Optimizing BRDF orientations for the manipulation of anisotropic highlights

This paper introduces a system for the direct editing of highlights produced by anisotropic BRDFs, which we call anisotropic highlights. We first provide a comprehensive analysis of the link between the direction of anisotropy and the shape of highlight curves for arbitrary object surfaces. The gained insights provide the required ingredients to infer BRDF orientations from a prescribed highlight tangent field. This amounts to a non‐linear optimization problem, which is solved at interactive framerates during manipulation. Taking inspiration from sculpting software, we provide tools that give the impression of manipulating highlight curves while actually modifying their tangents. Our solver produces desired highlight shapes for a host of lighting environments and anisotropic BRDFs.     

The effect of trans-isomers on the physical properties of hydrogenated oils

Data have been presented which indicate a positive relationship between thetrans-isomer content of a hydrogenated oil and the congeal point, Wiley melting-point, and solids index. It has also been shown that cottonseed oil and soybean oil undergo substantially the same type of reaction under identical hydrogenating conditions. This conclusion is based on the relationship oftrans-isomer formation to total reduction in unsaturation up to the point that equilibrium is reached and saturation of thetrans-isomers occurs. This equilibrium was noted at between 60–70 iodine value. The relationship oftrans-isomer formation to the total reduction in double bonds can be expressed as the hydrogenation index. This is a reliable indication of the type of reaction taking place up to the point where appreciable hydrogenation of thetrans-isomers occur.     

The effect of solution variables on the solution of cellulose in dimethyl sulfoxide

Through the study of the effects of concentration, temperature, and molar ration (of paraformaldehyde to cellulose) on solution viscosity and per cent transmittance (at 530 nm), it has been demonstrated that cellulose solutions in dimethyl sulfoxide (DMSO) are readily produced. By heating 1, 2, and 50 to 100 parts by weight of cellulose, paraformaldehyde, and DMSO, respectively, extremely viscose cellulose solutions and gels were prepared. Solutions with concentrations as high as 10% were prepared. However, the optimum conditions to effect complete cellulose solution in DMSO at 75°C were found to be 0.5% cellulose and 0.8 and 1.0% paraformaldehyde. This corresponds to a paraformaldehyde-to-cellulose molar ratio of about 10:1.     

Microemulsions with excellent water solubilizing capacity at high hydrocarbon levels with quaternary ammonium salts as surfactants

In W/O microemulsions prepared by adding dry surfactant to a mixture of 85% heptane or toluene and 15% pentanol, then titrating with water, systems using quaternary ammonium salts have been shown to be capable of solubilizing much larger amounts of water than systems using the anionic sodium dodecyl sulfate. In homologous series in the range C₁₂ to C₁₆ it would appear that, with one exception, longer chain length quaternary salts are more effective at solubilizing water than are shorter chain length compounds. With quaternary salts of equal chain length, pyridinium salts are more effective at solubilizing water at high surfactant concentrations than are corresponding trimethyl salts.     

Dynamic mechanical analysis of polymers in the liquid state: Use of a perforated shim stock support

This report summarizes some initial results on the use of a perforated brass shim stock support to extend the useful range of dynamic mechanical testing well over 100 degrees above the traditional limiting polymer softening points of T_g or T_m. Weak secondary relaxations were observed above T_g in both polyisobutylene (PIB) and polystyrene (PS) homopolymer, copolymer, and blend systems and above T_m in gutta percha (trans-polyisoprene). The DuPont 981 Dynamic Mechanical Analyzer (DMA)–990 Thermal Analyzer system was used to characterize these weak liquid state processes. The DMA instrument deforms the specimen in flexure, thus minimizing the shear component present in some other techniques. Specimen-coating weights are typically in the range 20–40 mg. The perforations are particularly useful for polymers having low inherent adhesion to metals or systems which are very brittle in the glassy state, e.g., low MW PS's and many methacrylates.     

Thermomechanical analysis of Tg and T > Tg transitions in polystyrene

Phenomenological softening points were measured on a series of 13 anionic, nearly monodisperse, atactic polystyrenes using a DuPont 943 thermomechanical analyzer (TMA) in a penetration mode. Although TMA cannot identify the nature of the “transition” observed as such, the results obtained support the evidence for the T_g, T_ll, and T′_ll transition in polystyrene discussed in recent literature. T_g and T_ll were found to vary with molecular weight in a systematic manner, while T′_ll could only be observed at very high molecular weight. The technique appears to be quite useful in offering rapid and reproducible information on the various transitions in the liquid state of polystyrene.     

Molecular modeling of antibody-antigen complexes between the Brucella abortus O-chain polysaccharide and a specific monoclonal antibody

A molecular model of the binding site of an anti-carbohydrateantibody (YsT9.1) has been developed using computer-assistedmodeling techniques and molecular dynamics calculations. Sequencehomologies among YsT9.1 and the Fv regions of McPC603, J539and human Bence-Jones protein REI, all of which have solvedcrystal structures, provided the basis for the modeling. Thegroove-type combining site model had a topography which wascomplementary to low energy confonners of the polysaccharide,a Brucella O-antigen, and the site could be almost completelyfilled by a pentasaccharide epitope in either of two dockingmodes. Putative interactions between this epitope and the antibodyare consistent with the known structural requirements for bindingand lead to the design of oligosaccharide inhibitors that probethe veracity of the modeled docked complex. Ultimately boththe Fv model and the docked complex will be compared with independentcrystal structures of YsT9.1 Fab with and without pentasaccharideinhibitor, currently at the stage of refinement.     

Ethereum smart contract security research: survey and future research opportunities

Blockchain has recently emerged as a research trend, with potential applications in a broad range of industries and context. One particular successful Blockchain technology is smart contract, which is widely used in commercial settings (e.g., high value financial transactions). This, however, has security implications due to the potential to financially benefit froma security incident (e.g., identification and exploitation of a vulnerability in the smart contract or its implementation). Among, Ethereum is the most active and arresting. Hence, in this paper, we systematically review existing research efforts on Ethereum smart contract security, published between 2015 and 2019. Specifically, we focus on how smart contracts can be maliciously exploited and targeted, such as security issues of contract program model, vulnerabilities in the program and safety consideration introduced by program execution environment. We also identify potential research opportunities and future research agenda.