Foreign-made clocks and watches began to be exported to China in the 17th century. During the Qing Dynasty (1644-1911), the imperial court imported tens of thousands of clocks and watches. At the Palace Museum in Beij...Foreign-made clocks and watches began to be exported to China in the 17th century. During the Qing Dynasty (1644-1911), the imperial court imported tens of thousands of clocks and watches. At the Palace Museum in Beijing, about 200 timepieces collected by the imperial court are still on display in the clock and watch exhibition hall. They were made in Britain, France, Switzerland and Japan. Many foreign presidents and展开更多
以“中国制造2025”战略为背景,研究中国经济增长对外贸的依赖程度.选取1978—2018年进出口贸易量和GDP为基础数据,分别运用NARX(nonlinear autoregressive with exogenous inputs)动态神经网络和ARIMA(autoregressive integrated movin...以“中国制造2025”战略为背景,研究中国经济增长对外贸的依赖程度.选取1978—2018年进出口贸易量和GDP为基础数据,分别运用NARX(nonlinear autoregressive with exogenous inputs)动态神经网络和ARIMA(autoregressive integrated moving average model)模型作为单项预测,建立组合预测模型,预测了2019—2025年中国经济对外贸易依存度,并对其进行测度和分析.研究结果表明:组合预测模型比两种单项预测模型效果更好,预测精度更高;未来几年中国的对外贸易依存度指数值呈下降趋势,预计2025年将下降到0.2279,同比2019年下降幅度高达26.83%.展开更多
文摘Foreign-made clocks and watches began to be exported to China in the 17th century. During the Qing Dynasty (1644-1911), the imperial court imported tens of thousands of clocks and watches. At the Palace Museum in Beijing, about 200 timepieces collected by the imperial court are still on display in the clock and watch exhibition hall. They were made in Britain, France, Switzerland and Japan. Many foreign presidents and
文摘以“中国制造2025”战略为背景,研究中国经济增长对外贸的依赖程度.选取1978—2018年进出口贸易量和GDP为基础数据,分别运用NARX(nonlinear autoregressive with exogenous inputs)动态神经网络和ARIMA(autoregressive integrated moving average model)模型作为单项预测,建立组合预测模型,预测了2019—2025年中国经济对外贸易依存度,并对其进行测度和分析.研究结果表明:组合预测模型比两种单项预测模型效果更好,预测精度更高;未来几年中国的对外贸易依存度指数值呈下降趋势,预计2025年将下降到0.2279,同比2019年下降幅度高达26.83%.
