The recently developed Spring Back Reflector has low stiffness in the deployed configuration. A general method of stiffening this type of reflector without changing its folding properties is presented. The stiffening is achieved by adding a conical skirt around the edge of the dish; this skirt snaps elastically when the dish is folded. The paper concludes that it is possible to design spring ba...

Beijing’s mountainous areas have an important ecological significance because they are ecological conservation and water source protection areas of Beijing. The impact of precipitation on the vegetation coverage of Beijing’s mountainous areas is qualitatively analyzed using multi-temporal Landsat images obtained during the last 20 years. Firstly, the influence of external factors, such as pheno...

In this paper, we analyze the effect of light conditions on road accidents and estimate long-run consequences different time regimes for safety. Identification is based variation in induced by differences sunrise sunset times across space time. We that darkness causes annual costs more than £500 million Great Britain. By setting daylight saving year-round, 8% these could be saved. Thus, focusin...