Archives-August 2013

The need of automatic classification of text has become very crucial with the rampant growth in the amount of information available in today’s world of fast digitization. Text classification (also called text categorization) is the process of classifying documents into pre-defined categories. A number of techniques have been devised over the ages for text classification. One such technique for text categorization is Support Vector Machine (SVM). SVMs are binary classifiers which classifies text into exactly two categories. Many researchers have found that SVM works reasonably well. In this paper, this technique is used for classifying a set of documents. Five models have been created from five different domains and data from each domain are classified using these models and the accuracy is recorded.

With the huge upsurge of information in day-to-day’s life, it has become difficult to assemble relevant information in nick of time. But people, always are in dearth of time, they need everything quick. Hence clustering was introduced to gather the relevant information in a cluster. There are several algorithms for clustering information out of which in this paper, we accomplish K-means and K-Medoids clustering algorithm and a comparison is carried out to find which algorithm is best for clustering. On the best clusters formed, document summarization is executed based on sentence weight to focus on key point of the whole document, which makes it easier for people to ascertain the information they want and thus read only those documents which is relevant in their point of view.

The paper presents the modeling, simulation & analysis of Speed Controller for a Brushless DC Motor. Performance comparison between a position sensor and sensorless based speed control is also presented in the paper. Hall effect Sensors have been used for position sensing and back emf based method has been used for determining the position of rotor in position sensorless scheme. The speed controller has been implemented by incorporating PI controller and hysteresis current controller in MATLAB Simulink. Hysteresis current controller was used to generate PWM pulses for inverter switches. IGBT based inverter was used for conversion of DC power to AC power.

This paper attempted to fit an appropriate probability density function to available crime data in Nigeria by using the Pearson System of Distribution Approach. Rising crime rates have necessitated the need to model adequately crime occurrences to enhance effective management and control. Aggregated dataset of crime rates from 1994 to 2003 were used to estimate the parameters of the selected density functions from the Pearson system and for the goodness of fit test. Results showed that the Four Parameter Gamma density function was the most suitable for the data under study. This study has revealed the potentials of probability density functions in crime prevention and control.

This paper deal with the ecology of anopheline mosquitoes in Tehsil Sironj and Lateri of district Vidisha. Mosquito sampling took place surface water in the tah. Sironj stream were collected at 2- week intervals during August 2007 to July 2008. During the survey, it was noticed that permanent breeding ground such as ditches, cesspool, sewas, ponds and dam where same breeding ground where mosquito species laele there x qulex and aides mosquito breeds in polluted water all transmission water where they can with strand desiccation it was also noted that varies mosquito species used the same water bodies over a period of time.

The zebrafish is an extremely dynamic organ in which follicles undergo asynchronous development. The oocytes of Zebrafish ovary are observed in various phases. The oocyte development of zebrafish was divided into four stages (primary growth, cortical alveolus-previtellogenic, vitellogenic and mature oocyte). Zebrafish follicles contain only a single layer of granulosa cells that are separated from the oocyte by the vitelline envelope (zona radiata). The follicular epithelium and theca of oocytes in zebrafish differentiates during the primary growth phase.Histological analysis revealed that the zona radiata is formed during the vitellogenic growth stage. Specializations associated to the outher layer of the zona radiata may be related to the egg’s adherence to the substrata. Follicular cell and oocyte cytological characteristics don’t differ from those described in other teleosts species.

This research will examine synthesis of single-wall carbon nanohorns (SWCNHs) by dielectrophoresis (DEP). This will involve electrokinetic synthesis method which will produce a SWCNHs sensor. In dielectrophoresis (DEP), the carbon particles will be subjected to a non-uniform electric field and thus a force will be exerted on the particles. The materials are dielectrically polarized with electrokinetic motion in non-uniform electric fields. The region of higher electric field will attract the nanoparticles due to positive DEP force. The carbon nanoparticles are then trapped in the electrode gap and thus form an electrical connection to the external measuring circuit. This method provides a fast, simple and low cost fabrication of nanomaterial-based sensors based on a bottom-up approach.

In this paper, we present a counter-example for the stability of reciprocal type functional equation controlled by product of different powers in singular case.

Natural products remain either the source of the inspiration for a significant proportion of the new small molecule chemical entities introduced as drugs. Actinomycetes are the largest antibiotic producing genus in the microbial world discovered so far. The number of antimicrobial compounds reported from the different species of actinomycetes per year has increased almost exponentially for about two decades. As marine environment are different from terrestrial it is concluded that marine actinomycetes might produce various types of novel bioactive compounds and enormous antibiotics. The objectives of this study is to isolate actinomycetes from salt pans of Marakanam to optimize and screen the production of secondary metabolites from the isolated, two isolated selected actinomycetes and to the check the antimicrobial activity of these metabolites against pathogens. Out of 30 actinomycetes isolates Ros11 and Ros25 were screened and characterized based on antimicrobial properties. The secondary metabolites were extracted from Ros 11 and Ros 25 by chemical solvents, ethyl acetate and acetone. Using well diffusion method it was observed that secondary metabolites of Ros 25 formed maximum inhibition zones, 10mm, 12mm and 15mm against Staphylococcus aureus and fungal pathogens Aspergillus niger and Aspergillus fumigates, respectively. The Ros 25 isolate could be the better candidate for the production of antibacterial and antifungal compounds.

Hepatoprotective activity and antioxidant status of ethanolic extracts of 200,400,600 mg/kg of Alpinia purpurata rhizome was evaluated against Carbon tetrachloride (CCl4) in rats. Acute and short-term toxicity studies were performed initially in order to ascertain the safety of ethanolic extracts of Alpinia purpurata rhizome. After 48 hrs of CCl4 induced, the extract was administered daily for 15 days. After administration of the last dose followed by 18 h fasting, rats were then sacrificed for observation of hepatoprotective activity. The effect of ethanolic extracts of Alpinia purpurata on the CCl4 treated rats. Ethanolic extract showed significant (p<0.05) hepatoprotective effect by lowering the serum levels of various biochemical parameters such as serum glutamic oxaloacetate transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT), alkaline phospatase (ALP), total bilirubin (TBL), total cholesterol (CHL) in the selected model and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. These biochemical observations were in turn confirmed by histopathological examinations of liver sections and are comparable with the standard hepatoprotective drug Silymarin (25.0 mg/kg body weight, p.o) which served as a positive control. Treatment with ethanolic extracts of Alpinia purpurata decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase. The ethanolic extracts of Alpinia purpurata rhizome exhibited hepatoprotective effect by modulating lipid peroxidation and augmenting antioxidant defense system in CCl4 treated rats.