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Radiomics is a promising technology that focuses on improvements of image analysis, using an automated high-throughput extraction of quantitative features. However, the character of lesion is affected by the surrounding tissue. A lesion on…

Quantitative Methods · Quantitative Biology 2021-11-12 Takuma Usuzaki , Kengo Takahash , Kazuma Umemiya

To avoid decorrelation, conventional synthetic aperture radar interferometry (InSAR) requires that interferometric images should have a common spectral band and the same resolution after proper preprocessing. For a high-resolution (HR)…

Signal Processing · Electrical Eng. & Systems 2020-10-15 Huizhang Yang , Chengzhi Chen , Shengyao Chen , Feng Xi , Zhong Liu

Using kilometric arrays of air Cherenkov telescopes, intensity interferometry may increase the spatial resolution in optical astronomy by an order of magnitude, enabling images of rapidly rotating stars with structures in their…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Dainis Dravins , Stephan LeBohec , Hannes Jensen , Paul D. Nuñez

Although a lateral-shear interferometer is robust against optical component vibrations, its interferogram provides information about differential wavefronts rather than the wavefronts themselves, resulting in the loss of specific frequency…

This paper takes advantage of a recent method able to extract the characteristics of resonant modes in a metallic enclosure such as a reverberation chamber (RC). The aim here is to analyze, the effect of inserting curvilinear objects within…

Applied Physics · Physics 2026-05-06 François Sarrazin , Guillaume Andrieu

With the wave interferometric approach, we study how extrinsically multiple coherent waves excitation can dramatically alter the overall scattering states, resulting in tailoring the energy assignment among radiation and dissipation. To…

Diffusion models are proficient at generating high-quality images. They are however effective only when operating at the resolution used during training. Inference at a scaled resolution leads to repetitive patterns and structural…

Computer Vision and Pattern Recognition · Computer Science 2024-11-28 Haosen Yang , Adrian Bulat , Isma Hadji , Hai X. Pham , Xiatian Zhu , Georgios Tzimiropoulos , Brais Martinez

Interloper contamination due to line misidentification is an important issue in the future low-resolution spectroscopic surveys. We realize that the algorithm previously used for photometric redshift self-calibration, with minor…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-28 Hui Peng , Yu Yu

For each photon wave packet of extragalactic light, the dispersion by line-of-sight intergalactic plasma causes an increase in the envelope width and a chirp (drift) in the carrier frequency. It is shown that for continuous emission of many…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Richard Lieu , Lingze Duan

In this paper we analyze the effect of the calibration period, or lack of, on self-interference channel estimation in the digital domain of in-band full-duplex radio transceivers. In particular, we consider a scenario where the channel…

Information Theory · Computer Science 2014-09-05 Dani Korpi , Lauri Anttila , Mikko Valkama

The Integrated Sachs-Wolfe (ISW) effect is a large-angle modulation of the cosmic microwave background (CMB), generated when CMB photons traverse evolving potential wells associated with large scale structure (LSS). Recent efforts have been…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-02 Jessica Muir , Dragan Huterer

Interferometry can measure the shape or the material density of a system that could not be measured otherwise by recording the difference between the phase change of a signal and a reference phase. This difference is always between $-\pi$…

Plasma Physics · Physics 2022-10-20 Pierre-Alexandre Gourdain , Aidan Bachmann

Synthetic aperture laser radar has higher resolution, so requires higher modulated bandwidth. Because the data volume of chirp or pulse coding schemes is too large, it brings much pressure to data acquisition and data processing. So, we can…

Signal Processing · Electrical Eng. & Systems 2020-05-11 Fuping Fang , Heng Hu , Weiming Xu , Rong Shu

It is known that a spatially partially coherent light field produces better imaging contrast compared to a spatially coherent field and that the contrast increases as the spatial coherence length of the field becomes smaller. The transverse…

In radio astronomy, accurate calibration is of crucial importance for the new generation of radio interferometers. More specifically, because of the potential presence of outliers which affect the measured data, robustness needs to be…

Instrumentation and Methods for Astrophysics · Physics 2018-08-01 Virginie Ollier , Mohammed Nabil El Korso , André Ferrari , Rémy Boyer , Pascal Larzabal

The correction of the influence of phase corrugation in the pupil plane is a fundamental issue in achieving high dynamic range imaging. In this paper, we investigate an instrumental setup which consists in applying interferometric…

Astrophysics · Physics 2008-11-26 S. Lacour , E. Thiébaut , G. Perrin

Magnetic resonance imaging (MRI) is a widely used non-invasive imaging modality. However, a persistent challenge lies in balancing image quality with imaging speed. This trade-off is primarily constrained by k-space measurements, which…

Image and Video Processing · Electrical Eng. & Systems 2025-11-19 Guanxiong Luo , Shoujin Huang , Martin Uecker

We investigate the effects of atmospheric dispersion on observations of the Sun at the ever-higher spatial resolutions afforded by increased apertures and improved techniques. The problems induced by atmospheric refraction are particularly…

Astrophysics · Physics 2008-11-26 Kevin P. Reardon

Recovering images from optical interferometric observations is one of the major challenges in the field. Unlike the case of observations at radio wavelengths, in the optical the atmospheric turbulence changes the phases on a very short time…

The latest breakthroughs in time-varying photonics are fueling novel thermal emission phenomena, for example, showing that the dynamic amplification of quantum vacuum fluctuations, induced by the time-modulation of material properties,…