Cross spectral iris recognition for surveillance based applications

Multimedia Tools and Applications - Human iris has been explored as one of the most promising biometric traits since last many years. This paper presents a new ingenious feature extraction approach...     

Properties determining choice of mother wavelet

Properties of wavelets with finite as well as infinite support are summarised to facilitate mother wavelet selection in a chosen application. The quantitative guidelines reduce dependence on trial-and-error schemes resorted to for selection and underscore the importance of such selection in any application of interest. In wavelet-based image sequence superresolution, studied during the last four years, the use of a B-spline mother wavelet is justified.     

Biparietal diameter: a useful measure for determining gestational age of human abortuses

BACKGROUND: The crown-rump length is conventionally used to determine the age of human abortuses. However, it is not reliable as it is dependent on the positioning of the conceptus. We compared this with the biparietal diameter and foot length for determining the gestational age. METHODS: Different measurements, commonly used to assess gestational age, were measured in 146 human abortuses for which an accurate obstetric history could not be elicited. Measurements taken were crown-rump length, biparietal diameter and foot length. These were correlated with the observations at antenatal examinations before finalizing the approximate age. RESULTS: Multiple regression analysis of the data indicated that of the three measurements, the biparietal diameter was the most reliable for determining foetal gestational age between 8 and 26 weeks. The age determined with the biparietal diameter correlated well with that of abortuses with an accurate obstetric history. CONCLUSION: The biparietal diameter of a human foetus may be used to determine its age if the obstetric history regarding the period of gestation is vague or not available.     

An efficient new method for the detection of QRS in electrocardiogram

A simple and efficient new method for QRS detection in Electrocardiogram (ECG) is proposed in this paper. Initially data is preprocessed using two stage median filter for removing baseline drift. The second stage enhances the peaks of ECG wave components by using sixth power of signal. The next stage identifies the QRS complex by taking a variable window size. The detection sensitivity (Se) and positive predictivity (+P) of CSE (Common Standards for Quantitative Electrocardiography) measurement database, MIT/BIH (Massachusetts Institute of Technology/Beth Israel Hospital) Arrhythmia database, European ST-T database and QT database are Se 99.51 & +P 99.69%, Se 99.21 & +P 99.34%, Se 99.53 & +P 99.72% and Se 99.87 & +P 99.95% respectively. These four standard databases used to perform QRS detection considered 368 cases, tested 1,006,168 beats and achieved overall average sensitivity 99.52% and positive predictivity 99.69%. The MIT/BIH Noise Stress Test Database also tested by proposed method.     

Dielectric Properties of the "Twinned" 8H-Hexagonal Perovskite Ba8Nb4Ti3O24

The dielectric properties of dense ceramics of the "twinned" 8H-hexagonal perovskite Ba₈Nb₄Ti₃O₂₄ are reported. Single-phase powders were obtained from the mixed-oxide route at 1325°C and ceramics (>92% of the theoretical X-ray density) by sintering in air or flowing O₂ at 1400°–1450°C. The ceramics are dc insulators with a band gap >3.4 eV that resonate at microwave frequencies with relative permittivity, ɛ_r∼44–48, quality factor, Q × f _r∼21 000–23 500 GHz (at f _r∼5.5 GHz) and temperature coefficient of resonant frequency, TC _f,∼+115 ppm/K.     

Iodine-loaded poly(silicic acid) gellan nanocomposite mucoadhesive film for antibacterial application

Iodine-loaded poly(silicic acid) gellan nanocomposite film was fabricated and evaluated for antibacterial properties. Poly(silicic acid) nanoparticles were synthesized by condensation of silicic acid under alkaline conditions in the presence of polyvinyl pyrrolidone, phosphate ions, and molecular iodine. The nanoparticles were incorporated into gellan dispersion to prepare gellan nanocomposite film using the solvent casting method. The nanocomposite films were characterized by Fourier transformed infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction studies. The results of characterization studies indicated improved thermal stability and an increase in the degree of crystallinity. The scanning electron micrographs and energy dispersive X-ray spectrum confirmed the uniform dispersion of silica and iodine in the nanocomposite films. The analysis of physical and mechanical properties revealed the enhanced tensile strength, moisture resistance, and higher folding endurance of poly(silicic acid) gellan nanocomposite films as compared to gellan film. Further, the iodine-loaded poly(silicic acid) gellan nanocomposite films showed good antibacterial activity against Staphylococcus aureus and Escherichia coli and effective mucoadhesive strength. The results indicate that iodine-loaded poly(silicic acid) gellan nanocomposite mucoadhesive film can be used for potential antibacterial applications in pharmaceuticals.     

Region-Based Hierarchical Image Matching

This paper presents an approach to region-based hierarchical image matching, where, given two images, the goal is to identify the largest part in image 1 and its match in image 2 having the maximum similarity measure defined in terms of geometric and photometric properties of regions (e.g., area, boundary shape, and color), as well as region topology (e.g., recursive embedding of regions). To this end, each image is represented by a tree of recursively embedded regions, obtained by a multiscale segmentation algorithm. This allows us to pose image matching as the tree matching problem. To overcome imaging noise, one-to-one, many-to-one, and many-to-many node correspondences are allowed. The trees are first augmented with new nodes generated by merging adjacent sibling nodes, which produces directed acyclic graphs (DAGs). Then, transitive closures of the DAGs are constructed, and the tree matching problem reformulated as finding a bijection between the two transitive closures on DAGs, while preserving the connectivity and ancestor-descendant relationships of the original trees. The proposed approach is validated on real images showing similar objects, captured under different types of noise, including differences in lighting conditions, scales, or viewpoints, amidst limited occlusion and clutter.     

Mirror uncertainty and uniqueness conditions for determining shape and motion from orthographic projection

This paper presents new forms of necessary and sufficient conditions for determining shape and motion to within a mirror uncertainty from monocular orthographic projections of any number of point trajectories over any number of views. The new forms of conditions use image data only and can therefore be employed in any practical algorithms for shape and motion estimation. We prove that the mirror uncertainty for the three view problem also exists for a long sequence: if shapeS is a solution, so is its mirror imageS which is symmetric toS about the image plane. The necessary and sufficient conditions for determining the two sets of solutions are associated with the rank of the measurement matrixW.If the rank ofW is 3, then the original 3D scene points cannot be coplanar and the shape and motion can be determined to within a mirror uncertainty from the image data if and only if there are three distinct views. This condition is different from Ullman's theorem (which states thatthree distinct views of four noncoplanar points suffice to determine the shape and motion up to a reflection) in two aspects: (1) it is expressed in terms of image data; (2) it applies to a long image sequence in a homogeneous way.If the rank ofW is 2 and the image points in at least one view are not colinear in the image plane, then there are two possibilities: either the motion is around the optical axis, or the 3-D points all lie on the same plane. In the first case, the motion can be determined uniquely but the shape is not determined. In the second case, a necessary and sufficient condition is to be satisfied and at least 3 point trajectories over at least 3 distinct views are needed to determine the shape in each view to within a mirror uncertainty, and the number of motion solutions is equal to the combinatorial number of the possible positions of the plane in different views. The necessary and sufficient condition is associated with the rank of a matrixC: ifC has a rank of 1, the plane is undetermined; ifC has a rank of 2 (implying there are exactly 3 distinct views), then a necessary and sufficient condition, whose physical meaning is not completely clear, is to be satisfied to determine the plane to within 2 sets; ifC has a rank of 3 (implying there are 4 or more distinct views), then the plane can always be determined to within two sets.If the rank ofW is 2 or 1 and the image points in each view are colinear in the image plane, then the three dimensional motion problem reduces to a two dimensional motion problem. In this case, the uniqueness condition is associated with the rank of the reduced measurement matrix . If has a rank of 2, then the original 3D points cannot be colinear in the space and the shape and motion can be determined to within two sets if and only if three or more views are distinct. If has a rank of 1, there are two possibilities: if the rows of are identical, then either the original 3D points are not colinear and the motion is zero, or the points are colinear and possibly move between two mirror symmetric positions; if the rows of are not identical, then the motion is not determined.All proofs are constructive and thus define an algorithm for determining the uniqueness of solution as well as for estimating shape and motion from point trajectories.