X-ray tri-axial stress analysis system using two monolithic SOI pixel detectors

Anomaly Detection in Rails Using Dimensionality Reduction

“…Shingo MITSUI, 1) * Toshihiko SASAKI, 2) Masayoshi SHINYA, 3) Yasuo ARAI 4) and Ryutaro NISHIMURA 5) 1) Data Science and AI Innovation Research Promotion Center, Shiga University, 1-1-1 Banba, Hikone, Shiga, 522-8522 Japan.…”

“…reported the mechanism of rolling contact fatigue of rails by conducting triaxial stress analysis of rails using residual stresses and the full width at half maximum (FWHM) of the diffraction rings of X-rays. 1) Many systematic studies have been conducted on rail damage, such as residual stress, [2][3][4][5] crack propagation, 6,7) and white etching layer (WEL). [8][9][10][11][12] However, the details of the damage mechanism of rails have not been clarified because of the complex combination of multiple conditions, such as passing tonnage, transit speed, and weather conditions.…”

“…13) This reduced measurement time facilitates research using a large amount of measurement data, such as mapping measurements. Further applied studies have been conducted using the developed equipment: Sasaki et al reported triaxial stress analysis of rails, 1) and Nishimura et al reported precise measurements using synchrotron radiation. 19) In the cosα method, an X-ray beam is incident on a polycrystalline metal in one direction, and the diffraction ring formed by the diffracted X-rays according to Bragg's law is measured using a two-dimensional X-ray detector.…”

“…(3) and ( 4), respectively. Additionally, S is defined as follows: The data matrix  X , with the origin adjusted such that the sample mean is zero, can be expressed using X ≡ [x (1) ,..., x (N) ] as follows:…”

Proton radiation damage tolerance of wide dynamic range SOI pixel detectors

“…XRPIX has been developed for space X-ray observations, 1 SOFIST has been developed for high energy physics experiments, 2 and INTPIX has been developed for general use in ground experiments, such as stress measurement. 3 XRPIX achieves a high time resolution of about ∼ 10 µs by installing a trigger function to pixels. For this reason, the pixel size of XRPIX is quite large at 36 µm.…”