Comparison of two scaling approaches for the development of biomechanical multi-body human models

Dimensional scaling approaches are widely used to develop multi-body human models in injury biomechanics research. Given the limited experimental data for any particular anthropometry, a validated model can be scaled to different sizes to reflect the biological variance of population and used to characterize the human response. This paper compares two scaling approaches at the whole-body level: one is the conventional mass-based scaling approach which assumes geometric similarity; the other is the structure-based approach which assumes additional structural similarity by using idealized mechanical models to account for the specific anatomy and expected loading conditions. Given the use of exterior body dimensions and a uniform Young’s modulus, the two approaches showed close values of the scaling factors for most body regions, with 1.5 % difference on force scaling factors and 13.5 % difference on moment scaling factors, on average. One exception was on the thoracic modeling, with 19.3 % difference on the scaling factor of the deflection. Two 6-year-old child models were generated from a baseline adult model as application example and were evaluated using recent biomechanical data from cadaveric pediatric experiments. The scaled models predicted similar impact responses of the thorax and lower extremity, which were within the experimental corridors; and suggested further consideration of age-specific structural change of the pelvis. Towards improved scaling methods to develop biofidelic human models, this comparative analysis suggests further investigation on interior anatomical geometry and detailed biological material properties associated with the demographic range of the population.     

k-Multi-preference query over road networks

Nowadays, the road network has gained more and more attention in the research area of databases. Existing works mainly focus on standalone queries, such as k-nearest neighbor queries over a single type of objects (e.g., facility like restaurant or hotel). In this paper, we propose a k-multi-preference (kMP) query over road networks, involving complex query predicates and multiple facilities. In particular, given a query graph, a kMP query retrieves of the top-k groups of vertices (of k facility types) satisfying the label constraints and their aggregate distances are the smallest. A naïve solution to this problem is to enumerate all combinations of vertices with k possible facility types and then select the one with the minimum sum distance. This method, however, incurs rather high computation cost due to exponential possible combinations. In addition, the existing solutions to other standalone queries are for a single type of facilities and cannot be directly used to answer kMP queries. Therefore, in this paper, we propose an efficient approach to process a kMP query, which utilizes an index with bounded space and reduces the computation cost of the shortest path queries. We also design effective pruning techniques to filter out false alarms. Through our extensive experiments, we demonstrate the efficiency and effectiveness of our proposed solutions.     

基于改进粒子群优化算法的火电厂机组负荷分配

以坑口电厂厂级监控信息系统的机组负荷在线优化分配功能模块为应用背景,针对模块所运用的基本粒子群优化算法在优化过程中容易陷入局部收敛、收敛速度慢的缺点,提出一种基于惯性权重非线性减小策略的改进粒子群优化算法,使惯性权重呈对数减小;测试函数仿真结果表明,改进粒子群优化算法在收敛速度和寻优精度方面,优化性能均优于基本粒子群优化算法;通过MATLAB与Visual C++混合编程,开发了机组负荷在线优化分配功能模块,提高了算法的计算效率和工程应用价值。     

Bidirectional controlled quantum teleportation and secure direct communication using five-qubit entangled state

A scheme is presented to implement bidirectional controlled quantum teleportation (QT) by using a five-qubit entangled state as a quantum channel, where Alice may transmit an arbitrary single qubit state called qubit A to Bob and at the same time, Bob may also transmit an arbitrary single qubit state called qubit B to Alice via the control of the supervisor Charlie. Based on our channel, we explicitly show how the bidirectional controlled QT protocol works. By using this bidirectional controlled teleportation, espcially, a bidirectional controlled quantum secure direct communication (QSDC) protocol, i.e., the so-called controlled quantum dialogue, is further investigated. Under the situation of insuring the security of the quantum channel, Alice (Bob) encodes a secret message directly on a sequence of qubit states and transmits them to Bob (Alice) supervised by Charlie. Especially, the qubits carrying the secret message do not need to be transmitted in quantum channel. At last, we show this QSDC scheme may be determinate and secure.     

高职计算机应用基础课程实训教学改革的探索与实践

根据高等职业教育的培养目的和教学特点以及非计算机专业《计算机应用基础》课程实践教学标准的要求,文章从加强《计算机应用基础》课程的实训教学出发,根据学生的不同专业和实际情况,探讨了加强实训教学的方法和科学合理检查和评价学生的方法,总结了《计算机应用基础》课程在高职教育教学改革中一些行之有效的经验,全面提高学生的计算机实际应用能力。     

相交过渡的识别与抑制算法

通过分析相交过渡识别与抑制的难点,提出一种简单高效的相交过渡识别与抑制算法.该算法基于过渡抑制前后尖边的去留状态预测模型的拓扑变化,实现相交过渡的识别与抑制:对过渡面的尖边进行分类,将其分为删除边、保留边和分割保留边3类;基于分类结果,将含有保留边的过渡识别为相交过渡;根据相交过渡中尖边所对应的过渡抑制后的拓扑变化重构过渡周围面边界,实现相交过渡抑制.实验结果表明,文中算法能快速、有效地简化相交过渡,具有较高的效率和较强的鲁棒性.     

异构CAD系统间的用户自定义特征在线交换

用户自定义特征(UDF)能很好地反映用户特有的设计意图,减少重复性的设计活动,是主流CAD系统都提供的功能,因此实现UDF在线交换是异构CAD系统在线集成中不可或缺的一部分.为此,提出一种基于中性命令的UDF在线交换方法.在综合主流CAD系统UDF表示的基础上,给出了一种UDF的中性命令表示;然后给出系统UDF与中性UDF命令之间的相互转换算法,并重点介绍了其中的差异性解决方法.采用文中方法在Pro/E,SolidWorks和UG之间进行UDF实时交换的实例结果表明,文中提出的UDF在线交换方法能够有效地支持UDF在异构CAD系统间的实时创建、修改和删除操作.     

基于B/S结构的高校教学管理信息系统的实现

教学管理信息系统的建立可以确保学校教学数据的一致性,实现数据信息资源的分级共享,替代原始的纸张流转。通过计算机和网络系统得以规范教务管理流程、学生管理流程。本文结合目前高等院校教学特点,介绍如何利用对象关系映射技术（ORM）构建B/S三层模式的教学管理信息系统。