Jackknifing is uncontrolled braking of a truck-trailer combination which causes the trailer rotates relative to tractor and as a result extends to adjacent lanes, causing in many cases sever accidents. In this paper a simple two dimensional model is presented. The model includes parameters such as truck’s and trailer’s dimensions, coefficients of friction, masses, location of the load on the tr...

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...

field capacity, fuel consumption and drive wheel slippage in massey ferguson (mf399) tractor with standard and liquid ballasted (630 kg) axle load and at 4wd mode was evaluated and compared. the tests were conducted at the experimental station, college of agriculture, shiraz university, in a field with clay loam soil at average moisture content of 18% d.b. the experiment was of a randomized com...

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...

The turning capacity of the heavy-duty transport unit is understood as ability to make a turn when road tractor moving strictly along centerline road. In [1], mathematical model kinematics rotation superheavy train was presented. It later used assess influence various design parameters semi- trailers and their wheel control systems on unit. A shows movement real object, but it does not always r...

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...

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...

Parabolic geometries may be considered as curved analogues of the homogeneous spaces G/P where G is a semisimple Lie group and P ⊂ G a parabolic subgroup. Conformal geometries and CR geometries are examples of such structures. We present a uniform description of a calculus, called tractor calculus, based on natural bundles with canonical linear connections for all parabolic geometries. It is sh...