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.

Plant protection unmanned aircraft vehicles (UAVs) were developed rapidly in China. The operation performances of different models UAVs different. This paper systematically studied droplet deposition distribution; pesticide-mixture utilization rate; operational efficiency; wheat-disease control efficacy; and a comprehensive score three types UAVs, boom sprayer, knapsack sprayer. results showed ...

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...

The objective of this study was to improve the spraying efficiency and meet the demand of modern agricultural. A new generation of electrostatic sprayer which we designed realized the goals. The automatic controlling system is successfully designed. PLC (Programmable Logic Controller) was taken as the control core of the system and LCD touch screen was employed for human-computer interaction in...

Aero-Pipeline Spraying System is a special ultra-working-width precision pesticide sprayer, which can broaden working scope, improve working efficiency, precisely transfer feed liquid to farm field that need to be sprayed, spray pesticides to crops in a very close range, and then improve working precision and reduce the losses of liquid materials such as pesticides. During the ultra-working-wid...

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...

Table 1. Effect of paclobutrazol (paclo) on plant height and number of leaves developed on hollyhock at 2, 4, or 6 weeks after treatment. All application techniques were designed to deliver 0.10 mg paclo/10-cm Our objective was to determine the efficacy of a given dosage of β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H1,2,4-triazole-1-ethanol [paclobutrazol (paclo)] applied using differin...

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...