91 research outputs found

    Face Recognition Using Dct And Neural Micro-Classifier Network

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    Abstract— In this study, a proposed faces recognition methodology based on the neural micro-classifier network. The proposed methodology uses simple well known feature extraction methodology. The feature extraction used is the discrete cosine transformation low frequencies coefficients. The micro-classifier network is a deterministic four layers neural network, the four layers are: input, micro-classifier, counter, and output. The network provide confidence factor, and proper generalization is guaranteed. Also, the network allows incremental learning, and more natural than others. The proposed face recognition methodology was tested using the standard ORL data set. The experimental results of the methodology showed comparative performance

    Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions.

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    publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.publisher: Elsevier articletitle: Homogeneity of ball milled ceramic powders: Effect of jar shape and milling conditions journaltitle: Data in Brief articlelink: http://dx.doi.org/10.1016/j.dib.2016.11.070 associatedlink: http://dx.doi.org/10.1016/j.matdes.2016.06.118 content_type: article copyright: © 2016 The Authors. Published by Elsevier Inc.This paper contains data and supporting information of and complementary to the research article entitled "Effect of jar shape on high-energy planetary ball milling efficiency: simulations and experiments" (Broseghini et al.,) [1]. Calcium fluoride (CaF2) was ground using two jars of different shape (cylindrical and half-moon) installed on a planetary ball-mill, exploring different operating conditions (jar-to-plate angular velocity ratio and milling time). Scanning Electron Microscopy (SEM) images and X-Ray Powder Diffraction data (XRPD) were collected to assess the effect of milling conditions on the end-product crystallite size. Due to the inhomogeneity of the end product, the Whole Powder Pattern Model (WPPM, (Scardi, 2008) [2]) analysis of XRPD data required the hypothesis of a bimodal distribution of sizes - respectively ground (fine fraction) and less-to-not ground (coarse fraction) - confirmed by SEM images and suggested by the previous literature (Abdellatief et al., 2013) [3,4]. Predominance of fine fraction clearly indicates optimal milling conditions.The present work was partly supported by Fondazione Caritro, under Project No. 2013-0247 Mechanical activation to improve bioavailability and reduce adverse effects of drugs in the therapy of chronic diseases. NMP is supported by the European Research Council (ERC StG Ideas 2011 BIHSNAM n. 279985, ERC PoC 2015 SILKENE nr. 693670), by the European Commission under the Graphene Flagship (WP14 Polymer Composites, No. 696656)

    Structural Defects in Nanotechnology: Production, Characterization, Applications: Transport Properties in Mechanically Ground Nanocrystalline Ceramics & Hydrogen Storage in Metallic Hydrides

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    Structural defects play a major role in nanotechnology as they influence most properties, thus largely motivating the special interest in studying materials at the nano scale. The present Thesis work contributes to this broad and diversified research field with emphasis on the characterization of nanocrystalline ceramic materials and their lattice defects. In particular, main efforts were addressed to develop new and more comprehensive approaches to the study of nanocrystalline powders, combining different techniques for a better and deeper understanding of materials. The specific applications selected in this work are basically two: nanocrystalline fluorite as a promising ionic conductor and nanocrystalline magnesium hydride for hydrogen storage applications. Chapters II and III were dedicated to investigate nanocrystalline fluorite produced by two different methods: a bottom-up approach based on co-precipitation of Ca and F precursors yielding loosely bound nanocrystals, and a popular top-down approach, high energy ball milling, giving nanocrystals of comparable sizes but strongly agglomerated and densely populated with dislocations. As a major achievement reported in this part of the Thesis work, a new approach was proposed and tested for the simultaneous modelling of X-ray Diffraction (XRD) peak profiles and solid state NMR spin-lattice relaxation data. With the valuable support of Transmission Electron Microscopy (TEM), this work offers a new understanding of the complex defect structure of nanocrystalline fluorite, and is also a demonstration of the power of combining different techniques in a consistent way. One of the most debated aspects of nanotechnology concerns the stability of the nanostructure, and the mechanisms of defect annealing and grain growth with temperature. This topic was the object of chapter V, dedicated to study the influence of lattice defects on the grain growth kinetics of nanocrystalline fluorite. This chapter was preceded by chapter IV, on the furnace recently installed at the MCX beamline for in-situ high temperature fast data collection; besides providing useful details for the in-situ study on nanocrystalline fluorite shown in the following chapter, the activity reported in chapter IV is a tangible sign of the special involvement during the Thesis work in supporting standard operation as well as development of the ELETTRA beamline MCX. The growth kinetics was studied on two samples, among those discussed in Chapter III, with comparable crystalline domain size but drastically different lattice defect content, so to highlight the role lattice defects – dislocations in this case – in the growth process. 14 Last two chapters (chapter VI and VII) were dedicated to nanocrystalline magnesium hydride, and how the performance, in particular the hydrogen desorption kinetics, can be improved by adding a nanocrystalline tin oxide. Besides general aspects on phase composition of the system and hydrogen storage capability, the work also addressed the problem of obtaining activation energy values in the thermal decomposition of magnesium hydride powders, presenting an interesting review of results given by the most known and well-assessed TG-MS coupled measurements, with details on the use of different equations of the literature on thermal analysis. Although research work can rarely be considered as finished, a sound conclusion of this Thesis work is toward the use of different characterization techniques, also within the same data analysis procedure, to support a better, and more reliable investigation of nanomaterial properties

    A literature review on collaborative caching techniques in MANETs: issues and methods used in serving queries

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    Collaborative cache management in Mobile Ad Hoc Networks (MANETs) environment is considered as an efficient technique to increase data accessibility and availability, by sharing and coordination among mobile nodes. Due to nodes’ mobility, limited battery power and insufficient bandwidth, researchers addressed these challenges by developing many different collaborative caching schemes. The objective of this paper is to review various collaborative caching techniques in MANETs. Collaborative caching techniques are classified by methods used in serving queries, such as: hop-by-hop discovering, broadcasting messages, flooding, and query service differentiation. This review reveals that techniques utilizing hop-by-hop methods have better performance compared to others, especially techniques using additional strategies

    Molecular Characterization of Methicillin Resistant Staphylococcus aureus in West Bank-Palestine

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    Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a public health threat and a major cause of hospital-acquired and community-acquired infections. This study aimed to investigate the genetic diversity of MRSA isolates from 2015 to 2017 and to characterize the major MRSA clones and anti-biogram trends in Palestine. Methodology: Isolates were obtained from 112 patients admitted to different hospitals of West Bank and East Jerusalem, originating from different clinical sources. Antibiotic susceptibility patterns, staphylococcal chromosomal cassette mec (SCCmec) typing, and Staphylococcus aureus protein A (spa) typing were determined. Also, a panel of toxin genes and virulence factors was studied, including: Panton-Valentine Leukocidin (PVL), ACME-arcA, Toxic Shock Syndrome Toxin-1 (TSST-1), and Exfoliative Toxin A (ETA). Results: Of the 112 confirmed MRSA isolates, 100% were resistant to all β-lactam antibiotics. Resistance rates to other non- β-lactam classes were as the following: 18.8% were resistant to trimethoprim-sulfamethoxazole, 23.2% were resistant to gentamicin, 34.8% to clindamycin, 39.3% to ciprofloxacin, and 63.4% to erythromycin. All MRSA isolates were susceptible to vancomycin (100%). Of all isolates, 32 isolates (28.6%) were multidrug- resistant (MDR). The majority of the isolates were identified as SCCmec type IV (86.6%). The molecular typing identified 29 spa types representing 12 MLST-clonal complexes (CC). The most prevalent spa types were: spa type t386 (CC1)/(12.5%), spa type t044 (CC80)/(10.7%), spa type t008 (CC8)/(10.7%), and spa type t223 (CC22)/(9.8%). PVL toxin gene was detected in (29.5%) of all isolates, while ACME-arcA gene was present in 18.8% of all isolates and 23.2% had the TSST-1 gene. The two most common spa types among the TSST-1positive isolates were the spa type t223 (CC22)/(Gaza clone) and the spa type t021 (CC30)/(South West Pacific clone). All isolates with the spa type t991 were ETA positive (5.4%). USA-300 clone (spa type t008, positive for PVL toxin gene and ACME-arcA genes) was found in nine isolates (8.0%). Conclusions: Our results provide insights into the epidemiology of MRSA strains in Palestine. We report a high diversity of MRSA strains among hospitals in Palestine, with frequent SCCmec type IV carriage. The four prominent clones detected were: t386-IV/ CC1, the European clone (t044/CC80), Gaza clone (t223/CC22), and the USA-300 clone (t008/CC8).We greatly acknowledge all hospitals that provided us with the isolates and responded to our contact. Special thanks to Al- Makassed Islamic Charitable Hospital/microbiology laboratory in East Jerusalem; including; Mr. Sabri Baragthithi and Mrs. Suzan Idkaidek. Also, many thanks to Mr. Mamoun Obeideia from the Palestine Medical complex and Mrs. Namir Sabri from the Red Crescent Society in Jerusalem. Many special thanks to Dr. G. Regev-Yochay and Asaf Biber from Sheba Medical Center, assistance. This data were presented as partial requirements for a master degree of Microbiology and Immunology/Al-Quds University under supervision of KA

    Predictive Modeling of Oxygen Transmission Through Micro-Perforations for Packaging Applications

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    Methods for creating precise perforations in respiring produce packaging are being increasingly adopted. Knowledge of oxygen transfer through perforated packaging and oxygen distribution in packages is necessary for successful packaging design of fresh produce. An approach to modeling perforated packaging performance was developed using a cylindrical chamber with precision perforations using Fick’s second law. The model was simulated using two techniques including Finite Element Method (FEM) using commercially available software and Finite Volume Method (FVM) through programming. Perforations were approximated as a source term in the second method. Both simulation techniques showed trends similar to experimental data

    Valorization of waste biomass to biofuels for power production and transportation in optimized way: a comprehensive review.

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    Fossil fuels are primary sources for energy production. Increased dependence on fossil fuels has resulted in increased environmental issues demanding alternative sources. Bioenergy is becoming a popular alternative energy source due to its positive environmental impact and the availability of renewable sources. However, the availability of renewable energy sources in the energy sector currently contributes to about 14%. Biofuels are preferred due to its sustainability, eco-friendly approach, and low-cost raw materials, making it an efficient technique for energy production. This article provides the fundamental and applied concepts for on conversion processes of biomass to biofuels, such as combustion, pyrolysis, fermentation, gasification, and anaerobic digestion along with their role in the green economy. Different physical characteristics of biomass resources are important and contribute to determining their potential for producing biofuels. Herein, LCA, its techno-economic importance, and the role of biomass in green economy are explained. Varying compositions and properties of different types of biomass resources, including lignocellulosic feedstocks, agriculture and forest residue, municipal solid waste, food waste, and animal manure as potential biomass resources, have been discussed. The article explains the strengths and weaknesses of different thermochemical conversion techniques and their current input toward scalar applications and commercialization

    Effect of Plasticizer on Oxygen Permeability of Cast Polylactic Acid (PLA) Films Determined Using Dynamic Accumulation Method

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    Polylactic acid (PLA) is becoming an increasingly important biopolymer for packaging applications. PLA brittleness limits its applicability. This study evaluated PLA properties with increasing amounts of added polyethylene glycol (PEG) plasticizer. Oxygen transmission rate (OTR) of cast films was determined using the newly available Dynamic Accumulation (DA) method. Arrhenius temperature sensitivity of OTR and polymer Permeability was also determined. Permeability of neat PLA is 4.848 ml mm (STP)/m2 s kPa; hence, 4.84 ml mm (STP)/m2 s kPa, 4.07 ml mm (STP)/m2 s kPa and 5.42 ml mm (STP)/m2 s kPa by adding PEG 1 %, 5% and 10% respectively. The main conclusion from this work is increasing PEG will enhance the PLA permeability number but excess PEG in PLA film will decrease the permeability number
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