5,840 research outputs found
Physics of neutrino flavor transformation through matter-neutrino resonances
In astrophysical environments such as core-collapse supernovae and neutron
star-neutron star or neutron star-black hole mergers where dense neutrino media
are present, matter-neutrino resonances (MNRs) can occur when the neutrino
propagation potentials due to neutrino-electron and neutrino-neutrino forward
scattering nearly cancel each other. We show that neutrino flavor
transformation through MNRs can be explained by multiple adiabatic solutions
similar to the Mikheyev-Smirnov-Wolfenstein mechanism. We find that for the
normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be
sensitive to the shape of neutrino spectra and the adiabaticity of the system,
but such sensitivity is absent for the inverted hierarchy.Comment: 7 pages, 4 figure
Privacy Protection Performance of De-identified Face Images with and without Background
Li Meng, 'Privacy Protection Performance of De-identified Face Images with and without Background', paper presented at the 39th International Information and Communication Technology (ICT) Convention. Grand Hotel Adriatic Congress Centre and Admiral Hotel, Opatija, Croatia, May 30 - June 3, 2016.This paper presents an approach to blending a de-identified face region with its original background, for the purpose of completing the process of face de-identification. The re-identification risk of the de-identified FERET face images has been evaluated for the k-Diff-furthest face de-identification method, using several face recognition benchmark methods including PCA, LBP, HOG and LPQ. The experimental results show that the k-Diff-furthest face de-identification delivers high privacy protection within the face region while blending the de-identified face region with its original background may significantly increases the re-identification risk, indicating that de-identification must also be applied to image areas beyond the face region
Hypothesis testing for medical imaging analysis via the smooth Euler characteristic transform
Shape-valued data are of interest in applied sciences, particularly in
medical imaging. In this paper, inspired by a specific medical imaging example,
we introduce a hypothesis testing method via the smooth Euler characteristic
transform to detect significant differences among collections of shapes. Our
proposed method has a solid mathematical foundation and is computationally
efficient. Through simulation studies, we illustrate the performance of our
proposed method. We apply our method to images of lung cancer tumors from the
National Lung Screening Trial database, comparing its performance to a
state-of-the-art machine learning model
Sub-daily simulation of mountain flood processes based on the modified soil water assessment tool (SWAT) model
Floods not only provide a large amount of water resources, but they also cause serious disasters. Although there have been numerous hydrological studies on flood processes, most of these investigations were based on rainfall-type floods in plain areas. Few studies have examined high temporal resolution snowmelt floods in high-altitude mountainous areas. The Soil Water Assessment Tool (SWAT) model is a typical semi-distributed, hydrological model widely used in runoff and water quality simulations. The degree-day factor method used in SWAT utilizes only the average daily temperature as the criterion of snow melting and ignores the influence of accumulated temperature. Therefore, the influence of accumulated temperature on snowmelt was added by increasing the discriminating conditions of rain and snow, making that more suitable for the simulation of snowmelt processes in high-altitude mountainous areas. On the basis of the daily scale, the simulation of the flood process was modeled on an hourly scale. This research compared the results before and after the modification and revealed that the peak error decreased by 77% and the time error was reduced from +/- 11 h to +/- 1 h. This study provides an important reference for flood simulation and forecasting in mountainous areas
- …