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Influence of Tropical Cyclones on hong Kong Air Quality

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Advances in Atmos.h.ric sciences 2018年第9期35卷 1177-1188页

作者： Eric C.h.ChOW Richard C.Y.LI Wen ZhOU City University of hong Kong(shenzhen)Research Institute Shenzhen 518057China Guy Carpenter Asia-Pacific Climate Impact Center s.h.ol of Energy and Environment City University of Hong KongHong KongChina

Tropical cyclones（TCs） constitute one of the major atmos.h.ric activities affecting the air quality of the Pearl River Delta region. In this study, the impact of TCs on air quality in hong Kong during the TC active season（July–October） from 2000 to 2015 is investigated. It is found that 57.5% of days with concentration of particulate matter with an aerodynamic diameter 10 μm（PM（10）） above the 90th percentile are related to TC activity. TCs in three regions, located to the east, southeast, and southwest of hong Kong, have obvious impacts on pollutant concentration. When TCs are located east of hong Kong near Taiwan, 65.5%/38.7% of the days.h.ve high or extremely high PM（10）/ozone（O3） levels, which are associated with northerly wind, sinking motion, and relatively low precipitation. When TCs are located southeast of hong Kong, 48.1%/58.2% of the days.h.ve high pollution levels, associated mainly with continental air mass transport. When TCs are south or west of hong Kong, only 20.8%/16.9% of the days.h.ve high PM（10）/O3 levels, and the air quality in hong Kong is generally good or normal due to TC-associated precipitation, oceanic air mass transport, and an enhanced rising motion. The higher chance of high O3 days when TCs are present between hong Kong and Taiwan, possibly due to lower-than-normal precipitation along the east coast of China under TC circulation. The results in this study highlight the important influence of TC position and associated atmos.h.ric circulations on the air quality in hong Kong.

关键词： PM10 03 air quality hK TC

AdaptiveMutate:a technique for privacy preservation

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Digital Communications and Networks 2019年第4期5卷 245-255页

作者： Louma Chaddad Ali Chehab Imad h.Elhajj Ayman Kayssi Department of Electrical and Computer Engineering American University of BeirutBeirut11072020Lebanon

Mobile apps are known to be rich sources for gathering privacy-sensitive information about smartphone *** the presence of encryption,passive network adversaries who have access to the network infrastructure can eavesdrop on the traffic and therefore fingerprint a user’s app by means of packet-level traffic *** it is difficult to prevent the adversaries from accessing the network,providing secrecy in hostile environments becomes a serious *** this study,we propose AdaptiveMutate,a privacy-leak thwarting technique to defend against the statistical traffic analysis of ***,we present a method for the identification of mobile apps using traffic ***,we propose a confusion system in which we obfuscate packet lengths,and/or inter-arrival time information leaked by the mobile traffic to make it hard for intruders to differentiate between the altered app traffic and the actual one using statistical *** aim is to shape one class of app traffic to obscure its features with the minimum *** system strives to dynamically maximize its efficiency by matching each app with the corresponding most dissimilar ***,AdaptiveMutate has an adaptive capability that allows it to choose the most suitable feature to mutate,depending on the type of apps analyzed and the classifier used,if *** evaluate the efficiency of our model by conducting a comprehensive simulation analysis that mutates different apps to each other using *** conclude that our algorithm is most efficient when we mutate a feature of one app to its most dissimilar one in another *** applying the identification technique,we achieve a classification accuracy of 91.1%.Then,using our obfuscation technique,we are able to reduce this accuracy to 7%.Also,we test our algorithm against a recently published approach for mobile apps classification and we are able to reduce its accuracy from 94.8%to 17.9%.Additionally,we analyze the tradeoff betwe

关键词： side-channel information App profiling Obfuscation Traffic classification Packet length statistics Inter-arrival time

Probing calcium and sulfur distribution and pattern in hairs using micro-proton induced X-ray emission (MPIXE)

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Chinese science Bulletin 2007年第21期52卷 2909-2912页

作者： TONG YongPeng LI ChangMing John h.T. LUONG Nuclear Technical Institute Shenzhen University Shenzhen 518060 China s.h.ol of Chemical and Biomedical Engineering Nanyang Technological University Singapore Biotechnology Research Institute National Research (3ouncil of Canada Montreal: Quebec Canada H4P 2R2

More than 20 hair strands obtained from several people are analyzed by non-invasive micro-proton induced X-ray emission (PIXE) for probing calcium and sulfur distribution and pattern. The sulfur con- tent in woman’s.h.ir along the longitudinal axis shows a monthly rhythm whereas the level of Ca is much higher in the medulla core and exhibits a daily rhythm both in male and female hair. The Ca content gradually decreases from the tip to the root position in the shedding process and more Ca can be found in black hair compared to white hair.

关键词：质子诱导X射线发射钙硫磺毛发

hydrogen and Ozone sAW Based Gas sensors with RF Magnetron sputtered InO_x and Electron Beam Evaporated siN_y

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稀有金属材料与工程 2006年第A03期35卷 206-209页

作者： A.C.Fechete A.Wisitsora-at W.Wlodarskil K.Kalantar-zadeh s.Kandasamy A.s.h.lland sensor Technology Laboratory School of Electrical & Computer EngineeringRMIT UniversityMelbourne V1C 3001Australia NECTEC 112 Thailand Science ParkKIong LuangPathumathani 12120Thailand sensor Technology Laboratory School of Electrical & Computer EngineeringRMIT UniversityMelbourne VIC 3001Australia

Layered surface Acoustic Wave (sAW) devices with an InO_x/siN_u/36°YX LiTaO_3 structure were investigated for sensing low concentrations of hydrogen (h_2) and ozone (O_3) at different operating *** sensor consists of a 1μm thick silicon nitride (siN_y) intermediate layer deposited by electron beam evaporation on a 36°Y-cut X-propagating piezoelectric lithium tantalate (LiTaO_3) substrate and a 100 nm thin indium oxide (InO_x) sensing layer deposited by *** *** device fabrication is described and the performance of the sensor is analyzed in terms of response magnitude as a function of operating *** frequency shifts of 360 khz for 600μg/g of h_2 and 92 khz for 40 ng/g O_3 were *** addition,the surface morphology of the deposited films were investigated by Atomic Force Microscopy (AFM) and the chemical composition by X-Ray Photoelectron spectroscopy (XPs) to correlate gas-sensing behavior to structural characteristics of the thin film.

关键词： sAW gas sensors E-beam evaporated siN_y InO_x O3 h2

shrinkage of magnetos.h.re observed by TC-1 satellite during the high-speed solar wind stream

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science China(Technological sciences) 2008年第10期51卷 1695-1703页

作者： h. RME I. DANDOURAs C. M. CARR Centre d'Etude spatiale des Rayonnements BP 4346 31028 Toulouse cedex 4 France The Blackett Laboratory Imperial College London SW7 2BZ UK

During the interval 06:14―07:30 UT on August 24, 2005, since the Earth’s magneto- pause was suddenly compressed by the persistent high-speed solar wind stream with the southward component of the interplanetary magnetic field (IMF), the magnetopause moved inward for about 3.1 RE. Meanwhile, TC-1 satellite shifted from northern plasma sheet to the northern lobe/mantle region, although it kept inward flying during the interval 06:00―07:30UT. The shift of TC-1 from the plasma sheet to the lobe/mantle is caused by the simultaneous inward displacements of the plasma sheet and near-Earth lobe/mantle region, and their inward movement velocity is larger than the inward motion velocity of TC-1. The joint inward dis-placements of the magnetopause, the lobe/mantle region and the plasma sheet indicate that the whole magnetos.h.re shrinks inward due to the magnetos.h.ric compression by the high-speed solar wind stream, and the magnetos.h.ric ions are attached to the magnetic field lines (i.e. ‘frozen’ in magnetic field) and move inward in the shrinking process of magnetos.h.re. The large shrinkage of magne-tos.h.re indicates that the near-Earth magnetotail compression caused by the strong solar wind dynamic pressure is much larger than its thickening caused by the southward component of the IMF, and the locations of magnetos.h.ric regions with different plasmas vary remarkably with the variation of the solar wind dynamic pressure.

关键词： solar wind dynamic pressure shrinkage of magnetos.h.re storm sudden commencement substorm

Event-by-Event simulation of the hanbury Brown-Twiss Experiment with Coherent Light

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Communications in Computational Physics 2010年第4期7卷 813-830页

作者： F.Jin h.De Raedt K.Michielsen Department of Applied Physics Zernike Institute for Advanced MaterialsUniversity of GroningenNijenborgh 4NL-9747 AG GroningenThe Netherlands Institute for Advanced simulation Julich Supercomputing CentreResearch Centre JuelichD-52425 JuelichGermany

We present a computer simulation model for the hanbury Brown-Twiss experiment that is entirely particle-based and reproduces the results of wave theory. Themodel is solely based on experimental facts, satisfies Einstein’s criterion of local causality and does not require knowledge of the solution of a wave equation. The simulationmodel is fully consistent with earlier work and provides another demonstration thatit is possible to give a particle-only description of wave phenomena, rendering theconcept of wave-particle duality superfluous.

关键词： Computational techniques hanbury Brown-Twiss effect light coherence light interference quantum theory

Comparison of approaches to quantify sARs-CoV-2 in wastewater using RT-qPCR: Results and implications from a collaborative inter-laboratory study in Canada

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Journal of Environmental sciences 2021年第9期33卷 218-229页

作者： Alex h.s.Chik Melissa B.Glier Mark servos Chand s.Mangat Xiao-Li Pang Yuanyuan Qiu Patrick M.D’Aoust Jean-Baptiste Burnet Robert Delatolla sarah Dorner Qiudi Geng John P.Giesy Jr Robert Mike McKay Michael R.Mulvey Natalie Prystajecky Nivetha srikanthan Yuwei Xie Bernadette Conant steve E.hrudey Canadian sARs-CoV-Inter-Laboratory Consortium Consultant to Canadian Water Network Inc. KitchenerCanada Presently at Ontario Clean Water Agency MississaugaCanada Environmental Microbiology BC Centre for Disease ControlVancouverCanada Department of Biology University of WaterlooWaterlooCanada National Microbiology Laboratory Public Health Agency of CanadaWinnipegCanada Public health Laboratory Alberta Precision LaboratoryEdmontonCanada Department of Laboratory Medicine&Pathology Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAB T6G 2G3Canada Faculty of Engineering University of OttawaOttawaCanada Département des génies civil géologique et des minesPolytechnique MontréalMontréalCanada Veterinary Biomedical sciences University of SaskatchewanSaskatoonCanada Toxicology Centre University of SaskatchewanSaskatoonCanada Great Lakes Institute for Environmental Research University of WindsorWindsorCanada Department of Medical Microbiology University of ManitobaWinnipegCanada Department of Pathology and Laboratory Medicine University of British ColumbiaVancouverCanada Canadian Water Network Inc. WaterlooCanada Group author details below

Detection of sARs-CoV-2 RNA in wastewater is a promising tool for informing public health decisions during the COVID-19 ***,approaches for its analysis by use of reverse transcription quantitative polymerase chain reaction(RT-q PCR)are still far from standardized *** characterize inter-and intra-laboratory variability among results when using various methods deployed across Canada,aliquots from a real wastewater sample were spiked with surrogates of sARs-CoV-2(gamma-radiation inactivated sARs-CoV-2 and human coronavirus strain 229E[hCoV-229E])at low and high levels then provided"blind"to eight *** estimates reported by individual laboratories were consistently within a 1.0-log_(10) range for aliquots of the same spiked *** laboratories distinguished between low-and high-spikes for both *** expected,greater variability was observed in the results amongst laboratories than within individual laboratories,but sARs-CoV-2 RNA concentration estimates for each spiked condition remained mostly within 1.0-log_(10) *** no-spike wastewater aliquots provided yielded non-detects or trace levels(s/mL)of sARs-CoV-2 *** appear linked to methods that included or focused on the solids fraction of the wastewater matrix and might represent in-situ sARs-CoV-2 to the wastewater ***-229E RNA was not detected in the no-spike ***,all methods yielded comparable results at the conditions *** behavior of sARs-CoV-2 and spiked surrogates in wastewater should be considered to evaluate method effectiveness.A consistent method and laboratory to explore wastewater sARs-CoV-2 temporal trends for a given system,with appropriate quality control protocols and documented in adequate detail should succeed.

关键词： COVID-19 Wastewater surveillance Public health Quality assurance Quality control

AN ADAPTIVE EFG-FE COUPLING METhOD FOR ThE NUMERICAL sIMULATION OF EXTRUsION PROCEssEs

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Acta Metallurgica sinica(English Letters) 2008年第5期21卷 380-388页

作者： L.C. Liu X.h. Doug C.X. Li National Die ＆ Mold CAD Engineering Research Center Shanghai Jiaotong University Shanghai 200030 China

An adaptive EFG-FE coupling method is proposed and developed for the numerical simulation of lateral extrusion and forward-backward extrusion. Initially, the simulation has been implemented by using a conventional FE model. During the deforming process, mesh quality is checked at every incremental step. Distorted elements are automatically converted to EFG nodes, whereas, the less distorted elements are reserved. A new algorithm to generate EFG nodes and interface elements is presented. This method is capable of dealing with large deformation and has.h.gher computational efficiency than using an EFG method wholly. Numerical results demonstrate that the adaptive EFG-FE coupling method has reasonable accuracy and is effective for local bulk metal forming such as extrusion processes.

关键词： Meshless method Coupling method Numerical simulation Extrusion process

The Petrov–Galerkin finite element method for the numerical solution of time-fractional sharma–Tasso–Olver equation

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International Journal of Modeling, simulation, and scientific Computing 2019年第1期10卷 95-105页

作者： A.K.Gupta s.s.h. Ray KIIT University School of Applied Sciences Bhubaneswar 751024India National Institute of Technology Department of Mathematics Rourkela 769008 India

In this paper,time-fractional sharma-Tasso-Olver(sTO)equation has been solved numerically through the Petrov-Galerkin approach utilizing a quintic B-spline function as the test function and a linear hat function as the trial *** Petrov-Galerkin technique is effectively implemented to the fractional sTO equation for acquiring the approximate solution *** numerical outcomes are observed in adequate compatibility with those obtained from variational iteration method(VIM)and exact *** fractional order,the numerical outcomes of fractional sharma-Tasso-Olver equations are also compared with those obtained by variational iteration method(VIM)in song et al.[song L.,Wang Q.,Zhang h.,Rational approximation solution of the fractional sharma-Tasso-Olver equation,***.224:210-218,2009].Numerical experiments exhibit the accuracy and efficiency of the approach in order to solve nonlinear fractional sTO equation.

关键词： Fractional sharma-Tasso-Olver equation Petrov-Galerkin method B-spline Grunwald-Letnikov fractional derivative