SINGLE SPECIES VERSUS MULTIPLE SPECIES MODELS: THE ECONOMIC IMPLICATIONS

Ecologists frequently note the importance of modelling entire ecosystems rather than single species, but most bioeconomic models in the current literature focus on a single species. While the mathematical difficulty of multiple species may quickly become overwhelming, sometimes making the single species option necessary, it is important to recognise the significance of the single species assumption to the model results. In this paper, the authors address the economic significance of this assumption through the development of a multiple species model and demonstrate the importance of interrelationships and economic values to the survival of endangered species.Resource /Energy Economics and Policy,

Animal Efficiency in an Intensive Beef Production System

A stochastic input distance function is estimated to analyse the efficiency with which physical characteristics of individual lot-fed beef cattle in Australia are combined with conventional inputs to produce a final product possessing defined quality attributes. High mean technical efficiency estimates are reported for all animals and by breed. All partial output elasticities with respect to inputs are of expected sign. Of four outputs included in the analysis, carcass weight and moisture retention in meat after cooking have highly significant coefficients of expected sign, but two meat quality variables have coefficients of unexpected sign indicating that they decline as inputs increase. Some evidence is detected of scope economies between moisture retention in meat and the inverse of meat compression.efficiency, intensive agriculture, scope economies, Livestock Production/Industries, Q12, C51,

Use of computer-aided analysis techniques for cover type mapping in areas of mountainous terrain

There are no author-identified significant results in this report

An improved perturbation approach to the 2D Edwards polymer -- corrections to scaling

We present the results of a new perturbation calculation in polymer statistics which starts from a ground state that already correctly predicts the long chain length behaviour of the mean square end--to--end distance $\langle R_N^2 \rangle\$, namely the solution to the 2~dimensional~(2D) Edwards model. The $\langle R_N^2 \rangle$ thus calculated is shown to be convergent in $N$, the number of steps in the chain, in contrast to previous methods which start from the free random walk solution. This allows us to calculate a new value for the leading correction--to--scaling exponent~$\Delta$. Writing $\langle R_N^2 \rangle = AN^{2\nu}(1+BN^{-\Delta} + CN^{-1}+...)$, where $\nu = 3/4$ in 2D, our result shows that $\Delta = 1/2$. This value is also supported by an analysis of 2D self--avoiding walks on the {\em continuum}.Comment: 17 Pages of Revtex. No figures. Submitted to J. Phys.

Designing an effective evaluation model for the South African Department of Agriculture

Governments are under increasing pressure to deliver results. Therefore, it is important to evaluate the effectiveness, efficiency and relevance of the public service in implementing policies and programmes for social betterment. Without such evaluations, it is difficult to ensure that evidence is integrated into policy and used in practice due to lack of generalizability and learning. This paper focuses on (1) the knowledge that is relevant to understand evaluation influence, (2) the possible conceptual frameworks that enable understanding of the evaluation implementation process, (3) possible models of the process of organizational evaluation, and (4) the main ways of intervening to increase influence. The context for analysis is the South African Department of Agriculture.Evaluation, Evaluation Influence, Policy, Programmes, South Africa, Political Economy, Research Methods/ Statistical Methods,

Magnetic control assembly qualification model

Fabrication and testing of the magnetic control assembly (MCA) are summarized. The MCA was designed as an add-on unit for certain existing components of the Nimbus and ERTS attitude control system. The MCA system consists of three orthogonal electromagnets; a magnetometer probe capable of sensing external fields in the X, Y, and Z axes; and the control electronics. An operational description of the system is given along with all major drawings and photographs. Manufacturing and inspection procedures are outlined and a chronological list of events is included with the fabrication summary

Meta-evaluations in government and government institutions: A case study example from the Australian Centre for International Agricultural Research

In this paper we draw on impact assessment work of the Australian Centre for International Agricultural Research (ACIAR) to present an example of meta-evaluation – an evaluation of evaluations – in an agricultural research, development and extension setting. We explore quality issues relating to evaluation studies in the context of government institutions. Program evaluation standards (PES) are divided into categories of utility, feasibility, propriety and accuracy to provide a framework for the meta-evaluation. The PES are presented as a universal measure of evaluation study quality. The intent of using them here is to judge the adequacy of PES as a universal quality measure or meta-evaluation base and to extract useful insights from ACIAR program evaluation activities when developing a meta-evaluation model for the Limpopo Department of Agriculture (LDA). Our meta-evaluation is undertaken of 63 impact assessment reports. First, the literature guiding the conduct of a meta-evaluation is reviewed. Second, an assessment (the meta-evaluation) of the evaluation studies is carried out for 19 sampled reports from a population of relevant reports fitting the dimension of the analysis, and results are presented and discussed. Also, lessons learned are presented, using the framework provided by the meta-evaluation criteria. Third, taking into account the lessons learned, implications are drawn for a proposed systematic meta-evaluation of the LDA. Finally, we conclude that all the PES cannot be equally emphasized in a meta-evaluation model. At ACIAR, 70% of the standards were at least partially addressed. Therefore, we succeeded in using the PES in judging the ACIAR evaluation quality. As such, they can be an important base when developing an evaluation model but should be applied in a contextualized manner.Meta-evaluation, Evaluation Quality, Program Evaluation Standards, Evaluation Model, Australian Centre for International Agricultural Research, Limpopo Department of Agriculture (South Africa), International Development,

Market Differentials for Meat Quality Improvement: Meat Standards Australia

Eating quality is one of the most important factors influencing demand for beef. Meat Standards Australia is a voluntary beef grading system aimed at improving consumer certainty about beef quality, improving overall beef quality and strengthening supply chain linkages. Since its inception in 1999/2000, substantial improvements in beef quality, as measured by the system, have been identified. An evaluation was undertaken to estimate the economic value of these improvements to the industry. It was found that MSA graded beef consistently attracted premiums above nongraded beef, with mean values of 29c/kg and 39c/kg (carcass equivalent) at the wholesale and retail levels respectively, while the food service sector received an average of 39c/kg (carcass equivalent). The total retail value of the program to date is estimated to be between $218 to 230 million and$171 million at the wholesale level (in terms of 2005 prices).Livestock Production/Industries,

High Pressure Effects on Superconductivity in the beta-pyrochlore Oxides AOs2O6 (A=K, Rb, Cs)

Recently new pyrochlore oxides superconductors AOs2O6 (A=K,Rb,Cs) were found and we measured the pressure dependence of magnetization up to 1.2 GPa in order to deduce the pressure effect of Tc in the three beta-pyrochlore oxides. It is found that the initial pressure dependence of Tc is positive for all the compounds. Only KOs2O6 exhibits a saturation in Tc at 0.56 GPa and the downturn at higher pressureComment: 7 pages, 2 figure

The solar dynamic radiator with a historical perspective

A historical perspective on pumped-fluid loop space radiators provides a basis for the design of the Space Station Solar Dynamic (SD) power module radiator. SD power modules, capable of generating 25 kW (electrical) each, are planned for growth in Station power requirements. The Brayton cycle SD module configuration incorporates a pumped-fluid loop radiator that must reject up to 99 kW (thermal). The thermal/hydraulic design conditions in combination with required radiator orientation and packaging envelope form a unique set of constraints as compared to previous pumped-fluid loop radiator systems. Nevertheless, past program successes have demonstrated a technology base that can be applied to the SD radiator development program to ensure a low risk, low cost system