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An examination of the advantages of fail safe design and present non‐destructive testing techniques, and the importance of facilitating inspection at the design stage. THE introduction to this paper justifies in depth the case for fail safe philosophies in aircraft structural design. The advantages include improved safety, weight savings, the full availability of the potential fatigue life of each individual aircraft in the fleet, protection against accidental damage in service and manufacturing errors, together with a good resale value.

THE British aircraft industry will only survive if it is competitive in the world's markets. This applies in both the civil and military fields. Since the main function of an aeroplane is to provide the most economic means of transportation — or weapons system — any symposium on any manufacturing technique must regard the value of engineering aspect as paramount. Thus, R. & D. into welding is not just a pleasant academic exercise and it must be justified by its ability to provide more economic aircraft.

THE development of synthetic resin adhesives has proceeded very fast since about 1937 when the first urea formaldehyde wood glues were being produced on a pilot scale. The excellent resistance of these materials to weathering conditions has enabled very considerable advances in structural design both in wooden structures and rather more recently in metal aircraft. These synthetic resin adhesives are basically ‘thermosetting’, that is to say, they harden by the addition of catalysts or by the application of heat, the chemical process which takes place being irreversible and not dependent upon the evaporation of solvents. This concept leads not only to good weather resistance, but also to the practicality of sticking together non‐porous materials such as metal. The first use of bonding of mstal in aircraft structures was in the de Havilland Hornet in 1943,1 and since then bonding has proved its advantages over other methods of joining for both primary and secondary structures. Other new methods of fabrication have appeared since that time and the requirements for structures in terms of loading and environment have changed considerably; but both mctal‐to‐metal bonding and its newer partner honeycomb sandwich show signs of much more extensive use in the future. These two most important applications of synthetic resin adhesives in modern aircraft will now be considered.

Vol. XVII, No. 2, or this scries begins with the 1958 William M. Murray Lecture on ‘Mechanics applied to Creep Testing’ by N. J. Hoff. The lecture surveys the factors making the analysis of structures under creep conditions more difficult than under conditions where linear clastic laws are obeyed. Empirical creep laws are reviewed and the dangers of extrapolation pointed out. For complex states of stress a law is recommended based on the assumptions that principal axes of stress and strain coincide and that principal stress and strain components are in the same ratio. It is shown that slight inaccuracies in the measurement of stress, fluctuations in stress and temperature, and changes in specimen geometry, may all contribute appreciably to the scatter of test results, in addition to the effects of lattice defects and intcrcrystalline bonds. The stress distribution in redundant structures will be different under creep and clastic conditions; an analogue method for analysing the former condition, using variational principles is outlined. The problem of determining stress distribution when the condition is intermediate between fully clastic and one of steady creep, is even more difficult. Some simple examples are discussed. The final section of the paper deals with instability in the creep tensile test, and with creep buckling.

THE origins of the Argosy freighter lie in Operational Requirement No. 323, issued just ten years ago, for a medium transport aircraft for R.A.F. Transport Command which would be capable of carrying payloads up to 10,000 lb. over stage lengths up to 1,500 nautical miles. Since the Ministry was not prepared to pay the total development costs of the rear‐loading, twin‐Eland AW.66 proposal, Armstrong‐Whitworth (now an integral part of Hawker Siddeley Aviation Ltd.) investigated the civil potential of the aircraft only to find that a four‐engined aircraft with forward end loading was much preferred. A few months later, the company was informed that the Treasury could not support the military requirement and so the company revised the project completely to meet the needs of the growing civil air freight market.

The prevalence of obesity in China is currently one of the lowest in the world, but it is increasing, particularly in urban areas. The incidence of obesity in China is approximately four to five times lower than in the UK and USA respectively. Several dietary studies have found that dietary fat consumption in China is lower than in Western countries, but is currently increasing. In addition, Chinese in more affluent countries such as Hong Kong, Taiwan, and Singapore, and Chinese immigrants in the USA are consuming greater amounts of dietary fat than Chinese in China. This increased intake of fat in Chinese is probably due to transition from the traditional Chinese eating patterns to those typical of Westerners. The change in overall dietary intake is likely to have an impact on obesity, health and economy of these nations. This is an appropriate time to examine the relationship between diet and obesity with special reference to Chinese communities in different parts of the world.

This article seeks to augment understanding of the rise of psychological interpretations of the child in New Zealand, and suggest refinements to McDonald’s typology, with reference to changing religious values and priorities in the years before World War II. In particular, it considers patterns of religious education, with special reference to changing representations of Jesus for children during this time. Consideration of this material indicates that psychological approaches to childhood played an important role in shaping religious education throughout these years. Though noteworthy in itself, this influence highlights the extent to which interest in scientific and psychological understandings of the child had been growing more generally since the beginning of the twentieth century. Indeed, it provides a broader context for understanding the post‐war expansion of psychological approaches to children. Insofar as psychological interpretations of childhood were paradigmatic after 1945, this occurred because such approaches had been disseminated and acquired sufficient legitimacy in preceding years.

An extensive research base supports the positive effects of self-monitoring interventions on a number of student outcomes, both academic and behavioral. While the vast majority of this research base relied on traditional paper-and-pencil forms of self-monitoring, advances in technology have created significant opportunities to develop technology-based self-monitoring (TBSM) systems that may offer a number of benefits in terms of efficiency and data management, storing, and graphing. Technology-based self-management applications have evolved and been studied extensively in health-related fields, but research and development for such applications is only beginning in the field of education. In this chapter we (1) provide a brief overview of the literature on traditional forms of self-monitoring, (2) examine how educators and educational researchers may apply lessons learned about TBSM from the medical field, (3) summarize emerging literature on TBSM for students with or at risk for emotional/behavioral disorders in particular, and (4) offer suggestions for future research and development in TBSM.

Bullying is a complex phenomenon that is grounded in intricate interactions between an individual and the social and environmental systems that surround the individual. At the present time, all 50 states and the District of Columbia have adopted bully prevention legislation to reduce the prevalence among school-aged youth. Unfortunately, bullying is associated with adverse long- and short-term outcomes, where students with disabilities, including those with behavioral disabilities, may be at escalated risk for involvement and difficulty navigating the effects of prolonged exposure to bullying. Given the complexity of bullying, several participatory roles have been established to help guide identification and intervention delivery by recognizing the reciprocity between bullying and victimization. Most importantly, interventions should be situated within a multitired or component framework and grounded in skill development, where bully prevention programming is delivered to all students based on individual need. By recognizing the risk characteristics and understanding the various student profiles, especially as they related to youth with disabilities, schools can development, adopt, and implementing prevention programming that is designed to simultaneously increase academic, functional, and behavioral development, while decreasing bullying involvement.

Alternative Education Placements (AEPs) are unique and complex settings that serve students with varieties of needs and strengths, though in practice such settings may be used most frequently to serve students with serious challenging behavior. Although research supports a number of individual interventions for students with emotional and behavioral disorders (EBD), including intensive, individualized interventions, less is known about adapting such interventions for AEPs, and especially about the potential for AEPs to adopt a flexible, positive, multitiered framework for behavior and school climate. Emerging evidence suggests that Positive Behavioral Interventions and Supports (PBIS) can be integrated into alternative education settings with careful planning. This chapter provides (1) an overview of AEPs, (2) a description of six steps recommended for integrating PBIS into AEPs, and (3) a brief overview of recent literature regarding PBIS in AEPs.