形调节器的装药驱动金属圆柱壳的动态响应特性

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-10-01 DOI: 10.1016/j.dt.2025.05.015

Weixin Bi , Weibing Li , Junbao Li , Heyang Xu , Wenbin Li

Waveform regulator in charge is a method that can realize multi-source detonation wave superposition through a single point detonation. The method does not need to weaken the strength of shell, and relies on the high stress generated by superposition to cut shell into regular fragments. Additionally, it can be combined with different initiation methods to alter the fragmentation outcomes. In this study, aiming at the fracture strain of metal cylindrical shell driven by explosive charge with waveform regulator, theoretical analysis was first adopted to obtain the prediction model of the fracture strain of cylindrical shell with waveform regulator and the model of the axial distribution of the stress concentration factor. On this basis, both theoretical analysis and numerical models were utilized to investigate the effect of waveform regulator on the initial velocity of fragments. Finally, experiments were conducted to validate the fracture strain prediction model for cylindrical shell with waveform regulator. The research results show that the collision angles of the detonation waves at different axial positions are different, which leads to the stress concentration factor on the shell presenting a trend of gradually decreasing, then sharply increasing, and then rapidly decreasing along the axial direction. Additionally, the changes in the slot spacing and the thickness of outer charge will also affect the stress concentration factor, and the influence of outer charge thickness is relatively large. The smaller the ratio of charge volume to waveform regulator volume, the larger the axial sparse wave intensity and the more the fragment initial velocity decrease. From the initiation end to the non-initiation end, the failure modes of the shell sequentially change from pure shear, to mixed tensile-shear, and finally to pure tensile failure. The experimental results are in good agreement with the calculated results of the fracture strain model, and the maximum relative error is less than 10%, which indicates that the fracture strain prediction model of the cylindrical shell with waveform regulator established in this paper by considering the increase of elastic energy per unit volume caused by stress concentration on the shell is reliable.

控制波形调节器是一种通过单点爆轰实现多源爆震波叠加的方法。该方法不需要削弱壳体的强度，而是依靠叠加产生的高应力将壳体切割成规则的碎片。此外，它可以与不同的起始方法相结合，以改变破碎结果。本研究针对带波形调节器的炸药装药驱动金属圆柱壳的断裂应变，首先采用理论分析方法，得到了带波形调节器的圆柱壳断裂应变预测模型和应力集中因子的轴向分布模型。在此基础上，采用理论分析和数值模型相结合的方法研究了波形调节器对破片初速度的影响。最后，通过实验对带波形调节器的圆柱壳断裂应变预测模型进行了验证。研究结果表明，爆震波在不同轴向位置的碰撞角度不同，导致壳体上的应力集中系数沿轴向呈现先逐渐减小后急剧增大再迅速减小的趋势。此外，槽距和外装药厚度的变化也会影响应力集中系数，其中外装药厚度的影响比较大。装药体积与波形调节器体积之比越小，轴向稀疏波强度越大，破片初速度减小越大。从起裂端到非起裂端，壳的破坏模式依次由纯剪切、拉剪混合破坏、最后到纯拉伸破坏。实验结果与断裂应变模型的计算结果吻合较好，最大相对误差小于10%，表明本文建立的考虑壳体应力集中引起的单位体积弹性能增加的带波形调节器圆柱壳断裂应变预测模型是可靠的。

{"title":"Dynamic response characteristics of metal cylindrical shell driven by explosive charge with waveform regulator","authors":"Weixin Bi , Weibing Li , Junbao Li , Heyang Xu , Wenbin Li","doi":"10.1016/j.dt.2025.05.015","DOIUrl":"10.1016/j.dt.2025.05.015","url":null,"abstract":"<div><div>Waveform regulator in charge is a method that can realize multi-source detonation wave superposition through a single point detonation. The method does not need to weaken the strength of shell, and relies on the high stress generated by superposition to cut shell into regular fragments. Additionally, it can be combined with different initiation methods to alter the fragmentation outcomes. In this study, aiming at the fracture strain of metal cylindrical shell driven by explosive charge with waveform regulator, theoretical analysis was first adopted to obtain the prediction model of the fracture strain of cylindrical shell with waveform regulator and the model of the axial distribution of the stress concentration factor. On this basis, both theoretical analysis and numerical models were utilized to investigate the effect of waveform regulator on the initial velocity of fragments. Finally, experiments were conducted to validate the fracture strain prediction model for cylindrical shell with waveform regulator. The research results show that the collision angles of the detonation waves at different axial positions are different, which leads to the stress concentration factor on the shell presenting a trend of gradually decreasing, then sharply increasing, and then rapidly decreasing along the axial direction. Additionally, the changes in the slot spacing and the thickness of outer charge will also affect the stress concentration factor, and the influence of outer charge thickness is relatively large. The smaller the ratio of charge volume to waveform regulator volume, the larger the axial sparse wave intensity and the more the fragment initial velocity decrease. From the initiation end to the non-initiation end, the failure modes of the shell sequentially change from pure shear, to mixed tensile-shear, and finally to pure tensile failure. The experimental results are in good agreement with the calculated results of the fracture strain model, and the maximum relative error is less than 10%, which indicates that the fracture strain prediction model of the cylindrical shell with waveform regulator established in this paper by considering the increase of elastic energy per unit volume caused by stress concentration on the shell is reliable.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"52 ","pages":"Pages 84-99"},"PeriodicalIF":5.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145278353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Historical trajectory, current status, and future challenges of powder engines and propellant supply technologies: A comprehensive review 粉末发动机和推进剂供应技术的历史轨迹、现状和未来挑战：综合综述

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-10-01 DOI: 10.1016/j.dt.2025.06.005

Guanlong Ren , Haijun Sun , Chunbo Hu , Yuxin Yang , Chao Li , Yihua Xu , Rui Xue , Xiaoan Hu

Powder engine as a novel type of engine using high-energy metal powder as fuel and gas, liquid, or solid as oxidizer. These engines exhibit remarkable adaptability, flexible thrust regulation, and multi-pulse start-stop, which have significant application potentials in the fields of near-Earth space development, space propulsion systems, and deep-sea exploration. The scope of this review encompasses the classification and application of powder engines, the classification of powdered fuel supply systems, and the prospective trajectories and pivotal challenges of powder engines and fuel supply technologies. This work points out that although certain ground-based experimental challenges on powder engines have been solved, the relative technology remains in the nascent stages of feasibility demonstration and testing. The pneumatic and motor-driven piston methods currently dominate as the primary means for supplying fuel, and the structure of the piston and intake should be further optimized in the future to promote fuel fluidization and delivery efficiency. The adaptability of powder engines and powdered fuels under different pre-treatment and loading methods should be evaluated. Furthermore, the stability of powdered fuel delivery across varying operational environments, the accuracy of CFD modeling, and the precision of mass flow rate measurement and prediction technologies necessitate further enhancement and refinement. These advancements are crucial for the maturation of powder engine technology and its integration into practical applications.

粉末发动机是一种以高能金属粉末为燃料，以气体、液体或固体为氧化剂的新型发动机。该发动机具有良好的适应性、灵活的推力调节和多脉冲启停能力，在近地空间开发、空间推进系统和深海探测等领域具有重要的应用潜力。本文综述了粉末发动机的分类和应用，粉末燃料供应系统的分类，粉末发动机和燃料供应技术的发展趋势和关键挑战。这项工作指出，虽然粉末发动机的一些地面实验挑战已经解决，但相关技术仍处于可行性论证和测试的初级阶段。目前，气动和马达驱动活塞方式是供油的主要方式，未来应进一步优化活塞和进气结构，以促进燃料流化和输送效率。对粉末发动机和粉末燃料在不同预处理和装载方式下的适应性进行评估。此外，粉末燃料在不同操作环境下输送的稳定性、CFD建模的准确性以及质量流量测量和预测技术的精度都需要进一步增强和改进。这些进步对粉末发动机技术的成熟和实际应用具有重要意义。

{"title":"Historical trajectory, current status, and future challenges of powder engines and propellant supply technologies: A comprehensive review","authors":"Guanlong Ren , Haijun Sun , Chunbo Hu , Yuxin Yang , Chao Li , Yihua Xu , Rui Xue , Xiaoan Hu","doi":"10.1016/j.dt.2025.06.005","DOIUrl":"10.1016/j.dt.2025.06.005","url":null,"abstract":"<div><div>Powder engine as a novel type of engine using high-energy metal powder as fuel and gas, liquid, or solid as oxidizer. These engines exhibit remarkable adaptability, flexible thrust regulation, and multi-pulse start-stop, which have significant application potentials in the fields of near-Earth space development, space propulsion systems, and deep-sea exploration. The scope of this review encompasses the classification and application of powder engines, the classification of powdered fuel supply systems, and the prospective trajectories and pivotal challenges of powder engines and fuel supply technologies. This work points out that although certain ground-based experimental challenges on powder engines have been solved, the relative technology remains in the nascent stages of feasibility demonstration and testing. The pneumatic and motor-driven piston methods currently dominate as the primary means for supplying fuel, and the structure of the piston and intake should be further optimized in the future to promote fuel fluidization and delivery efficiency. The adaptability of powder engines and powdered fuels under different pre-treatment and loading methods should be evaluated. Furthermore, the stability of powdered fuel delivery across varying operational environments, the accuracy of CFD modeling, and the precision of mass flow rate measurement and prediction technologies necessitate further enhancement and refinement. These advancements are crucial for the maturation of powder engine technology and its integration into practical applications.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"52 ","pages":"Pages 142-183"},"PeriodicalIF":5.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145278357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical analysis of a vented methane/air explosion in a large-scale chamber 大型燃烧室甲烷/空气排气爆炸的数值分析

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-10-01 DOI: 10.1016/j.dt.2025.05.021

Huadao Xing , Guangan Xu , Yanyu Qiu , Song Sun , Bin Li , Mingyang Wang , Lifeng Xie

The internal and external flow fields during vented explosions of methane were characterized through numerical simulation, and the capability of numerical simulation thereof was validated by previous experimental data at three ignition positions. The venting mechanism was revealed by the simulated concentration distribution, temperature profile, and airflow velocity. The results show rear ignition results in the external methane mass distribution taking the form of "mushroom" and columnar flames in the external space, which can be expressed as a third-order polynomial relationship with distance; central ignition forms a relationship of the form y = Ax^B. Front ignition causes the temperature to show a tendency to repeated oscillations (rising, falling, and rising). Central ignition generates the maximum vented airflow velocity (V_max = 320 m/s) upon vent opening. The results indicate that it is acceptable to apply numerical simulation of methane explosions in practice.

通过数值模拟对甲烷喷放爆炸的内外流场进行了表征，并通过已有的三个点火位置的实验数据验证了数值模拟的能力。模拟的浓度分布、温度分布和气流速度揭示了排气机理。结果表明：后点燃导致外置甲烷质量分布呈“蘑菇”状，外置空间呈柱状火焰分布，与距离呈三阶多项式关系；中心点火形成y = AxB形式的关系。前点火使温度显示出反复振荡的趋势（上升、下降和上升）。中心点火在通风口开启时产生最大排气速度（Vmax = 320 m/s）。结果表明，将数值模拟应用于实际工作中是可以接受的。

引用次数: 0

Accurate prediction of blast-induced ground vibration intensity using optimized machine learning models 利用优化的机器学习模型准确预测爆炸引起的地面振动强度

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-10-01 DOI: 10.1016/j.dt.2025.06.019

Lihua Chen , Yewuhalashet Fissha , Mahdi Hasanipanah , Refka Ghodhbani , Hesam Dehghani , Jitendra Khatti

Blast-induced ground vibration, quantified by peak particle velocity (PPV), is a crucial factor in mitigating environmental and structural risks in mining and geotechnical engineering. Accurate PPV prediction facilitates safer and more sustainable blasting operations by minimizing adverse impacts and ensuring regulatory compliance. This study presents an advanced predictive framework integrating CatBoost (CB) with nature-inspired optimization algorithms, including the Bat Algorithm (BAT), Sparrow Search Algorithm (SSA), Butterfly Optimization Algorithm (BOA), and Grasshopper Optimization Algorithm (GOA). A comprehensive dataset from the Sarcheshmeh Copper Mine in Iran was utilized to develop and evaluate these models using key performance metrics such as the Index of Agreement (IoA), Nash-Sutcliffe Efficiency (NSE), and the coefficient of determination (R²). The hybrid CB-BOA model outperformed other approaches, achieving the highest accuracy (R² = 0.989) and the lowest prediction errors. SHAP analysis identified Distance (Di) as the most influential variable affecting PPV, while uncertainty analysis confirmed CB-BOA as the most reliable model, featuring the narrowest prediction interval. These findings highlight the effectiveness of hybrid machine learning models in refining PPV predictions, contributing to improved blast design strategies, enhanced structural safety, and reduced environmental impacts in mining and geotechnical engineering.

在矿山和岩土工程中，由峰值颗粒速度（PPV）量化的爆破引起的地面振动是降低环境和结构风险的关键因素。准确的PPV预测通过最大限度地减少不利影响和确保法规遵从性，促进更安全、更可持续的爆破作业。本研究提出了一种先进的预测框架，将CatBoost （CB）与蝙蝠算法（Bat）、麻雀搜索算法（SSA）、蝴蝶优化算法（BOA）和蚱蜢优化算法（GOA）等自然优化算法相结合。利用来自伊朗Sarcheshmeh铜矿的综合数据集，使用关键绩效指标(如协议指数（IoA）、纳什-苏特克利夫效率（NSE）和决定系数（R2）来开发和评估这些模型。混合CB-BOA模型的预测准确率最高（R2 = 0.989），预测误差最低。SHAP分析认为Distance （Di）是影响PPV最大的变量，不确定性分析认为CB-BOA是最可靠的模型，预测区间最窄。这些发现突出了混合机器学习模型在改进PPV预测方面的有效性，有助于改进爆炸设计策略，提高结构安全性，减少采矿和岩土工程中的环境影响。

{"title":"Accurate prediction of blast-induced ground vibration intensity using optimized machine learning models","authors":"Lihua Chen , Yewuhalashet Fissha , Mahdi Hasanipanah , Refka Ghodhbani , Hesam Dehghani , Jitendra Khatti","doi":"10.1016/j.dt.2025.06.019","DOIUrl":"10.1016/j.dt.2025.06.019","url":null,"abstract":"<div><div>Blast-induced ground vibration, quantified by peak particle velocity (PPV), is a crucial factor in mitigating environmental and structural risks in mining and geotechnical engineering. Accurate PPV prediction facilitates safer and more sustainable blasting operations by minimizing adverse impacts and ensuring regulatory compliance. This study presents an advanced predictive framework integrating CatBoost (CB) with nature-inspired optimization algorithms, including the Bat Algorithm (BAT), Sparrow Search Algorithm (SSA), Butterfly Optimization Algorithm (BOA), and Grasshopper Optimization Algorithm (GOA). A comprehensive dataset from the Sarcheshmeh Copper Mine in Iran was utilized to develop and evaluate these models using key performance metrics such as the Index of Agreement (IoA), Nash-Sutcliffe Efficiency (NSE), and the coefficient of determination (R<sup>2</sup>). The hybrid CB-BOA model outperformed other approaches, achieving the highest accuracy (R<sup>2</sup> = 0.989) and the lowest prediction errors. SHAP analysis identified Distance (Di) as the most influential variable affecting PPV, while uncertainty analysis confirmed CB-BOA as the most reliable model, featuring the narrowest prediction interval. These findings highlight the effectiveness of hybrid machine learning models in refining PPV predictions, contributing to improved blast design strategies, enhanced structural safety, and reduced environmental impacts in mining and geotechnical engineering.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"52 ","pages":"Pages 32-46"},"PeriodicalIF":5.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145277876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Discovery of energetic-energetic cocrystal polymorphs with high-energy, low-sensitivity 发现高能量、低灵敏度的高能共晶多晶

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-09-01 DOI: 10.1016/j.dt.2025.05.026

Shen Qiao , Yanwei Tan , Zening Liu , Fan Ma , Shi Huang , Kangcai Wang , Yu Liu , Zongwei Yang

Herein, a first example of energetic-energetic cocrystal polymorphs with a 1:1 M ratio was discovered by cocrystallizing CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) with 1,3-DNP (1,3-dinitropyrazole). These two energetic cocrystal polymorphs (cocrystal 1 and cocrystal 2) exhibit distinct crystal packing styles, which lead to significant variations in their physicochemical properties. Notably, cocrystal 2 has a high density of 1.963 g⋅cm⁻³ at 170 K, exhibiting high detonation performances (9187 m⋅s⁻¹; 38.68 GPa) comparable to HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane) meanwhile displaying an improved safety (10 J) relative to RDX (1,3,5-trinitro-1,3,5-triazinane), making it a potential high-energy, low-sensitivity energetic material. This work opens up a new strategy to deeply tune properties of energetic materials by constructing energetic-energetic cocrystal polymorphs. These energetic cocrystal polymorphs represent a new field of energetic materials that has not yet been studied.

本文通过与1,3- dnp（1,3-二硝基吡唑）共晶，首次发现了M比为1:1的能量-能共晶多晶。这两种高能共晶多晶（共晶1和共晶2）表现出不同的晶体填充方式，这导致了它们的物理化学性质的显著变化。值得注意的是，共晶2在170 K下具有1.963 g⋅cm−3的高密度，具有与HMX（1,3,5,7-四硝基-1,3,5,7-四氮杂烷）相当的高爆轰性能（9187 m⋅s−1;38.68 GPa），同时具有比RDX（1,3,5-三硝基-1,3,5-三氮杂烷）更高的安全性（10 J），是一种潜在的高能量、低灵敏度能材料。这项工作开辟了一种新的策略，通过构建能量-能量共晶多晶来深度调整含能材料的性质。这些高能共晶多晶体代表了一个尚未被研究的高能材料新领域。

{"title":"Discovery of energetic-energetic cocrystal polymorphs with high-energy, low-sensitivity","authors":"Shen Qiao , Yanwei Tan , Zening Liu , Fan Ma , Shi Huang , Kangcai Wang , Yu Liu , Zongwei Yang","doi":"10.1016/j.dt.2025.05.026","DOIUrl":"10.1016/j.dt.2025.05.026","url":null,"abstract":"<div><div>Herein, a first example of energetic-energetic cocrystal polymorphs with a 1:1 M ratio was discovered by cocrystallizing CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) with 1,3-DNP (1,3-dinitropyrazole). These two energetic cocrystal polymorphs (cocrystal <strong>1</strong> and cocrystal <strong>2</strong>) exhibit distinct crystal packing styles, which lead to significant variations in their physicochemical properties. Notably, cocrystal <strong>2</strong> has a high density of 1.963 g⋅cm<sup>−3</sup> at 170 K, exhibiting high detonation performances (9187 m⋅s<sup>−1</sup>; 38.68 GPa) comparable to HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane) meanwhile displaying an improved safety (10 J) relative to RDX (1,3,5-trinitro-1,3,5-triazinane), making it a potential high-energy, low-sensitivity energetic material. This work opens up a new strategy to deeply tune properties of energetic materials by constructing energetic-energetic cocrystal polymorphs. These energetic cocrystal polymorphs represent a new field of energetic materials that has not yet been studied.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"51 ","pages":"Pages 127-133"},"PeriodicalIF":5.9,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bismuth's role in quaternary thulium doped tellurite glasses: Achieving optical clarity and radiation shielding 铋在掺季铥碲酸盐玻璃中的作用：实现光学清晰度和辐射屏蔽

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-09-01 DOI: 10.1016/j.dt.2025.05.006

N.A.M. Rusni , N.A. Abdul-Manaf , N. Ahmad , L. Hasnimulyati , W.Y.W. Yusoff , A. Azuraida

This study explores the impact of bismuth oxide (Bi₂O₃) on the optical and radiation shielding properties of transparent, lead-free thulium-doped bismuth borotellurite radiation shielding glass. The investigated glass composition follows the formula [(TeO₂)₇₅ (B₂O₃)₂₅]_98-x (Bi₂O₃)_x [Tm₂O₃]₂, where x = 0 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, and 30 mol%. All glass samples remain transparent, with an optical bandgap (

E_{opt}

) exceeding 3.1 eV, ensuring visible light transmission. Radiation shielding data from Phy-X and XCom reveal interactions of the photoelectric effect, Compton scattering, and pair production, with minimal relative difference in mass attenuation coefficient (

MAC

) which is between 0.05 and 0.56. At 0.662 MeV photon energy, the 20 mol% and 25 mol% Bi₂O₃ glasses exhibit significantly higher Phy-X

M A C

values than other samples, except RS 520 glass, which contains 71% PbO. Despite incorporating only up to 25 mol% Bi₂O₃, these glasses outperform others in density, half-value layer (

HVL

), and mean free path (

MFP

). Correlating

E_{opt}

and

MAC

, the 20 mol% Bi₂O₃ glass is the best candidate for transparent radiation shielding glass due to its wide optical bandgap which prevents ionization of trapped holes. Significantly, the linkage between

MFP

and molar refraction was also discovered based on the particle size influence on both parameters.

本研究探讨了氧化铋（Bi2O3）对透明无铅掺铥硼碲酸铋辐射屏蔽玻璃光学和辐射屏蔽性能的影响。所研究的玻璃组合物遵循公式[(TeO2)75 (B2O3)25]98-x (Bi2O3)x [Tm2O3]2，其中x = 0 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%， 25 mol%和30 mol%。所有玻璃样品保持透明，光学带隙（Eopt）超过3.1 eV，确保可见光透射。来自Phy-X和XCom的辐射屏蔽数据揭示了光电效应、康普顿散射和对产生的相互作用，质量衰减系数（MAC）的相对差异很小，在0.05 ~ 0.56之间。在0.662 MeV光子能量下，20 mol%和25 mol% Bi2O3玻璃的Phy-X MAC值明显高于其他样品，但RS 520玻璃的PbO含量为71%。尽管这些玻璃的Bi2O3含量只有25 mol%，但它们在密度、半值层（HVL）和平均自由程（MFP）方面都优于其他玻璃。对比Eopt和MAC， 20 mol% Bi2O3玻璃是透明辐射屏蔽玻璃的最佳候选材料，因为它具有宽的光学带隙，可以防止被困空穴的电离。值得注意的是，基于粒径对这两个参数的影响，还发现了MFP和摩尔折射之间的联系。

{"title":"Bismuth's role in quaternary thulium doped tellurite glasses: Achieving optical clarity and radiation shielding","authors":"N.A.M. Rusni , N.A. Abdul-Manaf , N. Ahmad , L. Hasnimulyati , W.Y.W. Yusoff , A. Azuraida","doi":"10.1016/j.dt.2025.05.006","DOIUrl":"10.1016/j.dt.2025.05.006","url":null,"abstract":"<div><div>This study explores the impact of bismuth oxide (Bi<sub>2</sub>O<sub>3</sub>) on the optical and radiation shielding properties of transparent, lead-free thulium-doped bismuth borotellurite radiation shielding glass. The investigated glass composition follows the formula [(TeO<sub>2</sub>)<sub>75</sub> (B<sub>2</sub>O<sub>3</sub>)<sub>25</sub>]<sub>98-<em>x</em></sub> (Bi<sub>2</sub>O<sub>3</sub>)<sub><em>x</em></sub> [Tm<sub>2</sub>O<sub>3</sub>]<sub>2</sub>, where <em>x</em> = 0 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, and 30 mol%. All glass samples remain transparent, with an optical bandgap (<span><math><mrow><msub><mi>E</mi><mtext>opt</mtext></msub></mrow></math></span>) exceeding 3.1 eV, ensuring visible light transmission. Radiation shielding data from Phy-X and XCom reveal interactions of the photoelectric effect, Compton scattering, and pair production, with minimal relative difference in mass attenuation coefficient (<span><math><mrow><mtext>MAC</mtext></mrow></math></span>) which is between 0.05 and 0.56. At 0.662 MeV photon energy, the 20 mol% and 25 mol% Bi<sub>2</sub>O<sub>3</sub> glasses exhibit significantly higher Phy-X <span><math><mrow><mi>M</mi><mi>A</mi><mi>C</mi></mrow></math></span> values than other samples, except RS 520 glass, which contains 71% PbO. Despite incorporating only up to 25 mol% Bi<sub>2</sub>O<sub>3</sub>, these glasses outperform others in density, half-value layer (<span><math><mrow><mtext>HVL</mtext></mrow></math></span>), and mean free path (<span><math><mrow><mtext>MFP</mtext></mrow></math></span>). Correlating <span><math><mrow><msub><mi>E</mi><mtext>opt</mtext></msub></mrow></math></span> and <span><math><mrow><mtext>MAC</mtext></mrow></math></span>, the 20 mol% Bi<sub>2</sub>O<sub>3</sub> glass is the best candidate for transparent radiation shielding glass due to its wide optical bandgap which prevents ionization of trapped holes. Significantly, the linkage between <span><math><mrow><mtext>MFP</mtext></mrow></math></span> and molar refraction was also discovered based on the particle size influence on both parameters.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"51 ","pages":"Pages 134-144"},"PeriodicalIF":5.9,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Variable reward function-driven strategies for impulsive orbital attack-defense games under multiple constraints and victory conditions 多约束和多胜利条件下脉冲轨道攻防博弈的可变奖励函数驱动策略

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-09-01 DOI: 10.1016/j.dt.2025.05.002

Liran Zhao, Sihan Xu, Qinbo Sun, Zhaohui Dang

This paper investigates impulsive orbital attack-defense (AD) games under multiple constraints and victory conditions, involving three spacecraft: attacker, target, and defender. In the AD scenario, the attacker aims to breach the defender's interception to rendezvous with the target, while the defender seeks to protect the target by blocking or actively pursuing the attacker. Four different maneuvering constraints and five potential game outcomes are incorporated to more accurately model AD game problems and increase complexity, thereby reducing the effectiveness of traditional methods such as differential games and game-tree searches. To address these challenges, this study proposes a multi-agent deep reinforcement learning solution with variable reward functions. Two attack strategies, Direct attack (DA) and Bypass attack (BA), are developed for the attacker, each focusing on different mission priorities. Similarly, two defense strategies, Direct interdiction (DI) and Collinear interdiction (CI), are designed for the defender, each optimizing specific defensive actions through tailored reward functions. Each reward function incorporates both process rewards (e.g., distance and angle) and outcome rewards, derived from physical principles and validated via geometric analysis. Extensive simulations of four strategy confrontations demonstrate average defensive success rates of 75% for DI vs. DA, 40% for DI vs. BA, 80% for CI vs. DA, and 70% for CI vs. BA. Results indicate that CI outperforms DI for defenders, while BA outperforms DA for attackers. Moreover, defenders achieve their objectives more effectively under identical maneuvering capabilities. Trajectory evolution analyses further illustrate the effectiveness of the proposed variable reward function-driven strategies. These strategies and analyses offer valuable guidance for practical orbital defense scenarios and lay a foundation for future multi-agent game research.

研究了多约束和多胜利条件下的脉冲轨道攻防博弈问题，涉及攻击者、目标和防御者三个航天器。在AD场景中，攻击者的目的是突破防御者的拦截与目标会合，防御者的目的是通过阻挡或主动追击攻击者来保护目标。将四种不同的机动约束和五种潜在的博弈结果结合起来，更准确地模拟AD博弈问题并增加复杂性，从而降低了差分博弈和博弈树搜索等传统方法的有效性。为了解决这些挑战，本研究提出了一种具有可变奖励函数的多智能体深度强化学习解决方案。针对攻击者提出了直接攻击（DA）和旁路攻击（BA）两种攻击策略，分别针对不同的任务优先级。同样，针对防御方设计了直接阻断（DI）和共线阻断（CI）两种防御策略，每种策略都通过量身定制的奖励函数来优化特定的防御行为。每个奖励函数都包含过程奖励（如距离和角度）和结果奖励，这些奖励源自物理原理并通过几何分析得到验证。四种策略对抗的广泛模拟表明，DI对DA的平均防御成功率为75%，DI对BA的平均防御成功率为40%，CI对DA的平均防御成功率为80%，CI对BA的平均防御成功率为70%。结果表明，对于防御者来说，CI优于DI，而对于攻击者来说，BA优于DA。此外，在相同的机动能力下，防御者更有效地实现其目标。轨迹演化分析进一步说明了所提出的可变奖励函数驱动策略的有效性。这些策略和分析为实际的轨道防御场景提供了有价值的指导，为未来的多智能体博弈研究奠定了基础。

{"title":"Variable reward function-driven strategies for impulsive orbital attack-defense games under multiple constraints and victory conditions","authors":"Liran Zhao, Sihan Xu, Qinbo Sun, Zhaohui Dang","doi":"10.1016/j.dt.2025.05.002","DOIUrl":"10.1016/j.dt.2025.05.002","url":null,"abstract":"<div><div>This paper investigates impulsive orbital attack-defense (AD) games under multiple constraints and victory conditions, involving three spacecraft: attacker, target, and defender. In the AD scenario, the attacker aims to breach the defender's interception to rendezvous with the target, while the defender seeks to protect the target by blocking or actively pursuing the attacker. Four different maneuvering constraints and five potential game outcomes are incorporated to more accurately model AD game problems and increase complexity, thereby reducing the effectiveness of traditional methods such as differential games and game-tree searches. To address these challenges, this study proposes a multi-agent deep reinforcement learning solution with variable reward functions. Two attack strategies, Direct attack (DA) and Bypass attack (BA), are developed for the attacker, each focusing on different mission priorities. Similarly, two defense strategies, Direct interdiction (DI) and Collinear interdiction (CI), are designed for the defender, each optimizing specific defensive actions through tailored reward functions. Each reward function incorporates both process rewards (e.g., distance and angle) and outcome rewards, derived from physical principles and validated via geometric analysis. Extensive simulations of four strategy confrontations demonstrate average defensive success rates of 75% for DI vs. DA, 40% for DI vs. BA, 80% for CI vs. DA, and 70% for CI vs. BA. Results indicate that CI outperforms DI for defenders, while BA outperforms DA for attackers. Moreover, defenders achieve their objectives more effectively under identical maneuvering capabilities. Trajectory evolution analyses further illustrate the effectiveness of the proposed variable reward function-driven strategies. These strategies and analyses offer valuable guidance for practical orbital defense scenarios and lay a foundation for future multi-agent game research.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"51 ","pages":"Pages 159-183"},"PeriodicalIF":5.9,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145098506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A review of current studies on the unmanned aerial vehicle-based moving target tracking methods 综述了基于无人机的运动目标跟踪方法的研究现状

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-09-01 DOI: 10.1016/j.dt.2025.01.013

Binbin Yan , Yuxin Wei , Shuangxi Liu , Wei Huang , Ruizhe Feng , Xiaoqian Chen

Unmanned aerial vehicles (UAVs) have become crucial tools in moving target tracking due to their agility and ability to operate in complex, dynamic environments. UAVs must meet several requirements to achieve stable tracking, including maintaining continuous target visibility amidst occlusions, ensuring flight safety, and achieving smooth trajectory planning. This paper reviews the latest advancements in UAV-based target tracking, highlighting information prediction, tracking strategies, and swarm cooperation. To address challenges including target visibility and occlusion, real-time prediction and tracking in dynamic environments, flight safety and coordination, resource management and energy efficiency, the paper identifies future research directions aimed at improving the performance, reliability, and scalability of UAV tracking system.

由于无人机的敏捷性和在复杂、动态环境中运行的能力，它已成为移动目标跟踪的重要工具。为了实现稳定的跟踪，无人机必须满足几个要求，包括在遮挡中保持目标的连续可见性、确保飞行安全以及实现平滑的轨迹规划。本文综述了基于无人机的目标跟踪的最新进展，重点介绍了信息预测、跟踪策略和群体协作。针对目标可见性与遮挡、动态环境下的实时预测与跟踪、飞行安全与协调、资源管理与能源效率等挑战，提出了提高无人机跟踪系统性能、可靠性和可扩展性的未来研究方向。

引用次数: 0

Mesoscopic analysis on projectile motion characteristics in oblique penetration into concrete 斜侵彻混凝土弹丸运动特性细观分析

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-09-01 DOI: 10.1016/j.dt.2025.05.001

Xiaoyu Li , Jie Zhang , Yu Rong , Zhihua Wang

The motion characteristics of projectile during oblique penetration into concrete were studied using a three-dimensional meso-scale model. The finite element model validation and parameter chosen were conducted by comparing the experimental data, with computational efficiency enhanced through improved mesh refinement. Penetration simulations involving deformable projectiles at various incident angles analyzed the effects of aggregate volume fraction and particle size on ballistic trajectory and terminal deflection. Sensitivity analysis reveals a strong power-law relationship between aggregate content and the projectile's deflection angle. The increase in aggregate content will enhance the confinement effect, shorten the intrusion distance of the projectile, and lead to a decrease in the deflection angle of the projectile. The effect of aggregate particle size on the projectile deflection angle follows a Gaussian distribution. The maximum deflection angle occurs when the aggregate particle size is between 2.7 and 3.1 times the projectile diameter. An increase in particle size reduces the number of aggregate-mortar interfaces at the same aggregate volume fraction, leading to an enlargement of the damage zone in concrete, a decrease in the number of cracks, and an increase in crack length. These findings enhance the understanding of concrete penetration mechanisms and offers valuable insights for engineering structure protection.

采用三维中尺度模型研究了弹丸斜侵彻混凝土过程中的运动特性。通过对比实验数据进行有限元模型验证和参数选择，通过改进网格细化提高计算效率。变形弹在不同入射角下的侵彻仿真分析了聚合体体积分数和颗粒尺寸对弹道和末端偏转的影响。灵敏度分析表明，聚类含量与弹丸偏角之间存在很强的幂律关系。骨料含量的增加会增强约束效果，缩短弹丸的侵入距离，导致弹丸的偏角减小。骨料粒径对弹丸偏转角的影响服从高斯分布。当集料粒径为弹体直径的2.7 ~ 3.1倍时，发生最大偏转角。在相同骨料体积分数下，粒径的增大减少了骨料-砂浆界面的数量，导致混凝土损伤区域的扩大，裂缝数量的减少，裂缝长度的增加。这些发现增强了对混凝土侵彻机理的认识，并为工程结构保护提供了有价值的见解。

{"title":"Mesoscopic analysis on projectile motion characteristics in oblique penetration into concrete","authors":"Xiaoyu Li , Jie Zhang , Yu Rong , Zhihua Wang","doi":"10.1016/j.dt.2025.05.001","DOIUrl":"10.1016/j.dt.2025.05.001","url":null,"abstract":"<div><div>The motion characteristics of projectile during oblique penetration into concrete were studied using a three-dimensional meso-scale model. The finite element model validation and parameter chosen were conducted by comparing the experimental data, with computational efficiency enhanced through improved mesh refinement. Penetration simulations involving deformable projectiles at various incident angles analyzed the effects of aggregate volume fraction and particle size on ballistic trajectory and terminal deflection. Sensitivity analysis reveals a strong power-law relationship between aggregate content and the projectile's deflection angle. The increase in aggregate content will enhance the confinement effect, shorten the intrusion distance of the projectile, and lead to a decrease in the deflection angle of the projectile. The effect of aggregate particle size on the projectile deflection angle follows a Gaussian distribution. The maximum deflection angle occurs when the aggregate particle size is between 2.7 and 3.1 times the projectile diameter. An increase in particle size reduces the number of aggregate-mortar interfaces at the same aggregate volume fraction, leading to an enlargement of the damage zone in concrete, a decrease in the number of cracks, and an increase in crack length. These findings enhance the understanding of concrete penetration mechanisms and offers valuable insights for engineering structure protection.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"51 ","pages":"Pages 220-233"},"PeriodicalIF":5.9,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145098556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0