Damage of multi-layer spaced metallic target plates impacted by radial layered PELE

Three different kinds of PELE (the penetrator with lateral efficiency) were launched by ballistic artillery to impact the multi-layer spaced metal target plates. The impact velocities of the projectiles were measured by the velocity measuring system. The damage degree and process of each layer of target plate impacted by the three kinds of projectiles were analyzed. The experimental results show that all the three kinds of projectiles have the effect of expanding holes on the multi-layer spaced metal target plates. For the normal structure PELE(without layered) with tungsten alloy jacket and the radial layered PELE with tungsten alloy jacket, the diameters of holes on the second layer of plates are 3.36 times and 3.76 times of the diameter of the projectile, respectively. For radial layered PELE with W/Zr-based amorphous composite jacket, due to the large number of tungsten wires dispersed after the impact, the diameter of the holes on the four-layer spaced plates can reach 2.4 times, 3.04 times, 5.36 times and 2.68 times of the diameter of the projectile. Besides, the normal structure PELE with tungsten alloy jacket and the radial layered PELE whit tungsten alloy jacket formed a large number of fragments impact marks on the third target plate. Although the number of fragments penetrating the third target plate is not as large as that of the normal structure PELE, the area of dispersion of fragments impact craters on the third target plate is larger by the radial layered PELE. The radial layered PELE with W/Zr-based amorphous composite jacket released a lot of heat energy due to the impact of the matrix material, and formed a large area of ablation marks on the last three target plates.     

Military Off the Shelf Procurements: A Norwegian Case Study

Buying off the shelf procurements (OTS) has become an important part of the national acquisition strategy in several countries, and this paper seeks to bring empirical evidence on OTS as the preferred acquisition strategy by use of data from 2015 to 2022 investment portfolio of the Norwegian Armed Forces. We develop definitions for three categories of procurement – OTS, modified OTS and development projects – as well as a method to classify projects into these categories. Our first finding is that the characteristics of OTS projects correspond to modified OTS and development projects. Our second finding indicates that OTS projects perform better when it comes to the completion of projects according to the initial schedule, compared to development projects.     

目标宽频带RCS的快速算法研究

目标宽带RCS预估算法一直是计算电磁学的一个研究热点,本文分别研究了渐近波形估计技术（AWE）与最佳一致逼近技术在宽频带RCS预估领域内的应用。首先,介绍了传统矩量法计算RCS的原理,并分析了两种快速算法的计算过程。然后,采用这两种技术,分别计算了简易飞机模型的RCS值,并对这两种方法进行比较。计算结果表明相比传统的矩量法,这两种方法在不影响精度的前提下大大提高了计算效率。同时,相比渐近波形估计技术,最佳一致逼近技术在节省内存,节约时间方面更具优势。最后,采用最佳一致逼近理论,结合电磁计算软件,实现较大尺寸目标的宽频带RCS的计算。     

北斗系统新民用导航电文历书参数算法与性能分析

研究新公布的北斗民用导航电文中的两类历书与北斗二号导航电文历书的差异,对比分析各类历书对接收机首次定位时间的影响。利用实际的历书数据,比较不同历书类型的用户算法,分析不同龄期数据对接收机首次定位性能的影响。结果表明,高精度历书在1周的数据龄期内性能较为稳定,中等精度历书精度稍逊于高精度历书,但由于简化了电文空间,能接近高精度历书性能。简约历书进一步简化了参数数目和电文空间,尽管位置误差达到了数百千米,但却能在数月之后保持相应精度,有利于缩短接收机首次定位时间。     

基于多视角的装备体系军事需求开发框架模型

装备体系军事需求开发框架模型为装备体系军事需求的开发提供了指导和规则.考虑到军事装备体系自身的体系复杂性和参与军事需求开发的人员多样性,为了能综合反映出各个角度上的需求,应用多视角方法首先对装备体系军事需求进行了分析,然后基于该方法构建了军事需求开发框架模型,进而分析了装备体系军事需求体系,最后以示例来说明该框架模型的实用性.     

铝导线短路熔珠对固体可燃物引燃能力实验研究

在模拟试验平台上进行了铝导线短路熔珠引燃棉布、聚氨酯泡沫塑料和纸张的试验,得到了不同材料的临界加栽电压值和引燃规律。初步分析了加栽电压与短路熔珠粒径及引燃能力的关系。结果表明,随着短路电压增大,导线熔珠的粒径逐渐增大,熔珠对固体材料的引燃能力逐渐增强,氧指数越低、表面粗糙、易蓄热的材料越容易被点燃。棉布、聚氨酯泡沫塑料和纸屑被引燃的短路临界电压分别为50V、35V和45V。     

公安现役部队基层干部考核工作存在的问题与对策

公安现役部队基层干部考核工作是选准用好干部的关键环节。目前一些单位在基层干部考核工作中还存在着考核制度不健全、考核标准不科学、考核方法和形式简单等问题。加强和改进基层干部考核工作,必须端正基层干部考核工作的认识和观念,健全基层干部考核的制度,完善基层干部考核的标准,改进基层干部考核的方式方法。     

境外换持证件取道偷渡的形式特点及对策研究

境外换持证件取道偷渡活动由于检查难、处罚难而成为近年来犯罪分子偷渡的主要方式,严重损害了我国的国际声誉和形象,扰乱了正常的出入境秩序,对此必须有针对性地采取综合措施,才能收到最佳打击、防范效果。     

试论联合国维和行动的理念演变

联合国维持和平行动的指导理念随着国际局势的发展而不断变化,其中既有自身的发展与完善,也折射时代的演进和各种政治力量的对比。联合国维和行动产生初期遵循绝对中立理念,冷战后准军事介入阶段带有明显的隐性强权理念,反恐时代则对维和理念演变产生了新的影响。     

军体训练中常见运动损伤的原因及预防措施

在军事体育训练中,各种运动损伤是比较常见的,预防与处置不当会严重影响训练效果与训练质量,增加非战斗减员,因此要正确认识运动损伤,了解训练中可能发生损伤的原因,采取积极的预防措施,掌握运动损伤的发生规律,以便最大限度地避免和减少运动损伤,从而保证教学与训练的正常进行。