谈CAI在化学教学中的作用

本文从CAI在化学教学中可以提高教学水平和质量,培养学生自学和创新思维的能力,提高教师的业务素质三方面进行了探讨,分析了CAI在化学教学中的作用。     

基于估计协方差MME检测的频谱感知算法

针对小采样数据长度下,采样协方差矩阵对统计协方差矩阵估计不准,影响传统最大最小特征值(MME)检测算法检测性能的问题,提出一种基于逼近收缩(OAS)矩阵估计的改进MME检测算法。首先利用OAS估计量对采样数据做协方差矩阵估计,再对估计协方差矩阵特征值分解,将最大最小特征值之比作为检测统计量,克服了传统MME算法检测门限随采样点大幅波动的缺陷,提高了检测门限的鲁棒性。仿真结果表明,所提算法的检测门限具有鲁棒性,检测性能提高了1 d B~2 d B。     

Socioeconomic impact of conflict: state of emergency ruling in Turkey

Uprising tensions during 2010 in eastern and southeastern regions of Turkey provoked arguments about the necessity for a State of Emergency (SOE; ‘Ola?anüstü Hal’ in Turkish) declaration in those regions, with a belief of enduring political sustainability. The discussion is inflamed by a speech of the Nationalist Movement Party’s leader about the suggestion to announce a SOE ruling after the death of 24 Turkish soldiers in Hakkari (a city in the southeast of Turkey) in an attack of the PKK (Kurdistan Workers’ Party) on the 19 October 2011. Although a new announcement of SOE did not take place, the discussion itself induced the idea behind this paper which is to provide a quantitative analysis of the SOE in Turkey. In fact, the SOE ruling is not a new concept for Turkey and it has been implemented in 13 cities in the eastern and southeastern regions from 1987 to 2002. Although there have been many discussions about the costs of these 15 years of the SOE ruling in terms of military expenditure and, thus, on the national budget, there is a lack of quantitative analytical examination of the economic and social costs of it. Difference-in-differences analysis reveals negative spillover impacts of the SOE, especially on the forced migration, unemployment, and educational investments. The results also show that SOE ruling is an important factor for the underdevelopment of the eastern and southeastern regions in Turkey and, thus, a new SOE will bring enormous inequalities, both economically and socially, and an intensification of the ethnic tensions in Turkey.     

侧壁激波诱导下凹腔燃烧室冷态流场实验观测

在单凹腔燃烧室中引入侧壁激波,为研究燃烧室内部流动特性,采用纳米粒子平面激光散射技术和粒子图像测速技术对全尺寸玻璃燃烧室模型进行流场观测,获得了冷态流场展向和法向的瞬态灰度图及平均速度场。实验结果表明:在远壁面区域,凹腔内部速度与密度都较低;引入侧壁激波后,近壁面区域凹腔与主流的质量与动量交换增强,速度与密度升高;受到侧壁激波影响,燃烧室底壁边界层不再均匀,凹腔中后部产生大规模低速区,具有明显三维特性。     

蜂窝网络中基于干扰控制的D2D通信联合资源分配方案

在蜂窝网络中部署D2D(Device-to-Device)通信能够有效提升频谱利用率,降低基站负载,但D2D用户与蜂窝用户共享无线信道时会产生信号干扰。提出了一种联合资源分配算法,通过综合考虑信道分配对网络中已有的蜂窝用户和D2D用户的信号干扰,并在小区范围内寻找具有最小干扰值的信道资源分配给用户,以实现有效的干扰控制。仿真结果显示:联合资源分配能够提升D2D链路、蜂窝链路的信噪比及系统总吞吐量,使得蜂窝网络的整体性能优于独立资源分配。     

China’s Search for a ‘Strategic Air Force’

Once dismissed by many outside observers, the Chinese People’s Liberation Army Air Force (PLAAF) has undergone an impressive transformation over the past two decades, emerging as one of the world’s premier air forces. As it continues to modernize, it is focused on becoming a ‘strategic air force.’ PLAAF strategists suggest this means it should play a decisive role in protecting Chinese national interests, field modern capabilities commensurate with China’s standing as a major power, and enjoy the institutional status befitting its role as a ‘strategic service,’ an important consideration given the historical dominance of the ground force in China’s military.     

基于CMAC的模糊神经网络方法

结合模糊神经网络和小脑模型连接控制CMAC理论,提出训练时间短、精度高的CMAC模糊神经网络方法,给出了网络结构、算法,并通过一个维修经费预测实例讲述了这种算法.     

AUV纵倾角动态面滑模自适应控制

对于自主水下机器人(AUV)纵倾角跟踪问题,提出一种基于动态面滑模思想的自适应控制方法。首先对自治水下机器人纵倾角运动模型进行简化,其次针对不确定外干扰的情况,设计了自适应规律,对外干扰进行估计,在此基础之上设计了动态面滑模自适应控制器,并通过李雅普诺夫稳定性理论证明了系统的稳定性,最后通过给定参数的仿真实验结果可知,所设计的控制器在系统受到不确定外干扰时,表现出良好的鲁棒性。     

信息综合管理平台中基于内容的图像检索

文中深入分析了信息综合管理平台在宽带信息网络中的地位,提出了新型的信息综合管理平台的体系结构,重点研究了信息综合管理平台中对图像信息进行基于内容的管理和查询的原型系统,提出并研究了该系统中的关键技术和实现途径。利用这个基于内容的图像信息管理平台,可以对图像信息进行统一的管理和检索,对下一步信息综合管理平台原型系统的全面实现具有很高的实用价值。     

基于集对分析的航材保障效能评估

航材保障是航空兵部队技术保障的物资基础,其效能直接影响空军武器装备的作战效能.应用集对分析方法在确定随机系统中的某一特性上具有同异反定量刻画的特点,通过建立各系统航材保障效能评估指标的集对,据此对航材保障效能进行评估,最后得出一组合理的评估结果.