122 research outputs found
Human Face Recognition and Detection
Human face detection and recognition play important roles in many applications such as video surveillance and face image database management. In our project, we have studied worked on both face recognition and detection techniques and developed algorithms for them. In face recognition the algorithm used is PCA (principal component analysis), MPCA(Multilinear Principal Component Analysis) and LDA(Linear Discriminant Analysis) in which we recognize an unknown test image by comparing it with the known training images stored in the database as well as give information regarding the person recognized. These techniques works well under robust conditions like complex background, different face positions. These algorithms give different rates of accuracy under different conditions as experimentally observed.
In face detection, we have developed an algorithm that can detect human faces from an image. We have taken skin colour as a tool for detection. This technique works well for Indian faces which have a specific complexion varying under certain range. We have taken real life examples and simulated the algorithms in MATLAB successfully
Dynamic Characteristics of Drop-substrate Interactions in Direct Ceramic Ink-jet Printing using High Speed Imaging System
Solid freeform fabrication has the potential to construct ceramic parts, directly from computer aided design (CAD) data, without a mould or a die by the addition of material. Direct ceramic ink-jet printing is one of the techniques used in freeform fabrication. Ceramic tiles used in space vehicles can be produced by this method wherein a porous ceramic substrate (Al2O3/SiC) can be filled with a ceramic ink and processed subsequently. The success of this process depends on the systematic preparation of ceramic inks and the deposition of the ceramic ink on the substrate. In this paper, photographic studies were made on the characteristics of ceramic ink droplets when these are deposited on a porous ceramic substrate from a burette under gravity. For this investigation, ceramic inks were prepared using different amounts (0.253.0 vol. %) of an organic dispersant (oleic acid) added to a ceramic composition containing different amounts: (a) (7.5 17.5 vol. %) of alumina and (b) (7.515.0 vol. %) of zirconia with ethyl alcohol as a carrier. From this study, the drop formation, sedimentation in the drop, spread of drop on the substrate, splashing of drop impinging a previous ceramic ink layer on the substrate, and merging of droplets after deposition, are observed. This method is useful for manufacturing of parts with ceramic fibres filled with ceramic particles and this study can provide inner details on the behaviour of ink drops.Defence Science Journal, 2009, 59(6), pp.675-682, DOI:http://dx.doi.org/10.14429/dsj.59.157
Original Article
Phosphodiesterase specific for the hydrolysis of diphenylphosphate, one of aromatic phosphodiesters, was obtained from hog kidney by following procedure. To hog kidney homogenized in a Waring blendor with 3 volumes of distilled water was added solid sodium chloride to a final concentration of 1% and after adjusting of pH to 5 with ca. 5 N hydrochloric acid, it was shaken for 10 minutes with an equal volume of n-butanol, allowed to stand for one hour, and centrifuged. The aqueous extract present beneath the floating gel layer of protein and butanol mixture, was siphoned out and fractionated with ammonium sulfate. The precipitate obtained between 45 and 70 % saturation was dissolved in a small volume of distilled water, dialyzed for 48 hours against running tap water, and then, to inactivate the monoesterase, heated in water bath of 100° for 5 minutes, whereby the solution became faintly turbid. The enzyme solution, thus prepared, hydrolyzed diphenylphosphate, liberating phenol but no inorganic phosphate, while it was inactive to monophenylphosphate. Diphenylphosphate of a final concentration of 0.0005M could be hydrolyzed in one hour at the optimum pH 7 to the extent of 40%. At this pH, the enzyme activity was not influenced by addition of Mg^, Ca^, or CN^. Bis-dichloroisopropylphosphate, dibenzylphosphate, diethylphosphate, lysolecithin, RNA, and DNA were resistant to this enzyme. It is conceivable that these diesters are hydrolyzed by other enzymes different from the aromatic phosphodiesterase, presented in this paper
Antioxidant Properties of the Methanol Extract of the Wood and Pericarp of Caesalpinia decapetala
The antioxidant activities of the methanol extracts from the wood and pericarp of Caesalpinia decapetala (Roth) Alston (Caesalpiniaceae) were assessed in efforts to validate the herb. The antioxidant activity of the plant has been studied using its ability to scavenger DPPH, superoxide radicals, and nitric oxide radical along with its ability to inhibit lipid peroxidation. The antioxidant activity and phenolic content of the pericarp as determined by the DPPH, superoxide radical, nitric oxide radical, total phenols, the flavonoids, and total flavonols were higher than that of the wood. Analysis of plant extracts revealed a high amount of polyphenols and flavonoids suggesting a possible role of these phytoconstituents in the antioxidant property. Moreover, the results were observed in a concentration and dose dependent manner. Studies clearly indicate that the C. decapetala has significant antioxidant activity
Amplitude measurements of Faraday waves
A light reflection technique is used to measure quantitatively the surface
elevation of Faraday waves. The performed measurements cover a wide parameter
range of driving frequencies and sample viscosities. In the capillary wave
regime the bifurcation diagrams exhibit a frequency independent scaling
proportional to the wavelength. We also provide numerical simulations of the
full Navier-Stokes equations, which are in quantitative agreement up to
supercritical drive amplitudes of 20%. The validity of an existing perturbation
analysis is found to be limited to 2.5% overcriticaly.Comment: 7 figure
Quick chip assay using locked nucleic acid modified epithelial cell adhesion molecule and nucleolin aptamers for the capture of circulating tumor cells
The role of circulating tumor cells (CTCs) in disease diagnosis, prognosis, monitoring of the therapeutic efficacy, and clinical decision making is immense and has attracted tremendous focus in the last decade. We designed and fabricated simple, flat channel microfluidic devices polydimethylsiloxane (PDMS based) functionalized with locked nucleic acid (LNA) modified aptamers (targeting epithelial cell adhesion molecule (EpCAM) and nucleolin expression) for quick and efficient capture of CTCs and cancer cells. With optimized flow rates (10 μl/min), it was revealed that the aptamer modified devices offered reusability for up to six times while retaining optimal capture efficiency (>90%) and specificity. High capture sensitivity (92%) and specificity (100%) was observed in whole blood samples spiked with Caco-2 cells (10-100 cells/ml). Analysis of blood samples obtained from 25 head and neck cancer patients on the EpCAM LNA aptamer functionalized chip revealed that an average count of 5 ± 3 CTCs/ml of blood were captured from 22/25 samples (88%). EpCAM intracellular domain (EpICD) immunohistochemistry on 9 oral squamous cell carcinomas showed the EpICD positivity in the tumor cells, confirming the EpCAM expression in CTCs from head and neck cancers. These microfluidic devices also maintained viability for in vitro culture and characterization. Use of LNA modified aptamers provided added benefits in terms of cost effectiveness due to increased reusability and sustainability of the devices. Our results present a robust, quick, and efficient CTC capture platform with the use of simple PDMS based devices that are easy to fabricate at low cost and have an immense potential in cancer diagnosis, prognosis, and therapeutic planning
Nonlinear Measures for Characterizing Rough Surface Morphologies
We develop a new approach to characterizing the morphology of rough surfaces
based on the analysis of the scaling properties of contour loops, i.e. loops of
constant height. Given a height profile of the surface we perform independent
measurements of the fractal dimension of contour loops, and the exponent that
characterizes their size distribution. Scaling formulas are derived and used to
relate these two geometrical exponents to the roughness exponent of a
self-affine surface, thus providing independent measurements of this important
quantity. Furthermore, we define the scale dependent curvature and demonstrate
that by measuring its third moment departures of the height fluctuations from
Gaussian behavior can be ascertained. These nonlinear measures are used to
characterize the morphology of computer generated Gaussian rough surfaces,
surfaces obtained in numerical simulations of a simple growth model, and
surfaces observed by scanning-tunneling-microscopes. For experimentally
realized surfaces the self-affine scaling is cut off by a correlation length,
and we generalize our theory of contour loops to take this into account.Comment: 39 pages and 18 figures included; comments to
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