Developmental Study of Instrumentation for Properties of Snow

点击翻译按钮获取中文摘要

For prevention and mitigation against the snow disaster due to heavy snowfall and deep snow cover,it is of great importance to get some information about snow quantities and snow qualities as quick as possible.Several types of instruments for detecting falling snow have been made, however, the expense and cost of them are not yet efficient for general treatment and observations. The objectives of this research are of manufacturing a cheaper and compacted high expense apparatus for snow flakes and to establish a systematic method for analyzing the nature of snow through field testings.The present investigations reported herein are the following items. 1) Observations of snow flakes in both coastal and mountain side regions were performed by the existing facilities to compare regional characteristics. Besides of this work, properties of depositted snow were studied for comparing the regionalities. 2) Four different instruments for detecting snow flakes were newly manufactured as followings. (1)Infrared slit falling snow sensor (2)Multiple infrared slit falling snow sensor (3)Infrared silhoutte falling snow sensor (4)Infrared transmission snow sensor by optical sensing method Performance tests of these detecting systems recognized that new systems worked well and were more useful to detect the intensity of snow falling compare with the existing instrument. 3) An another analytical method was developed by using a video camera, an image processor and a high speed micro computer. This system is enable to distinguish the different snow flake sizes , shapes and a density of snow particles in air. 4) An effective index for snow damage forecasting were proposed by data analyses of daily snow depth depending on the regionalities.The details of this research were published and posted to reference organizations. The results obtained in this research would give the scientific information to build up the forecasting and mitigation systems of snow damages.