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The Air Pollution Concern within the Holy Prophet Mosque in *** AI-Munawarah

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Journal of Environmental science and Engineering 2011年第5期5卷 550-556页

作者： A.A. Bazzaz A.K. Al-Juhani n.s. Al-Erwi K.n. Kurdi Department of Biology Faculty of Sciences University of Taibah Al-Madinah Al-Munawarah （POB 344） KSA Laboratory of Al-Madinah Al-Munawarah Municipality KSA.

Using air pollution detecting equipmen.s.ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Prophet Mosque in Al-Madinah A l-Munawarah from early 12：00 to 14：00 of Friday and from 19：00 to 22：30 at holy month, Ramadan. The percentage of both carbon monoxide （CO） and nitrogen dioxide （nO2） had significantly increased （p 〈 0.05-0.005）. The peak levels of these air pollutan.s.were between 13：15-13：20 during Fridays. The increase in the emission of these exhausted gases was concomitant with the significant decrease （p 〈 0.05） in oxygen （02） levels but the latter recovered its levels after 13：20 hours. The arithmetic total mean density of vehicle per minute （vpm） at salam Road, the busiest road of Al-Madinah, during hours （07：00-09：00）, （13：00-15：00） and （17：00-19：00） of both Friday and saturdays respectively were （8/45, 16/40 and 36/43）. The increase in air pollution has been attributed to a dramatic increase in number of public cars use the car parks during these times, the consequent congestion at entries, the excess or/and poor consumption of fuels being utilized and the inadequate ventilation.

关键词： Air pollution holy prophet mosque Al-Madinah Al-Munawarah.

CFD simulation of helicopter rotor flow based on unsteady actuator disk model

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Chin.s. Journal of Aeronautics 2020年第9期33卷 2313-2328页

作者： G.n.BARAKOs T.FITZGIBBOn A.n.KUsYUMOV s.A.KUsYUMOV s.A.MIKHAILOV James Watt school of Engineering Glasgow UniversityGlasgow G128QQUnited Kingdom Department of Aerohydrodynamics Kazan National Research Technical University named after A.N.TupolevKazan 420111Russia

Actuator Disks(AD)can provide characterizations of rotor wakes while reducing computational expense associated with modeling the fully resolved *** work presen.s.an unsteady actuator disk method based on.s.rface circulation distribution combined with empirical data,blade element theory and rotor momentum *** nonuniform circulation distribution accoun.s.for 3 D blade load effects,and in particular,tip *** simulations were conducted for the isolated pressure sensitive paint model rotor blade in hover and forward flight using the HMB3 CFD solver of Glasgow *** of CFD results in comparison with published numerical data was performed in hover,for a range of blade pitch angles using fully turbulent flow and the k-x ssT *** forward flight,the vortex structures predicted using the unsteady actuator disk model showed configurations similar to the on.s.obtained using fully resolved rotor *** the reduced grid cells number,the CFD results for AD models captured well the main vortical structures around the rotor disk in comparison to the fully resolved cases.

关键词： CFD Fully resolved blades rotor PsP rotor surface circulation distribution Unsteady actuator disk model

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano sergei A.Kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIs) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of neuroscience and Regenerative Medicine&Department of neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findin.s.indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by n-methyl-D-aspartate *** n-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system n transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through n-methyl-D-aspartate receptor ***,previously unrecognized mechan.s.s involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling n-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Influence of thermomechanical processing on microstructure,mechanical and strain hardening properties of single-phase Mg-4Li-0.5Ca alloy for structural application

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Journal of Magn.s.um and Alloys 2020年第4期8卷 1262-1268页

作者： n.s.iraman.s.Kumaran.s.thiya narayanan n school of Mechanical Engineering SASTRA Deemed to be University ThirumalaisamudramThanjavurTamilnadu 613401India Department of Metallurgical and Materials Engineering National Institute of Technology TiruchirappalliTamil Nadu 620015India

The single-phase Mg-4Li-0.5Ca alloy was rolled at three different temperatures(250,300 and 350℃)and followed by annealing at 200°C for 10 *** evaluate the mechanical properties,the tensile test was conducted at a constant strain rate of 10^(-3)s^(-1).Factors influencing the tensile strength and strain hardening properties were assessed by microscopy,XRD and EBsD ***,Kocks-Mecking plots(K-M)were used to determine the different stages of strain hardening exhibited by the variously processed Mg-4Li-0.5Ca alloy test *** ultimate tensile strength has decreased as hot-rolling temperature in creases with increased *** strain hardening properties such as hardening capacity(Hc),strain hardening exponent(n)are increased significantly with an increase in hot rolling temperature and subsequent annealing.

关键词： Mg-4Li-0.5Ca Hot rolling Twins Mg2Ca Hardening capacity

TWO-DIMEnsIOnAL APPROXIMATIOnOF EIGEnVALUE PROBLEMs In.s.ELL THEORY:FLEXURAL sHELLs

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Chin.s. Annals of Mathematics,series B 2000年第1期21卷 1-16页

作者： s.KEsAVAn n.s.BU InstituteofMathematicalsciences C.I.T.CampusTaramaniChennai-600113India.

The eigenvalue problem for a thin linearly elastic shell, of thickn.s. 2c, clamped along its lateral surface is considered. Under the geometric assumption on the middle surface of the shell that the space of inextensional displacemen.s.is non-trivial, the authors obtain, as e - 0, the eigenvalue problem for the two-dimensional "flexural shell" model if the dimension of the space is infinite. If the space is finite dimensional, the limits of the eigenvalues could belong to the spectra of both flexural and membrane shells. The method consists of rescaling the variables and studying the problem over a fixed domain. The principal difficulty lies in obtaining suitable a priori estimates for the scaled eigenvalues.

关键词： Approximation Eigenvalue problem shell theory Flexural shells

Conversion of an atomic to a molecular argon ion and low pressure argon relaxation

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Chin.s. Physics B 2016年第1期25卷 697-705页

作者： M n.s.ankov A P Jovanovie V Lj Markovic s n.s.amenkovic Department of Physics Faculty of Sciences and MathematicsUniversity of Ni Viegradska 33Ni 18001Serbia

The dominant process in relaxation of DC glow discharge between two plane parallel electrodes in argon at pressure 200 Pa is analyzed by measuring the breakdown time delay and by analytical and numerical models. By using the approx- imate analytical model it is found that the relaxation in a range from 20 to 60 ms in afterglow is dominated by Ar＋ ions, produced by atomic-to-molecular conversion of Ar＋ ions in the first several millisecon.s.after the cessation of the discharge. This conversion is confirmed by the presence of double-Gaussian distribution for the formative time delay, as well as con- version maxima in a set of memory curves measured in different conditions. Finally, the numerical one-dimensional （1D） model for determining the number densities of dominant particles in.s.ationary DC glow discharge and two-dimensional （2D） model for the relaxation are used to confirm the previous assumptions and to determine the corresponding collision and transport coefficien.s.of dominant species and processes.

关键词： argon discharge afterglow relaxation fluid model plasma reactions

Effect of surface blowing on aerodynamic characteristics of tubercled straight wing

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Chin.s. Journal of Aeronautics 2019年第5期32卷 1111-1120页

作者： n.GAn.s. s.ARUnVInTHAn.s.nADARAJA PILLAI Turbulence and Flow Control Lab School of Mechanical Engineering SASTRA Deemed University

Recent research proves that win.s.with leading-edge tubercles have the ability to perform efficiently in post-stall region over the conventional straight wing. Moreover, the conventional straight wing outperforms the tubercled wing at a pre-stall region which is quintessential. Even though tubercled wing offers great performance enhancement, because of the complexity of the flow, the trough region of the tubercled wing is more prone to flow separation. Henceforth, the present paper aims at surface blowing – an active flow control technique over the tubercled wing to enhance the aerodynamic efficiency by positively influencing its lift characteristics without causing any additional drag penalty. Flow parameters like blowing velocity ratios and the location of blowing were chosen to find the optimised configuration keeping the amplitude and frequency of the leading-edge tubercles constant as 0.12 c and 0.25 c respectively. numerical investigations were carried out over the baseline tubercled wing and tubercled wing with surface blowing at various blowing jet velocity ratios 0.5, 1 and 2 over four different chordwise locations ranging from 0.3 c to 0.8 *** results confirm that blowing at various x/c with different blowing velocity ratios performs better than the conventional tubercled wing. Comparatively, blowing velocity ratio 2 at 0.3 c shows peak performance of about 28% enhancement in the lift characteristics relative to the baseline model. Particularly, in the pre-stall region, 25–50% increase in aerodynamic efficiency is evident over the tubercled wing with surface blowing compared with the baseline case. Additionally,attempts were made to delineate the physical significance of the flow separation mechan.s. due to blowing by visualizing the streamline pattern.

关键词： Active flow control Aerodynamic efficiency Biomimetics Blowing Tubercles

Using mixed integer programming and airborne laser scanning to generate forest management units

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Journal of Forestry Research 2022年第1期33卷 217-226页

作者： Adrián Pascual sándor FTóth Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349-017 LisboaPortugal school of Forest sciences University of Eastern FinlandP.O.Box 11180101 JoensuuFinland school of Environmental and Forest sciences University of WashingtonSeattleWAUSA

Airborne laser scanning(ALs)has been widely applied to estimate tree and forest attributes,but it can also drive the segmentation of forest *** algorithms are the dominant technique in.s.gmentation but spatial optimization using exact methods remains *** study presen.s.a novel approach to segmentation based on mixed integer programming to create forest management units(FMUs).This investigation focuses on using raster information derived from ALs *** mainstream clustering algorithms were compared to the new MIP formula that simultaneously accoun.s.for area and adjacency restrictions,FMUs size and homogeneity in terms of vegetation *** optimal problem solution was found when using less than 150 cells,showing the problem formulation is *** results for MIP were better than for the clustering algorithms;FMUs were more compact based on the intravariation of canopy height and the variability in.s.ze was *** MIP model allows the user to strictly control the size of FMUs,which is not possible in heuristic optimization and in the clustering algorithms *** definition of forest management units based on remote sensing data is an important operation and our study pioneers the use of MIP ALs-based optimal segmentation.

关键词： segmentation Precision forestry Optimization Mathematical programming Airborne laser scanning

software Vulnerabilities Overview:A Descriptive study

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Tsinghua science and Technology 2020年第2期25卷 270-280页

作者： Mario Calín.s.nchez Juan Manuel Carrillo de Gea José Luis Fernández-Alemán Jesús Garcerán Ambrosio Toval the Department of Informatics and systems Faculty of Computer ScienceUniversity of Murcia

Computer security is a matter of great *** the last decade there have been numerous cases of cybercrime based on the exploitation of software *** fact has generated a great social concern and a greater importance of computer security as a *** this work,the most important vulnerabilities of recent years are identified,classified,and categorized individually.A measure of the impact of each vulnerability is used to carry out this classification,considering the number of products affected by each vulnerability,as well as its *** addition,the categories of vulnerabilities that have the greatest presence are *** on the results obtained in this study,we can understand the consequences of the most common vulnerabilities,which software products are affected,how to counteract these vulnerabilities,and what their current trend is.

关键词： descriptive study software security software vulnerabilities vulnerability databases