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Performance Comparison: Optical and Magnetic Head Tracking
No full textTracking also called Position and Orientation Tracking or Position Tracking and mapping, is used in VEs where the orientation and the position of a real physical object is required. Specifying a point in 3-D requires the transition position, that is the Cartesian coordinates x, y, and z. However, many VE applications manipulate entire objects and this requires the orientation to be specified by three angles known as pitch (elevation), roll, and yaw (azimuth). Thus, six degrees of freedom (DOF) are the minimum required to fully describe the position of an object in 3-D.
Head tracking is basically related to the head movements and is used for updating the head moves. They provide accurate provide information to the flight computer about the orientation of the head of the pilot with high degree of accuracy and extremely low impact on helmet mounted display (HMD) weight, size, and packaging. This paper compares the performance of head tracking utilizing optical and magnetic tracking techniques
EDF-Based Edge-Filter Interrogation Scheme for FBG Sensors
No full textA fiber Bragg grating (FBG) sensor employing an interrogation scheme based on erbium-doped fiber (EDF) edge detection filter, with enhanced detection bandwidth and intrinsic temperature insensitivity, is proposed and experimentally demonstrated. The edge filter is based on the spectral dependence of absorption in EDF with the possibility of tailoring the absorption profile using appropriate lengths of EDF. A wide filter bandwidth of about 10 nm and a slope detection sensitivity of 1.0 dB/nm in the C-band is demonstrated and validated by simulation results. The proposed scheme is versatile and allows for simultaneous interrogation of multiple FBGs
Sol–gel based composite of gold nanoparticles as matix for tyrosinase for amperometric catechol biosensor
No full textComposite of sol–gel and PVP stabilized gold nanoparticles has been synthesized chemically and is used as an immobilization matrix for tyrosinase enzyme. The composite was spin coated on ITO electrode which was then characterized for its optical and electrochemical behavior. Cyclic voltametric study of ITO/Sol–AuNPs composite electrode showed well defined redox couple for Fe+ ions which is due to high electro-conductivity supplied mainly by gold nanoparticle coverage. The capacitance and faradic current are found to be 6.0 × 10−5 mF and 3.172 × 10−4 A respectively. The analytical performance of composite based catechol biosensor has been evaluated as a function of catechol concentration, buffer concentration and buffer pH. The system showed linearity from 1.0 × 10−6 M to 6 × 10−6 M with sensitivity of 0.01 A/M and LOD as 3 × 10−7 M. Effect of presence of gallic acid, catechin and cresol have been studied using amperometry which showed that these species does not interfere with catechol estimation
Fast response time alcohol gas sensor using nanocrystalline F-doped SnO2 films derived via sol–gel method
No full textPure and fluorine-modified tin oxide (SnO2) thin films (250–300 nm) were uniformly deposited on corning glass substrate using sol–gel technique to fabricate SnO2-based resistive sensors for ethanol detection. The characteristic properties of the multicoatings have been investigated, including their electrical conductivity and optical transparency in visible IR range. Pure SnO2 films exhibited a visible transmission of 90% compared with F-doped films (80% for low doping and 60% for high doping). F-doped SnO2 films exhibited lower resistivity (0· 12 × 10 − 4 Ω cm) compared with the pure (14·16 × 10 − 4 Ω cm) one. X-ray diffraction and scanning electron microscopy techniques were used to analyse the structure and surface morphology of the prepared films. Resistance change was studied at different temperatures (523–623 K) with metallic contacts of silver in air and in presence of different ethanol vapour concentrations. Comparative gas-sensing results revealed that the prepared F-doped SnO2 sensor exhibited the lowest response and recovery times of 10 and 13 s, respectively whereas that of pure SnO2 gas sensor, 32 and 65 s, respectively. The maximum sensitivities of both gas sensors were obtained at 623 K
An experimental study on the effect of magneto-rheological finishing on diamond turned surfaces
No full textMagneto-rheological materials are a class of smart materials whose rheological properties can be rapidly varied by applying a magnetic field. Magneto-rheological finishing utilizes magneto-rheological fluid, which consists of magnetic particles, non-magnetic abrasives and some additives in water or other carrier to polish the materials. Single-point diamond turning is able to remove hundreds of microns of material and generate surface with micron accuracies. Residual turning marks are the most important factor limiting the performance in diamond turning process. Magneto-rheological finishing has inherent ability to improve micro-roughness, remove subsurface damage and reduce residual stresses induced during diamond turning process. Combining single-point diamond turning and magneto-rheological finishing creates a deterministic process for manufacturing highly finished surfaces. In this article, an attempt has been made to improve the finish of diamond turned surface with magneto-rheological finishing and to investigate the effects of parameters like current, spacing, wheel speed, feed rate and magnetic field on the final surface finish. Based on the parametric study, an optimum combination of process parameters is identified using analysis of variance. Various image processing techniques have been used for the comparison of the surface analysis of diamond turned surfaces and the magneto-rheological finished surfaces
Computer Aided Malarial Diagnosis for JSB Stained White Light Images Using Neural Networks
No full textThis paper focuses on development of sensitive malarial detection system for images of (JSB) stained thick
blood slides acquired from conventional light microscopes. Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected mosquitoes. Light microscopy enables the visualization of malarial parasites in a thick or thin smear of the patient’s blood. Automation of the evaluation process in the diagnosis of malaria is of high importance. The proposed system describes the computerized method of image analysis
involving three main phases: pre-processing, where the images are corrected for luminance and transformed to a
constant color space. A histogram based image segmentation processing where the maximum artefacts and over stained objects are avoided. Finally, Feature extraction along with a multi-layer, feedforward, backpropagation neural network was employed for classifying the objects as parasite/wbc. The proposed method achieves the 91% of sensitivity, 85% of specificity with positive prediction rate 88%
Optimization of spray parameters in the fabrication of SnO2 layers using electrostatic assisted deposition technique
No full textTin oxide (SnO2) thin films for gas sensing applications were prepared using electrostatic spray deposition method under optimum deposition conditions. It is shown in the paper that desired film morphology can be obtained by controlling different spray parameters (liquid properties, applied voltage, nozzle-substrate distance and substrate temperature). The spray parameters were optimized with respect to droplet diameter and applied voltage. An empirical relationship between critical voltage and different spray parameters was established for optimization. The morphology of the films prepared using these optimized spray parameters were investigated using X-Ray Diffraction (XRD) and Scanning Electron Microscope SEM)
Study on reflectivity and photostability of Al-doped TiO2 nanoparticles and their reflectors
No full textThe effect of Al doping on the reflective properties of TiO2 nanoparticles, synthesized by sol-gel method, has been investigated. It has been observed that with Al doping, the phase transition temperature for anatase to rutile phase increases; however, no change in morphology has been observed. No additional absorption edge was found in the absorption spectra, but a weak luminescent peak was noticed in the photoluminescence spectra. TiO2 nanoparticles with 0.1% Al doping show higher photostability with practically no change in reflectance. A coating material has been prepared by dispersing these synthesized nanoparticles in water solution of organic binder. Coating material parameters such as pigment to binder weight ratio, solvent ratio, pH of solution have been taken into care to make the coating material flowable with good ability to adhere. Their coating was applied on a plastic substrate with different coating thicknesses to design light reflectors. These reflectors have been found to have diffuse reflectance of 98.17-98.29% for the 0.25-mm-thick coating
Particle Swarm Optimization (PSO) based Tool Position Error Optimization
Get PDFHigh-precision tool positioning is one of the fundamental
requirements for the industry now-a-days. Earlier, tool
positioning and its verification were done using sensors
etc. In this paper, an algorithm has been proposed to
increase the tool positioning accuracy by analyzing the
information obtained using CCD camera. The images of
lathe tool are used for carrying out the
experiments. Firstly, the images of lathe tool, before and
after movement, are captured. From these images, the
distance traversed by the tool is calculated which is the
observed distance. Tool positioning can be achieved
accurately if the errors arising out of target (distance
expected to be traversed by the tool) and observed position
of the tool are optimized. This paper addresses positional
errors and presents an error optimization method using
arithmetic measures such as mean, median and Particle
Swarm Optimization (PSO) based nature-inspired
technique. Finally, the results of the two arithmetic
measures are compared with the results of PSO which
shows the capability of PSO to converge towards the
optimal solutio
Classification of tea grains based upon image texture feature analysis under different illumination conditions
No full textThis paper discusses the role of illumination in discrimination of tea samples based upon textural features of tea granules. The images of tea granules were acquired using 3CCD color camera under Dual Ring light which consists of both Darkfield as well as Brightfield type of illumination. Ten graded tea samples were analyzed. Five textural features were ‘entropy’, ‘contrast’, ‘homogeneity’, ‘correlation’ and ‘energy’ obtained under both illuminations. The acquired textural features were subjected to principal component analysis (PCA). The results showed that best discrimination was obtained with Darkfield illumination with a variance of 96% whereas Brightfield illumination showed low discrimination with only 83% variance. Analysis of PCA biplot indicated correlations among graded tea samples and textural features. The study concludes that textural features may be used to estimate tea quality under Darkfield illumination being non-destructive and quick technique