in this study an innovatively designed tractor-mounted, ground-wheel driven, triple unit, row crop precision planter capable of planting three rows of garlic (allium sativum l.) cloves on each raised bed was designed, fabricated and tested. the major components of this planter include; chassis and transport wheels, lister-bedder unit, seed hopper, seed metering drum, sweeper, knocker, seed tube...

Historically preparing cottonseed for planting purposes involved the use of an acid delinting process, which allows the seed to flow in a single seed manner required for planting. This process is very effective and inexpensive, yet it could potentially be very hazardous to the seed, workers and the environment. This study evaluates the performance of a polymer starch coating applied to partiall...

for planting fine seeds in cellular trays, an automatic pneumatic seeder was designed, constructed and evaluated. catia software was used to design and analysis the system parts of the seeder. different parts of the seeder, including vibrating seed hopper, vacuum boom, seed picking nozzles, seed tube, pneumatic system and electronic control unit for automation of the seeder, were designed and c...

The goal of this research project was oriented around the hypothesis that drifting talc powder from seed hoppers planting in a field causes honey bee mortality. It is known that seed treatment manufacturers are required to examine the toxicity of the individual components but are not required to examine the toxicity of the cocktail that makes up the entire seed treatment. We hypothesized that t...

MIT is developing an Earth-based hopper prototype for autonomous planetary exploration. This paper describes the initial development of the hopper prototype and its application as a testbed for lunar hopper technologies. The prototype hopper consists of a gravity-canceling system, composed of battery-powered electric ducted fans, and an integrated lunar hopper system, which operates using cold ...

The Murφ-based Hopper tool is a general purpose explicit model checker. Hopper leverages Murφ’s class structure to implement new algorithms. Hopper differs from Murφ in that it includes in its distribution published parallel and disk based algorithms, as well as several new algorithms. For example, Hopper includes parallel dynamic partitioning, cooperative parallel search for LTL violations and...

This study investigated generalization decrement during an extinction resistance-to-change test for pigeon key pecking using a two-component multiple schedule with equal variable-interval 3-min schedules and different reinforcer amounts (one component presented 2-s access to reinforcement and the other 8s). After establishing baseline responding, subjects were assigned to one of the two extinct...

The discharge of granular material from a hopper subject to vertical sinusoidal oscillations was investigated using experiments and discrete element computer simulations. With the hopper exit closed, side-wall convection cells are observed, oriented such that particles move up along the inclined walls of the hopper and down at the center line. The convection cells are a result of the granular b...

Jenike’s radial solution, widely used in the design of materials-handling equipment, is a similarity solution of steady-state continuum equations for the flow under gravity of granular material through an infinite, right-circular cone. In this paper we study how the geometry of the hopper influences this solution. Using perturbation theory, we compute a first-order correction to the (steady-sta...

In this paper, we study the global dynamics of a simple passive mechanical model for hopping. The hopper is a two-mass, single-spring system constrained to move in the vertical direction (under gravity) above a rigid ground. The hopper model and its basic dynamics including the existence of incessant hopping motions have been reported elsewhere. Here, we extend the study to investigate the glob...