互联网上几个免费专利资源及其检索利用

在科研活动中，专利文献作为重要的信息资源，其检索功能起到了重要的作用。介绍了专利文献的作用和互联网上几个常用的免费专利数据库资源，并对这些专利资源的基本检索方法作了介绍。对专利资源检索的一般技巧进行了一定的总结，为人们进行专利文献的检索提供一些简便易行的方法和经验。     

一种基于主色调匹配的图像检索方法

在基于内容的图像检索中，颜色作为图像的一种重要视觉信息已得到广泛的应用，主色调可以反映一幅图像的基本面貌，其实质就是用较少的颜色来表示原图像，并且在视觉上与原图像相似，由此，在均匀颜色空间中利用聚类分析的方法将色彩聚类为几种主要颜色，从而实现对颜色的量化，并利用直方图表示主色信息，最后采用直方图交叉算法进行图像的相似度匹配，取得了满意的实验效果。     

面向领域的软件构件库系统初步研究

本文主要分析了面向领域应用的软件构件库系统总体框架，包括软件构件概念、软件构件库的总体结构及其相关内容。     

利用分形编码进行基于形状的图像检索

分形编码在图像压缩方面取得了很好的效果,同时也能够用于基于内容的图像检索。该文结合分形技术,提出了一种有效的抽取特征检索图像的新方法。针对目前基于形状的图像检索领域中存在的问题,首先提出了一种通过构造不规则区域的相似膨胀分形编码算法,该算法能获得较高的压缩比。在图像检索中,该算法用一新的方式提取形状特征,实现了基于该算法的图像检索操作。实验结果表明该文算法能较好地描述图像的形状及空间分布信息,明显地提高了检索效率及准确度。     

一种基于颜色块直方图的图像检索方法

提出了一种基于颜色直方图与颜色块相结合的图像检索的新方法。定义了一种新的四维图像特征矢量，它是由颜色直方图，同一种颜色的颜色块个数，同一种颜色块之间的平均距离和同一种颜色块内的平均距离组成。颜色直方图用来获取图像颜色分布的全局信息，利用后三个特征值来获取图像颜色的空间分布信息。通过对图像数据库的检索表明该算法明显优于直方图法。     

Modeling the impact of spectral sensor configurations on the FLD retrieval accuracy of sun-induced chlorophyll fluorescence

Chlorophyll fluorescence is related to photosynthesis and can serve as a remote sensing proxy for estimating photosynthetic energy conversion and carbon uptake. Recent advances in sensor technology allow remote measurements of the sun-induced chlorophyll fluorescence signal (Fs) at leaf and canopy scale. The commonly used Fraunhofer Line Depth (FLD) principle exploits spectrally narrow atmospheric oxygen absorption bands and relates Fs to the difference of the absorption feature depth of a fluorescensing and a non-fluorescensing surface. However, due to the nature of these narrow bands, Fs retrieval results depend not only on vegetation species type or environmental conditions, but also on instrument technology and processing algorithms. Thus, an evaluation of all influencing factors and their separate quantification is required to further improve Fs retrieval and to allow a reproducible interpretation of Fs signals.Here we present a modeling study that isolates and quantifies the impacts of sensor characteristics, such as spectral sampling interval (SSI), spectral resolution (SR), signal to noise ratio (SNR), and spectral shift (SS) on the accuracy of Fs measurements in the oxygen A band centered at 760 nm (O₂-A). Modeled high resolution radiance spectra associated with known Fs were spectrally resampled, taking into consideration the various sensor properties. Fs was retrieved using the three most common FLD retrieval methods, namely the original FLD method (sFLD), the modified FLD (3FLD) and the improved FLD (iFLD). The analysis investigates parameter ranges, which are representative for field and airborne instruments currently used in Fs research (e.g., ASD FieldSpec, OceanOptics HR, AirFLEX, AISA, APEX, CASI, and MERIS).Our results show that the most important parameter affecting the retrieval accuracy is SNR, SR accounts for ≤ 40% of the error, the SSI for ≤ 12%, and SS for ≤ 7% of the error. A trade-off study revealed that high SR can partly compensate for low SNR. There is a strong interrelation between all parameters and the impact of specific parameters can compensate or amplify the influence of others. Hence, the combination of all parameters must be considered by the evaluation of sensors and their potential for Fs retrieval. In general, the standard FLD method strongly overestimates Fs, while 3FLD and iFLD provide a more accurate estimation of Fs. We conclude that technical sensor specifications and the retrieval methods cause a significant variability in retrieved Fs signals. Results are intended to be one relevant component of the total uncertainty budget of Fs retrieval and have to be considered in the interpretation of retrieved Fs signals.     

基于数据库的字符串检索

讨论了在VFP6.0数据库软件开发中,在信息查询时,给出了字符串可按任意关键字检索的一种有效方法.     

Multimedia technologies for structuring and retrieval of TV news

Because of the media digitization, a large amount of information such as speech, audio and video data is produced everyday. In order to retrieve data from these databases quickly and precisely, multimedia technologies for structuring and retrieving of speech, audio and video data are strongly required. In this paper, we overview the multimedia technologies such as structuring and retrieval of speech, audio and video data, speaker indexing, audio summarization and cross media retrieval existing today for TV news detabase. The main purpose of structuring is to produce tables of contents and indices from audio and video data automatically. In order to make these technologies feasible, first, processing units such as words on audio data and shots on video data are extracted. On a second step, they are meaningfully integrated into topics. Furthermore, the units extracted from different types of media are integrated for higher functions. Yasuo Ariki, Ph.D.: He is a Professor in the Department of Electronics and Informatics at the Ryukoku University. He received his B.E., M.E. and Ph.D. in information science from Kyoto University in 1974, 1976 and 1979, respectively. He had been an Assistant in Kyoto University from 1980 to 1990, and stayed at Edinburgh University as visiting academic from 1987 to 1990. His research interests are in speech and image recognition and in information retrieval and database. He is a member of IPSJ, IEICE, ASJ, Soc. Artif. Intel. and IEEE.     

快速JPEG图像检索方法

本文给出了一种基于归一化化转动惯量(NormalizedMomentInertia,NMI)的JPEG图像快速检索方法,其特点是直接在压缩域中利用DCT系数进行块分类,每一类分块形成一个二值索引图,统计该索引图的NMI值作为该类的一个特征,所有类的NMI特征构成了图像的一个特征序列,以此进行图像检索。本方法不需要完全解压缩,降低了计算复杂度,对图像的平移,旋转和尺度变换有较好的鲁棒性。试验结果表明这种图像检索方法具有良好的检索性能。     

颜色的空间分布密度与图像检索

提出了颜色的空间分布密度的概念,给出了颜色的空间分布密度的算法,证明了算法的合理性和有效性.在基于内容的图像检索中,颜色的空间分布密度能提供颜色在空间的分布信息.实验表明,颜色的空间分布密度与颜色直方图配合使用,可以提高图像检索的准确率与回召率.