The ecological city is a result of development of urban ecology,which is a living area of society s harmonious,high efficiency,ecological benign cycle.

Position floating——the best tactics in the realization of a virtuous circle among librarians;

At last, according to what one has gained from teaching practice, the author discussed how to improve the level of foreign teaching and bring about virtuous circle of teaching.

It is founded on people that this science development concept and has embodied with together rich unification, the unification that has embodied assurance economic law and natural law has embodied the unification of 4 virtuous circles, has embodied the unification of quantity and the quality of econom.

The fundamental guarantee of the benign circle ofcredit relationship:to establish and perfect the risk management system of enterprise s financial leasing;

Due to the change of medical model, disease spectrum and age structure of population, community health service and medical insurance should cooperate, and gradually form an economic benign circle in order to provide primary care timely and control health expenditure effectively.

This paper continues the research of method for discovering knowledge with "increase" or "decrease" properties and "circle" properties(benign circle or vicious circle) in data stream that its unit is relation.

China s sustainable agriculture should be not only based on the agriculture modernization but also realize benign circulation of the eco-economic system.

This paper analyzes on the interactive relation between the ecological consumption and the ecological technology, and advances the suggestion on establishing the benign circulation mechanism between the ecological consumption and the ecological technology.