Research on temperature under clothing using new materials while brush cutting was conducted. Two types of shirts were studied. One is a textile of yarn consisting of multi-layers of cotton and polyestel (worker's shirt A), and the other is a fine acrylic fiber knit (worker's shirt B). Temperature and absolute humidity under clothing were related to the temperature of the black bulb thermometer in the atmosphere. When perspiring, shirt A's permeability was obstructed, and the humidity increased. Shirt B has high levels of water absorption and permeability, but the thermal conductivity increased with an increase in perspiration. Shirts A and B were developed to improve comfortableness under ordinary outdoor conditions. Their shirts could not be fitted for high levels of pirspiration. However, the shirts will be able to display functions in cooling the body temperature through transpiration in cloudy and windy conditions or in low humidity and windy weather.

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The cooling effect of the water-cooled vest which could hold cool water in suction-fibers was researched in order to decrease the physiological burden of cooling the body in high temperatures. By wearing a water-cooled vest, the relative humidity under clothing increased, but the temperature inside clothing was compelled to drop. Heat from the sun was intercepted and the effect of cooling continued for about 30 to 40 minutes. Even when wearing a shirt under the vest, a sufficient effect of cooling was obtained and comfortableness was improved by this type of undershirt. The water-cooled vest could reduce the heart rate both when working and rest. The reason for this could be considered as follows ; the necessity of the divergence of body heat was weakened, capillary vessels shrank, and surface blood flow decreased ; therefore, the physiological burden decreased. From the allowable corrected effective temperature for heat circumstances determined by Japan Association of Industrial Health, it was predicted that brush cutting was often dangerous in the Japanese summer. Therefore, the water-cooled vest would be effective especially for beginners, and experienced users in the early period of the brush-cutting seasons.

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Evaluation of the function and network layout of forest road using a GIS (Geographic Information System) was carried out at Tomizawa of Yamanashi Prefecture. The objective of this study is to evaluate the function and network layout of forest road using a GIS. The functions of road can be approximately evaluated as the connectivity function of road (CFR) and the accessibility function of road (AFR). The CFR expresses the ability of roads to connect with other road networks surround a town while the AFR expresses the ability of roads to access to the farther forest areas from a town. By dividing the road networks into tracks and sectors, the CFR and AFR could be used for planning of the forest roads because the location of potential function roads on the map could be found out, and could be fulfilled with the circular road networks to strengthen the accessibility and connectivity of roads. In addition, it was clarified that the vector-based GIS can be effectively used for preparing the road data according to the tracks and sectors, and for displaying the potential function roads on the map.

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Constructing forest-road networks is an important subject in promoting forestry mechanization. Forest-road networks are formed by 4 forest road standards : 1st, 2nd, 3rd grade and low-structure forest roads in Japan. The purpose of this study is to investigate the actual difference in degrees between the 3rd grade and the low-structure forest road. Comparisons were made using construction costs, cross sections of roads, geometric alignment, winding and adaptation to the similar function of HACK'S low in the basin. The average construction costs of low-structure forests road is about 1/2〜1/3 that of 3rd grade roads. Expensive costs in constructing of the 3rd grade were mainly explained by earth work and structure costs. In spite of this large cost differential between the road standards, there was little apparent difference in the values of geometric alignment, winding and coefficient of the function on HACK'S low. In the case of analysing the use of the quantification theory 2, the 3rd grade needed costly and a lot of earth work volume comparisons with low-structure forest roads though, the domination showed longitudinal slope to be gradual. These consequences suggest that the road standard for forest road networks in forestry should be formed by 1st, 2nd grade and low-structure forest road system from the economy point.

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