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Synthesis and Optical Characterization of ZnO Quantum Dots and Nanorods
No full textZnO quantum dots were synthesized via precipitation using millimolar solutions of zinc acetate and sodium hydroxide in methanol. The synthesized quantum dots were characterized via absorption and fluorescence measurements. The onset of absorption observed at a lower wavelength of ∼350 nm as compared to bulk (380 nm) indicates an increase in the band gap through quantum confinement and confirms the presence of quantum dots. In order to calculate the size and distribution of ZnO quantum dots, fluorescence measurements were made. The synthesized quantum dots were drop casted on gold coated silicon substrates and were used as seeds to grow nanorods by using aqueous solutions of zinc nitrate (hexahydrate) and hexamine. The FESEM micrographs revealed good quality hexagonal shaped nanorods with a relatively uniform diameter of ∼75 nm
Mechanical Splicing of Hollow Core Photonic Crystal Fiber with Single Mode Fiber for Gas Sensing
No full textPrecision Mechanical Splicing of Hollow Core Photonic Crystal Fiber (HC-PCF) with Single Mode Fiber (SMF) is a challenge due to different numerical aperture (NA), core diameter and mode field diameter (MFD) of these two fibers. Presently, controlled arc fusion splicing technique is used to permanently splice these two fibers but this technique leads to losses due to PCF air hole collapse making it unsuitable for gas sensing applications. The results of new technique for mechanical splicing of PCF and SMF fibers with gap adjustments and known defined optical power coupling, without PCF air hole collapse is presented in this paper and these results will be helpful in remote PCF gas sensor design
Avionic Cockpit Display Systems
No full textStrategic sector is a highly guarded area imposed with technology denial putting a challenge on indigenous developments and bring it to par-excellence. A challenge was placed in the eighties to CSIR-CSIO to develop indigenous instruments for defense sector. 70mm Aerial Panoramic Camera
for MIG21Aircraft to capture aerial pictures, Projection plotter with range bearing graticules for Kamorta class of ships for Navy were major efforts in this direction. Subsequently another big challenge was put up to CSIO to enter into state-of-art technology for avionic cockpit display systems (Head Up Display (HUD)) for Light Combat Aircraft (LCA) and Hindustan Jet Trainer (HJT36) aircraft. This system allows to display the flight information of several selectable modes in collimated form so that the pilot can view this information superimposed on his view of the outside world without having to change his line of sight or visual accommodation
Impedance Study of Drinking Water and Tastants Using Conducting Polymer and Metal Electrodes
No full textIn this study the sensing capabilities of a combination
of metals and conducting polymer electrodes for drinking water and dissolved tastants using an AC-impedance mode in
frequency range 102 to 105 Hz at 0.1 V potential has been carried out. Classification of seven different bottled and municipal drinking water samples along with various tastants dissolved in DI water (DI water) for KCl (5mM) (salty), HCl (5 mM) (sour) quinine (0.1 mM) (bitter), sucrose (5 mM) (sweet), black tea liquor, black tea liquor with sucrose (2% sugar solution), and a bottle of “packed” orange juice has been made using six different working electrodes in a multi electrode setup using PCA. Working electrodes of Platinum (Pt), Gold (Au), Silver (Ag), Glassy Carbon (GC) and conducting polymer electrodes of Polyaniline (PANI) and Polypyrrole (PPY) grown on an ITO surface potentiostatically have been deployed in a three electrode set up. The impedance response of these water samples using number of working electrodes shows a decrease in the real and
imaginary impedance values presented on nyquist plots
depending upon the nature of the electrode and amount of
dissolved salts present in water/tastants. The different sensing surfaces allowed a high cross-selectivity in response to the same analyte. From PCA plots it was possible to classify drinking water in 3-4 classes using conducting polymer electrodes; however tastants were well separated from the PCA plots employing the impedance data of both conducting polymer and metal electrodes
Enhancing electronic nose performance: A novel feature selection approach using dynamic social impact theory and moving window time slicing for classification of Kangra orthodox black tea (Camellia sinensis (L.) O. Kuntze)
No full textThis paper presents a novel multiobjective wrapper approach using dynamic social impact theory based optimizer (SITO) and moving window time slicing (MWTS) for the performance enhancement of an electronic nose (EN). SITO, in conjunction with principal component analysis (PCA) and support vector machines (SVMs) classifier, has been used for the classification of samples collected from the single batch production of Kangra orthodox black tea (Camellia sinensis (L.) O. Kuntze). The work employs a novel SITO assisted MWTS (SITO-MWTS) technique for identifying the optimum time intervals of the EN sensor array response, which give the maximum classification rate. Results show that, by identifying the optimum time slicing window positions for each sensor response, the performance of an EN can be improved. Also, the sensor response variability is time dependent in a sniffing cycle, and hence good classification can be obtained by selecting different time intervals for different sensors. The proposed method has also been compared with other established techniques for EN feature extraction. The work not only demonstrates the efficacy of SITO for feature selection owing to its simplicity in terms of few control parameters, but also the capability of an EN to differentiate Kangra orthodox black tea samples at different production stages
Design of an assistive anaesthesia drug delivery control using knowledge based systems
No full textManual methods used during anaesthesia, to decide and deliver the quantity of drug, required significant effort from the clinical standpoint not guaranteeing an optimal performance. Delivering adequate anaesthesia requires precise automation in anaesthesia drug delivery system which will improve the patient safety, reduce the cost due to minimal consumption of drug and will help in early post-operative recovery. The present study discusses a fuzzy proportional-integral-derivative (fuzzy PID) based controller to suggest the change in quantity of isoflurane to be delivered to the patient, for the maintenance of the desired anaesthetic depth, as targeted by the anaesthesiologist. Depth of Hypnosis (DoH) of the patient is measured using BIS™ index and is used as the measured variable in the controller designed for the maintenance of anaesthesia during surgery. The fuzzy PID controller efficiently deals with the nonlinearity of physiological systems
Investigation of Long Period Grating as refractive index sensor
No full textIn this paper, we have theoretically and experimentally investigated the response of Long Period Grating (LPG) as refractive index sensor. The response has been checked for the refractive index ranging from 1 to 1.458. It was found that the experimental results are very close to the theoretically simulated results. The ambient refractive index response of an LPG over a much wider index range has been modeled for values both less and more than the cladding refractive index
Disaster Mitigation through instrumentation
No full textThe natural hazards such as earthquake, landslides, snow avalanches, cyclones, floods etc which may appear at any time and damage the property & life of masses in no time, have been of major concern in India since long. The group at CSIR-CSIO is engaged in the design, development and
batch production of instruments related to seismological, snow avalanche, landslide monitoring,railway safety and other geotechnical applications for the last three decades. Calibration facility for seismic instruments and sensors has also been set up in the laboratory. A network of three
Seismological observatories - at Chandigarh, Nauni (Solan) and Sunder Nagar (H.P.) are operational round the clock for monitoring Seismicity in & around Chandigarh. The technologies developed by CSIO in this area are being used by various academic, research and meteorological departments
Template Matching to Enhance HUD Colour Images
No full textHead up Display (HUD) is a means of presenting information
to the pilot key flight instrument data onto a set of glasses regarded as „beam combiner‟ positioned just in front of the pilot‟s line of sight looking ahead out of the aircraft helping him in key tasks like take off, navigation and landing. It also improves the situational awareness greatly by displaying flight, sensor and instrument data in the pilot‟s forward field of view. HUD employs a CCD camera mounted right in front of the pilot, that is, between the beam combiner and the pilot for recording the view comprising of the outside world and the HUD symbology as seen by the pilot. This recorded video is sent directly through telemetry to the flight analysis ground station for real time flight data analysis as seen by the pilot as
well as to guide the pilot. The recorded video is also used for post flight analysis as well as video source for HUD repeater display used by the pilot occupying rear cockpit seat in case of trainer aircrafts. The inconsistent and improper lighting conditions prevailing during weather conditions such as rain, snow, fog, bright sunny daylight and against the white clouds causes either insufficient or excessive light intensity at different spatial locations falling on the CCD camera sensor head resulting in degraded image quality with very low contrast. The work presented in this paper attempts to tackle this problem through theoretical study and experimental analysis. A customized template matching technique is also presented here for enhancement of the video captured by HUD camera. Added to this, hardware based methods are also suggested which can be employed for real time video enhancement
Use of Orthogonal Array to Study the Effect of Various Parameters on Liquid Metal based Microchannel Cooling
No full textWith increase in demand for efficient cooling technologies in electronic systems, use of microchannels with liquid metals as cooling medium has gained significant attention. To analyze the effect of various geometrical parameters on microchannel performance with such coolant, Taguchi Orthogonal Arrays are used in this study. To replicate the results for simulation, external noise is introduced in two parameters, channel width and depth. In addition, channel wall and base thickness along with type of material affecting the performance is also analyzed. Results show that channel width, height and substrate thickness at the base are the prime factors of concern. In addition, interactive effect of wall and base thickness is also found to affect the performance significantly and their low values for optimum performance is recommended