Nacrtak Mechanized felling was introduced in Slovenia at the beginning of this decade, and before that Slovenian forestry relied on motor manual felling and tractor skidding or cable crane yarding. In this research we are dealing with wood forwarding. Model skidding maps were built, using terrain classification and decision support systems for forwarders and tractor trailers. The purpose of thi...

BACKGROUND Indian tractor drivers operate their tractors and other implements/equipment in an environment which can have extreme temperatures and high level of suspended particulate matter. In addition, Indian tractors do not have adequate vibration and noise attenuating designs features. This cross-sectional study compares the hearing status of tractor driving farmers (TDFs) (study group) and ...

Operator exposure to high levels of whole-body vibration (WBV) presents risks to health and safety and it is reported to worsen or even cause back injuries. Work activities resulting in operator exposure to whole-body vibration have a common onset in off-road work such as farming. Despite the wide variability of agricultural surface profiles, studies have shown that with changing soil profile a...

Trailer reversing is a problem frequently considered in the literature, usually with fairly complex non-linear control theory based approaches. In this paper, we overview our simple method for stabilizing a tractor-trailer system to a trajectory based on the notion of controlling the hitch-angle of the trailer rather than the steering angle of the tractor. The performance of this control method...

In this article we describe the formulation of null geodesics as null conformal geodesics and their description in the tractor formalism. A conformal extension theorem through an isotropic singularity is proven by requiring the boundedness of the tractor curvature and its derivatives to sufficient order along a congruence of null conformal geodesic. This article extends earlier work by Tod and ...

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...