25 research outputs found
Problem of the gyroscopic stabilizer damping
The gyroscopic stabilization of the vibro-isolation system of an ambulance couch is analyzed. This paper follows several previous papers, which concern the derivation of the complete system of appropriate differential equations and some analyses were provided there, as well. It was supposed that mass matrix, stiffness matrix and gyroscope impulse-moment remain constant and the stability of equilibrium state was solved according to different alternatives of the damping and of the radial correction. Little known theorems of the stability were used there. With respect to these theorems, vibro-isolation systems can be classified according to odd or even number of generalized coordinates
Ecology of the silvery mole-rat (\kur{Heliophobius argenteocinereus} in its natural habitat
NON-LINEAR DAMPING IN THE SYSTEM OF TWO-AXIS GYROSCOPIC STABILIZER
This paper tackles the reasons for the application of the shock absorbers in the mechanical system of the two-axis gyroscopic stabilizer. The procedure of choice of the suitable damping torque characteristics based on the numeric simulations is proposed as well
Transient properties of a magnetorheological damper - Discussion to the paper by Seung-Bok et al.: "H∞, control performance of a full-vehicle suspension featuring magnetorheological dampers"
A discussion in terms of dynamic properties of a magnetorheological damper is lead to those in the denoted paper. Results of experimental evaluation of the properties of a commercially available magnetorheological damper are presented. A possibility of use of the damper in practical applications is also considered
Data from: Parentage analysis of Ansell's mole-rat family groups indicates a high reproductive skew despite relatively relaxed ecological constraints on dispersal
To better understand evolutionary pathways leading to eusociality, interspecific comparisons are needed, which would use a common axis, such as that of reproductive skew, to array species. African mole-rats (Bathyergidae, Rodentia) provide an outstanding model of social evolution because of a wide range of social organizations within a single family; however, their reproductive skew is difficult to estimate, due to their cryptic lifestyle. A maximum skew could theoretically be reached in groups where reproduction is monopolized by a stable breeding pair, but the value could be decreased by breeding-male and breeding-female turnover, shared reproduction and extra-group mating. The frequency of such events should be higher in species or populations inhabiting mesic environments with relaxed ecological constraints on dispersal. To test this prediction, we studied patterns of parentage and relatedness within 16 groups of Ansell's mole-rat (Fukomys anselli) in mesic miombo woodland. Contrary to expectation, there was no shared reproduction (more than one breeder of a particular sex) within the studied groups, and proportion of immigrants and offspring not assigned to current breeding males was low. The within-group parentage and relatedness patterns observed resemble arid populations of ‘eusocial’ Fukomys damarensis, rather than a mesic population of ‘social’ Cryptomys hottentotus. As a possible explanation, we propose that the extent ecological conditions affect reproductive skew may be markedly affected by life history and natural history traits of the particular species and genera
Activity of radio-tracked mole-rats and associated environmental conditions during the 24-h day.
<p>Mean ± SD is presented for the four subordinate (non-breeding) family members. Black bars indicate the dark phase of the day.</p
Fukomys_anselli_genotypes
The genotypes of nine microsatellite loci obtained using the fragment analysis (ABI PRISM 3130) and scored using th GeneMapper 3.7. For each individual, its ID, sex, reproductive status, weight and group membership is shown