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Article
Publication date: 19 August 2011

Yong Wei, Xin‐hai Kong and Da‐hong Hu

The purpose of this paper is to perfect the axiom systems of buffer operator via adding the axiom of invariable trend.

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Abstract

Purpose

The purpose of this paper is to perfect the axiom systems of buffer operator via adding the axiom of invariable trend.

Design/methodology/approach

Based on the three axioms of buffer operator, for any given data sequence of system behavior and any set of data satisfying the axiom of fixed point, it is proved that there always exists a buffer operator satisfying that the set of data is the buffer sequence of the given data sequence, and a specific constructor method of buffer operator is provided. Finally, the axiom of invariable trend is proposed to add in the axiom systems of buffer operator.

Findings

The results are convincing that although the raw sequence suffered from certain disturbance may be enlarged or reduced, the trend is in line with the original law. All predictions must be on the premise of this trend to forecast, or prediction will be considered invalid.

Practical implications

The method exposed in the paper can be used to construct a specific buffer operator between two sequences satisfying the axiom of fixed point.

Originality/value

The paper succeeds in providing a kind of universal constructor method for buffer operator, and adding the axiom of invariable trend to perfect the axiom systems of buffer operator and ensure the consistency of variation trend between the predicted values and the actual values.

Details

Grey Systems: Theory and Application, vol. 1 no. 2
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 5 February 2018

Tianxiang Yao and Hong Gao

Buffer operators can be utilized to improve the smooth degree of the raw data sequence, and to increase the simulation accuracy of the model. The purpose of this paper is to…

Abstract

Purpose

Buffer operators can be utilized to improve the smooth degree of the raw data sequence, and to increase the simulation accuracy of the model. The purpose of this paper is to analyze the cause of increase in the simulation accuracy of the buffer operator.

Design/methodology/approach

This paper probed into the modeling mechanism of several typical buffer operators such as the arithmetic buffer operators, the buffer operators with monotonic function and weighted buffer operators. The paper also gives an example of the buffer operator sequence.

Findings

The results indicate that after applying an infinite buffer operator, whether the authors adopt a weakening buffer operator or a strengthen buffer operator, the raw sequence can be changed into a constant sequence. Because the discrete GM(1,1) model can completely simulate constant sequence, the simulation accuracy is 100 percent. Because the discrete GM(1,1) model is the accurate form of the GM(1,1) model, after applying an infinite buffer operator, the GM(1,1) model can have a very high simulation accuracy. The buffer operator model can increase the simulation accuracy of both the GM(1,1) model and the discrete GM(1,1) model.

Originality/value

The paper analyses the cause of increasing simulation accuracy of the buffer operator model. The paper may indicate that possible results can be studied in the future. All the buffer operator models have similar properties. After applying an infinite buffer operator, the raw sequence can be changed into a constant sequence. A fixed-point axiom may be the basic cause.

Details

Grey Systems: Theory and Application, vol. 8 no. 1
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 7 November 2016

Sifeng Liu, Naiming Xie, Yingjie Yang and Jeffrey Forrest

The purpose of this paper is to present the terms of sequence operators and grey data mining.

Abstract

Purpose

The purpose of this paper is to present the terms of sequence operators and grey data mining.

Design/methodology/approach

The definitions of basic terms about sequence operators and grey data mining are presented one by one.

Findings

The reader could know the basic explanation about the important terms about sequence operators and grey data mining from this paper.

Practical implications

Many of the colleagues thought that unified definitions of key terms would be beneficial for both the readers and the authors.

Originality/value

It is a fundamental work to standardize all the definitions of terms for a new discipline. It is also propitious to spread the universal principles of grey system theory.

Details

Grey Systems: Theory and Application, vol. 6 no. 3
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 19 August 2011

Dang Luo and Xia Wang

According to the basic principle of grey system and third axiom buffer operator, aiming at the problem of disturbance, some new weakening buffer operators are established by…

218

Abstract

Purpose

According to the basic principle of grey system and third axiom buffer operator, aiming at the problem of disturbance, some new weakening buffer operators are established by analytical skills in the process of prediction. The problem of some contradictions between quantitative analysis and qualitative analysis existing in pretreatment for vibration data sequences is resolved effectively. An example shows that the kind of new weakening buffer operators increase the forecast precision of data forecast model remarkably. The aim of this paper is to attempt to resolve the problem of some contradictions between quantitative analysis and qualitative analysis existing in pretreatment for vibration data sequences.

Design/methodology/approach

In view of the problem of some contradictions between quantitative analysis and qualitative analysis existing in pretreatment for vibration data sequences, according to the basic principle of grey system and third axiom buffer operator, some new weakening buffer operators are established by analytical skills. As an example, the kind of new weakening buffer operators can increase the forecast precision of data forecast model remarkably.

Findings

The results show that the new weakening buffer operators can increase the forecast precision of data forecast model remarkably.

Practical implications

The new weakening buffer operators exposed in the paper can be used to resolve the problem of some contradictions between quantitative analysis and qualitative analysis existing in pretreatment for vibration data sequences and increase the forecast precision of data forecast model remarkably.

Originality/value

The paper succeeds in increasing the forecast precision of data forecast model remarkably.

Details

Grey Systems: Theory and Application, vol. 1 no. 2
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 7 November 2016

Yuanjie Zhi, Dongmei Fu and Hanling Wang

The purpose of this paper is to present a new model which combines the non-equidistant GM(1,1) model with GCHM_WBO (generalized contra-harmonic mean (GCHM); weakening buffer…

Abstract

Purpose

The purpose of this paper is to present a new model which combines the non-equidistant GM(1,1) model with GCHM_WBO (generalized contra-harmonic mean (GCHM); weakening buffer operator (WBO)). The authors use the model to solve the deadlock that for a large number of non-equidistant corrosion rate, it is difficult to establish a reasonable prediction model and improve the prediction accuracy.

Design/methodology/approach

This research consists of three parts: non-equidistant GM(1,1) model, GCHM_WBO operator, and the optimization of morphing parameter (contained in GCHM, control the intensity of the weakening operator). The methodology is explained as follows. First, the authors built a non-equidistant GM(1,1) model with GCHM_WBO weakened data, of which morphing parameter was randomly selected. Next, the authors calculated the error between prediction data of model and the real data, and adjusted the morphing parameter according to the error and property of GCHM. Then, the authors generated a new non-equidistant GM(1,1) based on new morphing parameter, and repeated the previous step until the termination condition was satisfied. Finally, the model with appropriate morphing parameter was used to implement the prediction of new data.

Findings

This paper finds a property of GCHM, which is a monotonic increasing function of morphing parameter in some specific conditions. Based on the property and the fixed point axiom of WBO, an algorithm was designed to search an appropriate morphing parameter. The appropriate morphing parameter was implemented for the purpose of improving the accuracy of the model. The model was applied to predict the corrosion rate of six steels at Guangzhou experimental station. The results showed that the proposed method can get more accuracy in prediction capability compared to the models with the original data and AWBO weakened data. The method is applicable to long-term forecasts in case of data scarcity.

Practical implications

Corrosion will cause huge economic loss to a country; therefore, it is important to judge the remaining useful life of a material or equipment; the foundation for judgement of which is the prediction of material corrosion rate. However, the prediction of corrosion rate is very difficult because of corrosion data’s features, such as small sample size, non-equidistant, etc. The proposed method can be used to implement long-term forecast of corrosion data with only one sample and non-equidistant samples.

Originality/value

This paper presented a model which combines the non-equidistant GM(1,1) model with GCHM_WBO to handle the problem of long-term forecasting of corrosion data. In the modelling process, the proposed morphing parameter searched through algorithm can improve the prediction accuracy of the model. Therefore, the model can provide effective and reliable result when data are of a small sample size and non-equidistant.

Details

Grey Systems: Theory and Application, vol. 6 no. 3
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 1 February 2004

Yi Lin, Mian‐yun Chen and Sifeng Liu

In this paper, we take a look at the state‐of‐the‐art of the theory and applications of the so‐called grey systems theory founded in the 1980s. After a brief historical review of…

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Abstract

In this paper, we take a look at the state‐of‐the‐art of the theory and applications of the so‐called grey systems theory founded in the 1980s. After a brief historical review of the development history of this theory, we look at the main blocks of the theory followed by several successful applications. It is our hope that a reader who does not know anything about this branch of scientific exploration will gain a firm understanding of the basics so that the rest of this special issue becomes possible to comprehend.

Details

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

Keywords

Open Access
Article
Publication date: 9 February 2021

Godwin Amechi Okeke and Daniel Francis

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…

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Abstract

Purpose

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.

Design/methodology/approach

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

Findings

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.

Research limitations/implications

The results are theoretical and analytical.

Practical implications

The results were applied to solving nonlinear integral equations.

Social implications

The results has several social applications.

Originality/value

The results of this paper are new.

Article
Publication date: 25 January 2019

Denis Stijepic

The three-sector framework (relating to agriculture, manufacturing and services) is one of the major concepts for studying the long-run change of the economic structure. This…

Abstract

Purpose

The three-sector framework (relating to agriculture, manufacturing and services) is one of the major concepts for studying the long-run change of the economic structure. This paper aims to discuss the system-theoretical classification of the structural change in the three-sector framework and, in particular, its predictability by the Poincaré–Bendixson theory.

Design/methodology/approach

This study compares the assumptions of the Poincaré–Bendixson theory to the typical axioms of structural change modeling, the empirical evidence on the geometrical properties of structural change trajectories and the methodological arguments referring to the laws of structural change.

Findings

The findings support the assumption that the structural change phenomenon is representable by a dynamical system that is predictable by the Poincaré–Bendixson theory. This result implies, among others, that in the long run, structural change is either transitory or cyclical and can be used in further geometrical/topological long-run structural change modeling and prediction.

Originality/value

Although widespread in mathematics, geometrical/topological modeling methods have not been used in modeling and prediction of long-run structural change, despite the fact that they seem to be predestined for this purpose owing to their global, system-theoretical nature, allowing for a reduction of ideology content of predictions and greater robustness of results.

Details

foresight, vol. 21 no. 2
Type: Research Article
ISSN: 1463-6689

Keywords

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

Article
Publication date: 1 December 2002

Michel Bounias

The non‐well‐founded properties of the empty set provide existence to abstract topological spaces, in which intersections of subspaces with non‐equal dimensions give topologically…

Abstract

The non‐well‐founded properties of the empty set provide existence to abstract topological spaces, in which intersections of subspaces with non‐equal dimensions give topologically closed structures. This let space‐time emerge as an ordered sequence of sections upon a defined combination rule, in which interactivity between observable structures is allowed and conditions for conscious perception phenomena are fulfilled. Conditions for evolution and rules for optimal evolution of ecosystems also infer as corollaries. A physical universe and life constitute one single self‐organized and self managed system where life appears as the physical‐like realization of conditions of functionality of the embedding mathematical spaces. The system includes self‐ethical and moral guidelines which should inspire human behavior on Planet Earth.

Details

Kybernetes, vol. 31 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

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