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2007-2020中国探月工程VLBI测量数据集
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作者 陈中 郑为民 +1 位作者 陈肖 薛岩松 《中国科学数据(中英文网络版)》 CSCD 2022年第1期39-50,共12页
中国探月工程“绕、落、回”历次任务对探测器的飞行轨道测量和着陆点位置测量有很高的精度要求,综合测距、测速和甚长基线干涉测量(VLBI)方法可快速获得探测器的高精度测量结果。基于“嫦娥1号”至“嫦娥5号”任务中国VLBI网实测获得的... 中国探月工程“绕、落、回”历次任务对探测器的飞行轨道测量和着陆点位置测量有很高的精度要求,综合测距、测速和甚长基线干涉测量(VLBI)方法可快速获得探测器的高精度测量结果。基于“嫦娥1号”至“嫦娥5号”任务中国VLBI网实测获得的VLBI数据,建立了“2007–2020中国探月工程VLBI测量数据集”。本数据集时间跨度为2007–2020年,除实时任务数据外,还包含了各个拓展试验任务和长管任务的测量数据集。这些数据具有重要意义,已服务于多个嫦娥任务VLBI新技术方法验证与系统性能评估,支持了多次VLBI测轨任务的圆满完成,对我国后续各项探月工程和行星探测,以及空间天文相关课题的研究,也具有较高的参考价值。 展开更多
关键词 探月工程 VLBI 测量数据集 数据
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基于红外注意力提升机制的热成像测温区域实例分割 被引量:3
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作者 易诗 李俊杰 贾勇 《电子与信息学报》 EI CSCD 北大核心 2021年第12期3505-3512,共8页
AI+热成像人体温度监测系统被广泛用于人群密集的人体实时温度测量。此类系统检测人的头部区域进行温度测量,由于各类遮挡,温度测量区域可能太小而无法正确测量。为了解决这个问题,该文提出一种融合红外注意力提升机制的无锚点实例分割... AI+热成像人体温度监测系统被广泛用于人群密集的人体实时温度测量。此类系统检测人的头部区域进行温度测量,由于各类遮挡,温度测量区域可能太小而无法正确测量。为了解决这个问题,该文提出一种融合红外注意力提升机制的无锚点实例分割网络,用于实时红外热成像温度测量区域实例分割。该文所提出的实例分割网络在检测阶段和分割阶段融合红外空间注意力模块(ISAM),旨在准确分割红外图像中的头部裸露区域,以进行准确实时的温度测量。结合公共热成像面部数据集和采集的红外热成像数据集,制作了"热成像温度测量区域分割数据集"用于网络训练。实验结果表明:该方法对红外热成像图像中头部裸露测温区域的平均检测精度达到88.6%,平均分割精度达到86.5%,平均处理速度达到33.5 fps,在评价指标上优于大多数先进的实例分割方法。 展开更多
关键词 红外热成像 人体体温监测系统 红外注意力提升机制 无锚点实例分割网络 热成像温度测量区域分割数据
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MEASUREMENT TECHNOLOGY OF HEAT AND COOL
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作者 朱春玲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期245-249,共5页
The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua ... The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua lity of modern property management. So the study on the technology of measuring heat and cool is very necessary. In this paper, the detailed thermal analysis and the mathematical model of relative parameters that affect the measurement of heat and cool are discussed. A sample instrument based on the model is made, After the trial use by several customers, the device is proved to be practical, worthwhile and of good capacity. 展开更多
关键词 central air conditioning measurement data acquisition single chip
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Toward Energy-Efficient and Trustworthy eHealth Monitoring System 被引量:1
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作者 Ajmal Sawand Soufiene Djahel +1 位作者 Zonghua Zhang Farid Na?t-Abdesselam 《China Communications》 SCIE CSCD 2015年第1期46-65,共20页
The rapid technological convergence between Internet of Things (loT), Wireless Body Area Networks (WBANs) and cloud computing has made e-healthcare emerge as a promising application domain, which has significant p... The rapid technological convergence between Internet of Things (loT), Wireless Body Area Networks (WBANs) and cloud computing has made e-healthcare emerge as a promising application domain, which has significant potential to improve the quality of medical care. In particular, patient-centric health monitoring plays a vital role in e-healthcare service, involving a set of important operations ranging from medical data collection and aggregation, data transmission and segregation, to data analytics. This survey paper firstly presents an architectural framework to describe the entire monitoring life cycle and highlight the essential service components. More detailed discussions are then devoted to {/em data collection} at patient side, which we argue that it serves as fundamental basis in achieving robust, efficient, and secure health monitoring. Subsequently, a profound discussion of the security threats targeting eHealth monitoring systems is presented, and the major limitations of the existing solutions are analyzed and extensively discussed. Finally, a set of design challenges is identified in order to achieve high quality and secure patient-centric monitoring schemes, along with some potential solutions. 展开更多
关键词 eHealthcare wireless body area networks cyber physical systems mobile crowd sensing security privacy by design trust.
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Spatial Object Aggregation Based on Data Structure, Local Triangulation and Hierarchical Analyzing Method
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作者 LIUYaolin MartienMolenaar 《Geo-Spatial Information Science》 2002年第1期44-54,共11页
This paper focuses on the methods and process of spatial aggregation based on semantic and geometric characteristics of spatial objects and relations among the objects with the help of spatial data structure (Formal D... This paper focuses on the methods and process of spatial aggregation based on semantic and geometric characteristics of spatial objects and relations among the objects with the help of spatial data structure (Formal Data Structure),the Local Constrained Delaunay Triangulations and semantic hierarchy.The adjacent relation among connected objects and unconnected objects has been studied through constrained triangle as elementary processing unit in aggregation operation.The hierarchical semantic analytical matrix is given for analyzing the similarity between objects types and between objects.Several different cases of aggregation have been presented in this paper. 展开更多
关键词 AGGREGATION spatial object HIERARCH data model
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Considerations when using the activPAL monitor in field-based research with adult populations 被引量:5
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作者 Charlotte L.Edwardson Elisabeth A.H.Winkler +4 位作者 Danielle H.Bodicoat Tom Yates Melanie J.Davies David W.Dunstan Genevieve N.Healy 《Journal of Sport and Health Science》 SCIE 2017年第2期162-178,共17页
Research indicates that high levels of sedentary behavior(sitting or lying with low energy expenditure) are adversely associated with health. A key factor in improving our understanding of the impact of sedentary beha... Research indicates that high levels of sedentary behavior(sitting or lying with low energy expenditure) are adversely associated with health. A key factor in improving our understanding of the impact of sedentary behavior(and patterns of sedentary time accumulation) on health is the use of objective measurement tools that collect date and time-stamped activity information. One such tool is the activP AL monitor. This thigh-worn device uses accelerometer-derived information about thigh position to determine the start and end of each period spent sitting/lying, standing, and stepping, as well as stepping speed, step counts, and postural transitions. The activP AL is increasingly being used within field-based research for its ability to measure sitting/lying via posture. We summarise key issues to consider when using the activP AL in physical activity and sedentary behavior field-based research with adult populations. It is intended that the findings and discussion points be informative for researchers who are currently using activP AL monitors or are intending to use them. Pre-data collection decisions, monitor preparation and distribution, data collection considerations, and manual and automated data processing possibilities are presented using examples from current literature and experiences from 2 research groups from the UK and Australia. 展开更多
关键词 populations monitor lying collection accelerometer expenditure Australia stepping currently intended
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Modeling Gross Primary Production by Integrating Satellite Data and Coordinated Flux Measurements in Arid and Semi-Arid China 被引量:1
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作者 WANG He-Song JIA Gen-Suo +2 位作者 FENG Jin-Ming ZHAO Tian-Bao MA Zhu-Guo 《Atmospheric and Oceanic Science Letters》 2010年第1期7-13,共7页
Assessing large-scale patterns of gross primary production (GPP) in arid and semi-arid (ASA) areas is important for both scientific and practical purposes.Remote sensing-based models,which integrate satellite data wit... Assessing large-scale patterns of gross primary production (GPP) in arid and semi-arid (ASA) areas is important for both scientific and practical purposes.Remote sensing-based models,which integrate satellite data with input from ground-based meteorological measurements and vegetation characteristics,improve spatially extended estimates of vegetation productivity with high accuracy.In this study,the authors simulated GPP in ASA areas by integrating moderate resolution imaging spectral radiometer (MODIS) data with eddy covariance and meteorological measurements at the flux tower sites using the Vegetation Photosynthesis Model (VPM),which is a remote sensing-based model for analyzing the spatial pattern of GPP in different land cover types.The field data were collected by coordinating observations at nine stations in 2008.The results indicate that in the region during the growing season GPP was highest in cropland sites,second highest in woodland sites,and lowest in grassland sites.VPM captured the temporal and spatial characteristics of GPP for different land covers in ASA areas.Further,Enhanced Vegetation Index (EVI) had a strong liner relationship with GPP in densely vegetated areas,while the Normalized Difference Vegetation Index (NDVI) had a strong liner relationship with GPP over less dense vegetation.This study demonstrates the potential of satellite-driven models for scaling-up GPP,which is a key component for studying the carbon cycle at regional and global scales. 展开更多
关键词 gross primary production vegetation photo- synthesis model eddy covariance remote sensing coordinated observation arid and semiarid areas
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Electrical capacitance volume tomography for measurement soil water infiltration in vessel experiments
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作者 Muhammad Mukhlisin Marlin Ramadhan Baidillah Mohd Raihan Taha 《Journal of Central South University》 SCIE EI CAS 2014年第1期358-364,共7页
Electrical capacitance volume tomography(ECVT) is a recently-developed technique for real-time,non-invasive 3D monitoring of processes involving materials with strong contrasts in dielectric permittivity.This work is ... Electrical capacitance volume tomography(ECVT) is a recently-developed technique for real-time,non-invasive 3D monitoring of processes involving materials with strong contrasts in dielectric permittivity.This work is first application of the method to visualization of water flow in soil.We describe the principles behind the method,and then demonstrate its use with a simple laboratory infiltration experiment.32 ECVT sensors were installed on the sides of an empty PVC column.Water was poured into the column at a constant rate,and ECVT data were collected every second.The column was then packed with dry sand and again supplied with water at a constant rate with data collected every second.Data were analyzed to give bulk average water contents,which proved consistent with the water supply rates.Data were also analyzed to give 3D images(216 voxels) allowing visualization of the water distribution during the experiments.Result of this work shows that water infiltration into the soil,wall flow,progress of the unstable wetting front and the final water distribution are clearly visible. 展开更多
关键词 soil water infiltration electrical capacitance volume tomography real time imaging
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Understanding human diseases with high-throughput quantitative measurement and analysis of molecular signatures 被引量:2
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作者 YANG Li WEI Gang +2 位作者 TANG Kun NARDINI Christine HAN Jing-Dong J. 《Science China(Life Sciences)》 SCIE CAS 2013年第3期213-219,共7页
Microarray and deep sequencing technologies have provided unprecedented opportunities for mapping genome mutations,RNA transcripts,transcription factor binding,and histone modifications at high resolution at the genom... Microarray and deep sequencing technologies have provided unprecedented opportunities for mapping genome mutations,RNA transcripts,transcription factor binding,and histone modifications at high resolution at the genome-wide level.This has revolutionized the way in which transcriptomes,regulatory networks and epigenetic regulations have been studied and large amounts of heterogeneous data have been generated.Although efforts are being made to integrate these datasets unbiasedly and efficiently,how best to do this still remains a challenge.Here we review major impacts of high-throughput genome-wide data generation,their relevance to human diseases,and various bioinformatics approaches for data integration.Finally,we provide a case study on inflammatory diseases. 展开更多
关键词 GENOMICS EPIGENOMICS PHENOMICS integration data analysis
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Investigate the nonuniformity of low-energy electron beam with large cross-sections 被引量:1
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作者 REN Jie HUANG JianMing +2 位作者 ZHANG YuTian LI DeMing ZHU NanKang 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第4期997-1000,共4页
Over the past decades, low-energy electron accelerators have been used worldwide for surface curing and sterilization. The beam nonuniformity is an important parameter of the low-energy electron beam with large cross-... Over the past decades, low-energy electron accelerators have been used worldwide for surface curing and sterilization. The beam nonuniformity is an important parameter of the low-energy electron beam with large cross-sections. A simple and accurate measurement system of nonuniformity for the low-energy electron beam with large cross-sections was developed. The main concept consists in the measurement of nonuniformity, which is realized by using a linear actuator to drive two scanning wires through the beam's cross-sections at a fixed speed. The beam distribution can be obtained by sending/collecting the current signals to/from the Data Acquisition (DAQ) software on a laptop by a USB DAQ card. This device is very convenient for the performance testing of a new accelerator at the manufacturer's site. The distribution of the homemade low voltage electron accelerator EBS-300-50 was measured and evaluated. 展开更多
关键词 low-energy electron beam large cross-sections electron beam industry accelerator beam nonuniformity measurement
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Unsteady Pressure Measurements in a High-Speed Centrifugal Compressor 被引量:1
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作者 N.Bulot X.Ottavy I.Trebinjac 《Journal of Thermal Science》 SCIE EI CAS CSCD 2010年第1期34-41,共8页
This paper presents the unsteady data acquisition system used to measure the pressure field in high speed compressors.Details and electronic sketches are given for the conditioners developed in-house that have been us... This paper presents the unsteady data acquisition system used to measure the pressure field in high speed compressors.Details and electronic sketches are given for the conditioners developed in-house that have been used to amplify and to filter the pressure signal with the aim of acquiring data up to 150 kHz.A discussion of the experimental results carried out in a centrifugal compressor is proposed.Through different processing of the pressure signals and a comparison with URANS simulations,the excitation of the pressure transducers by the pressure waves generated by shock waves that occur between the impeller and the diffuser is highlighted.The levels of pressure fluctuations measured when entering into surge are also presented and reveal very repetitive behaviour of the flow instabilities. 展开更多
关键词 unsteady pressure measurements CONDITIONER high frequency high speed centrifugal compressor.
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