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简介：摘 要：通过主动遥感的SAR雷达数据与被动遥感的多光谱遥感数据进行水体信息提取已成为重要的研究热点之一。本文将借助Sentinel-1和Sentinel-2的雷达数据与多光谱数据进行影像融合，并利用随机森林机器学习方法进行渭河段水体信息的提取。

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简介：摘要：Sentinel影像的高分辨率和海量数据为应用提供了广阔的空间。然而，由于大气散射和吸收对遥感图像质量的影响，遥感图像在实际应用中经常受到大气干扰。基于此，该文提出了一种基于Python的Sentinel影像大气校正方法。首先，采用6S模型对大气参数进行反演，然后对影像进行辐射校正。校正后影像光谱曲线与地面实测光谱曲线的变化趋势一致,具有较高的拟合度。模型大气校正的结果具有较强的相关性和较高的精度。实验结果表明，该方法能够有效地降低Sentinel影像的大气干扰，提高遥感图像的质量和信度。

简介：在围栏设施方面。尤其在扶手栏杆的设计上，Betafence在传统意义上迈进了一大步。Sentinel扶手栏杆不仅具有传统设计的所有特色，并且形式美观：扶手给人的感觉并不夸张、设计典雅。Sentinel系列扶手栏杆共有四种类型：SentinelConvexPlay是安放在儿童玩耍环境的理想设施,如游乐场和公园内：

简介：2012年12月19日Norbain公司技术总监AndrewPigram称：“Norbain公司很高兴地宣布SiLentSentinel公司成为其专业安全设备供应商之一。SilentSentinel公司是英国一家高性能、坚固耐用摄像机系统和先进摄像机定位系统制造商。

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简介：AbstractBackground:Methylene blue is the most commonly used tracer for sentinel lymph node (SLN) biopsy (SLNB) in China. This study aimed to investigate the feasibility of clinical application of SLNB using methylene blue dye (MBD) for early breast cancer and the prognosis of patients with different SLN and non-SLN statuses.Methods:We retrospectively analyzed the clinicopathological data of patients with early breast cancer treated at the Peking University First Hospital between 2013 and 2018. We calculated the SLN identification rate (IR) in SLNB with MBD and the false-negative rate (FNR), and analyzed the prognosis of patients with different SLN and non-SLN statuses using Kaplan-Meier curves.Results:Between January 2013 and December 2018, 1603 patients with early breast cancer underwent SLNB with MBD. The SLN IR was 95.8% (1536/1603). Two SLNs (median) were detected per patient. There were significant differences in FNR between patients with SLN micrometastasis and macrometastasis (19.0% vs. 4.5%, χ2 = 12.771, P < 0.001). Chi-square test showed that there were significant differences in SLN successful detection rates among patients with different vascular tumor embolism status (96.3% vs. 90.8%, χ2 = 9.013, P = 0.003) and tumor (T) stages (96.6% vs. 94.1%, χ2 = 5.189, P = 0.023). Multivariate analysis showed that vascular tumor embolism was the only independent factor for SLN successful detection (odds ratio: 0.440, 95% confidence interval: 0.224-0.862, P = 0.017). Survival analysis showed a significant difference in disease-free survival (DFS) between patients with non-SLN metastasis and patients without non-SLN metastasis (P = 0.006).Conclusion:Our single-center data show that, as a commonly used tracer in SLNB in China, MBD has an acceptable SLN IR and a low FNR in frozen sections. This finding is consistent with reports of dual tracer-guided SLNB. Positive SLNs with non-SLN metastasis are associated with DFS.

简介：摘要：  基于北京地区29景2018年1月3日至2018年12月29日的Sentinel-1数据，利用SARScape软件采用PS-InSAR技术获取地表沉降信息，获取的沉降成果精度可以达到毫米级别。对实验结果分析得出 ：（1）北京市三环内区域内沉降差异性特征明显，而且形状大小不一；（2）西城区沉降部分地区出现小面积的沉降，沉降区域多为高层建筑与地下设施密集；（3）东、西城区地层都比较稳定，均未出现大面积沉降，其最大沉降速率为-5.863mm/y。

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简介：Objective:Thisrandomizedstudyaimedtocomparetheclinicalefficacybetweenthenoveldualtracercomposedofindocyaninegreen(ICG)andbluedye(BD)andtheconventionaldualtracercomposedofradioisotopeandBDforsentinellymphnode(SLN)mappinginpatientswithbreastcancer.Methods:Thisstudyenrolled471clinicallylymphnode-negativepatientswithprimarybreastcancer.Allpatientsunderwentmastectomy,andthoseundergoingsentinellymphnodebiopsy(SLNB)wererandomizedtoreceivebluedyeplusradioisotope(RBgroup)orBDplusICG(IBgroup).ThedetectionperformancesonSLNidentificationrate,positiveSLNcounts,detectionsensitivity,andfalse-negativeratewerecomparedbetweenthetwogroups.Results:IntheIBgroup,97%(194/200)ofthepatientswhounderwenttheICGandBDdualtracerinjectionshowedfluorescentpositivelymphaticvesselswithin2–5min.TheidentificationrateofSLNswascomparablebetweentheIBgroup(99.0%,198/200)andtheRBgroup(99.6%,270/271)(P=0.79).NosignificantdifferenceswereobservedintheidentificationrateofmetastaticSLNs(22.5%vs.22.9%,P>0.05,RBgroupvs.IBgroup,thesamebelow),positiveSLNcounts(3.72±2.28vs.3.91±2.13,P>0.05),positivemetastaticSLNcounts(0.38±0.84vs.0.34±0.78,P>0.05),SLNBdetectionsensitivity(94.4%vs.92.5%,P>0.05),orfalse-negativerate(5.6%vs.7.5%,P>0.05)betweenthetwogroups.Conclusions:ICGcanbeusedasapromisingalternativetracerforradioisotopeinSLNmapping,andwhenitiscombinedwithBDinlymphangiography,itofferscomparabledetectionsensitivitycomparedtotheconventionallymphaticmappingstrategiesthatarewidelyusedinclinicalpractice.

简介：摘要：本研究利用岷江中下游的Sentinel-2影像和总磷浓度实测数据，以单波段和波段组合后的反射率为输入变量，对比了一元线性和非线性回归模型与三种常见的机器学习回归模型对总磷浓度的反演精度，实验表明，BP神经网络模型具有最高的预测精度和较强的泛化性，其决定系数为0.81，RMSE为0.029mg.L 。通过BP神经网络模型对岷江中下游地区的总磷浓度进行反演，揭示了研究区总磷浓度的空间分布状况，对总磷浓度的分布和影响因素进行了分析，为进一步的研究提供了一定的理论和实践价值。

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简介：AbstractThis review analyzes the state and recent progress in the field of information support for pollen allergy sufferers. For decades, information available for the patients and allergologists consisted of pollen counts, which are vital but insufficient. New technology paves the way to substantial increase in amount and diversity of the data. This paper reviews old and newly suggested methods to predict pollen and air pollutant concentrations in the air and proposes an allergy risk concept, which combines the pollen and pollution information and transforms it into a qualitative risk index. This new index is available in an app (Mobile Airways Sentinel NetworK-air) that was developed in the frame of the European Union grant Impact of Air POLLution on sleep, Asthma and Rhinitis (a project of European Institute of Innovation and Technology-Health). On-going transformation of the pollen allergy information support is based on new technological solutions for pollen and air quality monitoring and predictions. The new information-technology and artificial-intelligence-based solutions help to convert this information into easy-to-use services for both medical practitioners and allergy sufferers.

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