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Article
Publication date: 24 September 2018

Sifeng Liu, Zhigeng Fang, Naiming Xie and Yingjie Yang

Abstract

Details

Grey Systems: Theory and Application, vol. 8 no. 4
Type: Research Article
ISSN: 2043-9377

Article
Publication date: 7 June 2021

Shixiong Wu, Zhiming Gao, Da-Hai Xia, Meijun Wu, Yingjie Liu and Wenbin Hu

This paper aims to study the effect of temperature on the process and kinetic parameters of the hydrogen evolution reaction of X80 under cathodic protection (CP) in 3.5% NaCl…

Abstract

Purpose

This paper aims to study the effect of temperature on the process and kinetic parameters of the hydrogen evolution reaction of X80 under cathodic protection (CP) in 3.5% NaCl solution.

Design/methodology/approach

Potentiodynamic polarization combined with the hydrogen permeation test is used to analyze the hydrogen evolution reaction (HER) process and the rate-determining step for which is diagnosed through the electrochemical impedance spectrum method. Then, the influence of temperature on kinetic parameters of HER can be known from the results obtained by using the Iver-Pickering-Zamenzadeh model for data analysis.

Findings

The results show that the HER proceeds through Volmer–Tafel route with the Volmer reaction acting as the rate-controlling step; Increasing temperature gives a higher activity of the HER on X80, it also accelerates the hydrogen desorption and diffusion of hydrogen into the metal.

Originality/value

There exist few studies on the topic of how temperature affects the HER process. It is imperative to conduct a relevant study to give some instruction in cathodic protection system design and this paper fulfills this need.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 6 November 2019

Caiyun Sun

The purpose of this paper is to analyze the reliability and validity of doctoral candidates’ innovative personality model.

Abstract

Purpose

The purpose of this paper is to analyze the reliability and validity of doctoral candidates’ innovative personality model.

Design/methodology/approach

Based on doctoral candidates’ innovative personality model, this study took the best correlation and the worst correlation into account to predict and demonstrate their innovative ability tendencies. Matlab R2016a, a program of software programming, was used to calculate the contribution degree of each personality factor of doctoral candidates to their innovative ability tendencies.

Findings

The reliability and validity of doctoral candidates’ innovative personality model based on grey target theory have been verified, and the prediction for doctoral candidates’ innovative ability tendencies can be realized on the basis of this model.

Practical implications

Scientific and reasonable doctoral candidates’ innovative personality model can play a good guiding role, and its research results have certain practical significance for selecting innovative doctoral candidates, ensuring the training quality of doctoral candidates and cultivating the innovative ability of doctoral candidates. It can be promoted and applied on the basis of its trial operation in Jiangsu.

Originality/value

With regard to the relative degree of the influence of doctoral candidates’ individual personality factors, previous researchers seldom carried out the quantitative research. In this paper, the author sought a quantitative method to describe the degree of such influence and constructed the doctoral candidates’ innovative personality model based on grey target decision making. This study took the positive and negative off-target distance into account and demonstrated the rationality and validity of doctoral candidates’ innovative personality model.

Details

Grey Systems: Theory and Application, vol. 10 no. 1
Type: Research Article
ISSN: 2043-9377

Keywords

Content available
Article
Publication date: 28 January 2019

Sifeng Liu and Yingjie Yang

Abstract

Details

Grey Systems: Theory and Application, vol. 9 no. 1
Type: Research Article
ISSN: 2043-9377

Article
Publication date: 7 November 2016

Sifeng Liu, Yingjie Yang, Jeffrey Forrest and Handan Rui

The purpose of this paper is to present the terms of concepts and fundamental principles of grey systems.

Abstract

Purpose

The purpose of this paper is to present the terms of concepts and fundamental principles of grey systems.

Design/methodology/approach

The definitions of basic terms about concepts and fundamental principles of grey systems are presented one by one.

Findings

The reader could know the basic explanation about the important terms about concepts and fundamental principles of grey systems from this paper.

Practical implications

Many of the authors’ 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

Content available
Article
Publication date: 3 August 2015

Delcea Camelia

142

Abstract

Details

Grey Systems: Theory and Application, vol. 5 no. 2
Type: Research Article
ISSN: 2043-9377

Content available
Article
Publication date: 7 November 2016

Sifeng Liu

626

Abstract

Details

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

Article
Publication date: 24 April 2020

Ariel Mutegi Mbae and Nnamdi I. Nwulu

In the daily energy dispatch process in a power system, accurate short-term electricity load forecasting is a very important tool used by spot market players. It is a critical…

Abstract

Purpose

In the daily energy dispatch process in a power system, accurate short-term electricity load forecasting is a very important tool used by spot market players. It is a critical requirement for optimal generator unit commitment, economic dispatch, system security and stability assessment, contingency and ancillary services management, reserve setting, demand side management, system maintenance and financial planning in power systems. The purpose of this study is to present an improved grey Verhulst electricity load forecasting model.

Design/methodology/approach

To test the effectiveness of the proposed model for short-term load forecast, studies made use of Kenya’s load demand data for the period from January 2014 to June 2019.

Findings

The convectional grey Verhulst forecasting model yielded a mean absolute percentage error of 7.82 per cent, whereas the improved model yielded much better results with an error of 2.96 per cent.

Practical implications

In the daily energy dispatch process in a power system, accurate short-term load forecasting is a very important tool used by spot market players. It is a critical ingredient for optimal generator unit commitment, economic dispatch, system security and stability assessment, contingency and ancillary services management, reserve setting, demand side management, system maintenance and financial planning in power systems. The fact that the model uses actual Kenya’s utility data confirms its usefulness in the practical world for both economic planning and policy matters.

Social implications

In terms of generation and transmission investments, proper load forecasting will enable utilities to make economically viable decisions. It forms a critical cog of the strategic plans for power utilities and other market players to avoid a situation of heavy stranded investment that adversely impact the final electricity prices and the other extreme scenario of expensive power shortages.

Originality/value

This research combined the use of natural logarithm and the exponential weighted moving average to improve the forecast accuracy of the grey Verhulst forecasting model.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 5
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 6 February 2017

Sifeng Liu, Hongyang Zhang and Yingjie Yang

The purpose of this paper is to present the terms of grey incidence analysis models.

Abstract

Purpose

The purpose of this paper is to present the terms of grey incidence analysis models.

Design/methodology/approach

The definitions of basic terms about various grey incidence analysis models are presented one by one.

Findings

The reader could know the basic explanation about the important terms about various grey incidence analysis models from this paper.

Practical implications

Many of the authors’ 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 and universal of grey system theory.

Details

Grey Systems: Theory and Application, vol. 7 no. 1
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 6 February 2017

Sifeng Liu and Yingjie Yang

The purpose of this paper is to present the terms of grey forecasting models and techniques.

Abstract

Purpose

The purpose of this paper is to present the terms of grey forecasting models and techniques.

Design/methodology/approach

The definitions of basic terms about grey forecasting models and techniques are presented one by one.

Findings

The reader could know the basic explanation about the important terms about various grey forecasting models and techniques from this paper.

Practical implications

Many of the authors’ 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 standardise all the definitions of terms for a new discipline. It is also propitious to spread and universal of grey system theory.

1 – 10 of 124