The Design and Implementation of "The GIS Based Mineral Resource Management Information System"

本文详细描述了运用软件工程原理、地理信息系统技术和数据库分析技术等开发"基于GIS技术的矿产资源管理信息系统"的全过程.该系统实现了地质资料数据的标准化存储管理以及方便快捷的查询检索和可视化分析处理,为进一步实现地矿资料数据的深层次开发利用打下坚实的基础.     

时态关系数据的特征及其规范化

本文研究了时态关系数据的特征 ,给出了时态范式关系模式的定义 ,简述了其规范化过程 .     

Stable self-attention adversarial learning for semi-supervised semantic image segmentation

The application of adversarial learning for semi-supervised semantic image segmentation based on convolutional neural networks can effectively reduce the number of manually generated labels required in the training process. However, the convolution operator of the generator in the generative adversarial network (GAN) has a local receptive field, so that the long-range dependencies between different image regions can only be modeled after passing through multiple convolutional layers. The present work addresses this issue by introducing a self-attention mechanism in the generator of the GAN to effectively account for relationships between widely separated spatial regions of the input image with supervision based on pixel-level ground truth data. In addition, the adjustment of the discriminator has been demonstrated to affect the stability of GAN training performance. This is addressed by applying spectral normalization to the GAN discriminator during the training process. Our method has better performance than existing full/semi-supervised semantic image segmentation techniques.     

全卷积神经网络的字符级文本分类方法

传统卷积神经网络文本分类模型全连接层参数过多易引发过拟合问题,为此,将图像分割中的全卷积思想首次引入字符级文本分类任务中,不仅避免了过拟合问题,而且通过卷积层替换全连接层减少了参数数量,从而加快了模型收敛速度。文本分类问题中单词、短语等层面的处理方式存在获取文本信息不充分的问题。使用字符级全卷积神经网络进行文本分类,充分获取文本信息,并在卷积池化层后添加局部响应归一化层（LRN）,提高了模型的总体性能。通过使用多指标在测试数据集中进行模型评估,充分验证了该模型的有效性,与其他模型相比,提出的模型在二分类与多分类任务中具有更好的分类性能。     

Normalization approaches for the descent search direction in isogeometric shape optimization

In isogeometric shape optimization, the use of the search direction directly predicted from the discrete shape gradient makes the optimization history strongly dependent on the discretization. This discretization-dependency can affect the convergence and may lead the optimization process into a sub-optimal solution. The source of this discretization-dependency is traced to the lack of consistency with the local steepest descent search direction in the continuous formulation. In the present contribution, this inconsistency is analyzed using the shape variation equations and subsequently illustrated with a volume minimization problem. It is found that the inconsistency originates from the NURBS discretization which induces a discrete quadratic norm to represent the continuous Euclidean norm. To fix this inconsistency, three normalization approaches are proposed to obtain a discretization-independent normalized descent search direction. The discretization-independence of the proposed approaches is verified with a benchmark problem. The superiority of the proposed search direction and its suitability for numerical implementation is illustrated with examples of shape optimization for mechanical and thermal problems. Although the present work focuses on a NURBS-based discretization usually used in conjunction with isogeometric analysis, the proposed methodology may also be applied to alleviate the “mesh-dependency” in (traditional) Finite Element-based shape optimization.     

多模态生物特征识别技术进展综述

近年来,生物特征识别已经成为一种最具潜力的身份认证技术之一.主要对多模态生物特征识别技术进行概括和总结,同时也介绍了现存若干用于身份识别和验证的多模态生物特征识别系统.经调查研究显示,多模态生物特征识别技术由于在身份认证和识别过程中考虑了个体的多种生理或行为特征,因而表现出了较单生物特征更高的可靠性和安全性,并已成为生物特征识别技术未来发展的趋势之一.     

Distortion-free predictive streaming time-series matching

Efficient processing of streaming time-series generated by remote sensors and mobile devices has become an important research area. As in traditional time-series applications, similarity matching on streaming time-series is also an essential research issue. To obtain more accurate similarity search results in many time-series applications, preprocessing is performed on the time-series before they are compared. The preprocessing removes distortions such as offset translation, amplitude scaling, linear trends, and noise inherent in time-series. In this paper, we propose an algorithm for distortion-free predictive streaming time-series matching. Similarity matching on streaming time-series is saliently different from traditional time-series in that it is not feasible to directly apply the traditional algorithms for streaming time-series. Our algorithm is distortion-free in the sense that it performs preprocessing on streaming time-series to remove offset translation and amplitude scaling distortions at the same time. Our algorithm is also predictive, since it performs streaming time-series matching against the predicted most recent subsequences in the near future, and thus improves search performance. To the best of our knowledge, no streaming time-series matching algorithm currently performs preprocessing and predicts future search results simultaneously.     

A feature-based robust digital image watermarking against geometric attacks

Based on scale space theory and an image normalization technique, a new feature-based image watermarking scheme robust to general geometric attacks is proposed in this paper. First, the Harris–Laplace detector is utilized to extract steady feature points from the host image; then, the local feature regions (LFR) are ascertained adaptively according to the characteristic scale theory, and they are normalized by an image normalization technique; finally, according to the predistortion compensation theory, several copies of the digital watermark are embedded into the nonoverlapped normalized LFR by comparing the DFT mid-frequency magnitudes. Experimental results show that the proposed scheme is not only invisible and robust against common signals processing methods such as median filtering, sharpening, noise adding, and JPEG compression etc., but also robust against the general geometric attacks such as rotation, translation, scaling, row or column removal, shearing, local geometric distortion and combination attacks etc.     

Updating the 2001 National Land Cover Database land cover classification to 2006 by using Landsat imagery change detection methods

The recent release of the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001, which represents the nation's land cover status based on a nominal date of 2001, is widely used as a baseline for national land cover conditions. To enable the updating of this land cover information in a consistent and continuous manner, a prototype method was developed to update land cover by an individual Landsat path and row. This method updates NLCD 2001 to a nominal date of 2006 by using both Landsat imagery and data from NLCD 2001 as the baseline. Pairs of Landsat scenes in the same season in 2001 and 2006 were acquired according to satellite paths and rows and normalized to allow calculation of change vectors between the two dates. Conservative thresholds based on Anderson Level I land cover classes were used to segregate the change vectors and determine areas of change and no-change. Once change areas had been identified, land cover classifications at the full NLCD resolution for 2006 areas of change were completed by sampling from NLCD 2001 in unchanged areas. Methods were developed and tested across five Landsat path/row study sites that contain several metropolitan areas including Seattle, Washington; San Diego, California; Sioux Falls, South Dakota; Jackson, Mississippi; and Manchester, New Hampshire. Results from the five study areas show that the vast majority of land cover change was captured and updated with overall land cover classification accuracies of 78.32%, 87.5%, 88.57%, 78.36%, and 83.33% for these areas. The method optimizes mapping efficiency and has the potential to provide users a flexible method to generate updated land cover at national and regional scales by using NLCD 2001 as the baseline.     

沙漠地区一种有效的地震勘探野外施工方法──等高面积组合法

本文通过对地震勘探检波组合物征函数的讨论，图解了检波组合时组内两相领检波器接收有效波的时差△ｔ对检波组合效应的影响，从而得出了△ｔ越大，组合的效果也越差的结论。