Search results

1 – 10 of over 73000
Content available
Article
Publication date: 22 May 2019

Adrian Magdaş

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…

Abstract

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.

To view the access options for this content please click here
Article
Publication date: 1 March 2006

A.J. Ostaszewski

To model a bargaining environment where the tactic of qualitative commitment (staking a principle) can have a demonstrably strong effect.

Abstract

Purpose

To model a bargaining environment where the tactic of qualitative commitment (staking a principle) can have a demonstrably strong effect.

Design/methodology/approach

Amend the two‐person alternating offers model due to Rubinstein to include simultaneously pre‐announced stakes, and a mechanism for altering agents' utilities by reference to substantial costs of “surrendering a principle” (capitulation costs). Identify all stationary, pure strategy equilibria. Isolate subgame perfect Nash equilibria (SPNE).

Findings

SPNE is unique and offers efficient re‐allocation. For high enough capitulation costs, gains at equilibrium (relative to the bench‐mark game without commitment) result to the first‐mover. The shift in the equilibrium allocation is linear in cost.

Research limitations/implications

Symmetric fixed capitulation costs were assumed. Surrender of principle required introduction of discontinuities in the cost function (zero or fixed cost). No gradation of the cost was considered. Future directions could involve discovering what distortions are created by asymmetric costs, by gradations and from smoothing out of the discontinuity.

Practical implications

Practical implications at best point to the potential rewards available from identifying and introducing a high‐cost commitment tactics in a bargaining context.

Originality/value

The innovation is in the use of an explicit bargaining apparatus to examine the commitment tactic (previous research used an axiomatic treatment of bargaining), and in offering a model for the notion of a qualitative commitment. The result about the qualitative shift in the equilibrium is also new. The paper is thus a contribution to the understanding of how an agent may seek to influence the outcome of a game such as “divide the pie (the resource)” through the manufacture/introduction of a factor outside the original game.

Details

Journal of Economic Studies, vol. 33 no. 2
Type: Research Article
ISSN: 0144-3585

Keywords

To view the access options for this content please click here
Article
Publication date: 19 October 2015

Mingyu Gao, Da Chen, Yuxiang Yang and Zhiwei He

The purpose of this paper is to propose a new trajectory planning algorithm for industrial robots, which can let the robots move through a desired spatial trajectory…

Abstract

Purpose

The purpose of this paper is to propose a new trajectory planning algorithm for industrial robots, which can let the robots move through a desired spatial trajectory, avoid colliding with other objects and achieve accurate movements. Trajectory planning algorithms are the soul of motion control of industrial robots. A predefined space trajectory can let the robot move through the desired spatial coordinates, avoid colliding with other objects and achieve accurate movements.

Design/methodology/approach

The mathematical expressions of the proposed algorithm are deduced. The speed control, position control and orientation control strategies are realized and verified with simulations, and then implemented on a six degrees of freedom (6-DOF) industrial robot platform.

Findings

A fixed-distance trajectory planning algorithm based on Cartesian coordinates was presented. The linear trajectory, circular trajectory, helical trajectory and parabolic trajectory in Cartesian coordinates were implemented on the 6-DOF industrial robot.

Originality/value

A simple and efficient algorithm is proposed. Enrich the kind of trajectory which the industrial robot can realize. In addition, the industrial robot can move more concisely, smoothly and precisely.

Details

Industrial Robot: An International Journal, vol. 42 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Content available
Article
Publication date: 5 January 2021

Sushanta Kumar Mohanta

In this paper, we use the notion of cyclic representation of a nonempty set with respect to a pair of mappings to obtain coincidence points and common fixed points for a…

Abstract

Purpose

In this paper, we use the notion of cyclic representation of a nonempty set with respect to a pair of mappings to obtain coincidence points and common fixed points for a pair of self-mappings satisfying some generalized contraction- type conditions involving a control function in partial metric spaces. Moreover, we provide some examples to analyze and illustrate our main results.

Design/methodology/approach

Theoretical method.

Findings

We establish some coincidence points and common fixed point results in partial metric spaces.

Originality/value

Results of this study are new and interesting.

Details

Arab Journal of Mathematical Sciences, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1319-5166

Keywords

To view the access options for this content please click here
Article
Publication date: 1 January 1991

In section II.1, “The Three Dimensions of Space”, it was argued that logical space comprised a “thought unit” of three dimensions, and it was then shown why natural space…

Abstract

In section II.1, “The Three Dimensions of Space”, it was argued that logical space comprised a “thought unit” of three dimensions, and it was then shown why natural space should consist of three dimensions as well. The attempt to provide a logically complete definition for the concept of time indicated that this too was to be viewed as a logical space of three dimensions. This raises the question of “how natural space and time are to be conceptually united in order to become intuitively perceptible from an operationist point of view”.

Details

International Journal of Social Economics, vol. 18 no. 1/2/3
Type: Research Article
ISSN: 0306-8293

To view the access options for this content please click here
Article
Publication date: 21 September 2020

Guangxin Wang, Lili Zhu and Peng Wang

The purpose of this paper is to obtain the single-tooth stiffness, single-tooth time-varying meshing stiffness and comprehensive meshing stiffness of the internal and…

Abstract

Purpose

The purpose of this paper is to obtain the single-tooth stiffness, single-tooth time-varying meshing stiffness and comprehensive meshing stiffness of the internal and external face gears and to analyze the influence of the modulus, pressure angle and tooth width of each face gear on the single-tooth stiffness of the gear in nutation face gear transmission.

Design/methodology/approach

From the point of view of material mechanics, the gear teeth of nutation face gear are simplified as spacial variable cross-section beams. The shear deformation of gear teeth, the bending deformation of tooth root and the additional elastic deformation caused by the base deformation are gotten by simplified trapezoidal section method, thus the stiffness of nutation face gear teeth can be obtained. The comparison with finite element method results verifies the rationality of simplified trapezoidal section method for calculating the tooth stiffness of nutation face gear.

Findings

The variation of stiffness of internal and external face gears along the meshing line and tooth height in nutation face gear transmission is studied, and the variation laws of single tooth stiffness, single-tooth-pair mesh stiffness and single tooth time-varying meshing stiffness of nutation face gear teeth are obtained.

Originality/value

Nutation face gear transmission is a new type of transmission. The stiffness of face gear teeth is analyzed, and the variation rules of single tooth stiffness, single-tooth-pair mesh stiffness and single tooth time-varying meshing stiffness of nutation face gear teeth are obtained, which not only enriches the research of nutation face gear transmission but also has important guiding significance for the application of nutation face gear in engineering practice.

Details

Engineering Computations, vol. 38 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article
Publication date: 1 January 2005

Louis H. Kauffman

Discusses the notion of eigenform as explicated by Heinz von Foerster wherein an object is seen to be a token for those behaviors that lend the object its apparent…

Abstract

Purpose

Discusses the notion of eigenform as explicated by Heinz von Foerster wherein an object is seen to be a token for those behaviors that lend the object its apparent stability in a changing world.

Design/methodology/approach

Describes von Foerster's model for eigenforms and recursions and puts this model in the context of mathematical recursions, fractals, set theory, logic, quantum mechanics, the lambda calculus of Church and Curry, and the categorical framework of fixed points of Lawvere.

Findings

Determines that iterating a transformation upon itself is seen to be a key to understanding the nature of objects and the relationship of an observer and the apparent world of the observer.

Originality/value

Contemplates the concept of recursion in the context of second‐order cybernetics.

Details

Kybernetes, vol. 34 no. 1/2
Type: Research Article
ISSN: 0368-492X

Keywords

Content available
Article
Publication date: 11 September 2007

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 5
Type: Research Article
ISSN: 0002-2667

To view the access options for this content please click here
Article
Publication date: 1 September 2020

Khaled Ahmed Mahmoud

In literature, previous studies have focused on analyzing rienforced concrete (RC) columns with idealized end conditions when subjected to fire. In nature, full fixity or…

Abstract

Purpose

In literature, previous studies have focused on analyzing rienforced concrete (RC) columns with idealized end conditions when subjected to fire. In nature, full fixity or free rotation at column ends is not attained. Such ends may be considered partially restrained in rotation. This paper aims to shed a new light on the effect of different degrees of rotational restraint on the lateral deformation behavior of slender heated RC columns subjected to non-linear strain distributions produced by a time-dependent temperature history.

Design/methodology/approach

To find the strain distribution on the cross section, an iterative technique is adopted using Newton–Raphson method. By introducing a reliable calculation procedure, the lateral deformational behavior is expressed using numerical and searching techniques. A methodology is presented to calculate the effective length factor for RC columns at elevated temperature.

Findings

The results of the proposed model showed good agreement with available experimental test results. It was also found that the variation of rotational end restraint level has a considerable effect on the lateral deformation behavior of heated slender RC columns. In addition, the effectiveness and the validity of an analytical model should be verified by simultaneously validating the axial and lateral deformations. Moreover, the effective length factor for heated column is higher than that for the corresponding column at ambient temperature.

Originality/value

This paper shows the impact of different boundary conditions on the behavior of heated slender RC columns. It suggests powerful techniques to determine the lateral deflection and the effective length factor at high temperatures.

Details

Journal of Structural Fire Engineering, vol. 12 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

To view the access options for this content please click here
Article
Publication date: 1 March 1975

M.A. KAAZ

Game‐theoretic studies1,2 have been extended and complemented by a coincidence theorem based on and closely related to the Lefschetz fixedpoint theory. It is shown…

Abstract

Game‐theoretic studies1,2 have been extended and complemented by a coincidence theorem based on and closely related to the Lefschetz fixedpoint theory. It is shown (Theorem 4) that admissible Hausdorff‐spaces (e.g. Banach spaces) exhibit coincidences of pairs of maps associated with multi‐valued maps which have been introduced and discussed in previous papers in this Journal.1,2

Details

Kybernetes, vol. 4 no. 3
Type: Research Article
ISSN: 0368-492X

1 – 10 of over 73000