您当前所在位置: 首页 > 学者
为您找到 3 条相关结果
按相关度
  • 按相关度
  • 按时间
  • 按阅读量
  • 代表性成果优先

上传时间

2015年05月05日

【期刊论文】Social Group Search Optimizer Algorithm for Ad Hoc Network

冯翔, 马美怡, 虞慧群, 王喆

Ad Hoc & Sensor Wireless Networks,2015,28((3-4)):257-287

2015年01月01日

摘要

Due to the dynamic structure in network topology and absence of a centralized administration in management, a specific routing algorithm satisfying the demands of QoS is required indeed in mobile Ad Hoc networks. A novel Social Group Search Optimizer algorithm is pro-posed by improving the GSO algorithm to a dynamic and discrete algorithm through the introducing of social behaviors. SGSO is divided into search and prey parts, where “search” is on duty to find the optimal solution effectively and “prey” is responsible for adjusting the algorithm to the dynamic change of objective functions. Dynamic Coupling Level is used to divide the Ad Hoc network and corresponding approaches and models based on SGSO are applied to routing algorithm, including the decision factor and local routing table. The convergence and correctness of our algorithm are verified mathematically and extensive experiments have been conducted to evaluate the efficiency and effectiveness of the proposed mechanism in mobile Ad Hoc networks. The results show that SGSO improves packet delivery ratio and reduces average end-to-end latency effectively, especially for large-scale and high-dynamicnetworks.

关键词: Ad Hoc network,, ocial behavior,, social group searching optimization, dynamic network,, quality of service

  • 37浏览

  • 0点赞

  • 0收藏

  • 0分享

  • 16下载

  • 0评论

  • 引用

上传时间

2018年06月26日

【期刊论文】The regional features of temperature variation trends over Xinjiang in China by the ensemble empirical mode decomposition method

Ling Bai, Jianhua Xu, Zhongsheng Chen, Weihong Li

International Journal of Climatology,2015,35(11):3229-3237

2015年11月11日

摘要

Based on a temperature anomaly time series from 16 international exchange stations in Xinjiang from 1957 to 2012, the multi‐scale characteristics of temperature variability were analysed using the ensemble empirical mode decomposition (EEMD) method. Regional differences in variation trends and change‐points were also preliminarily discussed. The results indicated that in the past 50+ years, the overall temperature in Xinjiang has exhibited a significant nonlinear upward trend, and its changes have clearly exhibited an inter‐annual scale (quasi‐3 and quasi‐6‐year) and inter‐decadal scale (quasi‐10 and quasi‐30‐year). The variance contribution rates of each component demonstrated that the inter‐annual change had a strong influence on the overall temperature change in Xinjiang, and the reconstructed inter‐annual variation trend could describe the fluctuation state of the original temperature anomaly during the study period. The reconstructed inter‐decadal variability revealed that the climate mode in Xinjiang had a significant transformation before and after 1995, namely the temperature anomaly shift from a negative phase to a positive one. Furthermore, there were regional differences in the nonlinear changes and change‐points of temperature. At the same time, the results also suggested that the EEMD method can effectively reveal variations in long‐term temperature sequences at different time scales and can be used for the complex diagnosis of nonlinear and non‐stationary signal changes.

关键词: Temperature variation, Xinjiang,, China, Ensemble empirical mode decomposition

  • 52浏览

  • 0点赞

  • 0收藏

  • 0分享

  • 0下载

  • 0评论

  • 引用

上传时间

2019年05月03日

【期刊论文】On the ill-posedness of the compressible Navier-Stokes equations in the critical Besov spaces

Qionglei Chen, Changxing Miao, Zhifei Zhang

Revista Matemtica Iberoamericana, ,2015,31(4):1375–1402

2015年12月01日

摘要

We prove the ill-posedness of the 3-D baratropic Navier-Stokes equation for the initial density and velocity belonging to the critical Besov space $(\dot{B}^{\f 3p}_{p,1}+\bar{\rho},\,\dot{B}^{\f 3p-1}_{p,1})$ for $p>6$ in the sense that a ``norm inflation" happens in finite time, here $\bar{\rho}$ is a positive constant. While, the compressible viscous heat-conductive flows is ill-posed for the initial density, velocity and temperature belonging to the critical Besov space $(\dot{B}^{\f 3p}_{p,1}+\bar{\rho},\,\dot{B}^{\f 3p-1}_{p,1},\,\dot{B}^{\f 3p-2}_{p,1})$ for $p>3$.

关键词: Compressible Navier–Stokes equations,, ill-posedness,, Besov space

  • 44浏览

  • 0点赞

  • 0收藏

  • 0分享

  • 0下载

  • 0评论

  • 引用