Osman Nuri Şahin and Mehmet İsmet Can Dede
Mobile robots may perform very critical tasks under difficult operating conditions. Faults encountered during their tasks may cause the task to be interrupted or failed…
Abstract
Purpose
Mobile robots may perform very critical tasks under difficult operating conditions. Faults encountered during their tasks may cause the task to be interrupted or failed completely. In the active fault tolerant control methods, it is very important not only to detect the faults that occur in the robot, but also to isolate these faults to develop a fault recovery strategy that is suitable for that specific type of fault. This study aims to develop a model-based fault detection and isolation method for wheel slippage and motor performance degradation that may occur in wheeled mobile robots.
Design/methodology/approach
In the proposed method, wheel speeds can be estimated via the dynamic model of the mobile robot, which includes a friction model between the wheel and the ground. Four residual signals are obtained from the differences between the estimated states and the measured states of the mobile robot. Mobile robot’s faults are detected by using these signals. Also, two different residual signals are generated from the calculation of the traction forces with two different procedures. These six residual signals are then used to isolate possible wheel slippage and performance degradation in a motor.
Findings
The proposed method for diagnosing wheel slip and performance degradation in motors are tested by moving the robot in various directions. According to the data obtained from the test results, a logic table is created to isolate these two faults from each other. Thanks to the created logic table, slippage in any wheel and performance degradation in any motor can be detected and isolated.
Originality/value
Two different recovery strategies are needed to recover temporary wheel slippage and permanent motor faults. Therefore, it is important to isolate these two faults that create similar symptoms in robot’s general movement. Thanks to the method proposed in this study, it is not only possible to isolate the slipping wheel with respect to the non-slipping wheels or to isolate the faulty motor from the non-faulty ones, but also to isolate these two different fault types from each other.
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Emre Uzunoglu, Mehmet Ismet Can Dede and Gökhan Kiper
In the industry, there is always a demand to shorten the task completion durations to maximize the efficiency of the operation. This work focuses on making use of a special type…
Abstract
Purpose
In the industry, there is always a demand to shorten the task completion durations to maximize the efficiency of the operation. This work focuses on making use of a special type of kinematic redundancy, macro–micro manipulation, to minimize the task completion duration. The purpose of this paper is to develop the most convenient trajectory planner to be integrated with industrial computerized numerical control (CNC) systems to resolve kinematic redundancy for task duration minimization.
Design/methodology/approach
A special type of kinematic redundancy is devised by using two kinematically different mechanisms that have different advantages, which are named as macro and micro mechanisms. In this case, the control design including the trajectory planning should be devised taking into account the distinct advantages of both mechanisms. A new trajectory planning algorithm is designed and used for the constructed planar laser-cutting machine, and some benchmark pieces are cut.
Findings
Offline method has practical limitations for employment in a real case scenario such as assuming infinite jerk limits for each axis motion. This limitation was removed by using an online trajectory generation technique. Experimental test results indicate that the online trajectory planning technique developed for the macro–micro mechanism to shorten the task duration was successful.
Practical implications
Although the new trajectory planning algorithm is implemented for a laser-cutting machine, it can also be used for other manufacturing systems that require higher acceleration and accuracy levels than the conventional machines. The new algorithm is compatible with the commercially available CNC systems.
Originality/value
In this work, a new approach to reducing the task duration for planar machining operations was introduced by making use of macro–micro manipulation concept. The core novelty of the work is devising trajectory planning algorithms to get the most efficiency in terms of acceleration limits from a macro–micro manipulation while making these algorithms deployable to most of the CNC systems.
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Mehmet Dede and Sabri Tosunoglu
The objective of this study is to enhance the usage of teleoperation fields, such as in nuclear site decommissioning or nuclear waste disposal, by designing a stable, dependable…
Abstract
Purpose
The objective of this study is to enhance the usage of teleoperation fields, such as in nuclear site decommissioning or nuclear waste disposal, by designing a stable, dependable and fault‐tolerant teleoperation system in the face of “extraordinary” conditions. These “extraordinary” conditions can be classified as variable time delays in communications lines, usage of different robotic systems, component failures and changes in the system parameters during task execution.
Design/methodology/approach
This paper first gives a review of teleoperation systems developed earlier. Later, fault tolerance is proposed for use in teleoperation systems at the processor, actuator, sub‐system, and system levels. Position/force control algorithms are recommended to address stability issues when there is a loss in communications. Various other controls are also introduced to overcome the instability experienced when there is a time delay in the communications line.
Findings
Finally, this work summarizes the teleoperation system architecture and controller design options in terms of a flowchart to help in the conceptual design of such systems.
Originality/value
The impact of these new designs and algorithms will be to expand the limits and boundaries of teleoperation and a widening of its utilization area. Enhanced operation of these systems will improve system reliability and even encourage their use in more critical and diverse applications.
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The purpose of this study is to enable the planning of construction projects with simultaneous consideration of time, cost and safety risks. It also aims to improve the…
Abstract
Purpose
The purpose of this study is to enable the planning of construction projects with simultaneous consideration of time, cost and safety risks. It also aims to improve the decision-making process by evaluating the effectiveness of the Rao-2 algorithm in solving multi-objective time-cost-safety risk problems. In the end, this model is designed to support project managers in enhancing management approaches by addressing project challenges and constraints more efficiently.
Design/methodology/approach
In this study, the Rao-2 algorithm, along with Grey Wolf Optimization (GWO) and Whale Optimization algorithm (WOA), were improved using the crowding distance-based non-dominated sorting method. Rao-2 was first compared to GWO and WOA. Subsequently, it was compared with well-established algorithms in the literature, including genetic algorithm (GA), particle swarm optimization (PSO) and differential evolution (DE). The C-metric, hypervolume and spread metrics were employed for performance measurement. The performance of the algorithms was evaluated on four case studies consisting of 11, 13, 18 and 25 activities.
Findings
The results revealed that Rao-2 performs better than other algorithms as the number of activities increases, when compared using the Hypervolume, Spread and C-metric measures. In terms of performance measures, the GWO algorithm outperformed Rao-2 in some evaluation metrics for the instance involving 11 activities. However, as the number of activities grew, the Rao-2 method consistently generated higher-quality Pareto fronts and outperformed GWO and WOA in all evaluation metrics. The solutions generated by Rao-2 were also superior to those obtained from GA, PSO and DE in all case studies, further demonstrating the capability of our framework to produce a wide range of optimal solutions with high diversity across different case studies.
Originality/value
This research demonstrates that Rao-2 not only improves solution quality when generating Pareto fronts but also achieves better results with fewer function evaluations compared to GA, PSO and DE. The algorithm's efficiency makes it particularly well-suited for optimizing time, cost and safety risks in large-scale construction projects, which in turn positions Rao-2 as a better choice for such projects by producing superior results compared to other algorithms. By providing high-quality solutions with reduced computational demands, Rao-2 offers a faster and more resource-efficient tool for decision-making, contributing to advancements in both the theory and practice of construction project management.
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Eugenie A. Samier, Eman ElKaleh and Waheed Hammad
This chapter provides a critical and comprehensive review of the internationalisation literature. It starts with a brief discussion of the main factors and features that need to…
Abstract
This chapter provides a critical and comprehensive review of the internationalisation literature. It starts with a brief discussion of the main factors and features that need to be considered when internationalising the educational administration and leadership field. This is followed by a critique of the internationalisation of education and the many challenges that hinder the achievement of proper internationalisation. The third section provides an overview of the internationalisation models and practices in different disciplines such as psychology, sociology and political science, which is followed by a discussion on the internationalisation of education organisations in different countries with some examples from Arab and non-Western countries. The final section presents a critical review of literature on internationalising the curriculum and how culture competency and knowledge acquisition are key factors in achieving effective internationalisation. The chapter concludes with an overview of the book collection and the main ideas and concepts discussed in each chapter.
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Zeynep Fatma Niğdeli, Funda Gençer and İzzet Yüksek
The purpose of the study is to provide a dataset about geometrical constructions of early Ottoman tombs for conservation studies. Thus, a proposal for the restitution phase of the…
Abstract
Purpose
The purpose of the study is to provide a dataset about geometrical constructions of early Ottoman tombs for conservation studies. Thus, a proposal for the restitution phase of the damaged tombs aims to develop.
Design/methodology/approach
The study is composed of four phases. First, the representative plan and section drawings of early Ottoman Tombs were redrawn; second, a geometrical analysis was made, a proposal table was prepared for the restitution of the damaged tombs; and last, this table was applied to tomb examples and restitution drawings are verified with the original situation of the tombs.
Findings
Early Ottoman tombs may be interpreted through geometric shapes, including the square, circle, triangle, octagon, arsin grid and quadrature systems. The arsin grid system provides information about the position of the domes and the height of the drums and windows. Quadrature establishes the highest point of domes and entrances. The proposal table, developed from the obtained results, facilitated the identification of the original elements, including the dome, drum, window and portal. This information is crucial for conducting further studies on restitution.
Originality/value
The abundance and dispersed nature of tomb structures compared to other architectural designs pose challenges in their scholarly examination. The early Ottoman tombs, which experienced an increase in numbers following the Conquest of Istanbul, serve as the initial expressions and embodiments of novel architectural endeavors. Thus, the determination of design ideas of the early Ottoman tombs sheds light on Ottoman architectural practice, which has remained largely unknown and guided the conservation studies of the tombs that have lost their integrity and originality.
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This study aimed to determine the expectations of students from mathematics teachers in the planning phase of lesson study (LS) in mathematics classrooms.
Abstract
Purpose
This study aimed to determine the expectations of students from mathematics teachers in the planning phase of lesson study (LS) in mathematics classrooms.
Design/methodology/approach
This study reported only a part of large-scale action research. The participants were Grade 8 students selected by the convenience sampling method. The data were obtained through open-ended questions. The content analysis method was used to analyze the data.
Findings
Four categories emerged: connection, technology-supported teaching, use of concrete materials, practice, and teacher behavior and teaching style.
Research limitations/implications
This study reveals how students in a different culture and education system, such as Türkiye, want to learn mathematics in the LS process of Japanese origin. It also gives some important clues for applying LS in a different culture.
Practical implications
This study may attract the attention of educational stakeholders who want to implement LS in mathematics classrooms by considering student perspectives.
Social implications
Due to the nature of LS, this study may emphasize teacher–student and teacher–teacher interactions. Thus, it can draw attention to the importance of social learning environments where students take responsibility and interact.
Originality/value
This study emphasizes the importance of listening to student voices in LS. Some ideas about mathematics teaching in Turkey should also be given. Finally, it can provide a good basis for understanding and comparing LS practices in different cultures and understandings.
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Jungsun (Sunny) Kim, Mehmet Erdem, JeoungWoo Byun and Hwayoung Jeong
The purpose of this study is to investigate the perceived importance of soft skills for hotel employees, their willingness to use electronic learning (e‐learning) as a training…
Abstract
Purpose
The purpose of this study is to investigate the perceived importance of soft skills for hotel employees, their willingness to use electronic learning (e‐learning) as a training tool to improve their soft skills, and the impact of hotel employees' individual characteristics (i.e. motivation, self‐efficacy, technology anxiety) on their intentions to use e‐learning across different age groups.
Design/methodology/approach
The sample was randomly selected from hotel employees working at various upscale international chain hotels in South Korea. The data were analyzed using structural equation modeling (SEM) to simultaneously measure the impact of four independent variables on the intention to use e‐learning for both younger and older learners.
Findings
The analysis revealed that responsibility, self‐esteem, sociability, and working with diverse groups were rated more important by younger hotel employees. The results suggest that learners who have higher extrinsic motivations in using e‐learning will be more likely to use e‐learning. However, the other variables (i.e. technology anxiety, self‐efficacy, and intrinsic motivation) did not significantly affect the intention to use e‐learning.
Research limitations/implications
The findings are practical for hotel managers/trainers, because they can focus on external rewards instead of internal rewards to motivate employees to use e‐learning. Age did not have a moderating effect between technology anxiety and the intention to use e‐learning. Since the respondents tend to be younger and have a higher standard of education compared with those of the general population, they may more accurately represent hotel employees at upscale or international chain hotels.
Originality/value
The study proposes a framework to examine the impact of hotel employees' individual characteristics on their intention to use e‐learning. The study also validates some relationships that have shown inconsistent results in previous studies. Future research could employ qualitative studies to investigate underlying dimensions of the variables tested in this study.
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Egem Zağralı Çakır and Aydan Bekar
Transitional periods are important for people, such as birth, marriage and death, are important times when ceremonial meals are prepared and served and certain practices are…
Abstract
Purpose
Transitional periods are important for people, such as birth, marriage and death, are important times when ceremonial meals are prepared and served and certain practices are carried out. These periods and the practices constitute our gastronomic cultural heritage. In order to keep our cultural heritage alive and pass it on to future generations, existing values must first be identified and recorded. For this reason, in this study, gastronomic practices of Mentese's transitional periods were examined within the scope of intangible cultural heritage.
Design/methodology/approach
In this research, data was collected using ethnographic design, which is one of the qualitative research methods, and document analysis, interviews and focus group studies, as well as participant observation techniques and image/audio materials. The sample was determined using snowball sampling, convenience sampling and maximum diversity sampling methods. In the analysis of the data, themes and codes related to gastronomic practices in transitional periods were created and direct quotations were included with a descriptive approach.
Findings
It has been found that traditions are kept more alive in rural areas, while those living in the city centres no longer perform these practices dating back to the ancient times. Participants attribute the main reason for this to the fact that economic conditions are not favourable and that some traditional practices are “unnecessary” today. While wedding meals, which are the main part of the weddings, used to be made by women in the past, they are now mostly made by catering companies.
Research limitations/implications
It was accepted that some of the participants started to give short answers as the duration of the interview increased and that the answers given were limited to what the participants could remember.
Originality/value
This study reveals special day meals and practices, rituals and traditions related to food within the scope of Mentese's culinary culture, which has a very deep-rooted history. In this regard, in addition to making an important contribution to the literature, the study also contributes to the articles about “recording and promoting the culture” mentioned in the Intangible Cultural Heritage convention.