5. Miscellaneous Publications
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Item Asbestos mining - campaign against its utilisation in western world(1989) Venkat Reddy D.[No abstract available]Item Chemical amplification method for the determination of atmospheric sulphur dioxide(1997) Pandurangappa M.; Balasubramanian N.A sensitive spectrophotometric method is described for the determination of trace levels of sulphur dioxide in ambient air after fixing the gas in triethanolamine (TEA) or triethanolaminemannitol absorbing solutions. The method is based on the reaction of sulphur dioxide with iodine to form iodide and after the extraction of unreacted iodine, the iodide was oxidized to iodate by bromine. The generated iodate is utilized to oxidize hydroxylamine to nitrite which produces an azo dye in the presence of p-nitroaniline and N-(l-naphthyl)ethylenediamine dihydrochloride (NEDA) in acid medium with maximum absorption at 545 nm. The system obeys Beer's law over the concentration range 0-5 μg of sulphur dioxide in a final volume of 25 ml. The relative standard deviation is 2.5% at 4 μg of sulphur dioxide (n = 10). The interference of other gaseous species were suitably overcome by the proper reaction conditions. The developed method was applied to determine low levels of sulphur dioxide generated using permeation devices and ambient levels of sulphur dioxide in the vicinity of a sulphuric acid plant.Item Transmission and storage of medical images with patient information(2003) Acharya U. R.; Subbanna Bhat S.; Kumar S.; Min L.C.Digital watermarking is a technique of hiding specific identification data for copyright authentication. This technique is adapted here for interleaving patient information with medical images, to reduce storage and transmission overheads. The text data is encrypted before interleaving with images to ensure greater security. The graphical signals are interleaved with the image. Two types of error control-coding techniques are proposed to enhance reliability of transmission and storage of medical images interleaved with patient information. Transmission and storage scenarios are simulated with and without error control coding and a qualitative as well as quantitative interpretation of the reliability enhancement resulting from the use of various commonly used error control codes such as repetitive, and (7,4) Hamming code is provided. © 2003 Elsevier Science Ltd. All rights reserved.Item Casting/mould interfacial heat transfer during solidification in graphite, steel and graphite lined steel moulds(2003) Prabhu K.N.; Mounesh H.; Suresh K.M.; Ashish A.A.Heat flow between the casting and the mould during solidification of three commercially pure metals, in graphite, steel and graphite lined steel moulds, was assessed using an inverse modelling technique. The analysis yielded the interfacial heat flux (q), heat transfer coefficient (h) and the surface temperatures of the casting and the mould during solidification of the casting. The peak heat flux was incorporated as a dimensionless number and modeled as a function of the thermal diffusivities of the casting and the mould materials. Heat flux transients were normalised with respect to the peak heat flux and modeled as a function of time. The heat flux model proposed was used to estimate the heat flux transients during solidification in graphite lined copper composite moulds.Item Noise analysis of heavy earth moving machinery deployed in opencast mines and development of suitable maintenance guidelines for its attenuation - Part 2(2004) Vardhan, H.; Rao Y.V.; Karmakar, N.C.The noise analysis of heavy earth moving machinery deployed in opencast mines and development of suitable maintenance guidelines for its attenuation were discussed. The impact of periodic maintenance on the noise characteristics of machines was studied. The maintenance schedule for which maximum fluctuation in the noise level occured was analyzed. The noise control of heavy earth moving equipment used in opencast was also elaborated.Item Millennium development goals and biodiversity(2005) Madhyastha M.N.; Rekha P.D.[No abstract available]Item Noise problem and its control for heavy earth moving machinery deployed in opencast mines - A critical review(2006) Vardhan, H.; Rao Y.V.; Karmakar, N.C.Worldwide, increasingly stringent regulations are coming into force, limiting the exposure of workers to industrial noise. Industrial noise and its consequences, is thus growing importance to employers, local and central government officials, trade unions, occupational hygienists and physicians and insurers. India is not an exception far this. The mining industry in India is facing serious problem of noise due to increasing demand of minerals for which large capacity machines are being deployed producing high noise levels. The present paper thoroughly reviews the noise problem and its control for heavy earth moving machinery's deployed in opencast mines both in India and worldwide. The various noise control approaches for heavy earth moving machinery's deployed in opencast mines are also discussed.Item Assessment of heavy earth-moving machinery noise vis-à-vis routine maintenance(2006) Vardhan, H.; Karmakar, N.C.; Rao Y.V.Exposure to noise from various types of equipment/machinery has been identified as a critical health hazard for personnel working in the Indian mining industry. Heavy Earth Moving Machinery (HEMM) used in mines has been identified as a major source of noise, and several earlier investigators have proposed various types of retrofit measures on these machines to reduce noise. The present work was taken up with the objective of evaluating the noise generation characteristics of HEMM as influenced by periodic maintenance. Detailed noise measurements were carried out in a large open pit coal mine located in India. The effect of maintenance on noise production was assessed for ten dumpers and three dozers by measuring the A-weighted one-third-octave band sound pressure levels after the machines had been subjected to maintenance at the end of 300 hours, 500 hours, 750 hours and 1000 hours of use. Measurements were also carried out to assess the effect of maintaining specific HEMM systems noise characteristics at 1000 hours. Assessment of sound pressure levels at each periodic maintenance revealed major sound level reductions with 1000 hours maintenance. The data also identified the major noise generating systems in HEMM as air systems, exhaust systems, cooling systems and fuel systems. © 2006 Institute of Noise Control Engineering.Item Welcome message(2006) Patniak L.M.; Trivedi K.S.; Sivakumar G.; Ray I.; Misra S.; Venugopal K.R.; Sekaran K.C.[No abstract available]Item Welcome message(2006) Patnaik L.M.; Trivedi K.S.; Misra S.; Venugopal K.R.; Sekaran K.C.[No abstract available]Item Preserving the heritage of Mattu gulla - A variety of brinjal unique to Udupi District [10](2007) Bhat R.V.; Madhyastha M.N.[No abstract available]Item Review of non-reactive and reactive wetting of liquids on surfaces(2007) Kumar G.; Prabhu K.N.Wettability is a tendency for a liquid to spread on a solid substrate and is generally measured in terms of the angle (contact angle) between the tangent drawn at the triple point between the three phases (solid, liquid and vapour) and the substrate surface. A liquid spreading on a substrate with no reaction/absorption of the liquid by substrate material is known as non-reactive or inert wetting whereas the wetting process influenced by reaction between the spreading liquid and substrate material is known as reactive wetting. Young's equation gives the equilibrium contact angle in terms of interfacial tensions existing at the three-phase interface. The derivation of Young's equation is made under the assumptions of spreading of non-reactive liquid on an ideal (physically and chemically inert, smooth, homogeneous and rigid) solid, a condition that is rarely met in practical situations. Nevertheless Young's equation is the most fundamental starting point for understanding of the complex field of wetting. Reliable and reproducible measurements of contact angle from the experiments are important in order to analyze the wetting behaviour. Various methods have been developed over the years to evaluate wettability of a solid by a liquid. Among these, sessile drop and wetting balance techniques are versatile, popular and provide reliable data. Wetting is affected by large number of factors including liquid properties, substrate properties and system conditions. The effect of these factors on wettability is discussed. Thermodynamic treatment of wetting in inert systems is simple and based on free energy minimization where as that in reactive systems is quite complex. Surface energetics has to be considered while determining the driving force for spreading. Similar is the case of spreading kinetics. Inert systems follow definite flow pattern and in most cases a single function is sufficient to describe the whole kinetics. Theoretical models successfully describe the spreading in inert systems. However, it is difficult to determine the exact mechanism that controls the kinetics since reactive wetting is affected by a number of factors like interfacial reactions, diffusion of constituents, dissolution of the substrate, etc. The quantification of the effect of these interrelated factors on wettability would be useful to build a predictive model of wetting kinetics for reactive systems. © 2007 Elsevier B.V. All rights reserved.Item Performance characteristics of horizontal interlaced multilayer moored floating pipe breakwater(2007) Hegde A.V.; Kamath K.; Magadum A.S.The paper presents the results of model scale experiments for the study of wave attenuation by horizontal interlaced, multilayer, moored floating pipe breakwater. A review of some significant floating breakwater models proposed by earlier investigators is included. For a floating breakwater the transmission coefficient (Kt) is influenced by relative width of the breakwater (W/L). Nondimensional graphs indicating the variation of Kt with respect to W/L (with Hi/L as a parameter for different Hi/d values) and Kt versus Hi/L (for a range of d/L values from 0.09 to 0.24) have been plotted. Further variation of Kt with relative depth d/L for different W/L values is also studied. From the experimental study and results obtained, it is found that the transmission coefficient decreases with an increase in relative breakwater width W/L and wave steepness Hi/L for all Hi/d values. In the present study it was observed that performance was better for breakwater configurations of W/L≥0.7 when compared with configurations of W/L<0.7. Further, the experimental results obtained were compared with the output of a mathematical model. From the comparison for Hi/L=0.04, values of Kt obtained from the present experiments were in agreement with those obtained from the mathematical model. © 2007 ASCE.Item Erratum: Special solutions of a general class of iterative functional equations (Aequationes Mathematicae (2006) 72 (269-287) DOI: 10.1007/s00010-006-2839-5)(2008) Murugan, V.; Subrahmanyam P.V.[No abstract available]Item Production optimisation using simulation models in mines: A critical review(2009) Raj M.G.; Vardhan, H.; Rao Y.V.The mining industry is faced with the task of responding to increased demand for mineral resource products, decreasing ore grades, stringent quality requirements and strict environmental regulations in trying to meet the demands of the economy. This situation has necessitated the search for more scientific and technological innovations that enable profitable mining like simulation studies. In this paper, system simulation studies in underground and open-pit mines, shovel truck simulation have been discussed in detail. The study shows wide applicability of simulation studies in various operations in both underground and open-pit mines. Copyright © 2009, Inderscience Publishers.Item Technical aspects of biodiesel and its oxidation stability(2009) Kapilan N.; Ashok Babu T.P.; Reddy R.P.Biodiesel is a clean burning alternative renewable fuel made from natural renewable sources. It is defined as mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, which conform to ASTM specifications for use in diesel engines. Biodiesel present a very promising alternative fuel to diesel oil and properties of this oil offer the advantage of immediate substitution in existing diesel engines with little or no modifications at all. But one of the major technical problems associated with the biodiesel is its susceptibility to oxidation, which can cause the fuel to become acidic and to form insoluble gums and sediments that can plug fuel filters. This is due to the unsaturated fatty acid chains and the presence of the double bond in the molecule, which produce a high level of reactivity with the oxygen, especially when it placed in contact with air. The oxidation of fatty acid chains is a complex process that proceeds by a variety of mechanisms. The various other factors influence the oxidation process of biodiesel includes light, temperature, extraneous materials, peroxides, size of the surface area between biodiesel and air. One of the methods of improving biodiesel oxidative stability includes the deliberate addition of antioxidants or modification of the fatty ester profile. This article discusses the technical aspects of biodiesel and its oxidation stability.Item International Journal of Ecology and Development: Editorial(2009) Hegde A.V.[No abstract available]Item Heat transfer during quenching and assessment of quench severity-A review(2009) Narayan Prabhu K.; Fernandes P.In the heat treatment of steel, quenching is done to prevent ferrite or pearlite formation and allows formation of bainite and martensite. For a particular grade of steel, the effectiveness of quenching depends on the cooling characteristics of the quenching medium. The cooling rate is not a constant throughout the quenching process; instead it varies depending upon the various stages that occur during the quenching process. Knowledge of heat transfer during various stages of quenching and kinetics of wetting of the quench medium is fundamental to the understanding of the relationship between material, quench medium, microstructure, and properties. In this paper the characteristics of various quench media, the effect of process parameters on quenching, mechanisms of thermal transport, methods of assessing severity of quenching, and techniques of estimation of heat transfer coefficients are reviewed. An attempt is also made to highlight the importance of wetting kinetics of liquid media on quenching. Copyright © 2009 by ASTM International.Item Damping behaviour of cast and sintered aluminium(2009) Umashankar K.S.; Abhinav A.; Gangadharan, K.V.; Vijay D.Estimating damping in structures made of different materials and processes still remains as one of the biggest challenges. Aluminium is one such pioneer material which is being used extensively in aerospace, automotive and the manufacturing industry. Aluminium components are mainly manufactured by traditional casting and powder metallurgy process. The main objective of this paper is to estimate the damping ratio of aluminium manufactured through powder metallurgy (P/M) process and compare it with the commercially available Cast aluminium. Aluminium powder is compacted, sintered and then it is extruded to the required geometry. Cantilever beams of required size and shape are prepared for experimental purpose and the damping ratio is investigated. Damping ratio is determined by sweep sine test using half power bandwidth method. Free vibration tests also confirmed the damping ratios obtained by sweep sine method. It is observed that damping ratio is higher for sintered aluminium than cast aluminium which may be attributed to increased porosity. © 2006-2009 Asian Research Publishing Network (ARPN). All rights reserved.Item