基于VISA和SCPI的自动校准程序开发

描述了在VC++环境中开发的基于VISA接口标准的射频半实物仿真系统校准自动测试程序.利用VISA函数与接口无关、与操作系统无关、与编程环境无关的特点,通过GPIB总线和SCPI标准命令对矢量网络分析仪进行程序控制,达到空间辐射信号精确测量的目的,实现了目标阵列的宽带特性校准.     

基于无线局域网MAC层DOS攻击的入侵检测

为了检测无线局域网MAC层的6种DOS攻击方式,提出一种基于Hybrid特征选择和支持向量机的入侵检测算法.该算法先用混合器模式的Hybrid特征选择算法提取8个识别攻击的流量统计特征,然后利用支持向量机对待检测对象进行识别分类.通过建立仿真环境对检测模型的检测效果进行统计验证,表明检测模型在具有较高检测准确率和较低的虚警率,能够有效地检测MAC层DOS攻击,具有实用价值.     

频率选择表面研究与设计

对频率选择表面进行了研究,通过研究不同结构的频率选择表面,在现有介质材料的基础上设计了一种具有带通特性的频率选择表面,并用Ansoft HFSS进行了仿真设计.在20％带宽内实现了垂直照射传输损耗小于-2 dB,并研究了电磁波在不同入射角度下的传输特性.     

三星时差定位系统欺骗干扰效能评估

通过简单复制转发被保护目标信号可对三星时差定位系统进行欺骗干扰.目前对于三星时差定位系统欺骗干扰效能评估的研究鲜有公开资料发表.分析了针对三星时差定位系统的转发式欺骗干扰原理,提出了将假目标数量和虚假目标干扰分布熵2个评估指标结合的干扰评估方法.通过仿真分析对转发式欺骗干扰效能进行了评估,实验结果验证了所提方法的有效性.     

高中生饮酒行为及心理影响因素研究——以石河子市某高中为例

目的：研究高中生饮酒现状及相关心理影响因素。方法：采用问卷调查的方法,对在石河子市某高中就读的500名学生进行问卷调查研究工具：酒精使用障碍筛查量表（AUDIT）。UCLA孤独量表（第三版）。焦虑自评量表（SAS）结果：①高中生中不饮酒者323人,占受调查人数”．9％,饮酒学生114人;占受调查人数26．1％。饮酒者中男生74人,占39．6％,女性40人。占16％。②高中生饮酒情况因年级、性别、母亲饮酒、朋友饮酒而有所差异（P〈0．05）。具体表现为：男性、高年缴、母亲饮酒者、朋友饮酒者,其自身饮酒情况较重。③高中生饮酒与孤独感负相关,与焦虑正相关（上述结果p〈0．05）。     

The impact of military spending cutbacks on economic activity in an incentive‐wage two‐sector aggregative economy∗

We examine the theoretical outcomes of disarmament on economic activity in a two‐sector model of endogenous equilibrium unemployment rate. Three main shocks are analyzed: Exogenous cutbacks in military spending on the capital good and employment, and a reduction in public sector debt. The first shock is contractionary for equilibrium employment if the capital‐goods producing sector is relatively labour‐intensive but expansionary under the alternative factor intensity assumption. The second shock is contractionary for employment under either relative factor intensity assumption. If Ricardian equivalence fails, a reduction in public sector debt is likely to expand long‐term employment (JEL E24).     

Investigating optimal replacement of aging air force systems

An availability‐oriented approach has been developed to decide when to replace an aging system. For an existing system, it is optimal to operate another year if and only if the incremental cost per available year is less than the lifetime average cost per available year of a new aircraft. We illustrate our approach using United States Air Force KC‐135 tanker data. In demonstrating our approach, we find it will be optimal to replace the KC‐135 by the end of the decade.     

The ‘African COP’

The 17th Conference of the Parties (COP17) had been anticipated as the ‘African COP’, not only due to the African venue but also due to the opportunity it would afford African countries – with South Africa at the helm – to steer the debate on a global climate change regime. With the conference now over, lobby groups, international organisations, negotiators, observers and commentators alike have been taking stock of its outcome. Despite the litany of developmental and security implications of climate change, COP17 got underway with little hope that much might actually be achieved. In light of the discouraging condition of the global economy, with leading developed economies suffering financially, states were hardly in a mood to be making concessions that would impact their fiscal health. Nonetheless, an agreement was reached. Questions remain, however, about the significance of the outcome of the African COP for the world at large, but ultimately also for Africa.     

Boko Haram and the challenges of Nigeria's war on terror

Boko Haram terrorism has been recognized by Nigerian President Jonathan as the most threatening and complex security issue in Nigeria since independence. In response, the Federal Government of Nigeria has committed itself to different counterterrorism measures, which are largely dominated by “hard politics” and military mobilization. Spending heavily on defense to upgrade military hardware and train personnel in a counterterrorism role, Nigeria has also boosted its strategic importance in the “Global War on Terror”. However, this attempt has become unpopular as it has failed to contain Boko Haram within a short time frame and has made insufficient headway against unabated terror, with human rights costs among the host communities and amidst a surge of stakeholders' discordance. As a matter of concern, this article seeks to assess Boko Haram as an opponent in Nigeria's war on terror (WOT) and to ascertain the challenges the country faces, the alternative measures open to it, and possible ways forward.     

微污染地表水的胞外聚合物复合絮凝剂强化混凝处理

采用胞外聚合物作为生物絮凝剂,开展胞外聚合物复合絮凝剂强化混凝处理微污染原水的研究.研究结果表明,蛋白质是胞外聚合物最主要的成分,多糖次之,腐殖酸和脱氧核糖核酸的含量最低;胞外聚合物含有大量带负电荷的官能团,单独投加胞外聚合物不能有效絮凝和吸附去除原水中的污染物.聚合氯化铝混凝处理微污染水的效果优于氯化铝和聚合硫酸铁,药品较优投加质量浓度为70~80 mg/L.胞外聚合物和聚合氯化铝复合使用能提高对细小颗粒物的去除效果,增强去除有机污染物和氯化消毒副产物前驱体的能力,降低聚合氯化铝的质量浓度.胞外聚合物复合絮凝剂的较优配方:胞外聚合物质量浓度为5 mg/L,聚合氯化铝质量浓度为60 mg/L.