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The change of impervious surface area (ISA) can effectively reveal the gradual process of urbanization and act as a key index for monitoring urban expansion. Experiencing rapid growth of the built environment in the 2000s, urban expansion of Beijing has not been fully characterized through ISA. In this study, Landsat TM images of Beijing in 2001 and 2009 were obtained, and the eight-year urban expansion process in Beijing was analyzed using the ISA extracted by means of the vegetation-imperious surface-soil (V-I-S) model. From the spatial variation in ISA, the ring structure of urban expansion in Beijing was significant during the study period, with decreasing urban density from the city center to the periphery. In the ring road analysis, the most dramatic changes of ISA were found between the fifth ring and the sixth ring. This area has experienced the most new residential development, and is currently the main source of urban expansion. The typical profile lines revealed the directional characteristics of urban expansion. The east-west profile was the most urbanized axes in Beijing, while ISA change in the east-north profile was more significant than in the other five profiles. Moreover, the transition matrix of ISA levels revealed an increase in urban density in the low density built areas; the Moran′s I index showed a clear expansion of the central urban area, which spread contiguously; and the standard deviational ellipse indicated the northeast was the dominant direction of urban expansion. These findings can provide important spatial control guidelines in the next round of national economic and social development planning, overall urban and rural planning, and land use planning.

Longitudinal cracks are common defects of continuous casting slabs and may lead to serious quality accidents. Image capturing and recognition of hot slabs is an effective way for on-line detection of cracks, and recognition of cracks is essential because the surface of hot slabs is very complicated. In order to detect the surface longitudinal cracks of the slabs, a new feature extraction method based on Curvelet transform and kernel locality preserving projections (KLPP) is proposed. First, sample images are decomposed into three levels by Curvelet transform. Second, Fourier transform is applied to all sub-band images and the Fourier amplitude spectrum of each sub-band is computed to get features with translational invariance. Third, five kinds of statistical features of the Fourier amplitude spectrum are computed and combined in different forms. Then, KLPP is employed for dimensionality reduction of the obtained 62 types of high-dimensional combined features. Finally, a support vector machine (SVM) is used for sample set classification. Experiments with samples from a real production line of continuous casting slabs show that the algorithm is effective to detect longitudinal cracks, and the classification rate is 91.89%.

Optical molecular imaging is an important technique of studies at molecular level and provides promising tools to non-invasively delineate in vivo physiological and pathological activities at cellular and molecular levels, and it has been widely used for diagnosing, managing diseases, metastasis detection and drug development. From a mathematical perspective, this paper mainly focuses on the forward problem and inverse problem in biological tissues based on the radiative transfer equation （RTE）. The forward problem is accustomed to describing photon propagation in biological tissues and the inverse problem is used to reconstruct internal source distribution from the signal detected on the external surface. We also introduce the detailed derivation of the RTE and Robin boundary condition and discretization of the forward problem, along with the reconstruction methods and iterative solution algorithms summarized for the inverse problem. Finally, the current and future challenges of optical molecular imaging are discussed. This survey aims to construct a mathematical method, a state-of-the-art framework for optical molecular imaging, from which future research may benefit.

In order to archive, quality control and disseminate a large variety of marine data in a marine data exchange platfonn, a marine XML has been developed to encapsulate marine data, which provides an efficient means to store, transfer and display marine data. This paper first presents the details of the main marine XML elements and then gives an example showing how to transform CTD-observed data into Marine XML format, which illustrates the XML encapsulation process of marine observed data.

围绕低空多镜头倾斜摄影在三维城市影像模型生产中的纹理优化问题,提出了一种无缝纹理模型重建方法。文中首先采用相机响应函数和暗通道方法对影像进行预处理;然后,根据地物三角网格表面模型与影像的映射关系,利用稀疏构网方法进行遮挡检测,并建立了三角面片的可视纹理列表;最后,结合三角网格表面模型中基本面片的三维拓扑关系,利用影像的均值与方差信息,构建了基于马尔科夫随机场框架下的图割纹理优化算法,解决了纹理优化选择的离散多标号问题,保证了相邻三角面片映射纹理的一致性,实现了城市大场景无缝纹理模型的重建。试验结果验证了算法的可靠性和优越性。

物体表面三维测量技术已广泛应用于文物数字化保护、逆向工程、产品质量检测等领域.使用已得到广泛应用的非接触式三维测量技术对复杂物体进行重建时,通常会受到测量条件和测量环境的限制,从而会产生由于轮廓遮挡（扫描盲区）引起的表面点云空洞,使得最终生成的物体表面点云模型不完整.

Fas及其配体FasL与肿瘤发生发展的关系近年来受到关注。Fas为Ⅰ型跨膜糖蛋白，属肿瘤坏死因子受体家族（TNFR）及神经生长因子受体家族（NGFR），表达于人记忆T细胞、NK细胞及成熟T、B细胞上。FasL是Ⅱ型跨膜糖蛋白，与TNFR家族有同源性，表达于活化的T细胞、NK细胞及多种肿瘤细胞表面。FasL与Fas结合后，传导凋亡信号，诱导Fas阳性细胞发生凋亡。Fas有两种形式：细胞表面的膜型Fas（mFas）和血清可溶性Fas（sFas）。mFas可与FasL结合激发Fas阳性细胞凋亡，sFas可与FasL竞争结合而抑制Fas途径介导的凋亡，因此可认为sFas是一种新的免疫抑制因子。