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A novel successive learning algorithm based on a Test Feature Classifier is proposed for efficient handling of sequentially provided training data. The fundamental characteristics of the successive learning are considered. In the learning, after recognition of a set of unknown data by a classifier, they are fed into the classifier in order to obtain a modified performance. An efficient algorithm is proposed for the incremental definition of prime tests which are irreducible combinations of features and capable of classifying training patterns into correct classes. Four strategies for addition of training patterns are investigated with respect to their precision and performance using real pattern data. A real-world problem of classification of defects on wafer images has been dealt with by the proposed classifier, obtaining excellent performance even through efficient addition strategies. 相似文献
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模拟我国南方沿海浪溅区和水位变动区的海工钢筋混凝土结构物的腐蚀环境,对掺入粉煤灰和矿渣的混凝土抗氯离子侵蚀性进行了试验。结果表明,在水灰比相同的条件下,加掺和料的混凝土抗氯离子侵蚀性高于普通混凝土。 相似文献
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Masahiro Tajima Miki Niwa Yasushi Fujii Yutaka Koinuma Reiji Aizawa Satoshi Kushiyama Satoru Kobayashi Koichi Mizuno Hideo Ohuˆchi 《Applied catalysis. B, Environmental》1997,12(4):1418
The decomposition of chlorofluorocarbons (CFCs) in the presence of water was examined over a variety of solid acid catalysts. The TiO2ZrO2 catalyst was found to have the highest activity and longest life among the catalysts examined. The activity of the TiO2ZrO2 catalysts depended upon the content of TiO2. At the contents of TiO2 from 58 to 90 mole%, the TiO2ZrO2 catalysts exhibited high activity, and these catalysts were proven to contain TiZrO4 crystal. From the study of the XRD peak intensity of the TiZrO4 crystal, it was highest on the TZ-58 which contained 58 mole% of TiO2, and decreased with increasing the content of TiO2. Furthermore, the conversion of CFC113 measured at 673 K was highest at TZ-58, and decreased gradually with increasing TiO2 content. Therefore, the TiZrO4 crystal influences the activity of decomposition of CFC113. However, the TiO2ZrO2 catalyst was gradually deactivated during the reaction due to the elimination of titanium atoms. A good relationship was found between the activity on TiO2ZrO2 catalyst and bond energy of CCl in the compounds of chlorofluorocarbons and hydrochlorocarbons, suggesting that the rate controlling step was the cleavage of CCl bond. 相似文献
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A real time control strategy for fuel cell hybrid vehicles is proposed. The objective is to reduce the hydrogen consumption by using an efficient power sharing strategy between the fuel cell system (FCS) and the energy buffer (EB). The energy buffer (battery or supercapacitor) is charge-sustained (no plug-in capabilities). The real time control strategy is derived from a non-causal optimization algorithm based on optimal control theory. The strategy is validated experimentally with a hardware-in-the-loop (HiL) test bench based on a 600 W fuel cell system. 相似文献
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距离曲面是一种常用的隐式曲面,它在几何造型和计算机动画中具有重要的应用价值,但以往往在对距离曲面进行多边形化时速较慢,为了提高点到曲线最近距离计算的效率,提出了一种基于最佳圆弧样条逼近的快速线骨架距离曲面计算方法,该算法对于一条任意的二维NURBS曲线,在用户给定的误差范围内,先用最少量的圆弧样条来逼近给定的曲线,从而把点到NURBS曲线最近距离的计算问题转化为点到圆弧样条最近距离的计算问题,由于在对曲面进行多边形化时,需要大量的点到曲线最近距离的计算,而该处可以将点到圆弧样条最近距离很少的计算量来解析求得,故该算法效率很高,该实验表明,算法简单实用,具有很大的应用价值。 相似文献
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针对研究院所研制的产品具有多传感器和数据传输速度快等特点,提出一种基于面向仪器系统的外设部件互连标准扩展总线平台的实时高速数据采集系统的设计方法,用于实现对产品性能的检测.该系统通过现场可编程门阵列将多通道传感器信号调理成为单通道低电压差分信号供图像采集卡进行采集,在上位机中采用LabVIEW的编程环境中构建的测试软件对采集得到的图像信号进行解析和存储,并将解析的结果按照一定的显示形式在虚拟仪器的面板上显示.测试软件可以通过对解析结果分析被测产品是否出现故障,并对故障信息进行记录和定位,操作员可以通过回放存储的数据对出现故障进行深入分析其原因.实验结果表明,在对100帧/秒、每帧图像为128×128×16位的实验环境中,在LabVIEW强大的自动多线程的编译环境下,只需要很低CPU的使用率和内存占用率就可以保证系统的图像采集、分析、存储和显示等多个线程准确有序的并行运行.测试系统有效地实现了高速图像信号的实时采集和分析,并且为传输速度更快的图像采集系统提供了一种可能性. 相似文献
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The change law of oxygen activity was studied by using Fe2O3‐CaO‐CaF2 and Na2CO3/Na2SO4 fluxes under laboratory conditions. At the same time, the range of oxygen activity which is in favour of removing phosphorus and sulphur simultaneously was also investigated. The results showed that the oxygen activity in the iron melt during de‐phosphorization can reach up to 5.91×10?6~10.03×10?6 in about 5 min and then only varies within a narrow range. A final phosphorus content of 0.008% and a final sulphur content of 0.003% can be obtained if the oxygen activity is controlled within the range of 4.5×10?6~8.0×10?6. 相似文献
10.
高级加密标准(Rijndael算法)介绍与探讨 总被引:4,自引:0,他引:4
在介绍新型高级加密标准(advance encryption standard,AES)——Rijndael算法的基础上,重点介绍了算法的实现及相应的解密过程;并结合算法的实现与解密过程对该算法的优点和应用前景作了简要分析。 相似文献