Searcharxiv⌕ Search

arXiv subjects

Peilin Li

Publications and source records attributed to Peilin Li.

25 records · Page 2Linked to original sources

Simulation of charge transport at the surface of planar silicon sensors

Radiation-hard silicon sensors used in high-energy physics require a high electric field and are susceptible to surface breakdown. This study aims to improve the understanding of the underlying mechanisms by developing new methods to probe the electric field at surface near the sensor's edge. For planar sensors, avalanche breakdown primarily occurs at the Si-SiO2 interface, where localized electric field peaks can form between the guard ring and the edge. Accurate simulations are challenging and it is essential to validate simulation parameters by comparing the simulation results to measurements. In this work, the electrical behavior of the edge region of planar silicon diodes was simulated using Synopsis TCAD. Transient Current Technique (TCT) simulations were performed in both TCAD and Allpix Squared, and compared to measurements. Additionally, laser scans over the edge region were performed in Allpix Squared to evaluate the simulated surface electric field and charge collection efficiency.

physics.ins-det↗

CDFormer: Cross-Domain Few-Shot Object Detection Transformer Against Feature Confusion

Cross-domain few-shot object detection (CD-FSOD) aims to detect novel objects across different domains with limited class instances. Feature confusion, including object-background confusion and object-object confusion, presents significant challenges in both cross-domain and few-shot settings. In this work, we introduce CDFormer, a cross-domain few-shot object detection transformer against feature confusion, to address these challenges. The method specifically tackles feature confusion through two key modules: object-background distinguishing (OBD) and object-object distinguishing (OOD). The OBD module leverages a learnable background token to differentiate between objects and background, while the OOD module enhances the distinction between objects of different classes. Experimental results demonstrate that CDFormer outperforms previous state-of-the-art approaches, achieving 12.9% mAP, 11.0% mAP, and 10.4% mAP improvements under the 1/5/10 shot settings, respectively, when fine-tuned.

cs.CV↗

TCAD Simulations of Humidity-Induced Breakdown of Silicon Sensors

The breakdown voltage of silicon sensors is known to be affected by the ambient humidity. To understand the sensor's humidity sensitivity, Synopsys TCAD was used to simulate n-in-p sensors for different effective relative humidities. Photon emission of hot electrons was imaged with a microscope to locate breakdown in the edge-region of the sensor. The Top-Transient Current Technique was used to measure charge transport near the surface in the breakdown region of the sensor. Using the measurements and simulations, the evolution of the electric field with relative humidity and the carrier densities towards breakdown in the periphery of p-bulk silicon sensors are investigated.

physics.ins-det↗

Building monomial ideals with fixed betti numbers

Motivated by the fact that as the number of generators of an ideal grows so does the complexity of calculating relations among the generators, this paper identifies collections of monomial ideals with a growing number of generators which have predictable free resolutions. We use elementary collapses from discrete homotopy theory to construct infinitely many monomial ideals, with an arbitrary number of generators, which have similar or the same betti numbers. We show that the Cohen-Macaulay property in each unmixed (pure) component of the ideal is preserved as the ideal is expanded.

math.AC↗

HPPNet: Modeling the Harmonic Structure and Pitch Invariance in Piano Transcription

While neural network models are making significant progress in piano transcription, they are becoming more resource-consuming due to requiring larger model size and more computing power. In this paper, we attempt to apply more prior about piano to reduce model size and improve the transcription performance. The sound of a piano note contains various overtones, and the pitch of a key does not change over time. To make full use of such latent information, we propose HPPNet that using the Harmonic Dilated Convolution to capture the harmonic structures and the Frequency Grouped Recurrent Neural Network to model the pitch-invariance over time. Experimental results on the MAESTRO dataset show that our piano transcription system achieves state-of-the-art performance both in frame and note scores (frame F1 93.15%, note F1 97.18%). Moreover, the model size is much smaller than the previous state-of-the-art deep learning models.

cs.SD↗

HarmoF0: Logarithmic Scale Dilated Convolution For Pitch Estimation

Sounds, especially music, contain various harmonic components scattered in the frequency dimension. It is difficult for normal convolutional neural networks to observe these overtones. This paper introduces a multiple rates dilated causal convolution (MRDC-Conv) method to capture the harmonic structure in logarithmic scale spectrograms efficiently. The harmonic is helpful for pitch estimation, which is important for many sound processing applications. We propose HarmoF0, a fully convolutional network, to evaluate the MRDC-Conv and other dilated convolutions in pitch estimation. The results show that this model outperforms the DeepF0, yields state-of-the-art performance in three datasets, and simultaneously reduces more than 90% parameters. We also find that it has stronger noise resistance and fewer octave errors. The code and pre-trained model are available at https://github.com/WX-Wei/HarmoF0.

cs.SD↗

Voltammetry at porous electrodes: A theoretical study

Theory is presented to simulate both chronoamperometry and cyclic voltammetry at porous electrodes fabricated by means of electro-deposition around spherical templates. A theoretical method to extract heterogeneous rate constants for quasireversible and irreversible systems is proposed by the approximation of decoupling of the diffusion within the porous electrode and of bulk diffusion to the electrode surface.

physics.chem-ph↗