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Article
Publication date: 5 April 2024

Yiwei 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.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 20 September 2023

John Chung-En Liu and Ting-Yu Kan

This study aims to evaluate the current situation of education for sustainable development, climate change education and environmental education in a nationwide context…

Abstract

Purpose

This study aims to evaluate the current situation of education for sustainable development, climate change education and environmental education in a nationwide context. Methodologically, this study calls for more research to go beyond case studies and take a similar approach to examine university curricula and facilitate cross-country comparisons.

Design/methodology/approach

This paper examines the status of climate and sustainability curricula in Taiwan’s higher education system. Using the course catalog for the 2020–2021 academic year, the authors constructed a unique data set that includes 1,827 courses at 29 major universities in Taiwan. In each institution, the authors search for course titles that include “climate,” “sustainable/sustainability” and “environment/environmental” as keywords and code the courses according to their disciplines.

Findings

The finding highlights the variations across institutional types and subject matters. Public universities have an average of 4.94 related courses per 1,000 students, whereas private universities have only 3.13. In general, the relevant courses are more concentrated in the STEM and bioscience fields. The curricula, however, are seriously constrained by the disciplinary structure and foster few transdisciplinary perspectives.

Originality/value

The authors seek to go beyond case studies and offer one of the most comprehensive curricula samples at the national level. Taiwan adds an important data point, as the current literature focuses heavily on the USA and Europe.

Details

International Journal of Sustainability in Higher Education, vol. 25 no. 2
Type: Research Article
ISSN: 1467-6370

Keywords

Article
Publication date: 5 October 2022

Parvathidevi A. and Naga Satish Kumar Ch

This study aims to assess the efficacy of thermal analysis of concrete slabs by including different insulation materials using ANSYS. Regression equations were proposed to predict…

Abstract

Purpose

This study aims to assess the efficacy of thermal analysis of concrete slabs by including different insulation materials using ANSYS. Regression equations were proposed to predict the thermal conductivity using concrete density. As these simulation and regression analyses are essential tools in designing the thermal insulation concretes with various densities, they sequentially reduce the associated time, effort and cost.

Design/methodology/approach

Two grades of concretes were taken for thermal analysis. They were designed by replacing the natural fine aggregates with thermal insulation aggregates: expanded polystyrene, exfoliated vermiculite and light expanded clay. Density, temperature difference, specific heat capacity, thermal conductivity and time were measured by conducting experiments. This data was used to simulate concrete slabs in ANSYS. Regression analysis was performed to obtain the relation between density and thermal conductivity. Finally, the quality of the predicted regression equations was assessed using root mean square error (RMSE), mean absolute error (MAE), integral absolute error (IAE) and normal efficiency (NE).

Findings

ANSYS analysis on concrete slabs accurately estimates the thermal behavior of concrete, with lesser error value ranges between 0.19 and 7.92%. Further, the developed regression equations proved accurate with lower values of RMSE (0.013 to 0.089), MAE (0.009 to 0.088); IAE (0.216 to 5.828%) and higher values of NE (94.16 to 99.97%).

Originality/value

The thermal analysis accurately simulates the experimental transfer of heat across the concrete slab. Obtained regression equations proved helpful while designing the thermal insulation concrete.

Details

World Journal of Engineering, vol. 21 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 29 March 2024

Esra Keskin, Eunhwa Yang, Harun Tanrıvermiş and Monsurat Ayojimi Salami

The facility management (FM) sector, which is developing rapidly, is making slower progress in Turkey compared to Europe and the USA. This paper aims to research the underlying…

Abstract

Purpose

The facility management (FM) sector, which is developing rapidly, is making slower progress in Turkey compared to Europe and the USA. This paper aims to research the underlying issues leading to FM practices and offer insights into the implications of FM-related policies, especially for large urban transformation projects.

Design/methodology/approach

The study used a mixed-methods research design and collected qualitative data through semi-structured interviews with building/site managers and quantitative data through structured surveys with residents. Forty-nine building/site managers and 660 residents participated in the interview and survey from Turkey’s North Ankara and Dikmen Valley urban transformation projects.

Findings

The FM by residents, performed by the managers selected among homeowners, was preferred to the professional FM in Turkey. Education level, age, homeownership and duration of living in the region were associated with selecting FM practices. Cost also had an important place among the selection criteria, and the standard view from the residents was that professional FM would cause a cost increase. However, interviews with building/site managers in North Ankara and Dikmen Valley Urban Transformation areas revealed that a significant part of the problem resulted from insufficient knowledge and experience in FM.

Research limitations/implications

Within the scope of the research, two urban transformation projects in Ankara Province were selected, and the survey was limited to the North Ankara Entrance Urban Transformation Project and Dikmen Valley Urban Transformation Project areas. Although there is a need to improve the understanding of FM in all facilities, built environments and collective buildings, collective buildings in urban transformation areas due to several constraints, those other identified areas are postponed for future study. In addition, collective buildings located in transformation areas differ from others in discussing the social dimension and the impact of management.

Social implications

Within the scope of the research, two urban transformation projects in Ankara Province were selected, and the survey was limited to the North Ankara Entrance Urban Transformation Project and Dikmen Valley Urban Transformation Project areas. Although there is a need to improve the understanding of FM in all facilities, due to several constraints built environments and collective buildings in urban transformation areas, are postponed for future study. In addition, collective buildings located in transformation areas differ from others in discussing the social dimension and the impact of management.

Originality/value

This study evaluates two different FM approaches: FM by residents and professional FM, implemented in Turkey and identifies the criteria for choosing the FM practice. In addition, both building/site managers and residents evaluate different perspectives on FM. This study is unique because it compares different FM practices in Turkey and the criteria for residents to prefer different FM practices.

Details

Facilities , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0263-2772

Keywords

Article
Publication date: 6 February 2024

Han Wang, Quan Zhang, Zhenquan Fan, Gongcheng Wang, Pengchao Ding and Weidong Wang

To solve the obstacle detection problem in robot autonomous obstacle negotiation, this paper aims to propose an obstacle detection system based on elevation maps for three types…

Abstract

Purpose

To solve the obstacle detection problem in robot autonomous obstacle negotiation, this paper aims to propose an obstacle detection system based on elevation maps for three types of obstacles: positive obstacles, negative obstacles and trench obstacles.

Design/methodology/approach

The system framework includes mapping, ground segmentation, obstacle clustering and obstacle recognition. The positive obstacle detection is realized by calculating its minimum rectangle bounding boxes, which includes convex hull calculation, minimum area rectangle calculation and bounding box generation. The detection of negative obstacles and trench obstacles is implemented on the basis of information absence in the map, including obstacles discovery method and type confirmation method.

Findings

The obstacle detection system has been thoroughly tested in various environments. In the outdoor experiment, with an average speed of 22.2 ms, the system successfully detected obstacles with a 95% success rate, indicating the effectiveness of the detection algorithm. Moreover, the system’s error range for obstacle detection falls between 4% and 6.6%, meeting the necessary requirements for obstacle negotiation in the next stage.

Originality/value

This paper studies how to solve the obstacle detection problem when the robot obstacle negotiation.

Details

Industrial Robot: the international journal of robotics research and application, vol. 51 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 18 April 2024

Zhanghuang Xie, Xiaomei Li, Dian Huang, Andrea Appolloni and Kan Fang

We consider a joint optimization problem of product platform design and scheduling on unrelated additive/subtractive hybrid machines, and seek to find efficient solution…

Abstract

Purpose

We consider a joint optimization problem of product platform design and scheduling on unrelated additive/subtractive hybrid machines, and seek to find efficient solution approaches to solve such problem.

Design/methodology/approach

We propose a mathematical formulation for the problem of simultaneous product platform design and scheduling on unrelated additive/subtractive hybrid machines, and develop a simulated annealing-based hyper-heuristic algorithm with adjustable operator sequence length to solve the problem.

Findings

The simulated annealing-based hyper-heuristic algorithm with adjustable operator sequence length (SAHH-osla) that we proposed can be quite efficient in solving the problem of simultaneous product platform design and scheduling on unrelated additive/subtractive hybrid machines.

Originality/value

To the best of our knowledge, we are one of the first to consider both cost-related and time-related criteria for the problem of simultaneous product platform design and scheduling on unrelated additive/subtractive hybrid machines.

Details

Industrial Management & Data Systems, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 25 April 2024

Metin Uzun

This research study aims to minimize autonomous flight cost and maximize autonomous flight performance of a slung load carrying rotary wing mini unmanned aerial vehicle (i.e. UAV…

Abstract

Purpose

This research study aims to minimize autonomous flight cost and maximize autonomous flight performance of a slung load carrying rotary wing mini unmanned aerial vehicle (i.e. UAV) by stochastically optimizing autonomous flight control system (AFCS) parameters. For minimizing autonomous flight cost and maximizing autonomous flight performance, a stochastic design approach is benefitted over certain parameters (i.e. gains of longitudinal PID controller of a hierarchical autopilot system) meanwhile lower and upper constraints exist on these design parameters.

Design/methodology/approach

A rotary wing mini UAV is produced in drone Laboratory of Iskenderun Technical University. This rotary wing UAV has three blades main rotor, fuselage, landing gear and tail rotor. It is also able to carry slung loads. AFCS variables (i.e. gains of longitudinal PID controller of hierarchical autopilot system) are stochastically optimized to minimize autonomous flight cost capturing rise time, settling time and overshoot during longitudinal flight and to maximize autonomous flight performance. Found outcomes are applied during composing rotary wing mini UAV autonomous flight simulations.

Findings

By using stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads over previously mentioned gains longitudinal PID controller when there are lower and upper constraints on these variables, a high autonomous performance having rotary wing mini UAV is obtained.

Research limitations/implications

Approval of Directorate General of Civil Aviation in Republic of Türkiye is essential for real-time rotary wing mini UAV autonomous flights.

Practical implications

Stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads is properly valuable for recovering autonomous flight performance cost of any rotary wing mini UAV.

Originality/value

Establishing a novel procedure for improving autonomous flight performance cost of a rotary wing mini UAV carrying slung loads and introducing a new process performing stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads meanwhile there exists upper and lower bounds on design variables.

Details

Aircraft Engineering and Aerospace Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 19 March 2024

Diana Irinel Baila, Filippo Sanfilippo, Tom Savu, Filip Górski, Ionut Cristian Radu, Catalin Zaharia, Constantina Anca Parau, Martin Zelenay and Pacurar Razvan

The development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM…

Abstract

Purpose

The development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM) processes, have gained significant attention in recent years. Their accuracy, multi-material capability and application in novel fields, such as implantology, biomedical, aviation and energy industries, underscore the growing importance of these materials. The purpose of this study is oriented toward the application of new advanced materials in stent manufacturing realized by 3D printing technologies.

Design/methodology/approach

The methodology for designing personalized medical devices, implies computed tomography (CT) or magnetic resonance (MR) techniques. By realizing segmentation, reverse engineering and deriving a 3D model of a blood vessel, a subsequent stent design is achieved. The tessellation process and 3D printing methods can then be used to produce these parts. In this context, the SLA technology, in close correlation with the new types of developed resins, has brought significant evolution, as demonstrated through the analyses that are realized in the research presented in this study. This study undertakes a comprehensive approach, establishing experimentally the characteristics of two new types of photopolymerizable resins (both undoped and doped with micro-ceramic powders), remarking their great accuracy for 3D modeling in die-casting techniques, especially in the production process of customized stents.

Findings

A series of analyses were conducted, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, mapping and roughness tests. Additionally, the structural integrity and molecular bonding of these resins were assessed by Fourier-transform infrared spectroscopy–attenuated total reflectance analysis. The research also explored the possibilities of using metallic alloys for producing the stents, comparing the direct manufacturing methods of stents’ struts by SLM technology using Ti6Al4V with stent models made from photopolymerizable resins using SLA. Furthermore, computer-aided engineering (CAE) simulations for two different stent struts were carried out, providing insights into the potential of using these materials and methods for realizing the production of stents.

Originality/value

This study covers advancements in materials and additive manufacturing methods but also approaches the use of CAE analysis, introducing in this way novel elements to the domain of customized stent manufacturing. The emerging applications of these resins, along with metallic alloys and 3D printing technologies, have brought significant contributions to the biomedical domain, as emphasized in this study. This study concludes by highlighting the current challenges and future research directions in the use of photopolymerizable resins and biocompatible metallic alloys, while also emphasizing the integration of artificial intelligence in the design process of customized stents by taking into consideration the 3D printing technologies that are used for producing these stents.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 21 March 2024

Shu-Hua Wu and Edward C.S. Ku

This study aims to analyze how restaurants' collaboration with mobile food delivery applications (MFDAs) affects product development efficiency and argues that technological…

Abstract

Purpose

This study aims to analyze how restaurants' collaboration with mobile food delivery applications (MFDAs) affects product development efficiency and argues that technological capabilities moderate relational ties impact the joint decision-making and development efficiency of restaurant products.

Design/methodology/approach

A product development efficiency model was formulated using a resource-based view and real options theory. In all, 472 samples were collected from restaurants collaborating with MFDAs, and partial least squares structural equation modeling was applied to the proposed model.

Findings

The findings of this study indicate three factors are critical to the product development efficiency between restaurants and MFDAs; restaurants must develop a strong connection with the latter to ensure meals are consistently served promptly. Developers of MFDAs should use artificial intelligence analysis, such as order records of different genders and ages or various consumption attributes, to collaborate with restaurants.

Originality/value

To the best of the authors’ knowledge, this study is one of the few that considers the role of MFDAs as a product strategy for restaurant operations, and the factors the authors found can enhance restaurants’ product development efficiency. Second, as strategic artificial intelligence adaptation changes, collaborating firms and restaurants use such applications for product development to help consumers identify products.

Article
Publication date: 17 April 2024

Nguyen Doanh, Truong Tuan Linh and Thi Tuan Linh Pham

This study uses a comprehensive theoretical framework that combines social cognitive theory and neighborhood effect to investigate the influence of neighborhood effects on…

Abstract

Purpose

This study uses a comprehensive theoretical framework that combines social cognitive theory and neighborhood effect to investigate the influence of neighborhood effects on farmers’ outcome expectations, observational learning and self-efficacy. This study aims is to analyze the mechanisms that underlie the adoption of social media by farmers for knowledge exchange in the agricultural context. Specifically, this research explores the role of neighborhood effects, outcome expectations, observational learning and self-efficacy in shaping farmers’ decision-making process regarding the use of social media platforms for exchanging agricultural knowledge.

Design/methodology/approach

The study data was collected through a sample survey conducted among 570 agricultural households residing in the provinces of Thai Nguyen, Cao Bang, Bac Kan and Phu Tho, located in the northern region of Vietnam. To analyze the data, structural equation modeling was used as the statistical technique of choice.

Findings

The findings of the study indicate a significant influence of neighborhood effects on outcome expectations, observational learning and self-efficacy. These factors, derived from social cognitive theory, also exhibit a positive association with farmers’ adoption of social media for knowledge exchange. Additionally, the study highlights that neighborhood contribute to a favorable adoption of social media among farmers via outcome expectations, observational learning, and self-efficacy.

Research limitations/implications

The study is limited in examining farmers’ social media adoption for agriculture knowledge exchange in Northern mountainous area of Vietnam. This study could be replicated across various regions or nations, providing comparative insights into the adoption of social media among farmers for knowledge exchange.

Practical implications

The study findings suggest practical and innovative means to promote farmers’ social media adoption for agriculture knowledge exchange.

Originality/value

This study presents a pioneering approach by integrating social cognitive theory and neighborhood effect to elucidate the factors influencing farmers’ adoption of social media for the purpose of agriculture knowledge exchange.

Details

VINE Journal of Information and Knowledge Management Systems, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2059-5891

Keywords

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