Investigation of metal flow in bridge die extrusion of Alloy 6063 and subsequent effect on surface quality and weld seam integrity

This paper describes a detailed study of tube extrusion by simulation using finite element method (FEM). The finite element model used one-sixth of symmetry. The extrusion load, emperature evolution and metal flow were predicted. Innovative methods, combining both grid and surface tools, were used to define in detail the flow of material. These showed clearly the inner and outer surface formation mechanisms of the tube extrusion. The seam weld, an important quality indicator, was also evaluated by selecting an appropriate criterion

Proceedings of a seminar on Future Directions for New Zealand Lamb Marketing

A seminar on lamb marketing was organised to provide a forum for discussion of this important issue, as New Zealand faces significant changes in the lamb marketing environment. The increasing importance of new lamb markets, especially in the Middle East, the importance of the North American market and the increasing fragility of the United Kingdom lamb market, make such discussion very timely. In addition, the market requirement for lambs with a lower fat content has meant that lamb grading standards have been more rigorously set and substantial price schedule penalties have been imposed for over fatness. Increasing production, processing and transportation costs have meant that the farmers share, of the market price for lamb, has fallen. This means that it has become even more important to achieve the maximum possible market return. The achievement of this target must depend on the markets available, the type of marketing activity undertaken in those markets and the structure of the industry supporting the marketing effort. The optimum results may not be available based on the present industry structure and approach and it was therefore considered appropriate that alternatives be reviewed and examined with a view to the future. Includes full text of the papers: Hilgendorf, C. New Zealand lamb marketing: the past and present; Cullwick, T.D.C. The need for a global marketing strategy for lamb and lamb products

S-band omnidirectional antenna for the SERT-C satellite

The program to design an S-band omnidirectional antenna system for the SERT-C spacecraft is discussed. The program involved the tasks of antenna analyses by computer techniques, scale model radiation pattern measurements of a number of antenna systems, full-scale RF measurements, and the recommended design, including detailed drawings. A number of antenna elements were considered: the cavity-backed spiral, quadrifilar helix, and crossed-dipoles were chosen for in-depth studies. The final design consisted of a two-element array of cavity-backed spirals mounted on opposite sides of spacecraft and fed in-phase through a hybrid junction. This antenna system meets the coverage requirement of having a gain of at least minus 10 dBi over 50 percent of a 4 pi steradian sphere with the solar panels in operation. This coverage level is increased if the ground station has the capability to change polarization

Relationships between lower-body muscle structure and, lower-body strength, explosiveness and eccentric leg stiffness in adolescent athletes

The purpose of the present study was to determine whether any relationships were present between lower-body muscle structure and, lower-body strength, variables measured during a counter-movement jump (CMJ) and squat jump (SJ), and eccentric leg stiffness, in adolescent athletes. Thirty junior male (n = 23) and female (n = 7) surfing athletes (14.8 ± 1.7 y; 1.63 ± 0.09 m; 54.8 ± 12.1 kg) undertook lower-body muscle structure assessment with ultrasonography and performed a; CMJ, SJ and an isomet-ric mid-thigh pull (IMTP). In addition, eccentric leg stiffness was calculated from variables of the CMJ and IMTP. Moderate to very large relationships (r = 0.46-0.73) were identified be-tween the thickness of the vastus lateralis (VL) and lateral gas-trocnemius (LG) muscles, and VL pennation angle and; peak force (PF) in the CMJ, SJ and IMTP. Additionally, moderate to large relationships (r = 0.37-0.59) were found between eccentric leg stiffness and; VL and LG thickness, VL pennation angle, and LG fascicle length, with a large relationship (r = 0.59) also present with IMTP PF. These results suggest that greater thick-ness of the VL and LG were related to improved maximal dy-namic and isometric strength, likely due to increased hypertro-phy of the extensor muscles. Furthermore, this increased thickness was related to greater eccentric leg stiffness, as the associated enhanced lower-body strength likely allowed for greater neuromuscular activation, and hence less compliance, during a stretch-shortening cycle

Variation of turbulent burning rate of methane, methanol, and iso-octane air mixtures with equivalence ratio at elevated pressure

Turbulent burning velocities for premixed methane, methanol, and iso-octane/air mixtures have been experimentally determined for an rms turbulent velocity of 2 m/s and pressure of 0.5 MPa for a wide range of equivalence ratios. Turbulent burning velocity data were derived using high-speed schlieren photography and transient pressure recording; measurements were processed to yield a turbulent mass rate burning velocity, utr. The consistency between the values derived using the two techniques, for all fuels for both fuel-lean and fuel-rich mixtures, was good. Laminar burning measurements were made at the same pressure, temperature, and equivalence ratios as the turbulent cases and laminar burning velocities and Markstein numbers were determined. The equivalence ratio (φ) for peak turbulent burning velocity proved not always coincident with that for laminar burning velocity for the same fuel; for isooctane, the turbulent burning velocity unexpectedly remained high over the range φ = 1 to 2. The ratio of turbulent to laminar burning velocity proved remarkably high for very rich iso-octane/air and lean methane/air mixtures

Towards understanding the availability of physiotherapy services in rural Australia

Introduction: A recent exploration of factors affecting rural physiotherapy service provision revealed considerable variation in services available between communities of the study. Multiple factors combined to influence local service provision, including macro level policy and funding decisions, service priorities and fiscal constraints of regional health services and capacity and capabilities at the physiotherapy service level. The aim of this article is to describe the variation in local service provision, the factors influencing service provision and the impact on availability of physiotherapy services. Methods: A priority-sequence mixed methods design structured the collection and integration of qualitative and quantitative data. The investigation area, a large part of one Australian state, was selected for the number of physiotherapy services and feasibility of conducting site visits. Stratified purposive sampling permitted exploration of rural physiotherapy with subgroups of interest, including physiotherapists, their colleagues, managers, and other key decision makers. Participant recruitment commenced with public sector physiotherapists and progressed to include private practitioners, team colleagues and managers. Surveys were mailed to key physiotherapy contacts in each public sector service in the area for distribution to physiotherapists, their colleagues and managers within their facility. Private physiotherapist principals working in the same communities were invited by the researcher to complete the physiotherapy survey. The survey collected demographic data, rural experience, work setting and number of colleagues, services provided, perspectives on factors influencing service provision and decisions about service provision. Semi-structured interviews were conducted with consenting physiotherapists and other key decision makers identified by local physiotherapists. Quantitative survey data were recorded in spreadsheets and analysed using descriptive statistics. Interviews were recorded and transcribed verbatim, with transcripts provided to participants for review. Open-ended survey questions and interview transcripts were analysed thematically. Results: Surveys were received from 11/25 (44%) of facilities in the investigation area, with a response rate of 29.4% (16/54) from public sector physiotherapists. A further 18 surveys were received: five from principals of private physiotherapy practices and 13 from colleagues and managers. Nineteen interviews were conducted: with 14 physiotherapists (nine public, five private), four other decision makers and one colleague. Three decision makers declined an interview. The variation in physiotherapy service availability between the 11 communities of this study prompted the researchers to consider how such variation could be reflected. The influential factors that emerged from participant comments included rurality and population, size and funding model of public hospitals, the number of public sector physiotherapists and private practices, and the availability of specialised paediatric and rehabilitation services. The factors described by participants were used to develop a conceptual framework or index of rural physiotherapy availability. Conclusions: It is important to make explicit the link between workforce maldistribution, the resultant rural workforce shortages and the implications for local service availability. This study sought to do so by investigating physiotherapy service provision within the rural communities of the investigation area. In doing so, varying levels of availability emerged within local communities. A conceptual framework combining key influencing factors is offered as a way to reflect the availability of physiotherapy services

Towards understanding the availability of physiotherapy services in rural Australia

Introduction: A recent exploration of factors affecting rural physiotherapy service provision revealed considerable variation in services available between communities of the study. Multiple factors combined to influence local service provision, including macro level policy and funding decisions, service priorities and fiscal constraints of regional health services and capacity and capabilities at the physiotherapy service level. The aim of this article is to describe the variation in local service provision, the factors influencing service provision and the impact on availability of physiotherapy services. Methods: A priority-sequence mixed methods design structured the collection and integration of qualitative and quantitative data. The investigation area, a large part of one Australian state, was selected for the number of physiotherapy services and feasibility of conducting site visits. Stratified purposive sampling permitted exploration of rural physiotherapy with subgroups of interest, including physiotherapists, their colleagues, managers, and other key decision makers. Participant recruitment commenced with public sector physiotherapists and progressed to include private practitioners, team colleagues and managers. Surveys were mailed to key physiotherapy contacts in each public sector service in the area for distribution to physiotherapists, their colleagues and managers within their facility. Private physiotherapist principals working in the same communities were invited by the researcher to complete the physiotherapy survey. The survey collected demographic data, rural experience, work setting and number of colleagues, services provided, perspectives on factors influencing service provision and decisions about service provision. Semi-structured interviews were conducted with consenting physiotherapists and other key decision makers identified by local physiotherapists. Quantitative survey data were recorded in spreadsheets and analysed using descriptive statistics. Interviews were recorded and transcribed verbatim, with transcripts provided to participants for review. Open-ended survey questions and interview transcripts were analysed thematically. Results: Surveys were received from 11/25 (44%) of facilities in the investigation area, with a response rate of 29.4% (16/54) from public sector physiotherapists. A further 18 surveys were received: five from principals of private physiotherapy practices and 13 from colleagues and managers. Nineteen interviews were conducted: with 14 physiotherapists (nine public, five private), four other decision makers and one colleague. Three decision makers declined an interview. The variation in physiotherapy service availability between the 11 communities of this study prompted the researchers to consider how such variation could be reflected. The influential factors that emerged from participant comments included rurality and population, size and funding model of public hospitals, the number of public sector physiotherapists and private practices, and the availability of specialised paediatric and rehabilitation services. The factors described by participants were used to develop a conceptual framework or index of rural physiotherapy availability. Conclusions: It is important to make explicit the link between workforce maldistribution, the resultant rural workforce shortages and the implications for local service availability. This study sought to do so by investigating physiotherapy service provision within the rural communities of the investigation area. In doing so, varying levels of availability emerged within local communities. A conceptual framework combining key influencing factors is offered as a way to reflect the availability of physiotherapy services

Seasonality in the New Zealand meat processing industry

The research reported in this publication is a part of the Agricultural Economics Research Unit's continuing research effort into marketing and processing charges for livestock. Research Report No.103 ("A Study of Excess Livestock Transport Costs in the South Island of New Zealand" by R.D. Inness and A.C. Zwart) presented the results of an analysis of the cartage pattern of livestock to freezing works for the 1977/78 season. This study identified a transport penalty cost of about $0.5 million associated with seasonality of sheep and lamb supply in the South Island. The present study attempts to provide an economic assessment of the seasonality associated with the operation of the New Zealand meat processing industry and the relationship between seasonality and overcapacity. The author reviews the fixed/variable nature of costs in the freezing industry and suggests that the future path for the industry is likely to be the replacement of high labour fixed costs by lower capital fixed costs via the establishment of smaller higher technology works. This would allow more effective and efficient operation during the off-peak period of slaughter and may allow the payment of premiums to encourage off-peak production