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Continuous query scheduler based on operators clustering

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Journal of Central South University 2011年第3期18卷 782-790页

作者： m.Sami Soliman 谭冠政 School of Information Science and Engineering Central South University

Data stream management system (DSmS) provides convenient solutions to the problem of processing continuous queries on data *** approaches for scheduling these queries and their operators assume that each operator runs in separate thread or all operators combine in one query plan and run in a single *** approaches suffer from severe drawbacks concerning the thread overhead and the stalls due to expensive *** overcome these drawbacks,a novel approach called clustered operators scheduling (COS) is proposed that adaptively clusters operators of the query plan into a number of groups based on their selectivity and computing cost using S-mean *** evaluation is provided to demonstrate the potential benefits of COS scheduling over the other scheduling *** can provide adaptive,flexible,reliable,scalable and robust design for continuous query processor.

关键词：集群调度连续查询运营商数据流管理系统查询计划查询处理器 DSmS 群体数量

Nonlinear convection in a non-Darcy porous medium

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Applied mathematics and mechanics(English Edition) 2010年第5期31卷 565-574页

作者： m. K. PARTHA Department of mathematics Malnad College of Engineering

In this paper, the natural convection in a non-Darcy porous medium is studied using a temperature-concentration-dependent density relation. The effect of the two parameters responsible for the nonlinear convection is analyzed for different values of the inertial parameter, dispersion parameters, Rayleigh number, Lewis number, Soret number, and Dufour number. In the aiding buoyancy, the tangential velocity increases steeply with an increase in the nonlinear temperature parameter and the nonlinear concentration parameter when the inertial effect is zero. However, when the inertial effect is non-zero, the effect of the nonlinear temperature parameter and the nonlinear concentration parameter on the tangential velocity is marginal. The concentration distribution varies appreciably and spreads in different ranges for different values of the double dispersion parameters, the inertial effect parameter, and also for the parameters which control the nonlinear temperature and the nonlinear concentration. Heat and mass transfer varies extensively with an increase in the nonlinear temperature parameter and the nonlinear concentration parameter depending on Dacry and non-Darcy porous media. The variation in heat and mass transfer when all the effects, i.e., the inertial effect, double dispersion ef- fects, and Soret and Dufour effects, are simultaneously zero and non-zero. The combined effects of the nonlinear temperature parameter, the nonlinear concentration parameter and buoyancy are analyzed. The effect of the nonlinear temperature parameter and the nonlinear concentration parameter and also the cross diffusion effects on heat and mass transfer are observed to be more in Darcy porous media compared with those in non- Darcy porous media. In the opposing buoyancy, the effect of the temperature parameter is to increase the heat and mass transfer rate, whereas that of the concentration parameter is to decrease.

关键词： non-Darcy porous medium natural convection double dispersion

扩散加权全身mRI与PET/CT在转移高风险乳腺癌病人初始分期中的评估对比：一项前瞻性队列研究

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国际医学放射学杂志 2024年第2期 248-248页

作者： N.A.Hottat D.A.Badr m.Ben Ghanem T.Besse-Hammer S.m.Lecomte C.Vansteelandt 李晓舒

摘要目的比较扩散加权全身mRI(WB-mRI)与PET/CT对转移高风险乳腺癌的早期评估。方法前瞻性纳入45名女性。纳入标准：女性、年龄>18岁、浸润性乳腺癌、首次

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magnetic filtration of an iron oxide aerosol by means of magnetizable grates

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China Particuology 2007年第1期5卷 140-144页

作者： A. Alvaro J.m. Rodríguez Paulo A. Augusto A.m. Estvez Department of Chemical Engineering University of Salamanca Plaza de los Caídos 1-5 37008 Salamanca Spain Department of Chemical Engineering University of Salamanca Plaza de los Caídos 1-5 37008 Salamanca Spain Department of Chemical Engineering Faculty of Engineering University of Porto Rua Dr. Roberto Frias 4200-465 Porto Portugal

The cleaning of gases with low concentrations of small ferromagnetic or paramagnetic particles is a difficult task for conventional filtration. A new alternative procedure, magnetic filtration, is used in this work. Iron oxide aerosol was generated by elutriation of iron oxide particles from a fluidized bed consisting of a mixture of Geldart-C iron oxide powder and large spherical Geldart-B sand particles. The aerosol was filtered by means of a magnetic filter which consisted of one, two or three iron grates staggered to each other. The experimental installation contained also an isokinetic sampling system and a microtrac SRA 150 Particle Analyser. A theoretical expression for filtration efficiency was deduced from a previous model taking into account the different forces acting on the iron oxide particles. Experimental filtration efficiency matches quite well calculated theoretical efficiency. It was found that an increase in particle size, in thee number of grates or in the applied magnetic field produced higher filtration efficiencies up to 100% in some cases. In all filtration experiments pressure drop through the magnetic filter was very small.

关键词： Iron oxide aerosol magnetic filtration Iron grates

Effects of f(R) model on Dynamics of Axial Shear-Free Dissipative Fluids

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Communications in Theoretical Physics 2016年第4期65卷 483-491页

作者： m.Sharif Zunaira Nasir Department of mathematics University of the Punjab

We present a general analysis on non-static axial system with dissipative shear-free anisotropic fluid using polynomial inflationary f(R) *** study the effects of dissipation on the dynamics of geodesic matter *** leads the system either to rotation-free or expansion-free but not both simultaneously under geodesic *** is found that the system preserves its symmetry in both *** the rotation-free case,when there is no dissipation and Ricci scalar is constant,the axial system reduces to FRW universe *** is exactly the same result obtained in general relativity.

关键词：流体动力学自由膨胀宇宙模型耗散剪切轴流自由旋转广义相对论

Ocellar lamprophyre dyke bearing mineralization,Wadi Nugrus,Eastern Desert,Egypt:Geology,mineralogy and geochemical implications

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Chinese Journal Of Geochemistry 2010年第4期29卷 383-392页

作者： Ibrahim m.E. Saleh G.m. Dawood N.A. Aly G.m. Nuclear materials Authority P.O.Box 530El-MaadiCairoEgypt

The ocellar lamprophyre dyke(ENE-WSW) is recorded at Wadi Nugrus,Eastern Desert,*** cuts porphyritic biotite granites and varies in thickness from 0.5 to 1.5 m and up to 3 km in *** lamprophyre dyke has been altered,and it is characterized by porphyritic and panidiomorphic textures with plagioclase,olivine,and augite constituting the porphyritic phase in a fine groundmass of the same ***,titanite,apatite,fluorite,graphite,calcite,allanite,autunite and Fe-Ti oxides are accessory ***,chlorite and epidote are secondary *** and hematitization are *** to sub-rounded porphyritic and zoned ocelli with radiate or brush-like shapes are generally common and represent physical traps for *** ocellar features are interpreted to represent the late stage of magmatic segregation or magmatic crystallization involving two immiscible magmatic *** studies of altered lamprophyre samples,based on X-ray diffraction(XRD) and environmental scanning electron microscopy(ESEm),indicate the presence of secondary uranium minerals(autunite and uranophane),associated with gold,silver,nickel,atacamite,molybdenum,pyrite and *** presence of kaolinite indicates a high temperature *** mixing of volatile fluids with meteoric water and fluid-wall rock interaction result in changes of pH and oxygen activity and deposition of base metals in reducing environs(graphite and pyrite).Precipitation of hematite probably decreased the pH of the solution and rose acidic *** sudden change in pH and temperature of the fluids would lead to destabilization of base metal complexes favoring their *** magma source of the Nugrus lamprophyre is determined to be between calc-alkaline and alkaline and it has HKCAB and shoshonitic nature and may be derived from decomposition melting of such a metasomatised lithospheric *** is a major fractional phase to account for a rapid

关键词：煌斑岩脉矿物学地球化学沙漠埃及地质学黑云母花岗岩矿化

Effect of Zinc additive on dielectric properties of Cd–Se glassy system

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Progress in Natural Science:materials International 2015年第3期25卷 222-228页

作者： mohsin Ganaie m.Zulfequar Department of Physics Jamia Millia Islamia

Cd5Se95–xZnx(x=0, 2, 4, 6) glassy alloy has been prepared by a melt-quenching technique. Thin films were deposited by thermal coating unit on ultraclean glass substrate under a vacuum of 10–6Torr. The absence of any sharp peaks in the X-ray diffraction confirms the amorphous nature of thin films. The frequency and temperature dependence of dielectric constant and dielectric loss in the frequency range of 1 kHz to 1 mHz and in the temperature range of 290–370 K were studied. Dielectric dispersion was observed when Zinc(Zn) was incorporated into the Cd–Se *** increase in dielectric parameter with Zn concentration may be due to increase in defect states. The DC conductivity has been reported to investigate the effect of Zn concentration on DC conduction loss. The results are interpreted in term of dipolar theory for Cd5Se95 and Cd5Se93Zn2samples, while the remaining samples have been explained on the basis of DC conduction loss. It was also observed that the DC conductivity increased with the increase of Zinc concentration, which may be due to the decrease in the band gap near Fermi level.

关键词： Amorphous semiconductor Localized states DC conductivity Dielectric constant Dielectric loss

Nurses’ and midwives’ participation and utilization of health-related research in Kenya: Implications for evidence-based practice

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International Journal of Nursing Sciences 2023年第2期10卷 199-205页

作者： Daniel m.Nzengya Albanus K.mutisya miriam C.A.Wagoro molly Secor-Turner Joan Edwards Research and Innovation St.Paul’s UniversityLimuruKenya School of Nursing Jomo Kenyatta University of Agriculture&TechnologyNairobiKenya Department of Nursing Sciences University of NairobiNairobiKenya mark and Robyn Jones College of Nursing Montana State UniversityBozemanMTUSA Nelda C.Stark College of Nursing Texas Woman's UniversityHoustonTXUSA

Objective To assess the level of participation of nurses and midwives in health-related research,determine the status of utilization of research to inform nursing and midwifery practice in Kenya,and explore perspectives of nurses and midwives about strategies to empower nurses/midwives to engage in health research in *** Data were extracted from online survey responses of 156 nurse and midwife educators,practitioners,and managers/*** version 26 was used to analyze quantitative data;qualitative data were analyzed using Excel to organize data into *** Over one-third of participants reported ever publishing research(37.2%,58/156).Participants reported using knowledge gained in nursing school to guide practice most frequently(n=148).Utilization of research findings to guide practice was reported by 80.3%(110/137)of *** to enhance participation in the research included research training,research forums,policy reforms,and emphasis on research in *** There is need to intensify and prioritize proposed strategies to empower nurses/midwives to engage in health research.

关键词： Evidence-based practice Kenya midwifery Nurses Research

Cannabinoids function in defense against chewing herbivores in Cannabis sativa L.

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Horticulture Research 2023年第11期10卷 131-140页

作者： George m.Stack Stephen I.Snyder Jacob A.Toth michael A.Quade Jamie L.Crawford John K.mcKay John Nicholas Jackowetz Ping Wang Glenn Philippe Julie L.Hansen Virginia m.moore Jocelyn K.C.Rose Lawrence B.Smart Horticulture Section School of Integrative Plant ScienceCornell UniversityCornell AgriTechGenevaNY 14456United States Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853United States Plant Breeding Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853United States Department of Agricultural Biology Colorado State UniversityFort CollinsCO 80523United States Cirona Labs GenevaNY 14456United States Department of Entomology Cornell UniversityCornell AgriTechGenevaNY 14456United States

In the decades since the first cannabinoids were identified by scientists,research has focused almost exclusively on the function and capacity of cannabinoids asmedicines and intoxicants for humans and other *** little is knownabout the adaptive value of cannabinoid production,though several hypotheses have been proposed including protection from ultraviolet radiation,pathogens,and *** test the prediction that genotypeswith greater concentrations of cannabinoidswill have reduced herbivory,a segregating F2 population of Cannabis sativa was leveraged to conduct lab-and field-based bioassays investigating the function of cannabinoids in mediating interactions with chewing *** the field,foliar cannabinoid concentration was inversely correlated with chewing herbivore *** detached leaves,Trichoplusia ni larvae consumed less leaf area and grew less when feeding on leaves with greater concentrations of *** electron and light microscopy were used to characterize variation in glandular trichome ***-free genotypes had trichomes that appeared *** isolate cannabinoids from confounding factors,artificial insect diet was amended with cannabinoids in a range of physiologically relevant *** grew less and had lower rates of survival as cannabinoid concentration *** results support the hypothesis that cannabinoids function in defense against chewing herbivores.

关键词： function founding ultraviolet