Algorithm for the stabilization of motion a bounding vehicle in the flight phase

The unsupported phase of motion of a multileg bounding vehicle is examined. An algorithm for stabilization of the angular motion of the vehicle housing by change of the motion of the legs during flight is constructed. The results of mathematical modelling of the stabilization process by computer are presented

Survey of arctic bird migration and staging areas at the White Sea, in the autumns of 1999 and 2004

Finnish Environment Institute organized two ornithological expeditions to the White Sea, between 21st September and 10th October 1999, and between 21st September and 10th October 2004. The main aim of these expeditions was to map the most important staging areas for the migrating arctic birds at the White Sea. Several internationally important staging areas were found at the White Sea. Transect line counts at sea showed that the densities of birds outside these areas were smaller. During the expeditions a lot of data collected about the migration, daily rhythm, directions and routes of the migration, intensity, timing and the age and sex of the birds. Clear differences between species were noticed in the dynamics, directions of routes and intensity. Some of the species migrate on a wide front and others follow the coastal lines. The expedition was carried out by vessel. Compared to aerial surveys, which are also used for mapping of staging areas, vessel is cheaper. Vessel surveys allow more time for observing for instance birds which are sensitive or few in numbers. On the other hand a vessel is slow and shallow areas, which are important staging areas for waterfowl, are inaccessible. Aerial surveys make it possible to cover large areas and to find the most important staging areas for arctic waterfowl

Algorithm for constructing the programmed motion of a bounding vehicle for the flight phase

The construction of the programmed motion of a multileg bounding vehicle in the flight was studied. An algorithm is given for solving the boundary value problem for constructing this programmed motion. If the motion is shown to be symmetrical, a simplified use of the algorithm can be applied. A method is proposed for nonimpact of the legs during lift-off of the vehicle, and for softness at touchdown. Tables are utilized to construct this programmed motion over a broad set of standard motion conditions

Density and distribution of the greater mole rat (Spalax microphthalmus) on the northern border of the area in a region of European Russia

There are few subterranean mammals in Russia. The aim of the paper is to study the distribution and abundance of greater mole rat in the local population. The characteristic of the local population of the greater mole rat (Spalax microphthalmus) on the northern border of the range with reference to geographical coordinates is given. Our research has been conducted in Republic of Mordovia (European Russia). The field studies were carried out in 2007-2019. The population density in Mordovia is from 2 to 6 individuals/ha. The number of greater mole rat is estimated at 190 individuals. There are 27 to 200 mounds per one hectare of registered area. The distance of the greater mole rat habitat in Mordovia is from 40 to 372 km from other populations of neighboring regions. It is revealed that animals in the region are confined to pastures and dacha areas. The population density of subterranean rodent populations, such as mole rats, is in equilibrium with the capacity of the environment in which they live. The results on the population density and the number of greater mole rats on the northern border of the species range indicate the oppression of the local population

Financial Aspects of Technological Concept for Energy Efficiency Enhancement during Stripper Wells Development in Tomsk Region

The issue of operating costs cutting in terms of falling oil prices on the world market actualizes the challenge to find technological solutions to reduce electricity consumption during well operation. This is especially important for stripped-wells of small deposits in Tomsk region. The correlation analysis between the cost of oil production, electricity, heat and fuel consumption during the extraction of one ton of oil allowed the authors to focus on the financial aspect of such technological solutions like periodic well operation in the Shinginskoye field as well as to recommend the application of this method at the other fields in Tomsk region

Surface Tension of Seawater

New measurements and a reference correlation for the surface tension of seawater at atmospheric pressure are presented in this paper. Surface tension of seawater was measured across a salinity range of 20 ⩽ S ⩽ 131 g/kg and a temperature range of 1 ⩽ t ⩽ 92 °C at atmospheric pressure using the Wilhelmy plate method. The uncertainty within measurements varied from 0.18 to 0.37 mN/m with the average uncertainty being 0.22 mN/m. The experimental procedures were validated with tests conducted on ACS reagent grade water and aqueous sodium chloride solutions. Literature data and present measurements were evaluated and a reference correlation was developed expressing surface tension of seawater as a function of temperature and salinity. The average absolute percentage deviation between measurements and the correlation was 0.19% while the maximum deviation was 0.60%.Center for Clean Water and Clean Energy at MIT and KFUPM (Project R13-CW-10