The problems of airport landside capacity assessment are of industry-wide interest. Evaluation of landside capacity enables airport operators and airport designers to identify passenger and baggage flow bottlenecks, i...The problems of airport landside capacity assessment are of industry-wide interest. Evaluation of landside capacity enables airport operators and airport designers to identify passenger and baggage flow bottlenecks, identify the primary cause of bottlenecks formation and take measures mitigating the impact of bottlenecks on the airport terminal operation. Many studies dealing with the problems of airport landside capacity are focused mainly on the processing part of the airport terminal and consider the airport terminal to be an isolated system. Even the most of models of airport landside operations developed using various simulation （both generic and dedicated） software packages （e.g., PaxSim, SLAM, WITNESS, ARENA or EXTEND） are designed for simulating the passenger and baggage flows only between curb-side and apron. Although this approach provides valuable data concerning capacity, delays or processing bottlenecks, in some cases identified capacity constraints are only the symptoms of the actual problem. In order to discover the cause of the problem, it is necessary to consider the airport terminal as an integral part of much more complex regional, national or international transportation system. This article reflects the above mentioned requirements and introduces an innovative approach to passenger and baggage flow simulation based on the fact that airport terminal is considered as an integral part of air passenger door-to-door transportation process.展开更多
The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process th...The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance.展开更多
导航系统依赖传感器感知周围环境。当前,基于单一传感器的导航系统已难以满足各类复杂场景下的导航需求,导航系统正朝传感器多源化方向发展。在多源传感器数据融合过程中,图像数据的处理最消耗时间和资源,对系统性能影响最大。为解决这...导航系统依赖传感器感知周围环境。当前,基于单一传感器的导航系统已难以满足各类复杂场景下的导航需求,导航系统正朝传感器多源化方向发展。在多源传感器数据融合过程中,图像数据的处理最消耗时间和资源,对系统性能影响最大。为解决这些问题,设计智能导航平台的硬件控制终端,利用基于全球卫星导航系统(Global Navigation Satellite System,GNSS)秒脉冲(Pulse Per Second,PPS)的时间同步,实现多源传感器数据融合;设计用于同步定位与地图构建(Simultaneous Localization And Mapping,SLAM)前端ORB(Oriented FAST and Rotated BRIEF)特征提取加速器,加速图像处理过程,提高SLAM系统的实时性。实验结果表明,硬件平台不仅支持GNSS、惯性测量单元(Inertial Measurement Unit,IMU)、视觉和激光雷达的数据采集和融合,还能加速图像ORB特征点提取。在执行图像ORB特征提取任务时,与CPU和GPU平台上的实现相比,该加速器的帧率分别达到了它们的2.7倍和1.8倍,而功耗仅为它们的5.1%和2.9%。展开更多
文摘The problems of airport landside capacity assessment are of industry-wide interest. Evaluation of landside capacity enables airport operators and airport designers to identify passenger and baggage flow bottlenecks, identify the primary cause of bottlenecks formation and take measures mitigating the impact of bottlenecks on the airport terminal operation. Many studies dealing with the problems of airport landside capacity are focused mainly on the processing part of the airport terminal and consider the airport terminal to be an isolated system. Even the most of models of airport landside operations developed using various simulation （both generic and dedicated） software packages （e.g., PaxSim, SLAM, WITNESS, ARENA or EXTEND） are designed for simulating the passenger and baggage flows only between curb-side and apron. Although this approach provides valuable data concerning capacity, delays or processing bottlenecks, in some cases identified capacity constraints are only the symptoms of the actual problem. In order to discover the cause of the problem, it is necessary to consider the airport terminal as an integral part of much more complex regional, national or international transportation system. This article reflects the above mentioned requirements and introduces an innovative approach to passenger and baggage flow simulation based on the fact that airport terminal is considered as an integral part of air passenger door-to-door transportation process.
基金supported by the National Natural Science Foundation of China(12125505).
文摘The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance.
文摘导航系统依赖传感器感知周围环境。当前,基于单一传感器的导航系统已难以满足各类复杂场景下的导航需求,导航系统正朝传感器多源化方向发展。在多源传感器数据融合过程中,图像数据的处理最消耗时间和资源,对系统性能影响最大。为解决这些问题,设计智能导航平台的硬件控制终端,利用基于全球卫星导航系统(Global Navigation Satellite System,GNSS)秒脉冲(Pulse Per Second,PPS)的时间同步,实现多源传感器数据融合;设计用于同步定位与地图构建(Simultaneous Localization And Mapping,SLAM)前端ORB(Oriented FAST and Rotated BRIEF)特征提取加速器,加速图像处理过程,提高SLAM系统的实时性。实验结果表明,硬件平台不仅支持GNSS、惯性测量单元(Inertial Measurement Unit,IMU)、视觉和激光雷达的数据采集和融合,还能加速图像ORB特征点提取。在执行图像ORB特征提取任务时,与CPU和GPU平台上的实现相比,该加速器的帧率分别达到了它们的2.7倍和1.8倍,而功耗仅为它们的5.1%和2.9%。
