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In this work, a novel power conversion structure for grid-connected photovoltaic applications is presented. This structure is based on a Diode clamped multilevel inverter. The configuration of the PV system is based on the multi-string technology and the maximum power point is obtained using PSO Algorithm. The output of the MPPT tracker controls the duty cycle of the boost converter. To control this power converter, SVPWM based modulation technique is implemented. The proposed system operation was simulated using the MATLAB/Simulink power system toolbox and are furnished to verify the efficiency of this method.

Abstract The levels of Organochlorine Pesticides (OCPs) in plastic resin pellets were determined with the objective of assessing the status of OCP pollution in the marine ecosystem of selected beaches in Ghana (namely Art Centre, Sakumono, Osu Castle, Labadi, Korle-Gonno, Independence Square and Tema Mighty beaches). The plastic pellets were subjected to Soxhlet extraction and the extracts analyzed using Gas Chromatograph coupled with electron capture detector. High concentrations of Dichlorodiphenyltrichloroethane compounds (DDTs) were recorded followed by Hexachlorocyclohexane (HCHs), Chlordane compounds (CHLs), Hexachlorobenzene (HCB), Aldrin, Dieldrin, Endrin (DRINs), alpha-endosulphan, beta-endosulphan, endosulphan sulphate (Endosulphans) and Methoxychlor. Analysis of the virgin pellets recorded no organochlorine pesticides present. However, plastic pellets collected from all seven beaches were found to contain OCPs with the highest recorded on the Art Centre beach with a total OCP concentration of 106 ng/g. Plastic pellets collected on the Labadi beach recorded the lowest OCPs with a concentration of 20.2 ng/g. The accumulation of OCP residue on the plastic resin pellets suggests that it can be used as a tool for monitoring marine pollution. Key words: Plastic resin pellets, organochlorine pesticides, beaches, concentration, Ghana.

The aim of present research is to determine and prioritize criteria and scales of evaluating cohesive training systems. Present paper attempts to provide a paradigm for better devising of universities' cohesive training systems by identifying such scales. In terms of its aim, this research is an applied one and in terms of data collection method, it is descriptive and survey one. Its population includes elite training experts in the colleges and institutes affiliated to University of Tehran. It attempts to study domestic and foreign papers and to identify criteria and scales for evaluating cohesive training systems. Library method is used to gather information on theoretical basics, literature and to identify aspects and scales. Identified aspects include: content, flexibility, organizational structure, usage convenience, usage services and apparent form. To prioritize identified aspects and scales, the opinions of elite training experts in University of Tehran are used. Data gathering tool was questionnaire. Data were analyzed by AHP method and Expert Choice software. According to research findings, the relative supremacy of content was 0.362; flexibility, 0.225; organizational structure, 0.155; usage convenience, 0.115, usage service, 0.087; and apparent form, 0.056. So, one can say that the importance of identified aspects to evaluate cohesive training systems in terms of priority is content, flexibility, organizational structure, usage convenience, usage services and apparent form.

In the fashion business, privately owned brick-and-mortar fashion boutiques in the United States face the challenge of competing with online retailers who usually have low overheads and inventories. The knowledge and awareness of the changing marketing landscapes responsible for the decline in the survival rate of traditional or brick-and-mortar fashion boutiques may be essential to traditional and online entrepreneurs, to increase adaptability and business sustainability. Grounded in the general systems theory, the research conducted through the invocation of a qualitative multiple case study, entailed the exploration of strategies used by successful brick-and-mortar fashion boutique owners in contending with the online retailers. Interviews constituted the means for data collection and involved 5 brick-and-mortar fashion boutique owner participants, who operated retail fashion businesses in the southeast region of the United States. The successful existence of the business for more than 5 years, while participation criteria in the study, also indicated merit in studying success in traditional fashion retailing. The primary data from interviews were analyzed and triangulated with credible secondary sources such as information and reports from the U. S. Small Business Administration, U. S. Census Bureau, and fashion industry sources. From a thematic analysis of the interview data, the three themes that emerged from the data analysis were the importance of business success of marketing strategies, cognizance of fashion trends, and the role of customer preference in economic success. The potential knowledge from the utilization of the study results may serve to increase the success rates of traditional and online fashion startups and possibly endow these businesses with the adaptabilities and strategies capabilities in the inevitable greater transformation to an online business world.

Work on global warming is expected to have significant impacts on conditions affecting agriculture, including temperature, carbon dioxide, glacial run off, precipitation and the interaction of these elements has been reviewed in this article. To a large extent, the overall effect of climate change will depend on the balance among these factors. Assessment of the effects of global climate changes on agriculture will help to properly anticipate and adapt farming systems to maximize agricultural production. There is exponential rise in atmospheric carbon dioxide. Atmospheric concentration of carbon dioxide was 270 ppm during pre-industrial period and human activities have added more than 100 ppm and it has reached 380 ppm with the rate of rise as high as 1.8 ppm per year. With this exponential rise in carbon dioxide, its concentration will double by the middle of 21st century. The effects of an increase in carbon dioxide would be higher on C3 plants (such as wheat) than on C4 plants (such as maize), as the former is more susceptible to carbon dioxide deficit. Increased CO2 leads to fewer stomata development in case of plants which results in less water usage. It is estimated that under optimum conditions of temperature and humidity, the yield increase could reach 36 % if the levels of CO2 are doubled. A large number of stress responsive genes have been cloned and sequenced from a number of crop plants. A common feature of many stress induced proteins is that their transcripts are induced not only by stress but also by (ABA) abscisic acid. It implies that there is a general role for ABA in the signal transduction pathway i. e. from sensing of the environmental stress and thereby leading to gene expression.

In this paper we investigate the problem of separation of human voice from a mixture of voice and different music instruments. The human voice may be a part of singing voice in a song or it may be a part of some news broadcasted by a channel and it contains background music. The final outcome of this work is a file containing only vocals. In our approach we consider stereo audio for separation. We process the signal in time frequency domain. In our method of blind source separation we processed the input stereo audio file in the form of frames, windowed them and then applied discrete Fourier transform (DFT) on signal. Then the signal is masked for de-mixing purpose using time frequency filters and non-zero DFT coefficients that are estimated as a part vocals are selected and signal is reconstructed by overlap add (OLA) method to get the final output signal containing only vocals.

L1-minimization solves the minimum L1-norm solution to an underdetermined linear system. It has recently received much attention, mainly motivated by the new compressive sensing theory that shows that under certain conditions an L1-minimization solution is also the sparsest solution to that system. In this paper an L1 minimization algorithm is proposed for solution of Dual Tone Multiple Frequ-ency (DTMF) reconstruction problems. In the method of Compressive sensing, a raw signal or image can be regarded as a vector which can be represented as a linear combination of certain basis functions. The discrete cosine transform (DCT) has been used as the basis function in the proposed algorithm. This algorithm considers only 500 samples and reconstructs the original signals exactly without any distortion. The compressed DTMF signal is estimated using DTMF decoder with the help of Goertzel algorithm, the popularity of which lies in the small number of points at which the DFT is estimated. We compare with the existing algorithms such as FFT and Goertzel algorithms. The results show the effectiveness of the proposed algorithm.

This paper deals with the geotechnical investigation of Geopathic Stress Zone. The energy from the earth at specific locations that have the ability to change the normal functioning of human system is called Geopathic Stress. In Structures, soil is an important component; change in Geotechnical Properties of the soil affects the stability of the structure. Experimental investigations on soil at Geopathic Stress Zone reveal that there is change in the properties of soil, due to such energies emitted by the earth, 30% of accidents take place. Investigations carried out by the researchers at mysterious accidental spots on Mumbai-Pune expressway has confirmed accidents occur due to existence of Geopathic stress, but there is no geotechnical investigations carried out on such accidental spots. This paper aims at finding out the change in soil properties due to presence of Geopathic Stress Zone. The conclusions are justified by carrying out different tests on soil such as, “determination of water-content, specific gravity, density, plastic and liquid limits, conductivity, electrical Resistivity and pH value.” The variation in the values of the Geotechnical Properties of soil at Geopathic stress zone is remarkable.

The various processing treatments like soaking, germination, boiling, steaming, roasting and fermentation are known to affect the chemical composition and improve the nutritive value of foods. Hence the present study was planned with the objectives to optimize the processing conditions and to study the effect of optimized conditions on total polyphenol content, antioxidant activity and FTIR spectra of kodo millet. The optimum time for soaking, boiling, steaming, roasting, germination and fermentation was determined by analysing the changes in moisture content, equivalent diameter, bulk density, reducing sugar and total sugar content. The optimally processed kodo millet was analysed for its total polyphenol content, antioxidant activity and FTIR spectra for identification of unknown polyphenolic compounds. Result revealed that kodo millet could be soaked for 76-78 hours, boiled/steamed for 25-30 minutes, roasted for 15-20 minutes, fermented for 48 hours at 37°C and germinated for 72 hours at 37°C and 50% RH optimally. The various processing methods significantly affected the total polyphenol content. Among the processed samples, the highest polyphenol content and antioxidant activity was noted in germinated and boiled grain respectively. FTIR spectral analysis revealed the presence of polyphenolic compounds especially with mono substituted benzene ring in all processing conditions.

A geoelectric investigation involving sixteen vertical electric soundings with maximum current electrode spacing of 650m was carried out at Obiaruku, Delta State, Nigeria and environs. This was aimed at determining the effect of seasonal variations of aquifer characterization and resistivity data. The resistivity data got from the survey is interpreted by curve matching and computer iteration techniques where the geological model parameters and curves were obtained. Three to six geological layers were observed within the whole locations. The results show that there was a slight difference in the apparent resistivity values between wet and dry seasons which could be attributed to the degree of wetness (especially the topsoil) experienced during the rainy season. The aquifers, number of layers, curve type and shape, layer thicknesses are approximately the same values for both rainy and dry seasons.