Showing papers by "PSG College of Technology published in 2008"

Investigation on dielectric relaxations of PVP–NH4SCN polymer electrolyte

Abstract: Poly (N-vinyl pyrrolidone) (PVP) and ammonium thiocyanate (NH4SCN) based polymer films with different compositions have been prepared by solution casting technique. The amorphous nature of the polymer electrolytes has been confirmed by XRD analysis. The FTIR analysis confirms the complex formation of the polymer with the salt. The conductivity analysis shows that the 20 mol% ammonium thiocyanate doped polymer electrolyte has high ionic conductivity and it has been found to be 1.7 × 10−4 S cm−1, at room temperature. From the admittance plot, the activation energy has been found to be low for 20 mol% salt doped polymer electrolyte. The dielectric behavior has been analyzed using dielectric permittivity (e∗), dissipation factor (tan δ) and electric modulus (M∗) of the samples.

Effect of drilling induced damage on notched tensile and pin bearing strengths of woven GFR-epoxy composites

Abstract: Analytical and experimental studies were made to evaluate the notched tensile and pin bearing strengths of the woven glass fiber reinforced (GFR)-epoxy composite laminates. The symmetric glass/epoxy woven mat cross-ply laminates containing 16 woven mats were prepared using hand lay-up technique with 45% of volume fraction. The laminates were cut into specimens as per ASTM standards. The experiments were done at three different feed rates, spindle speeds and hole diameters to examine the influence of drilling parameters on the notched tensile strength and bearing strengths of the laminates. The design of experiments and analysis of variance (ANOVA) techniques of Taguchi, were utilized to study the statistical influence of the drilling parameters on the extension of delamination. The fracture data of center-hole tensile specimens were correlated using a modification in one of the stress fracture criteria viz., the point stress criterion (PSC). The bearing strength was correlated with notched and un-notched tensile strengths of the woven fabric composite laminates.

Drilling of hybrid aluminium matrix composites

Abstract: This paper presents the influence of cutting parameters on thrust force, surface finish, and burr formation in drilling Al2219/15SiCp and Al2219/15SiCp-3Gr composites. The composites were fabricated using the liquid metallurgy method. The tools used were commercially available carbide and coated carbide drills. The results revealed that feed rate had a major influence on thrust force, surface roughness, and exit burr formation. Graphitic composites exhibit lesser thrust force, burr height, and higher surface roughness when compared to the other material. The reduced thrust force and burr height is attributed to the solid lubricating property of the graphite particles. The higher surface roughness value for Al2219/15SiCp-3Gr composite is due to the pullout of graphite from the surface. The chips formed when machining graphitic composites are more discontinuous when compared to SiCp reinforced composites and hence advantageous.

Evaluation of Lignocellulosic Wastes for Production of Edible Mushrooms

Abstract: The degradation of lignocellulosic wastes such as paddy straw, sorghum stalk, and banana pseudostem was investigated during solid-state fermentation by edible mushrooms Pleurotus eous and Lentinus connotus. Biological efficiency of 55-65% was observed in paddy straw followed by sorghum stalk (45%) and banana pseudostem (33%) for both fungal species. The activity of extracellular enzymes, namely cellulase, polyphenol oxidase, and laccase, together with the content of cellulose, lignin, and phenols, was studied in spent substrates on seventh, 17th, and 27th days of spawning, and these values were used as indicators of the extent of lignocellulosic degradation by mushroom. Both the mushroom species proved to be efficient degraders of lignocellulosic biomass of paddy straw and sorghum stalk, and the extent of cellulose degradation was 63-72% of dry weight (d.w.), and lignin degradation was 23-30% of the d.w. In banana pseudostem, the extent of the degradation was observed to be only 15-22% of the d.w. for both lignin and cellulose. Preferential removal of cellulose during initial growth period and delayed degradation of lignin were observed in all three substrates. This is associated with decrease in activity of cellulase and polyphenol oxidase and increase in laccase activity with spawn aging in spent substrates. Thus, bioconversion of lignocellulosic biomass by P. eous and L. connotus offers a promising way to convert low-quality biomass into an improved human food.

Network intrusion detection using feature selection and Decision tree classifier

Abstract: Security of computers and the networks that connect them is increasingly becoming of great significance. Machine learning techniques such as Decision trees have been applied to the field of intrusion detection. Machine learning techniques can learn normal and anomalous patterns from training data and generate classifiers that are used to detect attacks on computer system. In general the input to classifiers is in a high dimension feature space, but not all features are relevant to the classes to be classified. Feature selection is a very important step in classification since the inclusion of irrelevant and redundant features often degrade the performance of classification algorithms both in speed and accuracy. In this paper, we have considered three different approaches for feature selection, Chi square, Information Gain and ReliefF which is based on filter approach. A comparative study of the three approaches is done using decision tree as classifier. The KDDcup 99 data set is used to train and test the decision tree classifiers.

Mechanical and three‐body abrasive wear behaviour of SiC filled glass‐epoxy composites

Abstract: Fiber/filler reinforced polymer composites are known to possess high strength and attractive wear resistance in dry sliding conditions. How these composites perform in abrasive wear situations needs a proper understanding. Hence, in this research article the mechanical and three-body abrasive wear behaviour of E-glass fabric reinforced epoxy (G-E) and silicon carbide filled E-glass fabric reinforced epoxy (SiC-G-E) composites are investigated. The mechanical properties were evaluated using Universal testing machine. Three-body abrasive wear tests are conducted using rubber wheel abrasion tester wherein two different loads and four varying abrading distances are employed. The results showed that the wear volume loss is increased with increase in abrading distance and the specific wear rate decreased with increase in abrading distance/load. However, the presence of SiC particulate fillers in the G-E composites showed a promising trend. The worn surface features, when examined through scanning electron microscopy, show higher levels of broken glass fiber in G-E system compared to SiC- filled G-E composites. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers

DESSAC: a decision support system for quantifying and analysing agility

Abstract: This paper traces the origin and development of agile manufacturing. The industrial sectors which have embraced agility are today's winners in the competitive markets. This situation warrants the need of assessing the activities to be undertaken to acquire agility. For this purpose, this paper advocates the adoption of a 20 criteria agile model. In order to implement this model effectively, the agility level at which a company currently operates needs to be quantified. For this purpose, a quantification model incorporated with the 20 criteria agile model was adopted from literature and proposed after refinement. Applying this refined quantifying model in real time practice is a time consuming and tedious process. In order to overcome this difficulty, a decision support system named DESSAC (DEcision Support System for quantifying Agile Criteria) was developed. DESSAC was demonstrated to a group of competent personnel of an electronics switch manufacturing company situated in India. These personnel could op...

Influence of cenosphere filler additions on the three‐body abrasive wear behavior of glass fiber‐reinforced epoxy composites

Abstract: The dry three-body abrasive wear behavior of bi-directional glass fabric reinforced epoxy composites with and without cenosphere filler have been studied using dry sand/rubber wheel abrasion tester. The angular silica sand particle sizes in the range 200–250 μm were used as dry and loose abrasives. The wear experiments have been conducted at two different loads viz., 22 and 32 N and different abrading distances viz. 270, 540, 810, and 1,080 m. The wear volume increases with an increase in load/abrading distance for all composites. From the experimental wear data it was observed that the abrasive wear of the composites dependent on the applied load and abrading distance. Further, the cenospheres filler inclusion in glass fiber reinforced epoxy (G-E) composite showed poor abrasive wear performance. Scanning electron microscopy was used to study the morphology of the worn surface features of composites and to understand the mechanisms involved in the wear analysis. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers

Nanotechnology and Protective Clothing for Defence Personnel

Abstract: Defence personnel face multiple threats from different quarters, like terrorist groups and rogue nations, who own not only advanced lethal weapons but also chemical and biological warfare weapons. The present day protective clothing system used by the defence sector is vulnerable to modern weapons and also have some inherent weaknesses like high cost, bulkiness and discomfort in wearing. Nanotechnology- based materials offer a promising future in this areadue to their extraordinary physical, chemical, mechanical, and electrical properties at nano-level.This paper outlines the various developments related to the application of nanotechnology inproducing lightweight and comfortable protective clothing for the military personnel and also some new developments like sensor, energy storage, conductivity, and decontaminant fabrics.Defence Science Journal, 2008, 58(4), pp.451-459, DOI:http://dx.doi.org/10.14429/dsj.58.1667

Growth, spectral and thermal properties of KAP single crystals in the presence of DL-Alanine and L-Methionine amino acid dopants

Abstract: Single crystals of potassium acid phthalate (KAP) and amino acid (DL-Alanine, L-Methionine) doped KAP were grown from aqueous solutions by slow cooling method. The grown crystals were characterized using powder X Ray diffraction (XRD) and Fourier Transform Infrared (FTIR) analysis. The thermal stability of KAP in the presence of dopants was analysed using Thermogravimetric and Differential Scanning caloriemetric (TGA/ DSC) studies and the maximum temperature for non linear optical application of this compound in the presence of dopants was found out. The transmittance of KAP was found to increase in the presence of dopants. Etch pits were observed for all the crystals using different etchants. Vickers microhardness tests were performed to study the mechanical stability of the crystals. The hardness of DL-alanine doped KAP is more than that of L-alanine doped KAP crystal. The dielectric constant and loss were determined as a function of temperature. Frequency response of the dielectric constant and dielectric loss factor have been studied over the frequency range of 50Hz – 5MHz. Second harmonic generation (SHG) was confirmed in all the crystals using the Kurtz and Perry powder technique. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Removal of artifacts from EEG signals using adaptive filter through wavelet transform

Abstract: This paper presents an adaptive method for removing electroocular (EOG) artifacts in the electroencephalogram (EEG) records. Artifacts in EEG signals are caused by various factors, like line interference, EOG ( electro-oculogram ) and ECG ( electrocardiogram). These noise sources increase the difficulty in analyzing the EEG and obtaining clinical information. For this reason, it is necessary to design specific filters to decrease such artifacts in EEG records. In this paper, we proposed an adaptive filtering method for removing ocular artifacts from EEG recordings using wavelet transform.

A proposal: evaluation of OEE and impact of six big losses on equipment earning capacity

Abstract: In the recent past maintenance strategy has gained heightened importance in organisations and requires the manufacturing and maintenance managers to develop and follow well devised production and maintenance plans. Remarkable improvement has taken place in the maintenance management of physical assets and productive systems, to reduce wastage of energy and resources. Overall Equipment Effectiveness (OEE) methodology is a proven approach to increase overall performance of equipment. In the present paper, a method is proposed to evaluate OEE by including a factor known as usability, in the OEE calculation method. Further, an approach is developed to evaluate the earning capacity of addressing the six big losses, with incremental improvement in OEE, as an extension to the maturity of OEE.

On the single server batch arrival retrial queue with general vacation time under bernoulli schedule and two phases of heterogeneous service

Abstract: We consider a single server retrial queue with batch arrivals, two phases of heterogeneous service and a general vacation time under Bernoulli schedule. We carry out steady state system size distribution of number of customers in retrial group, expected number of customers in retrial group and expected waiting time of the customers in the orbit. We discuss its application of the proposed model to the analysis of a communication protocol.

Mechanical and three-body abrasive wear behaviour of three-dimensional glass fabric reinforced vinyl ester composite

Abstract: The mechanical and three-body abrasive wear behaviour of two- and three-dimensional E-glass woven fabric reinforced vinyl ester composites were studied in this article. The mechanical properties were evaluated using universal testing machine as per ASTM D-638. Three-body abrasive wear tests were conducted using rubber wheel abrasion tester (RWAT) under different abrading distances at two loads, wherein the wear volume loss were found to increase and that of specific wear rate decrease. The results indicate that the three-dimensional glass woven fabrics in vinyl ester (G 3D –V) have significant influence on wear under varied abrading distance/loads. Further, it was found that G 3D –V composite exhibited lower wear rate compared to two-dimensional glass woven fabric reinforced vinyl ester (G 2D –V) composite. The worn surface features, as examined through scanning electron microscope (SEM), show ruptured glass fiber in G 2D –V composite compared to G 3D –V composites.

Comparitive studies on ring rotor and vortex yarn knitted fabrics

Abstract: Ring, Rotor and Air vortex spinning systems provide yarn with different structures and properties. Each system has its limitations and advantages in terms of technical feasibility and economic viability. 30's Ne, 100%cotton yarns were produced from the above systems and knitted in single jersey machine .The Rotor Spun yarns found with frequent breakage during knitting. Comparatively good knitting performances have shown by the Ring and Air vortex yarns. Tensile, evenness and hairiness of the yarns and bursting strength, abrasion resistance, pilling, drapability and color matching of the knitted fabrics were studied. The Ring spun yarns have high strength, low imperfection, and good bursting strength. It has high 'S3' value. Abrasion resistance of Rotor and Vortex yarns made fabrics were found higher than the ring spun yarns. Ring yarn knitted fabric has high bursting strength, Air-vortex yarn knitted fabric has poor drape due to stiffer yarn structure and the MVS yarn fabric has poor pilling resistance. Rotor, MVS yarns made fabrics have good abrasion resistance. Drapability of Vortex yarn knitted fabrics was poor than ring and Rotor yarn knitted fabrics. Good and equal depth of dye shade was found with Ring and Air vortex yarn made knitted fabrics. Ring yarn knitted fabric has shown smooth feeling than the other two fabrics.

The origin, history and definition of Six Sigma: a literature review

Abstract: Six Sigma has set a new paradigm of excellence in the business environment and is enjoying great popularity. Even though Six Sigma has been in practice in the last two decades, no effort has been made to develop a holistic definition that includes all of the dimensions of Six Sigma. In this paper, the various definitions that exist in the literature have been critically evaluated and a new holistic definition has been proposed. Also, there is a lot of ambiguity in the literature with respect to the origin of Six Sigma. An effort is made to eliminate such confusion by tracking the origin and growth of Six Sigma. Furthermore, in order to facilitate effective implementation, the principles of Six Sigma were identified from the literature. Finally, the misconceptions of Six Sigma are cleared by demystifying its myths.

Energy-Efficient, High Performance Circuits for Arithmetic Units

Abstract: Adders and multipliers are the most important arithmetic units in a general microprocessor and the major source of power dissipation. Various architecture styles exist to implement these units, each having their own merits and demerits. However, due to continuing integrating intensity and growing needs of portable devices, low power design is of prime importance. In addition, much power is dissipated due to a large number of spurious transitions on internal nodes in power hungry multiplier structures. We present a new full adder structure based on complementary pass transistor logic (CPL) which is faster and more energy efficient than the existing structures. We also propose a new technique of implementing multiplier circuit using decomposition logic which improves speed and reduces power consumption by reducing the spurious transitions on internal nodes. Combined with the new adder structure and the decomposition logic, there is substantial improvement in the performance of the multiplier structures. With the help of these state of the art designs, it would be possible to design highly power efficient processors, especially digital signal processors. We have used TSPICE for simulation in the TSMC 180 nm technology.

Prevalence of job strain among Indian foundry shop floor workers.

Abstract: Global competition in manufacturing sector demand higher productivity levels. In this context, workers in this sector are set with high output targets, leading to job strain. In addition to the strain, hazardous conditions also prevail in some of the manufacturing processes like foundry activities. This paper attempts to appraise the prevalence of job strain among foundry shop floor workers in India with the help of Demands-Control model (8). In this study, data was collected through a survey using 49-item Job Content Questionnaire (JCQ) (9), a widely used and well-validated test for job strain. Then the data was subjected to statistical analysis after ascertaining the reliability. This survey has revealed that 25% of workers in foundry were experiencing high job strain. Hazardous working conditions, limited decision making authority, etc. appear to be the main contributing factors for the higher levels of strain.

Dyes from the leaves of deciduous plants with a high tannin content for wool

Abstract: The aqueous leaf extracts of five different deciduous plants, namely, silver oak, flame of the forest, tanner’s senna, wattle and serviceberry, were used on their own and in combination with aluminium sulphate, stannous chloride and ferrous sulphate to dye wool by a simultaneous mordanting technique The washing and light fastness properties of the developed shades were moderate to good Based on the CIE 2000 spectral colour coordinate values (K/S, ΔL, Δa, Δb and ΔE), the developed shades were classified into four groups: yellow/brown, yellow, orange and dark grey The use of aluminium sulphate gave medium shades (K/S = 824), while the stannous chloride and ferrous sulphate mordants provided deep shades (K/S = 305) Statistical analyses have shown that only the type of mordant and not the dye source significantly influenced the development of colour on wool Hence, it was theoretically possible to use five selected leaves as a single mixture to produce four different colours on wool