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In the optimisation of processing parameters for additive manufactured parts using, e.g. selective laser melting (SLM) or electron beam melting, the measurement of the part densities is essential and of high interest. However, there is no common standard. Different institutes and system providers are using their own principles and guidelines. This study investigates the accuracies of the three measurement principles: Archimedes method, microscopic analysis of cross sections and X‐ray scanning.

A total of 15 test samples on five density levels (densities between 90 and 99.5 per cent) were produced using the SLM process. The samples are analysed regarding the accuracy of the measurement principles and their reproducibility taking into account influencing parameters like the buoyancy of a sample in air (Archimedes method) or different magnifications of a cross section.

The Archimedes method shows a very high accuracy (±0.08 per cent for high densities) and repeatability (±<0.1 per cent) on all density levels. In contrast to the Archimedes method, taking a micrograph of a specific cross section allows to influence the resulting density and the coefficient of variation reaches values>4 per cent. However, for low porosities, mean densities are comparable to the results of the Archimedes method even though calculated densities are typically somewhat too high. The advantage of the image guided analysis (2D and 3D) is getting more information about the distribution, size and form of pores in the part.

The findings do not only refer to metallic parts but generally to all parts having a specific porosity. The study is a contribution to the American Society for Testing and Materials initiative F42 “Additive Manufacturing Technology” and especially to the subcommittee “test methods”.

In this article a resume is given of the principal obsevations made during the course of exposure in a natural atmosphere during some twenty years, while choosing the most characteristic examples. The following points will be examined: Resistance to spray and mist of aluminium‐magnesium, aluminium‐magnesium‐silicon, aluminium‐ zinc‐magnesium, and aluminium‐copper magnesium rolled alloys, and of cast alloys; Behaviour of welds, and of contacts with steel and cement; Behaviour during immersion in the sea, and corrosion by differential aeration; Protection by anodisation. These observations have been made during exposure at the experimental stations of the Pechiney Group, in marine atmospheres at Salin‐de‐Giraud (Mediterranean), Saint‐Jean‐de‐Luz, Biarritz and Ostend, and in an industrial atmosphere at Aubervilliers.

The following classified, annotated list of titles is intended to provide reference librarians with a current checklist of new reference books, and is designed to supplement the RSR review column, “Recent Reference Books,” by Frances Neel Cheney. “Reference Books in Print” includes all additional books received prior to the inclusion deadline established for this issue. Appearance in this column does not preclude a later review in RSR. Publishers are urged to send a copy of all new reference books directly to RSR as soon as published, for immediate listing in “Reference Books in Print.” Reference books with imprints older than two years will not be included (with the exception of current reprints or older books newly acquired for distribution by another publisher). The column shall also occasionally include library science or other library related publications of other than a reference character.

The Seminar on Library Interior Layout and Design organised by IFLA's Section on Library Buildings and Equipment, and attended by people from over twenty‐two countries, was held at Frederiksdal, Denmark, in June 1980. This present article neither reports on the Seminar's proceedings, as it is hoped to publish the papers in due course, nor describes fully the Danish public libraries seen, but rather uses the Seminar's theme and the library visits as a point of departure for considering some aspects of the interior layout—the landscape—of public libraries. Brief details of the new Danish public libraries visited are given in a table at the end of the article.

The purpose of this paper is to calculate near field and far field scattering of SH waves by multiple multilayered anisotropic circular inclusions using parallel volume integral equation method (PVIEM) quantitatively.

The PVIEM is applied for the analysis of elastic wave scattering problems in an unbounded solid containing multiple multilayered anisotropic circular inclusions. It should be noted that this numerical method does not require the use of the Green’s function for the inclusion – only the Green’s function for the unbounded isotropic matrix is needed. This method can also be applied to solve general elastodynamic problems involving inhomogeneous and/or anisotropic inclusions whose shape and number are arbitrary.

A detailed analysis of the SH wave scattering problem is presented for multiple multilayered orthotropic circular inclusions. Numerical results are presented for the displacement fields at the interfaces and the far field scattering patterns for square and hexagonal packing arrays of multilayered circular inclusions in a broad frequency range of practical interest.

To the best of the authors’ knowledge, the solution for scattering of SH waves by multiple multilayered anisotropic circular inclusions in an unbounded isotropic matrix is not currently available in the literature. However, in this paper, calculation of displacements on interfaces and far field scattering patterns of multiple multilayered anisotropic circular inclusions using PVIEM as a pioneer of numerical modeling enables us to investigate the effects of single/multiple scattering, fiber packing type, fiber volume fraction, single/multiple layer(s), the multilayer’s geometry, isotropy/anisotropy and softness/hardness.

In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of material poses problems for the researcher in management studies — and, of course, for the librarian: uncovering what has been written in any one area is not an easy task. This volume aims to help the librarian and the researcher overcome some of the immediate problems of identification of material. It is an annotated bibliography of management, drawing on the wide variety of literature produced by MCB University Press. Over the last four years, MCB University Press has produced an extensive range of books and serial publications covering most of the established and many of the developing areas of management. This volume, in conjunction with Volume I, provides a guide to all the material published so far.

The two major trends in American history reference publishing, noted in last year's survey, continued throughout 1978: the refinement of past efforts and improved access, via micrographics, to elusive source materials. The genuinely new or unique reference work is indeed a rara avis, but the reason for this situation is not all that puzzling. Historians of American history and culture, each looking at a particular aspect of our past, need to gain access to a number of already existing historical records (out‐of‐print books, obscure government reports, archival records, regional studies, etc.) and publishers are merely attempting to fulfill these needs in a variety of ways. Therefore, the revision of standard sources, new titles in series, and the completion of large micrographics collections reflect the principal publishing activities of 1978. The few exceptions include the unique Dictionary of American Library Biography and the essentially new Handbook of North American Indians.

This special “Anbar Abstracts” issue of the Marketing Intelligence & Planning is split into nine sections covering abstracts under the following headings: Business Strategy; Marketing Strategy; Customer Service; Sales Management; Promotion; Marketing Research/Customer Behaviour; Product Management; Logistics and Distribution; Sundry.

This special “Anbar Abstracts” issue of the Personnel Review is split into six sections covering abstracts under the following headings: Career/Manpower Planning and Recruitment; Health and Safety; Industrial Relations and Participation; Pay, Incentives and Pensions; Performance, Productivity and Motivation; Work Patterns.

“Reference Serials” began in Reference Services Review, April‐June 1974 and last appeared in RSR, October‐December 1974. It was transferred to Serials Review with the inaugural double issue of SR, January‐June 1975, and appeared there through SR, October‐December 1978. With this issue it returns to RSR because the editors determined, after much examination, that this is where it belongs.