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1 – 10 of over 2000Yiwei Zhang, Daochun Li, Zi Kan, Zhuoer Yao and Jinwu Xiang
This paper aims to propose a novel control scheme and offer a control parameter optimizer to achieve better automatic carrier landing. Carrier landing is a challenging work…
Abstract
Purpose
This paper aims to propose a novel control scheme and offer a control parameter optimizer to achieve better automatic carrier landing. Carrier landing is a challenging work because of the severe sea conditions, high demand for accuracy and non-linearity and maneuvering coupling of the aircraft. Consequently, the automatic carrier landing system raises the need for a control scheme that combines high robustness, rapidity and accuracy. In addition, to exploit the capability of the proposed control scheme and alleviate the difficulty of manual parameter tuning, a control parameter optimizer is constructed.
Design/methodology/approach
A novel reference model is constructed by considering the desired state and the actual state as constrained generalized relative motion, which works as a virtual terminal spring-damper system. An improved particle swarm optimization algorithm with dynamic boundary adjustment and Pareto set analysis is introduced to optimize the control parameters.
Findings
The control parameter optimizer makes it efficient and effective to obtain well-tuned control parameters. Furthermore, the proposed control scheme with the optimized parameters can achieve safe carrier landings under various severe sea conditions.
Originality/value
The proposed control scheme shows stronger robustness, accuracy and rapidity than sliding-mode control and Proportion-integration-differentiation (PID). Also, the small number and efficiency of control parameters make this paper realize the first simultaneous optimization of all control parameters in the field of flight control.
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Heji Zhang, Dezhao Lu, Wei Pan, Xing Rong and Yongtao Zhang
The purpose of this study is to design a closed hydrostatic guideway has the ability to resist large-side load, pitch moments and yaw moments, has good stiffness and damping…
Abstract
Purpose
The purpose of this study is to design a closed hydrostatic guideway has the ability to resist large-side load, pitch moments and yaw moments, has good stiffness and damping characteristics, and provides certain beneficial guidance for the design of large-span closed hydrostatic guideway on the basis of providing a large vertical load bearing capacity.
Design/methodology/approach
The Reynolds’ equation and flow continuity equation are solved simultaneously by the finite difference method, and the perturbation method and the finite disturbance method is used for calculating the dynamic characteristics. The static and dynamic characteristics, including recess pressure, flow of lubricating oil, carrying capacity, pitch moment, yaw moment, dynamic stiffness and damping, are comprehensively analyzed.
Findings
The designed closed hydrostatic guideway has the ability to resist large lateral load, pitch moment and yaw moment and has good stiffness and damping characteristics, on the basis of being able to provide large vertical carrying capacity, which can meet the application requirements of heavy two-plate injection molding machine (TPIMM).
Originality/value
This paper researches static and dynamic characteristics of a large-span six-slider closed hydrostatic guideway used in heavy TPIMM, emphatically considering pitch moment and yaw moment. Some useful guidance is given for the design of large-span closed hydrostatic guideway.
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Quanwei Yin, Liang Zhang and Xudong Zhao
This paper aims to study the issues of output reachable set estimation for the linear singular Markovian jump systems (SMJSs) with time-varying delay based on a proportional plus…
Abstract
Purpose
This paper aims to study the issues of output reachable set estimation for the linear singular Markovian jump systems (SMJSs) with time-varying delay based on a proportional plus derivative (PD) bumpless transfer (BT) output feedback (OF) control scheme.
Design/methodology/approach
To begin with, a sufficient criterion is given in the form of a linear matrix inequality based on the Lyapunov stability theory. Then, a PD-BT OF controller is designed to keep all the output signs of the system are maintain within a predetermined ellipsoid. Finally, numerical and practical examples are used to demonstrate the efficiency of the approach.
Findings
Based on PD control and BT control method, an OF control strategy for the linear SMJSs with time-varying delay is proposed.
Originality/value
The output reachable set synthesis of linear SMJSs with time-varying delay can be solved by using the proposed approach. Besides, to obtain more general results, the restrictive assumptions of some parameters are removed. Furthermore, a sufficiently small ellipsoid can be obtained by the design scheme adopted in this paper, which reduces the conservatism of the existing results.
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Our result of this paper aims to indicate that the beta pricing formula could be applied in a long-term model setting as well.
Abstract
Purpose
Our result of this paper aims to indicate that the beta pricing formula could be applied in a long-term model setting as well.
Design/methodology/approach
In this paper, we show that the capital asset pricing model can be derived from a three-period general equilibrium model.
Findings
We show that our extended model yields a Pareto efficient outcome.
Practical implications
The capital asset pricing model (CAPM) model can be used for pricing long-lived assets.
Social implications
Long-term modelling and sustainability can be modelled in our setting.
Originality/value
Our results were only known for two periods. The extension to 3 periods opens up a large scope of applicational possibilities in asset pricing, behavioural analysis and long-term efficiency.
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Aziean Jamin, Gbolahan Gbadamosi and Svetla Stoyanova-Bozhkova
This paper reviews the literature on disability inclusion (DI) in supply and demand chains of hospitality and tourism (H&T) organisations. The purpose of this study is to assess…
Abstract
Purpose
This paper reviews the literature on disability inclusion (DI) in supply and demand chains of hospitality and tourism (H&T) organisations. The purpose of this study is to assess disability support and interventions within H&T organisations. Through the assessment, we identified gaps to recommend H&T scholars’ and practitioners’ knowledge of DI from new perspectives.
Design/methodology/approach
An integrative review was conducted to examine the published evidence on DI in H&T organisations. This study used high-ranking H&T journals from the Scopus and Web of Science databases between 2001 and 2023. In total, 101 empirical papers met the criteria for the review analysis.
Findings
DI focuses heavily on customer disabilities, with scant research on DI in H&T employment. The review emphasises the critical need for empirical research into the varied disability employment ecosystem within H&T organisations, focusing on social integration for inclusive workplaces.
Originality/value
This study contributes to the H&T literature, which previously overlooked the disability context in diversity. The research offers strategies for creating inclusive environments in the H&T industry for disabled consumers and producers.
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Siu Mee Cheng and Cristina Catallo
The Healthy at Home (H@H) is an older adult day program that is in Toronto in Ontario, Canada. This is an integrated health and social care (IHSC) program that seeks to address…
Abstract
Purpose
The Healthy at Home (H@H) is an older adult day program that is in Toronto in Ontario, Canada. This is an integrated health and social care (IHSC) program that seeks to address the social isolation and health needs of a highly vulnerable older adult population living in the north Toronto communities. These are Russian-speaking Jewish older adult immigrants. The case provides a detailed description of the factors that enabled a diverse group of health and social care organizations to integrate their respective services to address the health and social care needs of their clients using a culturally appropriate and trauma-informed lens.
Design/methodology/approach
A case description comprised of key informant interviews, and a focus group was undertaken of representatives from health and social care organizations serving clients in the north Toronto area.
Findings
This case description identified eleven integration factors that enabled organizations to provide integrated care using a culturally appropriate and trauma-informed lens, and they include developing an aligned vision and goals, communications, an inter-organization culture of inter-dependence, champions, pre-existing relationships, and champions. In addition, operating in the not-for-profit sector, sector differences, enabling public policies and a strong sense of community have influenced integration of services across the organizational partners to serve its high-risk client group.
Originality/value
This case description lends insights into how IHSC can be leveraged to provide culturally appropriate and trauma-informed care for highly vulnerable client/patient populations. A lesson learnt is that social care partners can engage in successful integration leadership in joint health and social care integration efforts.
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Weihua Zhang, Yuanchen Zeng, Dongli Song and Zhiwei Wang
The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to…
Abstract
Purpose
The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.
Design/methodology/approach
First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.
Findings
Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.
Originality/value
The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.
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Xinyu Liu, Kun Ma, Ke Ji, Zhenxiang Chen and Bo Yang
Propaganda is a prevalent technique used in social media to intentionally express opinions or actions with the aim of manipulating or deceiving users. Existing methods for…
Abstract
Purpose
Propaganda is a prevalent technique used in social media to intentionally express opinions or actions with the aim of manipulating or deceiving users. Existing methods for propaganda detection primarily focus on capturing language features within its content. However, these methods tend to overlook the information presented within the external news environment from which propaganda news originated and spread. This news environment reflects recent mainstream media opinions and public attention and contains language characteristics of non-propaganda news. Therefore, the authors have proposed a graph-based multi-information integration network with an external news environment (abbreviated as G-MINE) for propaganda detection.
Design/methodology/approach
G-MINE is proposed to comprise four parts: textual information extraction module, external news environment perception module, multi-information integration module and classifier. Specifically, the external news environment perception module and multi-information integration module extract and integrate the popularity and novelty into the textual information and capture the high-order complementary information between them.
Findings
G-MINE achieves state-of-the-art performance on both the TSHP-17, Qprop and the PTC data sets, with an accuracy of 98.24%, 90.59% and 97.44%, respectively.
Originality/value
An external news environment perception module is proposed to capture the popularity and novelty information, and a multi-information integration module is proposed to effectively fuse them with the textual information.
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Guoli Wang and Chenxin Ma
Motivated by the wide application of procurement strategies in retailing, this paper aims to examine the effect of procurement strategies on decisions and profits and strategic…
Abstract
Purpose
Motivated by the wide application of procurement strategies in retailing, this paper aims to examine the effect of procurement strategies on decisions and profits and strategic inventory (SI) is considered.
Design/methodology/approach
The game-theoretic models are developed under a two-period fresh product supply chain (FSC), and consist of the mode of purchasing products only in the first period without SI (Scenario S), the mode of purchasing products in every period without SI (Scenario T) and the mode of purchasing products in every period with SI (Scenario TS).
Findings
Conducting the calculating and comparing, some major findings can be concluded. In general, two-period purchasing strategies (Scenarios T and TS) promote a higher freshness-keeping effort than the single buying strategy (Scenario S). Regarding the pricing strategy, SI and Scenario S can both contribute to obtaining a lower wholesale price, the retailer's pricing is relatively complicated and hinges on the consumer's sensitivity to freshness-keeping effort and the holding cost. Besides, comparing the sales quantity and the profit, the authors find that Scenario TS stimulates more demands and brings more profits for the manufacturer. However, Scenario TS is not the optimal selection for the reason that SI sometimes hurts the retailer and even the whole supply chain. Whereas, when the holding cost is in a certain range, Scenario TS will lead to a win-win situation.
Originality/value
The main findings of this study can give the enterprises some advice on the procurement strategies of fresh products and the decisions of pricing and the freshness-keeping effort.
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Alexander Preko and Hod Anyigba
The aim of this study was to conduct a comprehensive investigation into declining and emerging occupations and job titles and to develop a national career progression pathway for…
Abstract
Purpose
The aim of this study was to conduct a comprehensive investigation into declining and emerging occupations and job titles and to develop a national career progression pathway for the tourism and hospitality (T&H) sector.
Design/methodology/approach
Anchored on the Social Cognitive Career Theory, this study used face to face in-depth interviews of 33 industry stakeholders: policymakers, trade association, training providers and beneficiaries (T&H).
Findings
The finding reveals that only the “watchman” occupation was identified as the declining job while majority of the emerging jobs were more related to information technology and environmental occupations (website designers, digital marketers, data analysts, hygienists, and safety and hazard experts).
Practical implications
The findings provide a valuable signal for the growing number of jobs in security services, hygiene and information technology-oriented occupations, which the Ministry of Tourism, Arts and Culture including practitioners including HR directors and general managers should respond timely to and to these growing needs in order to remain competitive in the sector.
Originality/value
This is the first study in context that responded to a call by industry players to fill in a practical knowledge gap in examining declining and emerging jobs and job titles in the T&H sector. The study provides vocational insights into mapping the entry level requirements for the jobs allied with occupations in the national technical and vocational educational training qualifications framework of Ghana at the national level.
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