密立根油滴实验的误差分析

针对测定电子的电荷量的密立根油滴实验,分析该实验误差产生的原因,根据误差传递和随机误差的统计分析理论给出总的随机误差.在数据处理过程中应用肖维勒准则推导出异常数值的判断和剔除的方法.     

单CCⅡ实现的Q增强二阶高通网络

本文提出了两种新型的Q增强二阶高通网络,仅采用一块第二代电流传输器(CCI)及四个无源元件,较用运算放大器实现的同类电路如Sallen—Key高通电路简单.     

腐蚀钼阴极尖端溶液的配制

报导了一种配制腐蚀阴极尖端溶液的方法，用这种方法配制的溶液来腐蚀钼阴极尖端，得到了尖端曲率半径为0．1——0．6μm，这样的阴极尖端其发射特性能够满足我们用这种金属（钼）树料来制作阴极尖端的要求。     

提高赴日研修生语言能力的几点思考

针对日本劳务市场发展趋势对研修生的语言需要,赴日研修生在日本语的教学方法、教材建设、师资力量等方面都需要根据实际情况予以重新调整和规划,提出相应的对策和措施。     

两类典型产业生态系统的建模及比较研究

基于两类典型的产业生态系统建立基本数学模型,提出清洁生产系数和耦合适应度系数概念,在运用数学模型对生态产业园区的几种类型进行解释说明的基础上,得出清洁生产具有广泛的适用性,生态产业园区和区域副产品循环网络具有相对的适用性,而技术创新是产业生态系统成功运行的关键因素等结论。     

运用模糊-证据理论对产业集群竞争力评估方法的研究

为科学地解决产业集群竞争力评估中的不确定性问题，综合运用模糊数学和证据推理方法，给出一种评估产业集群竞争力的方法。该方法主要运用模糊评价技术给出产业集群竞争力影响因素的评估等级，然后运用证据理论的层次递归算法对不同层次影响因素的评估等级进行合成，得出产业集群竞争力总体评估值；最后通过算例验证该方法的有效性。     

基于水平集方法的连续体结构拓扑优化方法研究

采用水平集方法描述结构的拓扑及其变化,使用紧支径向基函数对计算区域的水平集进行插值以得到参数化的水平集方法。针对给定体积约束下结构最小柔度的拓扑优化问题,推导了目标函数对插值系数的灵敏度及拓扑优化的迭代格式,数值计算表明,使用该方法进行结构拓扑优化得到的结果边界形状光滑连续且计算稳定性较好。     

Bullying, violence, and risk behavior in South African school students

OBJECTIVES: To examine the prevalence of bullying behavior in adolescents from Cape Town and Durban, South Africa, and the association of these behaviors with levels of violence and risk behavior. METHOD: Five thousand and seventy-four adolescent schoolchildren in grade 8 (mean age 14.2 years) and grade 11 (mean age 17.4 years) at 72 Government schools in Cape Town and Durban, South Africa completed self-report questionnaires on participation in bullying, violent, anti-social and risk behaviors. RESULTS: Over a third (36.3%) of students were involved in bullying behavior, 8.2% as bullies, 19.3% as victims and 8.7% as bully-victims (those that are both bullied and bully others). Male students were most at risk of both perpetration and victimization, with younger boys more vulnerable to victimization. Violent and anti-social behaviors were increased in bullies, victims and bully-victims compared to controls not involved in any bullying behavior (p<.01 in all cases). Risk taking behavior was elevated for bullies and bully-victims, but for victims was largely comparable to controls. Victims were less likely to smoke than controls (odds ratio .83, p<.05). Bully-victims showed largely comparable violent, anti-social and risk taking behavior profiles to bullies. Bully-victims showed comparable suicidal ideation and smoking profiles to victims. CONCLUSIONS: Results were in keeping with Western findings. Involvement in bullying is a common problem for young South Africans. Bullying behavior can act as an indicator of violent, anti-social and risk-taking behaviors.     

SAR自然场景实时回波模拟器的设计与实现

设计和实现了一种基于TS201 DSP处理器架构的合成孔径雷达技术(SAR)自然场景实时回波模拟器。阐述了实时回波模拟器使用的仿真模型,剖析了实时回波模拟器实现中的架构设计、并行设计和实时性监测等3个关键技术,介绍了实时模拟器的结构和模块组成,并通过点目标和自然场景的试验证实了模拟器的精确性和实时性。此实时回波模拟器能够根据更新的雷达飞行轨迹实时计算生成回波信号,可以为SAR实时成像处理机和成像处理算法研究提供快速的数据支持。