Research on clustering coefficient in RGG model of wireless Ad Hoc network

在影响无线网络同步的因素中,网络拓扑结构逐渐引起人们的关注。通过研究rgg模型中网络聚类系数和网络次大特征值之间的关系,来探索聚类系数对网络收敛性能的影响程度,并希望从有边界效应和无边界效应两种情况入手对其进行研究。通过仿真实验发现在无边界情况下的聚类系数是一个常数,与其他因素无关,有边界情况下其值与环境参数相关。从理论上推导了无边界聚类系数的理论值,并给出了有边界情况下的推导思路。In the factors that affect wireless network synchronization,the network topology structure gradually draws attention of researchers.By studying the relationship between network clustering coefficient and the secondary largest eigenvalue in RGG model,the effect of network clustering coefficient on network convergence performance was explored under two conditions with and without boundary effect.Through the simulation,it is found that the clustering coefficient under the borderless condition is a constant,which is not related to other factors,and the clustering coefficient with boundary effect is related to the environment parameter.The theoretical value of clustering coefficient without boundary effect is derived theoretically.The thought of derivation with boundary effect is offered.国家自然科学基金(61201196); 教育部博士点基金(20100121120020); 福建省自然科学基金(2012J05127

Resarch on Co-Synchronization Method and Channel Access Technology in Wireless Ad hoc Networks

摘要 无线自组织网络（Adhoc）是一种无中心、多跳、分布式部署的无线网络，具有可快速、独立组网的特点。无线自组织网络的通信节点之间独立平等，无需固定设备支持，因此抗毁能力较强，可适应多种情况需求，具有广阔的应用前景。 无线自组织网络的信道接入（MediaAccessControl）协议掌管节点如何获取信道，对网络性能有着重大影响。和基于竞争的协议相比，基于时分的接入协议有着时延可控、无冲突传输等优势。但在提高基于时分的接入协议性能时，仍有两个难点需要解决：如何保证全网时间同步以及如何提高网络吞吐率。在基于时分的分布式协议中，时间同步是实现其他功能的重要前提，因此研究网络的同步速率具有重大...Abstract Wireless ad hoc is a distributed wireless multi-hop network with no-central node and distributed deployment, which has a rapit and dependent characteristic.The nodes in Ad hoc are equal and independent, without supporting from fixed equipments. As a result, they has a strong anti-damage ability and can satisfy the needs of many kinds of situations, which can make it has a broad applicati...学位：工学硕士院系专业：信息科学与技术学院_通信与信息系统学号：2332011115314

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel