Preparation of monotectic alloys having a controlled microstructure by directional solidification under dopant-induced interface breakdown

Monotectic alloys having aligned spherical particles of rods of the minor component dispersed in a matrix of the major component are prepared by forming a melt containing predetermined amounts of the major and minor components of a chosen monotectic system, providing in the melt a dopant capable of breaking down the liquid solid interface for the chosen alloy, and directionally solidfying the melt at a selected temperature gradient and a selected rate of movement of the liquid-solid interface (growth rate). Shaping of the minor component into spheres or rods and the spacing between them are controlled by the amount of dopant and the temperature gradient and growth rate values. Specific alloy systems include Al Bi, Al Pb and Zn Bi, using a transition element such as iron

Civil Rights-State Action-Customs Having the Force of Law by Virtue of Persistent Practices of State Officials Constitute State Action. Adickes v. S. H. Kress and Company (U.S. 1970)

This recent case discusses Adickes v. S. H. Kress and Company (U.S. 1970)

Ecology and management of the mourning dove, Zenaidura macroura (Linn.), in Cass County, Iowa

Decrease of the mourning dove, an important game bird of the United States, has been noted recently in eastern and southern states. In Iowa, the dove is among the commonest of breeding birds, and observations in Cass County, Iowa, during 30 months of 1938, 1939 and 1940 revealed that the county production was high, averaging an estimated 200,000 young yearly from 73,000 adults. About 2 percent of the summer residents is believed to have wintered in the county. Detailed investigations at Lewis, at 14 farmyards and at 6 other habitat types, brought under observation nearly 4,000 nests. The preferred types of trees were elms and conifers. The average success of nestings was 50 percent, an average of 55 percent of the eggs was hatched, and an average of 82 percent of young left the nests yearly. The peak of nesting activity came during the middle of June, followed by a slump in August and a slight increase in the fall. The robin-dove relationship was greatly of advantage to the dove in nesting

Resolving depth measurement ambiguity with commercially available range imaging cameras

Time-of-flight range imaging is typically performed with the amplitude modulated continuous wave method. This involves illuminating a scene with amplitude modulated light. Reflected light from the scene is received by the sensor with the range to the scene encoded as a phase delay of the modulation envelope. Due to the cyclic nature of phase, an ambiguity in the measured range occurs every half wavelength in distance, thereby limiting the maximum useable range of the camera. This paper proposes a procedure to resolve depth ambiguity using software post processing. First, the range data is processed to segment the scene into separate objects. The average intensity of each object can then be used to determine which pixels are beyond the non-ambiguous range. The results demonstrate that depth ambiguity can be resolved for various scenes using only the available depth and intensity information. This proposed method reduces the sensitivity to objects with very high and very low reflectance, normally a key problem with basic threshold approaches. This approach is very flexible as it can be used with any range imaging camera. Furthermore, capture time is not extended, keeping the artifacts caused by moving objects at a minimum. This makes it suitable for applications such as robot vision where the camera may be moving during captures. The key limitation of the method is its inability to distinguish between two overlapping objects that are separated by a distance of exactly one non-ambiguous range. Overall the reliability of this method is higher than the basic threshold approach, but not as high as the multiple frequency method of resolving ambiguity