Since the late 1990s, the housing affordability issue has aroused exceedingly heated discussion in Shanghai. The boom of the market, however, attracts frantic speculation that generates some serious problems in Shanghai, especially the severe inflation of house price. This paper investigates the dynamic factors that could drive up the house price in Shanghai emerging house market. Since delays, feedbacks and nonlinearities in house market are usually out of the reach of people's mental model, a system dynamics based model is developed to capture the underlying dynamic interactions among the different sectors involved in the real estate market, we study how they all together induce and exaggerate the affordability problem for local households. The policy tests demonstrate that the results of some already approved measures are counterintuitive or unsystematic, and show that only the systematic analysis and policy design can generate effective and radical solutions to the current problem.

All the countries in the world have done enormous work on lawmaking, technical problems of recycling engineering, managerial problems of recycling and the building of recycling plants, which has played an active role in regulating and promoting the recycling of waste electrical and electronic equipment. However, our country is still studying such system in the phase of a trial run, without considering recycling and processing as an entire system. Although the processing plants have been introduced, a recycling system is urgently needed to be set up. This thesis has put forward three applicable basic models in dealing with the recycling waste electrical and electronic equipment in the base of extended producer responsibility