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A Survey of Error Analysis and Calibration Methods for MEMS Triaxial Accelerometers
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作者 Bo Xiao Yinghang Jiang +2 位作者 Qi Liu Xiaodong Liu Mingxu Sun 《Computers, Materials & Continua》 SCIE EI 2020年第7期389-399,共11页
MEMS accelerometers are widely used in various fields due to their small size and low cost,and have good application prospects.However,the low accuracy limits its range of applications.To ensure data accuracy and safe... MEMS accelerometers are widely used in various fields due to their small size and low cost,and have good application prospects.However,the low accuracy limits its range of applications.To ensure data accuracy and safety we need to calibrate MEMS accelerometers.Many authors have improved accelerometer accuracy by calculating calibration parameters,and a large number of published calibration methods have been confusing.In this context,this paper introduces these techniques and methods,analyzes and summarizes the main error models and calibration procedures,and provides useful suggestions.Finally,the content of the accelerometer calibration method needs to be overcome. 展开更多
关键词 MEMS ACCELEROMETER CALIBRATION error analysis accelerometer calibration
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Changes in air pollutants during the COVID-19 lockdown in Beijing:Insights from a machine-learning technique and implications for future control policy 被引量:2
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作者 Jiabao Hu Yuepeng Pan +4 位作者 Yuexin He Xiyuan Chi Qianqian Zhang Tao Song Weishou Shen 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第4期63-69,共7页
基于2015–2020年北京35个环境空气站和20个气象站观测资料,应用机器学习方法(随机森林算法)分离了气象条件和源排放对大气污染物浓度的影响.结果发现,为应对疫情采取的隔离措施使北京2020年春节期间大气污染物浓度降低了35.1%–51.8%;... 基于2015–2020年北京35个环境空气站和20个气象站观测资料,应用机器学习方法(随机森林算法)分离了气象条件和源排放对大气污染物浓度的影响.结果发现,为应对疫情采取的隔离措施使北京2020年春节期间大气污染物浓度降低了35.1%–51.8%;其中,背景站氮氧化物和一氧化碳浓度的降幅最大,超过了以往报道较多的交通站点.同时,2020年春节期间的气象条件不利于污染物扩散,导致多次霾污染事件发生.为进一步改善北京空气质量,未来需要优化减排策略. 展开更多
关键词 机器学习 大气污染 去气象化 COVID-19 减排策略
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江苏省2000–2017年农业源氨气排放年际趋势估算 被引量:3
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作者 HUANG Jiayu XIONG Ruonan +2 位作者 FANG Li LI Tianling SHEN Weishou 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第3期268-273,共6页
氨气是大气中的微量碱性气体,可以与酸性气体二氧化硫和氮氧化物的氧化产物发生化学反应,生成硫酸铵和硝酸铵等二次颗粒物。大量氨存在会加速细颗粒物的生成速率,在霾污染的形成过程中具有重要作用。畜禽养殖和氮肥施用是氨排放清单中... 氨气是大气中的微量碱性气体,可以与酸性气体二氧化硫和氮氧化物的氧化产物发生化学反应,生成硫酸铵和硝酸铵等二次颗粒物。大量氨存在会加速细颗粒物的生成速率,在霾污染的形成过程中具有重要作用。畜禽养殖和氮肥施用是氨排放清单中最主要的两个排放源。江苏省农业源氨排放量居于国家大气污染防治重点区域各省市第一。本文利用排放因子法对2000–2017年江苏省农业源氨排放进行了估算,研究江苏省18年来氨排放的特征及变化趋势。结果表明,2000–2017年江苏省农业源氨排放平均78.08%来源于畜禽养殖, 21.92%来源于氮肥施用,并且排放趋势呈现波动式变化。2000–2012年氨排放呈现先降低后增加的趋势, 2007年出现最小氨排放为708.76 kt yr-1, 2012年出现最大氨排放为837.64 kt yr-1。2012–2017年呈现下降趋势, 2017年农业源氨排放为690.64 kt yr-1。本文对年际变化趋势进行了详细的估计,并提出了可能的应对措施,将为江苏省开展氨气排放控制提供科学基础。 展开更多
关键词 农业源 氨气排放 畜禽养殖 氮肥施用
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SMK-means:An Improved Mini Batch K-means Algorithm Based on Mapreduce with Big Data 被引量:1
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作者 Bo Xiao Zhen Wang +1 位作者 Qi Liu Xiaodong Liu 《Computers, Materials & Continua》 SCIE EI 2018年第9期365-379,共15页
In recent years,the rapid development of big data technology has also been favored by more and more scholars.Massive data storage and calculation problems have also been solved.At the same time,outlier detection probl... In recent years,the rapid development of big data technology has also been favored by more and more scholars.Massive data storage and calculation problems have also been solved.At the same time,outlier detection problems in mass data have also come along with it.Therefore,more research work has been devoted to the problem of outlier detection in big data.However,the existing available methods have high computation time,the improved algorithm of outlier detection is presented,which has higher performance to detect outlier.In this paper,an improved algorithm is proposed.The SMK-means is a fusion algorithm which is achieved by Mini Batch K-means based on simulated annealing algorithm for anomalous detection of massive household electricity data,which can give the number of clusters and reduce the number of iterations and improve the accuracy of clustering.In this paper,several experiments are performed to compare and analyze multiple performances of the algorithm.Through analysis,we know that the proposed algorithm is superior to the existing algorithms. 展开更多
关键词 BIG data OUTLIER detection SMK-means MINI BATCH K-MEANS simulated annealing
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