In this paper, we generalize the models used by MacKay [1] in his analysis of evolutionary strategies that are based on sexual, rather than asexual, reproduction methods. This analysis can contribute to the understanding of the relative power of genetic algorithms over search methods based upon stochastic hill-climbing, e.g. [2], [3].

conclusions glenohumeral joint reduction with reconstruction of the humeral head seems to be possible even in a neglected locked posterior shoulder fracture-dislocation. if the depressed osteochondral fragment is still spheric, signs of the avascular necrosis are absent on ct, and mal:union: of the fragment has occurred, it is quite possible to reconstruct the head. although results of the case...

Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the...

A floristic and ecological study of bryophytes and macrolichens in different lowland rain forest types around Mabura Hill, Guyana, South America, yielded 170 species: 52 mosses, 82 liverworts and 36 macrolichens. Lejeuneaceae account for about 30% of the species and are the dominant cryptogamic family of the lowland rain forest. Special attention was paid to the flora of the forest canopy, by u...

Unlike green sand, chemically bonded sand cannot be used again and again without reclamation because in this system, the mixed sand gets it`s strength through chemical reaction which is irreversible in nature. Each sand particle is coated with this reacted chemical, which behaves like an inert element after usage once. This inert coating also called “Dead” binder needs to be removed from the us...

We present an interactive sand art drawing system using one RGB-D sensor, such as Kinect. Our system supports the common sand drawing functions, such as sand erosion, sand spilling, and sand leaking. To use hands to draw virtual sand on a drawing plane, we design four key gestures which enable drawing manipulation actions for sand. The basic idea is that the gesture of one hand controls the dra...

This experiment compared the effects of sand and straw bedding in free stalls on resting time, cleanliness, hock injuries, and hoof health of dairy cows and tested whether cow preferences for a bedding material depended on the familiarity with the material. A total of 52 dairy cows were kept either on straw bedded concrete stalls or sand stalls for at least 21 wk. The lying behavior was observe...

compared to quartz sand, the shear behavior of carbonate sand differs in  appearance, origin, and kind. carbonate sand is found mainly in the northern coast of the persian gulf and the oman sea. in this research, a comparison is made between the shear behavior of carbonate sand retrieved from the eastern region of the chabahar port, located north of the oman sea, and quartz sand obtained from f...