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MALFUNCTIONS of turboprop, turbojet and turbofan engines can be divided into two groups as follows:

EARLY in 1963, a project was initiated in co‐operation with an European airline with a purpose of starting development work for a new transducer for engine vibration monitoring. The low reliability of former pickups motivated this development work. In the course of the development, modern engine design requirements raised the need for the high temperature stability of these transducers. The development work was, therefore, based on the necessity to produce a vibration transducer with extreme high reliability, good interchangeability tolerance and useable up to approximately 600 deg. C. in practical flight operation. With regard to these requirements, a suitable technical approach seemed to be the use of the piezoelectric transducer technique, because seismic acceleration pickups working on the piezoelectric principle do not use moving parts, whereas displacement and velocity pickups, used so far, have at least one moving part, i.e. the inertial mass. Also the requirement for high temperature stability could be met by using modern crystal technology. The following chapters will expound some mechanical and crystallographic considerations in connection with such transducers, and furthermore describe some devices which are now being used in practical flight operation. Today, the concept of a piezoelectric, high temperature accelerometer with 2‐pole signal output has been commonly adopted in industrial production of transducers for airborne vibration monitoring.

Invented in late 1890s, asbestos cement sheeting rose to prominence during the post-Second World War period as a building material for low-cost housing by state housing commissions and low-income families (“fibro homes”). The adverse health effects of asbestos fibres in the building industry and home renovation activities are well documented. Fibro homes of the 1950s and 1960s are increasingly coming under the gaze of heritage studies, which brings to the fore the question of how to deal with the asbestos cement sheeting most are clad with.

This paper provides the first systematic review to assess the literature (126 papers were identified in Google Scholar and scanned for content) on the conservation management of asbestos cement sheeting in heritage properties.

Overall, engagement with the conservation management of asbestos cement sheeting in heritage properties was low, with only two sources dealing with asbestos cement sheeting in any level of detail. The studies note that if asbestos cement sheeting is in good condition, it should be left alone. Numerous conservation and repair options do exist, in particular the application of (coloured) sealants that extend the life of asbestos cement sheets and asbestos cement roofing.

This paper represents the first systematic review to assess conservation management options for asbestos cement sheeting in heritage properties.

A series of articles dealing, in as simple a way as possible, with the basic facts of lubrication, lubricants, their selection and prescription, specification, application, and testing. This series is primarily intended for students, engineering personnel who may be unfamiliar with certain aspects and others who, one way or another, are interested in this important subject.

If one consults an up‐to‐date list of approximate tests issued by a wholesale lubricating oil concern the following kind of item will be encountered : “150 Solv. Neut. Redwood viscosity at 70°F. 310″, at 140°F. 66″”. The grade number refers to a Saybolt reading and the viscosities are in Redwood seconds. But this is 19G2 and we are well in the kinematic era. Yet reference to empirical viscosity units is by no means uncommon. Brooding on this prompted the author to recall something of efflux viscometers, the transition to the capillary instrument and the persistance of an earlier tradition.

The purpose of this paper is to present a novel model for predicting the effective viscosity of nanofluids. At present, no unified model exists for the same.

The present effective viscosity model draws upon the regression analysis of carefully selected published papers covering experimental, numerical and theoretical findings.

Unlike some other models, this one is reliable and has a good level of accuracy. This model has been assessed in a numerical investigation using a 3D horizontal pipe, and the results are presented.

This is a new model for predicting the effective viscosity of nanofluids. The proposed model has been tested in a 3D horizontal pipe, and the predicted results for viscosity and Nusselt number show good agreement with the available data.

The purpose of this paper is to present the baseline results of a school development project where the aim was to improve school community staff's occupational wellbeing in co‐operation with occupational health nurses.

The Wellbeing at Your Work index form for school staff developed for the study aimed to account for occupational wellbeing and satisfaction in terms of the activities maintaining the ability to work as well as the working conditions, working community, worker and work and professional competence and the need to develop them.

The most problematic factors of occupational wellbeing were the urgency and pace of work at school and the problems in working space, postures and equipment. In addition, the activities supporting resources, including stress control, exercise, relaxation and mentoring, were inadequate at work.

The sample of school staff (n=271) consisted of 12 schools in Eastern Finland, and the results cannot be generalised widely due to the small and geographically defined sample. However, the results are suggestive for other schools elsewhere in Finland.

The content model for the promotion of occupational wellbeing presented in the article and the results obtained provide a broad and practical approach to the development of school staff's occupational wellbeing. Occupational health care services are meant to support school communities, and they should therefore provide better information of their services and develop their competence based on the content model of occupational wellbeing.

The work index form based on the content model serves as a good tool for schools and occupational health care in evaluating and developing occupational wellbeing.

The purpose of this paper is to examine and critique current approaches of higher education (HE) community concerning stakeholder engagement in the development of information and communications technology (ICT) related accessibility practice.

The approach taken to this examination is to draw on presentations, panel discussions and World Café reflections from an international symposium held in Montreal where researchers and practitioners debated two key questions as follows: have all the relevant stakeholders really been identified? Are there some stakeholders that the HE community has ignored? And what factors influence successfully distributed ownership of the accessibility mission within HE institutions?

A number of “new” internal and external stakeholders are identified and it is argued that if they are to be successfully engaged, effort needs to be invested in addressing power imbalances and developing opportunities for successful strategic silo-crossing.

The value of this paper is in critiquing the argument that all stakeholders in the development of accessible ICT in HE need to be involved, identifying a gap in the argument with respect to whether all relevant stakeholders have actually been engaged and offering insights into this omission might be rectified.