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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.

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.

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.

FSPWM is developed for multilevel inverters with reduced components at the high frequency and cascaded switching studies in the power electronics of aircraft.

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.

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.

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.

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.

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.

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.

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.

This paper reveals new bearing materials. These alloys can be used in journal bearings.

This paper aims to examine the current state of reverse supply chain management (RSCM) initiatives in several Turkish industries.

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).

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.

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.

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.

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.

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).

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.

The study identifies seven basic capabilities that shape the DSCC framework and six main enabler technologies, derived from 13 propositions.

The proposed framework can bring valuable insights for future research development, although it has not been tested yet.

Managers, practitioners and all involved in the digitalisation phenomenon can utilise the framework as a starting point for other business digitalisation projects.

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.

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.

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.

The problem is solved analytically and the eigenfrequencies are obtained explicitly.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

The purpose of this study synthesises the body of research revolving around blockchain technology (BCT) whilst drawing on the technology-organization-environment framework, resource-based theory and theory of constraints, to conceptualize capabilities (enablers) and constraints (barriers) of BCT in the hospitality and tourism (H&T) industry.

A systematic literature review of BCT in the hotel and tourism industry has been achieved through two databases, i.e. Scopus and Web of Science. From 544 articles selected between the years 2008 and 2023 (first quarter), a sample of 49 articles was used to structure existing research on this subject.

The findings of this systematic literature review of BCT in the H&T literature establish a solid groundwork for assessing the evolution of this research area over time. Findings are classified into two groups: capabilities (enablers) and constraints (barriers) of BCT based on publication year, different research methods, theoretical underpinnings and applicable contexts.

To the best of the authors’ knowledge, this is one of the first attempts to synthesize studies related to BCT in H&T research by combining three theoretical approaches. It serves as a foundation to evaluate the development of BCT studies in this field.

This paper aims to increase the integrity of the planning process with the executive process by simulating the Last Planner System (LPS) technique using building information modeling.

A five-dimensional model was prepared, and after specifying the number of physical conflicts on the plans, all the scenarios of the starting points in the expert contractors’ plans were analyzed. Accordingly, the best scenario was determined by LPS technique. To assess the performance of the study, it was implemented on several tasks of a construction project.

The results of this research indicate that if this method is used in the planning process, the time conflicts between the expert contractors who are in the critical path are reduced, and the total delay of the scheduled time reaches zero. In addition, the conflicts between contractors whose suspension will cause no incentive and increase the daily cost overruns will reduce to the lowest point.

By simulating LPS in the planning process, time-physical conflicts are considered at the lowest point. Using this approach, conflicts are detected before the execution process, resulting in a significant reduction in the delays and cost overruns in construction projects.