The distribution performance of the gravity-type liquid distributor(GTLD) significantly affects column operation efficiency and the consequent product quality. In industrial settings, maldistribution is normally consi...The distribution performance of the gravity-type liquid distributor(GTLD) significantly affects column operation efficiency and the consequent product quality. In industrial settings, maldistribution is normally considered to be caused by vertical positional or coplanarity errors stemming from deflections associated with manufacture and installation, or even by excessive weight. The lack ofestimation protocols or standards impedes the description ofthis error, which influences the corresponding outflow rates. Given this situation, the paper proposes a lumped parameter, orifice position deviation(OPD), to facilitate the calculation of the relative discharge rate error(RDRE)based on a formula derivation, which allows the systematic analysis of the influence ofa single orifice or weir OPD.The paper introduces a sensitivity factor K as a concise and unified expression in theoretical RDREs for calibrating the influence of OPD on the RDREs ofgeometrically different orifices and weirs. With respect to the GTLD, a larger K indicates the need for more strict OPD requirements. The paper verifies that the extent of GTLD outflow nonuniformity is associated with diverging tendencies regarding its morphology, especially in the orifice and weir, which can be determined using our proposed procedures.展开更多
Aim To study properties of solutions to a class of second order differential inequality with continuous distributed deviating arguments. Methods A direct analysis technique was used. Results and Conclusion Some suf...Aim To study properties of solutions to a class of second order differential inequality with continuous distributed deviating arguments. Methods A direct analysis technique was used. Results and Conclusion Some sufficient conditions that ensure a class of second order delay differential inequality having no eventually positive solutions were obtained, which generalized some given results. Using the results, some oscillatory criteria for solutions of the hyperbolic equation with distributed deviating arguments can be established.展开更多
In the vehicle trajectory application system, it is often necessary to detect whether the vehicle deviates from the specified route. Trajectory planning in the traditional route deviation detection is defined by the d...In the vehicle trajectory application system, it is often necessary to detect whether the vehicle deviates from the specified route. Trajectory planning in the traditional route deviation detection is defined by the driver through the mobile phone navigation software, which plays a more auxiliary driving role. This paper presents a method of vehicle trajectory deviation detection. Firstly, the manager customizes the trajectory planning and then uses big data technologies to match the deviation between the trajectory planning and the vehicle trajectory. Finally, it achieves the supervisory function of the manager on the vehicle track route in real-time. The results show that this method could detect the vehicle trajectory deviation quickly and accurately, and has practical application value.展开更多
在室内定位系统中,基于Wi-Fi技术的定位精度很大程度上依赖于信号的稳定,信号的多径效应与非视距(Non Line of Sight,NLOS)会增大定位误差。行人航位推算(Pedestrian Dead Reckoning,PDR)定位系统会因传感器自身误差与噪声产生累计误差...在室内定位系统中,基于Wi-Fi技术的定位精度很大程度上依赖于信号的稳定,信号的多径效应与非视距(Non Line of Sight,NLOS)会增大定位误差。行人航位推算(Pedestrian Dead Reckoning,PDR)定位系统会因传感器自身误差与噪声产生累计误差。针对上述问题,提出了一种改进的PDR与最小一乘法(Least Absolute Deviation,LAD)融合的室内定位算法。该算法基于模糊逻辑将PDR算法的步长固定参数改进为变量参数,同时根据LAD的定位结果对PDR进行周期性位置与拐点位置校正,选择扩展卡尔曼滤波(Extend Kalman Filter,EKF)将改进的PDR与LAD进行融合,以降低PDR的累计误差与LAD的突变误差,提高定位精度。实验结果表明:所提方法较其他方法具有更高的定位精度。展开更多
文摘The distribution performance of the gravity-type liquid distributor(GTLD) significantly affects column operation efficiency and the consequent product quality. In industrial settings, maldistribution is normally considered to be caused by vertical positional or coplanarity errors stemming from deflections associated with manufacture and installation, or even by excessive weight. The lack ofestimation protocols or standards impedes the description ofthis error, which influences the corresponding outflow rates. Given this situation, the paper proposes a lumped parameter, orifice position deviation(OPD), to facilitate the calculation of the relative discharge rate error(RDRE)based on a formula derivation, which allows the systematic analysis of the influence ofa single orifice or weir OPD.The paper introduces a sensitivity factor K as a concise and unified expression in theoretical RDREs for calibrating the influence of OPD on the RDREs ofgeometrically different orifices and weirs. With respect to the GTLD, a larger K indicates the need for more strict OPD requirements. The paper verifies that the extent of GTLD outflow nonuniformity is associated with diverging tendencies regarding its morphology, especially in the orifice and weir, which can be determined using our proposed procedures.
文摘Aim To study properties of solutions to a class of second order differential inequality with continuous distributed deviating arguments. Methods A direct analysis technique was used. Results and Conclusion Some sufficient conditions that ensure a class of second order delay differential inequality having no eventually positive solutions were obtained, which generalized some given results. Using the results, some oscillatory criteria for solutions of the hyperbolic equation with distributed deviating arguments can be established.
文摘In the vehicle trajectory application system, it is often necessary to detect whether the vehicle deviates from the specified route. Trajectory planning in the traditional route deviation detection is defined by the driver through the mobile phone navigation software, which plays a more auxiliary driving role. This paper presents a method of vehicle trajectory deviation detection. Firstly, the manager customizes the trajectory planning and then uses big data technologies to match the deviation between the trajectory planning and the vehicle trajectory. Finally, it achieves the supervisory function of the manager on the vehicle track route in real-time. The results show that this method could detect the vehicle trajectory deviation quickly and accurately, and has practical application value.
文摘在室内定位系统中,基于Wi-Fi技术的定位精度很大程度上依赖于信号的稳定,信号的多径效应与非视距(Non Line of Sight,NLOS)会增大定位误差。行人航位推算(Pedestrian Dead Reckoning,PDR)定位系统会因传感器自身误差与噪声产生累计误差。针对上述问题,提出了一种改进的PDR与最小一乘法(Least Absolute Deviation,LAD)融合的室内定位算法。该算法基于模糊逻辑将PDR算法的步长固定参数改进为变量参数,同时根据LAD的定位结果对PDR进行周期性位置与拐点位置校正,选择扩展卡尔曼滤波(Extend Kalman Filter,EKF)将改进的PDR与LAD进行融合,以降低PDR的累计误差与LAD的突变误差,提高定位精度。实验结果表明:所提方法较其他方法具有更高的定位精度。
