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Analysis of Solidification in Spray Atomized and Codeposited metal-matrix Composites Part Ⅰ: Atomization

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Journal of materials Science & Technology 1995年第3期11卷 79-90页

作者： V.Erukhimovitch and J.Baram(materials Engineering Department, Ben-Gurion University of Negev, Beer-Sheva, israel) Ben-Gurion Univ of Negev Beersheva Israel

Fluid mechanics, heat transfer and liquid-to-solid phase transformation are assessed in optimizing the spray atomization and codeposition process parameters for size refinement and microstructural uniformity of the deposited material. Atomization gas velocities, atomized droplets velocities, convective heat transfer coefficients, thermal histories of the solidifying droplets, freezing rates, fraction solid evolution and solid-liquid interface propagation velocity are calculated. The influence, on the deposit microstructural features, of process parameters like the atomization gas pressure, the pouring tube orifice diameter, the geometrical features of the atomization device,the potency of , pre-existing or injected as reinforcement, nucleation sites, the wetting angle between the liquid melt bnd impurity particles acting as preferred nucleation sites, the in-flight distance of the solidifying droplets in the atomization chamber, i5 evaluated. As a result of the evaluation, appropriate choice of the adjustable process parameters for the production of powders and/or deposits with desired grain size and microstructure, can be made.

关键词： Co Figure Atomization Analysis of Solidification in Spray Atomized and Codeposited metal-matrix Composites Part

Strategic Human Resource management: Enhancing and Prolonging Organization's Competitive Edge

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Strategic Human Resource Management: Enhancing and Prolongin...

作者： israel CHOKO DAVIes（伊大伟）南昌大学

学位级别：硕士

most organizations down place a high focus on human capital management as a major component of competitive advantage. A primary reason for such is that these institutions still adopt the conventional HRm, the formal practices for managing people in organization, which essentially concerned itself with transactional and administrative support services;such as, hiring, firing, staffing, etc. In contemporary realistic world, such traditional HRm practices are quite insufficient to provide a competitive edge to institutions. In order for an organization to be successful in any market, it must create value for their clients. making use of a new strategy, new technology or some other gimmick;this value can be created. However, to sustain this value and the competitive advantage it brings, organizations must develop and maintain an engaged, knowledgeable and creative workforce (Afiouni,2007). Additionally, globalization of companies and capital markets has changed the business landscape. The continuing removal of trade barriers and tariffs, the consequent globalization of markets, the volatility of consumer demands within existing markets, currency fluctuations, and political upheaval are by now familiar characteristics of an environment in flux. The capability of people to cope and manage within such an environment is a vital element in the success of any business and can not be over emphasized. To adequately respond in order to remain competitive, companies must manage their assets as effectively as possible—with specific reference to their human assets. It is against these backgrounds this report is provided, which considers a variety of models to adapt one's overall HR strategy to the new realities of global competition and to also emphasize the need for managements to take a greater interest in the utilization of their organizations' human resources in a bid to achieve competitive advantage.

关键词： Human resource management strategic human resource management competitive edge fit integration resource base view business strategy strategic business metrics

mathematical modeling of the impact of temperature variations and immigration on malaria prevalence in Nigeria

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International Journal of Biomathematics 2021年第8期14卷 215-252页

作者： Eunice E.Ukwajunor Eno E.E.Akarawak israel Olutunji Abiala Department of mathematics University of LagosLagos StateNigeria

The study examines the population-level impact of temperature variability and immigration on malaria prevalence in Nigeria,using a novel deterministic *** model incorporates disease transmission by immigrants into the *** the absence of immigration,the model is shown to exhibit the phenomenon of backward *** disease-free equilibrium of the autonomous version of the model was found to be locally asymptotically stable in the absence of infective ***,the model exhibits an endemic equilibrium point when the immigration parameter is greater than *** endemic equilibrium point is seen to be globally asymptotically stable in the absence of disease-induced *** and sensitivity analysis of the model,using parameter values and ranges relevant to malaria transmission dynamics in Nigeria,shows that the top three parameters that drive malaria prevalence(with respect to R_(0))are the mosquito natural death rate(μm),mosquito biting rate(bm)and the transmission rates between humans and mosquitoes(βH,βm).Numerical simulations of the model show that in Nigeria,malaria burden increases with increasing mean monthly temperature in the range of 22–28℃.Thus,this study suggests that control strategies for malaria should be intensified during this *** is further shown that the proportion of infective immigrants has marginal effect on the transmission dynamics of the ***,the simulations suggest that a reduction in the fraction of infective immigrants,either exposed or infectious,would significantly reduce the malaria incidence in a population.

关键词： malaria immigration basic reproduction number temperature variability stability

Prognostic performance of an index based on lactic dehydrogenase and transaminases for patients with liver steatosis and COVID-19

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World Journal of Gastroenterology 2022年第37期28卷 5444-5456页

作者： Ricardo Ulises macías-Rodríguez Alberto Adrián Solís-Ortega Victoria J Ornelas-Arroyo Astrid Ruiz-margáin maria Sarai González-Huezo Nestor A Urdiales-morán Berenice m Román-Calleja Juan m mayorquín-Aguilar JoséA González-Regueiro Alejandro Campos-murguía israel Vicente Toledo-Coronado mónica Chapa-Ibargüengoitia Bernardo Valencia-Peña Carlos Fernando martínez-Cabrera Nayelli C Flores-García Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Department of Gastroenterology Centro Médico ISSEMYMToluca 52140Mexico Department of Radiology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

BACKGROUND metabolic associated fatty liver disease(mAFLD)is associated with complications and mortality in patients with coronavirus disease 2019(COVID-19).However,there are no prognostic scores aimed to evaluate the risk of severe disease specifically in patients with mAFLD,despite its high *** dehydrogenase,aspartate aminotransferase and alanine aminotransferase have been used as markers of liver ***,we propose an index based on lactate dehydrogenase,aspartate aminotransferase and alanine aminotransferase for the prediction of complications and mortality in patients with mAFLD and *** To evaluate the prognostic performance of an index based on lactate dehydrogenase and transaminases(aspartate aminotransferase/alanine aminotransferase)in patients with COVID-19 and mAFLD[liver fibrosis and nutrition(LNF)-COVID-19 index].mETHODS In this retrospective cohort study,two cohorts from two different tertiary centers were *** first was the derivation cohort to obtain the score cutoffs,and the second was the validation *** included hospitalized patients with severe COVID-19 and *** steatosis was evaluated by computed tomography *** under the receiver operating characteristic(ROC)curve analysis and survival analysis were *** In the derivation cohort,44.6%had mAFLD;ROC curve analysis yielded a LFN-COVID-19 index>1.67 as the best cutoff,with a sensitivity of 78%,specificity of 63%,negative predictive value of 91%and an area under the ROC curve of *** the multivariate analysis,the LFN-COVID-19 index>1.67 was independently associated with the development of acute kidney injury(odds ratio:1.8,95%confidence interval:1.3-2.5,Pmance to predict prognosis in patients with mAFLD and COVID-19,which

关键词： COVID-19 metabolic associated fatty liver disease Lactate dehydrogenase Transaminases Prognosis Nonalcoholic fatty liver disease

Assessment of geodetic strain and stress variations in Nepal due to 25 April 2015 Gorkha earthquake:Insights from the GNSS data analysis and b-value

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Geodesy and Geodynamics 2022年第3期13卷 288-300页

作者： Sravanthi Gunti Priyom Roy J.Narendran Ramesh Pudi S.muralikrishnan K.Vinod Kumar m.Subrahmanyam Y.israel B.Satish Kumar National Remote Sensing Centre Indian Space Research Organization(ISRO)BalanagarHyderabad500037India Sustainability Risk Management Solutions of IndiaNoida201301India Department of Geophysics Andhra UniversityVisakhapatnam530003India

A magnitude m;7.8 earthquake occurred on 25 April 2015(referred as Gorkha earthquake).We have analyzed the spatial variation of b-value and two-dimensional strain within Nepal Himalaya before and after the Gorkha *** have used continuous Global Navigation Satellite System(GNSS)data from 30 stations in the Nepal region for geodetic strain estimation and earthquake data for b-value *** GNSS data were processed using double differencing technique for the accurate position of each *** precise velocity vectors show a general azimuth of north east for all the stations and have been used to derive two-dimensional *** epicenters of Gorkha(25 April 2015)and Dolakha earthquakes(12 may 2015),we observed high co-seismic horizontal displacements(0.2 m to 2 m).In the Pre-seismic deformation study,maximum strain accumulation(56.40×10;)and low bvalue(0.79-0.89)was observed in and around the Western Nepal region,which may be responsible for the 2015 Gorkha *** potential seismic zones were identified by GIS based integration of geodetic strain and b-value map and superimposition using weighted overlay *** maximum strain and low b-value are now observed in the eastern part of ***,the spatial disposition of elastic energy has changed after the two major earthquakes and continuous seismic hazard assessment is required in the eastern Nepal.

关键词： Himalaya Co-seismic offsets Bernese 5.2 UNAVCO Grid_Strain

Influence of oxidation of automatic transmission fluids (ATFs) and sliding distance on friction coefficients of a wet clutch in the running-in stage

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Friction 2021年第2期9卷 401-414页

作者： Leonardo israel FARFAN-CABRERA Ezequiel Alberto GALLARDO-HERNÁNDEZ manuel VITE-TORRes Jesús Gilberto GODÍNEZ-SALCEDO Tecnologico de monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501Monterrey 64849México Instituto Politécnico Nacional SEPI-Escuela Superior de Ingeniería Mecánica y EléctricaUnidad ZacatencoGrupo de TribologíaCol.LindavistaCiudad de México 07738México Instituto Politécnico Nacional ESIQIEIPNCol.LindavistaCiudad de México 07738México

In this paper,the influence of oxidation of automatic transmission fluids(ATFs)and sliding distance on the friction coefficients of a wet clutch in approached running-in conditions was *** ATFs were oxidized by a laboratory process approaching oxidation occurred in actual *** was evaluated by means of increase in carbonyl compounds and depletion of zinc dialkyldithiophosphates(ZDDPs)***,the changes in kinematic viscosity and viscosity index were ***-ondisk tests were conducted to replicate the actual sliding contact in a wet *** pin specimens were cut from friction material composite plates and the disks were actual steel separators both from an automotive wet *** coefficient, μ,was measured at progressive sliding velocity,ν,to obtain μ–νcurves at 26 and 100°*** μ–νtests were consecutively run using the same pair of specimens and *** cumulative sliding distance for each μ–νtest generated surface flattening using the *** friction coefficients of the wet clutch increased due to the ATFs oxidation meanwhile the dm/dv values decreased in most *** suggests that ATF oxidation can enhance torque capacity of the wet clutch,but it could reduce anti-shudder *** sliding distance improved the slopes in the μ–νresults using fresh ATFs meanwhile it generated a slope decrease by using aged ATFs.

关键词： wet clutch friction oil oxidation automatic transmission fluid(ATF)

Generating optical orbital angular momentum at visible wavelengths using a plasmonic metasurface

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Light(Science & Applications) 2014年第1期3卷 219-222页

作者： Ebrahim Karimi Sebastian A Schulz israel De Leon Hammam Qassim Jeremy Upham Robert W Boyd Department of Physics University of OttawaOttawaOnt.K1N 6N5Canada Institute of Optics University of RochesterRochesterNY 14627USA

Light beams with a helical phase-front possess orbital angular momentum along their direction of propagation in addition to the spin angular momentum that describes their *** recently,it was thought that these two‘rotational’motions of light were largely independent and could not be coupled during light–matter ***,it is now known that interactions with carefully designed complex media can result in spin-to-orbit coupling,where a change of the spin angular momentum will modify the orbital angular momentum and vice *** this work,we propose and demonstrate that the birefringence of plasmonic nanostructures can be wielded to transform circularly polarised light into light carrying orbital angular momentum.A device operating at visible wavelengths is designed from a space-variant array of subwavelength plasmonic *** confirms that circularly polarised light transmitted through the device is imbued with orbital angular momentum of 62"(with conversion efficiency of at least 1%).This technology paves the way towards ultrathin orbital angular momentum generators that could be integrated into applications for spectroscopy,nanoscale sensing and classical or quantum communications using integrated photonic devices.

关键词： light orbital angular momentum light spin angular momentum plasmonic metasurface

Population dynamics of three lizard species from the genus Sceloporus:short-term changes in demographic parameters

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Integrative Zoology 2019年第6期14卷 542-560页

作者： Selene VARGAS-GARCÍA Víctor ARGAEZ israel SOLANO-ZAVALETA J.Jaime ZÚÑIGA-VEGA Graduate Program in Biological Sciences National Autonomous University of MexicoUniversity CityMexico CityMéxico Department of Ecology and Natural Resources Faculty of SciencesNational Autonomous University of MexicoUniversity CityMexico CityMéxico.

most demographic studies focus on numerical changes that occur within populations across ***,typically studies at an interannual scale do not provide information on the particular times of the year(particular months or seasons)when rates of survival,recruitment,or migration increase or decrease due to physiological,behavioral or ecological *** monthly or seasonal changes in demographic parameters may lead to substantial variations in population *** this study,we collected capture-mark-recapture data on 3 species of lizards of the genus Sceloporus(Sceloporus torquatus,Sceloporus grammicus and Sceloporus megalepidurus)found in ecologically similar habitats to examine potential changes in demographic rates among 3 different climatic seasons:rainy,cold-dry and warm-dry *** tested different hypotheses about the effect of these seasons on survival,recruitment of new adults,and temporary *** found that during the season with severe thermal constraints,the cold-dry season,survival of *** decreased *** also detected a considerable increase in the recruitment rate of *** during the rainy season,when these lizards are establishing territories and finding *** contrast,we found no evidence of intra-annual changes in the rate of temporary *** addition,we calculated abundance and population growth rates for each species and for each *** study represents a significant contribution to the understanding of intra-annual demographic variation in lizards.

关键词： abundance recruitment Sceloporus lizards survival temporary emigration

Economically Optimal Rates and Nutrients Use Efficiency Indices of maize to the Application of Different Rates of Nutrients in Central Rift Valley of Ethiopia

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Agricultural Sciences 2022年第7期13卷 855-878页

作者： israel Bekele Ethiopian Institute of Agricultural Research Melkassa Agricultural Research Center Adama Ethiopia

The use of balanced fertilizers in adequate amount is very important to increase crop productivity and production in Ethiopia. The study was executed to quantify maize (Zea mays L.) grain yield response to different rates of nitrogen (N), phosphorus (P), potassium (K) and sulfur (S) under balanced fertilization of other nutrients. On farm trials were conducted at seven sites on 8 farmers’ fields in Negele Arsi districts, west Arsi zone of Oromia region for three consecutive cropping seasons (2014-2016). Six rates of N, P, S and eight rates of K treatments established separately for each nutrient were laid out in randomized complete block (RCB) design with three replicates per farm. Nutrient response function modelling showed that 184, 20 and 80 kg•ha−1 were the agronomic optimum rate for N, P, and K, respectively. mean agronomic efficiency (AE) of N, P and K were recorded at the lower rates of these nutrients, application of 46, 10 and 20 kg•ha−1 N, P and K resulted in 19.1, 61.0, and 24 kg additional grain yield•kg−1 N, P and K, respectively. Also, the mean partial factor productivity (PFP) of N, P and K were 77.6, 370 and 158 kg additional grain•kg−1 applied N, P and K respectively. Economically optimal rate (EOR) of N, P and K were 48 - 114 kg•ha−1 N with CP 8 - 3.5, 12 - 20 kg•ha−1 P with CP 18 - 4.5 and 32 - 53 kg•ha−1 K with CP 8-4, from these rates net returns of US$487.23 - 143.30, US$698.16 - 498.3 and US$359.31 - 193.63 could be obtained respectively. To conclude, application of 84, 12 and 40 kg•ha−1 N, P and K could be recommended for the production of maize.

关键词： Agronomic Efficiency Balanced Fertilization Economic Optimal Rate maize Yield Nutrient Response Function Partial Factor Productivity