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The object of this paper is to describe English Electric work and experience in the development and application of computer‐produced indexes.

The loans control system used at AWRE is described in detail. Punched cards produced in the library are used as input to a computer to provide the necessary control tools: reminders, borrower, and date listings. Details are given of a method of using the computer to perform a sort in UDC number order. Plans to integrate and mechanize the cataloguing and ordering operations using an IBM 870 system and an IBM 360/30 computer are also described.

Published experiences dealing with the use of data processing equipment in conjunction with classification systems, particularly the UDC, are reviewed. Earlier conclusions, generalized from experience with punched card equipment, were too pessimistic. Difficulties in handling UDC notation in computer systems and methods for overcoming them are discussed. Ways in which computers can aid in studying, improving, and using classification systems are discussed. Experience at Meteorological and Geoastrophysical Abstracts is cited.

A description is given of the English Electric ‘Thesaurofacet’, a faceted classification and thesaurus covering engineering and related scientific, technical, and management subjects. A novel feature of the system is the integration of the classification schedules and thesaurus. Each term appears both in the thesaurus and in the schedules. In the schedules the term is displayed in the most appropriate facet and hierarchy: the thesaurus supplements this information by indicating alternative hierarchies and other relationships which cut across the classified arrangement. The thesaurus also controls word forms and synonyms and acts as the alphabetical index to the class numbers. The resulting tool is multipurpose, as easily applicable to shelf arrangement and conventional classified card catalogues as to co‐ordinate indexing and computerized retrieval systems. The reasons are given for modifying certain traditional facet techniques, including the choice of traditional disciplines for main classes, the lack of a ‘built‐in’ preferred order, and the me, in certain instances, of enumeration rather than synthesis to express multi‐term concepts. Methods of application of the Thesaurofacet in pre‐coordinate and post‐coordinate systems are discussed and a brief account is given of the techniques employed in its compilation.

The purpose of this paper is to investigate the effect of the interlocking process on the iron loss in the lamination core and to increase the efficiency of electrical machines.

A 3D electromagnetic model of the interlocking dowels is proposed in order to simulate the eddy current distribution in the lamination core. Considering the time-consuming of the 3D finite element method (FEM), a 2D electromagnetic model is then proposed based on the 3D model. Influence of the interlocking process on the motor performances is analyzed with 2D FEM, considering the electrical connection of the dowels and the magnetic property deterioration of the electrical steel sheets.

The interlocking process removes the insulation between the laminations at the cut-edges of the interlocking dowels, causing extra eddy current loss in the lamination core. The effect of the interlocking process is dependent on the number, location and size of the interlocking dowels.

The interlocking dowel model is established in order to simulate the effects of the interlocking process. By using the FEM calculation, optimal solution is discussed to minimize the undesired effect of the interlocking dowels.

In this paper, the FEM model of the induction motor with interlocked stator core is first established, then simulation analysis is implemented. Results shows that choosing a proper number of interlocking dowels with suitable location and size can reduce the extra loss.

This chapter describes how conversational computer agents have been used in collaborative problem-solving environments. These agent-based systems are designed to (a) assess the students’ knowledge, skills, actions, and various other psychological states on the basis of the students’ actions and the conversational interactions, (b) generate discourse moves that are sensitive to the psychological states and the problem states, and (c) advance a solution to the problem. We describe how this was accomplished in the Programme for International Student Assessment (PISA) for Collaborative Problem Solving (CPS) in 2015. In the PISA CPS 2015 assessment, a single human test taker (15-year-old student) interacts with one, two, or three agents that stage a series of assessment episodes. This chapter proposes that this PISA framework could be extended to accommodate more open-ended natural language interaction for those languages that have developed technologies for automated computational linguistics and discourse. Two examples support this suggestion, with associated relevant empirical support. First, there is AutoTutor, an agent that collaboratively helps the student answer difficult questions and solve problems. Second, there is CPS in the context of a multi-party simulation called Land Science in which the system tracks progress and knowledge states of small groups of 3–4 students. Human mentors or computer agents prompt them to perform actions and exchange open-ended chat in a collaborative learning and problem-solving environment.

The purpose of this paper is to develop the understanding of how external loads are reacted through preloaded bolted joints and the interaction of the joint elements. The paper develops ideas from how to do an analysis to understanding the implications of the results.

Classical methods of analysis are applied to preloaded bolted joints, made with multiple bolts. The paper considers both the detailed analysis of bolts stresses, fatigue analysis and load-based design analysis, to demonstrate the structural integrity of preloaded bolted joints.

In preloaded joints the external tensile axial load and moments are mainly supported by changes in contact pressure at the faying surface. Only a small proportion of the external loads produce changes in bolt tensile stress. The bolts have a significant mean stress but experience a low working stress range. This low stress range is a factor in explaning why preloaded bolted joints have good fatigue performance.

In many cases the methods presented are adequate to demonstrate the structural integrity of joints. In some cases finite element methods may be more appropriate, and the methods discussed can be used in the validation process.

The paper brings together a number of concepts and links them into a practical design analysis process for preloaded bolted joints. Interpretation of results, within the context of design standards, is provided.

Purpose – The purpose of this paper is to develop a framework which sheds new light on how sustainability control systems (SCS) can be used in proactive strategic responses to corporate sustainability pressures.

Design/Methodology/Approach – Corporate sustainability pressures are identified using insights from institutional theory and the resource-based view of the firm.

Findings – The paper presents an integrated framework showing the corporate sustainability pressures, proactive strategic responses to these pressures, and how organizations might use SCS in their responses to the corporate sustainability pressures they face.

Practical Implications – The proposed framework shows how organizations can use SCS in proactive strategic responses to corporate sustainability pressures.

Originality/Value – The paper suggests that instead of using traditional financial-oriented management control systems, organizations need more focus on emerging SCS as a means of achieving sustainability objectives. In particular, the paper proposes different SCS tools that can be used in proactive strategic responses to sustainability pressures in terms of (i) specifying and communicating sustainability objectives, (ii) monitoring sustainability performance, and (iii) providing motivation by linking sustainability rewards to performance.

The purpose of this paper is to devise an analytical approach to calculate conductor winding losses, considering multiple contributing aspects simultaneously. These include the geometric configuration of coil windings, frequency of the electric current and the dependency on the coil temperature, derived studying a coupled fluid–solid model considering the cooling system characteristics. The obtained results allow identifying power loss trends according to such system variables as coolant inlet temperature or overall flow rate of the motor.

An easy-to-use coupled analytical approach is applied, which is suitable for rapid estimations of the impact of parameter variation on the resulting conductor winding power losses that facilitates decision-making in the design process of electric aircraft engines.

In the considered cooling parameters, the overall conductor winding power losses vary approximately between 6 kW and 7.2 kW. More than 95 per cent of this loss is because of direct current losses. These losses cause the variation in maximal coil temperature ranging between 115°C and 170°C.

The SP260D motor is set and was currently tested in Extra 330. It recently broke two world records.

One of the current trends in aircraft engineering is electric aircraft. Advantages of electric aircraft include improved manoeuvrability because of greater torque from electric motors, increased safety because of decreased chance of mechanical failure, less risk of explosion or fire in the event of a collision and less noise. There will be environmental and cost benefits associated with the elimination of dependency on fossil fuels and resultant emissions.

The use of a novel fluid–solid interaction model for predicting conductor winding power loss of the SP260D electric aircraft motor has not been done earlier. A novel alternative derivation of the widely applied Dowell’s formula (Dowell, 1966) is presented for the estimation of proximity losses in square winding conductors.

This paper presents the full range sensitivity study of various components of material model on the response of reinforced concrete slabs subjected to central patch loads using non‐linear finite element analysis. A layered degenerate quadratic plate element with five degrees of freedom was employed. Smeared crack model was used with orthogonal cracking. The components considered in this work are: perfectly plastic models versus hardening models, role of crushing condition on collapse load, influence of dowel effect on punching capacity, parametric variation of tension stiffening parameter, parametric variation of degraded shear modulus and the role of yield criterion.