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Integral experiment on slab^(nat)Pb using D-T and D-D neutron sources to validate evaluated nuclear data
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作者 Kuo-Zhi Xu Yang-Bo Nie +6 位作者 Chang-Lin Lan Yan-Yan Ding Shi-Yu Zhang Qi Zhao Xin-Yi Pan Jie Ren Xi-Chao Ruan 《Nuclear Science and Techniques》 2025年第3期119-133,共15页
Lead(Pb)plays a significant role in the nuclear industry and is extensively used in radiation shielding,radiation protection,neutron moderation,radiation measurements,and various other critical functions.Consequently,... Lead(Pb)plays a significant role in the nuclear industry and is extensively used in radiation shielding,radiation protection,neutron moderation,radiation measurements,and various other critical functions.Consequently,the measurement and evaluation of Pb nuclear data are highly regarded in nuclear scientific research,emphasizing its crucial role in the field.Using the time-of-flight(ToF)method,the neutron leakage spectra from three^(nat)Pb samples were measured at 60°and 120°based on the neutronics integral experimental facility at the China Institute of Atomic Energy(CIAE).The^(nat)Pb sample sizes were30 cm×30 cm×5 cm,30 cm×30 cm×10 cm,and 30 cm×30 cm×15 cm.Neutron sources were generated by the Cockcroft-Walton accelerator,producing approximately 14.5 MeV and 3.5 MeV neutrons through the T(d,n)^(4)He and D(d,n)^(3)He reactions,respectively.Leakage neutron spectra were also calculated by employing the Monte Carlo code of MCNP-4C,and the nuclear data of Pb isotopes from four libraries:CENDL-3.2,JEFF-3.3,JENDL-5,and ENDF/B-Ⅷ.0 were used individually.By comparing the simulation and experimental results,improvements and deficiencies in the evaluated nuclear data of the Pb isotopes were analyzed.Most of the calculated results were consistent with the experimental results;however,a few areas did not fit well.In the(n,el)energy range,the simulated results from CENDL-3.2 were significantly overestimated;in the(n,inl)D and the(n,inl)C energy regions,the results from CENDL-3.2 and ENDF/B-Ⅷ.0 were significantly overestimated at 120°,and the results from JENDL-5 and JEFF-3.3 are underestimated at 60°in the(n,inl)D energy region.The calculated spectra were analyzed by comparing them with the experimental spectra in terms of the neutron spectrum shape and C/E values.The results indicate that the theoretical simulations,using different data libraries,overestimated or underestimated the measured values in certain energy ranges.Secondary neutron energies and angular distributions in the data files have been presented to explain these discrepancies. 展开更多
关键词 Integral experiment Neutron leakage spectra ^(nat)Pb D-T and D-D neutron sources evaluated nuclear data
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Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data 被引量:3
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作者 Yan-Yan Ding Yang-Bo Nie +9 位作者 Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期145-159,共15页
A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°an... A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight method.The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 cm.The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and JEFF-3.3.Based on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were analyzed.The results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results. 展开更多
关键词 Leakage neutron spectra URANIUM D-T neutron source evaluated nuclear data
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Data credibility evaluation method for formation water in oil and gas fields and its influencing factors
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作者 LI Wei XIE Wuren +2 位作者 WU Saijun SHUAI Yanhua MA Xingzhi 《Petroleum Exploration and Development》 2025年第2期361-376,共16页
The formation water sample in oil and gas fields may be polluted in processes of testing, trial production, collection, storage, transportation and analysis, making the properties of formation water not be reflected t... The formation water sample in oil and gas fields may be polluted in processes of testing, trial production, collection, storage, transportation and analysis, making the properties of formation water not be reflected truly. This paper discusses identification methods and the data credibility evaluation method for formation water in oil and gas fields of petroliferous basins within China. The results of the study show that: (1) the identification methods of formation water include the basic methods of single factors such as physical characteristics, water composition characteristics, water type characteristics, and characteristic coefficients, as well as the comprehensive evaluation method of data credibility proposed on this basis, which mainly relies on the correlation analysis sodium chloride coefficient and desulfurization coefficient and combines geological background evaluation;(2) The basic identifying methods for formation water enable the preliminary identification of hydrochemical data and the preliminary screening of data on site, the proposed comprehensive method realizes the evaluation by classifying the CaCl2-type water into types A-I to A-VI and the NaHCO3-type water into types B-I to B-IV, so that researchers can make in-depth evaluation on the credibility of hydrochemical data and analysis of influencing factors;(3) When the basic methods are used to identify the formation water, the formation water containing anions such as CO_(3)^(2-), OH- and NO_(3)^(-), or the formation water with the sodium chloride coefficient and desulphurization coefficient not matching the geological setting, are all invaded with surface water or polluted by working fluid;(4) When the comprehensive method is used, the data credibility of A-I, A-II, B-I and B-II formation water can be evaluated effectively and accurately only if the geological setting analysis in respect of the factors such as formation environment, sampling conditions, condensate water, acid fluid, leaching of ancient weathering crust, and ancient atmospheric fresh water, is combined, although such formation water is believed with high credibility. 展开更多
关键词 oil and gas field hydrogeology formation water hydrochemical data data credibility evaluation method hydrochemical characteristic indicator influencing factor
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PARE:Privacy-Preserving Data Reliability Evaluation for Spatial Crowdsourcing in Internet of Things
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作者 Peicong He Yang Xin Yixian Yang 《Computers, Materials & Continua》 SCIE EI 2024年第8期3067-3084,共18页
The proliferation of intelligent,connected Internet of Things(IoT)devices facilitates data collection.However,task workers may be reluctant to participate in data collection due to privacy concerns,and task requesters... The proliferation of intelligent,connected Internet of Things(IoT)devices facilitates data collection.However,task workers may be reluctant to participate in data collection due to privacy concerns,and task requesters may be concerned about the validity of the collected data.Hence,it is vital to evaluate the quality of the data collected by the task workers while protecting privacy in spatial crowdsourcing(SC)data collection tasks with IoT.To this end,this paper proposes a privacy-preserving data reliability evaluation for SC in IoT,named PARE.First,we design a data uploading format using blockchain and Paillier homomorphic cryptosystem,providing unchangeable and traceable data while overcoming privacy concerns.Secondly,based on the uploaded data,we propose a method to determine the approximate correct value region without knowing the exact value.Finally,we offer a data filtering mechanism based on the Paillier cryptosystem using this value region.The evaluation and analysis results show that PARE outperforms the existing solution in terms of performance and privacy protection. 展开更多
关键词 Spatial crowdsourcing PRIVACY-PRESERVING data evaluation IOT blockchain
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Study of ADS-B Data Evaluation 被引量:27
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作者 ZHANG Jun LIU Wei ZHU Yanbo 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第4期461-466,共6页
In western China, the terrain and meteorological conditions are so complex that it is not suitable to construct new radar stations. Automatic dependent surveillance-broadcast (ADS-B) is a totally new surveillance me... In western China, the terrain and meteorological conditions are so complex that it is not suitable to construct new radar stations. Automatic dependent surveillance-broadcast (ADS-B) is a totally new surveillance method, so before practically applied and operated in China, abundant tests and evaluations are necessary to validate the performance of ADS-B and guarantee the operational security. During the flight tests, we collect the data of radar, ADS-B and high accuracy position and compare the performance of ADS-B with radar based on high accuracy position. To solve the asynchronous problem among radar data, ADS-B data and real-time kinematic (RTK) data caused by different update rates, this artic.le proposes the technique of synchronizing multi-surveil- lance data by extrapolating from the data of low update rate to high update rate according to velocity and heading. Meanwhile, because radar data, ADS-B data and RTK data are expressed in different coordinates and cannot be compared each other, this article provides a method to unifying the coordinates of multi-surveillance data. By the analysis and evaluation, we can conclude that the performance of ADS-B is better than radar. 展开更多
关键词 civil aviation SURVEILLANCE ADS-B ACCURACY INTEGRITY flight inspection data evaluation
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Quantitative credibility evaluation of Global Energy Interconnection data 被引量:3
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作者 Xinzhi Xu Xingyuan Zhao +3 位作者 Jun Li Yi Gao Ping Yan Fang Chen 《Global Energy Interconnection》 2019年第6期514-521,共8页
The development of Global Energy Interconnection(GEI)is essential for supporting a wide range of basic data resources.The Global Energy Interconnection Development and Cooperation Organization has established a compre... The development of Global Energy Interconnection(GEI)is essential for supporting a wide range of basic data resources.The Global Energy Interconnection Development and Cooperation Organization has established a comprehensive data center covering six major systems.However,methods for accurately describing and scientifically evaluating the credibility of the massive amount of GEI data remain underdeveloped.To address this lack of such methods,a GEI data credibility quantitative evaluation model is proposed here.An evaluation indicator system is established to evaluate data credibility from multiple perspectives and ensure the comprehensiveness and impartiality of evaluation results.The Cloud Model abandons the hard division of comments to ensure objectivity and accuracy in evaluation results.To evaluate the suitability of the proposed method,a case analysis is conducted,wherein the proposed method demonstrates sufficient validity and feasibility. 展开更多
关键词 Global Energy Interconnection data credibility evaluation Cloud Model
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Evaluation of the applicability of climate forecast system reanalysis weather data for hydrologic simulation: A case study in the Bahe River Basin of the Qinling Mountains, China 被引量:6
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作者 胡胜 邱海军 +5 位作者 杨冬冬 曹明明 宋进喜 吴江 黄晨璐 高宇 《Journal of Geographical Sciences》 SCIE CSCD 2017年第5期546-564,共19页
In recent years, global reanalysis weather data has been widely used in hydrological modeling around the world, but the results of simulations vary greatly. To consider the applicability of Climate Forecast System Rea... In recent years, global reanalysis weather data has been widely used in hydrological modeling around the world, but the results of simulations vary greatly. To consider the applicability of Climate Forecast System Reanalysis(CFSR) data in the hydrologic simulation of watersheds, the Bahe River Basin was used as a case study. Two types of weather data(conventional weather data and CFSR weather data) were considered to establish a Soil and Water Assessment Tool(SWAT) model, which was used to simulate runoff from 2001 to 2012 in the basin at annual and monthly scales. The effect of both datasets on the simulation was assessed using regression analysis, Nash-Sutcliffe Efficiency(NSE), and Percent Bias(PBIAS). A CFSR weather data correction method was proposed. The main results were as follows.(1) The CFSR climate data was applicable for hydrologic simulation in the Bahe River Basin(R^2 of the simulated results above 0.50, NSE above 0.33, and |PBIAS| below 14.8. Although the quality of the CFSR weather data is not perfect, it achieved a satisfactory hydrological simulation after rainfall data correction.(2) The simulated streamflow using the CFSR data was higher than the observed streamflow, which was likely because the estimation of daily rainfall data by CFSR weather data resulted in more rainy days and stronger rainfall intensity than was actually observed. Therefore, the data simulated a higher base flow and flood peak discharge in terms of the water balance, except for some individual years.(3) The relation between the CFSR rainfall data(x) and the observed rainfall data(y) could berepresented by a power exponent equation: y=1.4789x0.8875(R2=0.98,P〈0.001). There was a slight variation between the fitted equations for each station. The equation provides a theoretical basis for the correction of CFSR rainfall data. 展开更多
关键词 CFSR weather data hydrologic simulation applicability evaluation SWAT model Bahe River Basin
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Analysis of Evaluation Data Collected on Likert Type Items: Humanities-Courses
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作者 Raghavendra Dwivedi Nagendra Nath Pandey 《Journal of Data Analysis and Information Processing》 2021年第2期102-121,共20页
To improve high quality and/or retain achieved high quality of an academic program, time to time evaluation for quality of each covered course is often an integrated aspect considered in reputed institutions, however,... To improve high quality and/or retain achieved high quality of an academic program, time to time evaluation for quality of each covered course is often an integrated aspect considered in reputed institutions, however, there has been little effort regarding humanities courses. This research article deals with analysis of evaluation data collected regarding humanities course from a College of Commerce & Economics, Mumbai, Maharashtra, India, on Likert type items. Appropriateness of one parametric measure and three non-parametric measures are discussed and used in this regard which could provide useful clues for educational policy planners. Keeping in view of the analytical results using these four measures, regardless of the threshold regarding satisfaction among students, overall performance of almost every subject has been un-satisfactory. There is a need to make a focused approach to take every course at the level of high performance. The inconsistency noticed under every threshold further revealed that under such poorly performing subjects globally, one needs to analyze merely at the global level item. Once the global level analysis reveals high performance of a course, then only item specific analysis may need to be focused to find out the items requiring further improvements. 展开更多
关键词 Evaluation data Humanities Courses Likert Type Items Parametric Measure Non-Parametric Measures
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Use of a Land Surface Model to Evaluate the Observed Soil Moisture of Grassland at the Tongyu Reference Site 被引量:9
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作者 丹利 季劲钧 刘辉志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1073-1084,共12页
A land surface model driven by the continuous three-year observed meteorological data with a time interval of 30 minutes at the Tongyu station, a reference site of the Coordinated Enhanced Observing Period (CEOP), w... A land surface model driven by the continuous three-year observed meteorological data with a time interval of 30 minutes at the Tongyu station, a reference site of the Coordinated Enhanced Observing Period (CEOP), was used to evaluate the observation bias of soil moisture (SM) data and analyze the variation of SM at different time scales. The saline-alkaline soil of the grassland at the Tongyu site makes the measured SM too high, especially in boreal summer of 2003-05. The simulated annual mean SM has the lowest value in 2004 and its three-year variation corresponds to the change of precipitation, whereas the observation shows the increasing trend from 2003 to 2005. Compared to the variation range between -60% and 40% for the anomaly percentage of the simulated daily mean SM during May-October of 2004, the measured data show the higher values more than 40%. The magnitude of the variation trend of the observed daily mean SM in 2003 and 2005 is generally consistent with the simulation. The largest deficiency for the soil moisture observation of the grassland is the overestimated value in the drought year with less precipitation. The simulated monthly mean SM has the lowest value in March due to the large contribution of evaporation relative to precipitation and this phenomenon can not be reproduced in the observation. 展开更多
关键词 soil moisture variation trend Tongyu reference site AVIM data evaluation
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The City Intelligence Quotient (City IQ) Evaluation System" Conception and Evaluation 被引量:8
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作者 Zhiqiang Wu Yunhe Pan +1 位作者 Qiming Ye Lingyu Kong 《Engineering》 SCIE EI 2016年第2期196-211,共16页
After a systematic review of 38 current intelligent city evaluation systems (ICESs) from around the world, this research analyzes the secondary and tertiary indicators of these 38 ICESs from the perspec- tives of sc... After a systematic review of 38 current intelligent city evaluation systems (ICESs) from around the world, this research analyzes the secondary and tertiary indicators of these 38 ICESs from the perspec- tives of scale structuring, approaches and indicator selection, and determines their common base. From this base, the fundamentals of the City Intelligence Quotient (City IOD Evaluation System are developed and five dimensions are selected after a clustering analysis. The basic version, City IQ Evaluation System 1.0, involves 275 experts from 14 high-end research institutions, which include the Chinese Academy of Engineering, the National Academy of Science and Engineering (Germany), the Royal Swedish Academy of Engineering Sciences, the Planning Management Center of the Ministry of Housing and Urban-Rural Development of China, and the Development Research Center of the State Council of China. City IQ Evaluation System 2.0 is further developed, with improvements in its universality, openness, and dy- namic adjustment capability. After employing deviation evaluation methods in the IQ assessment, City IQ Evaluation System 3.0 was conceived. The research team has conducted a repeated assessment of 41 intelligent cities around the world using City IQ Evaluation System 3.0. The results have proved that the City IQ Evaluation System, developed on the basis of intelligent life, features more rational indicators selected from data sources that can offer better universality, openness, and dynamics, and is more sen- sitive and precise. 展开更多
关键词 iCity Evaluation system Open data Intelligent city-being Intelligence quotient
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Discrepancies in boreal summer monsoon rainfall between GPCP and CMAP products during 1979–2014
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作者 HAO Yu-Qian ZHU Cong-Wen LIU Bo-Qi 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第3期226-233,共8页
This study compares the boreal summer monsoon (BSM) precipitation between the GPCP and CMAP products during 1979-2014. The authors apply temporal, spatial correlation and error evaluation methods to evaluate their d... This study compares the boreal summer monsoon (BSM) precipitation between the GPCP and CMAP products during 1979-2014. The authors apply temporal, spatial correlation and error evaluation methods to evaluate their discrepancies in terms of BSM distribution and summer rainfall interannual variability over the five BSM regions. The results suggest that the climatology of the seasonal evolution of BSM rainfall is reflected well in both datasets, and the summer rainfall anomalies of the two products are highly correlated. However, major diversity is found in the rainfall pattern and the magnitude in climatology over the oceanic monsoon areas, especially the western North Pacific monsoon region, as well as in the interannual variability of summer rainfall anomalies over the North Africa and India monsoon regions. Although inconsistency between the two datasets is evident before the 1990s, the use of their arithmetic mean is demonstrated to be an efficient way to reduce the uncertainty between them. 展开更多
关键词 GPCP CMAP boreal summermonsoonl interannualvariability data evaluation
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Using MAN and Coastal AERONET Measurements to Assess the Suitability of MODIS C6.1 Aerosol Optical Depth for Monitoring Changes from Increased Arctic Shipping
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作者 Nicole Mölders Mariel Friberg 《Open Journal of Air Pollution》 2020年第4期77-104,共28页
Collocated data of the moderate resolution imaging spectroradiometer (MO<span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">DIS) Collection 6.1 aerosol o... Collocated data of the moderate resolution imaging spectroradiometer (MO<span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">DIS) Collection 6.1 aerosol optical depths (AOD) at 3 km × 3 km north of 59.9</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">N over ocean were assessed at 550 nm by aerosol robotic network (AERONET) data from coastal sites and marine aerosol network (MAN) data from vessels during June to October 2006 to 2018. Typically, MODIS AOD w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> higher at low and lower at high values than the AERONET AOD. Discrepancies were largest for sites where the Earth’s surface around the site is very heterogeneous (Canadian Archipelago, coast of Greenland). Due to the higher likelihood for sea-ice, MAN and MODIS AOD differed stronger west of Greenland and over the Beaufort Sea than at location in the Greenland and Norwegian Seas and Atlantic. MODIS AOD well captured the inter-seasonal variability found in the AERONET AOD data (R = 0.933). At all sites, MO</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">DIS and AERONET AOD agreement improved as time progressed in the shipping season, hinting at errors in sea-ice vs. open water classification. Overall 75.3% of the MODIS AOD data fell within the limits of the error envelops of the AERONET/MAN AOD data with MAN ranging between 87.5% and 100%. Changes in both MODIS and AERONET mean AOD between two periods of same length (2006-2011, 2013-2018) were explainable by changes in emissions for all sites</span><span style="font-family:Verdana;">.</span> 展开更多
关键词 Aerosol Optical Depth over the Arctic Ocean MODIS Evaluation by AERONET and MAN data Changes in Arctic Aerosol Optical Depth over the Ocean North of 59.9°N Arctic Shipping Season Aerosol Optical Depths
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The AME2012 atomic mass evaluation(Ⅰ).Evaluation of input data,adjustment procedures 被引量:19
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作者 G.Audi M.Wang +4 位作者 A.H.Wapstra F.G.Kondev M.MacCormick X.Xu B.Pfeiffer 《Chinese Physics C》 SCIE CAS CSCD 2012年第12期1603-2014,共412页
This paper is the second part of the new evaluation of atomic masses, AME2012. From the results of a leastsquares calculation, described in Part I, for all accepted experimental data, we derive here tables and graphs ... This paper is the second part of the new evaluation of atomic masses, AME2012. From the results of a leastsquares calculation, described in Part I, for all accepted experimental data, we derive here tables and graphs to replace those of AME2003. The first table lists atomic masses. It is followed by a table of the influences of data on primary nuclides, a table of separation energies and reaction energies, and finally, a series of graphs of separation and decay energies. The last section in this paper lists all references to the input data used in Part I of this AME2012 and also to the data included in the NUBASE2012 evaluation (first paper in this issue). 展开更多
关键词 AME The AME2012 atomic mass evaluation Evaluation of input data adjustment procedures data
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Evaluation of FY-3B Reprocessed OLR Data in the Asian–Australian Monsoon Region during 2011–2019:Comparison with NOAA OLR 被引量:2
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作者 Lin LIU Wanchun ZHANG +2 位作者 Wen CHEN Renguang WU Lin WANG 《Journal of Meteorological Research》 SCIE CSCD 2021年第6期964-974,共11页
The present study evaluates spatial and temporal characteristics of the Fengyun-3 B(FY-3 B)’s outgoing longwave radiation(OLR)data based on NOAA OLR data and the GPCP(Global Precipitation Climatology Project)precipit... The present study evaluates spatial and temporal characteristics of the Fengyun-3 B(FY-3 B)’s outgoing longwave radiation(OLR)data based on NOAA OLR data and the GPCP(Global Precipitation Climatology Project)precipitation data over the Asian-Australian region during 2011-2019.In terms of climatological distribution patterns and interannual standard deviation,FY-3 BOLR are quite consistent with NOAA OLR,with annual and seasonal pattern correlation coefficients all exceeding 0.93.There are some discrepancies in the OLR magnitude between FY-3 B and NOAA,especially for the OLR climatology;the climatological OLR from FY-3 B are systematically larger than those from NOAA over the whole study region.In addition,examination of the temporal correlation coefficients between OLR and precipitation over the Asian-Australian monsoon(AAM)region reveals that both of the OLR datasets have captured the widespread negative correlation with precipitation,and FY-3 BOLR exhibits a stronger relationship to precipitation over land.Moreover,FY-3 BOLR exhibits better responses to the precipitation anomalies over India during the extreme El Nino and La Nina events.These results suggest that the FY-3 B OLR dataset is of high quality and worthy of further global application. 展开更多
关键词 Fengyun-3B outgoing longwave radiation precipitation Asian–Australian monsoon data evaluation
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A decentralized data evaluation framework in federated learning 被引量:1
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作者 Laveen Bhatia Saeed Samet 《Blockchain(Research and Applications)》 EI 2023年第4期14-23,共10页
Federated Learning(FL)is a type of distributed deep learning framework in which multiple devices train a local model using local data,and the gradients of the local model are then sent to a central server that aggrega... Federated Learning(FL)is a type of distributed deep learning framework in which multiple devices train a local model using local data,and the gradients of the local model are then sent to a central server that aggregates them to create a global model.This type of framework is ideal where data privacy is of utmost importance because the data never leave the local device.However,a major concern in FL is ensuring the data quality of local training data.Since there is no control over the local training data,ensuring that the local model is trained on clean data becomes challenging.A model trained on poor-quality data can have a significant impact on its accuracy.In this paper,we propose a decentralized approach using blockchain to ensure local model data quality.We use miners to validate each local model by checking its accuracy against a secret testing dataset.This is done using a smart contract that the miners invoke during the mining process.The local model is aggregated with the global model only if it passes a preset accuracy threshold.We test our proposed method on two datasets:the Brain Tumor Classification dataset from Kaggle,comprised of 7000 MRI images divided into two classes(Tumor/No Tumor),and the Medical MNIST dataset,which includes 58,954 images classified into six different classes:AbdomenCT,BreastMRI,ChestCT,Chest X-ray,Hand X-ray,and HeadCT.Our results show that our method outperforms the original FL approach in all experiments. 展开更多
关键词 Federated learning Blockchain Decentralized federated learning Decentralized data evaluation Smart contracts
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Evaluation of the Madden–Julian Oscillation in Fengyun-3B Polar-Orbiting Satellite Reprocessed OLR Data
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作者 Hainan GONG Wanchun ZHANG +5 位作者 Ling SUN Zizhen DONG Peng ZHANG Lin WANG Wen CHEN Renguang WU 《Journal of Meteorological Research》 SCIE CSCD 2022年第6期931-946,共16页
The present study compares the spatial and temporal characteristics of the Madden-Julian Oscillation(MJO)in Fengyun-3B(FY-3B)polar-orbiting satellite reprocessed outgoing longwave radiation(OLR)data and NOAA OLR data ... The present study compares the spatial and temporal characteristics of the Madden-Julian Oscillation(MJO)in Fengyun-3B(FY-3B)polar-orbiting satellite reprocessed outgoing longwave radiation(OLR)data and NOAA OLR data during 2011-2020.The spatial distributions of climatological mean and intraseasonal standard deviation of FY-3B OLR during boreal winter(November-April)and boreal summer(May-October)are highly consistent with those of NOAA OLR.The FY-3B and NOAA OLRs display highly consistent features in the wavenumber-frequency spectra,the occurrence frequency of MJO active days,the eastward propagation of MJO along the equator,and the interannual variability of MJO according to diagnoses using the all-season multivariate EOF analysis.These results indicate that the FY-3B OLR produced by the polar-orbiting satellites is of high quality and worthy of global application. 展开更多
关键词 Fengyun-3B outgoing longwave radiation Madden–Julian Oscillation multivariate empirical orthogonal function data evaluation
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Benchmark experiment system for^(252)Cf spontaneous fission source usingγtagging
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作者 Yu-Ting Wei Chang-Lin Lan +11 位作者 Bo Gao Xian-Lin Yang Gong Jiang Jia-Hao Wang Bo Xie Yang-Bo Nie Yan-Liang Chang Ge Zhang Fan Wu Kuo-Zhi Xu Shi-Long Liu Xi-Chao Ruan 《Nuclear Science and Techniques》 2025年第11期221-231,共11页
Benchmark experiments are indispensable for the development of neutron nuclear data evaluation libraries.Given the lack of domestic benchmarking of nuclear data in the fission energy region,this study developed a neut... Benchmark experiments are indispensable for the development of neutron nuclear data evaluation libraries.Given the lack of domestic benchmarking of nuclear data in the fission energy region,this study developed a neutron leakage spectrum measurement system using a spherical sample based on the^(252)Cf spontaneous fission source.The EJ309 detector(for highenergy measurements)and CLYC detector(for low-energy measurements)were combined to measure the time-of-flight spectrum using theγtagging method.To assess the performance of the system,the time-of-flight spectrum without a sample was measured first.The experimental spectra were consistent with those simulated using the Monte Carlo method and the standard^(252)Cf spectrum from ISO:8529-1.This demonstrates that the system can effectively measure the neutron events in the 0.15-8.0 MeV range.Then,a spherical polyethylene sample was used as the standard to verify the accuracy of the system for the benchmark experiment.The simulation results were obtained using the Monte Carlo method with evaluated data from the ENDF/B-Ⅷ.0,CENDL-3.2,JEFF-3.3,and JENDL-5 libraries.The measured neutron leakage spectra were compared with the corresponding simulated results for the neutron spectrum shape and calculated C/E values.The results showed that the simulated spectra with different data libraries reproduced the experimental results well in the 0.15-8.0 MeV range.This study confirms that the leakage neutron spectrum measurement system based on the^(252)Cf source can perform benchmarking and provides a foundation for evaluating neutron nuclear data through benchmark experiments. 展开更多
关键词 ^(252)Cf Neutron leakage spectrum Benchmark experiment Time-of-flight technique evaluated nuclear data Spherical samples
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A shielding integral experiment with different thickness of slab^(9)Be samples based on deuterium-tritium neutron source
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作者 Shi-Yu Zhang Yang-Bo Nie +10 位作者 Qi Zhao Xin-Yi Pan Yan-Yan Ding Kuo-Zhi Xu Xiao-Yu Wang Bei-Bo He Qi Sun Jie Ren Hong-Tao Chen Xi-Chao Ruan Zheng Wei 《Nuclear Science and Techniques》 2025年第11期327-345,共19页
Beryllium(^(9)Be)serves as a crucial neutron multiplier and reflection material,being extensively employed in the nuclear industry.The evaluated nuclear data are utilized in the design of the nuclear devices.Following... Beryllium(^(9)Be)serves as a crucial neutron multiplier and reflection material,being extensively employed in the nuclear industry.The evaluated nuclear data are utilized in the design of the nuclear devices.Following the interaction between neutrons and^(9)Be,all neutrons generated stem from the^(9)Be(n,2n)^(8)Be reaction channel,except for the elastic scattering reaction channel.Nevertheless,the data of the outgoing neutron double differential cross section of the reaction channel provided by the latest internationally evaluated libraries still exhibit considerable discrepancies.A shielding integral experiment based on slab^(9)Be samples with measurements of neutron spectra leaked from different angles is an effective approach to verify the double differential cross-section data.Hence,in this study,a shielding integral experiment of^(9)Be samples of different thicknesses was conducted using a nanosecond pulsed deuterium-tritium neutron source established by the China Institute of Atomic Energy.The neutron time-of-flight spectra of three thicknesses(4.4 cm,8.8 cm,and 13.2 cm)and six angles(47°,58°,73°,107°,122°,and 133°)were measured by the neutron time-of-flight method,and 18 sets of experimental data were obtained.Additionally,the MCNP-4C program was used to obtain the simulated results of the leakage neutron spectra using the evaluated nuclear data of^(9)Be from the CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5,and JEFF-3.3 libraries.The simulated results of the leakage neutron spectra were compared with the experimental results,and the results showed that in the elastic scattering energy region,the simulated results from the CENDL-3.2,ENDF/B-Ⅷ.0,and JENDL-5 libraries were slightly higher at small angles and slightly lower at large angles.In the(n,2n)energy region,the simulated results from the CENDL-3.2 library were significantly different from the experimental results in terms of spectral shape,and the simulated results from the ENDF/B-Ⅷ.0 and the JENDL-5 libraries were in good agreement with the experimental results at small angles but low at large angles.The simulated results from the JEFF-3.3 library showed serious underestimation at all angles. 展开更多
关键词 Beryllium evaluated nuclear data Shielding integral experiment Deuterium tritium neutron source Neutron time-of flight spectrum MCNP-4C program
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Evaluation of Human Settlement Quality of Nyingchi City,Southeastern Qinghai-Tibet Plateau,China
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作者 LIN Feng XIN Zhongbao +1 位作者 RAN Lishan QIAN Junxi 《Chinese Geographical Science》 2025年第6期1456-1472,共17页
The construction of human settlements plays a vital role in achieving sustainable development goals.With the growing population,both urban and rural planning—as well as the development of human settlements—on the Qi... The construction of human settlements plays a vital role in achieving sustainable development goals.With the growing population,both urban and rural planning—as well as the development of human settlements—on the Qinghai-Tibet Plateau in China have received increasing attention.This study proposed a comprehensive framework to assess the quality of human settlements and identify their limiting factors of Nyingchi City,southeastern Qinghai-Tibet Plateau of China.The framework integrated a region-specific evaluation system tailored to the plateau’s unique characteristics and utilized multi-source data collected through field-based questionnaires and remote sensing.Analytical methods employed include the Criteria Importance Through Intercriteria Correlation(CRITIC)weighting method,difference analysis for evaluating spatial and categorical variations,and a novel approach introduced in this study for identifying limiting factors.In August 2021,a questionnaire-based survey was conducted in the southeastern Qinghai-Tibet Plateau,yielding 823 valid responses.The average evaluation score for human settlement quality(HSQ)was(6.96±0.94),indicating that settlement conditions were approaching the satisfaction threshold.Notably,the score for the health dimension was(6.28±1.41),reflecting relatively underdeveloped health services in the region.From the perspective of spatial patterns,despite its favorable natural conditions,the HSQ in Medog County was relatively backward,reflecting uncoordinated development that warrants attention.Significant differences were observed in the perceptions of human settlements among different groups in terms of ethnicity,income,and educational background.Low ratings for income and employment conditions represented a major limitation to the local HSQ.The development of human settlements in the southeastern Qinghai-Tibet Plateau still needs further promotion due to population disparities and the challenges of creating a healthy environment in high-altitude regions.The results are valuable for improving human settlements in plateau regions,which can help make targeted policy recommendations. 展开更多
关键词 human settlement quality(HSQ) questionnaire survey criteria importance through intercriteria correlation(CRITIC)weight method multisource data evaluation Nyingchi City Qinghai-Tibet Plateau China
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Cross-sectional rainfall observation on the central-western Tibetan Plateau in the warm season:System design and preliminary results 被引量:2
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作者 Kun YANG Yingying CHEN +20 位作者 Lazhu Changhui ZHAN Xiaoyan LING Xu ZHOU Yaozhi JIANG Xiangnan YAO Hui LU Xiaogang MA Lin OUYANG Weihao PAN Yanghang REN Changkun SHAO Jiaxin TIAN Yan WANG Hua YANG Siyu YUE Ke ZHANG Dingchi ZHAO Long ZHAO Jianhong ZHOU Mijun ZOU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第5期1015-1030,共16页
The central and western Tibetan Plateau(CWTP)is characterized by harsh environment and strong interactions among the spheres of earth as well as significant changes in climate and water cycles over the past four decad... The central and western Tibetan Plateau(CWTP)is characterized by harsh environment and strong interactions among the spheres of earth as well as significant changes in climate and water cycles over the past four decades.The lack of precipitation observations is a bottleneck for the study of land surface processes in this region.Over the past six years,we have designed and established two observation transects across the south-north and the west-east in this region to obtain hourly rainfall data during the warm season(May-September).The south-north transect extends from Yadong Valley on the southern slope of the Himalayas to Shuanghu County in the hinterland of the plateau,with a total of 31stations;the west-east transect extends from Shiquanhe in the west to Naqu in the central TP,with a total of 22 stations.The observation dataset has been applied to clarify the spatiotemporal characteristics of precipitation in the CWTP,to evaluate the quality of typical gridded precipitation products,to support the development of regional climate models,and to reveal the processes of summertime lake-air interactions.The observation dataset has been released in the National Tibetan Plateau Data Center. 展开更多
关键词 Central and western Tibetan Plateau Rainfall observation transects Observation uncertainty Spatiotemporal characteristics of precipitation Precipitation data evaluation
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