The effect of delay time on photoelectron spectra and state populations of a four-level ladder K2 molecule is investigated by a pump1–pump2–probe pulse via the time-dependent wave packet approach. The periodical mot...The effect of delay time on photoelectron spectra and state populations of a four-level ladder K2 molecule is investigated by a pump1–pump2–probe pulse via the time-dependent wave packet approach. The periodical motion of the wave packet leads to the periodical change of the photoelectron spectra. The Autler–Townes triple splitting appears at zero delay time, double splitting appears at nonzero delay time between pump1 and pump2 pulses, and no splitting appears at nonzero delay time between pump2 and probe pulses. The periodical change of the state populations with the delay time may be due to the coupling effect between the two pulses. It is found that the selectivity of the state populations may be attained by regulating the delay time. The results can provide an important basis for realizing the optical control of molecules experimentally.展开更多
文章针对通信电源系统易受多种因素影响的特点,开发了一种基于高级精简指令集计算机机器(Advanced Reduced Instruction Set Computer Machines,ARM)核心控制芯片和通用分组无线业务(General Packet Radio Service,GPRS)数据传输单元(Da...文章针对通信电源系统易受多种因素影响的特点,开发了一种基于高级精简指令集计算机机器(Advanced Reduced Instruction Set Computer Machines,ARM)核心控制芯片和通用分组无线业务(General Packet Radio Service,GPRS)数据传输单元(Data Transfer Unit,DTU)模块的实时监测系统。系统通过现场控制终端采集通信电源设备的运行状态信息,经模拟数字(Analog to Digital,AD)转换模块处理后,由ARM核心控制芯片发送至无线模块,最终传输至远程监控中心。此外,设计一套应急预案,包括应急预案设计原则、组织机构与职责、应急分级、启动条件与工作流程以及保障措施等,以应对电网大停电带来的经济损失。通过技术保障、装备保障、人员保障,实现抢修工作的快速响应,缩短断电时间,有效减少经济损失,确保生产生活不受影响。展开更多
This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktis...This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktispan the smallestone. Three situations with展开更多
针对轴承故障特征提取能力不足、源域与目标域数据分布差异过大等问题,本文提出了一种基于小波包域对抗注意力迁移学习的故障诊断方法(WWRESE-IDALM)。首先,通过小波包变换(Wavelet Packet Transform,WPT)获得不同重点节构的时频域信息...针对轴承故障特征提取能力不足、源域与目标域数据分布差异过大等问题,本文提出了一种基于小波包域对抗注意力迁移学习的故障诊断方法(WWRESE-IDALM)。首先,通过小波包变换(Wavelet Packet Transform,WPT)获得不同重点节构的时频域信息;其次,将重构后的时频域信息数据经过一层大卷积核和通道注意力模块(Squeeze and Excitation,SE)提取轴承深度关键信息特征;利用改进的域对抗网络(Domain-Adversarial Training of Neural Networks,DANN)和局部最大平均差异(Local Maximum Mean Discrepancy,LMMD)对齐子域分布,减少相关子域和全局域之间的结构差异;最后,通过标签分类网络完成故障分类。在帕德博恩大学轴承数据集诊断结果证明了所提出的WWRESE-IDALM方法具有良好的变工况故障分类能力。展开更多
利用多路径传输协议,多宿主主机可以通过多条路径并行传输数据,从而有效提高系统的吞吐率和鲁棒性.但是由于不同路径在带宽、延迟和丢包率等方面存在差异,接收端必须缓存大量乱序到达的分组.数学分析表明,减少接收端的缓存开销有两条途...利用多路径传输协议,多宿主主机可以通过多条路径并行传输数据,从而有效提高系统的吞吐率和鲁棒性.但是由于不同路径在带宽、延迟和丢包率等方面存在差异,接收端必须缓存大量乱序到达的分组.数学分析表明,减少接收端的缓存开销有两条途径:一是最小化每条路径的发送队列中积压分组的数量,二是降低分组发送速率.由前者,提出依据每条路径的空闲发送窗口大小进行分组调度的算法SOD(Scheduling On Demand);由后者,提出利用窗口通告机制限制分组发送速率的流控方法.模拟实验结果表明:与现有算法相比,SOD的缓存开销最小;在接收端进行流控限制的情况下,SOD的吞吐率最大,并且在不同实验场景中性能表现稳定.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11704178 and 11764041)the Scientific Research Fund of Hunan Provincial Education Department,China(Grant No.15B204)
文摘The effect of delay time on photoelectron spectra and state populations of a four-level ladder K2 molecule is investigated by a pump1–pump2–probe pulse via the time-dependent wave packet approach. The periodical motion of the wave packet leads to the periodical change of the photoelectron spectra. The Autler–Townes triple splitting appears at zero delay time, double splitting appears at nonzero delay time between pump1 and pump2 pulses, and no splitting appears at nonzero delay time between pump2 and probe pulses. The periodical change of the state populations with the delay time may be due to the coupling effect between the two pulses. It is found that the selectivity of the state populations may be attained by regulating the delay time. The results can provide an important basis for realizing the optical control of molecules experimentally.
文摘文章针对通信电源系统易受多种因素影响的特点,开发了一种基于高级精简指令集计算机机器(Advanced Reduced Instruction Set Computer Machines,ARM)核心控制芯片和通用分组无线业务(General Packet Radio Service,GPRS)数据传输单元(Data Transfer Unit,DTU)模块的实时监测系统。系统通过现场控制终端采集通信电源设备的运行状态信息,经模拟数字(Analog to Digital,AD)转换模块处理后,由ARM核心控制芯片发送至无线模块,最终传输至远程监控中心。此外,设计一套应急预案,包括应急预案设计原则、组织机构与职责、应急分级、启动条件与工作流程以及保障措施等,以应对电网大停电带来的经济损失。通过技术保障、装备保障、人员保障,实现抢修工作的快速响应,缩短断电时间,有效减少经济损失,确保生产生活不受影响。
文摘This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktispan the smallestone. Three situations with
文摘针对轴承故障特征提取能力不足、源域与目标域数据分布差异过大等问题,本文提出了一种基于小波包域对抗注意力迁移学习的故障诊断方法(WWRESE-IDALM)。首先,通过小波包变换(Wavelet Packet Transform,WPT)获得不同重点节构的时频域信息;其次,将重构后的时频域信息数据经过一层大卷积核和通道注意力模块(Squeeze and Excitation,SE)提取轴承深度关键信息特征;利用改进的域对抗网络(Domain-Adversarial Training of Neural Networks,DANN)和局部最大平均差异(Local Maximum Mean Discrepancy,LMMD)对齐子域分布,减少相关子域和全局域之间的结构差异;最后,通过标签分类网络完成故障分类。在帕德博恩大学轴承数据集诊断结果证明了所提出的WWRESE-IDALM方法具有良好的变工况故障分类能力。
文摘利用多路径传输协议,多宿主主机可以通过多条路径并行传输数据,从而有效提高系统的吞吐率和鲁棒性.但是由于不同路径在带宽、延迟和丢包率等方面存在差异,接收端必须缓存大量乱序到达的分组.数学分析表明,减少接收端的缓存开销有两条途径:一是最小化每条路径的发送队列中积压分组的数量,二是降低分组发送速率.由前者,提出依据每条路径的空闲发送窗口大小进行分组调度的算法SOD(Scheduling On Demand);由后者,提出利用窗口通告机制限制分组发送速率的流控方法.模拟实验结果表明:与现有算法相比,SOD的缓存开销最小;在接收端进行流控限制的情况下,SOD的吞吐率最大,并且在不同实验场景中性能表现稳定.
