Research Of The Defense Safety Design In View Of Seasonal Variation Of Urban Public Space

city crime keeps high level,as well as the people's living quality improvement of the rapid development of urban economy.The urban public space is not only the space of people's activities and communication,but also the site of high incidence crime.And,there is a lot of factors to affect the defense safety of urban public space,in which the defense safety design in the perspective of seasonal variation is often neglected.The seasonal climate variation is a common natural phenomenon,which has special influences on the defense safety of urban public space.The state of urban public space shows the different appearances with seasonal variation,leading to defense safety of the space would also be affected.So we should carry on reasonable and effective defense safety design to focus on this special perspective.The paper analyze gradually from three aspects,starting from the physical environment affected by seasonal variation,then affecting the relationship between human and material elements,the last people's psychological feeling in space environment.It concludes the restrict factors of defense safety of urban public space that affected by seasonal variation,namely space environment elements(landscape system,road traffic and public facilities),space service condition(activity types,the number of people and the time of activities),and the space atmosphere(safety,comfort and attraction)three aspects.At the same time taking the warm and cold phases caused by seasonal variation as the basis,combining with the representative urban public space such as parks,squares and streets in Changchun for research.Finally the paper sums up the effects on the defense safety in each state,then puts forward corresponding design strategy focusing on those affects,for example,perfect the public facilities to increase activity support;enrich use function to improve the quality of space;Optimize the landscape system to improve environmental image and attention to detail design to enhance natural monitoring and so on.Through the research and analysis of this paper,we can improve the restrict factors in public space,increasing the difficulty of implementing crime,achieving the purpose of reducing or preventing crime,and providing auxiliary prophylaxis means of social safety problems under the conditions of season variation.