膛阻与小口径弹道炮弹道特性变化的分析

小口径弹道炮在使用初期,弹道特性值偏高,影响产品的验收和标准弹的鉴选.该文用膛阻理论解释弹道炮使用的各个时期的弹道特性变化,并介绍了“光膛”射击后,在弹道曲线下降段进行产品验收以及标准弹鉴选中的实际应用.     

Handling degenerate cases in exact geodesic computation on triangle meshes

The computation of exact geodesics on triangle meshes is a widely used operation in computer-aided design and computer graphics. Practical algorithms for computing such exact geodesics have been recently proposed by Surazhsky et al. [5]. By applying these geometric algorithms to real-world data, degenerate cases frequently appear. In this paper we classify and enumerate all the degenerate cases in a systematic way. Based on the classification, we present solutions to handle all the degenerate cases consistently and correctly. The common users may find the present techniques useful when they implement a robust code of computing exact geodesic paths on meshes.     

2007年1-9月主要钢铁产品进出口形势分析

2007年前三季度,我国的粗钢产量达到36273.2万吨,同比增长17.61%;钢材产量达41753.83万吨(含重复材),同比增长23.97%。前三季度,我国的钢材出口虽保持在较高位,但出口增幅较最高点的4月份大幅度下滑了59个百分点,与年初出口量持胡     

2007年1-10月主要钢铁产品进出口形势分析

2007年1-10月,我国的粗钢产量达到4.09亿吨,同比增长18.14%。10月单月产量4292.2万吨,再创单月产量新高;1-10月,钢材产量达4.67亿吨(含重复材),同比增长23.53%,10月钢材产量     

Real-time homogenous translucent material editing

This paper presents a novel method for real-time homogenous translucent material editing under fixed illumination. We consider the complete analytic BSSRDF model proposed by Jensen et al. [ [JMLH01] ], including both multiple scattering and single scattering. Our method allows the user to adjust the analytic parameters of BSSRDF and provides high-quality, real-time rendering feedback. Inspired by recently developed Precomputed Radiance Transfer (PRT) techniques, we approximate both the multiple scattering diffuse reflectance function and the single scattering exponential attenuation function in the analytic model using basis functions, so that re-computing the outgoing radiance at each vertex as parameters change reduces to simple dot products. In addition, using a non-uniform piecewise polynomial basis, we are able to achieve smaller approximation error than using bases adopted in previous PRT-based works, such as spherical harmonics and wavelets. Using hardware acceleration, we demonstrate that our system generates images comparable to [ [JMLH01] ]at real-time frame-rates.     

动态Cache技术在网站性能设计中的应用

本文主要讲述如何利用Cache技术,来有效的提高网站性能。以ASP.NET为基础,展示ASP.NET中使用Cache的新特性,主要应用了Databasedependencies技术。     

利用模糊评判方法确定张东构造油藏储量计算的可靠程度

张巨河油田张东构造地处大港滩海交接处,海域部分探井少.目前用油藏描述方法计算的探明储量,其落实程度备受关注.储量落实程度的评价是一个多因素综合评判问题,而且这些因素还分属不同层次.模糊综合评判是应用较为广泛的模糊数学方法之一.该方法建立的综合评判涉及三个要素,即因素集、评判集和单因素评判,由此所构造的模糊评判关系是模糊综合评判的基础.本文用该方法对张东构造沙二段油藏的探明储量落实程度作了尝试性评价.     

基于自组织神经网络的实时统计特征抽取方法

应用人工神经网络讨论统计了特征抽取的原理，提出了相应的抽取方法。该方法具有实时性，容错性，高数据压缩率和良好的特征分辨率。通过计算机仿真和桥梁索力状态的实例计算分析证实了该技术具有广泛的应用价值。