A dominating set of a graph G is a set of vertices that contains at least one endpoint of every edge on the graph. The domination number of G is the order of a minimum dominating set of G. The (t, r) broadcast dominat...A dominating set of a graph G is a set of vertices that contains at least one endpoint of every edge on the graph. The domination number of G is the order of a minimum dominating set of G. The (t, r) broadcast domination is a generalization of domination in which a set of broadcasting vertices emits signals of strength t that decrease by 1 as they traverse each edge, and we require that every vertex in the graph receives a cumulative signal of at least r from its set of broadcasting neighbors. In this paper, we extend the study of (t, r) broadcast domination to directed graphs. Our main result explores the interval of values obtained by considering the directed (t, r) broadcast domination numbers of all orientations of a graph G. In particular, we prove that in the cases r = 1 and (t, r) = (2, 2), for every integer value in this interval, there exists an orientation of G which has directed (t, r) broadcast domination number equal to that value. We also investigate directed (t, r) broadcast domination on the finite grid graph, the star graph, the infinite grid graph, and the infinite triangular lattice graph. We conclude with some directions for future study.展开更多
本文介绍了基于Http Live Streaming的流媒体技术,包括系统架构、文件格式、数据结构和苹果提供的流媒体分割工具。结合应用场合提出了两种音视频采集方案,设计并搭建了一套基于Http Live Streaming的直播系统。分析了基于Http Live Str...本文介绍了基于Http Live Streaming的流媒体技术,包括系统架构、文件格式、数据结构和苹果提供的流媒体分割工具。结合应用场合提出了两种音视频采集方案,设计并搭建了一套基于Http Live Streaming的直播系统。分析了基于Http Live Streaming的直播系统的特点以及系统优化方向。展开更多
文摘A dominating set of a graph G is a set of vertices that contains at least one endpoint of every edge on the graph. The domination number of G is the order of a minimum dominating set of G. The (t, r) broadcast domination is a generalization of domination in which a set of broadcasting vertices emits signals of strength t that decrease by 1 as they traverse each edge, and we require that every vertex in the graph receives a cumulative signal of at least r from its set of broadcasting neighbors. In this paper, we extend the study of (t, r) broadcast domination to directed graphs. Our main result explores the interval of values obtained by considering the directed (t, r) broadcast domination numbers of all orientations of a graph G. In particular, we prove that in the cases r = 1 and (t, r) = (2, 2), for every integer value in this interval, there exists an orientation of G which has directed (t, r) broadcast domination number equal to that value. We also investigate directed (t, r) broadcast domination on the finite grid graph, the star graph, the infinite grid graph, and the infinite triangular lattice graph. We conclude with some directions for future study.
文摘本文介绍了基于Http Live Streaming的流媒体技术,包括系统架构、文件格式、数据结构和苹果提供的流媒体分割工具。结合应用场合提出了两种音视频采集方案,设计并搭建了一套基于Http Live Streaming的直播系统。分析了基于Http Live Streaming的直播系统的特点以及系统优化方向。