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STUDY ON NANOmETER ZINc PARTIcLES FABRIcATED BY GAS EVAPORATION mETHOD

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Acta metallurgica Sinica(English Letters) 2003年第3期16卷 161-168页

作者： A.A.A.Saleh X.J.Zhai Y.c.Zhai Y.Fu A.L.Zhang School of materials and metallurgy Northeastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004China

Nanometer Zn particles with mean diameters 12-100nm made by evaporating its powders in argon gas were studied mainly by X-ray diffraction and electron microscopy. They are collected at various distances and those factors influencing the mean particle size were studied. The optimal synthetic conditions were obtained, i.e., evaporation temperature is 1200℃; argon flow rate is 0.4m3/h; amount of powder charged is 3g; distance from evaporation source is 10cm. It was found that the size of particles was governed by argon flow rate, evaporation temperature, amount of metal charged and distance from the source. The size increases remarkably with distance in the space where no metal vapor exists. This implies that the crystallites grow by coalescence. Electron micrographs and diffraction patterns are reproduced to show the size, shape and state of oxidations. Nanoparticles with definite crystal habits were sometimes observed among those with irregular ones.

关键词： gas evaporation method nanometer Zn XRD TEm

manufacturing of Long Products made of Innovative Lightweight materials

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Acta metallurgica Sinica(English Letters) 2015年第12期28卷 1496-1502页

作者： Karsten Richter Roland müller Andreas Kunke Verena Kr? usel Dirk Landgrebe Fraunhofer Institute for machine Tools and Forming Technology (IWU) Professorship Forming and Joining (UFF) Technische Universit?t Chemnitz

The processing of innovative lightweight materials to sheet metal components and assemblies with globally or locally defined properties is the object of this work. It takes a load-dependent design of components and assemblies, for example, based on the composition of different construction materials or a targeted setting of component areas with specified characteristics to fully exploit the lightweight potential when substituting conventionally used materials. Different process chains for the manufacturing of roll-formed long products made of magnesium alloys and high-strength steels with locally defined properties will be presented in this paper. Depending on the kind of material to be formed and the desired product characteristics, different temperature managements are needed for capable processes. Due to limited formability at room temperature, magnesium alloys require a heating of the forming zones above 200–225 °c throughout the bending process in order to activate additional gliding planes and to avoid any failures in the radii. The realization of local hardening effects requires at least one process-integrated heat treatment when roll forming manganese–boron steels. For both processes, it is imperative to realize a heating and cooling down or quenching appropriate for the manufacturing of long products with the required quality. Additionally, proper line speeds that allow a continuously operated economical production have to be considered. Research results including design, FEA, realization and experimentation of the mentioned process chains and strategies will be described in detail.

关键词： Roll forming Heat treatment Lightweight component Light metals manganese steels AZ31 magnesium alloy

An Efficient Long Short-Term memory model for Digital cross-Language Summarization

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computers, materials & continua 2023年第3期74卷 6389-6409页

作者： Y.c.A.Padmanabha Reddy Shyam Sunder Reddy Kasireddy Nageswara Rao Sirisala Ramu Kuchipudi Purnachand Kollapudi Department of cSE B V Raju Institute of TechnologyNarsapurMedakT.S502313India Department of IT Vasavi College of EngineeringHyderabadT.S500089India Department of cSE K.S.R.M College of EngineeringKadapaA.P516003India Department of IT C.B.I.TGandipetHyderabadTelangana500075India

The rise of social networking enables the development of multilingual Internet-accessible digital documents in several *** digital document needs to be evaluated physically through the cross-Language Text Summarization(cLTS)involved in the disparate and generation of the source ***-language document processing is involved in the generation of documents from disparate language sources toward targeted *** digital documents need to be processed with the contextual semantic data with the decoding *** paper presented a multilingual crosslanguage processing of the documents with the abstractive and summarising of the *** proposed model is represented as the Hidden markov model LSTm Reinforcement Learning(HmmlstmRL).First,the developed model uses the Hidden markov model for the computation of keywords in the cross-language words for the *** the second stage,bi-directional long-short-term memory networks are used for key word extraction in the cross-language ***,the proposed HmmlstmRL uses the voting concept in reinforcement learning for the identification and extraction of the *** performance of the proposed HmmlstmRL is 2%better than that of the conventional bi-direction LSTm model.

关键词： Text summarization reinforcement learning hidden markov model cross-language multilingual

Performance study of selective encryption in comparison to full encryption for still visual images

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Journal of Zhejiang University-Science c(computers and Electronics) 2014年第6期15卷 435-444页

作者： Osama A.KHASHAN Abdullah m.ZIN Elankovan A.SUNDARARAJAN centre for Software Technology and management Faculty of Information Science and TechnologyNational University of Malaysia (UKM)

Securing digital images is becoming an important concern in today's information security due to the extensive use of secure images that are either transmitted over a network or stored on disks. Image encryption is the most effective way to fulfil confidentiality and protect the privacy of images. Nevertheless, owing to the large size and complex structure of digital images, the computational overhead and processing time needed to carry out full image encryption prove to be limiting factors that inhibit it of being used more heavily in real time. To solve this problem, many recent studies use the selective encryption approach to encrypt significant parts of images with a hope to reduce the encryption overhead. However, it is necessary to realistically evaluate its performance compared to full encryption. In this paper, we study the performance and efficiency of image segmentation methods used in the selective encryption approach, such as edges and face detection methods, in determining the most important parts of visual images. Experiments were performed to analyse the computational results obtained by selective image encryption compared to full image encryption using symmetric encryption algorithms. Experiment results have proven that the selective encryption approach based on edge and face detection can significantly reduce the time of encrypting still visual images as compared to full encryption. Thus, this approach can be considered a good alternative in the implementation of real-time applications that require adequate security levels.

关键词： Selective image encryption Edge detection Face detection

利用超快速动态增强乳腺mRI衍生的血流动力学参数鉴别亚厘米癌与良性病变

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国际医学放射学杂志 2020年第2期 248-249页

作者： N.Onishi m.Sadinski P.Gibbs K.m.Gallagher m.c.Hughes E.S.Ko 班然然 Breast Imaging Service Department of RadiologyMemorial Sloan Kettering Cancer Center

目的旨在评估超快速动态增强(DcE)-mRI衍生技术反映对比剂流入效应的血流动力学参数区分亚厘米BI-RADS4-5级乳腺癌和良性病变能力。方法回顾性分析

关键词： mRI DcE 动态增强力学参数

STABILITY OF GENERALIZED DERIVATIONS ON HILBERT c*-mODULES ASSOcIATED WITH A PEXIDERIZED cAUcHY-JENSEN TYPE FUNcTIONAL EQUATION

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Acta mathematica Scientia 2012年第3期32卷 1226-1238页

作者： Ali Ebadian Ismail Nikoufar Themistocles m.Rassias Norouz Ghobadipour Department of mathematics Payame Noor UniversityPO Box 19395-3697 TehranIran Department of mathematics National Technical University of AthensZografouCampus 15780 AthensGreece Department of mathematics Urmia UniversityUrmiaIran

In this article, we introduce the notion of generalized derivations on Hilbert c＊-modules. We use a fixed-point method to prove the generalized Hyers-Ulam-Rassias stability associated to the Pexiderized cauchy-Jensen type functional equationrf（x＋y/r）＋sg（x-y/s）=2h（x）for r, s ∈ R ／ c on Hilbert c＊-modules, where f, g, and h are mappings from a Hilbert c＊-module m to m.

关键词： Hyers-Ulam-Rassias stability Hilbert c*-module generalized derivation fixed point

Spatio-Temporal Effect on Soil Respiration in Fine-Scale Patches in a Desert Ecosystem

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Pedosphere 2006年第1期16卷 1-9页

作者： S. PEN-mOURATOV m. RAKHImBAEV Y. STEINBERGER Faculty of Life Sciences Bar-Ilan University Ramat-Gan 52900 (Israel) Faculty of Life Sciences Bar-Ilan University Ramat-Gan 52900 (Israel) Institute of Botany Tashkent (Uzbekistan)

Soil organisms in terrestrial systems are unevenly distributed in time and space, and often aggregated. Spatiotemporal patchiness in the soil environment is thought to be crucial for the maintenance of soil biodiversity, providing diverse microhabitats tightly interweaving with resource partitioning. Determination of a ＂scale unit＂ to help understand ecological processes has become one of the important and most debatable problems in recent years. A fieldwork was carried out in the northern Negev Desert highland, Israel to determine the influence of fine-scale landscape patch moisture heterogeneity on biogeochemical variables and microbial activity linkage in a desert ecosystem. The results showed that the spatio-temporal patchiness of soil moisture to which we attribute influential properties, was found to become more heterogenic with the decrease in soil moisture availability （from 8.2 to 0.4 g kg^-1） toward the hot, dry seasons, with coefficient of variation （cV） change amounting to 66.9%. Spatio-temporal distribution of organic matter （Om） and total soluble nitrogen （TSN） was found to be relatively uniformly distributed throughout the wet seasons （winter and spring）, with increase of relatively high heterogeneity toward the dry seasons （from 0.25% to 2.17% for Om, and from 0 to 10.2 mg kg^-1 for TSN） with cV of 47.4% and 99.7% for Om and TSN, respectively. Different spatio-temporal landscape patterns were obtained for ca （cV = 44.6%）, K （cV = 34.4%）, and Na （cV = 92%） ions throughout the study period. cO2 evolution （cV = 48.6%） was found to be of lower heterogeneity （varying between 2 and 39 g cO2-c g^-1 dry soil h^-1） in the moist seasons, e.g., winter and spring, with lower values of respiration coupled with high heterogeneity of Na^＋ and low levels of TSN and organic matter content, and with more homogeneity in the dry seasons （varying between 1 and 50 g cO2-c g^-1 dry soil h^-1）. Our results elucidate the heterogeneity and complexity of desert system habitats

关键词： desert microbial respiration patchiness small-scale habitat soil

Stimulated Raman Scattering in a Weakly Polar Ⅲ-Ⅴ Semiconductor： Effect of dc magnetic Field and Free carrier concentration

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chinese Physics Letters 2007年第8期24卷 2245-2248页

作者： m. Singh P. Aghamkar P. K. Sen Department of Applied Physics Guru Jambheshwar University of Science and Technology Hisar-125001 India Department of Applied Physics S.G.S. Institute of Technology and Science 23-Park Road Indore-452003 India

Using the hydrodynamic model of semiconductor plasmas, we perform an analytical investigation of stimulated Raman scattering （SITS） of an electromagnetic pump wave in a transversely magnetized weakly polar semicon- ductor arising from electron-density perturbations and molecular vibrations of the medium both produced at the longitudinal optical phonon frequency. Assuming that the origin of SItS lies in the third-order susceptibility of the medium, we investigate the growth rate of Stokes mode. The dependence of stimulated Raman gain on the external dc magnetic field strength and free carrier concentration is reported. The possibility of the occurrence of optical phase conjugation via SItS is also studied. The steady-state Raman gain is found to be greatly enhanced by the presence of the strong external dc magnetic field.

关键词： Stimulated Raman Scattering Weakly Polar Semiconductor

Oil-bearing fluid inclusions from the Palaeoproterozoic:A review of biogeochemical results from time-capsules >2.0 Ga old

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Science china Earth Sciences 2009年第1期52卷 1-11页

作者： Simon c. GEORGE Adriana DUTKIEWIcZ Herbert VOLK John RIDLEY David J. mOSSmAN Roger BUIcK Department of Earth and Planetary Sciences Macquarie University School of Geosciences University of Sydney cSIRO Petroleum Department of Geosciences Colorado State University Department of Geography Mount Allison University Department of Earth and Space Sciences & Astrobiology Program University of Washington

The observation of oil inclusions trapped prior to 2.0 Ga in Palaeoproterozoic rocks and the ability to obtain detailed molecular geochemical information from them provide a robust way for understanding the early biog... 详细信息

关键词： Palaeoproterozoic fluid inclusion oil biomarker blank