005747   Jain M;Sharma G C;Chakrabarti S (Mathematics Dep, Institute of Basic Science, Khandari, Agra-282 002, Email: madhujain@sancharnet.in) : Cellular radio networks : A perspective. Everymans Sci 2008, 63(4), 225-9.

Wireless technology is the fastest growing segment of telecommunications. The evolution of the wireless technique has resulted in a large number of changes in the paradigm of the way we communicate. Technological advances and rapid development of the handled wireless terminals allow cellular subscriber to wander anywhere in the country by remaining connected to the public switch telephone network (PSTN) via the mobile phones. The focus of this article is to provide a detailed discussion on the performance issues related to the cellular radio systems. It also overviews the different channel assignment schemes and their comparison on the basis of the performance and flexibility. Moreover, innovations and the future directions of the cellular mobile technology have also been discussed.

3 illus, 6 ref

005746   Islam R;Praveena D;John J;Sumesh M A;Nagendra C L;Alex T K (Laboratory for Electro-Optics Systems, ISRO, Peenya 1st Stage, 1st Cross, Bangalore-560 058) : Development of micro fluxgate magnetic sensor for space application. J Spacecraft Technol 2008, 18(2), 19-25.

The characterization, screening and qualification of indigenously developed micro-fluxgate magnetic sensor on silicon wafer are reported in this paper. The sensing structure is rectangular-ring shaped electroplated permalloy as magnetic core and this is wound with electroplated copper as 3-dimensional (3D) excitation and sensing coils. The 3D coils, designed to carry a current about 500 mA in order to saturate 10 μm thick magnetic core was realized by a modified UV-LIGA [a German acronym for lithography (Lithographie), Electroplating (Galvanoformung), and Molding (Abformung)], process indigenously developed at LEOS. The detection scheme is based on second harmonic principle and the sensor is characterized using lock-in-amplifier. The fabricated sensor has dynamic range of ±60 μT, a noise of 500 nT, a sensitivity of 300V/T and an average power dissipation of 160mW for 400 mA peak excitation at 25kHz. The developed magnetic sensor chip has substantial weight reduction compared to the conventional one presently used onboard. The sensor chip as well as sensor chip along with detection electronics successfully undergone screening and qualification test as per stringent space qualification requirement and the sensor is delivered to MIS project.

8 illus, 1 table, 5 ref

005745   Helenprabha K;Natarahan A M (ECE Dep, Kongu Engineering College Perundurai, Erode, Email: Helenpradbha@yahoo.com) : Fetal electrocardiogram extraction from noisy environmental using negative error gradient algorithms. Int J appl mathl Analysis Applic 2007, 2(1-2), 37-46.

Fetal electrocardiogram (FECG) monitoring is a technique for obtaining important information about the condition of the fetus during pregnancy and labour. This technique is used for measuring electrical signals generated by the fetal heart as measured from multichannel potential recordings on the mother's body surface. Unfortunately, the desired fetal heart signals appear with undesirable disturbances. To extract FECG from the several contaminations, propose a new class of adaptive filter using negative error gradient algorithms. Each iteration the weight is updated depending upon the negative gradient error. The simulation results of the FECG data demonstrate the effectiveness of noise cancellation algorithm and as a result FECG can be calculated.

14 illus, 11 ref

005744   Desai M N;Talati J D;Yyas C V;Shah N K (Chemistry Dep, University School of Sciences, Gujarat Univ, Ahmedabad-380 009, Email: mndesai23@yahoo.com) : Some schiff bases as corrosion inhibitors for zine in sulphuric acid. Indian J chem Technol 2008, 15(3), 228-37.

The inhibition of corrosion of zinc in sulphuric acid by Schiff bases aniline-N-benzylidene(ANB), aniline-N-salicylidene(ANS), aniline-N-p-methoxybenzylidene(ANPMB), p-methoxybenzylidene-4,4'-dimorpholine(p-MBDM) and salicylidene-4-4'-dimorpholine(SDM) has been studied with respect to inhibitor concentration, exposure period, and temperature. More than 99% inhibition is achieved with 0.5% concentration of inhibitor except in case of ANB whose efficiency is found to decrease with time and rise in temperature. The activation energies in inhibited acid are higher than that in plain acid. For all the inhibitors, the heats of adsorption and free energies of adsorption are negative, while the entropies of adsorption are positive. The free energies are more negative in the case of inhibitors like ANS, SDM, ANPMB and p-MBDM. It appears that an efficient inhibitor is characterized by a relatively greater decrease in free energy of adsorption and less negative entropies of adsorption. Galvanostatic polarization data suggest that these are mixed type inhibitors with preferential action on local cathodes. Cathodic protection studies suggest that the protection is achieved at current densities much lower than that in plain acid. The conjoint effect of external cathodic current and the inhibitor is observed to be synergistic in most of the cases. The inhibitors appear to function through adsorption following Langmuir isotherm.

3 illus, 7 tables, 24 ref

005743   Bhuvaneswari R;Subramanian S;Thomas Bellarmine G (Electrical Engineering Dep, Faculty of Engineering and Technology, Annamalai Univ, Tamilnadu-608 002, Email: boonisridhar@rediffmail.com) : Differential evolution based design of three-phase induction motor. Int J appl mathl Analysis Applic 2007, 2(1-2), 23-36.

An efficient and reliable Differential Evolution (DE) based approach to Optimal Design of three-phase Induction Motor (ODIM) is proposed. The main contribution of this work regards the application of DE in the solution of induction motor optimization problem to search for optimal values of induction motor design parameters where classical techniques may fail to obtain optimal solutions or may be inefficient to implement. The proposed approach has been examined and tested on two sample motors with different objectives that reflect the motor's efficiency, active material cost, and performance under starting and full load conditions and the results have been compared to those that reported in the literature recently. The results are promising and show the effectiveness and robustness of the proposed approach.

6 illus, 4 tables, 23 ref

005742   Bhan R;Misra T (Space Applictions Centre, ISRO, Ahmedabad) : Novel collimation correction of active array antenna implemented in RISAT*. J Spacecraft Technol 2008, 18(2), 51-60.

Traditionally, collimation error estimation of an active array antenna is carried out from the Near-Field (NF) hologram where all the elements of the active array antenna are illuminated simultaneously. However, typical NF processing resolution is ~λ and typical element spacing in scan direction is less than ~0.7 λ. Consequently it becomes very difficult to resolve amplitude and phase errors, especially in the presence of sharp amplitude and phase discontinuities. Further, this method requires area scanning of antenna in near field to obtain hologram. Paper presents a novel method, where amplitude and gain response of individual rows are measured using a single scan. For this purpose, TR modules are switched one at a time. The correction coefficients, estimated with this method, are very accurate and free from aforementioned distortions because of wide impulse response of NF processor. Further, only a linear scan is sufficient to assess the correction factors with significant impact on the time required for such estimation.

21 illus

005741   Akila S;Krishna Kumar E (Flight Dynamics Div, Mission Development Grop, ISRO Satelite Center, Bangalore-560 017) : Onboard filter based compensation for a reduced order orbit model. J Spacecraft Technol 2008, 18(2), 1-18.

Estimating the orbital parameters of the user spacecraft using the Space borne Navigation data available onboard is the best solution to the problem of Autonomous Orbit Determination (OD) for Low Earth Orbit(LEO) or Medium Earth Orbit (MEO) satellites. The approach followed to realize this solution involves two steps. First step is to arrive at the simplest model which can account for the major contributions from the various acceleration components. This has significant advantages in terms of processing load for Onboard OD. The results of the first step, namely model study, was already published. The next step is to improve the accuracy of the onboard knowledge of the orbit by introducing a Kalman Filter(KF) Estimation Scheme to compensate for the uncertainties arising from the reduced order orbit model. The detailed analysis and results of the Estimation Scheme are presented in this paper. The proposed scheme is simple for implementation and has scope for closed-form-solution of intermediate steps. Additionally this provides performance improvement by one order (10 times) for the knowledge of spacecraft position. The improvement is accomplished by modeling the process noise as a stochastic process with exponentially correlated noise model. It is known that the knowledge of velocity components of GPS navigation solution is relatively poorer. The compensation procedure involving estimation of time-correlation-coefficients also leads to some more degradation of the velocity components. Therefore the proposed novel scheme in this paper additionally introduces an appropriate adaptive scheme to update the characteristics of measurement uncertainties. A proper combination of the previous measurement noise covariance with the current residues is incorporated to realize better accuracy in velocity estimates. Results of the detailed analysis carried out for the proposed realization of autonomous onboard OD using the dynamical recovery of the force components is demonstrated for the actual data of IRS-P6.

17 illus, 7 tables, 6 ref

005740   Ahmad N;Behara R;Shankar Narayan S;Sriranga T S;Samuel R (Structure Group, ISRO Satellite Center, Airport Road, Bangalore-560 017) : Simulation of spacecraft motion in separation test. J Spacecraft Technol 2008, 18(2), 42-50.

Paper presents a mathematical model of the spacecraft motion during the separation test on a low frequency suspension system that is designed and fabricated in order to simulate the free-fall condition of the spacecraft as it occurs in space during the spacecraft separation from the launch vehicle. The suspension system consisted of elastic bungee cords to hold the spacecraft in course of the separation process during the test. The model, developed here to predict the parameters of the rigid-body separation dynamics, incorporates the effect of ejection springs and nonlinear behavior of the bungee cords. The Lagrange method was used to drive the equations of motion and was solved using forth order Runge-Kutta method. Separation tests were carried on structural model of spacecraft by releasing the clamp-band. The displacement of the spacecraft was measured by a high accuracy Laser Tracker. The predicted response of the spacecraft matches closely with the test data.

8 illus, 3 tables, 4 ref

004793   Yadav S K;Katta D;Kale S R (NO, , Reliance Industries Limited, Vadodara, Email: shravan.bits407@gmail.com) : New approach to design an acid absorption crystallizer to minimize steam consumption. J Coop Univ Res Ind Enterpr 2009, 1(4), 41-8.

Steam consumption is a cause of great worry for the people concerned with process industry. Application of acid absorption crystallizer (AAC) in the area of crystallization is a new but promising technique for performance prediction. It is considered to be a powerful technique in overcoming the limitation of conventional crystallization process. In AAC the hygroscopic property of acid is used to reduce the steam consumption and improve the economy of the auxiliary process plant. This paper nimncs on the designing of acid absorption crystallization (AAC) process for the production of Na₂SO₄ crystals from spin bath solution.

1 illus, 5 ref

004792   Venkatachalam D;Rama Mohan Rao A (NO, Birla institute of Technology and Science, Pilani-333 031, Email: dhanyavenkatachalam@gmail.com) : Non-destructive damage detection technique for civil infrastructure. J Coop Univ Res Ind Enterpr 2009, 1(4), 5-11.

Structural damage detection and integrity assessment is one of the fundamental objectives of structural health monitoring. In such applications, it is highly desirable to detect the earliest occurrence of damage in a structure by examining changes in its measured responses. Structural vibration responses such as accelerations are the most commonly used measurements partly due to the hypothesis that damage changes the physical properties of a structure, which in turn will cause changes to the vibration characteristics of the structure. This paper presents a technique for detecting and locating damage in structures by applying concepts derived from the theory of proper orthogonal decomposition. A simply supported bridge girder and a ten storey framed structure are considered as numerical examples in this paper to demonstrate the effectiveness of the proposed damage detection technique.

9 illus, 10 ref

004791   Selvanambi P;Thirumurthy A M;Palanivel P M (NO, Highway Research Station, Chennai, Tamilnadu) : Comparative studies on the properties of sand asphalt base course design and slag-dust base course design. Indian Highw 2008, 36(5), 9-14.

Design properties of Sand Asphalt Base course (SAB) and granulated copper Slag Dust Base course (SDB) are analyzed. The Marshall method of mix design is followed for both the base course design. The open graded aggregate system has been followed for the designs. The mix design properties like stability, flow, binder content are compared with close graded mix. The air voids, percentage voids in mineral aggregate, percentage voids filled with bitumen are analysed as a factor for consideration during the design of open graded mix. It is observed that the sand asphalt base course design requires more binder than that of copper slagªdust base design. The comparison of these two base course designs indicates that the copper slag dust base course design yields better Marshall properties than that of sand asphalt base course design. Cost comparison of these two base designs indicate that the copper slag base is economical than sand asphalt base course.

10 tables, 11 ref

004790   Sarsam S I (NO, Civil Engineering Dep, Iraq, Email: saadisasarsam3@yahoo.com) : Evaluating and testing rheological and physical properties of mastic asphalt. Indian Highw 2008, 36(5), 23-8.

Primary objective of this work is to prepare, test, and evaluate mastic asphalt specimens with different ingredients and study the effect of such ingredients on rheological and physical properties, and evaluate the suitability of the existing testing procedures, and possibility of introducing other testing equipments and methods. A total of eleven different mastic asphalt specimens have been prepared in the laboratory by mixing asphalt cement with lime, rubber, sulphur, and a combination of them and adding used lubrication oil or recycling agent at elevated temperature. The specimens were subjected to penetration, ductility, softening point, flow, elastic strain recovery, and cold bond tests. The effect of each ingredient of the mastic asphalt on physical, rheological, and elastic properties have been studied and discussed. It was concluded that it is important that the Mastic Asphalt should be subjected to a combination of testing procedures as those conducted in this work to evaluate the suitability of the mastic for joint sealing, paving or roofing. Mastic asphalt prepared from (Asphalt cement, 10% rubber and 20% lime), or from (Asphalt cement, 5% sulphur, 10% rubber and 20% lime) and from (Asphalt cement, 20% lime and 2% recycling agent) satisfies the specification requirements.

8 tables, 21 ref

004789   Rikh V N (FIET, , London) : Bundle conductors for EHV lines; economic selection may leave usefful margin in corona performance. Wat Energy int 2007, 64(4), 82-6.

The selection of Bundle configuration is commonly based on technoªeconomic optimization while ensuring a satisfactory - though not optimum- corona/RI performance. This leaves a margin for improving their corona/RI performance, while passing through any corona/RI sensitive areas along the line route, just by changing their intra-group (lG) spacing. The presently used 45 cm IG spacing on Twin-Moose Bundle conductor for Indian 400 kV lines is based on techno-economic choice but not corona optimal and could be reduced to 16-17 cm to achieve corona optimality though the improvement in corona/RI performance of the Bundle through this reduction is only around 3.5%. This may be too small for practical use but does suggest a smaller IG spacing. There is therefore an urgent need to review the present Bundle configuration is in the context of completely changed techno-economic scenario.

3 illus, 1 table, 3 ref

004788   Ramamurti V (NO, , Old No.18; New No. 10, Second Main Road, Nehru Nagar, Chennai-600 020) : Vibration problems in industry - Indian scenario. Proc Indian Natn Sci Acad 2008, 74(1), 39-45.

15 illus, 3 tables, 2 ref

004787   Pankaj Kumar;Vyas H (NO, , ) : Use of software tools to evaluate and assess the performance of transmission lines. Wat Energy int 2007, 64(4), 65-72.

Aims estimate failure rates and restoration time for overhead lines as functions of operating voltage, circuit length, to genera it: a data base for analysis of three phase faults, pollution related failures etc. This analysis becomes all the more necessary as certain lines of POWERGRID are terminating at substations owned by other utilities and outages at such terminals cause disruption of power thus decreasing availability of the system.

6 illus, 8 tables, 2 ref

004786   Nath A K (Mechanical Engineering Dep, Indian Institute of Technology, Kharagpur, Kharagpur-721 302, Email: aknath@mech.iitkgp.ernet.in) : Indigenously developed high power CO₂ lasers in material processing applications. J Coop Univ Res Ind Enterpr 2008, 1(3), 26-32.

Lasers have made immense impact in the area of manufacturing. They are being used in different industries for cutting, welding, surface hardening, surface alloying and cladding, surface texturing, metal forming, and rapid prototyping and manufacturing. Considering that indigenous development of high power lasers could help in adopting this advanced technology in the country a comprehensive programme on the development of industrial lasers and laser material processing applications was initiated at the Centre for Advanced Technology, Indore. High power continuous wave CO₂ lasers of I powers up to 20 kW and a pulsed TEA CO₂ laser of 500 W average power were successfully developed and several laser material processing applications were established using these lasers. These include laser cutting of metal and nonmetals, welding of nuclear and auto components, laser re-melting, fabrication of functionally graded parts and laser rapid manufacturing of samples with different metal powders. An overview of these developments is presented.

12 illus, 10 ref

004785   Nadaf M D;Mumtaz J (NO, BBMP, Bangalore, Karnataka) : Procedure and guidelines for obtaining prior permissions for repairs, maintenance and widening of road in forest land. Indian Highw 2008, 36(5), 15-22.

2 illus, 1 table, 11 ref

004784   Mathew B S;Reshmy D S;Saac K P (NO, College of Engineering, Trivandrum) : Performance modeling of rural road pavements using artificial neural network. Indian Highw 2008, 36(1), 31-9.

The integral development of India is highly influenced by the development of rural roads. Government of India has been investing huge amounts on rural connectivity. Flexible pavements form considerable part of the rural roads because of the low construction cost involved. But the flexible pavement deteriorates at faster rate, shortening the service life. Periodic upkeep and maintenance are needed for the preservation of these roads. As the funds available are limited in a developing country, scientific pavement management tools are necessary. Pavement Maintenance and Management System (PMMS) make use of the deterioration models to predict pavement condition at a future date, based on which the maintenance strategy is formulated. Currently, mechanistic-empirical and purely empirical models are popular tools for forecasting pavement distress. However, with a large data dimension, it is difficult to select appropriate mathematical function forms for the above models. This study is an effort to model the performance of rural roads using Artificial Neural Networks (ANN). In the present study eight rural roads in Thiruvananthapuram district were selected. The length of the study section was fixed as 0.5 km. Each study stretch was further divided into 50 sections of 10 m each. Detailed data collected included pavement age, pavement thickness, subgrade strength and severity of different distresses. The main distresses observed on these roads were ravelling, pothole and edge failure. The models were developed for construction quality and drainage in neural network to use in the deterioration models. Deterioration models were developed for ravelling initiation and progression, pothole progression, roughness progression and edge failure using neural network and regression techniques. The variations in pavement condition index values for all these roads were determined with age. The ANN models were compared with the available regression models. The ANN models were found to be more suitable to the rural roads than the conventional empirical statistical models.

1 illus, 7 tables, 4 ref

004783   Mahswari R (Associated Software Analyst, Bally Technology, Chennai, Email: maheswari_20@hotmail.com) : RTOS based machine controller through speech using ESTREL. J Coop Univ Res Ind Enterpr 2008, 1(3), 64-71.

Embedded system architecture is developed in a mobile-like handset device for controlling machineries in Industries through wireless mode of communication. Speech recognition is the ability of machines to respond to spoken commands. This mechanism is activated in two ways viz. speech and manually The speech implementation is performed when speech input is given to the device. A software program is developed for recognizing the commands. It performs according to the conditions specified in the code and corresponding machinery actions are controlled. The manual implementation is executed when the user presses on the button, which is designed to control all necessary actions in the Machine. This method of automating the machines in the Industry serves as a communication & controlling aid to the differently-able people working in the Industries. This paper deals with the design of the RTOS based Machine Controller through Speech using ESTREL.

2 illus, 10 ref

004782   Leena A;Sharma S C (Electronics & Computer Discipline, IIT Roorkee, Saharanpur Campus, Email: leenadpt@iitr.ernet.in ) : Design and fabrication of GSM based robot control. J Coop Univ Res Ind Enterpr 2009, 1(4), 12-16.

Robotics has revolutionized the field of computer science 'As Knowledge is power'. Its application can be beneficial or detrimental in the entire field like Science, Engineering, Communication, Control, Wireless etc. This paper briefly discusses the Design, Fabrication, implementation and operation of electrical and electronics systems hardware involved to control any robot with the help of the satellite communication. Designs have used coded multi-frequency to control the robot from any other mobile phone. The circuits used are acoustically coupled to the telephone instrument to make independent on telephone department and to save cost of call. The switching is performed by coded telephone ring signal. The paper deals with design and experimental of GSM based robotic coded telephone ring signal, which can be useful for the people who are working in research laboratory, industry & education in the field of Robotics Control for vehicle, fountain sprayer and spying purpose in the enemy area.

4 illus, 4 ref

004781   Krishna Murthy M C;Vijayakumar P (NO, B.M.S. Evening College of Engineering, Bangalore-019, Email: mck_bms@yahoo.co.in) : Effect of thermal cycling on vibration damping in SiC/Al composites. J Coop Univ Res Ind Enterpr 2009, 1(4), 56-61.

The investigation on dynamic elastic modulus and vibrational damping has been carried out at room temperature for Al6061 and Al/SiC composites. The specimens were subjected to thermal cycles up to 500°C. The piezoelectric ultrasonic composite oscillator technique (PUCOT) was used to determine the Young's modulus and damping. Archimedes' method was used to find the density of the specimens. The experimental results showed that thermal cycling of the composites below recrystallization had no distinguishable effect on the density, dynamic Young's modulus; however, an increase in damping of 32% was observed. After thermal cycling the density decreased by about 1.3%, the Young's modulus decreased by 12 %, the flexural modulus decreased by 18% and the damping increased by 63%. This enhanced properties with thermal cycling temperature were analyzed in terms of microstructural degradation due to thermal effects on the matrix, paniculate and interfaces.

5 illus, 1 table, 11 ref

004780   Jagadeeswar Reddy G;Jaya Chandra Prasad T; GiriPrasad M N (ECE Dep, SVIST, Kadapa-516 003, Email: jagsuni@yahoo.com ) : Image denoising by curvelets. J Coop Univ Res Ind Enterpr 2009, 1(4), 81-91.

The problem of recovering an image from noisy data arises in many different areas of scientific investigation and medical imaging. The traditional methods behave poorly when the object to recover has edges. A new system of representation, namely, the curvelets, was developed over several years in an attempt to break an inherent limit plaguing wavelet denoising of images. The author (a) and standard images were denoised using both wavelet and curvelet transforms and results are presented in this paper. It has been found that the curvelet reconstructions exhibit higher perceptual quality than wavelet-based reconstructions, offering visually sharper images and, in particular, higher quality recovery of edges and of faint linear and curvilinear features. Existing theory for curvelet transform suggests that this new approach can outperform wavelet methods in certain image reconstruction problems, such as image denoising and compression.

4 illus, 2 tables, 11 ref

004779   Hari Prasad K S;Abdul Hussain I A;Jitendra Singh (Civil Engng Dep, I.I.T., Roorkee) : Finite element numerical model for unsaturated flow in layered soils. Wat Energy int 2007, 64(4), 40-6.

A Galerkin finite element numerical model is developed to analyse moisture movement in layered soils. The model basically solves the Richards equation governing moisture flow through unsaturated zone using the constitutive relationships proposed by Van Genuchten. The model is applied to analyse the flow behaviour in a layered soil consisting of sand and clay during gravity drainage and infiltration. It has been observed that the movement of water in layered soils is a complex process which is influenced by the relative thickness and position of individual layers.

8 illus, 13 ref

004778   Gajanan V S (NO, , BITS, Pilani-Goa Campus, Zuri Nagar-403 726, Email: shraddhagv001@yahoo.co.in) : Trajectory tracking for AGV (automated guided vehicle). J Coop Univ Res Ind Enterpr 2008, 1(3), 51-7.

Automated guided vehicles (AGVs) help to reduce costs of manufacturing and increase efficiency in a manufacturing system. Routing and scheduling of these mobile robots is done to ensure that they follow the pre-defined path and overcome errors due to hardware limitations. The pure-pursuit algorithm uses the analogy of human driving i.e. chasing a moving goal point. PID (Proportional-Integral-Differential) algorithm is used for correcting the error in the vehicle's heading. Both of these trajectory tracking algorithms take constant feedback and compute the variable, controlling the motion, continuously. It is implemented using ARIA-software, written in C++ language. The program was run successfully on SMART-NAV (Smart-Navigator) - the mobile robot developed by DRHR (Department of Remote Handling and Robotics) at BARC, Mumbai.

7 illus, 9 ref

004777   Ashokan A;Valmiki R K (NO, Institute of Technology and Science, Pilani-Goa Campus, Email: anitha86.bits@gmail.com ) : Statistics metering logic to monitor AMBA-AHB bus activities. J Coop Univ Res Ind Enterpr 2008, 1(3), 72-82.

The primary concerns for any system design are: efficient transfer of data between devices, effective usage of bus, transaction time, and reducing overall cost. An important feature of the AHB bus is pipelining which is being exploited to meet these requirements. Pipelining allows execution of a second instruction before the first has been completed, i.e., several instructions are in the pipeline simultaneously, each at a different processing stage. It is necessary to determine the performance of the bus to make sure that the system behavior satisfies the design specifications. For this purpose, a bus monitor is developed. It tracks the activities of the bus at the transaction level and a wide range of statistics is logged in. The statistics is then analyzed and the system design is modified to suit the needs. The monitor is flexible and can be incorporated in to any system design that uses AHB bus for data transfers. This work has been carried out as a part of university industry collaboration between BITS Pilani and SiRF Technology, Bangalore.

3 tables

004776   Arularasan R;Velraj R (Mechanical Engineering Dep, SSN College of Engineering, Tamil Nadu-603 110, Email: arularasanr@ssn.edu.in) : Performance improvement and parametric optimisation of a parallel plate heat sink. J Coop Univ Res Ind Enterpr 2009, 1(4), 49-55.

Heat dissipation becomes a significant issue in efficiency promotion and stable operation of air cooled electronics components and assemblies. The use of finned heat sinks increases the effective surface area for convective heat transfer thereby reducing the operating temperatures of electronic devices. The objective of a heat sink is to achieve maximum heat dissipation, while restricting the consumption of valuable resources such as mass, fan power, pressure drop and space. Optimal design of the heat sink is a significant task. Therefore preliminary studies on the heat transfer characteristics of a parallel plate heat sink have been carried out in association with Society for Applied Microwave Electronic and Research Center for Electromagnetics - SAMEER-CEM - Chennai- 600 113. In this research work, the geometric parameters considered are number of fins, fin length, fin height and base height. Studies have been performed through design of experiments (DOE) methodology in conjunction with simulation results. The simulation is carried out with a commercial package provided by Fluent Inc. The results are analyzed using analysis of variance and response graphs. In this study, the geometric parameters namely number of fins, fin height and base height are found to be significant at low (20 Nos), high (30 mm) and high level (7.5 mm) respectively for an efficient heat sink design.

3 illus, 3 tables, 7 ref

004775   Anjaneyulu M V L R;Nagaraj B N (Civil Engineering Dep, NIT, Calicut-673 601, Email: mvlr@nitc.ac.in) : Modelling of acceleration and deceleration characteristics of vehicles. Indian Highw 2008, 36(5), 29-39.

Models of acceleration and deceleration characteristics of vehicles are essential for many traffic engineering applications. Many researchers have represented the acceleration characteristics by means of constant values or simple equations, but these are unrealistic. Zero jerk acceleration models, which are considered to be realistic, seldom reflect the driver behaviour. Presents the development of acceleration and deceleration models that reflect the driver behaviour for various classes of vehicles in mixed traffic. The data required for the study was collected using photographic method. Regression models of average acceleration/deceleration in terms of speed revealed that average acceleration decreases with increase in speed, where as, the deceleration increases with increase in speed. The component of the models that represent the driver behaviour was found to follow Normal distribution.

4 illus, 7 tables, 8 ref

003725   Yazici S;Sezer G I (Civil Engineering Dep, Ege Univ, 35100 Izmir, Turkey, Email: semsiyazici@gmail.com) : Effect of elevated temperatures and time on compressive and tensile properties of concretes. Indian J Engng Mater Sci 2008, 15(1), 23-8.

Effects of temperature level and time on the mechanical behaviour of concrete have been investigated. The concrete mixtures are produced using two different water/cement (w/c) ratios: 0.4, and 0.6. 288 cube (100 x 100 x 100 mm) specimens are prepared from these concrete mixtures and cured at 28 days. After standard curing period, specimens are dried in a furnace at 105°C for 4 h. Then the specimens are kept in loboratory for 1 day before exposing to 300, 600 and 900°C for 1, 3, and 5 h. Then compressive strength and split tensile strength are determined. It is concluded that, compressive strength and split tensile strength of the specimens are reduced after the high temperature exposure. Compressive strength losses of tested concretes are reduced with increasing w/c ratio. Remarkable effect is occurred in first 3 h in terms of strength losses.

5 illus, 2 tables, 14 ref

003724   Vedalakshmi R;Sundara Raj A;Palaniswamy N (Corrosion Protection Div, Central Electrochemical Research Institute, Karaikudi-630 006, Email: corrveda@yahoo.co.in) : Identification of various chemical phenomena in concrete using thermal analysis. Indian J chem Technol 2008, 15(4), 388-96.

Chemical changes that occur in concrete at the microstructure level due to environmental effects are normally identified by SEM, XRD, thermal analysis and by chemical analysis. In the investigation, the chemical compounds formed in various chemical reactions are quantified using thermal analysis. The concrete having characteristic compressive strength of 20 MPa was subjected to undergo various chemical reactions for a specified period. Three types of cements were used for casting the concrete specimens. The thermal analyses (DTA and TG) were carried out on powdered concrete samples passing through 75 μm sieve drawn from the concrete specimens which were subjected to various chemical phenomenon. Chemical compounds such as Ca(OH)₂, gypsum, ettringite, calcium chloroaluminate are estimated quantitatively. The type of fly ash blended with cement and complex amine salt in Migrating Corrosion Inhibitor (MCI) treated concrete are also identified. Each chemical compound is identified by a distinct endotherm present in the DTA (Differential Thermal Analysis) plot and quantitative estimation has been done using the TG (Thermo-gravimetric) curve.

9 illus, 9 tables, 39 ref

003723   Vedalakshmi R;Rajagopal K;Palanisamy N (Corrosion Protection Div, Central Electrochemical Research Institute, Karaikudi-630 006, Email: corrveda@yahoo.co.in) : Enhanced corrosion resistance of rebar embedded in fly ash added concrete: role of "k" factor. Indian J chem Technol 2008, 15(4), 375-82.

In India, the abundant availability of fly ash necessitates the increase in the addition of fly ash in pozzolana cement from 25 to 35%. Higher replacement level of fly ash reduced the development of early age strength of concrete. By adopting the cement efficiency factor (k) when designing the fly ash added concrete, either equal or more compressive strength has been attained. In the present study, by adopting this factor, the concretes having strength of 20 and 35 MPa were designed at 40% replacement of fly ash. The enhanced corrosion resistance of rebar was evaluated by conducting chloride migration test, potential-time studies and 90 days chloride ponding test. Results were compared with Ordinary Portland cement (OPC) and Fly ash added concrete (FAC) without k factor. The studies reveal that the diffusion co-efficient of chloride is less in FAC- with k than that of OPC and FAC without k concretes. In 1% chloride contaminated concrete, the rebar in FAC- with k shows more passive potential than the other two concretes. Under 90 days chloride ponding test, the corrosion resistance of rebar in FAC is 3-7 times more than that of the rebar in OPC concrete. The reduced chloride ion penetration increased the corrosion resistance of rebar. The 40% replacement of fly ash reduced the alkalinity of FAC-without k whereas the OH ions concentration increases in FAC-with-k and maintained the passivity of rebar in presence of chloride. Hence in addition to early strength development, the enhanced corrosion resistance of rebar in FAC- with k is mainly because of reduced chloride ions penetration and increased OH" ions concentration.

6 illus, 8 tables, 30 ref

003722   Umoren S A;Ebenso E E (Chemistry Dep, Faculty of Science, Uyo Univ, Uyo, Nigeria, Email: saviourumoren@yahoo.com ) : Blends of polyvinyl pyrrolidone and polyacrylamide as corrosion inhibitors for aluminium in acidic medium. Indian J chem Technol 2008, 15(4), 355-63.

The corrosion and inhibition behaviour of aluminium in hydrochloric acid (HC1) in the absence and presence of polyvinyl pyrrolidone (PVP), Polyacrylamide (PA) and their blends was studied in the temperature range of 30 - 60°C using weight loss, hydrogen evolution and thermometric techniques. The inhibition efficiency (%I) increased with increase in inhibitors concentration. Increased in temperature led to increase in corrosion rate but decreased the inhibition efficiency PVP was found to have the higher inhibition efficiency than PA which may suggest that the differences in their molecular structures play a significant role in the adsorption and hence inhibition process. Inhibition efficiency was enhanced on blending the two polymers; the optimum inhibition efficiency was obtained at 3:1, blending ratio for PVP: PA. The inhibitors (PVP and PA) obey Freundlich, Temkin and Flory-Huggins adsorption isotherms at all the temperatures. Results obtained from the kinetic and thermodynamic parameters indicate spontaneous adsorption of the inhibitors unto aluminium surface following physical adsorption mechanism.

10 illus, 4 tables, 38 ref

003721   Tigdemir M (Civil Engineering Dep, Suleyman Demirel Univ, Isparta, Turkey, Email: tigdemir@mmf.sdu.edu.tr) : Dynamic permanent deformation testing of asphalt mixes and deformation waveform analysis. Indian J Engng Mater Sci 2008, 15(1), 29-35.

In study, different specimens of hot mix asphalt (HMA) have been constructed in the laboratory and tested under repeated loading; first permanent deformation and later fatigue tests using Suleyman Demirel University Asphalt Tester equipment (SDU-Asphalt Tester). This study reports evaluation of available information about relationship between permanent deformation and fatigue cracking. Analysis of data shows that the fatigue life of the pavement may be modelled in terms of data obtained from repeated loading axial permanent deformation test results. Based on the analysis of the estimation model for fatigue life from permanent deformation testing, it is concluded that for the evaluation of HMA in fatigue characterization, repeated load axial test for permanent testing can be used in a very satisfactory manner. To be able to model the fatigue lives, in addition to conventional fatigue model parameters new parameters from repeated load permanent deformation test are taken into consideration. Hence, only by examining the permanent deformation tests, it may be possible to predict the fatigue lives of the specimens without carrying out time-consuming fatigue tests.

6 illus, 5 tables, 15 ref

003720   Suman Lata;Chaudharu R S (Chemistry Dep, Hindu Girls College, Sonepat-131 001, Email: jakhar.suman@rediffmail.com) : Some triphosphates as corrosion inhibitors for mild steel in 3% NaCl solution. Indian J chem Technol 2008, 15(4), 364-74.

Inhibition of mild steel corrosion in 3% sodium chloride solution by sodium tripolyphosphate (STPP), sodium hexametaphosphate (SHMP) and adenosine triphosphate (ATP) in presence of 200 ppm zinc acetate has been investigated using weight loss, electrochemical polarisation and scanning electron microscopy techniques. Various corrosion parameters such as Tafel slopes, corrosion current density, heat of adsorption and activation energy value have been calculated to understand the inhibition mechanism. Inhibition efficiency increased with increase in concentration for STPP and SHMP whereas it decreased for ATP. However, inhibition efficiency decreased for all the three phosphates with increase in temperature. All the three phosphates acted as mixed inhibitors though anodic reactions are suppressed more in comparison to the cathodic reactions. STPP acted through chemisorption whereas SHMP and ATP are physically adsorbed over the surface of mild steel.

6 illus, 5 tables, 20 ref

003719   Srivastava A K;Xu C L;Wei B Q;Kishore R;Sood K N (Electron Microscope Section, Materials Characterization Div, National Physical Laboratory, Dr K S Krishnan Road, New Delhi-110 012, Email: aks@nplindia.ernet.in) : Microstructural features and mechanical properties of carbon nanotubes reinforced aluminum-based metal matrix composites. Indian J Engng Mater Sci 2008, 15(3), 247-55.

The composites of aluminum-carbon nanotubes, produced using catalytic chemical vapour deposition method, are prepared with initial composition of aluminum homogeneously mixed with I, 2, 4 and 10wt% nanotubes and subsequently hot-pressed. TEMs and a STEM have been used to study the as prepared carbon nanotubes and their distribution in aluminum matrix after reinforcement. A set of preliminary observations delineated that the yield of as produced nanotubes in carbonaceous is very high with an average diameter of about 45 nm and with straight and spiral shapes. In composites, these tubes have been seen uniformly distributed in aluminum matrix without any significant dimensional alteration. An enormous increase in microhardness of aluminum - 10wt% carbon nanotubes composites in contrast to pure aluminum has been a remarkable study. Some of the important microscopic details, electrical measurements and mechanical properties in the nanotubes and their composites have been elucidated and discussed.

9 illus, 1 table, 22 ref

003718   Srinivasan C (Materials Sciences, Maduria Kamaraj University, Madurai, Email: ceesri@yahoo.com) : Carbon nanotubbes in cancer therepy. Curr Sci 2008, 94(3), 300-1.

1 illus, 9 ref,

003717   Srinivasa Reddy D;Prasad C S R K (Civil Engineering Dep, National Institute of Technology, Warangal, Andhra Pradesh) : Design of signal incorporating Nitw saturation flow curves. Indian Highw 2008, 36(4), 63-70.

An attempt to modify Webster method of signal design for mixed traffic scenario with high percentage of two and three wheelers vehicular traffic, it was followed by evaluation and design of an existing signal at an intersection in a medium city, Warangal (Andhra Pradesh) for the measured turning movements and vehicular delays. For this purpose, field surveys such as physical inventory, volume count with turning movements, and delay studies have been conducted at the selected intersection. Saturation flow curves developed by NIT Warangal for mixed traffic conditions have been incorporated in the analysis. The Webster method using Webster saturation flow equation failed to arrive at optimum cycle length, but Webster method using NITW saturation flow concept produced optimum cycle length with minimum intersection control delay.

5 illus, 2 tables, 15 ref

003716   Sinha V K;Varshney S (Indian Roads Congress, , New Delhi) : Planning for aesthetics inn the elements of roads. Indian Highw 2008, 36(4), 51-6.

Just as there is a need for efficient design of the road infrastructure, there is a need for aesthetic design of the roads, along with the knowledge of placing decorative elements on the roads which are advantageous from safety point of view also. This does not mean delimiting creativity but it does mean helping planners, designers and engineers, in taking responsibilities. An aesthetic positive road traffic environment would be safer than any other environment. Understanding the role of aesthetics in good design will help civil engineers understand their place in society. Aesthetics must be integrated into the civil engineering curriculum. With even the smallest knowledge of what aesthetics is, and how it affects people, engineers can make better aesthetic decisions in the future. Perhaps then, with more attention to visual stimulation and human emotions in design, we will be able to revitalize our cities and recapture the spiritual aura that once made cities the place to be.

7 illus, 8 ref

003715   Singla B R;Marwaha S;Marwaha A (Electrical Engineering, Guru Teg Bahadar Khalsa Institute of Engineering and Technology, Chhapianwali, Malout, Muktasar, Punjab) : Design and simulation of fuzzy, neuro fuzzy based optimizer and comparative analysis of unit commitment problem. J Instn Engrs-Pt EL 2007, 88(Sept), 30-4.

Describes the application of fuzzy logic concept to unit commitment problem. The main objective of unit commitment is to minimize the total production cost over the study period and to satisfy the constraints imposed on the system, such as, power generation-load balance, spinning reserve, operating constraints minimum up time and minimum down time, etc. Several conventional methods are available to solve the unit commitment problem, but all these methods need the exact mathematical model of the system and there may be a chance of getting stuck at the local optimum. In this paper, fuzzy logic approach is described which achieves a logical and feasible economic cost of operation of power system without the need of exact mathematical formulation. Efficient methods of production can help reduce this cost. DP method is combined with fuzzy logic to obtain the production cost of thermal power plant. The system demand, the reserve requirements and the operational cost will serve as fuzzy quantities. Two fuzzy logic methods have been employed to combine with DP method. These methods are fuzzy logic approach and fuzzy neural approach. The results obtained from the fuzzy logic approach (FLA) are compared with the solution obtained from fuzzy neural approach. From the comparison, it is proved that the fuzzy neural approach is a powerful tool for solving such highly non-linear problems.

2 illus, 5 tables, 14 ref

003714   Singh B;Singh B P;Dwivedi S (Electrical Engineering Dep, Indian Institute of Technology, Hauz Khas, New Delhi-110 016) : DSP based implementation of direct torque control scheme for permanent magnet synchronous motor drive. J Instn Engrs-Pt EL 2007, 88(Sept), 35-44.

Deals with an analysis and hardware implementation of a Direct Torque Control (DTC) scheme for Permanent Magnet Synchronous Motor (PMSM) drive using a motion control digital signal processor (DSP). The DTC based PMSM drive system is implemented using minimum number of hardware components. The developed PMSM drive system consists of power circuit, control hardware and software. Power circuit consists of insulated gate bipolar transistor (IGBT) based voltage source inverter (VSI) and gate driver circuit. Hardware of control circuit consists of power supplies, voltage and current sensors and interfacing circuits. The reference speed, rotor speed estimation from sensed position signals, speed controller, torque, flux and sector estimator, optimum voltage vector selection table for gating pulse generation of direct torque controlled VSI are implemented in assembly language of DSP.ADMC401. The simulation model of the drive system is developed in MATLAB environment with simulink and PSB toolboxes to analyze the performance of the proposed drive system, The performance of the PMSM drive is studied for starting, steady-state condition, speed reversal and load perturbation.

8 illus, 1 table, 10 ref

003713   Singh B J;Aggarwal K K;Kumar S (Electronics and Communication Engineering, National institute of Technology, Kurushetra-136 119) : Characterization of the propagation environment by field measurements. J Instn Engrs-Pt ET 2007, 88(July), 22-5.

The field measurements of signal strength taken at the frequency of 871.26 MHz in a vehicular environment are presented and analyzed. The received signal levels from the base station were monitored from inside a van moving at the speed of about 30 km/h. Total coverage area considered for the measurement campaign consisted of a mixture of different propagation environments. Based on the experimental data obtained, path loss exponent and standard deviation of signal strength variability are derived. It is shown that the values of these parameters vary from region to region in the coverage area. The results indicate that different empirical models for mean signal strength should be used in different regions of the coverage area for cellular network planning.

6 illus, 1 table, 15 ref

003712   Singh B (Physics Dep, R H Government Post Graduate College, Uttarakhand-244 713) : Radiations from three different types of microstrip array antennas through lossless warm plasma. J Instn Engrs-Pt ET 2007, 88(July), 53-8.

In this paper the radiation performance of four elements linear, planar and circular array antennas composed of four identical microstrip circular patches have been presented. Expressions for electromagnetic and electroacoustic modes are obtained using well established hydrodynamic theory and pattern multiplication approach. The results in free space medium are computed and plotted taking plasma parameter as unity. It is observed that radiation characteristics of array antennas are altered significantly under the effect of plasma. The analysis is performed both in plasma and free space media, as these antennas find ample use in space communication.

6 illus, 1 table, 11 ref

003711   Shukla A K;Prem Kumar T (NO, Central Electrochemical Research Institute, Karaikudi-630 006, Email: shulka@sscu.iisu.ernet.in) : Materials for next-generation lithium batteries. Curr Sci 2008, 94(3), 314-31.

Likely developments awaiting the science and technology of next-generation lithium batteries form the focus of this article. New anode materials based on nano-structured carbpns and lithium-alloying metals, novel eco-friendly cathode materials, safe and non-flammable aprotic electrolytes, and polymer electrolytes are discussed. Possible scenarios for improvements in existing or presumed battery active materials are suggested. Advances in the science and technology of lithium batteries are previewed with a prognosis of challenges and opportunities in the development of marketable materials and products.

8 illus, 104 ref

003710   Shibukumar K S;Leslie R;Girija K (Airports Authority of India, , Trivandrum) : Locating damages in cable stayed bridges using flexibility index method. J Instn Engrs-Pt CI 2008, 88(Feb), 37-40.

Structural health monitoring of bridges involves measurement of dynamic properties to assess its structural integrity At the time of an anticipated damage, it is essential to detect and locate damage, if any Characterisation of modal parameters, namely, natural frequencies and mode shapes, is the most promising route to detection of damage, which is fast, reliable and economical. In this study, the flexibility index method, which involves comparison of the modal characteristics of the damaged and undamaged structure, is applied on the finite element model of a cable stayed bridge.

7 illus, 4 ref

003709   Seshadri Sekhar T;Srinivasa Rao P (NO, Vijay Rural Engineering College, Nizamabad-503 003) : Strength properties of glass fibre self-compacted concrete. J Instn Engrs-Pt CI 2008, 88(Feb), 61-5.

The present day world is witnessing the construction of very challenging and difficult civil engineering structures. Quite often, concrete being the most important and widely used material is called upon to possess very high strength and sufficient workability properties. Efforts are being-made in the field of concrete technology to develop such concretes with special characteristics. Researchers all over the world are attempting to develop high performance concrete's by using glass fibre and other admixtures in concrete up to certain proportions. In the view of the global sustainable developments, it is imperative that fibres like glass provide improvements in strength characteristics, durability, impact and serviceability of concrete. This paper presents an experimental investigation on the properties like workability and strength properties of glass fibre reinforced self-compaction concrete (GFSCC). The elimination of vibration for compacting concrete during placing through the use of self-compacted concrete leads to substantial advantages related to better homogeneity, enhancement of working environment and improvement in the productivity by increasing the speed of construction The resulting concrete is characterized in the fresh state by methods used for self-compacted concrete, such as, slump-flow, V-funnel and L-box tests, respectively. This paper concentrates mainly on studying the properties of GFSCC using alkali-resistant glass fibres in various proportions and comparing the same with the properties for controlled mixes of grade M 30 and M 35.

3 illus, 8 tables, 7 ref

003708   Senthamilkumar S;Natarajan C;Muthukumaran K (Civil Engineering Dep, Periyar Maniammai University, Vallam-613 403) : Field study on engineering properties of soil deposit in (Nagapattinam) coastal area for liquefaction analysis. J Instn Engrs-Pt CI 2008, 88(Feb), 30-6.

This paper focuses on the failures in coastal areas by performing a detailed study on the dynamic geotechnical properties with respect to the liquefaction potential of the deposits in the Coromandel coastal line of Nagapattinam town, Tamil Nadu, where major constructions related to the tsunami relief works and Sethu Canal Project are being undertaken over loose sandy deposits. It is mandatory to take into account the liquefaction-induced settlements and the lateral spread in the structural behaviour of harbour components and also the area grouped under zone III. In order to study, the dynamic geotechnical properties with respect to liquefaction-induced settlements, a series of field tests were conducted using Standard Penetration Test (SPT) and Cone Penetration Test (CPT) at 51 locations: From the results, a microzonation map for the liquefaction potential and its settlements, as well as correlations between settlement, relative density, mean particle size, factor of safety, coefficient of uniformity, coefficient of curvature, SPT and CPT for Nagapattlnam town have been proposed to help the planning and construction of the harbour and the allied structures.

5 illus, 20 ref

003707   Sengupta n (NO, , 15N Nellii Sengupta Sarani, New CMC Building (5th floor), Kolkata-700 087, Email: nsg1962@rediffmail.com) : Use of cost effective construction technologies in India to mitigate climate change. Curr Sci 2008, 94(1), 38-43.

Concentration of greenhouse gases play major role in raising the earth's temperature. Carbon dioxide, produced from burning of fossil fuels, is the principle greenhouse gas and efforts are being made at international level to reduce its emission through adoption of energy-efficient technologies. The UN Conference on Environment and Development, 1992 made a significant development in this field by initiating the discussion on sustainable development under the Agenda 21. Cost-effective construction technologies can bring down the embodied energv level associated with production of building materials by lowering use of energy-consuming materials. This embodied energy is a crucial factor for sustainable construction practices and effective reduction of the same would contribute in mitigating global warming. The cost-effective construction technologies would emerge as the most acceptable case of sustainable technologies in India both in terms of cost and environment.

6 illus, 1 tables, 7 ref

003706   Sengupta J B;Kumar S (Rigid Pavements Div, Central Road Research Institute, New Delhi) : Effect of flakiness indices on the properties of aggregate and cement concrete. Indian Highw 2008, 36(4), 57-62.

Flaky particles have larger specific surface area which results in higher demand of cement paste in cement concrete mix. Flat aggregate particles tend to impede compaction or break during rolling and decrease the strength of the pavement layer. More compacting effort is required as the percentage of flakiness and elongation indices increases. The effect of different percentage of flaky particles in aggregate ranging from 0 to 100, on the compressive and flexural strength of cement concrete and on the properties of aggregates, such as, bulk density, impact value, crushing value, water absorption and angularity number was studied. The Paper describes the present crushing system of aggregate to obtain the required shape and size. It is concluded from the study that there is negative effect of flaky particles on the strength properties of aggregate and cement concrete and a maximum limit of flaky particle shall be within 30 per cent of the aggregate for maintaining the quality of concrete.

8 illus, 5 tables, 6 ref

003705   Sen S (Consulting Engineering Services (I), Pvt Ltd., , Kokata) : Overloading in Bangladesh discussion and case study. Indian Highw 2008, 36(4), 43-50.

6 illus, 4 tables

003704   Sehgal R;Sharma A (Mechanical Engineering Dep, National Institute of Technology, Hamirpur-177 005, Email: rsehgal@nitham.ac.in) : Graphical approach for kinematic design and development of an automatic stamping machine using four bar chain. Indian J Engng Mater Sci 2008, 15(3), 229-35.

In paper, an attempt has been made to develop a stamping machine for making the labelling operation in any production line automatic. An inversion of the four bar chain with one link suitably shaped in the form of a stamp has been designed such that it labels each of the boxes present on the conveyor one by one. Though the stamping machine is not a new device and such devices have been made and are currently being used the world over, it is, the methodology of design used in this paper, which is rather unconventional. The mechanism has been designed graphically using the three position synthesis of four bar chain mechanism in which three positions of the coupler link of the mechanism have been fixed to carry out the synthesis. A prototype of the stamping machine has been fabricated and checked for smooth working.

13 illus, 1 table, 12 ref

003703   Saxena S C;Kumar V;Giri V K (NO, Thapar Institute of Engineering and Technology, Patiala, Punjab-147 004) : Non-arrhythmic ECG data compression using EBP-NN and feature extraction using wavelet transform. J Instn Engrs-Pt ET 2007, 88(July), 39-48.

Deals with an efficient algorithm which has been developed for data compression of non- arrhythmic electrocardiogram (ECG) using error back propagation neural networks (EBP-NN) and feature extraction using wavelet transform decomposition. Four EBP-NN have been trained to retrieve all the 12 standard leads of the ECG signal. The combination of leads and the network topologies have been finalized after an extensive study of correlation between the ECG leads using CSE database. Each network has a topology of N-4-4 -N, where N represents the number of samples in one cycle in any particular lead. It has been observed that this method compresses the data as well as improves the quality of retrieved signal due to elimination of high frequency noise. In this method- the compression ratio (CR) increases with increase in number of non-arrhythmic ECG cycles. This method- is best suited for data compression in Holter monitoring, ambulatory care and telemedicine. The performance of the algorithm has been evaluated by comparing the vital reference points (like onsets, offsets, amplitudes, durations) extracted features of diagnostic significance, section wise wave segments morphology analysis of the original as well as the reconstructed ECG signals. The wavelet transform has been used for QRS detection, which is used as the reference point for the extraction of diagnostic parameters. The test results are consistent and reliable and have proved beyond doubt that the EBPªNN method is very efficient for data compression and management of non - arrhythmic ECG signal for offline and online applications.

5 illus, 3 tables, 28 ref