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Article
Publication date: 26 June 2021

Yekta Bakırlıoğlu, Nazlı Terzioğlu, Sine Celik, Ainur Ulan and Jordi Segalas

This paper aims to present key characteristics of educational design briefs for the circular economy (CE) through the analysis of 11 design briefs focussing on real-life…

Abstract

Purpose

This paper aims to present key characteristics of educational design briefs for the circular economy (CE) through the analysis of 11 design briefs focussing on real-life challenges related to sustainability and the CE, developed with collaborating industry partners for four consecutive circular design internships conducted in Ireland, Catalunya, The Netherlands and Sweden.

Design/methodology/approach

These four internships were conducted between September 2017 and June 2019 and each internship lasted three to four months. The supervisors for each internship collaborated with local industry partners genuinely interested in adopting sustainable business practices to develop design briefs focussing on real-life challenges they face. The briefs for each internship were developed further according to the feedback of the interns, industry partners and supervisors of previous internships.

Findings

Five steps of brief making for circular design were identified as reviewing the existing resources, emphasizing the importance of systems thinking, emphasizing the importance of collaboration for the CE, focussing on circularity and communicating expectations. The paper outlines how design briefs changed throughout the consecutive internships according to the different curricula and the characteristics of an educational circular design brief.

Originality/value

For design educators and researchers, the value of this paper lies in presenting the steps for the brief making of educational circular design projects. Additionally, the characteristics of circular design briefs are outlined, discussing their focus and content to act as a guide for design educators.

Details

International Journal of Sustainability in Higher Education, vol. 22 no. 5
Type: Research Article
ISSN: 1467-6370

Keywords

Article
Publication date: 9 April 2020

Ranjan Kumar Mohanty and Sachin Sharma

This paper aims to develop a new high accuracy numerical method based on off-step non-polynomial spline in tension approximations for the solution of Burgers-Fisher and coupled…

Abstract

Purpose

This paper aims to develop a new high accuracy numerical method based on off-step non-polynomial spline in tension approximations for the solution of Burgers-Fisher and coupled nonlinear Burgers’ equations on a graded mesh. The spline method reported here is third order accurate in space and second order accurate in time. The proposed spline method involves only two off-step points and a central point on a graded mesh. The method is two-level implicit in nature and directly derived from the continuity condition of the first order space derivative of the non-polynomial tension spline function. The linear stability analysis of the proposed method has been examined and it is shown that the proposed two-level method is unconditionally stable for a linear model problem. The method is directly applicable to problems in polar systems. To demonstrate the strength and utility of the proposed method, the authors have solved the generalized Burgers-Huxley equation, generalized Burgers-Fisher equation, coupled Burgers-equations and parabolic equation in polar coordinates. The authors show that the proposed method enables us to obtain the high accurate solution for high Reynolds number.

Design/methodology/approach

In this method, the authors use only two-level in time-direction, and at each time-level, the authors use three grid points for the unknown function u(x,t) and two off-step points for the known variable x in spatial direction. The methodology followed in this paper is the construction of a non-polynomial spline function and using its continuity properties to obtain consistency condition, which is third order accurate on a graded mesh and fourth order accurate on a uniform mesh. From this consistency condition, the authors derive the proposed numerical method. The proposed method, when applied to a linear equation is shown to be unconditionally stable. To assess the validity and accuracy, the method is applied to solve several benchmark problems, and numerical results are provided to demonstrate the usefulness of the proposed method.

Findings

The paper provides a third order numerical scheme on a graded mesh and fourth order spline method on a uniform mesh obtained directly from the consistency condition. In earlier methods, consistency conditions were only second order accurate. This brings an edge over other past methods. Also, the method is directly applicable to physical problems involving singular coefficients. So no modification in the method is required at singular points. This saves CPU time and computational costs.

Research limitations/implications

There are no limitations. Obtaining a high accuracy spline method directly from the consistency condition is a new work. Also being an implicit method, this method is unconditionally stable.

Practical implications

Physical problems with singular and non-singular coefficients are directly solved by this method.

Originality/value

The paper develops a new method based on non-polynomial spline approximations of order two in time and three (four) in space, which is original and has lot of value because many benchmark problems of physical significance are solved in this method.

Article
Publication date: 20 February 2023

Erol Kayatas and Murat Celik

Any consensus about the effects of dihedral angle on hover rigidity of rotary-wing unmanned aerial vehicles (RW-UAVs) does not exist in the literature. There are researchers who…

Abstract

Purpose

Any consensus about the effects of dihedral angle on hover rigidity of rotary-wing unmanned aerial vehicles (RW-UAVs) does not exist in the literature. There are researchers who state that the dihedral angle has an effect on flight stability and researchers who claim the opposite. The discord stems from the different approaches of these groups to the concept of “stability,” the fact that they conduct experiments whose measurements are largely influenced by environmental conditions, and the physical assumptions are not similar. On the other hand, there is no study examining the effect of dihedral angle on the maneuverability of drones either. This study aims to analytically reveal the consequences of dihedral angles in RW-UAVs in terms of flight agility and maneuverability.

Design/methodology/approach

Dihedral angle examinations on both hover rigidity and maneuverability are carried out analytically. Equations of motions for a multicopter’s rigid body with a dihedral angle under two different conditions (zero and nonzero dihedral angles) are derived. Numerical simulations are conducted by defining the simulation parameters, and then displacement graphics for the center of mass are interpreted.

Findings

The presence of a dihedral angle makes the multicopter platforms behave like a pendulum, and this pendulum motion affects the disturbance rejection and the planar maneuver capabilities of multicopters. Since deflections can be spread to the orthonormal axes thanks to rotation about a pivot, net deflections of the geometric center may be diminished. Besides, pendulum motion eases the maneuvers with yaw rotations since the required rotation might occur without rotors’ revolution per minute changes.

Practical implications

Proposed dihedral angle implementation may enhance the hover stiffness and maneuverability capabilities of multicopters which, in turn, raise the performance of the drones.

Originality/value

This paper presents the analytical basis for the dihedral angle's effects on flight stability and agility.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 26 October 2018

Tugrul Oktay, Harun Celik and Ilke Turkmen

The purpose of this paper is to examine the success of constrained control on reducing motion blur which occurs as a result of helicopter vibration.

Abstract

Purpose

The purpose of this paper is to examine the success of constrained control on reducing motion blur which occurs as a result of helicopter vibration.

Design/methodology/approach

Constrained controllers are designed to reduce the motion blur on images taken by helicopter. Helicopter vibrations under tight and soft constrained controllers are modeled and added to images to show the performance of controllers on reducing blur.

Findings

The blur caused by vibration can be reduced via constrained control of helicopter.

Research limitations/implications

The motion of camera is modeled and assumed same as the motion of helicopter. In model of exposing image, image noise is neglected, and blur is considered as the only distorting effect on image.

Practical implications

Tighter constrained controllers can be implemented to take higher quality images by helicopters.

Social implications

Recently, aerial vehicles are widely used for aerial photography. Images taken by helicopters mostly suffer from motion blur. Reducing motion blur can provide users to take higher quality images by helicopters.

Originality/value

Helicopter control is performed to reduce motion blur on image for the first time. A control-oriented and physic-based model of helicopter is benefited. Helicopter vibration which causes motion blur is modeled as blur kernel to see the effect of helicopter vibration on taken images. Tight and soft constrained controllers are designed and compared to denote their performance in reducing motion blur. It is proved that images taken by helicopter can be prevented from motion blur by controlling helicopter tightly.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

Book part
Publication date: 24 February 2023

Romina Gómez-Prado, Aldo Alvarez-Risco, Jorge Sánchez-Palomino, Berdy Briggitte Cuya-Velásquez, Sharon Esquerre-Botton, Luigi Leclercq-Machado, Sarahit Castillo-Benancio, Marián Arias-Meza, Micaela Jaramillo-Arévalo, Myreya De-La-Cruz-Diaz, Maria de las Mercedes Anderson-Seminario and Shyla Del-Aguila-Arcentales

In the academic field of business management, several potential theories were established during the last decades to explain companies' decisions, organizational behavior…

Abstract

In the academic field of business management, several potential theories were established during the last decades to explain companies' decisions, organizational behavior, consumer patterns, and internationalization, among others. As a result, businesses and scholars were able to analyze and decide based on theoretical approaches to explain the current conditions of the market. Secondary research was conducted to collect more than 36 management theories. This chapter aims to develop the most famous theories related to business applied in the international field. The novelty of this chapter relies on the compilation of recognized previous research studies from the academic literature and evidence in international business.

Article
Publication date: 12 May 2020

Jing Bai, Yuchang Zhang, Xiansheng Qin, Zhanxi Wang and Chen Zheng

The purpose of this paper is to present a visual detection approach to predict the poses of target objects placed in arbitrary positions before completing the corresponding tasks…

Abstract

Purpose

The purpose of this paper is to present a visual detection approach to predict the poses of target objects placed in arbitrary positions before completing the corresponding tasks in mobile robotic manufacturing systems.

Design/methodology/approach

A hybrid visual detection approach that combines monocular vision and laser ranging is proposed based on an eye-in-hand vision system. The laser displacement sensor is adopted to achieve normal alignment for an arbitrary plane and obtain depth information. The monocular camera measures the two-dimensional image information. In addition, a robot hand-eye relationship calibration method is presented in this paper.

Findings

First, a hybrid visual detection approach for mobile robotic manufacturing systems is proposed. This detection approach is based on an eye-in-hand vision system consisting of one monocular camera and three laser displacement sensors and it can achieve normal alignment for an arbitrary plane and spatial positioning of the workpiece. Second, based on this vision system, a robot hand-eye relationship calibration method is presented and it was successfully applied to a mobile robotic manufacturing system designed by the authors’ team. As a result, the relationship between the workpiece coordinate system and the end-effector coordinate system could be established accurately.

Practical implications

This approach can quickly and accurately establish the relationship between the coordinate system of the workpiece and that of the end-effector. The normal alignment accuracy of the hand-eye vision system was less than 0.5° and the spatial positioning accuracy could reach 0.5 mm.

Originality/value

This approach can achieve normal alignment for arbitrary planes and spatial positioning of the workpiece and it can quickly establish the pose relationship between the workpiece and end-effector coordinate systems. Moreover, the proposed approach can significantly improve the work efficiency, flexibility and intelligence of mobile robotic manufacturing systems.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 7 September 2012

Kezban Çelik and Ayşegül Esin

The purpose of this paper is to explain the sexual and reproductive health needs, barriers to accessing services as well as the expectations of the youth who do not use the…

224

Abstract

Purpose

The purpose of this paper is to explain the sexual and reproductive health needs, barriers to accessing services as well as the expectations of the youth who do not use the services provided by the Youth Counseling and Health Service Centres in Ankara Province, Turkey.

Design/methodology/approach

The study is based on the results of 12 focus group discussions conducted with young people in the 8th (14‐ to 15‐year‐old) and 12th (aged 17‐ to 18‐year‐old) grades who are not service users.

Findings

The findings suggest that gender, socio‐economic level of the family, religion, the condition of the facilities and the visibility of the centres are factors affecting service usage.

Originality/value

The paper analyses factors that affect the use of services, such as male vs female, primary school vs high school, centre vs periphery, and shows how religion, region, gender, education and socio‐economic dimensions have to be taken into account in understanding the sensitivity of sexuality‐related issues among adolescents.

Details

Journal of Children's Services, vol. 7 no. 3
Type: Research Article
ISSN: 1746-6660

Keywords

Article
Publication date: 2 February 2021

Neeraj Dhiman, M.J. Huntul and Mohammad Tamsir

The purpose of this paper is to present a stable and efficient numerical technique based on modified trigonometric cubic B-spline functions for solving the time-fractional…

Abstract

Purpose

The purpose of this paper is to present a stable and efficient numerical technique based on modified trigonometric cubic B-spline functions for solving the time-fractional diffusion equation (TFDE). The TFDE has numerous applications to model many real objects and processes.

Design/methodology/approach

The time-fractional derivative is used in the Caputo sense. A modification is made in trigonometric cubic B-spline (TCB) functions for handling the Dirichlet boundary conditions. The modified TCB functions have been used to discretize the space derivatives. The stability of the technique is also discussed.

Findings

The obtained results are compared with those reported earlier showing that the present technique gives highly accurate results. The stability analysis shows that the method is unconditionally stable. Furthermore, this technique is efficient and requires less storage.

Originality/value

The current work is novel for solving TFDE. This technique is unconditionally stable and gives better results than existing results (Ford et al., 2011; Sayevand et al., 2016; Ghanbari and Atangana, 2020).

Details

Engineering Computations, vol. 38 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 10 July 2019

Khalid Arar, Deniz Örücü and Gülnur Ak Küçükçayır

This chapter presents facets of the current challenges relating to policy, leadership and praxis, as perceived by school principals and both Turkish and Syrian teachers working…

Abstract

This chapter presents facets of the current challenges relating to policy, leadership and praxis, as perceived by school principals and both Turkish and Syrian teachers working with refugee and Turkish students in Syrian refugee schools in Ankara. Adopting a qualitative methodology, we explore the experiences, challenges and strategies of the educators in these new school types. In order to investigate this this phenomenon, we adopted the post-migration ecology framework proposed by Anderson et al. (2004) and the conceptualization of five dimensions of multicultural education (content integration, knowledge construction process, prejudice reduction, equity pedagogy and empowering the culture and organization of the school) developed by Banks and Banks (1995). The relevant policy, despite its focus on full integration, is still developing and lack clear technical guidelines for specific issues at school level. The data revealed three themes: perceptions towards the refugees, policy into practice in the schools and the consequent challenges, strategies and needs. Although humanistic ideals are manifest in all the participants’ experience with the new phenomena of refugee education, their needs are multifaceted. They are motivated by a pedagogy of compassion, containment and humanistic universal commitment. The principals employ a style of encouraging social justice and moral leadership, whereas the teachers practise the multicultural pedagogy dimensions with trial and error. Incorporation of Syrian educators and their experience and assistance to the Turkish school staff is also discussed.

Article
Publication date: 2 October 2018

Tugrul Oktay, Seda Arik, Ilke Turkmen, Metin Uzun and Harun Celik

The aim of this paper is to redesign of morphing unmanned aerial vehicle (UAV) using neural network for simultaneous improvement of roll stability coefficient and maximum…

Abstract

Purpose

The aim of this paper is to redesign of morphing unmanned aerial vehicle (UAV) using neural network for simultaneous improvement of roll stability coefficient and maximum lift/drag ratio.

Design/methodology/approach

Redesign of a morphing our UAV manufactured in Faculty of Aeronautics and Astronautics, Erciyes University is performed with using artificial intelligence techniques. For this purpose, an objective function based on artificial neural network (ANN) is obtained to get optimum values of roll stability coefficient (Clβ) and maximum lift/drag ratio (Emax). The aim here is to save time and obtain satisfactory errors in the optimization process in which the ANN trained with the selected data is used as the objective function. First, dihedral angle (φ) and taper ratio (λ) are selected as input parameters, C*lβ and Emax are selected as output parameters for ANN. Then, ANN is trained with selected input and output data sets. Training of the ANN is possible by adjusting ANN weights. Here, ANN weights are adjusted with artificial bee colony (ABC) algorithm. After adjusting process, the objective function based on ANN is optimized with ABC algorithm to get better Clβ and Emax, i.e. the ABC algorithm is used for two different purposes.

Findings

By using artificial intelligence methods for redesigning of morphing UAV, the objective function consisting of C*lβ and Emax is maximized.

Research limitations/implications

It takes quite a long time for Emax data to be obtained realistically by using the computational fluid dynamics approach.

Practical implications

Neural network incorporation with the optimization method idea is beneficial for improving Clβ and Emax. By using this approach, low cost, time saving and practicality in applications are achieved.

Social implications

This method based on artificial intelligence methods can be useful for better aircraft design and production.

Originality/value

It is creating a novel method in order to redesign of morphing UAV and improving UAV performance.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 8
Type: Research Article
ISSN: 1748-8842

Keywords

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