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71.
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73.
张谦 《计算机应用与软件》1998,15(6):27-29
本文提出了的改进的Phong浓淡处理技术,无须对多边形进行任何预处理,通过对漫反射明暗度和表面法矢及H矢量的双线性插值,保证了显示效果,并将算法效率提高35~40%。 相似文献
74.
Fast Hybrid Approach for Texturing Point Models 总被引:1,自引:0,他引:1
We present three methods for texturing point models from sample textures. The first method, the point parameterization method, uses a fast distortion‐bounded parameterization algorithm to flatten the point model's surface into one or more 2D patches. The sample texture is mapped onto these patches and alpha blending is used to minimize the discontinuity in the gaps between the patches. The second method is based on neighborhood matching where a color is assigned to each point by searching the best match within an irregular neighborhood. The hybrid method combines the former two methods, capitalizing on the advantages of both. The point parameterization method is used first to color most of the points, and the point neighborhood‐matching method is then applied to the points belonging to the gaps between the parameterized patches to minimize the discontinuity. We opt for fast texture generation, while some discontinuities may appear in the gaps of anisotropic textures. 相似文献
75.
M.?A.?Kabir M.?M.?K.?KhanEmail author M.?A.?Bhuiyan 《Journal of Mechanical Science and Technology》2003,17(6):879-887
The flow ina parallel walled test channel, when obstructed with a geometry at the entrance, can be forward, reverse and stagnant depending
on the position of the obstruction. This interesting flow phenomenon has potential benefit in the control of energy and various
flows in the process industry. In this experiment, the flat plate obstruction geometry was used as an obstruction at the entry
of the test channel. The parameters that influence the flow inside and around the test channel were the gap (g) between the
test channel and the obstruction geometry, the length (L) of the test channel and the Reynolds number (Re). The effect of
the gap to channel width ratio (g/w) on the magnitude of the velocity ratio (V1/V0 : velocity inside/ velocity outside the test channel) was investigated for a range of Reynolds numbers. The maximum reverse
flow observed was nearly 20% to 60% of the outside velocity for Reynolds number ranging from 1000 to 9000 at g/w ratio of
1.5. The maximum forward velocity inside the test channel was found 80% of the outside velocity at higher g/w ratio of 8.
The effect of the test channel length on the velocity ratio was investigated for different g/w ratios and a fixed Reynolds
number of 4000. The influence of the Reynolds number on the velocity ratio is also discussed and presented for different gap
to width ratio (g/w). The flow visualisation photo-graphs showing fluid motion inside and around the test channel are also
presented and discussed. 相似文献
76.
通过分析了重介质系统管路中平板闸阀存在的问题,提出了延长平板闸阀的使用寿命的措施为:设计合理的结构和选择适当的材料.实践证明:该结果是可行的. 相似文献
77.
Jong-Hark?Park Seong-Yeon?YooEmail author 《Journal of Mechanical Science and Technology》2004,18(7):1258-1266
It is important to completely understand heat/mass transfer from a flat plate because it is a basic element of heat/mass transfer.
In the present study, local heat/mass transfer coefficient is obtained for two flow conditions to investigate the effect of
boundary layer using the naphthalene sublimation technique. Obtained local heat/mass transfer coefficient is converted to
dimensionless parameters such as Sherwood number, Stanton number and Colburnj-factor. These also are compared with correlations of laminar and turbulent heat/mass transfer from a flat plate. According
to experimental results, local Sherwood number and local Stanton number are in much better agreement with the correlation
of turbulent region rather than laminar region, which means analogy between heat/mass transfer and momentum transfer is more
suitable for turbulent boundary layer. But average Sherwood number and average Colburnj-factor representing analogy between heat/mass transfer and momentum transfer are consistent with the correlation of laminar
boundary layer as well as turbulent boundary layer. 相似文献
78.
79.
蔡碧新 《福建建筑高等专科学校学报》2011,(6):574-578
建筑节能应从方案创作阶段予以重视。文章以福州地区某高校新区食堂为例,在分析福州地区气候特点及日照的基础上,给出了福州地区建筑方案创作阶段建筑物的适宜朝向及建筑的最佳体形设计建议,提出了福州地区建筑遮阳设计方法以及如何合理组织建筑的自然通风等多项建筑节能设计策略。 相似文献
80.
壁面纵向沟槽减阻的实验研究 总被引:2,自引:1,他引:2
平板表面开V形纵向沟槽,与光滑板进行流动阻力对比试验,结果表明,表面开沟槽以后具有明显的减阻效果,其减阻程度取决于表面所开纵向沟槽的几何特性。在实验范围内,01mm沟槽减阻效果最佳,减阻率可达10%。 相似文献