There is a well known one–parameter family of left invariant CR structures on SU(2) ∼= S. We show how purely algebraic methods can be used to explicitly compute the canonical Cartan connections associated to these structures and their curvatures. We also obtain explicit descriptions of tractor bundles and tractor connections.

TRACTOR is the TELRI Research Archive of Computational Tools and Resources. It features monolingual, bilingual, and multilingual corpora and lexicons in a wide variety of languages, as well as tools for language processing. TRACTOR is a key element of TELRI II, a panEuropean alliance of focal national language technology institutions with the emphasis on Central and Eastern European and NIS cou...

In Spain, there are more than 250,000 tractors built before 1980, when it became mandatory for all new tractors to be equipped with a rollover protective structure (ROPS). A similar situation is found in the European Union, but the situation is worse in the U.S. and in developing countries. Directive 2003/37/EEC establishes that tractors over 800 kg weight can be homologated by using the OECD s...

in iran, onion plants are currently broadcast over the majority of onion fields and weeding and harvesting are done manually by seasonal workers. at harvest time, 40 worker-days are required to onion dig just one hectare. this cost could be saved if the operation could be carried out by machine. rear-mounted diggers can only be implemented if 40 cm spacing between rows is allowed for each tract...

The aim of this paper and its prequel is to introduce and classify the irreducible holonomy algebras of the projective Tractor connection. This is achieved through the construction of a ‘projective cone’, a Ricci-flat manifold one dimension higher whose affine holonomy is equal to the Tractor holonomy of the underlying manifold. This paper uses the result to enable the construction of manifolds...

This paper aims to classify the holonomy of the conformal Tractor connection, and relate these holonomies to the geometry of the underlying manifold. The conformally Einstein case is dealt with through the construction of metric cones, whose Riemannian holonomy is the same as the Tractor holonomy of the underlying manifold. Direct calculations in the Ricci-flat case and an important decompositi...

In a tractor hydraulic/transmission oil contamination is a serious problem as it works in such environment, these contamination may be in different forms dust particles, water, oxidation & corrosion products ,wear metal particles. Metal wear particles plays a significant role in failure of hydraulic system such as jamming of control valve, worn out of sealing element etc. Removal of these metal...

The rollover accidents in the tractor semi-trailer are often fatal and many factors could cause the tractor semitrailer rollover. In this paper, a rollover prevention control method was proposed based on real-time calculation of rollover index. The vehicle Center of Gravity CG height from the ground is an important parameter in the rollover index and it is estimated through lateral acceleration...

Bates et al. extended the "tax-adjusted reSelf-employment taxes, "effective" marginal placement model" by incorporating the interactax rates, and discounting schemes which allow ton between taxes and inflation in their study. for alternative purchase and disposal dates of They found that inflation increased the magnimachinery are incorporated into the traditional tude of costs and generally ext...