Since the eruption of the recent global financial crisis, major countries have been pushing forward structural reforms with science and technology （S＆T） innovation at the heart. Since taking office, US President Do...Since the eruption of the recent global financial crisis, major countries have been pushing forward structural reforms with science and technology （S＆T） innovation at the heart. Since taking office, US President Donald Trump has adopted an ＂America First＂ strategy but has yet to specify a clear S＆T innovation policy. However, Trump＇s current policies have already affected S＆T innovation and his planned budget cuts will impact US growth potentials. Compared with the US, China is steadily implementing its innovation-driven development strategy with significant improvement in S＆ T innovation that increasingly supports economic growth. To spur future economic growth, China should steadfastly follow its S＆T innovation strategy, promote the utilization of S＆T innovation results, boost its economic growth potentials and make the most of global innovation resources.展开更多
Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vini...Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vinifera and apple were discussed.The coping technology for climate changing and measurements for serving the agricultural were provided.展开更多
The transplanting period, density, the number of left leaves and fertilizer amounts of HQ No.1 were explored in Hengyang. The results showed that with transplanting periods of March 5-March 15, and planting space of 1...The transplanting period, density, the number of left leaves and fertilizer amounts of HQ No.1 were explored in Hengyang. The results showed that with transplanting periods of March 5-March 15, and planting space of 120 cmx（50-60） cm, agronomic and economic characters of tobaccos showed insignificant differences. Specifically, plant height was growing upon the number of left leaf and fertilizer amount; tobacco yield and output value kept increasing upon fertilizer, and both reached maximums with pure N at 195 kg/hm^2, showing significant differences with the treatment of pure N at 135 kg/hm^2; the number of left leaf had the least effects on agronomic and economic characters of tobaccos. The research indicated that highly-qualified HQ No.1 can be produced, given that tobaccos are transplanted during March 10-March 15, planting density of 15 000-16 500 seedlings/hm^2, the number of left leaves of 22-24 leaves per seedling, and pure N of 150-165 kg/hm^2 in Hengyang.展开更多
In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity ...In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity of land use needs to be evaluated. The current method of comprehensive evaluation and grading by one index system has the limitations due to the existence of differences between regions and industries. This paper evaluates industrial land use intensity by Total Factor Productivity (TFP) analysis, which not only measures the intensity but also illustrates the ef-ficiency of input factors. This method is applied to the Beijing Economic-technological Development Area (BDA). A comparison analysis on factor use efficiency and input structure of capital and labor between industries is also carried out in the absence of a labor-income ratio.展开更多
Three gas separation technologies,chemical absorption,membrane separation and pressure swing adsorption,are usually applied for CO2 capture from flue gas in coal-fired power plants.In this work,the costs of the three ...Three gas separation technologies,chemical absorption,membrane separation and pressure swing adsorption,are usually applied for CO2 capture from flue gas in coal-fired power plants.In this work,the costs of the three technologies are analyzed and compared.The cost for chemical absorption is mainly from $30 to $60 per ton(based on CO2 avoided),while the minimum value is $10 per ton(based on CO2 avoided).As for membrane separation and pressure swing adsorption,the costs are $50 to $78 and $40 to $63 per ton(based on CO2 avoided),respectively.Measures are proposed to reduce the cost of the three technologies.For CO2 capture and storage process,the CO2 recovery and purity should be greater than 90%.Based on the cost,recovery,and purity,it seems that chemical absorption is currently the most cost-effective technology for CO2 capture from flue gas from power plants.However,membrane gas separation is the most promising alternative approach in the future,provided that membrane performance is further improved.展开更多
Regarding excavation-damaged zone （EDZ） around underground opening as non-homogeneous rockmass with spatial deterioration effect on stuffiness and strength, a parametric model of EDZ using radius-displacement-depend...Regarding excavation-damaged zone （EDZ） around underground opening as non-homogeneous rockmass with spatial deterioration effect on stuffiness and strength, a parametric model of EDZ using radius-displacement-dependent deformation modulus （RDDM） was proposed. Considering the nonlinearity characteristic of deformation and locality otherness of surrounding rock, deterioration parameter field of deformation modulus of rockmass around opening was quantitatively calculated through a given function. Applicability for multi-cavern condition and parameter sensibility of the model was analyzed by numerical experiments using synthetic data. Furthermore, the model was applied to identify EDZ of underground caverns of Pubugou hydropower station by calculating deterioration parameter field. Based on the parametric analysis of spatial effect and geological investigation, it is recognized that large radial deformation of deep fractured rock at the spandrel position and insufficient supporting bolts mainly result in great deformation pressure to act on the shotcrete and cause partial crack and spalling. It is shown that deterioration parameter field along the longitudinal axis of main powerhouse is evidently non-homogeneous in space and distributes exponentially along the radius from the opening. The model provides a simple and convenient way to identify the EDZ in the working state for rapid construction feedback analysis and support optimization of underground cavem from quantitative point of view and also aids in interpreting monitoring displacements and estimating support requirements.展开更多
The study measures productive efficiency of tomato growers in village Akbarpura of Disctrict Nowshera in Khyber Pakhtunkhwa （KPK） province of Northern Pakistan. The study uses household level data collected in summe...The study measures productive efficiency of tomato growers in village Akbarpura of Disctrict Nowshera in Khyber Pakhtunkhwa （KPK） province of Northern Pakistan. The study uses household level data collected in summer 2010 from sample farmers selected by multi-staged sampling. The study uses a theoretical framework to measure productive efficiency and estimates the Cobb-Douglas frontier production and cost models. The study found that technical efficiency indices varied significantly, with technical efficiency index averaging at 65%. The indices of allocative efficiency also varied widely, with an average of 56%. There was a wide gap between the highest and lowest economic efficiency indices, with a mean economic efficiency of 35%. The study concluded that farmer education, extension visits, age and access to credit contributed significantly and positively to productive efficiencies. A policy implication of this study is that there is enough potential for farmers to increase tomato production and net profits. The study recommends that the government should further invest in public education and strengthen extension services farmer education and because extension visits constituted important determinants of productive efficiencies.展开更多
In this study,the authors introduce a new bogus data assimilation method based on the dimension-reduced projection 4-DVar,which can resolve the cost function directly in low-dimensional space.The authors also try a ne...In this study,the authors introduce a new bogus data assimilation method based on the dimension-reduced projection 4-DVar,which can resolve the cost function directly in low-dimensional space.The authors also try a new method to improve the quality of samples,which are the base of dimension-reduced space projection bogus data assimilation (DRP-BDA).By running a number of numerical weather models with different model parameterization combinations on the typhoon Sinlaku,the authors obtained two groups of samples with different spreads and similarities.After DRP-BDA,the results show that,compared with the control runs,the simulated typhoon center pressure can be deepened by more than 20 hPa to 30 hPa and that the intensity can last as long as 60 hours.The mean track error is improved after DRP-BDA,and the structure of the typhoon is also improved.The wind near the typhoon center is enhanced dramatically,while the warm core is moderate.展开更多
The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis ...The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis （SBM-DEA） has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency （OE） of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency （SE） was higher than the pure technological efficiency （PTE）; PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped＇ trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle展开更多
The land use patterns in Guyuan City,Ningxia Hui Autonomous Region of China,have changed greatly over the years,due to population growth and farming and stock raising development.This study,using 50-year statis-tical ...The land use patterns in Guyuan City,Ningxia Hui Autonomous Region of China,have changed greatly over the years,due to population growth and farming and stock raising development.This study,using 50-year statis-tical data of cultivated land and 14-year spatial data of land use pattern,analyzed the developmental stages,the char-acter,and the spatial variance of farmland in the city,and discussed the driving forces of cultivated land changes based on empirical and conceptual statistical models.First,the change of cultivated land area went through different stages of rapid increase,fluctuating change,decrease and rapid decrease from 1949 to 2004,additionally,social and economic policies in different stages had an important impact on farmland variance.Second,from 1986 to 2000,the quantity of cultivated land increased,but its quality decreased.Third,social and economic factors are determinant factors in culti-vated land transition.Five constructed paths explain cultivated land transition.Factors that have direct or indirect ef-fects on farmland include the economy(Xeco),the population(Xpop),agricultural output(Xagr),and scientific input(Xsci).The sequence of impact was Xeco>Xpop>Xsci>Xagr.Among all these impacts,Xeco was the major positive one,and Xpop was the major negative one.It is urgent to take measures or adopt a policy to stop the vicious cycle in eco-environment and agriculture production.Otherwise,negative patterns of farmland use will increase,and high-quality cultivated land will continue to decline.展开更多
文摘Since the eruption of the recent global financial crisis, major countries have been pushing forward structural reforms with science and technology （S＆T） innovation at the heart. Since taking office, US President Donald Trump has adopted an ＂America First＂ strategy but has yet to specify a clear S＆T innovation policy. However, Trump＇s current policies have already affected S＆T innovation and his planned budget cuts will impact US growth potentials. Compared with the US, China is steadily implementing its innovation-driven development strategy with significant improvement in S＆ T innovation that increasingly supports economic growth. To spur future economic growth, China should steadfastly follow its S＆T innovation strategy, promote the utilization of S＆T innovation results, boost its economic growth potentials and make the most of global innovation resources.
基金Supported by Special Fund of Public Industry from Ministry of Science and Technology (GYHY200806021)National Natural Science Foundation Emphases Item of China (40830957)+2 种基金Project of Researches on Drought Meteorological Science (IAM200811)Special Fund for Climatic Change in China Meteorological Bureau (CCSS-09-14)Technology-aid Project in Gansu (090NKCA118)~~
文摘Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vinifera and apple were discussed.The coping technology for climate changing and measurements for serving the agricultural were provided.
文摘The transplanting period, density, the number of left leaves and fertilizer amounts of HQ No.1 were explored in Hengyang. The results showed that with transplanting periods of March 5-March 15, and planting space of 120 cmx（50-60） cm, agronomic and economic characters of tobaccos showed insignificant differences. Specifically, plant height was growing upon the number of left leaf and fertilizer amount; tobacco yield and output value kept increasing upon fertilizer, and both reached maximums with pure N at 195 kg/hm^2, showing significant differences with the treatment of pure N at 135 kg/hm^2; the number of left leaf had the least effects on agronomic and economic characters of tobaccos. The research indicated that highly-qualified HQ No.1 can be produced, given that tobaccos are transplanted during March 10-March 15, planting density of 15 000-16 500 seedlings/hm^2, the number of left leaves of 22-24 leaves per seedling, and pure N of 150-165 kg/hm^2 in Hengyang.
基金Under the auspices of Fundamental Research Funds for the Central Universities (No. 2009SD-5)
文摘In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity of land use needs to be evaluated. The current method of comprehensive evaluation and grading by one index system has the limitations due to the existence of differences between regions and industries. This paper evaluates industrial land use intensity by Total Factor Productivity (TFP) analysis, which not only measures the intensity but also illustrates the ef-ficiency of input factors. This method is applied to the Beijing Economic-technological Development Area (BDA). A comparison analysis on factor use efficiency and input structure of capital and labor between industries is also carried out in the absence of a labor-income ratio.
基金Supported by the National High Technology Research and Development Program of China (2007AA03Z229)the Fundamental Research Funds for the Central Universities (2009ZM0185)
文摘Three gas separation technologies,chemical absorption,membrane separation and pressure swing adsorption,are usually applied for CO2 capture from flue gas in coal-fired power plants.In this work,the costs of the three technologies are analyzed and compared.The cost for chemical absorption is mainly from $30 to $60 per ton(based on CO2 avoided),while the minimum value is $10 per ton(based on CO2 avoided).As for membrane separation and pressure swing adsorption,the costs are $50 to $78 and $40 to $63 per ton(based on CO2 avoided),respectively.Measures are proposed to reduce the cost of the three technologies.For CO2 capture and storage process,the CO2 recovery and purity should be greater than 90%.Based on the cost,recovery,and purity,it seems that chemical absorption is currently the most cost-effective technology for CO2 capture from flue gas from power plants.However,membrane gas separation is the most promising alternative approach in the future,provided that membrane performance is further improved.
基金Project(2010CB732005) supported by the National Basic Research Program of ChinaProjects(51279136, 51209164) supported by the National Natural Science Foundation of China
文摘Regarding excavation-damaged zone （EDZ） around underground opening as non-homogeneous rockmass with spatial deterioration effect on stuffiness and strength, a parametric model of EDZ using radius-displacement-dependent deformation modulus （RDDM） was proposed. Considering the nonlinearity characteristic of deformation and locality otherness of surrounding rock, deterioration parameter field of deformation modulus of rockmass around opening was quantitatively calculated through a given function. Applicability for multi-cavern condition and parameter sensibility of the model was analyzed by numerical experiments using synthetic data. Furthermore, the model was applied to identify EDZ of underground caverns of Pubugou hydropower station by calculating deterioration parameter field. Based on the parametric analysis of spatial effect and geological investigation, it is recognized that large radial deformation of deep fractured rock at the spandrel position and insufficient supporting bolts mainly result in great deformation pressure to act on the shotcrete and cause partial crack and spalling. It is shown that deterioration parameter field along the longitudinal axis of main powerhouse is evidently non-homogeneous in space and distributes exponentially along the radius from the opening. The model provides a simple and convenient way to identify the EDZ in the working state for rapid construction feedback analysis and support optimization of underground cavem from quantitative point of view and also aids in interpreting monitoring displacements and estimating support requirements.
文摘The study measures productive efficiency of tomato growers in village Akbarpura of Disctrict Nowshera in Khyber Pakhtunkhwa （KPK） province of Northern Pakistan. The study uses household level data collected in summer 2010 from sample farmers selected by multi-staged sampling. The study uses a theoretical framework to measure productive efficiency and estimates the Cobb-Douglas frontier production and cost models. The study found that technical efficiency indices varied significantly, with technical efficiency index averaging at 65%. The indices of allocative efficiency also varied widely, with an average of 56%. There was a wide gap between the highest and lowest economic efficiency indices, with a mean economic efficiency of 35%. The study concluded that farmer education, extension visits, age and access to credit contributed significantly and positively to productive efficiencies. A policy implication of this study is that there is enough potential for farmers to increase tomato production and net profits. The study recommends that the government should further invest in public education and strengthen extension services farmer education and because extension visits constituted important determinants of productive efficiencies.
基金the Ministry of Finance of China and the China Meteorological Administration for the Special Project of Meteorological Sector (Grant No. GYHY(QX)200906009)the National Natural Science Foundation of China for the innovation group project (Grant No.40821092)
文摘In this study,the authors introduce a new bogus data assimilation method based on the dimension-reduced projection 4-DVar,which can resolve the cost function directly in low-dimensional space.The authors also try a new method to improve the quality of samples,which are the base of dimension-reduced space projection bogus data assimilation (DRP-BDA).By running a number of numerical weather models with different model parameterization combinations on the typhoon Sinlaku,the authors obtained two groups of samples with different spreads and similarities.After DRP-BDA,the results show that,compared with the control runs,the simulated typhoon center pressure can be deepened by more than 20 hPa to 30 hPa and that the intensity can last as long as 60 hours.The mean track error is improved after DRP-BDA,and the structure of the typhoon is also improved.The wind near the typhoon center is enhanced dramatically,while the warm core is moderate.
基金Key Research Program of Chinese Academy of Sciences(No.KZZD-EW-06-03-03)
文摘The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis （SBM-DEA） has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency （OE） of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency （SE） was higher than the pure technological efficiency （PTE）; PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped＇ trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle
基金Under the auspices of Major State Basic Research Development Program of China (No. 2002CB111506)National Natural Science Foundation of China (No. 30670374)Sixth Framework Programme of European Union (Priority 1.1.6.3) (No. 003874-2)
文摘The land use patterns in Guyuan City,Ningxia Hui Autonomous Region of China,have changed greatly over the years,due to population growth and farming and stock raising development.This study,using 50-year statis-tical data of cultivated land and 14-year spatial data of land use pattern,analyzed the developmental stages,the char-acter,and the spatial variance of farmland in the city,and discussed the driving forces of cultivated land changes based on empirical and conceptual statistical models.First,the change of cultivated land area went through different stages of rapid increase,fluctuating change,decrease and rapid decrease from 1949 to 2004,additionally,social and economic policies in different stages had an important impact on farmland variance.Second,from 1986 to 2000,the quantity of cultivated land increased,but its quality decreased.Third,social and economic factors are determinant factors in culti-vated land transition.Five constructed paths explain cultivated land transition.Factors that have direct or indirect ef-fects on farmland include the economy(Xeco),the population(Xpop),agricultural output(Xagr),and scientific input(Xsci).The sequence of impact was Xeco>Xpop>Xsci>Xagr.Among all these impacts,Xeco was the major positive one,and Xpop was the major negative one.It is urgent to take measures or adopt a policy to stop the vicious cycle in eco-environment and agriculture production.Otherwise,negative patterns of farmland use will increase,and high-quality cultivated land will continue to decline.
