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  1. Article ; Online: Halogen-Bond-Promoted Direct Cross-Coupling of Trifluoromethylated Alkyl Bromides with Coumarins/Quinolinones: Unraveling Trifluoromethyl Effects.

    Guo, Peng / Pu, Guoliang / Wang, Gairong / Zeng, Lin-Yuan / Li, Wei-Piao / Li, Xuefei / Zhou, Pan-Pan / He, Chun-Yang

    Organic letters

    2024  Volume 26, Issue 15, Page(s) 3097–3102

    Abstract: This study introduces a novel approach involving XB-mediated cross-coupling of α-trifluoromethylated alkyl bromides with coumarins and quinolinones under visible light irradiation. Both density functional theory (DFT) calculations and experimental ... ...

    Abstract This study introduces a novel approach involving XB-mediated cross-coupling of α-trifluoromethylated alkyl bromides with coumarins and quinolinones under visible light irradiation. Both density functional theory (DFT) calculations and experimental studies converge to suggest that the noncovalent interaction between alkyl bromides and DMAP, intensified by the α-trifluoromethyl group, plays a pivotal role in facilitating this chemoselective reaction.
    Language English
    Publishing date 2024-04-04
    Publishing country United States
    Document type Journal Article
    ISSN 1523-7052
    ISSN (online) 1523-7052
    DOI 10.1021/acs.orglett.4c00717
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Synthesis of Alkylated Polyfluorobenzenes through Decarboxylative Giese Addition of Aliphatic

    Zeng, Lin-Yuan / Qu, Pei-Zhen / Tao, Maoling / Pu, Guoliang / Jia, Jia / Wang, Pan / Shang, Maocai / Li, Xuefei / He, Chun-Yang

    The Journal of organic chemistry

    2023  Volume 88, Issue 19, Page(s) 14105–14114

    Abstract: Polyfluoroaromatic compounds play crucial roles in medicinal and material science. However, the synthesis of alkylated polyfluoroarenes has been relatively underdeveloped. In this study, we devised a novel decarboxylative coupling reaction between ... ...

    Abstract Polyfluoroaromatic compounds play crucial roles in medicinal and material science. However, the synthesis of alkylated polyfluoroarenes has been relatively underdeveloped. In this study, we devised a novel decarboxylative coupling reaction between aliphatic
    Language English
    Publishing date 2023-09-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.3c01672
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

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  3. Article: QRA-Grid: Quantitative Risk Analysis and Grid-based Pre-warning Model for Urban Natural Gas Pipeline

    Li, Shuang / Cheng, Chengqi / Pu, Guoliang / Chen, Bo

    ISPRS international journal of geo-information. 2019 Mar. 01, v. 8, no. 3

    2019  

    Abstract: With the increasing use and complexity of urban natural gas pipelines, the occurrence of accidents owing to leakage, fire, explosion, etc., has increased. Based on Quantitative Risk Analysis (QRA) models and Geographic Information System (GIS) technology, ...

    Abstract With the increasing use and complexity of urban natural gas pipelines, the occurrence of accidents owing to leakage, fire, explosion, etc., has increased. Based on Quantitative Risk Analysis (QRA) models and Geographic Information System (GIS) technology, we put forward a quantitative risk simulation model for urban natural gas pipeline, combining with a multi-level grid-based pre-warning model. We develop a simulation and pre-warning model named QRA-Grid, conducting fire and explosion risk assessment, presenting the risk by using a grid map. Experiments show that by using the proposed method, we can develop a fire and explosion accident pre-warning model for gas pipelines, and effectively predict areas in which accidents will happen. As a result, we can make a focused and forceful policy in areas which have some potential defects in advance, and even carry out urban planning once more, rebuilding it to prevent the risk.
    Keywords accidents ; geographic information systems ; grid maps ; issues and policy ; natural gas ; pipelines ; quantitative risk assessment ; simulation models ; urban planning
    Language English
    Dates of publication 2019-0301
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2655790-3
    ISSN 2220-9964
    ISSN 2220-9964
    DOI 10.3390/ijgi8030122
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: A Dynamic and Static Context-Aware Attention Network for Trajectory Prediction

    Yu, Jian / Zhou, Meng / Wang, Xin / Pu, Guoliang / Cheng, Chengqi / Chen, Bo

    ISPRS international journal of geo-information. 2021 May 16, v. 10, no. 5

    2021  

    Abstract: Forecasting the motion of surrounding vehicles is necessary for an autonomous driving system applied in complex traffic. Trajectory prediction helps vehicles make more sensible decisions, which provides vehicles with foresight. However, traditional ... ...

    Abstract Forecasting the motion of surrounding vehicles is necessary for an autonomous driving system applied in complex traffic. Trajectory prediction helps vehicles make more sensible decisions, which provides vehicles with foresight. However, traditional models consider the trajectory prediction as a simple sequence prediction task. The ignorance of inter-vehicle interaction and environment influence degrades these models in real-world datasets. To address this issue, we propose a novel Dynamic and Static Context-aware Attention Network named DSCAN in this paper. The DSCAN utilizes an attention mechanism to dynamically decide which surrounding vehicles are more important at the moment. We also equip the DSCAN with a constraint network to consider the static environment information. We conducted a series of experiments on a real-world dataset, and the experimental results demonstrated the effectiveness of our model. Moreover, the present study suggests that the attention mechanism and static constraints enhance the prediction results.
    Keywords data collection ; models ; prediction ; spatial data ; traffic
    Language English
    Dates of publication 2021-0516
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    Note NAL-AP-2-clean
    ZDB-ID 2655790-3
    ISSN 2220-9964
    ISSN 2220-9964
    DOI 10.3390/ijgi10050336
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: A Coarse-to-Fine Model for Geolocating Chinese Addresses

    Qian, Chunyao / Yi, Chao / Cheng, Chengqi / Pu, Guoliang / Liu, Jiashu

    ISPRS international journal of geo-information. 2020 Nov. 25, v. 9, no. 12

    2020  

    Abstract: Address geolocation aims to associate address texts to the geographic locations. In China, due to the increasing demand for LBS applications such as take-out services and express delivery, automatically geolocating the unstructured address information is ...

    Abstract Address geolocation aims to associate address texts to the geographic locations. In China, due to the increasing demand for LBS applications such as take-out services and express delivery, automatically geolocating the unstructured address information is the key issue that needs to be solved first. Recently, a few approaches have been proposed to automate the address geolocation by directly predicting geographic coordinates. However, such point-based methods ignore the hierarchy information in addresses which may cause poor geolocation performance. In this paper, we propose a hierarchical region-based approach for geolocating Chinese addresses. We model the address geolocation as a Sequence-to-Sequence (Seq2Seq) learning task, that is, the input sequence is a textual address, and the output sequence is a GeoSOT grid code which exactly represents multi-level regions covered by the address. A novel coarse-to-fine model, which combines BERT and LSTM, is designed to learn the task. The experimental results demonstrate that our model correctly understands the Chinese addresses and achieves the highest geolocation accuracy among all the baselines.
    Keywords accuracy ; geographical coordinates ; information ; learning ; models ; paper ; prediction ; spatial data ; China
    Language English
    Dates of publication 2020-1125
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    Note NAL-light
    ZDB-ID 2655790-3
    ISSN 2220-9964
    ISSN 2220-9964
    DOI 10.3390/ijgi9120698
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: GeoSOT-Based Spatiotemporal Index of Massive Trajectory Data

    Qian, Chunyao / Yi, Chao / Cheng, Chengqi / Pu, Guoliang / Wei, Xiaofeng / Zhang, Huangchuang

    ISPRS international journal of geo-information. 2019 June 18, v. 8, no. 6

    2019  

    Abstract: With the rapid development of global positioning technologies and the pervasiveness of intelligent mobile terminals, trajectory data have shown a sharp growth trend both in terms of data volume and coverage. In recent years, increasing numbers of LBS ( ... ...

    Abstract With the rapid development of global positioning technologies and the pervasiveness of intelligent mobile terminals, trajectory data have shown a sharp growth trend both in terms of data volume and coverage. In recent years, increasing numbers of LBS (location based service) applications have provided us with trajectory data services such as traffic flow statistics and user behavior pattern analyses. However, the storage and query efficiency of massive trajectory data are increasingly creating a bottleneck for these applications, especially for large-scale spatiotemporal query scenarios. To solve this problem, we propose a new spatiotemporal indexing method to improve the query efficiency of massive trajectory data. First, the method extends the GeoSOT spatial partitioning scheme to the time dimension and forms a global space–time subdivision scheme. Second, a novel multilevel spatiotemporal grid index, called the GeoSOT ST-index, was constructed to organize trajectory data hierarchically. Finally, a spatiotemporal range query processing method is proposed based on the index. We implement and evaluate the index in MongoDB. By comparing the range query efficiency and scalability of our index with those of the other two space–time composite indexes, we found that our approach improves query efficiency levels by approximately 40% and has better scalability under different data volumes.
    Keywords geospatial data processing ; global positioning systems ; space and time ; spatial data ; statistics ; traffic
    Language English
    Dates of publication 2019-0618
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2655790-3
    ISSN 2220-9964
    ISSN 2220-9964
    DOI 10.3390/ijgi8060284
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: Geospatial Information Service System Based on GeoSOT Grid & Encoding

    LI Shizhong / CHENG Chengqi / WANG Dong / PU Guoliang / CHEN Bo

    Acta Geodaetica et Cartographica Sinica, Vol 45, Iss S1, Pp 115-

    2016  Volume 120

    Abstract: With the rapid development of the space and earth observation technology, it is important to establish a multi-source, multi-scale and unified cross-platform reference for global data. In practice, the production and maintenance of geospatial data are ... ...

    Abstract With the rapid development of the space and earth observation technology, it is important to establish a multi-source, multi-scale and unified cross-platform reference for global data. In practice, the production and maintenance of geospatial data are scattered in different units, and the standard of the data grid varies between departments and systems. All these bring out the disunity of standards among different historical periods or orgnizations. Aiming at geospatial information security library for the national high resolution earth observation, there are some demands for global display, associated retrieval and template applications and other integrated services for geospatial data. Based on GeoSOT grid and encoding theory system, "geospatial information security library information of globally unified grid encoding management" data subdivision organization solutions have been proposed; system-level analyses, researches and designs have been carried out. The experimental results show that the data organization and management method based on GeoSOT can significantly improve the overall efficiency of the geospatial information security service system.
    Keywords geospatial information ; GeoSOT grid ; grid encoding ; multi-source data association ; multiscale data ; Mathematical geography. Cartography ; GA1-1776
    Subject code 020
    Language Chinese
    Publishing date 2016-12-01T00:00:00Z
    Publisher Surveying and Mapping Press
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

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