针对传统数值预报模式计算时间长和计算资源消耗大的问题,以及现有深度学习预报方法在温度预报结果上不精确,且预测结果模糊的问题,提出了一个新的温度预报模型。首先,设计了一个时空信息捕捉模块,将该模块捕获的长期依赖信息,作为扩散...针对传统数值预报模式计算时间长和计算资源消耗大的问题,以及现有深度学习预报方法在温度预报结果上不精确,且预测结果模糊的问题,提出了一个新的温度预报模型。首先,设计了一个时空信息捕捉模块,将该模块捕获的长期依赖信息,作为扩散模型的生成条件,赋予扩散模型预报的能力;其次,设计了一个新的平衡损失函数,同时保护了扩散模型的生成能力和时空信息捕捉模块对时空信息的捕捉能力;最后,基于美国国家环境预报中心的再分析数据进行预报,与现有的深度学习方法相比,所提模型预报结果的质量在均方误差(mean square error,MSE)上降低了17.3%,在均方根误差(root mean square error,RMSE)上降低了9.14%,在峰值信噪比(peak signal to noise ratio,PSNR)上提升了5.1%。改进的扩散模型能有效地捕捉时空依赖的关系,有效地进行时空序列预测,效果优于其他对比方法。展开更多
A calculation of the energy loss due to a transition from non-equilibrium to equilibrium state is given. Three different physical systems are considered in this study: connecting an uncharged capacitor to a charged ca...A calculation of the energy loss due to a transition from non-equilibrium to equilibrium state is given. Three different physical systems are considered in this study: connecting an uncharged capacitor to a charged capacitor, emission of a photon from an excited atom, and releasing an object from a compressed spring. In this study, it is shown that a specific fraction of the total energy stored in a non-equilibrium system should be consumed to reach the equilibrium state.展开更多
Network losses allocation is one of the major problems in the market environment. The quadric function of the injected nodal power is used in this paper as a representation for network losses, which are allocated fair...Network losses allocation is one of the major problems in the market environment. The quadric function of the injected nodal power is used in this paper as a representation for network losses, which are allocated fairly using the called market equilibrium principle while the bidding curves are corrected. The power market equilibrium is simulated as three different models that can be solved simply by the optimal power flow algorithm combining the generation scheduling problem with network losses allocation. The case study is made at an IEEE-30 nodes system and a perfect result is proved in this paper.展开更多
Potential sandy coast erosion and socio-economic impacts under sea level rise scenarios as well as socio-economic pathways were assessed in Liaodong Bay.Results show that sea level is projected to rise by 20-43 cm in ...Potential sandy coast erosion and socio-economic impacts under sea level rise scenarios as well as socio-economic pathways were assessed in Liaodong Bay.Results show that sea level is projected to rise by 20-43 cm in Liaodong Bay by 2100.And dry land loss increases in all sea level rise scenarios,with the maximum loss of 32.1 km2 in 2100 under RCP8.5.Coastal erosion results in forced migration,and the forced migration is higher under SSP3 than other pathways due to its higher population growth rate,reaching the highest of 3.1×10^4 under SSP3/RCP8.5 in 2100.Moreover,the differences of forced migration among all scenarios increas after 2050,and the migration increasing rates tend to decrease under RCP2.6 and RCP4.5.The maximum economic loss due to coastal erosion will reach 8.05 billion yuan under SSP5/RCP8.5 in 2100,in which land loss cost is two order less than migration cost,and the share of total erosion-induced economic loss in local GDP varies from 1.12‰ to 4.76‰ under all scenarios,which is an important indicator to draw local government's attention to take measures such as beach nourishment,especially for tourist beaches.Optimally,it is recommended by cost-benefit analysis to carry out nourishment mainly on beaches with high value,while there is no need for nourishment in areas where erosion impacts are negligible.展开更多
We study the high order equilibrium distributions of a counting random variable. Properties such as moments, the probability generating function, the stop--loss transform and the mean residual lifetime, are derived. E...We study the high order equilibrium distributions of a counting random variable. Properties such as moments, the probability generating function, the stop--loss transform and the mean residual lifetime, are derived. Expressions are obtained for higher order equilibrium distribution functions under mixtures and convolutions of a counting distribution. Recursive formulas for higher order equilibrium distribution functions of the (a,b,0) -family of distributions are given.展开更多
文摘针对传统数值预报模式计算时间长和计算资源消耗大的问题,以及现有深度学习预报方法在温度预报结果上不精确,且预测结果模糊的问题,提出了一个新的温度预报模型。首先,设计了一个时空信息捕捉模块,将该模块捕获的长期依赖信息,作为扩散模型的生成条件,赋予扩散模型预报的能力;其次,设计了一个新的平衡损失函数,同时保护了扩散模型的生成能力和时空信息捕捉模块对时空信息的捕捉能力;最后,基于美国国家环境预报中心的再分析数据进行预报,与现有的深度学习方法相比,所提模型预报结果的质量在均方误差(mean square error,MSE)上降低了17.3%,在均方根误差(root mean square error,RMSE)上降低了9.14%,在峰值信噪比(peak signal to noise ratio,PSNR)上提升了5.1%。改进的扩散模型能有效地捕捉时空依赖的关系,有效地进行时空序列预测,效果优于其他对比方法。
文摘A calculation of the energy loss due to a transition from non-equilibrium to equilibrium state is given. Three different physical systems are considered in this study: connecting an uncharged capacitor to a charged capacitor, emission of a photon from an excited atom, and releasing an object from a compressed spring. In this study, it is shown that a specific fraction of the total energy stored in a non-equilibrium system should be consumed to reach the equilibrium state.
文摘Network losses allocation is one of the major problems in the market environment. The quadric function of the injected nodal power is used in this paper as a representation for network losses, which are allocated fairly using the called market equilibrium principle while the bidding curves are corrected. The power market equilibrium is simulated as three different models that can be solved simply by the optimal power flow algorithm combining the generation scheduling problem with network losses allocation. The case study is made at an IEEE-30 nodes system and a perfect result is proved in this paper.
基金supported by the NMDIS Youth Fund Study on the contribution rate of sea level rise to coastal erosion of typical coastal segments(2018).
文摘Potential sandy coast erosion and socio-economic impacts under sea level rise scenarios as well as socio-economic pathways were assessed in Liaodong Bay.Results show that sea level is projected to rise by 20-43 cm in Liaodong Bay by 2100.And dry land loss increases in all sea level rise scenarios,with the maximum loss of 32.1 km2 in 2100 under RCP8.5.Coastal erosion results in forced migration,and the forced migration is higher under SSP3 than other pathways due to its higher population growth rate,reaching the highest of 3.1×10^4 under SSP3/RCP8.5 in 2100.Moreover,the differences of forced migration among all scenarios increas after 2050,and the migration increasing rates tend to decrease under RCP2.6 and RCP4.5.The maximum economic loss due to coastal erosion will reach 8.05 billion yuan under SSP5/RCP8.5 in 2100,in which land loss cost is two order less than migration cost,and the share of total erosion-induced economic loss in local GDP varies from 1.12‰ to 4.76‰ under all scenarios,which is an important indicator to draw local government's attention to take measures such as beach nourishment,especially for tourist beaches.Optimally,it is recommended by cost-benefit analysis to carry out nourishment mainly on beaches with high value,while there is no need for nourishment in areas where erosion impacts are negligible.
文摘We study the high order equilibrium distributions of a counting random variable. Properties such as moments, the probability generating function, the stop--loss transform and the mean residual lifetime, are derived. Expressions are obtained for higher order equilibrium distribution functions under mixtures and convolutions of a counting distribution. Recursive formulas for higher order equilibrium distribution functions of the (a,b,0) -family of distributions are given.
