脉冲追赶式同步扫描下双基地雷达目标分辨力分析

脉冲追赶式同步扫描过程中,双基地雷达的目标分辨力不仅与雷达参数有关,而且还与脉冲追赶进程密切相关.分析了双基地雷达距离、角度和多普勒分辨力的影响因素,并对其在脉冲追赶情况下的变化规律进行分析,结果表明在每一脉冲追赶扫描周期内,双基地雷达的距离分辨力和多普勒分辨力不断提高,而角度分辨力则有所下降.     

用于自适应阵超角分辨的非均匀线阵设计问题

文中讨论了非均匀线阵自适应超角分辨问题,证明了在入射场条件一定的情况下,特征矢量角谱性能完全由阵列因子决定。通过分析与仿真,说明最小冗余阵(LMR) 是一种性能优良的超角分辨阵。并讨论了非均匀线阵存在的栅瓣问题,给出避免栅瓣的单位间距的上限公式。     

低分辨雷达基于波形特征的飞机架次判别方法

通过分析低分辨雷达飞机目标回波波形,提取出低分辨雷达飞机目标架次可资分类的特征参数作为飞机目标架次判别的特征向量。最后,采用模糊极大极小神经网络作为分类器,在低分辨雷达目标识别样机系统对机群目标进行分类识别试验中,验证了所提取特征的有效性。     

ENO格式应用分析

对一类高阶、高分辨率的ENO格式进行了较为详细的讨论。通过一些典型算例的应用和同常用TVD类型格式的比较 ,说明了在计算中采用高阶格式分辨复杂流动结构的优越性。在对格式应用分析的基础上 ,指出了格式应用中需注意的问题。通过定量分析说明 ,高阶ENO格式在计算中 ,不但能够减少网格规模 ,而且能够明显提高计算物理量 ,特别是其导数的计算精度     

The resource-conflict debate revisited: Untangling the case of farmer–herdsman clashes in the North Central region of Nigeria

The resource debate is easily discerned as part of the ongoing history of farmer–herdsman conflict in the North Central region of Nigeria. Scarcity theorists are adept at linking scarcity with the onset of livelihood conflict while on the other hand resource abundance pundits insist it is profusion and not scarcity that impels conflict. This article traverses these wrangles and proceeds to downplay the resource polemic altogether. It is proposed that the resource debate, despite its profoundness, presents a narrow reading of farmer–herdsman clashes in Nigeria’s North Central region. It is suggested that a number of other factors, including elite land grabbing, ethno-religious identity construction, weak state capabilities, the citizenship question, corrupt traditional institutions, the lack of an effective land tenure system and a widespread culture of impunity, make for better readings of the conflict. Owing to the negative impacts of the conflict on state and society, it is recommended that the state in Nigeria should commit itself to addressing the citizenship question, strengthening the capabilities of security institutions, extirpating the culture of impunity and revaluing its policy on land redistribution.     

Interstate border disputes in Africa: Their resolution and implications for human rights and peace

Many researchers have focused on the role colonialism has played in causing interstate border disputes in Africa. Besides the colonial issue, this paper seeks to investigate what other factors fuel interstate border disputes in Africa and determine how effectively the disputes can be resolved. In recent decades, Africa has been tormented by and is still experiencing numerous interstate border disputes which have serious implications for the disputing states. Some of the disputes are resolved, but violations of human rights and instability still occur in these regions. By analysing the content of some relevant documents and with the use of interviews, this paper reveals that most disputing African states rely heavily on foreign intervention (especially by their erstwhile colonial masters) in the resolution of their disputes. It is argued that African leaders need to be more committed and exhibit better leadership in resolving their border disputes, and that they should always seek the expertise of African forums such as the African Union (AU) before calling for foreign intervention. It is suggested that African leaders and the AU understand the problems of Africans better than anyone else, and they are also the ones mostly greatly affected by these disputes. Thus, there needs to be more of a focus on addressing the root causes of disputes in order to avoid them resurfacing, rather than seeking to merely halt them.     

一种基于部分搜索的GNSS模糊度解算方法

为解决LAMBDA算法搜索策略效率不高的问题,提出了一种基于部分搜索的模糊度解算新方法。该方法的解算成功率接近LAMBDA算法,且只需对最后3维模糊度元素采取搜索策略。同时,通过合理设定搜索椭球的大小和搜索策略;大大提高了搜索效率。通过实验对该新算法与Bootraping算法、LAMBDA算法进行了比较分析,进一步验证了该新算法的有效性。     

Resource rents,institutions, and violent civil conflicts

Natural resources have been blamed for inducing slow growth and sparking civil conflicts and violence. This paper first develops a model to account for the hazard of armed civil conflicts as a manifestation of the natural resource curse, which is mediated by the quality of both economic and political institutions. We then use recently published data on institutional quality and natural resource rents to measure the potential impact of the resource curse on violent civil conflicts using a panel of data for over 100 countries in the period 1970–2010. Our model explicitly accounts for the role of good economic and political institutions in deterring the recourse to violence as well as the extent to which they might weaken the resource rents effect.     

Resource Dependence and Armed Violence: Impact on Sustainability in Developing Countries

The dependence on oil, gas, and mineral exports arguably has a negative impact on economic growth in resource-rich, developing countries. This article looks at the impact of resource dependence on adjusted net savings (ANS) as an indicator of weak sustainability. Our results, based on a panel of 104 developing countries during the recent commodity price boom, confirm a negative relationship between resource extraction and sustainable development as measured by ANS. We further look at the specific role of armed conflict and armed violence as captured by the homicide rate. Armed conflict, which is positively associated with resource dependence, negatively affects ANS per capita according to both our OLS and instrumental variables (IV) estimates. Similarly, armed violence has a detrimental effect on sustainable development. Our IV estimate suggests that a one-point increase in the homicide rate decreases ANS per capita by $60. Since education expenditures are a critical ANS component, we further examine the impact of resource dependence and violence on human capital. Consistent with previous findings, resource-dependent countries underinvest in education but armed conflict and violence do not affect the instantaneous share of education expenditures, hinting at a detrimental effect working through physical and social capital rather than education.