改进YOLOv5s算法在交通标志检测识别中的应用

针对复杂道路交通场景中交通标志检测识别精度低的问题,提出了一种改进YOLOv5s算法的目标检测识别方法.采用迭代自组织数据分析算法对TT100K数据集进行聚类分析选择更适合的先验框,新先验框能够更加全面地覆盖交通标志的尺寸,提高模型的检测精度;对特征图进行上采样操作,获得更大尺度的特征图后与主干网络特征图融合,得到特征信息更加丰富的新特征图用来小目标的检测识别,提高了小目标检测识别的精度;用真实框和先验框宽比和高比的差值替代真实框和先验框宽高比的差值对定位损失函数进行改进,解决了宽高比相同但实际尺寸不同时惩罚消失问题.实验结果表明改进算法与YOLOv5s算法相比,提高了9.55％的平均精度均值,对小目标的检测识别具有更好的效果.     

Reforming China’s defense industry

ABSTRACT

Even with sizable economic inputs, access to foreign technologies, and considerable political will, China, up until the late 1990s, experienced only limited success when it came to the local design, development, and manufacture of advanced conventional weapons. Not surprisingly, therefore, reforming the local defense industry in order to upgrade its technology base and manufacturing capabilities and to make armaments production more efficient and cost-effective has long preoccupied the Chinese leadership. The fact that most of these efforts had little positive impact on the country’s military technological and industrial capabilities only encouraged Beijing to experiment with additional reforms in the hopes of finally getting it right.     

The limits of covert action: SAS operations during ‘Confrontation’, 1964–66

This article evaluates the performance of the Special Air Service (SAS) during secret cross-border raids conducted as part of Britain’s undeclared war against Indonesia from 1963–1966. The analysis reviews the existing debate on the SAS’ performance during this campaign; it looks more closely at how military effectiveness might be defined; and it then examines, using the SAS’ own operations reports, the nature of their activities and their success or failure. This article concludes that critics of the SAS’ effectiveness during Confrontation are right; but for the wrong reasons. SAS operations did indeed have less effect than orthodox accounts would have it. But the reasons for this lay not in their misuse but in the exigencies of British strategy. This article demonstrates an enduring truth – no matter how ‘special’ a military force might be, tactical excellence cannot compensate reliably for problems in strategy.     

Swedish–Finnish naval cooperation in the Baltic Sea: motives,prospects and challenges

Recently, Finland and Sweden decided to substantially deepen their defence cooperation and this project involves creating a bilateral standing Naval Task Group (SFNTG). The present article aims at examining the deepening naval cooperation between Finland and Sweden from a regional integration perspective, focusing on its motives, current challenges and future prospects. Driven by perceptions of common challenges and desires for cost-effectiveness, and strengthened by recent successes on sea surveillance and a combined Amphibious Task Unit, the bilateral project has considerable potential to achieve success. To fulfil its objectives, substantial legal changes in both countries are required to allow the use of force on each other’s territorial waters. To cater for the requirement of not conflicting with EU, NORDEFCO or NATO cooperations, the bilateral Task Group must operate according to NATO standards and by using English as the language in command and control. The costs of adjusting the naval units to NATO’s technical requirements are far from negligible and this issue still remains to be solved. If Finland and Sweden manage to incorporate new policies, common structures and common organisational norms among their navies, an even deeper integration, as in Belgium and the Netherlands, are conceivable.