018580   Mohanasundararaju N;Sivasubramanian R (Dep of Mechanical Engg., Sona College of technology, Salem-636 005, Email: mohanasundararaju@yahoo.co.in) : Combined artificial neural network and taguchi technique for selection of optimal process parameters in steel roll grinding. Mfg Technol Today 2007, 6(7), 11-17.

Deals with optimization of grinding parameters to obtain desired surface roughness in the work rolls using Neural Network-Taguchi approach. In this study, there are six factors wheel speed, work speed, traverse speed, infeed, dress depth and dressing lead were considered to obtain a optimum grinding condition using Taguchi Techniques with L₂₇ orthogonal array. An attempt was made to minimize the number of experimental runs and increase the reliability of experimental results. Artificial neural network (ANN) model was developed to enhance the prediction accuracy. The confirmation test was conducted to verify the results obtained from Taguchi Technique and Neural network model. Analysis of Variance (ANOVA) was conducted to identify the significant parameters during grinding process.

3 illus, 9 tables, 15 ref

018579   Mishra D P (Mining Engng Dep, IIT, Kharagpur-721 302) : Fly ash stowing in India - an emerging technology. J Mines Metals Fuels 2007, 55(5), 156-60.

Deals with the suitability of fly ash for stowing and brief case studies of fly ash stowing status of the above mines.

4 tables, 20 ref

018578   Mangalpady Aruna;Murthy C S;Pai K;Ramanand (Minging Engg Dep, NITK, Surathkal, Srinivasnagar-575 025) : Applications of computer in mining industry with special regard to shovel-dumper productivity. J Mines Metals Fuels 2007, 55(6-7), 191-4.

Addresses various optimization models available for productivity analysis of shovel-dumperjleer Match factor method is one of the commonly used techniques to know the relative coverage which shovels are getting Fom truck fleet. Operations research techniques like quelling theory, integer programming. simulation and goal programming consider the probabilistic nature associated with the system. Even though many models are available for optimization and analyzing the productivity of shovel dumper system, further research and study is needed to devise a desirable technique for the same.

1 illus, 21 ref

018577   Mahapatra A;Roy S S;Chatterjee A (NO, Central Mechanical Engng Res Inst, M.G. Avenue, Durgapur, Email: abhi_mahapatra@yahoo.co.in) : Virtual reality technology in manufacturing. Mfg Technol Today 2007, 6(9), 15-20.

Virtual Reality (VR) is well introduced and highly accepted in the, international society of institutional research. It is intuitively the correct man machine interface for all product design process stages. The application of VR in manufacturing possesses immense potential and challenges, both in the field of research and industrial applications. Manufacturing industry in particular the aerospace and automotive industry shares this excitement about VR. Research has provided a virtual manufacturing (VM) environment to these industries for simulating process design and reducing the cost. The potential future role of VR in manufacturing is discussed at the end of the text.

4 illus, 1 table, 19 ref

018576   Kumar A;Mondal P C (NO, Central Inst of Mining & Fuel Res, Barwa Road, Dhanbad) : Studies of significant properties of filter type self rescuer for its use in underground coal mine in CO exposure. J Mines Metals Fuels 2007, 55(10-11), 499-501.

The carbon monoxide (CO) is a highly toxic gas; it is outcome of fire or explosion in underground coal mines. It combines with hemoglobin of coal mine workers and carboxyhemoglobin forms which reduces the oxygen carrying capacity of blood. A few breath of CO gas, even 0.1 per cent in atmosphere, causes respiratory failure. Filter type self rescuer, FSR is a life saving gas mask breathing apparatus against CO exposure in underground coal mine. The quality of FSR was evaluated in respect of its duration for use, carbon monoxide conversion by hopcalite, breathing resistances, leak tightness properties, etc. A scope of improvement is observed in cartridge of self rescuer as well -as in the clauses of BIS 9563-1980 in order to increase the duration and improvement in the quality of self rescuer.

12 ref

018575   Kothari S;Sengar S H (Renewable Energy Sources Dep, Coll of Technol and Engng, Maharana Pratap Univ of Agric and Technol, Udaipur-313 001) : Performance evaluation of solar stills. Biomed 2007, 18(1-2), 35-7.

Component wise performance evaluation of multi wick solar still (MWSS) device developed at Department of Renewable Energy Sources, College of Technology and Engineering, Udaipur was carried out and compared with the performance single basin type solar still (SBSS). Overall efficiency of MWSS and SBSS were found to be 32.9% and 20.6% respectively. The yield of distilled water in MWSS device was varied from 3.9 to 4.17 ft./m² day where as in case of SBSS devise it was 2.4 to 2.71t./m² day from April to June. The physicochemical analysis was made to examine the effect of distillation on tap water. A drastic reduction in the TDS, Chlorides, Calcium hardness and Magnesium hardness, dissolved silica was observed through solar distillation.

1 illus, 1 table, 2 ref

018574   Khan R M K;Tripathi A;Krishna Reddy K (Resource Planning Dep, National Mineral Develop Corporation Ltd., Khanji Bhavan, Masab Tank, Hyderabad-500 028, Email: rmkkhan@hotmail.com) : Review of latest trends in gold exploration. J Mines Metals Fuels 2007, 55(8), 240-6.

There is a major shift in the percentage share of various leading gold producing countries since 1970. Republic of South Africa produced 67.70% of the total mined gold during 1970 which gradually came down to 17.30% during 2003. This is mainly due to shift in exploration strategy adopted by countries like Australia, USA, Canada, China, Peru, Tanzania, Ghana etc. Despite high demand, Indian gold production remains dismal whereas the fact is India also has considerable potential for new discoveries. A new approach to exploration integrating genetic models, remote sensing, airborne gravity along with ground geophysical and stream sediment surveys and GIS studies may give the desired results. These results should be further strengthened by fluid inclusion and stable isotopic studies. Recent technological advances in detection of lower gold values should also be adopted.

1 illus, 1 table, 26 ref

018573   Khambalkar V P;mahalle D M;Karale D S;Kamble A K (Unconentional Energy Sources and Electrical Engng Dep, Dr. PDKV, Akola, Maharashtra) : Development of solar water desalinizer. Biomed 2007, 18(1-2), 39-42.

Solar water desalinizer was developed in the laboratory. It was tested daily with and without reflector in the month of January and February, 2001 from 9 AM to 5 PM for its distilled water output at 1, 2 and 3 cm water depths. Using reflector, the output increased by more than 100 per cent. The output of the desalinizer without reflector varied from 0.44 to 1.26 I/day and that with reflector 1.56 to 2.36 I/day at different water depths. The output varied with solar radiation, time of the day and the water depth.

1 illus, 3 tables, 4 ref

018572   Khambalkar V P;Madansure V N;Gadge S R; Dahatonde S;Kamble A K (Unconventional Energy Source and Electrical Engng Dep, Dr. PDKV, Akola, Maharashtra) : Solar electric fencing on farm in Vidarbha region. Biomed 2007, 18(1-2), 57-60.

A survey was conducted to study the status of solar electric fencing in Vidarbha region. There are five places in Vidarbha region where this fencing is adopted. Out of these, three places were selected for the study. It has been observed that, two fencing were used for the protection of the farm from wild animals and remaining is for safety of soybean oil industry. Analysed the cost evolvement of the solar fencing. It was observed that cost of the solar fencing comes to Rs. 1.25 lakh per km length. This study reveled that, used of solar fencing enhancing the cropping pattern and hence increases the production of the farmer. It was also observed that farmers of this region grows crop like cotton, soybean, green-gram and orchard throughout the year by protecting farm through solar fence.

4 tables, 3 ref

018571   Kalbande S R;Mathur A N;Kothari S;Pawar S N (NO, Marathwada Agricultural University, Parbhani-431 401) : Design, development and testing of paraboloidal solar cooker. Karnataka J agric Sci 2007, 20(3), 571-4.

Present energy crisis scenario, it has become necessary to exploit new and renewable energy sources which are available locally at almost negligible cost. Among these an energy sources solar energy has an infinite potential and available at free of cost. For efficient utilization of solar energy, focusing type paraboloidal solar collector was designed and fabricated having aperture diameter of 1.3 m, depth of 0.30 m and focal length of 0.35 m. Maximum temperature of 326.45°C was obtained under no load conditions in bright sunshine hours of summer season. The thermal efficiency in clear bright sunshine day was found to be 26 per cent. The solar cooker was found useful in cooking a variety of food materials.

2 illus, 3 tables, 8 ref

018570   Kadam M S;Basu S K (Production Engg. Dept., Jawaharlal Nehru Engg. College, Aurangabad-431 006, Email: mdaskadam@rediffmail.com) : Optimization of the machining parameters in wire electrical discharge machining process using genetic algorithm. Mfg Technol Today 2007, 6(6), 10-15.

Illustrates the role of Binary Coded Genetic Algorithm to optimize the machining parameters viz: Duty Factor, Peak Current and Wire Speed in wire-Cut Electrical Discharge Machining Process to maximize the Cutting Speed. In present work, Single Pass Cutting of High Chromium High Carbon Die Steel material has been considered for the response parameters Cutting Speed and Surface Roughness. Determination of the generalized relationship of Cutting Speed and Surface Roughness dependant on the variable machining parameters of WEDM using adequate mathematical model basedon factorial Regression and ANOVA is done. Regression coefficient while formulating the relationship for Surface Roughness R_a and Cutting Speed CS are determined for three cases (blocks) taking Stratified Random Sampling. Parameters have also been analyzed for Sensitivity.

3 illus, 13 tables, 8 ref

018569   Jha U C (CII Technology Centre, Laxmi Devi Institute of Engg. & Technology, Alwar, Rajasthan, Email: uc_jha@yahoo.com ) : Lean manufacturing is essential for competitive advantage. Mfg Technol Today 2007, 6(6), 16-19.

Lean Manufacturing, best described as the relentless elimination of wate. The power of lean lies in its ability to reduce costs in all areas. this is accomplished not through traditional cost reduction efforts but by challenging every activity to determine if it adds value in the eyes of the customer. Lean manufacturing principles must be aligned rigorously and thoroughly at all levels of the supply chain to make a difference. Lean manufacturing will improve the performance in the form of dramatically reduced cycle times and inventories, enhanced supply chain throughput. This paper explains how to identify and analyze key processes, how to understand what needs to be fixed, how to know who should be involved, and how a successful implementation of lean manufacturing can save the Indian Manufacturing Industry which is going through a very tough time.

11 ref

018568   Jesuthanam C P;Kumanan S (Dep of Production Engineering, National Institute of Technology, Tiruchirapalli-620 015, Email: kumanan@nitt.edu) : Prediction of surface roughness in turning using RBFNN-FL technique. Mfg Technol Today 2007, 6(5), 22-7.

Surface roughness is an important aspect in evaluating the quality of a machined product and it is influenced by the machining conditions. conventional surface roughness measuring instruments are of contact type, offline and post processing in nature. Presently there is an increase in the demand for the use of intelligent techniques in manufacturing applications. In this paper a hybrid intelligent technique is presented by combining Radial Basis Function Neural Network (RBFNN) and Fuzzy Logic (FL) for the prediction of surface roughness in turning operations to achieve effective automation. A comparison is made between the use of RBFNN and hybrid RBFNN-FL technique.

3 illus, 2 tables, 11 ref

018567   Jayaraj V;Srinivasan K (K C G College of Technology, , Chennai-96) : Experimental investigation of journal bearing performance under dry conditions. Mfg Technol Today 2007, 6(5), 3-5.

Journal bearings are important type of fluid film bearings. Bearings without liquid lubricants find use in many areas from computer printers, toys to rocket engines. Dry bearings work with little or no liquid lubrication. Compared to rolling-element bearings, dry bearings are simpler to design, less expensive to purchase and maintain and they rsists contamination better. Though accelerated wear tests are used to investigate the performance of dry bearings. It is always considered `Gold Standards' to perform a physical text on the bearing concerned. In this study, tribological performance of 25% glass filled PTFE bearing is investigated. The tribological behaviours are studied based on the effects of sliding distance, bearing pressure and low and medium speeds.

4 illus, 5 ref

018566   Jatinder Kumar;Khamba J S;Mohapatra S K (Mechanical Engg Dep, AKGEC, Ghaziabad) : Ultrasonic machining of titanum-a state of the art review. Mfg Technol Today 2007, 6(9), 3-9.

Fundamental principles of ultrasonic machining; the modes and mechanisms of material removal and the effect of operating parameters on the performance indices-material removal rate (MRR), tool wear rate (TWR) and surface roughness are reviewed. The issues of production accuracy and precision in drilling deep holes have also been explored. A brief review on process application to the machining of titanium-considered as a tough material has also been presented. It has been concluded from the experimental study that ultrasonic machining could be applied effectively for machining titanium. When applied to titanium, ultrasonic machining results in low material removal rate (MRR), high tool wear rate (TWR) and low surface roughness.

6 illus, 1 table, 39 ref

018565   Gupta I;Gorai A C (Zool Dep, S.S.L.N.T. Mahila Mahavidyalaya, Dhanbad-826 001) : Impact of opencast coal mining on soil environment and its management. J Mines Metals Fuels 2007, 55(6-7), 195-200.

Opencast mining causes land degradation, land fragmentation, soil disruption, soil contamination, erosion and soil quality degradation. The contribution of opencast mining to total coal production around 350 million tonnes in India during 2003-04 was more than 75%. Mine spoils created due to opencast mining not fit for plant growth due to their high concentration of heavy metals and destruction of flora and fauna. Describes the procedures to improve the damage to the soil and improve the ability to support plant growth in long term. It also includes the practices of mine rehabilitation with emphasis on reªvegetation. The same can also be adapted in rejuvenation of mined out areas.

2 tables, 17 ref

018564   Gopala Krishna A (Dep of Mechanical Engg., J.N.T.University, College of Engg., Kakinada, Email: agopalakrishna@rediffmail.com) : Selection of optimal sequence of cutting tool positions on CNC magazines. Mfg Technol Today 2007, 6(7), 29-33.

Application of a newly developed global search technique, called ants-colony algorithm, for the quick identification of optimal index positions of cutting tools to be used on the tool magazines of CNC machines for executing a fixed set of manufacturing operations. Minimization of total indexing time is taken as the objective function.

2 illus, 3 tables, 7 ref

018563   Gopala Krishna A (Dept of Mechanical Engg, J.N.T. University, college of Engineering, Kakinada-533 003, Email: agopalakrishna@rediffmail.com) : Optimal selection of manufacturing operations sequence in CAPP. Mfg Technol Today 2007, 6(6), 4-9.

Computer aided process planning (CAPP) is an important interface between computer aided design (CAD) and computer aided manufacturing (CAM). CAPP in the past is typically a knowledge-based approach, which is only capable of generating a feasible plan for a given part. The present work involves the application of Differential evolution as a global search technique for a quick identification of optimal or near optimal operation sequences. Minimization of total number of set-up changeovers and tool changeoves is taken as the objective function. Initially, the given part is represented as an assembly of form features, with details of geometric specifications, tolerance and surface finish requirements. To produce each of the form features, the required machining operations are selected. Next, feasibility constraints are considered among various machining operations. The proposed method then finds the optimal sequences within the minimum possible time.

2 illus, 4 tables, 17 ref

018562   Gopala Krishna A (Dep of Mechanical Engg., J.N.T.University, College of Engineering, Kakinada-533 003, Email: agopalakrishna@rediffmail.com) : Optimization multi-pass turning operations. Mfg Technol Today 2007, 6(5), 6-10.

Selection machining parameters in any machining process significantly affects production rate, quality and cost of a component. Work involves the application of a newly developed global optimization technique called Differential evolution to optimize the machining parameters of multi-pass turning process. The optimal values of machining parameters such as number of passes, depth of cut in each pass, speed and feed are determined that correspond to the minimum total production cost subject to the technological constrainst of allowable speed and feed, surface finish, maximum cutting force and maximum cutting force and maximum cutting power of the machine tool. An example is taken from the literature to illustrate the proposed procedure.

1 illus, 3 tables, 18 ref

018561   Gauri S K;Chakraborty S (SQC & OR Unit, Indian Statistical Institute, 203, B.T.Road, Kolkata-700 108, Email: s_chakraborty00@yahoo.co.in) : Recognition of control chart patterns using feature-based artificial neural network approach. Mfg Technol Today 2007, 6(5), 11-16.

Controls charts usually exhibit one of the eight types of patterns. These patterns can be classified as normal and abnormal. Recognition of abnormal patterns in control charts can provide clues to reveal potential quality problems in the manufacturing processes. Neural network approaches (with features extracted from the pattern data as input vector representation) have been successfully applied by the researchers in recent years for recognition of control chart patterns. Usage of features leads to smaller network size and results in faster training and generally more effective and efficient recognition of control chart patterns. The reported feature-based approaches can only recognize six principal control chart patterns (CCPs). In this paper, a new set of features is proposed and a multilayered perceptron (MLP) neural network trained by back-propagation algorithm is presented that can recognize stratification and systematic patterns in addition to the other six patterns as mentioned above. Extensive performance evaluation of the developed pattern recognizer is carried out using simulated data. Numerical results indicate that the artificial neural network based pattern recognizer developed using the proposed set of features can perform well in real time process control applications.

2 illus, 4 tables, 17 ref

018560   Feskikaya S;Tuncdemir H (Mining Fac, Mining Engng Dep, Istanbul Technical Univ, Istanbul, Turkey) : Handy tool for every type of tunnelling roadheaders. J Mines Metals Fuels 2007, 55(12), 524-38.

Roadheaders have the distinct advantages over the conventional drill and blast system providing an uninterrupted operation and excavation. As a matter of fact they incorporate three functions: excavation, loading and transporting. They are versatile, relatively cheap, highly flexible, and can cut selectively. All these features make the roadheader very attractive. For long, coal producers remain much the most significant users of roadheaders. In fact, a decade ago the number was, for example, 2000 in Russia, more than 800 in UK and over 300 in Poland. Now, because of the growing demand for mechanized excavation in civil engineering, this sector also uses quite a number of roadheaders. Consequently, these machines are constantly being required to cut harder, more abrasive rocks than they were originally designed for. Another important requisite was being able to cut in one stationary position a minimum 70m² and even more cross section. The authors are not intended to give full information for neither roadheaders nor the rocks. Only some selected subjects for both of them are being dealt with.

23 illus, 13 tables, 27 ref

018559   Fang H;Zhixian S (Sci & Technol Univ, Fushun Mining Group, , China) : Research on water prevention and drainage system of fushun west open pit. J Mines Metals Fuels 2007, 55(12), 546-54.

6 illus, 5 tables

018558   Christu R;Asokan P;Kumanan S (Dep of Production Engg., National Institute of Technology, Tiruchirapalli-620 015, Email: r_christupaul@yahoo.co.in) : Facility layout design using particle swarm approach. Mfg Technol Today 2007, 6(7), 23-8.

Concerned with the application of the Particle Swarm Optimization algorithm to solve the problem of optimal facility layout in manufacturing system design. The general mathematical model available in literature is followed. The production flow data for varying number of products, machines and flow line are adapted for extensive application. The paper considers the different types of material flow patterns for the generalization of proposed method. The effectiveness of Particle Swarm Optimization is evaluated and compared with the benchmarked problems.

5 illus, 2 tables, 11 ref

018557   Chen Q;Wang H (Sch of Chem Engng and Technol, China Univ of Mining and Technol, Xuzhou, Jiangsu-221 008, P.R. China) : Establishing large-scale pithead power station using two-stage high efficiency dry coal cleaning system before coal burning. J Mines Metals Fuels 2007, 55(12), 563-8.

Based on the analysis of economic development and energy structure in China, points out that coal still is the primary energy resource in first twenty years of this century in China. Analyzing the current serious problems of coal utilization indicates that coal can be prepared high efficiently before burning. And the best solution to realize the optimum configuration of coal production and consumption is to establish large-scale pithead combined heat and power plants with Chinese characteristics.

6 illus, 2 tables, 15 ref

018556   Brahma K C;Pal B K;Das C (NO, Central Mine Planning & Design Inst, Bhubaneswar-751 001) : Study on application of markovian decision process in drilling and blasting operation of opencast mines. J Mines Metals Fuels 2007, 55(1-2), 24-9.

Indian mining industry today stands at a critical juncture looking for new directions of growth and improved competitiveness. Technological change continues to trigger change in industry as it grapples with problems of technology diffusion. There is a quantum jump in opencast mining production due to tremendous change in mining machine design. Drilling and blasting plays a vital role in opencast mining. It not only affects the cost of production directly but also influences the overall operational cost significantly. Lots of emphasis is being given on the optimum blast design to get uniform blast fragmentation with designed level floor so that the loading operations are swift and simple and less breakdown of the handling equipment. Thus, the success or failure of drill and blast methods cast a long shadow over the balance of the operations. Authors have attempted to develop models on drilling and blasting operation based on the Markov chain techniques. This technique has been found to be very effective in modelling other operational sub-tasks like charging and loading in opencast mining operation.

2 illus, 10 ref

018555   Biswas S K (Mechanical Engineering Dep, Indian Institute of Science, Bangalore-560 012) : Friction and dissipation in surfaces functionalized by Organic monomolecular assemblies. J Indian Inst Sci 2007, 87(1), 15-34.

Genesis of friction in self assembled monolayers is reviewed. Application of traction to these monolayers generates translational and rotational motions at the level of chemical bonds which disturb the crystallographic symmetries and generates disorder. On unloading these stored energies are dissipated. The more the avenues of energy dissipation higher is the frictional resistance. The frictional work equilibrates with the total energy that can be dissipated. We review the experimental and theoretical basis of this understanding and explore the dissipation mechanism experimentally. We conclude tha translational motion, initiated almost instantaneously on contact, is purely elastic in character and consists of collective tilt and bending of molecular backbones accompanied by bond stretching . This is followed by viscoelastic rotational motions which generate gauche defects. The latter process is only partially reversible. The latterintroduces a time element into the frictional response which we demonstrate is related to the ratio of contact intermittency which is a function of velocity and stroke length and relaxation time which is a function of the applied pressure and the molecular configuration of the monolayer.

^iia22 illus, 58 ref

018554   Biswas A K (NO, , CBM-BPM Basin, ONGC, 50 J. L. Nehru Road, Kolkata-700 071) : Coalbed methane - the emerging source of fossil fuel. J Mines Metals Fuels 2007, 55(3), 54-8.

5 illus

018553   Bhattacherjee A (Mining Engng Dep, I.I.T., Kharagpur) : Injury prevention and control in mines through epidemiological approaches. J Mines Metals Fuels 2007, 55(12), 569-75.

Preresents some of the techniques used in epidemiological studies and illustrates their application in the evaluation of various risk factors associated with injuries in coal mines.

5 illus, 3 tables, 24 ref

018552   Bhattacharya J;Cheong Y W (Geo-Envir Lab, Mining Engng Dep, Indian Inst of Technol, Kharagpur-721 302, Email: jayantab@mining.iitkgp.ernet.in) : Insights into microbiogeochemistry of iron cycle in acid mine drainage. J Mines Metals Fuels 2007, 55(12), 555-62.

Presents a review of the presence and role of different bacterial population in iron cycle with special to reference to acid mine drainage (AMD)-from generation to precipitation/resolubilization. Interesting new researches claim that the bacterial groups exhibit preferences for their habitation in mine water at different reduction and oxidation states as well as on the state of metals enrichment. The results are important because these findings will help us in finding the new biotechnological solutions for bio-leaching, and in the development sustainable technologies of mine water treatment. The discussion here revolves around the iron water pE-pH diagrams and where in them, microbes play their role.

8 illus, 19 ref

018551   Bhat N (Dep of Electrical Communication Engineering, Indian Institute of Science, Bangalore-560 012, Email: navakant@ece.iisc.ernet.in) : Nanoelectronics era: novel device technologies enabling systems on chips. J Indian Inst Sci 2007, 87(1), 61-74.

Complementay Metal Oxide Semiconductor (CMOS) transistors in sub-100 nm regime are reviewed. The non-classical CMOS device technologies such as high-k gate dielectics, strained silicon channel, Silicon On Insulator, multi-gate transistors, and metal gate electrodes, are discussed in detail. These techniques are expected to scale the CMOS devices to an ultimate limit of 5 nm physical gate length. The system level issues of growing power dissipation and increasing device to device variability in the chips should be overcome for the successful realization of complex systems in nanoelectronics technologies. A brief overview of the non-CMOS memory and logic device architecture is provided. The opportunities in building hybrid systems on chips by combining sensors and actuaors along with the compute and storage functions on a single chip are described.

^iia16 illus, 59 ref

018550   Bhat K N (Dep Indian Institute of Science, , Bangalore-560 012) : Silicon micromachined pressure sensors. J Indian Inst Sci 2007, 87(1), 115-31.

Silicon micromachining for realizing micro mechanical structures has received considerable interest due to the several advantages of this technology over the conventional machining techniques. Silicon pressure sensors were the first micro mechanical transducers developed. Since thenthe market for micromachined pressure sensors has grown in leaps and bounds and found application in all walks of life including defense and spaceapplications. The relevant micromachining technology and the design considerations are reviewed in this paper. The paper also gives the latest developments in this area and gives the details of the polysilicon piezoresistor based pressure sensors with Silicon On Insulator (SOI) approach for integrating pressure sensor and associated electronics.

^iia19 illus, 4 tables, 27 ref

018549   Bandyopadhyay D (NO, Inst of Drill Technol, ONGC, Dehradun) : Progress in drilling fluids to its present state-of-art technology. J Mines Metals Fuels 2007, 55(3), 64-7.

Drilling fluid plays a very vital role in any drilling programme. Traditional saying is that drilling fluid is the blood of drilling a well. To carry out itsfill1ctionsfor drilling shallow wells to hi-tech, extended reach horizontal wells few thousand metres below the surface, drilling fluids have evolved from a simple medium to high performance systems. Water, oil and also gas have been used as base for single component or multi-component fluid systems. Functions, chemistry as well as the development of the systems from state of early days to its present state-of-art technology have been described.

3 illus, 6 ref

018548   Aziz N;Jalalifar H (NO, Shahid Bahonar Univ of Kerman, Iran) : Role of profile configuration on load transfer mechanism of bolt for effective support. J Mines Metals Fuels 2007, 55(12), 539-45.

Bolt profile is one key factor in load transfer capacity of rock bolt system. A series of laboratory based push and pull tests were carried out to investigate how profile configuration influence the load transfer mechanism of bolt/ resin interface. Tests were carried out in both 75 mm and 150 mm long steel sleeves. Three types of bolts were examined, they were bolts most commonly used for strata reinforcements in underground coal mines in Australia. The bolts had near equal core diameter but of different profile configurations. The change in the length of the encapsulation sleeve was examined in light of the small number of profiles encapsulated effectively in short 75 mm long sleeves. The results showed that peak loads and displacements were directly related to the height and the spacing of the bolt surface profiles. Profile spacing appears to have greater influence on load transfer capacity than the profile height.

20 illus, 2 tables, 14 ref

018547   Ayappa K G;Malani A;Kalyan P;Thakkar F (Dep of Chemical Engineering, Indian Institute of Science, Bangalore-560 012) : Molecular simulations:probing systems from the nanoscale to mesoscale. J Indian Inst Sci 2007, 87(1), 35-60.

Review is concerned with the role that molecular simulations have played in enhancing our understanding of systems ranging from the nanoscale to mesoscale. The structure and dynamics of nanoscopically confined films, fluids confined in carbon nanotubes, self assembled monolayers and mesoscale simulations of a variety of complex fluid systems using dissipative article dynamics, are covered in this review. Molecular simulations have significantly enhanced our understanding of confined fluid behaviour and self assembled monolayers, aiding in the interpretation of experimental findings on these systems. The science of these systems influences our evaluation of interfacial processes such as freezing, adsorption, wetting, adhesion, friction and lubrication, impacting a wide range of technologies ranging from fluid separations, sensors, microelectromechanical (MEMS) devices to nanofluidic systems. The last part of the review concenrns the study of mesoscale systems, where length and time scales of the processes are typically greater than those sampled in conventional molecular simulations (1-10 nm, 1-10 ns). The emphasis is on a relatively new technique called dissipative particle dynamics and its potential in studying complex fluid phenomenon, from self assembly in oil-water-surfactant mixtures, polymer structure and rheology to continuum fluid mechanics.

^iia7 illus, 239 ref

018546   Ansari A R;Paramasivam R (Neyveli Lignite Corporation Ltd, , Neyveli-607 801, Email: ansari.ar@nlcindia.com) : Development of mining system at Neyveli. J Mines Metals Fuels 2007, 55(4), 90-7.

5 illus

018545   Ankaliki S;Kulkarni A D;Ananthapadmanabha T (Electrical & Electronics Engng, S.T.J. Inst of Technol, Ranebennur-581 115, Email: sankaliki@rediffmail.com) : Artificial neural network based transient security assessment of power system. J Analysis Computn 2007, 3(2), 115-26.

In post fault dynamic analysis of interconnected power systems, the critical fault clearing time (CCT) is one of the parameters of paramount importance. It constitutes a complex function of the pre-fault system conditions, fault type, locations and protective relaying strategy. The evaluation of CCT involves elaborate computations that often include time-consuming solutions of non-linear on fault system equations. An Artificial Neural Network (ANN) based method of fast prediction of CCT variations is presented in this paper. Due to high capability of parallel information processing of ANN, the proposed approach is fast and accurate. Outcomes of this approach help the power system operator to successfully handle the topologically independent transient security assessment process.

6 illus, 2 tables, 5 ref

018544   Adhikari G R (NO, National Inst of Rock Mechanics, Kolar Gold Fields 563 117) : Ground vibration and structure response due to rockbursts at kolar gold fields, India. J Mines Metals Fuels 2007, 55(5), 145-52.

Even though the underground mines of Kolar Gold Fields, India, have been closed, rockbursts continue to occur. Some of these rockbursts are strongly felt in the mining township, causing concerns to local residents. Ground vibration induced by rockbursts and response of a building were monitored continuously for a period of five months. The observed vibration characteristics were compared with the permissible limits specified by the Director General of Mines Safety. The study revealed that the ground vibrations induced by the rockbursts were low to cause damage to surface structures.

6 illus, 3 tables, 8 ref

018543   Abdolhadi Ghazvinian (Mining Dep, Fac of Engng, Tarbiat Modarres Univ, Tehran, Iran) : Overview of mining industry in Iran, new technological changes. J Mines Metals Fuels 2007, 55(1-2), 3-10.

1 illus, 12 tables, 6 ref

017640   Venkatesh G;Ramachandra A (NO, Sasken Communication Technologies Ltd, 139/25, Domlur, Bangalore-560 075, Email: gv@sasken.com) : Can 3G technologies benefit rural India?. Indian J Radio Space Phys 2007, 36(3), 172-7.

To increase telecom penetration into rural India, we would need low cost options for networks and devices that provide support not only for voice services, but also for rich media and higher data rate services. Examines whether the evolution of GSM (Global System for Mobile communication) into 3G and HSDPA (High-Speed Downlink Packet Access) could enable this transformation, since this provides higher peak data rates and also significantly increases the network capacity. The problem is that 3G devices and services are typically part of the premium (high-price) services in the developed countries, while they have to be offered at very affordable prices if they have to take off in the rural areas. A paradigm shift may thus be required to resolve this paradox. In this paper, the authors examine if low cost 3G and HSDPA is really feasible.

017639   Vanhoenacker-Janvier D;Oestges C;Martellucci A (Microwave Lab, Universit‚ catholique de Louvain, Louvain-la-Neuve, Belgium, Email: vanhoenacker@emic.ucl.ac.be) : Scintillation and depolarisation models for satellite communications in the 20-50 GHz band. Indian J Radio Space Phys 2007, 36(5), 369-74.

Presents improved methods for the prediction of cumulative distribution of scintillation variance, using radiosonde data. This method has the advantage of being usable all around the world and its accuracy is improved with respect to classical methods based only on ground measured data. The second part presents a two-layer depolarisation model separating rain and ice effects for better scalability.

017638   Singh P;Raja Kumar R V;Lamba T S (Electronics & Electrical Communication Engineering Dep, Indian Institute of Technology, Kharagpur 721 302, Email: psingh, rkumar, tsl@ece.iitkgp.ernet.in) : Novel multiple access scheme for mobile communications systems. Indian J Radio Space Phys 2007, 36(5), 430-35.

Presents a novel multiple access scheme for future mobile communications using Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA) and Code Division Multiple Access (CDMA). The proposed system can support different classes of users each with different data rates and can provide very high spectral and system efficiency for the uplink and downlink. It is able to meet the demands on flexibility in data rate and provides scalability with respect to bandwidth using variable time slots, spreading factors and number of subcarriers. It exploits the advantages given by the combination of the spread spectrum technique with multicarrier modulation as well as TDMA.

017637   Shapira J (Electrical Engineering Dep, Indian Institute of Technology, Chennai-600 036, Email: jshapira@comm-and-sens.com) : Cost-effective mobile communications for developing economies. Indian J Radio Space Phys 2007, 36(3), 182-7.

Optimization of the radio access is a major challenge for a mobile wireless communications system, where both the channel and the multitude of users are not known exactly. The classical cellular architecture provides only rough guidelines, and at the same time, propagation modeling, statistics, and network simulations, fall short of representing and optimizing the actual network performance. Cost-aware Wireless Access Optimization (WAO) governs the radio coverage at the base stations and additional RF access points (repeaters) as required by the environment and traffic demands. Optimal performance is achieved by combining prediction models with dynamic measurements, and applying coverage and diversity means accordingly. The optimization of the new data-optimized systems - 1xEV-DO and HSDPA do not follow the same pattern, and a completely different optimization paradigm has to be taken when mixed services operate on the same network. These techniques and the corresponding benefits experienced in practical deployments are reviewed. Major savings in infrastructure costs have been shown, both in rural and in congested urban areas. The developing economies may take the leading role in developing WAO, due to their cost-awareness, fast development of networks, and the keen interest to enhance the domestic value of the systems and the service.

017636   Saikia N M;Tiru B;Boruah P K;Boruah K (Physics Dep, Gauhati University, Guwahati-781 014, Email: nayan075@yahoo.co.in) : Search for radio signal associated with UHE cosmic ray air showers in VLF range. Indian J Radio Space Phys 2007, 36(5), 436-39.

Experimental studies on the possibilities of detection of radio emission from ultra high energy cosmic ray (UHECR) extensive air shower (EAS) are done with the help of loop antenna system in the LF/VLF region. The signals from the loop for different orientations are analyzed off-line. The antenna is operated in coincidence with the particle detectors of mini-array to select the radio pulses originated from UHECR EAS. The experimental arrangement and important conclusion are discussed.

017635   Ramprasad A V;Meenakshi M (Electronics and Communications Engng Dep, Coll of engng - Anna Univ, Guindy, Chennai-25) : Suppression of four wave mixing crosstalk components - a comparative study between genetic algorithm and optical orthogonal codes. J Optics 2007, 36(2), 68-77.

Increase in the data rate of fiber optic communication systems limited due to the nonlinear effects like Self phase modulation(SPM), Cross phase modulation(XPM) and Four wave mixing (FWM). Many investigations are carried out to mitigate these effects. In multi channel systems, Four wave mixing (FWM) in optical fibers induces channel cross talk and possibly degrade system performance. An optical orthogonal code is the family of(01) sequence with good auto and cross correlation properties. It has been found in the literature that the FWM crosstalk components can be suppressed by the unequal spacing of the multiplexed channels. This unequal and equal spacing of the channel and frequency allocation is done using optical orthogonal spreading codes and the results are compared with the channel allocation using the Genetic algorithm (GA) approach for the first time to the best of author's knowledge. The optical orthogonal code frequency allocation technique scheme is advantageous than the GA approach in terms of reduced optical bandwidth requirements and more number of channels with null FWM crosstalk points. The Entire simulation work in this paper is carried out using MATIAB7 and SIMULINK tool box.

7 illus, 1 table, 16 ref

017634   Ramamurthi B (Electrical Engineering Dep, TeNet Group, Indian Institute of Technology, Chennai-600 036, Email: bhaskar@tenet.res.in) : Broadband wireless technology for rural India. Indian J Radio Space Phys 2007, 36(3), 168-71.

Broadband services can be best provided in rural India using wireless technology. Given modest income levels, internet-based services are accessible to most of the rural populace only through a kiosk model of delivery. Such services call for a wireless system that can provide at least 256 kbps in a sustained manner, to each of around 200 villages within a radius of 20 km from an Internet POP (Post Office Protocol). The challenge, however, is to do this at a cost per connection of under US$ 250 for the wireless equipment, in order to make the kiosk a viable business. Emerging wide-area broadband wireless technologies such as those based on the IEEE 802.16 (WiMAX) standard, when mature, may meet these performance and cost requirements. If broadband services are to be provided today, and at an affordable cost, one has to look for innovative ways of adapting low-cost, high bit-rate, and high-capacity technologies meant for local networks. Two standards that are amenable to such adaptation are DECT and IEEE 802.11 (WiFi), and Broadband corDECT and WiFiRe systems are, respectively, examples thereof. The corDECT system has been proven in rural deployments and shown to provide a feasible solution.

017633   Ramachander S (TeNet Group, Indian Institute of Technology, Chennai-600 036) : Rural connectivity in India: The n-Logue example. Indian J Radio Space Phys 2007, 36(3), 188-91.

Aims to explain about the telecom boom in India and throws light on the technologies of today and tomorrow. It briefly discusses about, how technologies are now starting to be available to connect every village and also it details challenges faced by the technologies in rural areas. With these in mind a total innovative business model was required to deliver Internet services to rural areas. In order to meet this need a company called n-Logue was incubated to significantly enhance the quality of life of every rural Indian by setting up a network of wirelessly connected internet kiosks in villages throughout India. The challenges from technology point of view are many. The systems that provide connectivity need to be relatively inexpensive if they are to be commercially deployed, given the lower incomes in rural areas compared to urban areas. This paper concludes by saying that with the help of drastic developments in technology sector, providing connectivity in rural areas is entirely possible today.

017632   Rama Rao P V S (Physics Dep, Andhra University, Visakhapatnam 530 003, Email: palurirao@yahoo.com) : On the progress of four decades of beacon satellite studies in India - a brief review. Indian J Radio Space Phys 2007, 36(6), 474-88.

Forty years of progress of the radio beacon research of the ionosphere carried out in India using the signals from both orbiting as well as geostationary satellites by various researchers has been briefly reviewed. Several features in the typical equatorial and low latitude characteristics on the occurrence and morphological behaviour of the total electron content (TEC) and the ionospheric scintillations are presented. The need for the measurement of absolute TEC, its real time prediction as well as the prediction in the onset of scintillations, their amplitudes and durations, in the context of the possible application of these space weather phenomena in the satellite based communication and navigation systems, with particular reference to the effective implementation of the programmes such as GPS Aided Geo Augmented Navigation (GAGAN) are discussed.

017631   Prasad M V S N;Ratnamala K;Gupta M M;Sarkar S K (NO, National Physical Lab, Radio & Atmospheric Sciences Div, New Delhi-110, , Email: e-mail: mvprasad@mail.nplindia.ernet.in ) : Application of classical two-ray and other models for coverage predictions of rural mobile communications over various zones of India. Indian J Radio Space Phys 2007, 36(5), 423-29.

The development of various prediction tools requires the comparison of radio measurements with prediction methods. For a country like India where diverse terrain conditions exist, same prediction method might not hold good in all the regions. To identify the methods suitable to rural zones an attempt is made to compare the measured results with classical two-ray, Hata and ITM methods. Their efficacies have been evaluated in terms of statistical parameters like error distribution functions,etc.

017630   Paulraj A (Information Systems Laboratory (ISL), Stanford University, 272 David Packard Electrical Engineering Building 350 Serra Mall, Stanford, CA 94305-9510, USA) : IEEE 802.16e (Mobile-WiMAX) for rural deployment. Indian J Radio Space Phys 2007, 36(3), 178-81.

The IEEE 802.16e (or simply 16e) is an emerging global standard targeted for broadband services to mobile/nomadic users within urban areas with macro cellular type deployment. Other applications of 16e can be micro cell indoors and outdoors serving hotspots and enterprises. The 16e promises wideband operation with high spectral efficiency. Net throughputs up to net 70 mbps peak and 20 mbps average are possible in 10 MHz channels. The 16e standard for urban mobile applications is expected to be ratified in Sep. 2005. The WIMAX forum has approved two profiles wave 1 and 2. The former is entering Korean deployment in mid 2006. Wave 2 profiles address more advanced features will begin trials in late 2006. Clearly, 16e is a very flexible standard capable of multiple applications. Argues that the flexibility in 16e also makes it suitable for efficiently supporting rural applications also. Requirements for rural deployment and a possible rural profile for 16e are discussed. Also it is shown that it can be configured to offer attractive performance and cost advantages.

017629   Pant S R (Central Dep of Geology, Tribhuvan Univ, Kirtipur, Kathmandu, Nepal, Email: spant@wlink.com.np) : Application of geoelectrical methods in hydropower projects of Nepal. J Geophys 2007, 28(3-4), 121-36.

Until mid-90s conventional seismic refraction method was the only subsurface geophysical investigation in hydropower projects of Nepal. Usually proposed study areas He in the mountain and are inaccessible for vehicular transportation. Very high heterogeneity of surface material creates poor energy coupling for both source and receiver. Because of the high-energy content and easy transportability, explosives were the preferred source for the generation of seismic waves. Due to the rebel activities in the recent years, however, the government has tightened regulations on transporting and using explosives. This situation has forced the hydropower projects to search for alternative geophysical methods in place of seismic refraction. Electrical resistivity tomography (ERT) was selected as a possible replacement method. In the initial stage of the application of ERT, various electrode arrays and data acquisition approaches were evaluated for data quality and subsurface resolution. Experience in different projects reveals that the pole-dipole electrode arrangement with data levels at different electrode spacing is suitable for better resolution of the subsurface material. Other geoelectrical methods that used to study the subsurface are the self-potential (SP) and mise-a-masse methods. SP-method was used to localize the leakage and outflow area in the existing dam and mise-a-masse method was used to assess the groundwater flow velocity in the proposed dam area. The results of the investigation indicates that these methods can furnish most of the subsurface information needed for a hydropower project.

14 illus, 20 ref