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The publication of the fourth edition of Care and Maintenance of Aircraft now includes a new chapter, entitled “Aeroplane Timbers,” by Mr. A. W. Seeley, which constitutes another valuable addition to the instructive information to aeronautical engineers, etc., that has been incorporated in this publication since its inception.

ALTHOUGH the modern tendency in aeroplane construction is to produce an all‐metal machine, the time has not yet come when we can definitely say that this or that machine is entirely of metal, there being still a fair proportion of the structure of most light aeroplanes in which wood plays a very important part, both from the point of view of the greater facilities existing for repair and the lesser cost of production.

The purpose of this paper is to assess a phenomenological zero‐dimensional model (0‐D model) in order to evaluate both the in‐cylinder tumble motion and turbulence in high‐performance engine, focusing on the capability and sensitivity of the model.

The study was performed using a four‐valve pentroof engine, testing two different intake ports. The first one was a conventional port and the second one was design in such a way to promote tumble. CFD simulations for admission and compression strokes under different engine conditions were carried out. Then, the in‐cylinder entrance mass and mean velocities from CFD were imposed as boundary conditions in the 0‐D model.

Marked discrepancies between 0‐D model and CFD results were found. As expected, for the original port, CFD results displayed a poor tumble generation during the admission period. It was followed by a fast degradation of the tumble momentum along the compression stroke due to it was not dominant over the other two momentum components. 0‐D model overestimated the entrance‐tumble but underestimated the vortex degradation along the compression stroke, resulting in higher tumble predictions, thereby it is not recommended for low‐tumble engines. As for the modified port, 0‐D model assumptions were closer to the in‐cylinder flow field from CFD, but results underestimated the entrance‐tumble during the intake stroke and predicted excessive tumble at the end of the compression stroke. Summarizing, 0‐D model neither showed sensitivity to changes in the intake port because of the scarce information about the entrance‐flow field nor it was not suitable to evaluate the tumble degradation.

The limitations of the current model were highlighted, given possible guidelines in order to improve it.

As the most common aeronautical timber is SITKA or silver spruce, its main deficiencies will be of special interest. The essential properties and defects appearing in converted timber, i.e., at planed surfaces (rough portions are unsuitable for timber selection) are as follows:

IN wooden aeroplane manufacture, the technique to be adopted in the workshop is more or less a matter of the engineering experience gained by mistakes and disappointments.

The purpose of this paper is to carry out a detailed investigation of the mechanisms operating during decision making by the honey bee swarm, which is now considered to be one of the best examples of collective decision making outside the human domain.

This investigation is based on a review of the last 60 years’ published literature about swarm behaviour. It introduces a different perspective to the work by utilising a cybernetic model of a self-organising information network to analyse the findings of this body of research.

Scout bees evaluating potential nest sites accumulated support for their site by differential net recruitment, so the total scout numbers present at each site was a good measure of the total evidence in favour of the site and hence the relative probability of choosing it as the swarm’s new home. The accumulation of evidence continued at a number of alternative nest site locations until a critical quorum threshold was sensed at one of them. The first alternative to reach the threshold was chosen as the preferred nest site. Quorum scouts then prepared the swarm for departure and steered it to its new home.

Swarm decision making has not been modelled as a self-organising information network before. This novel approach reveals how a combination of network modifications, self-amplification, self-attenuation, cross-inhibition, integration and quorum mechanisms together contribute towards accurate group decision making.

The purpose of this paper is to investigate how a viable system, the honey bee swarm, gathers meaningful information about potential new nest sites in its problematic environment.

This investigation uses a cybernetic model of a self-organising information network to analyse the findings from the last 60 years published research on swarm behaviour.

Nest site scouts used a modified foraging network to carry out a very thorough survey of the swarm’s problematic environment, providing the swarm with a considerable diversity of potential nest sites for consideration. The swarm utilised a number of randomly recruited groups of scouts to obtain numerous independent opinions about potential nest sites, each privately evaluated, publicly reported and repeatedly tested by new recruits. Independent evaluation of site quality was balanced by interdependent reporting of site location. Noise was reduced by integration over a large number of individual scouts and over a period of time. The swarm was therefore able to reduce potential sources of bias, distortion and noise, providing it with comparatively reliable information for decision making.

Information gathering by a honey bee swarm has not previously been modelled as a self-organising information network. The findings may be of value to human decision-making groups.

Despite the exponential spread of the British Empire by the late nineteenth century, there remained in England a continued indifference to “the Empire”. In 1883, J.R. Seeley, Regius Professor of Modern History in the University of Cambridge, had expressed concern because ‘we think of Great Britain too much and of Greater Britain too little’. People had to rethink their understandings of nation and empire, he suggested, and steps had to be taken to modify what he saw as a ‘defective constitution’. Seeley’s lecture series had prompted debate about ‘the imperial question’, but the ‘anomalous political arrangements’ and the reluctance of the people to think imperially persisted. Insularity was not exclusive to the people in Britain, however. Because of their preoccupation with their own local affairs, it was suggested, there had been little opportunity for people from other parts of the empire to devote much time to the larger questions of imperial and common citizenship.

This study provides a framework for comparing construction management contracts in the UK and the US construction practices. It starts by reviewing previous studies on UK and US contracting practices and explores the main delivery methods, inform of comparison with construction management contracting systems. It examines construction management contracting types, processes and procedures and interaction between the construction manager and other stakeholders. This study was based on a literature review and the result shows the similarities and differences between the American and British CM systems within each practice and between both practices; the distribution of responsibilities and risks both in pre‐construction and during the construction stages; and allocation of responsibility in both practices.

The basis of this study is Kelley’s (1992) two-dimensional model, which measures five follower types. Previous investigations did not support the validity of Kelley’s model. Although the model is utilized in research, the validity and reliability of the Kelley Followership Questionnaire (KFQ) is still in question. In this study, the KFQ validity was tested after revision of the instrument. Factor analysis revealed a three-factor model disputing the theorized two-factor model. Factors of the KFQ-R convergent validity were supported by significant correlations with critical thinking disposition and work engagement scales. This research project is intended to promote the study of the followership construct.