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Chinese Physics B 2016年第8期25卷 103-112页

作者： Parvin R Parvin f Ali m S Islam A K m A Department of Physics Rajshahi University Rajshahi-6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International Islamic University Chittagong 154/A College Road Chittagong-4203 Bangladesh

The electronic properties（fermi surface,band structure,and density of states（DOS）） of Al-based alloys Alm3（m=Zr and Cu） and AlCu2Zr are investigated using the first-principles pseudopotential plane wave method within the generalized gradient approximation（GGA）.The structural parameters and elastic constants are evaluated and compared with other available ***,the pressure dependences of mechanical properties of the compounds are *** temperature dependence of adiabatic bulk modulus,Debye temperature,specific heat,thermal expansion coefficient,entropy,and internal energy are all obtained for the first time through quasi-harmonic Debye model with phononic effects for T = 0 K-100 *** parameters of optical properties（dielectric functions,refractive index,extinction coefficient,absorption spectrum,conductivity,energy-loss spectrum,and reflectivity） of the compounds are calculated and discussed for the first *** reflectivities of the materials are quite high in the IR-visible-UV region up to ~ 15 eV,showing that they promise to be good coating materials to avoid solar *** of the properties are also compared with those of the Al-based Ni3 Al compound.

关键词： first principle calculations fermi surface elastic moduli entropy and internal energy optical properties

microstructural characteristics and second-phase particles in yttrium-bearing fe-10Ni-7mn martensitic steels

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Journal of Rare Earths 2014年第4期32卷 326-333页

作者： f.forghani m.Nili-Ahmadabadi School of metallurgy and materials Engineering College of EngineeringUniversity of Tehran Center of Excellence for High Performance materials University of Tehran

In this study, the microstructure and second-phase particles in yttrium （0.05 wt.%and 0.8 wt.%） bearing fe-10Ni-7mn steels were characterized. The results of X-ray analysis as well as scanning electron microscopy coupled with energy dispersive X-ray spectroscopy indicated the formation of （fe, Ni, mn）17Y2 precipitates with hexagonal structure in a fe-10Ni-7mn-0.8Y （wt.%） alloy. Lattice parameters of these precipitates were calculated as follows：a=0.8485 nm and c=0.8274 nm. formation of Y2O3 sub-micron particles was also confirmed in both yttrium bearing steels via electrolytic phase extraction method. The effect of these precipitates on the prior austenite grain size was investigated. The results revealed that these precipitates had an effective role in controlling the prior austenite grain size.

关键词： fe-10Ni-7mn (wt.%) steel yttrium addition microstructure characterization second-phase particles grain growth rare earths

Cognition and the brain of brood parasitic cowbirds

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Integrative Zoology 2019年第2期14卷 145-157页

作者： David f.SHERRY mélanie f.GUIGUENO Department of Psychology Western University LondonOntario Department of Natural Resource Sciences McGill UniversityMontrealQuebecCanada

Cowbirds are brood *** lay their eggs in the nests of other species,which then incubate the cowbird eggs and raise the young *** and returning to heterospecific nests presents cowbirds with several cognitive *** some species,such as brown-headed cowbirds(molothrus ater),females but not males search for and remember the locations of potential host *** describe recent research on sex differences in cognition and the hippocampus associated with this sex difference in search for host *** brown-headed cowbirds perform better than males on some,but not all,tests of spatial memory and females show a pattern of adult hippocampal neurogenesis not found in males or in closely related non-parasitic *** of the apparent specialization of the hippocampus,brown-headed cowbirds may be a good model in which to examine spatial information processing in the avian hippocampus and we also describe recent research on the spatial response properties of brown-headed cowbird hippocampal neurons.

关键词： adult neurogenesis brood parasites cowbirds hippocampus sex differences spatial memory

A new image watermarking framework based on levels-directions decomposition in contourlet representation

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Journal of Central South University 2017年第3期24卷 521-532页

作者： m.f.Kazemi m.A.Pourmina A.H.mazinan Department of Electrical and Computer Engineering Science and Research BranchIslamic Azad University(IAU)TehranIran Department of Control Engineering Faculty of Electrical EngineeringSouth Tehran BranchIslamic Azad University(IAU)TehranIran

With the development of digital information technologies,robust watermarking framework is taken into real consideration as a challenging issue in the area of image processing,due to the large applicabilities and its utilities in a number of academic and real *** are a wide range of solutions to provide image watermarking frameworks,while each one of them is attempted to address an efficient and applicable *** reality,the traditional techniques do not have sufficient merit to realize an accurate *** to the fact that the main idea behind the approach is organized based on contourlet representation,the only state-of-the-art materials that are investigated along with an integration of the aforementioned contourlet representation in line with watermarking framework are concentrated to be able to propose the novel and skilled *** a word,the main process of the proposed robust watermarking framework is organized to deal with both new embedding and de-embedding processes in the area of contourlet transform to generate watermarked image and the corresponding extracted logo image with high *** fact,the motivation of the approach is that the suggested complexity can be of novelty,which consists of the contourlet representation,the embedding and the corresponding de-embedding modules and the performance monitoring including an analysis of the watermarked image as well as the extracted logo *** is also a scrambling module that is working in association with levels-directions decomposition in contourlet embedding mechanism,while a decision maker system is designed to deal with the appropriate number of sub-bands to be embedded in the presence of a series of simulated *** required performance is tangibly considered through an integration of the peak signal-to-noise ratio and the structural similarity indices that are related to watermarked *** the bit error rate and the normal correlation are considered that are

关键词： contourlet based watermarking framework levels-directions decomposition embedding process de-embedding process peak signal-to-noise ratio structural similarity indices normal correlation bit error rate

Level-direction decomposition analysis with a focus on image watermarking framework

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frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1199-1217页

作者： m.f.KAZEmI m.A.POURmINA A.H.mAZINAN Department of Electrical and Computer Engineering Science and Research Branch Islamic Azad University Department of Control Engineering Faculty of Electrical Engineering South Tehran Branch Islamic Azad University

This research addresses the new level-direction decomposition in the area of image watermarking as the further development of investigations. The main process of realizing a watermarking framework is to generate a watermarked image with a focus on contourlet embedding representation. The approach performance is evaluated through several indices including the peak signal-to-noise ratio and structural similarity, whereby a set of attacks are carried out using a module of simulated attacks. The obtained information is analyzed through a set of images, using different color models, to enable the calculation of normal correlation. The module of the inverse of contourlet embedding representation is correspondingly employed to obtain the present watermarked image, as long as a number of original images are applied to a scrambling module, to represent the information in disorder. This allows us to evaluate the performance of the proposed approach by analyzing a complicated system, where a decision making system is designed to find the best level and the corresponding direction regarding contourlet embedding representation. The results are illustrated in appropriate level-direction decomposition. The key contribution lies in using a new integration of a set of subsystems, employed based upon the novel mechanism in contourlet embedding representation, in association with the decision making system. The presented approach is efficient compared with state-of-the-art approaches, under a number of serious attacks. A number of benchmarks are obtained and considered along with the proposed framework outcomes. The results support our ideas.

关键词： Level-direction decomposition analysis Watermarking framework Contourlet embedding representation Scrambling module Simulated attacks

Electrical Conductivity and Sensitive Characteristics of Ag-Added BaTiO_3-CuO mixed Oxide for CO_2 Gas Sensing

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Journal of materials Science & Technology 2011年第1期27卷 35-40页

作者： A.m.El-Sayed f.m.Ismail S.m.Yakout Inorganic Chemistry Department National Research CentreTahrir StreetDokki P.C.12622 CairoEgypt

Carbon dioxide gas sensors based on BaTiO3-CuO composite with different concentrations of Ag addition（1,1.5 and 2 wt%） have been prepared by stander ceramic method and sintered at 500 and 700℃ for 5 *** conductivity and gas sensing properties of the prepared samples were *** conductivity measurement was used to characterize the obtained sintered sensor *** was found that electrical conductivity and the sensitivity to CO2 were improved with Ag addition and *** correlation between Ag content at different sintering temperature and sensing characteristics towards CO2 is discussed.

关键词： BaTiO3-CuO composite Ag addition Electrical conductivity CO2 sensitive properties

Analysis of interlaminar stress and nonlinear dynamic response for composite laminated plates with interfacial damage

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Acta mechanica Sinica 2008年第6期24卷 709-720页

作者： f.H.Zhu .m.fu College of mechanics and Aerospace Hunan University410082 ChangshaChina

By considering the effect of interfacial damage and using the variation principle, three-dimensional nonlinear dynamic governing equations of the laminated plates with interfacial damage are derived based on the general sixdegrees-of-freedom plate theory towards the accurate stress analysis. The solutions of interlaminar stress and nonlinear dynamic response for a simply supported laminated plate with interfacial damage are obtained by using the finite difference method, and the results are validated by comparison with the solution of nonlinear finite element method. In numerical calculations, the effects of interfacial damage on the stress in the interface and the nonlinear dynamic response of laminated plates are discussed.

关键词： Laminated plates Geometric nonlinearity Accurate stress analysis Interfacial damage Interlaminar stress Nonlinear dynamic response

Analytical study of Cattaneo–Christov heat flux model for a boundary layer flow of Oldroyd-B fluid

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Chinese Physics B 2016年第1期25卷 657-662页

作者： f m Abbasi m mustafa S A Shehzad m S Alhuthali T Hayat Department of mathematics Comsats Institute of lnformaHon TechnologyIslamabad 44000Pakistan School of Natural Sciences(SNS) National University of Science and Technology(NUST)Islamabad 44000Pakistan Department of mathematics Comsats Institute of/nformation TechnologySahiwa157000Pakistan NAAm Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of mathematics Quaid-I-Azam University 45320Islamabad 44000Pakistan

We investigate the Cattaneo-Christov heat flux model for a two-dimensional laminar boundary layer flow of an incompressible Oldroyd-B fluid over a linearly stretching sheet. mathematical formulation of the boundary layer problems is given. The nonlinear partial differential equations are converted into the ordinary differential equations using similarity transformatioris. The dimensionless velocity and temperature profiles are obtained through optimal homotopy analysis method （OHAm）. The influences of the physical parameters on the velocity and the temperature are pointed out. The results show that the temperature and the thermal boundary layer thickness are smaller in the Cattaneo-Christov heat flux model than those in the fourier＇s law of heat conduction.

关键词： Oldroyd-B fluid Cattaneo-Christov heat flux nonlinear analysis

Pullulan production by Aureobasidium pullulans mTCC 1991 from apple pomace and its characterization

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food Bioscience 2023年第1期51卷 1380-1387页

作者： Shoib mohmad wani f.A.masoodi Sajad Ahmad mir f.A.Khanday Department of Biotechnology University of KashmirHazratbal SrinagarJ&K190006India Department of food Science&Technology University of KashmirHazratbal SrinagarJ&K190006India

Apple pomace,a by-product of the apple juice processing industry,is significant agro-based waste in the Union Territory of Jammu&Kashmir,India.A considerable amount of apple is processed for juice production,resulting in a surplus of apple pomace,which is generally *** study utilized apple pomace as a substrate matrix for producing pullulan by applying Aureobasidium pullulans mTCC ***-state fermentation was done at a lab scale in Erlenmeyer flasks to produce this *** suitable conditions for solid-state fermentation of apple pomace were:a solid-liquid ratio of 1:4,inoculum volume of 3 mL,pH 6 and incubation time of 14 days.A yield of 42 mg/g dw was obtained in the control sample without adding any other nutrients or *** addition of yeast extract at a concentration of 1%(w/w)and sucrose(5%w/w)significantly(pmg/g dw and 75 mg/g dw,*** purified pullulan had similar characteristics to that of standard pullulan,as confirmed by ATR-fTIR,H NmR and TLC *** production from apple pomace can be a better way to utilize this by-product from the apple juice *** will be a cost-effective technique for pullulan production as an inexpensive substrate and an environmentally friendly approach are also used.

关键词： Biopolymer microbial polysaccharide Agro-based waste Solid state fermentation Waste utilization

The use cases of digital earth

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International Journal of Digital Earth 2008年第1期1卷 31-42,I0003页

作者： m.f.Goodchild National Center for Geographic Information and Analysis and Department of GeographyUniversity of CaliforniaSanta BarbaraCA 93106-4060USA

The formal process of system design begins with the identification of use *** such cases are readily apparent for the current generation of geobrowsers,though the text of the 1998 Gore speech refers to *** analysis of the use cases of geographic information systems(GIS)reveals similarities with the functionality of geobrowsers,inviting the view that the two forms of geographic information technology will eventually ***,experience suggests that users are finding very different ways of exploiting geobrowsers,and two examples are discussed in *** uses can be interpreted within a broad framework of spatial concepts,and the paper concludes that this framework provides a better guide to the future of geobrowsers and Digital Earth than current GIS technology.

关键词： use case geobrowser GIS spatial concept digital earth