Erol Can and Ugur Kilic
Static inverters are very important for the emergency energy distribution system of aircraft and similar machines. At the same time, the electrical energy produced at high…
Abstract
Purpose
Static inverters are very important for the emergency energy distribution system of aircraft and similar machines. At the same time, the electrical energy produced at high frequency for electrical devices is used to reduce the weight of the cables in the aircraft and spacecraft because of the skin effect. In the high-frequency system, a thinner cable cross-section is used, and a great weight reduction occurs in the aircraft. So, fuel economy, less and late wear of the materials (landing gear, etc.) can be obtained with decreasing weight. This paper aims to present the development of a functional multilevel inverter (FMLI) with fractional sinus pulse width modulation (FSPWM) and a reduced number of switches to provide high-frequency and quality electrical energy conversion.
Design/methodology/approach
After the production of FSPWM for FMLI with a reduced component, which, to the best of the authors’ knowledge, is presented for the first time in this study, is explained step by step, and eight operating states are given according to different FSPWMs operating the circuit. The designed inverter and modulation technique are compared by testing the conventional modular multilevel inverter on different loads.
Findings
According to application results, it is seen that there is a 50% reduction in cross-section from 100 Hz to 400 Hz with the skin effect. At 1000 Hz, there is a 90% cross-section reduction. The decrease can be in cable weights that may occur in aircraft from 10 kg to 100 kg according to different frequencies. It causes less harmonic distortion than conventional converters. This supports the safer operation of the system. Compared to the traditional system, the proposed system provides more amplitude in converting the source to alternating voltage and increases the efficiency.
Practical implications
FSPWM is developed for multilevel inverters with reduced components at the high frequency and cascaded switching studies in the power electronics of aircraft.
Social implications
Although the proposed system has less current and power loss as mentioned in the previous sections, it contains fewer power elements than conventional inverters that are equivalent for different hardware levels. This not only reduces the cost of the system but also provides ease of maintenance. To reduce the cable load in aircraft and create more efficient working conditions, 400 Hz alternative voltage is used. The proposed system causes less losses and lower harmonic distortions than traditional systems. This will reduce possible malfunctions and contribute to aircraft reliability for passengers and cargo. As technology develops, it is revealed that the proposed inverter system will be more efficient than traditional inverters when devices operating at frequencies higher than 400 Hz are used. With the proposed inverter, safer operation will be ensured, while there will be less energy loss, less fuel consumption and less carbon emissions to the environment.
Originality/value
The proposed inverter structure shows that it can provide energy transmission for electrical devices in space and aircraft by using the skin effect. It also contains less power elements than the traditional inverters, which are equivalent for different levels of hardware.
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Erol Feyzullahoğlu and Nehir Şakiroğlu
The purpose of this study is to develop new Al‐based bearing alloys which have better properties than classic commercial bearing materials and to analyze tribologic properties of…
Abstract
Purpose
The purpose of this study is to develop new Al‐based bearing alloys which have better properties than classic commercial bearing materials and to analyze tribologic properties of these alloys under dry sliding conditions experimentally.
Design/methodology/approach
Four different aluminium alloys were produced with casting method and tested on pin‐on‐disc wear testing machine. Friction coefficients and weight losses of the samples were determined under various working conditions in consequence of the experiments. Hardness, surface roughness, and surface temperatures of the samples were measured.
Findings
The results of the experiment show that friction coefficients vary by surface pressure and sliding speed. Al15Pb3.7Cu1.5Si1.1Fe and Al15Sn5Cu3Si alloys have lower friction coefficient values than other alloys. Al8.5Si3.5Cu alloy has the biggest wear resistance. Al15Pb3.7Cu1.5Si1.1Fe and Al15Sn5Cu3Si alloys are the most worn materials. Al8.5Si3.5Cu alloy has the lowest wear rate.
Research limitations/implications
When the comparison was done between commercial Al alloys and developed Al alloys in this study, it was seen that Al15Sn5Cu3Si and Al15Pb3.7Cu1.5Si1.1Fe alloys have lower friction coefficient values than other commercial alloys.
Practical implications
The effects of the elements except aluminium composing alloys upon tribologic properties were analyzed. Some of the alloy elements were seen to improve tribologic properties whereas some downgrade. When the results are evaluated, Al15Sn5Cu3Si and Al8.5Si3.5Cu alloys containing Si and Sn can be preferred among the aluminium alloys that will work under dry sliding.
Originality/value
This paper reveals new bearing materials. These alloys can be used in journal bearings.
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İsmail Erol, Meltem Nurtaniş Velioğlu, Funda Sivrikaya Şerifoğlu, Gülçin Büyüközkan, Necati Aras, Nigar Demircan Çakar and Aybek Korugan
This paper aims to examine the current state of reverse supply chain management (RSCM) initiatives in several Turkish industries.
Abstract
Purpose
This paper aims to examine the current state of reverse supply chain management (RSCM) initiatives in several Turkish industries.
Design/methodology/approach
This study is based on an exploratory research regarding RSCM activities of Turkish automotive, white goods, electric/electronics, and furniture industries. The sample consists of all the companies included in the Top‐500 Industrial Enterprises List of The Assembly of the Istanbul Chamber of Industry (ISO).
Findings
The research findings show that the RSCM initiatives in the considered industries are still in a very early stage. Companies' involvement in product returns is mostly due to the legislative liabilities, and system inadequacies are emphasized as the most important reason for not being able to implement an efficient RSCM.
Research implications/limitations
This paper investigates the reverse supply chain practices of selected industries in Turkey and aims to enable researchers to use this study as a building block in understanding these practices and related problems. The limitation of this study is to solely include the medium and large‐sized companies in the industries.
Practical implications
Reverse supply chain operations contribute to the economic sustainability by reducing waste and saving energy and material. In this research, an empirical study in the electronics, white goods, automotive and furniture industries is conducted, and potential research opportunities are discussed to streamline reverse supply chain activities in the industries. Hence, this study can be viewed as an attempt to increase the level of awareness on reverse supply chain issues.
Originality/value
No field study has been conducted to analyze reverse supply chain activities of the industries in Turkey. This research is a pioneering study and will provide a benchmark for the various research activities on related topics.
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Maciel M. Queiroz, Susana Carla Farias Pereira, Renato Telles and Marcio C. Machado
The Industry 4.0 phenomenon is bringing unprecedented disruptions for all traditional business models and hastening the need for a redesign and digitisation of activities. In this…
Abstract
Purpose
The Industry 4.0 phenomenon is bringing unprecedented disruptions for all traditional business models and hastening the need for a redesign and digitisation of activities. In this context, the literature concerning the digital supply chain (DSC) and its capabilities are in the early stages. To bridge this gap, the purpose of this paper is to propose a framework for digital supply chain capabilities (DSCCs).
Design/methodology/approach
This paper uses a narrative literature approach, based on the main Industry 4.0 elements, supply chain and the emerging literature concerning DSC disruptions, to build an integrative framework to shed light on DSCCs.
Findings
The study identifies seven basic capabilities that shape the DSCC framework and six main enabler technologies, derived from 13 propositions.
Research limitations/implications
The proposed framework can bring valuable insights for future research development, although it has not been tested yet.
Practical implications
Managers, practitioners and all involved in the digitalisation phenomenon can utilise the framework as a starting point for other business digitalisation projects.
Originality/value
This study contributes to advancing the DSC literature, providing a well-articulated discussion and a framework regarding the capabilities, as well as 13 propositions that can generate valuable insights for other studies.
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Erol Uzal and Sule Kapkin
The purpose of this paper is to investigate the linear vibrations of an elastic plate subject to irrotational, incompressible fluid flow bounded by a rigid cylinder.
Abstract
Purpose
The purpose of this paper is to investigate the linear vibrations of an elastic plate subject to irrotational, incompressible fluid flow bounded by a rigid cylinder.
Design/methodology/approach
The plate is placed diametrically in the cylinder and extends along it, both infinite in length. The fluid flow is in the axial direction of the cylinder.
Findings
The problem is solved analytically and the eigenfrequencies are obtained explicitly.
Originality/value
The solution offered in this paper allows investigation of the instabilities and computation of the flutter velocity/minimum flow velocity at which the plate vibrations grow in time.
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The global electronic equipment industry has evolved into one of the most innovative technology-based business sectors to transpire in the last three decades. Much of its success…
Abstract
Purpose
The global electronic equipment industry has evolved into one of the most innovative technology-based business sectors to transpire in the last three decades. Much of its success has been attributed to effective supply chain management. The purpose of this paper is to provide an examination of external risk factors associated with the industry’s key suppliers through the creation of Bayesian networks which can be used to benchmark external risks among these suppliers.
Design/methodology/approach
The study sample consists of the suppliers to seven of the leading global electronic equipment companies. Bayesian networks are used as a methodology for examining the supplier external risk profiles of the study sample.
Findings
The results of this study show that Bayesian networks can be effectively used to assist managers in making decisions regarding current and prospective suppliers with respect to their potential impact on supply chains as illustrated through their corresponding external risk profiles.
Research limitations/implications
A limitation to the use of Bayesian networks for modeling external risk profiles is the proper identification of risk events and risk categories that can impact a supply chain.
Practical implications
The methodology used in this study can be adopted by managers to assist them in making decisions regarding current or prospective suppliers vis-à-vis their corresponding external risk profiles.
Originality/value
As part of a comprehensive supplier risk management program, companies along with their suppliers can develop specific strategies and tactics to minimize the effects of supply chain external risk events.
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Sakshi Arora, Divyansha Kumar and Poonam Gulati
This chapter examines the integration of Industry 4.0 (IR 4.0) technologies and sustainability, proposing a people-centric strategy to align industrial progress with environmental…
Abstract
This chapter examines the integration of Industry 4.0 (IR 4.0) technologies and sustainability, proposing a people-centric strategy to align industrial progress with environmental responsibility. Through a synthesis of scholarly insights and practical applications, we delve into the potential of Industry 4.0 to drive economic, social, legal, and environmental sustainability while addressing key challenges and limitations. Acknowledging these obstacles associated with IR 4.0 implementation, including employment displacement and data security risks, we advocate for collaborative efforts among governments, businesses, and society, highlighting the imperative of optimizing the advantages conferred by IR 4.0 while mitigating its adverse effects on sustainability. It calls for strategic investments in education, innovation, and social protection mechanisms to navigate this transition while ensuring equitable and sustainable development for all stakeholders. As these technologies intertwine, it becomes increasingly crucial to establish regulatory frameworks that can endorse the “rule of law” in this ever-evolving legal landscape. Ensuring fairness and effectiveness in regulation is key to navigating this emergent reality. Through fostering synergistic partnerships, embracing sustainable methodologies, and ensuring that the promise of IR 4.0 is realized without sacrificing the fundamental principles of fairness, justice, and human rights, we can envision a future where innovation thrives in harmony with sustainability principles, paving the way for inclusive prosperity.
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Anam Afaq, Loveleen Gaur, Gurmeet Singh, Michal Erben and Alberto Ferraris
This paper aims to explore the role of blockchain (BCT) and Artificial Intelligence (AI) technologies in enhancing and incentivizing environmentally responsible, socially…
Abstract
Purpose
This paper aims to explore the role of blockchain (BCT) and Artificial Intelligence (AI) technologies in enhancing and incentivizing environmentally responsible, socially inclusive and economically viable tourism practices within the hospitality and tourism (H&T) industry.
Design/methodology/approach
This study is based on a critical reflection research approach that enables a synthesis of information derived from existing literature's insights and the authors' experiences and observations. By examining frameworks and theories in the literature, critical reflection also helps develop a more comprehensive understanding of the topic.
Findings
This study portrays how BCT could be used to track the sustainability credentials of tourism providers and how AI can optimize energy usage in hotels. This study depicts how adopting technology-driven sustainable practices in the H&T industry can increase profitability, improve reputation, compliance with regulations, efficiency and a better guest experience.
Practical implications
The study suggests targeted actions and policy frameworks that can be tailored to different stakeholder groups (hospitality businesses, policymakers and tourists) to overcome barriers and maximize the positive societal and environmental impacts of adopting BCT and AI for sustainable tourism.
Originality/value
The originality of this study lies in its ability to offer new perspectives and novel recommendations on the diverse uses of AI and BCT in the context of sustainable tourism. Furthermore, the study provides strategic and policy elements (Targeted actions and policy frameworks) for stakeholders to integrate sustainable tourism practices using BCT and AI successfully. This study differs from earlier review studies that primarily focused on adopting emerging technologies and ignoring the sustainability angle in the use of technology.
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Philip Gerrard and J. Barton Cunningham
Establishes that, in Singapore, which has a minority of Muslims in its population, both Muslims and non‐Muslims are generally unaware of the culture of Islamic banking. Also the…
Abstract
Establishes that, in Singapore, which has a minority of Muslims in its population, both Muslims and non‐Muslims are generally unaware of the culture of Islamic banking. Also the two separate groups have different attitudes towards the Islamic banking movement, with the degree of difference depending on the nature of the respective matter put to them. For example, when asked what they would do if an Islamic bank did not make sufficient profits to make a distribution in any one year, 62.1 per cent of Muslims said they would keep their deposits within the Islamic banking movement, while 66.5 per cent of non‐Muslims said they would withdraw their deposits. In relation to bank selection criteria, there was general accord as between Muslims and non‐Muslims on the rating of the various criteria. Five significant differences were noted, the most relating to “being paid higher interest on savings”. The desire to be paid higher interest was far stronger with non‐Muslims.
Mohammad Faisal, Asif Akhtar and Asad Rehman
India is a home to the second largest Muslim population in the world. It is equally crucial to understand the attitude of non-Muslim population towards the interest-free banking…
Abstract
Purpose
India is a home to the second largest Muslim population in the world. It is equally crucial to understand the attitude of non-Muslim population towards the interest-free banking in India. The firms desirous of entering into this nascent field in India are required to know the aspirations and motivations of both Muslims and non-Muslims with respect to interest-free banking. For a large number of Muslims interest-free banking may be a matter of adhering to their faith, but for the non-Muslim customers it has to address real issues like security, risk minimisation, profitability, etc.
Design/Methodology/Approach
The present study is an attempt to understand the perceptions of Indian customers towards Islamic banking. For this purpose, a representative sample of 259 respondents is surveyed with the help of a structured questionnaire developed for this purpose.
Findings
It has been found that there are differences in the attitude of Muslims and non-Muslims towards Islamic banking. Surprisingly both groups have a similar perception about the institutions of Islamic banking. Findings of the study reveal that the attitude of Indian customers can be classified into factors like awareness, ideology, implementation, features and institutions. Therefore, such factors should be considered seriously by the Islamic banks in designing their marketing strategies.
Research Limitations/Implication
This is a survey-based study. Hence a representative sample is mandatory. Due care has been taken to arrive at a sample size which is representative of the population; however, a large sample size shall lead to better results.
Practical Implications
This study can help decision makers to identify the major factors that may shape the attitude of Indian customers towards Islamic banks. This should also be of some help to the management of commercial banks in devising appropriate marketing strategies for reaching and attracting young customers.
Originality/Value
The originality of this study lies in the fact that it is a pioneering study in the Indian context which brings out the attitudinal differences between Muslims and non-Muslims with respect to Islamic banking. Further, the classification of attitude of Indian customers into factors like awareness, ideology, implementation, features and institutions adds to the originality of the study. Both these aspects of this study add value to the existing literature in the field of Islamic banking.