024624   Gupta R K;Karthikeyan M K;Ghosh B R;Sinha P P (Mechanical Engineering Entity, Vikram Sarabhai Space Centre, , Trivandrum-609 002, Email: rohitkumar_gupta@vssc.gov.in) : Variation in microstructure and ultrasonic response in processing of Ti alloy: a review. Metals Mater Process 2006, 18(3-4), 341-50.

Titanium alloy (Ti-6AI-4V) is extensively used in aerospace systems due to its high specific strength. Processing of the alloy above the β transus temperature and below β transus temperature has distinctive advantages and limitations regarding microstructure, mechanical properties and ultrasonic quality. Reviews the microstructural changes operative during hot deformation of this alloy w.r.t. β transus temperature. A brief description of ultrasonic response observed against microstructural variation is also given. Localized variation in microstructure is correlated with ultrasonic indications.

12 illus, 21 ref

024623   Ghose A K (Indian School of Mines, , Dhanbad) : Future of underground coal mining - bord and pillar vis-a-vis longwall. J Mines Metals Fuels 2006, 54(8-9), 177-8.

2 tables

024622   George B;Siva Prasad N (NO, Gas Turbine Research Establishment, Bangalore-560 093) : Finite element analysis of squirrel cage ball bearings for gas turbine engines. Def Sci J 2007, 57(2), 165-71.

Squirrel cage ball bearings are used in recent aero engines to overcome the vibration and stability problems associated with rotor systems supported by conventional bearings. The critical design feature of squirrel cage bearing is to provide flexible support to rotor system. The outer ring of the bearing is configured such that it acts as a flexible bearing support, and hence, weight is minimised. The bearing is mounted directly on a rigid intermediate casing of a gas turbine engine. Finite element analysis helps to obtain a suitable geometry at the design stage. A 3-D model of the bearing is created using IDEAS software. Finite element analysis using contact element has been carried out for finding the deformation and stresses in the webs at various locations using ANSYS software. The deformations are compared with those of experimental values for an axial load. The deformation in the webs is used to check the pressure balance in the compressor and the load acting on the bearing. Finally, a procedure for doing the finite element analysis of ball bearings for combined axial and radial load is laid down.

8 illus, 8 ref

024621   Gautam C K (NO, Research and Developemnt Establishment (Engrs), Pune-411 015) : Analytical and experimental evaluation of a buried shelter. Def Sci J 2007, 57(2), 299-307.

Design, analysis, and testing of a buried circular cylindrical shelter has been described. The shelter may be used for personnel protection in emergency situations like accidental blast, terrorist attack, etc. Various criteria have been used for designing and analysing the shelter. The shelter has been analysed using a software package called ANSYS for finding out the stresses, deflections, buckling load factors, and buckled mode shapes. The shelter was buried under earthcover (1.5 m) and tested for the required loading.

8 illus, 2 tables, 7 ref

024620   Garai S;Upadhyay A K;Sircar J K (NO, National Metallurgical Laboratory (CSIR), Jamshedpur-831 007, Email: subha@nmlindia.org) : Potassium ion-selective membrane electrode based on heterogeneous precipitate and PVC matrix. J Metall Mater Sci 2006, 48(2), 103-08.

Membrane consisting of PVC impregnated with a heterogeneous precipitate of potassium cobalticarbonate is prepared to selectively detect K⁺ ion in aqueous system. The electrode exhibited near Nernstian response for K⁺ ion over a wide concentration range of I x 10^-5M to I x 10^-1 M with a limit of detection 10^-5 M. It has fast response time of approximately 2-3 sec and can be used for 3-4 months without observing any major deterioration. It is free from interference from ions like Na⁺ and Li⁺.

2 tables, ref

024619   Ganesan M;Padmasree S;Nagendra Rao G (Laboratory for Electro-optic Systems (LEOS), ISRO, Bangalore-560 058) : Autonomous star tracker for agile spacecraft. J Spacecraft Technol 2007, 17(1), 20-5.

Proposes an algorithm to solve the problem of star tracking for agile spacecraft. A computationally effective algorithm is developed to estimate angular rate of spacecraft using star-tracker measurements that are helpful star tracking. This algorithm uses the a fixed-gain Kalman Filter and is tested with maximum angular rates of up to 1 degree/second in IRS-P5 onboard operations. The rate estimation and tracking performance of the tracker are satisfactory. Star-tracker derived body rates are also comparable with gyro-derived rates. The algorithm is tested with maximum angular rates of up to 2.5 degrees/s. with presently available star trackers To cater to the requirement of agile spacecraft such as Cartosat-2.

5 illus, 1 table, 3 ref

024618   Dutta Majumdar J;Manna I (Metalurgical and Materials Engineering Dep, Indian Institute of Technology, Kharagpur-721 302) : Laser assisted surfae modification of Titanium and its alloys. Metals Mater Process 2006, 18(3-4), 361-86.

Over the past several decades, the commercial production of titanium and its alloys has increased steadily due to their increasing demand in aeronautical, marine and chemical industries arising out of advantageous combination of low density, high strength, excellent corrosion, thermal conductivity and bio-compatibility. However, application of titanium alloys in conditions of severe wear and friction is highly restricted due to their poor surface mechanical tribological properties. Furthermore, poor high temperature oxidation resistance further restricts the application of titanium/titanium-alloys at high temperature. Wear and high temperature oxidation are mainly surface dependent degradation and could be significantly reduced if not completely prevented by suitable modification of the microstructure and/or composition of the near surface region without affecting the bulk/interior. In this regard, a high power laser beam may be used as a source of heat to melt, alloy or clad the near surface region of a titanium-substrate and improve the surface dependent engineering properties of interest. Laser assisted surface engineering is unique because of faster processing speed and flexibility, precision and automation worthiness, environmental cleanliness, environmental cleanliness, negligible heat affected zone and possibility of retention of metastable microstructure and composition. In the past, several studies have been performed on laser assisted surface modification of titanium and its alloys for improving wear, corrosion and oxidation resistance. In this contribution, a brief overview of the utility, objective, current status and future scope of laser surface engineering of titanium and its alloys will be presented with suitable reference to and illustration of the relevant studies reported in the literature.

15 illus, 4 tables, 81 ref

024617   Dhawangale R M;Kawale S M;Waghmare M;Pandya G H;Kondawar V K (Instrumentation Div, NEERI, , Nehru Marg, Nagpur-440 020) : Electro-mechanical and infrastructure instrumentation facilities in environmental laboratory. J envir Sci Engng 2006, 48(1), 51-6.

Environmental laboratories carry out measurement and analysis of a number of physical, chemical and biological parameters. Each parameter requires some sort of instrument for its determination. Providing efficient instrumentation services to various departments of the Institute is an stupendous task. Instrumentation services in the form of installation, operation, repair and maintenanace of electro-mechanical equipment requires an in-depth experience and knowledge of the working, fabrication, design and repair of similar type of instruments so that the need of space, installation pre-requisites, budget constraints, availability of essential spares parts could be assessed. Discusses the operation of an environmental instrument repairs and maintenance, and audio-visual facilities. Suggestions for drafting of the proper specifications for procurement of laboratory equipments, such as ovens, furnaces, refrigerators, blowers, audio visual aids, and spares and accessories are given in this paper. The paper also gives the detailed information on various aspects that are needed for checking and testing of the equipment against specification before putting it in operational use. Development of a preventive maintenance program involving QC checks and keeping an inventory of essential spares required are also discussed. It is felt that such services are essential in providing smooth support to carry out research and development activities of the Institute.

2 tables, 4 ref

024616   Das S K;Godiwalla K M;Mehrotra S P;Sastry K K M;Dey P K (National Metallurgical Laboratory, , Jamshedpur-831 007, Email: skd@nmlindia.org) : Analytical model for erosion behaviour of impacted fly-ash particles on coal-fired boiler components. Sadhana 2006, 31(pt5), 583-95.

Fly ash particles entrained in the flue gas from boiler furnaces in coal-fired power stations can cause serious erosive wear on steel surfaces along the flow path. Such erosion can significantly reduce the operational life of the boiler components. A mathematical model embodying the mechanisms of erosion on behaviour, has been developed to predict erosion rates of coal-fired boiler components at different temperatures. Various grades of steels used in fabrication of boiler components and published data pertaining to boiler fly ash have been used for the modelling. The model incorporates high temperature tensile properties of the target metal surface at room and elevated temperatures and has been implemented in an user-interactive in-house computer code (EROSIM-1), to predict the erosion rates of various grades of steel. Predictions have been found to be in good agreement with the published data. The model is calibrated with plant and experimental data generated from a high temperature air-jet erosion-testing facility. It is hoped that the calibrated model will be useful for erosion analysis of boiler components.

10 illus, 2 tables, 20 ref

024615   Danabalan T L;Sahu S N (Systems Integration Group (SIG), ISRO Satellite Centre, Bangalore-560 017) : Development of gravity compensation system for satellite reflector by helium baloon. J Spacecraft Technol 2007, 17(1), 14-19.

Gravity compensation system using a helium balloon is developed for satellite reflectors. The system is based on the Archimedes buoyancy principle. Helium balloon and subsystems viz. load scale, balloon-handling system, ballast etc. are developed for the system. A suitable technique is devised to control bulges in the balloon. The full-scale gravity compensation system with helium balloon is developed and studied for helium leak rate, lift variation during scanning and net lift. The system meets requirements of zero-g simulation to the satellite reflector. Air drag, large size and helium leak rate of the balloon are the limitations of this system. Brings out design considerations, system description and test results of the gravity-compensation system by helium balloon.

4 illus, 2 tables, 3 ref

024614   Chandrasekharam K;Srinivasa Rao G;Shiva Prasad A P;Vedavathy T S (NO, ISRO Satellite Centre, Bangalore-560 017) : Simulation and implementation of a tunable C-band dielectric resonator oscillator. J Spacecraft Technol 2007, 17(1), 1-13.

Simulation, design and realization of a tunable DRO with a center frequency of 6250 MHz is presented. Simulation has been carried out on HP-Ees of CAD software. Mechanical and electronic tuning features are provided. The DRO operates over a frequency range of 6235 MHz to 6375 MHz. The output power is +5.33 dBm at centre frequency. The performance of the DRO is as per design with respect to phase noise, harmonic levels and tunability. and hence, can conveniently be used for the intended applications.

12 illus, 6 tables, 12 ref

024613   Chandrasekaran V;Murali Sankar M (Res Lab, Chemistry Dep, Mahendra Arts and Science College, Kalaippatti, Namakkal-637 501, Email: chandru_20042000@yahoo.co.in) : Adhatoda vasika alkaloids as inhibitor for aluminium corrosion in acids. J Metall Mater Sci 2006, 48(2), 93-102.

The inhibition effect of Adhatoda Vasika Alkaloids (AVA) on corrosion of aluminium in hydrochloric acid, sulphuric acid and phosphoric acid solutions has been studied. The mass loss technique was employed at 302K-333K. The inhibition efficiency increased with increase in concentration of inhibitor and decreased with rise in temperature from 302K to 333K. The absorption of this compound on the aluminium surface from the acids has been found to obey Temkin's adsorption isotherm. The values of activation energy (Ea) and free energy of adsorption (ΔGads) were also calculated.

6 illus, 2 tables, 34 ref

024612   Brncic M;Tripalo B;Jezek D;Semenski D;Drvar N;Ukrainczyk M (Faculty of Food Technology and Biotechnology, Zareb Univ, Pierottijeva 6, 10000 Zagreb, Croatia) : Effect of twin-screw extrusion parameters on mechanical hardness of direct-expanded extrudates. Sadhana 2006, 31(pt5), 527-36.

Mechanical properties of cereal (starch-based) extrudates are perceived by the final consumer as criteria of quality. Authorsinvestigate one of the important characteristics of extrudates, mechanical hardness, which is one of the main texture parameters. Texture quality has an influence on taste sensory evaluation, and thus on the acceptability of the product. Characteristics that have great influence on acceptability are crispness, elasticity, hardness and softness. These attributes are narrowly related to, and affected by, the process parameters. A 2-level-4-factor factorial experimental design was used to investigate the influence of temperature of expansion, screw speed, feed moisture content and feed rate, and their interactions, on the mechanical hardness of extrudates. Feed moisture content, screw speed and temperature are found to influence, while feed rate does not have significant effect on extrudate hardness. Mechanical properties of specimens were measured by means of compression testing, based on the concept of nominal stress, using a universal testing machine and special grips that were constructed for this purpose.

6 illus, 3 tables, 20 ref

024611   Appa Rao G;Injaganeri S S;Suresh P (Civil Engineering Dep, Indian Institute of Technology, Madras, Chennai-600 036) : Investigation of size effect on shear strength of rinforced concrete beams. J Struct Engng 2007, 33(6), 499-504.

An important parameter that is being not accounted for in the design of concrete structures is the size of structure on strength. Size effect in shear has been a serious concern owing to sudden failure of large size members at lower stress levels compared to small size members. Currently, the design provisions for shear in reinforced concrete (RC) members by various codes of practice have not accounted for the size effect. In this paper some experimental investigations have been carried out in order to study the size effect on RC beams with a shear span-to-depth ratio 1.05. Geometrically similar beams were tested by varying depth of member and compressive strength of concrete under four-point loading. The shear reinforcement was varied maintaining balanced flexural reinforcement in all the beams. Sudden failures of beams have been observed in larger size beams cast from high strength concrete (HSC), which exhibited a strong size effect on strength. The observations from the study reveal that the effect of size of beam on shear strength in the design of large size RC members should be incorporated.

7 illus, 4 tables, 20 ref

024610   Akkaya A V (Mechanical Engineering Dep, Yildiz Technical Univ, 34349, Besiktas, Istanbul, Turkey, Email: aakkaya@yildiz.edu.tr) : Effect of bulk modulus on performanc of a hydrostatic transmission control system. Sadhana 2006, 31(pt5), 543-56.

Examines the performance of PID (proportional integral derivative) and fuzzy controllers on the angular velocity of a hydrostatic transmission system by means of Matlab-Simulink. A very novel aspect is that it includes the analysis of the effect of bulk modulus on system control. Simulation results demonstrates that bulk modulus should be considered as a variable parameter to obtain a more realistic model. Additionally, a PID controller is insufficient in presence of variable bulk modulus, whereas a fuzzy controller provides robust angular velocity control.

9 illus, 1 table, 24 ref

024609   Akay A E (Forest Engineering Dep, Kahramanmaras Sutcu Imam Univ, Faculty of Forestry, 46100 Kahramanmaras, Turkey, Email: akay@ksu.edu.tr) : Minimizing total costs of forest roads with computer-aided design model. Sadhana 2006, 31(pt5), 621-33.

Advances in personal computers (PCs) have increased interest in computer-based road-design systems to provide rapid evaluation of alternative alignments. Optimization techniques can provide road managers with a powerful tool that searches for large numbers of alternative alignments in short spans of time. A forest road optimization model, integrated with two optimization techniques, was developed to help a forest road engineer in evaluating alternative alignments in a faster and more systematic manner. The model aims at designing a path with minimum total road costs, while conforming to design specifications, environmental requirements, and driver safety. To monitor the sediment production of the alternative alignments, the average sediment delivered to a stream from a road section was estimated by using a road erosion/delivery model. The results indicate that this model has the potential to initiate, a new procedure that will improve the forest road-design process by employing the advanced hardware and software capabilities of PCs and modern optimization techniques.

3 illus, 27 ref

024608   Abudhahir A;Baskar S (Electronics and Instrumentation Engineering Dep, National Engineering College, Kovilpatti-628 503) : Linearization of thermocouple characteristics using a log-ratio amplifier. J Instrum Soc India 2006, 36(4), 235-45.

New analog hardware scheme for linearization of thermocouple characteristics using a log-ratio amplifier has been proposed. The method exploits the ratiometric property of logarithmic amplifier and utilizes the inherent linearization quality of logarithmic operation to linearize thermocouple signals. Experimental and simulation studies have been carried out for some commercial thermocouples to assess the performance of the proposed method. Numerical computations were also made to evaluate the ideal performance of the method. Performance measures such at full-scale error and root mean squared error computed reveal that the proposed method performs better than the existing software linearizers for thermocouples.

4 illus, 3 tables, 18 ref

024607   Abu-Farsakh G A;Abu-Alrub R K (Civil Engineering Dep, Science & Technology Jordan Univ, P.O. Box 3030, Irbid, Jordan) : Moment and deflection redistributions in composite plates subjected to transverse loading. J Struct Engng 2007, 33(6), 487-98.

New finite element scheme is developed, which incorporates a comprehensive constitutive material model for fiber-reinforced laminated composite (FRC) plates subjected to transverse loading. This material model is based on expressing the nonlinear secant mechanical properties as a function of the plastic strain energy density of an equivalent linear-elastic system. The model is combined with a relevant failure criterion to formulate a complete plane-stress constitutive relationship for FRC laminates up to the ultimate stress condition. The effect of material nonlinearity on the redistribution of lateral deflections and moment-resultants of FRC laminated plates is investigated. Besides, the effect of fiber-orientation and plate geometry for both linear and nonlinear analysis is also determined. In order to validate the methodology used in the study, results of several numerical examples for various laminate configurations and material properties are compared with the corresponding available experimental data.

21 illus, 1 table, 27 ref

024606   Abdalla K M (Civil Engineering Dep, Science & Technology Dep, , 22110 Irbid, Jordan) : K-nut factor of high strength bolts - part II. J Struct Engng 2007, 33(6), 459-63.

Thread lubricant condition of high strength bolts is important in determining the bolt-tensile characteristics. Presents result of tests performed upon 20 mm (3/4-in.) diameter, 76.2 and 152.4 mm (3 and 6 in.) long, A325 (M164) and A490 (M243) bolts, as the length and location of treatments surface are varied. Testes were performed upon one hundred forty four bolts; sixty four A325 of three inches in length, forty eight A325 of six inches in length, twenty A490 of three inches in length, and twelve A490 of six inches in length. One hundred forty four nuts and washers were tested, one eighty eight nuts type 2H, and fifty six nuts type C to determine the effect of the variables (nut type, bolt length, bolt type and Control Fluid) on K-nut factor of the bolt-nut-washer assemblage. Factors that affect the pretension-torque relation are K-nut factor, bolt diameter, bolt-material strength, thread conditions, and the surface conditions at the nut-washer-joint interface. Control Fluid was found to decrease the coefficient of friction on coated parts and to control the tension obtained with a given torque upon assembly.

5 illus, 9 tables, 10 ref

023741   Wu A;Xu J;Zhou J;Shen H (NO, Shanghai Institute of Ceramics, Chinese Academy of Science, No. 1295 Dingxi Road, Shanghai-200 050, Email: crystalxu@mail.sic.ac.cn) : Piezoelectric property of Sr₃Ga₂Ge₄O₁₄ single crystals. Bull Mater Sci 2007, 30(2), 101-4.

New piezoelectric single crystal, Sr₃Ga₂Ge₄O₁₄ (SGG), has been grown successfully by the vertical Bridgman method with crucible-sealing technique. SGG crystal up to 2" in diameter has been obtained. The relative dielectric constants, the piezoelectric strain constants, elastic compliance constants and electromechanical coupling factors have been determined with resonance and anti-resonance frequencies method by using the impedance analyzer (Agilent 4294A). The results show that the piezoelectric strain constants and electromechanical coupling factors of SGG single crystal are higher than those of LGS single crystals making it a potential substrate material for surface-acoustic wave applications.

4 tables, 1 illus, 7 ref

023740   Wang J;Shi J;Wang J;Ling Y;Bo X (NO, Hefei Institute of Electronic Engineering, Hefei-230 037, People's Republic of China) : Infrared extinction coefficients of artificial aerosol. Def Sci J 2007, 57(4), 563-70.

The double-band infrared extinction coefficients of the artificial aerosol have been calculated and compared with the experimental data. The particulates were assumed to be small spheres and Mie's theory was employed with the grain size distribution function being lognormal. The numerical and the experimental results show that the size distribution and the materials of the particles are decisive of their infrared extinction capability.

4 tables, 12 illus, 5 ref

023739   Sushil Kumar;Gomekar S P;Maini A K (Laser Science & Technology Centre, , Delhi-110 054) : High-angular resolution laser threat warner. Def Sci J 2007, 57(4), 507-11.

Design and development aspects of a high-angular resolution laser-threat warner developed at the Laser Science & Technology Centre (LASTEC), Delhi are presented. It describes a high-angular resolution laser-threat warner capable of giving warning with a resolution of ± 3° when it is exposed to laser radiation from visible and near-IR pulsed solid-state laser source. It has a field of view of 90° in the azimuth direction, whereas the elevation coverage is between-5° and + 25°. It is capable of handling multiple types of laser threats covering wavelength from 400 nm to 1100 nm and has an operational range of 4 km for a Q-switched laser source energy (10 ns) of 10 mJ/pulse and output beam divergence of 1 mrad. Also describes its simulated evaluation process and field-testing which it has undergone. The result of field-testing confirms that it meets all its performance specifications mentioned above.

1 table, 3 illus, 8 ref

023738   Suri P;Sona Rani (Computer Science and Applications Dep, Kurukshetra Univ, Kurukshetra, Email: sona_malhotra@yahoo.com) : Use of fixed device address during connection establishment. J Analysis Computn 2006, 2(1), 119-24.

Bluetooth is being envisioned simply as a wire replacement technology. Its most commonly described application is that of a "cordless computer" consisting of several devices including a personal computer, possibly a laptop, keyboard, mouse, joystick, printer, scanner, etc., each equipped with a Bluetooth card. There are no cable connections between these devices, and Bluetooth is to enable seamless communication between all them, essentially replacing what is today achieved through a combination of serial and parallel cables, and infrared links. However, Bluetooth has the potential for being much more than a wire replacement technology, and the Bluetooth standard was indeed drafted with such a more ambitious goal in mind. Bluetooth holds the promise of becoming the technology of choice for adhoc-networks of the future. This paper introduces a number of problems faced by the Bluetooth technology when attempting to use it for building adhoc networks. The paper provides a brief overview of Bluetooth and describes some of the major issues that need to be addressed, if it is to be successful as a networking technology.

12 ref

023737   Suri P;Sona Rani (Computer Science and Applications Dep, Kurukshetra Univ, Kurukshetra, Email: sona_malhotra@yahoo.com) : Improved security mechanism using bonding technique. J Analysis Computn 2006, 2(1), 111-17.

Bluetooth technology provides conveniences ranging from simply substituting for wires of electrical household products to constructing home network systems. Bluetooth technology-based services in public raises security issues in providing a secure Bluetooth link for unknown Bluetooth peers. In this paper, Authors present a method of Bluetooth pairing in which authentication is divided into two parts. In contrast to current method that requires PIN to be entered manually into the Bluetooth devices, this method will be more secure and reluctant to man in the middle attack.

3 illus, 6 ref

023736   Sridevi D (Electronics Dep, L.A.D. and Smt. R.P. College for Women, Nagpur) : Nanomaterials and photovoltaics. Res J 2007, 3(1), 1-8.

The role of nanomaterials and quantum dots of new semiconductor materials and novel configurations of solar photovoltaics are discussed.

4 illus, 26 ref

023735   Sindhu T K;*Sarathi R;Chakravarthy S R (Electrical Engineering Dep, IIT Madras, Chennai-600 036, Email: rsarathi@iitm.ac.in) : Generation and characterization of nano aluminium powder obtained through wire explosion process. Bull Mater Sci 2007, 30(2), 187-95.

Nano aluminium particles were produced by wire explosion process (WEP) in nitrogen, argon and helium atmospheres. Thus produced nano particles were characterized through certain physico-chemical diagnostic studies using wide angle X-ray diffraction (WAXD) and by energy dispersive analysis by X-rays (EDAX). The size and shape of the powder were analysed by using transmission electron microscopic (TEM) studies. The particle size distribution studies were performed by adopting log-normal probability distribution. The relationship between size of the particle generated in the explosion process and the type of inert gas/pressure was analysed. The mechanisms of nano particle formation, the factors which can aid the process of formation of nano particle in the wire explosion process were analysed. It is realized that energy deposited to the conductor and duration of current flow have major impact on particles produced by this process.

4 tables, 9 illus, 14 ref

023734   Shaikh M A R;Sanghavi R R;Shelar S D; Chakraborthy T K;Amarjit Singh (High Energy Materials Research Laboratory, , Pune-411 021) : Feasibility study of processing estane-based LOVA gun propellant. Def Sci J 2007, 57(4), 557-62.

Low vulnerability ammunition (LOVA) propellant are currently being developed globally to replace all types of single-base, double-base and triple-base gun propellants, because LOVA propellants possess advantage like low vulnerability without compromising on ballistic properties. The objective of study is to establish processing of thermoplastic elastomer (TPE); estane-based LOVA gun propellant in cord/heptatubular geometry. Keeping in view various advantages of TPE such as simple processing, greater dimensional stability, lower production losses, superior insensitivity, and mechanical properties of the propellants, estane 5731 (polyurethane-ester-MDI, aromatic polyester) is selected for feasibility study as a binder in LOVA-based gun propellant composition, processed by solvent and semi-solvent methods and compared feasibility of processing as well as their evaluation wrt ballistics, vulnerability, and mechanical properties. The results indicate that gun propellants processed by semi-solvent method and extruded at elevated temperatures exhibit better ballistics, mechanical, and vulnerability properties.

^ssc5 tables, 10 ref

023733   Senthilnathan T (Physics Dep, Velammal Engineering College, Chennai-600 066) : Analysis of concentration of air pollutants and air quality index levels in the ambient air in Chennai city. J Instn Engrs-Pt EN 2007, 87(Mar), 3-7.

Weather can change from day to day or even from hour to hour. So it is necessary to give information regarding the condition of weather to the public by way of giving information about air quality. A key tool in this effort is the Air Quality Index or AQI. The Software for computing AQI has been developed by the user friendly 'Flash' language. During the period, January-December 2001, the concentration of primary air pollutants, SO₂, NO_X and SPM were observed from the sampling station, Vallalar Nagar (V Nagar) which was a traffic intersection sampling site in Chennai city. AQI values were also calculated using the concentration of primary air pollutants and the standard values recommended by National Ambient Air Quality Standards (NAAQS). Finally, the computed AQI values were compared with the rating scale to assess the degree of pollution in the ambient air. It is seen from the observations that the values of SO₂ and NO_X were well below the recommended values and the annual mean of suspended particulate matter (SPM) values were in the range of 287.85 μg/m³ and 317.25 μg/m³ which was very high when compared with NAAQS limits. Also the results were confirmed from AQI calculations.

7 tables, 8 ref

023732   Sengar S H;Kurchania A K;Rathore N S (NO, , ) : Design and development of composite solar water heater cum distillation unit for domestic use. Energy Fuel Users J 2007, 56(4), 23-7.

Composite solar unit of solar water heater cum distillation device (SWHD) was designed and developed for domestic uses to obtain hot water and distilled water simultaneously. The device was tested for full load condition in winter and summer to find out its performances. In solar water heater cum distillation unit the maximum temperatures of water in storage tank were 48.7°C and 58.3° C in winter and summer, respectively. Total distilled water in 24 hours produced from SWHD in February 2004 and April 2004 was 5007 ml/m²/day and 5275 ml/m², respectively. Efficiency of SWHD for winter and summer, respectively was found to be 36.70% and 27.65% for solar water beater, 49.55%, and 43,97% for distillation in winter and summer seasons.

5 illus, 4 ref

023731   Sekaran V;Rajagopal K (Civil Engineering Dep, A C College of Engineering and Technology, Karaikudi-630 004) : Comparison and modelling of zone settling data for industrial wastewater. J Instn Engrs-Pt EN 2007, 87(Mar), 13-17.

Settling of suspended biological solids are mainly done in thickeners. In this study batch settling tests were conducted using the activated sludge obtained from the sugar and tannery industries in a cylindrical thickener. Zone settling velocities were worked out for the entire batch settling tests and the logarithmic models were developed between zone settling velocity and suspended solids concentration. Zone settling comparison was made between the two industrial wastewater sludges. Solids flux curves were obtained for both industry wastewaters and limiting solids flux were obtained for different desired underflow concentrations. Models were developed for these underflow concentrations, the thickener areas, discharge, limiting solids flux and recycling ratios. These models can be used for the design of final clarifier treating sugar and tannery activated sludge.

4 tables, 4 illus, 3 ref

023730   Sarker B R;Diponegoro A (Industrial Engineering Dep, Louisiana State University, Baton Rouge, Email: bsarker@lsu.edu) : Finite horizon planning with fixed-interval deliveries and no shortage. Opsearch 2006, 43(4), 404-24.

Policy of raw materials and the manufacturing batch size for frequent deliveries of finished goods over a finite horizon play a significant role in managing the supply chain logistics economically. This research develops an ordering policy for raw materials and determines an economic batch size in a manufacturing system that supplies finished products to customers over a finite planning horizon. Fixed quantities of finished products are delivered to customers at a fixed interval of time. In this model, an optimal multi-ordering policy for procurement of raw materials and production cycle time for a production and supply system is developed to minimize the total cost incurred due to raw materials and finished goods inventories. A closed-form solution to the problem is obtained for the minimal total cost. A lower bound on the optimal solution is developed for the problem and the empirical tests indicate that the lower bounds are very close to the solution.

4 tables, 4 illus, 31 ref

023729   Ramana Murthy C V;Kulkarni S B;Singh B B (Finolex Academy of Management & Technology, , Ratnagiri-415 639) : Flow of an elastico-viscous fluid past an infinite plate with variable suction. Def Sci J 2007, 57(4), 549-56.

Unsteady state flow of an incompressible elastico-viscous fluid of second-order type past an infinite vertical porous flat plate by considering uniform and variable suction normal to the plate has been studied and an exact solution is obtained for the velocity field. In the present situation, only two prescribed boundary conditions are available while the governing equation of motion is of third-order due to the presence of elastico-viscosity parameter. The concept following Walters has been used for a much more meaningful solution. The results for the velocity distribution and skin friction have been analysed and discussed for different values of the parameters encountered in the governing equation of motion and skin friction on the plate. It is found that the effect of elastico-viscosity and suction has significant contribution on the backflow at the wall.

5 illus, 7 ref

023728   Qi Z;Kezhen W;Aimin L;Denggui W;Bin Q (NO, Beijing Institute of Technology, Beijing-100 081, People's Republic of China) : Numerical simulation on dispersal character of fuel by central HE. Def Sci J 2007, 57(4), 571-9.

Fuel-air explosive (FAE) device consists of a shell (top-end cover, bottom-end cover, shell-side wall), a mixed fuel, a central pipe and a burst high-explosive (HE) charged in the central pipe. The mixed fuel is filled in a column structure and dispersed by the explosion drive of central burst HE in the central pipe. The dispersed fuel mixes with air, which produces combustible cloud which can be detonated. That is the fuel-air explosive (FAE). The height and ignition position of the central HE charged column affect the fuel dispersal process. The initial stage of fuel dispersal was simulated by numerical computation. The simulation result indicated that the distribution of fuel dispersal velocity, when the central HE is ignited at the end, is not the same as that when the central HE is ignited on the axis of the central HE simultaneously. When the ratio of the column height of the central HE and that of the FAE device is 0.64<126>0.73, the distribution of fuel dispersal velocity has little difference when the central HE is ignited at the end of column. But, when the ratio of the column height of the central HE and that of the FAE device is 0.89, the fuel axial dispersal velocity is obviously more than that when the ratio of the column height of the central HE and that of the FAE device is 0.64<126>0.73.

^ssc9 illus, 10 ref

023727   Panwar S;Goel D B;Pandey O P (Metallurgical and Materials Engineering Dep, IIT, Roorkee-247 667, Email: dbgmtfmt@iitr.ernet.in) : Effect of cold work and aging on mechanical properties of a copper bearing microalloyed HSLA-100 (GPT) steel. Bull Mater Sci 2007, 30(2), 73-9.

Investigations have been carried out on the effect of cold work and subsequent aging on mechanical properties of a Cu-bearing HSLA-100 steel microalloyed with Nb and Ti. Aging at 400°C after various degrees of cold work (25-70 pct) exhibits multiple hardness peaks. The treatments cause significant improvement in hardness and tensile strength, but at the cost of impact strength. Cold work also causes deterioration in ductility, which again improves on subsequent aging. The C70A treatment involving 70 pct deformation exhibits maximum response to age hardening giving a hardness of 465 VHN and a UTS of 1344 MPa, but with low values of ductility (5 pct) and impact energy (24 J). C50A treatment involving 50 pct cold work and aging results in an optimum combination of mechanical properties. This treatment in the second hardness peak stage yields a hardness of 373 VHN, UTS of 1186 MPa together with a ductility value of 11 pct and impact energy of 109 J. Scanning electron microscopic studies of fracture surfaces reveal that the impact fracture occurs by formation of dimples and nucleation and growth of voids and cracks. Fracture in tensile specimens is caused by formation of voids and cracks at high density striations. Formation of voids and cracks is also assisted by the presence of precipitated carbide particles.

5 illus, 28 ref

023726   Mudgal A;Kapil;Mukesh Kumar;Ranvir Kumar (H & E Div, CSWCRTI, , 218-Kaulagarh Road, Dehradun-248 195) : Evaluation of irrigation practices for safe use of saline water under shallow water table conditions. Ann Biol 2006, 22(2), 143-8.

No country can afford to waste water or abandon ever-increasing land areas to salt. The challenge is making productive and sustainable use of salt-affected land, preferably by tapping the saline groundwater in the field. Basically there are two methods of irrigation with saline groundwater or drainable surplus viz., (i) Alternate or cyclic use of "low salinity" water with saline drainage water and (ii) Mix use of "low salinity" water with saline drainage water for irrigation. The option (i) is advocated by many researchers, but in the present study the option (ii) of irrigation was found more suitable. There was lesser salt build-up in the soil profile and also the crop yield was better with option (ii) of irrigation method.

3 tables, 1 illus, 11 ref

023725   Menq J Y;Tuan P C;Liu T S (NO, Kainan Univ, Taiwan, R.O.C.) : Conceptual lanchester-type decapitation warfare modelling. Def Sci J 2007, 57(4), 595-607.

Paper is based on the connotation of decapitation based on historical study and refines the term into military strategic concept of decapitation strategy. Ideas derived from detailed studies on Lanchester-type combat models are used to describe the effectiveness of conventional regular forces under decapitation warfare, which includes asymmetric, nonlinear, stand-off and special operation forces (SOF) operations. A conceptual model is presented to describe the effects of the decapitation strategy on the regular battlefield. With extensive coverage of operational factors such as robustness of ferces, time difference between combats, undermining effects, breakpoints, attrition rates, total force level and force allocation, the model is suitable to analyse complex scenario with different types of military operations consisting of decapitation strategy. An illustrative example is provided to demonstrate the application of the model. The-conceptual model is built based on hypotheses, assumptions, and criteria. In the absence of historical data, no data analysis and parameter estimation are involved.

1 table, 8 illus, 18 ref

023724   Manjaiah D H;Subramanya K N;Sharma S C (Post-Graduate Studies and Research in Computer Science Dep, Mangalore Univ, Mangalagangotri, Mangalore-574 199, Email: manju@mangaloreuniversity.ac.in) : Simulation and modeling of an automated system. J Analysis Computn 2006, 2(1), 77-83.

Simulation is an essential tool for performance evaluation of many practical systems where planners typically want to know how the system will perform under various parameter settings. Since large-scale simulation may require great amount of computer time and storage, appropriate statistical analysis can become quite costly. In this paper, an interpolation technique have been developed as an effective tool for estimating system responses to parametric perturbations in simulation. Analysed the usefulness of the M/M/1 model. The model sets no limit on the maximum number in the system. But it assumes an infinite-capacity source. Arrivals occur at the rate of e customers per unit time, and the service rate is μ customers per unit time. The result of the model consists of generation of Random numbers for the transition time and the system size, and the same is plotted on Graph which may vary depending on the random numbers generated. The model requires two basic elements. A chronological list of the model's events. A graph that keeps track of the changes in facility utilization and queue length.

3 illus, 8 ref

023723   Manjaiah D H;Subramanya K N;Sharma S C (Post-Graduate Studies and Research in Computer Science Dep, Mangalore Univ, Mangalagangotri, Mangalore-574 199, Email: manju@mangaloreuniversity.ac.in) : Automation manufacturing engineering policy in real time production technology. J Analysis Computn 2006, 2(1), 67-75.

To insure successful automation, it is necessary in good practice to define the overall functions and responsibilities of manufacturing engineering. Specifically, the responsibility for the design creation of a product should be that of the product design group. As a corollary, changes in the product character, whether they originate in or out of product group, should be made known to it and cleared by it. Similarly, since manufacturing engineers are responsible for automation, changes needed or brought about by the imperatives of automation should be fully discussed and explained by the. In the same way instructions of training of workers required by the new automation should clear through plant supervision early in the automation program. Infixing physical, electrical chemical, appearance, and safety characteristics, careful consultation between the product people and manufacturing engineers will help insure that the product can be economically developed. In order to make preliminary cost estimates, and arrive at a reasonable decision for action, it is usually necessary to agree or compromise as to the imperative attributes that can be accepted. This compromise between product specifications and a Reasonable production cost result becomes increasingly important as the use of highly automated production equipment grows.

5 illus, 10 ref

023722   Mandi R P;Kumar V S (NO, Central Power Research Institute, Visveswariah Univ, College of Engine, Sir C V Raman Road, Bangalore-560 080) : Integration of solar PV- disel hybrid power system. J Instn Engrs-Pt ID 2006, 87(May), 14-20.

Sizing of solar PV, DG set and battery bank Hybrid Power System (HPS) for different configuration for share of solar power has been described. Different configurations for integration of solar with diesel energy systems are explained in detail. The energy availability and economics of the integrated energy system are highlighted.

5 tables, 12 illus, 10 ref

023721   Maini A K;Bajaj S;Parmar A;Tiwari R;Sen N (Laser Science & Technology Centre, , Metcalfe House, Delhi-110 054) : FPGA-based signal processor for detection and interpretation of pulsed laser radiation. Def Sci J 2007, 57(4), 609-15.

Novel design technique for detection and interpretation of pulsed laser radiation implemented on Xilinx Spartan-III field programmable gate arrays (FPGA) is presented. The design architecture is modular with high performance and unparalleled flexibility that simplifies design changes. The design gives superior accuracy and scalability and is applicable to a range of FPGA technologies.

^ssc4 illus, 7 ref

023720   Mahanta A K;Dharmsaktu I;Pattnayak P K (Defence Research & Development Organization, SF Complex, , Jagdalpur-494 001) : Rheological behaviour of HTPB-based composite propellant: effect of temperature and pot life on casting rate. Def Sci J 2007, 57(4), 581-8.

Typical mix was carried out with 86 per cent solid loading and toluene diisocynate (TDI) as curator. Viscosity of the propellant slurry was measured at different shear rates over a range of temperature from 40 °C to 60 °C at various time intervals up to five hours from end of mix. The data are analysed using power law fluid equation to determine the viscosity index (K) and pseudoplasticity index (m). From these, optimum casting temperature and useful pot life was evaluated. Casting rates at different temperatures were determined by Haegen-Poisseuille equation modified for non-Newtonian fluid flow, using K and m.

2 tables, 5 illus, 18 ref

023719   Lahiri I;Balasubramanian K (Non-Ferrous Materials Technology Development Centre, , P.O. Kanchanbagh, Hyderabad-500 058, Email: indranil78@yahoo.com) : Application of mechano-chemical synthesis for protective coating on steel grinding media prior to ball milling of copper. Bull Mater Sci 2007, 30(2), 157-61.

One of the major sources of contamination during mechanical milling/alloying is from the surface erosion of the container and the grinding medium. This can either be prevented by using grinding medium and container of same material of the milled material or by adding a coating of the milled material on them. Describes the observations made during a mechano-chemical reaction, being used for coating the balls and vials in a planetary ball mill. Visual observation, XRD, optical micrography and EDS analysis were used to understand the progress of the reaction. Copper was successfully coated on the steel balls and vials. The method can easily be adopted in daily production purposes, prior to mechanical milling of a Cu-based powder for prevention of Fe contamination.

5 illus, 8 ref

023718   Khanra A K (Metallurgical and Materials Engineering Dep, IIT, Kharagpur-721 302, Email: asit_iitkgp@yahoo.com) : Production of boron carbide powder by carbothermal synthesis of gel material. Bull Mater Sci 2007, 30(2), 93-6.

Boron carbide (B₄C) powder has been produced by carbothermal reduction of boric acid-citric acid gel. Initially a gel of boric acid-citric acid is prepared in an oven at 100°C. This gel is pyrolyzed in a high temperature furnace over a temperature range of 1000-1800°C. The reaction initiation temperature range for B₄C formation is determined by thermal analysis. The optimal pyrolysis temperature of B₄C synthesis is investigated. During pyrolysis, the evaporation of boron-rich phases results in presence of free carbon in B₄C powder. The electron micrographs and particle size analyser reveal the generation of fine B₄C particles.

5 illus, 9 ref

023717   Kamali C;Pashilkar A A;Raol J R (National Aerospace Laboratories, , Bangalore-560 017) : Real-time parameter estimation for reconfigurable control of unstable aircraft. Def Sci J 2007, 57(4), 527-37.

Real-time open-loop parameter estimation of unstable/augmented aircraft is essential for reconfigurable/adaptive control. Describes two parameter estimation algorithms based on the equation-error minimisation principle. One is the recently developed, well-established recursive discrete Fourier transform (DFT) technique in frequency domain. The other is an application of recursive least square (RLS) in equation² error minimisation concept, applied to unstable/augmented aircraft parameter estimation. The RLS technique reported is implemented, for the first time, by a methodology that is analogous to the recursive DFT technique. Hence, in time domain, this can be viewed as a counter part of recursive DFT. The algorithms are implemented and tested for robustness against measurement noise. For the implementation, initially, data was generated under realistic conditions from simulation software that captures the dynamics of an unstable high performance aircraft, which is stabilised by full authority control laws. Subsequently, the algorithms are also tested with real flight data of a high performance unstable augmented fighter aircraft. The results bring out the merits of the algorithms and show their suitability for modelling of unstable aircraft, for subsequent adaptive/ reconfigurable control or fault diagnosis.

12 illus, 9 ref

023716   Kalra S (NO, , Holtec Consulting Private Limited, Gurgaon) : Sustainable management of land use in mining operations. Process Pl Engng 2006, 23(4), 42-4.

Management of land use and landscape associated with cement plants and mining operations is an important aspect of Sustainable Development. As cement companies recognise the need for more sustainable practices, if becomes essential that strategies be developed and executed for mitigating the environmental and social consequences of land use changes associated with all stages of the life cycle of a mine and of restoring the mining sites.

023715   Kallian R F (NO, ACC machinery Company Limited, Nagpur-441 122) : Most techno-economicaly viable clinker grinding system vertical roller pre-grinder plus ball mill system. Process Pl Engng 2006, 23(4), 54-6.

2 tables, 6 illus

023714   Jeyanthi J;Saseetharan M K (Civil Engineering Dep, Government College of Technology, Coimbatore-641 013) : Effect of MCRT on thickener area of secondary clarifier for treating dairy activated sludge. J Instn Engrs-Pt EN 2007, 87(Mar), 18-22.

Design and operation of suspended growth biological reactors normally are based on sludge age or mean cell residence time (MCRT). This paper extends mathematical modelling of secondary settling area for treating dairy wastewater with <113><255>_c, 10 days in stationary phase and 22 days in endogenous phase. Settling test data on the activated sludge were analyzed by modified solid flux analysis. The predicted models based on batch settling studies indicate that the area requirement to satisfy thickening criteria decreases with increase in MCRT.

4 tables, 3 illus, 6 ref

023713   Jeyanthi J;Saseetharan M K (Civil Engineering Dep, Government College of Technology, Coimbatore-641 013) : Biological treatability of dairy wastewaters - modelling of thickener area of secondary clarifier and development operational diagram. J Instn Engrs-Pt EN 2007, 87(Mar), 8-12.

From the stand point of activated sludge process design, the interactions between the biological aerator and secondary clarifier should be considered. This paper assumes that the secondary clarifier is to be designed for thickening. Therefore the task herein is to approach the functional design of the secondary clarifier by developing a mathematical model for thickener area. Based on the results of sedimentation tests conducted on dairy activated sludge for a Mean Cell Residence time of 11 days, a mathematical model was developed for thickener area determination, which depicts relationships between parameters that control efficiency of growth and substrate removal. The completely mixed activated sludge process has to be examined from the view point of process stability. Based on the thickener area arrived from the model and for the flow rate of waste water generated from the Dairy industry, an operational diagram was developed for a mean cell residence time of 11 days. The diagram can be used to design secondary clarifiers and to evaluate operational control options in response to changes in flow rate or solids settleabilty.

3 tables, 6 illus, 7 ref

023712   Jayachandran S S;Seshan V;Subramaniam T (Vel Sri Rangarajan Sakunthala, High Tech Engineering College, Chennai, Email: ssj1ht@gmail.com) : Wind turbine-generators for automobiles. Energy Fuel Users J 2007, 56(4), 1-6.

Attempt made to utilize the wind energy produced by the movement of the vehicle to generate electrical power. A description of the present 12V system for the power generation and also the use of 42V system for future loads are discussed.

6 illus, 2 ref

023711   Hazarika U M (NO, North Eastern Regional Institute of Water and Land Management, Kaliabhomora, P O Dolabari, Tezpur-784 027) : Flood environment in Assam and special reference to jiadhal basin of Dhemaji district - a critical review. J Instn Engrs-Pt EN 2007, 87(Mar), 23-7.

Flood, erosion and sedimentation are the chronic problems of Assam. The situation is worst in some of the river basins like Jiadhal basin of Dhemaji district. Heavy loss of resources occurs almost every year because of flood hazard prevailing in the region. But. the region is fertile and very rich in wafer and land resources as well as in agricultural potentiality. Therefore, the people continue to live in the area. Here the flood hazard scenario of the region is reviewed and analyzed and feasible management strategies are presented.

2 tables, 2 illus, 12 ref