期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
基于Logistic回归的古代玻璃制品化学成分分析和研究
1
作者 孙浩东 《电脑迷》 2023年第1期19-21,共3页
文章主要通过研究玻璃含有的不同化学成分,分析和鉴别古代的玻璃制品。首先分析了现有玻璃文物的数据,利用Spearman’s rank correlation coefficient和卡方检验表面分化、纹饰、颜色和玻璃类型之间的联系,采用Logistic回归鉴别未知文物... 文章主要通过研究玻璃含有的不同化学成分,分析和鉴别古代的玻璃制品。首先分析了现有玻璃文物的数据,利用Spearman’s rank correlation coefficient和卡方检验表面分化、纹饰、颜色和玻璃类型之间的联系,采用Logistic回归鉴别未知文物,分析其所属的类型,并分析了分类结果的灵敏度。通过分析可知,文章采用的分类方法,能较好地通过化学成分对玻璃进行分类。 展开更多
关键词 spearmans rank correlation coefficient 卡方检验 LOGIsTIC回归
下载PDF
Change Trend of Chinese Urban Residents' Food-nitrogen Consumption 被引量:2
2
作者 王俊能 许振成 彭晓春 《Agricultural Science & Technology》 CAS 2010年第4期176-179,共4页
Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen ... Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen consumption during the China's urbanization process.Results showed that after 1980s,the annual consumption of Chinese urban residents' food-nitrogen had a change trend of " increase-decrease-increase" and generally presented as a slight increasing trend;With the acceleration of rapid economic development and urbanization process,Chinese urban residents' food-nitrogen consumption will still keep a rising trend in future,and also has a large rising space. 展开更多
关键词 Food consumption NITROGEN spearmans rank correlation coefficient ARIMA model Urban residents China
下载PDF
Characteristics of Ambient Air Quality in the Central Urban Area of Western Guizhou in the Past Five Years 被引量:1
3
作者 Shihua JIANG Zaixiang CHI +3 位作者 Kai XU Lijuan LIU Zijiang YANG Changwen CHEN 《Meteorological and Environmental Research》 CAS 2020年第6期23-30,共8页
Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become... Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become one of the main problems that endanger human health and restrict economic development,which has been widely concerned.In this paper,the air quality status and its changing trend were analyzed by using the methods of the comprehensive index of ambient air quality and Spearman s rank correlation coefficient,based on the hourly pollutant concentration data of five national ambient air quality monitoring stations in the central urban area of Liupanshui City,Guizhou Province from January 1,2015 to December 31,2019.The results showed that the concentration of air pollutants in the atmosphere in the past five years showed a downward trend in the central urban area of Liupanshui City.During 2018-2019,the air quality has been up to the standard for two consecutive years,and it was developing to a higher quality direction.The air quality was better in summer half year than in winter half year.In one year,the air quality was the best in June and the worst in February.The air quality was the best at 07:00 and the worst at 21:00 every day.The air quality in the east and the west of the city was better than that in the middle.In most years,the activities,making and burning paper to resemble money as an offering sacrifices to gods or ancestors in Zhongyuan Festival,caused serious pollution. 展开更多
关键词 Air quality Pollution concentration spearman s rank correlation coefficient Change trends
下载PDF
An Automatic Monitoring and Alarming Method for the Power Supply of Weather Radars
4
作者 Shihua JIANG Ruyong LONG +3 位作者 Changwen CHEN Lijuan LIU Kun ZHAO Liang HOU 《Meteorological and Environmental Research》 CAS 2021年第2期23-25,29,共4页
As weather radar stations require headroom environment to operate,they were mostly built on highlands which are usually unattended.The mains supply is relatively poor,and the risk of radar stoppages due to power outag... As weather radar stations require headroom environment to operate,they were mostly built on highlands which are usually unattended.The mains supply is relatively poor,and the risk of radar stoppages due to power outage is therefore ever-present.As such,the radar construction program is used to build a complementary security video monitoring system.By collecting monitoring images of the regulated power supply in real-time from power supply auto transfer systems in distribution rooms and radar transceiver rooms,using Spearman’s rank correlation coefficient to analyse pixel variation trends,and supplementing statistical analysis of pixel characteristics difference to eliminate misjudgments resulting from low image contrast in special scenarios,a software can be developed through C#.It has the function of automatically monitoring mains supply and alerting staff on duty to handle the power outage in a timely manner via text message so that any potential risk is neutralised before it can cause damage.This monitoring and auto-alerting approach is generally applicable to unattended rooms with large amounts of electronical equipment. 展开更多
关键词 Weather radar spearmans rank correlation coefficient Power supply MONITOR ALARM
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部