Development of a practical photogrammetric network design using evolutionary computing     

Gustavo  Olague Enrique  Dunn 《The Photogrammetric Record》2007,22(117):22-38

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5种不同颜色空间的均匀性研究     

廉玉生  王秀泽 《测绘学院学报》2007,(2)

颜色的均匀性是评价颜色空间的优劣和影响其选择使用的重要指标之一,其色差计算值对于颜色再现评价的再现过程控制具有重要作用。在中国颜色体系的基础上,分别从明度、色相和彩度的角度对颜色空间C IEL*a*b*、C IEL*u*v*、NC-IIIC、L*a*b*-N和C IECAM02-UCS的均匀性进行了分析和比较。结果表明,这几种颜色空间明度的均匀性都比较理想,而色相和彩度的均匀性较差。就这5种颜色空间而言,NC-IIIC和L*a*b*-N颜色空间均匀性要优于其他颜色空间。  相似文献   

资源卫星（可见光）遥感数据获取任务调度优化算法研究   总被引：3，自引：0，他引：3  

徐雪仁  宫鹏  黄学智  金勇 《遥感学报》2007,11(1):109-114

从资源卫星（可见光）遥感数据获取任务调度的影响因子分析入手,在研究国外相关遥感任务调度算法的基础上,提出了基于目标的卫星遥感任务调度算法规则,并依据该规则研究建立了算法实现流程,以解决用户需求和星地资源使用约束之间的冲突,从而有效地满足用户对遥感数据的需求。  相似文献   

Cygnus A: stars, dust and cones     

Neal Jackson  Clive Tadhunter  & William B. Sparks 《Monthly notices of the Royal Astronomical Society》1998,301(1):131-141

We present new Hubble Space Telescope ( HST  ) continuum and spectral line images of the radio galaxy Cygnus A. The images show much complex structure in the central kpc². Continuum images show the central dust lane in detail, allowing detailed maps of E ( B  −  V ) to be constructed; the dust appears to follow a roughly Galactic extinction law. The emission-line components are resolved in the line images and investigated in detail. A clear 'opening cone' morphology is found, especially in the lines of Hα and [O  i ]. Blue condensations are seen in the south-eastern emission component and surrounding the central region. These are almost certainly due to star formation, which began <1 Gyr ago as deduced from the colour of the regions. More extended blue continuum is also seen and corresponds to the blue polarized component detected by other recent spectropolarimetric observations.  相似文献   

腐泥煤变质系列热解色谱和氯仿沥青“A”的特点   总被引：2，自引：0，他引：2  

赵海舟 《中国煤田地质》1998,10(2):23-26

对滕县、淄博两煤田与腐殖煤共生的不同煤级的腐泥煤进行了热解和氯仿沥青“Ａ”的族组份分析,获得如下认识：热解的结果,Ｔｍａｘ、Ｓ１、Ｓ３、Ｉｐ全部高于共生腐殖煤,Ｉｔ全部低于共生腐殖煤,Ｓ２和Ｃｐ在低煤化阶段高于腐殖煤,而中,高煤化阶段则低于腐殖煤;氯仿沥青“Ａ”都随煤级的增高而减少,腐泥煤全部高于腐殖煤,腐泥煤从低煤级到高煤级其族组份的排序从饱和烃＞非烃＞芳烃＞沥青质变化到非烃＞芳烃＞沥青质＞饱和烃;而腐殖煤族组份的排序则从沥青质＞芳烃＞非烃＞饱和烃＞沥青质。  相似文献   

Chandra observations of neutron stars: an overview     

M. C. Weisskopf  M. Karovska  G. G. Pavlov  V. E. Zavlin  T. Clarke 《Astrophysics and Space Science》2007,308(1-4):151-160

We present an overview of Chandra X-ray Observatory observations of neutron stars. The outstanding spatial and spectral resolution of this great observatory have allowed for observations of unprecedented clarity and accuracy. Many of these observations have provided new insights into neutron star physics. We present an admittedly biased and overly brief review of these observations, highlighting some new discoveries made possible by the Observatory’s unique capabilities. This includes our analysis of recent multiwavelength observations of the putative pulsar and its pulsar-wind nebula in the IC443 SNR.   相似文献   

美国中东部温带稳定≥10℃积温     

任国玉 《地理研究》1987,6(4):70-76

应用修订的康拉德公式计算美国中东部温带地区日均温稳定≥10℃积温,并同我国相应纬度地区作了对比。这一对比揭示出我国东部温带并非世界同纬度地带夏半年热量资源最丰富。  相似文献   

二噁英类化合物对斑马鱼CYP1 A毒理作用的研究新进展     

聂芳红  刘连平  陈进军  林红英  杨蓉  谢英明 《广东海洋大学学报》2007,27(3):123-128

二噁英类化合物(dioxin-like compounds,DLCs)包括多环芳烃(polycyclic aromatic hydrocar-bons,PAHs)中的多氯代二苯对二噁英(polychlori-nated dibenzo-p-dioxins,PCDDs)、多氯代二苯对呋喃(polychlorinated dibenzofurans,PCDFs)及卤代芳香化合物(halogenated aromatic comp  相似文献   

A fuzzy dynamic flood routing model for natural channels     

R. Gopakumar  P. P. Mujumdar 《水文研究》2009,23(12):1753-1767

A fuzzy dynamic flood routing model (FDFRM) for natural channels is presented, wherein the flood wave can be approximated to a monoclinal wave. This study is based on modification of an earlier published work by the same authors, where the nature of the wave was of gravity type. Momentum equation of the dynamic wave model is replaced by a fuzzy rule based model, while retaining the continuity equation in its complete form. Hence, the FDFRM gets rid of the assumptions associated with the momentum equation. Also, it overcomes the necessity of calculating friction slope (S_f) in flood routing and hence the associated uncertainties are eliminated. The fuzzy rule based model is developed on an equation for wave velocity, which is obtained in terms of discontinuities in the gradient of flow parameters. The channel reach is divided into a number of approximately uniform sub‐reaches. Training set required for development of the fuzzy rule based model for each sub‐reach is obtained from discharge‐area relationship at its mean section. For highly heterogeneous sub‐reaches, optimized fuzzy rule based models are obtained by means of a neuro‐fuzzy algorithm. For demonstration, the FDFRM is applied to flood routing problems in a fictitious channel with single uniform reach, in a fictitious channel with two uniform sub‐reaches and also in a natural channel with a number of approximately uniform sub‐reaches. It is observed that in cases of the fictitious channels, the FDFRM outputs match well with those of an implicit numerical model (INM), which solves the dynamic wave equations using an implicit numerical scheme. For the natural channel, the FDFRM outputs are comparable to those of the HEC‐RAS model. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

G-凸空间内的连续选择定理和重合点定理     

李艳 《成都信息工程学院学报》2007,22(2):274-277

在G-凸空间内得到了一些新的连续选择定理,并利用连续选择定理证明了非紧G-凸空间内及乘积G-凸空间内的重合点定理.这些定理改进并推广了最近文献中的一些已知结果.  相似文献