工业物联网(Industrial Internet of Things,IIoT)可以将各种工业设备、监测仪表以及传感器进行相互连接,设备的运行状态可通过监测仪表与传感器进行全面感知,并根据感知数据对设备状态进行分析与预测。然而要对海量的感知数据进行分析...工业物联网(Industrial Internet of Things,IIoT)可以将各种工业设备、监测仪表以及传感器进行相互连接,设备的运行状态可通过监测仪表与传感器进行全面感知,并根据感知数据对设备状态进行分析与预测。然而要对海量的感知数据进行分析处理需要大量的存储空间与计算能力,将其传送到云平台势必将占用大量的带宽并产生较大的时延,很难满足对设备状态实时分析与诊断的需求。因此,针对工业设备状态感知的数据,提出了基于最优差分和线性拟合降熵变换的无损压缩方法,在数据采集的边缘侧对感知数据进行无损压缩,从而大大提高传输效率,使得感知数据能快速传送到云平台进行分析与处理。该方法根据数据差值序列方差大小和采集频率高低从最优差分和曲线拟合差值中选取有效的降熵变换进行压缩,并采用LZO(Lempel-Ziv-Oberhumer)压缩算法进行二次压缩。在两类不同的数据集上对所提方法进行了测试,实验结果表明,该方法的压缩率最低与最高分别可达77%和93%,同时验证了其无损重构的特性。展开更多
Subgrade settlement is a common issue in soil ground within earthquake-prone regions,posing a threat to the safe operation of train-slab track coupled system(TSCS)in high-speed railways(HSRs).This study aims to analyz...Subgrade settlement is a common issue in soil ground within earthquake-prone regions,posing a threat to the safe operation of train-slab track coupled system(TSCS)in high-speed railways(HSRs).This study aims to analyze the mechanical behavior evolution of TSCS under subgrade settlement and earthquake excitation.The refined numerical model of slab track under subgrade differential settlement is established.The short settlement wavelength of 10 m causes the separation between the base and subgrade.The dynamic model of TSCS under subgrade settlement and earthquake excitation is developed.The dynamic response of TSCS exhibits more pronounced fluctuations under the combined effects of subgrade settlement and earthquake excitation than under the effects of settlement or earthquake alone.The evaluation indexes for the running safety of train on slab track under different settlement wavelengths exhibit varying degrees of increase with settlement amplitude and are particularly sensitive to the short settlement wavelength of 10 m.The wheel unloading rate and derailment coefficient of TSCS increase with earthquake intensity.Under the settlement wavelength of 10 m and amplitude of 20 mm,the wheel unloading rate of TSCS exceeds the allowable limit when the earthquake intensity exceeds 0.17g,and the derailment coefficient exceeds the allowable limit when the earthquake intensity surpasses 0.29g.展开更多
文摘工业物联网(Industrial Internet of Things,IIoT)可以将各种工业设备、监测仪表以及传感器进行相互连接,设备的运行状态可通过监测仪表与传感器进行全面感知,并根据感知数据对设备状态进行分析与预测。然而要对海量的感知数据进行分析处理需要大量的存储空间与计算能力,将其传送到云平台势必将占用大量的带宽并产生较大的时延,很难满足对设备状态实时分析与诊断的需求。因此,针对工业设备状态感知的数据,提出了基于最优差分和线性拟合降熵变换的无损压缩方法,在数据采集的边缘侧对感知数据进行无损压缩,从而大大提高传输效率,使得感知数据能快速传送到云平台进行分析与处理。该方法根据数据差值序列方差大小和采集频率高低从最优差分和曲线拟合差值中选取有效的降熵变换进行压缩,并采用LZO(Lempel-Ziv-Oberhumer)压缩算法进行二次压缩。在两类不同的数据集上对所提方法进行了测试,实验结果表明,该方法的压缩率最低与最高分别可达77%和93%,同时验证了其无损重构的特性。
基金国家自然科学基金资助项目(51178469),National Natural Science Foundation of China(51178469)中南大学中央高校基本科研业务费专项资金资助项目(2017ZZTS593),Fundamental Research Funds for the Central Universities of Central South University(2017ZZTS593)国家自然科学基金高速铁路基础研究联合基金资助项目(U1334203,U1134209)
基金Project(52078501)supported by the National Natural Science Foundation of ChinaProject(2022-Major-14)supported by the Science and Technology Research and Development Program Project of China Railway Group LimitedProject(2023ZZTS0342)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Subgrade settlement is a common issue in soil ground within earthquake-prone regions,posing a threat to the safe operation of train-slab track coupled system(TSCS)in high-speed railways(HSRs).This study aims to analyze the mechanical behavior evolution of TSCS under subgrade settlement and earthquake excitation.The refined numerical model of slab track under subgrade differential settlement is established.The short settlement wavelength of 10 m causes the separation between the base and subgrade.The dynamic model of TSCS under subgrade settlement and earthquake excitation is developed.The dynamic response of TSCS exhibits more pronounced fluctuations under the combined effects of subgrade settlement and earthquake excitation than under the effects of settlement or earthquake alone.The evaluation indexes for the running safety of train on slab track under different settlement wavelengths exhibit varying degrees of increase with settlement amplitude and are particularly sensitive to the short settlement wavelength of 10 m.The wheel unloading rate and derailment coefficient of TSCS increase with earthquake intensity.Under the settlement wavelength of 10 m and amplitude of 20 mm,the wheel unloading rate of TSCS exceeds the allowable limit when the earthquake intensity exceeds 0.17g,and the derailment coefficient exceeds the allowable limit when the earthquake intensity surpasses 0.29g.
