In this paper, a singularly perturbed boundary value problem for second order self-adjoint ordinary differential equation is discussed. A class of variational difference schemes is constructed by the finite element me...In this paper, a singularly perturbed boundary value problem for second order self-adjoint ordinary differential equation is discussed. A class of variational difference schemes is constructed by the finite element method. Uniform convergence about small parameter is proved under a weaker smooth condition with respect to the coefficients of the equation. The schemes studied in refs. [1], [3], [4] and [51 belong to the cllass.展开更多
This paper proposes a new queuing model and adaptive scheduling scheme which realizes multi-class QoS mechanism under DiffServ architecture. The queuing model is composed of two parallel output subqueues, each output ...This paper proposes a new queuing model and adaptive scheduling scheme which realizes multi-class QoS mechanism under DiffServ architecture. The queuing model is composed of two parallel output subqueues, each output sub-queue adopts random drop algorithm by setting different buffer threshold for different class traffic, so it can provide multi-class QoS. The new proposed scheduling scheme which adaptively changes the parameter A can guarantee the performance target of high class traffic, in the mean time, improve the QoS of low classes traffic.展开更多
To assure the shareholders can look for their "legal" attorneys to renew the secret, once the secret sharing scheme is initialized, a secret sharing scheme with inherited characteristic is constructed. In this schem...To assure the shareholders can look for their "legal" attorneys to renew the secret, once the secret sharing scheme is initialized, a secret sharing scheme with inherited characteristic is constructed. In this scheme, each shareholder can produce a new share by his algorithm, which is equivalent to the primary one. Together with other shares, the primary secret can be renewed. Since this scheme is constructed not by replacing the primary share with a new share produced by the dealer in his primitive secret sharing scheme, so no matter how much shares the shareholder produces, these shares can not be gathered together to renew the secret in this scheme. Compared with the existing secret sharing schemes, this scheme provides more agility for the shareholders by investing each of them a function but not affect its security.展开更多
韩国政府实施的《世界一流大学(WCU,World Class University)建设计划》人文社会科学领域的评价指标体系具有注重区分项目类别,引入国际同行评议,定性和定量评价相结合,注重教育教学和科学研究实绩,对外籍专家学者管理模式灵活而人性化...韩国政府实施的《世界一流大学(WCU,World Class University)建设计划》人文社会科学领域的评价指标体系具有注重区分项目类别,引入国际同行评议,定性和定量评价相结合,注重教育教学和科学研究实绩,对外籍专家学者管理模式灵活而人性化等特点。结合韩国《世界一流大学(WCU)建设计划》实施实际,建议国内的双一流建设工作需要重点关注构建经常性的信息收集体系,注重定性定量相结合,考虑专业学科特点,处理好引进人才与本土化人才培养。展开更多
This study incorporated the Weather Research and Forecasting(WRF) model double-moment 6-class(WDM6) microphysics scheme into the mesoscale version of the Global/Regional Assimilation and Pr Ediction System(GRAPES...This study incorporated the Weather Research and Forecasting(WRF) model double-moment 6-class(WDM6) microphysics scheme into the mesoscale version of the Global/Regional Assimilation and Pr Ediction System(GRAPES_Meso). A rainfall event that occurred during 3–5 June 2015 around Beijing was simulated by using the WDM6, the WRF single-moment 6-class scheme(WSM6), and the NCEP 5-class scheme, respectively. The results show that both the distribution and magnitude of the rainfall simulated with WDM6 were more consistent with the observation. Compared with WDM6, WSM6 simulated larger cloud liquid water content, which provided more water vapor for graupel growth, leading to increased precipitation in the cold-rain processes. For areas with the warmrain processes, the sensitivity experiments using WDM6 showed that an increase in cloud condensation nuclei(CCN)number concentration led to enhanced CCN activation ratio and larger cloud droplet number concentration(Nc) but decreased cloud droplet effective diameter. The formation of more small-size cloud droplets resulted in a decrease in raindrop number concentration(Nr), inhibiting the warm-rain processes, thus gradually decreasing the amount of precipitation. For areas mainly with the cold-rain processes, the overall amount of precipitation increased; however, it gradually decreased when the CCN number concentration reached a certain magnitude. Hence, the effect of CCN number concentration on precipitation exhibits significant differences in different rainfall areas of the same precipitation event.展开更多
文摘In this paper, a singularly perturbed boundary value problem for second order self-adjoint ordinary differential equation is discussed. A class of variational difference schemes is constructed by the finite element method. Uniform convergence about small parameter is proved under a weaker smooth condition with respect to the coefficients of the equation. The schemes studied in refs. [1], [3], [4] and [51 belong to the cllass.
文摘This paper proposes a new queuing model and adaptive scheduling scheme which realizes multi-class QoS mechanism under DiffServ architecture. The queuing model is composed of two parallel output subqueues, each output sub-queue adopts random drop algorithm by setting different buffer threshold for different class traffic, so it can provide multi-class QoS. The new proposed scheduling scheme which adaptively changes the parameter A can guarantee the performance target of high class traffic, in the mean time, improve the QoS of low classes traffic.
基金This project was supported by Young Teacher Foundation of North China Elec. Power Univ.(200521001)
文摘To assure the shareholders can look for their "legal" attorneys to renew the secret, once the secret sharing scheme is initialized, a secret sharing scheme with inherited characteristic is constructed. In this scheme, each shareholder can produce a new share by his algorithm, which is equivalent to the primary one. Together with other shares, the primary secret can be renewed. Since this scheme is constructed not by replacing the primary share with a new share produced by the dealer in his primitive secret sharing scheme, so no matter how much shares the shareholder produces, these shares can not be gathered together to renew the secret in this scheme. Compared with the existing secret sharing schemes, this scheme provides more agility for the shareholders by investing each of them a function but not affect its security.
文摘韩国政府实施的《世界一流大学(WCU,World Class University)建设计划》人文社会科学领域的评价指标体系具有注重区分项目类别,引入国际同行评议,定性和定量评价相结合,注重教育教学和科学研究实绩,对外籍专家学者管理模式灵活而人性化等特点。结合韩国《世界一流大学(WCU)建设计划》实施实际,建议国内的双一流建设工作需要重点关注构建经常性的信息收集体系,注重定性定量相结合,考虑专业学科特点,处理好引进人才与本土化人才培养。
基金Supported by the National Key Project(2016YFC0203306)National Natural Science Foundation of China(41590874)+2 种基金National(Key)973 Program(2014CB441201)Chinese Academy of Meteorological Sciences’ Project(2017Z001)Key Project of Air Pollution Cause and Control(DQGG0104)
文摘This study incorporated the Weather Research and Forecasting(WRF) model double-moment 6-class(WDM6) microphysics scheme into the mesoscale version of the Global/Regional Assimilation and Pr Ediction System(GRAPES_Meso). A rainfall event that occurred during 3–5 June 2015 around Beijing was simulated by using the WDM6, the WRF single-moment 6-class scheme(WSM6), and the NCEP 5-class scheme, respectively. The results show that both the distribution and magnitude of the rainfall simulated with WDM6 were more consistent with the observation. Compared with WDM6, WSM6 simulated larger cloud liquid water content, which provided more water vapor for graupel growth, leading to increased precipitation in the cold-rain processes. For areas with the warmrain processes, the sensitivity experiments using WDM6 showed that an increase in cloud condensation nuclei(CCN)number concentration led to enhanced CCN activation ratio and larger cloud droplet number concentration(Nc) but decreased cloud droplet effective diameter. The formation of more small-size cloud droplets resulted in a decrease in raindrop number concentration(Nr), inhibiting the warm-rain processes, thus gradually decreasing the amount of precipitation. For areas mainly with the cold-rain processes, the overall amount of precipitation increased; however, it gradually decreased when the CCN number concentration reached a certain magnitude. Hence, the effect of CCN number concentration on precipitation exhibits significant differences in different rainfall areas of the same precipitation event.