Due to the rapid growth of the IT industry as well as the high failure rate of software development projects, it is highly desirable to develop a qualitative approach for dealing with uncertainties in the software development process. In order to manage risk and uncertainty, a software project uncertainty management approach based on a generalized stochastic Petri net is proposed. It consists of two main components: model building based on a Petri net and a Markov process algorithm. The technique is presented with an example. Finally, the proposed model is demonstrated with a real-world case.

Xian Sanxuejie district is a typical historic district of the city. Presently this type of traditional districts is surrounded by many modern buildings due to the rapid urban expansion. The historic districts are facing problems of poor courtyard micro-climate conditions and low living level, which has become the bottleneck of historic districts sustainable development. This paper studies thermal environment, luminous environment, solar environment and wind environment from a new perspective using Ecotect building environment analyzing software. The author explores micro-climate improving method suitable for traditional courtyard in order to promote micro-climate quality of historic district and to improve the comfort of local residences. The purpose is to achieve sustainable development of historic districts.