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Article
Publication date: 1 February 1943

F.E. Burger

THE aim of this paper is to provide a survey of some of the principal theoretical considerations affecting the design of aircraft undercarriages.

Abstract

THE aim of this paper is to provide a survey of some of the principal theoretical considerations affecting the design of aircraft undercarriages.

Details

Aircraft Engineering and Aerospace Technology, vol. 15 no. 2
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 June 1941

F.E. Burger

THE purpose of this article is to describe a useful variable velocity‐ratio unit suitable for inclusion in flying‐control circuits of aeroplanes, and to provide sufficient…

Abstract

THE purpose of this article is to describe a useful variable velocity‐ratio unit suitable for inclusion in flying‐control circuits of aeroplanes, and to provide sufficient of a mathematical analysis to assist designers in the accurate production of such a device. Worked examples are included to illustrate the procedure, and draughtsmen should find these helpful and preferable to a trial and error method of layout on the drawing board.

Details

Aircraft Engineering and Aerospace Technology, vol. 13 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 July 1944

F.E. Burger

THE bearing described in this article may help to solve many problems peculiar to aircraft design, where deflections of large orders are experienced between one location…

Abstract

THE bearing described in this article may help to solve many problems peculiar to aircraft design, where deflections of large orders are experienced between one location and another.

Details

Aircraft Engineering and Aerospace Technology, vol. 16 no. 7
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 December 1949

F.E. Burger

IN a previous article (Ref. 1) the present author outlined some fundamental considerations of general practice. In the present paper the intention is, in effect, to take…

Abstract

IN a previous article (Ref. 1) the present author outlined some fundamental considerations of general practice. In the present paper the intention is, in effect, to take some pages from a designer's notebook and explain in detail the procedure by which the dynamic characteristics of a leg are determined. A description of one of the author's own designs will provide a suitable area of reference, and although certain of the geometrical calculations will apply rather specially to this, the remainder of the working will be quite general in its application. In particular, the orifice calculations—a vitally useful aspect which has not previously been treated in a practical fashion—have been compared with drop‐test results over a range of differing designs and sizes of shock‐absorber and show very good agreement with them; certainly good enough for a close initial approximation, and in the style of leg described here and in other simple fixed orifice designs, sufficiently accurate to allow of dispensing with dynamic tests provided that tyre and oleo relationships do not diverge too far from the conventional.

Details

Aircraft Engineering and Aerospace Technology, vol. 21 no. 12
Type: Research Article
ISSN: 0002-2667

Open Access
Book part
Publication date: 5 September 2019

Kylie Baldwin

Abstract

Details

Egg Freezing, Fertility and Reproductive Choice
Type: Book
ISBN: 978-1-78756-483-1

Article
Publication date: 1 March 1947

F.E. Burger

THE practice of mechanically sealing liquids and gases within machines has shown little tendency to undergo any fundamental change since the earliest days of the art, and…

Abstract

THE practice of mechanically sealing liquids and gases within machines has shown little tendency to undergo any fundamental change since the earliest days of the art, and apart from the semi‐sealing properties of the elementary labyrinth in which measurable clearances exist as between a rotating shaft and its housing, some variant of the common ‘soft packing’ is the standard method of providing the closest form of contact sealing. This type of seal seems to have been engendered by the concept that only substances having extreme deformability could provide the closest degree of conformity to a circular shaft, and the type is brought into play in many ways, from the simple kind of soft, semi‐elastic ring which is rammed into a housing and thus becomes, due to its transverse elasticity, to some extent preloaded on to its co‐acting shaft, to the more refined rubber ring with its lip held against the shaft through the medium of an encircling garter‐spring of steel.

Details

Aircraft Engineering and Aerospace Technology, vol. 19 no. 3
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 September 1950

C.H. Cumberland and G.S. Bowey

THE passenger seat in civil aircraft is an important piece of equipment. It is important, firstly because it is the one part of the aircraft with which the passenger is in…

Abstract

THE passenger seat in civil aircraft is an important piece of equipment. It is important, firstly because it is the one part of the aircraft with which the passenger is in intimate contact and, secondly, because of the bulk and multiplicity of installation in any aircraft, the aggregate weight constitutes a major portion of equipment weight.

Details

Aircraft Engineering and Aerospace Technology, vol. 22 no. 9
Type: Research Article
ISSN: 0002-2667

Open Access
Article
Publication date: 9 March 2015

Aristides Matopoulos, Ana Cristina Barros and J.G.A.J. (Jack) van der Vorst

The study aims to define a research agenda for creating resource-efficient supply chains (RESCs) by identifying and analysing their key characteristics as well as future…

13663

Abstract

Purpose

The study aims to define a research agenda for creating resource-efficient supply chains (RESCs) by identifying and analysing their key characteristics as well as future research opportunities.

Design/methodology/approach

We follow a systematic review method to analyse the literature and to understand RESC, taking a substantive theory approach. Our approach is grounded in a specific domain, the agri-food sector, because it is an intensive user of an extensive range of resources.

Findings

The review shows that works of literature has looked at the use of resources primarily from the environmental impact perspective. There is a need to explore whether or not and how logistics/supply chain decisions will affect the overall configuration of future food supply chains in an era of resource scarcity and depletion and what the trade-offs will be.

Research limitations/implications

The paper proposes an agenda for future research in the area of RESC. The framework proposed along with the key characteristics identified for RESC can be applied to other sectors.

Practical implications

Our research should facilitate further understanding of the implications and trade-offs of supply chain decisions taken on the use of resources by supply chain managers.

Originality/value

The paper explores the interaction between supply chains and natural resources and defines the key characteristics of RESC.

Details

Supply Chain Management: An International Journal, vol. 20 no. 2
Type: Research Article
ISSN: 1359-8546

Keywords

Article
Publication date: 4 March 2019

Davide Settembre Blundo, Anna Lucia Maramotti Politi, Alfonso Pedro Fernández del Hoyo and Fernando Enrique García Muiña

The purpose of this paper is to explore the application of a hermeneutic-based approach as innovative way to study the Cultural Heritage management in a mesoeconomic space.

Abstract

Purpose

The purpose of this paper is to explore the application of a hermeneutic-based approach as innovative way to study the Cultural Heritage management in a mesoeconomic space.

Design/methodology/approach

The paper builds a theoretical framework based on the analysis of relevant literature in the field of cultural economics, heritage economics and conservation and restoration techniques. Then, after having defined the conceptual hypothesis, a hermeneutical interpretative model is designed for the analysis of the processes of Cultural Heritage management with particular regard to the strategies of stakeholder engagement.

Findings

The research shows how the mesoeconomic space is that border area where it is possible to solve more easily the conflicts that arise as a result of the different expectations of stakeholders. Hermeneutical analysis, applied in iterative form, allows us to find common connections, points of contact and convergences between the interpretative horizons of the various stakeholders.

Practical implications

The application of the interpretative model allows the identification of the expectations of stakeholders, improving the knowledge of the tangible and intangible attributes of works of art, in order to design appropriate interventions of restoration, conservation and valorization.

Social implications

The new model of analysis, based on hermeneutic methodology, is designed to understand and describe the social and economic relations between the different stakeholders involved in the management of Cultural Heritage.

Originality/value

This paper examines for the first time the Cultural Heritage sector within the mesoeconomic area between the micro and the macroeconomy. In addition to this mesoeconomic analysis and conceptual approach, the authors introduce as methodology the economic hermeneutics that represents an innovative tool in the field of economic and business disciplines.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. 9 no. 3
Type: Research Article
ISSN: 2044-1266

Keywords

Article
Publication date: 9 April 2020

Ranjan Kumar Mohanty and Sachin Sharma

This paper aims to develop a new high accuracy numerical method based on off-step non-polynomial spline in tension approximations for the solution of Burgers-Fisher and…

Abstract

Purpose

This paper aims to develop a new high accuracy numerical method based on off-step non-polynomial spline in tension approximations for the solution of Burgers-Fisher and coupled nonlinear Burgers’ equations on a graded mesh. The spline method reported here is third order accurate in space and second order accurate in time. The proposed spline method involves only two off-step points and a central point on a graded mesh. The method is two-level implicit in nature and directly derived from the continuity condition of the first order space derivative of the non-polynomial tension spline function. The linear stability analysis of the proposed method has been examined and it is shown that the proposed two-level method is unconditionally stable for a linear model problem. The method is directly applicable to problems in polar systems. To demonstrate the strength and utility of the proposed method, the authors have solved the generalized Burgers-Huxley equation, generalized Burgers-Fisher equation, coupled Burgers-equations and parabolic equation in polar coordinates. The authors show that the proposed method enables us to obtain the high accurate solution for high Reynolds number.

Design/methodology/approach

In this method, the authors use only two-level in time-direction, and at each time-level, the authors use three grid points for the unknown function u(x,t) and two off-step points for the known variable x in spatial direction. The methodology followed in this paper is the construction of a non-polynomial spline function and using its continuity properties to obtain consistency condition, which is third order accurate on a graded mesh and fourth order accurate on a uniform mesh. From this consistency condition, the authors derive the proposed numerical method. The proposed method, when applied to a linear equation is shown to be unconditionally stable. To assess the validity and accuracy, the method is applied to solve several benchmark problems, and numerical results are provided to demonstrate the usefulness of the proposed method.

Findings

The paper provides a third order numerical scheme on a graded mesh and fourth order spline method on a uniform mesh obtained directly from the consistency condition. In earlier methods, consistency conditions were only second order accurate. This brings an edge over other past methods. Also, the method is directly applicable to physical problems involving singular coefficients. So no modification in the method is required at singular points. This saves CPU time and computational costs.

Research limitations/implications

There are no limitations. Obtaining a high accuracy spline method directly from the consistency condition is a new work. Also being an implicit method, this method is unconditionally stable.

Practical implications

Physical problems with singular and non-singular coefficients are directly solved by this method.

Originality/value

The paper develops a new method based on non-polynomial spline approximations of order two in time and three (four) in space, which is original and has lot of value because many benchmark problems of physical significance are solved in this method.

1 – 10 of over 3000