China's rapid urbanization in the past 30 years can be abstracted as a spatial-temporal product of the socio-economic mechanism relying on productive factors, which represents the sustained dynamics from labor dem...China's rapid urbanization in the past 30 years can be abstracted as a spatial-temporal product of the socio-economic mechanism relying on productive factors, which represents the sustained dynamics from labor demographic bonus to land capital discount. In the context of the current increasing global complexity, this paper points out that this kind of productive factor-based spatial logic not only has structural deficiencies, but also potentially brings about the environmental, economic, social, and political risks in multiple dimensions as follows: first, the crises in regional resources and environment due to the market distortion of productive factors; second, the disappearance of industrial growth impetus due to the investment preference to land urbanization; third, the social polarization caused by the incomplete urbanization of immigrates; fourth, the overdraft of government credit as a result of the unbalanced urbanization of population, industry, and land. Under such a circumstance, the paper proposes a transition of China's existing urbanization policies, so as to achieve the objective of sustainable urbanization in the future.展开更多
Steering light into logic patterns with two-dimensional cascaded multimode waveguide is demonstrated. By employing the imaging properties of 2D multimode interference （MMI） and partial phase modulation method, the d...Steering light into logic patterns with two-dimensional cascaded multimode waveguide is demonstrated. By employing the imaging properties of 2D multimode interference （MMI） and partial phase modulation method, the design ideas and the implementing methods of the 2^（2×2） bits type spatial logic steering are discussed; therefore the structure of logical pattern is proposed. Numerical simulation is carried out to verify the design in detail by using the beam propagation method. It is expected to realize logic coders by using the integrated optical methods and exploit their potential applications in the field of optical logic.展开更多
基金Supported by National Natural Sciences Fund(No.50808112)2012 Elementary Science Research Fund for Central Universities to Dalian University of Technology(No.DUT12RW430.)
文摘China's rapid urbanization in the past 30 years can be abstracted as a spatial-temporal product of the socio-economic mechanism relying on productive factors, which represents the sustained dynamics from labor demographic bonus to land capital discount. In the context of the current increasing global complexity, this paper points out that this kind of productive factor-based spatial logic not only has structural deficiencies, but also potentially brings about the environmental, economic, social, and political risks in multiple dimensions as follows: first, the crises in regional resources and environment due to the market distortion of productive factors; second, the disappearance of industrial growth impetus due to the investment preference to land urbanization; third, the social polarization caused by the incomplete urbanization of immigrates; fourth, the overdraft of government credit as a result of the unbalanced urbanization of population, industry, and land. Under such a circumstance, the paper proposes a transition of China's existing urbanization policies, so as to achieve the objective of sustainable urbanization in the future.
基金Project supported by the National Natural Science Foundation of China （Grant No 60477018） and the Major Program of the National Natural Science Foundation of China （Grant No 60436020）.
文摘Steering light into logic patterns with two-dimensional cascaded multimode waveguide is demonstrated. By employing the imaging properties of 2D multimode interference （MMI） and partial phase modulation method, the design ideas and the implementing methods of the 2^（2×2） bits type spatial logic steering are discussed; therefore the structure of logical pattern is proposed. Numerical simulation is carried out to verify the design in detail by using the beam propagation method. It is expected to realize logic coders by using the integrated optical methods and exploit their potential applications in the field of optical logic.
