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This paper is concerned with the theoretical and practical engineering development issues, necessary for the design, build and test of an afterburner thrust augmentation system for a model aircraft gas turbine engine.

Research into key combustion parameters including, flame holder diameter, flame holder edge velocity, burner velocity and equivalence ratio were undertaken. This information was used as the basis for the design and fabrication of the afterburner combustion system. The after burner system had been designed to fit a Wren MW54 model gas turbine engine, that included FADEC control for the mother engine. Substantial testing of the afterburner system was undertaken.

Changes in “dry” and “wet” jet efflux temperature while the engine is accelerating from idle to full power are found. The increase in temperature between the dry and wet case are not markedly different, demonstrating the poor quality of the afterburner flame: the testing of the afterburner system resulted in limited flame substantiation being achieved.

Further research is required and is currently being undertaken, into the computational modelling of fuel atomisation issues and further engineering of the fuel injection system.

This afterburner design may eventually be adopted by Wren Turbines for economic production.

Provides further information on the engineering and efficiency problems associated with very small‐scale gas turbine engines.

The complexities of environmental issues require that when developing new green products marketers have to seek‐out, involve and learn from stakeholders with environmental expertise. These stakeholders have information that lies outside the organisation’s main area of expertise and can assist the firm in developing less environmentally harmful products. This article examines US and Australian markets’ perceptions of stake‐holders’ potential to influence the green new product development (NPD) process and what strategies can be used to involve stakeholders in this process. The findings suggest that marketers believe some stakeholders with “high” influencing abilities should be involved in the green NPD process, although it appears that in practice, firms use very basic methods to include these stakeholders. It also appears that there is limited formal interaction between the firm and its stakeholders and that respondents are not engaging and learning from others with green product expertise.

PRODUCTIVITY is a constant awareness of the need to make more efficient use of the production resources, and the efficiency/performance returns in each factory will testify to the thoroughness of work study. There will be those factories where work study is discredited in that production methods have remained static, original study work has not been properly recorded and amendments have gone by the board with the inevitable consequence that standards slip. Any work study findings are no longer accepted as valid with the result that work measurement degenerates to the level of rate fixing.

IT is reported that trade union officials of the more progressive type are now recognising the implacable advance of work study and that, in many trades, officials are being trained as work study technicians. The report goes on to say, however, that management is reluctant to accept union representatives “in this light”.

The paper describes the development of a specialised bilingual online database providing hyperlinks to Internet and other resources for researchers. The project grew from the need to provide current information for a new business area coinciding with the wish of the library staff to demonstrate leadership in knowledge management, making information accessible, no matter what its format or geographic location. Steps in planning the project are laid out. International standards for cataloguing electronic resources were not finalised, so the team adopted the best available for their purpose, building in enough flexibility to allow future adaptation. Our experience demonstrates the urgent need for finalised standards and led us to conclude that although consensus building is often desirable, sometimes there is a need to move forward more quickly with defined standards to prevent development stalling or extensive rework being required. Database elements, based on the Dublin Core metadata structure, are detailed.

Background to the European Commission consultation on the electronic money directive (2000/46/EC) with particular reference to the definition of ‘electronic money’, the impact on mobile telephone operators, different structures for payment of goods and services under schemes for the issue of prepaid electronic value, the regulatory requirements on banks and e‐money institutions and the application of anti‐money laundering requirements.

Erosion and abrasion are the prominent wear mechanisms reducing the lifetime of machine components. Both wear mechanisms are playing a role meanwhile, generating a synergy, leading to a material removal on the target. The purpose of study is to create a mathematical expression for erosive abrasive wear.

Many factors such as environmental cases and material character have an influence in erosive abrasive wear. In the work, changes in abrasive size and material hardness have been analyzed. As an abrasive particle, quartz sand has been used. All tests have been done in 20 wt.% slurry. Heat treatment has been applied to different steel specimens (steel grades C15, St 37 and Ck45) to change hardness value, which ranged from 185 to 880 Vickers hardness number.

After the four-hour test, it is determined that by an increase in abrasive size and decrease in material hardness, wear rate increases. Worn surfaces of the targets have been examined to figure out the wear mechanisms at different conditions under scanning electron microscopy. The results indicate that by an increase in material hardness, the number and diameter of micro-craters on the worn surfaces decrease. The diameters of micro-craters have been about 3–8 µm in hard materials and about 120–140 µm in soft materials.

It is determined that by an increase in abrasive size and decrease in material hardness, wear rate increases. The results indicate that by an increase in material hardness, the number and diameter of micro-craters on the worn surfaces decrease.

The study enables to indicate the dominant factor in worn steel used in mechanical components.

After analyzing the test results, a novel mathematical expression, considering both abrasive size and material hardness, has been developed.