It is very useful to utilize a snow air-conditioning system with stored snow not only for saving the fossil energy but also for keeping the environment clean. In a snow air-conditioning system, I can divide it into an air circulation method to make air a medium as a type to get coldness from snow and a cold water circulation type through the medium of the water. The cold water circulation type needs the removal of filth included in melting snow water, but, in comparison with the air circulation type, there is the merit that is easy to acquire coldness from snow. However, by the cold water circulation type, water is taken in like a sponge at the lower part of the snowy layer, and a delay grows big in time to get cold water, and therefore there is the report that control characteristics can lack in. Therefore, by this report, I paid attention to heat exchange in the lower part of the snowy layer. The lower part of the snowy layer forms a way of the water so that snowmelt flows. With this, it becomes difficult to get stable cold water. Therefore, we installed a small weir to let the snowy lower part inundation forcibly. By this, we prevented the formation of the way of the water and grasped a heat exchange characteristic in the lower part of the snowy layer. As a result, we developed the new snow air-conditioning system which could get cold water in stability and simpleness from snow. We demonstrated this result and applied it to the air conditioner of the real institution.

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Freezing experiment of sodium chloride (NaCl) solution on an asphalt pavement was carried out and the mass ice content, i, and the concentration NaCl, C s, were measured at different elapsed time of the experiment.A forecast model of snow/ice condition on a road developed by authors could reproduce the increase in i and C s due to freezing. Our model, furthermore, could reproduce the decrease in the resistance (BPN) of the asphalt pavement covered with NaCl solution due to freezing using the BPN- i relation obtained from our another experiment.

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In this research, the role of local railways in snowfall and depopulated areas is explored, and the fundamental information about these railways is offered. The results are as follows. 1) As a result of Trend Search Analysis, Everydayness, Sightseeing, Local Support, Management and Profitability and Scenery are the five which existed in the target local railway as an image. 2) There is a tendency of demand which respects Local Support in snowfall and depopulated areas, and Scenery and Sightseeing in depopulated areas, and Management and Profitability in snowfall areas. 3) The problems about local railways in snowfall and depopulated areas were shown by the case studies.

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