Based on panel data such as 2009-2018 R&D expenditures,full-time equivalent of R&D personnel,Number of valid invention patents,and technology market turnover in China's Shanghai,Jiangsu,Zhejiang,and Anhui ...Based on panel data such as 2009-2018 R&D expenditures,full-time equivalent of R&D personnel,Number of valid invention patents,and technology market turnover in China's Shanghai,Jiangsu,Zhejiang,and Anhui provinces(cities),using Griliches-Jaffe knowledge to produce Function,construct Time fixed effects model,conduct empirical research on the main factors affecting the technological innovation capability of the Yangtze River Delta,focusing on the relationship between the technological market and technological innovation capability.The results show that human capital and R&D expenditures have a significant and positive impact on the technological innovation capacity of the Yangtze River Delta.Although the technology market has a positive effect on the scientific and technological innovation capacity of the Yangtze River Delta,the effect is not significant.Propose countermeasures and suggestions to strengthen the influence of the technology market on technological innovation.展开更多
We present a diode-pumped high-energy ceramic Nd：YAG planar waveguide that is demonstrated as a record in output energy for the ceramic planar waveguide fabricated by nonaqueous tape casting and solid-state reactive ...We present a diode-pumped high-energy ceramic Nd：YAG planar waveguide that is demonstrated as a record in output energy for the ceramic planar waveguide fabricated by nonaqueous tape casting and solid-state reactive sintering. Under a repetition rate of 100 Hz and a pulse width of 250 μs, a maximum output pulse energy of 327 mJ is obtained with a beam quality factor of = 2.6 × 7.0. The corresponding peak power is 1308 W. The extraction efficiency of the system is about 56%.展开更多
We present an uncertainty analysis of ecological process parameters and CO_(2)flux components(Reco,NEE and gross ecosystem exchange(GEE))derived from 3 years’continuous eddy covariance meas-urements of CO_(2)fluxes a...We present an uncertainty analysis of ecological process parameters and CO_(2)flux components(Reco,NEE and gross ecosystem exchange(GEE))derived from 3 years’continuous eddy covariance meas-urements of CO_(2)fluxes at subtropical evergreen coniferous plantation,Qianyanzhou of ChinaFlux.Daily-differencing approach was used to analyze the random error of CO_(2)fluxes measurements and bootstrapping method was used to quantify the uncertainties of three CO_(2)flux components.In addition,we evaluated different models and optimization methods in influencing estimation of key parameters and CO_(2)flux components.The results show that:(1)Random flux error more closely follows a dou-ble-exponential(Laplace),rather than a normal(Gaussian)distribution.(2)Different optimization meth-ods result in different estimates of model parameters.Uncertainties of parameters estimated by the maximum likelihood estimation(MLE)are lower than those derived from ordinary least square method(OLS).(3)The differences between simulated Reco,NEE and GEE derived from MLE and those derived from OLS are 12.18%(176 g C·m-2·a-1),34.33%(79 g C·m-2·a-1)and 5.4%(92 g C·m-2·a-1).However,for a given parameter optimization method,a temperature-dependent model(T_model)and the models derived from a temperature and water-dependent model(TW_model)are 1.31%(17.8 g C·m-2·a-1),2.1%(5.7 g C·m-2·a-1),and 0.26%(4.3 g C·m-2·a-1),respectively,which suggested that the optimization methods are more important than the ecological models in influencing uncertainty in estimated carbon fluxes.(4)The relative uncertainty of CO_(2)flux derived from OLS is higher than that from MLE,and the uncertainty is related to timescale,that is,the larger the timescale,the smaller the uncertainty.The relative uncertainties of Reco,NEE and GEE are 4%-8%,7%-22%and 2%-4%respectively at annual timescale.展开更多
文摘Based on panel data such as 2009-2018 R&D expenditures,full-time equivalent of R&D personnel,Number of valid invention patents,and technology market turnover in China's Shanghai,Jiangsu,Zhejiang,and Anhui provinces(cities),using Griliches-Jaffe knowledge to produce Function,construct Time fixed effects model,conduct empirical research on the main factors affecting the technological innovation capability of the Yangtze River Delta,focusing on the relationship between the technological market and technological innovation capability.The results show that human capital and R&D expenditures have a significant and positive impact on the technological innovation capacity of the Yangtze River Delta.Although the technology market has a positive effect on the scientific and technological innovation capacity of the Yangtze River Delta,the effect is not significant.Propose countermeasures and suggestions to strengthen the influence of the technology market on technological innovation.
基金supported by the Key Laboratory of Science and Technology on High Energy Lasers(China Academy of Engineering Physics)
文摘We present a diode-pumped high-energy ceramic Nd：YAG planar waveguide that is demonstrated as a record in output energy for the ceramic planar waveguide fabricated by nonaqueous tape casting and solid-state reactive sintering. Under a repetition rate of 100 Hz and a pulse width of 250 μs, a maximum output pulse energy of 327 mJ is obtained with a beam quality factor of = 2.6 × 7.0. The corresponding peak power is 1308 W. The extraction efficiency of the system is about 56%.
基金Supported by National Natural Science Foundation of China(Grant No.30570347)Innovative Research International Partnership Project of the Chinese Academy of Sciences(Grant No.CXTD-Z2005-1)National Basic Research Program of China(Grant No.2002CB412502)
文摘We present an uncertainty analysis of ecological process parameters and CO_(2)flux components(Reco,NEE and gross ecosystem exchange(GEE))derived from 3 years’continuous eddy covariance meas-urements of CO_(2)fluxes at subtropical evergreen coniferous plantation,Qianyanzhou of ChinaFlux.Daily-differencing approach was used to analyze the random error of CO_(2)fluxes measurements and bootstrapping method was used to quantify the uncertainties of three CO_(2)flux components.In addition,we evaluated different models and optimization methods in influencing estimation of key parameters and CO_(2)flux components.The results show that:(1)Random flux error more closely follows a dou-ble-exponential(Laplace),rather than a normal(Gaussian)distribution.(2)Different optimization meth-ods result in different estimates of model parameters.Uncertainties of parameters estimated by the maximum likelihood estimation(MLE)are lower than those derived from ordinary least square method(OLS).(3)The differences between simulated Reco,NEE and GEE derived from MLE and those derived from OLS are 12.18%(176 g C·m-2·a-1),34.33%(79 g C·m-2·a-1)and 5.4%(92 g C·m-2·a-1).However,for a given parameter optimization method,a temperature-dependent model(T_model)and the models derived from a temperature and water-dependent model(TW_model)are 1.31%(17.8 g C·m-2·a-1),2.1%(5.7 g C·m-2·a-1),and 0.26%(4.3 g C·m-2·a-1),respectively,which suggested that the optimization methods are more important than the ecological models in influencing uncertainty in estimated carbon fluxes.(4)The relative uncertainty of CO_(2)flux derived from OLS is higher than that from MLE,and the uncertainty is related to timescale,that is,the larger the timescale,the smaller the uncertainty.The relative uncertainties of Reco,NEE and GEE are 4%-8%,7%-22%and 2%-4%respectively at annual timescale.
