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The Application of Pearson Correlational Analysis Method in Air Quality Analysis of Beijing-Tianjin-Hebei Region 被引量:15
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作者 杨宁 冀德刚 李双金 《Agricultural Science & Technology》 CAS 2015年第3期590-592,共3页
Based on the analysis of monitoring data on six pollution indexes of SO2, NO2, CO, O3, PM10 and PM2.5 from 53 monitoring points in 7 cities, including Beijing, Tianjin, Shijiazhuang, etc., from April 8 of 2014 to July... Based on the analysis of monitoring data on six pollution indexes of SO2, NO2, CO, O3, PM10 and PM2.5 from 53 monitoring points in 7 cities, including Beijing, Tianjin, Shijiazhuang, etc., from April 8 of 2014 to July 23 of 2014, this article adopted Pearson correlation coefficient method to determine the relevance among each pollutant of these cities with the help of SPSS. The results showed that such three leading indexes as SO2, PM10 and PM2.5 had strong correlation in Beijing, Tianjin and main cities of Hebei. Finally, some suggestions and preventive measures for the cooperative governance of air pollution in Beijing-Tianjin-Hebei Region were put forward, hoping this can help them. 展开更多
关键词 Pearson Correlation coefficient Linear interpolation Monitoring indicators Air quality
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用于激光吸收光谱二维重建的光谱优化选择方法研究
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作者 辛明原 宋俊玲 +2 位作者 饶伟 洪延姬 姜雅晶 《推进技术》 EI CAS CSCD 北大核心 2020年第10期2332-2340,共9页
光谱组合对多光谱重建技术的重建结果有很大影响,不合理的光谱组合会降低光谱测量的有效性,加大重建误差。为了从海量的光谱数据库中选出适用于被测流场参数范围的最优光谱组合,提出了一种基于向量组线性相关性的光谱选择方法,采用数值... 光谱组合对多光谱重建技术的重建结果有很大影响,不合理的光谱组合会降低光谱测量的有效性,加大重建误差。为了从海量的光谱数据库中选出适用于被测流场参数范围的最优光谱组合,提出了一种基于向量组线性相关性的光谱选择方法,采用数值仿真的方法开展研究,仿真结果验证了方法的可行性与可靠性。分析了测量信号无噪声和存在噪声时,光谱数量与重建结果的关系。研究发现最优光谱组合的线性相关指数小于0.01时,该组合存在光谱的冗余。保证测量有效性的同时光谱数量最少的光谱组合为线性相关指数不小于0.01的最优光谱组合。测量存在噪声时,光谱数量越多,噪声的抑制效果越好,重建结果精度更高。通过重复测量法可以有效降低噪声影响,用最少数量的光谱实现更多光谱的测量效果。 展开更多
关键词 激光吸收光谱 多光谱重建 线性相关指数 光谱选择 光谱数量
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Economical Analysis of Milk Production in the Farms of Siedlce Region
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作者 Sosnowski Jacek Jankowski Kazimierz Truba Milena Kaczorek Anna Krol Justyna Romanczuk Tadeusz Kolczarek Roman 《Journal of Life Sciences》 2014年第7期626-631,共6页
Last years the most profitable line of activity in agriculture is considered with milk production. The-effectiveness of this project depends primarily on the direct costs and the obtained of purchase price. Therefore ... Last years the most profitable line of activity in agriculture is considered with milk production. The-effectiveness of this project depends primarily on the direct costs and the obtained of purchase price. Therefore the aim of this work was to analyze the financial results of dairy farms in the east part of Mazovia region. Completing the research in 2010, to the owners of 36 farms were sent a questionnaire containing 18 questions. The obtained data were used to characterize the various research facilities. And then the whole population was devoted on the 6 production groups, depend on the number of physical units of dairy cows. Moreover, based on survey data, an analysis of the profitability of milk production was done. It was the following economic values: direct costs, revenue, gross margin and the index of production profitability. Also the statistical analysis by calculating the Pearson linear correlation coefficient (r) and coefficient of determination (R2) was done. The study showed that the highest annual yield of milk from a cow at the level of 7500 kg, reached the farmers with the area of l 9.7 ha of with the density of 1.82 BFU/ha and with 8 years of cow utilization. Respondents from this group also received the highest value of effectiveness index (184.60%). In addition, the performed regression analysis showed significant positive correlation between the effectiveness index and the surface agricultural lands occurring in the farms, density of agricultural lands, and efficiency from a cow and the price of milk. 展开更多
关键词 Milk production effectiveness index direct costs economical analysis.
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