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The ability of a newly developed carriage equipped with a remote control lock and self line extraction system manufactured
by Oikawa motors Co., Ltd. was analyzed. The study investigated the reduction of the work load of the choker setter in the
haul line-pulling out process of a cable logging system by a mobile tower yarder. The main objective was to compare the walking
time, pulling out time, and the tension force using the three types of cable setting method, a running skyline with a simple
carriage, a fixed skyline with a simple carriage and a fixed skyline with a newly developed carriage. The measuring of haul
line pulling out was conducted on different slope gradients at different distances from the tower spar by four choker setters.
The study showed that choker setters could reduce the force exerted by about 33%, and a decrease in the heart beat rate of
12%, when using the fixed skyline with the newly developed carriage as opposed to the running skyline with the simple carriage.
The fixed skyline with the newly developed carriage resulted in more pulling speed than the running skyline with the simple
carriage on the slope gradient of over 2° and the fixed skyline with simple carriage on the slope gradient of over 7°. With
the newly developed carriage the pulling tension, time and heart rate are lower, when the haul line is pulled out. Thus it
can be concluded that the new carriage is more productive than the simple carriage in the line pulling out process. 相似文献
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We hypothesized that northern and northeastern Thai populations of Merkus pine (Pinus merkusii Jungh. et de Vriese), which differ in the duration of their grass stage and which originate from slightly different climates in terms of water availability, differ in their gas exchange characteristics. We compared CO(2) exchange response to irradiance, diurnal regulation of leaf conductance within a 10-day period and structural properties among the populations. We used a model, which is based on the concept of optimal stomatal regulation, to analyze CO(2) exchange and transpiration rates. The two geographical groups did not differ in CO(2) exchange response to irradiance, diurnal transpiration, or water use. Mean stomatal length was significantly greater in the northeastern population than in the northern populations, but stomatal frequency did not differ among populations. First-year shoot growth and dry matter production, allocation of nitrogen to needles and root:shoot ratios were similar in the two geographical groups. Genotypic variation in the duration of the grass stage was not reflected in variation in gas exchange, indicating that the grass stage is an adaptation to more site-specific conditions. The modeled response of CO(2) exchange rates to irradiance fitted well the rates measured under laboratory conditions. The transpiration model, which utilized maximum leaf conductance and other parameters derived from the CO(2) exchange measurements, also fitted well the transpiration rates measured in a greenhouse under changing environmental conditions. 相似文献
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