燃烧方程在机动车尾气遥测系统的动态检测中的作用与分析

尾气遥测作为一种快速监测技术广泛应用于机动车排放监测,然而其动态检测的准确性评价手段有限。通过对比机动车尾气遥测系统的静态的校准方法,发现燃烧方程的辅助计算可以修正测量数据,克服仪器在动态测试中气体扩散的影响。利用燃烧方程分别归纳了以1,3丁二烯与丙烷为碳氢标志物的标准气体的比例关系,并配制和验证了2种标准气体用于机动车尾气遥测系统的动态准确度检测。研究结果表明符合燃烧方程的标准气体能够更好地表征仪器对低浓度组分动态测量结果的准确性。研究结果可为机动车尾气遥测仪检测用标准气体制备提供指导,优化动态准确度的计量检测条件。     

Efficient Dynamic Constraints for Animating Articulated Figures

This paper presents an efficient dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A non-trivial extension of Featherstone's O(n) recursive forward dynamics algorithm is derived which allows enforcing one or more constraints on the animated figures. We demonstrate how the constraint force evaluation algorithm we have developed makes it possible to simulate collisions between articulated figures, to compute the results of impulsive forces, to enforce joint limits, to model closed kinematic loops, and to robustly control motion at interactive rates. Particular care has been taken to make the algorithm not only fast, but also easy to implement and use. To better illustrate how the constraint force evaluation algorithm works, we provide pseudocode for its major components. Additionally, we analyze its computational complexity and finally we present examples demonstrating how our system has been used to generate interactive, physically correct complex motion with small user effort.     

高层建筑耦联风振响应分析

提出矩形塔式高层建筑三维风荷载模型和在三维风荷载作用下高层建筑耦联风振响应层间模型分析方法,并应用该方法对振型不同程度耦联的矩形塔式高层建筑加速度风振响应进行计算分析．分析结果给出了矩形塔式高层建筑的平动和扭转风振响应与振型耦联程度的关系,可为高层建筑的抗风设计提供参考．     

小浪底水利枢纽3号进水塔架的静动力分析

利用８～２１结点块体单元离散了３号进水塔,对５种工况进行了静动力分析,通过了１１个断面的内力值和闸室侧墙的应力状态计算,得出一些可作为设计依据的有益结论。     

新一代动三轴仪计算机数据采集与处理系统

在８０年代研制的动三轴仪基础上,采用现代计算机技术,实现了对动三轴试验全过程动应力、动应变和动孔压发展变化的实时采集、显示和数据文件在线存盘。不仅使数据处理过程全部自动化,且成功地解决了滞回圈等非规则曲线面积及莫尔圆公切线求解等一系列难题。     

浮盖式蓄水屋顶隔热功效研究

描述蓄水屋机的演变过程,推荐隔热效果最优化的浮盖式方案,提出蓄水屋顶动态襄减的新见解,分析影响衰减的主要因素。     

动态优化调度走向实用的策略与段落全局优化

本文在总结动态优化调度在实际系统中应用经验的基础上,提出了动态优化调度走向实用的策略及以段落一局优化算动态化调度的方法,该策略可以较地贯彻电力系统运行“安全,优质,经济”的原则,段落全局优化方法则可以一次性处理各种负荷紧段落,包括单调升降段落及以往方法只有通过反向导引才能够处理的陡升连续等类的段落,具有计算时间短,节省内存等特点,为动态优化调度在电力系统中的进一步实用化打下了坚实的基础。     

Reasoning about action and change

Reasoning about change is a central issue in research on human and robot planning. We study an approach to reasoning about action and change in a dynamic logic setting and provide a solution to problems which are related to the Frame problem. Unlike most work on the frame problem the logic described in this paper is monotonic. It (implicitly) allows for the occurrence of actions of multiple agents by introducing non-stationary notions of waiting and test. The need to state a large number of frame axioms is alleviated by introducing a concept of chronological preservation to dynamic logic. As a side effect, this concept permits the encoding of temporal properties in a natural way. We compare the relative merits of our approach and non-monotonic approaches as regards different aspects of the frame problem. Technically, we show that the resulting extended systems of propositional dynamic logic preserve (weak) completeness, finite model property and decidability.     

Hypercube sandwich approach to conferencing

This paper presents a novel cascaded conference network that provides distributed processing and signal transmission among members of disjoint sets of generic send/receive devices called conferees. It assumes an online request model in which idle groups of conferees may request the formation of a conference interconnection. Once a conference is established, all conferees remain connected until the entire conference is dissolved. The Hypercube Sandwich Network (HSN) consists of two components. A bidirectional permutation network is used for routing purposes to and from a hypercube of special processing elements for the purpose of conference formation. The HSN achieves strictly nonblocking performance for N conferees using O(Nlog N) processing elements, and this is shown to be tight to within a log ^1/4 N factor. Previous constructions required a quadratic number of processing elements for strictly nonblocking performance or could only provide wide-sense nonblocking conferencing. If the stronger requirement is made that the communication delay is logarithmic in the conference size, a simple algorithm is presented for wide-sense nonblocking conferencing in an HSN with O(N log N) processing elements.An earlier version of this paper was presented at the 1995 International Conference on Parallel Processing Techniques and Applications.     

僵尸网络检测技术研究

由于全球网络都在遭受日益广泛的僵尸网络所带来的威胁,因此,必须加大对其防治.僵尸网络检测的方法分为三个部分:“僵尸网络静态特征检测技术”、“僵尸网络动态特征检测技术”、“僵尸网络混合特征检测技术”,分别指出了僵尸网络静态特征检测技术的缺陷就是误报率高、僵尸网络动态特征检测技术缺乏先验性和处理数据量大等缺点,最后指出,把...