3,137 research outputs found

    Factors affecting the establishment of Leptospermum scoparium J.R. et G. Forst. (manuka) : a thesis presented in partial fulfillment of the requirements for the degree of Master of Agricultural Science at Massey University

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    L. scoparium is one of New Zealand's most important weeds of unploughable infertile hill country. The plant is an indigenous shrub, characteristic of the early stages of succession to forest in a wide range of habitats (Cockayne, 1928). In the eight years prior to 1959/60 nearly 40,000 acres of unimproved grassland reverted to scrub, fern and second growth each year. L. scoparium is one of the most important components of the scrub, fern and second growth category. By 1959/60 the total area of reverted land in New Zealand was 5.7 million acres of which 3.65 million were in the North Island. (Rigg, 1962). Control of L. scoparium on unploughable hill country has been limited to pulling, cutting, or cutting and burning, depending on stage of growth. Chemical methods and standing burns have generally proved unsuccessful. Most methods are expensive. Levy (1932, 1940, 1946) postulated that establishment of L. scoparium in pasture could be prevented by good farming techniques. Today there is a growing body of practical evidence to support this hypothesis (Suckling, 1959; New Zealand Farmer 83 (42, 43, 45)). This study was carried out to determine what intrinsic factors favour the establishment of L. scoparium, and the quantitative effect of farm management techniques on this process

    Wind-driven mixing below the oceanic mixed layer

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    This study describes the turbulent processes in the upper ocean boundary layer forced by a constant surface stress in the absence of the Coriolis force using large-eddy simulation. The boundary layer that develops has a two-layer structure, a well-mixed layer above a stratified shear layer. The depth of the mixed layer is approximately constant, whereas the depth of the shear layer increases with time. The turbulent momentum flux varies approximately linearly from the surface to the base of the shear layer. There is a maximum in the production of turbulence through shear at the base of the mixed layer. The magnitude of the shear production increases with time. The increase is mainly a result of the increase in the turbulent momentum flux at the base of the mixed layer due to the increase in the depth of the boundary layer. The length scale for the shear turbulence is the boundary layer depth. A simple scaling is proposed for the magnitude of the shear production that depends on the surface forcing and the average mixed layer current. The scaling can be interpreted in terms of the divergence of a mean kinetic energy flux. A simple bulk model of the boundary layer is developed to obtain equations describing the variation of the mixed layer and boundary layer depths with time. The model shows that the rate at which the boundary layer deepens does not depend on the stratification of the thermocline. The bulk model shows that the variation in the mixed layer depth is small as long as the surface buoyancy flux is small

    DOES PRIVATE LABEL OWNERSHIP AND PRICING STRUCTURE MATTER?

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    This article provides an analysis of the two-stage game between manufacturers and retailers. Response functions showing how prices are set are derived for the case of a manufacturer producing one and multiple goods and for a retailer selling multiple goods. The functions are expressed in terms of elasticities, budget shares, and variable production costs. An application using ready-to-eat cereals is conducted to investigate the pricing structure and ownership of private label cereals.Demand and Price Analysis,

    Characteristics of Langmuir Turbulence in the Ocean Mixed Layer

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    This study uses large-eddy simulation (LES) to investigate the characteristics of Langmuir turbulence through the turbulent kinetic energy (TKE) budget. Based on an analysis of the TKE budget a velocity scale for Langmuir turbulence is proposed. The velocity scale depends on both the friction velocity and the surface Stokes drift associated with the wave field. The scaling leads to unique profiles of nondimensional dissipation rate and velocity component variances when the Stokes drift of the wave field is sufficiently large compared to the surface friction velocity. The existence of such a scaling shows that Langmuir turbulence can be considered as a turbulence regime in its own right, rather than a modification of shear-driven turbulence. Comparisons are made between the LES results and observations, but the lack of information concerning the wave field means these are mainly restricted to comparing profile shapes. The shapes of the LES profiles are consistent with observed profiles. The dissipation length scale for Langmuir turbulence is found to be similar to the dissipation length scale in the shear-driven boundary layer. Beyond this it is not possible to test the proposed scaling directly using available data. Entrainment at the base of the mixed layer is shown to be significantly enhanced over that due to normal shear turbulence

    Purification of Tannery Effluent by electrolytic corrosion of aluminium

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    Tannery Effluent is noxious because tanning process chemicals are preservatives, including chromium, and the pH is high. Electrolytic processing is feasible because the high salt content gives a high electrical conductivity. While research on the subject dates back to early in the 20th Century, commercialization has not occurred, perhaps due to excessive power consumption. Other researchers have produced promising results with rendering plant effluent (Tetrault 2003). During 2005 a specialised proprietary prototype with a novel anode design was trialed extensively at a Tannery site in New Zealand and produced good results during continuous inline operation despite wide variation in the inflow. Greater than 90% removal of chromium from solution with similar reductions in turbidity were achieved at lower operating cost, residual aluminum and total aluminum addition than by dosing with usual commercial aluminum based flocculants. Results from the field trials are shown and discussed

    Book Review: Sentencing, by Clayton C. Ruby

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