Three dimensional particles identification and shape parameters research on coarse aggregates of asphalt mixture using X-ray CT images

In this paper a series of digital image processing methods were adopted for getting separated coarse aggregates from asphalt mixture specimen using high-resolution X-ray Computed Tomography (CT) images.The existing three dimensional (3D) particles matching methods based on two dimensional (2D) continuous cross-sections were analyzed and a new ’overlap area method’ was presented.After the 3D particles were extracted one by one successfully,the basic parameters of each aggregate:perimeter,area,surface area,and volume were calculated by chain code method.Finally,the 3D mass center coordinates and the sphericity index were introduced.     

基于Hash函数的RFID安全认证协议研究

RFID得到了越来越广泛的关注和应用,但是其存在安全和隐私保护的问题值得重视和关注.在现有RFID安全认证协议的基础上,分析了3种典型的Hash函数认证协议的缺陷,提出了一种基于Hash函数的双向认证协议,较好地解决了RFID的安全隐患和高效低成本问题.该协议具有抗重放、抗分析、防伪造、防跟踪等特性,并且适用于大规模的...     

基于CT图像的粗集料颗粒接触特性细观尺度研究

采用工业CT获取沥青混合料断面扫描图像,利用数字图像处理方法将粗集料从图像中分离,并解决了颗粒粘连问题,使粗集料颗粒成为单独个体.确立了粗集料颗粒之间接触的判定准则,并设计5像素×5像素大小的窗格沿颗粒边缘进行接触搜索.对640张断面图像遍历处理后获得的数据进行定性分析,尝试建立了接触度指标C.采用4种概率密度分布函数...     

基于Web服务的煤炭销售票管理系统的设计与实现

煤炭销售票系统解决了销售票手工管理中存在的众多问题,同时系统的建设和应用使得煤炭销售票管理水平发生质的变化和全省煤炭运销监控水平历史性地提升.利用Web服务的体系结构和它的关键技术,设计了基于Web服务的煤炭销售票系统,维护煤炭生产、销售和运输的健康发展.