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Forecasting NDVI in multiple complex areas using neural network techniques combined feature engineering

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International Journal of Digital Earth 2020年第12期13卷 1733-1749页

作者： Changlu Cui Wen Zhang ZhiMing Hong lingkui meng School of Remote Sensing and Information Engineering Wuhan UniversityWuhanPeople’s Republic of China

NDVI(Normalized difference vegetation index)is a critical variable for monitoring climate change,studying ecological balance,and exploring the pattern of regional *** neural network models only consider image features in time series prediction,while historical data and its changes play an important role in time series *** this study,we proposed convolutional neural networks(CNN)combined feature engineering forecasting model(SF-CNN),which integrated both the advantages of image characteristics learned from CNN and statistic characteristics calculated by historical data related to the forecast period to improve the accuracy of NDVI predictions in the next 3 months with 30-day interval at multiple complex *** intuitively show the performance of SF-CNN,it was compared with CNN using the same *** mainly showed that(1)in terms of visual analysis,the texture,pattern,and structure of predicted NDVI using SF-CNN are similar to the observed NDVI,and SF-CNN exhibits strong generalization ability;(2)in terms of quantitative assessment,SF-CNN generally outperforms CNN,and it can improve the reliability and robustness for predicting NDVI through simple statistical characteristics while reducing the uncertainties;(3)SF-CNN can learn seasonal and sudden changes in four different and complex study areas with considerable accuracy and without extra data.

关键词： SF-CNN feature engineering CNN NDVI time series prediction

Exploring the Far Side of Glycosyl Sulfoxide Activation Process

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Chinese Journal of Chemistry 2023年第4期41卷 383-391页

作者： Wei Chen Pinru Wu Jing Zeng Jing Fang Zhiwen Liao Lei Cai Hao Wang lingkui meng Qian Wan Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyHuazhong University of Science and Technology13 Hangkong RoadWuhanHubei430030 China Wuhan Union Hospital of China Huazhong University of Science and Technology1277 Jiefang AvenueWuhanHubei430022 China

The discovery of Kahne glycosylation forwards a big step in the carbohydrate *** an extensive series of studies,the precise mechanism of this powerful glycosylation is still not fully *** address these 30-year puzzles,the far side of Kahne glycosylation is explored in this *** a series of control and tracking experiments,a number of important intermediates including glycosyl oxo-sulfonium ion and sulfenic anhydride(Crich's intermediate)are suggested to be responsible for the complex reaction *** also reveals that in addition to the conventional ionic glycosylation pathway,a novel free radical pathway is very likely to contribute to the various side-and *** study provides further understanding of Kahne glycosylation,and it also sheds light on how to improve the efficiency of sulfoxide-based glycosylation reactions.

关键词： Carbohydrates Kahne glycosylation Radicals Reaction mechanisms Reactive intermediates

Dehydrative Glycosylation Enabled by a Comproportionation Reaction of 2-Aryl-1,3-dithiane 1-Oxide

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Chinese Journal of Chemistry 2020年第1期38卷 43-49页

作者： Lei Cai Jing Zeng Ting Li Ying Xiao Xiang Ma Xiong Xiao Qin Zhang lingkui meng Qian Wan Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyHuazhong University of Science and Technology13 Hangkong RoadWuhanHubei 430030China Institute of Brain Research Huazhong University of Science and Technology13 Hangkong RoadWuhanHubei 430030China

Summaryof main observation and conclusion A new dehydrativeglycosylation reaction has been established by capitalizing on the compropor-tionation reaction of 2-aryl-1,3-dithiane 1-oxides promoted by triflic anhydride(Tf2O).By wedding the high potency of thiophilic promoter system with the step efficiency of dehydrative glycosylation,this reagentunderwent facile intermolecular oxothio acetalization with C1-hemiacetal donor to install a temporary leaving group,rendering a transient electrophilic center at the remote site to the anomeric *** sulfenyltriflate tethered at the ter-minus concomitantly activated the sulfide intramolecularly to afford the oxocarbenium ion,thereby facilitating the title *** from accom-modating broad range functional groups and inactive hemiacetal substrates,the present activation protocol also proved expedient for 1,3-diol *** importantly,this method further provided a fresh perspective for the application of sulfur chemistry to carbohydrate chemistry.

关键词： rendering thereby anhydride

Togni-ⅡReagent Mediated Selective Hydrotrifluoromethylation and Hydrothiolation of Alkenes

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Chinese Journal of Chemistry 2021年第12期39卷 3429-3434页

作者： Shuang Teng lingkui meng Bingbing Xu Guangsheng Tu Peng Wu Zhiwen Liao Yulin Tan Jian Guo Jing Zeng Qian Wan Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyHuazhong University of Science and Technology13 Hangkong RoadWuhanHubei 430030China Institute of Brain Research Huazhong University of Science and Technology13 Hangkong RoadWuhanHubei 430030China

Based on the redox reactions of Togni-Ⅱreagent and thiols,a thiol-tuned selective functionalization of unactivated olefins was *** combination with aryl thiols,stoichiometric amount of Togni-Ⅱreagent prompted a hydrotrifluoromethylation of alkenes,in which,aryl thiols played as reductant and hydrogen source;while by utilization of alkyl thiols,catalytic amount of Togni-Ⅱreagent initiated thiol-ene and thiol-yne *** reported applications are characterized by their operational simplicity and wide functional group tolerance.

关键词： Togni-Ⅱreagent Hydrotriflupromethylation Thiol-ene reaction Alkenes Radical reactions

Discriminating non-ylidic carbon-sulfur bond cleavages of sulfonium ylides for alkylation and arylation reactions

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Chinese Chemical Letters 2022年第1期33卷 288-292页

作者： Jing Fang Ting Li Xiang Ma Jiuchang Sun Lei Cai Qi Chen Zhiwen Liao lingkui meng Jing Zeng Qian Wan Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyHuazhong University of Science and TechnologyWuhan 430030China

A sulfonium ylide participated alkylation and arylation under transition-metal free conditions is *** disparate reaction pattern allowed the separate activation of non-ylidic S-alkyl and S-aryl *** acidic conditions,sulfonium ylides serve as alkyl cation precursors which facilitate the *** under alkaline conditions,cleavage of non-ylidic S-aryl bond produces O-arylated compounds *** robustness of the protocols were established by the excellent compatibility of wide variety of substrates including carbohydrates.

关键词： Sulfonium ylide Alkylation Arylation Non-ylidic C-S bond cleavage

Fuzzy Clustering Validity for Spatia Data

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Geo-Spatial Information Science 2008年第3期11卷 191-196页

作者： HU Chunchun meng lingkui SHI Wenzhong School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China.

The validity measurement of fuzzy clustering is a key problem. If clustering is formed, it needs a kind of machine to verify its validity. To make mining more accountable, comprehensible and with a usable spatial pattern, it is necessary to first detect whether the data set has a clustered structure or not before clustering. This paper discusses a detection method for clustered patterns and a fuzzy clustering algorithm, and studies the validity function of the result produced by fuzzy clustering based on two aspects, which reflect the un-certainty of classification during fuzzy partition and spatial location features of spatial data, and proposes a new validity function of fuzzy clustering for spatial data. The experimental result indicates that the new validity function can accurately measure the validity of the results of fuzzy clustering. Especially, for the result of fuzzy clustering of spatial data, it is robust and its classification result is better when compared to other indices.

关键词： fuzzy clustering spatial data validity uncertainty

复杂水体边界提取的改进正交T-Snake模型

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测绘学报 2015年第6期44卷 670-677页

作者：孟令奎吕琪菲武汉大学遥感信息工程学院湖北武汉430079

引入拓扑自适应动态轮廓(T-Snake)模型并进行了改进,设计了合适的能量函数,提出了目标内部岛状空洞引起的拓扑冲突的检测与处理机制,实现了包含河中岛的复杂河流边界的精确提取。针对模型初始轮廓需手动构造的缺点,利用影像分形维数最... 详细信息

引入拓扑自适应动态轮廓(T-Snake)模型并进行了改进,设计了合适的能量函数,提出了目标内部岛状空洞引起的拓扑冲突的检测与处理机制,实现了包含河中岛的复杂河流边界的精确提取。针对模型初始轮廓需手动构造的缺点,利用影像分形维数最小值获取水体内部区域并实现轮廓自动初始化。试验表明,该方法可有效提取水体深凹边界和含河中岛的河流边界,在精度和效率上优于传统Snake和GVF Snake模型。

关键词：拓扑自适应动态轮廓(T-Snake)模型河中岛初始轮廓分形维数边界提取

An Improved Hilbert Curve for Parallel Spatial Data Partitioning

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Geo-Spatial Information Science 2007年第4期10卷 282-286页

作者： meng lingkui HUANG Changqing ZHAO Chunyu LIN Zhiyong School of Remote Sensing and Information Engineering Wuhan University 129 Luoyu Road Wuhan 430079 China

A novel Hilbert-curve is introduced for parallel spatial data partitioning, with consideration of the huge-amount property of spatial information and the variable-length characteristic of vector data items. Based on the improved Hilbert curve, the algorithm can be designed to achieve almost-uniform spatial data partitioning among multiple disks in parallel spatial databases. Thus, the phenomenon of data imbalance can be significantly avoided and search and query efficiency can be enhanced.

关键词： parallel spatial database spatial data partitioning data imbalance Hilbert curve

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论硕士生专业实践与就业实习

研究生教育研究 2018年第2期 54-59页

作者：孟令奎武汉大学遥感信息工程学院武汉430079

提出硕士生应以就业为导向实施实践能力培养的模式,分析专业实践对提高研究生综合素质和就业竞争力的必要性。同时对于近年出现的以短期训练和临时计划为特征的就业实习现象进行深入分析,从性质、定位、时间、内容、形式、保障措施以及... 详细信息

提出硕士生应以就业为导向实施实践能力培养的模式,分析专业实践对提高研究生综合素质和就业竞争力的必要性。同时对于近年出现的以短期训练和临时计划为特征的就业实习现象进行深入分析,从性质、定位、时间、内容、形式、保障措施以及成效上与专业实践进行对比,建议弱化或限制就业实习、强化专业实践、丰富专业实践内容、规范专业实践环节,促使硕士研究生在专业实践中学习、应用、提高、成长。

关键词：硕士生专业实践就业实习综合能力