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Article
Publication date: 1 February 2000

A. Ziadi and Y. Cherruault

The reducing transformation and global optimization technique called Alienor has been developed in the 1980s by Cherruault and Guillez. These methods are based on the…

Abstract

The reducing transformation and global optimization technique called Alienor has been developed in the 1980s by Cherruault and Guillez. These methods are based on the approximating properties of α ‐dense curves. The aim of this work is to give a very large class of functions generating α ‐dense curves in a hyper‐rectangle of Rn.

Details

Kybernetes, vol. 29 no. 1
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 July 1959

D.E. Clippinger and G.J. Morris

THE use of liquid oxygen as an oxidizer for various fuels in liquid rocket propellent systems is not new. Professor Goddard used liquid oxygen in his rocket experiments and the…

Abstract

THE use of liquid oxygen as an oxidizer for various fuels in liquid rocket propellent systems is not new. Professor Goddard used liquid oxygen in his rocket experiments and the well known German V‐2 rockets used this material as an oxidizer. However, its effect on non‐metallic materials ordinarily used in rocket systems was not investigated until recent years. This investigation was prompted by phenomena which had been experienced by rocket engine and rocket aircraft manufacturers and by suppliers of the material. It was observed that when some organic materials came in intimate contact with liquid oxygen they became prone to detonation when subjected to certain impact energies. This was undoubtedly due to the formation of unstable organo‐peroxide compounds which when impacted released high levels of energy resulting in an explosion. Specifically, when liquid oxygen was accidently spilled on asphalt and inadvertently stepped on, the asphalt would often explode. Also, leather gaskets immersed in liquid oxygen and subjected to surge impact detonated with disastrous effects.

Details

Aircraft Engineering and Aerospace Technology, vol. 31 no. 7
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 April 1973

ELDO C. KOENIG

Artificial automata replace, in part or in total, natural automata in systems, and properly disciplined models of natural automata become design models of artificial automata for…

Abstract

Artificial automata replace, in part or in total, natural automata in systems, and properly disciplined models of natural automata become design models of artificial automata for replacement. In Part I, a summary of two sets of disciplines provided by a General Systems Theory is presented, and the importance of these disciplines to the modeling of three inherited abilities is indicated for a case study. A theorem is presented in the form of an algorithm to aid in the modeling of the ability to modify and extend knowledge structures. In Part II (appearing in the next issue), the proof of the theorem is given and the theorem is applied to the case study. Finally, the application of the disciplines of the General Systems Theory is indicated for a second casestudy of an industrial system of 10 interactive automata.

Details

Kybernetes, vol. 2 no. 4
Type: Research Article
ISSN: 0368-492X

Article
Publication date: 1 December 2003

Miguel Lloret‐Climent

In systems theory, authors such as Klir, Miller, Yang, Lin and Ma, Backlund, etc. have developed different definitions of the system concept in function of both the type of…

Abstract

In systems theory, authors such as Klir, Miller, Yang, Lin and Ma, Backlund, etc. have developed different definitions of the system concept in function of both the type of variables used and the type of connection between variables. The concept of the subsystem, however, tends not to vary substantially from author to author, and this leads to a new system definition based on the subsystem concept, analysing the possible cases of interaction between subsystems and obtaining results for the overall system from an analysis of its subsystems.

Details

Kybernetes, vol. 32 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 30 March 2012

Ailixier Aikebaier, Makoto Takizawa, Isamu Tsuneizumi, Makoto Ikeda and Tomoya Enokido

A group of n (> 1) peers are required to cooperate with each other in distributed applications on P2P overlay networks. A P2P group is distributed without a centralized controller…

Abstract

Purpose

A group of n (> 1) peers are required to cooperate with each other in distributed applications on P2P overlay networks. A P2P group is distributed without a centralized controller and is scalable and heterogeneous. The purpose of this paper is to discuss how to realize a scalable group in P2P overlay networks.

Design/methodology/approach

In a group, messages have to be causally delivered to every peer. In order to realize a scalable group, messages are ordered by taking advantage of linear time (LT) and physical time (PT) since message length is O(1). Here, each peer has to hold information on the accuracy of physical clock of each peer and minimum delay time among every pair of peers. Since the size of the information is O(n2), it is difficult for each peer to hold the information and so the authors discuss a multi‐layered model to reduce the size of group information.

Findings

Through the evaluation studies, it is shown how the size of the group information can be reduced in a multi‐layered group compared with a traditional flat group.

Originality/value

In this paper, the authors discuss a multi‐layered group model for a scalable group, to reduce the size of group information; and also order messages by using both the linear time and physical time.

Details

International Journal of Pervasive Computing and Communications, vol. 8 no. 1
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 1 February 1995

Esteban, J.A. Pardo, M.C. Pardo and M.L. Vicente

Several coefficients, called divergences, have been suggested in the statistical literature to reflect the fact that some probability distributions are “closer together” than…

537

Abstract

Several coefficients, called divergences, have been suggested in the statistical literature to reflect the fact that some probability distributions are “closer together” than others and consequently that it may be easier to distinguish between the distributions of one pair than between those of another. When comparing three biological populations, it is often interesting to measure how two of them “move apart” from the third. Deals with the statistical analysis of this problem by means of bivariate divergence statistics. Provides a unified study, depicting the behaviour and relative merits of traditional divergences, by using the (h,ø), divergence family of statistics introduced by Menéndez et al.

Details

Kybernetes, vol. 24 no. 1
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 March 2002

Guoyang Liu

In this paper, we introduce the concept of a supporting set for a general system. We study basic properties of supporting sets for a general system, supporting sets for subsytems…

Abstract

In this paper, we introduce the concept of a supporting set for a general system. We study basic properties of supporting sets for a general system, supporting sets for subsytems of a system, homomorphic images of supporting sets for a system, and supporting sets for free sums and direct sums of systems.

Details

Kybernetes, vol. 31 no. 2
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 February 2004

Y. Long and D. Boren

Based on the definitions of poor data, an unascertained model and four axioms, condition functions and range etc. were analyzed then induced second‐order condition function…

136

Abstract

Based on the definitions of poor data, an unascertained model and four axioms, condition functions and range etc. were analyzed then induced second‐order condition function, complemental condition function, connection function and the rule set of some signs concludes with the forecast method, which consists of four theorems and ten inferences, in the condition of data number m (m≥2) in Rn.

Details

Kybernetes, vol. 33 no. 2
Type: Research Article
ISSN: 0368-492X

Keywords

Open Access
Article
Publication date: 31 December 2021

Rishabh Ranjan, P.N. Pandey and Ajit Paul

In this paper, the authors prove that the Douglas space of second kind with a generalised form of special (α, β)-metric F, is conformally invariant.

Abstract

Purpose

In this paper, the authors prove that the Douglas space of second kind with a generalised form of special (α, β)-metric F, is conformally invariant.

Design/methodology/approach

For, the authors have used the notion of conformal transformation and Douglas space.

Findings

The authors found some results to show that the Douglas space of second kind with certain (α, β)-metrics such as Randers metric, first approximate Matsumoto metric along with some special (α, β)-metrics, is invariant under a conformal change.

Originality/value

The authors introduced Douglas space of second kind and established conditions under which it can be transformed to a Douglas space of second kind.

Details

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

Keywords

Article
Publication date: 19 June 2007

Y. Villacampa, F. Verdú and A. Pérez

The purpose of this paper is to carry out a theoretical study of the stability of the mathematical models defined in a class of systems. Furthermore, it will be supposed that the…

Abstract

Purpose

The purpose of this paper is to carry out a theoretical study of the stability of the mathematical models defined in a class of systems. Furthermore, it will be supposed that the models have been obtained from experimental data and by means of the application of a methodology. The studies carried out in this paper are, on one hand, the theoretical framework for an analysis of the sensitivity and stability of a type of systems; on the other hand, they supplement the studies carried out by the authors, in which, using a computational program, the sensitivity of the mathematical models is analyzed with respect to a type of perturbation.

Design/methodology/approach

Initially, a class of systems is considered that are denominated quantifiable systems, in which model systems are defined that are determined by a set and a family of relationships. An initial study of the sensitivity of the mathematical models to perturbations in the experimental data lead to a concept of sensitive and stable models that forms the basis of the theory of stability developed in this paper. Furthermore, this permits a definition of the stability function for the set of the perturbations and, consequently, a determination of stable models according to the defined theoretical structure.

Findings

An analysis of the sensitivity and stability of mathematical models in quantifiable systems from a systems theory perspective will be fundamental for the determination of mathematical model stability in environmental systems.

Originality/value

The studies carried out in this paper supposes an advance in the study and modeling of a type of systems that the authors have denominated as quantifiable systems, applicable to the study of environmental systems and supplementing the numeric studies carried out by the authors.

Details

Kybernetes, vol. 36 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

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