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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data 被引量:2
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作者 Yunping Chen Jie Hu +6 位作者 Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1164-1178,共15页
Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while r... Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities. 展开更多
关键词 ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data
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A systematic study of Erzhu Erchen decoction against damp-heat internalized type 2 diabetes based on data mining and experimental verification
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作者 Peng-Yu Wang Jian-Fen Shen +4 位作者 Shuo Zhang Qing Lan Guan-Di Ma Tong Wang You-Zhi Zhang 《Traditional Medicine Research》 2024年第2期27-41,共15页
Background:Erzhu Erchen decoction(EZECD),which is based on Erchen decoction and enhanced with Atractylodes lancea and Atractylodes macrocephala,is widely used for the treatment of dampness and heat(The clinical manife... Background:Erzhu Erchen decoction(EZECD),which is based on Erchen decoction and enhanced with Atractylodes lancea and Atractylodes macrocephala,is widely used for the treatment of dampness and heat(The clinical manifestations of Western medicine include thirst,inability to drink more,diarrhea,yellow urine,red tongue,et al.)internalized disease.Nevertheless,the mechanism of EZECD on damp-heat internalized Type 2 diabetes(T2D)remains unknown.We employed data mining,pharmacology databases and experimental verification to study how EZECD treats damp-heat internalized T2D.Methods:The main compounds or genes of EZECD and damp-heat internalized T2D were obtained from the pharmacology databases.Succeeding,the overlapped targets of EZECD and damp-heat internalized T2D were performed by the Gene Ontology,kyoto encyclopedia of genes and genomes analysis.And the compound-disease targets-pathway network were constructed to obtain the hub compound.Moreover,the hub genes and core related pathways were mined with weighted gene co-expression network analysis based on Gene Expression Omnibus database,the capability of hub compound and genes was valid in AutoDock 1.5.7.Furthermore,and violin plot and gene set enrichment analysis were performed to explore the role of hub genes in damp-heat internalized T2D.Finally,the interactions of hub compound and genes were explored using Comparative Toxicogenomics Database and quantitative polymerase chain reaction.Results:First,herb-compounds-genes-disease network illustrated that the hub compound of EZECD for damp-heat internalized T2D could be quercetin.Consistently,the hub genes were CASP8,CCL2,and AHR according to weighted gene co-expression network analysis.Molecular docking showed that quercetin could bind with the hub genes.Further,gene set enrichment analysis and Gene Ontology represented that CASP8,or CCL2,is negatively involved in insulin secretion response to the TNF or lipopolysaccharide process,and AHR or CCL2 positively regulated lipid and atherosclerosis,and/or including NOD-like receptor signaling pathway,and TNF signaling pathway.Ultimately,the quantitative polymerase chain reaction and western blotting analysis showed that quercetin could down-regulated the mRNA and protein experssion of CASP8,CCL2,and AHR.It was consistent with the results in Comparative Toxicogenomics Database databases.Conclusion:These results demonstrated quercetin could inhibit the expression of CASP8,CCL2,AHR in damp-heat internalized T2D,which improves insulin secretion and inhibits lipid and atherosclerosis,as well as/or including NOD-like receptor signaling pathway,and TNF signaling pathway,suggesting that EZECD may be more effective to treat damp-heat internalized T2D. 展开更多
关键词 data mining damp-heat internalized type 2 diabetes Erzhu Erchen decoction network pharmacology BIOINFORMATICS
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Structural Setting of the South-West Cameroon Using Satellite Potential Field Derived from SGG-UGM-2 Gravity Data
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作者 Jean Aimé Mono 《Journal of Geoscience and Environment Protection》 2024年第8期43-61,共19页
This study aims to improve knowledge of the structure of southwest Cameroon based on the analysis and interpretation of gravity data derived from the SGG-UGM-2 model. A residual anomaly map was first calculated from t... This study aims to improve knowledge of the structure of southwest Cameroon based on the analysis and interpretation of gravity data derived from the SGG-UGM-2 model. A residual anomaly map was first calculated from the Bouguer anomaly map, which is strongly affected by a regional gradient. The residual anomaly map generated provides information on the variation in subsurface density, but does not provide sufficient information, hence the interest in using filtering with the aim of highlighting the structures affecting the area of south-west Cameroon. Three interpretation methods were used: vertical gradient, horizontal gradient coupled with upward continuation and Euler deconvolution. The application of these treatments enabled us to map a large number of gravimetric lineaments materializing density discontinuities. These lineaments are organized along main preferential directions: NW-SE, NNE-SSW, ENE-WSW and secondary directions: NNW-SSE, NE-SW, NS and E-W. Euler solutions indicate depths of up to 7337 m. Thanks to the results of this research, significant information has been acquired, contributing to a deeper understanding of the structural composition of the study area. The resulting structural map vividly illustrates the major tectonic events that shaped the geological framework of the study area. It also serves as a guide for prospecting subsurface resources (water and hydrocarbons). . 展开更多
关键词 SGG-UGM-2 Model Horizontal Gradient Bouguer Anomalies Potential Field data
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基于OCO-2卫星数据的中国CO_(2)浓度时空变化特征
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作者 杨梅焕 邓彦昊 +2 位作者 王涛 姚明昊 赵滢滢 《遥感信息》 CSCD 北大核心 2024年第2期52-60,共9页
大气CO_(2)浓度增加引起的全球变暖问题是国内外学者关注的热点议题,但对CO_(2)的监测一直存在较多的不确定性。利用2015—2022年OCO-2卫星观测的CO_(2)柱浓度混合比数据(XCO_(2)),基于克里金插值和标准差椭圆等方法,分析了中国CO_(2)... 大气CO_(2)浓度增加引起的全球变暖问题是国内外学者关注的热点议题,但对CO_(2)的监测一直存在较多的不确定性。利用2015—2022年OCO-2卫星观测的CO_(2)柱浓度混合比数据(XCO_(2)),基于克里金插值和标准差椭圆等方法,分析了中国CO_(2)浓度时空分布与变化特征,有以下3个结论。1)基于OCO-2卫星数据的XCO_(2)数据集精度较高,与地面监测站(瓦里关站、鹿林站)观测结果的均方根误差仅为1.75 ppm和1.58 ppm,相关系数分别为0.91和0.96。2)年际上,2015—2022年中国年均XCO_(2)由399.52 ppm增至417.64 ppm,年均增速为2.56 ppm/a,高于过去10年全球CO_(2)浓度平均增速(2.06 ppm/a),但在2019年之后XCO_(2)增速呈下降趋势。季节上,XCO_(2)具有明显的季节变化特征,春季XCO_(2)最高,夏季最低。3)空间分布上,XCO_(2)表现出东部高,西部、东北地区低的空间分布特征。XCO_(2)浓度高值区域集中在京津冀和长三角等城市群。中国东北、西南地区XCO_(2)增速较快,高于华东、华南等经济发达地区。 展开更多
关键词 遥感数据反演 OCO-2 XCO_(2) 时空分析
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早发型2型糖尿病患者子女颈动脉全息血管硬度及影响因素分析
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作者 陈纪昀 郭艳艳 +3 位作者 袁建军 张喜君 吴铭 朱好辉 《中国医学影像学杂志》 CSCD 北大核心 2024年第9期897-902,共6页
目的评估早发型2型糖尿病患者子女颈动脉弹性功能,并分析影响其弹性的因素。资料与方法前瞻性分析2020年10月—2021年8月河南省人民医院2型糖尿病患者子女63例,根据其父母糖尿病发病年龄(<40岁为早发型,≥40岁为晚发型)分为父母早发... 目的评估早发型2型糖尿病患者子女颈动脉弹性功能,并分析影响其弹性的因素。资料与方法前瞻性分析2020年10月—2021年8月河南省人民医院2型糖尿病患者子女63例,根据其父母糖尿病发病年龄(<40岁为早发型,≥40岁为晚发型)分为父母早发糖尿病子女组(早发组,32例)和父母晚发糖尿病子女组(晚发组,31例)。同期选择32例年龄、性别及体重指数相匹配的健康志愿者作为对照组。应用全息血管内-中膜厚度测量和全息血管硬度分析技术测量受试者颈总动脉内-中膜厚度、血管壁位移、血管收缩期管径、硬度指数和脉搏波传导速度,比较上述参数的组间差异。结果早发组颈动脉内-中膜厚度、脉搏波传导速度、硬度指数高于晚发组及对照组(t=0.054~1.228,P均<0.05),血管壁位移低于晚发组及对照组(t=0.048、0.109,P<0.05)。结论2型糖尿病患者子女颈动脉僵硬度明显高于正常对照组,且早发组的颈动脉弹性下降较晚发组更明显。 展开更多
关键词 糖尿病 2 超声检查 颈动脉弹性 颈动脉内膜中层厚度 全息血管硬度分析技术 早发型 子女
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Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction 被引量:1
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作者 Yangtian Liu Xiaopeng Yan +2 位作者 Qiang Liu Tai An Jian Dai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期328-338,共11页
The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-n... The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio fuzes.To solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is proposed.First,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)signal.Then,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for classification.The DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical algorithms.The trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs. 展开更多
关键词 Automatic modulation recognition Adaptive denoising data rearrangement and the 2D FFT(DR2D) Radio fuze
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A Novel Computationally Efficient Approach to Identify Visually Interpretable Medical Conditions from 2D Skeletal Data
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作者 Praveen Jesudhas T.Raghuveera 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期2995-3015,共21页
Timely identification and treatment of medical conditions could facilitate faster recovery and better health.Existing systems address this issue using custom-built sensors,which are invasive and difficult to generaliz... Timely identification and treatment of medical conditions could facilitate faster recovery and better health.Existing systems address this issue using custom-built sensors,which are invasive and difficult to generalize.A low-complexity scalable process is proposed to detect and identify medical conditions from 2D skeletal movements on video feed data.Minimal set of features relevant to distinguish medical conditions:AMF,PVF and GDF are derived from skeletal data on sampled frames across the entire action.The AMF(angular motion features)are derived to capture the angular motion of limbs during a specific action.The relative position of joints is represented by PVF(positional variation features).GDF(global displacement features)identifies the direction of overall skeletal movement.The discriminative capability of these features is illustrated by their variance across time for different actions.The classification of medical conditions is approached in two stages.In the first stage,a low-complexity binary LSTM classifier is trained to distinguish visual medical conditions from general human actions.As part of stage 2,a multi-class LSTM classifier is trained to identify the exact medical condition from a given set of visually interpretable medical conditions.The proposed features are extracted from the 2D skeletal data of NTU RGB+D and then used to train the binary and multi-class LSTM classifiers.The binary and multi-class classifiers observed average F1 scores of 77%and 73%,respectively,while the overall system produced an average F1 score of 69%and a weighted average F1 score of 80%.The multi-class classifier is found to utilize 10 to 100 times fewer parameters than existing 2D CNN-based models while producing similar levels of accuracy. 展开更多
关键词 Action recognition 2D skeletal data medical condition computer vision deep learning
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基于WorldView-2高分影像信息增强及提取在卡而却卡地区遥感调查中的应用
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作者 魏本赞 张策 +2 位作者 张恩 卢辉雄 汪冰 《世界核地质科学》 CAS 2024年第5期1013-1022,共10页
为进一步探讨WorldView-2高分遥感数据在遥感调查中的应用效果,笔者选择青海卡而却卡地区进行图像信息增强及信息提取方法研究。在分析研究区内不同岩性的光谱曲线特征的基础上,针对遥感解译中目视解译效果不好、图像模糊和对比度不够... 为进一步探讨WorldView-2高分遥感数据在遥感调查中的应用效果,笔者选择青海卡而却卡地区进行图像信息增强及信息提取方法研究。在分析研究区内不同岩性的光谱曲线特征的基础上,针对遥感解译中目视解译效果不好、图像模糊和对比度不够等问题,提出一系列图像增强处理的方法,这些方法显著增强了岩性、构造的识别效果,可以更好地辅助高分遥感解译工作。同时,通过基于纹理和光谱信息的影像分类方法对大理岩、岩浆岩信息提取研究,可以较准确地圈定大理岩、岩浆岩岩性界线,并通过与现有地质矿产资料进行对比,该方法形成的岩性-构造解译图反映的岩性、构造等信息更加详细、丰富。 展开更多
关键词 WorldView-2数据 光谱特征 图像增强 信息提取 卡而却卡地区
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基于数据挖掘探讨张传志主任医师治疗2型糖尿病的用药规律
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作者 南瑞雪 何德英 +1 位作者 王毅刚 任毅 《临床合理用药杂志》 2024年第28期12-16,共5页
目的基于数据挖掘探讨张传志主任医师治疗2型糖尿病的用药规律。方法收集2021年10月—2022年10月于重庆市中医院门诊治疗的2型糖尿病患者151例临床资料。使用Excel 2021、SPSS 22.0、SPSS Modeler 18.0软件对药物的频次、性味归经、强... 目的基于数据挖掘探讨张传志主任医师治疗2型糖尿病的用药规律。方法收集2021年10月—2022年10月于重庆市中医院门诊治疗的2型糖尿病患者151例临床资料。使用Excel 2021、SPSS 22.0、SPSS Modeler 18.0软件对药物的频次、性味归经、强关联药物等进行分析。结果151首处方共涉及177味中药,排名前10位的中药分别是葛根、炒谷芽、丹参、黄芪、苍术、炒麦芽、山药、炒白扁豆、红曲、茯苓,药性以温、寒、平性最多,药味以甘、苦为主,归经以脾、胃、肺为主,关联频次>80次的药物有15组,聚类分析获得核心药物组合4组。结论张传志主任医师治疗2型糖尿病以健脾祛湿为主,兼补肺滋肾,同时活血化瘀。 展开更多
关键词 2型糖尿病 数据挖掘 用药规律 经验总结
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Exploring medication rules in Chinese randomized controlled trials of type 2 diabetes based on data mining technology
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作者 Zhi-Li Dou Hao-Nan Sun +6 位作者 Yu-Nan Zhang Lei Zhao Zhe Huang Shu-Jing Xu Yi-Xing Liu Dong-Ran Han Jin-Zhu Jia 《Medical Data Mining》 2023年第4期46-57,共12页
Background:To systematically summarize and categorize the Chinese herbal medicine in the domestic traditional Chinese medicine(TCM)literature on type 2 diabetes mellitus(T2DM),in this paper,we mine traditional Chinese... Background:To systematically summarize and categorize the Chinese herbal medicine in the domestic traditional Chinese medicine(TCM)literature on type 2 diabetes mellitus(T2DM),in this paper,we mine traditional Chinese medicine data for relationships and provide for future practitioners and researchers.Methods:Taking randomized controlled trials on the treatment of T2DM in TCM as the research theme,we searched for full-text literature in three major clinical databases,including CNKI,Wan Fang,and VIP,published between 1990 and 2020.We then conducted frequency statistics,cluster analysis,association rules extraction,and principal component analysis based on a corpus of medical academic words extracted from 1116 research articles.Results:The most frequently used is Astragali Radix,and the most commonly used two-herb combination in T2DM treatment consisted of Coptidis Rhizoma and Moutan Cortex.Moutan Cortex,Alismatis Rhizoma,and Dioscoreae Rhizoma were the most frequently used three-herb combination.We found a“lung”and“liver”and“kidney”model and confirmed the value of classical meridian tropism theory and pattern identification.The treatment is mainly to fill deficiency and clear heat and consider water infiltration,dampness,blood circulation,and silt.Conclusion:This study provides an in-depth perspective on the TCM medication rules for T2DM and offers practitioners and researchers valuable information about the current status and frontier trends of TCM research on T2DM in terms of diagnosis and treatment. 展开更多
关键词 type 2 diabetes mellitus traditional Chinese medicine syndromes Chinese herbal medicine data mining
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基于数据挖掘杨晓晖教授治疗2型糖尿病用药规律分析
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作者 袁如月 杨玉涵 +2 位作者 黄举凯 张力 杨晓晖 《辽宁中医药大学学报》 CAS 2024年第3期42-46,共5页
目的 基于中医传承计算平台,对杨晓晖教授治疗2型糖尿病患者的用药规律进行分析。方法 收集整理了杨晓晖教授2019—2022年门诊诊治的2型糖尿病患者医案,按照纳入、排除标准进行筛选及数据标准化,使用中医传承计算平台V3.0中频次分析、... 目的 基于中医传承计算平台,对杨晓晖教授治疗2型糖尿病患者的用药规律进行分析。方法 收集整理了杨晓晖教授2019—2022年门诊诊治的2型糖尿病患者医案,按照纳入、排除标准进行筛选及数据标准化,使用中医传承计算平台V3.0中频次分析、关联规则分析、聚类分析等功能进行数据挖掘。结果 研究共纳入173例患者,553个门诊医案,使用频率最高的前10味中药分别为黄连、赤芍、柴胡、蝉蜕、百合、牛膝、蒲黄、女贞子、知母、佛手。常用药以清热类、补虚类、解表类、活血化瘀类、化痰止咳平喘类药物为主。药性以寒性居多,药味以苦味为主,归经主入肝经,其次为肺经及脾经。关联规则分析结果显示,“黄连-赤芍”“赤芍-柴胡”“黄连-蝉蜕”等为高频药物组合模式,聚类分析得到3组核心处方,结合杨晓晖教授临床经验,认为核心药串为“黄连、赤芍、柴胡”。结论 杨晓晖教授治疗2型糖尿病重视气血在发病中的重要作用。用药多入肝、脾、肺三经,意在通调气机,补益脏腑虚损;寒温并用,以取清热不伤正、补虚不助邪之效。治疗紧抓“阴虚燥热”的基本病机,气血同调,补益脏腑虚损,兼顾气郁、痰湿、瘀血等实邪的祛除。 展开更多
关键词 数据挖掘 中医传承计算平台 用药规律 2型糖尿病
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基于深度置信网络的2型糖尿病微血管并发症预测
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作者 李瑞瑶 许婧怡 +4 位作者 戴浩宇 孙慧文 鲍瀛 华履春 吴天星 《医学信息学杂志》 CAS 2024年第7期68-73,共6页
目的/意义基于真实世界数据构建预测模型,实现对2型糖尿病微血管病变的预测和早期筛查。方法/过程以南京鼓楼医院10年间真实世界数据为资料,将检验检查结果、病历文书等纳入考量,构建基于粒子群算法优化深度置信网络的2型糖尿病微血管... 目的/意义基于真实世界数据构建预测模型,实现对2型糖尿病微血管病变的预测和早期筛查。方法/过程以南京鼓楼医院10年间真实世界数据为资料,将检验检查结果、病历文书等纳入考量,构建基于粒子群算法优化深度置信网络的2型糖尿病微血管并发症预测模型。结果/结论该模型能够预测2型糖尿病微血管并发症,性能优于随机森林、支持向量机基准模型,为真实世界数据疾病预测模型研究提供借鉴。 展开更多
关键词 2型糖尿病 微血管并发症 疾病预测模型 临床数据处理 真实世界数据
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固利相兼治疗2型糖尿病肾病用药规律
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作者 黄博臻 周美娇 +1 位作者 蓝宇洋 吴深涛 《中南药学》 CAS 2024年第9期2501-2507,共7页
目的深入探析吴深涛教授“固利相兼”治疗2型糖尿病肾病的用药规律。方法收集2016年1月至2022年12月吴深涛教授诊治2型糖尿病肾病医案,建立相关数据库,运用Microsoft Office Excel 2021、SPSS Modeler 18.0和SPSS Statistics 26.0分别... 目的深入探析吴深涛教授“固利相兼”治疗2型糖尿病肾病的用药规律。方法收集2016年1月至2022年12月吴深涛教授诊治2型糖尿病肾病医案,建立相关数据库,运用Microsoft Office Excel 2021、SPSS Modeler 18.0和SPSS Statistics 26.0分别对处方药物进行频数统计、关联分析和聚类分析。结果共纳入832首中药处方,涉及药物228味,使用频次共计13288次。单味药物使用频率前3名的中药分别为黄芪、茯苓、石莲子。四气以寒、温、平为主,五味以甘、苦、辛为主,归经以肝、肺、脾为主,功效分类以补虚药、清热药、利水渗湿药、活血化瘀药为主。中医证型分布中,虚证以肾虚证为主,实证以浊毒内蕴证为主。高频药物关联分析得出药物组合9个,高频药物聚类分析得出核心组方3个。结论本研究借助数据挖掘技术,全面阐释了吴深涛教授“固利相兼”辨治2型糖尿病肾病的深刻内涵,即“固取精微”并非单纯地使用收涩药,更应健脾益肾以助其统摄之力。“泄利浊毒”之含义不可囿于化浊解毒,更应辨“浊毒”所处病位之异,或“清泄”,或“通利”,因势利导,予“浊毒”以出路。 展开更多
关键词 2型糖尿病肾病 数据挖掘 用药规律
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2018-2022年青海省主要湖泊蓄水量时空变化数据集
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作者 张怀文 曹引 +3 位作者 赵红莉 蒋云钟 严登明 赵慧子 《中国科学数据(中英文网络版)》 CSCD 2024年第1期314-327,共14页
青海省是中国西北部重要的生态功能区,水资源总量丰富,但时空分布极不均匀,且由于气候、地理环境等因素的影响,大部分湖泊长期缺乏监测。而湖泊作为地表水水资源的重要载体,是研究气候变化和人类活动对水循环过程影响的重要指示器。国... 青海省是中国西北部重要的生态功能区,水资源总量丰富,但时空分布极不均匀,且由于气候、地理环境等因素的影响,大部分湖泊长期缺乏监测。而湖泊作为地表水水资源的重要载体,是研究气候变化和人类活动对水循环过程影响的重要指示器。国产高分一号、六号卫星宽幅相机空间分辨率为16 m,组网运行可实现2天重复观测,可以高频次获取地表水体面积;ICESat-2激光测高数据具备厘米级的测高精度,可以获取高精度的地表水体测高水位。本数据集基于GF-1/6WFV水体面积和ICESat-2测高水位构建青海省湖泊蓄水量遥感监测模型,通过遥感手段对青海省湖泊蓄水量进行时空变化监测。经验证,本数据集中湖泊蓄变量监测精度总体优于93%,满足湖泊蓄水量时空变化遥感监测需求。本数据集在时间尺度上涵盖2018-2022年,共计60期月度监测结果;空间尺度上覆盖了青海省面积大于30 km^(2)的33个湖泊,主要集中分布在青海省西部、北部、东南部,可为青海省湖泊、水文与气候变化过程监测、水资源动态评价、优化水资源管理与调度提供基础数据支撑。 展开更多
关键词 湖泊蓄水量 GF-1/6 WFV ICESat-2 青海省 2018-2022
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An Innovative K-Anonymity Privacy-Preserving Algorithm to Improve Data Availability in the Context of Big Data
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作者 Linlin Yuan Tiantian Zhang +2 位作者 Yuling Chen Yuxiang Yang Huang Li 《Computers, Materials & Continua》 SCIE EI 2024年第4期1561-1579,共19页
The development of technologies such as big data and blockchain has brought convenience to life,but at the same time,privacy and security issues are becoming more and more prominent.The K-anonymity algorithm is an eff... The development of technologies such as big data and blockchain has brought convenience to life,but at the same time,privacy and security issues are becoming more and more prominent.The K-anonymity algorithm is an effective and low computational complexity privacy-preserving algorithm that can safeguard users’privacy by anonymizing big data.However,the algorithm currently suffers from the problem of focusing only on improving user privacy while ignoring data availability.In addition,ignoring the impact of quasi-identified attributes on sensitive attributes causes the usability of the processed data on statistical analysis to be reduced.Based on this,we propose a new K-anonymity algorithm to solve the privacy security problem in the context of big data,while guaranteeing improved data usability.Specifically,we construct a new information loss function based on the information quantity theory.Considering that different quasi-identification attributes have different impacts on sensitive attributes,we set weights for each quasi-identification attribute when designing the information loss function.In addition,to reduce information loss,we improve K-anonymity in two ways.First,we make the loss of information smaller than in the original table while guaranteeing privacy based on common artificial intelligence algorithms,i.e.,greedy algorithm and 2-means clustering algorithm.In addition,we improve the 2-means clustering algorithm by designing a mean-center method to select the initial center of mass.Meanwhile,we design the K-anonymity algorithm of this scheme based on the constructed information loss function,the improved 2-means clustering algorithm,and the greedy algorithm,which reduces the information loss.Finally,we experimentally demonstrate the effectiveness of the algorithm in improving the effect of 2-means clustering and reducing information loss. 展开更多
关键词 Blockchain big data K-ANONYMITY 2-means clustering greedy algorithm mean-center method
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基于Sentinel-1和Sentinel-2数据融合的森林林龄反演和动态监测
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作者 陈馨 孙玉军 丁志丹 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第6期19-29,共11页
【目的】在Google Earth Engine(GEE)云平台上借助其强大的计算和数据存储能力,融合多源遥感数据对森林林龄进行遥感反演和动态监测。【方法】融合2017—2023年间Sentinel-1、Sentinel-2及高程数据,通过随机森林(Random forest,RF)分类... 【目的】在Google Earth Engine(GEE)云平台上借助其强大的计算和数据存储能力,融合多源遥感数据对森林林龄进行遥感反演和动态监测。【方法】融合2017—2023年间Sentinel-1、Sentinel-2及高程数据,通过随机森林(Random forest,RF)分类获取土地覆盖信息,并进一步提取森林的分布和面积,同时构建时间序列植被指数来准确提取森林变化区域。基于森林资源清查数据和融合的多源遥感数据,在GEE上构建RF回归、分类回归树(Cart)以及梯度提升回归树(Gradient tree boost,GTB)3种回归模型,用于杉木组、马尾松组、毛竹林、硬阔叶树组以及其他类树种组的2018年林龄遥感反演,并估算出2017年和2023年的林龄信息,以揭示林龄和龄组在2017—2023年的动态变化情况。【结果】1)2017—2023年,研究区森林面积的整体变化总计113.93 km^(2),此间森林的减少和更新并存,其空间分布特征呈现出明显的区域差异。具体而言,森林面积变化多发生于靠近城区和低海拔地区,且靠近城区的森林面积减少往往不再恢复至森林;2)在5种不同树种组构建的3种模型中,RF回归模型的林龄反演结果最佳,平均R^(2)为0.845,平均RMSE为5.32 a,其中毛竹林反演精度最高,R^(2)为0.863,RMSE为2.411 a;3)2017—2023年,研究区林龄在40 a以下的森林由54.59%减少至51.06%,其中龄组变化最显著为杉木组成熟林,面积增加了38.88%。【结论】在GEE上融合多源遥感数据进行林龄反演和动态监测具有重要的应用潜力,本研究结果可为使用云平台及哨兵系列卫星数据对森林资源长时间序列的林龄反演和动态监测的应用提供参考和借鉴。 展开更多
关键词 数据融合 遥感反演 林龄 动态监测 Sentinel-1 Sentinel-2 Google Earth Engine
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基于数据挖掘探讨2型糖尿病合并非酒精性脂肪性肝病的中医用药规律
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作者 谢菊 彭思涵 +1 位作者 刘桠 谢春光 《云南中医中药杂志》 2024年第10期22-28,共7页
目的利用“中医传承辅助平台(V2.5)”挖掘中医药治疗2型糖尿病合并非酒精性脂肪性肝病的用药规律,探索新组方为临床治疗提供思路。方法检索建库至2023年10月31日期间中国知网(CNKI)、维普(VIP)、万方数据知识服务平台(WanFang Data)中... 目的利用“中医传承辅助平台(V2.5)”挖掘中医药治疗2型糖尿病合并非酒精性脂肪性肝病的用药规律,探索新组方为临床治疗提供思路。方法检索建库至2023年10月31日期间中国知网(CNKI)、维普(VIP)、万方数据知识服务平台(WanFang Data)中与中医药治疗2型糖尿病合并非酒精性脂肪性肝病相关的文献,将数据整理后录入“中医传承辅助平台(V2.5)”,通过建立独立的数据库对录入数据进行归纳与分析,挖掘用药规律。结果筛选出处方81首,涉及药物137味;使用频次排在前10位的是丹参、柴胡、黄芪、山楂、黄连、白术、茯苓、泽泻、白芍、郁金;药性多以寒、温、平为主,药味多苦甘辛,使用药物主要归脾、肝、胃经;并通过层次聚类分析挖掘出6个核心组合以及3个可能具有潜在临床价值的新组方。结论临床治疗2型糖尿病合并非酒精性脂肪性肝病的治法以“健脾行气,活血利湿”为主,使用频次最高的药物为丹参,药性多寒,药味以苦味为主,使用药物主要归脾经,挖掘结果为新处方的研发提供了一定的参考依据。 展开更多
关键词 中医药 2型糖尿病合并非酒精性脂肪性肝病 数据挖掘 用药规律
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基于Sentinel-2影像的果树提取方法及其空间分析研究——以甘肃省平凉市为例
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作者 柳涛 盖艾鸿 +3 位作者 赵鹏伟 刘桦 鲁聪聪 李莺莺 《江苏林业科技》 2024年第3期22-29,共8页
利用遥感技术对果园进行快速监测,准确掌握苹果园地面积与空间种植分布状况,有助于促进当地经济的发展。目前针对丘陵区果园提取的研究较少,相关方法的有效性和可靠性仍然存在问题。以甘肃省平凉市为研究区域,采用NDVI,RVI,EVI,SIPI,LSW... 利用遥感技术对果园进行快速监测,准确掌握苹果园地面积与空间种植分布状况,有助于促进当地经济的发展。目前针对丘陵区果园提取的研究较少,相关方法的有效性和可靠性仍然存在问题。以甘肃省平凉市为研究区域,采用NDVI,RVI,EVI,SIPI,LSWI,NDWI等指标对输入数据进行增强,通过基于数据增强的梯度提升树算法提取研究区苹果种植面积。为验证该方法的有效性,引入最小距离法、CART决策树法、支持向量机法和随机森林4种机器学习算法进行对比分析,结果表明,梯度提升树算法分类精度最高,总体分类精度(Overall Accuracy,OA)达到89.3%,Kappa系数为0.77,分类效果及一致性均最佳。此外,采用基于数据增强的梯度提升树法分别对2019—2023年的苹果园进行提取,获得平凉市苹果园种植变化情况,各区县苹果园种植面积除泾川县外整体呈现上升趋势,泾川县和静宁县种植面积最大,其次为庄浪县、灵台县和崆峒区,最小的为崇信县和华亭市。 展开更多
关键词 遥感 梯度提升树 数据增强 Sentinel-2影像 Kappa系数 平凉市
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基于多源卫星XCO_(2)数据的融合与优化
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作者 鞠巍 王瑞 《工业控制计算机》 2024年第1期82-83,共2页
随着卫星观测技术的不断发展,包括CO_(2)在内的越来越多的大气成分数据可供获取。多源卫星数据融合是一种有效的手段,可以提高数据的准确性以及时空分辨率。基于压缩感知以及深度学习技术对GOSAT、OCO-2、OCO-3三颗被动式探测卫星的遥... 随着卫星观测技术的不断发展,包括CO_(2)在内的越来越多的大气成分数据可供获取。多源卫星数据融合是一种有效的手段,可以提高数据的准确性以及时空分辨率。基于压缩感知以及深度学习技术对GOSAT、OCO-2、OCO-3三颗被动式探测卫星的遥感观测数据进行了融合与优化。压缩感知用于生成初始的融合数据,深度学习模型进一步强化CO_(2)数据的季节循环特征,对初始融合数据进一步优化。实验结果表明,压缩感知生成的融合数据优于原始卫星观测,深度学习模型能够有效地对融合数据进行降噪与优化。 展开更多
关键词 XCO_(2) 数据融合 压缩感知 深度学习
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烟酰胺腺嘌呤二核苷酸磷酸氧化酶2对老年颅脑损伤患者的影响
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作者 崔茜 杨丽梅 +1 位作者 常玉平 王晓晔 《中华老年心脑血管病杂志》 CAS 北大核心 2024年第9期1073-1078,共6页
目的 探讨血清还原烟酰胺腺嘌呤二核苷酸磷酸氧化酶2(nicotinamide adenine dinucleotide phosphate reduced oxidase 2,NOX2)水平与老年颅脑损伤患者脑组织血供和预后的相关性。方法 选取2019年1月至2022年12月邯郸市人民医院神内一科... 目的 探讨血清还原烟酰胺腺嘌呤二核苷酸磷酸氧化酶2(nicotinamide adenine dinucleotide phosphate reduced oxidase 2,NOX2)水平与老年颅脑损伤患者脑组织血供和预后的相关性。方法 选取2019年1月至2022年12月邯郸市人民医院神内一科收治的老年颅脑损伤患者86例作为颅脑损伤组,另选取同期年龄、性别相匹配的老年健康体检者80例作为对照组。颅脑损伤组根据入院时格拉斯哥昏迷评分(Glasgow coma score, GCS)分为轻型组22例,中型组35例和重型组29例。颅脑损伤组治疗后6个月根据格拉斯哥预后评分(Glasgow outcome score, GOS)分为预后良好组54例和预后不良组32例。比较各组血清NOX2水平和脑血流指标动态变化,分析其与预后GOS评分的相关性。结果 与对照组比较,颅脑损伤组1、3、5、7、10 d的平均血流速度(mean blood flow velocity, Vm)、局部脑血流量(region cerebral blood flow, rCBF)、局部脑血容量(region cerebral blood volume, rCBV)显著降低,血清NOX2水平显著升高(P<0.01)。不同程度颅脑损伤组1、3、5、7、10 d血清NOX2水平比较,差异有统计学意义(P<0.05,P<0.01)。颅脑损伤组1、3、5、7、10、14 d血清NOX2水平与入院时GCS评分呈负相关(r=-0.413、-0.427、-0.515、-0.592、-0.566、-0.338,P<0.01),1、3、5、7、10 d的Vm、rCBV、rCBF与GCS评分呈正相关(r=0.392、0.379、0.407、0.418、0.420,P<0.01;r=0.404、0.414、0.429、0.419、0.428,P<0.01;r=0.412、0.427、0.432、0.428、0.393,P<0.01)。颅脑损伤组1、3、5、7、10 d血清NOX2水平与Vm、rCBV、rCBF呈负相关(P<0.01)。预后不良组1、3、5、7、10、14 d血清NOX2水平显著高于预后良好组,Vm、rCBV、rCBF显著低于预后良好组(P<0.05,P<0.01)。颅脑损伤组1、3、5、7、10、14 d血清NOX2水平与治疗后6个月GOS评分呈负相关,Vm、rCBV、rCBF与GOS评分呈正相关(P<0.01)。结论 血清NOX2水平升高与老年颅脑损伤患者脑组织血供不足和预后不良密切相关,动态监测血清NOX2水平和脑血流指标变化对颅脑损伤预后评估有重要临床意义。 展开更多
关键词 脑损伤 创伤性 NADPH氧化酶2 预后 数据相关性
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