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关键词： developable surface segmentation   CAD models   sparse normal discontinuity   dihedral angle  

摘要： Segmenting CAD models into developable surface patches is a fundamental problem in geometric modeling and manufacturing-oriented applications. Existing approaches often rely on discrete Gaussian curvature estimation or Gauss map analysis;however, their performance on CAD meshes is frequently hindered by numerical instability, sensitivity to mesh tessellation, and complex parameter tuning. In this work, we propose a simple and robust method for developable surface segmentation based on a sparse normal discontinuity prior. Our key observation is that industrial CAD models are typically composed of large developable regions separated by a sparse set of sharp creases and edges. Consequently, segmentation boundaries correspond to sparse discontinuities in the surface normal field rather than continuous variations in curvature. Based on this perspective, we formulate developable surface segmentation as the detection of sparse normal jump discontinuities. In the discrete setting of triangle meshes, this formulation naturally leads to a dihedral angle-based approach that avoids explicit curvature estimation and admits an efficient graph-based solution. The proposed algorithm consists of face normal computation, dihedral angle-based boundary detection, and connected component extraction on a thresholded face adjacency graph. The method requires only a single geometrically interpretable parameter and naturally aligns segmentation boundaries with sharp features commonly found in CAD models. Experimental results on a diverse set of industrial CAD meshes, including standard benchmarks widely used in related research, demonstrate that the proposed approach achieves robust and accurate segmentation, as validated by both visual coherence and quantitative developability metrics.

关键词： Delays   FeFETs   Nonvolatile memory   Computer architecture   Time-domain analysis   Energy efficiency   Microprocessors   Computational modeling   Switches   In-memory computing   Ferroelectric FET (FeFET)   in-memory computing   time-domain   nonvolatile memory   content addressable memory   multiply-and-accumulate (MAC)  

摘要： Time-domain nonvolatile in-memory computing (TD-nvIMC) offers a promising pathway to reduce data movement and improve energy efficiency by encoding computation in delay rather than voltage or current. This work presents a fully integrated and reconfigurable TD-nvIMC macro, fabricated in 28 nm CMOS, that combines a ferroelectric FET (FeFET)-based content-addressable memory array, a cascaded delay element chain, and a time-to-digital converter. The architecture supports binary multiply-and-accumulate (MAC) operations using XORand AND-based matching, as well as in-memory Boolean logic and arithmetic functions. Sub-nanosecond MAC resolution is achieved through experimentally demonstrated 550 ps delay steps, representing a 2000 & times;improvement over prior FeFET TD-nvIMC work, enabled by multilevel-state calibration with <= 100 ps resolution. Write-disturb resilience is ensured via isolated triple-well bulks. The proposed macro achieves a measured throughput of 222.2 MOPS/cell and energy efficiency of 1887 TOPS/W at 0.85 V, establishing a viable path toward scalable, energy-efficient TD-nvIMC accelerators.

关键词： Ceramic discs   Try-in pastes   CIEDE2000   Translucency   Bleach shades   CAD/CAM ceramics   Spectrophotometer   Color thresholds  

摘要： Background This study evaluated the optical influence of try-in media (distilled water, glycerin, and commercial try-in pastes) on ultrathin (0.5-mm) CAD/CAM bleach-shade ceramic discs, focusing on CIEDE2000 color difference (Delta E-00), translucency parameter (TP00;Delta E-00 between white- and black-backed measurements), and device-reported shade outputs across different ceramic systems. Methods Forty-four 0.5-mm CAD/CAM ceramic discs were fabricated from Celtra Duo (BL2-LT, BL3-LT), VITA Suprinity (0M1-HT), and VITA Enamic (0M1-HT). Each specimen was measured over standardized white and black backgrounds using distilled water, glycerin, eight commercial try-in pastes, or no medium (control). Lab* values and VITA Classic/3D-Master shade outputs were recorded with a dental spectrophotometer under D65/2 degrees conditions;a custom jig standardized specimen positioning and probe angulation. Repeated measurements (n = 5) were analyzed using linear mixed-effects models. Clinical interpretation used Delta E-00 perceptibility/acceptability (approximate to 0.8/1.8) and translucency thresholds (TPT00=0.62;TAT(00)=2.62). Results Relative to the no-media condition, both water and glycerin produced large, clinically perceptible color shifts across all ceramics (mean Delta E-00 approximate to 3.2-5.6;p < 0.001), while direct water-glycerin differences were smaller (approximate to 0.7-1.6). Translucency responses were material dependent: Celtra groups showed minimal Delta TP00 relative to glycerin (typically vertical bar Delta TP00 vertical bar <= similar to 0.3), Suprinity showed a modest reduction ( approximate to - 1 to - 2), and Enamic exhibited pronounced translucency loss ( approximate to - 5 to - 7), frequently exceeding translucency acceptability (vertical bar Delta TP00 vertical bar >= 2.62). Only selected Celtra BL2/BL3 conditions with translucent/light try-in pastes approached Delta E-00 acceptability (<= 1.8) on white backgrounds. Device-reported shade agreement so

关键词： angiography   percutaneous coronary intervention   prerandomization treatment plan   quantitative flow ratio   CAD   coronary artery disease   FFR   fractional flow reserve   iFR   instantaneous wave-free ratio   LCx   left circumflex coronary artery   MACE   major adverse cardiac event(s)   PCI   percutaneous coronary intervention   QFR   quantitative flow ratio   RCA   right coronary artery   SMD   standardized mean difference  

摘要： The optimization of a treatment plan developed on the basis of coronary angiography alone is recognized as one of the underlying rationales for the clinical benefits of physiology-guided percutaneous coronary intervention (PCI).

关键词： bladeless wind turbine   vortex-induced vibrations   mechanical rectification   cylindrical cam mechanism   urban wind energy   computational fluid dynamics   finite element analysis  

摘要： Global efforts to mitigate climate change and reduce reliance on fossil fuels have intensified interest in sustainable, urban-compatible wind energy technologies. Conventional wind turbines, however, remain limited in densely populated environments due to acoustic emissions, mechanical complexity, cost, and risks to avian wildlife. This study proposes and numerically evaluates a bladeless wind turbine concept based on vortex-induced vibrations (VIVs) as a simplified alternative to conventional bladed systems. The proposed design replaces rotating blades with a vertical mast that undergoes wind-induced oscillations, which are passively converted into unidirectional rotational motion using a cylindrical cam (CCAM) mechanism. The aerodynamic behavior and structural response of the system are investigated using computational fluid dynamics (CFD) and finite element analysis (FEA) under low-wind-speed conditions representative of urban environments. The numerical results indicate well-defined flow separation and wake formation conducive to VIV, along with low stress and displacement levels in the mast, supporting reliable mechanical engagement with the CCAM mechanism. These findings demonstrate the feasibility of mechanically rectified VIV-based bladeless wind turbines and highlight their potential as low-noise, low-impact solutions for decentralized and urban wind energy applications.

关键词： Shear bond strength   Orthodontic brackets   CAD/CAM ceramics   Surface treatment   Lithium disilicate   Feldspathic porcelain  

摘要： ObjectivesThis study evaluated the shear bond strength (SBS) of two types of orthodontic brackets (ceramic and metal) bonded to two CAD/CAM ceramic materials (feldspathic ceramic and lithium disilicate glass-ceramic), each subjected to different surface treatments, and assessed adhesive remnant index (ARI) *** and methodsSixty-four ceramic discs (1 mm thick;n = 32 per material) were prepared. Surface pretreatments were alumina air abrasion followed by phosphoric acid etching or hydrofluoric acid etching. Each subgroup was bonded with metal or ceramic brackets using a light-cured adhesive. SBS was measured with a universal testing machine, and ARI was assessed under a stereomicroscope. Three-way ANOVA tested the effects of ceramic type, bracket type, and surface treatment (alpha = 0.05), and chi-square tests compared ARI *** results demonstrated that the ceramic type significantly influenced SBS (p = 0.004). Lithium disilicate glass-ceramic exhibited higher SBS values than feldspathic ceramic. Bracket type also had a significant effect on SBS, regardless of ceramic type or surface treatment (p = 0.001). However, the applied surface treatments did not produce a significant difference in SBS (p = 0.546);phosphoric acid etching after alumina air abrasion yielded comparable results to hydrofluoric acid etching. ARI scores did not differ significantly among groups, and debonded surfaces showed no gross ceramic damage under *** type and bracket type significantly affected SBS, whereas surface pretreatment did not under the tested *** relevanceBalancing adequate bracket retention with safe debonding is essential for ceramic restorations. Comparable SBS between the two pretreatments and the absence of visible ceramic damage support conservative, clinically oriented conditioning protocols.

关键词： Assembly path planning   Interaction feature pair   Cognitive behaviors   Tolerances   Precision products  

摘要： Assembly path planning (APP) is a critical step in verifying the assembly feasibility of precision products. However, due to the loss of upstream knowledge, parts in mainstream APP technologies lack the cognitive ability of proactively playing as the agents of designers in computer-aided design (CAD) systems, thus leading to the heavy cognitive burdens of designers in APP and the great gap between APP and its upstream activities. A cognitive behavior based autonomous and integrated APP method for precision products is proposed in this paper, aiming at endowing parts with cognitive capabilities and integrating APP with its upstream stage of assembly modeling. In the method, the previously developed concept of interaction feature pair is extended as a comprehensive carrier to describe and capture upstream knowledge into parts, and to model cognitive behaviors of parts, thus enabling these parts to autonomously perceive APP environment, deform according to tolerances, plan collision-free paths, and establish assembly constraints that are traditionally processed at assembly modeling stage. On this basis, key implementation algorithms for the cognitive behavior models are developed. Case studies on a simplified smartphone and a jet engine validate the feasibility of the autonomous and integrated CAD APP approach. Results indicate that, the time and manual operations used for the two cases are reduced by at least 24% and 93%, respectively;and the effects of tolerance on precision assembly can be intuitively and quantitatively evaluated. The study may potentially provide reference to more intelligent APP technologies for precision products in the future.

关键词： coparenting   alliance   CAM   paths to parenthood   LGBTQ   diversity   IPA  

摘要： As diverse family structures are increasingly prominent, the purpose of this study was to introduce the Coparenting Alliance Model (CAM) as a family framework. This qualitative research explored the lived experiences of five gay and lesbian individuals, coparenting children with a non-romantic partner, either homosexual or heterosexual. The aim was to gain insights into the interpersonal dynamics, logistical organization, challenges, and necessary skills involved in creating a cohesive unit focused on the well-being of the children. Using Interpretative Phenomenological Analysis (IPA), the analyzed data uncovered themes clustered around three distinct phases in participants' path to coparenting: the initial desire for children and negotiation of family form;the structuring of the coparenting alliance;and the ongoing management of daily life. The research implications can be of significance for understanding and improving the dynamics of non-romantic parents raising children together.

关键词： Pepper   Cold stress   CaD27   Functional identification  

摘要： Strigolactones (SLs) are crucial phytohormones involved in plant growth and stress adaptation. However, the role of SL biosynthetic genes, particularly CaD27, in pepper under cold stress remains unclear. In this study, we identified three CaD27 genes in the pepper genome, all harboring promoter regions enriched with phytohormone and stress-responsive cis-elements. Functional analysis via virus-induced gene silencing (VIGS) revealed that silencing CaD27.1 or CaD27.3 markedly impaired cold tolerance. Under cold stress, silenced plants exhibited excessive accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), along with elevated relative electrolyte leakage (REL). Concurrently, antioxidant enzyme activities and the expression of related genes were significantly suppressed. The expression of key cold-responsive genes was also downregulated. Furthermore, abscisic acid (ABA) biosynthesis was compromised, as evidenced by reduced levels of ABA and downregulated expression of ABA synthesis genes (CaNCED1, CaABA2, CaAAO4) and the receptor gene CaPYL2, whereas the ABA catabolism gene CaCYP707A4 remained unchanged. This ABA deficiency led to impaired stomatal closure and exacerbated wilting. Our findings demonstrate that CaD27.1 and CaD27.3 positively regulate cold tolerance in pepper by modulating ROS scavenging and ABA-mediated stomatal responses. Collectively, our findings identify CaD27.1 and CaD27.3 as positive regulators of cold tolerance in pepper and establish them as promising candidate genes for breeding cold-resilient pepper varieties.

关键词： Large language models   Coronary Stenosis   Coronary computed tomography angiography   Plaque burden   Management  

摘要： ObjectivesTo evaluate the performance of large language models (LLMs), including retrieval-augmented generation (RAG)-based approaches, in extracting components and management recommendations from structured coronary computed tomography angiography (CCTA) reports according to the Coronary Artery Disease Reporting and Data System (CAD-RADS 2.0). Materials and methodsA total of 320 fully structured CCTA reports were analyzed using LLM. Closed-source standard ChatGPT-5, NotebookLM (RAG-based model), and a RAG-adapted ChatGPT-5 model (ChatGPT-5-RAG) were used. Each model extracted the CAD-RADS category, plaque burden, presence of high-risk plaque (HRP), other modifiers, full score, and management recommendations in accordance with the CAD-RADS 2.0 guidelines. We compared LLM outputs with reference standards determined by two expert cardiovascular radiologists. ResultsChatGPT-5-RAG showed the highest accuracy for CAD-RADS classification (0.959, 95% CI: 0.932-0.976), plaque burden (0.912, 95% CI: 0.876-0.939), HRP detection (0.988, 95% CI: 0.968-0.995), other modifiers (0.950, 95% CI: 0.920-0.969), and full score (0.828, 95% CI: 0.783-0.866). Closed-source ChatGPT-5 showed the weakest performance across all components. Significant statistical differences were found among the three models (p < 0.001). Management recommendations were qualitatively rated on a three-point Likert scale;although agreement between models was low, ChatGPT-5-RAG and NotebookLM performed almost perfectly (median 3 points). ConclusionThis study demonstrates that RAG-enhanced LLMs significantly improve accuracy and reliability in extracting CAD-RADS 2.0 components and generating clinical management recommendations. The findings highlight the potential of RAG-based LLMs as innovative, explainable tools for automated and standardized CCTA reporting in clinical radiology workflows.