Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
Item A simple, convenient and accurate gravimetric method for the determination of silver is presented. 4-Amino-3-methyl-5-mercapto-1,2,4-triazole precipitates silver quantitatively from ammoniacal tartrate medium. The complex is weighed as AgC3H5N4S after drying at 120-30°. Separation of silver from a large number of cations is described. Application of the method for quantitative analysis of alloys and complexes of silver is reported. The average relative error for the range 20-70 mg of silver is ± 0.25% and the relative standard deviation at the 40-mg level is 0.2%. © 1978.(4-Amino-3-methyl-5-mercapto-1,2,4-triazole as a gravimetric reagent for determination of silver in silver compounds, alloys and complexes) Gadag, R.V.; Gajendragad, M.R.1978Item In this paper E-stable methods of O(h4), O(h8) and O(h12) are derived for the direct numerical integration of initial value problems of second order differential equations with exponentially decreasing solutions. Numerical results are presented for both linear and nonlinear problems. © 1985 BIT Foundations.(Kluwer Academic Publishers, E-stable methods for exponentially decreasing solutions of second order initial value problems) Ananthakrishnaiah, U.1985Item Separately excited dc motors fed by sequentially operated multistage converters are commonly used in mainline traction. The drive performance can be greatly improved by operating the fully controlled converters with controlled flywheeling. The analysis and performance of a dc drive fed by two-stage sequentially operated fully controlled converters with controlled flywheeling are described. The modes of operation of the converter system are identified, and a method for calculating performance, taking these modes of operation into account, is presented. The nomograms and an analytical method of calculating them are presented for computing the optimum value of filter inductance. The performance of the drive with controlled flywheeling is compared with performance using normal control. The modes of operation and certain aspects of drive performance are verified experimentally.(TWO-STAGE SEQUENTIALLY OPERATED REGENERATIVE CONVERTERS WITH CONTROLLED FLYWHEELING.) Bhat, Subbanna P.; Dubey, Gopal K.1985Item WAVE FORECASTING FOR THE WEST COAST OF IHDIA(American Society of Civil Engineers (ASCE), 1970) Dattatri, J.; Renukaradhya, P.S.The applicability of the general Wave Forecasting procedures like the SMB and the PNJ methods, to the Indian coasts is studied. The study consisted in analysing the bynoptic charts to obtain the necessary wind characteristics. The computed wind characteristics were used in the above Forecasting methods to yield significant wave heights These were compared with the wave characteristics as recorded by a sub-surface pressure type recorder after suitable modifications to account for the attenuation of wave pressure with depth. The predicted wave heights compare well with the recorded wave heights and the SMB method predicts wave heights better for the case studied. © 1970 American Society of Civil Engineers.Item FIELD STUDY OP SURATHKAL BEACH(American Society of Civil Engineers (ASCE), 1970) Suryaprakasa Rao, P.; Kassim, P.Beach profile observations and sediment sampling were carried out for six months at frequent intervals to study the seasonal changes of the beach. Iht study is helpful in bringing out the qualitative and quantitative changes of the beach under varying wave and tide conditions. Useful information is obtained and presented regarding i) the maximum rate of erosion ii) the total quantity of material eroded iii) the critical wave steepness values which changed from depositing to eroding nature and iv) the sediment characteristics of the beach. © 1970 American Society of Civil Engineers.Item On the problem of predicting burning rates in a spark ignition engine(SAE International, 1975) Samaga, B.S.; Murthy, B.S.In this paper, formulation of a mathematical model for flame propagation in a spark ignited reciprocating engine has been described. As against the common practice of assuming a laminar flame propagation model with a suitable multiplying factor for turbulence effects, a more logical approach has been adopted bringing in the concept of an engine Reynolds parameter as the criterion to determine the combustion acceleration due to turbulence. The laminar burning velocity is calculated from Semenov's thermal model for the instantaneous unburned gas condition during combustion and is augmented for engine gas turbulence through an empirical function of the engine Reynolds parameter assuming wrinkled flame model. The turbulent flame velocity thus obtained is then corrected for flame transportation due to the expansion of the burning gases. The empirical constants in the formula have been evaluated in correlation to results of extensive experimentation on a single cylinder variable compression ratio research engine.Item Geomorphological Studies of the Estuary of River Netravati Near Mangalore(American Society of Civil Engineers (ASCE), 1975) John, E.J.; Cheryan, K.P.A number of factors such as wave conditions, tides, river flows, sediment charge, and ocean currents affect the features of an estuary. The understanding of the morphology of an estuary is essential on purely scientific considerations as well as applied to harbours. An attempt is made to study these inter-related and unsteady features and their combined effect on an estuary qualitatively. The estuary selected for the study is the one near Mangalore on the West Coast of India at latitude 12 51' north and longitude 74° 50' east, where two rivers, viz., river Netravati and river Gurpur meet together and join the sea. An effort is made to analyse the changes in the estuary in terms of prevailing wave conditions, river flows and sediment transport. © 1975 American Society of Civil Engineers (ASCE). All rights reserved.Item Investigation of a turbulent flame propagation model for application for combustion prediction in the S.I. engine(SAE International, 1976) Samaga, B.S.; Murthy, B.S.This paper is a follow-up of the authors' earlier paper(1)* in which the development and evaluation of a mathematical model for turbulent flame propagation in the S.I. Engine had been described. The present paper gives a report of further studies regarding the general applicability of this model for S.I. engine combustion prediction. A simplified scheme has also been suggested to predict the pollutant emission by a correlation of the computed equilibrium mole fractions to the measured emission levels of 'CO' and 'NOx' in the exhaust. A wide variety of operating conditions has been considered and the model is applied in a simulation program to compute the combustion and exhaust emission characteristics for each operating condition. The predicted results, in general, are in conformity with the experimentally measured results reported in literature. Copyright © 1976 Society of Automotive Engineers, Inc. All rights reserved.Item OCEAN WAVE RECORD ANALYSIS BY TUCKER'S METHOD - AN EVALUATION(American Society of Civil Engineers (ASCE), 1977) Dattatri, J.; Nayak, I.V.[No abstract available]Item PERFORMANCE CHARACTERISTICS OF SUBMERGED BREAKWATERS(American Society of Civil Engineers (ASCE), 1978) Dattatri, J.; Raman, H.; Jothi Shankar, N.[No abstract available]Item CONVECTIVE HEAT TRANSFER BY AXIAL FLOW IN AN ANNULUS WITH POROUS LINING.(Pineridge Press, 1983) Channabasappa, M.N.; Umapathy, K.G.; Nayak, I.V.This paper covers a theoretical model of convective heat transfer by axial flow in an annulus bounded by two long concentric circular cylinders, the outer surface of the inner cylinder being provided with a non-erodible porous lining and the two bounding surfaces being maintained at constant temperatures. The analysis makes use of the velocity slip and the temperature slip boundary conditions at the interface and employs Brinkman model to obtain the velocity field in the porous zone. The influence of various parameters on the velocity and temperature fields is studied.Item SOLAR INSOLATION AT SURATHKAL - WEST COAST OF INDIA.(Pergamon Press, 1986) Nijaguna, B.T.[No abstract available]Item ELECTRO-CHEMICAL BEHAVIOUR OF COATED REINFORCEMENT IN CEMENT CONCRETE.(1987) Patil, B.T.; Gajendragad, M.R.; Ramchandran, T.; Ranganna, G.; Sudhaker Nayak, H.V.Concrete constructions exposed to marine environments eventually suffer from corrosion of embedded steel rods, in its advanced state, this corrosion can crack the concrete and weaken the structure. The behaviour of paint coated reinforcements in cement concrete containing different amounts of chloride through an electrode polarization technique. Coated steel rods perform better as far as corrosion of rebar is concerned.Item STUDIES ON SUBSURFACE WATER POTENTIAL AND QUALITY FOR IRRIGATION.(Int Assoc of Hydrological Sciences, 1987) Ranganna, G.; Gajendragad, M.R.; Naganna, C.; Gurappa, K.M.; Nayak, I.V.; Chandrakantha, G.; Rao, P.R.M.The region of Western Ghats comprising the Sahyadri Mountain chain in southern India has remained underdeveloped notwithstanding its rich natural resources and flora and fauna. The Aladangadi Hole (river) basin is one such area. Although the basin receives very heavy rainfall, it faces water scarcity problems and thus has remained undeveloped. Intense development in the coastal region has created increasing demands for fresh water. As a pilot study, hydrological investigations for the yield, quality of water and soil, aquifer parameters, soil-water-crop compatibility, groundwater potential and Landsat imagery studies have been undertaken. This paper highlights several aspects of irrigation for an all-round development of the basin.Item Interactions of a group of vertical cylinders in water waves(Publ by American Soc of Mechanical Engineers (ASME), 1989) Reddy, K.I.S.; Kumar, B.N.; Dattatri, J.An analytical procedure involving Bessel functions is applied to investigate the wave interactions with a group of vertical circular cylinders. Considering the scattered wave at each cylinder in terms of Hankel functions, the inter-scattering of the waves from other cylinders is considered in the investigations. Wave forces and hydrodynamic coefficients in terms of the diffraction characteristics of single cylinders are evaluated for various groups of cylinders. A two cylinder group is considered for experimental verification of the theory. A comparison of the present procedure with boundary element and finite element methods is made.Item Data/voicenideo integration on fiber distributed data interface(Institute of Electrical and Electronics Engineers Inc., 1990) Rudramuni, B.; Hegde, G.D.; Muthangi, S.P.; Paulraj, A.The Fiber Distributed Data Interface (FDDI) is a 100 megabit per second (Mbps) Local Area Network that uses Optical Fiber as the medium. It provides both the high bandwidth and low latency needed to match the capacity of future personal computers. Hence it is expected to become the preferred local area network systems of the 1990s. The FDDI protocol is based on a timed token ring access method. In this paper, we propose a media access control protocol for combined Data/Voice/Video services on FDDI. The most important service requirement for the packetized Voice and Video is the transport of this data with tolerable delays. Ile effect of multiple Voice and Video channels on the asynchronous data traffic and the capacity to handle these services on FDDI is investigated by means of simulation methods. © 1990 IEEE.Item Performance of plasticized/superplasticized concrete in the marine environment(Publ by ASME, 1994) Patil, B.T.; Gajendragad, M.R.; Ranganna, G.; Wagh, A.B.; Sudhakaran, T.The use of admixtures, particularly plasticizers and superplasticizers in concrete, is gaining much attention now a days. Their use increases the workability of concrete which allows reduction in W/C ratio, resulting in reduced permeability. The major factor affecting durability of RCC in an aggressive environment like marine is the corrosion of reinforcement due to the corrosion inducing substances present in the media, which reaches its surface by ingression through concrete. Hence one can expect that the use of these admixtures can improve the performance of RCC in the marine environment provided proper W/C ratio is used. In the present study, the performance of RCC containing three indigenous admixtures namely, a plasticizer and two superplasticizers at different dosages with reduced W/C ratio was studied. The study was carried out by assessing the corrosion of reinforcement in concrete electrodes containing these admixtures by means of potentiostatic polarization technique. The results show that the corrosion resistance of reinforcement in increased by the use of admixtures.Item Minimizing power consumption in multiple fan networks by optimum fan selection(Soc for Mining, Metallurgy & Exploration Inc, 1995) Kumar, G.Vijaya; Sastry, V.R.; Krishna Rao, G.V.One of the main objectives while planning ventilation systems for mines with multiple fans is minimization of the total airpower consumption of the mine. Solution of this problem by conventional ventilation network analysis programs is tedious and time consuming, and may not yield optimum results in all the cases. The paper presents an algorithm for solving multiple fan networks by finding optimum combination of fan operating points for required airflow distribution in the ventilation system.