@article{oai:tokyo-metro-u.repo.nii.ac.jp:00002874,
 author = {ノガミ, ミチオ and Nogami, Michio},
 issue = {25},
 journal = {Geographical Reports of Tokyo Metropolitan University},
 month = {},
 note = {In the present paper, the author intends to summarize his investigations on flume experiments and computer simulations of river profile development, focusing his attention on characteristics common to two simulators, flume and computer. The concentration of sediment to water discharge is set by a sand feeder and a water flow regulator. In the case of the computer simulation the sediment flux is given as the upstream boundary condition. As the flux is proportional to the slope, the boundary condition is defined by the slope. The downstream boundary condition is given by water level in the both cases, with some modification at performance of the simulation. A type of diffusion equation is introduced to describe transportation of sediments. This procedure is not required for the flume experiments, because flowing water carries sediments spontaneously. The fundamental equation is as follows: ∂u/∂t=∂/∂x{ke^＜rx＞∂u/∂x} where u is height of the river profile at point x and time t, k and r are constants. The r is an index expressing how sediment decreases downstream in size. The dynamic equilibrium state appears after sufficient time elapsed in the flume and also in the calculation result by computer. The steady solution of the equation above shows an exponential curve which is admitted widely to be the most adequate to longitudinal river profiles. In this equilibrium state the profile is determined by the independent external conditions derived from climate and/or sealevel. The change of external conditions makes fluvial landform develop to direction of a new equilibrium state determined by the new external conditions, and will result in formation of the alluvial plain or terracing.},
 pages = {195--211},
 title = {Simulation of evolutional process of longitudinal river profile using experimental flume and computer},
 year = {1990}
}