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Poongodi G.,Quaid e Millath Government College for Women | Poongodi G.,Presidency College at Chennai | Mohan Kumar R.,Presidency College at Chennai | Jayavel R.,Anna University
Ceramics International | Year: 2014

Pure and S doped ZnO thin films have been synthesized by hydrothermal method at 90 °C for 3 h. Powder XRD analysis shows the formation of hexagonal wurtzite phase of ZnO. The incorporation of S in ZnO lattice was confirmed by XPS analysis. FE-SEM results reveal that the synthesised thin films possess vertically aligned 1D rod structure with hexagonal morphology. UV-visible transmission spectral studies showed that the optical band gap of ZnO was reduced by S doping. PL spectrum confirmed that the effective S doping enhances the visible emission and suppresses the near band gap emission. The effect of S doping on the photocatalytic activity of ZnO thin films for the degradation of methylene blue dye was studied under visible light illumination and the results showed that the S doping provokes appreciable degradation of MB. Furthermore, the S doped ZnO film showed enhanced antibacterial activity compared to pure ZnO film against a Gram negative (Escherichia coli) and a Gram positive (Staphylococcus aureus) bacteria. This ensures that the S doped ZnO thin films can act as a UV blocking agent with enhanced photocatalytic and antibacterial activities. © 2014 Elsevier Ltd and Techna Group S.r.l.

Poongodi G.,Quaid e Millath Government College for Women | Poongodi G.,Presidency College at Chennai | Kumar R.M.,Presidency College at Chennai | Jayavel R.,Anna University
Ceramics International | Year: 2015

Nanostructured Nd doped ZnO thin films were deposited on glass substrate by a sol-gel spin coating technique. The prepared thin films were subjected to structural, morphological, optical, photocatalytic and antibacterial studies. XRD studies confirm that all the prepared films possess hexagonal wurtzite structure. FESEM images revealed the granular morphology of the films without any crack and the crystallite size decreased with Nd doping. UV-visible transmission spectra show that the substitution of Nd in ZnO leads to band gap reduction. The influence of Nd doping on the photocatalytic activity of ZnO for the degradation of methylene blue dye was studied under visible light illumination. The decrease in grain size and light absorption over an extended visible region by Nd ion doping in ZnO film contributed equally to improve the photocatalytic activity. The optical density measurement of the films against Escherichia coli and Staphylococcus aureus bacteria showed better bactericidal activity at a higher level of Nd doping in ZnO. © 2014 Elsevier Ltd and Techna Group S.r.l.

Sheshasaayee A.,Quaid e Millath Government College for Women | Jasmine C.,University of Madras
International Journal of Control Theory and Applications | Year: 2016

Skeletal maturity is visually examined through the comparison of hand radiographs with an image atlas that acts as a standard reference. Most general ones are the techniques by Greulich and Pyle (GP) and Tanner & Whitehouse (TW). These methods try to do the extraction, measurement, classification of bones and the distances between the bones are affected due to the high dimensionality of the biological material and also the differences arising in the development of bone that results from age, gender in addition with ethnic origin. Content Based Image Retrieval (CBIR) yields a reliable solution without any delineation and measurement of bones. With a left hand-wrist radiograph provided as the input, the system does the estimation of the bone age by employing techniques for pre-processing, feature extraction, feature selection, Relevance Score (RS) and similarity matching. Initially a noise in the image samples is removed by using Hybrid Principal Component Analysis (HPCA). In feature extraction phase six important features such as Color histogram and color moments, Gabor Wavelets Transform (GWT), Edge direction histogram, GIST features, Adaptive Local Binary Pattern (ALBP) and epiphyseal Region Of Interest (eROI) features is extracted. Harmony Search (HS) is used as a feature selection technique for reducing the feature vector size. The features that are selected are provided as input into a Hybrid Fuzzy Neural Network (HFNN) classifier to assist in acquiring the search purpose from the user and further enhance the retrieval results. The relevance score computed features are fed into a Discriminative Dictionary Learning (DDL) classifier that yields the output as the class to whom the radiograph is grouped, again which is mapped to the bone age that is final. This system proposed assures precise and reliable Bone Age Assessment (BAA) for the ages ranging from 0-18 years for both the cases of girls and boys. Support BAA through the comparison of the epiphyses of a present case to the same kind of cases with bone age validated by CBIR. The performance of DDLsystem was assessed with the aid of parameters like precision, recall, sensitivity, specificity and accuracy. © International Science Press.

Padmaja S.,Bharathiar University | Sheshasaayee A.,Quaid e Millath Government College for Women
International Journal of Engineering and Technology | Year: 2016

The proposed work does an improved K-means clustering algorithm for identifying internet user behaviour. Web data analysis includes the transformation and interpretation of web log data find out the information, patterns and knowledge discovery. The efficiency of the algorithm is analyzed by considering certain parameters. The parameters are date, time, S_id, CS_method, C_IP, User_agent and time taken. The research done by using more than 2 years of real data set collected from two different group of institutions web server.this dataset provides a better analysis of Log data to identify internet user behaviour.

Sheshasaayee A.,Quaid e Millath Government College for Women | Angela Deepa V.R.,Quaid e Millath Government College for Women
Advances in Intelligent Systems and Computing | Year: 2016

Construction of powerful computer systems to understand the human languages or natural languages to capture information about various domains demands morphologically featured modeled architected appropriately in a core way. Morphological analysis is a crucial step that plays a predominant role in the field of natural language processing. It includes the study of structure, formation, functional units of the words, identification of morphemes to endeavor the formulation of the rules of the language. Since natural language processing applications like machine translation systems, speech recognition, information retrieval rely on large text data to analyze using linguistic expertise is not viable. To overcome this issue morphological analysis using unsupervised settings is incorporated. It is an alternative procedure that works independently to uncover the morphological structure of the languages. This paper gives a theoretical model to analysis morphologically the structure of the Tamil language in an unsupervised way. © Springer India 2016.

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