The underground economy, which is an anti order phenomenon in the life of social economy, is indirectly estimated from whole social freight traffic that will be helpful to knowing the real scale of the national econom...The underground economy, which is an anti order phenomenon in the life of social economy, is indirectly estimated from whole social freight traffic that will be helpful to knowing the real scale of the national economy of China.展开更多
The increasing imbalance between road and maritime transport has led to saturation of the terrestrial infrastructures. For this reason, the development and analysis of an intermodal freight transport which is safe, re...The increasing imbalance between road and maritime transport has led to saturation of the terrestrial infrastructures. For this reason, the development and analysis of an intermodal freight transport which is safe, reliable and sustainable is the first step to a more balanced growth of other transport options. In this sense, SSS (Short Sea Shipping) rises like a real and efficient alternative to the land road-based transport as well as integrated to a multimodal system door to door for the freight distribution. This paper aims to evaluate and identify all those parameters required to determine the characteristics ofa SSS service under a theoretical approach. The increasing growth of the transport market demands to the maritime transport an adaptation effort to the redistribution space processes of production centers and consumption and, as a result of it, of the logistic flows and transport. For this reason, a specific methodology has been developed to model all those phases integrated in the logistic chain of SSS. The final purpose is to determine costs and time of each one of them, for its later implementation in a heuristic algorithm of routing analysis. The main driving factors that determine under which conditions the SSS represents an effective and a feasible solution to road freight are also identified. Information regarding European Union programs to promote the SSS is also presented for a better understanding of the ways of funding sustainable freight transport projects. This investigation states an initial basis for evaluating the competitiveness of SSS concepts, and shows where market and environmental circumstances could be handled in order to enhance the competitiveness of SSS.展开更多
In quantum mechanics theory one of the basic operator orderings is Q-P and P-Q ordering,where Q and P are the coordinate operator and the momentum operator,respectively.We derive some new fundamental operator identiti...In quantum mechanics theory one of the basic operator orderings is Q-P and P-Q ordering,where Q and P are the coordinate operator and the momentum operator,respectively.We derive some new fundamental operator identities about their mutual reordering.The technique of integration within Q-P ordering and P-Q ordering is introduced.The Q-P ordered and P-Q ordered formulas of the Wigner operator are also deduced which makes arranging the operators in either Q-P or P-Q ordering much more convenient.展开更多
文摘The underground economy, which is an anti order phenomenon in the life of social economy, is indirectly estimated from whole social freight traffic that will be helpful to knowing the real scale of the national economy of China.
文摘The increasing imbalance between road and maritime transport has led to saturation of the terrestrial infrastructures. For this reason, the development and analysis of an intermodal freight transport which is safe, reliable and sustainable is the first step to a more balanced growth of other transport options. In this sense, SSS (Short Sea Shipping) rises like a real and efficient alternative to the land road-based transport as well as integrated to a multimodal system door to door for the freight distribution. This paper aims to evaluate and identify all those parameters required to determine the characteristics ofa SSS service under a theoretical approach. The increasing growth of the transport market demands to the maritime transport an adaptation effort to the redistribution space processes of production centers and consumption and, as a result of it, of the logistic flows and transport. For this reason, a specific methodology has been developed to model all those phases integrated in the logistic chain of SSS. The final purpose is to determine costs and time of each one of them, for its later implementation in a heuristic algorithm of routing analysis. The main driving factors that determine under which conditions the SSS represents an effective and a feasible solution to road freight are also identified. Information regarding European Union programs to promote the SSS is also presented for a better understanding of the ways of funding sustainable freight transport projects. This investigation states an initial basis for evaluating the competitiveness of SSS concepts, and shows where market and environmental circumstances could be handled in order to enhance the competitiveness of SSS.
基金supported by the National Natural Science Foundation of China (Grant No.11175113)
文摘In quantum mechanics theory one of the basic operator orderings is Q-P and P-Q ordering,where Q and P are the coordinate operator and the momentum operator,respectively.We derive some new fundamental operator identities about their mutual reordering.The technique of integration within Q-P ordering and P-Q ordering is introduced.The Q-P ordered and P-Q ordered formulas of the Wigner operator are also deduced which makes arranging the operators in either Q-P or P-Q ordering much more convenient.