TERRORISM: FACTS FROM FIGURES 1

If international terrorism is on a rising trend, an important source of confirmation or refutation of this is time‐series data on terrorist activity. Using chiefly data collected by the RAND/MIPT consortium we show using basic statistical analysis that in the period 1968–2005 the yearly number of all international terrorist incidents shows no trend over time, but fluctuates year on year in a random manner. On the other hand some indicators do show a definite trend over time, principally the steady rise in the number of incidents that are death‐dealing in nature. A further conclusion is drawn, showing that the proportion of these incidents leading to deaths above a given level is virtually fixed.     

The view from above: how the Royal Air Force provided a strategic vision for operational intelligence during the Malayan Emergency

It has long been held that the Federation of Malaya’s counter-insurgency campaign during the First Malayan Emergency (1948–60) was determined by the use of intelligence. Special Branch — the Federation’s primary intelligence agency — dominates the prevailing paradigm of how the insurgent threat was tackled. Conversely, the role of the Royal Air Force (RAF) within this paradigm is very limited. Most observers simply dismiss the role of photoreconnaissance or airstrikes as being largely inconsequential to the counter-insurgency effort. This is perhaps understandable: the Emergency was after all a ‘policing action’ and the insurgents were largely hidden under Malaya’s jungle canopy and amongst the Chinese community. However, further scrutiny reveals that the RAF made a much more significant contribution to the intelligence element of the counter-insurgency campaign than previously realised. First, the RAF decided to locate their Advanced Headquarters with the Army’s General Headquarters. This led to the creation of the Land/Air Operations Room, through which intelligence, tasking and resources were coordinated. Moreover, the RAF put its intelligence teams into the field to provide a practical link between local units and theatre-level assets. Second, with the support of the Army, the RAF established at the beginning of the Emergency the Joint Air Photographic Intelligence Board (Far East). This coordinated all photographic intelligence requirements throughout the Emergency, which was then delivered via the Joint Air Photographic Centre (Far East). Hence, via Joint Operations Centre and JAPIB (FE), the RAF provided both the practical means for effective joint intelligence operations at theatre level throughout the Emergency.     

精密加工过程切削用量和表面粗糙度关系的模糊化处理方法

在金属切削原理中,用切削用量可以估计理论表面粗糙度。由于切削过程的复杂性,实际加工表面粗糙度和理论表面粗糙度有较大差距。本文采用模糊模式识别方法,对切削用量和表面粗糙度的关系进行了实验研究。本人介绍的理论方法、实现技术路线和实验结果,为以后开展ＦＭＳ或ＣＩＭＳ中智能化质量监控技术的进一步研究打下了基础。     

轮式装甲车辆的几何通过性建模与仿真

介绍了轮式装甲车辆通过障碍物的规则,分析了几何障碍物属性和通过判断条件,针对几何障碍物属性,提出了几何障碍物的通过算法,建立了几何通过性模型。采用VC＋＋编程对模型进行了仿真,通过仿真实验验证了算法和模型的可行性。     

履带车辆转向性能指标分析及实验研究

转向性能是评价履带车辆机动性的重要指标之一.文中针对转向角速度、转向半径和转向消耗功率3个指标,分别在不考虑履带滑转滑移的理想条件下和考虑履带滑转滑移的实际情况下,对履带车辆的转向性能进行了讨论和分析,对2种条件下履带车辆的转向性能的变化进行了比较.为了对履带车辆在转向过程中履带的滑转和滑移程度进行定量的分析,定义了履带的滑转和滑移系数.通过实车实验,对分析结果进行了验证.     

几何内蕴量对拉伸模具工作面力学性能的影响

曲率、度规不变量、凸凹性等几何内蕴量的不均匀分布直接影响模具的力学性能。本文研究了曲率与变形能、曲率与摩擦耗损功、度规不变量与热辐射、凸凹分布与辐射热通量等几何内蕴量与力学量之间的关系。结果表明:复杂曲面表面高斯曲率的不连续分布将导致表面的变形能、摩擦耗损功出现相应的不连续分布;型面上沿拉伸方向截面线的法曲率越小,摩擦耗损功越大;型面上的热通量会随着拐点数量的增加而增加。这些结果为模具表面优化设计提供了新的理论依据。     

van der Pol 振子在负反馈作用下的动力性态分析

本文从非线性振动理论和反馈控制论的角度研究了ｖａｎｄｅｒＰｏｌ振子在负反馈作用下的动力性态,用中心流形法和形式级数法分析了ｖａｎｄｅｒＰｏｌ振子的局部稳定性和Ｈｏｐｆ分叉行为,用Ｒｕｎｇｅ─Ｋｕｔｔａ法给出了仿真结果。     

2K-H 行星传动的极限传动比

在行星轮系机构综合中,研究行星轮数目与极限传动比的关系有着极其重要的意义。本文根据２Ｋ─Ｈ行星轮系机构的同心条件、安装条件和邻接条件,采用统一的符号,对满足上述条件的所有（六种）２Ｋ─Ｈ行星轮系机构,导出了行星轮个数与极限传动比的统一关系式,得到了所有２Ｋ─Ｈ行星轮系机构的极限传动比计算公式,为２Ｋ─Ｈ行星轮系机构的综合提供了理论根据。     

炸药装药在压剪加载下的起爆特点

进行了两类压剪加载实验：（１）利用石英的平面正碰撞产生压剪加载的实验,采用电磁质速法测试装药试件内部不同质点的运动情况,分析炸药装药中发生化学反应的可能性;（２）在压剪炮上采用平行倾斜碰撞产生压剪加载的实验,观测炸药装药爆炸的可能性。由实验可以看出：在亚爆轰状态的压缩加载应力条件下,剪切的联合作用对炸药的起爆起到敏化作用,适当比例的压剪加载造成更加敏感的炸药起爆响应。文中给出了起爆响应规律和响应机制的实验分析。     

基于纯方位信息的目标跟踪线性修正模型?

在基于几何关系的纯方位航迹不变量信息处理过程中,对非线性模型进行细致分析,提出了线性修正模型,在处理问题时更加清晰、可靠,减小了大量的计算和计算误差,使纯方位信息的非线性处理实用化。