Wavelet packet transform-based robust video watermarking technique

In this paper, a wavelet packet transform (WPT)-based robust video watermarking algorithm is proposed. A visible meaningful binary image is used as the watermark. First, sequent frames are extracted from the video clip. Then, WPT is applied on each frame and from each orientation one sub-band is selected based on block mean intensity value called robust sub-band. Watermark is embedded in the robust sub-bands based on the relationship between wavelet packet coefficient and its 8-neighbour (D ₈) coefficients considering the robustness and invisibility. Experimental results and comparison with existing algorithms show the robustness and the better performance of the proposed algorithm.     

Enhancing diamond drilling performance by the addition of non-ionic polymer to the flushing media

Drilling is a most important and crucial operation in the excavation industries.With the objective of looking into the enhancement of diamond drilling performance detailed laboratory investigations were carried out on phosphate rock.The effect of Poly (Ethylene Oxide) (PEO) added to the drilling water was studied by varying machine parameters and PEO concentration.The responses were rate of penetration and torque at the bit rock interface.Slake durability tests were also performed to understand the slaking behavior of phosphate rock in PEO solutions.     

Starch-stearic Acid Complex Development within Single and Twin Screw Extruders

Corn starch was extruded with 4% stearic acid in Brabender single screw and twin screw laboratory extruders. The screws were cooled and removed and samples were collected from locations along the screws. In the single screw extruder, starch gelatinization as determined by DSC and polarized light microscopy started in the compression zone and was completed in the metering zone. Starch-stearic acid complex formation as determined by iodine binding capacity and X-ray diffraction started at the same point as gelatinization and increased to a maximum near the tip of the screw. In the twin screw extruder, starch gelatinization and starch-stearic acid complex formation started at a distance of seven screw diameters and continued from there to the die end.     

Guided Waves on an Infinite Cylindrical Cavity in a Magneto-ionic Medium II. Dipolar Modes†

The characteristics of the guided waves supported by an infinitely long cylindrical cavity of free-space immersed in a magneto-ionic medium are investigated for the case of the magnetostatic field in the direction of the axis of the column. The dipolar case for which the fields have an exp (imφ) azimuthal variation, where φ is the angular variable and m ± 1, is treated. The characteristics of the transition, the resonance and the cut-off frequencies of the guided waves ore discussed with particular reference to their dependences on the radius of the free-space column. The dispersion characteristics under propagating conditions are studied in detail both for the special case of vanishing static magnetic field and for the general case of finite magneto-static field corresponding to the two typical values of the ratio R of the gyromagnetic to the plasma frequencies. The lowest-order mode is found to be of the modified TE type and has special features such as that it can have forward or backward wave and fast or slow wave regions in certain portions of its characteristics, depending on the radius of the free-Space column and the azimuthal variation of the fields. All the other higher-order modes are found to be fast forward waves, whose phase velocity monotonically decreases as the frequency is increased and approaches the free-space velocity of electromagnetic waves. For an extremely small radius of the free-space column, the group velocity is vanishingly small for a major portion of the range of propagation of the only existing, lowest-order surface wave.     

Electrochemical corrosion behaviours of Fe68Ni14-xMoxSi2B16 metallic glasses in 1N HCl and 1N H2SO4

Electrochemical corrosion behaviours of five Fe₆₈Ni_14-xMo_xSi₂B₁₆ glasses with x=0, 1, 2, 3 and 4 have been investigated in both 1 N HCl and 1 N H₂SO₄ solutions using potentiodynamic polarization and a.c. impedance spectroscopic techniques. The polarization and impedance results show that all the alloys possess inferior corrosion resistance which has been attributed to the low Ni content on one hand and the absence of passivators such as Cr and P on the other. Interestingly the alloys have been found to show weak passivation in more aggressive HCl and not in relatively mild H₂SO₄ solution. This has been explained in terms of dual behaviours of Mo in HCl and H₂SO₄ based on impedance data and literature work. The present study attempts to correlate impedance data with polarization data through the parameter polarization resistance and indicates that both values are comparable only when an alloy undergoes active dissolution and not when it exhibits passivity. This revised version was published online in November 2006 with corrections to the Cover Date.     

Molybdenum-induced enhancement of thermal stability of glassy Fe68Ni14−xMoxSi2B16 alloys

Abstracts are not published in this journal     

Nearest neighbour classification of Indian sign language gestures using kinect camera

People with speech disabilities communicate in sign language and therefore have trouble in mingling with the able-bodied. There is a need for an interpretation system which could act as a bridge between them and those who do not know their sign language. A functional unobtrusive Indian sign language recognition system was implemented and tested on real world data. A vocabulary of 140 symbols was collected using 18 subjects, totalling 5041 images. The vocabulary consisted mostly of two-handed signs which were drawn from a wide repertoire of words of technical and daily-use origins. The system was implemented using Microsoft Kinect which enables surrounding light conditions and object colour to have negligible effect on the efficiency of the system. The system proposes a method for a novel, low-cost and easy-to-use application, for Indian Sign Language recognition, using the Microsoft Kinect camera. In the fingerspelling category of our dataset, we achieved above 90% recognition rates for 13 signs and 100% recognition for 3 signs with overall 16 distinct alphabets (A, B, D, E, F, G, H, K, P, R, T, U, W, X, Y, Z) recognised with an average accuracy rate of 90.68%.