相控阵雷达LPI搜索方法研究

相控阵雷达可通过合理配置工作参数优化其性能。针对相控阵雷达在搜索目标时易受敌方电子侦察设备威胁的现实,研究了在保持搜索能力的同时,通过合理配置参数降低截获概率的问题。分析了影响相控阵雷达搜索状态LPI(Low Probability of Intercept)性能的主要因素,建立了截获概率模型与搜索能力模型,给出了3种参数调整策略。仿真试验验证了模型的有效性,并比较了3种策略的优劣。     

How does state security limit the right to protest? State response to popular participation in South Africa

In South Africa, the right to protest has come under threat from the state. Increasing cases of forceful policing and, at times, unlawful procedural prohibitions of protest attest to this. Interviews with members of different community-based organisations across South Africa show that protest is sometimes delegitimised under the guise of security as protestors are constructed as threats to the state. The larger implication of this treatment is that these protestors are treated as non-citizens who are excluded from participating in governance. This study aims to describe this situation through securitisation theory, arguing that South Africa has become a securitised state. It therefore looks at the implications of this securitised response for popular participation in South Africa.     

Explaining the security paradigm shift: strategic culture,epistemic communities,and Israel’s changing national security policy

The paper’s main argument is that Israel’s security policy, which traditionally focused on defending its territorial integrity against regular Arab armed forces, was, by the 2010s, transformed into one that focuses on facing a variety of state- and non-state-based threats. Neo-realist explanations could neither account for the contested nature of the security debate during this period, nor the inconsistent evolution of the policy. The present study aims to solve this conundrum by introducing an alternative approach known as 4th generation strategic culture research. The paper is comprised of four parts. First, the origins and evolution of strategic culture are reviewed, with emphasis placed on the commonly accepted weaknesses that, to date, have prevented it from being used as a testable theoretical concept, and subsequently as an explanatory factor for security policy changes. The second part presents the “modernist constructivism” approach that bridges the gap between traditional constructivism and hypothesis-driven research design. Next, the paper introduces the emerging fourth generation in strategic culture literature, followed by a conceptual framework designed to resolve the inherent weaknesses of the more traditional approaches. Finally, this conceptual framework is applied to analyse the transformation of Israel’s security policy between 1982 and 2014.