A visual tool for computer supported learning: The robot motion planning example

We introduce an effective computer aided learning visual tool (CALVT) to teach graph-based applications. We present the robot motion planning problem as an example of such applications. The proposed tool can be used to simulate and/or further to implement practical systems in different areas of computer science such as graphics, computational geometry, robotics and networking. In the robot motion planning example, CALVT enables users to setup the working environment by creating obstacles and a robot of different shapes, specifying starting and goal positions, and setting other path or environment parameters from a user-friendly interface. The path planning system involves several phases. Each of these modules is complex and therefore we provide the possibility of visualizing graphically the output of each phase. Based on our experience, this tool has been an effective one in classroom teaching. It not only cuts down, significantly, on the instructor’s time and effort but also motivates senior/graduate students to pursue work in this specific area of research.     

Mechanics of Autonomous Gas-Dynamic Torpedo Motion in Loose Medium

A new technology is considered for realizing the motion of solid body in the loose material due to alternating pulse ejections of compressed gas in the regime of traveling wave near the outer surface of the body. The dimensionless parameters are determined for scale modeling. The relation between the action factors and the value of motion is established empirically.     

中频变频器UFV故障探析

本文对中频变频器的UFV故障进行了系统试验和原因分析，并对UFV故障的关键因素进行了详细探析。     

氧浓度对近临界水中纤维素分解的影响

研究了不同初始氧浓度对纤维素在近临界水中分解的影响，实验结果表明，氧浓度显著地影响产物总碳收支平衡，液相不同组分的收率、气体的产量以及气相产物的组成，微量氧对产物总碳收支平衡影响不大，而对液相不同组分的收率有一定的影响。从实验结果可以看出，离子型反应机理在纤维素水解的第一步中起主导作用。而单糖的进一步分解是一个以自由基反应机理为主的过程。     

优化印制电路板地线设计

印制电路板地线是印制电路板设计的一个基本问题，本文详细分析了印制电路板地线对电路的干扰，介绍了减小地线对电路干扰的方法，阐述了印制电路板地线的设计规则，将其应用到实际的印制电路板设计中，可大大提高印制电路板的抗干扰能力，实现电磁兼容。     

大型结构物自动称重过程的计算机控制技术

大型结构物的称重通过多个千斤顶同步顶升实现。大型结构物往往存在柔度大、重量分布不均、支点跨距大的特点。在称重过程中需要进行计算机同步控制,实现结构物的平稳顶升和下降。大型结构物自动称重以工控机为核心,基于现场总线技术,对压力传感器、位移传感器、状态设置开关、油泵换向阀和油管超高压电磁阀等设备进行网络监控,对多个支点同步协调控制和结构物的精确称重,该系统已在多个油气田工程的建造中得到实际应用。     

干扰抵消型多用户检测器性能分析

用模块化的方法描述了 ＳＩＣ、ＭＳＳＩＣ、ＰＩＣ和ＰＳＩＣ干扰抵消多用户检测算法，给出算法的实现结构图，并且在渐近有效性、抗远近效应、系统容量和实现复杂度诸方面进行了性能比较分析。分析表明需要进行功率排序的ＭＳＳＩＣ、ＰＳＩＣ和ＳＩＣ算法比ＰＩＣ算法具有更好的抗远近效应的性能，ＭＳＳＩＣ和 ＰＳＩＣ算法在渐近有效性和系统容量方面要显著强于ＳＩＣ和ＰＩＣ算法。     

空间机器人姿态与末端抓手协调运动的鲁棒自适应控制

本文讨论了载体姿态受控、位置不受控制的漂浮基空间机器人协调运动的控制问题。借助于虚拟扩展系统的输入与输出,得到了一组关于惯性参数呈线性函数关系的系统控制方程。以此为基础,针对空间机器人系统中不确定参数与未知参数并存的复杂情况,设计了载体姿态与末端抓手惯性空间轨迹协调运动的鲁棒自适应控制方案。利用两杆空间机器人系统进行了系统仿真运算,仿真结果证实了上述控制方案的有效性。由于对系统待估计参数作了分类,并充分利用系统信息对系统不确定参数采用保持鲁棒性而不是在线估计的方法,提到的控制方案具有计算量小的优点,有助于缓解机载计算机运算能力有限的矛盾。     

一种新的位置数据融合方法的研究

给出了一新的基于团队一致法的多传感器位置数据融合方法，该方法按传感器队中的每个成员的测量不确定性，构造团队期望效用函数（或密度），并基于该期望效用函数求得位置参数估计，其优点是可消除失效传感器和测量值为野值的传感器的影响，本文给出了仿真结果。     

Spray forming technology for military applications

Over the past five years, the Annapolis Detachment, Carderock Division, Naval Surface Warfare Center (formerly David Taylor Research Center) has established a state- of- the- art spray forming facility for the study and exploitation of this near net shape manufacturing process. Spray forming is a single step gas atomization/deposition process which yields ferrous and nonferrous, near final shape, near fully dense preforms that has proven to be a viable and cost effective alternative to conventional metalworking technology for the production of material preforms with properties surpassing those of their cast and wrought counterparts. Current programs at Carderock Divison Naval Surface Warfare Center are aimed at optimization of the process, certification of the spray formed products and industrialization of the technology.