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The purpose of this paper is to study the coupled fixed point problem and the coupled best proximity problem for single-valued and multi-valued contraction type operators defined on cyclic representations of the space. The approach is based on fixed point results for appropriate operators generated by the initial problems.

A finite‐element model for calculating the die temperature profile for a hot‐forging operation is presented. The workpiece is modelled as a thermo‐viscoplastic material, while the dies are considered undeformable. Heat transfer between the dies and the workpiece is modelled using an iteratively coupled, fixed‐point calculation of the temperature in each domain. Transfer of temperature boundary conditions across contact interfaces is performed for non‐coincident meshes, using a boundary integration point contact analysis. Two industrial‐type examples are presented. In the first example, the effectiveness of the transfer of the temperature boundary conditions for a non steady‐state forging process is evaluated and determined to be satisfactory. Then weakly‐ and strongly‐coupled temperature resolutions are compared. It was found that the strongly‐coupled resolution may be necessary in order to obtain reasonably accurate results. In the second example, the weakly‐coupled resolution is compared to a constant‐temperature die approach for a relatively slow forging process, which shows the influence of the die temperature on the flow of the material.

The authors prove the existence and uniqueness of fixed point of mappings satisfying Geraghty-type contractions in the setting of preordered modular G-metric spaces. The authors apply the results in solving nonlinear Volterra-Fredholm-type integral equations. The results extend generalize compliment and include several known results as special cases.

The results of this paper are theoretical and analytical in nature.

The authors prove the existence and uniqueness of fixed point of mappings satisfying Geraghty-type contractions in the setting of preordered modular G-metric spaces. apply the results in solving nonlinear Volterra-Fredholm-type integral equations. The results extend, generalize, compliment and include several known results as special cases.

The results are theoretical and analytical.

The results were applied to solving nonlinear integral equations.

The results has several social applications.

The results of this paper are new.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The purpose of this paper is to access performance of existing computational techniques to model strongly non‐linear coupled thermo‐electric problems.

A thermistor is studied as an example of a strongly non‐linear diffusion problem. The temperature field and the current flow in the device are mutually coupled via ohmic heating and very rapid variations of electric conductivity with temperature and applied electric field, which makes the problem an ideal test case for the computational techniques. The finite volume fully coupled and fractional steps (splitting) approaches on a fixed computational grid are compared with a fully coupled front‐fixing method. The algorithms' input parameters are verified by comparison with published experiments.

It was found that fully coupled methods are more effective for non‐linear diffusion problems. The front fixing provides additional improvements in terms of accuracy and computational cost.

This paper for the first time compares in detail advantages and implementation complications of each method being applied to the coupled thermo‐electric problems. Particular attention is paid to conservation properties of the algorithms and accurate solutions in the transition region with rapid changes in material properties.

AIRCRAFT of the type known under the Registered Trade Mark “Autogiio,” have means for controllably tilting the rotor axis in relation to the body in one or more substantially vertical planes about real or virtual pivot axes, any such pivot axis being located above the centre of gravity of the aircraft, below the point of intersection of the rotor axis with the projection of the line of resultant aerodynamic action of the rotor on a plane containing both the rotor axis and the shortest distance between the rotor axis and the pivot axis, and offset from the rotor axis in the direction of the aerodynamic reaction line. Figs. 2 and 5 show diagrammatically an aircraft having a body b, a rotor comprising blades r, r, connected by horizontal hinges a, a, to a rotor hub having an axis of rotation 0, 0. Lines 0–0, 1–1, 2–2, etc., represent the projections on the plane of the paper of the aerodynamic reaction lines corresponding to successively reduced angles of incidence of the rotor, line 0–0 representing the reaction line for an angle of incidence of 90 deg. corresponding to vertical descent, line 5–5 representing that corresponding to a small angle of incidence corresponding to maximum flight speed. These projection lines intersect at a focal point f1, the height of which above the hinges a, a depends upon the degree of separation thereof, this height being zero when the hinges a, a are coaxial and intersect the axis of rotation. The transverse axis about which the rotor may be tilted is shown at p2 and is disposed below the point f1 and forward of the axis of rotation 0, 0. In the limiting case where the hinges a, a are coaxial p2 may pass through the point of intersection of the hinges with the axis 0–0. Fig. 5 shows how the longitudinal pivot axis p5 for lateral tilting of the rotor is displaced from the axis of rotation 0–0 in the direction of the aerodynamic reaction line, i.e., in the direction of the re‐treating blade. The transverse pivot p2 for longitudinal rotor tilting is located rearwardly of the centre of gravity, the perpendicular from the centre of gravity on the pivot making an angle of the order of 6 deg. with the perpendicular to the longitudinal body axis. Means may also be provided for bodily displacing the rotor longitudinally of the aircraft whereby the attitude of the body to the line of flight may be controlled in the plane of symmetry, independently of the flying speed and of the position of the centre of gravity. In one embodiment, Fig. 6, a pyramid of struts 36 supports a rotor comprising blades 38 secured to a hub 37 by horizontal pivots 39, links 40, and vertical pivots 41. Hub 37 is mounted on an axis member 78, Figs. 9 and 10, pivotally mounted on pyramid 36 by means of a transverse pivot 42 and a longitudinal pivot 43, Fig. 8. Pyramid struts 36 are bolted to an apex member 71 incorporating a fork 72, Fig. 10, carrying transverse pivot 42 on which is rotatably mounted an intermediate member incorporating an offset backward projection constituting the longitudinal pivot 43 and a downward projection 76 which serves to limit rocking of member 74 about the pivot 42 by co‐operation with the sides of a shot 71x formed in apex member 71. Rocking movement of axis member 78 in pivot 43 is limited by integral lugs 80 which embrace the projection 76. Movements of part 74 about pivot 42 and of axis member 78 about pivot 43 are damped by spring‐loaded friction discs 148, 153 respectively, the pressure on which may be varied by adjusting their respective nuts 151, 156. As shown in Fig. 9, an internal expanding rotor brake and rotor starting gear are associated with the axis member 78, the latter gear including a dog clutch permitting over‐running of the rotor with respect to the drive shaft. Means for controlling the rotor tilting movements comprise levers 48, 52 respectively associated with the intermediate member 74 and the axis member 78. Lever 48 is coupled to a bell crank 46, Fig. 6, by a rod 47, and lever 52 is coupled to a lever 50, Fig. 8, on a longitudinal rock shaft 49 by rod 51, bell crank 46 and rock shaft 49 being operated by a conveniently arranged control column 44. Rods 47, 51 are tubular and are connected to their respective levers 48, 52 by resilient connections comprising columns of rubber rings 106, Fig. 9, which bear against abutments 107 fixed in the bore of the rod and against a collar 108 formed on a slidable rod 109 which is connected to the operating lever by a forked shackle 110, in the case of rod 47, and by a shackle 111 and an eyed swivel 112, Fig. 10, in the case of rod 51. Means are provided for imposing an elastic bias on either control: these comprise in the case of the fore‐and‐aft control two lengths 116 of shock absorber elastic, Fig. 11, coupled at one end to a lever 115 on shaft 113 of bell crank 46, and at the other by cables 117 to an adjustable lever 119 working in a quadrant 120. Similarly, shock absorbers 123 are coupled to a lever 122 on rock shaft 49 and are connected by cables 124, Fig. 12, passed round pulleys 126 to a lever 127 mounted on a subsidiary rock shaft 128, the angular position of which is controlled by a ratchet lever 129, Fig. 11. Shackles 118 are adjustable for varying the initial stress in elastics 116 and turnbuckles 125 are placed in the run of cables 124. In addition to control column 44, a rudder bar 55 is provided operating a rudder 54, Fig. 6, and a steerable tail wheel 64, and a lever 62 for adjusting a tail plane 57. All these controls may be locked in any adjusted position, lever 62 by a ratchet 63 and the remainder by means of friction clamps 141, 142, 143 respectively, Figs. 11 and 12. Clamp 141 locks a slotted lever 140 fast on rock shaft 49 to a fixed fuselage member. Similarly clamp 135 co‐operates with a slotted plate 134, linked by rod 133 to a lever, 132, on rock shaft 113. Clamp 143 co‐operates with a slotted plate 142, inserted in the run of a rudder cable 56x.

Underactuated fingers are adapted to generate several grasping modes for different tasks, and coupled fingers and self-adaptive fingers are two important types of them. Aiming to expand the application and increase adaptability of robotic hand, this paper aims to propose a novel grasping model, called coupled and indirectly self-adaptive (CISA) grasping model, which is the combination of coupled finger and indirectly self-adaptive finger.

CISA grasping process includes two stages: first, coupled and then indirectly self-adaptive grasping; thus, it is not only integrated with the good pinching ability of coupled finger but also characterized with the high flexibility of indirectly self-adaptive finger. Furthermore, a CISA hand with linkage-slider, called CISA-LS hand, is designed based on the CISA grasping model, consisting of 1 palm, 5 CISA-LS fingers and 14 degrees of freedom.

To research the grasping behavior of CISA-LS hand, kinematic analysis, dynamic analysis and force analysis of 2-joint CISA-LS finger are performed. Results of grasping experiments for different objects demonstrate the high reliability and stability of CISA-LS hand.

CISA fingers integrate two grasping modes, coupled grasping and indirectly self-adaptive grasping, into one finger. And a double-linkage-slider mechanism is designed as the switch device.

To propose an integrated algorithm for aerodynamic shape optimization of aircraft wings under the effect of aeroelastic deformations at supersonic regime.

A methodology is proposed in which a high‐fidelity aeroelastic analyser and an aerodynamic optimizer are loosely coupled. The shape optimizer is based on a “CAD‐free” approach and an exact gradient method with a single adjoint state. The global iterative process yields optimal shapes in the at‐rest condition (i.e. with the aeroelastic deformations substracted).

The methodology was tested under different conditions, taking into account a combined optimization goal: to reduce the sonic boom production, while preserving the aerodynamic performances of flexible wings. The objective function model contains both aerodynamic parameters and an acoustic term based on the sonic boom downwards emission.

This paper proposes a shape optimization methodology developed by researchers but aiming at the final strategic goal of creating tools that can be really integrated in design processes.

The paper presents an original loosely coupled method for the shape optimization of flexible wings in which recent and modern techniques are used at different levels of the global algorithm: the aerodynamic optimizer, the aeroelastic analyser, the shape parametrization and the objective function model.

This paper aims to discuss the dynamic adsorption processes of carbon dioxide in a porous fixed bed on the industrial scale, using a multiple-relaxation-time lattice Boltzmann (LB) model.

A multiple-relaxation-time LB model is developed to predict the dynamic adsorption processes of carbon dioxide in a porous fixed bed on the industrial scale. The breakthrough curves from the simulation results are compared with the experimental data to validate the reliability of this model, and the effects of flow velocity, porosity and linear driving force mass transfer coefficient on the adsorption behaviors of carbon dioxide are explored further.

The numerical results show that the improved fluid flux leads to the reduction in the time required for completion of adsorption processes nonlinearly, and the differential pressure significantly raises with the decreasing porosity of porous fixed bed for fixed values of Reynolds number and total adsorption capacity. The maximum adsorption ratio of carbon dioxide was found at Re = 12 in this work. In addition, the higher mass transfer resistance of adsorbent particles advances the appearance time of the breakthrough point and delays the completion time of the adsorption processes.

This work will provide a way to study the adsorption technology of carbon dioxide in the fixed-bed using the LB method.

Drawing on literature that examines trade union representation of “non‐standard” workers, this paper aims to analyse the attempts of the Association of University Teachers (AUT) to integrate the interests of contract research staff (CRS) employed on fixed‐term contracts between 1974 and 2002. The paper examines the union campaign under five areas identified in the literature as important to the development of representation of non‐standard workers: trade union orientation to non‐standard workers; recruitment; participation; collective bargaining; extending representation beyond collective bargaining.

The main sources of data are drawn from analyses of union documentation, including internal memoranda and reports dating back to 1974, which chart the antecedents and progress of the AUT campaign against casualisation. This is supported by participant and non‐participant observation of 14 union meetings and events coupled with data from 20 semi‐structured interviews with a range of national officers and local activists conducted between 1999 and 2002.

The data support previous research that has identified changing union orientations to non‐standard workers. In the AUT, recruitment of CRS was propelled by instrumental needs to build and extend a declining membership base, but active participation of members employed on fixed‐term contracts has influenced union democracy and the collective bargaining agenda. However, the results, in terms of concrete gains in job security for CRS, have been limited.

The paper examines a case study of one union in particular circumstances. Although the findings add to the general knowledge of union representation on non‐standard workers, the outcomes are specific to the case study union. The paper concludes with an evaluation of the effectiveness of the AUT campaign against casualisation whilst highlighting the implications for the development of conceptual and theoretical frameworks on the representation of “non‐standard” workers.

The paper provides unique and detailed historical data on one trade union's attempts to integrate the interests of academics employed on fixed‐term contracts into union structures originally designed to service one of the most secure sectors of the British workforce.