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161.
提出了基于形态学微分的车牌字符分割算法。首先运用形态学微分算法获取车的边界,然后通过巧妙选择连通区域进行深度搜索即可直接获得车牌每个字符的矩形区域。本方法省去了一般车牌识别中的车牌定位部分,对有一定倾角的车牌也有一定的适应能力。 相似文献
162.
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164.
根据部分K值逻辑的完备性理论以及准完备集之间的相似关系理论,定出了部分四值逻辑的所有准完备集的最小覆盖,从而解决了部分四值逻辑中Sheffer函数的判定问题。 相似文献
165.
Summary A new method for transforming grammars into equivalent LL(k) grammars is studied. The applicability of the transformation is characterized by defining a subclass of LR(k) grammars, called predictive LR(k) grammars, with the property that a grammar is predictive LR(k) if and only if the corresponding transformed grammar is LL(k). Furthermore, it is shown that deterministic bottom-up parsing of a predictive LR(k) grammar can be done by the LL(k) parser of the transformed grammar. This parsing method is possible since the transformed grammar always left-to-right covers the original grammar. The class of predictive LR(k) grammars strictly includes the class of LC(k) grammars (the grammars that can be parsed deterministically in the left-corner manner). Thus our transformation is more powerful than the one previously available, which transforms LC(k) grammars into LL(k) form. 相似文献
166.
NOTE The Application of Surface Analysis Techniques in the Adhesive Bonding of Oily Automotive Steel
There are fewer papers on the adhesive bonding of steel for structural applications than for aluminum and titanium alloys. However, the approach to the adhesive bonding of all three adherends has been similar, that is, the surfaces are pretreated prior to bonding. Trawinski, et al.1,2,3 reviewed several conversion coatings or etching processes used for steel. Haak and Smith4 selected two surface treatments among nineteen based on minimal cost, simplicity and good durability. Smith5 has reported work on stainless steel-epoxy bonds under hydrothermal stress. Bischof, et al.6 investigated the effect of surface pretreatment of steel on bonding strength obtained with polyvinyl chloride. Ziane, et al.7 identified four fracture zones resulting from shear loading of epoxy bonded galvanized steel following four different surface pretreatments. But in some cases, as in the automotive industry, there is a need to bond oily steel directly without surface pretreatment. Rosty, et al.8 have reported a study of the role of fillers and cure temperature on the shear strength of oily steel bonded with epoxy. None of the reported research utilizes both microscopic and spectroscopic techniques to analyze the fracture surfaces. 相似文献
167.
孙荣荣 《平顶山工学院学报》2006,15(4):6-7
在分析了龄期对碳化深度、回弹值以及混凝土强度影响的基础上进一步分析了龄期对回弹测强曲线使用的影响。 相似文献
168.
Kenneth T. Leong James C. Booth J. H. Claassen 《Journal of Superconductivity and Novel Magnetism》2006,19(7-8):637-648
We introduce a novel transmission-line method for determining the penetration depth in thin high-temperature superconducting
(HTS) films. The method is based on the accurate measurement of the inductance per unit length of a superconducting coplanar-waveguide
(CPW) transmission line fabricated on the HTS sample. Using the experimentally obtained inductance per unit length, we interpolate
the penetration depth from a table of numerically determined values of inductance (per unit length) as a function of penetration
depth, calculated from a coupled transmission-line model. A novelty of our procedure is the utilization of the multiline thru-reflect-line
(TRL) method and the calibration-comparison method to accurately determine the inductance per unit length of the superconducting
transmission line. By measuring different CPW geometries patterned onto the same thin-film sample, we can verify our penetration
depth values. We demonstrate this technique by extracting the penetration depth for several different HTS films at 76 K. Estimated
uncertainties in the extracted penetration depth are also provided.
Contribution of an agency of the US government not subject to copyright. 相似文献
169.
Porous titanium dioxide (Titania) thin films were grown by anodic oxidation using high purity (99.7%) titanium foil in a dilute sulphuric acid (1 M) medium. The anodization process was carried out for 30 minutes with 20 mA/cm2 and 50 mA/cm2 current densities. The samples were characterized by XRD, SEM, and AFM techniques. It was found that the grown porous titania films were less sensitive to 500 ppm hydrogen in air ambient below 300°C; however, the sensitivity and response behavior of the film at 300°C are very much dependent on the growth conditions. Particularly, the films grown at current density 50 mA/cm2 and 1 M acid concentration exhibited the lowest response time of 151 sec at 300°C. 相似文献
170.
目的应用高压水射流进行混凝土构件表面处理前确定机械的初始参数。实现对处理深度全面合理的控制.方法用AJP-E25135型高压泵,RG-2002HNDF型、口径为0.25mm七喷嘴旋转喷枪,对36组不同的初始参数、同批制作的砾石混凝土试块进行了高压水射流表面处理试验,并运用人工神经网络技术,对试验数据进行理论分析.结果建立了压力、靶距、口径、S/A(砂率)与处理深度关系的预测模型并把模型的预测结果与实验结果进行了比较,平均相对误差为0.0005.结论模型能够满足工程实际需要.可用于混凝土构件表面处理深度的估计与分析,以及特定处理深度条件下初始参数的预测.并可广泛应用于高压水表面处理深度模型的参数优化选择。智能化控制等领域. 相似文献