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We present a novel divergence free mixture model for multiphase flows and the related fluid‐solid coupling. The new mixture model is built upon a volume‐weighted mixture velocity so that the divergence free condition is satisfied for miscible and immiscible multiphase fluids. The proposed mixture velocity can be solved efficiently by adapted single phase incompressible solvers, allowing for larger time steps and smaller volume deviations. Besides, the drift velocity formulation is corrected to ensure mass conservation during the simulation. The new approach increases the accuracy of multiphase fluid simulation by several orders. The capability of the new divergence‐free mixture model is demonstrated by simulating different multiphase flow phenomena including mixing and unmixing of multiple fluids, fluid‐solid coupling involving deformable solids and granular materials. [ABSTRACT FROM AUTHOR]

Abstract: The material point method (MPM) has attracted increasing attention from the graphics community, as it combines the strengths of both particle‐ and grid‐based solvers. Like the smoothed particle hydrodynamics (SPH) scheme, MPM uses particles to discretize the simulation domain and represent the fundamental unknowns. This makes it insensitive to geometric and topological changes, and readily parallelizable on a GPU. Like grid‐based solvers, MPM uses a background mesh for calculating spatial derivatives, providing more accurate and more stable results than a purely particle‐based scheme. MPM has been very successful in simulating both fluid flow and solid deformation, but less so in dealing with multiple fluids and solids, where the dynamic fluid‐solid interaction poses a major challenge. To address this shortcoming of MPM, we propose a new set of mathematical and computational schemes which enable efficient and robust fluid‐solid interaction within the MPM framework. These versatile schemes support simulation of both multiphase flow and fully‐coupled solid‐fluid systems. A series of examples is presented to demonstrate their capabilities and performance in the presence of various interacting fluids and solids, including multiphase flow, fluid‐solid interaction, and dissolution. [ABSTRACT FROM AUTHOR]

Sharp edges are important shape features and their extraction has been extensively studied both on point clouds and surfaces. We consider the problem of extracting sharp edges from a sparse set of colour-and-depth (RGB-D) images. The noise-ridden depth measurements are challenging for existing feature extraction methods that work solely in the geometric domain (e.g. points or meshes). By utilizing both colour and depth information, we propose a novel feature extraction method that produces much cleaner and more coherent feature lines. We make two technical contributions. First, we show that intensity edges can augment the depth map to improve normal estimation and feature localization from a single RGB-D image. Second, we designed a novel algorithm for consolidating feature points obtained from multiple RGB-D images. By utilizing normals and ridge/valley types associated with the feature points, our algorithm is effective in suppressing noise without smearing nearby features. [ABSTRACT FROM AUTHOR]

Although a patchwork of projects shows a process of agriculture intensification in North China during the Neolithic, the impact of cereal farming on animal husbandry and their mutual interaction remain cloudy. This study reports bone collagen δ13C and δ15N of humans and animals from Wayaogou (ca 6.5-6.0 kyrs bp) and Dongying (ca 5.9-5.6 kyrs bp, 4.6-4.0 kyrs bp) to explore temporal trend of livestock raising and particularly the importance of millet fodder to stock raising practices in the Wei River valley, North China. The isotopic evidence overall shows that millet products increased in human and domestic animal diets during the mentioned chronological span. δ13C values of pigs and dogs at Dongying are higher than those at Wayaogou, implying that the importance of millet nutrients increased to animal husbandry diachronically. Interestingly, δ13C results of domestic cattle of Dongying late phase (−14.1 ± 1.1‰, N = 5) are more enriched than Wayaogou wild Bos (−17.8 ± 0.3‰, N = 3), indicating that millet fodder had taken a significant place in early cattle husbandry. Besides, differences between Bos species of the two periods also imply that δ13C values of bone collagen constitute a potential indicator for tracing the origin of cattle husbandry in North China. In addition, domestic sheep at Dongying produced similar isotope data to wild ovicaprid at Wayaogou, suggesting that they possibly had grazed for the most in grassland and therefore experienced a different lifestyle from cattle. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We present a data-driven method for automatically recoloring a photo to enhance its appearance or change a viewer's emotional response to it. A compact representation called a RegionNet summarizes color and geometric features of image regions, and geometric relationships between them. Correlations between color property distributions and geometric features of regions are learned from a database of well-colored photos. A probabilistic factor graph model is used to summarize distributions of color properties and generate an overall probability distribution for color suggestions. Given a new input image, we can generate multiple recolored results which unlike previous automatic results, are both natural and artistic, and compatible with their spatial arrangements. [ABSTRACT FROM AUTHOR]

Sj16, a 16-kDa protein produced by Schistosoma japonicum, has been demonstrated to have anti-inflammatory effect. However, the possible mechanism of these phenomena has not been discovered. Here, we tried to touch it with arthritis rats' model induced by injection of complete Freund's adjuvant (CFA). A set of pathogenic characters were observed in CFA-treated rat, including local and systematic read-out, which showed the model successfully set up. After administration of rSj16 (recombinant Sj16) in vivo, paw swelling reduced significantly and in a dose-dependent manner, the level of TNF-α, IL-1β and NO decreased and IL-10 in the serum increased. In vitro, rSj16 reversed the augmented surface expression of CD80, CD86, CD54 and OX6 induced by lipopolysaccharide (LPS) in bone marrow-derived DCs (BMDCs), whereas endocytotic capacity of rSj16-treated dendritic cell (DC) was profoundly increased. IL-12p70 released from rSj16-treated BMDC was decreased but IL-10 increased. Further, following incubation with rSj16 primed BMDCs, the sensitized T cells exhibited increased production of anti-inflammatory IL-10 and IL-4 and decreased production of IL-12p70 and IFN-γ. Collectively, these results implied that rSj16 alleviated CFA-induced arthritis, and the possible mechanisms may be its interruption of maturation and function of DCs. rSj16 could be a potential therapeutic agent against rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

This paper presents a new combination of the finite-difference time-domain (FDTD) method and the least-squares support vector machines (LS-SVM) technique. The LS-SVM is a statistical-learning method which has a self-contained basis of statistical-learning theory and excellent learning performance. A short segment of an FDTD record is used to train the LS-SVM predictor in order to obtain an accurate future realization. Numerical simulations for two typical microwave filters demonstrate that the LS-SVM method can achieve good forecasting accuracy and the efficiency of the FDTD method can be improved by up to 70%. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 296–299, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20615 [ABSTRACT FROM AUTHOR]

In this paper, a low-pass filter (LPF) with a uniplanar compact electromagnetic band-gap (UC-EBG) structure in the ground plane is investigated. The finite-difference time-domain (FDTD) method combined with the modified matrix pencil (MMP) method is applied to analyze this complicated structure. A short segment of an FDTD record is used to train the MMP predictor, and an accurate future realization can be obtained. The numerical simulation for low-pass filters with UC-EBG demonstrates that the efficiency of the FDTD method can be improved by up to 70%. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 37–41, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20540 [ABSTRACT FROM AUTHOR]