Yamamoto M.,Hokkaido University |
Sai H.,Hokkaido University |
Sai H.,Hitachi Advanced Systems Corporation |
Chen M.-T.,National Taiwan Ocean University |
Zhao M.,Ocean University of China
Climate of the Past | Year: 2013
The response of the East Asian winter monsoon variability to orbital forcing is still unclear, and hypotheses are controversial. We present a 150 000 yr record of sea surface temperature difference (ΔSST) between the South China Sea and other Western Pacific Warm Pool regions as a proxy for the intensity of the Asian winter monsoon, because the winter cooling of the South China Sea is caused by the cooling of surface water at the northern margin and the southward advection of cooled water due to winter monsoon winds. The ΔSST showed dominant precession cycles during the past 150 000 yr. The ΔSST varies at precessional band and supports the hypothesis that monsoon is regulated by insolation changes at low-latitudes (Kutzbach, 1981), but contradicts previous suggestions based on marine and loess records that eccentricity controls variability on glacial-interglacial timescales. Maximum winter monsoon intensity corresponds to the May perihelion at precessional band, which is not fully consistent with the Kutzbach model of maximum winter monsoon at the June perihelion. Variation in the East Asian winter monsoon was anti-phased with the Indian summer monsoon, suggesting a linkage of dynamics between these two monsoon systems on an orbital timescale. © Author(s) 2013. CC Attribution 3.0 License.
Nagashima K.,Hitachi Advanced Systems Corporation |
Yamada K.,Hitachi Advanced Systems Corporation |
Tadano A.,Hitachi Advanced Systems Corporation
Hitachi Review | Year: 2013
OVERVIEW: A driverless Antarctic tractor system was developed in response to a request from the National Institute of Polar Research (an Inter-University Research Institute Corporation Research Organization of Information and Systems) for a vehicle that could be used to transport supplies from the coast to the interior of the Antarctic continent. In addition to conventional operation by a driver, the system is also capable of automatically trailing another vehicle using a combination of autonomous driving and positioning information from a variety of sensors, including gyroscopes and GPS positioning data transmitted from the driver-operated vehicle. The aim for the future is to improve the efficiency of goods transportation in the Antarctica through the adoption of fully automatic systems, such as operating a number of tractors automatically in a convoy, or converting driveroperated vehicles to driverless operation.