This method for estimating the complicated topography properties is described on the basis of a method of terrain index by using slope-gradient distribution, that was developed by Hori (1989). Elements characterizing the complicated topography property were investigated, that were the standard deviation of the azimuth of maximum hill-site slope C_B, density of valleys and ridges ρ_D and slope-fold curvature D_a defined from the rate of irregularity of the direction in maximum gradient at the measuring points. By comparing of the function D_a with C_B and ρ_D, the technical difficulties of mechanized logging operations were changed, when the function D_a was about 0.6 and 0.9. As the result, the complicate topography index F_D, that was conducted by using the slope-fold curvature distribution, was proposed. This method was applied to the data of 120 area, in which unit area of about 5 ha. (including almost 80 measurement points (25m×25m)) is available. The slope-fold curvature distribution was well expressed by simple uniform equation. The equation for the determined F_D and D_a are described. Also the value of the standard deviation σ_X, that is characterizing slope-gradient distribution-curves, is closely related to F_D or W_2 (the expectation of the complicated topography deriving from mean slope-gradient in unit area). The σ_X was shown in the ellipse equation, that was composed of W_2 or F_D.

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The model estimating potential slope failure using the fuzzy integral was applied to the four areas of a private forest in Gifu prefecture, Kyoto University forest in Wakayama, a public forest road in Shiga and Oita prefecture. The discriminant ratios by using the quantification 2 method using fixed category scores decreased very much when applied to these four areas. On the other hand, they did not decrease so much when the fuzzy integral was used. As a result, the discriminant ratios using the quantification 2 method and the fuzzy integral could be estimated at 62.3%, 69.8% for cutting slopes and 74.3%, 75.5% for banking slopes, respectively. In addition, the degree of importance to each factor could be changed and also the effective factors could be selected according to the coefficients of necessity when the fuzzy integral was used.

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We measured the physiological responses of 17 men in simple calculation work under 5 kinds of light floor-impact sounds with different reverberating time and 3 kinds of sound level, that is, 75, 80 and 85 dB (A). As the results, numbers of correct answers of simple calculation tended to decrease with increasing sound levels. And, with increasing sound levels, EEG θ-activity tended to increase, and EEG β-activity, the increasing rate of average heart rate to average resting level and CV-RR tended to decrease. Moreover, as the results of analyses of different reverberating time by the rate of each physiological response under noise (75 dB(A)) to non-noise, with extremely long reverberating time and short one, EEG β-activity and CV-RR tended to decrease, and EEG θ-activity tended to increase. Thus, the human concentration to simple calculation work tended to decrease with increasing sound levels, and with extremely long reverberating time and short one.

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We have already developed a simulation program with the use of large frame computer's language : GPSS and examined the optimum condition of a yarding operation system with this program, as an example of its application. In this study, this program was converted into a generalized one with parsonal computer's language : GPSS/PC^<TM> which easy and wide use could be expected. And yarding operation systems on a steep slope (combination and relative location of machines) was examined. The results of the simulation indicated that, in the clear cutting operation on a steep slope, the optimum system was the combination of a road-hauling by a skidder and log-processing by a processor with yarding by a mobile tower yarder. The efficiency of this system was best when the distance between a tower yarder and a processor was closer than 120 m, and the each distance between rigged up cable lines of a yarder was around 20 m-40 m.

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The temperature and humidity inside forestry-workers clothes for brush cutting were investigated using three different materials. These clothes were made of polyester/cotton woven fabrics of multi layered yarn, cotton fabrics, and linen fabrics. The measurements were conducted in a climate chamber. Inquires were also made with subjects about the feeling of the clothes. Results show that there were hardly any differences in temperature and humidity inside clothes among the 3 kinds of materials. There were also no significant differences in the questionnaires of the feeling of the clothes. In this study we used materials which were suited as work clothes for summer brush cutting. The differences among these materials were small. It is necessary to consider the design of forestry-workers clothes for brush cutting.

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