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Open Thoracic Surgery for Removal of a Two-Year-Old Impacted Esophageal Coin 认领
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作者 Isaac Okyere Samuel Gyasi Brenu Perditer Okyere 《胸外科期刊(英文)》 2020年第1期32-40,共9页
Introduction: Esophageal foreign bodies are important and serious cause of morbidity and mortality in both children and adults, usually as a result of serious complications, such as perforation, necrosis, mediastiniti... Introduction: Esophageal foreign bodies are important and serious cause of morbidity and mortality in both children and adults, usually as a result of serious complications, such as perforation, necrosis, mediastinitis, and fistulation. Therefore, rapid and accurate diagnosis with subsequent removal is very important. Clinical Case: We present and discuss the presentation, diagnosis and surgical management of a 6-year-old with a 2-year history of ingested coin locked in the oesophagus. Discussion: Diagnosis was established by upper gastrointestinal endoscopy, barium swallow and chest x-ray. The coin was removed by open surgery via oesophagotomy through right thoracotomy after failed retrieval via rigid oesophagoscopy. Conclusion: Surgical treatment in the form of esophagotomy via thoracotomy may be necessary in some cases of impacted foreign bodies in the esophagus where endoscopic removal is unsuccessful. 展开更多
关键词 Foreign Body ESOPHAGUS RETRIEVAL THORACOTOMY COIN
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基于Power BI工具的大数据分析在医疗设备多维数据分析中的应用研究 认领
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作者 王瑜 鲍鲲 +1 位作者 黄婷婷 邵新 《中国医学装备》 2020年第5期169-173,共5页
目的:基于PowerBI工具的大数据分析,构建多维数据检索系统,提高设备利用率。方法:利用医疗设备档案数据原型、数据仓库理论及Power BI工具设计多维数据检索系统,采用Power Query、PowerPivot和Power View等模块工具,在医疗设备档案相关... 目的:基于PowerBI工具的大数据分析,构建多维数据检索系统,提高设备利用率。方法:利用医疗设备档案数据原型、数据仓库理论及Power BI工具设计多维数据检索系统,采用Power Query、PowerPivot和Power View等模块工具,在医疗设备档案相关业务系统间建立数据连接,通过构建数据模型、转换及整合等方法实现数据自动化抽取功能。基于数据模型建立抽象查询原型,在业务中实例化数据检索功能,从而满足医疗设备档案多维数据快速、高效检索的现实需求。结果:医疗设备多维数据检索系统实现了不同业务系统间的数据整合和数据多维检索及动态展现,系统测试中,针对120万条关联测试记录进行单条件跨库查询,多维数据检索系统的平均查询速度为48 ms,是手工跨库查询的16倍,提高了医疗设备检索效率。结论:基于PowerBI工具的多维数据检索系统可满足医疗设备管理中普遍存在的数据采集、检索、分析及展示等现实需求和数据整合,支持异构化数据集成及业务扩展,能提高医疗设备档案管理的科学性。 展开更多
关键词 Power BI工具 医疗设备 多维数据 应用系统 检索
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基于AHI观测的全天气条件海表温度反演 认领
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作者 王朋 诸葛小勇 +3 位作者 陈宝君 陆一磊 肖宇昕 夏凡 《气象科学》 北大核心 2020年第2期249-256,共8页
基于搭载在日本新一代静止气象卫星Himawari-8上的先进葵花成像仪(Advanced Himawari Imager,AHI)观测资料,研究了高时空分辨率的、全天气条件的海表温度(Sea Surface Temperature,SST)反演算法。本算法包括两步:第一步,根据云检测算法... 基于搭载在日本新一代静止气象卫星Himawari-8上的先进葵花成像仪(Advanced Himawari Imager,AHI)观测资料,研究了高时空分辨率的、全天气条件的海表温度(Sea Surface Temperature,SST)反演算法。本算法包括两步:第一步,根据云检测算法划分晴空和云区,然后利用非线性SST(NLSST)方程由红外亮温估计晴空SST;第二步,在有云区,先由前5 d同一时刻的晴空SST进行初步补缺,然后再利用Barnes插值完善云区SST估计和进行异常点平滑。最终得到时间分辨率为10 min、空间分辨率为0.05°的全天气条件海温分布。利用移动浮标的观测SST验证,晴空区SST估计的均方根误差(Root Mean Square Error,RMSE)和平均误差(Mean Error,ME)分别为0.857 K和0.017 K。全天气条件SST估计的RMSE和ME分别为0.872 K和-0.005 K。 展开更多
关键词 海表温度 反演 Himawari-8 全天气条件
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对象检索的分布式数据库系统应用 认领
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作者 王晓燕 刘荷花 孙泰 《太原学院学报:自然科学版》 2020年第1期68-72,共5页
通过对象检索的分布式计算机数据库系统的应用分析,解决了计算机网络资源条件受限以及服务器拥塞的相关问题。分区域微管理,减少了任务服务器和仲裁服务器的处理负荷,避免了服务器的拥塞,从而提高了文件提取的效率,计算出每一个关键词... 通过对象检索的分布式计算机数据库系统的应用分析,解决了计算机网络资源条件受限以及服务器拥塞的相关问题。分区域微管理,减少了任务服务器和仲裁服务器的处理负荷,避免了服务器的拥塞,从而提高了文件提取的效率,计算出每一个关键词对应提取的文件数量,进而计算出各个区域内关键词对应提取的数量,实现各区域公平提取,减少不必要的检索,也提高文件提取的效率。 展开更多
关键词 分布式计算机 检索 数据库 服务器
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Multi-attention based cross-domain beauty product image retrieval 认领
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作者 Zhihui WANG Xing LIU +2 位作者 Jiawen LIN Caifei YANG Haojie LI 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2020年第2期95-97,共3页
Dear editor,In recent years,the Perfect Half Million Beauty Product Image Recognition Challenge has been held by ACM Multi Media 2018[1]for beauty product image retrieval task,and the Perfect-500K dataset has been rel... Dear editor,In recent years,the Perfect Half Million Beauty Product Image Recognition Challenge has been held by ACM Multi Media 2018[1]for beauty product image retrieval task,and the Perfect-500K dataset has been released,acting as a large-scale beauty product dataset. 展开更多
关键词 Multi-attention BASED cross-domain beauty product IMAGE retrieval IMAGE domain
Inverse Fluid-solid Interaction Scattering Problem Using Phased and Phaseless Far Field Data 认领
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作者 Xia JI Yun-fei JIA Xiao-dong LIU 《应用数学学报:英文版》 SCIE CSCD 2020年第1期74-94,共21页
We consider the inverse fluid-solid interaction scattering of incident plane wave from the knowledge of the phased and phaseless far field patterns.For the phased data,one direct sampling method for location and shape... We consider the inverse fluid-solid interaction scattering of incident plane wave from the knowledge of the phased and phaseless far field patterns.For the phased data,one direct sampling method for location and shape reconstruction is proposed.Only inner product is involved in the computation,which makes it very simple and fast to be implemented.With the help of the factorization of the far field operator,we give a lower bound of the proposed indicator functional for the sampling points inside the elastic body.While for the sampling points outside,we show that the indicator functional decays like the Bessel function as the points go away from the boundaries of the elastic body.We also show that the proposed indicator functional continuously dependents on the far field patterns,which further implies that the novel sampling method is extremely stable with respect to data error.For the phaseless data,to overcome the translation invariance,we consider the scattering of point sources simultaneously.By adding a reference sound-soft obstacle into the scattering system,we show some uniqueness results with phaseless far field data.Numerically,we introduce a phase retrieval algorithm to retrieve the phased data without the additional obstacle.The novel phase retrieval algorithm can also be combined with the sampling method for phased data.We also design two novel direct sampling methods using the phaseless data directly.Finally,some numerical simulations in two dimensions are conducted with noisy data,and the results further verify the effectiveness and robustness of the proposed numerical methods. 展开更多
关键词 fluid-solid interaction SCATTERING DIRECT sampling method FAR field PATTERN phaseless phase RETRIEVAL
Optimization of the OCO-2 Cloud Screening Algorithm and Evaluation against MODIS and TCCON Measurements over Land Surfaces in Europe and Japan 认领
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作者 Sijie CHEN Shuaibo WANG +6 位作者 Lin SU Changzhe DONG Ju KE Zhuofan ZHENG Chonghui CHENG Bowen TONG Dong LIU 《大气科学进展:英文版》 SCIE CAS CSCD 2020年第4期387-398,共12页
A method to tighten the cloud screening thresholds based on local conditions is used to provide more stringent schemes for Orbiting Carbon Observatory-2(OCO-2)cloud screening algorithms.Cloud screening strategies are ... A method to tighten the cloud screening thresholds based on local conditions is used to provide more stringent schemes for Orbiting Carbon Observatory-2(OCO-2)cloud screening algorithms.Cloud screening strategies are essential to remove scenes with significant cloud and/or aerosol contamination from OCO-2 observations,which helps to save on the data processing cost and ensure high quality retrievals of the column-averaged CO2 dry air mole fraction(XCO2).Based on the radiance measurements in the 0.76μm O2A band,1.61μm(weak),and 2.06μm(strong)CO2 bands,the current combination of the A-Band Preprocessor(ABP)algorithm and Iterative Maximum A Posteriori(IMAP)Differential Optical Absorption Spectroscopy(DOAS)Preprocessor(IDP)algorithm passes around 20%-25%of all soundings,which means that some contaminated scenes also pass the screening process.In this work,three independent pairs of threshold parameters used in the ABP and IDP algorithms are sufficiently tuned until the overall pass rate is close to the monthly clear-sky fraction from the MODIS cloud mask.The tightened thresholds are applied to observations over land surfaces in Europe and Japan in 2016.The results show improvement of agreement and positive predictive value compared to the collocated MODIS cloud mask,especially in summer and fall.In addition,analysis indicates that XCO2 retrievals with more stringent thresholds are in closer agreement with measurements from collocated Total Carbon Column Observing Network(TCCON)sites. 展开更多
关键词 CLOUD SCREENING CO2 RETRIEVAL OCO-2 MODIS TCCON
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Prognostic importance of lymph node yield after curative resection of gastroenteropancreatic neuroendocrine tumours 认领
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作者 Jaseela Chiramel Rose Almond +11 位作者 Astrid Slagter Adeel Khan Xin Wang Kok Haw Jonathan Lim Melissa Frizziero Bipasha Chakrabarty Annamaria Minicozzi Angela Lamarca Wasat Mansoor Richard A Hubner Juan William Valle Mairéad Geraldine McNamara 《世界临床肿瘤学杂志:英文版》 CAS 2020年第4期205-216,共12页
BACKGROUND The prognostic significance of lymph nodes(LNs)metastases and the optimum number of LN yield in gastroenteropancreatic neuroendocrine tumours(GEP NETs)undergoing curative resection is still debatable.Many s... BACKGROUND The prognostic significance of lymph nodes(LNs)metastases and the optimum number of LN yield in gastroenteropancreatic neuroendocrine tumours(GEP NETs)undergoing curative resection is still debatable.Many studies have demonstrated that cure rate for patients with GEP NETs can be improved by the resection of the primary tumour and regional lymphadenectomy AIM To evaluate the effect of lymph node(LN)status and yield on relapse-free survival(RFS)and overall survival(OS)in patients with resected GEP NETs.METHODS Data on patients who underwent curative resection for GEP NETs between January 2002 and March 2017 were analysed retrospectively.Grade 3 tumours(Ki67>20%)were excluded.Univariate Cox proportional hazard models were computed for RFS and OS and assessed alongside cut-point analysis to distinguish a suitable binary categorisation of total LNs retrieved associated with RFS.RESULTS A total of 217 patients were included in the study.The median age was 59 years(21-97 years)and 51%(n=111)were male.Primary tumour sites were small bowel(42%),pancreas(25%),appendix(18%),rectum(7%),colon(3%),gastric(2%),others(2%).Median follow up times for all patients were 41 mo(95%CI:36-51)and 71 mo(95%CI:63–76)for RFS and OS respectively;50 relapses and 35 deaths were reported.LNs were retrieved in 151 patients.Eight or more LNs were harvested in 106 patients and LN positivity reported in 114 patients.Three or more positive LNs were detected in 62 cases.The result of univariate analysis suggested perineural invasion(P=0.0023),LN positivity(P=0.033),LN retrieval of≥8(P=0.047)and localisation(P=0.0049)have a statistically significant association with shorter RFS,but there was no effect of LN ratio on RFS:P=0.1 or OS:P=0.75.Tumour necrosis(P=0.021)and perineural invasion(P=0.016)were the only two variables significantly associated with worse OS.In the final multivariable analysis,localisation(pancreas HR=27.33,P=0.006,small bowel HR=32.44,P=0.005),and retrieval of≥8 LNs(HR=2.7,P=0.036)were independent prognostic factors 展开更多
关键词 Well differentiated NEUROENDOCRINE tumours Pancreatic NEUROENDOCRINE tumours Small intestinal NEUROENDOCRINE tumours Ki67 LYMPH NODE ratio LYMPH NODE retrieval LYMPH NODE POSITIVITY Relapse-free SURVIVAL Overall SURVIVAL
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手机软件用户界面检索综述 认领
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作者 张志翔 王慧亚 范佳琪 《现代计算机》 2020年第9期41-44,48共5页
构建原型设计模型在手机软件的开发流程中是十分复杂且可重用的一环,所以研究用户界面的检索问题是有必要的。相较于电脑软件界面,手机软件界面具有更强的图形性,一个优秀的图形化用户界面在市场上更具有竞争力。现今的检索的方式主要... 构建原型设计模型在手机软件的开发流程中是十分复杂且可重用的一环,所以研究用户界面的检索问题是有必要的。相较于电脑软件界面,手机软件界面具有更强的图形性,一个优秀的图形化用户界面在市场上更具有竞争力。现今的检索的方式主要有基于草图、UI模型、屏幕截图、关键词和条件筛选或者组合搜索,检索所用的数据库主要有Rico、ERICA以及一些通用的网站数据库如GitHub等。 展开更多
关键词 用户界面 检索 计算机视觉
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免疫进化算法反演均匀混合气溶胶吸湿增长因子 认领
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作者 张智察 倪长健 +2 位作者 邓也 张莹 杨寅山 《中国环境科学》 EI CAS CSCD 北大核心 2020年第3期1008-1015,共8页
通过对大气消光系数进行组分分解,并借助米散射理论,构建了以均匀混合气溶胶吸湿增长因子为唯一变量的目标函数.进一步利用免疫进化算法优化该目标函数,提出了一种针对均匀混合气溶胶吸湿增长因子的反演算法.基于成都市2017年10-12月浊... 通过对大气消光系数进行组分分解,并借助米散射理论,构建了以均匀混合气溶胶吸湿增长因子为唯一变量的目标函数.进一步利用免疫进化算法优化该目标函数,提出了一种针对均匀混合气溶胶吸湿增长因子的反演算法.基于成都市2017年10-12月浊度计,黑碳仪和GRIMM180环境颗粒物监测仪的地面逐时观测资料以及该时段同时次的环境气象监测数据(大气能见度,相对湿度RH和NO2质量浓度),评估了算法的性能及其适用性.结果表明:对所有测试样本而言,反演均匀混合气溶胶吸湿增长因子的免疫进化算法均能快速收敛到全局最优解.建立了成都地区秋冬季均匀混合气溶胶吸湿增长模型,该模型显著提升了环境条件下气溶胶散射系数的模拟精度,其模拟值与实测值之间的平均相对误差仅为12.7%.该反演算法的普适性可为气溶胶吸湿性及其辐射强迫效应的后续研究提供算法保障. 展开更多
关键词 气溶胶 米散射理论 吸湿增长因子 反演 免疫进化算法
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基于地基遥感的降水过程对城市型气溶胶差异性影响分析 认领
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作者 董佳丹 陈晓玲 +4 位作者 蔡晓斌 关宇廷 徐强强 李婷慧 陈芳 《华中师范大学学报:自然科学版》 CAS CSCD 北大核心 2020年第3期463-471,共9页
降水过程对气溶胶粒子的影响非常复杂.为了研究降水对城市大气中气溶胶粒子的差异性影响,该文选择2016年6~7月武汉市一次持续性强降水过程进行分析.结合OPAC模型及GADS数据集,利用最小二乘线性回归算法,基于CE-318太阳光度计及黑碳仪观... 降水过程对气溶胶粒子的影响非常复杂.为了研究降水对城市大气中气溶胶粒子的差异性影响,该文选择2016年6~7月武汉市一次持续性强降水过程进行分析.结合OPAC模型及GADS数据集,利用最小二乘线性回归算法,基于CE-318太阳光度计及黑碳仪观测数据对大气中三种城市气溶胶粒子(不溶性气溶胶粒子INSO、水溶性气溶胶粒子WASO、黑碳气溶胶SOOT)的粒子数密度进行反演,并使用光学特性误差及黑碳仪观测结果对反演结果进行验证,显示了较高的反演精度.通过对比降水前后不同气溶胶粒子数量的变化,发现降水对INSO、WASO、SOOT三种气溶胶的影响效果及时长存在明显差异.降水对WASO、INSO、SOOT均有明显的抑制作用,但影响时长存在明显差异.降水对SOOT的消减作用仅能持续数小时.WASO在降水后逐渐回升,其抑制作用仅能持续一周即回复到降水前,降水对INSO消减作用的持续时间最长,可达数周之久. 展开更多
关键词 降水 气溶胶 太阳光度计 OPAC 成分和粒子数密度反演 黑碳仪
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基于特征检索的中文短评生成 认领
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作者 袁江林 陈刚 +1 位作者 郭志刚 唐永旺 《计算机工程与设计》 北大核心 2020年第4期1158-1163,共6页
针对从大数据评论语料库中检索出与新闻主题相关且含有情感倾向性的中文评论的研究较少的问题,研究在不同新闻粒度下的特征检索方法,从中文评论语料库中检索生成评论。采用主题特征检索的方法检索出与新闻主题特征相关的评论;采用情感... 针对从大数据评论语料库中检索出与新闻主题相关且含有情感倾向性的中文评论的研究较少的问题,研究在不同新闻粒度下的特征检索方法,从中文评论语料库中检索生成评论。采用主题特征检索的方法检索出与新闻主题特征相关的评论;采用情感特征融合的检索方法从主题特征检索的结果中生成所需情感倾向性的评论。实验结果表明,在新闻标题粒度下生成评论的主题相关性最高;采用主题特征融合的检索方法和情感特征融合的检索方法比单一检索方法生成准确率更高。 展开更多
关键词 中文评论 主题特征 情感特征 检索 分类 融合
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无线局域网内敏感信息安全检索仿真 认领
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作者 刘香伟 马昕 《计算机仿真》 北大核心 2020年第1期259-262,共4页
针对传统方法对无线局域网内敏感信息进行检索时,存在检索安全性较差的问题,提出一种新的无线局域网内敏感信息安全检索方法。设计由信息拥有者、信息查询者、云服务器以及三方管理机构构成的多用户系统。在无线局域网环境下下形成私钥... 针对传统方法对无线局域网内敏感信息进行检索时,存在检索安全性较差的问题,提出一种新的无线局域网内敏感信息安全检索方法。设计由信息拥有者、信息查询者、云服务器以及三方管理机构构成的多用户系统。在无线局域网环境下下形成私钥与公钥,令网络信息拥有者从含大量文件的信息集中对敏感信息集合进行提取,由网络文件向量组成可搜索索引,从而完成多个敏感信息的自动加密,采用模糊加密算法将加密的敏感信息集合与安全的索引传输至云服务器端完成信息检索。实验结果表明,与传统方法相比,所提方法不仅有较强的抗关键字猜测攻击性能,而且计算代价小,检索安全性较高。 展开更多
关键词 无线局域网 敏感信息 加密 检索
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大规模科技文献深度解析和检索平台构建 认领
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作者 吴素研 吴江瑞 李文波 《现代情报》 CSSCI 2020年第1期110-115,共6页
[目的/意义]在信息检索、科技论文评价和知识结构演化方面,引文分析都起着至关重要的作用。随着格式化全文数据库的出现,引文分析迈入了4.0时代--全文引文分析阶段。但是,目前还没有中文的格式化全文数据库,这极大地制约了全文引文分析... [目的/意义]在信息检索、科技论文评价和知识结构演化方面,引文分析都起着至关重要的作用。随着格式化全文数据库的出现,引文分析迈入了4.0时代--全文引文分析阶段。但是,目前还没有中文的格式化全文数据库,这极大地制约了全文引文分析在我国科技文献中的研究和应用。[方法/过程]在本文中我们提出建立高效的中文全文引文分析依赖的数据集和检索平台的方法,主要包括:1)提出了基于规则和SVM分类方法的论文元数据和引用提取方法;2)提出基于Spark平台的实现高效引文内容分析标准化数据集生成方法;3)提出建立引用内容的科技文献检索平台。[结果/结论]引文内容分析标准化数据集的建立将全面提升全文引文分析在我国科技领域中的研究效能,提高科技文献查找精度。 展开更多
关键词 全文引文分析 信息抽取 信息检索 SPARK
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Validation of MODIS ocean-colour products in the coastal waters of the Yellow Sea and East China Sea 认领
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作者 Lingling Jiang Xiangyu Guo +4 位作者 Lin Wang Shubha Sathyendranath Hayley Evers-King Yanlong Chen Bingnan Li 《海洋学报:英文版》 SCIE CAS CSCD 2020年第1期91-101,共11页
An extensive study collected in situ data along the Yellow Sea(YS) and East China Sea(ECS) to assess the radiometric properties and the concentration of the water constituents derived from Moderate Resolution Imaging ... An extensive study collected in situ data along the Yellow Sea(YS) and East China Sea(ECS) to assess the radiometric properties and the concentration of the water constituents derived from Moderate Resolution Imaging Spectroradiometer(MODIS). Thirteen high quality match-ups were obtained for evaluating the MODIS estimates of Rrs(λ), chlorophyll a(Chl a) and concentrations of suspended particulate sediment matter(SPM). For MODIS Rrs(λ), the mean absolute percentage difference(APD) was in the range of 20%–36%, and the highest uncertainty appeared at 412 nm, whereas the band ratio of Rrs(λ) at 488 nm compared with that at 547 nm was highly consistent, with an APD of 7%. A combination of near-infrared bands and shortwave infrared wavelengths atmosphere correction algorithm(NIR-SWIR algorithm) was applied to the MODIS data, and the estimation accuracy of Rrs were improved at most of the visible spectral bands except 645 nm, 667 nm and 678 nm. Two ocean-colour empirical algorithms for Chl a estimation were applied to the processed data, the results indicated that the accuracy of the derived Chl a values was obviously improved, the four-band algorithms outperformed the other algorithm for measured and simulated datasets, and the minimum APD was 35%. The SPM was also quantified. Two regional and two coastal SPM algorithms were modified according to the in situ data. By comparison, the modified Tassan model had a higher accuracy for the application along the YS and ECS with an APD of 21%. However, given the limited match-up dataset and the potential influence of the aerosol properties on atmosphere correction, further research is required to develop additional algorithms especially for the low Chl a coastal water. 展开更多
关键词 MODIS turbid WATERS CHLOROPHYLL a SPM RETRIEVAL algorithms Yellow and East China Sea
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Research on sea surface temperature retrieval by the one-dimensional synthetic aperture microwave radiometer, 1D-SAMR 认领
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作者 Weihua Ai Mengyan Feng +1 位作者 Guanyu Chen Wen Lu 《海洋学报:英文版》 SCIE CAS CSCD 2020年第5期115-122,共8页
Due to the low spatial resolution of sea surface temperature(T_S)retrieval by real aperture microwave radiometers,in this study,an iterative retrieval method that minimizes the differences between brightness temperatu... Due to the low spatial resolution of sea surface temperature(T_S)retrieval by real aperture microwave radiometers,in this study,an iterative retrieval method that minimizes the differences between brightness temperature(T_B)measured and modeled was used to retrieve sea surface temperature with a one-dimensional synthetic aperture microwave radiometer,temporarily named 1 D-SAMR.Regarding the configuration of the radiometer,an angular resolution of 0.43°was reached by theoretical calculation.Experiments on sea surface temperature retrieval were carried out with ideal parameters;the results show that the main factors affecting the retrieval accuracy of sea surface temperature are the accuracy of radiometer calibration and the precision of auxiliary geophysical parameters.In the case of no auxiliary parameter errors,the greatest error in retrieved sea surface temperature is obtained at low T_S scene(i.e.,0.7106 K for the incidence angle of 35°under the radiometer calibration accuracy of0.5 K).While errors on auxiliary parameters are assumed to follow a Gaussian distribution,the greatest error on retrieved sea surface temperature was 1.3305 K at an incidence angle of 65°in poorly known sea surface wind speed(W)(the error on W of 1.0 m/s)over high W scene,for the radiometer calibration accuracy of 0.5 K. 展开更多
关键词 sea surface temperature synthetic aperture microwave radiometer retrieval accuracy radiometer calibration accuracy auxiliary parameter errors high spatial resolution
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Web3D Learning Framework for 3D Shape Retrieval Based on Hybrid Convolutional Neural Networks 认领
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作者 Wen Zhou Jinyuan Jia +1 位作者 Chengxi Huang Yongqing Cheng 《清华大学学报自然科学版(英文版)》 SCIE EI CAS CSCD 2020年第1期93-102,共10页
With the rapid development of Web3 D technologies, sketch-based model retrieval has become an increasingly important challenge, while the application of Virtual Reality and 3 D technologies has made shape retrieval of... With the rapid development of Web3 D technologies, sketch-based model retrieval has become an increasingly important challenge, while the application of Virtual Reality and 3 D technologies has made shape retrieval of furniture over a web browser feasible. In this paper, we propose a learning framework for shape retrieval based on two Siamese VGG-16 Convolutional Neural Networks(CNNs), and a CNN-based hybrid learning algorithm to select the best view for a shape. In this algorithm, the AlexNet and VGG-16 CNN architectures are used to perform classification tasks and to extract features, respectively. In addition, a feature fusion method is used to measure the similarity relation of the output features from the two Siamese networks. The proposed framework can provide new alternatives for furniture retrieval in the Web3 D environment. The primary innovation is in the employment of deep learning methods to solve the challenge of obtaining the best view of 3 D furniture,and to address cross-domain feature learning problems. We conduct an experiment to verify the feasibility of the framework and the results show our approach to be superior in comparison to many mainstream state-of-the-art approaches. 展开更多
关键词 WEB3D sketch-based model RETRIEVAL Convolutional NEURAL Networks(CNNs) best VIEW cross-domain
基于语义和结构的UML类图的检索 认领
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作者 袁中臣 马宗民 《东北大学学报:自然科学版》 EI CAS CSCD 北大核心 2020年第1期23-28,共6页
以软件重用为背景提出基于语义和结构的UML类图检索.构建了UML类图的重用模型,定义了存储UML类图的重用库结构.提出将本体的概念语义距离应用到UML类图的语义相似性度量和使用图表示UML类图的结构进行结构相似性度量.基于检索流程形式... 以软件重用为背景提出基于语义和结构的UML类图检索.构建了UML类图的重用模型,定义了存储UML类图的重用库结构.提出将本体的概念语义距离应用到UML类图的语义相似性度量和使用图表示UML类图的结构进行结构相似性度量.基于检索流程形式化检索需求,提出了UML类图的检索算法.基于提出的衡量标准,从语义、结构和混合三种检索类型对提出的算法进行了验证.实验结果表明,所提出的检索算法在检索质量和检索效率上要优于其他方法. 展开更多
关键词 UML类图 语义 结构 相似性度量 检索
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Borderline form of empty follicle syndrome treated with a novel dual trigger method combined with delayed oocyte retrieval:A case report 认领
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作者 Xian-Ling Cao Zhen-Gao Sun 《世界临床病例杂志》 SCIE 2020年第4期825-830,共6页
BACKGROUND Borderline form of empty follicle syndrome is a condition in which only a few mature or immature oocytes are recovered after meticulous follicular aspiration,despite adequate ovarian response to stimulation... BACKGROUND Borderline form of empty follicle syndrome is a condition in which only a few mature or immature oocytes are recovered after meticulous follicular aspiration,despite adequate ovarian response to stimulation.It is a rare phenomenon with an unclear cause.Currently,the condition still lacks effective treatment.CASE SUMMARY A patient with secondary infertility who had undergone three cycles of assisted reproductive technique(ART)is described.With regard to good follicular response,two oocytes were obtained in the first two ART cycles,but no embryo was formed.In the third ART cycle,which is the subject of this study,ovulation was induced by dual trigger of a supernormal dose of human chorionic gonadotropin(HCG)combined with a delayed oocyte retrieval approach.The method involved administration of gonadotropin-releasing hormone agonist,recombinant HCG,and urinary HCG 39 h before ovum pick-up.Ten oocytes were recovered,two out of three mature eggs were fertilized after intracytoplasmic sperm injection,resulting in two embryos that were subsequently cryopreserved.The case report guidelines have been used herein to present the first case of this novel dual trigger method.CONCLUSION This approach provides a new treatment option for patients with a similar condition in the future.This study can also inspire further investigation on the effects of variousβ-HCG serum levels 36 h after intramuscular HCG administration. 展开更多
关键词 EMPTY follicle syndrome DUAL TRIGGER DELAYED OOCYTE retrieval β-HCG threshold Case report
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RGB and LBP-texture deep nonlinearly fusion features for fabric retrieval 认领
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作者 沈飞 Wei Mengwan +2 位作者 Liu Jiajun Zeng Huanqiang Zhu Jianqing 《高技术通讯:英文版》 EI CAS 2020年第2期196-203,共8页
Fabric retrieval is very challenging since problems like viewpoint variations,illumination changes,blots,and poor image qualities are usually encountered in fabric images.In this work,a novel deep feature nonlinear fu... Fabric retrieval is very challenging since problems like viewpoint variations,illumination changes,blots,and poor image qualities are usually encountered in fabric images.In this work,a novel deep feature nonlinear fusion network(DFNFN)is proposed to nonlinearly fuse features learned from RGB and texture images for improving fabric retrieval.Texture images are obtained by using local binary pattern texture(LBP-Texture)features to describe RGB fabric images.The DFNFN firstly applies two feature learning branches to deal with RGB images and the corresponding LBP-Texture images simultaneously.Each branch contains the same convolutional neural network(CNN)architecture but independently learning parameters.Then,a nonlinear fusion module(NFM)is designed to concatenate the features produced by the two branches and nonlinearly fuse the concatenated features via a convolutional layer followed with a rectified linear unit(ReLU).The NFM is flexible since it can be embedded in different depths of the DFNFN to find the best fusion position.Consequently,DFNFN can optimally fuse features learned from RGB and LBP-Texture images to boost the retrieval accuracy.Extensive experiments on the Fabric 1.0 dataset show that the proposed method is superior to many state-of-the-art methods. 展开更多
关键词 FABRIC RETRIEVAL feature FUSION convolutional neural network(CNN)
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