001807   Gopalakannan S;Senthilvelan T (Mechanical Engineering Dep, Adhiparasakthi Engineering College, Melmaruvathur, Tamil Nadu-603 319, Email: gopalakannans@yahoo.com) : Synthesis and characterisation of Al 7075 reinforced with SiC and B₄C nano particles fabricated by ultrasonic cavitation method. J scient ind Res 2015, 74(5), 281-5.

The application of ultrasonic effects to disperse nano sized particles in molten metal has been studied. Based on this technique, nano-sized SiC and B₄C particles reinforced with AL7075 aluminium nanocomposites were fabricated. XRD analysis reveals that uniform structure of nano composites was formed in the Al alloy. The microstructure of the nanocomposites was investigated by high resolution scanning electron microscope (SEM). Experimental results show a nearly uniform distribution and good dispersion of the SiC and B₄C nanoparticles within the aluminium metal matrix, although some small clusters were found in the matrix. The mechanical properties like tensile strength and micro hardness of nanocomposites have been improved significantly compared to that of pure alloy. The interaction between SiC and B₄C nanoparticles with aluminium matrix was investigated.

3 illus, 14 ref

001806   Dewan N;Aggarwal P;Vohra H (NO, , ) : Test time and power optimization of 2D SOCS using GA and greedy algorithm. J Pwr Elect Pwr Syst 2015, 5(2), 63-7.

Paper presents a genetic algorithm (GA) and greedy algorithm-based solution to co-optimize test scheduling under power constraint for core-based system-on-chips (SOCs). The core testing solutions are represented as set of wrapper configurations represented in rectangular bins of width equal to the test access mechanism (TAM) bandwidth and height equal to the corresponding test time. A best fit algorithm is used for the wrapper design. Experimental results are obtained for ITC'02 benchmark SOCs. The GA algorithm provides 8% reduction in testing time as compared to the greedy algorithm.

001805   Devi R B;Balaganesan S M (NO, , ) : Multiport bidirection DC-DC converter for hybrid energy storage systems. J Pwr Elect Pwr Syst 2015, 5(1), 9-13.

Multipart DC-DC converters are widely used in hybrid energy generation systems, microgrids and electric vehicles to provide stable power to key loads with high power density. In this project, a multipart isolated bidirectional DC-DC converter is anticipated for hybrid energy storage system in microgrids. Microgrids are connected to the nearby renewable energy generation systems as solar, wind, etc. These systems do not provide pure DC voltage for conversion into AC required by the grid. Hence a single stage DC-AC-DC conversion is required. For energy management and single-stage power conversion, multipart bidirectional converter (BDC) is the best choice. Also to minimize the switching losses and henceforth to improve the efficiency of the converter system, zero voltage switching (ZVS) can be achieved far all switches in any direction of power flow in the whole load range with decoupled duty cycle control and phase shift.

001804   Deole G S;Tambavekar A S;Baviskar V R;Sable S R;Chitale M M;Nimbalkar V M (NO, GV Acharya Institute of Engineering & Technology, Karjat-410 101) : Wear behavior of al-alloy (al-5mg) in-situ reinforced TiB₂ particulate. J Metall Mater Sci 2014, 56(4), 217-22.

Research has been carried out for replacing Al monolithic alloys by aluminium based metal matrix composites (MMCs) in many engineering applications where high wear resistance and stiffness are required. In this paper, the investigated dry sliding wear behavior of TiB₂ particulate reinforced composite of AI-Alloy (AI-5Mg) is discussed. The in situ AI-Alloy (AI-5Mg) 10wt% TiB₂ composite material were been prepared by molten flux reaction synthesis using electric melting furnace. Dry sliding wear behavior of composites was estimated by pin on disc method and wear data is linked with SEM studies. The end result showed that the wear resistance of cast AI-Alloy (AI-5Mg) can improved further by fine size TiB₂ particulate reinforcement formed in in-situ during reaction synthesis and have moral bonding with matrix.

001803   Chakraverty M;Gupta K;Babu V G;Meshram V M (NO, , ) : Technological review on quantum ballistic transport model based silicon nanowire field effect transistors for circuit simulation and design. J Nanosci Nanoengng Applic 2015, 5(2), 20-31.

Nanowire MOSFETs are recognized as one of the most promising candidates to extend Moore's law into nanoelectronics era. This paper reviews the process, application, device physics and compact modeling of Gate All around (GAA) nanowire MOSFETs. The most widely used methods of nanowire synthesis have been discussed. The paper presents the various device optimization techniques and scaling potential of nanowire transistors. A process sensitivity study of silicon nanowire transistors at the end of the paper justifies the theory of nanowire FETs to carryforward the downscaling of MOSFETs in the sub-10 nm regime.

001802   Bhattacharyya S K;Agarwal A K (NO, CSIR-Central Building Research Institute, Roorkee-247 667, Email: director@cbri.res.in) : CSIR-central building research institute, Roorkee. Curr Sci 2015, 108(8), 1444-53.

CSIR-Central Building Research Institute, Roorkee has been vested with the responsibility of generating, cultivating and promoting building science and technology in the service of the country. Since its inception in 1947, the Institute has been assisting the building construction and building material industries in finding timely, appropriate and economical solutions to the problems of building materials, health monitoring and rehabilitation of structures, disaster mitigation, fire safety, energy efficient rural and urban housing. The Institute is committed to serve the people through R&D in the development process and implementation of innovative housing programmes.

12 illus, 2 tables

001801   Bhaduri S;Sharma A;Talat N (Centre for Studies in Science Policy, School of Social Sciences, Jawaharlal Nehru Univ, New Delhi-110 067, Email: saradindu@jnu.ac.in) : Growth of water purification technologies in the era of 'regulatory vacuum' in India. Curr Sci 2015, 108(8), 1421-23.

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001800   Asodariya J D;Pandya V (NO, , ) : Brief review on single phase PV micro-inverter system. J Pwr Elect Pwr Syst 2015, 5(2), 55-62.

This paper presents a review on recent developments and a summary of inverter technology for single phase grid-connected photovoltaic (PV) systems for power levels up to 5 kW. The functions of inverter include DC-AC conversion, output power quality assurance, various protection mechanisms, and system controls. PV inverters are classified in three categories which are centralized inverter, string inverter and module oriented or micro inverter. Centralized inverter, string inverter and module oriented/integrated inverters are discussed as they are widely used in industrial applications. Based on discussion about these PV inverters, the limitation of centralized and string inverter came out. Centralized inverters have very large central inverter which also includes the large numbers of PV panels joined into series. This structure will produce high voltage. String is made up of PV modules by connecting them in series. Output of the string is then given to an inverter. Overall efficiency is improved compared to centralized inverter method and also there is reduction in size. In module oriented inverter/micro inverter, every solar panel unit has its private inverter. The integration of inverter and solar panel significantly decreases installation costs. It also maximizes the solar energy harvesting and improves safety. When some part of solar panel is covered by shadow of pole, tree etc. then centralized and string inverters can V work. Micro inverter is cost efficient and effective solution when some panel is partially covered by shadow of tree, poles or tall building. Micro inverter is the best inverter topologies for solar P V module.

001799   Anu N;Nandagopal M S G;Aneesh V;Selvaraju N (Chemical Engineering Dep, National Institute of Technology, Calicut, Kozhikode-673 601, Email: selvaraju@nitc.ac.in) : Coupled receptor-dispersion model evaluation for the assessment of area source emission rate. J scient ind Res 2015, 74(5), 296-301.

Atmospheric pollution is a major disaster in the current century. The geometry of pollutants emission from various sources has been categorised as point, area and volume. Particulate matters (PM₁₀ & PM_2.5), gaseous pollutants and volatile organic carbons (VOCs) are the significant pollutants from various source types due to natural as well as anthropogenic activities. These pollutants once entered into the atmosphere get transport due to the meteorological aspects and other reasons. Hence the cause effect of these significant species may adversely generate negative impacts on the environment called receptors. The current research work focused on the prediction of emission rate (Q, unit/sec) from an area source through a combined receptor-dispersion (shear) model analysis. The Shear model coupled with chemical mass balance receptor model will produce better emission rate estimation from an area source such as agricultural land. For this vertical mixing height (z) in the dispersion model has been considered as 2 m and the area has been divided to 100 strips of width 10 m. Shear model predicts the concentration of pollutants which is emitted from an area source. Chemical mass balance model can estimate the contribution of these sources at far distance say 1000 m from the source of emission. The results obtained from these distinct approaches have been cordially assessed for refining dispersion model parameter such as emission rate (Q, unit/sec) using coupled receptor-dispersion (area source) model. The observation was adequate for error in the emission rate increases as receptor concentration varies for 20%, 40%, 60% and 80% in both objective functions J₃ and J₄ considered. The results obtained were clearly suggests the individuals to make use of the coupled model approach for a better pollutant emission management at the location.

3 illus, 3 tables, 25 ref

001798   Agnihotri R;Kumar R;Prasad M V S N;Sharma C; Bhatia S K;Arya B C (Radio and Atmospheric Science Div, CSIR-National Physical Laboratory, New Delhi-110 012, Email: agnir@uplindia.org) : Experimental setup and standardization of a continuous flow stable isotope mass spectrometer for measuring stable isotopes of carbon, nitrogen and sulfur in environmental samples. MAPAN 2014, 29(3), 195-205.

This is a presentation of an experimental setup and standardization of a newly acquired stable isotope ratio mass-spectrometer (Isoprime 100, Isoprime^{® UK) coupled with elemental analyzer (Pyrocube, Elementar®-Germany) in a continuous flow mode, for the measurements of C, N and S isotopes in a variety of natural as well as synthetic organics and sulfur containing solid samples. We have calibrated our instrument using a suite of certified international standards supplied by International Atomic Energy Agency Vienna and cross-checked against several in-house laboratory standards used by other institutions of international repute. A synthetic organic compound Sulfanilamide was continuously used along with international standards to develop an in-house internal laboratory standard for the accurate and precise isotopic measurements. Important components contributing to the overall uncertainty of the isotopic measurements such as blank contributions, amount effect and response of mass-spectrometric current against thermal conductivity detector were performed using several aliquots of ε-Amino-n-caproic acid and sulfanilamide (in-house) standards. Both short and long term variabilities in the measure isotopic data were assessed using our in-house laboratory standard Sulfanilamide. Overall estimated uncertainties of C, N and S isotopic measurements are better than 0.2, 0.2 and 0.3% respectively; which are well within the recommended limits of aforementioned isotopic data.}

10 illus, 26 ref

001797   Adediji A T;Ajewole M O;Ojo J S;Ashidi A G; Ismail M;Mandeep J S (Physics Dep, Federal Univ of Technology, Akure, Nigeria, Email: kunleadediji2002@yahoo.co.uk) : Influence of some meteorological factors on tropospheric radio refractivity over a tropical locatiion in Nigeria. Mausam 2015, 66(1), 123-8.

Radio refractivity is computed from the measurements of atmospheric pressure, temperature and relative humidity made in Akure (7.15° N, 5.12° E), Nigeria using Davies 6162 wireless vantage Pro2 Weather Stations (Integrated Sensor Suite, ISS). Measurements are taken at five different levels starting from the ground surface to 200 m altitude at intervals of 50 m. Five years of data (January 2007 - December 2011) were utilised for the study. Results show that at all the levels, water vapour pressure has the most significant influence on radio refractivity. Temperature also influences refractivity as high values of refractive index are recorded in the transition months of November and Harmattan period of December/January that are usually associated with high air humidity arid low water vapour content. Pressure has the least influence, since significant changes in the measured value of pressure often correspond to minimal changes in value of radio refractivity.

15 illus, 20 ref

001796   Abhiram J S;Pernabas N;Inayath Pasha I;Khan S;Anand A;Johns J (NO, , ) : Fully interpenetrating polymer network from natural rubber and guar gum. J Mater metall Engng 2015, 5(2), 18-21.

Fully interpenetrating polymer network (IPN) based on natural rubber (NR) and guar gum (GG) was prepared by using glutaraldehyde as a common crosslinking agent. As both the polymers are naturally occurring and the resulting IPN material can be termed as a green polymeric material. The solvent resistance properties of these samples were investigated by equilibrium swelling method using benzene as a solvent. Benzene was used as the penetrant for the transport studies through fully IPN system The aim of this study is to find the applicability of such polymers for the preparation of fuel lanes with excellent properties. Samples were prepared with different weight fractions of natural rubber and guar gum For the composition NR99.5GG0.5, samples were prepared with various amount of glutaraldehyde. Solvent uptake with time has been measured for different IPN samples. A reduction in solvent uptake was observed with increase in the percentage of GG in natural rubber. The impact of the amount of glutaraldehyde on the solvent transport of the system was also analyzed. A reduction in swelling was exhibited with the addition of glutaraldehyde to the natural rubber/guar gum by the formation of IPN.

001795   Aafrin S;Annam M (NO, , ) : Torque ripple reduction in induction motor drive using direct torque control technique with space vector modulation. J Pwr Elect Pwr Syst 2015, 5(1), 33-9.

Three phase squirrel cage induction motor drives are widely used in industries for variable speed applications. This paper proposes the design and simulation of an induction motor (IM) drive with DTC-SVM (Direct Torque Control-Space Vector Modulation). The IGBT/Diode inverter switches are controlled by the DTC-SVM technique. The synthesis of vector selection table depends on the rotational direction of the stator flux vector. The control algorithm in DTC-SVM methods are based on averaged values whereas the switching signals for the inverter are calculated by space vector modulator. The performance of this method is demonstrated by simulation using Matlab/Simulink software package and a comparative study with conventional DTC and Field Oriented Control (FOC) is performed.

000775   Verma S K;Lal R;Raman Kumar (Civil Engineering Dep, PEC Univ of Technology, Chandigarh-160 012, Email: skverma5724@yahoo.com) : Seismic response of RC framed buildings. Int J civ struct Engng 2014, 4(4), 499-506.

In the present study the structural behaviour of the buildings with shear walls at different locations has been investigated and compared in terms of storey drift and average displacement. For this purpose two Reinforced Concrete framed regular buildings with different locations of shear walls situated in seismic zone V have been investigated. Ten-storeyed and Fifteen-storeyed buildings were taken with four different locations of shearwalls i.e. at central frame, external frame, internal frame and combined external and internal frames. These buildings were analyzed using commercially available software STAAD PRO by Seismic Coefficient Method and the seismic response of the building was compared in terms of storey drift and average displacement. It has been observed that with the incorporation of shear walls storey drift and average displacement decrease considerably. It was noticed that for the buildings investigated in the present study, the shear walls located at internal frames are most effective in reducing the storey drift and average displacements.

000774   Veerubhotla A;Kumar S;Bachhal S;Kumar A (Biomedical Instrumentation Div, CSIR-Central Scientific Instruments Organisation, Chandigarh, Email: virdi205@gmail.com) : Mobility assistance for patients with quadriplegia. J scient ind Res 2015, 74(2), 100-4.

Immobility often causes psychological and social effects on the person. Since immobility cannot be cured even by using drugs in most cases, it is essential that such people be given a means of mobility which does not let their immobility hinder their day to day life. This paper describes a very feasible mobility solution for the physically impaired people especially those who are suffering from spinal cord injury in the higher levels of C1-C7. Independent Electromyogram( EMG) signals obtained from the neck muscles of the patient using active EMG electrodes have been used to control the direction of movement of the wheelchair. The direction and degree of movement of the neck governs the speed and motion of the motor powered wheelchair. Ultrasonic sensors placed on the wheelchair have been used for obstacle avoidance. Experimental results have shown that the designed solution is very feasible, cost effective and requires very less training of the user.

2 illus, 7 ref

000773   Vakil Merool D;Shah J U;Patel H S (Applied Mechanics Dep, Government Engineering College, Patan, Gujarat) : Numerical study on deformation characteristics of composite slab - with and without embossments. Int J civ struct Engng 2014, 4(4), 477-82.

Many efforts have been made by the researchers to forecast the strength of composite slab experimentally. The experimental methods based on the full-size test are expensive, time consuming and semi-empirical. This paper describes a study on finite element modelling of composite slab numerically. The aim is to understand the deflection characteristics of steel-concrete composite deck in order to improve designs for steel decking for composite slabs. 3-D finite element slab model is built, with and without embossments on profile deck. Analysis is carried out on simply supported composite slab under two point line loads by varying parameters: concrete height and concrete grade. It has been observed that composite slab without embossment deformed more as compared to slab with embossment.

000772   Tandel Y;Jamal M;Solanki C;Desai A (NO, GIDC Degree Engineering College, Navsari-396 439, Email: tandel.yogendra@gmail.com) : Numerical analyses of laboratory- modelled reinforced stone column. Curr Sci 2015, 108(7), 1354-62.

Stone column develops its vertical load carrying capacity by the lateral pressure provided by the surrounding soil. In very soft clay (C_u ≤ 15 kPa), the stone column may not derive its load carrying capacity. Sometimes the formation of stone column is doubtful. In such cases, the stone column may be wrapped with geosynthetic peripherally (circumferentially). Normally, reinforced stone columns are used for widely spread areas like air tank foundation and embankment in which they confined by surrounding the columns. The performance of a small group of reinforced stone columns is complex. This communication focuses on the numerical modelling of a small group of laboratory-modelled reinforced stone columns. The study is carried out considering parameters like area replacement ratio (ARR), stiffness of reinforcement material and reinforcement length. The performance of reinforced stone column group is discussed in terms of bearing ratio, (q/C_u)-settlement ratio, stress concentration factor and lateral deformation. The results of numerical analyses indicate that ARR and stiffness of geosynthetic are the governing parameters for enhancing the performance of reinforced stone column. The performance of partial reinforced stone column is close to that of a fully reinforced stone column.

17 illus, 2 tables, 23 ref

000771   Taghreed A;Mohammed K (Geotechnical Dep, Engineering Faculty, Koya Univ, Iraq, Email: taghreed.khaleefa@koyauniversity.org) : Flexural behavior of reinforced beams reinforced with corrosive rebar. Int J civ struct Engng 2014, 5(1), 64-73.

In this paper, the effect of pre corrosion of rebars on the flexural behavior of reinforced concrete beams was investigated. The corrosion was induced at rebar artificially, before using them as reinforcement, by using two methods. In the first method, the rebar were put in water with 8Δ salt concentration inside the lab. In the second method, the rebars were surrounded by salt outside the lab and left them free to effect of weather changing, like rain and different relative humidity. The second method was given more corrosion rate compared to the first method. Beams were tested in the ages of 30, 90 and 120 days. Two sizes of rebars (10 mm and 12 mm) subjected to corrosion were used. Test results indicate that high corroded rebar of 10mm diameter were carried higher load capacity with maximum deflection at mid span for all ages. The percentage of increasing load for this corrosion bar was found to be 144.3Δ, 141.7Δ, 124.3Δ for 30 days, 90 days and 120 days, respectively, compared with those beams contain lower corroded bars of same size. The percentages were 126.1Δ, 127Δ for 30 days and 120 days, respectively, compared with no corrosion of same bar size.

000770   Sil A;Dey A K (Civil Engineering Dep, NIT Silchar, Assam, Email: silarjun@gmail.com) : Dynamic performance of cohesive slope under seismic loading. Int J civ struct Engng 2014, 5(1), 1-14.

Main purpose of this study is to design and analyze a cohesive slope under dynamic loading condition and examine the relations between different parameters such as slope geometry, yield acceleration, and displacement. For estimating the permanent slope displacement, a code has been developed and yield acceleration was evaluated for different slope angles with varying cohesion. The code can be used to find out the critical slip circle of a cohesive embankment. It is possible to find out the displacement of cohesive embankment due to a ground motion using Newark method. However, in this study it has been observed that the permanent slope displacement decreases with the increase in yield acceleration and vice versa. Further, yield acceleration increases for higher cohesion property of materials. Another important observation is that, the yield acceleration shows a higher value at a lower slope angle. The estimated yield acceleration was compared with the Newmark's equation and found a good agreement with the present results. This study would attract the researchers and field engineers to know the dynamic behaviour of cohesive materials for its effective and wide engineering application.

000769   Shanmugavalli K R;Vedamuthu R (Architecture Dep, School of Architecture and Planning, Anna Univ, Chennai-600 025, Email: vallipre@gmail.com) : Viability of solar rooftop photovoltaic systems in grouphousing schemes. Curr Sci 2015, 108(6), 1080-5.

With conventional energy sources being limited in their availability, the search for alternative renewable energy sources is inevitable. Solar energy, an inexhaustible renewable energy is considered a vital source for a developing country like India, where there is a major deficit between the demand and supply of electricity. Crowded urban structures have all the updated electrical appliances, but there is a deficit power supply during peak hour demand. In a tropical country like India, airconditioning for cooling has become the norm during daytime due to IT facilities and allied support services. The Sun shines for 8-9 h during daytime, which coincide with the time of peak energy demand. The crowded rooftop of cities can be converted to solar electricity generators through rooftop photovoltaic systems. We have done a field study of the energy consumption of post-occupancy medium-rise (G + 4) group housing and high-rise (G + 10) group housing schemes in two different cities in India. The feasibility study for solar photovoltaic systems, along with the scrutiny of various schemes that are available to the building owners are discussed for post-occupancy owners as well as yet-to-be owners of such group development schemes.

12 illus, 14 ref

000768   Sangoju B;Bharatkumar B H;Gettu R;Srinivasan P;Ramanjaneyulu K;Iyer N R (NO, CSIR-Structural Engineering Research Centre, Chennai, Email: bhaskar@serc.res.in) : Influence of PCE-SP and calcium nitrite inhibitor on mechanical and durability parameters of concrete. J scient ind Res 2015, 74(2), 82-7.

This paper presents the results on the effect of polycarboxylic ether superplasticizer (PCE-SP) and calcium nitrite based corrosion inhibitor on the mechanical and durability parameters of concrete. Effect of water to cement ratio (w/c) as well as the type of cement, namely, ordinary portland cement (OPC) and fly ash based portland pozolana cement (PPC) was also studied. The studies reveal that the compressive strengths of OPC and PPC concretes with PCE-SP are found to be similar to that of their respective control concretes (OPC and PPC concrete alone). Nevertheless, the durability parameters such as rapid chloride penetration test (RCPT) value and sorptivity were improved. Hence, the use of PCE-SP must be encouraged for making durable concrete. When calcium nitrite inhibitor (CNI) is added to the concrete, a reduction in compressive strength was noticed. Also, there was an increase in the RCPT values compared to that of control concrete. This may be due to high ionic nature of CNI, which causes more negative charges to pass through concrete. Based on the study, it can be said that CNI influences the mechanical and durability properties and hence can be used with proper care.

4 illus, 30 ref

000767   Sangita M S (Saraswati College of Engineering, Mumbai Univ, Sector-5, Kharghar-410 210, Email: dr.sushreemishra80@gmail.com) : Rainfall analysis and design of water harvesting structure in water scarce Himalayan hilly regions. Int J civ struct Engng 2014, 5(1), 29-41.

Irregular rainfall pattern and high surface runoff are the main reasons of water scarcity and subsequent drought conditions in Himalayan hilly regions. Hence in this study, an attempt was made to assess the water scarcity in these regions through rainfall and runoff analysis. The Henval watershed, covering an area of 6608 ha (66.08 km^{2) and lies between 78° 15' to 78° 25' E longitude and 30° 20' to 30° 30' N latitude at an elevation that varies from 1200 to 2760 m above (MSL) was taken up for this study. The rainfall in the study area starts during May and lasts upto November. It was noticed that the uniformity of rainfall was pronounced from 23rd to 37th week (4th June to 10th September), whereas during the other weeks rainfall distribution was poor and erratic. Analysis of surface runoff by SCS CN model indicated that a considerable portion of precipitation flows off the watershed as runoff resulting in water scarcity and the main reason of agricultural drought in the watershed. Hence, there is a great need of storage of the water from runoff for future needs to avoid drought. Farm ponds can be used for storing water during rainy season as in hilly watersheds, they are found to be economical. As the study area is rainfed, a number of farm ponds can be constructed in higher order drainage networks of the area for water storage.}

000766   Roy S;Dass G (Civil Engineering Dep, Jan Nayak Ch. Devi Lal Memorial College of Engineering, Haryana, Email: surendraroydhn@yahoo.com) : Statistical models for the prediction of shear strength parameters at Sirsa, India. Int J civ struct Engng 2014, 4(4), 483-98.

Shear strength is the principal engineering property of soil, which controls the stability of a soil mass under structural loads. Therefore, it is always required to measure before design of foundation of any structure. In this study, a detailed survey was carried out within a 5 km radius of Sirsa and 10 locations were identified for soil sampling. The soil samples were collected at 50 cm depth from ground surface and analysed for different geotechnical properties like bulk density, dry density, natural moisture content, specific gravity, particle size, liquid limit, plastic limit, plasticity index and shear strength parameters (cohesion and angle of shearing resistance). With the help of particle size distribution curves, coefficient of uniformity and coefficient of curvature were evaluated to find out the gradation of particles. Influence of the geotechnical properties on shear strength parameters was studied. Stepwise regression procedure was carried out for the selection of most influencing variables. Incorporating selected variables, multiple regression models were developed for the prediction of shear strength parameters. The performance of the multiple regression models were assessed in terms of correlation coefficient, F-statistics and residuals pattern. Using the developed models, shear strength parameters can be computed for the study area.

000765   Rao A S;Rao G A (NO, RSR Engineering College, Kadanuthala, Kavali-524 142, Email: prof.asrao@gmail.com) : Comparison of mode I and mode II fracture energies of latex modified steel fiber reinforced concrete. Int J civ struct Engng 2014, 5(1), 53-63.

This paper presents the results of an experimental investigation which assesses the effect of Latex on fracture of steel fiber reinforced concrete under Mode I and Mode II loadings. Tests have been conducted on new notched beam specimens under pure shear. The test specimens made from concretes in which 10% of SBR latex dispersion on cement mass was added, were used in addition to plain steel fiber reinforced concrete specimens. The shear fracture energy, and flexure facture energy were calculated and an attempt has been made to know the ratio of Mode II to Mode I fracture energy. With the addition of latex, increase in the values of mechanical and fracture properties was observed.

000764   Rajaambal S;Sivaranjani K;Gopinath C S (Catalysis Div, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune-411 008, Email: cs.gopinath@ncl.res.in) : Recent developments in solar H₂ generation from water splitting. J chem Sci 2015, 127(1), 33-47.

Hydrogen production from water and sunlight through photocatalysis could become one of the channels, in the not-so-distant future, to meet a part of ever growing energy demands. However, accomplishing solar water splitting through semiconductor paniculate photocatalysis seems to be the 'Holy Grail' problem of science. In the present mini-review, some of the critical strategies of semiconductor photocatalysis are focused with the aim of enumerating underlying critical factors such as visible light harvesting, charge carrier separation, conduction and their utilization that determine the quantum efficiency. We attempted to bring out the essential requirements expected in a material for facile water splitting by explaining important and new designs contributed in the last decade. The newly emerged designs in semiconductor architecture employing nanoscience towards meeting the critical factors of facile photocatalysis are elucidated. The importance of band gap engineering is emphasized to utilize potential wide band gap semiconductors. Assistance of metal nanostructures and quantum dots to semiconductors attains vital importance as they are exuberant visible light harvesters and charge carrier amplifiers. Benevolent use of quantum dots in solar water splitting and photoelec-trochemical water splitting provides scope to revolutionize the quantum efficiency by its multiple exciton generation features. A list of drawbacks and issues that hamper the much needed breakthrough in photocatalysis of water splitting is provided to invite attention to address them and move towards sustainable water splitting.

1 illus, 13 tables, 75 ref

000763   Ouellette N T (Mechanical Engineering and Materials Science Dep, Yale Univ, New Haven, CT 06520, USA, Email: nicholas.ouellette@yale.edu) : Empirical questions for collective-behaviour modelling. Pramana J Phys 2015, 84(3), 353-63.

The collective behaviour of groups of social animals has been an active topic of study across many disciplines, and has a long history of modelling. Classical models have been successful in capturing the large-scale patterns formed by animal aggregations, but fare less well in accounting for details, particularly for groups that do not display net motion. Inspired by recent measurements of swarming insects, which are not well described by the classical modelling paradigm, I pose a set of questions that must be answered by any collective-behaviour model. By explicitly stating the choices made in response to each of these questions, models can be more easily categorized and compared, and their expected range of validity can be clarified.

54 ref

000762   Onwukwe S I;Ogbuagu C I;Obah B (NO, , ) : Review of radial drilling technology and viable prospect in mature field development in the Niger delta. J Petrol Engng Technol 2015, 5(2), 60-6.

A review of some Niger Delta oil field reservoirs indicates that most of the reservoirs are at the mature stages, thereby vulnerable to challenges such as; coning due to reduced size of the oil column, low oil production and lack of access to the residual oil trapped between existing wells of the mature field. Due to coning occurrences in the Niger-Delta oil field, most wells have been shut-in and a lot of recompletions are being made in order to combat this problem. To proffer solutions to these technical challenges of mature oil field, this study seeks to review the potentials of Radial Drilling Technology and its viable application to optimising oil production from mature oil field. Radial Drilling Technology involves a method and apparatus for milling through the walls of a well casing at a 90o angle to provide horizontally jetted radials of few inches diameter into the formation strata to a maximum of 330 ft. from the vertically extending well casing. The technology uses a combination of coil tubing operations, with milling bit and high pressure jet drilling assembly. Radial Drilling unlike the conventional drilling can get past the near well-bore well dam-age zone, allowing contact to the un-accessed part of the formation, thereby having potential to mop up oil from previously un-accessible zone with respect to optimising production from mature oil field.

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000761   Mondal S;Mukhopadhyay A;Sen S (Mechanical Engineering Dep, Jadavpur Univ, Kolkata-700 032, Email: achintya.mukho@gmail.com) : Non-linear dynamics in pulse combustor. Pramana J Phys 2015, 84(3), 443-53.

The state of the art of non-linear dynamics applied to pulse combustor theoretically and experimentally is reviewed. Pulse combustors are a class of air-breathing engines in which pulsations in combustion are utilized to improve the performance. As no analytical solution can be obtained for most of the nonlinear systems, the whole set of solutions can be investigated with the help of dynamical system theory. Many studies have been carried out on pulse combustors whose dynamics include limit cycle behaviour, Hopf bifurcation and period-doubling bifurcation. The dynamic signature has also been used for early prediction of extinction.

^iia7 illus, 20 ref

000760   Mondal A K;Bansal K (Electronics and Instrumentation Dep, Petroleum and Energy Studies, Dehradun-248 007, Email: akmondal1603@gmail.com) : Structural analysis of solar panel cleaning robotic arm. Curr Sci 2015, 108(6), 1047-52.

The efficiency of solar photovoltaic (SPV) panels depends upon the amount of solar irradiance and spectral content. SPV panels are being widely used because of their economic and environmental merits. The performance of SPV panels gets degraded due to factors like air pollution, bird droppings, dust, snow accumulation, etc. An automatic and integrated solar panel cleaning robotic arm (SPCRA) with four-degrees of freedom has been designed to overcome the above factors. The arm has two prismatic and two revolute joints. SPCRA has a unique end effector with a water sprinkler, air blower and a wiper installed as a single unit on it. Few traits like anti-interloped design, automated grid cleaning mechanism, efficient algorithm, all-weather cleaning support, and plug-n-play strategy with optimum costs make it a versatile system for cleaning the SPV panels.

4 illus, 7 tables, 42 ref

000759   Mahil J;Sree Renga Raja T;Sree Sharmila T (Electrical and Electronics Engineering Dep, Udaya School of Engineering, Vellamodi, Tamil Nadu, Email: mahilanto@yahoo.co.in) : Optimization algorithms for adaptive filtering of interferences in corrupted signal. Indian J pure appl Phys 2015, 53(4), 274-81.

Neural network adaptive filters are mainly used for the interference cancellation techniques. The gradient based design methods are well developed for the design of neural network adaptive filter but they converge to local minima. This paper describes the global optimization interference cancelling techniques for adaptive filtering of interferences in the corrupted signal. The system is designed using the adaptive filtering of the interferences in the corrupted signal using the Back Propagation Neural Network (BPNN) algorithm, Genetic Algorithm (GA), and Bee Colony (BC) algorithm. These optimization algorithms are used for initialization of weights, learning parameters, activation function and selection of network structure of the artificial neural network. The adaptive filtering system is designed using an adaptive learning ability of BPNN algorithm. This paper presents a comparison of evolutionary optimization algorithm such as hybrid GA-BPNN and BC-BPNN algorithm for the interference cancellation in corrupted signals.

12 illus, 2 tables, 16 ref

000758   Kishore T S;Singal S K (NO, Alternate Hydro Energy Centre, IIT Roorkee, Roorkee-247 667, Email: srinivasakishoret@gmail.com) : Design considerations and performance evaluation of EHV transmission lines in India. J scient ind Res 2015, 74(2), 117-22.

Increasing energy demand worldwide needs the development and strengthening of high voltage and high power intensity power transmission lines for meeting the energy requirements. Extra and ultra high voltage transmission lines have been developed and being operated successfully in the developed nations. Recent trends in Indian transmission scenario are progressing towards establishing extra and ultra high voltage lines to strengthen its transmission infrastructure. In the present study, an attempt has been made to discuss broad design aspects of extra high voltage lines. Performance analysis for evaluation of the benefits and costs resulting from these lines in power transmission has also been presented.

1 illus, 3 tables, 5 ref

000757   Katuri S R;Seepana M M (NO, , ) : Heat integration of crude organic distillation unit using aspen pinch. J Petrol Engng Technol 2015, 5(2), 35-46.

Recently, pinch analysis is proven as suitable methodology to optimize energy costs in chemical and petrochemical plants. In this article, the heat integration of crude organic distillation unit was elucidated with pinch analysis and ASPEN pinch simulating tool. Minimum utilities are calculated by constructing composite curves, shifted composite curves, grand composite curves and using problem table algorithm. Simulation studies include the effect of ΔT_min on hot and cold utilities requirement. Further Exergy losses are calculated by constructing Carnot composite curves and Carnot grand composite curves.

000756   Joshi B M R R (NO, , ) : Process scheme for effluent treatment for reinjection of produced water. J Petrol Engng Technol 2015, 5(2), 49-52.

Scope of the study is to conceptualize a treatment process for produced water treatment and reinjection into reservoir for pressure support. ABC field is producing 800 m^{3/day, with 60% water cut. To access the suitability of using effluent water for reinjection in ABC field, produced water analysis and treated water parameters have been considered for conceptualizing the treatment design. Produced water analysis reveals its inferior quality in terms of total suspended solids, oil content and high turbidity [1]. For achieving the treated water parameter for injection, suitable treatment process comprising of following facilities have been considered. This includes, storage tanks, corrugated plate interceptors (CPI), induced gas flotation (IGF), walnut shell filtration, chemical dosing, gas blanketing, injection facilities and sludge handling. Treated facilities are expected to make produced water suitable for reinjection in ABC field and address environmental issues associated with its disposal.}

000755   Hossain M;Hossain T R (Civil Engineering and Construction Dep, Bradley Univ, Peoria, Illinois, USA, Email: mihossain@fsmail.bradley.edu) : Column slenderness computation and evaluation using finite element method and commercial software. Int J civ struct Engng 2014, 5(1), 15-28.

In this study slender column was analyzed and evaluated using the Finite Element Method (FEM) modeling software ETABS and well-known commercial software PCACOL. First the slender column design methods described in ACI code were reviewed manually for one structural model. Then a manual calculation of the slender column design procedure was checked with ETABS. The ETABS result output was also verified with PCACOL. It was observed that ETABS was more conservative than PCACOL for determining Non-sway Moment Magnification Factor (dns). However, PCACOL was more conservative than ETABS for determining Sway Moment Magnification Factor (ds) value. Considering the non-sway column, the steel ratio is 9.22% greater in ETABS design output than PCACOL design output. PCACOL and ETABS used two different approaches to calculate dns as described or required by code. On the other hand, considering sway column, the steel ratio found in PCACOL was 79.60% higher than ETABS. ETABS performed P-Δ analysis approach but PCACOL used a code specified approach to calculate ds. Considering the different approaches followed by different structural analysis and design software, a designer should take care when using either software.

000754   Goswami R;Lahkar N;Talukdar P (NO, , ) : Design and layout modifications of an oil and gas processing facility in a part of the upper Assam basin, India. J Petrol Engng Technol 2015, 5(2), 15-20.

Oil and gas processing acts as the preliminary treatment required to be performed on the raw crude oil and gas obtained from the wells so as to make it fit for further processing in the refinery. A particular oil and gas processing facility, located in the Assam Arakan basin is chosen and a detailed study is carried out regarding its various aspects. The study shows that the processing facility has certain problems related to its design and layout which affects the entire crude processing operation. This paper aims at finding solutions to all these problems and suggesting a new layout in a manner that is both technologically and economically feasible. This technology can also be applied to analogous field processing stations in different parts of the world which have reservoirs having similar characteristics to upper Assam basin and also having crude with similar PVT properties.

000753   Geddam C;Somasundaram C;Joshi S (NO, , ) : Flexibility analysis of refinery piping system. J Petrol Engng Technol 2015, 5(2), 53-9.

Piping systems in downstream refineries and process plants experience a great thermal strain due to the difference between ambient and operating temperatures of process and utility fluid flowing through them. This thermal growth causes thermal stresses which leads to failure in piping components like flange leakage, deflection in piping, fractures at nozzle juncture and other fatal errors in piping system. Therefore, these piping structures must be flexible enough to support their own weight and to absorb thermal growth developed. To ensure this, a static flexiblility analysis will be performed by using an engineering tool called CAESAR II (Computer Aided Engineering Stress Analysis and Routing). Stress analysis ensures the flexibility in critical piping systems by maintaining the stresses below the allowable limits in compliance with piping codes like ASME B 31.3. Inputs like PandID, Isometric drawings, line list, material database, support standard documents etc. will be used to define the conditions of piping system and a variety of load cases like operational, sustained, occasional (wind, seismic) and expansion case etc., will be considered to qualify the system in all possible cases. Piping supports like pipe shoe, guide, spring hanger, rod hanger, cantilever bracket are used to ensure proper support locations. This paper carries a detailed analysis on critical lines connected between process equipment's to demonstrate the integrity and flexibility of the piping system. It also generates stress reports like nozzle loads and bending stresses which validates the design of high quality, timely and economic layout of refinery piping system.

000752   Chowdhury M A (NO, , ) : Relative permeability study in part of Geleki oil field of upper Assam basin. J Petrol Engng Technol 2015, 5(2), 9-14.

Relative permeability is a critical parameter for evaluation of reservoir performance. Relative permeability is a direct measure of the ability of the porous medium to allow flow of one fluid when two or more fluids are present. This flow property is the composite effect of pore-geometry, wettability, fluid saturation, saturation history, reservoir temperature, reservoir pressure, overburden pressure, rock-types, porosity and permeability types. The relative permeability curves are very important in reservoir studies. They are used in predicting production rate and recovery from the reservoirs during all recovery stages (primary, secondary, and tertiary). The wettability of a core does affect its waterflood behavior and relative permeability. Wettability affects relative permeability because it is a major factor in the control of the location, flow, and distribution of fluids in a porous medium. Present study aims at determining the relative permeability to oil and water of conventional core plugs from a parts of Geleki oil-field of upper Assam basin. This study is based on the determination of relative permeability to oil and water, and preparation of water and oil relative permeability (K_rw and K_ro) curves vs water saturation (S_W) and relative permeability ratio K_rw/K_ro curves vs oil saturation. Other aspects of the present study have been to determine irreducible water saturation and oil saturation and wettability of the reservoir rocks.

ref

000751   Chaudhary V;Gohil P P;Shaikh A A (Mechanical Engineering Dep, Faculty of Technology and Engineering, Charotar Univ of Science and Te, Changa-388 421, Email: push4679@yahoo.com ) : Development of potential composites through natural fiber reinforcement. J scient ind Res 2015, 74(2), 93-7.

Fibers are best suitable material as reinforcement, which increases properties of the emerging composite materials. The use of high strength fiber leads to new advanced composites which can be used for great strength applications. Yet, the use of medium and low strength fibers available in nature are also consuming sufficient potential for various applications where high strength is not critical but it can offer a practicable range of alternative materials to appropriate conventional material. The composite materials which are more environmentally friendly, energy efficient and recyclable have great potential market. The present work studies the various types of natural fiber available for the improvement of potential composites. The paper also discusses the methodology of the development of cotton-polyester composites using filament winding technology and hand layup method.

3 illus, 3 tables, 19 ref

000750   Chakrabarty K;Kar U (NO, Kalyani Government Engineering College, Kalyani-741 235, Email: chakrabarty40@rediffmail.com ) : State variable participation in the limit cycle of induction motor. Pramana J Phys 2015, 84(3), 423-41.

The paper presents bifurcation behaviour of a single-phase induction motor. Study of bifurcation of a system gives the complete picture of its dynamical behaviour with the change in system's parameters. The system is mathematically described by a set of differential equations in the state space. Induction motors are very widely used in domestic and commercial applications. Single-phase capacitor-run induction motors are commonly used as prime movers for fans, pumps and compressors. This paper provides a numerical approach to understand the dynamics of an induction motor in the light of bifurcation and chaos. It is seen that the dynamics of a capacitor-run single-phase induction motor cannot be ascertained by the profile of a single state variable. This paper also attempts to discuss the bifurcation behaviour of the system based on the evolution of different state variables. The bifurcation diagrams drawn looking at different state variables are different in terms of periodicity and route to chaos. The knowledge of the dynamics of the system obtained from bifurcation diagrams give useful guidelines to control the operation of the induction motor depending on the need of an application for better performance.

23 illus, 12 ref

000749   Bhuvaneshwari B;Palani G S;Karunya R;Iyer N R (NO, CSIR-Structural Engineering Research Centre, Chennai-600 113, Email: nriyer@serc.res.in) : Nano mechanical properties on the mineralogical array of calcium silicate hydrates and calcium hydroxide through molecular dynamics-CSIR-SERC. Curr Sci 2015, 108(6), 1058-65.

Molecular dynamics studies towards assessing the bulk properties of the mineralogical array of cement hydrates such as calcium silicate hydrates (C-S-H) and calcium hydroxide (CH) have been conducted. In the case of C-S-H, closely related structures of minerals such as Tobermorite (9, 11, 14) A and Jennite are taken for MD simulations, as they have similarities with C-S-H in terms of its mineralogical array. COMPASS force field with appropriate set parameters such as cut-off distances, micro-canonical ensembles was employed for the smooth running of simulations. Different supercells for the mineral systems were created and studied further. Results show the calculated mechanical properties of cement hydrates, which form an important input for developing computational model for cement hydrate systems for assessing the physico-chemical and mechanical characteristics.

5 illus, 1 table, 23 ref

000748   Barkhan M H;Zargar G H;Zakariyaei S J S (NO, , ) : Enhanced oil recovery (EOR) process through miscible gas injection: a case study of an iranian oil reservoir. J Petrol Engng Technol 2015, 5(2), 1-8.

Speedy computers and development in equations' numerical solutions have enhanced applying simulation to predict the behavior of oil and gas reservoirs. The pressure in hydrocarbon reservoirs reduces overtime due to utilization of oil and gas resources until the fluid pressure itself is no more able to transfer it to the surface, and even if it reaches to the surface, its production is not cost-effective. Whereas, large amounts of hydrocarbon resources still remain within reservoir's pores. In order to make reservoir produce as much as possible and increase its recovery factor at different stages of reduced reservoir pressure, different operations are performed on reservoirs. One of these methods is gas injection operations. Gas injection efficiency in reservoirs has been historically doubted as a useful mechanism; however, since 1950s, it is considered as an appropriate method to stabilize pressure and oil production; in addition to a proper approach to recover residual oil following water injection. Miscible and immiscible gas injections are both widely used; as the nature of Iranian reservoirs' rocks, which are almost carbonated and oil wet.

000747   Ashkan S;Siamak Y;Andrew R;Denver T (Civil Engineering Dep, North Dakota State Univ, Fargo, ND, USA, Email: frank.yazdani@ndsu.edu) : Anisotropic damage modeling of concrete subjected to freeze-thaw process. Int J civ struct Engng 2014, 5(1), 42-52.

It has been shown in the literature that the cycles of freeze-thaw (CFT) adversely affect the mechanical properties of brittle materials. To account for the effect of CFT and guided by isotropic hardening/softening theories of damage mechanics, a generalized bounding surface approach is presented. It is argued that the limit surface is a special case in such a formulation when the number of CFT is set to zero and that when subjected to freeze-thaw processes the limit surface is allowed to contract to a residual strength state based on the number of CFT. Within the formulation, specific relation for damage growth is proposed by considering the changes in ultimate strain (strain at failure). Stress-stain curves and anisotropic degradation in mechanical properties are obtained. The results are compared with available experimental data.

000746   Ananthasuresh G K (Mechanical Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: suresh@mecheng.iisc.ernet.in) : Buckminster fuller and his fabulous designs. Resonance 2015, 20(2), 98-122.

Richard Buckminster Fuller was an American designer who created fantastic designs. His non-conformist creative design ability was augmented with an urge to realize the prototypes not only for practical demonstration but also for widespread use. His creations called for new vocabulary such as synergy, tensegrity, Dymaxion, and the eponymous Fullerene. He had a design science philosophy of his own. He thought beyond the design of artifacts. He strived for sustainable living in the global world long before these concepts became important for the world to deal with. He is described as a comprehensive anticipatory design scientist. In this article, only his physical design artifacts that include two of his lasting design contributions, namely, the tensegrity structures and the geodesic domes are discussed.

13 illus, 12 ref

000745   Anand S (NO, Bioved Research Institute of Agricultural and Technology, 103/42, M.L.N., Allahabad-211 002) : Water quality survey of pipe water supply of city Allahabad. Bioved 2014, 25(1), 95-7.

Water, one of the nature's most abundant gifts, is the basic requirement for the life of all the kinds for their sustenance and development. Substandard quality and quantity of the water results in a serious threat to substance, and development. History of human civilization is another testimony to above facts, as it flourished where water availability was adequate both in quantity and quality. Hence, water is not only vital for life, but progress and prosperity of the nation is significantly dependent on water. Allahabad is an ancient city of India. On the confluence (Sangam) of the rivers Ganga, Yamuna and mythical Saraswati, Water Supply System in Allahabad city has the total availability of water 200 1pcd. Each village has the facility of piped water supply or India Mark II handpumps facilities for domestic purposes. District Allahabad has 48 rural piped water supply systems in 1680 villages. These systems have 111 handpumps, 90 overhead tanks, 6 groundwater tanks and plateau region has 4 water purifying system, 6 zonal pumping stations and nearly 4000 km. long piped water supply system. Jal Nigam looks after about rural water supply and Jal Sansthan after urban water supply. Results of study indicated that municipal tap water supply at Allahabad was found satisfactory. All parameters are under desirable limit as per Manual on water supply and treatment but Free (residual) chlorine in water sample exceed their desirable limit as per Manual on water supply and treatment (1984). It causes serious health hazard, it required proper maintenance of chlorine dose because Free (residual) chlorine reacts with organic compound of water and products disinfectants by-products (DBPs), some of which are suspected carcinogens.

1 table, 7 ref

000744   Ambily P S;Ravishankar K;Umarani C;Kumar S S (NO, CSIR-Structural Engineering Research Centre, Chennai, Email: ambilyps@serc.res.in) : Influence of micronised biomass silica on the workability and strength of alkali activated slag concrete. J scient ind Res 2015, 74(2), 98-101.

Cement production consumes huge amount of energy, in particular, arising from the calcination of raw materials. The development of new binders by alkaline activation is one of the present research topic. The new binder materials that can replace Portland cement (PC), by alkali activation, consumes less energy and generates less carbon dioxide than PC. This paper presents an experimental study aimed to produce concrete without Portland cement using ground granulated blast furnace slag (GGBS) and micronized biomass silica (MBS) as binding material activated by sodium hydroxide and sodium silicate as alkaline activator. Mortar and concrete mixes were prepared by various percentage replacements of GGBS by MBS. The percentage of MBS tried for concrete was 0%, 10%, 20%, and 30% by volume. The properties of concrete, such as slump, fresh density and compressive strength at various ages were determined. From the study it was found that, 10% replacement of MBS gives higher compressive strength value and up to 20% replacement of MBS is possible without reduction in strength and workability when compared to control mix (0% MBS).

1 illus, 3 tables, 10 ref

024065   Zenkour A M (Mathematics Dep, Faculty of Science, King Abdulaziz Univ, P.O. Box 80203, Jeddah 21589, Saudi Arabia, Email: zenkour@gmail.com) : Simplified four-unknown shear and normal deformations theory for bidirectional laminated plates. Sadhana 2015, 40(1), 215-34.

This paper presents a simplified 4-unknown shear and normal deformations theory for the bending analysis of cross-ply laminated plates. The present theory accounts for an adequate distribution of transverse shear strains through the plate thickness and tangential stress-free on the plate surfaces. The effect of normal strain is also included. The governing, equilibrium equations and boundary conditions are derived by employing the virtual work principle. Numerical results for stresses and displacements are compared well with those obtained using 3-D elasticity solution.

15 illus, 30 ref

024064   Verma M;Patidar D;Baboo M;Sharma K B;Saxena N S (NO, , ) : Storage modulus and glass transition temperature of MWNT/PMMA polymer nanocomposite films with different WT% of MWNT. J Nanosci Nanoengng Applic 2014, 4(2), 28-33.

This paper presents the study of behavior of storage modulus and glass transition temperature of MWNT/PMMA polymer nanocomposites prepared by solution casting method, with different (0, 0.1, 0.2, 0.3, 0.5, 1, 5, 10) wt% of MWNT in the PMMA matrix. Dynamic mechanical analysis has been done in tension mode. Storage modulus increases with CNT loading in matrix except for 0.1, 0.2 wt% CNT samples, for 0.5 wt% sample onwards to 10 wt% increases continuously, whereas glass transition temperature is found to increase smoothly for all samples, which is explained in terms of the interactions between polymer-MWNT and MWNT-MWNT.

024063   Vamsi V N;Annepu B R (NO, , ) : Series resistor method for higher signal-to-noise ratio and high sensitivity in superconducting nanowire single-photon detectors. J Nanosci Nanoengng Applic 2014, 4(2), 1-4.

A series resistor method has been presented for higher signal-to-noise and high sensitivity in superconducting nanowire single-photon detectors (SNSPD). This method has given a very high useful data yields exceeding 50% while still maintaining pure single-photon operation and wide dynamic range. The SNSPD signal is roughly proportional to the nanowire width, so narrow nanowire have poor signal-to-noise ratio (SNR) at widths from 4-30 nm and fabrication at these length scales is extremely challenging. In this paper, the authors have addressed the SNR issues and demonstrated that the higher SNR and high sensitivity can be achieved at 30-nm-nanowire superconducting single-photon detector for different IB values.

024062   Tiwari V;Thakur R S (NO, Maulana Azad National Institute of Technology (MA-NIT), Bhopal-462 007, Email: vivek.vktonline@gmail.com) : Contextual snowflake modelling for pattern warehouse logical design. Sadhana 2015, 40(1), 15-33.

Pattern warehouse provides the infrastructure for knowledge representation and mining by allowing the patterns to be stored permanently. The goal of this paper is to discuss the pattern warehouse design and related quality issues. In the present work, we focus on conceptual and logical design of pattern warehouse, by introducing a context and 'kind of knowledge' hierarchy to this end. For the simplicity, association kinds of patterns are considered for running examples. We have extended well-known 'snowflake' schema for pattern warehouse logical design. We have introduced a new concept hierarchy "kind of knowledge' which helps to arrange patterns, the four quality forms (QF) are also discussed which will work as guidelines for pattern warehouse conceptual and logical design to minimize the evaluation and maintenance cost. In particular, we address the three main issues: (i) conceptual design, (ii) snowflake schema and (iii) pattern refreshment.

4 illus, 2 tables, 28 ref

024061   Tian W;Dang F;Xie Y (School of Civil Engineering, Chang'an Univ, Xi'an 710061, China, Email: tianwei@chd.edu.cn) : Quantitative study on crack of meso-damage and fracture concrete based on CT technique. Sadhana 2015, 40(1), 263-76.

Meso-mechanics experiment of concrete specimen is carried out by means of CT technology, the whole degradation deformation process of meso-cracks generation, propagation, coalescence and failure is obtained under uniaxial compression condition. Based on CT image of concrete meso-damage evolution, the recognition and extraction of meso-cracks are realized by means of the digital image-processing (DIP) technique, and the basic geometrical characteristics of meso-crack patterns are statistically analysed from length, width and area. The quantitative analysis of the meso-fracture process of concrete materials is performed. The results demonstrate that the quantitative analysis of the internal meso-crack of concrete can be taken as a quantitative index to reflect the damage and fracture process thereby the meso-fracture mechanism of concrete material is thoroughly investigated. So it has brought forth some new ideas to the study of damage evolution law of concrete under uniaxial compression condition.

14 illus, 2 tables, 12 ref