In this paper, a two\|sector growth model is given. The labor force transfer process from agricultural sector to industrial sector is exogenous determined. By introducing the labor force transferring function, a two\|...In this paper, a two\|sector growth model is given. The labor force transfer process from agricultural sector to industrial sector is exogenous determined. By introducing the labor force transferring function, a two\|dimension nonautonomous differential equation is obtained. The results of the model manifest that the labor force transfer delays industrial sector growth and accelerates the agricultural sector growth. It is proved that the solution of the model is asymptotic stable. By the numerical analysis, the economic growth and labor force transfer is presented under the specific parameters.展开更多
Terminal airspace(TMA)is the airspace centering several military and civil aviation airports with complex route structure,limited airspace resources,traffic flow,difficult management and considerable airspace complexi...Terminal airspace(TMA)is the airspace centering several military and civil aviation airports with complex route structure,limited airspace resources,traffic flow,difficult management and considerable airspace complexity.A scientific and rational sectorization of TMA can optimize airspace resources,and sufficiently utilize the control of human resources to ensure the safety of TMA.The functional sectorization model was established based on the route structure of arriving and departing aircraft as well as controlling requirements.Based on principles of sectorization and topological relations within a network,the arrival and departure sectorization model was established,using tree based ant colony algorithm(ACO)searching.Shanghai TMA was taken as an example to be sectorizaed,and the result showed that this model was superior to traditional ones when arrival and departure routes were separated at dense airport terminal airspace.展开更多
Since reform and opening-up in 1978, changes in China's industrial structure have generally followed the pattern of "Kuznets facts" but still exhibits some unique characteristics, which led us to raise t...Since reform and opening-up in 1978, changes in China's industrial structure have generally followed the pattern of "Kuznets facts" but still exhibits some unique characteristics, which led us to raise the following three questions regarding China's structural transformation:(1) Why did the share of China's agricultural and manufacturing employment reduce/increase intermittently rather than continuously?(2) Why did the share of China's agricultural employment increase during certain periods? When the share of manufacturing employment reduced, why did the workforce reversely flow into agriculture rather than move to the service sector?(3) Why did growth in the share of China's service sector employment decelerate before reaching its peak? Why did the share of employment in the industrial sector suddenly increase after an abrupt decline? This paper creates a multisector economic growth model that contains non-homothetic preferences and differentiated productivity, and incorporates the "two drivers" therein for a demand-side estimation and analysis. The result shows that China's economic growth model driven by net export and investment is a critical factor for explaining the three questions regarding its structural transformation. This paper believes that only by implementing supply-side structural reforms, reducing the dependence on net export and investment, and achieving sustainable endogenous economic growth will China be able to expedite its industrial restructuring.展开更多
Climate change is expected to have substantial effects on agricultural productivity worldwide. However, these impacts will differ across commodities, locations and time periods. As a result, landowners will see change...Climate change is expected to have substantial effects on agricultural productivity worldwide. However, these impacts will differ across commodities, locations and time periods. As a result, landowners will see changes in relative returns that are likely to induce modifications in production practices and land allocation. In addition, regional variations in impacts can alter relative competitiveness across countries and lead to adjustments in international trade patterns. Thus in climate change impact studies it is likely useful to account for worldwide productivity effects. In this study, we investigate the implications of considering rest of world climate impacts on projections of the US agricultural exports. We chose to focus on the US because it is one of the largest agricultural exporters. To conduct our analyses, we consider four alternative climate scenarios, both with and without rest of world climate change impacts. Our results show that considering/ignoring rest of world climate impacts causes significant changes in the US production and exports projections. Thus we feel climate change impact studies should account not only for climate impacts in the country of focus but also on productivity in the rest of the world in order to capture effects on commodity markets and trade potential.展开更多
文摘In this paper, a two\|sector growth model is given. The labor force transfer process from agricultural sector to industrial sector is exogenous determined. By introducing the labor force transferring function, a two\|dimension nonautonomous differential equation is obtained. The results of the model manifest that the labor force transfer delays industrial sector growth and accelerates the agricultural sector growth. It is proved that the solution of the model is asymptotic stable. By the numerical analysis, the economic growth and labor force transfer is presented under the specific parameters.
基金supported by the National Natural Science Foundation of China(Nos.U1233101,71271113)the Fundamental Research Funds for the Central Universities(No.NS2016062)
文摘Terminal airspace(TMA)is the airspace centering several military and civil aviation airports with complex route structure,limited airspace resources,traffic flow,difficult management and considerable airspace complexity.A scientific and rational sectorization of TMA can optimize airspace resources,and sufficiently utilize the control of human resources to ensure the safety of TMA.The functional sectorization model was established based on the route structure of arriving and departing aircraft as well as controlling requirements.Based on principles of sectorization and topological relations within a network,the arrival and departure sectorization model was established,using tree based ant colony algorithm(ACO)searching.Shanghai TMA was taken as an example to be sectorizaed,and the result showed that this model was superior to traditional ones when arrival and departure routes were separated at dense airport terminal airspace.
文摘Since reform and opening-up in 1978, changes in China's industrial structure have generally followed the pattern of "Kuznets facts" but still exhibits some unique characteristics, which led us to raise the following three questions regarding China's structural transformation:(1) Why did the share of China's agricultural and manufacturing employment reduce/increase intermittently rather than continuously?(2) Why did the share of China's agricultural employment increase during certain periods? When the share of manufacturing employment reduced, why did the workforce reversely flow into agriculture rather than move to the service sector?(3) Why did growth in the share of China's service sector employment decelerate before reaching its peak? Why did the share of employment in the industrial sector suddenly increase after an abrupt decline? This paper creates a multisector economic growth model that contains non-homothetic preferences and differentiated productivity, and incorporates the "two drivers" therein for a demand-side estimation and analysis. The result shows that China's economic growth model driven by net export and investment is a critical factor for explaining the three questions regarding its structural transformation. This paper believes that only by implementing supply-side structural reforms, reducing the dependence on net export and investment, and achieving sustainable endogenous economic growth will China be able to expedite its industrial restructuring.
文摘Climate change is expected to have substantial effects on agricultural productivity worldwide. However, these impacts will differ across commodities, locations and time periods. As a result, landowners will see changes in relative returns that are likely to induce modifications in production practices and land allocation. In addition, regional variations in impacts can alter relative competitiveness across countries and lead to adjustments in international trade patterns. Thus in climate change impact studies it is likely useful to account for worldwide productivity effects. In this study, we investigate the implications of considering rest of world climate impacts on projections of the US agricultural exports. We chose to focus on the US because it is one of the largest agricultural exporters. To conduct our analyses, we consider four alternative climate scenarios, both with and without rest of world climate change impacts. Our results show that considering/ignoring rest of world climate impacts causes significant changes in the US production and exports projections. Thus we feel climate change impact studies should account not only for climate impacts in the country of focus but also on productivity in the rest of the world in order to capture effects on commodity markets and trade potential.