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Describes the historical limitations to full automation and the recent developments in technology and its application that now make full automation possible. Discusses the various layers of control from senior management down to the assembly level and the flow of information up, down and across these layers.

This paper aims to introduce a novel method for the analysis of open cell porous components fabricated by laser-based powder bed metal additive manufacturing (AM) for the purpose of quality control. This method uses photogrammetric analysis, the extraction of geometric information from an image through the use of algorithms. By applying this technique to porous AM components, a rapid, low-cost inspection of geometric properties such as material thickness and pore size is achieved. Such measurements take on greater importance, as the production of porous additive manufactured orthopaedic devices increases in number, causing other, slower and more expensive methods of analysis to become impractical.

Here the development of the photogrammetric method is discussed and compared to standard techniques including scanning electron microscopy, micro computed tomography scanning and the recently developed focus variation (FV) imaging. The system is also validated against test graticules and simple wire geometries of known size, prior to the more complex orthopaedic structures.

The photogrammetric method shows an ability to analyse the variability in build fidelity of AM porous structures for use in inspection purposes to compare component properties. While measured values for material thickness and pore size differed from those of other techniques, the new photogrammetric technique demonstrated a low deviation when repeating measurements, and was able to analyse components at a much faster rate and lower cost than the competing systems, with less requirement for specific expertise or training.

The advantages demonstrated by the image-based technique described indicate the system to be suitable for implementation as a means of in-line process control for quality and inspection applications, particularly for high-volume production where existing methods would be impractical.

This paper aims to present an investigation into the variation of scan vector hatch rotation strategies in selective laser melting (SLM), focussing on how it effects density, surface roughness, tensile strength and residual stress.

First the optimum angle of hatch vector rotation is proposed by analysing the effect of different increment angles on distribution of scan vectors. Sectioning methods are then used to determine the effect that the chosen strategies have on the density of the parts. The top surface roughness was analysed using optical metrology, and the tensile properties were determined using uni-axial tensile testing. Finally, a novel multi-support deflection geometry was used to quantify the effects of rotation angles on residual stress.

The results of this research showed that the hatch rotation angle had little effect on the density, top surface roughness and strength of the parts. The greatest residual stress deflection was measured parallel to unidirectional scan vectors. The use of hatch rotations other than alternating 90° showed little benefit in lowering the magnitude of residual stresses. However, the use of rotation angles with a good suitability measure distributes stresses in all directions more evenly for certain part geometries.

All samples produced in this work were made from commercially pure titanium, therefore care must be taken when applying these results to other materials.

This paper serves to increase the understanding of SLM scanning strategies and their effect on the properties of the material.

The purpose of this paper is to detail the design and first use of a force transducer device to study the development of forces during the laser-powder bed fusion (L-PBF) process from which residual stresses can be inferred.

The proposed novel device consists of an array of load cells for in-situ measurement of forces over time during the L-PBF additive manufacturing process. Measurements of the developed forces layer by layer were recorded in a first build using a 67-degree rotating scan strategy using Inconel 625 build material.

Preliminary experimental results from in-situ measurements using a 67-degree rotating scan strategy showed that the forces induced in the first five layers represented approximately 80% of the maximum on completion of the build and were distributed such as to induce concave deformation of the part, i.e. tension in the centre and compression at the edges of the part.

This paper describes a novel device for in-process measurement of the spatial distribution and time-varying nature of the forces induced during the L-PBF process as well as an evaluation of the residual forces following the completion of the build.

The following annotated bibliography of materials on orienting users to the library and on instructing them in the use of reference and other resources covers publications from 1980. Several items from 1979 were included because information about them had not been available in time for the 1980 listing. Some entries were not annotated because the compiler was unable to secure a copy of the item.

Behavior problems are common in toddlers and preschoolers. Richman, Stevenson, and Graham (1975) identified difficulties with eating, sleeping, toileting, temper, fears, peer relations, and activity as typical in this young population. While all young children should be expected to experience behavior problems as part of their normal development, an ongoing challenge in the field has been to determine when these “normal” developmental problems rise to the level of being considered “clinical” behavior problems (Keenan & Wakschlag, 2000). For example, when does a two-year-old child's tantrum behavior, a three-year-old's urinary accidents, and a four-year-old's defiance become clinically significant? To answer these questions, clinicians must examine the frequency, intensity, and durability of these difficulties, their potential to cause injury to the child or others, the extent to which they interfere with the child development, and the degree to which they disrupt the lives of their siblings, caregivers, peers, teachers, and others.

THE centenary celebration is that of the apparently prosaic public library acts ; it is not the centenary of libraries which are as old as civilization. That is a circumstance which some may have overlooked in their pride and enthusiasm for the public library. But no real librarian of any type will fail to rejoice in the progress to which the celebration is witness. For that has been immense. We are to have a centenary history of the Public Library Movement—that is not its title—from the Library Association. We do not know if it will be available in London this month; we fear it will not. We do know its author, Mr. W. A. Munford, has spent many months in research for it and that he is a writer with a lucid and individual Style. We contemplate his task with a certain nervousness. Could anyone less than a Carlyle impart into the dry bones of municipal library history that Strew these hundred years, the bones by the wayside that mark out the way, the breath of the spirit that will make them live ? For even Edward Edwards, whose name should be much in the minds and perhaps on the lips of library lovers this month, could scarcely have foreseen the contemporary position ; nor perhaps could Carlyle who asked before our genesis why there should not be in every county town a county library as well as a county gaol. How remote the days when such a question was cogent seem to be now! It behoves us, indeed it honours us, to recall the work of Edwards, of Ewart, Brotherton, Thomas Greenwood, Nicholson, Peter Cowell, Crestadoro, Francis Barrett, Thomas Lyster, J. Y. M. MacAlister, James Duff Brown and, in a later day without mentioning the living, John Ballinger, Ernest A. Baker, L. Stanley Jast, and Potter Briscoe—the list is long. All served the movement we celebrate and all faced a community which had to be convinced. It still has, of course, but our people do now allow libraries a place, more or less respected, in the life of the people. Librarians no longer face the corpse‐cold incredulity of the so‐called educated classes, the indifference of the masses and the actively vicious hostility of local legislators. Except the illuminated few that existed. These were the men who had the faith that an informed people was a happier, more efficient one and that books in widest commonalty spread were the best means of producing such a people. These, with a succession of believing, enduring librarians, persisted in their Struggle with cynic and opponent and brought about the system and the technique we use, modified of course and extended to meet a changing world, but essentially the same. Three names we may especially honour this September, Edward Edwards, who was the sower of the seed; MacAlister, who gained us our Royal Charter ; and John Ballinger, who was the person who most influenced the introduction of the liberating Libraries Act of 1919.

How do you measure existing fleet performance, and improve it by better scheduling techniques? How do you exercise effective control over both driver and vehicle? These were some of the points discussed in a seminar organised by consultants Drew McConkey, held recently in Manchester. It was attended by senior management of companies in the UK and the Republic of Ireland which included food wholesalers, supermarket multiples, and grocery and confectionery manufacturers. The seminar was presented by Ralph Drew, Rob McConkey, and members of the staff of DMA.

Perhaps the most remarkable event in the US medical market in the last ten years has been the astonishing growth of the new kinds of health‐care delivery systems that are collectively known as health maintenance organisations (HMOs). Indeed, they are now posing a serious threat to the conventional insurance sector which has traditionally covered most Americans. According to data collected by the US Department of Health and Human Services and the Minnesota research foundation, InterStudy, some 18.9 million people were enrolled in an HMO in June 1985, so that the 400 HMOs then in existence accounted for roughly nine per cent of the health‐care market. Today's figures are undoubtedly higher, and one New York investment company expects that ‘by 1990, 75 million people, or 30 per cent of the population, will be members of HMOs’, with the organisations achieving ‘membership expansion and revenue growth of 30–40 per cent a year’