A new approach for deducing the stage-discharge relationship of a triangular broad-crested device

In this paper, the outflow process of a triangular broad-crested device is examined using the dimensional analysis and the incomplete self-similarity theory. A new theoretical stage-discharge relationship is proposed, and its applicability is verified using measurements available in literature.The proposed power equation is characterized by a coefficient depending on device apex angle and a constant value of the exponent.     

煤粉碎粒度分布的分形模型

从自相似分形几何原理出发,建立了煤粉碎粒度分布的分形模型,得到了煤粉碎的分形粒度分布公式。结果表明:煤粉碎的粒度分布维数取决于煤粒的粉碎概率和粉碎相似比,影响煤粉碎粒度分布的因素有煤粉碎的粒度分布维数和煤粉碎后煤粒的最大粒径,煤粉碎的粒度分布维数反映了煤粉碎后煤粉颗粒群粒级的粗细程度。通过分形粒度分布与实际粒度分布的比较,验证了本模型的正确性,可用于指导工程实际。     

根据声发射自相似性特征进行混凝土材料断裂的识别和预报

本文在试验基础上 ,通过分析给出了定量考察声发射过程自相似性的自相似特征函数。并在此基础上 ,根据混凝土试块的三点弯曲试验 ,确定出了混凝土试块断裂的声发射自相似性识别特征 ,根据这些特征 ,可以进行混凝土材料断裂的识别和预报     

片上网络业务量的自相似性分析及模型研究

进行片上网络的架构、映射、流控与服务质量(Quality of Service,QoS)等研究时,迫切需要一个准确的业务量模型用于延时分析与测试验证,以保证设计的性能。而现有的基于马尔科夫模型和回归模型的短程相关模型无法准确地描述业务量的突发性和分形特性,不适用于基于流水的通信信号处理片上系统(System on Chip,SoC)芯片。为了解决这个问题,通过理论与实验相结合的方法,研究了网络拓扑、任务流图、映射对业务量自相似性的影响,根据通信系统的信号处理特点建立了多处理器片上系统(Multi-core Processing System on Chip,MPSoC)数据关联模型,利用典型DSP系统进行建模实验,用实测的业务量Hurst参数拟合数据关联模型参数与Hurst参数的经验函数关系式,建立了用MPSoC数据关联模型预测和估计业务量Hurst参数的方法。实验表明,采用该业务量模型估计的Hurst参数与其真实值误差较小,能较准确地描述业务量的自相似性。     

一种新型的基于网络流量自相似性的DDoS入侵诊测方法

This paper presents a new method of DDoS Intrude Detection Based on Self-Similarity of Network Traffics based on analysis of parameter of self-similar, which includes Hurst parameter, Holder parameter (Time variable function H(t)), we do research on the affect of H parameter change brought by DDoS attack. And we discover the DDoS attack can be detected in some extent by measure the change of H parameter, as it showed by the research result this network traffic based method can detected DDoS attack and is more reliable on the recognition of all kinds of DDoS attack than any other method based on character recognition.     

基于小波域LS方法的图象超分辨率重构算法

为了能够有效地重构出高分辨率图象，提出了一种基于小波域最小二乘法(LS)的图象超分辨率重构算法．该算法是利用多尺度边缘的自相似性，由低分辨率图象通过预测来得到高分辨率图象小波变换的3个高频通道，以实现图象超分辨率重构．由于该算法保持了图象边缘附近的几何正则性，因而能够重构出较高质量的图象．同时，由于小波系数的预测只在边缘处进行，因此该算法具有较小的计算复杂度．实验表明，该算法较好地实现了图象超分辨率重构．     

背景流量仿真及其在卫星网络性能分析中的应用

研究表明网络流量具有自相似特性,而自相似网络流量的生成是网络性能分析的一个关键环节,为此设计了一种生成网络背景流量的方法。在VC++环境中对该方法进行了仿真,验证了其有效性。进一步将该方法应用于卫星网络仿真,对卫星网络端到端的延迟进行了初步分析,结果表明网络流量的突发特性影响着卫星网络的性能,这是在进行卫星网络路由优化与流量分配时需要考虑的因素。     

Self-similarity of parallel machines

Self-similarity is a property of physical systems that describes how to scale parameters such that dissimilar systems appear to be similar. Computer systems are self-similar if certain ratios of computational forces, also known as computational intensities, are equal. Two machines with different computational power, different network bandwidth and different inter-processor latency behave the same way if they have the same ratios of forces. For the parallel conjugate gradient algorithm studied in this paper, two machines are self-similar if and only if the ratio of one force describing latency effects to another force describing bandwidth effects is the same for both machines. For the two machines studied in this paper, this ratio, which we call the mixing coefficient, is invariant as problem size and processor count change. The two machines have the same mixing coefficient and belong to the same equivalence class.     

网络维数:一种度量复杂网络的新方法

如何对复杂网络进行刻画与度量,一直是人们关注的热点。在研究自相似复杂网络分形维数的基础上,提出了一种度量复杂网络的新方法——网络维数,即复杂网络边权重和的对数值与节点权重和的对数值的比值,可以将边权重及点权重推广到实数域和复数域;同时给出了不同类型权重对应的网络维数的计算方法;最后以几个代表性的经典复杂网络模型为例,讨论了所提出的网络维数的若干性质。