某型火箭增程破甲弹发动机弹道炸分析与处理

根据某型火箭增程破甲弹,在研制阶段做高、底温强度试验时分别出现发动机弹道炸的质量问题,结合实践在理论方面进行了分析,提出了对发动机燃烧室内个别件改进设计的方法。     

Military deployment and international terrorism: do location and mission type matter?

Extant literature documents a relationship between military deployment and the risk of an international terrorist attack against citizens of the deploying country. It appears that deployment significantly increases the possibility of terrorist actions in the home country. In particular, if country A decides to send troops to nation B, then citizens of the former country are more likely to fall victim of an attack carried out by a terrorist organisation originating from the latter country. Contributing to this line of literature, we further refine this relationship by distinguishing between regions where the troops are sent as well as by introducing differences between types of deployment. Our results indicate that missions to Asia and the Middle East are more dangerous than missions to other regions as reflected by the terrorist threat in the home country. Robustness tests do however show that the significance of the location variable Asia is predominantly attributed to the mission to Afghanistan. As for types of deployment, only ad hoc missions seem to increase the risk of an attack, whereas no significant results are found for other missions such as operations under UN and NATO flag. Leaving out the missions to Iraq and Afghanistan however also increases the danger resulting from missions by fixed coalitions. Our results find however no evidence that ‘wearing a blue helmet’ increases the probability of a terrorist attack at home.     

The Blind Basinet: A New Interpretation of Royal Armouries IV.2

For many years a curiosity in the collection of the Royal Armouries, IV.2, or the ‘Blind Basinet’, is a fascinating example of an early 16th century great basinet not so much for what is present but for what is not. The lack of any means of seeing out of the helmet has led to a number of traditions regarding its provenance and purpose. A detailed examination of the helmet’s interior, as well as comparison with some other contemporary pieces, shows that it is an unfinished piece of armour. It was left at the stage where the sights and breaths would have been pierced, but they were left unfinished until some later modifications created a display piece, one which can still be seen at the Royal Armouries in Leeds.     

Greek Armour at the Tower

In the following short notice, the authors tell the story of the appearance of Classical armour in the Tower Armouries in the early and mid-nineteenth century. In the first part, Malcolm Mercer describes the interest surrounding armour from Cumae and the circumstances of its purchase by the Ordnance Office; while in the second Thom Richardson presents a specialist analysis of this group.     

Tailored to the Times: The Story of Casimir Zeglen’s Silk Bullet-Proof Vest

Abstract

The invention of silk bullet-proof fabric, a response to growing violence and anarchy, and intended to protect politicians and public figures, as well as police officers and soldiers, is discussed in the wider context of the world’s political situation at the turn of the 19th century. The complex question of the ownership of this innovation is addressed and the reasons for its commercial failure are discussed. The ballistic properties of silk bullet-proof fabric are evaluated and the impact of this invention on the future development of soft armours is considered.     

Boko Haram’s increasingly sophisticated military threat

ABSTRACT

This paper evaluates Boko Haram’s military capabilities and details the process of how its standing army, driven by these capabilities, came to pose a phased threat between 2013 and 2015 in particular. This was a period when military fighting dominated the insurgency in north-east Nigeria. Whereas there is an abundance of literature on Boko Haram’s histories and the impact of its insurgency on north-east Nigeria, analysis of Boko Haram’s military campaigning is still deficient. Attempting to fill this gap, this paper uses field findings and battlefield case studies from north-east Nigeria to highlight how Boko Haram’s overt front – its standing army – came to supplant its guerrilla operations as the main security threat to the frontier area.

This pivot towards military fighting, for a group initially composed of a few ragtag combatants, on the surface might seem surprising. Yet, whereas Boko Haram may lack the popular support required for ‘people’s war’, classic insurgency theories nevertheless hold some explanatory power for this deliberate shift: away from guerrilla warfare as the expedient of the weaker side, and towards the use of a large standing army of locals to swarm, and sometimes successfully overrun, state forces.     

Body armour – New materials,new systems

This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve – a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in on-going developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.     

多刚体系统计算机代数动力学建模研究

本文研究了复杂多刚体系统的Ｌａｇｒａｎｇｉａｎ建模方法，以Ｍａｔｈｅｍａｔｉｃａ数学软件为基础，完成了多刚体动力学系统的计算机建模、推导与仿真。     

The Production and Deposition of the Guisborough Helmet

In September 1878 the British Museum received a donation of a folded metal plate which had been embossed and gilded. Restoration of the object revealed that the folded plate was in fact the outer casing of a Roman copper alloy cavalry sports type helmet which dates to the late second or third century AD. The story of what became known as the Guisborough helmet began 14 years earlier in what was then the North Riding of Yorkshire when workers employed by the Cleveland Railway Company discovered a ‘very curious plate of metal’ during road construction. It appears that the helmet was deliberately prepared for deposition and buried at a depth of c30 cm close to a stream. Examination by the authors suggests that this was a high value item that had been repaired many times. Experimental evidence suggests that the decoration alone required approximately 16 h to fashion.     

Armour in Henry V’s Great Wardrobe

Abstract

The unpublished accounts of two of King Henry V’s armourers, Martin Pull and John Hill, shed new light on the armour worn by the king and his circle during his campaigns to France which culminated in the great victory at the battle of Agincourt in 1415.