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Publication date: 1 June 1951

WE look before and after at the beginning of 1951. The three cardinal dates in the history of the public library movement—which is only the larger part of the national library…

39

Abstract

WE look before and after at the beginning of 1951. The three cardinal dates in the history of the public library movement—which is only the larger part of the national library service—were 1850 which saw the legal origin of the movement; 1919 when it was set free from the enforced poverty of sixty‐nine years, and 1950 when it reached what until today was its veritable apotheosis. General recognition, such as authority from the Crown to the humblest journal gave to public libraries, was something undreamed of not more than thirty years ago. Perhaps, now that some of the splendour of the commemoration has taken more sober colours, it is well to consider what was gained by it. First, the recognition is there and can scarcely be belittled by anyone hereafter; we stand on a somewhat different platform now. We have the extremely valued recognition of our colleagues from libraries overseas. From these advantages all libraries and not only public libraries will in their own way profit.

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New Library World, vol. 53 no. 6
Type: Research Article
ISSN: 0307-4803

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Article
Publication date: 1 February 1953

IT is rare nowadays to discover in the annual or other reports of libraries any reference to current losses of books. There are many sides to this, as to every problem. Formerly…

28

Abstract

IT is rare nowadays to discover in the annual or other reports of libraries any reference to current losses of books. There are many sides to this, as to every problem. Formerly it was held that a loss of one volume in an issue of a thousand was a reasonable loss; this our readers know. We do not recall a pronouncement based upon a count of stock and circulation recently. As our pages, and those of other library journals, have shown, the check and control of losses is a really costly business. Nevertheless, as long as we can remember, it has been impressed on librarians that we are custodians of a certain form of public property which we are expected to keep for as long in safety as that property retains its value. It can also be asserted that the discovery of whereabouts in the accounts of a bank a single shilling is missing may occupy hours of staff‐time; it is probably necessary to make it, and this was done a few years ago, and maybe is done now. To pose this problem nowadays, when there is so much else to be done, may be a little tactless. In the present conditions of public regard, or want of it, for the property of others, especially communal property, our eagerness to serve our people without let or hindrance, and the consequent removal of all barriers, wickets and entrance checks even in very busy libraries of large size—are we sure that we are absolved from all responsibility for the care of books?

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New Library World, vol. 54 no. 7
Type: Research Article
ISSN: 0307-4803

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Article
Publication date: 1 April 1950

H.W. GREENWOOD

There are three directions in which powder metallurgy has made outstanding contributions to the problems of efficient and economical lubrication. First, we have the porous…

54

Abstract

There are three directions in which powder metallurgy has made outstanding contributions to the problems of efficient and economical lubrication. First, we have the porous (sometimes called the self‐lubricating) bearing, then there are the steel‐backed bronze lined oil retaining bearings and bushes and the copper lead or other alloy porous bearings and lastly, powder metallurgy has provided materials for filtering oils at high speed and under considerable pressures.

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Industrial Lubrication and Tribology, vol. 2 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 May 1943

ALTHOUGH the active European and Asiatic land war has not begun so far as the bulk of the English are concerned and there are no visible signs of war's ending, advantage has been…

19

Abstract

ALTHOUGH the active European and Asiatic land war has not begun so far as the bulk of the English are concerned and there are no visible signs of war's ending, advantage has been taken by many bodies to outline their after‐war proposals. Stale as we know that simple statement to be, we want to insist again that no one should be deflected for long from this reconstruction problem on the grounds that the decisive phases of war are still before us. Improbable as it seems, peace might “break out” at any time and might be catastrophic if food, clothing, homes and employment were not available on a scale at present scarcely dreamed. All the reports on reconstruction we have seen—of the Labour Party, N.A.L.G.O., the Educationists, as well as the more national ones, the Beveridge, the Uthwatt and those, so far as they exist, of the political parties, have common factors. The imperative of the moment is to relate these and to admit without party bias, the grounds of agreement so that some sort of work may begin. If this is not done—and who is to do it?—the whole of reform may be suffocated in a mass of indigestible verbiage. Libraries are vital, we say and believe, but in the general welter of words the many words of the excellent McColvin Report will not have fair consideration we fear. Our readers know that a strong committee of the Library Association has been giving assiduous study to the much shorter statement which is to embody library aspirations. We hope that it may not be long delayed, although we recognize that undue haste might lead to prolonged repentance.

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New Library World, vol. 45 no. 10
Type: Research Article
ISSN: 0307-4803

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Article
Publication date: 2 November 2018

Jun Ni and Wuxue Ding

Determinative locating and riveting distortions are highly coupled at assembly locale. Recent methods only take every tested or assumed locating errors at the mating surface into…

219

Abstract

Purpose

Determinative locating and riveting distortions are highly coupled at assembly locale. Recent methods only take every tested or assumed locating errors at the mating surface into the process planning for the assemblies in a simple form. However, the growth of part number makes it nearly infeasible to take every locating error at every mating surface into the dimensional precision calculation. This paper aims to provide a solid riveting process planning for the reduction of practical locating-related distortions.

Design/methodology/approach

Large-scale metrology firstly measures the determinative coordinates for the locating-deviated key points. Iterative finite element (FE) analyses then calculate the riveting-related key point distortions from every rivet upsetting directions (UDs) and assembly sequence. These key points on the actual assembly contour and relative FE nodes yield two virtual planes. Virtual plane manipulation adds the riveting distortions into the locating-deviated coordinates. Finally, optimal algorithm integrates the iterative FE analyses with virtual plane manipulation.

Findings

Case studies validate that the virtual plane manipulation coincides with the test well, and the proposed method has good compensation of practical locating distortion.

Research limitations/implications

The optimized rivet UDs may be set in a chaotic distribution, which may complicate the abundant riveting operations and the assembly appearance. Therefore, the use of automatic riveting systems can overcome the operational complexity, and the industrial design of rivet UD distribution will improve the assembly appearance.

Practical implications

The optimized UDs and assembly sequence are for assembly workers or automatic riveting systems.

Originality/value

The proposed method is the first to reduce the determinative locating distortion by a novel and efficient solid riveting process planning in detail, and the solid riveting process designed is conservative and accurate for practice.

Details

Assembly Automation, vol. 39 no. 1
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 1 October 1961

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Technical Reports and Translations of the United States…

17

Abstract

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Technical Reports and Translations of the United States National Aeronautics and Space Administration and publications of other similar Research Bodies as issued.

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Aircraft Engineering and Aerospace Technology, vol. 33 no. 10
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 February 1949

B. DE GORTER

The importance of copying processes ONE of the most frequently occurring requirements in all modern human activity, be it commerce, government, research, or any other sphere, is…

27

Abstract

The importance of copying processes ONE of the most frequently occurring requirements in all modern human activity, be it commerce, government, research, or any other sphere, is the need to obtain a true copy of a document. The efficiency of the method used for copying documents has a definite influence on the overall efficiency of the undertaking concerned. Executives are therefore always on the look‐out for improved methods for copying documents. By ‘document’ is meant any visual record of information. The information may be expressed by various media, such as language, numerical data, codes, graphs, diagrams, sketches, or photographs, which may be borne on various vehicles, such as letters, memoranda, reports, drawings, tracings, blue‐prints, pamphlets, patent specifications, periodicals, books, photographic film, index cards, and punched cards.

Details

Journal of Documentation, vol. 5 no. 1
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 5 May 2015

Wichai Chattinnawat

The purpose of this paper is to apply the statistical tolerancing technique to analyze the dual responses of APFA arm height deviation with respect to next stage of disk assembly…

264

Abstract

Purpose

The purpose of this paper is to apply the statistical tolerancing technique to analyze the dual responses of APFA arm height deviation with respect to next stage of disk assembly process and simultaneously optimize and allocate the required tolerance of the responses onto its components at minimum cost of manufacturing and the quality loss.

Design/methodology/approach

The relationships between the dual responses of APFA heights and the geometric dimensions and tolerances of APFA components, and orientation of the assembled part with respect to disk assembly were first defined. The effects of the APFA orientation, and the component tolerances on the distributions and variations of the responses were derived and investigated in terms of resultant product/process performance, quality loss, and the cost of assembly. The tolerance cost-based objective function is then formulated as the combined manufacturing/assembly cost and the quality loss. Direct search method was used to find the best feasible tolerance solutions satisfying the required product performance at minimum cost.

Findings

The constructed relationship or transfer functions of the dual responses were probabilistic depending on the orientation of part with respect to the next assembly process. The Monte Carlo simulation is empirically suitable for the computation of the conditional distributions of the responses against the first-order linear approximation of component variances. The proposed solution of tolerance control plan increases the product performances, C pm, from 0.6 to be at least 1. The proposed tolerance allocation plans will reduce the amount of rework currently as high as 5 percent to at most 0.01 percent with minimally increased assembly cost.

Practical implications

This proposed methodology to design and allocate component tolerances is suitable and applicable to the APFA assembly process. The derived assembly functions of probabilistic type relating the responses to the process and component characteristics can represent the actual dynamic of assembled part better than a traditional single deterministic function developed under static concept. This presented methodology can be applied to other assembly cases where quality characteristic depends on the part dynamic.

Originality/value

This research simultaneously optimized the dual APFA height deviation responses with minimum cost of tolerance and quality loss using two different conditional distributions and transfer functions of the resultant deviations generated from dynamic of APFA with respect to disk.

Details

International Journal of Quality & Reliability Management, vol. 32 no. 5
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 1 September 2002

C. Xiong, Y. Rong, R.P. Koganti, M.J. Zaluzec and N. Wang

This paper develops the statistical error analysis model for assembling, to derive measures of controlling the geometric variations in assembly with multiple assembly stations…

1103

Abstract

This paper develops the statistical error analysis model for assembling, to derive measures of controlling the geometric variations in assembly with multiple assembly stations, and to provide a statistical tolerance prediction/distribution toolkit integrated with CAD system for responding quickly to market opportunities with reduced manufacturing costs and improved quality. First the homogeneous transformation is used to describe the location and orientation of assembly features, parts and other related surfaces. The desired location and orientation, and the related fixturing configuration (including locator position and orientation) are automatically extracted from CAD models. The location and orientation errors are represented with differential transformations. The statistical error prediction model is formulated and the related algorithms integrated with the CAD system so that the complex geometric information can be directly accessed. In the prediction model, the manufacturing process (joining) error, induced by heat deformation in welding, is taken into account.

Details

Assembly Automation, vol. 22 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 12 March 2018

Azadeh Haghighi and Lin Li

Quantifying and controlling the quality characteristics of parts produced by additive manufacturing (AM) processes has attracted significant interest in the research community…

512

Abstract

Purpose

Quantifying and controlling the quality characteristics of parts produced by additive manufacturing (AM) processes has attracted significant interest in the research community. However, to increase the sustainability of AM processes, such quality characteristics need to be assessed together with life cycle performance of AM processes such as energy and material consumption and manufacturing cost. Although a few studies have been performed for several quality characteristics, i.e. surface roughness and tensile strength, the relationship between dimensional performance and manufacturing cost is still not well known for AM processes.

Design/methodology/approach

In this paper, a comprehensive study of the dimensional performance and manufacturing cost of fused deposition modeling AM process is performed. Design of experiment technique is used, and the correlation of different cost components and the dimensional accuracy of parts are statistically studied.

Findings

The optimum process parameters for simultaneously optimizing the dimensional performance and manufacturing cost are identified. The analysis shows that as opposed to traditional manufacturing processes, obtaining a better dimensional performance is not necessarily associated with higher cost in the AM processes.

Originality/value

Almost no study and analysis for the combined dimensional performance and manufacturing cost has been performed for AM processes in the literature. It is known that within the context of traditional manufacturing processes, a natural trade-off governs the pursuit of higher dimensional performance and the manufacturing cost. However, as the AM process has a different nature compared with traditional manufacturing processes, the relationship between manufacturing cost and dimensional performance of parts has to be studied. Understanding this relationship will also help to establish a cost-optimal and sustainable tolerance allocation strategy in assemblies with AM components.

Details

Rapid Prototyping Journal, vol. 24 no. 2
Type: Research Article
ISSN: 1355-2546

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