基于尺度空间理论的角点检测

传统的Harris角点检测是一种经典的角点检测算法,但不具有尺度不变性。研究了一种基于尺度空间理论的Harris角点检测方法。建立Harris的尺度空间函数表示。利用多尺度分析的思想,使在小尺度上的角点精确定位和大尺度上的角点去伪存真。从而克服了传统的Harris角点检测可能存在的角点信息丢失、角点位置偏移和易受噪声影响等问题。试验结果表明,该算法明显地提高了图像角点检测性能。     

一种改进的应用于高速目标角点检测的AFJHA算法

针对经典Harris角点检测算法对于全局像素点求取角点响应函数所带来的计算复杂度高,从而不适合实时检测的弊端,提出了一种新的快速角点检测算法。鉴于角点数量只占整个图像像素点很小一部分,首先利用四方向亮度导数来进行候选角点预判断,阈值选取为图像像素点像素值的标准差的倍数。经过预判断后,再考虑8-邻域相似点个数,根据相似点个数对应的情况对候选角点进行再判断,将剩下的候选角点进行Harris算法检测。仿真结果表明,此改进算法能够有效地提高角点检测效果并减少检测时间。     

基于多尺度小波变换的二维图像角点检测技术

提出一种基于多尺度小波变换的二维图像角点检测算法。首先利用二维零交叉边缘检测算子对图像进行边缘提取得到二值边缘图，通过基于边素（边过程）的围线跟踪算法得到图像的边缘围线。对边缘围线的方向曲线进行多尺度小波变换，利用变换结果的局部最大值信息检测和定位出图像角点。仿真结果表明该算法可有效地实现二维图像的角点检测与定位，具有较高的精度     

基于三维Hough变换的机载激光雷达平面地标提取

针对机载激光雷达点云数据中的平面地标检测问题,分析了以三维Hough变换为基础的传统的平面检测算法,指出其存在空间分割不一致问题,在检测法线垂向地标时出现"极点"现象。研究了三维Hough变换的空间完备分割条件,利用参数空间的对偶特性,提出了一种基于对偶空间分割的三维Hough变换算法,避免了空间不一致问题。仿真和实验证明,改进三维Hough变换算法在不增加计算量的同时,能够有效检测激光雷达点云中的平面地标。     

应用全站仪综合测量火炮偏离角及俯仰半径

提出一种应用全站仪进行火炮偏离角和俯仰半径的综合测量方法。应用最小二乘原理拟合出火炮俯仰半径,然后解算出火炮偏离角,并用Monte Carlo方法分析了测量结果的精度。结果表明:全站仪高低角和火炮仰角的测量精度均对火炮偏离角和俯仰半径的测量结果无明显影响;全站仪测距精度对火炮俯仰半径测量结果的影响较大;全站仪水平角测量精度对火炮偏离角测量结果的影响明显。该方法在现场操作时需要重点关注全站仪水平观测角和测距的检测精度。     

球形译码算法中不均匀半径分配方案及性能分析

在球形译码算法中,初始半径的选择与分配是影响算法性能与复杂度的重要因素.针对球形译码算法在低信噪比时复杂度高的问题,提出了一种新的基于V-BLAST信号模型的初始半径选择与(准)线性半径分配方案,并分析了应用该方案的两种典型球形译码算法流程的性能与复杂度,其分析方法适用于任意不均匀半径分配方案.分析与仿真表明,与传统的球形译码算法相比,在信噪比较低时,采用该方案的球形译码算法的复杂度显著降低;在较宽信噪比范围内,其误码率性能接近最大似然检测性能.     

脉冲压缩雷达两种测角方法的比较

目标的角闪烁在近距离对跟踪雷达产生严重的影响,不能有效抑制角闪烁将有可能导致角跟踪失败。研究了2种抑制角闪烁的方法,即利用RCS和角闪烁之间的相关性抑制角闪烁方法及利用过门限相参信号各点计算角误差并使用这些角误差的均值解算角误差的方法。通过实采近距离大型渔船数据对比了2种方法,实验结果表明使用过门限相参信号各点计算角误差并使用这些角误差的均值解算角误差可更好地抑制角闪烁。     

基于不变矩和角点特征的目标识别*

在基于图像的识别系统中,图像发生几何变化或目标被部分遮挡会给识别带来困难,这时必须根据具体情况提取合适的目标特征。基于矩原理,运用Harris多尺度角点检测及SIFT(Scale Invariant Feature Transform)描述算法,研究了基于不变矩和角点特征的目标识别算法。两种特征都具有平移、旋转、尺度不变性。仿真分析表明,在理想情况下,利用不变矩可以获得较高的识别率;而当目标被部分遮挡时,角点是一种有效的识别方法     

一种有效的红外弱小目标DBT算法研究

作为红外自寻的制导、搜索跟踪和预警等领域的一项关键技术,红外弱小目标检测与跟踪成了红外图像处理领域中的一项重要研究课题。本文采用了"先检测后跟踪(DBT)"的思想对红外小目标进行检测与跟踪,首先采用基于各向异性偏微分方程的背景抑制技术对单帧图像进行抑制,再用最大绝对对比度阈值对红外图像进行分割,最后采用形心跟踪法对小目标点坐标定位。试验证明本文算法应用于目标检测的可行性和有效性。     

基于轨迹预测的二阶DPA扩散抑制方法

二阶动态规划算法(DPA)是一种有效的点目标检测算法,能够在低信噪比条件下检测目标,但也存在着评价函数扩散等缺点。针对二阶DPA的这一不足,提出了抑制二阶DPA评价函数扩散的方法。与其他抑制方法相比,提出的方法既有效地降低了噪声对检测过程的影响、抑制了评价函数扩散的现象、提高了对目标的检测能力,又更适合于硬件实现。     

Terrorism,insurgency, kidnapping,and security in Africa's energy sector

Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).     

Helping hands: civil–military cooperation and Italy's military operation abroad

In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.     

Tacit support for terrorism: The rapprochement between the USSR and Palestinian guerrilla organizations following the 1967 war

This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.     

A1 Qaeda and the radical Islamic challenge to western strategy

The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.     

Helping hands: external support for the KNU insurgency in Burma

This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.     

基于GTST-DMLD-ESD的装备RMS建模仿真

装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.     

Cyber sheiks and grassroots jihadis: the war in Syria and the devolution of the Bosnian Salafi communities

ABSTRACT

What was the scope of the Bosnian jihadi participation in the war in Syria? Did the Bosnian volunteers tend to join one particular faction? Why did the Bosnian youngsters decide to join the holy war in the Levant? Was this an organized and hierarchical process or was this a grassroots movement? Last, were all the Salafis in Bosnia supportive of this dynamic or did this process cause internal frictions? These are some of the questions that this research will try to answer.     

The UK,interrogation and Iraq, 2003–2008

The UK’s interrogation operations during the conflict in Iraq (2003–2008) are often portrayed by the media as involving significant amounts of mistreatment. This article demonstrates that these practices are not necessarily representative of the UK’s interrogation operations across this conflict. In doing so it contributes to the limited literature on the practice of interrogation and on the UK’s combat operations in Iraq. The UK’s interrogation capability, and therefore its intelligence-gathering capability, is shown to have rested primarily with the military’s Joint Forward Interrogation Team (JFIT). The JFIT suffered from limitations to the number, training and experience of its interrogators and interpreters. It is argued that maintaining a permanent, higher level of preparedness for interrogation by the British armed forces is desirable.     

Remembering and forgetting Mirambo: Histories of war in modern Africa

ABSTRACT

While the study of organised violence is considered essential to understanding the history of the West, and accordingly imbued with various layers of meaning and remembrance, war is widely regarded as inimical to the modern nation in Africa and stable development more broadly. Using examples drawn from primarily from East Africa, this paper considers the ways in which warfare in the deeper (‘precolonial’) past has been framed and envisioned in recent decades, in particular by governments whose own roots lie in revolutionary armed struggle and who began life as guerrilla movements. While in some cases particular elements of the deeper past were indeed mobilised in pursuit of contemporary political goals, in many other scenarios histories of precolonial violence were beheld as problematic and unworthy of remembrance. This paper highlights the paradox and ambiguity which has attended the memory of key aspects of Africa’s deeper past.