An efficient hierarchicaltraversal algorithm for ray tracing

Ray tracing has been shown to be an excellent technique for rendering realistic images. However, it is important to reduce the lengthy computation time resulting from the brute-force nature of the original ray-tracing algorithms. In this paper, two ideas are proposed to speep up the well-known hierarchical subdivision method. First, a new hierarchy traversal scheme is described to reduce the number of raybounding volume intersection tests for secondary rays. Then, a plane-sweep method is proposed to make fewer intersection checks for eye rays. Experiments and discussions are presented to prove the feasibility of our methods.     

ATM局域网仿真技术

本文介绍了ＡＴＭ局域网仿真技术并从ＡＴＭ仿真局网的组成、工作原理等方面介绍了这一技术的主要特点。     

Deformation analysis of skew ruled surface shells by moiré interference

The use of thin film grids coated on surfaces is described in relation to the determination of deformations in doubly curved shells. The technique is called the coating film moiré interference method and employs a laser holographic approach.     

济钢中板厂加快技术创新的对策

本文通过对中板厂近年来技术改造后工艺装置和技术水平的分析，并结合中国加入WTO后对中国钢铁企业面临全球化市场竞争严峻性的认识，提出了中板厂在实现高产生产模式后，应加快技术创新的步伐，尽快完成由高产向优质、多品种、低消耗的高效化生产模式转化的主导思想、措施及建议。     

Continuous Separation of Inclusions from Aluminum Melt Flowing in a Circular Pipe using a High Frequency Magnetic Field

The continuous separation of inclusions from aluminum melt flowing in a circular pipe using a high frequency magneticfield was investigated both theoretically and experimentally The separation efficiency was calculated based on thetrajectory method and compared with experimental results. It is found that the separation efficiency is a functilnondimensional parameters t_i·d_p~2B_e~2/μ_fμ_eα~2 and α/δ.The effective way to improve the separation efficiency is to increasethe effective magnetic flux density and decrease the pipe radius. and the value of α/δ should be kept about 2 in orderto obtain the optimum separation efficiency.     

新抗生素B-3543的研究

对新抗生素B-3543进行了系统的研究,关键指标已达到工业化生产水平。确立了产生菌的分类地位,测定了抗生素的抗菌谱,获得效价达10000μg/ml的高产菌株,阐明了B-3543的化学结构,提出3种效价检定方法,制定了产品质量标准,完善了生产工艺,使产品总收率达60％。该项目还存在产品成本过高,产品稳定性不好等问题,有待研究解决。     

地图中铁路、道路提取和恢复显示的方法

本文提出一种从军用地图中提取铁路、道路的半自动方法和自动恢复显示其在地图中标识方式的算法,从而进一步实现地图图形显示系统的多层次结构。     

SNCP环带链的组网与维护

在实际传输网络结构中,有些站点由于条件限制不能与其它站点连接成环.过去采用通道保护(PP)环带链组网,环链网元间业务在环上没有保护;随着技术的发展,提出了子网连接保护(SNCP)环带链组网方式,确保环链网元间业务在环上得到保护,使网络的稳定性和可靠性大大提高.     

节理岩体的代表单元集合体模型及弹性参数预测

本文明确提出了节理岩体“代表单元集合体”的概念和模型，通过对节理岩体的“代表单元集合体”进行数值模拟，研究了节理岩体的“代表单元集合体”的变形特性，建立了节理岩体的弹性模型，提出了预测节理岩体宏观等效弹性参数的计算机模拟方法，并将其应用于岩体工程稳定性分析中。