著者
Honglin HE Takashi OGUCHI Ruigi ZHOU Jianguo ZHANG Sen QIAO
出版者
The Association of Japanese Geographers
雑誌
Geographical review of Japan, Series B (ISSN:02896001)
巻号頁・発行日
vol.74, no.2, pp.187-198, 2001-12-01 (Released:2008-12-25)
参考文献数
18

The damage caused by the 1996 Lijiang earthquake in China was analyzed using Geographic Information Systems (GIS), Data for the Lijiang district were collected from the local government offices and were converted into GIS data layers. The damage ratio of houses, seismic intensity and the occurrence of casualties were mapped. The results show that the distributions of seismic intensity and the damage ratio of houses reflect the occurrence of thick alluvium and the structure of fault systems.
著者
花井 友美 小口 孝司 Tomomi HANAI Takashi OGUCHI
雑誌
學苑 = GAKUEN (ISSN:13480103)
巻号頁・発行日
vol.772, pp.1-10, 2005-02-01

Computer-dating, the meeting with others through the Internet, has proliferated for several years. The aims of this study are (a) classifying the purposes of computer-dating usage and (b) investigating the computer-dating users' behaviors and interpersonal relationships (i.e., how many people they contact, how much they are satisfied, and how long they continue to use it). Then it might be expected that (c) they are related with the level of the users' loneliness. Twenty-six participants, who have used computer-dating, were recruited through the Internet and completed questionnaires that examined their loneliness, purpose of computer-dating usage and items regarding usage of computer-dating. The results showed: (1) there were two different types of purposes, "making relationship" and "conversation," and (2) the more loneliness they had, the higher "making relationship" purpose they had. In addition, (3) the purpose for "making relationship" promoted the later interpersonal behaviors on computer-dating.
著者
Keiichi KATSUBE Takashi OGUCHI
出版者
The Association of Japanese Geographers
雑誌
Geographical review of Japan, Series B (ISSN:02896001)
巻号頁・発行日
vol.72, no.1, pp.63-72, 1999-06-30 (Released:2008-12-25)
参考文献数
27
被引用文献数
16 21

Previous research indicated that the average slope angle in Japanese mountains tends to increase with increasing altitude. This paper examines the details of the change for the three ranges of the Japan Alps using 2.25''×1.5'' (ca. 50×50m) DEMs provided by the Geographical Survey Institute of Japan. Altitudinal changes in profile curvature were also analyzed. The results indicate that the ranges can be divided into three altitude zones. Zone 1 (< ca. 1, 000m) is characterized by an increase in mean and modal slope angle with altitude as well as concave slope profiles. Zone 2 (ca. 1, 000 to 2, 800m), which occupies the broadest area of the ranges, is characterized by increases in the mean slope angle with increasing altitude, but the modal slope angle is around 35 degrees regardless of altitude. The modal profile curvature is also stable around null throughout the zone, reflecting straight slope profiles. The ratio of hillslopes with an angle of ca. 35 degrees to all hillslopes increases with increasing altitude, suggesting that hillslopes converge into a characteristic form after long-term erosion. Zone 3 occurs in narrow zones near mountain summits (> ca. 2, 800m) where hillslopes are subjected to periglacial actions, wind erosion and Pleistocene glacial erosion. This zone is characterized by the decreasing slope inclination with altitude and convex slope profiles.
著者
Zhou LIN Takashi OGUCHI DUAN Fengjun
出版者
The Association of Japanese Geographers
雑誌
Geographical review of Japan, Series B (ISSN:02896001)
巻号頁・発行日
vol.72, no.2, pp.181-192, 1999-12-01 (Released:2008-12-25)
参考文献数
9
被引用文献数
1 1

Using GIS data, the effects of topography and climate on the large-scale distribution of population and soil were examined for 20 regions in East and Southeast Asia. The results indicate that relationships between topography and population vary according to climate. Although population density decreases with increasing terrain height and slope in most regions, this correlation does not hold true in desert regions such as Mongol and western China, because the locations of residential areas highly depend on the local availability of water resources. In cold regions including the Tibetan Plateau, the effect of height on population density surpasses the effect of slope, because extremely cold highlands are unfavorable for living. In contrast, some tropical or sub-tropical highlands are densely populated reflecting a climate better than that in lowlands. The large-scale distribution of soil types is strongly dependent on climate which affects weathering and pedogenesis processes, especially in arid or tropical regions. In temperate and sub-tropical regions, however, topography also plays a significant role in determining soil distribution.
著者
Takashi OGUCHI
出版者
The Association of Japanese Geographers
雑誌
Geographical review of Japan, Series B (ISSN:02896001)
巻号頁・発行日
vol.68, no.2, pp.151-165, 1995-12-31 (Released:2008-12-25)
参考文献数
38

In Japanese mountains, erosive force markedly increased after the Pleistocene-Holocene transition because of increased heavy rainfall, resulting in channel incision along hillslope hollows and tributaries. This paper investigates the process of channel incision in the Matsumoto Region of central Japan based on morphometry. Attention is directed toward the effects of headward erosion and channel widening on channel expansion. Channel length and area occupied by channels were measured for more than eight hundred 500×500m morpho-. metric samples taken from eight watersheds. Analyses of channel length and channel area based on location-for-time substitutions have revealed that channels develop through two stages. At the early stage, the channel length-channel area relation is expressed by a power function. The function indicates that headward erosion contributes to about 80 percent of the channel-area increase whereas channel widening contributes to about 20 percent. At the late stage, channel length tends to be unchanged owing to the stabilization of channel heads, and channel widening solely accounts for the channel-area increase. The stabilization of channel heads occurs when channel length has reached about 80 percent of total valley length. The ratio of 80 percent most likely represents a limit of channel elongation determined by the geomorphological and hydrological threshold of erosion.