基于IDMEF的大规模协同IDS架构

为了实现IDS系统的分布化、协同化和标准化,入侵检测消息交换格式(IDMEF)相关标准已被广泛地应用到IDS领域中。该文讨论了一种基于IDMEF标准的大规模协同IDS构架,对基于Prelude框架和开发包的IDS协同系统进行了分析、设计和实现,并研究了该架构在CERNET网络中的部署和应用方法。经初步应用证明,该系统可以基本满足需求,达到了IDS的分布化、协同化和标准化的要求。     

步进频连续波体制生命迹象探测方法研究

基于步进频连续波,利用MTD滤波,通过时域、频域联合检测,研究了生命迹象探测的新方法,在检测到人体的同时,实现测距的目的。首先,基于人体微动模型建立步进频连续波生命迹象探测的回波模型;然后由回波得到距离像信息,划分距离门,经时域检测后,对有信号的距离门内距离峰值变化信息进行傅里叶变换;再通过MTD滤波,滤除静止目标的影响,经频域检测,即可检测到人体。仿真证明了该方法的有效性。     

利用数字图像处理技术测量零件几何尺寸

基于图像处理技术的零件尺寸自动检测方法可避免传统人工检测方法的各种弊端。本文探讨了图像处理的基本流程、图像处理方法和分析计算,并通过实例证明了该检测方法的可行性。     

Turbo CDMA多用户检测的研究

简述了Turbo译码原理及逐符号最大后验算法,并将Turbo译码原理应用于CDMA系统的多用户检测;提出了基于Turbo译码原理的多用户检测接收机方案,通过计算机仿真验证了该方案的性能。结果表明,该方案经过4次迭代之后,其误码率接近单用户界,这种接收机可去除多址干扰（MAI）的影响。     

计算机数字图像处理技术在刑侦工作中的应用

论述了计算机数字图像处理技术与传统摄影技术相比在技术上的先进性 ,展望了计算机数字图像处理技术在刑侦中的具体应用领域 ,讨论了发展计算机数字图像处理技术应注意的问题 ,阐述了计算机数字图像处理技术必将极大促进刑侦工作的观点     

Jump-detection and curve estimation methods for discontinuous regression functions based on the piecewise B-spline function

Jump-detection and curve estimation methods for the discontinuous regression function are proposed in this article. First, two estimators of the regression function based on B-splines are considered. The first estimator is obtained when the knot sequence is quasi-uniform; by adding a knot with multiplicity p + 1 at a fixed point x₀ on support [a, b], we can obtain the second estimator. Then, the jump locations are detected by the performance of the difference of the residual sum of squares DRSS(x₀) (x₀ ∈ (a, b)); subsequently the regression function with jumps can be fitted based on piecewise B-spline function. Asymptotic properties are established under some mild conditions. Several numerical examples using both simulated and real data are presented to evaluate the performance of the proposed method.     

从《牙医谋杀案》看阿加莎·克里斯蒂侦探小说的特殊魅力

本文以《牙医谋杀案》为例,从破案模式、人物形象塑造和案件设计三个角度出发,探讨了阿加莎·克里斯蒂侦探小说的特殊魅力所在。     

铰接平面多杆机构杆件布层的一种自动化算法

本文针对铰接平面多杆机同构同一运动平面层上杆件干涉的原因，提出一种建立在杆件平面几何形状基础之上的自动化在布层算法。该算法通过检查显示构件外轮廓线上象素的方法，来发现是否干涉，从而确定构件所在的运动平面层。     

Improvements over the duplicate performance method for outlier detection in categorical multivariate surveys

Summary The detection of errors and outliers is an important step in data processing, especially those errors arising from data entry operations because they are of the entire responsability of the data processing staff. The duplicate performance method, is commonly used as an attempt to detect such type of errors. It implies typically typing twice the same data without any special precedence. If the errors are uniformly distributed among individuals, retyping a fraction of the total will also remove typically the same fraction of the errors. A new method is presented, which is able to improve that procedure by sorting the records putting first the most unlikely ones. The ability of the present methodology has been tested by a Monte Carlo simulation, using an existing database of categorical answers of housing characteristics in Uruguay. At first, it has been randomly contaiminated, and after that, the proposed procedure applied. The results show that if a partial retyping is done following the proposed order about 50 % of the errors can be removed while keeping the retyping effort between 4 and 14% of the dataset, while to attain a similar result with the standard methodology 50% (on, average) of the database should be processed. The new ordering is based upon the unrotated Principal Component Analysis (PCA) transformation of the previously coded data. No special shape of the multivariate distribution function is assumed or required.     

激光扫描声学显微镜图像信号的分析与处理

提出了激光扫描声学显微镜（ＳＬＡＭ）图像信号的近似模型，针对ＳＬＡＭ图像的统计特性和各个环节噪声特性，提出了密度比较算法，采用数学形态滤波，对图像进行了处理，并给出实验结果。