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Recently, advanced visualizing techniques in computer graphics have considerably enhanced the visual appearance of synthetic models. To realize enhanced visual graphics for synthetic medical effects, the first step followed by rendering techniques involves attaching albedo textures to the region where a certain graphic is to be rendered. For instance, in order to render wound textures efficiently, the first step is to recognize the area where the user wants to attach a wound. However, in general, face indices are not stored in sequential order, which makes sub-texturing difficult. In this paper, we present a novel mesh tagging algorithm that utilizes a task for mesh traversals and level extension in the general case of a wound sub-texture mapping and a selected region deformation in a three-dimensional (3D) model. This method works automatically on both regular and irregular mesh surfaces. The approach consists of mesh selection (MS), mesh leveling (ML), and mesh tagging (MT). To validate our approach, we performed experiments for synthesizing wounds on a 3D face model and on a simulated mesh. [ABSTRACT FROM AUTHOR]

The solubility of sodium dodecyl sulfate (SDS) in water at temperatures between (270.5 and 281.3) K near propane and carbon dioxide hydrate-forming conditions was determined by directly sampling the SDS solution from a high-pressure reactor. The SDS solubility near propane or carbon dioxide hydrate-forming conditions is identical to that at ambient conditions. The results indicate that the Krafft point for SDS does not shift to a temperature below 281 K even in the presence of high-pressure propane or carbon dioxide. [ABSTRACT FROM AUTHOR]

The role of sodium dodecyl sulfate (SDS) in methane hydrate formation is investigated in a nonstirred batch reactor. Addition of SDS reduces the induction time, but no systematic trend is observed between induction times and SDS concentrations. The hydrate growth is analyzed by using a diffusion-reaction kinetics model with an assumption that crystallization occurs only in the liquid film at the gas−liquid interface. At the start of hydrate growth, the apparent rate constant increases linearly with increasing aqueous SDS concentrations. The apparent rate constant during hydrate growth increases as more available gas−liquid interface is generated. SDS not only increases hydrate nucleation rate by reducing the interfacial tension between hydrate and liquid but also accelerates hydrate growth rate by increasing the total surface area of hydrate particles and the gas−liquid interfacial area. [ABSTRACT FROM AUTHOR]

Epoxy/BaTiO3 composites have been of great interest as embedded capacitor materials, mainly due to high dielectric constant of ceramic powders, and good process compatibility of epoxy with printed circuit boards (PCBs). However, one of the potential problems of epoxy/BaTiO3 composite is the dielectric relaxation at gigahertz range. In this paper, epoxy/SrTiO3 composite embedded capacitor films (ECFs) were fabricated for high-frequency applications. Dielectric constants of epoxy/SrTiO3 composite embedded capacitor films with various SrTiO3 particles loading for three different commercial SrTiO3 powders were measured, and experimental data were fitted to the Lichtenecker equation for the prediction of the effective dielectric constant of SrTiO3 powders in epoxy/SrTiO3 composite ECFs. Using a rectangular cavity resonator method, dielectric constants of epoxy/SrTiO3 composite ECFs were measured at gigahertz range (1-10 GHz). At gigahertz frequencies, dielectric constants of epoxy/SrTiO3 composite ECFs were nearly constant. In contrast, epoxy/BaTiO3 composite ECFs showed decrease of dielectric constants above 5 GHz. Therefore, it is concluded that epoxy/SrTiO3 composite ECFs can be more effectively to be applied for high-frequency applications. [ABSTRACT FROM AUTHOR]

A new thermodynamic calculation procedure is introduced to predict the equilibrium conditions of multicomponent gas hydrates containing hydrogen. This new approach utilizes an excess Gibbs potential term to account for second- or higher-order water-cavity distortions due to the presence of multiple guest species. The excess Gibbs potential describes changes in reference chemical potentials according to different compositions of guest mixtures in the hydrate phase. To determine the equilibrium conditions of multicomponent gas hydrates, the excess Gibbs potential term is incorporated to the Lee-Holder model along with the Zele-Lee-Holder cell distortion model. For binary gas hydrates between hydrogen and the other gas molecule, the predicted equilibrium pressure deviates within 10-20% from the experimental value. For the ternary and quaternary mixture hydrates, the model prediction is reasonably good but its error increases with increasing pressure and temperature under the presence of THF. [ABSTRACT FROM AUTHOR]

Bulk amorphous NiTiZrSiSn feedstock was sprayed using a high velocity oxy-fuel spraying process. In order to evaluate the amorphous formability in view of chemical instability, the oxygen to hydrogen gas flow rate ratio was changed at the constant total gas flow rate. Flame gas enthalpy was increased with the O2/H2 gas ratio. In-flight particle melting state was improved with the increase of oxidizer flow rate. Accordingly, porosity as well as unmelted particle size and density were decreased. For the amorphous phase fraction within an as-sprayed coating, it was decreased with the oxygen flow rate. From the thermal analysis and X-ray diffraction, the effects of O2/H2 gas ratio on the crystallization of HVOF sprayed bulk amorphous NiTiZrSiSn could be divided into two categories. One is due to the solid-state crystallization during flight along the low gas enthalpy flame. The other results from the destabilization of bulk amorphous feedstock due to the chemical composition change resulting from in-flight particle oxidation at the higher oxygen gas flow rate. Oxidation degree was different from the O2/H2 gas ratio and it had influences on the glass formability [ΔTx] and crystalline phase. Increase of oxide phase fraction was parallel to that of γ-Ni solid solution. [ABSTRACT FROM AUTHOR]

This paper addresses a new calculation approach for the prediction of hydrogen hydrate equilibrium by introducing the concept of a single hydrogen cluster in one cavity. By integrating ab initio calculations with classical statistical thermodynamics, this approach enables the van der Waals model to predict the dissociation pressure of hydrogen hydrates. Compared to hydrates formed by light hydrocarbon gases, structure II (sII) hydrogen hydrates stably encage two and four hydrogen molecules in the small and large cavities, respectively. By treating two hydrogen molecules or four hydrogen molecules as one rigid body cluster, we determine ab initio binding energies between water molecules and hydrogen clusters at the MP2 level with the 6-31++G(2d,2p) basis set. These binding energies will be used to determine the parameters of the Exp-6 potential function from which the smooth cell potential and the Langmuir constant of each cluster are calculated. Then, the dissociation pressure is determined using the Zele−Lee−Holder cell distortion model:  105, 625, and 2000 bar at 150, 200, and 250 K, respectively. [ABSTRACT FROM AUTHOR]