Ruirui Shao, Zhigeng Fang, Liangyan Tao, Su Gao and Weiqing You
During the service period of communication satellite systems, their performance is often degraded due to the depletion mechanism. In this paper, the grey system theory is applied…
Abstract
Purpose
During the service period of communication satellite systems, their performance is often degraded due to the depletion mechanism. In this paper, the grey system theory is applied to the multi-state system effectiveness evaluation and the grey Lz-transformation ADC (availability, dependability and capability) effectiveness evaluation model is constructed to address the characteristics of the communication satellite system such as different constituent subsystems, numerous states and the inaccuracy and insufficiency of data.
Design/methodology/approach
The model is based on the ADC effectiveness evaluation method, combined with the Lz transformation and uses the definite weighted function of the three-parameter interval grey number as a bridge to incorporate the possibility of system performance being greater than the task demand into the effectiveness solution algorithm. At the same time, using MATLAB (Matrix laboratory) to solve each state probability, the same performance level in the Lz transform is combined. Then, the system effectiveness is obtained by Python.
Findings
The results show that the G-Lz-ADC model constructed in this paper can accurately evaluate the effectiveness of static/dynamic systems and certain/uncertain system and also has better applicability in evaluating the effectiveness of the multi-state complex system.
Practical implications
The G-Lz-ADC effectiveness evaluation model constructed in this paper can effectively reduce the complexity of traditional effectiveness evaluation models by combining the same performance levels in the Lz-transform and solving the effectiveness of the system with the help of computer programming, providing a new method for the effectiveness evaluation of the complex MSS. At the same time, the weaknesses of the system can be identified, providing a theoretical basis for improving the system’s effectiveness.
Originality/value
The possibility solution method based on the definite weighted function comparing the two three-parameter interval grey numbers is constructed, which compensates for the traditional calculation of the probability based on numerical values and subjective preferences of decision-makers. Meanwhile, the effectiveness evaluation model integrates the basic theories of three-parameter interval grey number and its definite weighted function, Grey−Markov, grey universal generating function (GUGF), grey multi-state system (GMSS), etc., which is an innovative method to solve the effectiveness of a multi-state instantaneous communication satellite system.
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Shaoguang Zhang, Sifeng Liu, Zhigeng Fang, Qin Zhang and Jingru Zhang
Financial performance has been paid attention at an unprecedented level, which can be confirmed as a fact that the quantitative expansion of financial performance evaluation work…
Abstract
Purpose
Financial performance has been paid attention at an unprecedented level, which can be confirmed as a fact that the quantitative expansion of financial performance evaluation work. The purpose of this study is to propose a more appropriate model for financial performance evaluation under the unbalanced development.
Design/methodology/approach
This paper introduces the differentiation criteria to eliminate the deviation caused by the same principle for multiple performance evaluation objects whose development are unbalanced; Then the generalized grey number is adopted to describe the value of performance evaluation index; and the information entropy weight is used to obtain the index weight to reduce the artificial judgment error; Finally, the generalized grey information entropy weight TOPSIS evaluation model is constructed.
Findings
Empirical research shows that in the new evaluation model, the differentiated possibility function effectively eliminates the deviation caused by the same principle, the application of information entropy weight reduces the human judgment error, and the value of generalized grey number further enhances the closeness of the results. Moreover, it is also found that in different scenarios, an adaptive performance evaluation model should be selected to match scientifically reasonable results.
Originality/value
The proposed model offers a solution for financial performance evaluation considering unbalanced development among cities. It can be realized by determining the differentiation possibility function matrix, and then the information entropy weight TOPSIS evaluation model can be constructed. This model reflects the actual situation, improves the performance evaluation accuracy, and can be used under similar conditions.
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Abstract
The spatial design of a building affects the movement of occupants. In complex buildings with a large population, such as places of assembly, the movement of people towards the exits under emergency situations is a major concern. Ideally, people should leave the building smoothly under emergency situations. Traditionally the layout design is governed by the building fire codes. However, the building fire codes merely govern the design of the capacity of individual components, and do not guarantee that smooth egress will occur. Full‐scale egress exercises may be needed to examine the layout arrangement in order to understand the layout problem. However, such exercises may be time‐consuming, or may be impossible when the building has yet to be constructed. Therefore, the use of computer models to simulate the egress pattern can assist not only the building designer, but also the facility manager to plan the spatial arrangement as well as to manage the crowd flow during emergency situations. Discusses the use of a computer model for analysing building layout design.
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Elvis Achuo, Pilag Kakeu and Simplice Asongu
Despite the global resolves to curtail fossil fuel consumption (FFC) in favour of clean energies, several countries continue to rely on carbon-intensive sources in meeting their…
Abstract
Purpose
Despite the global resolves to curtail fossil fuel consumption (FFC) in favour of clean energies, several countries continue to rely on carbon-intensive sources in meeting their energy demands. Financial constraints and limited knowledge with regards to green energy sources constitute major setbacks to the energy transition process. This study therefore aims to examine the effects of financial development and human capital on energy consumption.
Design/methodology/approach
The empirical analysis is based on the system generalised method of moments (SGMM) for a panel of 134 countries from 1996 to 2019. The SGMM estimates conducted on the basis of three measures of energy consumption, notably fossil fuel, renewable energy as well as total energy consumption (TEC), provide divergent results.
Findings
While financial development significantly reduces FFC, its effect is positive though non-significant with regards to renewable energy consumption. Conversely, financial development has a positive and significant effect on TEC. Moreover, the results reveal that human capital development has an enhancing though non-significant effect on the energy transition process. In addition, the results reveal that resource rents have an enhancing effect on the energy transition process. However, when natural resources rents are disaggregated into various components (oil, coal, mineral, natural gas and forest rents), the effects on energy transition are divergent. Although our findings are consistent when the global panel is split into developed and developing economies, the results are divergent across geographical regions. Contingent on these findings, actionable policy implications are discussed.
Originality/value
The study complements extant literature by assessing nexuses between financial development, human capital and energy transition from a global perspective.
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Surya Prakash, Anubhav Agrawal, Ranbir Singh, Rajesh Kumar Singh and Divya Zindani
Grey Systems: Theory and Application (GSTA) journal started publication in 2011 and completed a decade in 2021. The purpose of this study is to provide a detailed bibliometric…
Abstract
Purpose
Grey Systems: Theory and Application (GSTA) journal started publication in 2011 and completed a decade in 2021. The purpose of this study is to provide a detailed bibliometric analysis of the articles published in GSTA and their content primary trends and themes.
Design/methodology/approach
This study uses the Web of Science (WoS) database to analyze the content of published articles. A range of bibliometric analyses and indicators are applied to analyze the GSTA article content using science mapping tools of the Bibliometrix package in the R environment.
Findings
The GSTA publishes around 28 articles each year with citations of this work steadily growing over time. The impact of these publications is measured as total mean citations which increased from 0 to 11. The journal has attracted contributors from around the globe, most often affiliated with China, India and Europe. Thematic evolution of the journal's themes reveals that it has expanded its scope to include topics such as relational analysis, decision making, incidence analysis, and forecasting, hybrid grey-fuzzy or grey-rough modeling, etc.
Research limitations/implications
The study is majorly based on GSTA data available on the WoS database.
Originality/value
This study provides the first overview of GSTA's publication and citation trends as well as the evolution of its thematic structure. It also suggests future directions that the journal might take to strengthen its position.
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Zhengwei Song, Shengjian Zhang, Lifeng Ding, Xuejing Wu and Ning Long
The purpose of this paper was prepared a Ni-based superhydrophobic coating on the surface of copper to enhence its corrosion resistance. The superhydrophobic coating (SHPC) has…
Abstract
Purpose
The purpose of this paper was prepared a Ni-based superhydrophobic coating on the surface of copper to enhence its corrosion resistance. The superhydrophobic coating (SHPC) has proven to be an effective surface treatment in corrosion protection. In this paper, a Ni-based SHPC was prepared on the surface of copper (Cu) to enhance its corrosion resistance.
Design/methodology/approach
The coating was prepared through a two-step electrodeposition process. The first step involves the formation of a micro-nano structure Ni layer formed by an electrodeposition process. Subsequently, the polysiloxane layer was deposited on the Ni surface to create an SHPC. The morphology, composition, structure, wettability and corrosion resistance of the coating were characterized and discussed.
Findings
The results show that the water contact angle of the as-prepared coating reaches 155.5°±1.0°. The corrosion current density (icorr = 3.90 × 10−9 A·cm−2) decreased by three orders of magnitude compared to the substrate, whereas |Z|f = 0.01 Hz (2.40 × 106 Ω·cm2) increased by three orders of magnitude. It indicated that the prepared coating has excellent superhydrophobicity and high corrosion resistance, which can provide better protection for the substrate.
Originality/value
The prepared coating provides long-lasting protection for Cu and other metals and offers valuable data for developing SHPCs.
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Yi Xia, Yonglong Li, Hongbin Zang, Yanpian Mao, Haoran Wang and Jialong Li
A switching depth controller based on a variable buoyancy system (VBS) is proposed to improve the performance of small autonomous underwater vehicles (AUVs). First, the…
Abstract
Purpose
A switching depth controller based on a variable buoyancy system (VBS) is proposed to improve the performance of small autonomous underwater vehicles (AUVs). First, the requirements of VBS for small AUVs are analyzed. Second, a modular VBS with high extensibility and easy integration is proposed based on the concepts of generality and interchangeability. Subsequently, a depth-switching controller is proposed based on the modular VBS, which combines the best features of the linear active disturbance rejection controller and the nonlinear active disturbance rejection controller.
Design/methodology/approach
The controller design and endurance of tiny AUVs are challenging because of their low environmental adaptation, limited energy resources and nonlinear dynamics. Traditional and single linear controllers cannot solve these problems efficiently. Although the VBS can improve the endurance of AUVs, the current VBS is not extensible for small AUVs in terms of the differences in individuals and operating environments.
Findings
The switching controller’s performance was examined using simulation with water flow and external disturbances, and the controller’s performance was compared in pool experiments. The results show that switching controllers have greater effectiveness, disturbance rejection capability and robustness even in the face of various disturbances.
Practical implications
A high degree of standardization and integration of VBS significantly enhances the performance of small AUVs. This will help expand the market for small AUV applications.
Originality/value
This solution improves the extensibility of the VBS, making it easier to integrate into different models of small AUVs. The device enhances the endurance and maneuverability of the small AUVs by adjusting buoyancy and center of gravity for low-power hovering and pitch angle control.
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Xiang Gong, Zhenxin Xiao, Xiaoxiao Liu and Matthew K.O. Lee
Active participation is critical to the survival and development of the multiplayer online battle arena (MOBA) game community. However, this issue has not received much attention…
Abstract
Purpose
Active participation is critical to the survival and development of the multiplayer online battle arena (MOBA) game community. However, this issue has not received much attention in the information systems literature. To address this issue, we develop a tripartite model that accounts for the roles of behavioral dedication, constraint, obligation mechanisms on active participation in the MOBA community.
Design/methodology/approach
The research model is empirically validated by online survey data among 971 users of a popular MOBA community.
Findings
The results show that perceived enjoyment, perceived escapism, and affective commitment are key behavioral dedication factors, which further promote active participation in the MOBA community. In addition, past investment, self-efficacy for change, and calculative commitment are important behavioral constraint factors, which ultimately influence active participation in the MOBA community. Finally, subjective norm, group norm, social identity, and normative commitment are influential behavioral obligation factors, which in turn facilitate active participation in the MOBA community.
Originality/value
This study contributes to the theoretical understanding of active participation in the MOBA community and offers practical guidance for promoting active participation in the community.
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Wenjie Dong, Sifeng Liu and Zhigeng Fang
The purpose of this paper is to study the modelling mechanisms of several grey incidence analysis models with great influence, including Deng’s grey incidence model, absolute…
Abstract
Purpose
The purpose of this paper is to study the modelling mechanisms of several grey incidence analysis models with great influence, including Deng’s grey incidence model, absolute degree of grey incidence model, slope degree of incidence model, similitude degree of incidence model and closeness degree of incidence model; then analyse the problems to be solved in grey incidence analysis models; and clarify the applicable ranges of commonly used grey incidence models.
Design/methodology/approach
The paper comes to conclusions by means of comparable analysis. The authors compare several commonly used grey incidence analysis models, including Deng’s grey incidence model, absolute degree of grey incidence model, slope degree of incidence model, similitude degree of incidence model and closeness degree of incidence model and give several examples to clarify the reasons why quantitative analysis results of different models are not exactly the same.
Findings
As the intension of each kind of incidence model is clear and the extension is relatively obscure, grey incidence orders calculated by different incidence models are often different. When making actual decisions, incompatible results may appear. According to different characteristics of extraction, grey incidence analysis models can be divided into three types: incidence model based on closeness perspective, incidence model based on similarity perspective and incidence model based on comprehensive perspective.
Practical implications
The conclusions obtained in this paper can help people avoid some defects in the process of actual selection and choose the better incidence analysis model.
Originality/value
The conclusions can be used as a reference and basis for the selection of grey incidence analysis models, it can help to overcome the defects and shortcomings of models caused by themselves and screen out more excellent analytical models.