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1 – 10 of over 147000Mahmoud Taban and Alireza Basohbat Novinzadeh
One of the challenges encountered in the design of guided projectiles is their prohibitive cost. To diminish it, an appropriate avenue many researchers have explored is the use of…
Abstract
Purpose
One of the challenges encountered in the design of guided projectiles is their prohibitive cost. To diminish it, an appropriate avenue many researchers have explored is the use of the non-actuator method for guiding the projectile to the target. In this method, biologically inspired by the flying concept of the single-winged seed, for instance, that of maple and ash trees, the projectile undergoes a helical motion to scan the region and meet the target in the descent phase. Indeed, the projectile is a decelerator device based on the autorotation flight while it attempts to resemble the seed’s motion using two wings of different spans. There exists a wealth of studies on the stability of the decelerators (e.g. the mono-wing, samara and pararotor), but all of them have assumed the body (exclusive of the wing) to be symmetric and paid no particular attention to the scanning quality of the region. In practice, however, the non-actuator-guided projectiles are asymmetric owing to the presence of detection sensors. This paper aims to present an analytical solution for stability analysis of asymmetric decelerators and apprise the effects of design parameters to improve the scanning quality.
Design/methodology/approach
The approach of this study is to develop a theoretical model consisting of Euler equations and apply a set of non-dimensionalized equations to reduce the number of involved parameters. The obtained governing equations are readily applicable to other decelerator devices, such as the mono-wing, samara and pararotor.
Findings
The results show that the stability of the body can be preserved under certain conditions. Moreover, pertinent conclusions are outlined on the sensitivity of flight behavior to the variation of design parameters.
Originality/value
The analytical solution and sensitivity analysis presented here can efficiently reduce the design cost of the asymmetric decelerator.
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Xiaowei An, Sicheng Ren, Lunyan Wang and Yehui Huang
The purpose of this paper is to explore the support for multi-party collaboration in project construction provided by building information modeling (BIM). Based on the perspective…
Abstract
Purpose
The purpose of this paper is to explore the support for multi-party collaboration in project construction provided by building information modeling (BIM). Based on the perspective of value co-creation, the research results can provide support for the collaborative application and contract design of BIM platform.
Design/methodology/approach
In this paper, an evolutionary game model involving the owner, designer and constructor is constructed by using prospect theory and evolutionary game theory. Through simulation analysis, the evolution law of the strategy choice of each party in the collaborative application of BIM platform is discussed and the key factors affecting the strategy choice of all parties are analyzed.
Findings
The results show that there is an ideal local equilibrium point with progressive stability in the evolutionary game between the three parties: “the construction party shares information, the designer receives the information and optimizes the project and the owner does not provide incentives”; in addition, the opportunistic behaviors of the design and construction parties, as well as the probability of such behaviors being detected and the subsequent punishment have a significant impact on the evolutionary outcome.
Originality/value
This method can provide support for the collaborative application and contract design of BIM platform.
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Bingwei Gao, Hongjian Zhao, Wenlong Han and Shilong Xue
This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and…
Abstract
Purpose
This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and verifies its decoupling effect..
Design/methodology/approach
The machine–hydraulic cross-linking coupling is studied as the coupling behavior of the hydraulically driven quadruped robot, and the mechanical dynamics coupling force of the robot system is controlled as the disturbance force of the hydraulic system through the Jacobian matrix transformation. According to the principle of multivariable decoupling, a prediction-based neural network model reference decoupling control method is proposed; each module of the control algorithm is designed one by one, and the stability of the system is analyzed by the Lyapunov stability theorem.
Findings
The simulation and experimental research on the robot joint decoupling control method is carried out, and the prediction-based neural network model reference decoupling control method is compared with the decoupling control method without any decoupling control method. The results show that taking the coupling effect experiment between the hip joint and knee joint as an example, after using the predictive neural network model reference decoupling control method, the phase lag of the hip joint response line was reduced from 20.3° to 14.8°, the amplitude attenuation was reduced from 1.82% to 0.21%, the maximum error of the knee joint coupling line was reduced from 0.67 mm to 0.16 mm and the coupling effect between the hip joint and knee joint was reduced from 1.9% to 0.48%, achieving good decoupling.
Originality/value
The prediction-based neural network model reference decoupling control method proposed in this paper can use the neural network model to predict the next output of the system according to the input and output. Finally, the weights of the neural network are corrected online according to the predicted output and the given reference output, so that the optimization index of the neural network decoupling controller is extremely small, and the purpose of decoupling control is achieved.
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Enes Mahmut Göker, Ahmet Fevzi Bozkurt and Kadir Erkan
The purpose of this paper is to introduce a novel cross (+) type yoke with hybrid electromagnets and new reluctance modeling to precisely calculate attraction force is given.
Abstract
Purpose
The purpose of this paper is to introduce a novel cross (+) type yoke with hybrid electromagnets and new reluctance modeling to precisely calculate attraction force is given.
Design/methodology/approach
The comparison of attraction force and torque analyses between the proposed formulation and the existing formulation in the literature is comparatively presented. For the correctness of the force and torque values calculated in the model created, the system was created in ANSYS Maxwell and its accuracy was proved by making analyses. The maglev carrier system is inherently unstable from the point of view of control engineering. For that, it needs an active controller to eliminate this instability. For the levitation of the carrier system, it is necessary to design a controller in three axes (z, α and β). I-PD controller was designed for the air gap control of the carrier system in three axes and the controller parameters were determined by the canonical method.
Findings
While the new formulation proposed in the modeling of the carrier system has a maximum error of 1.03%, the existing formula in the literature has an error of 16.83% in the levitation distance point.
Originality/value
A novel cross-type hybrid carrier system has been proposed in the literature. With the double integral used in modeling the system, it takes a long time to solve symbolically, and it is difficult to simulate dynamic behavior in control validation. To solve this problem, attraction force and inclination torque values are easily characterized by new formulation and besides the simulations are conducted easily. The experimental setup was manufactured and assembled, and the carrier system was successfully levitated, and reference tracking was performed without overshoot.
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This study aims to investigate two newly developed (3 + 1)-dimensional Kairat-II and Kairat-X equations that illustrate relations with the differential geometry of curves and…
Abstract
Purpose
This study aims to investigate two newly developed (3 + 1)-dimensional Kairat-II and Kairat-X equations that illustrate relations with the differential geometry of curves and equivalence aspects.
Design/methodology/approach
The Painlevé analysis confirms the complete integrability of both Kairat-II and Kairat-X equations.
Findings
This study explores multiple soliton solutions for the two examined models. Moreover, the author showed that only Kairat-X give lump solutions and breather wave solutions.
Research limitations/implications
The Hirota’s bilinear algorithm is used to furnish a variety of solitonic solutions with useful physical structures.
Practical implications
This study also furnishes a variety of numerous periodic solutions, kink solutions and singular solutions for Kairat-II equation. In addition, lump solutions and breather wave solutions were achieved from Kairat-X model.
Social implications
The work formally furnishes algorithms for studying newly constructed systems that examine plasma physics, optical communications, oceans and seas and the differential geometry of curves, among others.
Originality/value
This paper presents an original work that presents two newly developed Painlev\'{e} integrable models with insightful findings.
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Junsung Park, Joon Woo Yoo, Youngju Cho and Heejun Park
This study aims to understand the reasons for individuals switching from traditional banks to Internet-only banks and examine how switching intentions differ between Generation X…
Abstract
Purpose
This study aims to understand the reasons for individuals switching from traditional banks to Internet-only banks and examine how switching intentions differ between Generation X and Generation Z. Notably, Generation Z, being digital natives, exhibits distinct characteristics compared to Generation X, who often referred to as digital immigrants. Given the technology-driven nature of Internet-only banks, a multi-group analysis between these two generations was conducted.
Design/methodology/approach
This study utilizes Bansal’s push–pull–mooring model as a framework to analyze switching intention. The study collected survey data from 383 Korean participants, consisting of 198 participants from Generation Z and 185 participants from Generation X.
Findings
The findings indicate that low satisfaction and discomfort are factors that push people to leave traditional banks. Specifically, Generation Z shows a significantly higher inclination to leave traditional banks due to discomfort. On the other hand, relative advantage, compatibility, observability and trialability are factors that pull people to switch to Internet-only banks. Generation X is more likely to consider adopting Internet-only banks when compatibility is high and complexity is low.
Originality/value
This study is the first to explore unique motivators for Generation Z, such as their discomfort with interpersonal interactions in the retail banking sector. These findings challenge earlier research emphasizing human interaction’s importance in technology adoption, offering insights into their future adoption of contactless services.
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Hedi Khedhiri and Taher Mkademi
In this paper we talk about complex matrix quaternions (biquaternions) and we deal with some abstract methods in mathematical complex matrix analysis.
Abstract
Purpose
In this paper we talk about complex matrix quaternions (biquaternions) and we deal with some abstract methods in mathematical complex matrix analysis.
Design/methodology/approach
We introduce and investigate the complex space
Findings
We develop on
Originality/value
We give sufficient and necessary conditions in terms of Cauchy–Riemann type quaternionic differential equations for holomorphicity of a function of one complex matrix variable
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This paper constructs a tripartite evolutionary game model between the government, the core enterprises of film copyright export and imports and uses the system dynamics model to…
Abstract
Purpose
This paper constructs a tripartite evolutionary game model between the government, the core enterprises of film copyright export and imports and uses the system dynamics model to simulate and find the optimal selection results of single and mixed government incentives under dynamic changes, aiming to promote the development of foreign trade of film copyright and innovation and development of the film industry so as to improve the overall social benefits of the film industry and provide policy enlightenment for enhancing the import power of foreign core enterprises to introduce domestic film copyrights.
Design/methodology/approach
In this paper, a tripartite evolutionary game model of the government, the core enterprises of film copyright export and imports is constructed, the evolution process of cooperation strategy is derived, the impact of innovation income coefficient, mixed incentive policy and single incentive policy on the evolution results is analyzed, and the system dynamic model is used to simulate to find the optimal selection results of single and mixed government incentives under dynamic changes, so as to provide reference for the government’s dynamic incentive decision-making.
Findings
The results show that export-oriented core firms are more sensitive to mixed incentives, while import-oriented core firms respond more quickly to single incentives. The large innovation income coefficient has a negative impact on the willingness of import-oriented core enterprises to cooperate. The study proposes measures to increase the willingness of core companies to participate.
Research limitations/implications
Due to the fact that numerical simulation is based on simulation, there may be a certain gap between it and the actual situation. Therefore, it is necessary to further use actual data to conduct empirical analysis on the theoretical model.
Practical implications
This article mainly focuses on analyzing the impact of strategy choices and related parameters of various entities on the incentive mechanism and studying the foreign trade cooperation strategies of film copyright export enterprises under policy support from a theoretical model perspective. Furthermore, research has proven that in order to effectively enhance the willingness of foreign import core enterprises to participate in the foreign trade of domestic film copyrights, the government needs to coordinate the use of single incentive policies and mixed incentive policies. This study provides a major contribution for policymaker to develop film copyright import and export trade.
Social implications
Based on the research conclusions, this paper puts forward management countermeasures to further improve the development of the film copyright import and export trade. The first is to enrich government incentive methods and stimulate the vitality of film copyright and foreign trade market entities. The second is to guide the core enterprises of film copyright export to increase investment in innovation and stimulate the endogenous driving force of industrial development. Finally, lengthen the foreign trade industry chain of film copyright and increase the income of film derivatives.
Originality/value
Firstly, this paper applies the research methods of evolutionary game and system dynamics simulation to the field of foreign trade research on film copyright and expands the research perspectives and methods of the film industry. Secondly, by analyzing the “cost-benefit incentive” relationship of the evolutionary game of government export-oriented core enterprises and importing core enterprises, an evolutionary game model is constructed, the quantitative point of tripartite interest decision-making is solved and the research object of the evolutionary game method is expanded. Finally, the system dynamics model is used to simulate and find the optimal selection results of single and mixed government incentives under dynamic changes, so as to provide reference for the government’s dynamic incentive decision-making.
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Mare Stevanovski, Likun (David) Zhan and Michael Mustafa
This paper highlights the opportunities and challenges for family firms in managing Generation Z (Gen-Z) employees. This perspective article explores several considerations for…
Abstract
Purpose
This paper highlights the opportunities and challenges for family firms in managing Generation Z (Gen-Z) employees. This perspective article explores several considerations for family firms in managing their Gen-Z employees and the potential implications for their socioemotional wealth (SEW).
Design/methodology/approach
The authors provide a brief review of what is known about the values/work habits of Gen-Z employees and attracting, retaining and managing nonfamily employees in family firms.
Findings
The unique values, motivations and working styles of Gen-Z employees suggest the need for family business leaders to adopt a different approach to managing these employees. A focus on Gen-Z’s psychological contract, technological savviness and entrepreneurial orientation is provided with respect to how they can be managed.
Originality/value
The authors suggest the importance of approaching NFEs as a heterogenous group and offer avenues for future research with prospective research questions to better understand nonfamily Generation Z employees’ place in the family firm.
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