The major disadvantage of the new grass cutting system equipped with a fixed blade is due to the weight of the cutting unit. To overcome this disadvantage, we designed a perforated fixed blade, weighing about 315g, as against the conventional fixed blade of about 385g. The perforated blade was used for cutting the grass in different density to measure the operators heartbeat rate, O₂ consumption and mowing efficiency. Thereby, an increase in the heartbeat rate, heartbeat rate and O₂ consumption per mowing area were obtained. The experimental data, thus obtained, were compared with the data obtained while operating the conventional fixed blade and an ordinary blade, to check the degree of physical strain on the operator. The major results are summarized as follows.
1) On the testing site (1) (Lolium Multiflorum Lam, : weighing about 1.4kg live), the site (2) (Sorghum Vulgare Per. and Digitari Adscendens Henr. mixed, : about 2.9kg) and the site (3) (Lolium Multiflorum Lam.: about 5.5kg), the heartbeat rate and the increase in the heartbeat rate while operating the perforated fixed blade were lower than those of the conventional blade.
2) The ratio of heartbeat increase while operating the perforated fixed blade was 0.94 on the testing site (1), 0.99 on the testing site (2), and 0.97 on the testing site (3). There was little difference between the three. On the testing site (2) and (3), cut grasses left on the blade had to be removed with extra labor, undermining the effect of the blade to lower the physical strain on the operator. On the testing site (1), removal of the grass off the blade was not necessary. The difference in the weight of the cutting unit affected the physical strain on the operator. In other words, the perforated fixed blade works effectively to reduce the physical strain in cutting the grasses in low density.
3) In making a comparison of degrees of the physical strains caused by using the blades of different working efficiency, on the different testing sites with the grass of different density, we judged it appropriate to use the ratio (physiological working efficiency) of the average heartbeat rate per minute in cutting operation against the cutting area per minute (working efficiency: m²/min.). We obtained the ratio of the physiological working efficiency of the perforated fixed blade against that of the conventional fixed blade. The ratio was about 8% on the testing site (1), about 10% on the site (2) and about 3% on the site (3). The results shows that perforated fixed blade worked positively to reduce the physical strain on the operator.
4) Ordinary cutting blade, regardless of the kind of grass to be mowed and the weight of the blade, had a larger physiological working efficiency than the perforated fixed blade because of large gyroscopic couple. Increased gyroscopic couple made it difficulty to operate the machine and increased physical strain on the operator.

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In order to mechanize planting operations in the cultivation of sugar cane, a one-row tractor-mounted planter incorporated a feeding mechanism of two buds-seedcane was developed and the planter performance was examined for practical use. The results were follows;
1) With planting speeds between 23m/s and 63m/s, the proper planting rates were between 94% and 98%.
2) The planting rates of plural seedcane were between 1% and 2% at any planting speed.
3) The planting rates of slant seedcane were between 1% and 4% and increased slightly with increasing planting speed.
4) The planting spaces were between 25cm and 27cm at any planting speed.
5) The planting depths were between 18cm and 21cm at any planting speed and therefore the accuracy is far better than manual operation.
6) The performance of developed machine at the planting speed of 52cm/s was 98.2% actual planting rate (plural seedcane 1.3% and slant seedcane 3.0%), spacing 25.6cm, depth 20.6cm and actual planting capacity of 10.1a/h. This capacity is about 11 times of manual operation capacity.
7) The damage and wrong planting pause which could hinder sprouting of the two buds-seedcane were not recognized and therefore the planter development can be considered as one of the breakthrough in sugar cane planting mechanization.
8) Further research is required in preparations of two buds-seedcane, construction of the holding box and design of the durable feed roll.

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Reduction on Workload of the Farmer's Family Producing Tulip Bulbs (II) The Characteristics of the Labor in a Diversified Farming of Tulip Bulbs and Paddy Rice.
The purpose of this paper was to obtain some fundamental data for reducing the workload by clarifying the characteristics inclding physical and mental burden of the labor in a diversified farming of tulip and paddy rise. The obtained results were as follows.
1) In tulip bulbs farming, there were two peaks in working time. First is term from June to July for harvesting, processing and shipping, and second is the term in October for bulb planting. The similar patterns were observed in transplanting and harvesting in paddy rice farming, but the two peaks didn't overlap each other.
2) The two peaks of working time in a diversified farming of tulip bulbs and paddy rice gave an influence on daily life time out of labor. Especially working interval time in harvesting of tulip bulbs was the shortest in a year and sleeping time was also the shortest.
3) Required working time (minute/ha) in tulip bulbs farming was 10.6 times and 26.4 than that in planting of paddy rice and harvesting of paddy rice, respectively. The phenomenon was explained by the difference of mechanized levels in two farmings. To promote mechanization in tulip bulbs farming is important in the future.

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