一种机场跑道异物检测中毫米波雷达工作信号格式的设计

文章通过一系列的理论运算与分析,对设置于机场跑道两端的毫米波雷达的工作信号功率、格式及极化方式进行了设计。给出了机场跑道FOD检测中架设于跑道两端的毫米波雷达的发射波格式,并提出了有很好抗干扰能力的变极化工作方式,这不仅提高了检测精度,而且对于FOD分类起到了积极作用,在某种程度上可以替代高分辨率视频设备,对机场FOD检测的设备优化起到了积极作用。     

基于语料库的数据驱动模式下的大学英语写作研究

随着语料库在英语教学领域的应用和普及,数据驱动学习作为一种新的基于语料库的学习方法也逐渐受到研究者的关注。本文从英语写作教学入手,概括了数据驱动学习方法的主要特点,重点探讨了如何把语料库应用于英语写作教学。     

论全球化背景下现代地域建筑的发展

通过对传统地域建筑主要成因与现代地域性建筑实践的分析,从深层次上认识建筑的本质内涵与发展演变规律,进一步探讨全球化背景下地域建筑体系的如何更新与重构．     

基于Petri网的面向动态演化的软件体系结构建模

为了应对软件动态演化面临的挑战,应提高所建立的软件体系结构模型的动态演化性.以扩展的Petri网为形式化工具,对面向动态演化的软件体系结构进行建模.首先,将Petri网扩展成为构件网结构,并设计有效支持软件动态演化的构件模型和连接件模型;其次,建立软件体系结构的静态视图和动态视图,为软件动态演化的分析和实施奠定基础;最后,通过案例研究表明:该方法是有效的,并可显著提高所建立的软件体系结构模型的动态演化性.     

锂电池组能量均衡的模糊-PI控制研究

在串联锂电池组能量均衡控制算法的基础上,提出一种新的能实现锂电池组能量均衡的控制方案。介绍模糊-PI复合控制器,包括控制器输入输出、规则库和PI参数的设计,结合模糊控制不依赖数学模型及其快速响应性、PI控制无静差的优点,改进电池模糊控制均衡的效率和精度。实验结果表明,该方案能改善模糊控制在电池充放电能量均衡过程中控制精度较差的问题,实现较为高效的均衡。     

GIS在公共气象服务网站的应用

给出以GIS分析为核心的公共气象服务网站框架。阐述GIS与多时空尺度气象要素间的相互关系,GIS在系统逻辑分层中的位置,一维、二维、三维分析图的网页功能。同时对GIS应用中所面对的一些关键技术进行了深入分析。如含权地理边界预剪裁气象要素插值算法、netCDF文件产生、二维和三维可视化技术等等。该套系统已经在中国天气网、四川气象网、成都公共气象服务网等网站中得到应用。     

基于结构继承的贝叶斯网结构学习优化设计

采用遗传算法建立贝叶斯网络的优化学习结构,一直是贝叶斯网络研究倍受关注的课题.传统遗传算法的个体设计存在需要反复进行无环性检验的问题,降低了进化效率.针对这个问题,提出一种新的个体编码方式.考虑到进化过程中家族得分的可继承性,提出基于家族继承的结构评分改进算法,进而设计相应的改进遗传算法.实验结果表明,改进算法在BN建网精度与效率上都得到明显提升.     

Fuzzy Distance-Based Range Queries over Uncertain Moving Objects

Data obtained from real world are imprecise or uncertain due to the accuracy of positioning devices,updating protocols or characteristics of applications.On the other hand,users sometimes prefer to qualitatively express their requests with vague conditions and different parts of search region are in-equally important in some applications.We address the problem of efficiently processing the fuzzy range queries for uncertain moving objects whose whereabouts in time are not known exactly,for which the basic syntax is find objects always/sometimes near to the query issuer with the qualifying guarantees no less than a given threshold during a given temporal interval.We model the location uncertainty of moving objects on the utilization of probability density functions and describe the indeterminate boundary of query range with fuzzy set.We present the qualifying guarantee evaluation of objects,and propose pruning techniques based on the α-cut of fuzzy set to shrink the search space efficiently.We also design rules to reject non-qualifying objects and validate qualifying objects in order to avoid unnecessary costly numeric integrations in the refinement step.An extensive empirical study has been conducted to demonstrate the efficiency and effectiveness of algorithms under various experimental     

Vessel segmentation and width estimation in retinal images using multiscale production of matched filter responses

Automated segmentation of blood vessels in retinal images can help ophthalmologists screen larger populations for vessel abnormalities. However, automated vessel extraction is difficult due to the fact that the width of retinal vessels can vary from very large to very small, and that the local contrast of vessels is unstable. Further, the small vessels are overwhelmed by Gaussian-like noises. Therefore the accurate segmentation and width estimation of small vessels are very challenging. In this paper, we propose a simple and efficient multiscale vessel extraction scheme by multiplying the responses of matched filters at three scales. Since the vessel structures will have relatively strong responses to the matched filters at different scales but the background noises will not, scale production could further enhance vessels while suppressing noise. After appropriate selection of scale parameters and appropriate normalization of filter responses, the filter responses are then extracted and fused in the scale production domain. The experimental results demonstrate that the proposed method works well for accurately segmenting vessels with good width estimation.     

利用VB实现WinCC数据高级归档的研究和应用

随着信息化步伐的加快,企业对生产数据归档的要求越来越高,利用传统方式实现WinCC数据归档已不能满足生产需要。通过对现有WinCC软件的OPC接口分析,提出了采用开发效率高的VB软件和数据存储功能强大的SQL软件对WinCC进行二次开发的可行方案。该方案实现了对WinCC过程数据的高级归档,满足企业对数据归档的要求,同时避免了使用西门子专用归档选件带来的高成本开发。目前,该方案已在工程应用中取得了较好效果,具有一定的应用推广价值。