arXiv subjects

Haiyan Yao

Publications and source records attributed to Haiyan Yao.

3 recordsLinked to original sources

arXiv2026

Particle swarm optimization fitting of long-range wake potentials for trapped-mode parameter characterization in the HALF storage ring

Accurate extraction of trapped-mode impedance parameters of complex storage ring components is essential for assessing their impact on coupled-bunch instabilities. This paper proposes a parameter extraction method based on particle swarm optimization. By constructing a multi-resonator fitting model, trapped-mode parameters are extracted from partially decayed long-range wake potentials. Benchmark validation using a cylindrical pillbox cavity demonstrates that the proposed method yields results consistent with those obtained from the CST eigenmode solver and the existing differential evolution method for both longitudinal and transverse cases, while significantly reducing the computational cost. The method is further applied to three critical components of the Hefei Advanced Light Facility storage ring, demonstrating its applicability to complex structures.

physics.acc-ph↗

arXiv2017

Deep Spatial Regression Model for Image Crowd Counting

Computer vision techniques have been used to produce accurate and generic crowd count estimators in recent years. Due to severe occlusions, appearance variations, perspective distortions and illumination conditions, crowd counting is a very challenging task. To this end, we propose a deep spatial regression model(DSRM) for counting the number of individuals present in a still image with arbitrary perspective and arbitrary resolution. Our proposed model is based on Convolutional Neural Network (CNN) and long short term memory (LSTM). First, we put the images into a pretrained CNN to extract a set of high-level features. Then the features in adjacent regions are used to regress the local counts with a LSTM structure which takes the spatial information into consideration. The final global count is obtained by a sum of the local patches. We apply our framework on several challenging crowd counting datasets, and the experiment results illustrate that our method on the crowd counting and density estimation problem outperforms state-of-the-art methods in terms of reliability and effectiveness.

cs.CV↗

arXiv2017

Image Crowd Counting Using Convolutional Neural Network and Markov Random Field

In this paper, we propose a method called Convolutional Neural Network-Markov Random Field (CNN-MRF) to estimate the crowd count in a still image. We first divide the dense crowd visible image into overlapping patches and then use a deep convolutional neural network to extract features from each patch image, followed by a fully connected neural network to regress the local patch crowd count. Since the local patches have overlapping portions, the crowd count of the adjacent patches has a high correlation. We use this correlation and the Markov random field to smooth the counting results of the local patches. Experiments show that our approach significantly outperforms the state-of-the-art methods on UCF and Shanghaitech crowd counting datasets.

cs.CV↗