Abstract

Spatial data were collected from map 1973, IRS 1A, IRS 1B of 1989 and 2001. A spatial model was created based on these data. This GIS application, based on available and easily developed digital data, provides realistic and valuable information in a short time frame. This paper includes three major stages: (1) data preparation and pre-processing, (2) boundary detection and (3) modeling and results presentation. These results offered some insights for erosion control on the 11o 40’ Northing to 11o 30’ Northing of Tamilnadu state of Indian east coast area. This paper helps to identify the coastal erosion and accretion.

Abstract

Axisymmetric vibration of an infinite Pyrocomposite circular cylinder made of inner solid and outer hollow pyroelectric layer belonging to crystal class 6 bonded together by a Linear Elastic Material with Voids (LEMV) is studied. The exact frequency equation is obtained for the traction free outer surface with continuity conditions at the interfaces.  Numerical results in the form of data and dispersion curves for the first and second mode of the axisymmetric vibration of the cylinder ceramic - 1/ Adhesive / ceramic - 2 by taking the adherents as BaTio3 and the adhesive layer as an existing Carbon Fibre Reinforced Polymer (CFRP) or as a hypothetical LEMV layer with and without voids are compared with a pyroelectric solid cylinder. The damping is analyzed through the imaginary part of the complex frequency.

Abstract

The advantages of using ceramics in advanced heat engines can include increased fuel efficiency due to higher engine operating temperatures and more compact designs with lower capacity cooling system. Future internal combustion engines may be characterized by near zero emission levels along with low specific fuel consumption. Homogenous combustion that is formed inside the engine cylinder has the potential of providing near zero emission level with better fuel economy. However, the accomplishment of homogeneous combustion depends on the air flow structure inside the combustion chamber, fuel injection conditions and air turbulence as well as ignition conditions. Various methods and procedures are now being adopted to create homogeneous combustion inside the engine cylinder. In modern design, we see porous ceramic materials being introduced inside the combustion chamber to achieve homogeneous combustion. This paper investigates and reviews the desirable structures, types and properties of such porous ceramic materials and their positive influence on the combustion process.

Abstract

The service life prediction of hydroxyl terminated polybutadiene filled with crystalline material ammonium perchlorate (HTPB/AP), composite solid propellant, was carried out by observing the behaviour of the propellant under accelerated conditions at different elevated temperatures. The specimens were oven aged at 60 ºC and 55 ºC to study the effect of time on the ageing behaviour. The mechanical properties like initial modulus, percentage elongation at break were observed for HTPB/AP propellant from tension test, using computer controlled universal testing machine (UTM). The storage life of HTPB based composite solid propellant was obtained as 11.4 years using the Arrhenius equation. The activation energy value calculated was comparable to those obtained in other related works.

Abstract

This paper deals with the development of accurate shrinkage and warpage prediction model for plastic injection molded part using artificial neural networks. For training, testing of the shrinkage and warpage model, a number of MoldFlow (FE) analyses have been carried out using Box-Behnken Response Surface (BBRS) design technique by considering the process parameters such as mold temperature, melt temperature, packing pressure, packing time, cooling time and injection pressure. The shrinkage and warpage values were found by analyses which were done by MoldFlow plastic insight (MPI) 5.0 software. The artificial neural network model was developed using multilayer perceptron back propagation algorithm using train data and tested using test data. To judge the ability and efficiency of the model to predict the shrinkage and warpage values, percentage deviation and average percentage deviation has been used. The finite element results show that the adaption of back propagation algorithm in artificial neural networks achieved a very satisfactory prediction accuracy of 91.920498%, 90.857614% for warpage and shrinkage respectively.

Abstract

The determination of cutting forces through experimental methods is prevalent as there exist no general mathematical models for the prediction of cutting forces with respect to machining and material parameters. However, undertaking such experiments for measuring such forces consistently is expensive and time-consuming. In particular, when machining composite materials, obtaining specimens with the required specifications can be extremely difficult. In the work reported here, a multi-layered perception feed forward artificial neural network has been developed to evaluate and compare the cutting forces developed during the machining of glass/epoxy, graphite/epoxy and kevlar/epoxy composites (Ramkumar et al, 2004). The fibre orientation, composition and the depth of cut undertaken were chosen as input parameters for this purpose. The cutting force values evaluated using finite element methods were used for training the artificial neural network. The artificial neural network outputs are compared with the desired output values and provided maximum error reduction. Finally, the comparison of the neural network output results with the results obtained from experiments has shown an acceptable level of convergence.

Abstract

Surface finish and surface hardness of the components play vital role in quality of products. In most of the conventional finish machining process only surface finish will be improved, but improvement on surface hardness is less considerable. More over all finishing process are metal cutting in nature and introduces tensile stresses in the surface layer. But instead of tensile stress, if compressive stresses are introduced in surface layer, it will improve various properties of components like fatigue strength. Therefore the requirement in finishing an industrial component is that the process should improve surface finish, surface hardness and induce compressive stresses in the surface layer. A process of finishing by surface plastic deformation can meet this requirement.

One of such process, which was in use since long time is “Burnishing”. Even though the process is an old one its process parameters were not fully established, because of which it is not finding wide range of industrial application. In Burnishing, the surface layer will be plastically deformed with the help of a Ball or Roller which is harder than the work material. The process parameters include Burnishing Force, Burnishing Speed, Burnishing Feed, and Number of Tool Passes.

In the present study external burnishing tool is used to perform roller burnishing process on EN 8 alloy steel to study the surface properties variation by varying the burnishing parameters like force, speed, feed and number passes.

Abstract

Self Compacting Concrete (SCC) is a complex system that is usually proportioned with one or more mineral admixtures and more than one chemical admixture. Correct selection of aggregates, its size, gradation and content, along with adjustments in the rhelogy of the paste is essential for the SCC. To have successful design of SCC mix it is essential to have a higher level of quality control, a grater awareness of aggregate gradation, control over the mix water and use of highly advanced high range water reducing admixtures and the viscosity enhancers and have a clear understanding of the role of the various constituents in the mix and their effects on the fresh and hardened properties. Damage in Concrete structures due to fire depends to a great extent on the intensity and duration of fire. The distress in the Concrete manifests in the form of cracking and spalling of the Concrete surface. The Thermal incompatibility between components of concrete causes cracking in Concrete at elevated temperatures that reduces its durability.

This paper presents an experimental investigation on the Residual Compressive Strength of Glass fibre reinforced Self Compacting Concrete using Alkali-Resistant Glass Fibres subjected to temperatures 2000c, 4000c and 6000c for various grades of Concrete  M35, M40, M 50 and M 55.

Abstract

Concrete Filled Steel Tubular (CFST) composite columns have been used as bridge piers and columns in multistory buildings etc. It is now widely accepted that concrete filled steel tubular composite columns are well suited as compression members in high-rise buildings, long span, heavy loading and seismic structures. However there are limitations to its applications mainly due to lack of design guidance.

This paper deals with the confinement effects of concrete filled steel tubular composite column subjected to different axial loading conditions and the effect of slenderness. The columns were circular in cross-section with constant D/t and slenderness ratio varies from 3 to 12. The experimental study includes for the confinement effect that the axial load applying on the steel only, on the concrete core only and both the concrete and steel. The bond between the steel and internal core concrete was critical in determining the formation of local buckling. In slenderness effect when the slenderness ratio is very low the column fails due to yielding of the steel and crushing. When the slenderness ratio is large, the column fails by elastic buckling.

Abstract

The problem of recovering an image from noisy data arises in many different areas of scientific investigation and medical imaging. The traditional methods behave poorly when the object to recover has edges.

A new system of representation, namely, the curvelets, was developed over several years in an attempt to break an inherent limit plaguing wavelet denoising of images. The author(1) and standard images were denoised using both wavelet and curvelet transforms and results are presented in this paper. It has been found that the  curvelet reconstructions exhibit higher perceptual quality than wavelet-based reconstructions, offering visually sharper images and, in particular, higher quality recovery of edges and of faint linear and curvilinear features. Existing theory for curvelet transform suggests that this new approach can outperform wavelet methods in certain image reconstruction problems, such as image denoising and compression.