Abstract Objective. To determine the minimum detector width along fan-angle direction in offset-detector cone-beam breast CT for multiple advanced reconstruction algorithms and to investigate effect on radiation dose, scatter, image quality. Approach. Complete sinograms (m × n = 1024 768 pixels) of 30 clinical datasets previously acquired a clinical-prototype system were reconstructed using Feldkamp-Davis-Kress (FDK) algorithm served as reference. retrospectively truncated varying widths...

Abstract The feasibility of full-scan, offset-detector geometry cone-beam CT has been demonstrated for several clinical applications. For full-scan acquisition with geometry, data redundancy from complementary views can be exploited during image reconstruction. Envisioning an upright breast system, we propose to acquire short-scan in conjunction geometry. To tackle the resulting incomplete data, have developed a self-supervised attenuation field network (AFN). AFN leverages inherent through...

Purpose To design a pulse sequence for efficient 3D T2‐weighted imaging and T2 mapping. Methods A stack‐of‐stars turbo spin echo with variable refocusing flip angles flexible pseudorandom view ordering is proposed simultaneous An analytical framework introduced the selection of to maximize relative tissue contrast while minimizing estimation errors maintaining low specific absorption rate. Images at different times are generated using subspace constrained iterative reconstruction algorithm....

Abstract To develop and investigate a deep learning approach that uses sparse-view acquisition in dedicated breast computed tomography for radiation dose reduction, we propose framework combines 3D cone-beam with multi-slice residual dense network (MS-RDN) reconstruction. Projection datasets (300 views, full-scan) from 34 women were reconstructed using the FDK algorithm served as reference. Sparse-view (100 projection data algorithm. The proposed MS-RDN reference reconstructions input label,...

摘要: 提出一种新型可变形轮腿式地面移动机器人,采用相同动力源实现轮式和腿式两种移动模式。将Chebyshev机构与平行四边形机构结合,提出了具有两种单自由度运动形式的单环闭链2RP3R变胞机构,进行了构型设计和运动学分析。将2个单环闭链变胞机构构造成轮腿式移动模块,进而构建一种可变形轮腿式机器人。机器人具有256种运动形式,这些运动形式均采用相同的动力源,实现多足切换,通过不同高度的空间,在曲柄与机架共线时进行移动模式切换,实现倾倒后恢复。然后,分析了机器人的移动性能,得到腿式模式下的平均越障能力和两种模式下的平均速度比。建立虚拟样机模型,完成了机器人平地行走、越障、转向和模式切换仿真试验。研制一台样机,进行了两种模式下的移动试验,验证了机器人方案的可行性。

Purpose In radial abdominal imaging, it has been commonly observed that signal from the arms cause streaks due to system imperfections. We previously introduced a streak removal technique (B‐STAR), which is inherently spatially variant and limited work in image space. this work, we propose invariant cancellation (CACTUS), can be applied either space or k‐space compatible with iterative reconstructions. Theory Methods Streak sources are typically localized represented using low‐dimensional...

We aim to determine the combination of X-ray spectrum and detector scintillator thickness that maximizes detectability microcalcification clusters in dedicated cone-beam breast CT.

Person-following is a crucial capability for service robots, and the employment of vision technology leading trend in building environmental understanding. While most existing methodologies rely on tracking-by-detection strategy, which necessitates extensive datasets training yet remains susceptible to noise, we propose novel approach: real-time tracking-by-segmentation with future motion estimation framework. This framework facilitates pixel-level tracking target individual predicts their...

Summary Removing source wavelet and residual non-uniform absorption (Q) effects can enhance the spatial resolution of seismic images after de-ghosting amplitude attenuation compensation. In this abstract we propose a new enhancement method that incorporates structural conformity constraints sparse regularization into an inversion-based deconvolution. The was applied to field data compared with approach without constraints. provides resolution-enhanced broader bandwidth image improved...

Recently, deep learning models have been developed for reconstructing data acquired using radial turbo spin echo sequences, yielding images at multiple times as well co-registered T2 maps. In imaging, streaking artifacts from anatomical regions where the magnetic field gradients are nonlinear can obscure pathology and impact accuracy of parameter mapping. this work, we demonstrate that removal prior to training provide substantial improvement in reconstruction performance methods.

This study presents a deep learning based technique for slice super resolution in RADTSE T2 mapping. The proposed method may be used to accelerate full liver imaging, while maintaining sufficient through-plane detection of small pathologies.

Radial trajectories are appealing for efficient parameter mapping due to their robustness undersampling compared Cartesian trajectories. However, streaks scanner imperfections can significantly affect image quality and accuracy of maps. Previously, we developed a streak reduction technique named CACTUS. CACTUS was demonstrated in cross-sectional (axial) abdominal imaging. The other two imaging planes (coronal sagittal) radial MRI more vulnerable these anomaly streaks. In this work,...

Radial imaging is appealing for quantitative parameter mapping, due to their inherently robustness undersampling compared Cartesian trajectories and thus, its ability yield maps with high spatial resolution from highly undersampled data. Two-dimensional radial typically acquires equiangular spaced lines, resulting in a circular field-of-view (FOV). Circular FOVs are not ideal applications an anisotropic region-of-support (e.g., spine, leg). Larson et al. proposed algorithm designing fully...

Dedicated cone-beam breast computed tomography (CBBCT) is an emerging modality and provides fully three-dimensional (3D) images of the uncompressed at isotropic voxel resolution. In effort to translate this cancer screening, advanced image reconstruction methods are being pursued. Since radiographic density established risk factor for CBBCT volumetric data, study investigates reproducibility glandular fraction (VGF), defined as proportion fibroglandular tissue volume relative total excluding...