Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 5 )

2019 ( 784 )

2018 ( 990 )

2017 ( 961 )

Custom range...

Search Results: 1 - 10 of 601548 matches for " R. A. "
All listed articles are free for downloading (OA Articles)
Page 1 /601548
Display every page Item
An Approach for Content Retrieval from Web Pages Using Clustering Techniques  [PDF]
R. Manjula, A. Chilambuchelvan
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.79230
Abstract: Mining the content from an information database provides challenging solutions to the industry experts and researchers, due to the overcrowded information in huge data. In web searching, the information retrieved is not an appropriate, because it gives ambiguous information for the user query, and the user cannot get relevant information within the stipulated time. To overcome these issues, we propose a new methodology for information retrieval EPCRR by providing the top most exact information to the user, by using the collaborative clustered automated filter which makes use of the collaborative data set and filter works on the prediction by providing the highest ranking for the exact data retrieved. The retrieval works on the basis of recommendation of data which consists of relevant data set with highest priority from the cluster of data which is on high usage. In this work, we make use of the automated wrapper which works similar to the meta crawler functionality and it obtains the content in the semantic usage data format. Obtained information from the user to the agent will be ranked based on the Enabled Pile clustered data with respect to the metadata information from the agent and end-user. The information is given to the end-user with the top most ranking data within the stipulated time and the remaining top information will be moved to the data repository for future use. The data collected will remain stable based on the user preference and works on the intelligence system approach in which the user can choose any information under any instances and can be provided with suitable high range of exact content. In this approach, we find that the proposed algorithm has produced better results than existing work and it costs less online computation time.
Efficient Estimation of Distributional Tail Shape and the Extremal Index with Applications to Risk Management  [PDF]
Travis R. A. Sapp
Journal of Mathematical Finance (JMF) , 2016, DOI: 10.4236/jmf.2016.64046
Abstract: Abundant evidence indicates that financial asset returns are thicker-tailed than a normal distribution would suggest. The most negative outcomes which carry the potential to wreak financial disaster also tend to be the most rare and may fall outside the scope of empirical observation. The difficulty of modelling these rare but extreme events has been greatly reduced by recent advances in extreme value theory (EVT). The tail shape parameter and the extremal index are the fundamental parameters governing the extreme behavior of the distribution, and the effectiveness of EVT in forecasting depends upon their reliable, accurate estimation. This study provides a comprehensive analysis of the performance of estimators of both key parameters. Five tail shape estimators are examined within a Monte Carlo setting along the dimensions of bias, variability, and probability prediction performance. Five estimators of the extremal index are also examined using Monte Carlo simulation. A recommended best estimator is selected in each case and applied within a Value at Risk context to the Wilshire 5000 index to illustrate its usefulness for risk measurement.
Schooling for Digital Citizens  [PDF]
Najah A. R. Ghamrawi
Open Journal of Leadership (OJL) , 2018, DOI: 10.4236/ojl.2018.73012
Abstract: This study explored the Lebanese teachers’ perceptions regarding their knowledge, practice and self-efficacy pertaining to digital citizenship. Data were collected from 378 teacher participants from public schools in Beirut, Lebanon. The study used mixed methods employing an adapted form of Rible’s (2015) survey on digital citizenship, alongside a structured focus group interview with 8 teachers drawn randomly from the pool of participant schools. Findings suggest that Lebanese teachers have dispersed and unbalanced perceptions of the concept of digital citizenship, limited practice, and recessive self-efficacy. The study recommends that successful endeavours towards establishing efficient digital citizenship should start with the reconstruction of teachers’ knowledge and level of awareness pertaining to digital citizenship.
Natural Attenuation Capacity Indicators for Groundwater Remediation to the Northeastern Cairo  [PDF]
A. A. Embaby, M. A. Sadek, R. A. Rayan
Journal of Geoscience and Environment Protection (GEP) , 2017, DOI: 10.4236/gep.2017.54012
Abstract: The natural attenuation capacity of groundwater is considered to be an important factor for remediation purpose, it is also important for surveying suitability in the early phases of siting hazardous facilities. The present work has been devoted to explore the natural attenuation capacity of the groundwater system northeast Cairo. Some indicators (hydrogeological, hydrochemical and isotopic) have been insighted to explore the system retardability against contaminant dispersion. Groundwater flow and contaminant transport have been pointed out using GOD index which varied from 0.04 to 0.28 reflecting high protectability. The isotopic contents (18O, 3H, and 14C) showed a general comply with the GOD index and helped to delineate the sectors of high contaminate attenuation ability. Kelly index inferred significantly high adsorption potential on the aquifer clay content. The calcite and dolomite tend to precipitate on the aquifer contact providing a chance for specific contaminants to coprecipitate. The Eh-pH relation of the studied groundwater samples indicates high oxidation conditions and openness of the system. The attenuation capacity has been determined mathematically, it assumes the dispersive, advective, sorptive, and degradative processes acting on a solute in a one-dimensional flow system. The value of attenuation capacity increases by decreasing groundwater velocity and completely vanishes at a certain high velocity; determined for the relevant radioactive contaminants.
Preparation of Perfluorinated Surfactant Activates for Antifouling Paints  [PDF]
A. Bacha, R. Méghabar
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2012, DOI: 10.4236/jsemat.2012.24041
Abstract: Antifouling paints are the most reliable way to prevent biofouling of submerged surfaces. The high toxicity of organotin paints, prompted us to look for ideas to develop paints that do not present environmental risks. In this work, we prepare a painting by a modification of acrylic acid monomer containing a free carboxyl group. The biocide that is selected is the perfluorinated chain with eight carbons. Chemical modifications of the resins are made through a radical reaction. The magnitudes of changes are monitored by proton nuclear magnetic resonance NMR, gel permeation chromatography (GPC) and the light scattering (LS) at a fixed angle 90℃. The glass transition temperature of the surfactant is obtained by the differential scanning calorimetry (DSC). The antifouling properties of the paint are followed by exposure of panels to the marine environment by visual observation.
Clay Minerals as Climate Change Indicators—A Case Study  [PDF]
A. R. Chaudhri, Mahavir Singh
American Journal of Climate Change (AJCC) , 2012, DOI: 10.4236/ajcc.2012.14020

The clay mineralogy of the Late Pliocene-Early Pleistocene Pinjor Formation of the type area, northwestern Himalaya, India has been investigated to understand the paleoclimatic conditions and paleotectonic regime prevailing in the frontal Himalayan terrain during 2.5 Ma to 1.7 Ma. The clay minerals were investigated by X-ray diffraction analysis and scanning electron microscope studies. Study of the oriented aggregates of 47 representative clay samples of the Pinjor Formation of the type area reveals that illite is the most dominant mineral followed by chlorite, kaolinite, vermiculite and mixed layer clay minerals. The distribution of the clay minerals in the three lithostratigraphic units of the Formation, namely the Kona Clay Member, the Tanda Bhagwanpur Wacke Member and the Chauki Nadah Pebbly Bed Member which are well exposed along the Berwala-Mandhna section, the Kona-Karaundanwala section and the Ghaggar River-Chauki Nadah section, is nearly uniform suggesting thereby the prevalence of similar sedimentation environments in the Himalayan foreland basin. The presence of illite and kaolinite suggests their derivation from crystalline rocks containing felspar and mica as also from pre-existing soils and sedimentary rocks. Further, the paleoclimatic conditions were moderate. Presence of chlorite suggests the weathering of intermediate and basic crystalline rocks and low grade metamorphic rocks in the positive areas. The presence of kaolinite in the Pinjor Formation is mainly attributed to the weathering and subsequent leaching of the mineral from granitic and basic rocks in the hinterland. Vermiculite has been mainly formed by weathering and transformation of biotite. Warm and humid climatic conditions prevailed for a major part during the deposition of the detritus which favored weathering and transformation of minerals. During the terminal phase of sedimentation there was renewed tectonic activity which had a significant impact on climate as precipitation and mechanical weathering rates increased substantially. Post 1.7 Ma there was a marked shift in temperature patterns and subsequent cooling of the landmass,

Small-Angle X-Ray Scattering of Amorphous Germanium: Numerical Modeling  [PDF]
R. Ben Brahim, A. Chehaidar
Advances in Materials Physics and Chemistry (AMPC) , 2013, DOI: 10.4236/ampc.2013.31A003

The present work deals with a detailed analysis of the small-angle X-ray scattering of nanoporous atomistic models for amorphous germanium. Structures with spherical nanovoids, others with arbitrarily oriented ellipsoidal ones, with monodisperse and polydisperse size distributions, were first generated. After relaxing the as-generated structure, we compute its radial distribution function, and then we deduce by the Fourier transform technique its X-ray scattering pattern. Using a smoothing procedure, the computed small-angle X-ray scattering patterns are corrected for the termination errors due to the finite size of the model, allowing so, for the first time at our best knowledge, a rigorous quantitative analysis of this scattering. The Guinier’s law is found to be valid irrespective of size and shape of the nanovoids over a scattering vector-range extending beyond the expected limit. A weighted combination of the Guinier’s forms accounts for well the nanovoid size distribution in the amorphous structure. The invariance of the Q-factor and its relationship to the void volume fraction are also confirmed. Our findings support then the quantitative analyses of available small-angle X-ray scattering data for amorphous germanium.

“Choke” Chuck Palahniuk Book Review  [PDF]
ar? Tu?rul Mart
Advances in Literary Study (ALS) , 2013, DOI: 10.4236/als.2013.12005
Abstract: Victor Mancini, the protagonist, did not have a happy childhood as his mother was constantly committing crimes; therefore, she was mostly in jail. Victor was mostly brought up by other families so he grew up without family affection. Today Victor is in his twenties, but he has got problems. Victor feels lonely and he cannot forget his past. He tries to forget his loneliness and has become sex addicted. He intentionally chokes while eating in expensive restaurants, and there is always someone who saves him. A close rela-tionship between him and his saver starts. His saver even sends him money. But Victor is not doing this for money. Another problem he has: Victor thinks he is Jesus Christ and he likes this idea because this will help him to realize he could be a nice guy. Victor never means to deceive other people. He does all these things to get attention of people. He is searching for love, he is seeking for affection.
Nucleocytoplasmic Gynodioecy  [PDF]
R. Doroteo, J. A. Vargas
Applied Mathematics (AM) , 2013, DOI: 10.4236/am.2013.412226

We study the evolution of a gynodioecious species under mixed-mating through a nucleocytoplasmic male sterility model. We consider two cytoplasmic types and a nuclear locus with two alleles. Here, the interaction between one cytoplasmic type and a recessive nuclear male-sterility factor gives rise to only one female genotype, while the remaining types correspond to hermaphroditic plants. We include two fitness paramaters: the advantageous female fitness t of females relative to that of hermaphrodites; and a silent and dominant cost of restoration, that is, a diminished fitness for plants carrying a dominant restorer gene relative to that of hermaphrodites. The parameter related to the cost of restoration is assumed to be present on outcrossing male fertility only. We find that every population converges to a stable population. We also determine the nature of the attracting stable population, which could be a nucleocytoplasmic polymorphism, a nuclear polymorphism or another population with some genotypes absent. This depends on the position of t with respect to critical values expressed in terms of the other parameters and also on the initial population.

Size Analysis of the Late Pliocene-Early Pleistocene Upper Siwalik Sediments, Northwestern Himalaya, India  [PDF]
Mahavir Singh, A. R. Chaudhri
International Journal of Geosciences (IJG) , 2013, DOI: 10.4236/ijg.2013.48106

Size analysis of the Late Pliocene-Early Pleistocene Upper Siwalik sediments comprising the Pinjor Formation in the type area and adjoining regions reveals that the sediments are bimodal to polymodal in nature, medium to fine grained and are moderately sorted. The inclusive graphic standard deviation and moment standard deviation values suggest the deposition of sediments in shallow to moderately deep fluvial agitated water. The log probability plots reveal that saltation mode is the dominant mode of transportation of detritus. The sediments are continental in character and are derived from crystalline, metamorphic and sedimentary rocks of the Himalaya exposed to the North of the type area Pinjor.

Page 1 /601548
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.