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Tomographic imaging systems are expected to work with a wide range of samples that house complex structures and challenging material compositions, which can influence image quality in a bad way. Complex samples increase total measurement…

Robotics · Computer Science 2023-06-27 Erdal Pekel , María Lancho Lavilla , Franz Pfeiffer , Tobias Lasser

In the last decade C-arm-based cone-beam CT became a widely used modality for intraoperative imaging. Typically a C-arm scan is performed using a circle-like trajectory around a region of interest. Therefor an angular range of at least…

Medical Physics · Physics 2015-06-11 Ludwig Ritschl , Jan Kuntz , Marc Kachelrieß

For the accurate representation and reconstruction of band-limited signals on the sphere, an optimal-dimensionality sampling scheme has been recently proposed which requires the optimal number of samples equal to the number of degrees of…

Information Theory · Computer Science 2017-09-11 Wajeeha Nafees , Zubair Khalid , Rodney A. Kennedy , Jason D. McEwen

In this paper, we propose a novel optimization-based trajectory planner that utilizes spherical harmonics to estimate the collision-free solution space around an agent. The space is estimated using a constrained over-determined…

Robotics · Computer Science 2021-07-16 Steven Patrick , Efstathios Bakolas

Robotic ultrasound (US) imaging aims at overcoming some of the limitations of free-hand US examinations, e.g. difficulty in guaranteeing intra- and inter-operator repeatability. However, due to anatomical and physiological variations…

Robotics · Computer Science 2022-08-11 Zhongliang Jiang , Yuan Gao , Le Xie , Nassir Navab

We develop a sampling scheme on the sphere that permits accurate computation of the spherical harmonic transform and its inverse for signals band-limited at $L$ using only $L^2$ samples. We obtain the optimal number of samples given by the…

Information Theory · Computer Science 2014-07-25 Zubair Khalid , Rodney A. Kennedy , Jason D. McEwen

We present a flyscan compatible acquisition scheme for three-modal X-Ray Computed Tomography (CT) with two-dimensional phase sensitivity. Our approach is demonstrated using a "beam tracking" setup, through which a sample's attenuation,…

Medical Physics · Physics 2022-08-26 G. Lioliou , O. Roche i Morgó , S. Marathe , K. Wanelik , S. Cipiccia , A. Olivo , C. K. Hagen

Higher spatial resolution and larger imaging scene are always the goals pursued by advanced space-borne SAR system.High resolution and wide swath SAR imaging can provide more information about the illuminated scene of interest on one…

Signal Processing · Electrical Eng. & Systems 2024-02-27 Xinhua Mao

Recent work by McClarren & Hauck [29] suggests that the filtered spherical harmonics method represents an efficient, robust, and accurate method for radiation transport, at least in the two-dimensional (2D) case. We extend their work to the…

High Energy Astrophysical Phenomena · Physics 2013-04-16 David Radice , Ernazar Abdikamalov , Luciano Rezzolla , Christian D. Ott

In practice, the finite number of samples of the spherical radiation pattern or antenna gain are taken on the sphere for both the reconstruction of the antenna radiation pattern and the computation of mobile handset performance measures…

Signal Processing · Electrical Eng. & Systems 2018-12-03 Umair Ahmed , Zubair Khalid

We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in-situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source…

3D reconstruction plays an increasingly important role in modern photogrammetric systems. Conventional satellite or aerial-based remote sensing (RS) platforms can provide the necessary data sources for the 3D reconstruction of large-scale…

Computer Vision and Pattern Recognition · Computer Science 2023-05-19 San Jiang , Yaxin Li , Duojie Weng , Kan You , Wu Chen

This paper focuses on minimizing the time requirement for CT capture through innovative simultaneous x-ray capture method. The state-of-the-art CT imaging methodology captures a sequence of projections during which the internal organ…

Medical Physics · Physics 2014-04-03 Sajib Saha , Murat Tahtali , Andrew Lambert , Mark Pickering

Diagnostic stroke imaging with C-arm cone-beam computed tomography (CBCT) enables reduction of time-to-therapy for endovascular procedures. However, the prolonged acquisition time compared to helical CT increases the likelihood of rigid…

Image and Video Processing · Electrical Eng. & Systems 2019-12-02 Alexander Preuhs , Michael Manhart , Philipp Roser , Bernhard Stimpel , Christopher Syben , Marios Psychogios , Markus Kowarschik , Andreas Maier

This work presents an efficient method to solve a class of continuous-time, continuous-space stochastic optimal control problems of robot motion in a cluttered environment. The method builds upon a path integral representation of the…

Systems and Control · Computer Science 2016-03-10 Jung-Su Ha , Han-Lim Choi

Image-guided navigation of catheter devices to anatomic targets within large 3D cardiac chambers and vessels is challenging in the interventional setting due to the limitations of a conventional 2D x-ray projection format. Scanning-beam…

Medical Physics · Physics 2024-03-26 Jordan M. Slagowski

Due to the current lack of large-scale datasets at the million-scale level, tasks involving panoramic images predominantly rely on existing two-dimensional pre-trained image benchmark models as backbone networks. However, these networks are…

Computer Vision and Pattern Recognition · Computer Science 2025-07-15 Jingguo Liu , Han Yu , Shigang Li , Jianfeng Li

The use of random sampling in decision-making and control has become popular with the ease of access to graphic processing units that can generate and calculate multiple random trajectories for real-time robotic applications. In contrast to…

Robotics · Computer Science 2022-03-21 Hyung-Jin Yoon , Chuyuan Tao , Hunmin Kim , Naira Hovakimyan , Petros Voulgaris

This paper presents a new trajectory replanner for grasping irregular objects. Unlike conventional grasping tasks where the object's geometry is assumed simple, we aim to achieve a "dynamic grasp" of the irregular objects, which requires…

Robotics · Computer Science 2025-01-31 Minh Nhat Vu , Florian Grander , Anh Nguyen

In 3D single particle imaging with X-ray free-electron lasers, particle orientation is not recorded during measurement but is instead recovered as a necessary step in the reconstruction of a 3D image from the diffraction data. Here we use…

Data Analysis, Statistics and Probability · Physics 2016-05-25 Julien Flamant , Nicolas Le Bihan , Andrew V. Martin , Jonathan H. Manton
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