The surface activation of boron to improve ignition and combustion characteristic

Boron is a very promising and highly attractive fuel because of high calorific value. However, the practical applications in explosives and propellants of boron have been limited by long ignition delay time and low combustion efficiency. Herein, nano-Al and graphene fluoride (GF) as surface activated materials are employed to coat boron (B) particles to improve ignition and combustion performance. The reaction heat of nano-Al coated B/KNO₃ and GF coated B/KNO₃ are 1116.83 J/g and 862.69 J/g, respectively, which are higher than that of pure B/KNO₃ (823.39 J/g). The ignition delay time of B/KNO₃ could be reduced through nano-Al coating. The shortest ignition delay time is only 75 ms for B coated with nano-Al of 8 wt%, which is much shorter than that of pure B/KNO₃ (109 ms). However, the ignition delay time of B/KNO₃ coated with GF has been increased from 109 to 187 ms. B coated with GF and nano-Al shown significantly influence on the pressure output and flame structure of B/KNO₃. Furthermore, the effects of B/O ratios on the pressure output and ignition delay time have been further fully studied. For B/KNO₃ coated with nano-Al and GF, the highest pressures are 88 KPa and 59 KPa for B/O ratio of 4:6, and the minimum ignition delay time are 94 ms and 148 ms for B/O ratio of 7:3. Based on the above results, the reaction process of boron coated with GF and nano-Al has been proposed to understand combustion mechanism.     

目标毁伤效果评估技术研究进展

目标毁伤效果评估作为目标保障的一项重要内容,对精确打击作战情报保障起到了核心作用,是现代精确打击体系的一个重要环节和关键步骤。文章从评估方法、评估模型和评估系统三个方面入手,梳理了国内外目标毁伤效果评估技术的最新研究进展,并对目前各类评估方法、模型及系统的优缺点分别进行了评述。最后,指出了该领域今后的研究方向。     

基于能源互联网背景的储能二次电池技术发展分析

能源互联网是在现有配电网基础上,融合新能源技术和互联网技术,将分布式能源采集装置和分布式能源储存装置联合发展起来的新技术,对于优化能源结构和提高能源利用具有重要的意义。文章以能源互联网对储能电池的需求为背景,首先归纳了能源互联网对于储能电池的要求,在此基础上重点分析了多种可应用于能源互联网的储能电池的性能与特点,并对其未来发展趋势进行了展望。     

基于改进萤火虫优化算法的BP神经网络目标群威胁判断

以舰艇防空作战目标选择决策和规划需求为背景,针对萤火虫算法求解精度不高且收敛速度较慢的问题,提出可动态调整步长的改进萤火虫优化算法。在改进萤火虫优化算法的基础上,建立基于改进萤火虫优化算法的BP神经网络目标群威胁判断结构模型。通过改进萤火虫算法优化BP神经网络的初始权值和阈值,能够更好地预测测试集。实验结果表明,该方法可快速、准确地实现目标群威胁判断。     

中段反导指挥控制能力生成机理及构成分析

提出了中段反导指挥控制能力生成的要素基础建设机理、要素集成聚优机理和要素联动涌效机理,构建了中段反导指挥控制能力总体构成框架,并对作战能力具体构成进行了分析,可为反导指挥控制系统建设及作战效能评估提供借鉴。     

美国陆军网络装备作战评估及启示

作战试验能有效地推动装备体系的建设发展,本文通过分析美国陆军网络集成评估与联合作战评估的作战试验特点,提出军队开展装备作战试验的几个建议。首先,总结了美国陆军网络集成评估到联合作战评估的发展演变,主要包括网络集成评估的地位和作用、网络集成评估的实施流程以及13次网络集成评估和3次作战评估的有关情况;其次,分析了网络集成评估的一系列作战试验特点,诸如实际作战需求牵引、逼真场景构建、试训一体化模式、部队战斗力的直接生成以及作战能力的军民融合式发展等;最后,提出了网络集成评估带来的若干启示,从满足实战能力需求开展作战试验、突出装备体系的互操作能力评估、探索试训结合的作战试验模式、组建专门的作战试验部队及鼓励工业部门参与作战试验等方面推动军队作战试验的发展。     

Damage assessment of the target area of the island/reef under the attack of missile warhead

Under the background of vigorously developing facilities of island/reef in the world, the economic value and strategic significance of the island/reef have become increasingly important. Unfortunately, they may easily become the attacking target of missiles in the war time. Therefore, aiming at the damage quantification of the targets in the island/reef under the missile attacking, a macroscopic damage assessment model for the target area is proposed in this paper. The model focuses on the construction of the assessment model framework. Firstly, the analytic hierarchy process and the grey relational analysis are applied to measure the importance of each target in the region through four indicators of the target hazard, striking urgency, damage advantage and mission relevance, respectively. Secondly, based on the damage mechanism of shock wave and fragments to target, the corresponding damage model is established, and the damage grade of each target in the evaluated area is obtained according to the damage criteria and grading standard. Finally, the model obtains the overall damage grade of the target area by employing the fuzzy comprehensive evaluation method, with synthesizing the importance and the damage grade of each target. Through the verification of an example, it demonstrates the certain feasibility of the model and provides a certain basis and reference for the subsequent research.     

A novel variable topology design for a multi-flexible ejection mechanism

The airborne missile launch mechanism often subjects to significant deformations induced by the large ejection force during high-speed actuations in missile ejection process, leading to a substantial deviation of separation parameters from designed values that threats safety of the carrier. This study proposes a novel variable topology design for launch mechanism, achieved via a Prismatic-Revolute-Revolute pair (PR-R) motion formed by the structural gap with a specific direction. It enables launch mechanism variability during missile ejection process and optimizes the ejection force given by the front and back ejection arms, and greatly optimizes the separation parameters during missile ejection. The kinetics simulation analysis is conducted under working conditions of the original ejection mechanism and the novel mechanism with variable topology design, respectively. The results show that the novel variable topology design is more befitting for the launch process in terms of system safety and controllability, effectively improving the separation posture, restraining the flexible effect of the mechanism, and fulfilling the effectiveness of the design value of multi-rigid body.     

纤维缠绕复合材料夹芯圆柱体高应变率压缩吸能机理

为研究纤维缠绕复合材料夹芯圆柱体吸能元件在高应变率冲击压缩载荷作用下的变形损伤模式和能量吸收机理,采用ABAQUS商用有限元软件和分离式Hopkinson压杆装置开展数值模拟分析和试验验证研究。对比分析宏观力学响应规律和微观损伤破坏机理,可知吸能结构元件在高应变率压缩载荷下的力学响应具有典型的弹塑性特征,内部芯材主要产生压缩塑性损伤,而表层复合材料沿环向产生拉伸断裂破坏。研究表明,该吸能元件冲击压缩吸能特性优异,可满足水下结构平台的冲击防护和浮力储备要求。     

An attacker‐defender model for analyzing the vulnerability of initial attack in wildfire suppression

Wildfire managers use initial attack (IA) to control wildfires before they grow large and become difficult to suppress. Although the majority of wildfire incidents are contained by IA, the small percentage of fires that escape IA causes most of the damage. Therefore, planning a successful IA is very important. In this article, we study the vulnerability of IA in wildfire suppression using an attacker‐defender Stackelberg model. The attacker's objective is to coordinate the simultaneous ignition of fires at various points in a landscape to maximize the number of fires that cannot be contained by IA. The defender's objective is to optimally dispatch suppression resources from multiple fire stations located across the landscape to minimize the number of wildfires not contained by IA. We use a decomposition algorithm to solve the model and apply the model on a test case landscape. We also investigate the impact of delay in the response, the fire growth rate, the amount of suppression resources, and the locations of fire stations on the success of IA.