After the corridor of forest road networks have been planned with a computer-aided planning system, a detailed planning of the preliminary route of forest road, consequently, is required. At this stage, consideration should be taken for various parameters such as slope, construction cost, drainage, environmental impacts. However, the more in number of parameters there are, the more complicated the planning method. For detailed planning of the preliminary routes of forest roads especially in the private forests, a simple method with the least number of data is required. In this study, the network operation of GIS was applied to lay out the preliminary routes of forest roads in the mountainous forest. The network technique of ARC/INFO requires two parameters for its operation. In this study, the parameters assigned to lay out the preliminary route are composed of slope, road construction cost, and road length. The slope was derived from a Digital Elevation Model (DEM). Two methods of laying out the preliminary routes using the network technique were investigated. The first method, the site slope and length of road were used as the parameters; while, for the second method the site slope and construction cost of road were used. The site slope was used to control the movement of link from one arc, through the node, onto another arc. The length and construction cost of road were used to select the route of minimum length or minimum construction cost respectively. The results show that both methods resulted in similar shape and corridor of planned routes. By considering a required number of control parameters, it was shown that method I (site slope and road length) can be used as the control parameter more suitably than method II (the slope and construction cost) for laying out the preliminary routes of a forest road in a private forest.

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Forester thins out trees in order to increase the commercial value of the timber, therefore it is important to minimize the damage of forest stand by cable skidding operations. The purpose of this study is to make clear the relationships between the damages on forest stand and the profile indexes of terrain in the case of the thinning operations by a running skyline system using a small skidder mounted a yarder with tower. The more the horizontal intersection angle between the skyline and the maximum gradient line at the yarding trail or the more the volume of lateral skidded logs, the more pieces of trees were damaged by the skidding operations. And the less the vertical clearance between the ground and the skyline, the harder soil compaction occurred at the yarding trail by logs. It was not obvious that the area of scraped forest floor consist-ing of the litter, intermediate and humus layer related to the profile indexes of terrain using a linear regression method. On the discussion of the individual cases, it seemed reasonable to suppose that the area of scraped forest floor increased at the setting where the vertical clearance between the skyline and the ground was not enough for high skidding or the horizontal intersection angle between the skyline and the maximum gradient line was large. In conclusion, it follows from these results that the profile classification observed by the field survey is effective to design the location of cable cranes with considering to ensure the less damage of forest stands.

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A silvi-culture walking machine having the linear motion mechanism, outrigger legs, and variable body structure was designed and experimented on walking. The linear motion mechanism is easy to control the tip of leg. Therefore, control of legs and the body are simple. The outrigger legs are able to realize static walk by spreading out of safety zone. The combination of variable body structure and linear motion mechanism is able to keep in the safety zone of a shadow point of the center of gravity. This model was experimented by the 4 types of walking on flat terrain and on a sandy soil of 15 cm depth. As a result of the experiments, more safety gait was right-front, left-rear, left-front, right-rear, and outrigger legs. It was able to keep the roll and pitch angles within ±1°on a sandy soil. It was able to keep the roll angles within ±1°by controlling the body horizontal for the legs sinking in sand.

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We measured the physiological responses and the unpleasant feeling of 8 men under 6 kinds of impact noise (75 dB at subjects' ears) with different frequency distributions. The α,β and θ-activity of Electroencephalograms (EEG), and the increasing rate and the coefficient of variation of R-R interval time (CV-RR) of heart rate were used to monitor the subject's physiological responses to 6 different noise distributions. As the results, the subjects' unpleasant feeling tended to increase with the noise with higher frequency distributions. The degree of the subjects' unpleasant feelings judged by 20 pairs of adjectives to 6 different noise distributions, comparing one basic noise, were analyzed by the SD method, and 5 factors (moderate, stable, heavy, rapid and qualitative feeling) were selected. Then, the subjects' unpleasant feelings were evaluated by the additivity-measure of the AHP method and 2 fuzzy measures (possibility and necessity measure) using the Choquet integral to the results obtained from the AHP method. It showed that the unpleasant feeling tended to increase with the noise with a higher frequency distribution. It was found that subjects tended to decrease the unpleasant feeling to the noise with a higher frequency distribution as "heavy and rapid" noise by possibility-measure, and to increase one as "moderate, stable and qualitative" noise by necessity-measure. Thus, it was found that both methods of evaluation by physiological responses (i.e., EEG and heart rate), and analysis of the sensory test by the AHP method and 2 fuzzy measures using the Choquet integral gave the same results, and that it was possible to obtain a detailed evaluation of human response to the noise using 2 fuzzy measures.

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In the previous study, we had examined an operation system on a steep slope. In the present study, we have examined another operation system cooperated with a harvester and a forwarder working at a moderate slope. With a program that is completed by authors by means of personal computer's language GPSS/PC^<TM>, a simulation has been done for the best operation condition, and the best combination of the machines on a moderate slope. As an operation method one can select various ones such as various thinning processes and a clear cutting one, but herewith we have only selected the thinning process, for example, on a Japanese larch plantation so that practical data could be obtained easily. The results obtained from the simulation showed that: (1) This system would be most effective and have no waiting time when the operation efficiency of the forwarder was approximately 85% of that of the harvester. (2) However, once the efficiency of the forwarder does not meet the need, the former have to wait for the operation of the latter, and at this event we would like to start the former later rather than start them simultaneously in order to get an overall good efficiency of the whole operation system. (3) The operation efficiency of the forwarder correlated positively with its loading capacity, cutting rate, and tree age, and also correlated negatively with the shape and dimension of cutting area and running distance to a landing, as well.

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