Robust PCA-based solution to image composition using augmented Lagrange multiplier (ALM)

Computational photography relies on specialized image-processing techniques to combine multiple images captured by a camera to generate a desired image of the scene. We first consider the high dynamic range (HDR) imaging problem. We can change either the exposure time or the aperture while capturing multiple images of the scene to generate an HDR image. This paper addresses the HDR imaging problem for static and dynamic scenes captured using a stationary camera under various aperture and exposure settings, when we do not have any knowledge of the camera settings. We have proposed a novel framework based on sparse representation which enables us to process images while getting rid of artifacts due to moving objects and defocus blur. We show that the proposed approach is able to produce significantly good results through dynamic object rejection and deblurring capabilities. We compare the results with other competitive approaches and discuss the relative advantages of the proposed approach.     

Pattern‐Similarity‐Based Model for Time Series Prediction

This research proposes a pattern/shape‐similarity‐based clustering approach for time series prediction. This article uses single hidden Markov model (HMM) for clustering and combines it with soft computing techniques (fuzzy inference system/artificial neural network) for the prediction of time series. Instead of using distance function as an index of similarity, here shape/pattern of the sequence is used as the similarity index for clustering, which overcomes few of the shortcomings associated with distance‐based clustering approaches. Underlying hidden properties of time series are captured with the help of HMM. The prediction method used here exploits the pattern identification prowess of the HMM for cluster selection and the generalization and nonlinear modeling capabilities of soft computing methods to predict the output of the system. To see the validity of the proposed method in the real‐life scenario, it is tested on four different time series. The first is a benchmark Mackey–Glass time series, which is tested for delay parameters τ = 17 and τ = 30. The remaining time series are monthly sunspot data time series, Laser data time series and the last is Lorenz attractor time series. Simulation results show that the proposed method provide a better prediction performance in comparison with the existing methods.     

Influence of electron beam radiation on mechanical and thermal properties of styrene‐butadiene‐styrene block copolymer

Electron beam crosslinking of elastomers is a special type of crosslinking technique that has gained importance over conventional chemical crosslinking method, because the former process is fast, pollution free, and simple. The technique involves the impingement of high‐energy electrons generated from electron accelerators and the subsequent production of free radicals on target elastomers. These radicals result in crosslinking of elastomers via radical–radical coupling. In the process, some chain scission may also take place. In this work, a high‐vinyl (～ 50%) styrene‐butadiene‐styrene (S‐B‐S) block copolymer was used as the base polymer. An attempt was made to see the effect of electron beam radiation on the mechanical and thermal properties of the block copolymer. Radiation doses were varied from 25 to 300 kGy. Mechanical properties like tensile strength, elongation at break, modulus at different elongations, hardness, tear strength, crosslink density, and crosslink to chain scission of the irradiated samples were studied and compared with those of unirradiated ones. In this S‐B‐S block copolymer, a relatively low‐radiation dose was found effective in improving the level of mechanical properties. Differential scanning calorimeter and dynamic mechanical analyzer were used to study the thermal characteristics of the irradiated polymer. Influence of a stabilizer at different concentrations on the properties of S‐B‐S at varied radiation doses were also focused on. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Hiding clinical information in medical images: an enhanced encrypted reversible data hiding algorithm grounded on hierarchical absolute moment block truncation coding

Multidimensional Systems and Signal Processing - Reversible data hiding in the encrypted domain has attracted a lot of consideration because of the necessity for content security and protection...     

Poly(vinyl chloride)–Acacia bark flour composite: Effect of particle size and filler content on mechanical,thermal, and morphological characteristics

This article describes the effect of filler [obtained from bark of Acacia (Babool)] content and its particle size (ranging from 100 to 150 μm and <50 μm) on the properties of poly(vinyl chloride) (PVC) composites. Bark of the fast‐growing species Acacia was used as powder for making PVC composites, which may find applications as a substitute to high‐cost wood and to avoid deforestation. A two‐roll mill was used for mixing varying amounts of bark flour with PVC formulation. Samples for testing were prepared by compression molding. Tensile strength and percentage of elongation at break decreased, whereas modulus increased with an increasing amount of bark flour. A significant increase in storage modulus (E′) was observed upon incorporation of filler. Improvement in properties was significant in the presence of filler, having a particle size <50 μm as compared to filler, having a particle size ranging from 100 to 150 μm. Morphological characterization was conducted by using scanning electron microscopy. A uniform dispersion of filler was observed in PVC matrix. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Chemical composition,functional properties and microstructural characteristics of three kabuli chickpea (Cicer arietinum L.) as affected by different cooking methods

Chickpea is an important food legume and is a major ingredient in many human diets. Chemical composition, physical parameters, functional properties and microstructural characteristics of three kabuli chickpea cultivars and the effects of three cooking methods were investigated. Carbohydrate and protein were two major components in all seeds. Cooking increased fibre, total carbohydrate and total and resistant starch contents, but decreased ash content. Protein and oil levels of the cooked samples either decreased or did not change significantly. Seed weight and density decreased with cooking. Hydration and swelling capacities as well as water absorption and holding capacities of cooked chickpeas were higher than raw samples, with the largest increases in the pressure‐cooked seeds. Seed weights were highly correlated with hydration (r = 0.89) and swelling (r = 0.76) rates. Emulsifying activity, emulsifying stability and foaming capacity of cooked chickpea flours decreased, while foaming stability increased. Chickpea flours had pronounced morphological changes after cooking.     

Influence of pigment blends of different shapes and size distributions on coated paper properties

Paper coating pigment plays an essential role in the achievement of the desired end paper qualities. Different pigment varieties are available for paper coating. Ground calcium carbonate (GCC) is the major one used frequently in coating formulations. Precipitated calcium carbonate (PCC) is gradually gaining importance in paper coating, as it can be prepared in different shapes and sizes. The present study was carried out to determine the influence of PCC pigments with different shapes and sizes on paper properties, and their limitations and advantages when blended with finer grade GCC. PCC pigments of calcite and aragonite crystalline polymorphs having rhombohedral, orthorhombic, and scalenohedral habits were selected for the study. It was observed that the viscosity and water-holding capacity of the coating color was reduced with the introduction of PCC in the coating formulation. The PCC pigments showed greater light scattering, opacity, and smoothness of the coated paper as compared to the GCC pigment. The clustered (rosette) shape of scalenohedral habit calcite PCC results in the greatest light scattering, opacity, and surface strength amongst all PCCs. The aragonite PCC of orthorhombic habit and calcite PCC of rhombohedral habit show an almost similar trend in coated paper properties with the greatest smoothness and paper gloss.     

Experimental and Numerical Characterization of the Influence of a Smoldering Cellulosic Substrate on a Cigarette’s Ignition Propensity Test

An experimental and numerical investigation was conducted to characterize the influence of the cellulosic substrate used to assess the ignition propensity (IP) of cigarettes. Such an IP test is currently prescribed by the ISO 12863 standard and its results typically show poor repeatability. It is believed that such a low reproducibility is mainly due to the variability of the cigarette itself but it is unclear as to what extent the substrate also influences the variability of the test results. Therefore, the objective of this investigation was to analyze the potential influence of the substrate by first characterizing the thermodynamic behavior experimentally and then constructing a numerical model that can quantify the relative influence of the distinct parameters. A suite of experimental methods that included TGA, DSC, infrared measurements and laser triangulation among others was used to measure the thermophysical properties of the substrate. These properties were then used to build a CFD model that simulated the smoldering combustion experienced by the substrate during the IP test. After validating the model against contactless temperature measurements, a parametric study consisting of 363 IP simulations was performed, which served to quantify the relative importance of 13 thermophysical parameters when varying in ranges of about 5%–50%. The results indicated that the heat capacity, pyrolysis activation energy, and air gap thickness are the most influencing aspects of the substrate because they influence the heat absorbed by the substrate about 7%, 26% and 33%, respectively. The latter parameter was found to significantly vary with each test and its influence was comparable to that of some major properties of the cigarette such as the cigarette’s temperature and burning rate. It is therefore postulated that the variability of the substrate itself plays an important role on the poor repeatability of the test and it may comprise its reliability.