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Arctic source for elevated atmospheric mercury(Hg^0) in the western Bering sea in the summer of 2013

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Journal of Environmental sciences 2018年第6期30卷 114-121页

作者： V.V.Kalinchuk V.F.Mishukov A.s.Astakhov V.I.Il'ichev Pacific Oceanological Institute of Far Eastern Branch of Russian Academy of sciences Vladivostok Russia

Measurements of gaseous elemental mercury（Hg^0） in the marine boundary layer of the western Bering sea were performed using an automatic mercury analyzer RA 915 ＋（Ltd. ＂Lumex＂, st. Petersburg, Russia） aboard the Russian research vessel Academician *** from 3 to 20 August 2013. Hg^0 concentrations varied from 0.3 to 2.1 ng/m^3（n = 4783）;the average value（1.1 ± 0.3 ng/m^3） was lower than both the background range of the Northern Hemisphere（1.5–1.7 ng/m^3） and average values previously observed in the Bering sea, and corresponded to the background concentrations of the southern Hemisphere（1.1–1.3 ng/m^3）.Maximum Hg^0 concentrations were observed within air masses that came from the lower troposphere of the central Arctic. Under these conditions, Hg^0 ranged between 1.1 and 2.1 ng/m^3 with an average of 1.5 ± 0.2 ng/m^3（n = 1183）. Except for these periods, Hg^0 concentrations during the rest of the study varied from 0.3 to 1.8 ng/m^3, with an average value of 1.0 ± 0.2 ng/m^3（n = 3600）. Our results support the hypothesis that, in the summer, air masses from the central Arctic Ocean can be an exporter of mercury to lower latitudes. Perhaps the atmospheric transport of elevated concentrations of Hg^0 into lower latitudes may have implications for the biologic and economic health of important fisheries, such as the Bering sea.

关键词： Mercury Atmosphere Long-range transport Bering sea Arctic

Mixed H_∞ and Passive Projective synchronization for Fractional Order Memristor-Based Neural Networks with Time-Delay and Parameter Uncertainty

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Communications in Theoretical Physics 2017年第10期67卷 483-494页

作者：宋晓娜宋帅 Inés Tejado Balsera 刘磊坡 school of Information Engineering Henan University of Science and Technology Industrial Engineering school University of Extremadura

This paper investigates the mixed Ho~ and passive projective synchronization problem for fractional-order （FO） memristor-based neural networks. Our aim is to design a controller such that, though the unavoidable phenomena of time-delay and parameter uncertainty are fully considered, the resulting closed-loop system is asymptotically stable with a mixed H∞ and passive performance level. By combining active and adaptive control methods, a novel hybrid control strategy is designed, which can guarantee the robust stability of the closed-loop system and also ensure a mixed H∞ and passive performance level. Via the application of FO Lyapunov stability theory, the projective synchronization conditions are addressed in terms of linear matrix inequaiity techniques. Finally, two simulation examples are given to illustrate the effectiveness of the proposed method.

关键词： H∞ and passive performance fractional-order memristor-based neural networks adaptive pro-jective synchronization time delay uncertain parameters

Metabolic cost of level,uphill,and downhill running in highly cushioned shoes with carbon-fiber plates

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Journal of sport and Health science 2022年第3期11卷 303-308页

作者： Clarissa s.Whiting Wouter Hoogkamer Rodger Kram Locomotion Laboratory Department of Integrative PhysiologyUniversity of ColoradoBoulderCO 80309USA Integrative Locomotion Lab Department of KinesiologyUniversity of MassachusettsAmherstMA 01003USA

Background:Compared to conventional racing shoes,Nike Vaporfly 4% running shoes reduce the metabolic cost of level treadmill running by4%.The reduction is attributed to their lightweight,highly compliant,and resilient midsole foam and a midsole-embedded curved carbon-fiber *** investigated whether these shoes also could reduce the metabolic cost of moderate uphill(+3°) and downhill(-3°) *** tested the null hypothesis that,compared to conventional racing shoes,highly cushioned shoes with carbon-fiber plates would impart the same ~4%metabolic power(W/kg) savings during uphill and downhill running as they do during level ***:After familiarization,16 competitive male runners performed six 5-min trials(2 shoes × 3 grades) in 2 Nike marathon racing-shoe models(streak 6 and Vaporfly 4%) on a level,uphill(+3°),and downhill(-3°) treadmill at 13 km/h(3.61 m/s).We measured submaximal oxygen uptake and carbon dioxide production during Minutes 4-5 and calculated metabolic power(W/kg) for each shoe model and grade ***:Compared to the conventional shoes(streak 6),the metabolic power in the Vaporfly 4% shoes was 3.83%(level),2.82%(uphill),and2.70%(downhill)less(all p s less compared to level running(p=0.04;effect size(Es)=0.561) but was not statistically different between downhill and level running(p=0.17;Es=0.356).Conclusion:On a running course with uphill and downhill sections,the metabolic savings and hence performance enhancement provided by Vaporfly 4% shoes would likely be slightly less overall,compared to the savings on a perfectly level race course.

关键词： Energetics Incline Locomotion Oxygen consumption Running economy

Predicting individuals’vulnerability to social engineering in social networks

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Cybersecurity 2018年第1期1卷 710-728页

作者： samar Muslah Albladi George R.s.Weir College of Computer science and Engineering University of JeddahJeddahKingdom of Saudi Arabia Department of Computer and Information sciences University of StrathclydeGlasgowUK

The popularity of social networking sites has attracted billions of users to engage and share their information on these *** vast amount of circulating data and information expose these networks to several security *** engineering is one of the most common types of threat that may face social network *** and increasing users’awareness of such threats is essential for maintaining continuous and safe use of social networking *** the most vulnerable users in order to target them for these training programs is desirable for increasing the effectiveness of such *** studies have investigated the effect of individuals’characteristics on predicting their vulnerability to social engineering in the context of social *** address this gap,the present study developed a novel model to predict user vulnerability based on several perspectives of user *** proposed model includes interactions between different social network-oriented factors such as level of involvement in the network,motivation to use the network,and competence in dealing with threats on the *** results of this research indicate that most of the considered user characteristics are factors that influence user vulnerability either directly or ***,the present study provides evidence that individuals’characteristics can identify vulnerable users so that these risks can be considered when designing training and awareness programs.

关键词： Deception Information security Phishing social engineering social network Vulnerability

Adaptive Increasing-Order synchronization and Anti-synchronization of Chaotic systems with Uncertain Parameters

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Chinese Physics Letters 2011年第11期28卷 49-51页

作者： M.Mossa Al-sawalha M.s.M.Noorani Faculty of science Mathematics DepartmentUniversity of HailKingdom of Saudi Arabia Center for Modelling&Data Analysis School of Mathematical SciencesUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

We elaborate the concept of increasing-order synchronization and anti-synchronization of chaotic systems via an adaptive control scheme and modulation *** is shown that the dynamical evolution of a third-order chaotic system can be synchronized and anti-synchronized with a fourth-order chaotic system even though their parameters are *** analysis and numerical simulations are carried out to verify the results.

关键词： parameters chaotic system

Flow of Oldroyd-B fluid with nanoparticles and thermal radiation

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Applied Mathematics and Mechanics(English Edition) 2015年第1期36卷 69-80页

作者： T.HAYAT T.HUssAIN s.A.sHEHZAD A.ALsAEDI Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of ScienceKing Abdulaziz University Department of Mathematics Faculty of Computing Mohammad Ali Jinnah University Department of Mathematics COMSATS Institute of Information Technology

The two-dimensional boundary layer flow of an Oldroyd-B fluid in the presence of nanoparticles is investigated. Convective heat and mass conditions are considered in the presence of thermal radiation and heat generation. The Brownian motion and thermophoresis effects are retained. The nonlinear partial differential equations are reduced into the ordinary differential equation （ODE） systems. The resulting ODE systems are solved for the series solutions. The results are analyzed for various physical parameters of interest. Numerical values of the local Nusselt and sherwood numbers are also computed and analyzed.

关键词： nanoparticle Oldroyd-B fluid heat generation convective condition

深度学习算法在锥束CT中检测和三维分割颌面骨病变的研究

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国际医学放射学杂志 2024年第1期 123-124页

作者： T.Yeshua s.Ladyzhensky A.Abu-Nasse R.Abdalla-Aslan T.Boharon A.Itzhak-Pur 李彤巍

摘要目的开发自动化的深度学习算法并用于在颌面部锥形束CT(CBCT)扫描来检测和三维分割偶然发现的骨病变。方法该数据集包括82个CBCT扫描，其中41个经组

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Carbon Nanoparticles in Nematic Liquid Crystals

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Chinese Physics Letters 2008年第1期25卷 212-215页

作者： s. Eren san Mustafa Okutan Oguz Koysal Yusuf Yerli Department of Physics Gebze Institute of Technology PO Box 141 Gebze 41400 Kocaeli Turkey

Fullerene C60, C7o, single-walled and multi-walled carbon nanotubes and graphene sheets are doped to nematic liquid crystal （LC） host in the same percentage. Planar samples of these mixtures are prepared and our measurements constitute an optimization basis for possible applications. Fullerene balls are found to be the best compatible material for optical aims and reorientation of LC molecules, while the carbon nanotubes experience some reorientation possibility in LC media and graphene layers are good barriers to preserve reorientation.

关键词： pulsars x-ray spectra relativity and gravitation redshift

Effects of thermophoresis and thermal radiation in mixed convection three-dimensional flow of Jeffrey fluid

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Applied Mathematics and Mechanics(English Edition) 2015年第5期36卷 655-668页

作者： s.A.sHEHZAD T.HAYAT A.ALsAEDI B.AHMAD Department of Mathematics Comsats Institute of Information Technology Department of Mathematics Quaid-i-Azam University Department of Mathematics Faculty of Science King Abdulaziz University

Mixed convection three-dimensional flow of Jeffrey fluid is studied in the presence of thermal radiation and thermophoresis. The relevant problems are formulated,and series solutions are presented for velocities, temperature, and concentration. Convergence of series solutions is obtained graphically and numerically. Effects of different emerging parameters on the velocities, temperature, and concentration fields are plotted and discussed.

关键词： convection formulated Jeffrey Prandtl convergent admissible illustrate relaxation stretching numerically