MFE跨隔-射孔测试技术在青西油田负压井上的应用分析

跨隔-射孔测试联作是利用跨隔的方式对试油目的层进行射孔、测试联作的新型综合试油工艺,能够缩短试油周期,提高施工效率。根据该项工艺在玉门青西油田应用情况分析,在肯定工艺优点的同时,针对在某些负压井上出现的泄压现象,提出了工艺改进建议,以使之具有更加广泛的适用性。     

某框架结构基础柱承载力鉴定

本文介绍了参照基桩桩身承载力计算原理考虑土的侧向约束对埋入地下的基础柱承载能力验算的一种思路，可为该类构件承载能力鉴定提供一些参考。     

茂金属乙烯－辛烯共聚物弹性体的应用

综述了茂金属乙烯－辛烯共聚物作为弹性体系材料的最新应用进展,采用藏属催化剂合成的乙烯－辛烯共聚物是一咎新型热塑性弹性体,可用注射,挤出,吹塑等常用加工方法成型,又可用过氧化物进行化学交联,用橡胶加工方法制成弹性体材料。     

一般多边形网格的几何压缩

提出一个通用的一般多边形网格的几何压缩算法，针对目前三维拓扑压缩算法大都仅适用于三角网格的现状，在巳有算法的基础上，进行了有效的推广，使得对于包含任意边数多边形的网格都可以进行有效的压缩编码；另外，根据多边形网格任一多边形中的各个顶点共面的特性，提出一种顶点坐标压缩方案，该方案与上述拓扑压缩算法有机结合可以显著地减少一般多边形网格数据在网上传输所需的带宽；最后，对编码过程产生的输出流进行流程编码与算术编码相结合的混合压缩编码，从而进一步提高压缩比。     

VB下识别有机煤岩显微镜图片

在煤的有机岩石学中,镜下和照片中显微组分的识别是一件重要而又特别耗眼睛的工作。本文利用煤显微组分在镜下不同颜色显现的特点,用计算机VB编程对煤的三大显微组分进行灰度识别。     

Direct 3D Painting with a Metaball-Based Paint brush

1IntroductionComputertechnologyisnowchangingtheformandfunctionoftraditionalart.Oneinspiringaspectamongmostapplicationsinthefieldofartinvolvingcomputergraphicsisdigitalpainting.Aninteractivepaintsystemallowsanartisttoworkonasingleimage['].Whitteddescr...     

红外目标与背景的真实感合成

目标与地面背景的真实感红外图像合成是红外场景生成和实现其虚拟实时漫游的关键技术。文中从传热学原理出发，综合考虑各种环境因素的影响，建立起地面目标（如坦克）的热传导模型，绘制出坦克在各种状态下的红外图像。根据计算出的坦克和地面接触后达到热平衡时的温度场分布，绘制出真实感较强的坦克与背景的红外合成图像。利用三维差分法计算并绘制出坦克离去后留下的“红外阴影”效果，即地面因原有目标强烈辐射而留下的高于周围区域的温度场分析，并绘制出坦克驶离后不同时刻地面背景灰度及彩色的红外图像，为倒推某时刻之前红外目标的存在提供了依据。     

基于深度网格的大规模森林场景的动态模拟

为了降低大规模森林场景的数据量和较真实地模拟其在风力作用下的动态效果,提出一种完全基于GPU的森林场景动态模拟方法.首先采用一种基于深度图像并重建几何的方法对树模型进行优化,在优化后的模型中内建了多个层次细节,并进行有效的压缩;然后采用随机过程的方法对风场建模,用简化的过程式方法计算风力作用下树的位移和形变.实验结果表明,该方法可以实现以8 MB存储空间和85 MB显存空间为代价、实时模拟数量高达10万棵的大规模森林场景在风场作用下的动态效果,且模拟效果好、质量高.     

Precomputed Radiance Transfer Field for Rendering Interreflections in Dynamic Scenes

In this paper, we introduce a new representation – radiance transfer fields (RTF) – for rendering interreflections in dynamic scenes under low frequency illumination. The RTF describes the radiance transferred by an individual object to its surrounding space as a function of the incident radiance. An important property of RTF is its independence of the scene configuration, enabling interreflection computation in dynamic scenes. Secondly, RTFs naturally fit in with the rendering framework of precomputed shadow fields, incurring negligible cost to add interreflection effects. In addition, RTFs can be used to compute interreflections for both diffuse and glossy objects. We also show that RTF data can be highly compressed by clustered principal component analysis (CPCA), which not only reduces the memory cost but also accelerates rendering. Finally, we present some experimental results demonstrating our techniques.     

Shading with Curve Light Sources1

A new shading model for curve light sources is presented. It accounts for both diffuse reflection and specular reflection of the illuminated surface. By regarding a linear light source as a directional quadrilateral light source with very small width, a simple formula is derived first for calculating the diffuse reflection component due to the illumination of the linear segment. The diffuse reflection of the surface by direct illumination of a curve light source is then evaluated by approximating the curve light with a series of linear segments. The specular reflection component due to a curve light source is represented by an integration taking Phong's specular model as the kernel and evaluated by summing the contributions from the linear segments. Finally, an efficient shadow detection algorithm for curve light sources is proposed. The images rendered with the shading model are very photo-realistic.