For systematic sliding of roof snow, appropriate evaluation of the frictional properties between roof snow and roofing materials is needed. Snow generally slides off a roof several days after accumulating on the roof due to changes in snow condition (newsnow→compacted snow→granular snow) caused by the transfer of heat from attic space. In this study, we experimentally investigated the temporal changes of roof snow and the accompanying changes in frictional properties between the snow and roofing material. The results showed that the size of snow particles gradually increases after snow has accumulated on the roof, and frictional resistance between the snow and coated steel sheets greatly decreases. Within 24-48 hours after accumulation of snow on the roof, the frictional resistance of the snow decreases to about one-third of that of newsnow. Thereafter, there is almost no change in frictional resistance. The results of this study show that consideration of the temporal decrease in frictional resistance between roof snow and roofing materials is important for planning systematic sliding of roof snow.

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A field test of Borehole Heat Exchanger System (BHES) has been carried out at a car park on Fukui University campus. The purpose of the present study is to reveal the structure, working principle and performance of the BHES. The BHES basically consists of a borehole and an asphalt surfaced pavement covering a concrete panel in which a heat exchanger loop has been incorporated. The borehole is 70m in length and comprises an inner and an outer pipe. A heat carrier liquid circulates between the pavement and the borehole. The performance of the BHES is experimentally evaluated from the pavement and liquid temperatures along the BHES for a few years.
It is shown that the BHES can prevent the pavement temperature from rising more then 20°C in summer and has the thermal energy to melt a continuous snow fall of 2-3cm/hour under typical weather conditions in Fukui.

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The purpose of this study was to obtain basic data for disaster prevention. We investigated cases of snow-related disaster that occurred in Hokkaido. The following results were obtained.
1) A proportional relationship was found between the number of snow-related disas-ter reported in newspapers and the number of such accidents reported to police ; the former was about one-third of the latter. Thus, this relationship can serve as an index of snow-related disaster in Hokkaido.
2) Examination of police records showed that most of the snow-related disaster occurred in cities during daily life activities. Moreover, many of the victims were people over 60 years old, indicating that the occurrence of snow-related disaster is a problem especially for elderly people living in snowy regions.
3) Many of the snow-related disaster occurred during the removal of snow and ice from buildings or the removal of roof snow, and such accidents dramatically increased in years of heavy snowfall. Thus, the occurrence of snow-related disaster is greatly affected not only by meteorological conditions such as amount of snow-fall but also by residential area planning and by the construction design of individ-ual buildings.
4) It was found that, in contrast to the immediate increase in the number of snow-related traffic disaster following an increase in the amount of snowfall, the num-ber of snow-related disaster begins to increase at about 10-20 days after an increase in the amount of snowfall.

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In our country, large scale leisure facilities and condominiums were constructed from the middle of 1980. In the background of many condominiums construction, there were an increase of the free time and realization of the new life style.
In Yuzawa town, the resort condominiums were constructed from 1975, and 14, 840 rooms are now available. As a result of too many rooms, a lot of problems such as a land use problem, a landscape problem and traffic jam are caused.
The purpose of this study is to examine the increase measure of the resort condominiums. In this paper, the following items are analyzed:
(1)The understanding of the situation of utilization of the resort condominiums
(2)The analysis of the sale intention of the resort condominiums
(3)The image analysis for Yuzawa town as a resort town
(4)Countermeasures to increase the users by introducing the sightseeing passport

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