Sb变质对ZL107合金组织与性能的影响

ZL107合金经Sb变质后,能有效地使共晶Si由板条状变为粒状与孤块状,使α-Al枝晶分布均匀,并使棒状Al2Cu向小颗粒状转化.加入0.20%的Sb变质时,合金组织最为均匀,力学性能也最好.Sb进入合金后,吸附在Si的表面,阻碍了共晶Si的生长,使共晶Si片厚度的增加受到了抑制,AlSb质点的增多为α-Al形提供支撑,使口α-Al枝晶变得发达,分布均匀.经过T6处理后,合金的组织和力学性能得到进一步改善提高.     

Al-5Ti-1B对ZL107合金组织与性能的影响

研究了不同的Al-5Ti-1B细化剂加入量对ZL107合金组织与性能的影响.结果表明:Al-5Ti-1B对ZL107合金晶粒有良好的细化效果,当其加人量为0.20%(质量分数)时,合金中α(Al)二次晶臂平均尺寸最小,力学性能也最好;加入量大于0.20%时,性能开始下降.经过T6热处理后,合金的组织和力学性能得到进一步改善提高.合金细化是因为化合物TiAl3、TiB2等成为α(Al)形核的异质核心,并且TiB2能抑制α(Al)的快速长大.     

回火工艺对高速钢轧辊残余奥氏体和硬度的影响

采用正交表L9(34)设计高速钢轧辊淬火后的回火工艺;经XRD分析,采用K值法定量测量不同热处理工艺下高速钢轧辊中残余奥氏体和碳化物的含量;通过方差分析确定残余奥氏体最少和硬度达到HRC71以上的最优热处理工艺.     

基于相关性的人机系统可靠性模型

本文在剖析人机系统中操作者行为特征的基础上,考虑到操作者行为的自适应性、自学习能力及其行为形成主因子,着重结合操作者行为的相关性-感知作用于判断决策后影响到动作,建立了人机系统中操作者行为模式,并推导出计算操作者可靠度的公式,求出了相应参数.最后进行了实例量度,同时定量辨识了行为相关性对人可靠性的制约程度,以期从人机系统可靠性角度为人机系统的优化设计提供新的依据.     

基于多次致命性故障定量判定的复杂可修系统可信度建模的解 …

在定量识别多次致命性故障状态的基础上,通过对发生致命性故障事件和修复事件的描述,提出了复杂可修系统可信度计算的一般方法,同时详细地推导致命性故障和任务修复率为常数时复杂可修系统可信度的计算公式,并且展开讨论了发生多次致命性故障时复杂可修系统可信度的建模问题：最后以实例进行了可信度建模的工程化验证。     

Analyzing influence of bicycles on traffic flow using microscopic simulation approach

Mixed traffic consisting of cars and bicycles is a typical pattern of urban traffic in China.To study the impact of bicycles on traffic performance,a microscopic simulating model based on the principle of cautious driving and collision free was proposed.The interaction between cars and bicycles were described by lateral friction and overlapping driving.The dynamical features of speed and time-headway were investigated by numerical simulations.The results show that bicycles have a significant impact on travel speed and time-headway.The effect of bicycles can cause different results in the free flow phase and congestion phase respectively.The results also indicate the necessity to mitigate the interaction between motorized vehicles and non-motorized vehicles.     

Analysis of opposing left-turn conflicts based on traffic conflict technology

The relationship between the opposing left-turn conflict and the traffic participants was analyzed in this study. Based on the traffic conflict technology, the image data were collected in a real traffic situation. The relationship was investigated under two different conditions. The number of opposing left-turn conflicts was positively correlated with the number of left-turn vehicles while the ratio of left-turn vehicles to opposing vehicles was less than 1, and showed a positive correlation with the number of opposing-through vehicles when the ratio of left-turn vehicles to opposing vehicles was more than 1. In other words, the opposing left-turn risk was positively correlated with the number of the minor traffic participants, which had a negative effect on the whole traffic system operation.     

依据驾驶行为的动态分析辩识交通事故原因

通过建立的驾驶行为形成模型 ,推导出描述驾驶行为动态特征的可靠性表达式 ;然后 ,结合驾驶可靠性计算公式和驾驶行为形成因子的计算机仿真 ,提出了评价驾驶失误对驾驶员车辆系统动态性能影响的方法 .根据对驾驶员车辆系统中驾驶失误的分析得出 ,感知可靠度的变化增大了交通事故发生的可能性     

Analysis of metropolis parking problems and solutions based on GIS

The rapid development of the social economy strongly promotes the urbanization and motorization.Meanwhile,parking problems become serious due to the long-term imbalance between parking demands and facility constructions.Thus there is an increasing urgency in finding solutions for parking problems.Based on the methodology framework of geographic information system(GIS),the metropolis parking problems are discussed in this paper.The characteristics of parking demand and the reasons for parking problems are investigated in detail.Then,the basic parking principle and strategies for solving parking problems are suggested with the example of Beijing.The results are hoped to improve the parking environment in metropolis.     

彩色识别，证件管理迎来又一春

近年来，中国城市化建设进程的加速，人口流动日益频繁，证件识别成为了社会安全防范的重大课题，对证件识别产品的需求也有了很大的提高。随着技术的不断进步，产品的应用已进入到了具备网络化、集成化功能的全数字时代，尤其对于饭店、公安、医院、网吧这些行业来说，对身份证件信息的快速准确提取更是当务之急，同时这也是这些行业实现信息化的关键。因此，如何利用技术使登录的身份信息完整、高速、有效，利于管理和验证成为了系统中首要解决的问题。[编按]