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Estimating the instantaneous reproduction number(R_(t))by using particle filter

Infectious Disease Modelling 2023年第4期8卷 1002-1014页

作者： yong sul won Woo-Sik Son Sunhwa Choi Jong-Hoon Kim National Institute for Mathematical Sciences DaejeonSouth Korea International Vaccine Institute SeoulSouth Korea

Background:Monitoring the transmission of coronavirus disease 2019(COVID-19)requires accurate estimation of the effective reproduction number(Rt).However,existing methods for calculating Rt may yield biased estimates if important real-world factors,such as delays in confirmation,pre-symptomatic transmissions,or imperfect data observation,are not ***:To include real-world factors,we expanded the susceptible-exposed-infectiousrecovered(SEIR)model by incorporating pre-symptomatic(P)and asymptomatic(A)states,creating the SEPIAR *** utilizing both stochastic and deterministic versions of the model,and incorporating predetermined time series of Rt,we generated simulated datasets that simulate real-world challenges in estimating *** then compared the performance of our proposed particle filtering method for estimating Rt with the existing EpiEstim approach based on renewal ***:The particle filtering method accurately estimated Rt even in the presence of data with delays,pre-symptomatic transmission,and imperfect *** evaluating via the root mean square error(RMSE)metric,the performance of the particle filtering method was better in general and was comparable to the EpiEstim approach if perfectly deconvolved infection time series were provided,and substantially better when Rt exhibited short-term fluctuations and the data was right ***:The SEPIAR model,in conjunction with the particle filtering method,offers a reliable tool for predicting the transmission trend of COVID-19 and assessing the impact of intervention *** approach enables enhanced monitoring of COVID-19 transmission and can inform public health policies aimed at controlling the spread of the disease.

关键词： Particle filter Sequential Monte Carlo Effective reproduction number COVID-19 Transmission model Compartment model

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Sensorless Control of IPMSM for Last 10 Years and Next 5 Years

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CES Transactions on Electrical Machines and Systems 2017年第2期1卷 91-99页

作者： Seung-Ki sul yong-Cheol Kwon Younggi Lee Electrical and Computer Engineering Department Seoul National University

This paper presents the developments of sensorless control of interior permanent magnet synchronous machine(IPMSM)for last 10 years,which could be divided into the past and the present for each 5 *** popular methods developed for last 10 years would be described and evaluated,and the limitations with the methods are *** the past a concept extended EMF(EEMF)was introduced and it can model IPMSM as a non-salient motor,meaning that the representation of IPMSM in the estimated rotor reference frame would be much simpler and ***,because it still relied on back EMF,standstill operation was ***,the position control of IPMSM could not be achieved with EEMF *** sensorless drive,the high-frequency signal injection method exploiting inherent saliency of IPMSM has been continuously developed for last 10 years and applied to various industry fields,where torque control at standstill is *** performance has been improved but there are still many problems to be *** the present,the square-wave signal injection at estimated d-axis has improved the control performance ***,there are strong demands to improve the control performance of sensorless drive,*** on the problems in the present,in this paper the possible developments of sensorless drive of IPMSM in next 5 years are enlightened as the future of sensorless control.

关键词： Back EMF extended EMF method high-frequency signal injection method interior permanent magnet synchronous motor review sensorless control

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Influence of annealing temperature on visible-light photocatalytic activities of Ag_(3)PO_(4) particulates synthesized using CH_(3)COOAg as a precursor

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Optoelectronics Letters 2018年第4期14卷 291-295页

作者： sul Mei-rong SUN Ya-nan GU Xiu-quan SHI Mei-lin WANG yong LIU Lin-lin School of Medical Imaging Xuzhou Medical UniversityXuzhou 221004China School of Materials Science and Engineering China University of Mining and TechnologyXuzhou 221116China

Ag_(3)PO_(4) microparticles(MPs)were prepared through a facile chemical precipitation route and using silver acetate(AgAc)as metal *** effect of annealing temperature(T_(a))and time(τ_(a))on the actual photocatalytic(PC)activity of Ag_(3)PO_(4) MPs is *** optimal annealing parameters are T_(a) of 400℃andτ_(a) of 90 *** enhanced PC activity by annealing at 400℃is ascribed to the increase of electron ***,an Ag_(3)PO_(4) photoelectrode was fabricated through a drop-coating deposition route,which demonstrates a photocurrent density of 80μA/cm^(2) and acceptable *** n-type conduction behavior of Ag_(3)PO_(4) is verified by a Mott-Schottky(M-S)plot.

关键词： A

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Occurrence of antibiotic resistance genes and bacterial pathogens in water and sediment in urban recreational water

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Journal of Environmental Sciences 2019年第3期31卷 65-74页

作者： Peiyan Dong Qijia Cui Tingting Fang yong Huang Hui Wang State Key Joint Laboratory on Environment Simulation and Pollution Control School of Environment Tsinghua University

The emergence and prevalence of antibiotic resistance genes(ARGs) and pathogens in the environment are serious global health concern. However, information about the occurrence of ARGs and pathogens in recreational water is still limited. Accordingly, we investigated the occurrence of six ARGs and human pathogens in three recreational lakes, and the correlations between ARGs and one mobile genetic element(intI1) were analyzed. The quantitative PCR results showed that the concentration of ARGs ranged from 4.58 × 10~0 to 5.0 × 10~5 copies/mL in water and from 5.78 × 10~3 to 5.89 × 10~8 copies/g dry weight(dw)in sediment. sul1 exhibited the highest level among the five quantifiable ARGs. The concentrations of sul1, bla_(-TEM), and tetX exhibited significant positive correlations with intI1(p sults showed that 68 genera of pathogens were present, among which Aeromonas, Mycobacterium, and Pseudomonas were the dominant ones in this region, posing a considerable potential health risk to public health. Overall, the widespread distribution of ARGs and pathogens underscores the need to better monitor and mitigate their propagation in recreational lakes and the associated risks to human health.

关键词： Recreational water ARGs Class 1 integron Pathogen diversity and concentration

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GIS-based spatial prediction of landslide using road factors and random forest for Sichuan-Tibet Highway

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Journal of Mountain Science 2022年第2期19卷 461-476页

作者： YE Cheng-ming WEI Rui-long GE yong-gang LI Yao Jose Marcato JUNIOR Jonathan LI Key Laboratory of Earth Exploration and Information Technology of Ministry of Education Chengdu University of TechnologyChengdu 610059China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do SulCampo Grande 79070-900Brazil Department of Geography and Environmental Management University of WaterlooWaterlooONN2L 3G1Canada

Accurate evaluation of landslide susceptibility is very important to ensure the safe operation of mountain *** Sichuan-Tibet Highway,which traverses the east of the Tibetan Plateau,frequently encounters natural *** studies generally use statistical methods to analyze the hazards along the Sichuan-Tibet *** this research,we present two road factors,namely aspect to road and road profile to increase the accuracy of landslide susceptibility mapping by considering the influence of landslide movement direction on ***,the aspect to road,which represents the impact of different landslide movement directions on the highway,was extracted by combining road direction with mountain ***,the road profile,which reflects the subgrade structure between the road and surrounding mountains,was extracted according to the terrain ***,the landslide susceptibility maps were produced based on the random forest(RF)method by using 473 landslides and 10 conditioning factors,including road factors(aspect to road,road profile)and primitive factors(slope,aspect,curvature,relief amplitude,peak ground acceleration,crustal movement velocity,faults,rainfall).The area under the receiver operating characteristic curve(AUC)and the Gini importance were used to evaluate the performance of proposed road *** AUC values on two groups that add road factors and only use primitive factors were 0.8517 and 0.8243,*** Gini importance indicated that road profile(0.123)and aspect to road(0.116)have a significant contribution to landslides compared with the primitive *** results of multi-collinearity analysis and frequency ratio confirmed the suitability of the road factors for predicting hazards along the highway.

关键词： Landslide susceptibility Spatial modeling Random forest Sichuan-Tibet Highway

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共掺杂稀土配合物Tb_(0.5)Eu_(0.5)(TTA)_3Dipy发光性质的研究

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光谱学与光谱分析 2007年第5期27卷 850-853页

作者：王勇赵谡玲吕玉光张福俊袁广才曹维良张敬畅王永生徐征北京交通大学光电子技术研究所发光与光信息技术教育部重点实验室北京化工大学现代催化研究所化工资源有效利用国家重点实验室佳木斯大学化学与药学院黑龙江佳木斯154007

以TTA为配体合成了新的共掺杂稀土配合物Tb0.5Eu0.5(TTA)3Dipy,通过与PVK的掺杂,分析了PVK和Tb0.5Eu0.5(TTA)3Dipy之间的能量传递过程,并且制备了以PVK∶Tb0.5Eu0.5(TTA)3Dipy为发光层的结构为ITO/PVK∶Tb0.5Eu0.5(TTA)3Dipy/PBD/Al的发光器件,通过改变两者之间的质量比,得到了较纯的Eu3+的红色发光。通过与PVK∶Eu(TTA)3混合体系的比较,发现Tb3+的引入,起到了能量传递桥梁的作用,提高了PVK到Eu3+的能量传递,从而抑制了PVK的发光。因此,通过引入适当的第二种金属离子,会增强另一稀土离子的发光,是作者提高稀土离子发光效率的一种有效的手段。

关键词：共掺杂稀土配合物能量传递电致发光(EL)

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Re–Os and Pb isotope features of pyrite in the Shihangli graphite deposit:implications of coal-generated graphite mineralization in central Hunan,South China

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Acta Geochimica 2023年第5期42卷 895-911页

作者： yong Zhang Dongsheng Ma Jian-Feng Gao Jiayong Pan Xupeng Lv Guoqi Liu Fujun Zhong Xiaotian Zhang Ying Liu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210046China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Yunnan Institute of Geological Survey Kunming 650032China

The coal metamorphism in Central Hunan pro-vides valuable information about hydrothermal activity and water/rock *** how to collect age data on hydrothermal fluid systems is necessary for understanding the history and genetic mechanisms of large-scale coal-generated graphite *** Shihangli graphite deposit,formed by significant siliceous hydrothermal alteration,is the most distinctive in Central ***–Os dating of pyrite from the Shihangli graphite deposit demonstrates that the coal-generated graphite mineraliza-tion age is-127.6±3.8 *** on in-situ mineral analysis,the hydrothermal pyrite in the Shihangli graphite deposit is mostly enriched in Sb,As,Au,W,Ag,Cu,Pb,and *** on the pyrite Re–Os isochron,the initial(^(187)Os/^(188)Os)values of pyrite were 1.03±0.24 and the Os(t)values varied from 571.8 to *** from the Shihangli graphite deposit comprises a Pb isotope composition similar to that of the Madiyi Formation bulk rock and stibnite from the Xikuangshan Sb *** on the Re–Os,Sr,S,and Pb isotopic compositions of sul-fides in the graphite and Sb deposits in Central Hunan,the Madiyi Formation was likely the primary source of ore-forming elements(Sb,Au,and As).The Re–Os and Pb isotope compositions of pyrite most likely reflect when large-scale fluid migration and coal-generated graphite mineralization occurred in Central Hunan.

关键词： Pyrite Re–Os Pb isotope Graphite Central Hunan

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Effect of loess for preventing contamination of acid mine drainage from coal waste

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 302-306页

作者： MA Bao-guo WANG Hui-yong GAO Ran LI Shu-li College of Water Resource and Hydroelectricity Hebei University of EngineeringHandan 056021China yongnian County Forestry Bureau ofHebei Yongnian 057150China

Acid mine drainage （AMD） that releases highly acidic, sulfate and metals-rich drainage is a serious environmental problem in coal mining areas in China. In order to study the effect of using loess for preventing AMD and controlling heavy metals contamination from coal waste, the column leaching tests were conducted. The results come from experiment data analyses show that the loess can effectively immobilize cadmium, copper, iron, lead and zinc in AMD from coal waste, increase pH value, and decrease Eh, EC, and 8024- concentrations of AMD from coal waste. The oxidation of sulfide in coal waste is prevented by addition of the loess, which favors the generation and adsorption of the alkalinity, the decrease of the population of Thiobacillusferrooxidans, the heavy metals immobilization by precipitation of sulfide and carbonate through biological sul- fate reduction inside the column, and the halt of the oxidation process of sulfide through iron coating on the surface of sulfide in coal waste. The loess can effectively prevent AMD and heavy metals contamination from coal waste in in-situ treatment systems.

关键词： acid coal waste acid mine drainage loess heavy metals contamination prevention

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Controlling the reaction kinetics in solution for uniform nanoshells of metal sul?des with sub-nanometer accuracy

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Science Bulletin 2019年第4期64卷 232-235页

作者： Shu-Yi Duan Zi-Xiao Wu Jun-Yu Piao De-Shan Bin yong-Gang Sun Xi-Jie Lin An-Min Cao Li-Jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and CAS Research/Education Center for Excellence in Molecular Sciences Institute of ChemistryChinese Academy of Sciences (CAS) University of Chinese Academy of Sciences (UCAS) Institute of Chemical Materials China Academy of Engineering Physics

Core-shell nanostructiKes have found broad potentials in a large variety of applications including catalysis, biomedicine, and energy conversion/storage devices [1,2]. The unique structural configuration endows the compos让e a capability to combine advantages of both core and shell materials, and deliver optimized properties through a rational design of the components [3]. Accordingly, numerous research efforts have been directed to the synthesis control of the coating materials to build desired nanoshells. Particularly, silica-based core-shell structures have witnessed enormous success benefiting from the flexible synthesis capability ensured by the Stober process, which provides favorable growth kinetics in solution to build precise configuration of silica nanoshells su让ed for their applications, for example, silica-based nanocapsules for controlled drug delivery [4].

关键词： Core-shell variety applications

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Detection of Multi-drug Resistant Acinetobacter Lwoffii Isolated from Soil of Mink Farm

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Biomedical and Environmental Sciences 2016年第7期29卷 521-523页

作者： SUN Na WEN yong Jun ZHANG Shu Qin ZHU Hong Wei GUO Li WANG Feng Xue CHEN Qiang MA Hong Xia CHENG Shi Peng State Key Laboratory for Molecular Biology of Special Economic Animals Institute of Special Economic Animals and PlantsChinese Academy of Agricultural Sciences CAASChangchun 130112JilinChina JL TEYAN Biological Technology Limited Liability Company Changchun 130000JilinChina Jilin Agricultural University Changchun 130000JilinChina

There were 4 Acinetobacter lwoffii obtained from soil *** antimicrobial susceptibility of the strains to 16 antimicrobial agents was investigated using K-B *** isolates showed the multi-drug *** presence of resistance genes and integrons was determined using *** aadA 1,aac（3＇）-IIc,aph（3＇）-VII,aac（6＇）-Ib,sul2,cat2,floR,and tet（K）genes were detected,respectively.

关键词： soil Detection of Multi-drug Resistant Acinetobacter Lwoffii Isolated from Soil of Mink Farm

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