022927   Muniu J M;Ikua B W;Nyaanga D M;Gicharu S N (Industrial & Energy Engineering Dep, Egerton Univ, Box-536-20115, Egerton, Kenya, Email: jmuniu@egerton.ac.ke) : Applicability of diatomite powder-mixed dielectric fluid in electrical discharge machining processes. Indian J pure appl Sci Technol 2013, 19(1), 19-36.

Electrical Discharge Machining (EDM) is a well-established non-contact machining technique for manufacturing geometrically complex shapes on hard but electrically conductive materials that are extremely difficult-to-cut by conventional processes. EDM has low material removal rate and Powder-Mixed Electrical Discharge Machining (PMEDM) is one of the latest techniques that has emerged to improve material removal rate and electrode wear ratio among other performance characteristics. - 288 - However, its utilization in the manufacturing industry is very low because many fundamental issues of this new development are not well understood. In this study, the performance of the PMEDM process was evaluated in terms of Material Removal Rate (MRR) and Electrode Wear Ratio (EWR) with respect to peak current and pulse-on time. Experiments were carried out at a duty cycle of 0.5, peak, current of 21A and pulse frequency of 10 KHz. Peak current and pulse-on time were varied from 3-21A and 45 - 135μs, respectively far pure (distilled water) and distilled water suspended with diatomite (powder-mixed dielectric fluid) at a concentration of 2 g/l. Graphite tool electrode was used to machine mild steel workpiece submerged in dielectric fluid. Each of the experimental set was conducted for 10 minutes and analysis of variances on MRR and EWR were performed using Statistical Analysis of System (SAS) software at 5% level of significance. Completely randomized design was used to plan and analyze the experiments which were performed on Toolcraft A25 sinker electrical discharge machine with retrofitted dielectric fluid circulation system. This study has found that variations of peak current and pulse-on time in diatomite powder-mixed dielectric fluid have significant influence on material removal rate and electrode wear ratio. Material removal rate increases to a maximum value in pulse-on time and then decreases with further increase in pulse-on time, while it increases with increase in peak current in both pure and diatomite powder-mixed dielectric fluids. Electrode wear ratio decreases to a minimum value with increase in peak current in pure dielectric, but remains fairly constant with further increase in peak current, while increase of peak current in diatomite powder-mixed dielectric has minimal effect on EWR throughout the range. Electrode wear ratio also decreases to minimum and then increases with further increase in pulse-on time. Future research based on these findings has been outlined.

13 illus, 5 tables, 13 ref

022926   Muduli P K;Das S K (Civil Engineering Dep, National Institute of Technology, Rourkela-769008) : CPT-based seismic liquefaction potential evaluation using multi-gene genetic programming approach. Indian Geotech J 2014, 44(1), 86-93.

This study examines the potential of multi-gene genetic programming (MGGP) based classification approach to evaluate liquefaction potential of soil in terms liquefaction index (LI) using a large database from post liquefaction cone penetration test (CPT) measurements and field manifestations. The database consists of CPT measurements; cone tip resistance (q _c ), friction ratio (R _f ), vertical total stress (σ _v ) and vertical effective stress of soil (σ _v '), seismic parameters; peak horizontal ground surface acceleration (a _max ) and earthquake moment magnitude (M _w), and the depth under consideration (z). The MGGP models (Model-I and Model-II) are developed for predicting occurrence and non-occurrence of liquefaction on basis of combination of above input parameters. The performance of the Model-I (95%) is found to be more efficient compared to available artificial neural network model (91%) and that of the Model-II (97%) is found to be at par with the available support vector machine model (97%) in terms of rate of successful prediction of liquefied and non-liquefied cases for testing data. Using an independent database of 96 cases, the overall classification accuracies are found to be 87 and 86% for Model-I and Model-II respectively. Sensitivity analyses are made to identify the important parameters contributing to the prediction of LI.

29 ref

022925   Mohammad Haniff M A S;Lee H W;Embong S S;Abd Azid I H (MEMS & NEMS Cluster, MIMOS Berhad, Technology Park Malaysia, Kuala Lumpur, Email: ishak@eng.usm.my) : Enhancing the performance of MEMS pressure sensors using 'v'-shaped piezoresistor-sensing elements. J scient ind Res 2014, 73(2), 107-11.

In this paper, the structural designs of piezoresistor sensing elements are analyzed using finite element analysis (FEA) software CoventorWare® to gauge their effects on the sensing characteristics of pressure sensors. The structural designs of interest include variations on geometrical parameters and material substitution on critical portion of piezoresistor. Results obtained indicate that reduction of the upper to lower piezoresistor width ratio and material substitution on the interconnection portion substantially improves the sensitivity and linearity of micro pressure sensor.

2 illus, 1 table, 21 ref

022924   Mishra R K;Roy P N S;Pandey J;Khalkho A;Singh V K (Mine Fire Div, Central Institute of Mining and Fuel Research (CIMFR), Dhanbad, Email: rkm.cmri@gmail.com) : Coal fire dynamics of Jharia coalfield using satellite data. Int J Geomatics Geosci 2014, 4(3), 477-84.

Jharia coalfield (JCF) is a treasure trove of the best quality prime coking coal of the country. In the present paper, study reveals the coal fire propagation of JCF during the period from 1990 to 2006 with the help of Landsat-5 TM and Landsat-7 ETM+ band 6 data. The Landsat-5 TM satellite thermal dataset acquired in the year 1990, 1994, 1996 and Landsat-7 ETM+ in 2006 were used to find out the lateral propagation. On the other side coal fire affected area has decreased during the said period confirmed by the field study.

8 illus, 1 table, 15 ref

022923   Maurya R M (NO, N.D. Agiculture and Technology Univ, Faizabad, Uttar Pradesh) : Management of water resources using "tora" optimization model. Wat Energy int 2013, 70(4), 42-51.

The management of irrigation water plays an important role in Sultanpur district's water availability in the eastern Uttar Pradesh of India. Optimal use of available surface and ground water, in any canal command area would result in their better utilization by maximizing the benefits from the crop production. The water demand and available water resources in the study area are evaluated considering surface and ground water. A simple economic - engineering optimization model is presented to explore the possibilities of conjunctive use of surface and ground water, using linear programming with various hydrological and management constraints to arrive an optimal cropping pattern for optimal use of water resources for maximizing net benefits. The "TORA-version 1.03" optimization package has been used to arrive at optimal allocation plan of surface water and ground water. The result indicates that conjunctive use options are feasible and can be implemented in the area, which would enhance the overall benefits from cropping activities.

8 illus, 6 tables, 32 ref

022922   Mary A D;Mathew A T;Jacob J (Electrical Engineering Dep, National Institute of Technology, Calicut, Kerala) : Robust H-infinity control approach of uncertain tractor trailer system. IETE J Res 2013, 59(1), 38-47.

This paper proposes a robust H-infinity control strategy for a differential drive Tractor with a single Trailer unit. This articulated vehicle being a complicated non holonomic system, the number of control inputs is less compared to the number of generalized coordinates. A linearized nominal model for this system is obtained by combining the kinematics and dynamics. A robust H-infinity output feedback control is designed using mu synthesis for the nominal plant when subjected to model uncertainties in unstructured form and output disturbances. Analysis on the robust uncertain closed-loop system is performed in both time and frequency domains. The simulation results indicating satisfactory stability and performance are presented. The step response and reference tracking are also found to be satisfactory.

10 illus, 1 table, 14 ref

022921   Mardaneh M;Golestaneh F (Electrical and Electronic Engineering Dep, Shiraz Technology Univ, Shiraz, Iran) : Harmonic optimization of diode-clamped multilevel inverter using teaching-learning-based optimization algorithm. IETE J Res 2013, 59(1), 9-16.

This paper proposes a harmonic elimination technique for online reducing harmonics in voltage source inverters. In the presented method, in order to provide required fundamental voltage and eliminate specified harmonics simultaneously, the value of the switching angles are determined using a new efficient optimization algorithm named Enhanced Teaching-learning-based Optimization (ETLBO). The efficiency of the presented strategy is validated on three-phase seven-level diode-clamped inverter while other structures of multi-level inverters (MLls) can be employed. The aim is to reduce the Total Harmonic Distortion (THD) in multilevel converter. In this paper, a new optimization algorithm named ETLBO has been successfully implemented to achieve optimal switching angles in order to harmonic elimination in MLIs. A three-phase seven-level diode-clamped MLI has been selected as a test case to validate the effectiveness of the proposed method. The simulation results demonstrated the ETLBO method not only is in preference to the Genetic Algorithm and Particle Swarm Optimization for including no user-defined parameter and simple implementation, but also for providing higher quality solutions. Moreover,-in order to verify the superiority of the ETLBO algorithm over conventional methods for harmonic elimination, the Newton-Raphson (NR) method was implemented to find optimal switching angles. The results obtained by the NR method compared with those of the ETLBO and the superiority of the ETLBO in terms of the both computational time and the resulted %THD was concluded. As a whole, the results show that the ETLBO algorithm is expected to become widespread in power systems where on-line updating harmonics is needed since it provide accurate and high-quality solution in extremely short time.

9 illus, 4 tables, 17 ref

022920   Malik J N;Shah A A;Naik S P;Sahoo S;Okumura K;Patra N R (Civil Engineering Dep, Indian Institute of Technology Kanpur, Kanpur-208 016, Email: javed@iitk.ac.in) : Active fault study along foothill zone of Kumaun sub-Himalaya: influence on landscape shaping and drainage evolution. Curr Sci 2014, 106(2), 229-36.

Kumaun Sub-Himalaya region is one of the most active regions falling into Seismic Zone V along the Himalaya. The geomorphology and drainage patterns in the area of active faulting and related growing fold provide significant information on the ongoing tectonic activity. The Kaladungi Fault (KF), an imbricated thrust fault of the Himalayan Frontal Thrust system - 285 - provides an excellent example of forward and lateral propagation of fault and related folding in both directions along the strike of the fault. The KF has displaced the distal part of the Kaladungi fan surface resulting into formation of south-facing active fault scarp with variable heights along the front. In the east, the uplifted fan surface is <126> 60 m, is comparatively higher in the central part with height of <126> 200 m and <126> 80 m high in the west. The variation in heights along the fault is attributed to lateral propagation of fault and associated fold in both directions (i.e. east and west) from the centre. These clearly testify displacement starting at nucleation in the centre and propagating laterally in an elliptical manner. The northwest and southeast propagation of KF has resulted into diversion of the Dabka and Baur rivers respectively. A marked diversion of the modern Dabka river along its present course from east to west can be traced between Shivlalpur and Karampur towns, covering a distance of about 10-12 km. Similarly, the Baur river is shifted from west to east by about 5-6 km between Kamola and Kaladungi towns. The diversion of Dabka and Baur rivers can well be justified by the existence of palaeo-wind-gaps through which these rivers flowed earlier during the recent past. The wind-gaps are characterized by about 0.5-1.0 km wide incised valley extending in NE-SW direction between Kaladungi and Karampur along the frontal zone.

7 illus, 45 ref

022919   Mahmoud M A A N (Civil Engineering Dep, Assiut Univ, Assiut 71516, Egypt, Email: mostafaabdo@yahoo.com) : Correlation of sandstone rock properties obtained from field and laboratory tests. Int J civ struct Engng 2013, 4(1), 1-4.

Unconfined compressive strength of rocks plays an important role in many practices for geotechnical engineering. It is used to determine the bearing capacity of soil specially rocks. The real value of this parameter requires a special technique such as undisturbed samples. So, prediction of unconfined compressive strength of sandstone rocks with the help of rock quality designation (RQD) provides a good opportunity to obtain this parameter without using of more laboratory tests. The RQD is commonly used for rock description or classification, and ... etc. Correlation of properties obtained from field and laboratory tests is considered the most important challenge for geotechnical engineers to save time, effort and many tests. This study was undertaken in order to quantify the variation of the values of unconfined compressive strength due to variation of (RQD). Many field boreholes have been investigated for this purpose. Unconfined compressive strength tests were conducted using samples of different values of RQD. This paper proposed a new empirical equation to predict the unconfined compressive strength for sandstone rock.

9 illus, 1 table, 9 ref

022918   Mahgoub S E (NO, Hydraulics Research Institute, National Water Research Center, Egypt, Email: s_mahgoub@hri-egypt.org) : Bed configuration on sandy bed channel. Int J civ struct Engng 2013, 4(1), 72-86.

Main objective of this study is to investigate the effect of different flow parameters, mainly flow discharge and Froude number on bed configuration upstream and downstream of hydraulic jump. Bed regression was studied at different Froude numbers ranging from 0.05 to 19. The sand used in the experiments was natural and sieving analysis was tested where grain size diameter was found to be 0,4 mm at 60% passing. This experiment study was conducted at the - 284 - Hydraulics Research Institute (HRI), the National Water Research Center (NWRC), employing two different rectangular flumes with different capacities and dimensions. Therefore, different velocities; different depths and thus different Froude numbers were obtained. The two sides of the flumes are made of glass to facilitate visualizing and monitoring the bed configuration. Extensive field observations on sediment movements in movable bed flume have been carried out for estimating the bed roughness in river channels. Seventy two runs were executed at different discharges started from 0.02 to 0.130 m³/s with an increment of 0.01 m³/s where each discharge has six different gate openings to get all characteristics of bed configuration. The experimental investigation showed that at low unidirectional velocities (≤0.50 m/s), increasing the flow caused the bed to evolve from small-scale symmetric ripples to large-scale symmetric ripples to dunes and later to plane bed. At higher velocities (<62>0.50 m/s), a similar trend was observed, but ripples were more asymmetric and moved to standing waves and then anti-dunes. Two phase diagrams are presented, the first diagram at Fr <60>1 and the second at Fr <62>1 to summarize the observed relationships of bed configurations to flow conditions. These diagrams assist in the interpretation of bed configuration characteristics.

6 illus, 3 tables, 11 ref

022917   Lokhande B J;Ambare R C;Mane R S;Bharadwaj S R (NO, School of Physical Sciences, Solapur Univ, Solapur-413 255, Email: bjlokhande@yahoo.com) : Potential specific capacitance in layered nickel ferrite electrochemical supercapacitors. Invertis J renewable Energy 2013, 3(2), 79-88.

Nickel ferrite electrodes for electrochemical supercapacitors were made from a successive ionic layer - adsorption and reaction (SILAR) chemical method. Their structural elucidation and morphological evolution studies were made and further investigated in electrochemical cydic-voltammetry characteristic measurement. Face-centered cubic crystal structure of nickel ferrites composed of several irregular islands is confirmed. Brief flow chart is discussed for clear in-depth understanding, of the formation nickel ferrite. Due to a significant reversible pseudocapacitive contribution nickel ferrite electrochemical supercapacitor contributes 555.5 F/g specific capacitance at 2 mV/s. Electrochemical impedance analysis measurement, along with an equivalent circuit details, is also provide for understanding the charge transport kinetics across various interfaces.

8 illus, 2 tables, 24 ref

022916   Kohli N K;Ahuja E (Faculty of Engineering, Mechanical Engineering Dep, JJT Univ, Jhunjhunu, Rajasthan, Email: navinkkohli@gmail.com) : HAWT power enhancement using its characteristics. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1), 1-7.

The basic objective of the study is efficient performance wind turbine with a highest possible annual usable energy pattern factor and least possible dimension, getting the maximum wind energy (kWh) and producing the maximum power in MW. The impact of these performance parameters on the HAWT rotor geometry has been investigated. The variation patterns of aerodynamic and geometric parameters are obtained, analyzed and discussed. The same then compared with each other and with the existing large capacity HAWT machines of reputed manufacturers. This study analysis and its results can be a basis for evaluating aerodynamic performance of large capacity HAWT wind turbine. The current study provides a detail configuration of wind turbine blade design that indicates dominance of modern HAWT which is for use of horizontal axis rotors.

7 illus, 5 tables, 55 ref

022915   Kim K W;Lee W J (NO, College of Engineering, Dankook Univ, Korea, Email: nirkim@gmail.com) : Low-complexity parallel and serial systolic architectures for AB<. IETE Tech Rev 2012, 30(2), 134-41.

Efficient arithmetic is essential for fast implementation of cryptographic applications based on finite fields. This paper presents a new parallel systolic AB² multiplier for exponentiation in GF(2^m) that has a low cell delay and high throughput. In addition, a serial systolic AB² multiplier that can be applied well in space-limited hardware is presented. Thus, exponentiation can be implemented more efficiently by repeatedly applying AB² multiplication rather than AB multiplication. The proposed parallel (serial) multipliers produce the results at a rate - 283 - of one per 1 (m/2) cycles with a latency of 2m + m/2-1 (2m + m/2 - 1) cycles using O(m³)(O(m²)) area-time complexity. As compared to related works, both multipliers have lower area-time complexity, cell delay and latency and higher throughput and include the features of regularity, modularity, unidirectional dataflow and local interconnection.

5 illus, 2 tables, 15 ref

022914   Kim H (Cyber Security Dep, Kyungil Univ, Korea, Email: kim@kiu.ac.kr) : Privacy preserving security framework for cognitive radio networks. IETE Tech Rev 2012, 30(2), 142-8.

To address the ever-increasing demand for wireless bandwidth, cognitive radio networks (CRNs) have been proposed to improve the efficiency of channel utilization. CRN permits unlicensed users to utilize the idle spectrum as long as it does not introduce interference to the primary users due to the Federal Communications Commission's recent regulatory policies. In this article, we first identify the security challenges on CRNs. Then, we present main security issues together with privacy issues on CRNs and provide a privacy preserving security framework as a potential solution. The proposed framework provides a privacy preserving yet accountable security among the CRN entities. Finally, we suggest directions of future work on secure CRNs by describing several open issues.

2 illus, 1 table, 21 ref

022913   Kharazi S M S S;Sahbudin R K Z;Abas A F;Ahmad Anas S B (Computer and Communication Systems Engineering Dep, Faculty of Engineering, Putra Malaysia Univ, 43400 UPM Serdang, Selangor, Malaysia, Email: s.seyyedzadeh@gmail.com) : Fiber non-linear effects in multiple-wavelengths optical CDMA systems. IETE Tech Rev 2012, 30(2), 149-56.

Multi-wavelength Optical Code Division Multiple Access (OCDMA) systems suffer from fiber impairments including non-linear effects (NLE), especially when the number of wavelengths and input power level increase. In this paper, a review of NLE, including self-phase modulation, cross-phase modulation, four wave mixing (FWM), stimulated Brillouin scattering and stimulated Raman scattering on the system performance of OCDMA systems is presented. As some of the non-linearities may have correlated effects on the performance of the system, the relations between these effects are also investigated. Bit error rate results reveal that the most important unwanted effect was caused by FWM.

17 illus, 28 ref

022912   Khanzadi H;Eshghi M;Borujeni S E (Electrical Engineering Dep, Shahid Beheshti Univ, Tehran, Iran Evin 1983963113, Tehran) : Design and FPGA implementation of a pseudo random bit generator using chaotic maps. IETE J Res 2013, 59(1), 63-73.

In this paper, a random bit sequence generator based on chaotic maps is introduced and implemented. In this generator, two chaotic map functions with two different keys are used. The Bifurcation diagram is used to calculate the initial state of the chaotic maps in order to produce the output random bit sequence. Chaotic Logistic and Tent maps classically are defined in an analogue space. In order to implement these chaotic maps on a hardware digital platform, these - 282 - chaotic maps are modified. Digital chaotic Logistic and Tent maps are introduced. A design for implementation of these modified chaotic maps is also presented. The output bits of two chaotic maps are EX-ORed to produce a random sequence of 1000 000 bits. These designs are implemented on Field Programmable Gate Array, and the results are reported. The proposed designs are tested by producing 100 samples of 1 000 000 bits, and they pass the standard Federal Information Processing Standard 140-1 and National Institute of Standards and Technology statistical tests for random bit generators.

17 illus, 7 tables, 20 ref

022911   Khanna N;Jagannatham A K (Electrical Engineering Dep, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh) : Optimal frame rate allocation and quantizer selection for unicast and multicast wireless scalable video communication. IETE J Res 2013, 59(1), 23-37.

This paper, present novel schemes for video quality maximization in the context of H.264 scalable video coding-based 4G wireless broadcast and multicast video transmission to heterogeneous multimedia wireless clients. In the first part, we address the issue of optimal frame rate allocation when the multimedia server is constrained by the processing overheads required for tasks such as video encoding, bit-stream extraction, packetization, etc. and demonstrate that the above problem of perceptual quality maximization is well represented by a constrained optimization framework. Based on the system model, we present a closed-form solution for frame rate allocation and a comprehensive algorithm for sum quality maximization. In the second part, we propose a novel rate partitioning-based optimal scalable video (RPSV) transmission framework. A typical wireless multicast group comprises of multimedia clients with varying wireless link qualities. Conventional multicast video transmission is constrained by the broadcast/multicast group (BMG) subscriber with the worst link capacity. Hence, we propose the RPSV scheme for optimal partitioning of the multicast group for transmission of the H.264-coded base and enhancement scalable video layers. We demonstrate that the optimal wireless link quality-based BMG partition and the associated quantization, time-fraction parameters can be computed by solving a series of convex objective minimization problems and derive a closed-form solution for the convex problem at each step. We compare the results obtained using the above mentioned optimal frame rate allocation and quantization parameter selection schemes with the results obtained using conventional schemes and demonstrate the superiority of the proposed algorithms in both unicast and multicast scenarios.

15 illus, 2 tables, 14 ref

022910   Katiyar H (Electronics and Communication Engineering Dep, BBDU, Lucknow, Uttar Pradesh) : Outage performance of two multi-antenna relay cooperation in rayleigh fading - 281 - channel. IETE J Res 2013, 59(1), 4-8.

Cooperative relaying exploits the broadcast nature of wireless channel and extracts spatial diversity in distributed manner. In this paper, we investigate the performance of an infrastructure-based multi-antenna relay network in absence of direct link. A closed-form expression of outage probability has been derived when the cooperating relays coherently combine the received signals and destination select the best copy of the received signals. The effect of number of relay antennas and relay placement on the system performance has also been studied.

5 illus, 22 ref

022909   Karthikeyan S;Elango A;Prathima A (Mechanical Engineering Dep, Syed Ammal Engineering College, Ramanathapuram-623 502, Email: kamalipaper@gmail.com) : Diesel engine performance and emission analysis using canola oil methyl ester with the nano sized zinc oxide particles. Indian J Engng Mater Sci 2014, 21(1), 83-7.

In this study, the performance, combustion and exhaust emission characteristics of single cylinder, four stroke, stationary, air-cooled and direct injection compression ignition engine have been investigated at the constant engine speed 1500 rpm under the full load when it is fueled with various blends such as 80% diesel + 20% canola oil methyl ester, 80% diesel + 20% canola oil methyl ester + 50ppm zinc oxide and 80% diesel + 20% canola oil methyl ester + 100ppm zinc oxide. And also the properties such as pour point, cloud point, flash point, kinematic viscosity, cetane number, sulphated ash and calorific value of above blends are determined and compared with American biodiesel standards (ASTM D7467). It is found that the addition of zinc oxide nanoparticles which accelerates early ignition of combustion shortens ignition delay and enhances NOx emissions.

6 illus, 1 table, 15 ref

022908   Julias A A;Mohmeed S A;Murali V (Mechanical Engineering Dep, B S Abdur Rahman Crescent Engineering College, Chennai-600 048, Email: juliasarok@gmail.com) : Effect of delamination on buckling strength of unidirectional glass-carbon hybrid laminates. Indian J Engng Mater Sci 2014, 21(1), 23-9.

Experimental study is designed to understand the effect of delamination on critical buckling load and mode of failure for glass/carbon hybrid laminates. Firstly, delaminated specimens are compressed using a universal testing machine and buckling tests performed after the ends of each specimen are hinged to a special fixture designed to permit rotational boundary conditions. Non-linear buckling analysis based on incremental iteration method is conducted using finite element analysis (FEA) package (ANSYS) after conducting tensile tests to find the material properties. Critical buckling loads are found for symmetric [C0/G45/G-45/G90]s and anti-symmetric [C0/G45/G-45/G90//G90/G45/G-45/C0] laminate configurations with four different delamination lengths (a/L= 0.2, 0.3, 0.4 and 0.5) created at two different delamination positions (t/h = 0.5 and 0.25). In this study, the critical buckling load decreased as the delamination length increased. Moreover, the critical buckling load tended to decrease when the delamination approached the surface.

16 illus, 13 ref

022907   Jin C;Cho S H (Electronics and Computer Engineering Dep, Hanyang Univ, Seoul-133 791, Korea) : Enhanced collision detection scheme for ISO 18000-6C RFID systems. IETE Tech Rev 2012, 30(2), 108-19.

In radio-frequency identification systems, tag collision resolution is a significant issue for fast tag identification. Dynamic framed slotted ALOHA (DFSA) is one of the most widely used algorithms to resolve tag collision. Collision detection (CD) plays an important role in determining the efficiency of DFSA-based algorithms because most DFSA-based algorithms determine the next frame size according to the number of collided slots in the current - 280 - frame. Existing CD methods do not respond quickly enough to detect a collision and have difficulty in distinguishing a collision from noise, resulting in a degradation of system efficiency. This paper presents a CD scheme based on the ISO/IEC 18000-6C protocol to improve CD efficiency. This scheme enables fast and accurate CD by detecting the number of pulses transmitted by tags. The effectiveness and practical feasibility of the scheme is verified by simulation and implementation. Performance evaluation results show that the proposed scheme achieves faster identification speed than the conventional methods, especially under noise conditions.

13 illus, 7 tables, 33 ref

022906   Jegan Lal G;Jayesh P;Thyagarajan K (Cryo Structures and Tanks Div, Liquid Propulsion Systems Centre, Indian Space Research Organisation, Thiruvananthapuram-695 547, Email: jeganlal_isro@yahoo.com) : Burst pressure estimation of reworked nozzle weld on spherical domes. Indian J Engng Mater Sci 2014, 21(1), 88-92.

Propellant tanks of rockets or launch vehicles have nozzles welded to their domes as interfaces for valves or pressurisation/vent lines. These nozzle welds are critical since more often the failure happens here when the tank is pressurised. The considerable difference between the yield and ultimate strength of weld as compared to the parent material is the reason for the low burst pressure of the nozzle welds. To eliminate unacceptable weld defects like porosities, cracks etc., the defective portions are rewelded and are called weld reworks. Residual stress present because of rework, further reduces the burst pressure. In this study, burst pressure estimation of a typical nozzle welded to the dome is analysed by finite element method. The effect of geometric non-linearity of the structure in the prediction of burst pressure is clearly brought out. Also, the burst pressure reduction when weld reworks are carried out in a portion of the weld length and reduction in burst pressure when this rework length increases is demonstrated using finite element analysis.

13 illus, 2 tables, 9 ref

022905   Jayashree S M;Bharatwaj R R;Helen Santhi M (NO, School of Mechanical and Building Science, VIT Univ, Chennai, Email: jayashree.1610@gmail.com) : Dynamic response of a space framed structure subjected to blast load. Int J civ struct Engng 2013, 4(1), 98-105.

This paper investigates the dynamic response of a space framed structure due to blast load. An explosion due to blast load can cause devastating damage on the building causing collapse of entire structure and loss of human life. Studies have been conducted on the dynamic response of structures to blast load. These studies generally help in enhancing the understanding of structural behavior to blast load. In this paper an attempt has been made to use Slurry Infiltrated Fiber Reinforced Concrete (SIFCON), a type of FRC with high fiber content as an alternative material to Reinforced Cement Concrete (RCC). SIFCON has high energy absorption capacity, higher strength and it is highly ductile. Space framed models are developed and time history analysis is carried out for blast load using the software package SAP 2000. The properties of SIFCON and RCC are derived from the experiments. The dynamic characteristics such as fundamental frequency, mode shapes are evaluated. The displacement time history response of frames with SEFCON and RCC due to blast load is compared. The results showed that the reduction in the displacement of about 25-30% is achieved using SIFCON.

13 illus, 2 tables, 9 ref

022904   Jain A;Sharma D K;Gupta A K;Hannurkar P R; Pathak S K (NO, Raja Ramanna Centre for Advanced Technology (RRCAT), Indore-452 013, Email: ajain@rrcat.gov.in) : Compact solid state radio frequency amplifiers in kW regime for particle accelerator subsystems. Sadhana 2013, 38(4), 667-78.

Radio frequency and Microwave (RFM) infrastructure test facility is under development at RRCAT for evaluating and powering, subsystems of particle accelerator. As a part of this facility, design of 20-30 kW UHF solid state power amplifiers is in progress. For this work, design procedure has been formulated for the development of solid state amplifier modules, radial combiner, divider and directional coupler; with specifications suited to RFM power system for particle accelerator. Methodology has been demonstrated by developing two different compact amplifiers with power output of 2 kW each, operating at 352 MHz and 505.8 MHz, respectively. This paper describes underlying design principles and indigenous development of these amplifiers, consisting of 270-300 W amplifier modules, 8-way 2 kW radial combiner/divider and directional couplers. Design methodology for power combiner has been extended by physically realizing higher power (4 kW) 16-way power combiner and 2-way combiner (8 kW) for higher power (8 kW) amplifier configuration planned. Simple design, indigenous technology, high efficiency and ease of fabrication, are the main features of this design.

15 illus, 22 ref

022903   Hitit A;Talas S;Kara R (Materials Science and Engineering Dep, Afyon Kocatepe Univ, 03200 Afyonkarahisar, Turkey, Email: hitit@aku.edu.tr) : Effects of silicon and chromium additions on glass forming ability and microhardness of Co-based bulk metallic glasses. Indian J Engng Mater Sci 2014, 21(1), 111-5.

Effects of silicon and chromium additions on glass forming ability (GFA) and microhardness of a Co-Fe-Ta-B bulk metallic glass are investigated by using differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). It is found that partial substitution of boron by silicon promotes the GFA of the alloy. Fully amorphous rod of 4 mm is fabricated by suction casting Co₄₃Fe₂₀Ta_5.5B_26.5Si₅ alloy. However, partial replacement of cobalt by chromium decreased the GFA significantly. In fact, critical casting thickness of Co₃₉Cr₄Fe₂₀Ta_5.5B_26.5Si₅ alloy is determined as 2 mm. It is also determined that microhardness values of the amorphous alloys are about 1200HV₃₀₀. This value is lower than the hardness of the base alloy,1455HV₃₀₀, and it is believed that decrease in hardness results from the reduction in boron contents of the alloys.

4 illus, 1 table, 24 ref

022902   Hiremani V A;Jadhav S S (Computer Dep, Alard College of Engineering and Management, Pune, Email: vani.hiremani@gmail.com) : Context-free protocol and N-ACK scheme for secure routing in MANET. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1), 60-4.

Mobile Ad hoc Networks (MANETS) are transient networks of mobile nodes, connected through wireless links, without any fixed infrastructure or central management. Due to the self-configuring nature of these networks, the topology is highly dynamic. In general, routing protocols for MANETs are designed based on the assumption that all participating nodes are fully cooperative. Wireless Mobile ad hoc Networks suffer from a great efficiency loss due to the individual nodes that are constrained by the resources such as battery power and bandwidth. Misbehaving nodes makes the routing process a tedious task. One such routing misbehaviour is that some selfish nodes will participate in the route discovery and maintenance processes but refuse to forward data packets. A threat to such multihop transmission is posed by selfish nodes, which may drop others packets to save their own bandwidth and battery life. Therefore, packet forwarding is a fundamental problem for wireless ad hoc networks. This proposed method implements a context-free protocol that does not rely on observation and selfish behavior detection. - 278 - Given a path, a context-free protocol can transmit packets through it without knowing whether the intermediate nodes are selfish or not. In this method, the data of a packet should be encrypted and the identity of the destination should only be revealed after all nodes forwarded the packet cooperatively. Multi hop acknowledgement N-ACK is used in this scheme to detect misbehaving nodes.

4 illus, 14 ref

022901   Hemrajani N (NO, JECRCU, Jaipur, Rajasthan, Email: naveen.hemrajani@jecrcu.edu.in) : Sustainable approach for analyzing load testing tools. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1A), 17-24.

Software testing is a process used to identify the correctness, completeness and quality of developed computer software. Although crucial to software quality and widely deployed by programmer and testers, software testing still remains an art, due to limited understanding of the principles of software. The objective of this research paper is to evaluate and analyze the performance of some testing tools and compare them to determine their effectiveness and reliability, used in software testing. In this research paper, two testing tools: WAPT and NEOLOAD are described, Which are implemented on a web application. WAPT is a load, stress testing tool that provides an easy to use & cost effective way to test any website. Whereas, the NEOLOAD is a tool that measures performance and behavior of the system under load. The performance of these testing tools is evaluated and compared and their results will help in adoption and usage of these tools.

8 ref

022900   Hasan L;Taouil M;Zafar H (Computer Systems Engineering Dep, Engineering and Technology Univ, Peshawar, Pakistan) : Performance evaluation for field programmable gate array-based bioinformatics sequence alignment. IETE J Res 2013, 59(1), 17-22.

Sequence alignment is a computationally expensive activity in bioinformatics that can benefit significantly from Field Programmable Gate Array-based high-performance computing systems. This paper evaluates the performance of such systems for bioinformatics sequence alignment applications considering various parameters like data bus width (W), the number of processing elements, and the maximum operating frequency.

4 illus, 6 tables, 10 ref

022899   Hari Dev;Singh R;Sengupta C K (NO, Central Soil and Materials Research Station, Hauz Khas, New Delhi, Email: haridev@nic.in) : Rock supports and geological appraisal for head race tunnel of Tata hydroelectric project, Bhutan. J Rock Mech Tunnelling Technol 2013, 19(1), 29-46.

This paper presents geological appraisal and the rock support systems adopted during excavation of the head race tunnel of Tala hydroelectric project in Bhutan. Rock supports in terms of steel fibre reinforced shotcrete (SFRS), grouted rock bolts, self-drilling anchors and steel ribs were provided for supporting the excavation. Finally, the tunnel was supported with concrete lining. Apart from this, contact and consolidation grouting was also done for improving the properties of rock mass. The rock mass class encountered during the excavation varied from good quality to squeezing condition. The support system was designed for different classes of rock mass and the same was implemented with some modifications as per the site conditions. DRESS technique was used. The extensive quality control and instrumentation - 277 - were helpful to take the corrective measures, wherever required.

16 illus, 5 tables, 12 ref

022898   Gupta P;Meena Y K (Computer Science & Engineering Dep, AIM & ACT, Banasthali Univ, Jaipur, Rajasthan, Email: prashaligupta.15@gmail.com) : Sentence based scoring method for extractive document based summarization review. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1A), 32-6.

Text Summarization is the process of reducing a text document in order to create a summary that retains the most important points of the original document. Text summarization can be single document text summarization and a multi document text summarization. This paper contains a large literature review in the research field of Text Summarization. In this paper we study about the single document text summarization. Here we study statistical or linguistic sentence scoring methods. Scoring sentence is extracted using different methodologies. Also study different type of summaries. Evaluate the summary using the ROUGE method. It is standard method for evaluating the system generated summary with the human generated summary.

1 table, 27 ref

022897   Govindaraj M;Shukla C (NO, , Crompton Greaves Ltd.) : Over view of short circuit analysis and challenges in the development of 1200 KV auto transformer. Wat Energy int 2013, 70(4), 9-11.

8 illus, 4 tables, ref

022896   Gopalakrishnan R;Krishnan A (Electrical and Electronics Engineering Dep, K S Rangasamy College of Technology, Tiruchengode-637 215, Email: gopsengr@gmail.com) : Efficient technique to solve combined economic and emission dispatch problem using modified ant colony optimization. Sadhana 2013, 38(4), 545-56.

Economic load dispatch is one of the vital purposes in electrical power system operation, management and planning. Economic dispatch problem is one of the most important problems in electric power system operation. In large scale system, the problem is more complex and difficult to find out optimal solution because it is nonlinear function and it contains number of - 276 - local optimal. Combined economic emission dispatch (CEED) problem is to schedule the committed generating units outputs to meet the required load demand at minimum operating cost with minimum emission simultaneously. The main aim of economic load dispatch is to reduce the total production cost of the generating system and at the same time the necessary equality and inequality constraints should also be fulfilled. This leads to the development of CEED techniques. There are various techniques proposed by several researchers to solve CEED problem based on optimization techniques. But still some problems such as slower convergence and higher computational complexity exist in using the optimization techniques such as GA for solving CEED problem. This paper proposes an efficient and reliable technique for combined fuel cost economic optimization and emission dispatch using the Modified Ant Colony Optimization algorithm (MACO) to produce better optimal solution. The simulation results reveal the significant performance of the proposed MACO approach.

2 illus, 7 tables, 24 ref

022895   Geetha Priya M;Baskaran K (Electronics and Communication Engineering Dep, Amrita Vishwa Vidyapeetham, Coimbatore-641 112, Email: geetha.sri82@gmail.com) : New universal gate for low power SoC applications. Sadhana 2013, 38(4), 645-51.

This paper formulates a new design technique for an area and energy efficient Universal NAND gate. The proposed robust three transistors (3T) based NAND gate is just as effective for dynamic power control in CMOS VLSI circuits for System on Chip (SoC) applications. The 3T NAND gate is intuitively momen-tous and lead to better performance measures in terms of dynamic power, reduced area and high speed while maintaining comparable performance than the other available NAND gate logic structures. Simulation tests were performed by employing standard Berkeley Predictive Technology Model (BPTM) 22 nm, 45 nm and 90 nm process technologies. The experiment and simulation results show that, the proposed 3T NAND gate effectively outperforms the basic CMOS NAND gate with excellent driving capability and signal integrity with exact output logic levels.

6 illus, 2 table, 10 ref

022894   Gautam P P (Civil Engineering Dep, Madhav Univ, Abu Road, Email: gautampharshita@gmail.com) : Planning of residential & industrial construction technology. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1A), 46-8.

Construction Technology will raise the sector to a higher world beating level of performance and competitiveness. This will be achieved by analysing the major challenges that the sector faces in terms of society, sustainability and technological development. Research and innovation strategies will be developed to meet these challenges engaging with and mobilising the wide range of leading skills, expertise and talent available to us within our industry over the coming decades, in order to meet the needs of the Society.

21 ref

022893   Gautam A;Jogdand S V;Patel B (Farm Machinery and Power Engineering Dep, Punjab Agricultural Univ, Ludhiana-141 004, Email: anand-coaefpm@pau.edu) : Development and evaluation of bullocks drawn multipurpose tool carrier suitable for the eastern plateau. Prabandhan: Indian J Mgmt 2014, 7(1), 45-51.

The Multipurpose Tool Carrier (MPT) was developed to prepare - 275 - the seed bed in dry and wet soil conditions and to perform various other agricultural operations. Various field operations can be performed with the help of the multipurpose tool carrier (MPT) with minimum investments of time and money. The average field capacity of the attachments, that is, cultivator (with shovel and sweep) and seed drill for dry field were found to be 0.1385,0.1263, and 0.1758 ha/h. It gave higher field capacity (1 ha/day) with additional savings in the cost of operation. The operational cost of MPT cultivator (with shovel and sweep) and seed drill were found to be 551.54,415.83, and 622.97 Rs. /ha respectively in comparison to the Tendua plough. It was observed that the use of MPT is much economical than the traditional methods. The fabrication cost of MPT with attachments (cultivator with shovel, sweep, and seed drill) was about Rs. 8000.

2 illus, 3 tables, 11 ref

022892   Ganesh Kumar S;Robinson R G;Rajagopal K (Geotechnical Engineering Div, Civil Engineering Dep, Indian Institute of Technology Madras, Chennai-600 036) : Improvement of soft clays by combined vacuum consolidation and geosynthetic encased stone columns. Indian Geotech J 2014, 44(1), 59-67.

Use of stone columns is one of the proven ground improvement techniques for improving the load carrying capacity of soft clay deposits. When the stone columns are installed in soft clays, there is a possibility of intrusion of fine clay particles into the column which reduces the shear strength of the stones resulting in reduction in capacity. Geosynthetic encasement has been adopted by several investigators in order to enhance the load carrying capacity. The capacity of the stone column may be further increased if the undrained shear strength of the surrounding soft soil is improved. In the present study, the possibility of applying the vacuum through encased stone column for improving the strength of soft clay soil is explored through laboratory model tests. It was observed that both stiffness and load carrying capacity of the column increased significantly after the application of vacuum suggesting that the proposed method is a viable ground improvement option.

18 ref

022891   Gandhimathi R;Ramesh S T;Sindhu V;Nidheesh P V (Civil Engineering Dep, National Institute of Technology, Tiruchirappalli-620 015, Email: rgmathii@nitt.edu) : Removal characteristics of basic dyes from aqueous solution by fly ash in single and tertiary systems. J scient ind Res 2014, 73(4), 267-72.

The use of fly ash as a low cost adsorbent for the removal of three basic dyes from their single and tertiary aqueous solution has been investigated. Batch adsorption experiments were conducted to determine the effect of contact time and adsorbent dosage on adsorption of dyes from aqueous solution. The adsorption isotherm results indicated that the Freundlich adsorption isotherm fitted the data better than the Langmuir adsorption isotherm. The adsorption capacity of fly ash decreases in tertiary system as compared to single system indicates the competitive sorption behaviour of fly ash. Kinetic parameters of adsorption such as the pseudo first order constant and pseudo second order constant were determined. The results of the study demonstrated that the fly ash could be used as an effective low cost adsorbent for the removal of basic dyes from aqueous solution.

4 illus, 4 tables, 20 ref

022890   Gadhe A A;Sonawane S S;Varma M N (Chemical Engineering Dep, Visvesvaraya National Institute of Technology (VNIT), Nagpur-440 010, Email: shriramsonawane@gmail.com) : Evaluative report of fermentative hydrogen production: current prsopective and way forward. Invertis J renewable Energy 2013, 3(2), 106-17.

Hydrogen, the most abundant and lightest element in the universe with high conversion efficiency, recyclability and non-polluting nature illustrate its enormous potential as a future energy. Dark fermentative hydrogen production is an attractive route to the renewable production of hydrogen for its inherent advantages over other routes. At least in its initial employment, dark fermentation would use readily available waste streams as a substrate. Various microorganisms are explored for - 274 - producing hydrogen by exploiting the variety of biological organic substrates. The metabolic pathways involved are well understood and are reviewed here. A large amount of research has focused on factors affecting of dark fermentation process and hence, the main factors influencing the fermentative hydrogen production and the advances in the research of the effect were briefly introduced and discussed. Furthermore, different strategies to extract more hydrogen or energy have been proposed, followed by review of current progress in this direction.

1 illus, 3 tables, 75 ref

022889   Esubalew E T;Sharma N (Water Resource Development and Management Dep, II, Roorkee) : Numerical model applications for sedimentation and flushing behaviour of storage reservoir- case study. Wat Energy int 2013, 70(4), 52-9.

The HEC_RAS model was employed for estimation of reservoir sedimentation and for assessment of strategies of its flushing behavior of Luhri reservoir on a daily basis. Once all parameters are set within their effective ranges, the simulations of HEC-RAS model perform well and the results are much resembled to the observed set of conditions. As the preceding discussion indicates, Engelund-Hansen transport function gives best result for the present study in predicting the sediment load compared with other available transport functions in the model. Besides, the fall velocity is predicted well by the Van Rijn equation in this study.

11 illus, 15 ref

022888   Doshi N;Sheth B;Dave J (Mechanical Engineering Dep, Nirma Univ, Ahmedabad, Email: naman.doshi.7@gmail.com) : Development of an oil spill mitigation system. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1), 103-6.

The paper is regarding the project which aims to minimise the time of mitigating this disaster by deploying cheap, efficient oil cleaning robots in large numbers. At first, the concentration was based upon building a mechanism by breaking emulsions of oil and then recovering the oil. The concept, however proved to be better at a macro level, which deviates from the objective. The other mechanism used is that of sorbents to absorb the oil. Thecurrent practice involves using sorbents as a tail for boats. Suited for one run. The mechanism discussed continuously uses the sorbent up till its optimum life cycle. The model developed can also be used as an appendage that can be scaled to fit at the rear of boats or customized as per the marine vehicle with which it is to be used. The model entails the use of a poly urethane foam as a conveyor belt. The oil is absorbed by PUF and squeezed out at the end of the cycle. The recovered oil is taken and stored in the storage tank. The most ideal material is the graphite foam developed at Rice University, but taking into consideration the cost and availability, it has the dual advantage of using it as efficient means to recover oil, as well as, by burning it at the end of its life cycle energy can be obtained.

4 illus, 3 ref

022887   Dimon S (NO, Monash Univ, VIC, Australia, Email: steve.dimon3@gmail.com) : Design of micro opto-mechatronics system. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1A), 1-3.

Basic assumption for the design of mechatronic devices is the acquisition by the device itself which is responsible for the lower levels of the process (task) to allow the user to focus on higher-order functions. Mechatronic device structure can be considered at two levels: abstract, consisting of the conjunction of partial functions of the main function device and the specific plane, consisting of the combined structural parts and assemblies, which are natural carriers of various functions involved. The integration of mechatronic device - 273 - structure is a result of links among 'smart' teams which communicate and cooperate. The linking mechanical structure, sensors, actuators and information processing occur as a result of mass flow of streams, of energy and information.

022886   Dharrao A B;Ganorkar S R (Electronics and Telecommunication Dep, Sinhgad College of Engineering, Vadagaon (Bk), Pune Univ, Pune-411 041, Email: aniket.dharrao11@rediffmail.com) : Iris occlusion estimation method. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1), 29-34.

This paper presents a theoretical analysis of an Iris occlusion estimation method. Iris masks play an important role in iris recognition. Iris mask indicate which part of the iris texture map is useful and which part is occluded (contaminated) by noisy image artifacts such as eyelashes, eyelids, eyeglasses frames and specular reflections. The accuracy of an iris mask plays an important role in iris recognition system. The performance of recognition system decreases when iris mask is inaccurate even if best recognition algorithm is used. We propose to use Figueiredo and Jain's Gaussians mixture models (FJ-GMMs) to model the underlying probabilistic distributions of both valid and invalid region in iris images.

13 illus, 13 ref

022885   Datta D;Chakraborty S (NO, West Bengal State Electricity Distribution Co. Ltd., Kolkata) : Meeting peak power requirement in the eastern regional grid vis-a-vis development of pumped storage projects. Wat Energy int 2013, 70(4), 35-7.

4 illus, 1 table, ref

022884   Das S;Misra P;Vignesh G;Srivastava S B;Gahlot R;Agarwal N (NO, Corporate R & D, Moser Baer India Ltd., Greater Noida, Email: sthitadhi.das@moserbaer.net) : Study on the effect of concentration, pH and temperature on the CdS film thickness deposited by CBD process. Invertis J renewable Energy 2013, 3(2), 118-24.

In this study authors have found the relation of pH, temperature and concentration of CdCl₂ and thiourea on the film thickness. The thickness of CdS required for device grade solar cell is in the range of 50-60 nm. Tlie thickness is dependent on the deposition time, deposition temperature, concentration of the cadmium and sulphur source, and pH. A study of the effect of each on the parameters on the thickness, transmittance and hand gap will help in tuning the thickness, transmittance and band gap. So in this work we have found the relation for the thickness for each of the variable parameters.

9 illus, 13 ref

022883   Choudhury D;Katdare A D;Shukla S K;Munwar Basha B;Ghosh P (Civil Engineering Dep, Indian Institute of Technology Bombay (IIT Bombay), Powai, Mumbai-400 076) : Seismic behaviour of retaining structures, design issues and requalification techniques. Indian Geotech J 2014, 44(2), 167-82.

Realistic estimation of seismic earth pressure is very crucial for the design of retaining structures in seismic-prone areas. Several researchers have developed analytical and numerical methods for the estimation of seismic earth pressure. Some experimental studies are also reported to clearly present the seismic behaviour of retaining structures. Pseudo-static and pseudo-dynamic methods are the ones which are popularly used for the calculation of seismic earth pressure. Pseudo-dynamic method is a modification of the conventional pseudo-static method by eliminating most of the limitations. Recently, the researchers have shown that the new dynamic method considering Rayleigh wave, which plays a major role in the calculation of seismic earth pressures to maintain compatible dynamic stress boundary conditions, is better than pseudo-dynamic method as validated through the available dynamic centrifuge test results. This state-of-the-art paper presents a critical review of the literature on the available procedures for the seismic analysis, design and requalification of retaining structures. The methods which are currently used in routine practice for the seismic design of retaining structures are also explained briefly. Indian and some other international design codes for the seismic design of retaining - 272 - structures are explained. For new design and requalification of existing retaining structures in seismic-prone areas, a worked out example is provided with recommendations for techniques of requalification.

81 ref

022882   Choudhary S;Sengwa R J (Dielectric Research Laboratory, Physics Dep, J N V Univ, Jodhpur-342 005, Email: rjsengwa@rediffmail.com) : Dielectric relaxation and lithium ion transport study of ultrasonic and microwave irradiated polymer nanocomposite electrolytes. Indian J Engng Mater Sci 2014, 21(1), 7-15.

Polymer nanocomposite electrolytes (PNCEs) consisted of poly(ethylene oxide) (PEO) and lithium perchlorate (LiClO₄) (stoichiometric ratio EO:Li⁺ = 8:1) with montmorillonite (MMT) clay as inorganic nanofiller are prepared through ultrasonicated and microwave irradiated electrolyte solutions by a solution casting method following the melt-press technique. The electrical characterizations of these PNCE films are carried out using dielectric relaxation spectroscopy in the frequency range from 20 Hz - 1 MHz at ambient temperature. The real part of complex permittivity of these electrolytes has dispersion over the frequency range 1-100 kHz where the polymer segmental dynamics relaxation peak is appeared in the dielectric loss spectra. The values of dielectric strength and relaxation times for these electrolytes are determined, and a correlation of these parameters with the dc ionic conductivity is explored. The results reveal that the lithium cations are coordinated with exfoliated MMT nanosheets and functional group of PEO, which make a transient cross-linked structure in these materials. The presence of MMT in the polymer electrolyte matrix offers hindrance to the cations mobility which is reflected from decrease in ionic conductivity of PNCE films. The X-ray diffraction patterns confirm an amorphous nature of the electrolytes with the exfoliated MMT structures.

8 illus, 1 table, 48 ref

022881   Choudhary I;Mathur A;Halder S (Mechanical Engineering Dep, National Institute of Technology Silchar, Assam, Email: ikbal.choudhary.nits@gmail.com) : Determination of elastic behaviour of self-healing composites. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1), 20-4.

Present work consists of studies related to self-healing composites having encapsulated healing agent. Several research works have been conducted to prepare self-healing systems and for the identification of their mechanical properties. However, limited work has been done to evaluate elastic behavior of self-healing composites using different mathematical models. In this article we have used some well-known mathematical models to calculate - 271 - elastic modulus of the capsules in particular and the overall composite. The experimental results from relevant research works are correlated with our theoretical predictions and some suitable analogy is drawn.

3 illus, 20 ref

022880   Chopra K N (Applied Physics Dep, Maharaja Agrasen Institute of Technology, Rohini GGSIP Univ, New Delhi-110 086, Email: kchopra2003@gmail.com) : Short note on the hydro power and optimization of the power output of the hydro turbines. Invertis J renewable Energy 2013, 3(2), 125-32.

The field of hydro power is expanding at a very brisk pace, and newer ideas and applications are being suggested by the designers and researchers in this field. A short review note on the concepts and applications of the technology has been presented. The Hydrostatic Dam Installation, Turbine Installation in River, and Tidal Power have been briefly discussed. The power output analysis and the design aspects of the various types of turbines along with their suitability for the particular cases have been reviewed, with a view to optimize the power output, The challenges in the application of the wave power and the.ocean thermal energy have been outlined. It is expected that this short review will be useful for the design engineers and the researchers entering the field.

2 illus, 29 ref

022879   Chokshi N P;Shah K P;Gangdev B P (Chemical Engineering Dep, Nirma Univ, Ahmedabad, Gujarat, Email: nikita.chokshi@nirmauni.ac.in) : Shale gas-future scope & challenges. Int J latest Technol Engng Mgmt appl Sci 2014, 3(1), 107-11.

Coal is the major fuel for India today. But with the depleting coal reserves and the increasing demands of fuel, we need an alternative. Shale gas (a form of natural gas available in shale rocks) is the most promising alternative. Shale gas is considered to create less harm to environment, as compared to coal. The exploration techniques include hydraulic fracturing and horizontal drilling. But these techniques have certain drawbacks related to land and water resources. There are companies which have found an alternative technique-Waterless fracturing. The liquid propane gas fracturing among the various techniques is found to be more viable. The exploration techniques are found to be cheaper than coal mining in the long run. Also it can reduce our energy import bills.

4 illus, 8 ref

022878   Chen Z Y;Li W Y;Yang L D (Geotechnical Engineering Dep, Tongji Univ, Shanghai-200 092, China) : Simplified seismic design method for Shanghai underground structures in soft soils. Indian Geotech J 2014, 44(2), 149-5.

This paper presents a simplified seismic design method, the equivalent horizontal seismic inertial force method (EHSIFM), for underground structures in soft soils, especially for application in Shanghai subway structures. The EHSIFM utilizes the quasi-static approach. In this approach, the effects of equivalent horizontal seismic inertial forces, representing the dynamic forces induced by an earthquake, are imposed on the underground structures. Several - 270 - parameters are derived through numerical correlation using values of embedded depth and soil types typical to Shanghai. The principle of equivalent limit state is adopted, in which the maximum internal force as well as its position on the underground structure under inertial forces, is identical to the real value. A sample design on a modeled double-story three-span subway station in soft soils is also conducted. Analytical results show that the EHSIFM is simple yet accurate enough to reflect structural seismic responses in an earthquake.

12 ref