Workspace Analysis of the Orthoglide using Interval Analysis

International audienceThis paper addresses the workspace analysis of the orthoglide, a 3-DOF parallel mechanism designed for machining applications. This machine features three fixed parallel linear joints which are mounted orthogonally and a mobile platform which moves in the Cartesian x-y-z space with fixed orientation. The workspace analysis is conducted on the bases of prescribed kinetostatic performances. The interesting features of the orthoglide are a regular Cartesian workspace shape, uniform performances in all directions and good compactness. Interval analysis based methods for computing the dextrous workspace and the largest cube enclosed in this workspace are presented

Offspring Survival in the Demoiselle Crane \u3ci\u3eGrus virgo\u3c/i\u3e in Mongolia

The breeding performance of nine breeding pairs of the Demoiselle crane Grus virgo has been investigated in Takhin Tal, Mongolia, in order to get information about their breeding density as well as the survival rate of the juveniles. To this end, the nests and the offspring have been monitored from hatching up to the age of about two months in order to get information about their survival rate. All pairs settled within a distance of about 2 km to the only river in the area, resulting in a density of about 0.6 couples per km. The number of surviving juveniles decreased to the level of 56 % until about the age of 50 days and mid-August, respectively. Afterwards, it remained stable. Provided there are no significant changes from one year to another the data indicate the time of the year after which offspring mortality becomes negligible. These observations allow estimating reliably the seasonal population size as well as the breeding success based on a few counts only

Nestling Food in the Desert Wheatear \u3ci\u3eOenanthe deserti\u3c/i\u3e in the Dzungarian Gobi, Mongolia

The quality and size of nestling food of the Desert Wheatear Oenanthe deserti ssp. atrogularis were investigated in the spring of 2001 in the Dzungarian Gobi in Mongolia. Data are based on observations of nine pairs. Nestling food consisted of several taxa caught on the ground and in the air. Diptera, Coleoptera larvae, and Hymenoptera were the most frequent prey, that is, they contributed 17 to 30% of all food items each. The food composition changed with nestling age and season. Food item size decreased with date. A higher proportion of multiple prey loadings were brought to nestlings in the second half of the season than in the first half. Prey items were significantly smaller in multiple prey loadings than in single prey loadings, but as a whole, multiple prey loadings were larger than single prey loadings. Despite the increase of the proportion of multiple prey loadings in the second half of the season compared with the first half, the loading size decreased with time. Presumably, large, profitable prey became rarer with the ongoing season. This may have caused the parents’ feeding effort to increase and prevented them from starting regular second broods

Erkennung sehr geringer Mengen von Ammoniak in Wasser

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