008919   Singh S P;Mishra P;Singh S K (MCA Dep, Gandhi Institute of Computer Studies, Gunupur, Rayagada, Orissa, Email: drspsingh1@hotmail.com) : Estimation fo the reliability characteristics of a plate mill system of an integrated steel plant. Ultra Scient phys Sci 2009, 21(2M), 585-96.

Discusses the estimation of reliability characteristics of a plate mill system of Bhilai Steel Plant. The whole system consists of one reheating furnace two slab pushers, one horizontal stand and one finishing stands. Reheating furnace is used to reheat the slabs in order to convert them into specific sizes of plates with the help of slab pushers, horizontal stand and finishing stand. Slab pusher is used to push the red hot slabs towards the horizontal stand. Horizontal stand is used to cut the end of the red hot slabs and is used in expanding the length of slabs horizontally according to required length. Finishing stand gives final shape to red hot slabs. All the failure time distribution along with preparation time of reheating furnace and repair time of slab pusher where as all the other repair time distribution are taken as arbitrarily distributed. Using regenerative point technique, various reliability characteristics of interest to the system designers as well as for operation managers have been evaluated. Finally, some graphs are also plotted in order to highlight the important results.

4 illus, 7 ref

008918   Singh R N;Chakravartty J K;Banerjee S (Mechanical Metallurgy Section, Materrals Group, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Hydride induced embrittlement of zirconium alloy pressure tubes. BARC Newsl 2009, 309(Oct; spl), 71-89.

Tubes made of dilute Zirconium alloys, act as miniature pressure vessels in Pressurized Heavy Water Reactors (PHWRs) and are subjected to aqueous corrosion, resulting in hydrogen pick up. Hydrogen exceeding solid solubility, precipitates out as brittle hydride phase and may cause embrittlement of the host matrix. Two forms of hydride embrittlement have been recognized for dilute zirconium alloys - gross and localized. Gross embrittlement is caused due to uniformly distributed hydride precipitate, whereas localized embrittlement is caused by hydrogen migration, leading to damage accumulation within a small region over a period of time, before catastrophic failure of the component may occur. Parameters like fracture toughness, threshold stress for reorientation of hydrides, threshold hydrogen concentration for blister formation, Delayed Hydride Cracking (DHC) velocity, threshold stress intensity factor for DHC initiation, are used as fitness for service assessment of pressure tubes, in this article, some of the results generated by Materials Group, BARC, using Indian pressure tube material are highlighted.

14 illus, 1 table, 55 ref

008917   Shiva Prasad J S;Bhavsar T;Ghosh R;Narayanan G (Electrical Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: prasad@ee.iisc.ernet.in) : Vector control of three-phase AC/DC front-end converter. Sadhana 2008, 33(5), 591-613.

Vector control scheme is presented for a three-phase AC/DC converter with bi-directional power flow capability. A design procedure for selection of control parameters is discussed. A simple algorithm for unit-vector generation is presented. Starting current transients are studied with particular emphasis on high-power applications, where the line-side inductance is low. A starting procedure is presented to limit the transients. Simulation and experimental results are also presented.

33 illus, 11 ref

008916   Sharma S V;Nayak M M;Dinesh N S (NO, Indian Space Research Organisiation, Bangalore-560 094, Email: svsharma@isac.gov.in) : Shape memory alloy based motor. Sadhana 2008, 33(5), 699-712.

Design and characterization of a new shape memory alloy wire based Poly Phase Motor has been reported in this paper. The motor can be used either in stepping mode or in servo mode of operation. Each phase of the motor consists of an SMA wire with a spring in series. The principle of operation of the poly phase motor is presented. The motor resembles a stepper motor in its functioning though the actuation principles are different and hence has been characterized similar to a stepper motor. The motor can be actuated in either direction with different phase sequencing methods, which are presented in this work. The motor is modelled and simulated and the results of simulations and experiments are presented. The experimental model of the motor is of dimension 150 mm square, 20 mm thick and uses SMA wire of 04 mm diameter and 125 mm of length in each phase.

18 illus, 7 ref

008915   Sharma I G;Alex P;Bidaye A C;Suri A K (Materials Processing Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Electrowinning of cobalt from sulphate solutions. BARC Newsl 2009, 309(Oct; spl), 233-41.

Reports an account of study, conducted on optimization of the process parameters, for electro-winning of cobalt from cobalt sulphate solution. Effect of parameters such as bath composition, temperature, current density, agitation etc. on the voltage requirement, current efficiency and power efficiency of cobalt electro-deposition was explored. A maximum current efficiency of 97% was attained with an electrolyte composition of 60 g/L Co, 1 5 g/L Na_.2SO₄, at a temperature of 60°C, a pH of 4.0 and a cathode current density of 400 A/m². The energy consumption was 3.0 kWh/kg of Co deposited. The optimum conditions so established were test examined for recovery of cobalt values from leach liquors, generated on processing of Alnico magnet scrap, cemented carbide tool scrap and spent hydrogenation catalyst. The cathode current efficiency ranged from 86 to 94% due to lower concentration (25 to 40 g/L) of cobalt in the processed leach liquor.

9 illus, 1 table, 14 ref

008914   Sehgal V K;Alam M S;Arora M (NO, Punjab Agricultural Univ, Ludhiana, Punjab-141 004) : Agro processing complexes in rural Punjab. Indian Fmg 2008, 58(1), 32-3.

Agro-processing models based on resource availability in various agroclimatic zones in Punjab have been developed and validated. These models consist of two or more machines, i.e. mini rice mill (2.5 qph), baby oil expeller (60 kg/hour), small and large atta chakkis with scouring machine (50-500 kg/hour), masala grinder, cotton ginning machine, penja, cleaner, feed-making machine and dal cleaner for processing at farm/village level. The economic analysis of agro-processing complexes indicates that with an investment of Rs 650,000 on a mini rice mitt, baby oil expeller with filter press, atta chakki, flour mill, masala grinder and penja, a monthly profit of Rs 30,000 can be obtained, whereas with investment of Rs 100,000 on a mini rice mitt, penja and baby oil expeller, a monthly profit of Rs 7,000 apart from providing employment to 2-5 persons is obtained.

3 tables

008913   Sarkar D;Nayak D C;Das K (National Bureau of Soil Survey & Land Use Planning (ICAR), Regional Centre, Sector-II, Block - DK, Salt Lake, Kolkata-700 091) : Fertility capability classification of soils of Bankura district, West Bengal. Indian J Landsc Syst ecol Stud 2006, 29(1), 113-18.

The evaluation of fertility capability of the soils of Bankura district, West Bengal has been done by grouping the soils with same kind of problems from the view point of fertility management. The technique emphasizes quantifiable topsoil parameters as well as subsoil properties directly relevant to plant growth. The dominant soil series of 22 soil mapping units of the district has been assessed for Fertility Capability Classification (FCC) considering three categorical levels : type (topsoil texture), substrata type (subsoil texture) and the major modifiers relevant to the study area. Sixteen fertility capability units (FCC) have been identified and delineated in four major landforms in the district. The major soil constraints for crop production are dryness of the soils (ustic soil moisture regime), soil acidity, low cation exchange capacity, low exchangeable K and phosphate fixation due to high iron content and gravelliness in surface and subsoils. The FCC units will serve as the present fertility status of the soils and also at as the basis for conducting fertility related experiments in priority areas of the district.

1 illus, 2 tables, 6 ref

008912   Ramachandran A;Channa Reddy M;Moodithaya R (NO, Vemana Institute of Technology, Bangalore-560 034, Email: arama1947@yahoo.co.in) : Minimization and identification of conducted emission bearing current in variable speed induction motor drives using PWM inverter. Sadhana 2008, 33(5), 615-28.

Recent increase in the use of speed control of ac induction motor for variable speed drive using pulse width modulation (PWM) inverter is due to the advent of modern power electronic devices and introduction of microprocessors. There are many advantages of using ac induction motor for speed control applications in process and aerospace industries, but due to fast switching of the modern power electronic devices, the parasitic coupling produces undesirable effects. The undesirable effects include radiated and conducted electromagnetic interference (EMI) which adversely affect nearby computers, electronic/electrical instruments and give rise to the flow of bearing current in the induction motor. Due to the flow of bearing current in the induction motor, electrical discharge machining takes place in the inner race of the bearing which reduces the life of the bearing. In high power converters and inverters, the conducted and radiated emissions become a major concern. In this paper, identification of bearing current due to conducted emission, the measurement of bearing current in a modified induction motor and to minimize the bearing current are discussed. The standard current probe, the standard line impedance stabilization network (LISN)), the electronics interface circuits are used to measure high frequency common mode current, bearing current and to minimize the conducted noise from the system. The LISN will prevent the EMI noise entering the system from the supply source by conductive methods, at the same time prevents the EMI generated if any due to PWM, fast switching in the system, will not be allowed to enter the supply line. For comparing the results with Federal Communications Commission (FCC) and Special Committee on Radio Interference (CISPR) standards, the graphs are plotted with frequency Vs, line voltage in dBμ V, common mode voltage in dBμ V and the bearing current in dBμ A with out and with minimizing circuits.

15 illus, 15 ref

008911   Rajeev Kumar;Amritpal Kaur (NO, , ) : Use of internet in the engineering colleges of Haryana: an analysis. Int Libr Movement 2008, 30(3), 131-44.

Internet can be conceived as a rich, multi-layered, complex, ever-changing textual environment. The Internet provides several opportunities for the academic community. It is a mechanism for information dissemination and a medium for collaborative interaction between individuals and their computers without regard to geographic limitation of space. Content created on the Internet ranges from simple e-mail messages to sophisticated' documents' (sites) incorporating sounds, images and words. The Internet is a 'live', constantly 'moving', theoretically borderless, potentially infinite space for the production and circulation of information. The Internet is arguably one of the most significant technological developments of the late 20^{th century. It has emerged as a powerful educational tool. Today, engineering colleges are playing an important role in imparting technical education. The Engineers, who are the outcome of these colleges, require the latest and pin-pointed information in their respective fields. Due to high cost of engineering information resources, developing countries cannot provide these resources to their users. But Internet with the advantages, make the way for the developing countries to access information at a very low cost.}

9 tables, 7 ref

008910   Nutheti K M;Chippalakatti V S;Prakash S (NO, Centum Electronics Ltd, 44 KHB Industrial Area, Yelahanka New Town, Bangalore-560 064, Email: krishnamohan@centumelectronics.com) : Disign and development of high voltage high power operational amplifier using thick film technology. Sadhana 2008, 33(5), 713-20.

Applications of power operational amplifiers (opamps) are increasing day by day in the industry as they are used in audio amplifiers, Piezo transducer systems and the electron deflection systems. Power operational amplifiers have all the features of a general purpose opamp except the additional power handling capability. The power handling feature can be achieved using an external circuitry around a regular opamp. Normally power opamps can deliver current more than 50 mA and can operate on the supply voltage more than ±25 V. This paper gives the details of one of the power opamps developed to drive the Piezo Actuators for Active Vibration Control (AVC) of aircraft/aerospace structures. The designed power opamp will work on ±200 V supply voltage and can deliver 200 mA current.

7 illus, 3 tables, 4 ref

008909   Nandi S (University of Victoria, Department of Electrical and Computer Engineering, Victoria, BC, Canada, V8W 3P6, Email: snandi@ece.uvic.ca) : Space and time harmonics related problems and their mitigation for position and speed sensorless slip-ring induction motor drives applications. Sadhana 2008, 33(5), 565-80.

There have been renewed interests in slip-ring induction machines due to their increasing use in both grid connected and stand-alone wind power generation schemes. Despite the squirrel cage induction generators' advantages of being brushless, low-cost, needing less maintenance and having inherent overload protection, the biggest advantage of variable-speed wound rotor induction machines is in its doubled energy capture. Also in high power induction motor drives such as static Kramer drives or static Scherbius drives use of wound rotor induction motors is a must. Thus it becomes necessary to measure the speed of the machine for closed loop control for such high performance drives. Recently, a sensorless position and speed estimation scheme was proposed for wound rotor wind power generator. In this paper, the limitation of the scheme caused by space and time harmonics have been investigated. Simulation results have been presented to explain the mechanism of the space and time harmonics caused distortion of current. Experimental results showing the deterioration of speed detection scheme at light load for a slip-ring induction motor have been presented. Finally, improvements have been applied experimentally to obtain better speed estimation.

16 illus, 15 ref

008908   Murugan R;Nandakumar S;Mohiyadeen M S (NO, Bharat Electronics Limited, Nandambakkam, Chennai-600 089, Email: muruganr@bel.co.in) : DSP-based electric power assisted steering using BLDC motor. Sadhana 2008, 33(5), 581-90.

Introduces a design and implementation of electrically assisted power steering (EAS) using BLDC motor for a vehicle. The control architecture consists of two layers of control, namely the vehicle speed associated control and the torque assist control. In the higher level of control architecture, the vehicle speed controller works as an assistance level controller for the steering effort. In the lower level, the torque controller gives the effort level control. This has been realized by torque sensor and vehicle sensor interfaced in the DSP. For implementing in the system, a DSP-based BLDC motor controller with three-phase inverter module is specially designed using Hall-effect sensor feedback and a single de-link current sensor. This work is implemented in a Light Commercial Vehicle having a recirculating ball type gear. This is for the first time (EAS) being implemented for this type of vehicle any where in the world. Generally, EAS having clutch to disconnect the motor in high speed or abnormal conditions from the gear box. In this implementation the motor is directly coupled to gearbox without clutch and all abnormalities are handled by the processor. This is implemented without modifying the vehicle supply system like changing the existing alternator or rating of the battery and using the existing sensors. The design is such a way that the feel of the driver assistance can be varied easily at any time. The performance of the control system is experimentally verified and it is tested in one of the Light Commercial Vehicle (LCV).

11 illus, 9 ref

008907   Mukhopadhyay A K;Bhattacharyya S;Joshi K D; Rav A;Gupta S C;Biswas S (Mechanical Test Section, Analytical Facility Div, Central Glass and Ceramic Research Institute, Kolkata) : Characterization of alumina ceramics under shock loading. BARC Newsl 2009, 309(Oct; spl), 409-12.

This work reports the characterization of sintered Alumina ceramics, before and after shock loading, in a Gas Gun facility indigenously developed at BARC, Mumbai. The Nanoindentation technique was utilized, to reflect the decrease in. hardness and Young.'s modulus of Alumina ceramics due to shock loading. Detailed Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscopy (FESEM) was utilized, to understand the nature and degree of failure propagation and the interrelation between such damage evolution and the degradation in local mechanical properties, in these brittle ceramics. This study demonstrated for the first time, that shear stress dominated failure, could play a major role in damage evolution, in shock loaded alumina ceramics.

008906   Mukesh Kumar;Shahi D K;Nirmal Kumar;Pradhan S K (NO, , Diwakar Bhawan Mishratola, Gannipur, Muzaffarpur-842 001, Email: mukbihar@rediffmail.com) : Millimeter wave propagation through vertical layer of dust particles. Ultra Scient phys Sci 2009, 21(2), 355-60.

Deals with the propagation of millimeter wave through the layers of dielectric bodies. In order to obtain the expression for power loss each layer has been assumed as a dielectric wave guide tied with dielectric particles. Using the concept of electromagnetic wave propagation through a wave guide the expression for dielectric loss has been obtained. It has been found that the dielectric loss increases with increasing frequency and decreases with increasing visibility. It has been also found that the dielectric loss of the incident energy dependence heavily on particle size for different frequencies and visibility. In the lower range of the frequency the dielectric loss dominates over other losses, however at the higher range of the frequency the absorption loss has got its minimum value.

4 illus, 10 ref

008905   More D S;Kalluru H;Fernandes B G (Electrical Engineering Dep, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Email: dsmore@ee.iib.ac.in) : Design and analysis of full pitch winding and concentrated stator pole winding three-phase flux reversal machine for low speed application. Sadhana 2008, 33(5), 671-87.

Flux reversal machine (3FRM) is a doubly-salient stator permanent magnet machine with flux linkage reversal in the stator concentrated winding. The existing machines at low speed, low power (2-4 kW, 300 rpm) range are not economical. FRM topology is best suited for this application. An attempt has been made to improve the power density of machine by introducing full pitch winding. Full pitch winding FRM (FPFRM) has higher power density than the conventional concentrated stator pole winding FRM (CSPFRM). Design and comparative analysis of FPFRM and CSPFRM are made. Both machines are designed for 88.58 Nm and 300 rpm. Design details of both machines are presented. Finite Element Method (FEM) analysis is carried out to evaluate and compare the performance of CSPFRM and FPFRM. Series capacitive compensation is provided for better voltage regulation of both machines.

18 illus, 8 tables, 12 ref

008904   Meghwani A;Kulkarni A M (NO, Emerson Network Power (India) Pvt Limited, Mumbai-400 604, Email: anju.meghwani@emerson.com) : Development of laboratory model of SSSC using RTAI on Linux platform. Sadhana 2008, 33(5), 643-61.

Presents the implementation of Static Synchronous Series Compensator (SSSC) controller on Real Time Application Interface (RTAI) for Linux Operating System (OS). RTAI provides real-time capability to Linux General Purpose Operating System (GPOS) over and above the capabilities of non real-time Linux environment, e.g. access to TCP/IP, graphical display and windowing systems, file and database systems. Both Type II controllers, DC voltage and current scheduling controllers, are implemented in RTAI. To create a user friendly environment, Graphical User Interface (GUI) is developed in Linux OS in user space (non real-time) using a software available from Quasar Technologies (Qt). The controller is tested on a small scale laboratory model of a Voltage Source Converter (VSC) connected in series with a transmission line. The real time controller performs well in both inductive and capacitive regions.

18 illus, 19 ref

008903   Madhavan R;Ramanarayanan V (Electrical Engineering, Indian Institute of Technology, Bombay, Powai, Mumbvai-400 076, Email: madhavan@ee.iitb.ac.in) : Effect of annular secondary conductor in a linear electromagnetic stirrer. Sadhana 2008, 33(5), 689-98.

Variation of average axial force density in the annular secondary conductor of a linear electromagnetic stirrer Different geometries of secondaries are considered for numerical and experimental validation namely, 1. hollow annular ring, 2. annular ring with a solid cylinder and 3. solid cylinder. Experimental and numerical simulations are performed for a 2-pole in house built 15 kW linear electromagnetic stirrer (EMS). It is observed for a supply current of 200 A at 30 Hz the force densities in the hollow annular ring is 67% higher than the equivalent solid cylinder. The same values are 33% for annular ring with a solid cylinder. Force density variation with supply frequency and current are also reported. Numerical simulations using finite element model are validated with experimental results.

16 illus, 8 ref

008902   Madan Mohan Reddy K;Srimurali M;Neeraja D (Civil Engineering Dep, SKIT, Srikalahasti, Andhra Pradesh-517 644, Email: madankreddy@gmail.com) : Assessment of media characteristics in upflow aerated submerged fixe-bed reactors for the treatment of dairy wastewater. Ultra Scient phys Sci 2009, 21(2), 457-8.

Two different medias of Broken Granite Stones and Corrugated Pall Rings was installed in two reactors. Approximately 1250 mg/L of COD is applied at 24, 18 and 12 hours of HRT in progression continuously. The results imply that media porosity play a more significant than specific surface area.

008901   Lakshminarasamma N;Ramanarayanan V;Sidharthan P (Electrical Engineering Dep, Nitte Meenakshi Institute of Technology, Yelahanka, Bangalore-560 064, Email: lakshmipeg@yahoo.com) : New family of soft transition converters : design and dynamic model. Sadhana 2008, 33(5), 459-79.

Soft switching converters evolved through the resonant load, resonant switch, resonant transition and active clamp converters to eliminate switching losses in power converters. This paper briefly presents the operating principle of the new family of soft transition converters; the methodology of design of these converters is presented through an example. In the proposed family of converters, the switching transitions of both the main switch and auxiliary switch are lossless. When these converters are analysed in terms of the pole current and throw voltage, the defining equations of all converters belonging to this family become identical. Such a description allows one to define simple circuit oriented model for these converters. These circuit models help in evaluating the steady state and dynamic model of these converters. The standard dynamic performance functions of the converters are readily obtainable from this model. This paper presents these dynamic models and verifies the same through measurements on a prototype converter.

19 illus, 20 ref

008900   Kulshrestha A;Suresh Verma P V;Gupta A;Bhatt R B;Afzal M;Panakkal J P;Kamath H S (Advanced Fuel Fabrication Facility, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Laser welding of fully austenitic stainless steel (D9) thin walled tube with 316M austenitic stainless steel endplug. BARC Newsl 2009, 309(Oct; spl), 183-93.

The fabrication of fuel elements for Prototype Fast Breeder Reactor (PFBR), involves welding of fully austenitic stainless steel thin-walled clad tube and stainless steel 316M end plug. Pulsed TIG technique is generally used, for welding of clad tube and end plug. Laser welding has been introduced for end plug welding at the Advanced Fuel Fabrication Facility, BARC, Tarapur: Laser welding offers some advantages like low heat input, high speed, consistent penetration and bead geometry. In this paper, the effect of various laser welding parameters on penetration and bead geometry has been studied. Experiments were carried out by varying parameters like peak power, energy per pulse, spot overlap, welding speed, defocusing distance and repetition rate and their effect on bead geometry and penetration was determined. The process was modeled using Taguchi method and was validated experimentally. Based on the S/N ratio, the effect of each parameter on penetration and bead geometry was analyzed. The contribution made by each parameter in determining penetration and bead geometry was found using ANOVA. The results of Pulsed Nd-YAG laser welding were compared with Pulsed TIG welding of end plugs. It was found that laser welding gives consistent penetration and bead geometry as compared to pulsed TIG. The welds were characterized and the effect of parameters on microstructure was also studied.

11 illus, 9 tables, 6 ref

008899   Kulkarni S D (NO, Central Institute of Agricultural Engineering, Nabi Bagh, Berasia Road, Bhopal, Madhya Pradesh-462 038) : Developing entrepreneurship for soy food processing. Indian Fmg 2008, 58(1), 30.

Soybean contains about 40% protein, 23% carbohydrates, 20% oil and reasonable amounts of minerals, vitamins and dietary fibre. Soybean and its products are nutritious, economical and extend many health benefits. Supplementation of foods with 5-20% properly processed soybean in various traditional food recipes is recommended. Soybean can be utilized in the form of whole bean or after partially or fully de-fatting. However, due to the presence of some antinutritional factors, soybean requires careful processing before consumption. Soy foods made out of whole bean are wholesome, tasty, nutritious and preferred The utilization pattern of soybean in India is as seed uses (10%), direct food and feed uses (15%), oil extraction (75%). The major soy based food items are oil, nuggets (soy badi), soy milk, soy paneer, soy flour, soy-biscuit, soy based snack foods, etc.

008898   Krishnan M (Materials Science Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Shape memory alloys. BARC Newsl 2009, 309(Oct; spl), 19-24.

008897   Kedarnath S;Vasudevan K (Electrical Engineering Dep, Indian Institute of Technology Madras, Chennai-600 036, Email: kedar_news@yahoo.com) : Novel converter topology for TEM applications. Sadhana 2008, 33(5), 537-49.

Time domain Electro Magnetic (TEM) systems, are used for remote sensing of conductive mineral deposits buried under the surface of the earth. A low frequency trapezoidal current excitation set-up in an exciter coil loop causes a flux that penetrates deep into the earth. When the excitation is cut off sharply, conductive deposits in the earth carrying flux react by causing eddy current flows within them. The flux produced by such eddy currents is picked up by a sensor coil. By comparing the emf induced in the sensor coil with a priori known emf patterns for mineral deposits, the presence of mineral deposits can be ascertained. The voltage, current and energy levels of the TEM system, require special type of excitation technique. Power converters for such non-standard requirements are not reported in the literature, particularly for TEM applications. This paper introduces TEM systems to the reader and presents the requirements for excitation. A converter topology to meet the requirements, it's analysis, control and performance are presented. Among other alternatives that the authors have attempted, the topology presented features reduced number of passive elements, high voltage gain and low losses. These features enable the sensor head to be operated from the normal low level battery.

15 illus, 11 ref

008896   Gayathri N;Chandorkar M C (NO, 'A' Radar, Electronics and Radar Development Establihment, C V Raman Nagar, Bangalore-560 093, Email: ngayatri28@yahoo.co.in) : Design and implementation of FPGA-based phase modulation control for series resonant inverters. Sadhana 2008, 33(5), 505-22.

Owing to the tremendous advances in the digital technology, and improved reliability and performance of the digital control mechanisms, this paper focuses on design and implementation of digital controller using FPGA-based circuit design approach. The digital controller proposed is designed for series resonant inverter used in DC-DC converter applications. Phase modulation technique is proposed for the realization of digital controller on FPGA. The Series Resonant Converter (SRC) is considered in this paper as a preferred converter topology for high power, high voltage power supplies.Studies the implementation of phase shift modulation technique using FPGA. The inverter designed, is IGBT based, and Zero Voltage Switching (ZVS) technique is implemented due to reduced stresses on devices and increased efficiency. The phase modulated series resonant inverters (PM-SRC) promotes ZVS operation when its switching frequency is greater than resonant frequency. The designed PM controller is realized using FPGA on which control algorithm and other features of a controller are developed. The series resonant inverter is built and tested for full load under open loop and closed loop conditions at a switching frequency of 20kHz. The results are presented under varying load conditions. The simulation and the experimental results were found to match closely.

17 illus, 7 ref

008895   Borkar P A (College of Agricultural Engineering, Dr. Desmukh Krishi Vidyapeeth, Krishi Nagar, Akola, Maharashtra-444 104) : Value-additiono to organic produce a success story. Indian Fmg 2008, 58(1), 38-9.

Shri Deepakji Shinde has co-ordinated 1,500 farmers of Amravati, Nasik, Akola, Washim, Nagpur, Buldhana, Aurangabad, Ahamadnagar and Jalgaon districts of Maharashtra, Baitul district of Madhya Pradesh and Babar district of Gujarat. He brought about 6,070.4 hectare of land under organic farming. The efforts made by him resulted in registration of 54 agricultural commodities under organic certification by ECOCERT, Germany. The total production under organic farming by group of farmers co-ordinated by him was about 13, 000 tonnes during 2004-05. Out of this, the pulse production was about 1,250 tonnes and oilseed production was about 2,950 tonnes.

2 tables

008894   Borgohain A;Maheswari N K;Vijayan P K;Saha D; Sinha R K (Reactor Engineering Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Development of a high temperature oxygen sensor for lead bismuth eutectic. BARC Newsl 2009, 309(Oct; spl), 353-58.

7 illus, 5 ref

008893   Borghate V B;Suryawanshi H M;Dhomane G A (Electrical Engineering Dep, Visvesvaraya National Institute of Technology, South Ambazari Road, Nagpur, Email: vijay_borghate@rediffmail.com) : Analysis and performance of novel and highly efficient electronic ballast operating at unity-power-factor. Sadhana 2008, 33(5), 523-35.

Presents the electronic ballast, in which the coupling inductors are used to inject the current to the de-bus capacitors to boost the de-bus voltage and to filter out the ripples from input line current. The current injection coupling inductor injects its stored energy to the de-bus capacitors in every switching half cycle. Whereas, the boost coupling inductor keeps the de-bus voltage always above the peak of ac input voltage. Therefore, the proposed ballast maintains unity-power-factor and high efficiency with ripple-free input current over wide range of input line voltage in case of worst regulation. A symmetrical half-bridge inverter is used to drive the fluorescent lamps. The experimental results of the laboratory prototype ballast for 2 x 36 W fluorescent lamps operating at 50 kHz are presented.

4 illus, 9 ref

008892   Bhardwaj S;Borage M;Tiwari S (Electronics and Instrumentation Dep, Indian School of Mines Univ, Dhanbad-826 004, Email: shubhendu.bhardwaj@gmail.com) : Simplified loss analysis and comparison of full-bridge, full-range-ZVS DC-DC converters. Sadhana 2008, 33(5), 481-504.

The loss of zero-voltage-switching (ZVS) of active switches has been a serious limitation of full-bridge (FBZVS) converters. Many techniques have been proposed in the past to extend the range of ZVS operation over the wider and also the full range of operation. However, in these techniques ZVS is achieved at the expense of additional conduction loss in active switches and losses in the auxiliary components. In this paper, the analysis for the additional losses in various full-range FBZVS DC-DC converters and their comparative evaluation is reported. Closed form expressions are derived for average value of device currents and losses. The loss curves for various topologies are plotted and compared. The analytical results are found to be consistent with the experimental efficiency tests performed on 500 W, 100 kHz prototype. It is concluded that a recently proposed new topology has the least penalty of additional losses.

12 illus, 7 ref

008891   Behera R K;Das S P (Electrical Engineering Dep, Indian Institute of Technology, Kanpur-208 016, Email: ranjanee@iitk.ac.in) : Improved direct torque control of induction motor with dither injection. Sadhana 2008, 33(5), 551-64.

Three-level inverter-fed induction motor drive operating under Direct Torque Control (DTC) is presented. A triangular wave is used as dither signal of minute amplitude (for torque hysteresis band and flux hysteresis band respectively) in the error block. This method minimizes flux and torque ripple in a three-level inverter fed induction motor drive while the dynamic performance is not affected. The optimal value of dither frequency and magnitude is found out under free running condition. The proposed technique reduces torque ripple by 60% (peak to peak) compared to the case without dither injection, results in low acoustic noise and increases the switching frequency of the inverter. A laboratory prototype of the drive system has been developed and the simulation and experimental results are reported.

14 illus, 10 ref

008890   Aswal D K (Technical Physics and Prototype Engineering Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Hybrid nanoelectronics. BARC Newsl 2009, 309(Oct; spl), 1-18.

Area of hybrid nanoelectronics, wherein, organic molecules deposited on Si, exhib it electronic functionalities, is expected to extend the scaling limits of Si microelectronics down to a few nanometers. Discuss several issues pertaining to hybrid nanoelectronics and summarize the work done in this direction at our lab. Presents deposition of organic monolayers on Si substrates using self-assembly as well as electrochemical processes. The characterization of monolayers using various techniques to determine thickness, molecular ordering and orientation, surface coverage, growth kinetics etc., is presented. Finally, realization of molecular diode, resonant tunnel diodes and resistive memories based on appropriate architecture of monolayers, comprising of alkyl-chains (σ- chains) and conjugated molecules (π-moiety) is discussed.

15 illus, 1 table, 19 ref

008889   Anwar U M K;Paridah M T;Hamdan H;Bakar S E; Sapuan S M (Forest Product Div, Forest Research Institute Malaysia, 52109 Kuala Lumpur, Malaysia, Email: sapuan@eng.upm.edu.my) : Impregnation and drying process of bamboo strips treated with low molecular weight phenol formaldehyde (LMwPF) resin. J Polym Mater 2008, 25(2), 265-73.

Impregnation and drying process of phenolic treated bamboo strips with low molecular weight phenol formaldehyde (LMwPF) resin. A study was under taken to determine an impregnation process and suitable drying duration for phenolic treated bamboo strip at basal and middle portions of Gigantochloa scortechinii. The strips were impregnated using vacuum process. After treated with low molecular weight phenol formaldehyde resin (LMwPF) using different duration of soaking, the weight percent gain (WPG) of bamboo strips was measured. The weight percent gain (WPG) of the impregnated G. scortechinii (basal and middle portions) increases when longer soaking time. After 150 minutes of soaking, the WPG were 14% and 15% for basal and middle portions, respectively. The specimens were then dried in an oven for 3 to 12 hours at 60°C. The reduction of moisture content (Me) was plotted in a graph and analyzed. The suitable drying duration for bamboo strips were found to be between 6 to 9 hours. A significant difference (p<60>0.05) WPG was observed at middle portion but not within the basal portion. Moisture content of bamboo strips reduced with drying duration from average of 20% to 5%. However, the optimum drying duration should not exceed 9 hours after which the samples start to cupping. KEYWORDS: bamboo strips, low molecular weight phenol formaldehyde, impregnation, drying.

2 illus, 2 tables, 26 ref

008888   Agarwal S C;Paesler M A;Baker D A;Taylor P C; Lucovsky G;Edwards A (Physics Dep, Indian Institute of Technology, Kanpur-208 016, Email: sca@iitk.ac.in) : Bond constraint theory and the quest for the glass computer. Pramana J Phys 2008, 70(2), 245-54.

Electronic switching in amorphous chalcogenide semiconductors has been oliscrved and studied for nearly forty years. Technological exploitation of this phenomenon has most recently emerged in DVD's where GST, a compound of germanium, antimony, and tellurium, is used to store information. Explain show GST behaves as a switch and how X-ray absorption fine structure can be used' to unlock the specifics of the switching process. The tool that leads to this deeper understanding is the bond constraint theory and also explains how this theory leads to an explanation of switching and of the behavior and properties of amorphous materials in general. Finally, the prospects for developing GST-related materials into non-volatile memory media that could be the basis for glass computers are discussed.

7 illus, 1 table, 14 ref

006754   Zainudin E S;Siregar J P;Rashdi A A A;Sapuan S M (Mechanical and Manufacturing Engineering Dep, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia, Email: edisyam@eng.upm.edu.my ) : Design of an automatic egg cooker for boiled and poached eggs. J Fd Sci Technol 2008, 45(2), 170-2.

Automatic egg cooker (AEC) consists of various design core stages such as market investigation, product design specification, conceptual design and detail design. In each of these stages, design methods were used to support those activities such as brainstorming, Pugh evaluation and morphological chart. Eventually, the final concept selected was 10 eggs or can poach 5 eggs in a time. Aluminum coated Teflon was chosen as the suitable material for cooking rack and poaching pan. The base plate was aluminum, which is not subjected to corrosion. The new AEC can be used in restaurants and it is developed by looking into various total life cycle issues to achieve high quality product.

2 illus, 2 tables, 14 ref

006753   Yadav S K;Mahavir Singh;Rami Reddy S;Sarvjeet Singh;Reddy K P;Shaunak R;Mediratta R (NO, M/s Abhishek Industries Limited, Barnala-148 107) : Dusting and Lint reduction in AKD sized agro-based paper- An experience. IPPTA Jl 2008, 20(4), 133-40.

Conversion to Alkaline paper making with AKD size offers the Paper Maker an opportunity for improving the Product quality and system cleanliness, however we have experienced Dusting & Linting during offset printing on non-surface sized Wheat Straw-based Paper. The effect on surface strength of AKD sized paper may be due to more retention of fines & fillers with the use of high molecular weight low charge density Retention Aid polymer which is foremost requirement in AKD sizing as regards to retention of AKD is concerned. The present paper highlights the reduction in Dusting and Linting during offset printing in AKD Sized Paper by utilizing the concept of wet-end chemistry in choosing the correct wet-end chemical and its optimization. Based on feedback received from customer regarding the dusting, we studied the changes and trials were taken with Cationic Starch, DSR of improved cationicity & crosslinking agent in starch. Printing trials were taken on same sheet & web fed printing machine and found significant improvement in printability of paper. Number of prints were increased from 2500 to 6000 impressions in sheet fed and 5000 to 10000 impressions in web offset printing machine before cleaning the blanket. Printability, in regards to dusting, improved further on changing the bleaching sequence from conventional CE_PHH to ECF bleaching, OD₀E_OPD₁ i.e. 8000 in Sheet-fed & 12000 in web-fed. It was also experienced that residual Chlorine & high conductivity in pulp and hardness & TDS of water have detrimental effect on printability with respect to Dusting & Linting due to increase in Cationic demand.

7 illus, 5 tables, 4 ref

006752   Yadav K K;Singh P K (NO, Soil and Water Engineering Dep, AICRP on Groundwater Utilization, College of technology and Engineering, Udaipur, Rajasthan-313 001) : Groundwater recharge through percolation ponds in Rajasthan. Indian Fmg 2008, 57(10), 14-15.

Over exploitation of groundwater and lack of recharge has become an important aspect for meeting the ever increasing water demand. The groundwater resources can be augmented through artificial recharge and the success of recharge depends on the availability of good quality water, suitability of site and appropriate recharge technique. To respond the primary need of the people, recharging of aquifers through percolation ponds has become essential to check the declining rate of water table. The percolation ponds play a crucial role to augment the groundwater storage of arid and semi-arid regions of Rajasthan.

2 illus

006751   Verma A;Dhingra S;Soni M K (Institue of Instrumentation Engineering, Kurukshetra Univ, Kurukshetra-136 119) : Loss-less operation of IGBT based threephase voltage source inverter controlled through FPGA. Ultra Scient phys Sci 2008, 20(3), 575-80.

Comparative study has been made to find out the best operational advantages between MOSFET and IGBT based inverter. A suitable gate parameters of IGBTs has also been found out for its smooth conducting. FPGA as gate driver controller has been employed for controlling the ON-OFF operation of inverter to produce three phase at 120°. IGBT and MOSFET have been tested at 1000V to find out the on state resistance and load current bearing capacity.

4 illus, 14 ref

006750   Sachan A;Mehrotra V (Civil Engineering Dep, Indian Institute of Technology, Kanpur-208 0166eajantas@iitk.ac.in) : Evaluation of microfabric of clay using atomic force microscopy. Curr Sci 2008, 95(12), 1699-1706.

Term 'microfabric' (geometric arrangements of particles) was first used in the late 1960s to study features of the soil that cannot be seen with the naked eye; which includes the orientation of particles, particle size and shape, stratification and voids. It is generally believed that electron microscopy (SEM, TEM) is the only technique that can reveal particle arrangements directly. In the present study, a novel and more advanced technique, atomic force microscopy (AFM) is introduced to evaluate the microfabric of cohesive soil which is an important parameter to decide the shear strength behaviour of the soil. AFM has several advantages over SEM/TEM for characterizing particles at the sub-micron range: (i) AFM gives 3D images and 2D images with Z information, providing quantitative measurements of the soil microfabric using SPIP software; (ii) AFM images can be obtained in all environments - ambient air, liquid and vacuum. This article focuses on the use of AFM for evaluating the variation in particle size distribution, angle of orientation of particles, particle size and shape, and aspect ratio of particles due to the change in the microfabric of clay.

9 illus, 17 ref

006749   Rathore S S;Bhandari S (NO, Mining Engineering Dep, Maharana Pratap Univ, of Agriculture and Technology, Udaipur) : Controlling measures of damages due to various blasting techniques in splittable sandstone quarry during extracting. J Instn Engrs-Pt MN 2008, 88(Feb), 33-9.

Splittable sandstone is extracted in the form of blocks and cut into sized slabs to use in construction/ roofing: The uneven shape and crushed form of sandstone is mainly the waste material and has little application. Thus, extraction of sandstone in the form of blocks without damages at quarries has more value. Hence, experimental work in the quarries of sandstone was carried out for assessment of damages in the process of separa ting blocks by using detonating cord of 10 g/m to 30 g/m by varying hole spacing, hole diameter, air cushioning, water and sand filled blastholes. Blasthole notching was also carried out, Tests in the field were also carried out by using various slitted liners in sandstone formation. Results of experiments are analyzed in research paper for con trolling of damages and to improve the recovery of saleable product.

6 illus, 4 tables, 17 ref

006748   Ranjan S (NO, Civil Engineering Dep, National Institute of techbnology, Kurukshetra-136 119) : Hydraulics of jet aerators. J Instn Engrs-Pt MN 2008, 88(Mar), 29-32.

Exponential population growth and rapid industrialisation have increased the pollution load manifold on the disposal works of effluents. Aeration of wastewater has been a well-recognized technique used to continuously replenish oxygen economically and in sufficient amount, at the rate at which it gets utilized by the biomass. Aspirating aerators have been found to give high rates of oxygen transfer at low flows. High level of turbulence, resulting in better mixing and suppression of foam, are some of the added advantages of the aspirating typ'e of expansion aerators. Such type of aerators, though result in higher oxygen transfer at greater flows, are found to suffer from lower efficiency due to larger head loss. Jet aerators have been found to create large interfacial area and low head loss, resulting in higher oxygen transfer efficiency. In an effort to improve upon the jet aerator to achieve greater oxygen transfer, a modified device, named as an adjustable jet-spreading disc, was designed, fabricated and tested. The jet provided with the jet-spreading disc resulted in developing greater oxygen transfer efficiency. The limitation of development of lower efficiency at higher discharges in expansion aerators could be overcome with the help of the device tested, and a reasonably high efficiency and overall oxygen transfer factor at larger flow rates have been achieved. With an aim to optimise the design of jet aerator, tests were carried out using jet-spreading devices producing hollow conical divergent jets at three angles of impact of 30°, 45° and 60° on the water surface for flow rates of 2.31/s, 3.11/s and 3.61/s. Overall oxygen transfer factors and oxygen transfer efficiencies were observed to be better for 60°jet aerator. The maximum oxygen transfer efficiency of 4.01 kg/kW.h is achieved at a flow rate of 2.31/s and jet Froude number of 5.445.

8 illus, 11 ref

006747   Rai P;Choudhary B S (Mining Engineering Dep, Banaras Hindu Univ, Varanasi-221 005) : Firing pattern for generating free face in limestone quarry. J Instn Engrs-Pt MN 2008, 88(Feb), 3-8.

The case study pertains to generation of free face by the proper design of firing pattern for a limestone bench in a quarry in the Philippines. Due to operational circumstances, the bench was devoid of any free face. However, owing to the occurrence of high-grade limestone, it was essential to exploit limestone from the given bench. Given this backdrop, a suitable firing pattern was designed for the said bench after giving proper cognizance to some important blast design parameters, namely, hole-to-hole delay sequencing, effective spacing to burden (Se/Be) ratio, effective bench stiffness (H/Be), and judicious blast hole plugging with suitable plugging device. The field scale implementation of the designed firing pattern was conducted successfully to generate a slot, which was used as a free face for the subsequent blasts on the same bench for regular production of limestone. The results are tabulated, discussed and illustrated.

10 illus, 3 tables, 16 ref

006746   Rahman A;Ali A;Shrestha S (School of Engineering, Western sydney Univ, Locked Bag 1797, Penrith South DC, NSW 1797, Australia) : Life cycle cost analysis of natural channel as a componet of water sensitive urban design : a case study for the Cooks river in Sydney Australia. J Instn Engrs-Pt MN 2008, 88(Mar), 33.

Water sensitive urban design is an integrated approach of urban water management encompassing all aspects of an urban water cycle. Natural channel is an important component of water sensitive urban design but there has been limited research on long term financial viability of natural channels in urban environment mainly due to lack of long term field data.Explores the life cycle cost of natural and traditional concrete channels in the Cooks river in Sydney, Australia using some field and estimated data. At lower interest regime (for example, 5% to 9%), the life cycle cost of the natural channel appears to be slightly higher (by 4% to 6%) than the concrete channel. However, the differences in the life cycle costs of the two types of channels have reduced with increased interest rate and at about 17% interest rate their life cycle costs become very comparable.

4 illus, 5 tables, 8 ref

006745   Prabhakar A R;Raju O S;Kurthukoti A J;Vishwas T D (Pedodontics and Preventive Dentistry Dep, Bapuji Dental College and Hospital, Davangere-577 004, Email: attiguppeprabhakar@yahoo.com) : Effect of water purification systems on fluoride content of drinking water. J Indian Soc Pedodon Prev Dent 2008, 26(1), 6-11.

Purpose of the study was to determine the effect of different water purification systems on the fluoride content of drinking water and to compare the efficacy of these water purification systems in reducing the fluoride content. Five different water purification systems were tested in the study. They were reverse osmosis, distillation, activated carbon, Reviva, and candle filter. The water samples in the study were of two types, viz, borewell water and tap water, these being commonly used by the people of Davangere City, Karnataka. The samples were collected before and after purification, and fluoride analysis was done using fluoride ion-specific electrode. The results showed that the systems based on reverse osmosis, viz, reverse osmosis system and Reviva showed maximum reduction in fluoride levels, the former proving to be more effective than the latter; followed by distillation and the activated carbon system, with the least reduction being brought about by candle filter. The amount of fluoride removed by the purification system varied between the system and from one source of water to the other. Considering the beneficial effects of fluoride on caries prevention; when drinking water is subjected to water purification systems that reduce fluoride significantly below the optimal level, fluoride supplementation may be necessary. The efficacy of systems based on reverse osmosis in reducing the fluoride content of water indicates their potential for use as defluoridation devices.

2 tables, 12 ref

006744   Mukhopadhyay S K;Deb D (NO, Mining Engineering Dep, Indian Institute of Technology, Kharagpur-721 302) : Stope design below an abandoned open pit mine by 3d numerical modelling for a chromite deposit. J Instn Engrs-Pt MN 2008, 88(Feb), 16-24.

Summarizes the geo-mechanical investigations and numerical modelling analysis conducted in a developed underground chromate mining project in the Boula- Nuasahi area of Orissa. The mine was opera ted by open pit mining method. It has reached its economic depth and requires a major shift to underground mining for exploiting the remaining reserve. It is, therefore, necessary to understand the behaviour of the rock masses, in both the chromite ore body and host rocks. The objective of study is to design sub-level open stopes under a crown pillar below the abandoned open pit mine and analyze the stability of pillars in and around the stope during and after stoping using 3D finite element method (FEM).-To this end, the, results of the field observation and measurcements, complemented by laboratory testing are used as input parameters to build the realistic 3D FEM models of the open stopes situated below the abandoned open pit mine. Currently, the application of numerical analysis technique is gaining wide acceptance in the planning and design of underground mine structures. As a result, several attempts have been made to simulate the rock mass conditions using numerical modelling techniques to predict the rock mass response with the completed excavation geometry under various geo-mechanical conditions. The models explain the displacements, stress patterns, and influence zone in and around the stopes. To be realistic, the numerical models arc based on large geo-mechanical investigation data. Using Drucker-Prager failure criteria, specific conclusions have been drawn regarding the applicability, and usefulness of the design. Study clearly indicate that numerical models are extremely useful for a detailed understanding of the structural behavior of large mine excavations.

16 illus, 2 tables, 3 ref

006743   Minocha V K;Verma S;Saini G;Malhotra G (NO, Civil Engineering Dep, Delhi College of Engineering, Delhi-110 042) : Management of waste bentonite based slurry from drilling operations. J Instn Engrs-Pt MN 2008, 88(Mar), 38-42.

Investigates low energy, cost effective techniques for enhancement of solid content of the waste bentonite slurry from drilling operations. The mechanisms studied for achieving this objective were coagulation, ion exchange.and viscosity reduction. Conversion of the commercial sodium bentonite to calcium bentonite, which retains much less water, was found to be the-most suitable solution. This cation exchange was attempted by the use of calcium salts like gypsum, calcium chloride and lime. Of these, gypsum was found to be the most suitable. The simulated waste slurry samples were prepared to have 4% to 10% of bentonite by weight, as against the normal working range of 6% to 8%. A relationship was developed from the experimental data between the controllable variables, ie, the dose of gypsum, the initial percentage of bentonite in the slurry, the settling time and the percentage volume reduction. It is possible to achieve more than 50% volume reduction, thus considerably reducing the handling, disposal and management costs.

5 illus, 2 tables, 9 ref

006742   Katiyar V K;Katiyar A K;Srivastava S K (Brahmonand Post Graduate College, the Mall, Kanpur, Uttar Pradesh) : Empirical relationship of sixth order to estimate global solar radiation from hours of sunshine. J Agrometeorol 2009, 11(2), 97-101.

New set of constants based on sixth order polynomials fitting of measured data of sixteen Indian cities has been found to estimate the monthly mean global radiation on a horizontal surface. These constants provide good estimates of monthly mean global radiation on a horizontal surface with a maximum deviation of 8%. A comparison of the present result with the other models shows that the new constants yield more accurate results.

4 illus 4 tables, 11 ref

006741   Das A;Bhattacharya A (NO, ITC LIMITED-PSPD Unit:, Bhadrachalam Village: Sarapaka-507 128) : Impact of surface topography on print quality in online coated folding box paperboard. IPPTA Jl 2008, 20(4), 127-30.

Topography of a coated paperboard surface has been found to have substantial impact on the print quality parameters; particularly due to uniform absorption and splitting of ink. The nanoscale nature of threedimensional surface undulations in coating layer structure is known as surface topography and its impact have been observed by macroscopic visual evalutation of print quality. Explores firstly, the impact of various Coating recipe and Infra Red Drying of Coated Folding Box board on the topography of coated board surface. And secondly, the impact of topography or the microscopic undulations of coated paperboard surface on print quality.

3 illus, 9 ref

006740   Chakravarty D;Khatua S K;Ghosh S K (NO, , Minig Enginering Dep, IIT Kharagpur-721 302) : Advanced global and local thresholding techniques to rock images for fragment determination. J Instn Engrs-Pt MN 2008, 88(Feb), 25-32.

Introduces the rock image segmentation by global and local thresholding techniques, explains its -principles, advantages and drawbacks. After introducing six existing thresholding techniques, Otsu's thresholding technique and adaptive thresholding technique proposed by Yang and Hsu are implemented for gray level fragmented rock images obtained from open pit mine to deal with the poor contrast, non-uniformity and illumination noise. The general concept is explained in detail with examples and its usages for fragmented rock images. The computation time in adaptive thresholding method is less compared to that of Otsu's thresholding method. In applications on images of rock fragmentation, the advanced adaptive thresholding method would perform better for real-time scenario meaning that this method is better suited for handling complex data and uneven background illumination. It has also been noted that advanced adaptive thresholding method performs better for images having high noise ratio.

3 illus, 11 ref

006739   Aruna M;Karmakar N C;Rao Y V (NO, Mining Engineering Dep, NITK, Surathkal-575 025) : Lighting haul roads in surface coal mines- A design based on reflectance. J Instn Engrs-Pt MN 2008, 88(Feb), 9-15.

Highlights the significance of surface reflectance in the design of haul road lighting in coal mines. Lighting design has been made in coal as well as overburden benches taking 0.5 lux as minimum acceptable reflected light (instead of incident light) and 0.3 as reflected overall uniformity ratio. Design under wet condition would incur an excess cost of about 43.0 % for haul roads under study in coal bench and about 6.5% for overburden bench. It is apparent that the reflectance of the haul road surface plays a vital role in the optimum selection of light source and mounting height. reveals that the pole height decreases as the surface reflectance value decreases.

4 tables, 13 ref

006738   Ali N (NO, Indian Council of Agricultural Research, Krishi Anusandhan Bhavan-II, Pusa, New Delhi-110 012) : Promising farm tools and technologies for higher agricultural productivity and profitability. Indian Fmg 2008, 57(10), 19-26.

Engineering inputs facilitate higher agricultural productivity and profitability through timeliness in operations; better inputs-use efficiencies; minimizing post-harvest losses; use of renewable sources of energy; and reduction in drudgery of farm workers. Appropriate mechanization augment agricultural production by 10-15% and commodity specific post-harvest management could also add 5-10% more production by reducing losses. The potential for value-addition to agro-produce including crop-residues and byproducts is enormous, ranging from 25 to 400% depending upon the commodity and the level of processing. The article gives a brief account of some of the equipment, technology and products to illustrate the benefits of engineering interventions.

3 tables

006737   Alabi S B;Ikpatt F E (Chemical and Process Engineering Dep, Cenerbury Christchurch Univ, New Zealand, Email: uniquebola@yahoo.com) : Computer-aided simplification of high-order linear models. Indian chem Engr 2009, 51(2), 141-67.

Presents a very simple and effective computer-aided simplification (CAS) approach, the method of inequalities (MOI). For the past three decades, MOI has been applied to closed loop control system design, but not for solving model reduction problem. Hence, the work can be considered the first of its kind. A general multi-objective model reduction method is formulated for uncertain systems. The performance indices, which are defined as a set of algebraic inequalities, are defined as the sum of the squared errors between the output responses of the high-order uncertain systems and simplified uncertain systems. The simultaneous solution of these inequalities using moving boundaries process (MBP) in MATLAB environment yields stable optimal simplified models parameters. There is no need to monitor the stability of the reduced-order models during the course of iteration since the algorithm guarantees this. The effectiveness of the proposed approach is illustrated by means of three examples from the literature.

6 illus, 3 tables, 50 ref