基于运动矢量的视频图象数字水印算法

数字水印技术是近年发展起来的一种用于数字产品版权保护和真伪性论证的新兴技术。与静止图象相比，视频水印技术要满足盲检的要求。本文根据运动矢量的特征值ρl，提出了一种视频图象水印新算法。实验结果表明，所提出的水印算法简单、快速，能满足视频编码的实时性要求；算法与现有的视频压缩标准有很好的兼容性；水印的提取具有盲检功能，无需原图象；水印的嵌入不影响I帧的图象质量，与嵌入水印前的原压缩图象相比，嵌入水印后的视频图象信噪比损失很小。     

标准化钻速法检测地层压力技术的改进与应用

利用钻井资料检测地层压力的方法，基本上都是以泥岩的压实规律为基础，以钻速的变化为根据的。但是在钻井过程中影响钻速的因素很多，可以衡量一种检测方法优劣，主要是看其能否合理、全面地考虑诸多影响因素，能否适用于现场。本文介绍标准化钻速法检测地层压力的基本原理和工作步骤，提出了适用于现场的改进的数学模型和应用方法，并与实测值很接近。     

利用梯度方向信息的随机Hough变换

针对随机Ｈｏｕｇｈ变换（ＲＨＴ）在处理复杂图像随机采样造成的大量无效积累提出一种改进的用于直线检测的ＲＨＴ，较发地解决了无效果累积问题，并使改进后的算法具有计算速度更快，占用内存更少以及检测性能更好等优点。     

基于空间矩的灰度边缘亚像元度量精度分析

灰度图像中边缘定位受采样密度限制，亚像元精度度量方法在需要高精度的应用中受到重视，要想知识到底需要多高的分辨率才能达到定精度指标，就有必要分析特征定位方法的最坏情况的精度，文中用分析和实验的方法给出了基于空间矩的边缘定位方法，对于边缘点，边缘直线以及直边缘区域的最坏情况定位精度分析。分析和讨论的结果不但可以用来确定已知形状位置估计的最大误差，而且还可用于对准的形状几何参数，以获得较高的精度。     

An improved method for magnetic identification and localization of cracks in conductors

A SQUID magnetometer can be used to measure the magnetic field produced by flaws in a two-dimensional, conducting plate carrying a current. Identification of the flaw-induced magnetic field is difficult because of the large magnetic field associated with the edges of the plate and the current in the leads that connect the plate to the power supply. We have developed a technique by which the wire and edge fields can be cancelled prior to mapping the magnetic field. In this technique, a similar unflawed conducting sheet is placed adjacent to the flawed plate, with a connection between the sheet and the plate at one edge, and with the opposite edges of the sheet and of the plate connected to the two conductors of a coaxial cable. Thus, an applied current will flow along one conductor of the cable, across the cancelling sheet, cross into the flawed plate, return along the plate, and then return to the power supply along the other conductor of the coaxial cable. As a result of this geometry, there is no magnetic field from the lead-in wires because they are coaxial, and the magnetic field due to the edges of the plate is cancelled by the opposing magnetic field of the edges in the adjacent sheet. The extent of cancellation is determined primarily by the separation between the plate and the cancelling sheet, by the thickness of the plate, and by macroscopic inhomogeneities in their electrical conductivities.     

高功率激光焊接光致等离子体的检测

系统地归纳了高功率激光焊接过程中光致等离子体的声、光、电、热等四种特征信号，综述了国外在等离子体信号检测方面的试验方法及研究进展，分析了未来的发展趋势     

一种基于Hough变换的声呐对目标航迹检测算法研究

为提高声呐对目标航迹的检测性能,从单部声呐时间融合的角度出发,提出了一种基于Hough变换的声呐信号检测算法。该算法把航迹上的观测点变换为参数空间的对应曲线,充分利用一段时间内的目标观测数据,在低信噪比下也能从背景噪声中提取目标的航迹特征,提高了声呐的检测概率,且对部分信息和数据的缺失不敏感。仿真试验证明了该算法的有效性。     

双辊薄带钢连铸在线自动检测系统

介绍了双辊薄带钢连铸工艺,设计了双辊连铸机的计算机在线自动检测系统,通过采取正确的抗干扰措施提高了检测的精度,系统在双辊薄带钢连铸试验中应用效果良好.     

入侵检测系统技术现状及其发展趋势

阐述了入侵检测系统（IDS）的起源、发展和分类，介绍了它的结构和标准化工作，对入侵检测系统存在的问题及发展趋势作了概述。     

The temperature dependence of luminescence from a long-lasting phosphor exposed to ionizing radiation

The temperature dependence of luminescence from a long-lasting phosphor (LLP), SrAl₂O₄ : Eu²⁺,Dy³⁺, exposed to ionizing radiation has been measured to understand the LLP luminescence mechanism. Evaluation of the decay constants of the LLP exposed to -, β- or γ-rays at temperatures from 200 to 390 K showed that the decay constant is divided into four components ranging from 10⁻⁴ to 10⁻¹ s⁻¹ with activation energies of 0.02–0.35 eV.

Total luminous intensity from the LLP with changing irradiation temperature has its maximum value around the room temperature. Irradiation at elevated temperature (390 K) has the total luminescence pattern with monotonous decrease as temperature rises. As a result of evaluating the temperature dependence of luminescence, the luminescence mechanism is considered as follows:

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