Showing papers in "Journal of Agricultural Engineering Research in 1980"

TL;DR: In this article, the effect of varying tyre diameter and width on a lightly loaded and a heavily loaded axle in different field conditions was investigated and the maximum possible tractive efficiency was calculated.

TL;DR: In this article, a greatly simplified version of the critical state theory of soil mechanics is presented to cope with soil moisture changes in agricultural practice and some simple field examples are analysed and a generalized extension of the theory is presented.

TL;DR: In this article, the performance of a wide range of cultivation machinery for reduced cultivation and direct drilling was compared with traditional cultivations in co-operative cereal experiments on three soils between 1971 and 1977.

TL;DR: In this article, the authors presented estimates of the energy sequestered in the production of tomatoes by 6 different cropping systems, 5 of them practised with varying degrees of environmental protection in Mediterranean climatic regions, and one in heated glasshouses in a more northern region.

TL;DR: In this article, the coefficients of friction of seven materials which could be used in the construction of agricultural silo walls (or as linings) were determined for wheat and barley at different moisture contents within a range of 10 to 20% (w.b.).

TL;DR: In this paper, a full scale experimental section of a pig finishing building was used to determine the distributions of cooling effect (air speed and air temperature combined) for a number of penning layouts and traditional straight-through ventilation systems.

TL;DR: In this article, the development and testing of a cyclone type husk fired furnace which can be used either for heating the drying air or for generating steam in a boiler for parboiling of paddy in the rice mill is described.

TL;DR: A greater reduction in potato damage could be achieved by redesign of a harvester riddling system to provide a horizontal instead of a vertical shaking motion, than by growing damage resistant varieties.

TL;DR: In this paper, a wooden frame supporting a metal track in which a wheeled trolley with a vertically mounted spray nozzle is rapidly pulled back and forth along the plot is used to simulate rainfall, providing a water supply, and collecting sediment from a bounded plot.

TL;DR: In this paper, an array of 3 small wing-like extensions, called sails, fitted horizontally to each of the wing tips of a Piper Pawnee aricraft was shown to reduce the amount of spray carried off-target by crosswinds.

TL;DR: In this article, the authors make proposals for the design of terraces to retain water and a method is given for calculating the depth of storage required, where terraces should be raised periodically to maintain adequate storage capacity which would otherwise be reduced by sedimentation.

TL;DR: In this article, two new designs of shear box were investigated and the first was discarded because of the uncertainty of the true value of the normal stress, while the second design was used to determine the effect of variations in experimental technique on the results obtained.

TL;DR: In this article, the authors used an equilibrium drying model to predict the possible savings in electrical energy that could result from adding a solar collector to an ambient-air in-bin drier for wheat and corn in the main grain-growing regions of Canada.

TL;DR: In this article, a new cracker for macadamia nuts was developed and tested, which utilizes the principle of a constant deformation rate, which ensures a uniform, continuous cracking and results in a better recovery of the kernels.

TL;DR: In this paper, a simple, versatile, adjustable width soil bin suitable for studying and testing both full scale and model agricultural implements is presented, along with operational characteristics and design details and operational characteristics.

TL;DR: In this paper, the authors evaluated the accuracy and sensitivity of the sensor and concluded that it was robust, reliable, and did not drift in calibration during 3 years of use, and also showed that the sensor was robust to small changes in moisture content.

TL;DR: In this paper, the rear view mirror must be at least 20 cm × 30 cm and for many operations convex glass is most suitable, and the mirrors must be properly located and fixed to the tractor.

TL;DR: In this paper, ammonium propionate has important advantages over propionic acid, and that coarse drop application at appropriate rates, when combined with the final windrowing, is an effective method of hay treatment.

TL;DR: The van Schilfgaarde transient watertable model is shown to be applicable to the drainage of heavy clay soils in the English context in this article, where the model is calibrated against a site in Leicestershire, and then subjected to 10 years' climatic record representative of contrasting areas in Bedfordshire and Devon.

TL;DR: In this article, the authors measured diffuse reflectance spectra for different grass species at near infrared wavelengths from 1100 nm to 2100 nm and found that different responses to leaf and stem may explain much of the observed scatter.

TL;DR: In this paper, an approximate method is presented for the rapid evaluation of the passive soil thrust on such surfaces using non-dimensional earth resistance coefficients, obtained from statically admissible rupture surface configurations developed by combining Sokolovski type slip-line fields with a specially modified Rankine plane shear zone.

TL;DR: In this article, a 104 m2 inflated plastic air heater with black plastic suspended screens as extra absorbing surfaces was tested and compared against an air heater without the screens, showing that the increase in efficiency more than offsets the cost of the screens.

TL;DR: In this paper, the emissivity and transmittance of the screen and the ventilation through screen and glass was investigated. But the authors only considered the lower side of the glass screen and did not consider the upper side of screen.

TL;DR: In this paper, the authors presented the results from five buildings subjected to transverse winds as pressure coefficients which relate wind loads to the free stream dynamic wind pressure at the ridge height of a building and may therefore be used in the design procedures of British Standard Code of Practice CP3.

TL;DR: In this paper, a capillary viscometer capable of measuring the flow properties of slurries with solids concentrations up to 33% is described, which can be used to measure pressure losses caused by bends and fittings.

TL;DR: In this paper, the effect of speed on wear in soils is discussed with reference to the effective load and sliding distance for wear, and the actual cost of wear per unit area tilled and the relative cost of using materials with high wear resistance may increase as speeds increase.

TL;DR: In this paper, the authors derived an equation relating errors in seed release from seed delivery mechanisms to seed spacing distributions in the furrow, and derived a model which predicts the optimum release point for a cell wheel mechanism.

TL;DR: In this article, a new cell was developed which showed a better separation effectiveness in the case of beans, when compared with the conventional cell, and a systematic study was conducted to establish the optimum parameters of the cell design.

TL;DR: In this article, a new model is proposed which relates shear and normal strain increments to shear, and normal stress increments, including cross-coupling between shears and normal quantities.