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Survey on vehicle map matching techniques

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CAAI Transactions on Intelligence Technology 2021年第1期6卷 55-71页

作者： Zhenfeng Huang Shaojie qiao Nan han Chang-an Yuan Xuejiang song Yueqiang Xiao School of Software Engineering Chengdu University of Information TechnologyChengduChina School of Management Chengdu University of Information TechnologyChengduChina School of Computer and Information Engineering Nanning Normal UniversityNanningChina Guangxi College of Education NanningChina Chengdu Tanmer Technology Co. LtdChengduChina

With the development of location‐based services and Big data technology,vehicle map matching techniques are growing rapidly,which is the fundamental techniques in the study of exploring global positioning system(GPS)*** pre‐processed GPS data can provide the guarantee of high‐quality data for the research of mining passenger’s points of interest and urban computing *** existing surveys mainly focus on map‐matching algorithms,but there are few descriptions on the key phases of the acquisition of sampling data,floating car and road data preprocessing in vehicle map matching *** address these limitations,the contribution of this survey on map matching techniques lies in the following aspects:(i)the background knowledge,function and system framework of vehicle map matching techniques;(ii)description of floating car data and road network structure to understand the detailed phase of map matching;(iii)data preprocessing rules,specific methodologies,and significance of floating car and road data;(iv)map matching algorithms are classified by the sampling frequency and data *** authors give the introduction of open‐source GPS sampling data sets,and the evaluation measurements of map‐matching approaches;(v)the suggestions on data preprocessing and map matching algorithms in the future work.

关键词： matching floating map

Engineering 3D approaches to model the dynamic microenvironments of cancer bone metastasis

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Bone Research 2018年第1期6卷 38-49页

作者： han qiao Tingting Tang Shanghai Key Laboratory of Orthopaedic Implants Department of Orthopaedic Surgery Shanghai Ninth People’s Hospital Shanghai Jiao Tong University School of Medicine

Cancer metastasis to bone is a three-dimensional(3D), multistep, dynamic process that requires the sequential involvement of three microenvironments, namely, the primary tumour microenvironment, the circulation microenvironment and the bone microenvironment. Engineered 3D approaches allow for a vivid recapitulation of in vivo cancerous microenvironments in vitro, in which the biological behaviours of cancer cells can be assessed under different metastatic conditions. Therefore, modelling bone metastasis microenvironments with 3 D cultures is imperative for advancing cancer research and anti-cancer treatment strategies. In this review, multicellular tumour spheroids and bioreactors, tissue engineering constructs and scaffolds, microfluidic systems and 3D bioprinting technology are discussed to explore the progression of the 3D engineering approaches used to model the three microenvironments of bone metastasis. We aim to provide new insights into cancer biology and advance the translation of new therapies for bone metastasis.

关键词： three-dimensional anti-cancer treatment modelling bone metastasis

Records of solar eclipse observations in ancient China

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1639-1645页

作者： han YanBen qiao QiYuan National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

Like ancient people at other places of the world, the ancient Chinese lived in awe of the Sun. As they felt solar eclipses extremely significant events, they closely observed the occurrence of solar eclipse. Ancient astronomers further realized very early that solar eclipses were one of the important astronomical phenomena to revise and improve the ancient calendar. Interestingly, ancient emperors regarded solar eclipses as warnings from heaven that might affect the stability of their throne. Consequently, observing and recording solar eclipses became official, which dated far back to ancient China when numerous relevant descriptions were recorded in historical books. These records contribute substantially to China as an ancient civilization, as well as to the research of the long-term variation of the rotation rate of the Earth during >2000 years before the 17th century. This paper briefly reviews the perception, observations and recording of solar eclipses by ancient Chinese astronomers.

关键词： solar eclipse ancient record ancient China Earth rotation

Observation of atmospheric methane in the Arctic Ocean up to 87° north

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Science China Earth Sciences 2017年第1期60卷 173-179页

作者： ZhanG Min qiao FangLi song ZhenYa The First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China Key Lab of Marine Science and Numerical Modeling State Oceanic Administration Qingdao 266061 China

Although the Arctic methane reservoir is large,the emission of methane from the Arctic Ocean into the atmosphere remains poorly *** ship-borne measurements of atmospheric methane near the surface ocean were carried out during two cruises to investigate methane emission from the Arctic Ocean up to the latitude of 87°***-day air mass back trajectories along the cruise tracks indicated that the surface Arctic Ocean could be a potentially important source of methane to the *** bursts in methane concentration occurred mainly along the ocean frontal area,suggesting that frontal upwelling in the upper layer of the Arctic Ocean might contribute to methane emissions into the atmosphere.

关键词： Methane The Arctic Ocean Frontal upwelling

On the accumulative contribution of CO_2 emission from China to global climate change

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Science China Earth Sciences 2016年第11期59卷 2202-2212页

作者： BAO Ying qiao FangLi song ZhenYa First Institute of Oceanography State Oceanic Administration Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology Key Lab of Marine Science and Numerical Modeling State Oceanic Administration

A study of the contribution to global climate change from China's CO_2 emission is conducted using the FIO-ESM v1.0 climate model. A series of sensitivity experiments are performed to identify two kinds of contributions to global climate change of China's CO_2 emission due to fossil fuel combustion: one is the pure contribution which is the historical climate response from the sensitivity experiment forced only by China's CO_2 emission, the other is the accumulative contribution which is proposed in this research and defined as the difference of historical climate responses between the experiments forced by all countries' CO_2 emission and other countries' CO_2 emission excluding China. The pure contribution approach considers the total CO_2 discharged by China, while the accumulative contribution approach considers not only the discharge amount of China but also the discharge order of China and other countries. The latter is a more realistic approach to quantify the contribution of CO_2 emission to the historical change of atmospheric CO_2 concentration, surface air temperature(SAT), sea surface temperature(SST) and sea ice coverage in the Arctic. Model results show that from the accumulative perspective, the ratio of the contribution of CO_2 emission from China for the increase of atmospheric CO_2 concentration, SAT and SST, and the decrease of the sea ice coverage in the Arctic to that from all other countries excluding China varies from 8% to 92%, 5% to 95%, 9% to91% and 18% to 82%, respectively. Here we take the contribution of China's CO_2 emission as an example, the contribution of CO_2 emission from any other country or area can be evaluated by the same approach.

关键词： Accumulative contribution Pure contribution Climate model CO_2 emission

Chromospheric oscillations observed with BBSO and TRACE

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1718-1722页

作者： song qiao ZhanG Jun Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China

We examine chromospheric oscillations in both a coronal hole (CH) and a quiet Sun (QS) region, by employing Transition Region and Coronal Explorer (TRACE) and Big Bear Solar Observatory (BBSO) data on September 14 and 16, 2004. For the CH, the average oscillation periods of network magnetic field and non-magnetic field (NMF) regions are 257 and 222 s, respectively, and the average period of network field is longer than that of NMF region by 15.8%. In the QS, the average oscillation period is the 225 s for network field and 212 s for the NMF region. The average period of the network field is also longer than that of the NMF region by 6.1%. For the network region, we find that the average period in the CH is longer than that in the QS by 14.2%. This difference between CH and QS is possibly caused by different magnetic configurations i.e. the open magnetic field in the CH and the close field in the QS.

关键词： chromosphere oscillations UV radiation magnetic fields quiet Sun coronal hole

Friendship prediction model based on factor graphs integrating geographical location

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CAAI Transactions on Intelligence Technology 2020年第3期5卷 193-199页

作者： Liang Chen Shaojie qiao Nan han Chang-an Yuan Xuejiang song Ping Huang Yueqiang Xiao School of Software Engineering Chengdu University of Information TechnologyChengdu 610225People’s Republic of China School of Management Chengdu University of Information TechnologyChengdu 610103People’s Republic of China School of Computer and Information Engineering Nanning Normal UniversityNanning Guangxi 530299People’s Republic of China Guangxi College of Education Nanning Guangxi 530023People’s Republic of China Chengdu Tanmer Technology Co. LtdChengdu 610000People’s Republic of China

With the development of network services and location-based systems,many mobile applications begin to use users’geographical location to provide better *** terms of social networks,geographical location is actively shared by *** some applications with recommendation services,before the geographical location recommendation is provided,the authors have to obtain user’s *** kind of social network integrated with geographical location information is called location-based social networks(abbreviate for LBSNs).In the LBSN,each user has location information when he or she checked in hotels or feature *** on this information,they can identify user’s trajectory of movement behaviour and activity *** general,if there is friendship between two users,their trajectories in reality are likely to be *** this study,according to user’s geographical location information over a period of time,they explore whether there exists friendly relationship between two users based on trajectory similarity and the structure theory of *** particular,they propose a new factor function and a factor graph model based on user’s geographical location to predict the friendship between two users in the real LBSN.

关键词： LBS services prediction

Numerical investigation of the influence of vortex generator on propeller cavitation and hull pressure fluctuation by DDES

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Journal of Hydrodynamics 2022年第3期34卷 444-450页

作者： Yun Long han-qiao han Bin Ji Xin-ping Long Wuhan Second Ship Design and Research Institute Wuhan430064China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China

In this study,the delayed detached eddy simulation(DDES)is coupled with a homogenous cavitation model to simulate the cavitating turbulent flow around a propeller behind a full body ship with special emphasis on the influence of the vortex generator(VG)on the propeller cavitation and the hull pressure *** small calculation uncertainty as evaluated by the DDES verification and validation(V&V)method indicates that the present simulation can accurately reproduce the propeller performance and cavitation,and the predicted hull pressure fluctuation is in a fairly good agreement with the available experimental *** mechanism is explored through the current numerical results how the VG affects the local velocity distribution,along with the influences of the VG on the propeller cavitation and the hull pressure *** is shown that the streamwise vortex is induced by the VG near the hull boundary *** very low velocity region in the hull wake is reduced due to the effect of the streamwise ***,the propeller cavitation develops more mildly and the hull pressure fluctuation decreases due to the influence of the VG.

关键词： Propeller cavitation delayed detached eddy simulation(DDES) vortex generator(VG) streamwise vortex

Geochemical Characteristics of Eolian Deposits on the Eastern Margin of the Tibetan Plateau and Implications for Provenance

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 963-973页

作者： QI Lin qiao Yan-song School of Earth Sciences and Resources China University of Geosciences Institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Neotectonic Movement and Geohazard

Eolian dust deposition is intimately related to atmospheric circulation and environmental setting of the source region,and therefore is an invaluable tool for studying the evolutionary history of atmospheric circulation patterns and paleoclimatic *** the provenance of any eolian deposit is crucial not only for reconstructing the paleoenvironmental history of the dust source region,but also for understanding the paleoclimatic significance of various *** and paleosol samples from the Garze region on the eastern margin of the Tibetan Plateau （TP） were analyzed for their elemental （major and trace elements） and isotopic （Sm-Nd） geochemistry and compared with those of Northern Chinese （NC） loess formed at the same *** results show that the geochemical compositions of the Garze loess and paleosol samples are similar to those eolian deposits on the Chinese Loess Plateau （CLP）,and also resemble the average *** indicates that the eolian deposits on the eastern margin of the TP were derived from well-mixed sedimentary protoliths that had undergone numerous upper crustal recycling processes,just as with the CLP loess ***,compared with NC loess,the Garze samples have higher ∑REE,Li,Rb,Zr,Cs,Hf and Bi concentrations,higher TiO2/Al2O3,Hf/Nb,La/Nb,Th/Nb and lower K2O/TiO2,Zr/Hf,Ba/Rb *** the Sm-Nd isotopic geochemistry,εNd（0） and 147Sm/144Nd values of Garze loess and paleosol samples are clearly lower than the NC *** higher Bi,Zr and Hf concentrations are relevant to the widely distributed acid-magmatic rocks in this region,whereas the higher contents of Li,Cs,Rb are attributed to the high background values of the *** geochemical characteristics of the Garze loess and paleosol samples further prove that the local glacial and other Quaternary detrital sediments are predominantly the contributors for the eolian deposits on the eastern margin of the *** element concentrations and their ratios in the Garze loess and

关键词： Quaternary eolian sedimentology geochemistry provenance Tibetan paleoclimate,Sichuan province