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SUMMARY The main overall problems associated with transparencies for manned supersonic and hypersonic aircraft are considered. Civil and military concepts are compared in relation to aircraft performance requirements and the reasons for the continuing need for optical transparencies are enumerated. Aircraft performance requirements and typical flight plans show the necessity for designing the transparencies to withstand a considerable range of environmental conditions in addition to the aerodynamic dictates in relation to size, position and shape. These conditions are listed and design feature considerations are discussed in some detail with particular accent on the thermal problems. Reference is made to certain organic and inorganic materials for the basic glazings and the problems associated with the ‘marrying’ of these materials with retaining frame members are discussed. Detail proposals are made for typical windscreen and canopy assemblies. Brief reference is made to the poor reliability shown by many transparencies in present‐day modern aircraft which indicates the need for revision of certain existing test requirements. The proposed new requirements will result in the development of new testing techniques although test factors might well be reduced. The paper concludes with a statement on the importance which is being given to the subject matter by the various bodies in the U.K. and the emphasis which should be placed on the need for the continuation of research and development work in this field.

THE main working documents for an inspector are specifications and drawings. Among criticisms made at the Natural Rubber Producers' Research Association symposium last year, was that there are too many specifications and I think most of us would agree. However, I think we could improve this situation considerably as far as materials are concerned, if we accepted and really worked in accordance with the fundamental principle laid down in Av.P.970 Chap. 400. This can be summarised as: ‘Specifications for critical materials need approval by D.Mat/Aviation — non‐critical materials do not need such approval’. A rider is added to the effect that non‐critical materials do not need to be inspected to such tightly drawn specifications as critical materials and in some instances commercial quality materials may be used. If one can decide therefore, which materials are critical and which are not, and this is by no means easy, we can simplify inspection procedures and possibly reduce the number of specifications. Obviously critical applications will always call for special quality specifications but it is wasteful to use such materials where they are not necessary. One docs, however, notice a tendency among specification writers to over specify and to classify specifications too highly, i.e. to seek special approval when it is not necessary. It is our view that A.I.D. supervision should be concentrated on critical materials and components and that comparatively little effort should be devoted to non‐critical items, this being left to the purchaser who would probably order standard engineering materials or even commercial quality.

THE trend to ‘hard’ trim aircraft interiors is explained and the range of available materials is surveyed. Although aesthetically and economically attractive, thermoplastic sheet materials are deficient in certain properties particularly for freighter and dual role aircraft. Against this background the HS. 748 Military Freighter version featured the use of an all G.R.P. interior which was unique in that the visible surface was a textured finish gel‐coat integral with the laminate. The design and production problems involved with this approach are discussed and an overall assessment of service experience is attempted.

This study explores the coping strategies employed by people of color in response to racial discrimination and examines how cultural norms inform these strategies.

In-depth qualitative interviews were conducted with 34 Black and Asian Americans about their experiences with racial discrimination.

Findings reveal that participants cope through humor, seeking social support on social media, from family and friends, and through avoidant coping strategies. Seeking social support from empathetic others, especially when they shared the same racial background as participants, contributes to feelings of comfort, sanity, and a sense of community. Group differences emerge in seeking family support with Black Americans more likely to seek parental support, likely because of racial socialization practices by their parents that prepared them for experiencing bias. Asian Americans preferred talking to siblings or cousins, citing a cultural gap between them and their parents.

The study underscores the importance of considering the quality of social support, not just its use, as a buffer against harms related to discrimination.

Racial discrimination is a routine experience for many people of color. This study demonstrates how the type of coping strategy matters for coping with the distress that often accompanies these experiences.

In contrast to monoracial-focused studies, this research demonstrates the convergence and divergence of coping strategies among different racial groups.

The purpose of this paper is to present a methodology to predict initial crack growth behavior of crack or notch like stress raisers in AISI 316L(N) stainless steel material subjected to monotonic loading condition.

The methodology for critical crack blunting corresponding to crack initiation in crack or notch like stress raisers is based on critical plastic strain (Epc) at a characteristic distance (lc), where uniform strain (Eu) is considered as Epc and two grain diameter is considered as lc. Further crack growth is based on parabolic crack tip opening displacement (CTOD) scheme established based on coupled experimental and FEM analysis of compact tension (CT) specimen subjected to mode-I loading condition. The FEM predicted load-displacement plots is compared with experimental result of CT specimens with different a/W ratios. It has shown that the proposed methodology could account initial crack blunting appropriately and predict the fracture load and load-displacement plots for initial crack growth regime.

The results show that for crack growth with near straight crack front, experimental data from a CT specimen of particular a/W ratio coupled with plane strain 2D FEM analysis could predict load vs displacement plots for different a/W ratios when initial crack blunting is accounted appropriately with a local damage model.

The present study is a part of developing methods to analyse fracture behavior of AISI 316L(N) SS material components used for fast breeder reactor-based power plant being built at Kalpakkam, India.

Purpose – For decades, archivists have been appraising, preserving, and providing access to digital records by using archival theories and methods developed for paper records. However, production and consumption of digital records are informed by social and industrial trends and by computer and data methods that show little or no connection to archival methods. The purpose of this chapter is to reexamine the theories and methods that dominate records practices. The authors believe that this situation calls for a formal articulation of a new transdiscipline, which they call computational archival science (CAS).

Design/Methodology/Approach – After making a case for CAS, the authors present motivating case studies: (1) evolutionary prototyping and computational linguistics; (2) graph analytics, digital humanities, and archival representation; (3) computational finding aids; (4) digital curation; (5) public engagement with (archival) content; (6) authenticity; (7) confluences between archival theory and computational methods: cyberinfrastructure and the records continuum; and (8) spatial and temporal analytics.

Findings – Each case study includes suggestions for incorporating CAS into Master of Library Science (MLS) education in order to better address the needs of today’s MLS graduates looking to employ “traditional” archival principles in conjunction with computational methods. A CAS agenda will require transdisciplinary iSchools and extensive hands-on experience working with cyberinfrastructure to implement archival functions.

Originality/Value – We expect that archival practice will benefit from the development of new tools and techniques that support records and archives professionals in managing and preserving records at scale and that, conversely, computational science will benefit from the consideration and application of archival principles.