Harnessing defocus blur to recover high-resolution information in shape-from-focus technique

Traditional shape-from-focus (SFF) uses focus as the singular cue to derive the shape profile of a 3D object from a sequence of images. However, the stack of low-resolution (LR) observations is space-variantly blurred because of the finite depth of field of the camera. The authors propose to exploit the defocus information in the stack of LR images to obtain a super-resolved image as well as a high-resolution (HR) depth map of the underlying 3D object. Appropriate observation models are used to describe the image formation process in SFF. Local spatial dependencies of the intensities of pixels and their depth values are accounted for by modelling the HR image and the HR structure as independent Markov random fields. Taking as input the LR images from the stack and the LR depth map, the authors first obtain the super-resolved image of the 3D specimen and use it subsequently to reconstruct a HR depth profile of the object.     

Enhanced bioactivity of ZnO nanoparticles—an antimicrobial study

In this study, we investigate the antibacterial activity of ZnO nanoparticles with various particle sizes. ZnO was prepared by the base hydrolysis of zinc acetate in a 2-propanol medium and also by a precipitation method using Zn(NO₃)₂ and NaOH. The products were characterized by x-ray diffraction (XRD) analysis, transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. Bacteriological tests such as minimum inhibitory concentration (MIC) and disk diffusion were performed in Luria-Bertani and nutrient agar media on solid agar plates and in liquid broth systems using different concentrations of ZnO by a standard microbial method for the first time. Our bacteriological study showed the enhanced biocidal activity of ZnO nanoparticles compared with bulk ZnO in repeated experiments. This demonstrated that the bactericidal efficacy of ZnO nanoparticles increases with decreasing particle size. It is proposed that both the abrasiveness and the surface oxygen species of ZnO nanoparticles promote the biocidal properties of ZnO nanoparticles.     

Pole assignment with output feedback

For pole assignment with output feedback, appropriate partitioning of the coefficient matrix of the system numerator transfer function matrix leads to simplified design equations to solve for the vectors of the unity rank output feedback matrix. This concept is applied to derive the pole placement equations for the proportional-derivative output feedback dynamic compensator. The simplicity of the design procedure is illustrated with a numerical example.     

Oxygen potential studies on hypostoichiometric uranium-cerium mixed oxide

Oxygen potential measurements on $\text{(U,Ce)0}{}_{\mathrm{2?x}}$ with $\text{Ce/U + Ce}$ ratios of 0.2 to 0.5 were carried out at 1073 and 1173 K by a gas equilibration method employing $\text{H}{}_2\text{0/H}{}_2$ carrier gas. A new wet chemical method based on potentiometric titrations was used to determine and cross check the O/M ratios of the equilibrated samples. Lattice parameters of stoichiometric oxides were determined by x-ray diffraction. The oxygen potentials and their dependence on O/M and composition are discussed and compared with available literature data.     

Aluminium as anode in primary alkaline batteries. Influence of additives on the corrosion and anodic behaviour of 2S aluminium in alkaline citrate solution

The inhibitive effects of various additives on the corrosion of 2S aluminium in 4N NaOH containing calcium oxide and sodium citrate (base electrolyte) have been examined by studying the self corrosion, anodic polarization and anode efficiency of 2S aluminium in solutions containing different additives. It has been found that among the different additives investigated, those forming anions in solution act favourably.     

Purification and properties of sulfite oxidase from human liver

Sulfite oxidase has been purified to near homogeneity from human liver. Properties of the molecule have been investigated and compared to those of the rat liver enzyme which has been isolated in a pure form. Both proteins exist as dimeric molecules with one molybdenum and one cytochrome b5-type heme per sub-unit. The human enzyme has a slightly larger subunit molecular weight (61,100 vs. 57,200 daltons) and is a more negatively charged molecule. Decreased reactivity of the human enzyme with various electron acceptors suggests the presence of nonfunctional molybdenum centers in a portion of the molecules isolated. Human liver sulfite oxidase cross-reacts strongly with antibody prepared against the rat liver enzyme. Human enzyme activity is precipitated by antibody at concentrations about twofold greater than required for comparable complexation of rat sulfite oxidase.     

Networked hardware assisted key image and chaotic attractors for secure RGB image communication

In multimedia communication, significance of the images for data representation is noteworthy. In this context, secure transmission of images over open channel has become a challenging task. Creation of different strategies in improving the secure image transmission always has a demand. The proposed work suggests an RGB image encryption with the confluence of attractors and hardware triggered key image in which confusion and diffusion were accomplished by Lorenz, Lü and Cellular Automata attractors. The uniqueness of proposed encryption scheme is a key image generation module through cascaded Ring Oscillator circuit which creates M?×?N key image for diffusion of pixels. Facilitating the authenticated networked access to key image generation hardware enables the secure server-client architecture for a variety of secure image transfer applications. The proposed approach is a hardware – software codesign which possesses a good keyspace, improved key sensitivity and satisfies the various statistical parameters thus offering substantial resistance to differential, occlusion and chosen plaintext attacks on RGB images.     

PROCESS OPTIMIZATION IN ULTRAFILTRATION: FLUX-TIME CONSIDERATIONS IN THE PURIFICATION OF MACROMOLECULES

An empirical model was developed to describe the flux of a complex milk protein suspension under ultrafiltration and diafiltration conditions. Flux decreased during ultrafiltration, but increased during diafiltration as the permeable solids concentration decreased. The “gel” model based on film theory was modified to describe the flux in terms of both retained and permeable solutes. The least-time processing strategy for a given end product concentration was also modelled and identified for this protein system. In general, ultrafiltration followed by diafiltration is best if protein purification is the goal.