016202   Medesety P (NO, , ) : Wall to bed mass transfer in the presence of double cone promoter in a three phase fluidized bed with conical entry of electrolyte. J Petrol Engng Technol 2017, 7(2), 39-43.

Investigations have been carried out experimentally to study the effect on wall-to-bcd mass transfer coefficient in presence of double cone promoter in a three-phase fluidized bed with a conical entry of electrolyte. The system chosen was an electrolyte as liquid phase, glass spheres of different diameters as solid phase and inert nitrogen as gas phase. - 287 - The electrolyte was an equimolar solution of potassium ferricyanide and potassium ferrocyanide each of 0.01 N with 0.5N sodium hydroxide as indifferent electrolyte. The reaction considered was the reduction of ferricyanide ion. The experiment had been carried out at temperature range of 36 to 38°C at which the physical property values of the electrolyle were known from literature. The mass transfer coefficient was computed from the measured limiting current. It was found that the mass transfer coefficient was relatively independent of liquid velocity within the range covered in the present experiment. The k_L increased marginally with increasing gas velocity. The k_L was not influenced significantly by particle size and diameter of promoter within the present study range. The entire experimental data have been correlated in terms of Coulburn j_D-factor and particle Renolds numbers.

016201   Maiti D K;Sreehari V M (Aerospace Engineering Dep, Indian Institute of Technology Kharagpur, WB 721302, Email: dkmaiti@aero.iitkgp.ernet.in) : Bending and buckling analysis of composite laminates with and without presence of damage and its passive control with optimized piezoelectric patch location. Proc Indian Natn Sci Acad 2016, 82(2), 329-40.

This work presents an efficient technique to enhance the bending and buckling characteristics of a smart composite plate. This paper discusses about the employment of piezoelectric fibre composite patches (PFCP) in their optimized location using unified particle swarm optimization (UPSO) for enhancing the performance and thereby reducing the effects of internal flaws. A finite element formulation based on Inverse Hyperbolic Shear Deformation Theory (IHSDT) for handling bending and buckling analysis of a smart composite plate is used in the present work. In addition to the best performance, reduction in weight of piezoelectric material is obtained as we employ a segmented piezo patch to overcome the degradation in buckling strength due to damage in a composite plate, which indeed addresses the design issues.

15 illus, 3 tables, 45 ref

016200   Liu X;Zhang Z;Hu W;Le Q;Bao L;Lu K (School of Metallurgical and Ecological Engineering, Univ of Science and Technology Beijing, Bejing 100083, People's Republic of China, Email: qichil@mail.neu.edu.cn) : Grain refining mechanism of ZnO particles on magnesium alloys. Indian J Engng Mater Sci 2016, 23(6), 383-8.

Grain refining of ZnO particles on magnesium alloys has been investigated by suction casting. Based on the experimental and thermodynamic data available, ZnO particles would be converted into the solute Zn in Mg melt. However, the ZnO particles have a slightly stronger grain refining potency than Zn. The grain refining efficiency of ZnO particles is mainly attributed to the restricting effect of Zn solute and in situ produced MgO particles as potent nuclei. Meantime, the large amount of reaction heat may cause intensive micro convection and mass transfer to eliminate the solute accumulation between existed grains, which could improve the nucleation rate.

8 illus, 1 table, 23 ref

016199   Kumar S;Singh G;Mohapatra S K (Mechanical Engineering Dep, Thapar Univ, Patiala-147 004, Email: satish.kumar@thapar.edu) : Leaching characteristics of heavy metal in bottom ash from indian thermal power plant. J scient ind Res 2017, 76(4), 255-8.

The disposal of bottom ash in the thermal power plant is a challenging task. The objective of the present study was to investigate the leaching - 286 - characteristics of the bottom ash disposed in ash pond of thermal power plants. The studies were conducted with bottom ashes from ash disposal system. A series of leaching test have been performed with different liquid to solid ratio (L/S). The (L/S) varies from 20:1 to 60:1. It is observed that the elements of Mn, Mg, Cr, Zn, Ni, and Cu are most abundant elements while Pb, Mo, Fe and Co are the least abundant elements. It is also observed that the leaching characteristics of the bottom ash are affected by the pH of extraction solution and liquid to solid (L/S) ratio.

2 illus, 1 table, 15 ref

016198   Kheyroddin A;Beiraghi H (Civil Engineering Faculty, Semnan Univ, Semnan, Iran, Email: H_beiraghi@yahoo.com) : Wind induced responce of half-storey outrigger brace system in tall buildings. Curr Sci 2017, 112(4), 855-61.

In all previous studies, the outrigger arms are symmetric with respect to the centre line of the core. Hence, each outrigger involves two arms at the same level which usually occupy one, two or three stories. In this communication, the innovative idea is to implement the outrigger arms asymmetrically. One main purpose of this study was to investigate the feasibility study of four half-storey outriggers system instead of the corresponding two-storey outrigger system. To study the effects of the newly defined configurations on the global performance of tall buildings, some 30-, 45- and 60-storey two-dimensional steel frames with braced core systems at centre have been analysed and designed under gravity and wind load without outriggers. Later, the outrigger trusses were added in different arrangements at the optimum locations. The results show that the new idea will improve the system efficiency.

6 illus, 5 table, 13 ref

016197   Karthikeyan S;Prathima A (Mechanical Engineering Dep, Syed Ammal Engneering College, Ramanathapuram-623 502, Email: skarthikeya74@gmail.com) : Experimental investigation lof marine engine heat transfer and pressure drop in in mini channel. Indian J Geomar Sci 2017, 46(2), 371-6.

In this project the DI water is used as the working fluid in the three varying shape of the mini channel to investigate the heat transfer and the pressure drop. Various mini channels are straight mini channel, wavy mini channel and combined straight and wavy mini channel. In this project we compare the heat transfer and pressure drop of the three various mini channel, and the result obtained is wavy channel provides better than the other two channels.

10 illus, 1 table, 10 ref

016196   Karihaloo B L; (School of Engineering, Cardiff Univ, Cardiff, CF24 3AA, UK, Email: karihaloob@cardiff.ac.uk) : St venant torsion and bending of prismatic composite shafts. Proc Indian Natn Sci Acad 2016, 82(2), 183-200.

This paper discusses the use of high-performance incompatible, enhanced-strain and hybrid stress elements for the St Venant torsion and bending of composite prismatic shafts, formulated in terms of the warping function. The properties of the shaft are uniform along its length but piece-wise constant and orthotropic across its cross-section. In order to analyse composite shafts whose microstructural details are difficult to be modelled directly by finite element discretisation, the two-scale asymptotic (or mathematical) homogenisation approach is also discussed; the resulting equilibrium equations can be readily solved by the aforementioned high-performance elements.

7 illus, 4 tables, 30 ref

016195   Kamel A H;Harouaka A H (NO, , ) : Rheology amd flow properties of fracturing gels in straight and coiled tubing. J Petrol Engng Technol 2017, 7(1), 27-43.

This study involves experimental investigation of rheological and hydraulic characteristics of aqueous based polymeric and surfactant fluids in straight and coiled tubing. The fluids matrix includes guar, HPG, PHPA, welan, xanthan, and surfactant. Bohlin rheometer was used to evaluate rheological and viscoelastic characteristics. For hydraulic characteristics small- and large-scale flow loops were used. It is observed that all fluids exhibit comparable non-Newtonian behavior and improved viscous and elastic properties. Among polymeric fluids guar and welan provide better viscosity and suspension properties. Surfactant is significantly affected by the formation of rod-like micelles and other microstructures. Master curves for rheological and elastic properties are developed using the molecular theory approach. The foremost benefit of these curves is its dimensionless form that provides a unique technique to predict viscosity for all fluids. For hydraulic properties, friction losses in coiled tubing arc significantly higher than in straight tubing due to centrifugal forces and secondary flows Surfactant is more sensitive to shear field applied where different microstructures are induced and thus they exhibit better drag reduction characteristics than polymeric fluids especially in coiled tubing with larger sizes. However, in straight tubing, guar shows better drag reduction characteristics than surfactant and other polymers, which diminishes as tubing size increases However welan gum exhibits a comparable performance. Overall, all fluids are considered good candidates as fracturing fluids with specific features for each. Unique characteristics of each fluid is discussed and explained in more details within the context of the present paper.

016194   Kalpana G;Rajendran V (NO, Sathyabama Univ, Chennai-600 119, Email: kalpana27783@gmail.com) : Comparative study on the improvement of SNR using wavelet techniques for a linear FM acoustic signal. Indian J Geomar Sci 2017, 46(2), 358-64.

The study is to develop denoising algorithm using wavelet decomposition technique by incorporating the most matchable Gabor wavelet. Performance the denoising technique is assessed by improving the signal to noise ratio and comparing the performance of Gabor wavelet with various other wavelets like Haar, Bior and Symlet wavelets. Ocean background noise is not the same at all time and at all regions. It is very distinct and location specific. Hence the noise prevailed in the region of bay of Bengal, Chennai was collected using the broad band hydrophone, for this study and the simulation was carried out using Mat lab Simulink tool. The results proved that the Gabor wavelet has given a good SNR improvement when associated with other wavelets for this particular work.

8 illus, 3 tables, 14 ref

016193   Kalaiselvan K;Elango A;Nagarajan N M (Mechanical Engineering Dep, Meenakshi Ramasamy Engineering College, Ariyalur-621 804, Email: kalaiesanai@gmail.com) : Microstructure and EDS analysis on titanium/aluminium dissimilar laser welded joint subjected to age hardening. Indian J Engng Mater Sci 2016, 23(6), 377-82.

Laser beam welding of titanium and aluminium alloy is very much needed for aerospace and automotive industries due to its high strength and light weight. The dissimilar welding is having a bearing on high temperature at the weldment and grain coarsening may cause if thermal cycle is not checked. In order to maintain good weld joint properties, phase transformation during rapid thermal cycles is required. Such cycles occur during welding of titanium/aluminium dissimilar sheets and age hardening heat treatment after welding. Titanium and aluminium alloys are sensitive to heat - 284 - due to their difference in melting temperatures. This may cause changes in microstructures in weldment. The aim of this study is to analyse the changes in titanium (TI6AL4V) and aluminium (AA2024) alloy thin sheets welded joint using SEM and EDS studies before and after age hardening heat treatment. From the results, it is observed that laser beam focusing from titanium side gives well refined age hardened structure and EDS reveals that the bond is metallurgical one.

11 illus, 3 tables, 21 ref

016192   Iyer N R;Palani G S;Murthy A R (NO, , Academy of Scientific and Innovative Research (AcSIR) and Former Director, CSIR-Structural Engineering Research Centre (, Email: nageshiyer@acsir.res.in) : Advanced methodologies for fracture analysis and damage tolerant evaluation. Proc Indian Natn Sci Acad 2016, 82(2), 209-22.

The objective of the paper is to present the advanced methodologies for fracture analysis and damage tolerant evaluation of metallic structural components for efficient and safe design of structural systems meeting the functional criteria. An efficient and novel Numerically Integrated-Modified Virtual Crack Closure Integral (NI-MVCCI) technique has been demonstrated for 4-noded bilinear, 8-noded (regular & quarter-point), 9-noded Lagrangian and 12-noded cubic isoparametric family of finite elements. Another advanced numerical method, Extended Finite Element Method (XFEM) for fracture analysis of cracked stiffened panels has been discussed. Methodologies for crack growth and remaining life assessment of structural components under constant and variable amplitude loading have been presented. Brief description on residual strength evaluation has been provided. Numerical studies on fracture analysis to compute Strain Energy Release Rate (SERR), G and stress intensity factor (SIF) and remaining life assessment and residual strength evaluation have been conducted and the results are compared with the respective analytical/experimental results.

13 illus, 29 ref

016191   Isik M F;Haboglu M R;Yanmaz H (Electric and Electronics Engineering Dep, Hitit Univ, Corum, Turkey, Email: mehmetfatih@hitit.edu.tr) : Design and implementation of a closed loop electronic driver circuit for the air curtains used in aspirators. J scient ind Res 2017, 76(4), 229-34.

Although their low efficiency values, permanent split capacitor (PSC) motors are preferred especially for the aspirators used in household applications for their low cost and high durability. Those motors are the main components that provide the - 283 - working of the air curtains. One of the most important characteristics of air curtains is that they work discretely with work levels. As the level is increased, noise level also increases along with energy consumption and heat. That undesired situation causes efficiency problems for energy consumption. Additionally, high noise values are disturbing for the house residents. The speed of the conventional PSC motors are adjusted in stages which allows to set only discrete speed values. In this study, a new electronic driver circuit that eliminates the discrete speed adjustment and allows to set a speed value in the interval of the PSC stages is designed for the devices that provide the air flow in aspirators. An automatic feedback system is developed in order to control the motor speed. For that feedback mechanism, a novel air flow sensor is designed. In addition, a fault detection and warning system is developed for possible errors. As a result of the experiments, the developed driver circuit and feedback system shows less heat and noise values along with higher energy efficiency.

3 illus, 3 tables, 37 ref

016190   Ibeh S U;Obah B (NO, , ) : Challenges and prospects of the use of horizontal directional drilling techniques for laying oil and gas pipelines in Nigeria. J Petrol Engng Technol 2017, 7(2), 9-20.

Nigeria pipelines, especially the petroleum and petroleum product pipelines are always vandalized by the sabotage. Huge amount of money is expended to put the damaged pipeline in good shape; and petroleum and petroleum product transfer is sometimes hampered due to leakages and damages caused by the oil thieves. Also huge money is being budgeted yearly to secure the pipelines. To combat this problem, horizontal directional drilling (HDD) is being proposed. HDD is a method of installing underground pipes and conduits along a prescribed bore path from the surface, with minimal impact to the surrounding area. Installation lengths up to 6500 ft and depth of 200 ft have been completed and diameters up to 48 in have been installed in shorter runs. The process begins when a directional bore machine pushes a bore head connected to hollow pipe info the ground at an angle. As each joint of drill pipe is pushed into the ground, a new one is added behind. In rock, a mud motor, which converts the hydraulic pressure of the drilling fluid into mechanical rotation, is used to rotate the bit and the drill pipe is not continuously rotated. Steerage is accomplished by aligning the angle of the mud motor to the desired direction. This paper investigates the challenges and prospects of using the HDD technique to lay pipeline to a greater depth/distance that will be inaccessible to the oil thieves. The construction process (pilot hole, reaming and pullback) along with the major components (drill rig, drill pipe, slurry, slurry recycling, survey equipment, drill bits, and reamers) is discussed. The. advantages of cost reduction, and environmental, social and time benefits were examined in this study. The challenges of proper soils information, subsurface conditions, training and knowledge, drilling fluids and binding of the drill pipe and reamer/bit are highlighted.

016189   Hasan H M;Nithiarasu P (Biomedical Engineering and Rheology Group, Zienkiewicz Centre for Computational Engineering, Swansea Univ, Swansea SA2 8PP, United-Kingdom, Email: P.Nithiarasu@swansea.ac.uk) : Robust finite element approaches to - 282 - systemic circulation using the locally conservative galrekin (LGC) method. Proc Indian Natn Sci Acad 2016, 82(2), 163-72.

In this paper novel finite element algorithms for robustly solving flow equations of a systemic circulation are presented and compared. A novel, Locally Conservative Galerkin (LCG) method is developed by adopting semi- and fully-implicit time discretisations to address the behavior of blood flow in the human circulatory system. These techniques are efficient for nonlinear system of equations used in blood flow models and achieve rapid convergence. Several comparisons are made between the methods to demonstrate the validity and stability of the current numerical models to solve the blood flow characteristics in a human body.

9 illus, 1 table, 28 ref

016188   Haque A K M R;Mannan M A;Tamura J (NO, , ) : Power control of doubly fed induction generator (DFIG) based on ip controller. J Pwr Elect Pwr Syst 2016, 6(3), 23-32.

Conventionally, the indirect power control of Doubly Fed Induction Generator (DFIG) has been developed based on conventional Proportional-Plus-Integral (PI) controller due to its simple construction and implementation. The steady-state error minimization, overshoot elimination and disturbance rejection are not possible where the gains of PI controller are chosen by trial and error method. The steady-state error and disturbance rejection can be possible if the gains of PI controller are chosen by proper choosing of poles. But the overshoot elimination is not possible where PI based control is designed. In this paper, Integral-Plus-Proportional (IP) controller is proposed to design for power control of the DFIG. The IP controller is well suited to minimised the overshoot problem which is arisen in PI controller. The performance of proposed IP controller for power control of the DFIG system is analyzed and investigated through the simulation work. The results of simulation works are presented to demonstrate the effectiveness of propose IP controller compared with conventional PI controller. The proposed IP controller shows the superior performance over PI controller in terms of minimization of overshoot.

016187   Gupta V;Ghoniem N M;Crum R;Po G;Seif D; Prikhodko S V;Colorado H A;Ramirez B;Gamez C (NO, , Materials Science and Engineering Dep, UCLA, Email: vgupta@ulca.edu) : Microstructure evolution in metal nanostructures under extreme conditions of temperature and strain rate. Proc Indian Natn Sci Acad 2016, 82(2), 201-8.

This paper explores a fundamental connection between ductility and domain size in metallic solids under extreme conditions of cryogenic temperatures and strain rates (10⁸s^-1). A series of novel experiments, backed by multiscale modelling and transmission electron microscopy (TEM) analysis, are presented that involve loading of TEM-ready single crystal nano-pillar samples of Cu of varying lengths (50 nm to 1 mm) and aspect ratios (50 nm to 100 nm in diameter) by laser-generated stress waves of sub-nanosecond rise times, under extreme conditions of strain rate (<62>10⁸s^-1) and temperature (100K). The nucleation stress for Shockley partials, which can be taken as a proxy for the onset of ductile deformation, was measured to be only 1 GPa. This is an order of magnitude lower than the previously measured values of 35 GPain bulk geometries. TEM observations show remarkable ability of the material to re-arrange itself through motion of dislocations to form subgrain boundaries within a very short duration of only few nanoseconds.

9 illus, 8 ref

016186   Gupta S K;Malik M;Gupta D (NO, , ) : Application of accelerated PSO and ANN for optimal scheduling of hydrothermal system. J Pwr Elect Pwr Syst 2016, 6(3), 45-52.

A short range problem of hydro thermal scheduling of hydrothermal system with cascaded is analyzed in this paper. The net head, water discharge rate and water transport delay between connected reservoirs is considered in the problem. The developed algorithm is demonstrated on a test system consisting one thermal plant and four cascaded hydro plants. The results obtained by the APSO technique are compared to PSO and conventional technique. It - 281 - is found that result obtained by APSO approach is superior in term of fuel cost and lesser computational time. The results of PSO, APSO and conventional technique are faking as inputs for the training to ANN system. ANN provides better result as comparison of PSO, APSO and conventional technique.

016185   Grandhi R V (NO, Wright State Univ, 3640 Colonel Glenn Hwy., Dayton, OH 45435 USA, Email: ramana.grandhi@eright.edu ) : Multi-fidelity design optimization: Challenges in complex physics-based computational mechanics. Proc Indian Natn Sci Acad 2016, 82(2), 369-83.

Engineering systems development is currently pushing the envelope of traditional multidisciplinary design capabilities. Bringing multiple physics into the design loop earlier in the design process has shown promise in handling the strict requirements constantly being placed on various areas of computational mechanics, such as the design of next generation military aircraft. The goal in multi-fidelity design is to aid in this process to expand traditional design capabilities through the implementation of techniques developed to mitigate inadequacies and/or obstacles associated with various levels of complex physics in a single design process. Achieving a desired level of accuracy while maintaining a low computational cost may very well be the greatest obstacle combating computational design. However, other hindrances exist such as determining the appropriate physics (i.e. acoustic, thermal, structural), level of physics (i.e. Potential Flow, Euler, Navier Stokes), and mesh refinement to utilize in any given computational model. This work focuses on leveraging higher fidelity information to correct lower fidelity models so as to take advantage of the speed associated with the latter without compromising accuracy. Corrections are implemented via a custom Hybrid Bridge Function (HBF) while the design aspect is governed through the implementation of a special Trust Region Model Management (TRMM) methodology. Multi-fidelity design optimization is demonstrated on a thermal plate demonstration problem consisting of four differing levels of fidelity. Results show that employment of the described methodology succeeds in obtaining a design at a lower cost while maintaining a necessary level of accuracy.

3 illus, 1 table, 27 ref

016184   Ganguli R (Aerospace Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: ganguli@aero.iisc.ernet.in) : Physics based finite element - 280 - interpolation functions for rotating beams. Proc Indian Natn Sci Acad 2016, 82(2), 257-70.

Rotating beams are ubiquitous members of industrial structures such as wing turbine rotors, helicopter rotors, turbomachinery, robotic systems and aerial robots. Typically, finite element analysis is used to solve the vibration problem for these structures. We show that it is possible to significantly enhance the efficiency of the finite element methods for rotating beams by creating basis functions which more closely satisfy the governing differential equation of the structure. Since the rotating beam equation cannot be solved as an exact solution, different approximate strategies are explored to improve finite element convergence, especially at higher rotating speeds where the centrifugal stiffening terms become dominant.

21 illus, 3 tables, 23 ref

016183   Elayaraja D;Ramabalan S (Mechanical Engineering Dep, K Ramakrishnan, College of Engineering, Trichy-621 112, Email: dekrce@gmail.com) : Investigation in autonomous line follower robot. J scient ind Res 2017, 76(4), 212-16.

The line follower robot is a mobile machine that can detect and follow a line drawn on the floor. In this paper, a predefined path is provided and the path is made up of a black line on a white surface with high contrast color. The mobile robot senses the path with two of its infrared sensors that installed under the robot and a third infrared sensor is used for obstacle avoidance. The left sensor controls the right wheel and the right sensor control the left wheel. The sensors detect the path and provide the information to the microprocessor. The microprocessor activates the motors depending on the path which may be straight or curved. The robot is allowed to follow a line of 4m length with varying wheel diameter and Castor position. The times taken for the travel under different arrangement were tabulated. Design of Experiments is used for finding optimal design parameters of the robot for time taken to complete the travel along the predefined path. The parameters considered are Wheel Diameter 'D' for three levels (70 mm, 80 mm, 90 mm), Centre to Centre (C-C Distance) between the Caster wheel centre and the Rear wheel centre for three levels (90 mm, 100 mm, 112 mm). Finally empirical model have been formulated by the application of Regression Modeling after evaluation of Test of hypothesis for above mentioned levels and factors for significant effects. The results obtained from the design of experiments are given fed in to the fuzzy logic controller. The results of the two methods were compared and obtained satisfactory results.

3 illus, 3 tables, 12 ref

016182   Duryodhan V S;Singh A;Singh S G;Agrawal A (NO, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Email: aagrawal.iitb@gmail.com) : Three-dimensional numerical study of - 279 - conjugate heat transfer in diverging microchannel. Proc Indian Natn Sci Acad 2016, 82(2), 321-8.

Increase in applications of varying cross sectional area microchannels in microdevices has provided the need to understand fluid flow and heat transfer through such flow passages. This study focuses on conjugate heat transfer study through a diverging microchannel. Three-dimensional numerical simulations are performed using commercially available package. Diverging microchannels with different geometrical configurations (i.e. varying angle: 1-8°, depth: 86-200 μm, solid-to-fluid thickness ratio: 1.5-4) are employed for this purpose. Simulations are carried out for varying mass flow rate (3.3 x 10^-5-8.3 x 10^-5 kg/s) and heat flux (2.4-9.6 W/cm²) conditions. Heat distribution along the flow direction is studied to understand the effect of wall conduction. Wall conduction number (M) varies from 0.006 to 0.024 for the range of parameters selected in the study. Wall conduction is observed to be a direct function of depth and solid-to-fluid thickness ratio, and varies inversely with angle of diverging microchannel. It is observed that the area variation and wall conduction contribute separately towards redistribution of the supplied heat flux. This leads to reduced temperature gradients in diverging microchannel. The results presented in this work will be useful for designing future microdevices involving heating or cooling.

8 illus, 2 tables, 14 ref

016181   Dumont N A;Peixoto H D F C (Civil Engineering Dep, Pontifical Catholic Univ of Rio de Janeiro, Brazil, Email: dumont@puc-rio.br) : Fast-multipole unified technique for the analysis of potential problems with the boundary element methods. Proc Indian Natn Sci Acad 2016, 82(2), 289-99.

The proposed developments are based on a consistent implementation of the conventional, collocation boundary element method (BEM). A scheme is used to expand a generic (not problem-dependent) fundamental solution about hierarchical levels of source and field poles, which is particularly advantageous to make the technique seamlessly applicable to 2D and 3D problems of elasticity or potential, in terms of different types of curved elements for generally complicated geometry and topology. The proposed compact algorithm is more straightforward to lay out and seems to be more efficient than the ones available in the technical literature - particularly because the outermost loop refers to field nodes and geometry, in what may be called a reverse implementation. Some numerical results are shown for the conventional BEM, with validation and assessment for a few simple, but very large-scale, 2D potential problems with complicated geometry and topology for constant, linear and quadratic elements. Since iterative solvers are not required in this first step of numerical simulations, an isolated assessment of accuracy, computational effort and storage allocation of the proposed fast multipole technique becomes possible.

16 illus, 16 ref

016180   Dhanesh N;Kapuria S (Applied Mechanics Dep, Indian Institute of Technology Delhi, New Delhi-110 016, Email: kapuria@am.iitd.ac.in) : Free edge effects in sandwich laminates under tension, bending and twisting loads. Proc Indian Natn Sci Acad 2016, 82(2), 233-45.

An accurate analytical solution for predicting the free edge effects in sandwich laminates under tension, bending and twisting loading is presented. The recently developed mixed-field multiterm extended Kantorovich method (MMEKM) has been used to obtain the solution of the governing equations, which are developed using the Reissner-type variational principle. The present mixed-field approach enables the exact and point-wise satisfaction of traction-free edge and interlaminar continuity conditions for displacements and stresses. The numerical results presented for different loadings and lay-up show rapid convergence of the iterative series solution. The comparison of the present results with the detailed FE solution shows good agreement. The present solution captures the singularity of stresses in the free edge region by showing the rise in its peak magnitude with the number of terms in the solution. The presented accurate 3D elasticity based solution can act as a useful benchmark for assessing the accuracy of solutions obtained from other approximate methods.

11 illus, 1 table, 27 ref

016179   Devarajaiah R M;Suresha B (Mechanical Engineering Dep, Acharya Institute of Technology, Bengaluru-560 107, Email: sureshab2004@yahoo.co.in) : Role of organo-modified montmorillonite nanoparticles on wet sand abrasion of carbon fabric reinforced epoxy composites. Indian J Engng Mater Sci 2016, 23(6), 411-7.

The effect of nano-clay (oganomodified montmorillonite, oMMT) on wet sand/rubber wheel abrasive behaviour of carbon fabric reinforced epoxy (C-E) composites was investigated in this study. The C-E composite with different oMMT loadings (0, 1.5, 3 and 5 wt %) were fabricated by hand layup technique followed by autoclave curing. Three-body abrasive tests were carried out at two different normal loads by varying the abrading distance from 270 m to 1080 m. The experimental results showed that the wear volume increases with increasing applied normal load and abrading distance. The specific wear rate was found to increase with the increase in applied load and decreases with increasing abrading distance. Both the wear volume as well as specific wear rate were found to decrease - 278 - with increase in oMMT loading. The carbon fabric reinforced epoxy with 5 wt % oMMT loading displayed superior abrasion resistance when compared to other composites. Worn surface morphology was carried out to understand the involved wear mechanisms.

8 illus, 2 tables, 27 ref

016178   Chowdhury S R;Roy D (Mechanics Lab Dep, Indian Institute of Science, Bangalore-560 012, Email: royd@civil.iisc.ernet.in) : Two-temperature continuum model for metal plasticity. Proc Indian Natn Sci Acad 2016, 82(2), 247-55.

A physically based continuum plasticity model for metals from the consideration of non-equilibrium thermodynamics is presented. The modeling is accomplished in a two-temperature framework that appears naturally by considering the thermodynamic system to be composed of two weakly interacting subsystems, namely the kinetic vibrational and configurational subsystems. While the atomic vibrations of plastically deforming metals form the kinetic vibrational subsystem, much slower degrees of freedom in terms of the motion of defects constitute the configurational subsystem. Both subsystems assume their own temperatures and fall out of equilibrium from each other because of the externally imposed driving. Dislocation density characterising the configurational subsystem is considered to be the state variable for the present development. The continuum model accommodates finite deformation and describes plastic deformation in a yield-free framework via a microforce balance along with the conventional macroforce balance.

9 ref

016177   Chandrasekaran M;George J;Arunachalam R M; Teyi N (Mechanical Engineering Dep, NERIST, Arunachal Pradesh, Email: mchse1@yahoo.com) : Multi-objective parametric optimization for non-conventional machining of inconel 825 - for an industrial application. J scient ind Res 2017, 76(5), 314-9.

Inconel and titanium based alloys are hard, high temperature resistant and high strength materials finding wide application in aerospace, marine, food processing and nuclear industries. The conventional machining of these materials results in higher cutting forces and excessive tool wear. Wire cut electrical - 277 - discharge machining (WEDM) being one of the popular non-conventional machining processes is used for macro and micro machining of hard and high strength materials. In this work, an experimental analysis and response surface modelling of WEDM process of Inconel 825 has been carried out. The surface roughness (Ra) and material removal rate (MRR) are two common performance parameters for accessing the ability of WEDM process. Pulse on time (T_on), pulse off time (T_off), peak current (I_p) and servo voltage (SV) are used as process parameters. Response surface methodology (RSM) modelling between inputs-output relationships has been obtained. The developed full quadratic model with R² value of 92.06% and 95.62% for R_a and MRR respectively, produces less percentage error. The relationship between process responses and input factors are analyzed with 3D surface plots. The multi-objective optimization of non-conventional machining of Inconel 825 using genetic algorithm (GA) provides 21 Pareto-optimal fronts. An optimization table is generated for use in manufacturing industry for the production of components of desired surface roughness with maximum MRR.

3 illus, 1 table, 11 ref

016176   Cangir B;Dipova N (Civil Engineering Dep, Akdeniz Univ, Dumlupinar Bulvari, 07058 Kampus, Antalya, Turkey, Email: ndipova@akdeniz.edu.tr) : Estimation of undrained shear strength of konyaalti silty clays. Indian J Geomar Sci 2017, 46(3), 513-20.

In this research, the shear strength of the blue-green soft silty-clays in Konyaalti (Antalya) has been investigated. Samples taken in every 0.5 m from boreholes were investigated using laboratory methods. Additionally, CPT and SPT tests were conducted near the boreholes. Some important correlations have been established between undrained shear strength (S_u), physical soil properties and in-situ test results, in order to develop predictive models. As a result of statistical analysis of correlations between undrained shear strength-overconsolidation ratio and dry unit weight, high correlation coefficients were obtained. Besides the laboratory tests, Standard Penetration and Cone Penetration tests results were correlated with undrained-unconsolidated triaxial test results to predict (S_u). Finally, an empirical model to predict S_u were developed.

8 illus, 46 ref

016175   Buchacz A;Galeziowski D (Institute of Engineering Processes Automation and Integrated Manufactu, Silesian Univ of Technology, Konarskiego 18a Street, 44-100 Gliwice, Poland) : Parameters identification and selection in various mechatronic vibrating structures. Indian J Engng Mater Sci 2016, 23(6), 425-30.

In this paper, the detailed constrains related with designing of the mechatronic discrete vibrating systems has been examined. The design process is considered as a synthesis that has been done with regard to defined requirements in form of the poles and zeros. The main focus of the paper is given to the optimization and verification of selection of the major parameters, orientated for physical realization and widening the possible applications. Parameters of the presented systems have been divided and detailed for the ones that describe the piezoelectric actuator, known ones related to synthesis, and the ones that comes from dimensionless transformation and retransformation algorithm. The study has been performed based on various configurations of example cascade mechatronic system with one degree of freedom that contains piezo stack actuator connected to external electric circuit LRC, and has been directed for the best vibration isolation effectiveness.

9 illus, 1 table, 10 ref

016174   Bogdan I;Corneliu M;Carmen-Iulia C;Iacob S S; Marcelin B;Kamel E (Faculty of Mechanical Engineering, "Gheorghe Asachi" Technical Univ of Iasi, 43 "D. Mangeron" Street, 700050, Iasi, Romania, Email: cornelmun@gmail.com) : Morphological and tribological aspects of some ZrO₂ coatings on Mg-Ca biodegradable alloys. Indian J Engng Mater Sci 2016, 23(6), 418-24.

The Mg-Ca biodegradable alloy system has been proposed as a potential new kind of degradable biomaterial with possible application within medical and orthopedic field. These alloys are biocompatible with human organism being abase component for many enzymes. Magnesium based alloys releases biodegradable corrosion products during degradation process and are suitable for tissue regeneration in the human body. For biodegradation and biocompatibility improvement and some mechanical characteristics as strength and Young modulus were performed ceramic coatings on the metallic base material. The aim of this study is to characterize from the point of view of microstructural and mechanical properties like scratch and micro-indentation analysis some ZrO₂-CaO and ZrO₂-Y₂O₃ coatings with similar thickness deposited using an atmospheric plasma spraying facility. Morphological and microstructural evaluation is studied using SEM and XRD analysis. For - 276 - mechanical characteristics, coatings are supposed to comparative analysis of microindentation and scratch analysis in order to study the adhesion properties between the coatings and the substrates.

11 illus, 4 tables, 18 ref

016173   Bhattacharyya S K (Civil Engineering Dep, , IIT Kharagpur, Email: srimankb@gmail.com) : Tuned sloshing damper in response control of tall building structure. Proc Indian Natn Sci Acad 2016, 82(2), 223-31.

The paucity of space and requirements of building infrastructure has driven us to explore for taller building systems. Also a large number of construction materials has emerged and are being used extensively in buildings. The usage of light weight high strength materials reduces the space requirement and also becomes economical. However, such structures have structurally become susceptible to the lateral loading generated due to wind or earthquake. Attempts are made to control the response of tall building systems by introducing control mechanisms in the form of active, passive or hybrid system. Usage of liquid storage tanks in tall building system in the form of a passive control device proves effective. Several works have been carried out in the past to understand the efficacy of such system, which popularly is known as tuned liquid dampers or tuned sloshing dampers (TSD). The present paper deals with the development of a numerical code to demonstrate the efficacy of such tuned sloshing damper considering fluid structure interaction effect.

5 illus, 2 tables, 18 ref

016172   Barman P;Dhekial N;Deka D K;Sakia B;Gogoi B J;Robha B;Talukdar P (NO, , ) : Experimental analysis of the effect of fine milled husk of rice as a novel filtration control agent for water based drilling fluid system. J Petrol Engng Technol 2017, 7(1), 4-8.

Drilling operation is a - 275 - complex process that requires integration of various engineering systems. As the drilling continues, the formation encountered offers challenges la wellbore integrity as pressure in reuses with depth. The influx of formation fluid is contained by the overbalance provided by weighted drilling fluid column. Another critical function of the mud is to restrict the filtration fluid lost to the formation by forming a suitable mud-cake around the welllbore. Drilling fluids are designed In reduce filtration loss by addition of filtration control agent. This paper is a comprehensive study of the effects of fine milled Husk of Rice as a filtration control agent in water based mud system by experiments performed at laboraory conditions. Filter Loss and Rheological properties of the mud were studied by changing the concentration of the Husk of Rice in water based mud system.

016171   Banshwar A;Sood Y R;Shrivastava R (NO, , ) : Disaggregated optimization approach for competitive procurement of energy and operating reserve. J Pwr Elect Pwr Syst 2016, 6(3), 33-41.

In restructured environment, Ancillary Services (AS) plays a vital role, as they are required for reliable and secure operation of the power system. Operating Reserve (OR), as one of the main AS, is a capability of a power system to prevent any unexpected imbalances caused by generation, transmission or equipment outage has been considered in this work- The approach is based on disaggregated clearing of energy and OR, which can support the development of an effective reserve allocation and pricing methodology. This approach is based on sequential clearing of Energy Market (EM) and Reserve Market (RM) with the objective of procurement cost minimization. The optimization problem is formulated and solved using Optimal Power Flow (OPF) technique which considers all transmission constraints and power flow limits. In this model, the energy is procured first in EM followed by OR in RM. The procurement of both energy and OR using sequential approach has been demonstrated by considering modified IEEE 5-unit test svstem.

016170   Banjare J;Agrawal A;Sahu Y K;Satapathy A (Mechanical Engineering Dep, College of Engineering & Technology, Raipur-491 441, Email: alokag03@gmail.com) : Analytical and experimental investigation of particulate filled polymer composites with enhanced thermal conductivity. Indian J Engng Mater Sci 2016, 23(6), 389-98.

The present study aims at investigating an opportunity of enhancing heat conduction ability of a typical particulate filled polymer composite. A mathematical correlation for evaluating the effective thermal conductivity (k_eff) of polymer composites filled with elliptical shape particles is developed. To validate this model, high thermal conductivity aluminium powders were incorporated in the epoxy matrix for the first set of polymer composites whereas, for the second set, an industrial waste, i.e., red mud is taken as a filler material. Simple hand lay-up technique is used for fabrication purpose.Thermal conductivities of these fabricated composite samples are determined experimentally using the Unitherm^TM Model 2022 tester which works on the principle of double guarded heat flow meter method according to ASTM E1530 standard. Measured values are then compared with the values obtained from the proposed mathematical model and also with some already existing correlation. It has been observed that the results obtained from the proposed model fits well with the experimental data. An improvement of about 260% in the value of k_eff is recorded with addition of 25 vol % of aluminium filler in epoxy resin whereas with similar loading of red mud, it is noticed that k_eff increases by about 200%. Apart from this thermal investigation, physical properties like density and void content along with morphological behaviour of the fabricated composites are also reported.

5 illus, 3 tables, 29 ref

016169   Bakshi S;Thakur T;Khanna R (Electrical Engineering Dep, PEC Univ of Technology, Chandigarh, Email: surbhi_pec@yahoo.com) : Performance analysis of a novel hybrid optimization technique for sizing and placement of DG units. J scient ind Res 2017, 76(4), 203-7.

In today's scenario Distributed Generation (DG) resources have gained a lot of attention due to their positive impact on distribution system. Multisource hybrid power generation system with the utilization of Renewable Energy Resources (RES) is of greater concern considering environmental aspects. The considered resources are photovoltaic panels, wind turbine and battery storage. This paper attempts to solve this problem using a hybrid Modified Human Opinion Dynamics Gravitational search algorithm (MHODGSA) based Optimization algorithm and compares the solution of the stated multi-objective problem with that of (Gravitational search algorithm) GSA optimization techniques for 33 Bus Distribution System. The results of MHODGSA method is found to be moderately better than the GSA method in terms of accuracy while there is a significant improvement in terms of convergence.

3 illus, 3 tables, 16 ref

016168   Aravindan S;Thiruvenkatasamy K (Harbour and Ocean Engineering Dep, AMET Univ, 135, East Coast Road, Kanathur, Chennai-603 112, Email: swamy2667@gmail.com) : Modelling coastal sediment transport for harbour planning. Indian J Geomar Sci 2017, 46(2), 405-13.

The study provides a detailed account on the performance and limitations of Cuddalore port breakwaters based on an analysis made on the sediment pattern in breakwaters area of Cuddalore port using MIKE21 modelling software. Possible solutions for the problem are also demonstrated.

7 illus, 2 tables, 21 ref

016167   Ali S K Z;Dey S (Civil Engineering Dep, Indian Institute of Technology Kharagpur, Kharagpur-721 302, Email: sdey@iitkgp.ac.in) : Scaling laws of rough turbulent flows from turbulence phenomenology: An overview and a new application. Proc Indian Natn Sci Acad 2016, 82(2), 341-8.

In this paper, the scaling laws of rough turbulent flows stemming from the phenomenological theory of turbulence are reviewed. It is revealed that the scaling of the well-known empirical formulae can also be obtained by means of the phenomenological theory. The phenomenological theory thus enables to provide an insight into the physics of the flows of the problems arising from turbulence. As a new thought, the famous scaling laws of the velocity distributions, the logarithmic law and the power law of the wall, are also sought applying the same theory.

2 illus, 21 ref

015193   Teja T S;Vaghela M B;Chatterjee A (Aerospace Engineering Dep, Indian Institute of Technology, Bombay, Mumbai-400 076, Email: avjit@aero.iitb.ac.in) : Reducing aircraft radar cross section with owl wing type serrated trailing edges. Curr Sci 2017, 112(5), 1020-3.

Serrations at trailing edges of aircraft wing have long been known to suppress flow noise by suitably altering the flow at the trailing edge. Serrations at trailing edges are now also being used to reduce surface edge return contribution in scattering of electromagnetic waves by combat aircraft wing in order to reduce detectability by radar. A study was carried out on the efficacy of trailing edge serrations found in the wing of a barn owl, formed by its primary remiges or flight feathers, towards minimizing trailing edge related contributions by a common combat aircraft wing in an electromagnetic field. The barn owl is especially well known for its silent flight which is usually attributed to multiple adaptations in its wings including at the trailing edge. Barn owl type trailing edge serrations are appended to a planar metallic delta wing and subjected to an incident electromagnetic field. Electromagnetic scattering is predicted by numerically solving Maxwell's equations using a finite volume time domain method and the radar cross-section calculated.

5 illus, 12 ref

015192   Sonkar P;Rahi O P (NO, , ) : Proposed modified PID load frequency contoller for two area interconnectes system employing frequency regulation techniques of wind power plant. J Alternate Energy Sour Technol 2017, 8(2), 1-10.

Frequent switching of load introduces noisy ambiances and makes the implementation of conventional PID controller challenging, as differential part of controller is noise sensitive. Thus, this paper proposes a modified PID load frequency controller for two area - 241 - interconnected system, employing frequency regulation techniques of wind power plant, and compares the performance of modified PID loud frequency controller with the conventional PID controller. Wind power plant with inertial control has been compared with combination of inertial and droop control. Modified PID controller has been simulated for wind turbine without frequency regulation capabilities and with inertial control as welI as combination of inertial and droop control in MATLAB/SIMULINK ver. 2013. The significance of this work lies in the fact that it presents comparative analysis of different load frequency controllers and frequency regulation techniques of wind turbine in load frequency control regime, and shows reduction in frequency and tie line power deviations with frequency regulation techniques.

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015191   Sloanki N;Patel J K (NO, , ) : Photovoltaic solar farms operating in var mode. J Pwr Elect Pwr Syst 2016, 6(1), 73-85.

The PV solar inverter plays a vital role in solar farms for electrical power generation at distribution end. By generating active power, such at lower distributed end results like voltage rise issues and voltage fluctuations which affect power quality standards. Increasing penetration level of distributed generation sources connected to the power system cause increasing reverse power flow when demand is not adequate, which raises the voltage level at point of common coupling at grid connection. For regulation of voltage at such PCC, FACTs devices based on power electronic converter are in practice. During night time or some cloudy days, when PV system is unable to generate active power, photovoltaic inverters are utilized for reactive power support to the grid. Here, various control techniques for utilization of PV inverter operating in VAR mode are reviewed. When active power is not available by PV inverter, various methodologies for reactive power control, voltage regulation and control of load reactive power have been mentioned by useful literature survey. The role of inverter as FACTs device for reactive power compensation is elaborated comprehensively.

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015190   Singh V;Singh A (Civil Engineering Dep, National Institute of Technology Patna, Patna-800 005, Email: asingh@nitp.ac.in) : Variation of temperature and rainfall at Patna. Mausam 0000, 68(1), 161-68.

In this paper, the variation of temperature and rainfall at Patna are analysed using simple non-parametric tests. The trends in the annual maximum and minimum daily temperatures, annual rainfall, annual maximum daily rainfall, number of rainy days in a year, the annual average rainfall per rainy day and the ratio of maximum to average rainfall per rainy day at Patna have been examined. Tends in total monthly rainfall, Highest daily rainfall in a month and number of rainy days in a month have also been determined for every month in a year. The monthly trends of data using simple Mann-Kendall test indicated statistically significant changes in rainfall pattern for the city.

6 illus, 3 tables, 36 ref

015189   Si L;Wang Z;Tan C;Liu X;Xu X (School of Mechatronic Engineering, China Univ of Mining and Technology, Xuzhou 221116, China, Email: wangzbpaper@126.com) : Feature extraction method for shearer cutting pattern recognition based on improved local mean decomposition and multi-scale fuzzy entropy. Curr Sci 2017, 112(11), 2243-52.

Aiming at accurately identifying shearer cutting patterns, this article proposes a new feature extraction method based on improved local mean decomposition (LMD) and multi-scale fuzzy entropy (MFE). The cubic trigonometric Hermite interpolation was used to calculate local mean and envelope estimate functions to improve LMD decomposition results and a sum of product functions was acquired. - 240 - Furthermore, MFE, referring to the calculation of fuzzy entropy over a range of scales, was designed to measure the complexity and self-similarity of vibration signals and extract the features from the decomposition results. Subsequently, the obtained feature vectors were fed into two classifiers of support vector machine and back propagation neutral network to realize the cutting pattern recognition. The experimental results indicate the applicability and effectiveness of the methodology and demonstrate that the proposed algorithm could perform better in identifying different cutting categories of shearer.

11 illus, 2 tables, 42 ref

015188   Sharma R K;Pandey M K;Agrawal S K (NO, , ) : Enhancement in RMPA parameters using slotted rhombus connected square shaped antenna with left handed metamaterial. J VLSI Des Tool Technol 2017, 7(1), 49-54.

In this paper rectangular micro strip patch antenna (RMPA) along with metamaterial which has design of "slotted rhombus connected with rectangular shaped cover structure" is proposed at height of 3.2 mm from the ground plane. The RMPA with proposed metamaterial structure is designed to resonate at 2.7 GHz frequency. This work is mainly focused on increasing the potential parameters of micro strip patch antenna. Proposed metamaterial design structure significantly reduces the return loss and increases the bandwidth and directivity of the antenna as compared to RMPA alone. The bandwidth is increased up to 27.9 MHz in comparison to RMPA alone. The return loss of proposed antenna is reduced by 18 dB by incorporating the proposed metamaterial structure. For simulation purpose, CST-MWS software has been used.

015187   Sharma A;Sharma S K;Sharma P (NO, , ) : Novel approach based on chip high speed optical interconnection network. J VLSI Des Tool Technol 2017, 7(1), 41-8.

On-chip optical interconnects (OIs) have the potential to outperform electrical wires and to ultimately solve the communication problem and obtain high-performance integrated circuits. On-chip interconnects are an important performance limiting factor in present day VLSI design. Performance optimization has always been a critical step in the designing of integrated circuits. In this paper, an optical interconnect in 1550 nm range is being implemented using opti-system software. A novel approach is being established in this paper for an optical interconnect.

015186   Satpathy P (NO, , ) : Implementation of carry select adder with reduced area scheme. J VLSI Des Tool Technol 2017, 7(1), 1-5.

Addition is the heart of - 239 - arithmetic unit and the arithmetic unit is often the work horse of a computational circuit. So, adders play a key role in designing on arithmetic unit and a/so many digital integrated circuits. Carry select adder (CSLA) is one of the fastest adders used in many data processors and in digital circuits to perform arithmetic operations. But CSLA is area-consuming because it consists of dual ripple carry adder (RCA) in the structure. To reduce the area of CSLA, a CSLA with binary to excess-1 convener is a/ready designed which reduces the area of adder. But there are other techniques to design a CSLA to reduce its area. One of such technique is using an add-one circuit technique. This paper proposes the design of square root CSLA (SQRT CSLA) using add one circuit with significant reduction in area.

015185   Sathar R S;Gandhi P P (NO, , ) : Analysis and implementation of folding and interpolating analog to digital converter using submicron CMOS technology. J VLSI Des Tool Technol 2017, 7(1), 35-40.

This paper presents folding and interpolating ADC with resolution of 5 bit. The simulation result is carried out using 0.18 μm CMOS process technology with supply voltage 1.8 V. This folding and interpolating ADC consumes less power than other and it is 10 mW. The rate of conversion is 50 MS/S. So, it is suitable for low power application and medium resolution portable devices.

015184   Rahim A H M A;Kamal R M (NO, , ) : PWM based series compensator for power system performance enhancement. J Pwr Elect Pwr Syst 2016, 6(1), 12-25.

Enhancement of power svstem stability through a relatively new FACTS device named pulse width modulated series compensator (PWMSC) in the transmission line has been investigated in this article. The three-phase PWMSC is realized with a simple pulse width modulated (PWM) AC link converter consisting of four force-commutated switches and a three-phase diode bridge. The PWMSC is modeled as a continuously controllable series capacitive reactance in the transmission line of a power system. Nonlinear model of single machine infinite bus (SMIB) and multi-machine power system with PWMSC installed are derived and tested for various disturbances including three phase faults in the system. Proportional-iniegral-derivative (PID) controllers' are incorporated to control the duty ratio of the switches of the PWMSC, thus controlling the equivalent injected line reactance. Effectiveness of different stabilizing input signals for the supplementary controllers has been investigated. A real-coded genetic algorithm has been employed to optimize the controller parameters. The effect of PWMSC placement in the multi-machine svstem in power system stabilization is also explored. From a number of simulation studies on a single machine infinite bus system and also a multi-machine power system, it was observed that the proposed with optimally tuned controllers provide excellent damping characteristics to power system transients.

015183   Patel N K;Suthar B N (NO, , ) : Comparative study on particle swarm optimization for transmission congestion management. J Pwr Elect Pwr Syst 2016, 6(1), 86-93.

This research aims to propose solution to the issue of transmission congestion management based on optimal generation rescheduling using different variants of particle swarm optimization (PSO). In deregulated electricity market era, congestion management plays an essential role to accommodate all transactions - 238 - within reliable system operations. Intending to reduce the congestion cost, optimum numbers of generators are selected based on generator sensitivity factor (GSF) to perform active power generation rescheduling. The capabilities of different variants of PSO viz. CPSO, TVIW-PSO, TVAC-TVIW PSO and RANDIW-PSO have been evaluated to deal with the challenge of transmission congestion management in pool electricity market model. The PSO variants have been tested on IEEE-39 bus and IEEE-118 bus test systems. The results demonstrate that RANDIW-PSO performs better in case of minimizing congestion cos! along with satisfying system operational constraints. The work has also been extended for hybrid electricity market model with bilateral contracts. The scope of this research includes assistance to grid operator to manage transmission congestion in pool as well as hybrid electricity markets.

015182   Patel H;Sheth C V (NO, , ) : Study of cascaded H bridge multilevel inverter. J Pwr Elect Pwr Syst 2016, 6(1), 45-54.

The inverters are now-a-days used broadly. Inverters are classified as two level inverters and multilevel inverters. There are too many limitations; conventional inverters at high power and high voltage applications. So, multilevel inverters become useful for high power and high voltage applications clue to their increased number of levels at the output voltage. The harmonics are reduced by increasing the number of levels and output voltage has a tendency to-end-up more unadulterated i.e., sinusoidal. Multilevel inverter have three sorts of topologies like; first one is DCMLI (Diode clamped multilevel inverter), second one is FCMLl (Flying capacitor multilevel inverter) and third one is CHBML1 (Cascaded H-bndge multilevel Inverter), CHBMLI is a promising topology when compared to the other topologies. It reaches to higher output voltage and power levels for which the reliability is higher due to its modular topology and simplicity. The imperative element of multilevel inverter is total harmonic distortion. This paper analyzes the THD in 5, 7 and 9 levels of cascaded H-bridge multilevel inverter utilizing SPWM control technique. For worthy control in the yield voltage of inverter SPWM control procedure is utilized, as apart of the terminating circuit. The analysis has been simulated using MATLAB/SIMUL1NK technique.

015181   Patel C;Desai K (NO, , ) : Performance comparison of control approaches for improving power quality by DSTATCOM. J Pwr Elect Pwr Syst 2016, 6(1), 26-33.

Power quality is very important consideration for electrical supplv system. A number of methods like active-passive filters, dynamic voltage restorer, distribution static compensator (DSTATCOM) etc; are used to compensate the power quality problems like harmonics, voltage sag and swell, load balancing and others. This paper presents performance comparison of two control strategies used for DSTATCOM to mitigate the problems of harmonics in distribution network. The DSTATCOM, a shunt connected device is used to mitigate the harmonics generated by non-linear loads in industries. The synchronous reference frame theory (SRFT) and unit voltage template and PI controller based control strategies can be efficiently applied for DSTATCOM. The working of DSTATCOM is checked for non-linear loading condition. The svstem considered is simulated in MATLAB/Simulink, The results clearly show the effectiveness of DSTATCOM in the field of power quality with various control methods.

015180   Ouanani M;Tiliouine B (Civil Engineering Dep, Ecole Nationale Polytechnique, EI Harrach,16200 Algiers, Algeria, Email: boualem.tilliuine@g.enp.edu.dz) : Progressive Seismic Failure of a Highway Bridge, Including Abutment-Backfill Interaction. Curr Sci 2017, 112(2), 355-63.

Current engineering practice pays little attention, if any, to nonlinear abutment-backfill soil interaction (ABSI) effects on seismic behaviour of bridges. The primary focus of this article is to assess the influence of ABSI on the progressive seismic failure of bridge structures. Emphasis is placed on the significance of ABSI effects, including abutment behaviour and backfill soil flexibility. Nonlinear dynamic analysis is performed using a bilinear hysteretic model for the bridge superstructure and nonlinear characteristics of the expansion joint. Results indicate that ABSI has a significant effect on the seismic response in the longitudinal direction and can effectively reduce bridge seismic demands. ABSI affects rotational ductility demand at pier ends of the bridges, relative displacements, - 237 - pounding and axial forces in the restrainers. Thus, it is essential that numerical models used in seismic assessment of bridge structures properly consider abutment-backfill interaction.

7 illus, 3 tables, 18 ref