017617   Tomar M;Sharma N;Vineet Kumar (NO, , Gitam Kablana, Jhajjar, Harayana, Email: Mohitkumar295@gmail.com) : Shell thickness for investment casting process. Int J latest Technol Mgmt appl Sci 2012, 1(4), 19-24.

To compete in today's industry environment, companies must keep up with the leading technologies and processes and also push the boundaries and develop new and improved products and processes. Shortening the lead-time for introducing a new product to the market has always been important to maximize profits and competitiveness. Recent developments in Computer Aided Design (CAD) technologies have significantly reduced the overall design cycle. However, the manufacturing process of the production mold still relies on slow and expensive machining processes. The Manufacturing Industry is an area where time, efficiency and accuracy are the major driving forces behind innovation and research. The most competitive companies are those who continually reduce process times, increase efficiency and improve accuracy. Rapid Prototyping is an area that has and is continuing to reduce production time and increase efficiency and accuracy in developing and manufacturing prototypes compared to traditional prototype manufacture. The research development of Rapid Prototyping (RP) is to give the Rapid manufacturing the needed confidence to go on to customized/tailor made product.

25 ref

017616   Tomar M;Sharma M;Vineet Kumar (NO, , Gitam Kablana, Jhajjar, Haryana) : Step over influence on cyclic time, using taguchi design method. Int J latest Technol Mgmt appl Sci 2012, 1(4), 30-4.

Usually the previous end milling experimental study based on spindle speed, feed rate and depth of cut and these cutting parameters are use for optimization of end milling operations, Due to the highly competitive Global competition and precision product requirements other important machining parameter must be optimise for the best process optimization. This research effort focuses on the role of the stepover ratio in CNC end milling operations and it was investigated in order to minimize cyclic time, milling power and surface roughness. In the present work, Taguchi's technique for Design of Experiment L9 (3⁴) Orthogonal Array (OA) has been explored to produce 9 pocket by end milling operation on mild steel workpiece. The mild Steel is processed at a digitally controlled computerized numerical control (CNC) milling using cutting fluid with three different levels of experiments. The optimum condition for the quality characteristics and contribution of individual parameters have been establish through ANOVA of raw and signal to noise ratio analysis.

2 illus, 7 tables, 6 ref

017615   Thakur G S;Gupta P;Singhal P K;Thakare V V (Electronics Dep, Madhav Institute of Technology and Science, Gwalior-474 005, Email: govindbest87@gmail.com) : Design and analysis of dual band equal split N-way Wilkinson power divider. Curr Trends Inf Technol 2013, 3(1), 17-20.

Design and analysis of dual band equal split. N-way Wilkinson power divider is proposed in this specific -work. For this the design of 2-way 4-way, 5-way and 6-way power divider is made with the help of an N-way power divider. An isolation resistor is used to achieve good isolation at output port of Wilkinson power divider. Parameters of the proposed configuration are calculated at the centre frequency of 1 GHz. For verification the proposed design is simulated with the dielectric constant of 4.4 and loss tangent of 0.02. The result is having dual band response at 1.1 GHz and 3.3 GHz. Return loss at all the ports below -10 dB, transmission coefficient above -10log (N) dB and isolation among output ports are better than -10 dB is achieved. Results of all Wilkinson power divider are., calculated by computer simulation technology microwave studio and found satisfactory.

9 illus, 1 table, 3 ref

017614   Surinder Kumar;Meenu;Satsangi P S (Mechanical Engineering Dep, National Institute of Technology, Kurukshetra-136 119, Email: surinder.asd@gmail.com) : Genetic algorithmic approach for optimization of surface roughness prediction model in turning using UD-GFRP composite. Indian J Engng Mater Sci 2012, 19(6), 186-96.

Machining of glass fiber reinforced plastic composite materials is an active area of research in current manufacturing processes. Achieving an improved surface finish is of high priority while machining the polymer based plastics composites due to the poor machinability of glass fibers. The present work deals with the study and development of a surface roughness prediction model for machining unidirectional glass fiber reinforced plastics (UD-GFRP) composite using multiple regression methodology and genetic algorithm approach. The experimentation is carried out with polycrystalline diamond tool, covering a wide range of machining conditions. A second order mathematical model in terms of machining parameters is developed for predicting the surface roughness using multiple regression methodology. An attempt has also been made to optimize machining parameters to minimize surface roughness. The model developed has been further validated.

4 illus, 10 tables, 34 ref

017613   Singh B;Mistri B (Civil Engineering Dep, IIT, Guwahati, Email: baleshwar@iitg.ernet.in) : Geotechnical analysis of steeped gravity walls. Recent Trends Civil Engng Technol 2012, 2(1), 1-10.

Retaining walls are structures that help to maintain different elevations of the ground surface on either side of it. When the height of cut, backfill or slope is beyond a certain limit, a single gravity retaining wall- becomes unfeasible and uneconomical. In such situations, stepped gravity walls can, be an attractive option. The wall at each level of the retaining system should be checked for safety against sliding, overturning and bearing capacity failure. Apart from these, a global stability check is necessary. The paper outlines the analysis approach for such stepped retaining walls that can be used for various purposes in site development.

7 illus, 2 ref

017612   Shukla S K (Polymer Science Dep, Bhaskaracharya College of Applied Sciences, University of Delhi, Delhi-110 075, Email: sarojshukla2003@yahoo.co.in) : Synthesis of polyaniline grafted cellulose suitable for humidity sensing. Indian J Engng Mater Sci 2012, 19(6), 417-20.

Polyaniline-grafted-cellulose (PANi-cellulose) copolymer is prepared by a chemical method using cupric sulphate as initiator. The representative PANi-cellulose samples are characterized by Fourier transform infrared spectroscopy (FTIR), thermal gravimetric differential thermal analysis (TG-DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The data reveal the formation of electrically conducting and hydrophillc copolymer. The film of PANi-cellulose is casted on a glass slide by spin coating technique and used for humidity sensing of a controlled humid environment by monitoring electrical resistance. The resistance continuously decreased from ~ 32 MΩ to 10.0 MΩ with increase in relative humidity in the range of 5- 90%. The observed sensing parameters are sensitivity 0.22, response time 40 s, recover time 60 s and stability for more than 60 days.

8 illus, 26 ref

017611   Sharma M K;Buddhi D (Mechanical Engineering Dep, Millennium Institute of Technology, Saharanpur, Email: muneshhec@gmail.com) : Use of refrigerating technologies in cold chain solution: a state-of-the-art. J Alternate Energy Sour Technol 2012, 3(2), 39-60.

This paper reviews the development of cold thermal storage technology. In this work, a review has been carried out of the operating strategies, management and thermal load, cold storage types and storage media, current and alternative possible technology for food transport refrigeration and thermoelectric cooling and power generation used in the cold chain. Conservation and transport of temperature-sensitive materials and applications are discussed.

8 illus, 89 ref

017610   Sharma M K;Buddhi D (Mechanical Engineering Dep, Millennium Institute of Technology, Saharanpur, Email: muneshhec@gmail.com) : Temperature variation and energy performance with or without PCM due to introduction of heat loads. J Alternate Energy Sour Technol 2012, 3(2), 19-38.

Food transport and storage at low temperatures has always been an important matter worldwide and is becoming even more important due to dietary needs and population growth. The issue of improving food storage applies to food transportation in refrigerated vans and food storage in domestic refrigerators and freezers. In this paper, heat loads are introduced into a freezer and vegetable zone through short door openings (five door openings lasting 1 min each and spaced at 30 min intervals) and single 3 min door opening with and without phase change materials (PCMs) with static conditions (no fan to circulate cold air) and with dynamic condition (with fan to circulate cold air) ambient air through the walls. Also the performance of PCM inside the refrigerator (freezer and vegetable zone) with varying the mass with surface area in both static and dynamic conditions was investigated. The temperature responses of the freezer with and without PCM are examined, with regards to heat loads introduced through door openings and power loss. Energy consumption of the refrigerator with and without PCM is also investigated.

24 illus, 4 tables, 10 ref

017609   Sharma A;Srivastava J (NO, Rajiv Gandhi Institute of Petroleum Technology (RGIPT), Rae Bareli-229 316, Email: atul_sharma2@yahoo.com) : Biomass energy - a sustainable option for power generation in rural India. J Alternate Energy Sour Technol 2012, 3(1), 1-19.

Energy is the basic driver of growth. Socio-economic growth is not possible unless energy security is ensured. The demand for energy in India is growing at a rapid rate. India is the world's fifth largest energy consumer. This rapid growth in demand can be attributed to rise in population and increasing economic development. However, there is a great gap between demand and supply of energy in the country. India depends heavily on coal and oil for meeting its energy demand which contributes to smog, acid rain and greenhouse gases emission. Last 25 years has been a period of exuberant hunt of activities related to research, development, production and distribution of energy in India. Indian economy has been growing at a rapid and impressive pace, averaging over 8% during last few years. India's need to increase energy provision for its population and a fast-growing economy poses a formidable challenge which is perceived as both a great opportunity as well as a necessity for the country to increase the share of renewables in the overall energy mix. India is making efforts to harness the potential of renewable energy resources such as biomass, solar, hydro, wind and geo-thermal energy. Renewable energy sources have emerged as a viable option to achieve the goal of social-economic development while ensuring environmental protection. The aim of this paper is to bring into focus the biomass energy that can be tapped to meet the country's energy requirement.

2 illus, 1 table, 26 ref

017608   Shankarkumar A;Shankarkumar U (TTD Dep, National Institute of Immunohaematology, 13th Floor, KEM Hospital, Parel, Mumbai-400 012, Email: arp21@rediffmail.com) : Role of HLA-A, HLA-B, HLA-DRB1 and HLADQB1 alleles in HIV-1 patients with pulmonary tuberculosis co-infection from India. Indian J Hum Genet 2012, 12(1), 11-13.

Studied the role of HLA HLA-A, B, DRB1 and DQB1 in HIV-1 patient's co infected with pulmonary tuberculosis (PTB). A total of 102 HIV-1+ patients co-infected with pulmonary tuberculosis and 200 healthy controls were included in HLA analysis. HLA-A*, HLA B* HLA-DRB1* and DQB1 *typing was done molecularly by PCR-SSOP (Polymerase Chain reaction-Sequence Specific Oligonucleotide Probing) method using kit (Dynal Kit- Invitrogen). The frequencies of the HLA-A*, HLA-B* HLA-DRB,1* and HLA-DQB1* alleles were determined using standard software. The HLA alleles identified among HIV+ve/PTB+ve co-infected patients was compared with healthy controls. Our results showed a significantly increased frequency o HLA-B*08:01:01(p=0.011, OR 3.335,95% CI 1.35-8.18) HLA-DQBl*03:01:03(p<60>0.0001, OR 107.5, 95%CI 6.195-1865.3) in HIV+ve/PTB+ve co-infected patients when compared with healthy controls. Similarly HLA-DQB*06:01:02 (p=0.003, OR 4.808, 95% CI 1.72-13.39), HLA DQB1*03:01:01 (p=0.045, OR 0.219, 95% CI 0.051-0.940), HLA-DQB1*06:01:01:01 (p=0.012, OR 0.334, 95% CI0.145-0.770), allele frequency was observed in HIV+ve/PTB+ve co-infected patients when compared with healthy controls. We can conclude that different HLA alleles may render susceptibility or protection to in different ethnic population.

1 table, 13 ref

017607   Sehgal V;Sahay R R (Civil Engineering Dep, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, Email: vinitsehgal281991@gmail.com) : Monsoon flood forecasting in Gandak river using discrete wavelet transform. Recent Trends Civil Engng Technol 2012, 2(1), 11-19.

Gandak River in North Bihar carries huge flood during the monsoon period. The daily variation in its flow during this period is so significant that conventional methods find it difficult to model the flow. In this paper, new models employing discreet wavelet transform (DWT) have been developed to forecast daily flows in a large river like Gandak. DWT decomposes the flow series into constituent wavelet components of "approximations" and "details. " After removing the most uncorrelated "detail" from the original flow series and recombining other wavelet components, a modified flow series is reconstructed. Five wavelet regression (WR) models are developed for the forecasting of the current-day flood. Predictions from WR models are compared against that from auto regressive (AR) models developed for the purpose. Based on various performance indices, it can be concluded that WR models have strong generalization ability and predict large floods with greater accuracy than AR models.

5 illus, 3 tables, 8 ref

017606   Samal B P;Misra A K;Panigrahi S C;Mishra S C (Mechanical Engineering Dep, Maharaja Institute of Technology, Taraboi, Khurda, Odisha, Email: b_p_samalrx100@yahoo.co.in) : Novel technique for improved recovery of Mg-analysis of the microstructure and physical properties. J Mater metall Engng 2013, 3(1), 1-7.

Aluminium-Magnesium alloys are used widely in industrial applications as well as for the preparation of metal matrix composite because of their low density and high specific strength. Magnesium has a low boiling point and the recovery of magnesium is poor when it is added in pure form particularly as cheaply available turnings to the liquid metal. Magnesium is added to aluminium for increasing its wettability and thus helping in uniformly distributing ceramic particles used as reinforcement. There have been very few attempts to use the magnesium turnings to produce cast Al-Mg alloys in the range of 3-15% magnesium. A modified stir casting technique was developed using a plunger for making alloy addition by the casting route utilising cheap magnesium turnings. The recovery of Mg was close to 90% and even higher, when added in the form of turnings. In this paper, the density of Al-Mg alloy is predicted with a quadratic model. Also, the percentage of decrease in density for the magnesium alloys increased with increase in magnesium addition and the relation can be represented by a quadratic equation. This technique will be effective on improving the recovery of alloy additions with low density high volatility.

12 illus, 4 tables, 8 ref

017605   Ravichandran C P (NO, Welding Research Institute, BHEL, Tiruchirappalli-620 014) : Influence of Ti-B microalloying additions on sub-zero notch-toughness of AWS E7018 electrode all-weld metal deposits. WRI Jl 2011, 32(4), 23-8.

SMAW electrodes with various coating types deposit weld metal with various combinations of mechanical properties like tensile strength, elongation and notch toughness. In the case of ferritic, weld metals,basic coated low hydrogen electrodes show a lower Charpy-Vee notch impact transition temperature when compared with other type of coatings like rutile coating and cellulose coating. Hence they are used in applications, where a good combination of strength, toughness and freedom from risk of cold cracking are necessary. AWS E 7018 electrodes are tested at minus 30°C for CVN impact properties. Experimental electrodes were designed and tested through a factorial testing method to understand the influence of simultaneous micro-alloying additions of titanium and boron on the CVN impact properties of all weld metal at minus 30°C. The results show that Ti and B show a synergistic effect. The results are explained on the basis of nucleation and growth of acicular ferrite.

2 illus, 9 ref

017604   Rana P;Tomar M;Sharma N (EE Dep, Sat Kabir Institute of Technology and Management, Dist. Jhajjar-124 507) : Electrical power generation systems. Int J latest Technol Mgmt appl Sci 2012, 1(4), 50-5.

9 ref

017603   Rana P;Tomar M;Kumar V (EE Dep, Sat Kabir Institute of Technology and Management, C, Email: pranarohtak@gmail.com) : Comparison of voltage stability to improvement power quality. Int J latest Technol Mgmt appl Sci 2012, 1(4), 65-7.

Aim of this paper to improve the voltage regulation in a transmission system through FACTS devices, complete close-loop smooth control of reactive power can be achieve the using shunt connected FACTS devices STATCOM is one of the shunt connected FACTS device, which can be utilize for the purpose of reactive power compensation. This paper is present the Comparisons of FACTS Devices on the basis of its terminal characteristics and conclude, which FACTS device is better for effective voltage stability to improve power quality of the transmission system.

8 ref

017602   Rana P;Balhara S;Tomar M (NO, , EE Dep, Sat Kabir Institute of Technology and Management, Email: pranarohtak@gmail.com) : High-voltage DC power transmission system. Int J latest Technol Mgmt appl Sci 2012, 1(4), 81-4.

VSC-HVDC can ad- dress not only conventional network issues such as bulk power transmission, asynchronous network interconnection, back-to-back AC system linking and voltage/stability sup- port to mention a few, but also niche markets such as the integration of large scale renewable energy sources with the grid.

9 ilus, 6 ref

017601   Rajamane N P;Nataraja M C;Lakshmanan N; Dattatreya J K;Sabitha D (NO, SRM University, Kattankulathur-603 203, Email: rajamanenp@yahoo.co.uk) : Sulphuric acid resistant ecofriendly concrete from geopolymerisation of blast furnace slag. Indian J Engng Mater Sci 2012, 19(5), 357-67.

In this study, geopolymer is prepared from `ground granulated blast furnace slag' (GGBS)-a powder from grinding the by-product of slag waste from blast furnace of steel plants. For comparison, conventional cement, Portland pozzolana cement (PPC) containing fly ash was considered. To achieve simultaneous acidic and sulphate attack, sulphuric acid is used for durability studies. The test data indicate that on exposure to 2% and 10% sulphuric acids, the losses in weight, thickness and strength of geopolymer concrete (GPC) are significantly much less than those for Portland pozzolana cement concrete (PPCC). The GPCs have inorganic polymers of alumino-silicates as binder, generally without any free lime. Therefore, GPCs resist acid attack better than free lime containing conventional concretes containing Portland cement. The binding action in GPC is through geopolymerisation of GGBS using alkaline activator solution (AAS) made of sodium hydroxide and sodium silicate solutions. The geopolymer eliminates use of Portland cement in structural concretes by utilizing the industrial by-product GGBS, thereby reducing considerably the carbon footprint measured by `embodied energy' and `embodied carbon', i.e., `CO₂e emission' of concrete.

4 illus, 4 tables, 56 ref

017600   Raja J;Kannan M (Electronics Engineering Dep, MIT, Anna University, Chennai-600 044, Email: s.t.jayamani@gmail.com) : VLSI implementation of high throughput MIMO OFDM transceiver for 4<. Indian J Engng Mater Sci 2012, 19(5), 307-19.

Paper aims to maximize throughput by minimizing power as minimum as possible. Scores of optimization techniques such as FFT, IFFT and memory optimization are available for reducing power of mobile OFDM systems. An approach for achieving reduction in power of MIMO OFDM system by optimizing FFT architecture is addressed in this paper. Memory references in MIMO OFDM transceiver are costly due to their long delay and high power consumption. To implement fast Fourier transform (FFT) algorithms on MIMO OFDM, involves many memory references to access butterfly inputs and twiddle factors. Conventional FFT implementations require unused memory references to load the same twiddle factors for butterflies from different stages in FFT diagrams. To minimize memory references due to twiddle factors for implementing FFT algorithms in MIMO OFDM systems, memory reference reduction method is incorporated here. Twiddle factor is calculated using binary scaling technique. The proposed FFT structure is the combination of memory reference reduction method with binary scaling technique and Radix-4 booth multiplier. Here multipliers in FFT are realized with shifters, adders and subtractors. The proposed structure is evaluated using performance parameters such as BER and SNR. Structural realization and analysis pertaining to timing, power and throughput are implemented in Virtex-4 and analysis is carried out in Altera respectively.

23 illus, 6 tables, 16 ref

017599   Raja A;Rajasekaran N;Asokkumar K (NO, Welding Research Institute, BHEL, Tiruchirappalli-620 014) : Evaluation of the activated tig welding process for fossil boiler tube applications. WRI Jl 2011, 32(4), 5-11.

Tungsten Inert Gas (TIG) welding is widely used for root pass welding of tubes and pipes meeting the stringent quality requirements of ASME, etc. In the past two decades, numerous developments have taken place in TIG welding technology in power source, shielding gas, tungsten electrode, welding torches and joint design (Narrow gap). Though the developments such as addition of active elements to the electrode to increase the emissivity, the use of shielding gas mixtures, and the optimisation of the electrode-tip configuration enhanced the arc characteristics and improved the weld bead penetration profile, the productivity improvements were marginal. One way to enhance the productivity is to increase the penetration depth, as it helps in reducing the number of welding passes. Activated TIG welding process (A-TIG) thought to be beneficial in this respect. A-TIG welding process involves application of a thin coating of activating flux material on the joint surface prior to welding to enhance the weld penetration. The flux constricts the arc which increases the current density at the anode root and the arc force on the weld pool. Though A-TIG welding offers higher productivity, industry has been slow in exploiting this process. In this work, the effect of parameters on penetration in A-TIG welding has been discussed based on the experimental results. This work also explores the A-TIG welding process for improving the weld penetration depth and productivity for carbon steel and low alloy steel tube materials. It was found that the consistent quality, simpler edge preparation, reduced distortion and improved productivity make A-TIG welding process more attractive than the conventional TIG process for tube butt welding.

29 illus, 1 table, 2 ref

017598   Prihandana G S;Sriani T;Mahardika M (Mechanical Engineering Dep, Keio University, Yokohama, Japan, Email: g_prihandana@2.keio.jp) : Improvement of machining time in micro-EDM with workpiece vibration and graphite powder mixed in dielectric fluid. Indian J Engng Mater Sci 2012, 19(6), 375-8.

Improper flushing of debris in micro-EDM processes has created more frequent short-circuiting between a tool electrode and a workpiece resulting in longer machining process. Longer machining time (34 min) is required only to fabricate a blind hole with 500 μm of depth. In order to solve this problem, powder suspended dielectric fluid and workpiece vibration have been introduced into micro-EDM system in order to reduce the machining time. The introduction of graphite powder suspended dielectric fluid at concentration of 10 g/L has reduced the machining time up to 5 times faster than machining time in pure dielectric fluid. Whilst, the application of vibration on the workpiece has sped up the machining time up to 3 time faster than the machining process without workpiece vibration. The results conclude that the introduction of graphite powder and the application of workpiece vibration have improved the machining stability, results in a significant reduction of machining time.

7 illus, 2 tables, 24 ref

017597   Prasad K S;Rao C S;Rao D N (Mechanical Engineering Dep, Anil Neerukonda Institute of Technology & ciences, Visakhapatnam, Email: kspanits@gmail.com) : Multi objective optimization of weld bead geometry parameters of pulsed current micro plasma arc welded inconel 625 using enhanced non-dominated sorting genetic algorithm. J Mater metall Engng 2013, 3(1), 17-24.

Pulsed Current Plasma Arc Welding (PCPAW) is one of the most widely used welding processes in sheet metal manufacturing industry. In any fusion arc welding process, the weld bead geometry plays an important role in determining the mechanical properties of the weld and hence, quality of the weld. Moreover, the geometry of weld bead involves several simultaneously multiple quality characteristics such as front width, back width, front height and back height, which must be closely monitored, controlled and optimized. The present study is focused on the multi-objective optimization of performance parameters of weld bead geometry of PCMPAW welded Inconel 625 sheets. The enhanced elitist non-dominated sorting genetic algorithm (NSGA-II) is used to solve this multi-objective problem. A mathematical predictive model for each of the weld bead parameters was developed using Response Surface Method (RSM) based Central Composite Design (CCD) design matrix. Further, an enhanced NSGA-II algorithm is used to optimize the models developed by RSM. Experiments are carried out to validate the results obtained from RSM and enhanced NSGA-II.

3 illus, 5 tables, 22 ref

017596   Pavan Kumar Y V;Jaganmohan Reddy Y;Padma Raju K (Electronics and Communication Engineering, Jawaharlal Nehru Technological University, Kakinada, Andhra Pradesh, Email: yvpavankumar@gmail.com) : Interfacing renewable energy sources to the utility power grid using a motor-generator set. J Alternate Energy Sour Technol 2012, 3(1), 31-50.

This paper describes modeling and simulation of a utility grid-connected renewable energy based hybrid power system (HPS) in the aspect of improving power quality. In order to meet sustained load demands during varying natural conditions, different renewable energy sources and power conditioning units need to be integrated with each other. The paper focuses on the combination of photo voltaic (PV) cell, wind turbine (WT), fuel cell (FC), and battery systems for power generation. To improve power quality of the power system, the proposal is to use DC motor-synchronous generator set instead of conventionally used static inverters. A diesel engine is also coupled to synchronous generator as a standby prime mover to improve the reliability of the overall system during varying natural conditions like wind velocity, irradiance, temperature, etc. The proposed control algorithm acts as a bridge between load fluctuations and generating capacity, for managing available resources economically. The results show that the proposed hybrid power system can effectively manage the optimal utilization of primary energy sources and improve the power quality in both islanding mode as well as grid-connected mode.

37 illus, 1 table, 24 ref

017595   Narasimha V L;Ravi K;Amba Prasad Rao G (Mechanical Engineering Dep, National Institute of Technology, Warangal-506 021, Email: gap@nitw.ac.in) : Performance evaluation of battery electric vehicles - a computational study. J Alternate Energy Sour Technol 2012, 3(1), 51-65.

Technological innovations have brought significant developments in internal combustion engine-powered automotive vehicles. With the automotive population explosion, issues of fossil fuel crisis and environmental degradation are enticing the researchers to divert focus on alternate fuels and alternate power sources to keep the automotive industry alive. Owing to global warming and associated pollution hazards, many nations are imposing stringent emission norms. To meet the target zero emission levels, researchers are seriously working to develop viable electric vehicles. In this regard, developed nations have done their might to commercialize different variants of electric vehicles. Computer simulations are being tried out to arrive at optimal designs. Electric vehicles are powered by various power packs available commercially, viz,. Pb-acid, Ni-MH, Ni-Cad, etc., with the choice lying in the application. The present work deals with the comprehensive modeling of battery performance parameters using the software MATLAB. It deals with the evaluation of performance parameters such as acceleration performance and range considering simplified Federal urban driving schedule, European driving cycle and Indian driving cycle. Commercially available electric car JOLT EVION is chosen for validating the modeling results. Modeling studies revealed that there is still larger scope for Pb-acid power packs as others pose either environmental hazards or cost constraints. Few of the myths in the usage of electricity are found to be highly deceptive. It is felt that government incentives for automotive industry may promote commercial use of electric vehicles.

22 illus, 19 ref

017594   Mukherjee M K (Civil Engineering Dep, Jalpaiguri Govt. Engineering College, Jalpaiguri) : Studies on empirical modeling between annual peak discharge (QP) and return period (T) of river Sankosh in North Bengal using plotting position formulae. Indian J Landsc Syst ecol Stud 2009, 32(1), 358-67.

Establishing a relationship between Annual Peak Discharge (Qp) and Return period (T) for a river is extremely helpful in forecasting floods and design of important hydraulic structures. The present study aims to develop an empirical model of Annual Peak Discharge (Qp) (Mukherjee, M.K, Sarkar, S, 2007; Deterministic Modeling of Stage-Discharge Relationship of the River Sankosh, North Bengal) and corresponding Return Period or Recurrence Interval (T) computed from empirical formulae. The investigator has used Plotting Position Formulae for the development of models. The resulting model correlating Annual Peak Discharge (Qp) and Return Period (T) for the river Sankosh of Brahmputra Basin, is found to be satisfactory in terms of small percentage deviation and small standard deviation of percentage deviation of the values of Annual Peak Discharge (Qp) as obtained from mathematical models and those values obtained from the field. Moreover, values of Correlation Coefficient (r) are found to be very satisfactory as the values of correlation coefficient in all cases under the present study are varying between 0.70 to 0.95; it indicates that good correlation exists between the two parameters involved in the study.

7 illus, 6 tables, 16 ref

017593   Mangal N;Jain S;Sharma A (EC Dep, Shri USB College of Engineering & Management, c) : Design of beam tunnel for 42 GHz, 200 kW gyrotron. Int J latest Technol Mgmt appl Sci 2012, 1(4), 68-73.

Beam tunnel for a 42 GHz, 200 kW gyrotron for an Indian TOKAMAK system has been designed. The initial design of the beam tunnel has been carried out on the basis of the required electron beam parameters at the interaction cavity and the electron beam simulation of the magnetron injection gun. The design optimization of the beam tunnel has been done with the help of 3-D simulation software CST-Microwave Studio. In the simulation, the absorption, the reflection and the transmission of RF power by the beam tunnel have been analyzed. Three different lossy ceramics, Al₂O₃-SiC, AIN-SiC and BeO-SiC have been investigated during the simulation. The simulation results obtained with CST-Microwave Studio have been validated with another 3-D simulation software HFSS. The Q value of the beam tunnel for different ceramic material has also been analyzed to investigate the parasitic mode excitation in the beam tunnel.

3 illus, 3 tables, 6 ref

017592   Mangal N;Jain S;Sharma A (EC Dep, Shri USB College of Engineering & Management, ) : Subband implementation of adaptive filter. Int J latest Technol Mgmt appl Sci 2012, 1(4), 56-9.

This is a review paper which compare the different models for noise cancellation. Our purpose is to compare the performance of different models with their advantages and disadvantages. This paper deals with the concept of adaptive noise cancellation through sub-band decomposition of FIR filter and simple structure of without sub-band. The sub-band structure implements an adaptive FIR of length N as a parallel combination of L branches, with each branch composed of a cascade of a fixed interpolator and adaptive filter containing at least N/L non zero coefficients. The sub-band structure presents superior convergence performance for input signals when compared to the conventional direct form LMS structure, with a very small increase in number of operations. The advantages of using the sub-band structure are shown through the acoustic echo canceller, noise canceller and channel equalizer application.

3 illus, 8 ref

017591   Malsaria R;Srivastava V;Sharma G S (MWT Div, Central Elecronics Engineering & Research Institute (CEERI), Pilani, Rajasthan, Email: renu.malsaria@gmail.com) : Improved non-linearity of helix SWS for a high efficiency TWT. Int J latest Technol Mgmt appl Sci 2012, 1(4), 1-4.

Linearity improvement is one of the most critical issues in the development of high-power, high frequency TWT. Higher linearity allows utilizing more compact and less expensive power supplies. Furthermore, high-efficiency Travelling wave tubes can operate more reliably and have longer lifetime due to reduced collector loading. While the high-power outputs and wide gain-band widths make TWTs ideally suited for these purposes, the nonlinearity of these devices results in amplitude, phase and spectral distortion. Nonlinear distortion products appear as harmonics and for multi-carrier operation also as intermodulation products, at the output of the amplifier thus limiting the usable bandwidth of the amplifier and degrading fundamental efficiency. In this paper, design and development of a Ku-band HOW Helix TWT for improved linearity and high efficiency will be presented.

1 illus, 8 ref

017590   Maharjan R K;Kim N Y (RFIC Lab, Electronic Engineering Dep, Kwangwoon University, 447-1 Wolgye-done, Nowon-gu, Seoul-139 701, Email: rkmahajn@gmail.com) : Microstrip even-mode half-wavelength SIR based I-band interdigital bandpass filter. Indian J Engng Mater Sci 2012, 19(5), 299-303.

In this paper, a new microstrip interdigital even-mode half-wavelength type stepped impedance resonator (SIR) based bandpass filter (BPF) for I-band applications is presented. The bandpass filter characteristic depends on the self-resonant frequency of the interdigital resonated arms. The combination of the interdigital arm structures behaves as an interdigital capacitance coupling between port 1 and port 2. The self generated capacitive and inductive reactances of the interdigital resonators interacted in order to obtain a resonance at 9.4 GHz. The resonant frequency and the bandwidth of the filter are directly optimized as a result of the physical arrangement of the interdigital resonators. The measured insertion loss (S₂₁) and the return loss (S₁₁) are -0.85 dB and -28.0 dB, respectively, at the 9.4 GHz resonant frequency.

6 illus, 16 ref

017589   Lodhi S S;Singhal P K;Thakare V V (Electronics Dep, Madhav Institute of Technology and Science, Gwalior, Madhya Pradesh, Email: sslodhi1988@gmail.com) : Design of microstrip yagi uda antenna by using triangular patches. Curr Trends Inf Technol 2013, 3(1), 21-3.

Novel design of microstrip yagi uda antenna by using triangular patches at resonating frequency of 9.4 GHz is proposed. The micros trip antenna is designed by using triangular patches which improves the gain, directivity and efficiency of the antenna. The microstrip yagi uda antenna was simulated by Computer simulation technique (CST) MW studio software. In this paper, the simulated results such as radiation pattern, input impedance, return loss and smith chart are discussed and analyzed.

5 illus, 1 table, 7 ref

017588   Kumaresan M;Devaradjane G (Automobile Engineering Dep, SACS M AV M M Engineering College, Kidaripatty, Madurai-625 301, Email: phdkumar@yahoo.com) : Effect of two-springs split injection on the performance and emission characteristics of diesel-oxygenated blends in a DI diesel engine. Indian J Engng Mater Sci 2012, 19(6), 411-16.

This paper attempts to find the use of two-springs split injection with an oxygenated compound blended with diesel to address the environmental pollution issue especially in smoke and oxides of nitrogen emission reduction besides retaining the performance. Experimental investigation has been carried out to study the performance, and emission characteristics of diesel and diesel-diethyl carbonate oxygenated compounds blend in the proportions of 10% by volume in a direct injection (DI) single cylinder diesel engine using the standard single-spring injection and two-springs split injection. From the investigation it has been observed that with two-springs split injection at an injection timings of 27° before top dead center (BTDC) the brake thermal efficiency is found as 29.3%, oxides of nitrogen emission as 1.32 g/kWh and smoke level as 36% opacity with 10% diethyl carbonate-diesel oxygenated blend.

8 illus, 3 tables, 7 ref

017587   Gunes I;Kayali Y;Ulu S (Metallurgical and Materials Engineering Dep, Technology Faculty, Afyon Kocatepe University, Afyonkarahisar 03200, Turkey, Email: igunes@aku.edu.tr) : Investigation of surface properties and wear resistance of borided steels with different B₄C mixtures. Indian J Engng Mater Sci 2012, 19(6), 397-402.

Boriding is a thermo-chemical surface hardening treatment applied to iron based materials. This treatment is performed by boron element diffusing into iron based materials at high temperatures. Wear resistance increases by forming ferro-boron phases on the material surface. In addition, a very hard layer forms on the material surface. As a result, the tribological properties of the material increase. In this study, 6 different mixtures are prepared with B₄C and SiC powders. In these mixtures steels of AISI 1020 and AISI 1040 are borided with a stainless steel crucible at a temperature of 900°C for 3 h. Depending on the boriding mixtures, the thickness of the borides formed on the surface of borided AISI 1020 and AISI 1040 steels ranged from 14 to 71 æm and from 10 to 64 <109 >m, respectively. It is observed that the layer thickness increases with increase in B4C% ratio. The wear rate of steels increased with decreasing SiC ratio. The average value of obtained microhardness for borides of AISI 1020 and AISI 1040 steels are 1776 and 1860 HV0.05, respectively.

9 illus, 29 ref

017586   Gidwani L;Tiwari H P (NO, Govt. Engineering College, Near Nareli Thirth, Badaliya Chouraha, NH-8, Ajmer-305 001, Email: lata_gidwani@rediffmail.com) : Improving power system dynamic behavior through control strategies in wind energy conversion systems. J Alternate Energy Sour Technol 2012, 3(1), 20-30.

The feed-in power to the grid in Wind Energy Conversion Systems (WECS) shows always a high fluctuation resulting in power quality problems. These problems clearly show that there is a strong need for controlling various stages of WECS, such as generator control, converter control, and inverter control. This paper presents an overview of various control strategies applied to WECS. Emphasis is placed on introducing the control techniques followed by a description of methodologies adopted. The current research work being undertaken by various groups is also highlighted.

9 illus, 80 ref

017585   Fayomi O S I;Gbenebor O P;Abdulwahab M; Popoola A P I (Mechanical Engineering Dep, Covenant University, P.M.B. 1023, Ota, Ogun State, Nigeria, Email: koladepj@yahoo.com) : Performance evaluation of some steels as extrusion die on AA6063-type Al-Mg-Si alloy. Indian J Engng Mater Sci 2012, 19(6), 403-10.

Study deals with the performance evaluation of mild and tool steels, their microstructure and extrusion property associated with changes in induced dies of entry angles 15°, 45° and 75° on AA 6063-type Al-Mg-Si alloy. Based on the service requirement in extrusion operations, microhardness and wear properties are used as criteria. The extrusion operation reveals the formation of clusters, surface modification occurring as a result of various ranges of die angles. The effect of extrusion pressure, sample elongation, hardness and die speed angle are systematically studied using microhardness tester, optical microscope (OPM), scanning electron microscope with energy dispersive spectroscopy (SEM-EDS). The mild steel die enables slips and dislocation movement of the sample to take place with ease than the tool steel dies at 45° elongation. Formation of Mg2Si and AlFeSi on mild steel extrusion has significantly influenced its mechanical properties as a result of response to increasing grain boundary which serves as nucleation site for the precipitates. The microhardness and wear resistance of extruded mild steel increased by 90%. Extrusion of the aluminum by the tool steel led to the formation of clusters and stretched along the slip directions.

17 illus, 2 tables, 19 ref

017584   Das B B;Singh D N;Pandey S P (NO, Lawrence Technological Univ, Southfield, Michigan 48335, USA, Email: dns@civil.iitb.ac.in) : Pore-structural parameters of concrete, their inter-relationship and coreelation to compressive strength. Recent Trends Civil Engng Technol 2012, 2(1), 20-30.

An extensive literature review was carried out on various forms of pom structural parameters (pore diameters) of concrete such as critical pore diameter, mean pore diameter, and threshold pore diameter and their correlations to compressive strength of concrete. From the review of the literature, it has been observed that the inter-relationships among various forms of pore diameters and their correlation to compressive strength of concrete have not been discussed much in the existing literature. Hence, efforts were made to develop a simple and generalized relationship between threshold pore diameter and the compressivs strength of concrete. In addition, with the help of generated experimental database, empirical relationships were proposed correlating various forms of pore diameters such as threshold pore diameter, mean pore diameter, and critical pore diameter. The whale exercise was carried out with six grades of concrete (three with ordinary Portland cement and three with Portland pozzolana cement) and each with six curing periods (1, 3, 7, 28, 56, and 90 days).

5 illus, 6 tables, 30 ref

017583   Das A K;Dhal J P;Panda R K;Mishra S C;Sen S (Metallurgical & Material Engineering Dep, National Institute of Technology, Rourkela, Odisha, Email: jyoti84.chem@gmail.com) : Effect of alloying elements and processing parameters on mechanical properties of austempered ductile iron. J Mater metall Engng 2013, 3(1), 8-16.

In the present work, austempering is carried out for three different grades (Unalloyed, copper alloyed and Nickel alloyed) of ductile iron. After that the variation of mechanical properties (Hardness, Tensile strength and Elongation) and microstructure of the austempered ductile iron (ADI) with alloying elements (Copper and Nickel) and austempering process variables (austempering temperature and austempering time) were studied. It is found that, with increasing austempering time hardness, tensile strength and elongation are increasing but with increasing austempering temperature hardness and tensile strength are decreasing and elongation increasing. Austempered ductile iron with alloying element (Cu or Ni) is showing some improved mechanical properties such that: higher strength, hardness and lower elongation, than the unalloyed austempered ductile iron. In Microstructure, higher ferrite fraction is observed for higher austempering time and higher austenite fraction is observed for higher austempering temperature, for all the three grades of austempered ductile iron.

2 tables, 14 ref

017582   Chokprasombat K;Harding P;Sirisathitkul C; Muthitamongkol P;Pinitsoontorn S (Molecular Technology Research Unit, School of Science, Walailak University, Nakhon Si Thammarat, 80161, Email: schitnar@wu.ac.th) : Composition study of FePt nanoparticles synthesized from modified polyol process. Indian J Engng Mater Sci 2012, 19(5), 338-42.

Five different conditions for modified polyol processes using iron(III) acetylacetonate and platinum(II) acetylacetonate as starting materials reveal significantly different products in terms of composition. The initial Fe:Pt molar ratio is not retained in the final products and Pt-rich nanoparticles are obtained from 1:1 molar ratio of Fe:Pt sources. The imbalance between Fe and Pt indicate that the nanoparticles formation can be explained by the heterocoagulation mechanism rather than the binary nucleation model. The increase in refluxing time and initial Fe:Pt molar ratio improved the amount of Fe in nanoparticles. However, the highest molar ratio of 3:1 apparently affected the uniformity of particles. The co-existence of iron oxide and Pt-rich nanoparticles is clearly evident in the case of 3:1 molar ratio combined with 1,2 hexadecanediol as a reducing agent.

2 illus, 1 table, 16 ref

017581   Chakraverty A P;Mohanty U K;Ray B C (Metallurgical and Materials Engineering Dep, National Institute of Technology, Rourkela, Odisha, Email: apchakravarty@gmail.com) : Response of sea water immersed GFRP composite to thermal shock. J Mater metall Engng 2013, 3(1), 35-41.

Work involves examining the effects of sea water immersion and temperature fluctuations, precisely that of up and down thermal shocks (lower to higher and vice-versa), on the glass fiber /epoxy laminated composites. These effects are studied in terms of sea water absorption, degradation in inter laminar shear strength (ILSS), alternations in the glass transition temperature (Tg) as compared to the untreated samples and finally listing up of the mode of failure as established through scanning electron micrographs. The ingression of sea water is found to be anomalous, the rate of ingression picking up with time of immersion from an initial low value and then again slowing down with lapse of time. Shorter durations of exposure to up thermal shock exhibits an increasing trend in ILSS value while longer exposures do not affect the ILSS value much. The longest period of exposure to down-thermal shock causes a sharp decrease in the ILSS values. The Tg depression is more visible under up-thermal shock compared to that under down-thermal shock, the chief mode of failure being fiber pull out, fiber fragmentation and delamination.

9 illus, 2 tables, 26 ref

017580   Buvanashekaran G;Ganesh Kumar K (NO, Welding Research Institute, BHEL, Tiruchirappalli-620 014) : Study on tube positioning tolerances for magnetically implled arc but welding of thick walled tubes. WRI Jl 2011, 32(4), 12-22.

Magnetically Impelled Arc Butt (MIAB) welding is a solid state joining method predominantly used in automobile applications for joining of tubes and rods in Europe and Canada. In majority of the cases, tubes with less than 3mm wall thickness and surface area of joining between 150 to 400 sq.mm only are being used in the above industries. At WRI, experiments were conducted to study the MIAB welding technology for welding of high wall thickness tubes ranging from 4 to 6.5mm and having weld surface area of maximum 1100 sq.mm. In order to establish this welding process for joining of components for power plant industries, it is necessary to get the process approved by the competent authorities in this field of manufacturing. As a part of this work, experiments were carried out to study the positioning tolerances of the two tubes in the die, which are to be welded by MIAB process. Axial offset between tubes was varied from 0.25 to 2.00mm in steps of 0.25mm and the angular offset was varied from 1 to 5 deg in steps of 1. The results shows that axial offset upto 1.5mm passes tensile and bend tests, whereas 2.0mm axial offset resulted in failure in weld line with 20% reduction in UTS values. However, 2.0mm axial offset passes root and face bend tests. The angular offset up to 5 °C passes tensile and bend tests. Detailed microhardness and microstructural analysis were carried out for the select tolerance levels based on production constraint criteria. The results will provide a window of acceptance criteria for the input materials, i.e. tube positioning tolerance, axially and angularly on welding die, for obtaining an acceptable weld with satisfactory mechanical properties.

15 illus, 7 tables, 7 ref

017579   Altunisik A C;Bayraktar A;Sevim B (Civil Engineering Dep, Karadeniz Technical University, 61080, Trabron, Turkey, Email: ahmetcan8284@hotmail.com) : Operational modal analysis of a scaled bridge model using EFDD and SSI methods. Indian J Engng Mater Sci 2012, 19(5), 320-30.

In this study, dynamic characteristics of a laboratory bridge model are determined by operational modal analysis using frequency and time domain methods. For this purpose, a reinforced box girder concrete bridge model is constructed in laboratory conditions. The bridge deck consists of a main span of 3 m and two side span of 1.5 m each. The structural system of the model bridge consists of deck, piers and foundation. The total length of bridge deck is 6 m and width of bridge deck is 60 cm. Ambient vibration tests are conducted to the model bridge to identify its natural frequencies, mode shapes and damping ratios. Natural excitations such as wind and impact hammer are used to vibrate the model bridge. Vibration data is gathered from bridge deck. Measurement time, frequency span and effective mode number are determined by consider similar studies in literature. Sensitivity accelerometers are placed to collect signals from the measurements. The signals collected from the tests are processed by operational modal analysis; and the dynamic characteristics of the bridge model are estimated using enhanced frequency domain decomposition (EFDD) method in the frequency domain and stochastic subspace identification (SSI) method in the time domain. The dynamic characteristics obtained from both methods are found to be close to each other. Maximum 2.68% differences are obtained between natural frequencies for the first mode. Modal assurance criteria values are between 0.85-1.00. This shows that EFDD and SSI results are almost overlapped. It can be concluded that the both of enhanced frequency domain decomposition and stochastic subspace identification methods are very useful to identify the dynamic characteristics of the bridge model.

15 illus, 6 tables, 31 ref

017578   Ahmmad Z;Ansell M P;Smedley D;Tahir P M (NO, Institute of Infrastructure Engineering and Sustainable Management, Un, Malaysia, Email: zakiahah@hotmail.com) : Effect of environments on the thermal properties of epoxy adhesives modefied with nano- and micro-particles for in-situ timber bonding. Indian J Engng Mater Sci 2012, 19(5), 343-56.

This paper reports the investigation made on the effect of nano- and micro-particles additions on the thermal properties of epoxy based adhesives when exposed to different environmental conditions. The thermal behaviors of the adhesives are measured using dynamic mechanical thermal analysis (DMTA) following exposure to different temperatures and humidities which include temperatures of 20, 30 and 50°C, relative humidities of 65, 75 and 95% RH and soaking in water at 20°C and placed in the oven at 50°C. The dynamic thermal properties reported include storage modulus and loss modulus, the loss tangent and the glass transition temperature, Tg. For nano- and micro-particles filled adhesives, the glass transition temperature increases with increase in temperature even though the adhesives are subjected to high humidity and this is due to further cross-linking. The results show that room temperature cured epoxies are only partially cured at room temperature.

1 illus, 3 tables, 35 ref

017577   Ahmad A;Anil Kumar (Engg. Chemistry Dep, Al-Kabir Polytechnic, Mango, Jamshedpur, Email: rsakumar94@yahoo.co.in) : Review of nitrite inhibitor for protection of rebar corrosion. J Mater metall Engng 2013, 3(1), 42-56.

Load bearing concrete structures need steel reinforcement (rebar) strips or rods, which are prone to attack by the corrosive environment inside the concrete due to constant ingress of moisture, pollutant gases and anions (mainly Cl-, SO4- -). One of the means of reducing such type of corrosion is the use of inhibitors. Inhibitors are water soluble but film forming on metals by their selective adsorption on the metal surface. These may be inorganic or organic chemicals selected on the basis of their performance in inhibition but the nitrite inhibitors were suitable choice for protection of rebar corrosion.

^iia23 illus, 93 ref

017576   Aditya Nag M V (Mechanical Enigneering Dep, Gokaraju Rangaraju Institute of Engineering and Technology, Nizampet, Bachupally, Hyderabad, Email: kalaki@indiatimes.com) : Environmental value engineering analysis on performance optimization of an oil fired crucible furnace using oscillatory combustion technology. J Alternate Energy Sour Technol 2012, 3(2), 11-18.

Environmental Value Engineering Concept (E.V.E.) is a proven disciplined approach for improving measurable efficiency parameters for any organization or a system. In this paper, Overall Equipment Effectiveness (O.E.E.) for oil fired crucible furnace, which is a metric for Total Productive Maintenance initiative, has been calculated. As this performance was below the expectation level and resulting into outsourcing of jobs at higher cost, the E.V.E analysis was taken under consideration for overall performance improvement of the furnace. This paper deals with the application of E.V.E concept has been applied for process improvement considering O.E.E. as a parameter in the furnace system through the usage of Oscillatory Combustion Technology. Few modifications in the furnace set up were also carried out and are experimented the furnace at different scenarios. The outcome of this work was a visibly clean exhaust, optimized combustion efficiency which not only saves the environment but also a lot of expenditure on fuel consumption. Successful implementation of this concept has resulted to achieve the best performance of the furnace in a cost effective manner.

4 illus, 20 ref

016544   Venkatesh Kumar N;Jeelami M U;Shandilya A S (Electronics & Communication Engineering Dep, Jain Univ, Bangalore, Email: mujeebjeelami@yahoo.co.in) : Reducing crosstalk in arithmetic and logic unit part of a processor. J VLSI Des Tool Technol 2013, 3(1), 28-32.

Crosstalk is common in any digital systems and may occur due to coupling of signals which eventually have an impact on the working of a system. In this paper, an attempt is made to study the effect of crosstalk in 8-bit slice ALU, designed using 120 nm technology and suggested a method to reduce the crosstalk.

9 illus, 3 tables, 5 ref

016543   Upendira J (Aeronautical Engineering Dep, SNS College of Technology, Coimbatore, Tamilnadu, Email: Upendira.j@gmail.com) : Thermal modelling and simulation of brushless D.C. motor for electromechanical actuation. J Aerospace Engng Technol 2013, 3(1), 16-28.

Lumped-parameter thermal model is described which provides both a steady-state and transient solution to the temperatures within an electrical machine. The model is sufficiently complex to identify the temperatures at most locations in the machine, including the peak temperatures in the end winding and the surface temperatures of the rotor. It is formulated out of purely dimensional information and constant thermal coefficients and is therefore easily adapted to a range of frame sizes. The thermal behaviour of the machine is accurately described by the solution of just eight linear differential equations. The model is therefore suitable for application to online temperature estimation for protection and duty-cycle evaluation. The model performance is confirmed by experimental temperature test result. The simulation has been carried out using Simpower toolbox in Simulink.

13 illus, 2 tables, 14 ref

016542   Sivaramkrishnan;Prabhu S M (NO, Vinayaka Mission Univ, Chennai) : Electrical and thermal analysis of porous non-isothermal bed. J Metall Mater Sci 2012, 54(1), 63-75.

The problem of Mixed convection about a vertical flat plate embedded in a porous medium is analyzed. Nonsimilarity solutions are obtained for the cases of variable wall temperature (as a function of distance) and a variable surface heat flux (VHF) in form of q = w_{(x) = bxm}. This applies to all regions of convection,by two a nonsimilarity parameter from forced convection (χ* or = 1) to free convection (χ* or =0).

17 illus, 14 ref

016541   Seresinhe R;Lawson C (NO, Cranfield Univ, Cranfield UK, MK43 0AL, Email: r.w.seresinhe@cranfield.ac.uk) : MEA evolution in commercial aircraft and the consequences for initial aircraft design. J Aerospace Engng Technol 2013, 3(1), 1-15.

Important objective in commercial aircraft design is to develop a 'greener' aircraft. This objective poses many challenges in many fields of aircraft design. The push towards a more environment friendly, efficient and cost effective design has recognized the 'MEA (more-electric aircraft)' as a means to contribute towards realizing this goal. The more-electric aircraft can be thought of as an evolutionary concept where non-electrically powered systems and components are gradually replaced by competent electrical systems and components thus leading to an 'all-electric aircraft. This paper presents a critical review of a subset of commercial aircraft in terms of the secondary power systems, to form the trends and observe how the importance of electrical power in aircraft operation, has changed over the years. It presents electric load profiles for some conventional aircraft and discusses the parameters that affect the sizing of electrical power sources. It also highlights step changes in technology which had a significant effect on the sizing of power sources. The purpose of the review is to inform and improve the secondary power systems design at the early aircraft design stage, by developing a new methodology. The results presented here firstly show that the total electrical load in aircraft has increased steadily in the conventional configurations and show that there is a rapid increase in the MEA concepts and designs. It also reviews potential reasons for key characteristics identified in the analysis. Moreover, the review reaches the conclusion that an estimate of the generator rating based on conceptual parameters such as the aircraft mass, aircraft service entry year amongst others is not adequate and that a more robust methodology is needed to aid the design process.

9 illus, 1 table, 30 ref

016540   Samanta A;Ojha K;Mandal A;Sarkar A (Enhanced Oil Recovery Laboratory, Petroleum Engineering Dep, Indian School of Mines, Dhanbad, Email: mandal_ajay@hotmai.com) : Extraction and characterization of an eco-friendly surfactant for its use in enhanced oil recovery. J Petrol Engng Technol 2013, 3(1), 20-9.

Experimental studies have been performed to explore the suitability of an eco-friendly surfactant in enhanced oil recovery. In this respect, herbal surfactant has been isolated from soap nut and characterized by its morphology and physico-chemical properties. The extracted surfactant reduces the interfacial tension significantly over a wide range of concentrations. A series of flooding experiments have been carried out using the extracted surfactant and substantial incremental recoveries have been observed after the conventional water flooding. Use of alkali and polymer were found to improve the incremental recovery because of synergistic effects of surfactant, polymer and alkali.

16 illus, 1 table, 18 ref

016539   Saini A K;Agarwal M (NO, CSIR-Central Electronics Engineering Research Institute, Pilani) : New sub-1 volt reference for low voltage application based on MOSFET's threshold voltage extractor. J VLSI Des Tool Technol 2013, 3(1), 14-9.

CMOS voltage reference circuit featuring MOS transistors threshold voltage extractor has been developed. The circuit implemented using 0.35 μm CMOS AMS process generates a reference of 574 mV for a power supply of 3.3V with 726 μW power consumption. The circuit presents a variation of 43 ppm/°C for the -10 to - 110°C temperature, and 18.6 dB PSRR at 1 KHz. A vital analytical approach is presented to provide a universal design guideline.

12 illus, 2 tables, 10 ref

016538   Rajput K R;Singh S;Saini R;Saini A K (Semiconductor Bussiness Unit, Tata Elxsi India Pvt. Ltd., Oilani, Raj-333 031, Email: anilsaini.ceeri@gmail.com) : High performance reference circuit with optimized input offset operational amplifier using device mismatch model. J VLSI Des Tool Technol 2013, 3(1), 1-7.

In this paper, author describes a band gap reference (BGR) circuit, having reference voltage 1,20V with maximum temperature coefficient of 63 ppm/°C in temperature range of-40 to 120 °C. The circuit operates in range of supply voltage, 3.0V to 3.6V. An operational amplifier (op-amp), whose input offset voltage is reduced upto 892 μ V using Pelgrom 's device mismatch model is used in BGR. The power supply rejection ratio of circuit is improved at higher frequency and achieved 36 dB at 1 MHz. The circuit having area of 0.45 mm² in 0.35 μm CMOS technology is designed, fabricated and tested successfully.

11 illus, 2 tables, 16 ref

016537   Patel H;Menghani Jyoti (NO, S.V. National Institute of Technology, Surat-395 007, Email: hit2424@gmail.com) : Wear characteristic of unalloyed and alloyed LM25- aluminium casting. J Metall Mater Sci 2012, 54(2), 131-5.

Use of aluminium alloys is increasing in passenger cars and potential for further growth is large. Further increase will depend on the improvement in properties of material for existing application or finding new application. Alloys A-356(LM25) is being universally used for alloy wheel rims of luxury as well as for other types of cars. Globally 40% cars are running on aluminium alloy wheels. In this research 0.2% Cu has been added in ternary system of Al-Si-Mg alloy to increase mechanical properties of existing alloy. The alloy was cast in to metal mould and was solution treated at 540 for 4 hrs, water quenched and precipitation hardened for 12 hrs at 180°C. Wear characteristics of the material were observed under Wear testing using K93500 Pin-On-Disc Tester ASTM G99 test standard. This test was carried out under during dry condition using 2.5kg and 3.5 kg load, at 300 rpm of disc speed for 15 min. The microstructural characteristics of worn surface of alloys have been investigated using scanning electron microscopy_SEM. All intermetallic compound formed during solidification has been investigated through XRD.

16 illus, 6 ref