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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.

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.

Implementing and maintaining Electronic Theses and Dissertations (ETDs) program at a national level encounters numerous difficulties in particular from technical, legal, business, and financial perspective. Business model (BM) is a tool to help to address business-driven challenges, such as business feasibility and viability, as one of the important aspects. The purpose of this paper is to analyze the BM practiced by different national Electronic Theses and Dissertations (NETDs) cases.

BM of seven NETDs programs have been studied through an online questionnaire; besides, programs’ websites were observed and related documents were examined. Business model canvas (BMC) was used to describe the business rationale behind the selected cases.

Most of the NETDs programs lack a documented BM. The main value of these programs is sharing ETDs which is offered to academics through online channels; skillful staff and proper hardware/software are their main resources to do so. Furthermore, their key activities are developing hardware/software and negotiating with ETDs owners as their key partners. All these activities required huge cost which is generally covered by public funding.

This study pioneers in applying BM concept into field of NETDs. Therefore, the major contribution of this study is to provide an analysis of NETDs programs’ BM through BMC. Furthermore, the paper provides recommendations on how ETDs could be implemented in a cost effective, sustainable, and viable way.

The idea of implementing supply chain management (SCM) principles for the construction industry was embraced by construction stakeholders to enhance the sector's performance. The analysis from the literature revealed that the implementation of SCM in the construction industry enhances the industry's value in terms of cost-saving, time savings, material management, risk management and others. The construction supply chain (CSC) can be managed using the pull or push system. This chapter also discusses the origin and proliferation of SCM into the construction industry. The chapter revealed that the concept of SCM has passed through five different eras: the creation era, the use of ERP, globalisation stage, specialisation stage and electronic stage. The findings from the literature revealed that we are presently in the fourth industrial revolution (4IR) era. At this stage, the SCM witnesses the adoption of technologies and principles driven by the 4IR. This chapter also revealed that the practice of SCM in the construction industry is centred around integration, collaboration, communication and the structure of the supply chain (SC). The forms and challenges hindering the adoption of these practices were also discussed extensively in this chapter.