Halit Firat Erdogan, Ayhan Kural and Can Ozsoy
The purpose of this paper is to design a controller for the unmanned aerial vehicle (UAV).
Abstract
Purpose
The purpose of this paper is to design a controller for the unmanned aerial vehicle (UAV).
Design/methodology/approach
In this study, the constrained multivariable multiple-input and multiple-output (MIMO) model predictive controller (MPC) has been designed to control all outputs by manipulating inputs. The aim of the autopilot of UAV is to keep the UAV around trim condition and to track airspeed commands.
Findings
The purpose of using this control method is to decrease the control effort under the certain constraints and deal with interactions between each output and input while tracking airspeed commands.
Originality/value
By using constraint, multivariable (four inputs and seven outputs) MPC unlike the relevant literature in this field, the UAV tracked airspeed commands with minimum control effort dealing with interactions between each input and output under disturbances such as wind.
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Ilker Murat Koc, Semuel Franko and Can Ozsoy
The purpose of this paper is to investigate the stability of a small scale six-degree-of-freedom nonlinear helicopter model at translator velocities and angular displacements…
Abstract
Purpose
The purpose of this paper is to investigate the stability of a small scale six-degree-of-freedom nonlinear helicopter model at translator velocities and angular displacements while it is transiting to hover with different initial conditions.
Design/methodology/approach
In this study, model predictive controller and linear quadratic regulator are designed and compared within each other for the stabilization of the open loop unstable nonlinear helicopter model.
Findings
This study shows that the helicopter is able to reach to the desired target with good robustness, low control effort and small steady-state error under disturbances such as parameter uncertainties, mistuned controller.
Originality/value
The purpose of using model predictive control for three axes of the autopilot is to decrease the control effort and to make the close-loop system insensitive against modeling uncertainties.
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Hakan Ülker, Cemal Baykara and Can Özsoy
A fixed wing unmanned aerial vehicle (FWUAV) is targeted to perform processor in the loop (PIL) simulations for the flight scenarios such as straight and level, level climb, level…
Abstract
Purpose
A fixed wing unmanned aerial vehicle (FWUAV) is targeted to perform processor in the loop (PIL) simulations for the flight scenarios such as straight and level, level climb, level turn, climbing turn and level steady heading sideslip under windy conditions such as steady wind (SW) and wind gust (WG) in a desired and controlled manner.
Design/methodology/approach
The constrained multi-input–multi-output (MIMO) lateral and longitudinal linear models-based model predictive controllers (MPCs) which are proposed in a previous study (Ulker et al., 2017) are tested in the PIL simulations under specified windy conditions. BeagleBone Black Rev C is used as a target hardware or processor in the PIL simulations.
Findings
The results of the PIL simulations show that the MPCs proposed in the previous study can achieve satisfactory performance and flying qualities for the all flight scenarios handled in this paper under windy conditions.
Practical implications
The MPCs proposed in the previous study can be easily implemented in the real world to a low-cost and small-sized board like BeagleBone Black Rev C which is used in this paper.
Originality/value
The proposed MPCs in the previous study which are capable of providing more flexibility in terms of tracking complex trajectories are showed to be able to be implemented to real system by means of PIL simulations under the changeable windy conditions which are difficult for performance tests.
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Hakan Ülker, Cemal Baykara and Can Özsoy
The purpose of the paper is to examine a fixed wing unmanned aerial vehicle (UAV) as it undergoes five flight scenarios under straight and level, level climb, level turn, climbing…
Abstract
Purpose
The purpose of the paper is to examine a fixed wing unmanned aerial vehicle (UAV) as it undergoes five flight scenarios under straight and level, level climb, level turn, climbing turn and level steady heading sideslip conditions in a desired and controlled manner using constrained multi input multi output (MIMO) model predictive controllers (MPCs).
Design/methodology/approach
An MPC strategy based on the lateral and longitudinal linear models is proposed for the flight control design. Simulations are carried out for the nonlinear closed-loop aircraft Simulink model available from the University of Minnesota UAV research group with the implemented MIMO MPCs designed in this paper.
Findings
The results of the simulations show that the MIMO MPCs can achieve satisfactory performance and flying qualities under three different test conditions in terms of existing unmeasured outputs and unmeasured output disturbances.
Practical Implications
The MPCs designed in this paper can be implemented to UAVs. Therefore, the implementation is considered as an advanced research.
Originality/value
The proposed MPC design in this paper provides more flexibility in terms of tracking complex trajectories comparing with the classical controllers in the literature. Besides they provide to change more than one reference of the states at any time.
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Beyza Oba, Zeynep Ozsoy and Serap Atakan
The purpose of this study is to understand the power dynamics of the boards of directors in family‐owned and listed Turkish companies. Power and dominance in the boardroom can be…
Abstract
Purpose
The purpose of this study is to understand the power dynamics of the boards of directors in family‐owned and listed Turkish companies. Power and dominance in the boardroom can be studied in relation to three variables: the institutional environment in which the firm is embedded; the structural configurations of the board; and the top manager's propensity to exercise his/her power resources. Focusing on the board level, this paper aims to conceptualize power dynamics as being composed of structural attributes, roles assumed, responsibilities, dependency and representation.
Design/methodology/approach
The research domain of this exploratory study is family‐owned and listed companies operating on the Istanbul Stock Exchange (ISE). The data for the study were collected from three different sources: a survey administered to members of the boards of directors; discourse analysis of corporate governance compliance reports of the same companies; and in‐depth interviews conducted with board members.
Findings
This study shows that on a typical board of directors of a family‐owned and listed Turkish company, the interests of owners and managers are aligned and other stakeholders are not represented; the role of the board is confined to visibility and legitimacy and does not include control.
Originality/value
This paper argues that theories developed for Anglo‐Saxon equity‐market based business systems have limited exploratory power for an emerging economy – namely Turkey – that is based on a business system characterized by close co‐operation between the state, family‐owned businesses and financial markets.
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Celâl Ada and Ayhan Kural
The purpose of this paper is to present the autopilot design for the missile under various disturbances.
Abstract
Purpose
The purpose of this paper is to present the autopilot design for the missile under various disturbances.
Design/methodology/approach
In this study, model predictive control (MPC) method has been used for autopilot design for each axis. The aim of autopilot is that to keep the roll angle value around the zero degree and to track pitch/yaw acceleration commands. This three-axes control methodology also takes into consideration the interaction between pitch, yaw and roll motions.
Findings
The purpose of using MPC method for three-axes of the autopilot is to decrease the control effort and to make the close-loop system insensitive against modeling uncertainties and stochastic effects.
Originality/value
This study shows that the missile is able to reach to the desired target with good robustness, low control effort and little miss-distance under disturbances such as aerodynamic uncertainties, thrust misalignment and gust affect by using this alternative control method.
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Hatice Sadikoglu Asan and Ahsen Ozsoy
Housing quality is determined by both objective and subjective dynamics. This research was conducted to explore the importance of users’ memory as a tool for assessing housing…
Abstract
Purpose
Housing quality is determined by both objective and subjective dynamics. This research was conducted to explore the importance of users’ memory as a tool for assessing housing quality. While objective features of the surroundings generally require physical measurements, subjective features can be supported by residents’ memories. Memory studies can therefore be used as a research tool to understand the housing environment as they provide important references to the past, present, and future. The purpose of this paper is to explore the relationship between users’ (residents) memory and housing quality.
Design/methodology/approach
The methodology comprised a literature review of spatial quality studies and a field study of a modern housing estate in Istanbul. For the field study, housing quality was examined through the memories of residents in the neighbourhood, buildings, and units. With the research, site observations were made, a questionnaire was issued to residents, and in-depth interviews were conducted with residents who had lived there the longest. New dimensions of housing quality problems were then discussed in the conclusion with reference to residents’ memories.
Findings
Memory studies can be used as a research tool to understand the housing environment, as they provide important references to the past, present and future. In the conclusion, new dimensions of the housing quality problems were discussed with the help of the residents’ memories. It was seen that different dimensions of housing quality can be revealed with the help of user memory.
Research limitations/implications
In all, 40 of the total residents (101) accepted to make questionnaires. In-depth interviews were conducted with three long-term residents that are the only ones still alive and had lived the area since the beginning of the life after construction.
Originality/value
With the aim of developing new tools and methods to analyse housing quality, this research presents a new perspective by utilising users’ memories to evaluate spatial quality.
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Zeynep Özsoy and Mustafa Şenyücel
Co-working has become popular among knowledge workers and independent contractors as a means of devising alternative ways of work. Accordingly, women cooperatives, which have…
Abstract
Co-working has become popular among knowledge workers and independent contractors as a means of devising alternative ways of work. Accordingly, women cooperatives, which have prioritized the development of socio-economic conditions of women, have started providing workspaces for their members. Thus, to illustrate how solidarity-based women cooperatives provide alternative co-working solutions, we developed a multi-case study. Our work includes three cooperatives from the city of Istanbul, Türkiye.
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Edmond Manahasa, Ahsen Özsoy and Odeta Manahasa
The proposed definitional framework can be used to define housing typologies of cities in developing countries. It aims to define housing typologies in the capital city of…
Abstract
Purpose
The proposed definitional framework can be used to define housing typologies of cities in developing countries. It aims to define housing typologies in the capital city of Albania, Tirana, using the proposed hierarchical framework within the dynamics of four political periods: Ottoman, establishment, socialist and postsocialist.
Design/methodology/approach
This study proposes a new definitional approach for the housing typologies through a hierarchical framework that defines the typologies based on their political period and legality statuses departing from the case of Tirana, which is featured by a heterogeneous context. Such context is characterized by uncontrollable urban development, making typology definition problematic. Furthermore, beyond the form, spatial and functional features, it presents their exterior distinctiveness as an innovative element. The methodology used in the study includes archival research, image documentation, spatial, functional and exterior distinctiveness analysis of housing typologies and exploration of housing form features in different political periods.
Findings
The study identifies urban formal housing typologies in Tirana detached houses, apartments, mass housing, social housing, gated communities, informal detached houses and housing with in/formal additions.
Originality/value
This definitional approach can be used to define housing typologies for cities featured by heterogeneous urban context.
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Cyberloafing has emerged as a significant phenomenon in the modern workplace, largely driven by shifts in work dynamics. Recent discussions suggest that Dark Triad traits may play…
Abstract
Purpose
Cyberloafing has emerged as a significant phenomenon in the modern workplace, largely driven by shifts in work dynamics. Recent discussions suggest that Dark Triad traits may play a critical role in influencing cyberloafing behaviors; however, research exploring these traits in the context of cyberloafing remains limited. The purpose of this paper is to investigate the complex relationship between the Dark Triad personality traits – psychopathy, Machiavellianism and narcissism – and cyberloafing. Additionally, this study examines four other psychological variables and two demographic factors as potential correlates of cyberloafing.
Design/methodology/approach
The survey sample consisted of 155 working adults from the USA who participated via Amazon’s Mechanical Turk (MTurk). All participants were required to be full-time employees (working 35 or more hours per week) and hold MTurk Master qualifications.
Findings
The findings of this study provide credible support for the research hypotheses. While not all Dark Triad traits are linked to cyberloafing, the influence of certain traits is significant enough to draw meaningful conclusions. Specifically, the results of this study showed that Machiavellianism and psychopathy were associated with both forms of cyberloafing: browsing activities and emailing activities. However, narcissism was not related to any form of cyberloafing. Additionally, pay satisfaction and social media addiction were positively related to both forms of cyberloafing, while age was negatively related.
Research limitations/implications
This paper addresses several limitations, suggests avenues for future research and outlines practical implications for organizations aiming to mitigate the adverse effects of cyberloafing.
Originality/value
Cyberloafing – engaging in non-work-related online activities during work hours – has gained increasing attention because of its potential to disrupt productivity and organizational functioning. However, limited research has explored this important behavior in depth. Building on contemporary studies, this study investigates the underlying mechanisms and potential implications of how Dark Triad traits may either encourage or mitigate cyberloafing.