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FLIGHT experience during recent years with roller strip maps driven from Doppler groundspeed data in an ‘along’ and ‘across’ track mode has demonstrated many of the undoubted advantages of a pictorial display of ground position.

The purpose of this paper is to present a most accurate analytical model suit for the prediction of the elastic displacements in a ceramic strip for sensing longitudinal deformations. Accordingly, the objective of the analysis given is to develop a physically meaningful and simple‐as‐possible stress‐strain model for an elongated strip attached to a thick‐and‐stiff substrate.

Today's advanced strain gage designs intended for measuring deformations and related physical characteristics use sensitive elements manufactured as ceramic strips. The output signal depends to a great extent on the ability to measure and to adequately interpret the induced elastic displacements in the strip, as the global electric resistor is coupled strongly to the strain field in the sensitive layer. The dependence of the strain on the thickness of a strip is calculated using an analytical 2D stress‐strain model using a shear tension applied at its interface with the substrate and zero‐stress at the opposite face as boundary conditions. All necessary considerations and calculations to develop the model are discussed.

A significant result is the gradual reduction in the deformation depending on the layer thickness. Applying the model combines easy numerical effort with an expressive approximation.

The developed model can be used in the analysis and physical design of the structural elements of the type in question, not necessarily in the field of strain gage and sensor engineering.

The purpose of this paper is to investigate the three-dimensional mixed convection flow of viscoelastic nanofluid induced by an exponentially stretching surface.

Similarity transformations are utilized to reduce the partial differential equations into the ordinary differential equations. The corresponding non-linear problems are solved by homotopy analysis method.

The authors found that an increase in thermophoresis and Brownian motion parameter enhance the temperature. Here thermal conductivity of fluid is enhanced due to which higher temperature and thicker thermal boundary layer thickness is obtained.

Heat and mass transfer effects in mixed convection flow over a stretching surface have numerous applications in the polymer technology and metallurgy. Such flows are encountered in metallurgical processes which involve the cooling of continuous strips or filaments by drawing them through a quiescent fluid and that in the process of drawing, these strips are sometimes stretched.

Three-dimensional flows over an exponentially stretching surface are very rare in the literature. Three-dimensional flow of viscoelastic nanofluid due to an exponentially stretching surface is first time investigated.

THE manufacturing methods and processes being used by Percival Aircraft Ltd., at Luton, in the production of the Prentice are of more than usual interest because this is the first metal aeroplane to be made by a firm well known for its wooden aircraft. Not only has the company built many hundreds of Gulls, Proctors and other wooden aeroplanes of its own design, but during the war the factory was largely occupied making Oxfords and Mosquitos. It is only in the post‐war period that Percival's have turned to metal, with the Prentice for the R.A.F. and the Merganser and Prince for the civil market. It was decided to design and build much of the works equipment. Examples of this are to be found in the two stretching presses, the strip rolls and the strip slitter.

The purpose of this paper is to study the problem of two‐dimensional unsteady mixed convective flow a dusty fluid over a stretching sheet in the presence of thermal radiation and space‐dependent heat source/sink.

The equations governing the fluid flow and temperature fields for both the fluid and dust phases are reduced to coupled non‐linear ordinary differential equations by using a suitable set of similarity transformations. Numerical solutions of the resulting equations are obtained using the well known RKF45 method.

The numerical results are benchmarked with previously published studies and found to be in excellent agreement. Finally, the effects of the pertinent parameters which are of physical and engineering interest on the flow and heat transfer characteristics are presented graphically and in tabulated form.

The problem is relatively original as the dusty fluid works for this type of problem are lacking.

The purpose of this paper is to reinvestigate the problem of multiple similarity solutions of the two-dimensional magnetohydrodynamic boundary-layer flow of an incompressible, viscous and electrically conducting fluid past a stretching/shrinking permeable surface studied by Aly et al. (2007).

The transformed ordinary (similarity) differential equation was solved numerically using the function bvp4c from MATLAB. The relative tolerance was set to 10^(−10).

Dual solutions were found and a stability analysis was performed to show which solutions are stable and which are not stable. On the other hand, Aly et al. (2007) have shown that for each value of the power index and magnetic parameter in the range and for any specific values of the stretching/shrinking parameter and suction parameter the problem has only a solution.

The paper describes how multiple (dual) solutions for the flow reversals were obtained. The stability analysis has shown that the lower solution branches are unstable, while the upper solution branches are stable.

A least‐squares finite element analysis of viscous fluid flow together with a trajectory integration technique for tracers is formulated and provides a mechanism for investigating mixing. Tracer integration is carried out using an improved Heun predictor‐corrector. Results from our supporting numerical studies on the CRAY and Connection Machine (CM) closely resemble the patterns of mixing observed in experiments. A “box‐counting” scheme and other measures to characterize the level of mixing are developed and investigated. This measure is utilized in numerical experiments to determine an optimal forcing frequency for mixing by periodic boundary motion in a rectangular enclosure. Some details concerning the numerical schemes and vector‐parallel implementation are also included.

The basic parameters of screen printing are discussed, and an analytical model of the screen printing process is introduced. The ink roll in front of the squeegee is treated as a pump generating, close to the squeegee edge, high hydrostatic pressure which injects ink into the screen meshes. The shearing of the ink, the mechanics of screen snap‐off and the ink transfer taking place behind the squeegee are also analysed.

This paper aims to consider the influence of the temperature and of an external magnetic field on the steady oblique stagnation-point flow for a Boussinesquian nanofluid past a stretching or shrinking sheet.

The flow is reduced through similarity transformations to an ordinary boundary value problem, which is solved numerically in MATLAB using the bvp4c function. The behavior of the solution is discussed physically, and some analytical considerations concerning existence of the solution and the occurrence of dual solutions are drawn.

The study of the influence of an external magnetic field on the oblique stagnation-point flow of a Buongiorno's Boussinesquian nanofluid is carried out. The fluid clashes on a vertical stretching or shrinking sheet. Dual solutions appear for suitable values of the parameters.

The present results are new and original.

The purpose of this paper is to describe the results of investigations of parachute rescue systems (PRS) for light gyrocopters.

Although the investigations were conducted in both stages simultaneously, i.e. experimental mechanics approach and numerical simulations, the paper is focussed mainly on the experimental part of the work. To ensure the safety of experimental works (i.e. for both experimenters and bystanders), the authors applied unmanned, remotely controlled scale models of autogyro for the PRS testing in the air.

The critical problem for successful use of the PRS is that the rotation of the rotor blades must be stopped when the main parachute opens, otherwise the influence of the rotor on the improper opening process of the parachute may cause the whole PRS to become useless.

The existing regulations for the use of unmanned aircraft impose the limitation upon the organisation of in-flight tests of PRS, i.e. the maximum take-off mass of the tested gyrocopter models is limited, and a full-scale test needs the approval of European Aviation Safety Agency (EASA).

The research contributes to increasing the safety level for gyrocopter users. The authors elaborated the original PRS, which currently is in the process of patenting.

Originality of the work consists of both an innovative PRS, which has never been tested before, and the results of experimental investigations, which cover both ground tests carried on static or moving stands and in-flight testing.