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To devise a new technique to synthesise optimal feedback control law for non‐linear dynamic systems through fuzzy logic.

The proposed methodology utilizes the open‐loop optimal control solutions (OCSs) of the non‐linear systems for the training of the fuzzy system in the process of developing closed‐loop fuzzy logic guidance (FLG). This is achieved through defining a set of non‐dimensionalised variables related to the system states.

FLG is capable of generating closed‐loop control law for the non‐linear problem investigated. Since the proposed fuzzy structure is independent of the system equations, the approach is potentially applicable to other non‐linear system. Introduction of the non‐dimensional variables in place of the regular states has effectively increased the fuzzy training performance and greatly reduced the number of fuzzy rule bases required to produce accurate solutions for other untrained scenarios.

There exist many complex non‐linear problems in guidance and control of aerospace vehicles. Determination of optimal control laws for such systems is usually a difficult task even in an open‐loop form and in a noise‐free off‐line environment. On the other hand, closed‐loop OCSs are highly desirable for their robust characteristics in actual operating environments, so are more suitable for online applications, but can seldom be realized for complex non‐linear systems. Even though a few researchers have worked in the area of non‐linear optimal control and application of fuzzy logic on such systems, non‐have dealt with closed‐loop optimal fuzzy controllers. This research proposes a new strategy for the determination of optimal feedback control laws for non‐linear systems, which can be utilized in many spacecraft mission applications.

Accepting the assumption that our intelligence depends on the ability to construct models which may allow us to acquire, update and transmit our knowledge, this paper aims to highlight the role of Systems Thinking in developing the “intelligence” of managers for all types and sizes of organization.

Four relevant contributions for improving the “intelligence” of managers will be examined: the ability to understand and model dynamic systems, the structure of Control Systems, the rules of the decision-making process and the identification of systems archetypes.

The paper will show that Systems Thinking, through the logic of Control Systems, offers managers a comprehensive representation of the problem-solving and decision-making processes, teaching them how to distinguish problems from symptoms and to acquire a leverage effect. Additionally, Senge’s system archetypes will be presented and new archetypes will be added to Senge’s list.

The viability of every organization and its effective resilience and survival make it more than ever necessary for managers to adopt Systems Thinking, not only as a technique but also primarily as a discipline for efficient and effective thinking, learning, communication and explanation with regard to the dynamics of the world.

The message of the paper is that by continually applying the rules and language of Systems Thinking, managers develop the capability to continually adapt their models to the dynamics of the world, increase their learning capacity and better gauge their consequent judgments, decisions and behavior, thereby removing the mental impediments to intelligence (inappropriate mental models, defensive routines, judgmental biases, rules, etc.).

The paper aims to investigate how a tablet's design features, namely, its navigation design and visual appearance, influence users' enjoyment, concentration and control, when using tablets for problem-solving, and thereafter how their core flow experiences impact their perceived performance and efficiency with problem-solving.

This study uses a field survey approach to engage 87 participants in a decision sciences class to use eTextbooks and a few other associated educational apps including CourseSmart app for e-notes and highlighting, sketchbook app and a calculator app in tablets to resolve class problems at a large US university.

This study finds that the tablet's interface design features (navigation and visual appearance) make users engrossed in their problem-solving processes with perceived enjoyment, concentration and control. This, in turn, impacts their perceived performance and efficiency. Moreover, visual appearance plays the most significant role in arousing users' affective emotions (i.e. enjoyment), while interface navigation is crucial to engage users' deep concentration (i.e. cognition) and control for problem-solving.

Modern tablets are being used widely in various sectors. More in-depth user flow experience design associated with tablet use for problem-solving contexts should be further advocated in order to provide more engaging and meaningful flow experiences to users.

This study shows that the design of the tablet interface can engage users in problem-solving processes in both affective and cognitive ways. It provides valuable insights on tablet interface design for problem-solving.

The purpose of this paper is to investigate time-optimal control problems for multiple unmanned aerial vehicle (UAV) systems to achieve predefined flying shape.

Two time-optimal protocols are proposed for the situations with or without human control input, respectively. Then, Pontryagin’s minimum principle approach is applied to deal with the time-optimal control problems for UAV systems, where the cost function, the initial and terminal conditions are given in advance. Moreover, necessary conditions are derived to ensure that the given performance index is optimal.

The effectiveness of the obtained time-optimal control protocols is verified by two contrastive numerical simulation examples. Consequently, the proposed protocols can successfully achieve the prescribed flying shape.

This paper proposes a solution to solve the time-optimal control problems for multiple UAV systems to achieve predefined flying shape.

This paper aims to present a unified motion control scheme for quadcopters which not only solves the point stabilization and trajectory tracking problems but also the path following problem.

The control problem is solved based on the kinematic model of the unmanned aerial vehicles (UAV). Next, a dynamic compensation controller is considered through of a quadcopter-inner-loop system to independently track four velocity commands: forward, lateral, up/downward and heading rate. Stability and robustness of the whole control system are proved through the Lyapunov’s method. To evaluate the controller’s performance, a multi-user application which allows bilateral communication between a ground station and the Phantom 3 PRO quadrotor is developed.

The performance of the proposed unified controller is shown through real experiments for the different motion control objectives: point stabilization, trajectory tracking and path following. The experiments confirm the capability of the unified controller to solve different motion problems by an adequate selection of the control references.

This work proposes the design of three types of motion controllers, which can be switched to comply a task in outdoor. Based on the software development kit provided by the company DJI, an application to get and send data to the UAV is developed. By means of this application, the three tasks are tested and the robustness of the controllers is proved.

This paper aims to investigate different multi-objective optimization (MOO) approaches for design and control of electromagnetic devices. The main goal of MOO is to find the set of design variables or control parameters which will provide the best possible values of typical conflicting objective functions.

In the research studies, standard genetic algorithm (GA), non-dominated sorting GA (NSGA-II), migration NSGA algorithm and alternance method of optimal control theory are discussed and compared.

The test practical problems of multi-criteria optimization of induction heating processes with respect to chosen quality criteria confirm the effectiveness of application of considered MOO approaches both for the problems of design and control.

This paper represents and investigates different MOO approaches for design and control of electrotechnological systems.

Distributed control is an effective method for controlling and suppressing excessive vibrations of continuous systems. Optimal distributed control for a plate problem is solved utilizing a maximum principle after the introduction of a quadratic index of performance in terms of displacement, velocity and a control force as well as an adjoint variable. The problem is reduced to solving a system of partial differential equations for the state variable and the adjoint variable subjected to boundary, initial and terminal conditions. A numerical algorithm is presented to solve the optimal distributed control problem in the space‐time domain which reduces the computational effort required to solve the initial‐terminal‐boundary value problem. Results obtained for a simply supported, rectangular, thin plate are also presented.

The purpose of this paper is to define the process of analog circuit optimization on the basis of the control theory application. This approach produces many different strategies of optimization and determines the problem of searching of the best strategy in sense of minimal computer time. The determining of the best strategy of optimization and a searching of possible structure of this strategy with a minimal computer time is a principal aim of this work.

Different kinds of strategies for circuit optimization have been evaluated from the point of view of operations’ number. The generalized methodology for the optimization of analog circuit was formulated by means of the optimum control theory. The main equations for this methodology were elaborated. These equations include the special control functions that are introduced artificially. This approach generalizes the problem and generates an infinite number of different strategies of optimization. A problem of construction of the best algorithm of optimization is defined as a typical problem of the control theory. Numerical results show the possibility of application of this approach for optimization of electronic circuits and demonstrate the efficiency and perspective of the proposed methodology.

Examples show that the better optimization strategies that are appeared in limits of developed approach have a significant time gain with respect to the traditional strategy. The time gain increases when the size and the complexity of the optimized circuit are increasing. An additional acceleration effect was used to improve the properties of presented optimization process.

The obtained results show the perspectives of new approach for circuit optimization. A large set of various strategies of circuit optimization serves as a basis for searching the better strategies with a minimum computer time. The gain in processor time for the best strategy reaches till several thousands in comparison with traditional approach.

The purpose of this paper is to deal with a problem of admission control in computer networks when some of their parameters are uncertain. The case is considered when the most common probabilistic description of the uncertainty cannot be used and another approach should be applied.

The uncertain versions of admission control problem with quality of service requirements are considered. The uncertain variables are used to describe possible values of the unknown parameters in computer networks.

Given are formulations for the admission control problem in computer networks with unknown values of the capacities based on the network utility maximization concept. Solution algorithms for all these problems are proposed.

It is assumed that an expert can describe possible values of uncertain network parameters in the form of a certainty distribution. Then the formalism of uncertain variables is applied and the knowledge of an expert is modelled with the use of certainty distributions. Decisions strongly depends on the quality of an expert's knowledge.

Obtained admission control algorithms can be useful for planning and designing of computer networks.

A new approach to the admission control problem in computer networks in the presence of uncertainty, in the case when the uncertain variable can be applied, is proposed and discussed.

This study aims to investigate the impact of board independence on the cash dividend payments of family firms listed on the Borsa Istanbul (BIST) in balancing controlling families’ power to mitigate agency problems between family and minority shareholders in the post-2012 period. The authors focus on this period because Turkish authorities implemented mandatory regulations on the employment of independent directors on boards from fiscal year 2012.

The research model uses a panel dataset of 153 BIST-listed family firms over the period 2012–2017, employs alternative dependent variables and regression techniques and is applied to various sub-groups to improve robustness.

The empirical results show a strong positive effect of board independence on dividend decisions. The authors further detect that family directorship exhibits a negative effect, whereas both board size and audit committees have positive influences but chief executive officer (CEO)/duality has had no significant impact on the dividend policies of Turkish family firms since the new compulsory legal requirements in the Turkish market.

The findings suggest that independent directorship and dividend policy are complementary governance mechanisms to reduce agency conflicts between families and minority shareholders in Turkey, which is a civil law-based emerging country characterized by high family ownership concentration.

The authors present evidence that Turkish family firms’ corporate boards have evolved, to some extent, from being managerial rubber stamps to more independent boards that raise opposing voices in family decision-making. However, independent directors’ preference for dividend-induced capital market monitoring implies that their direct monitoring is less effective than it is supposed to be. This suggests a need to revise the Turkish Corporate Governance Principles to enhance independent directors’ monitoring and supervisory power.

This is thought to be the first study to provide insights on how board independence influences dividend policy in controlling agency problems in Turkish family firms since Turkish authorities introduced compulsory rules on the employment of independent directors on boards.