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THE biplane wings are braced in two bays, the top and bottom planes being of equal span and chord. The inner bays consist of a wide centre‐section system, the engine mountings being situated in the plane of the inner gap struts which are fitted at the centre‐section extremities. The top centre section is mounted above the fuselage on four steel tubular struts attached to fittings at the top corners of the rectangular section fuselage, the rear pair forming an inverted vee and the front pair a slightly wider angle. Streamline wire cross‐bracing is fitted between the front pair of struts and drag bracing between the two pairs. The bottom centre section, which consists of two separate units, is attached directly to the fuselage at the bottom corners and supported by sloping struts in the front bay only from the top fuselage fittings to their extremities. Double flying wires are used in the front bay and single cross‐bracing wires in the rear bay. The outer bays are braced normally as regards flying, landing and incidence bracing by single streamline wires. Frise type ailerons are fitted to top and bottom planes and connected on each side by inter‐aileron struts.

The purpose of this paper is to simulate and analyze the excitation and propagation of surface plasmon polaritons (SPPs) on sinusoidal metallic gratings in conical mounting.

Chandezon's method has been implemented in MATLAB environment in order to compute the optical response of metallic gratings illuminated under azimuthal rotation. The code allows describing the full optical features both in far- and near-field terms, and the performed analyses highlight the fundamental role of incident polarization on SPP excitation in the conical configuration.

Results of far-field polarization conversion and plasmonic near-field computation clearly show that azimuthally rotated metallic gratings can support propagating surface plasmon with generic polarization.

The recent papers experimentally demonstrated the benefits in sensitivity and the polarization phenomenology that are originated by an azimuthal rotation of the grating. In this work, numerical simulations confirm these experimental results and complete the analysis with a study of the excited SPP near-field on the metal surface.

This paper investigates new technological devices to be utilised in future optical communications, by means of variational method (FEM) and multipole scattering approach (Rayleigh method). This last one provides interesting asymptotic results in the long‐wavelength limit. The so‐called photonic crystal fibres (PCF) possess radically different guiding properties due to photonic band gap guidance: removing a hole within a macro‐cell leads to a defect state within the gap. In the case of multi‐core PCF, the localised modes start talking to each other which possibly leads to a new generation of multiplexer/demultiplexers.

Sectional warping is the most widely used warp preparation process in weaving. Winding all warp sections with the same length and same tension is a key factor for a good quality warp preparation. It is required that winding thickness (increase in radius due to warp winding) remains the same within and between warp sections. The purpose of this paper is to investigate winding thickness variations within and between warp sections, which can lead to quality problems in woven fabrics.

A measurement system is developed and then an experimental investigation into winding thickness variations is carried out. Winding thickness is measured with respect to number of drum revolutions using a laser sensor with 20 microns resolution. The number of drum revolutions and drum angular position are measured by an incremental encoder. Both sensors are mounted on an industrial sectional warping machine. A real-time software written in C programming language collects and records the data for all sections of warp with respect to drum number of revolutions and then results are evaluated to determine winding thickness variations.

Results show that warp sheet thickness starts with a higher value and it decreases up to around 30 drum revolutions and then it remains constant or decreases very slightly which can be considered as insignificant from practical point of view. Warp sheet thickness (i.e. thickness of one warp layer) fluctuates within each section up to 10 percent CV with five drum revolutions average warp sheet thickness. There are also warp sheet thickness variations between warp sections up to 3 mm.

Considering the short of practical research results on winding thickness variations in the literature, results of this study will be an original contribution to understanding winding thickness variation level. Also, results presented in this paper can be used to develop control algorithms for thickness control in sectional warping machines.

The purpose of this paper is to propose an innovative method to extend the operating range of the laser tracking system and improve the accuracy and automation of boresighting by designing a measurement instrument. Boresighting is a process that aligns the direction of special equipment with the aircraft reference axis. Sometimes the accurate measurement and adjustment of the equipment and the aircraft are hard to achieve.

The aircraft is moved by an automatic adjustment system which consists of three numerical control positioners. For obtaining the position of the bore axis, an instrument with two measurement points is designed. Based on the multivariate normal distribution hypothesis, an uncertainty evaluation method for the aiming points is introduced. The accuracy of the measurement point is described by an uncertainty ellipsoid. A compensation and calibration method is proposed to decrease the effect of manufacturing error and deflection error by the finite element analysis.

The experimental results of the boresighting measurement prove that the proposed method is effective and reliable in digital assembly. The measurement accuracy of the angle between the bore axis and the reference axis is about ±0.004°. In addition, the measurement result is mainly influenced by the position error of the instrument.

The results of this study will provide a new way to obtain and control the installation deviation of part in aircraft digital assembly and will help to improve the precision and efficiency. This measurement method can be applied to obtain the axis of a deep blind hole.

The purpose of this paper is to investigate of the ultra‐wide band (UWB) characteristics of a conical antenna covered by an electromagnetic band‐gap (EBG) structure composed of alternating high‐ and low‐permittivity dielectric spherical shells.

A finite difference time domain in spherical coordinates is implemented in order to characterize the antenna's performance and waveform fidelity in case an UWB pulse is used. The method of projected effective permittivity is used in order to treat accurately the dielectric interfaces between the dissimilar spherical shells.

The design achieves a very wide impedance bandwidth above 5.5 GHz and presents UWB radiation characteristics and high average gain over the whole bandwidth. The radiation patterns are monopole‐like and their frequency dependence is small in the whole UWB frequency band. A time domain study has shown that the antenna distorts the excitation pulse in a moderate way.

In this paper, a quasi‐planar wideband conical antenna coated on a dielectric EBG structure is proposed for what is believed to be the first time. It is mechanically stable and, relatively easy to build and integrate with the planar circuits.

THE Wolseley A.R.9 engine is a nine‐cylinder air‐cooled radial rated at 185 h.p.

Bristol Mercury Engines The Bristol Aircraft Company announce the putting into production of their new series of “Mercury” engines. Although the new engines are of the same nine‐cylinder air‐cooled radial types as the Jupiter “F” the introduction of up‐to‐date features has necessitated entire re‐designing, and the new Mercury will therefore be produced side by side with the Jupiter, the two being non‐interchangeable.

A description of how oxygen pressure vessels for the prototype B.A.C./Sud Concorde are manufactured from seamless steel tubing produced by the Weldless works of Tubes Limited and an outline of the salient features of the Concorde's oxygen system for crew and passengers. On February 28, 1968—just fourteen months hence—the first prototype Concorde supersonic airliner (FIG. 1) will make its maiden flight from the Toulouse‐Blagnac airfield in France. Six months later the second prototype will make its first flight from British Aircraft Corporation's airfield at Filton, Bristol. In September 1969, and November 1969, respectively, two pre‐production aircraft will fly for the first time—these having a longer fuselage, higher gross weight, additional fuel capacity and higher payload capacity than the prototype aircraft. Apart from the fact that the pre‐production types will carry full flight test instrumentation, they will be fully representative of production Concordes—60 of which have already been ordered for service with thirteen leading world airlines.

There is no doubt that there is a need for new traditions, that is, wisdoms for enhanced responsible business in Africa. As one of the oldest world economies, Africa has a rich history of responsible indigenous business traditions that have sustained and supported her people’s principled business entrepreneurship over the centuries. However, there is little knowledge about these African responsible indigenous business traditions in the international literature. Currently, internationally familiar Western responsible business traditions dominate global responsible management knowledge and practice. The chapter explores responsible indigenous business traditions amongst the Sesotho-speaking people of Southern Africa called Basotho, bringing to light an aspect of responsible indigenous business management knowledge and practice from Southern Africa. These Basotho’s responsible indigenous business traditions embedded in Mokorotlo business model are Seahlolo, that is, communal, or mutual aid sharing, Letsema, that is, communal work party, Tsimo-ea-lira, that is, the field of enemies, Moelela, that is, food paid for work at threshing time, and Mafisa, that is, communal livestock loaning. The chapter concludes by suggesting that these Mokorotlo business traditions are prima facie attractive to be taken seriously in the global responsible management knowledge and practice.