3D Localisation of Target using Elevation Angle Algorithm with the use of Ground Radars

A new novel method based on elevation angle algorithm (EAA) is proposed in this paper, to obtain 3D position of target using range and azimuth measurements of two ground 2D radars. The EAA estimates optimal target elevation angle wrt contributing radar by solving a non-linear optimisation problem using Levenberg-Marquardt method in geo-centric frame such as earth-centred-earth-fixed. The target position in geodetic frame (WGS84) is then obtained using slant range, azimuth and estimated elevation angle. The proposed method is evaluated using simulated but realistic radar data and accuracy of estimated position is found to be comparable with true position (error within acceptable limit). The method is also evaluated with real data from actual ground 2D radars and estimated target position is found to be comparable with reference navigation data (GPS) on-board of target. For each radar, corresponding Extended Kalman filter (EKF) is used to handle noisy, asynchronous measurements and to provide estimated range and azimuth at common reference time for altitude estimation using proposed EAA method. In case of real data, the estimated altitude is found to be comparable GPS altitude with error less than 5 % of true altitude. From the study, it is found that EAA is suitable to estimate target position using measurements from only two contributing asynchronous 2D radars in real-time as compared to some other techniques such triangulation and Trilateration where at-least three radars are required to get the position of target. This method can be useful to utilise network of vintage long range 2D radars to determine target position and to fill the gap wherever/whenever target is out of detection range of 3D radars. In addition, EAA method is compared with commonly used methodology such range only localisation and results are presented

Studies on the adsorption of arsenic on Cali[6]arene.

p-tert-butyl calix[6]arene (PTC6) was synthesized and characterized by solid- and liquid-state NMR and LC-MS techniques. The adsorption of arsenite and arsenate on calix[6]arene under different pH conditions and adsorbate doses was studied. The maximum adsorption of arsenic species on calix[6]arene was observed around neutral pH and the adsorption density of As (III) was higher than that of As (V). The adsorption of neutral H3AsO3 and negatively charged H2AsOS4 molecules on calix[6]arene was attributed to the condensation reaction between hydroxyl groups of PTC6 and arsenic species. The complexation of arsenite with phenolic oxygen was confirmed by solid-state 13C NMR CP-MAS. Exo attack mechanism was proposed to describe the interaction of arsenous and arsenic acid molecules with PTC6. The specific interaction between calix[6]arene and arsenic species was further substantiated by zeta-potential (z-potential) measurements and free energy of adsorption. The free energy of adsorption (Gads) estimated from Stern–Grahame equation was found to be 25 kJ/mole for As (III) and 19 kJ/mole for As (V)

Adsorption of Oleic Acid on Calcium Minerals

Adsorption of oleic acid on nuorite and calcite was studied by adsorption isotherms and Electro kinetic measurements. The adsorption of oleic acid on calcium minerals was observed to proceed initially by monolayer formation at lower concentrations followed by the physical adsorption of hydrocarbon chains in the second layer and finally the precipitated calcium oleate at higher concentrations. Compared to calcite. oleic acid was found to adsorb on fluorite at very low equilibrium concentrations. From the zeta potential measurements. the iso electric point (iep) values of fluorite and calcite are found to be 10.5 and 8,5 respectively. In presence of oleic acid the iep values of fluorite and calcite are shifted to 3.0 and 5.8 indicating specific chemical-interaction between surface calcium and oleate ions. The Free energy of adsorption was calculated from adsorption and Zetapotential measurements. The sign and magnitude of free energy of adsorption suggest the chemisorption of oleic acid on fluorite

A novel de-tert-butylation of p-tert-butylcalix[n]arenes

A facile de-tert-butylation method was developed for the synthesis of calix[n]arenes. A mixture of p-tert-butylcalix[n]arene, sodium dithionite and tri-fluoro acetic acid were refluxed at 80-90 ºC for 24 h. The calix[n]arenes with yields ranging from 80-92 % was achieved

Performance Enhancement of Cisc Microcontroller

Increase in the speed of the system always demands for a major alteration on the existing system, which result in overall cost of the implementation of a system. Generally, CISC controllers are used for control operations, which have large number of instruction sets and take a large amount for processing due to its multiple sizes. For very high speed of controlling these controllers may fail to operate properly. The alternate solution is the RISC controllers, which are considerably faster than the normal CISC controllers. But these controllers have got various limitations as less instruction operations, complex register operation, costlier than the CISC controller etc. The only solution to this problem is the enhancement to the operational speed of a CISC controller, by enhancing the overall controller operation. Additionally, today�s controller doesn�t support the floating-point operation for signal processing. The enhancement of existing CISC controller by pipelining the overall operational flow of a CISC microcontroller and it includes the enhancement of UART. This research work is to be implemented using VHDL language and simulated using Active-HDL tool for functional verification

Evaluation and Improvement of Distribution System Reliability Indices using ETAP Software

Reliability assessment is the most important factor in designing and planning of distribution system that should operate in an economical manner with minimal interruption of customer loads. This is due to the fact that the distribution system provides the final link between a utility transmission system and its customers. It is observed that more than 80% of all customer interruptions occur (i.e., power quality issues) due to component failures in the distribution system. That report quantifies the expected reliability indices such as interruption frequency and interruption duration during the entire year. Many research findings are out there to assess the reliability of the power system. Further, due to the wide growth of distributed generation in electrical power, investigating their impact on system reliability, it becomes an attractive area of research. In this paper, the reliability evaluation of distribution system using a minimal cut set method based on the FMEA technique is described and applied to the IEEE RBTS Bus-2 and Indian practical distribution system (33/11 kV). Development of ETAP software is presented for calculating reliability indices. Further, improvement of reliability with introducing of Distributed Generation is presented. Reliability indices are load point indices and system indices which includes, System Average Interruption Frequency Indices (SAIFI), System Average Interruption Duration Indices (SAIDI), Customer Average Interruption Frequency Indices (CAIFI), Customer Average Interruption Duration Indices (CAIDI), Energy Not Supplied (ENS), Average Energy Not Supplied (AENS), etc. These indices are shows the reliability performance of the system

Studies on the Zetapotential of Calcite/p-Sulfonatocalix[ 4,8]arenes

Zeta potential of calixarenes has been reported for the first time. The water-soluble calixarenes has been used as dispersion media in solid/liquid interface. p-sulfonato-calix[4]arene (PSC4) and p-sulfonato-calix[8]arene (PSC8) were synthesized and characterized by FTIR, NMR, mass spectrometry, and HPLC techniques. It was proved that the zeta potential is a fast and simple measurement to know the adsorption behavior of sufonato calixarnes on calcite. The chemisorption of p-sulfonato-calix[n]arene was confirmed by shift in iso electric point, adsorption studies and FTIR. The calculated free energy of adsorption value and its sign suggests the chemical interaction between the calcite surface and p-sulfonato calix[4]and[8]arene

Flocculation of iron ores using magnafloc polymers

Flocculation of iron ore fines using two different anionic polymers based on polyacrylamide.The results obtained were presented

Finfish resources around Andaman and Nicobar islands

The average catch rate of finfishes obtained by FORV Sagar Sampada from the survey area in the Andaman Sea was 259 kg/hr and the yield ranged from 8.6 to 1260 kg/hr. Silver bellies was the most abundant component (37.5%) with a catch rate of 96.9 kg/hr. Carangids, elasmobranchs and perches accounted for 20.3%, 11.9% and 8.0% of the total catch and the corresponding catch rates were 52.5, 31.1 and 20.8 kg/hr respectively. The highest catch rate of 1260 kg/hr was recorded from 13°10'N - 92°37'E at a depth of 65m. The catch rate indicated that the depth zone 51-100 m is productive and yielded 84.7% of the total catch at a catch rate of 501.4 kg/hr. Although the pelagic trawl was operated at 38 stations, the catch realised was neghgible (0.83 kg/hr)