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101.
The technical characters of mobile agent (MA) originated in the distributional artificial intelligence domain is introduced. A network management construction based on agent (NMCA) is then proposed. The NMCA structure features are elaborated in detail. A prototype design of NMCA is given by using the jKQML programming. The establishment of NMCA platform will be helpful to reduce the correspondence load of network management and improves the efficiency and the expansion ability of network management systems.  相似文献   
102.
Recently Fourier Transform Infrared (FTIR) spectroscopic imaging has been used as a tool to detect the changes in cellular composition that may reflect the onset of a disease. This approach has been investigated as a mean of monitoring the change of the biochemical composition of cells and providing a diagnostic tool for various human cancers and other diseases. The discrimination between different types of tissue based upon spectroscopic data is often achieved using various multivariate clustering techniques. However, the number of clusters is a common unknown feature for the clustering methods, such as hierarchical cluster analysis, k-means and fuzzy c-means. In this study, we apply a FCM based clustering algorithm to obtain the best number of clusters as given by the minimum validity index value. This often results in an excessive number of clusters being created due to the complexity of this biochemical system. A novel method to automatically merge clusters was developed to try to address this problem. Three lymph node tissue sections were examined to evaluate our new method. These results showed that this approach can merge the clusters which have similar biochemistry. Consequently, the overall algorithm automatically identifies clusters that accurately match the main tissue types that are independently determined by the clinician.  相似文献   
103.
组织协同进化分类算法用于雷达目标一维像识别   总被引:4,自引:3,他引:1       下载免费PDF全文
针对雷达目标一维像识别问题,提出了一种基于组织协同进化分类算法的识别方法.该方法与现有进化分类方法的不同之处在于它的进化操作直接作用于样本而不是规则,采用了一种自下而上的搜索机制,即先使若干样本的集合得到进化,再从进化结果中提取规则.这样有利于避免在进化过程中产生无意义的规则.该方法不需要进行特征提取;对于高维数据,不需要预先进行降维处理;没有复杂的运算,训练和识别的速度都很快.对3种飞机微波暗室实测数据的识别实验表明,该方法性能稳定,优于基于支撑矢量机与子波核函数的方法,识别率均达到了96%以上.实验中还对算法的抗噪能力进行了测试,获得了良好的效果.  相似文献   
104.
This study examined how 1 symbol is selected to control the allocation of attention when several symbols appear in the visual field. In Experiments 1-3, the critical target feature was color, and it was found that uninformative central arrows that matched the color of the target were selected and produced unintentional shifts of attention (i.e., involuntary, initiated slowly, producing long-lasting facilitatory effects). Experiment 4 tested whether such selection is the result of an attentional filter or of a competition bias due to a match of incoming information against integrated object representations stored in working memory. Here, the critical feature was shape and color was irrelevant, but matching color arrows were still selected. Thus, features of objects in working memory will bias the selection of symbols in the visual field, and such selected symbols are capable of producing unintentional shifts of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
With increasing globalization, communication across language and cultural boundaries is becoming an essential requirement of doing business, delivering education, and providing public services. Due to the considerable cost of human translation services, only a small fraction of text documents and an even smaller percentage of spoken encounters, such as international meetings and conferences, are translated, with most resorting to the use of a common language (e.g. English) or not taking place at all. Technology may provide a potentially revolutionary way out if real-time, domain-independent, simultaneous speech translation can be realized. In this paper, we present a simultaneous speech translation system based on statistical recognition and translation technology. We discuss the technology, various system improvements and propose mechanisms for user-friendly delivery of the result. Over extensive component and end-to-end system evaluations and comparisons with human translation performance, we conclude that machines can already deliver comprehensible simultaneous translation output. Moreover, while machine performance is affected by recognition errors (and thus can be improved), human performance is limited by the cognitive challenge of performing the task in real time.  相似文献   
106.
道路与匝道中线自动绘制的算法与实现   总被引:1,自引:0,他引:1  
道路与立交匝道平面中线的计算机自动绘制是道路路线CAD软件的核心功能之一,在道路工程计算机动态交互式设计、计算机辅助成图方面具有基础性作用.依据道路中线线形的曲率变化特点,推导了道路中线坐标计算的通用数学模型,并根据一个工程实例在通用图形系统AutoCAD环境下实现了道路与匝道中线的自动绘制.  相似文献   
107.
108.
The main prerequisites are considered in a historical aspect and steps ate taken in creating a world-wide metrology system with the aim of providing conditions for the mutual recognition of measurement results. __________ Translated from Izmeritel’naya Tekhnika, No. 11. pp. 59–62, November, 2007.  相似文献   
109.
The time course of spoken word recognition depends largely on the frequencies of a word and its competitors, or neighbors (similar-sounding words). However, variability in natural lexicons makes systematic analysis of frequency and neighbor similarity difficult. Artificial lexicons were used to achieve precise control over word frequency and phonological similarity. Eye tracking provided time course measures of lexical activation and competition (during spoken instructions to perform visually guided tasks) both during and after word learning, as a function of word frequency, neighbor type, and neighbor frequency. Apparent shifts from holistic to incremental competitor effects were observed in adults and neural network simulations, suggesting such shifts reflect general properties of learning rather than changes in the nature of lexical representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
张鸿宾 《自动化学报》1991,17(4):439-446
本文提出一种基于轮廓线匹配的二维重迭物体的识别算法,并采用一种点模式匹配的快 速算法进行特征点序列的匹配,通过引进形状移位数的概念和利用问题中的各种约束条件,提 高了物体识别速度.  相似文献   
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