Normal vector generation for sampled data using fourier filtering

A three-dimensional surface is a useful graphic representation of a two-dimensional function which has been sampled on a regular grid. Shading the surface to simulate the effects of direct lighting makes visible small changes in the surface orientation, and enhances realism when the data represents a physical surface such as terrain. Shading interpolation calculations and surface patch generation techniques require the specification of a surface normal vector (or related slope information) at each sample point. These normal vectors are usually generated by averaging local data such as the normal vectors of the surfaces of a triangular mesh connecting the points. This paper describes a technique which uses Fourier filtering to generate normal vectors for two-dimensional sampled data. Images and analysis of frequency spectra are included to show how this technique preserves detail which is lost using the averaging method. Performance figures show that this enhancement of detail in the final image can be achieved for only a small increase in computation time.     

Thermal expansion and magnetostriction of Nd16Fe76B8 alloy

The spontaneous magnetization variation in the temperature range from room temperature to 500 °C was examined by correlation with thermal expansion measurement. Unaligned and aligned sintered specimens were examined to study the temperature dependencies of their dimensions resulting from spontaneous magnetostriction and thermal expansion. Above the Curie temperature (315 °C) all specimens showed the same normal thermal expansion, whilst below this temperature their thermal expansions were quite different and anomalous.     

On the Virtualization of CUDA Based GPU Remoting on ARM and X86 Machines in the GVirtuS Framework

The astonishing development of diverse and different hardware platforms is twofold: on one side, the challenge for the exascale performance for big data processing and management; on the other side, the mobile and embedded devices for data collection and human machine interaction. This drove to a highly hierarchical evolution of programming models. GVirtuS is the general virtualization system developed in 2009 and firstly introduced in 2010 enabling a completely transparent layer among GPUs and VMs. This paper shows the latest achievements and developments of GVirtuS, now supporting CUDA 6.5, memory management and scheduling. Thanks to the new and improved remoting capabilities, GVirtus now enables GPU sharing among physical and virtual machines based on x86 and ARM CPUs on local workstations, computing clusters and distributed cloud appliances.     

Material dependent dielectric breakdown model

Dielectric breakdown in ceramics and composites has previously been determined by the dielectric breakdown model, dependent only on the electric field strength at a certain point and intermolecular distance in a lattice. This does not take into account quantum aspects of the lattice structure into account. The present model takes into account quantum variations of particles in conjunction with different particle characteristics. Dielectric breakdown patterns are characterised by their quantum breakdown probabilities and studies are carried out as a function of the applied electric field, temperature and specific material constants responsible for breakdown, such as the mean free path and the potential barrier present.     

Phase Equilibrium Measurements of Sacha Inchi Oil (<Emphasis Type="Italic">Plukenetia volubilis</Emphasis>) and CO<Subscript>2</Subscript> at High Pressures

New data on phase equilibria for Sacha inchi seed oil in carbon dioxide have been measured using a variable volume cell phase equilibria system at temperatures of 303, 313 and 323 K and at pressures ranging from 4.3 to 27.7 MPa. The CO₂ mole fraction varied from 0.7488 to 0.9997. At the studied concentrations, phase transitions of vapor-liquid, liquid-liquid-vapor and liquid-liquid were observed. Sacha inchi oil contains 47% of omega-3 fatty acids, with a ratio of 0.76:1 for omega-6:omega-3, which is good for human health. The Peng-Robinson equation of state was used to describe the experimental data. A qualitative agreement was obtained between experimental and calculated data for the binary system CO₂ and Sacha inchi seed oil.     

Relationships between dopants,microstructure and the microwave dielectric properties of ZrO2-TiO2-SnO2 ceramics

Ceramics with compositions in the solid solution region of the ZrO₂-TiO₂-SnO₂ equilibrium diagram are finding wide application as dielectrics in filters for communications and radar systems operating at microwave frequencies. Commercially available compositions often incorporate sintering aids and dopants to reduce processing temperatures and modify the dielectric properties. However, the mechanism through which these additives influence dielectric loss is not obvious. The role of zinc oxide as a sintering aid and lanthanum and niobium as dopants, their effect upon microstructural development and their correlation with dielectric loss at microwave frequencies were investigated. For specimens of density greater than 90% theoretical, the influences of defect chemistry upon dielectric loss appear to dominate those of the microstructure. Properties close to those which might be considered intrinsic were attained through sintering for periods of up to 128h. Doping with lanthanum is detrimental to the dielectric loss, particularly after long sintering times.     

Lipid composition of subcellular membranes from larvae and prepupae ofDrosophila melanogaster

Subcellular membranes were analyzed for their lipid composition and protein content at two developmental points representing the third instar wandering larvae and prepupal stages ofDrosophila. At both stages, phosphatidylethanolamine (PE) and phosphatidylcholine (PC) were the major constituents with phosphatidylinositol (PI), phosphatidylserine (PS), diphosphatidylglycerol (DPG) and phosphatidic acid (PA) being relatively minor components. In total homogenates and in the nuclear-enriched fraction there was no significant difference in the phospholipid composition of the wandering larvae and prepupae. In mitochondria only a significant increase in the minor component PS was observed in the prepupae. In lysosomal membranes on the other hand, the relative abundance of the major components PE and PC increased in the prepupae although the molar ratios of the two lipids remained almost constant. The fatty acid composition of the phospholipids remained virtually unchanged in all of the fractions examined, including the lysosomes, and there was no evidence of lipid peroxidation. With regard to cellular degeneration and the involvement of lysosomes, we conclude that mechanisms other than gross modification of the lipid and/or lipid/protein ratio of their membranes are involved in the liberation of the acid phosphatase contents.     

Study of the relation between the phosphorus content of coal and coke

Established methods for the determination of phosphorus in coal and coke were compared and found to give results in satisfactory agreement. The method for the determination of phosphorus described in BS 1016, ‘Methods for the analysis and testing of coal and coke’, Part 9, 1977 was used to study the relation between the phosphorus content of coals and their corresponding cokes. The cokes were prepared on laboratory, test oven and industrial scales, by the carbonization of various bituminous coals within the range of volatile matter yield of 16–40 wt%. The determined values of the phosphorus contents of these cokes and their parent coals indicated that the phosphorus present in the coal is completely retained in cokes carbonized to temperatures between 900 and 1050 °C. On the basis of these experimental results it is suggested that the phosphorus content of coke can generally be calculated from a knowledge of the phosphorus content of the coal and the coke yield with an accuracy which is sufficient for normal requirements.