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Article
Publication date: 20 September 2023

Zhifang Wang, Quanzhen Huang and Jianguo Yu

In this paper, the authors take an amorphous flattened air-ground wireless self-assembling network system as the research object and focus on solving the wireless self-assembling…

Abstract

Purpose

In this paper, the authors take an amorphous flattened air-ground wireless self-assembling network system as the research object and focus on solving the wireless self-assembling network topology instability problem caused by unknown control communication faults during the operation of this system.

Design/methodology/approach

In the paper, the authors propose a neural network-based direct robust adaptive non-fragile fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network integrated system.

Findings

The simulation results show that the system eventually tends to be asymptotically stable, and the estimation error asymptotically tends to zero with the feedback adjustment of the designed controller. The system as a whole has good fault tolerance performance and autonomous learning approximation performance. The experimental results show that the wireless self-assembled network topology has good stability performance and can change flexibly and adaptively with scene changes. The stability performance of the wireless self-assembled network topology is improved by 66.7% at maximum.

Research limitations/implications

The research results may lack generalisability because of the chosen research approach. Therefore, researchers are encouraged to test the proposed propositions further.

Originality/value

This paper designs a direct, robust, non-fragile adaptive neural network fault-tolerant controller based on the Lyapunov stability principle and neural network learning capability. By directly optimizing the feedback matrix K to approximate the robust fault-tolerant correction factor, the neural network adaptive adjustment factor enables the system as a whole to resist unknown control and communication failures during operation, thus achieving the goal of stable wireless self-assembled network topology.

Article
Publication date: 13 October 2021

Zhifang Wang, Jianguo Yu, Shangjing Lin, Junguo Dong and Zheng Yu

The paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, this paper aims to propose a distributed robust H adaptive…

170

Abstract

Purpose

The paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, this paper aims to propose a distributed robust H adaptive fault-tolerant control algorithm suitable for the system to distribute to solve the problem of control and communication failure at the same time.

Design/methodology/approach

In the paper, the authors propose a distributed robust H adaptive fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network-integrated system.

Findings

The results show that the integrated system has good robustness and fault tolerance performance indicators for flight control and wireless signal transmission when confronted with external disturbances, internal actuator failures and wireless network associated failures and the flight control curve of the quadrotor unmanned aerial vehicle (UAV) is generally smooth and stable, even if it encounters external disturbances and actuator failures, its fault tolerance performance is very good. Then in the range of 400–800 m wireless communication distance, the success rate of wireless signal loop transmission is stable at 80%–100% and the performance is at least relatively improved by 158.823%.

Originality/value

This paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, based on the robust fault-tolerant control algorithm, the authors propose a distributed robust H adaptive fault-tolerant control algorithm suitable for the system and through the Riccati equation and linear matrix inequation method, the designed distributed robust H adaptive fault-tolerant controller further optimizes the fault suppression factor γ, so as to break through the limitation of only one Lyapunov matrix for different fault modes to distribute to solve the problem of control and communication failure at the same time.

Article
Publication date: 3 January 2022

Zhifang Wang, Jianguo Yu and Shangjing Lin

To solve the above problems and ensure the stability of the ad hoc network node topology in the process of wireless signal transmission, this paper aims to design a robust…

Abstract

Purpose

To solve the above problems and ensure the stability of the ad hoc network node topology in the process of wireless signal transmission, this paper aims to design a robust adaptive sliding film fault-tolerant controller under the nonlinear distortion of signal transmission in an amorphous flat air-to-ground wireless ad hoc network system.

Design/methodology/approach

This paper designs a robust adaptive sliding film fault-tolerant controller under the nonlinear distortion of signal transmission in an amorphous flat air-to-ground wireless ad hoc network system.

Findings

The simulation results show that the amorphous flat wireless self-organizing network system has good nonlinear distortion fault-tolerant correction ability under the feedback control of the designed controller, and the system has the asymptotically stable convergence ability; the test results show: the node topology of the self-organizing network structural stability is significantly improved, which provides a foundation for the subsequent realization of long-distance transmission of ad hoc network nodes.

Research limitations/implications

Because of the chosen research approach, the research results may lack generalizability. Therefore, researchers are encouraged to test the proposed propositions further.

Originality/value

The controller can extract the fault information caused by nonlinear distortion in the wireless signal transmission process, and at the same time, its feedback matrix K can gradually converge the generated wireless signal error to zero, to realize the stable transmission of the wireless signal.

Article
Publication date: 11 August 2023

Thi Kim Thoa Ninh, Thi Huyen Ngo and Hong Sinh Nguyen

The aim of this paper is to investigate the needs of lecturers and learners for digital scholarship services (DSS) and to suggest recommendations for the development of DSS at…

Abstract

Purpose

The aim of this paper is to investigate the needs of lecturers and learners for digital scholarship services (DSS) and to suggest recommendations for the development of DSS at Vietnam National University Ho Chi Minh City (VNU-HCM).

Design/methodology/approach

The research employed a mixed method approach, comprising a paper questionnaire with 360 respondents to collect quantitative data and in-depth interviews with 18 participants, including lecturers (L), postgraduate students (P), and undergraduate students (U), to gather qualitative data.

Findings

The findings indicate that lecturers and students have diverse needs for various DSS services, with digital information resources and institutional repositories being the most common, followed by new and workable digital technology infrastructure, training courses in using digital tools and methods, and ongoing advice and support at different stages of the research process.

Research limitations/implications

The limitations of this study indicate that further research is necessary to obtain a more comprehensive understanding of the DSS needs in higher education institutions in Vietnam of various sizes and characteristics.

Practical implications

This research provides a practical basis for the development and provision of appropriate support to the development of DSS at VNU-HCM.

Originality/value

The originality of this paper and its value lies in the contribution to the understanding of the needs of DSS in a context of the digital transformation and the improvement of the quality of education and research in the higher education sector in Vietnam.

Details

Library Management, vol. 44 no. 8/9
Type: Research Article
ISSN: 0143-5124

Keywords

Article
Publication date: 19 April 2024

Xiaohong Chen, Qi Shi, Zhifang Zhou and Xu Cheng

Digital transformation misalignment refers to disparities in digital transformation levels between suppliers and buyers across the production and operation process. It has…

Abstract

Purpose

Digital transformation misalignment refers to disparities in digital transformation levels between suppliers and buyers across the production and operation process. It has negatively affected supply chain stability. However, the existing research concerning the economic consequences has not been adequately addressed. Therefore, this paper aims to investigate whether such digital transformation misalignment increases supplier financial risk and to identify the factors influencing this relationship.

Design/methodology/approach

This paper examines binary combinations of suppliers and buyers listed on China’s A-share market between 2011 and 2021. This group constitutes a sample to empirically test the influence of digital transformation misalignment on the supplier’s financial risk, as well as the moderating effect of the geographical and organizational distances.

Findings

The paper’s findings demonstrate that digital transformation misalignment has indeed a significant increase in the supplier’s financial risk. Moreover, the impact is more intense when the geographical or organizational distance between the supplier and the buyer is relatively large.

Originality/value

The existing literature rarely explores the potential risks arising from digital transformation misalignment between supply chain partners. Therefore, this paper fills a notable gap as it is the first to study the impact of digital transformation misalignment on the supplier’s financial risk and the specific applied mechanisms. The contribution significantly improves the field of corporate digital transformation, particularly, within the context of supply chain management.

Details

International Journal of Operations & Production Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0144-3577

Keywords

Article
Publication date: 21 August 2019

Zhifang Zhou, Tao Zhang, Jiachun Chen, Huixiang Zeng and Xiaohong Chen

This paper investigates the relationship between product market competition and firms’ water information disclosure and how firms’ ownership type can affect this relationship in…

Abstract

Purpose

This paper investigates the relationship between product market competition and firms’ water information disclosure and how firms’ ownership type can affect this relationship in China, offering new insights into corporate water management.

Design/methodology/approach

The authors investigated 303 Chinese listed companies in highly water-sensitive industries to examine how product market competition influences corporate water information disclosure by subdividing the product market competition into market competition at the firm level and the industry competition intensity at the industry level.

Findings

The results show that there exists an inverted U-shaped relationship between industry competition and water information disclosure; enterprises with the highest market power in a mildly competitive industry are more willing to voluntarily disclose water information and play an industry benchmarking role. Further tests demonstrate that the relationship between industry competition intensity and water information disclosure is stronger for state-owned enterprises than for private enterprises.

Research limitations/implications

The current water resources regulations in China are relatively lax and the water risk awareness of firms is weak, which may affect the applicability of the results. In addition, water information disclosure research is a relatively new field and a quantitative index system for water information disclosure is still in the exploratory stage. Further developments, including the selection, definition and measuring methods of a water index are required.

Practical implications

The authors developed a new direction of enterprise water management activities from the perspective of market competition. Based on the market conditions in China, the authors also investigated the impact of the ownership type of the enterprises on the relationship between market competition and water information disclosure.

Social implications

The authors suggested that the government should improve laws and regulations and adopt incentive mechanisms to encourage enterprises to implement water resource management. In addition, the government should encourage high market status enterprises to actively fulfill their environmental responsibilities so that the entire industry is encouraged to follow suit.

Originality/value

This study represents an important development in the field of environmental accounting and is the first research on corporate water information disclosure; it also extends the research on the influence mechanisms of market competition on the environmental management practices of enterprises.

Details

Sustainability Accounting, Management and Policy Journal, vol. 11 no. 5
Type: Research Article
ISSN: 2040-8021

Keywords

Article
Publication date: 18 October 2018

Ebru Yazgan and Ayşe Kucuk Yilmaz

Airline business management is set on airworthy strategy. Airline sustainability depends upon corporate-based airworthy strategy as airworthiness is the base to any airline…

Abstract

Purpose

Airline business management is set on airworthy strategy. Airline sustainability depends upon corporate-based airworthy strategy as airworthiness is the base to any airline business management and strategy. An airline can ensize its corporate sustainability if it has airworthiness strategy and risk management. The main condition to survive in the airline business is to maintain airworthiness with the fleet, maintenance and corporate-risk management. Aircraft maintenance technician (AMT) has a dual role in aircraft maintenance system as the source of failure in maintenance process via his volatility and unmanageable qualifications and secondly source of manager of maintain airworthiness of the aircrafts in airline. Situational awareness of managers about both limitations and qualifications of human factors is vital determinant to the decision-making process in aviation. Although continuously improving in related literature, one of the biggest weaknesses of the current methods of AMT error or performance is that the ability to model the reciprocal effects of the factors affecting the fault is limited. For this reason, this study aims to develop an analytic network process (ANP) model that takes into account the effects of mutual dependences among factors.

Design/methodology/approach

Firstly, with the help of experts and extensive literature, 67 factors that contributed to AMT error are identified and grouped. Then, the factors identified as eligible criteria and sub-criteria that contributed to the AMT errors are determined. In this study, the weights of identified criteria that have influence on AMT error try to determine by using ANP method. ANP is the common method to solve multi-criteria decision-making problems and is used to calculate priorities of factors. Criteria determined in this study are classified into three main clusters: “individual-related criteria”, “working environment-related criteria” and “organisational-related criteria”. These main clusters include 15 sub criteria such as communication, documentation (quality/updating/availability) and peer pressure.

Findings

The result of this study shows that time pressure, organisational culture, safety culture and supervision are the most important criteria that contributed to AMT error. Their weights are 0.207, 0.172, 0.102 and 0.094, respectively.

Originality/value

There are many difficulties and limitations in measuring the factors that have an influence on AMT errors. For this reason, the weights of criteria and sub-criteria necessary are determined using ANP, and in this manner, it is possible to make better decisions in this process as ANP is a multi-criteria decision-making technique that considers qualitative factors in decision-making problems. The factors’ taxonomy determined as a result of the expert opinions and the extensive literature and the ANP model developed taking into account the dependencies between the factors will contribute to the literature.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 6 December 2019

Jingyi Wang, Run Yuan and Hongwei Shi

The purpose of this paper is to evaluate the service quality of university library more accurately and dynamically and improve the service efficiency of library. The paper…

Abstract

Purpose

The purpose of this paper is to evaluate the service quality of university library more accurately and dynamically and improve the service efficiency of library. The paper realizes quantified representation of library service quality and overcomes the shortcoming of the traditional library evaluation system, which does not consider reader’s identity and cannot be evaluated separately. In addition, according to the function configuration of each department of library, a relation between library evaluation parameter and its organization structure is built. According to the evaluation results and the chain of relations, some suggestions for improving library service can be put forward; thus, it can improve the quality of library service and management efficiency.

Design/methodology/approach

In this paper, a four-dimensional (4-D) representation method is put forward to express four kinds of parameters, namely, the category of participants, the number of people evaluated, the rating level and the weight of parameters, which is expressed by chromaticity and a three-dimensional column coordinate space. Considering the existing evaluation methods such as LibQUAL+TM, the content of evaluation parameters, the grade of evaluation parameters and the weight of evaluation parameters are modified. Using the volume and the equivalent number of people under this evaluation system, the evaluation grade can be quantified and the total results can be evaluated quantitatively.

Findings

The evaluation model proposed in this paper is a 4-D system that is based on content parameters to evaluate the number of participants, score segments, evaluation content weights and reader information. It gives full consideration to the good advice of many scholars and combines the actual operation of domestic libraries. The situation effectively integrates successful experience abroad. Both the undergraduate and teacher sampling evaluation results and their analysis in this paper show the accuracy and credibility of the method.

Originality/value

Although the satisfaction index model has a good effect in foreign countries, taking into account that readers of university libraries in China are different from those in foreign countries in the evaluation methods of the tutorial, professional multi-level evaluation will produce greater errors in practical applications. The traditional four-level method based on Chinese education evaluation (excellent, good, pass and fail) has reached consensus among teachers and students in practical application, and it is easy to achieve consistency. Therefore, this paper also adopts four-level evaluation, that is, very satisfied, satisfied, generally satisfied and very dissatisfied. The embedded application will be able to perform dynamic evaluation and thus can be used in China. The evaluation of service quality in university libraries provides an effective new method.

Article
Publication date: 28 September 2020

Emad S. Shafik, Medhat L. Tawfic and Adel F. Younan

The purpose of this study is to manufacture composites from sawdust and polymer high-density polyethylene (HDPE) with different loading from alum as natural and cheap flame…

Abstract

Purpose

The purpose of this study is to manufacture composites from sawdust and polymer high-density polyethylene (HDPE) with different loading from alum as natural and cheap flame retardant and subsequently characterized using standard analytical tools.

Design/methodology/approach

Artificial wood plastic composites (WPCs) were prepared by mixing HDPE with sawdust as a filler with constant ratio (2:1) using hot press. Polyethylene-graft-maleic anhydride (PE-g-MAH) used as a coupling agent between two parents of the composites with different ratios (2.5, 5, 7 and 10). Alum as a flame retardant was incorporated into HDPE with 5 phr polyethylene grafted with maleic anhydride (PE-g-MAH) with different ratios (10, 15 and 20). Flame retardant efficiency was investigated using differential scanning calorimetry, thermal gravimetric analysis and the technique of ASTM E162.

Findings

The results revealed that the composite containing 5 phr from (PE-g-MAH) exhibited higher mechanical properties and this proved that (PE-g-MAH) act as an efficient coupling agent using the aforementioned ratio. The results also revealed that incorporation of alum as a flame retardant increased the thermal stability of the composites.

Originality/value

Artificial WPCs are ecofriendly materials with a wide range of applications in the constructions field. Moreover, they have high mechanical and physical properties with low cost. Evaluate alum as a natural and cheap flame retardant.

Details

Pigment & Resin Technology, vol. 50 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 9 January 2023

Leilei Shi, Xinshuai Guo, Andrea Fenu and Bing-Hong Wang

This paper applies a volume-price probability wave differential equation to propose a conceptual theory and has innovative behavioral interpretations of intraday dynamic market…

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Abstract

Purpose

This paper applies a volume-price probability wave differential equation to propose a conceptual theory and has innovative behavioral interpretations of intraday dynamic market equilibrium price, in which traders' momentum, reversal and interactive behaviors play roles.

Design/methodology/approach

The authors select intraday cumulative trading volume distribution over price as revealed preferences. An equilibrium price is a price at which the corresponding cumulative trading volume achieves the maximum value. Based on the existence of the equilibrium in social finance, the authors propose a testable interacting traders' preference hypothesis without imposing the invariance criterion of rational choices. Interactively coherent preferences signify the choices subject to interactive invariance over price.

Findings

The authors find that interactive trading choices generate a constant frequency over price and intraday dynamic market equilibrium in a tug-of-war between momentum and reversal traders. The authors explain the market equilibrium through interactive, momentum and reversal traders. The intelligent interactive trading preferences are coherent and account for local dynamic market equilibrium, holistic dynamic market disequilibrium and the nonlinear and non-monotone V-shaped probability of selling over profit (BH curves).

Research limitations/implications

The authors will understand investors' behaviors and dynamic markets through more empirical execution in the future, suggesting a unified theory available in social finance.

Practical implications

The authors can apply the subjects' intelligent behaviors to artificial intelligence (AI), deep learning and financial technology.

Social implications

Understanding the behavior of interacting individuals or units will help social risk management beyond the frontiers of the financial market, such as governance in an organization, social violence in a country and COVID-19 pandemics worldwide.

Originality/value

It uncovers subjects' intelligent interactively trading behaviors.

Details

China Finance Review International, vol. 13 no. 4
Type: Research Article
ISSN: 2044-1398

Keywords

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