A ship moving steadily forward in shallow water of constant depth h is usually subject to downward forces and hence squat, which is a potentially dangerous sinkage or increase in draft. Sinkage increases with ship speed, until it reaches a maximum at just below the critical speed p gh. Here we use both a linear transcritical shallow-water equation and a fully dispersive Ž nite-depth theory to d...

We motivate and analyze a reaction-advection-diiusion model for the dynamics of a phytoplankton species. The reproductive rate of the phytoplankton is determined by the local light intensity. The light intensity decreases with depth due to absorption by water and phytoplankton. Phytoplankton is transported by turbulent diiusion in a water column of given depth. Furthermore, it might be sinking ...

A near-infrared spectroscopic method and measurement system for moisture depth profiling is presented in this thesis. The measurement system is based on a fibre-optic light source and probes, and a hyperspectral imaging spectrograph. The probes feature six different measurement geometries, including a specular reflection measurement, and diffuse reflection and transmission measurements, all of ...

We motivate and analyze a reaction-advection-di usion model for the dynamics of a phytoplankton species. The reproductive rate of the phytoplankton is determined by the local light intensity. The light intensity decreases with depth due to absorption by water and phytoplankton. Phytoplankton is transported by turbulent di usion in a water column of given depth. Furthermore, it might be sinking ...

A catadioptric stereo system has been developed for depth perception. The system uses two sets of planar mirrors to create two virtual cameras. A design procedure is presented with the aim of building a compact assembly. This has resulted in an inexpensive and compact system that achieves a depth resolution of 5.8 cm at a working distance of 2 m.

soil detachment is known as an important process in soil erosion and its quantification is necessary to establish a basic understanding of erosion. this study was carried out to find the best flow erosivity indicator(s) for predicting detachment rate at low slopes. for this purpose, 12 experiments including 6 flow discharges (75, 100, 125, 150, 175 and 200 ml/s) and 2 slope gradients (1.5 and 2...

We have developed an x-ray photoelectron spectrometer system which combines an adjustable grazing incidence angle source with reflected beam detection. When operated about the critical angle, this combination permits a variation of the x-ray penetration depth which can be monitored by means of the reflectivity. At angles of incidence less than the critical angle, the sampling depth of the photo...

The objective of this paper is to study the impact of depth perception and movement freedom on learning surgical tasks by novice subjects using new laparoscopic technology.

abstract although many studies have been carried out about dam break, this phenomenon still is one of the most important issues in the field of hydraulic engineering due to its hazards to human societies. predicting the critical conditions including coincidence of flooding and dam break indicates more field studies requirement. in this research the mutual effects of coincidence of negative surg...