Design and Development of Density-Based Effective Document Clustering Method Using Ontology

Text document clustering is used to separate a collection of documents into several clusters by allowing the documents in a cluster to be substantially similar. The documents in one cluster are distinct from documents in other clusters. The high-dimensional sparse document term matrix reduces the clustering process efficiency. This study proposes a new way of clustering documents using domain ontology and WordNet ontology. The main objective of this work is to increase cluster output quality. This work aims to investigate and examine the method of selecting feature dimensions to minimize the features of the document name matrix. The sports documents are clustered using conventional K-Means with the dimension reduction features selection process and density-based clustering. A novel approach named ontology-based document clustering is proposed for grouping the text documents. Three critical steps were used in order to develop this technique. The initial step for an ontology-based clustering approach starts with data pre-processing, and the characteristics of the DR method are reduced with the Info-Gain collection. The documents are clustered using two clustering methods: K-Means and Density-Based clustering with DR Feature Selection Process. These methods validate the findings of ontology-based clustering, and this study compared them using the measurement metrics. The second step of this study examines the sports field ontology development and describes the principles and relationship of the terms using sports-related documents. The semantic web rational process is used to test the ontology for validation purposes. An algorithm for the synonym retrieval of the sports domain ontology terms has been proposed and implemented. The retrieved terms from the documents and sport ontology concepts are mapped to the retrieved synonym set words from the WorldNet ontology. The suggested technique is based on synonyms of mapped concepts. The proposed ontology approach employs the reduced feature set in order to clustering the text documents. The results are compared with two traditional approaches on two datasets. The proposed ontology-based clustering approach is found to be effective in clustering the documents with high precision, recall, and accuracy. In addition, this study also compared the different RDF serialization formats for sports ontology.

     

Grappling with modern technology: interruptions mediated by mobile devices impact older workers disproportionately

Information Systems and e-Business Management - Mobile technologies have dramatically increased the number of work-related interruptions. In many organizations, employees must remain accessible and...     

Dielectric spectroscopic studies on polypyrrole glucose oxidase films

An investigation was made into the dielectric spectroscopic characteristics of p-toluene sulfonate (PTS) doped polypyrrole (PPY) films in the presence and absence of immobilized glucose oxidase (GOX) in three different configurations: Al-PTS-PPY-Al-PTS-PPY/GOX-Al, and Al-PTS-PPY/GOX/β-D -glucose-Al, respectively. Measurement of dielectric loss and capacitance yielded valuable information about the dielectric properties of GOX immobilized in PTS doped PPY films. The effect of both the temperature and varying βD -glucose concentrations on the mobility of the charge carriers in these films was also systematically studied. © 1996 John Wiley & Sons, Inc.     

Synthesis of cyclic carbonate from allyl glycidyl ether and CO2 over silica-supported ionic liquid catalysts prepared by sol-gel method

A silica-supported ionic liquid (Im-IL) was proven to be an effective heterogeneous catalyst for solventless synthesis of cyclic carbonate from allyl glycidyl ether (AGE) and carbon dioxide. Im-IL catalysts were prepared by sol-gel method. The synthesis of cyclic carbonate from AGE and CO₂ was carried out in a batch autoclave reactor. Im-IL with shorter alkyl chain length showed the highest conversion of AGE, probably due to the steric hindrance for the formation of intermediate from the catalyst prepared by using longer alkyl chains and AGE. High temperature and high pressure were favorable for the conversion of AGE. Im-IL can be reused for the reaction up to two consecutive runs without any considerable loss of its catalytic activity.     

Catalytic performance of quaternary ammonium salts in the reaction of butyl glycidyl ether and carbon dioxide

The synthesis of cyclic carbonate from butyl glycidyl ether (BGE) and carbon dioxide was performed in the presence of quaternary ammonium salt catalysts. Quaternary ammonium salts of different alkyl group (C₃, C₄, C₆ and C₈) and anions (Cl⁻, Br⁻ and I⁻) were used for this reaction carried out in a batch autoclave reactor at 60–120 °C. The catalytic activity increased with increasing alkyl chain length in the order of C₃ < C₄ < C₆. But, the quaternary ammonium salt with longer alkyl chain length (C₈) decreased the conversion of BGE because it is too bulky to form an intermediate with BGE. For the counter anion of the tetrabutyl ammonium salt catalysts, the BGE conversion decreased in the order Cl⁻ > Br⁻ > I⁻. The effects of carbon dioxide pressure and reaction temperature on this reaction were also studied to better understand the reaction mechanism.     

Interlaboratory comparison of real-time PCR protocols for quantification of general fecal indicator bacteria

The application of quantitative real-time PCR (qPCR) technologies for the rapid identification of fecal bacteria in environmental waters is being considered for use as a national water quality metric in the United States. The transition from research tool to a standardized protocol requires information on the reproducibility and sources of variation associated with qPCR methodology across laboratories. This study examines interlaboratory variability in the measurement of enterococci and Bacteroidales concentrations from standardized, spiked, and environmental sources of DNA using the Entero1a and GenBac3 qPCR methods, respectively. Comparisons are based on data generated from eight different research facilities. Special attention was placed on the influence of the DNA isolation step and effect of simplex and multiplex amplification approaches on interlaboratory variability. Results suggest that a crude lysate is sufficient for DNA isolation unless environmental samples contain substances that can inhibit qPCR amplification. No appreciable difference was observed between simplex and multiplex amplification approaches. Overall, interlaboratory variability levels remained low (<10% coefficient of variation) regardless of qPCR protocol.     

Proximate Composition and Fatty Acid Profile of <Emphasis Type="Italic">Pongamia pinnata</Emphasis>, a Potential Biodiesel Crop

The chemical characteristics of Pongamia pinnata seeds, focussing on proximate composition and the fatty acid profile of its oil, are presented. The proximate composition of P. pinnata seeds was: 3.8% ash, 9.7% sugar, 7.07% protein, 24% oil, 10.7% free amino acids, and 0.24% free fatty acids. The oil was extracted from seeds by use of different solvents and the highest yield (29%) was obtained by use of n-hexane. Monounsaturated and polyunsaturated fatty acids accounted for 63.3 and 22.9%, respectively, of the seed oil. Oleic acid was the major fatty acid but a substantial amount of erucic acid was also detected; this was not reported in previous studies. The level of erucic acid and the presence of toxic flavonoids, for example karanjin, pongapin, and pongaglabrin, render the oil inedible according to WHO recommendations. However, low levels of saturated and polyunsaturated fatty acids with desirable cetane number and iodine value suggest potential for application as a biodiesel fuel.     

Screen printed novel ZnO/MWCNTs nanocomposite thick films

Zinc oxide and multiwall carbon nanotubes (ZnO/MWCNT) nanocomposites thick films were prepared via sol-gel screen printing procedure and followed by sintering at 550 °C. Thus, the prepared films were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), Ultraviolet–visible (UV–vis), Photoluminescence (PL), Fourier transform infrared (FTIR), Raman spectroscopy and Two-probe method. XRD analysis revealed (101) orientation for both ZnO and ZnO/MWCNT thick films with wurtzite structure. SEM studies confirmed the porous nature of ZnO film while ZnO/MWCNT films showed ZnO particles trapped in the porous MWCNT network and free from cracks. Reflectance spectroscopy showed direct transition with decreasing band gap whereas refractive index and absorption index showed appreciable variation within the band gap regime related to the change in crystallite size. FTIR profile approved the Zn–O stretching and presence of carboxylic CDC group. The PL spectrum of ZnO and ZnO/MWCNT thick films shows red shift and exhibits UV, blue and green emissions confirmed from CIE diagram. Raman spectrum shows that Raman phonons are shifted and dominated due to doping of MWCNT in ZnO matrix. Electrical properties were investigated using 2-probe method and showed a reduction in resistance on MWCNT incorporation. The novelty of current-work is the fabrication of ZnO/MWCNT through a low-cost screen printing process for the first time and the results exhibits that the bandgap of the deposited film is decreased, which in turn, play a significant role in enhancement of conductivity and colour emission for fabrication of low cost optoelectronics devices (LEDs) as compared with the pure ZnO film.