人群数量估计是人群管理系统的关键,对于预防踩踏事故和引导人群至关重要,已成为一个日益重要的任务和具有挑战性的研究方向。本文提出一种数据相关的拆分注意力机制的编码器-解码器结构的人群计数方法,称为DNe StCount。为应对视频监...人群数量估计是人群管理系统的关键,对于预防踩踏事故和引导人群至关重要,已成为一个日益重要的任务和具有挑战性的研究方向。本文提出一种数据相关的拆分注意力机制的编码器-解码器结构的人群计数方法,称为DNe StCount。为应对视频监控的尺度变化和透视失真的挑战,将更密集的空洞采样比率应用到密集空洞空间金字塔池化模块DASPP设计中。为提升密度图估计的准确性,将可学习的、数据相关的上采样方法 DUpsampling应用到特征聚合模块DFA设计中。为弥补欧几里德损失可能存在对离群值敏感、训练不稳定等缺点,采用Smooth L1损失设计损失函数。在具有挑战性的数据集上进行的实验和分析表明,本文提出的人群计数方法 DNe St Count与其他主流方法相比更具有竞争力。展开更多
We developed a novel absolute multi-pole encoder structure to improve the resolution of the multi-pole encoder, realize absolute output and reduce the manufacturing cost of the encoder. The structure includes two ring...We developed a novel absolute multi-pole encoder structure to improve the resolution of the multi-pole encoder, realize absolute output and reduce the manufacturing cost of the encoder. The structure includes two ring alnicos defined as index track and sub-division track, respectively. The index track is magnetized based on the improved gray code, with linear halls placed around the track evenly. The outputs of linear halls show the region the rotor belongs to. The sub-division track is magnetized to N-S-N-S (north-south-north-south), and the number of N-S pole pairs is determined by the index track. Three linear hall sensors with an air-gap of 2 mm are used to translate the magnetic filed to voltage signals. The relative offset in a single N-S is obtained through look-up. The magnetic encoder is calibrated using a higher-resolution incremental optical encoder. The pulse output from the optical encoder and hall signals from the magnetic encoder are sampled at the same time and transmitted to a computer, and the relation between them is calculated, and stored in the FLASH of MCU (micro controller unit) for look-up. In the working state, the absolute angle is derived by looking-up with hall signals. The structure is simple and the manufacturing cost is very low and suitable for mass production.展开更多
To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra...To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra-frame and inter-frame coding modes.The intra-frame coding is a rate-distortion optimized adaptive block size that can be also used for the compression of a single screen image.The inter-frame coding utilizes hierarchical group of pictures(GOP) structure to improve system performance during random accesses and fast-backward scans.Experimental results demonstrate that the proposed CABHG method has approximately 47%-48% higher compression ratio and 46%-53% lower CPU utilization than professional screen image sequence codecs such as TechSmith Ensharpen codec and Sorenson 3 codec.Compared with general video codecs such as H.264 codec,XviD MPEG-4 codec and Apple's Animation codec,CABHG also shows 87%-88% higher compression ratio and 64%-81% lower CPU utilization than these general video codecs.展开更多
文摘人群数量估计是人群管理系统的关键,对于预防踩踏事故和引导人群至关重要,已成为一个日益重要的任务和具有挑战性的研究方向。本文提出一种数据相关的拆分注意力机制的编码器-解码器结构的人群计数方法,称为DNe StCount。为应对视频监控的尺度变化和透视失真的挑战,将更密集的空洞采样比率应用到密集空洞空间金字塔池化模块DASPP设计中。为提升密度图估计的准确性,将可学习的、数据相关的上采样方法 DUpsampling应用到特征聚合模块DFA设计中。为弥补欧几里德损失可能存在对离群值敏感、训练不稳定等缺点,采用Smooth L1损失设计损失函数。在具有挑战性的数据集上进行的实验和分析表明,本文提出的人群计数方法 DNe St Count与其他主流方法相比更具有竞争力。
基金Funded partly by Heilongjiang Province Financial Fund for Researchers Returning from Abroad
文摘We developed a novel absolute multi-pole encoder structure to improve the resolution of the multi-pole encoder, realize absolute output and reduce the manufacturing cost of the encoder. The structure includes two ring alnicos defined as index track and sub-division track, respectively. The index track is magnetized based on the improved gray code, with linear halls placed around the track evenly. The outputs of linear halls show the region the rotor belongs to. The sub-division track is magnetized to N-S-N-S (north-south-north-south), and the number of N-S pole pairs is determined by the index track. Three linear hall sensors with an air-gap of 2 mm are used to translate the magnetic filed to voltage signals. The relative offset in a single N-S is obtained through look-up. The magnetic encoder is calibrated using a higher-resolution incremental optical encoder. The pulse output from the optical encoder and hall signals from the magnetic encoder are sampled at the same time and transmitted to a computer, and the relation between them is calculated, and stored in the FLASH of MCU (micro controller unit) for look-up. In the working state, the absolute angle is derived by looking-up with hall signals. The structure is simple and the manufacturing cost is very low and suitable for mass production.
基金Project(60873230) supported by the National Natural Science Foundation of China
文摘To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra-frame and inter-frame coding modes.The intra-frame coding is a rate-distortion optimized adaptive block size that can be also used for the compression of a single screen image.The inter-frame coding utilizes hierarchical group of pictures(GOP) structure to improve system performance during random accesses and fast-backward scans.Experimental results demonstrate that the proposed CABHG method has approximately 47%-48% higher compression ratio and 46%-53% lower CPU utilization than professional screen image sequence codecs such as TechSmith Ensharpen codec and Sorenson 3 codec.Compared with general video codecs such as H.264 codec,XviD MPEG-4 codec and Apple's Animation codec,CABHG also shows 87%-88% higher compression ratio and 64%-81% lower CPU utilization than these general video codecs.
