中古志怪小说女性形象塑造艺术浅析

在人物描写方面，魏晋南北朝志怪小说不像以后的小说那样神形兼备，甚至基本上没有肖像描写，但志怪小说的作者已经开始注意表现所写人物的特定情感和个性，使人物形象具有了一定程度的可感性和生动性。浪漫主义象征性艺术手法、第三人称限知叙事、相对生动细致的细节描写、人物对话、诗歌辞赋的运用以及描写的多样性在一定程度上完成了人物形象塑造和性格揭示，一些优秀篇章中的女性形象塑造，都已达到了生动鲜明、栩栩如生的程度。即便这些只是处在萌芽阶段的尝试，却对后世产生了深远的影响。     

多普勒雷达径向速度资料在对流天气预报中的应用

本文探讨了降水前多普勒天气雷达径向速度资料在对流性天气预报中的应用方法:图像定性分析法及EVAD技术定量分析法。并以2004年5日15时出现在石家庄的对流天气为例,详细介绍了利用这两种方法预报对流天气的步骤。通过对2004年10个对流性天气过程及其对应的径向速度资料的仔细分析,总结出几个定量的利用径向速度资料预报对流天气的指标,对流出现之前:(1)摩擦层开始出现辐合现象,辐合超前对流出现时间平均为8.2 h;(2)1.5°仰角径向速度图像上25 km范围内均出现了距离折叠现象;(3)25 km以内的低层50%出现了E或NE风,其他50%为S到SE风。另外,反查2004年5—6月径向速度资料发现:低层辐合和距离折叠均出现的日期,当天出现对流性降水的几率为77.3%。这些指标对预测预报石家庄地区对流性天气发生发展有一定指示作用,对其它地区也有一定的推广价值。     

赤潮藻的显微图形测量方法研究

介绍了一种在实验室环境下通过显微镜及CCD成像的办法观察采集微小藻类图像，并通过计算机软件进行图像识别统计，最终得到所测藻类统计信息的方法。     

面向真正射影像处理的对象定义及其语义关联

真正射影像作为新一代数字影像产品,其应用需求日益广泛。随着高分辨率倾斜影像的日益可得,逐像素处理的真正射影像生产方法局限性越来越突出。为此,针对面向对象的真正射影像处理,本文提出了物方对象和像方对象的概念,并描述了两类对象间的语义关联关系,并用实例分析了其特殊价值。     

洪涝灾情快速反应的星载SAR与TM数据的融合处理

本文以1998年鄱阳湖地区发生洪涝灾害为研究实例,应用灾中的Radarsat-SAR和灾前的TM数据,以不规则三角网(TIN)方法实现了高精度几何配准。然后,通过波段相关性和信息熵值分析,选取最佳波段。最后,对不同融合模型得出的图像进行对比,得出结论:以灾中的SAR和灾前TM的一个近红外(TM5或TM7)以及一个可见光波段(TM3最佳),分别赋RGB色合成的图像效果很好,既能识别区分洪涝淹没的绝产区、土壤滞水减产区和未受灾区,并且操作简便,能满足洪涝灾情快速反应要求。     

The High Resolution Imaging Science Experiment (HiRISE) during MRO’s Primary Science Phase (PSP)

The High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) acquired 8 terapixels of data in 9137 images of Mars between October 2006 and December 2008, covering ∼0.55% of the surface. Images are typically 5-6 km wide with 3-color coverage over the central 20% of the swath, and their scales usually range from 25 to 60 cm/pixel. Nine hundred and sixty stereo pairs were acquired and more than 50 digital terrain models (DTMs) completed; these data have led to some of the most significant science results. New methods to measure and correct distortions due to pointing jitter facilitate topographic and change-detection studies at sub-meter scales. Recent results address Noachian bedrock stratigraphy, fluvially deposited fans in craters and in or near Valles Marineris, groundwater flow in fractures and porous media, quasi-periodic layering in polar and non-polar deposits, tectonic history of west Candor Chasma, geometry of clay-rich deposits near and within Mawrth Vallis, dynamics of flood lavas in the Cerberus Palus region, evidence for pyroclastic deposits, columnar jointing in lava flows, recent collapse pits, evidence for water in well-preserved impact craters, newly discovered large rayed craters, and glacial and periglacial processes. Of particular interest are ongoing processes such as those driven by the wind, impact cratering, avalanches of dust and/or frost, relatively bright deposits on steep gullied slopes, and the dynamic seasonal processes over polar regions. HiRISE has acquired hundreds of large images of past, present and potential future landing sites and has contributed to scientific and engineering studies of those sites. Warming the focal-plane electronics prior to imaging has mitigated an instrument anomaly that produces bad data under cold operating conditions.     

Saturn’s icy satellites investigated by Cassini-VIMS: II. Results at the end of nominal mission

We report the detailed analysis of the spectrophotometric properties of Saturn’s icy satellites as derived by full-disk observations obtained by visual and infrared mapping spectrometer (VIMS) experiment aboard Cassini. In this paper, we have extended the coverage until the end of the Cassini’s nominal mission (June 1st 2008), while a previous paper (Filacchione, G., and 28 colleagues [2007]. Icarus 186, 259-290, hereby referred to as Paper I) reported the preliminary results of this study.During the four years of nominal mission, VIMS has observed the entire population of Saturn’s icy satellites allowing us to make a comparative analysis of the VIS-NIR spectral properties of the major satellites (Mimas, Enceladus, Tethys, Dione, Rhea, Hyperion, Iapetus) and irregular moons (Atlas, Prometheus, Pandora, Janus, Epimetheus, Telesto, Calypso, Phoebe). The results we discuss here are derived from the entire dataset available at June 2008 which consists of 1417 full-disk observations acquired from a variety of distances and inclinations from the equatorial plane, with different phase angles and hemispheric coverage. The most important spectrophotometric indicators (as defined in Paper I: I/F continua at 0.55 μm, 1.822 μm and 3.547 μm, visible spectral slopes, water and carbon dioxide bands depths and positions) are calculated for each observation in order to investigate the disk-integrated composition of the satellites, the distribution of water ice respect to “contaminants” abundances and typical regolith grain properties. These quantities vary from the almost pure water ice surfaces of Enceladus and Calypso to the organic and carbon dioxide rich Hyperion, Iapetus and Phoebe. Janus visible colors are intermediate between these two classes having a slightly positive spectral slope. These results could help to decipher the origins and evolutionary history of the minor moons of the Saturn’s system. We introduce a polar representation of the spectrophotometric parameters as function of the solar phase angle (along radial distance) and of the effective longitude interval illuminated by the Sun and covered by VIMS during the observation (in azimuth) to better investigate the spatial distribution of the spectrophotometric quantities across the regular satellites hemispheres. Finally, we report the observed spectral positions of the 4.26 μm band of the carbon dioxide present in the surface material of three outermost moons Hyperion, Iapetus and Phoebe.     

In-flight calibration of the Cassini imaging science sub-system cameras

We describe in-flight calibration of the Cassini Imaging Science Sub-system narrow- and wide-angle cameras using data from 2004 to 2009. We report on the photometric performance of the cameras including the use of polarization filters, point spread functions over a dynamic range greater than 10⁷, gain and loss of hot pixels, changes in flat fields, and an analysis of charge transfer efficiency. Hot pixel behavior is more complicated than can be understood by a process of activation by cosmic ray damage and deactivation by annealing. Point spread function (PSF) analysis revealed a ghost feature associated with the narrow-angle camera Green filter. More generally, the observed PSFs do not fall off with distance as rapidly as expected if diffraction were the primary contributor. Stray light produces significant signal far from the center of the PSF. Our photometric analysis made use of calibrated spectra from eighteen stars and the spectral shape of the satellite Enceladus. The analysis revealed a shutter offset that differed from pre-launch calibration. It affects the shortest exposures. Star photometry results are reproducible to a few percent in most filters. No degradation in charge transfer efficiency has been detected although uncertainties are large. The results of this work have been digitally archived and incorporated into our calibration software CISSCAL available online.     

两种快速星像匹配算法的比较

星像的位置和亮度等信息对天文研究和空间导航具有基础意义。人们常常需要快速匹配从密集星场CCD图像中提取的信息来获取与星表中对应的信息(如位置、光度等),因此开发出了多种星像匹配算法。重点比较了两种最新的星像匹配算法:i)基于向量的方法;ii)基于径向和环向特征的方法。通过对云南天文台1m望远镜观测的CCD图像进行实际匹配,结果表明基于向量的方法更优,它是一种快速的、接近常数时间的匹配算法。     

ePSF拟合法与Gaussian拟合法的比较

为了解决哈勃空间望远镜的图像欠采样问题,美国学者Anderson和King提出了精确测量星像位置和通量的有效点扩散函数(ePSF—effective point-spread function)拟合法。然而,他们却不加比较地将其应用于地面CCD图像中星像的位置高精度测量。因此,我们试图将ePSF拟合法与经典的高斯函数(Gaussian)拟合法作比较研究。调用CFITSIO库生成模拟的背景图像,并应用不同参数条件下的星像轮廓模型产生非欠采样的星像。最后,分别采用ePSF拟合法与Gaussian拟合法对这些星像进行拟合,并对它们的拟合精度进行比较。实验结果表明,在非欠采样的图像中这两种算法对星像位置的测量几乎是等精度的。