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FLUID SEALING research at BHRA Fluid Engineering has its roots in the early years following the 1939–45 war. In 1945 the then Ministry of Aircraft Production felt that the equipment designer needed sound, basic information on the way hydraulic jack seals functioned and the factors affecting their performance. D. F. Denny was therefore seconded to Imperial College, London, to undertaken programme of research on reciprocating oil seals, which resulted in the publication of a 120‐page volume: “The sealing mechanism of flexible packings”, recently reprinted to meet a continuing demand.

The need to confine fluid within a container without leakage is a problem to be found throughout the whole of the engineering industry. In many cases there is no difficulty in making suitable leak‐tight joints, even between moving parts of machinery, but where factors such as vibration, high sliding speeds or uncertain clearances are involved, or where the liquid is at very high temperature or pressure, the operating conditions imposed on the seal may be very severe. Such conditions are now being met in the atomic energy, chemical and power generation industries, and progress is at times delayed solely due to sealing problems. In the branch of engineering concerned with lubrication of bearings the high temperatures imposed on equipment in turbines, aircraft and rockets have created new problems of sealing.

Phosphating mild steel causes the surface to be etched into a network of microscopic channels 0.0004 to 0.0008 in. deep, the phosphate crystals being located on the intervening high spots. With this type of surface, running‐in is both rapid and safe and low friction conditions are soon established. The phosphate crystals do not act as a solid lubricant in the same sense as graphite or M0S2; initial friction is higher and final friction is much lower. Friction of MoS2, for example decreases with rubbing by a factor of 4, from 0.2 to 0.05, whereas the friction of phosphated steel decreased by a factor of 60, from 0.3 to 0.005. In addition, the final friction of the run‐in phosphated surface depended on temperature and pressure in a manner characteristic of ‘thin film’ fluid lubrication, not ‘boundary’ or ‘solid’ lubrication.

The Minister of Technology, Mr Anthony Wedgwood Benn, has appointed Captain A. A. Murphy, R.N., as Director of Guided Weapons Research and Development (Naval) Branch in the Ministry of Technology. He succeeds Captain K. A. W. Pilgrim, R.N., who is returning to the Ministry of Defence.

This paper aims to present the mixed elastohydrodynamic lubrication (EHL) model and obtain the leakage characteristics for the skeleton reciprocating oil seal.

The model consists of a finite element analysis of the contact pressure, a fluid mechanics analysis of the fluid film, a contact analysis of the asperity contact pressure, a deformation analysis of the seal lip and an iterative numerical simulation process.

Simulation results show that the leakage is in direct proportion to the seal roughness and speed, and in inverse proportion to the fluid viscosity. Comparisons with the experimental results verify the validity of the mixed EHL model.

This study provides a helpful method to calculate the leakage of the skeleton reciprocating oil seal, which shortens its development cycles.

A report is provided of an evaluation of two “Senior Colleges” designed to offer viable alternatives to traditional secondary education for students above the age of compulsory schooling. The evaluation involved several researchers working independently and information collected using a variety of both quantitative and qualitative methods (including student and staff interviews and questionnaire surveys, nominal group procedures with staff and administration of instruments assessing student perceptions of classroom‐level and teacher perceptions of school‐level environment). The most striking finding emerging from almost every aspect of the evaluation was the success of the Colleges in creating a positive ethos for both students and staff. Some of the areas of concern which were identified included a relatively low level of student cohesiveness, confusion about the purpose of the Colleges, the distracting behaviour of some younger students and staff's conditions of service.

The research fields of consumer behaviour and neurology are connected to the emerging subject of neuromarketing. The learning of how the human mind reacts to marketing stimulus is called neuromarketing, which integrates concepts from neuroscience and economics. It looks for the underlying brain mechanisms and affective states that shape the behaviour of consumers. Neuromarketers use methods like eye tracking, biometrics, brain imaging (fMRI and EEG) and eye tracking to try and understand how consumers make decisions, what grabs their attention and how they emotionally interact with companies, products and ads. Market grooming is the process of creating and manipulating the existing market towards a specific product, service or idea. It is the practice that helps the marketer to groom the product through various stages of marketing, be it market research, product development, advertising campaigns or creating favourable conditions for the product. All practices are performed to groom the market for a specific product, when they are combined with neuromarketing, it becomes a perfect blend for the success of product in the actual market. The study concludes that market grooming along with neuromarketing can present a significant potential for enhancing the understanding of consumer decision behaviour by increasing the validity and precision of assessing customer responses to marketing activities.

THE ‘Theory of Limit Design’ is a theory whose philosophy and methods will be familiar to most aeronautical engineers. The term ‘Limit Design’ may not be familiar and so it is probably necessary, before making com‐ments upon the theory, to give a short résumé.

The landscape of learning and teaching is changing through the recognition of a diversity of learning types, new student generations as well as advances in technology and theory in education. While claims for interdisciplinary research and inquiry-based approaches, as well as integration of new media and technologies are at the heart of current discourses on teaching and learning, most educational activities still take place in a conservative format of the hierarchical teacher–student relationship in rather traditional educational facilities. As an architect and anthropologist, but most of all, as an academic who is devoted to teaching and research, I believe in teaching and learning experiences that are based on theoretical and methodological explorations in different disciplines in order to develop practical, research and critical thinking skills among the students. Students are motivated and engaged when they understand why information is important for them. Through an inquiry-based approach, abstract information becomes tangible and contextualized. In this chapter, I will first discuss common characteristics of our learners, today’s generation of students (the Millennials). Second, I will conceptually locate my approach to teaching among inquiry-based approaches such as Situated Learning, Learner-centered Teaching and Universal Design for Learning, which I see as complementary to each other. Third, I will explain my course design and give an account of two courses as examples for Inquiry-based Learning in action. Although these courses address architecture students, the Inquiry-based Learning and teaching experiences from these courses will inform a larger, more general audience interested in the subject matter.

Immersive virtual reality (IVR) has been frequently proposed as a promising tool for learning. However, researchers have commonly implemented a plethora of design elements in these IVR systems, which makes the specific aspects of the system that are necessary to achieve beneficial outcomes unclear. Against this background, this study aims to combine the literature on presence with learning theories to propose that the ability of IVR to present 3D objects to users improves the presence of these objects in the virtual environment compared with 2D objects, leading to increased learning performance.

To test this study’s hypotheses, the authors conducted a 2 (training condition: approach vs avoid) x 2 (object presence: high vs low) between-subjects laboratory experiment that used IVR with 83 female participants.

The results support this study’s hypotheses and show that training with high object presence leads to greater reactions to cues (chocolate cravings) and improved health behaviour (chocolate consumption).

This study shows that increased object presence leads to unique experiences for users, which help reinforce training effects. Moreover, this work sheds further light on how immersive computer technologies can affect user attitudes and behaviour. Specifically, this work contributes to IVR research by showing that learning effects can be enhanced through an increased degree of object presence.