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关键词： Dissection   Aneurysms   Stroke  

关键词： Compression and extension triaxial test   Elastoplastic model   Matsuoka-Nakai criterion   Modified cam clay model   The intermediate principal stress effect  

摘要： The fundamental Cam-Clay constitutive model for soils did not include strength anisotropy in the deviatoric plane (i.e., Lode angle effects) through a modified failure criterion, so there was no difference in deviatoric stress between the compression and extension paths. However, the extension triaxial and true triaxial tests exhibit differences in shear resistance response compared to the compression path. This difference in shear stress response can impact numerical simulations because the stress paths can be uncertain throughout the domain of the simulated model. The paper presents three straightforward methods to incorporate Lode angle effects using the Matsuoka-Nakai criterion. Triaxial compression and extension tests under drained and undrained conditions were simulated. Several lessons were learned from these simulations about the ease of incorporating the Matsuoka-Nakai criterion and the differences between simulations using three methods. Finally, an extensive discussion focuses on identifying the most suitable alternative for simulating soil mechanical behavior. This discussion was intended as a simple improvement to the modified Cam Clay model for basic simulations or as a basis for further, more complex model development.

关键词： Voltage   Circuits   Systolic arrays   Integrated circuit reliability   Delays   Voltage control   System-on-chip   Memory management   Complexity theory   Clocks   Accelerators   CAD   energy efficiency   reduced voltage  

摘要： Since dynamic power has a quadratic relationship with voltage, reducing voltage is an effective way to lower power consumption in digital circuits. However, maintaining stable operation at lower voltages is challenging due to increased sensitivity to process, voltage, and temperature (PVT) variations, making it difficult to determine optimal operating points using static timing analysis (STA). While circuit- and device-level solutions like timing error detection (TED) systems can enable lower voltage operation, they introduce significant overhead and design complexity. In this article, we integrate an algorithm-based fault tolerance (ABFT) method into the structure of systolic arrays (SAs) to capture timing errors when voltage is scaled down, ensuring safe and optimized low-voltage operation. Our proposed approach, SCISSORS, demonstrates how extra voltage margins in SAs used for matrix arithmetic can be trimmed by integrating a simple algorithmic technique into the structure of the array. This solution not only detects errors in the accelerator but also those caused by voltage reduction in on-chip memory and auxiliary circuits. It is fully implementable through hardware description languages (HDL) without requiring transistor- or circuit-level modifications to the netlist. Implementation on a Zynq system-on-chip (SoC) shows that SCISSORS introduces only a tolerable overhead of 11% and 8% for 32x32 and 64x64 SAs, respectively, while achieving nearly a 2x improvement in energy efficiency. Experimental results further demonstrate that SCISSORS adaptively adjusts voltage in response to the voltage-temperature coupling behavior of digital circuits at runtime, specifically addressing inverse temperature dependence (ITD).

关键词： Image reconstruction   Detectors   Computed tomography   Imaging   Digital TV   X-ray imaging   Solid modeling   Total variance   Reconstruction algorithms   Design automation   Chambolle-Pock (CP)   computer aided design (CAD)   directional total variation (DTV)   optimization   orthogonal translation (OT) computed laminography  

摘要： The orthogonal translation (OT) computed laminography (OTCL) is suitable for 3-D high-resolution imaging of plates. However, the projection data via OT scanning is in fact limited-angle data, which will produce inter-layer aliasing artifacts in the reconstructed image. Inspired by the success of the directional total variation (DTV) algorithm in 2-D limited-angle computed tomography (CT), in this work, we propose a computer aided design (CAD) image guided DTV (CDTV) algorithm. The CDTV model is a constrained optimization model. The constraint terms are the CDTV term and DTV term, whereas the objective term is the data fidelity term. We solve this model by the use of the Chambolle-Pock (CP) algorithm. To evaluate this newly-proposed algorithm, we perform the simulation experiments and a real data experiment. The filtered back projection (FBP), simultaneous algebra reconstruction technique (SART), total variation (TV), truncated adaptive-weight TV (TAwTV), CAD prior image guided adaptive weighted high-order total variation (Cpi-awHOTV) and DTV algorithms are selected as comparison versions. Both the simulation and the real data experiments show that the CDTV algorithm can effectively suppress the aliasing artifacts and improve the layer-to-layer quality of the reconstructed images. The code for this article is publicly available at the following website: https://***/YaruiXi/CDTV-algorithm

关键词： automatic tooth segmentation   CAD/CAM software   digital models  

摘要： Objective: To investigate and compare the accuracy of the automatic orthodontic tooth segmentation process performed by three commercial CAD software packages. Materials and Methods: Three typodonts, representing different degrees of crowding in both arches (mild, moderate and severe), were scanned and the files imported into three professional CAD software packages (ArchForm, OrthoSystem and VISION). In addition, 28 removable teeth, used for construction of each typodont, were scanned and their STL. files used for reference purposes. After tooth segmentation, the STL. file generated for each tooth by each software was 3D-superimposed onto its reference, and measurements were analyzed for each tooth subgroup in both arches. Both 2D discrepancies at 13 different points (mm) and central mesiodistal width (mm), and 3D discrepancies in area and volume (mm3) were investigated. Tooth segmentation accuracy was compared with respect to the reference STL. files and among software packages. The amount of crowding was investigated for its influence on the tooth segmentation process. Results: Most linear and 3D measurements displayed some degree of inaccuracy, with a general tendency to oversize segmented teeth. The degree of crowding did not appear to affect the accuracy of tooth segmentation, considering both arches and each individual tooth group (p > 0.05). Different software packages performed differently, though likely not to a clinically significant degree for most of the discrepancies found. In particular, OrthoSystem and VISION demonstrated better accuracy compared to ArchForm. Conclusions: Automatic tooth segmentation software presents variable degrees of inaccuracy, irrespective of crowding severity. The different software packages evaluated demonstrated varying levels of accuracy, with no clinically significant differences among them, except in a few cases. While most single-point discrepancies can be considered clinically irrelevant (< 0.1 mm), exceptions include t

关键词： gravitational lensing: weak   cosmological parameters   large-scale structure  

摘要： We present the first application of marked power spectra to weak lensing data, using maps from the Subaru Hyper Suprime-Cam Year 1 (HSC-Y1) survey. Marked convergence fields, constructed by weighting the convergence field with non-linear functions of its smoothed version, are designed to encode higher-order information while remaining computationally tractable. Using simulations tailored to the HSC-Y1 data, we test three mark functions that up- or down-weight different density environments. Our results show that combining multiple types of marked auto and cross-spectra improves constraints on the clustering amplitude parameter $S_8\equiv \sigma _8\sqrt{\Omega _{\rm m}/0.3}$ by $\approx$43 per cent compared to standard two-point power spectra. When applied to the HSC-Y1 data, this translates into a constraint on $S_8 = 0.807\pm 0.024$. We assess the sensitivity of the marked power spectra to systematics, including baryonic effects, intrinsic alignment, photometric redshifts, and multiplicative shear bias. We note that some of the additional information introduced by the marked field originates from scales smaller than the scale cut, and is partly Gaussian in nature. This does not invalidate our systematic tests. These results demonstrate the promise of marked statistics as a practical and powerful tool for extracting non-Gaussian information from weak lensing surveys.

关键词： breast lesions   classification   deep learning   dynamic tissue stimulation   grading   RFTSDP Method   ultrasound RF time series  

摘要： Objectives Accurate detection of breast lesion type is crucial for optimizing treatment;however, due to the limited precision of current diagnostic methods, biopsies are often required. To address this limitation, we proposed radio frequency time series dynamic processing (RFTSDP) in 2020, which analyzes the dynamic response of tissue and the impact of scatterer displacement on RF echoes during controlled stimulations to enhance diagnostic information. Methods We developed a vibration-generating device and collected ultrafast ultrasound data from 11 ex vivo breast tissue samples under different stimulations. Deep learning (DL) was used for automated feature extraction and lesion classification into 2, 3, and 5 categories. The performance of the convolutional neural network (CNN)-based RFTSDP method was compared with traditional machine learning techniques, which involved spectral and nonlinear feature extraction from RF time series, followed by a support vector machine (SVM). Results With 65 Hz vibration, the DL-based RFTSDP method achieved 99.53 +/- 0.47% accuracy in classifying and grading breast lesions. CNN consistently outperformed SVM, particularly under vibratory stimulation. In 5-class classification, CNN reached 98.01% versus 95.64% for SVM, with the difference being statistically significant (P < .05). Furthermore, the CNN-based RFTSDP method showed a 28.67% improvement in classification accuracy compared to the non-stimulation condition and the analysis of focused raw data. Conclusions We developed a DL-based CAD system capable of classifying and grading breast lesions. This study demonstrates that the proposed system not only enhances classification but also ensures increased stability and robustness compared to traditional methods.

关键词： Aspirin   Hazard ratio   Hemorrhage   Medical risk factors   Myocardial infarction   Percutaneous coronary intervention   Randomized trials   Secondary prevention   Stable coronary artery disease  

摘要： AbstractClinical Impact RatingsGIM/FP/GP: Cardiology:

关键词： Complementary FeFETs   logic-in-memory   CAM   hamming distance   few-shot learning   XOR   Complementary FeFETs   logic-in-memory   CAM   hamming distance   few-shot learning   XOR  

摘要： Classification-based learning in deep neural networks, particularly few-shot learning, demands efficient similarity metrics such as Hamming distance. Conventional architectures suffer from high energy overheads due to frequent data movement between memory and processing units, hindering scalability. In-memory computing addresses this by integrating computation within memory, yet analog-based systems rely on power-hungry analog-to-digital converters (ADCs) and face scalability challenges due to device variability, especially in emerging memories. This work presents a fully digital Ferroelectric FET (FeFET)-based Logic-in-Memory (LiM) XOR cell, designed using GlobalFoundries' 28 nm technology, eliminating ADCs and ensuring robust, energy-efficient, and scalable operation. Our 2T FeFET XOR cell, applied to 4096-bit Hamming distance calculations, achieves 23 x lower energy, 3x faster latency, and 14 x area reduction over state-of-the-art designs. Delivering 2337 Gsamples/(s & sdot;W & sdot;mm(2)) - a 300x improvement - this architecture offers a compelling solution for energy-efficient, reliable, and scalable AI hardware, driving sustainable computing.

关键词： Arterial dissection   Migraine   Stroke