Literature review of image compression effects on face recognition

In this research work, a literature review is conducted to assess the progress made in the field of image compression effects on the face recognition. The DCT algorithms are considered for the review and their application is limited only to JPEG compression. In this review, progress made in the DCT algorithms of a single image, and a series images from a video, namely 2D DCT and 3D DCT respectively, along with several other algorithms in the application of face recognition are discussed in detail.&nbsp

Mixed Phase in Compact Starts : M-R relations and radial oscillations

It is believed that quark stars or neutron stars with mixed phase in the core have smaller radii compared to ordinary compact stars. With the recent observation of several low radius objects, typically a radius of $<10 Km.$ for star of mass $< 1M_0$ in low mass X-ray binaries (LMXB), it has become very important to understand the nature of these objects. An accurate determination of mass-radius relationship of these objects provide us with a physical laboratory to study the composition of high density matter and the nature of phase transition. We study the effect of quark and nuclear matter mixed phase on mass radius relationship and radial oscillations of neutron stars. We find that the effect of the mixed phase is to decrease the maximum mass of a stable neutron star and to decrease the radial frequencies .Comment: guest contribution at Int. Workshop on Astronomy & Relativistic Astrophysics (IWARA 03)held at Olinda-PE (Brazil) from Oct. 12-17,200

Paramagnetic nematic liquid crystals

Five nematogenic complexes, bis[1-(p-n-decyl-biphenyl) 3-(p-substituted phenyl) propane-1, 3-dionato]-copper (II), have been prepared. The mesophase, which occurs monotropically in all of them, is of the usual nematic type, but has paramagnetic properties. Magnetic, dielectric and electron paramagnetic resonance measurements are presented. A preliminary analysis of the data indicates the existence of antiparallel correlations in the nematic phase

Scattering of Dirac Waves off Kerr Black Holes

Chandrasekhar separated the Dirac equation for spinning and massive particles in Kerr geometry into radial and angular parts. Here we solve the complete wave equation and find out how the Dirac wave scatters off Kerr black holes. The eigenfunctions, eigenvalues and reflection and transmission co-efficients are computed. We compare the solutions with several parameters to show how a spinning black hole distinguishes mass and energy of incoming waves. Very close to the horizon the solutions become independent of the particle parameters indicating an universality of the behaviour.Comment: 12 Latex pages and 7 Figures; MNRAS style; Accepted for Publication in MNRA

Dynamics of electromagnetic waves in Kerr geometry

Here we are interested to study the spin-1 particle i.e., electro-magnetic wave in curved space-time, say around black hole. After separating the equations into radial and angular parts, writing them according to the black hole geometry, say, Kerr black hole we solve them analytically. Finally we produce complete solution of the spin-1 particles around a rotating black hole namely in Kerr geometry. Obviously there is coupling between spin of the electro-magnetic wave and that of black hole when particles propagate in that space-time. So the solution will be depending on that coupling strength. This solution may be useful to study different other problems where the analytical results are needed. Also the results may be useful in some astrophysical contexts.Comment: 15 Latex pages, 4 Figures; Accepted for publication in Classical and Quantum Gravit

A NEW STABILITY INDICATING UPLC METHOD DEVELOPMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF METOLAZONE AND SPIRONOLACTONE IN BULK AND IN ITS PHARMACEUTICAL FORMULATIONS

Objective: The objective of the work is to develop and validate a new, simple, highly sensitive RP-UPLC method for simultaneous estimation of Metolazone and Spironolactone in bulk and in its dosage forms. Methods: The method was developed on a reversed-phase Hypersil Gold C18 (2.1× 100 mm, 2.7 µm) column with isocratic elution. Detection was done by UV-Spectroscopy at a detection wavelength of 235 nm. The analytical procedure was validated by assessing the specificity, linearity, precision, accuracy, limit of detection, limit of quantification, robustness and ruggedness as per ICH guidelines. Results: The results were obtained as follows- the retention times were found to be around 2.888 min and 3.835 min, the percentage purity was observed to be 99 % w/v and 100 % w/v, the percentage recovery was found to be 99.90% and 99.9% respectively for Metolazone and Spironolactone. Calibration plots were linear (r2 &gt; 0.999) over the concentration range of 12 to 28μg/ml for Metolazolone and 120 to 280μg/ml for Spironolactone. The LOD was 0.0002µg/ml for Metolazone and 0.01µg/ml for Spironolactone. The LOQ was found to be 0.0008µg/ml for Metolazone and 0.003µg/ml for Spironolactone. Conclusion: The developed analytical method for the simultaneous quantitation of Metolazone and Spironolactone was found to be specific, rapid, reliable, and reproducible. No interference from any component of pharmaceutical dosage form was observed. The method is amenable to the routine analysis of large numbers of samples with good precision and accuracy

Trapped gravitational wave modes in stars with R>3M

The possibility of trapped modes of gravitational waves appearing in stars with R>3M is considered. It is shown that the restriction to R<3M in previous studies of trapped modes, using uniform density models, is not essential. Scattering potentials are computed for another family of analytic stellar models showing the appearance of a deep potential well for one model with R>3M. However, the provided example is unstable, although it has a more realistic equation of state in the sense that the sound velocity is finite. On the other hand it is also shown that for some stable models belonging to the same family but having R<3M, the well is significantly deeper than that of the uniform density stars. Whether there are physically realistic equations of state which allow stable configurations with trapped modes therefore remains an open problem.Comment: 10 pages, 3 figures, LaTeX2

Power laws, scale invariance, and generalized Frobenius series: Applications to Newtonian and TOV stars near criticality

We present a self-contained formalism for analyzing scale invariant differential equations. We first cast the scale invariant model into its equidimensional and autonomous forms, find its fixed points, and then obtain power-law background solutions. After linearizing about these fixed points, we find a second linearized solution, which provides a distinct collection of power laws characterizing the deviations from the fixed point. We prove that generically there will be a region surrounding the fixed point in which the complete general solution can be represented as a generalized Frobenius-like power series with exponents that are integer multiples of the exponents arising in the linearized problem. This Frobenius-like series can be viewed as a variant of Liapunov's expansion theorem. As specific examples we apply these ideas to Newtonian and relativistic isothermal stars and demonstrate (both numerically and analytically) that the solution exhibits oscillatory power-law behaviour as the star approaches the point of collapse. These series solutions extend classical results. (Lane, Emden, and Chandrasekhar in the Newtonian case; Harrison, Thorne, Wakano, and Wheeler in the relativistic case.) We also indicate how to extend these ideas to situations where fixed points may not exist -- either due to ``monotone'' flow or due to the presence of limit cycles. Monotone flow generically leads to logarithmic deviations from scaling, while limit cycles generally lead to discrete self-similar solutions.Comment: 35 pages; IJMPA style fil