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ON aircraft operating in the rarefied atmosphere at high altitude, the idea of supplementing the air consumed by the engine with extra oxygen would seem to be a logical and desirable development, because the power output of a reciprocating engine is a direct function of the oxygen content of the air charge, provided that all the oxygen is burnt in the cylinder. However, the normal and most satisfactory line of development has been to fit the aircraft with engines of increased capacity or supercharge, so that the oxygen content of the air charge is increased simply by increasing the total mass of air consumed by the engine.

Vortex grippers use tangential nozzles to form vortex flow and are able to grip a workpiece without any physical contact, thus avoiding any unintentional workpiece damage. This study aims to use experimental and theoretical methods to investigate the effects of nozzle diameter on the performance.

First, various suction force-distance curves were developed to analyze the effects of nozzle diameter on the maximum suction force. This study determines the tangential velocity distribution on the workpiece surface by substituting the experimental pressure distribution data into simplified Navier-Stokes equations and then used these equations to analyze the effects on the flow field. Subsequent theoretical analysis of the distribution of pressure and circumferential velocity further validated the experimental results. Next, by rearranging these relationships, the study considered the effects of nozzle diameter on the inherent vortex gripper characteristics. In addition, this study developed various suction force-energy consumption curves to analyze the effects of nozzle diameter.

The results of this study indicated that the vortex gripper’s circumferential velocity and maximum suction force decrease with increasing nozzle diameter. Nozzle diameter did not significantly affect the inherent frequency of the vortex gripper-workpiece inertial system or the corresponding suspension stability of the workpiece. However, an increase in nozzle diameter did effectively increase the vortex gripper’s suspension region. Finally, as the nozzle diameter increased, the energy required to achieve the same maximum suction force decreased.

This study’s findings can enable optimization of nozzle design in emerging vortex gripper designs and facilitate informed selection among existing vortex grippers.

The purpose of this study is to conceptualize the paradigm of meaningful innovation (MI) by exploring the theoretical basis, identifying its core concepts and key processes, and supporting it with evidence from leading world-class enterprises.

Based on a systemic literature review on the evolution of innovation paradigms, this study builds a conceptual framework to explicate the core concepts and process of MI. Moreover, a horizontal embedded case study of GREE electric appliances is conducted to further enrich, refine and support the proposed framework.

The main finding of this study is that MI could be regarded as a process of integrating innovation elements (resources, capabilities, systems, etc.) with internal and external innovation meaning to obtain outcomes with both economic value and social significance. As a “long-termism” paradigm with meaning identification and conversion as its core, MI is driven by the collaboration of “deductive mechanism” and “reflective mechanism.”

Based on the previous studies concerning innovation paradigms on the internal and external meaning, this paper proposes an integrated framework of MI. In this framework, enterprises can consider internal and external meanings through deductive and reflective mechanisms, to better coordinate resources, capabilities, institutions, markets and other factors to achieve higher innovation performance.

For those who have read and appreciated that classic work The Development of Aircraft Engines and Fuels by Schlaifer and Heron published last year this little book on ‘Performance’ provides in neat form the theoretical basis on which the aero piston engine is founded.

This new welding tool is intended for butt‐welding wires, particularly aluminium and copper, from 0·036 inches to 0·064 inches in diameter. It is a recent addition to the range of equipment made by the General Electric Co. Ltd., for cold pressure welding. With this technique, which was developed at the G.E.C. Research laboratories, aluminium and copper wires can be welded by pressure alone, no heat being required; the joints obtained have a mechanical strength and an electrical conductivity equivalent to those of the parent wire. Certain aluminium alloys such as Silmalee can also be welded in this way. The technique was developed by the G.E.C. as a convenient method of joining aluminium conductor which is now being used on an increasing scale. A second welding tool covers the welding of wires from 0·080 to 0·144 inches.

Green building is a relatively new concept with limited applications in property development in South Africa. The objectives of this study are therefore threefold: identify key green building principles considered by property developers, establish the benefits of implementing the principles and determine the barriers to its applications.

The study adopted a case study of two Green Star South Africa (SA)-certified buildings in Sandton, Johannesburg. These are Alexander Forbes building, and Ernst & Young Eris Towers. The two certified buildings were purposefully selected because of the insightful information they provide regarding application of green building principles. The main themes investigated in the cases are environmental awareness, green building principles applications, as well as benefits and barriers of green building. A total of six interviewees from the contractors', property developers', environmental/green building consultants' and sustainability consultants' organizations who were involved in the implementation of green building principles in the two cases provided the qualitative data for the study. The qualitative data were supplemented with data relating to the two case studies obtained from the ‘Earth Works for a Sustainable Built Environment’. The interviews were arranged over a period of two months, and each interview took between 20 and 30 minutes. Analysis of the data was done through a phenomenological interpretation of the qualitative opinions expressed by the interviewees.

Key green building principles comprising energy efficiency, water efficiency, resource efficiency, occupants' health and well-being and sustainable site development were implemented in the two cases. The fact that the buildings were rated 4-star enabled inference to be drawn that the implementation of the principles was less than 60 per cent. Energy efficiency of 35 per cent indicated in Case I suggests that the level is consistent with the South African green building standard of 25 per cent to 50 per cent. However, the energy and water efficiency assessment of the building were based on projections rather than on ongoing monitoring and evaluation of the buildings' performance. Moreover, perceived saving in operational cost was identified as dominant driver to green building principles implementation. Conversely, lack of government incentives and absence of reliable benchmarking data regarding performance of green buildings were major barriers to its full implementation.

The findings of this study provide important implications to the developers and government on the application of green building principles. In the first place, the evidence that initial high cost premium could be off settled by long- term saving on operational costs as a result of use of local materials, energy and water savings as well as use of recycled material, as implemented in the two case projects, would improve investment decision in green building by developers. The understanding of the drivers and barriers to implementation of green building principles also has implications for guiding government policies and programmes towards green building.

The significance of this study stems from the fact that limited studies, especially in the South African context, have indicated the drivers and barriers to the implementation of green building principles. The case study approach adopted gave a novelty to the study by providing hands-on information from the stakeholders who were known to have played specific roles in the application of green building. The findings indicated that initial high cost premium was not a consideration in developers' choice of green building which justifies the possibility of a costlier product when factors such as environmental sustainability benefit is considered to be ultimate. The study thus suggests further research involving larger cases on energy efficiency, water efficiency and costs of green buildings compared to the conventional type to bring the findings to a broader perspective and assist to benchmark data for green building assessment.

This case study has been developed based on the primary data obtained through a series of interviews held with the senior management of Cargills, and the secondary data obtained from the company’s corporate website www.cargillsceylon.com/,annual reports and publicly available sources of information such as newspaper articles.

This case study focuses on the strategic responses employed by Cargills (Ceylon) PLC – a leading business conglomerate in Sri Lanka – in response to the challenges posed by the COVID-19 pandemic. The duration of this case study is from January 2020 to September 2021. The case study particularly examines the key business sectors of Cargills (Ceylon) PLC – retail, food manufacturing and quick service restaurants – which elaborate on the change management practices and strategies deployed by the company in each of these sectors during this challenging period. This study is based on the primary data gathered from the interviews held with the Cargills (Ceylon) PLC team, and the secondary data obtained from the corporate website of Cargills (Ceylon) PLC. This case study is most suitable to be taught in academic courses related to strategic change management.

The case is most suited to be discussed with undergraduates (3rd year and 4th year) following business and management studies related disciplines. While the pivotal area around which the case has been developed is strategic change management, covering environmental analysis, strategic analysis and process of change management, the case could also be used in strategic management classes, to discuss environmental analysis, strategic planning approaches and business and corporate level strategies.

CSS 11: Strategy.

In this paper, a numerical scheme is provided to predict and approximate the multiple solutions for the problem of heat transfer through a straight rectangular fin with temperature-dependent heat transfer coefficient.

The proposed method is based on the two-point Taylor formula as a special case of the Hermite interpolation technique.

An explicit approximate form of the temperature distribution is computed. The convergence analysis is also discussed. Some results are reported to demonstrate the capability of the method in predicting the multiplicity of the solutions for this problem.

The duality of the solution of the problem can be easily predicted by using the presented method. Furthermore, the computational results confirm the acceptable accuracy of the presented numerical scheme even for estimating the unstable lower solution of the problem.

An independent pilot scheme might be the best means of promoting the development of closed‐circuit television in British education concludes this article by a correspondent. It certainly seems true that its rapid growth will depend as much on imaginative exploitation as on greater financial or technical attractiveness. The scope for imagination in applying it to technical education and training is wide.