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The concept of the customer order decoupling point (CODP) has been used in many different contexts as an important structural concept for the traditional forward supply chain. The CODP is rarely explicitly applied in reverse supply chain management and the purpose of this paper is to show that the CODP can be an important corner stone of a framework for analysis of the closed‐loop supply chain containing both forward and reverse material flows.

Conceptual similarities are identified using analogies between forward and reverse supply chains. First, the concepts are discussed in their original context of forward flows and thereafter the concepts are applied on reverse flows. Finally, a holistic closed‐loop model is established.

The conventional CODP framework for forward flow supply chains can be extended to cover also reverse material flows and therefore providing a foundation for a more comprehensive discussion of closed‐loop supply chains useful in both education, research, and industrial applications. Using the suggested extended framework it is possible to identify nine fundamental supply chain configurations.

Differentiating between demand driven and forecast driven activities plays a critical role in practical supply chain management and this paper highlights that this approach also can be applied to closed‐loop supply chains and therefore extending the reach of the toolbox previously developed for the forward supply chain.

The concept CODP has not previously been comprehensively treated for the closed‐loop supply chain and this paper provides a foundation for establishing a strategic structural framework for discussing issues such as lean vs agile and balancing efficiency and responsiveness in a more comprehensive context involving also reverse material flows.

This paper aims to focus on the implementation of the integral back‐stepping control on the model of BILSAT – 1 satellite of the Turkish Scientific and Technological Research Council (TUBITAK).

The nonlinear model of the satellite is divided into three groups and the control Lyapunov function is constructed systematically. The formed closed loop system is analyzed for stability according to a recently developed stability analysis procedure and multi‐run simulations.

Since the studied model includes the dynamics of a practical reaction wheel (SSTL Type: Microwheel), the simulation results showed that the designed controllers are suitable for practical application. The torque requirement is far below the maximum torque supplied by the wheel. In addition, the system seems to be quite fast and robust against the parametric uncertainties.

Since the control system is nonlinear, the computational complexity will be an issue in practical application. The stability analysis should be improved to have more reliable information concerning the disturbance torques. Currently this analysis is performed by multi‐run simulations. An observer or estimator may also be designed in order to compute the attitudes from the gyroscope readings.

The controller designed here can be implemented on the proceeding satellite projects (foregoing BILSAT projects) by TUBITAK.

The paper provides a satellite control application of back‐stepping using a model involving modified Rodriguez parameters and reaction wheel dynamics that is not studied in the literature.

The requirement of robust cooperative control is essential to achieve consensus between unmanned aerial vehicles (UAVs) operating in swarm formation. Often the performance of these swarm formations is affected by wind gust disturbances. This study proposes an effective robust consensus protocol, which will ensure the UAVs in swam formation to collectively meet the desired objective in real-time scenario.

In this work, the swarm of UAVs are modeled as multiagent systems by using the concepts of algebraic graph theory. To address the challenges of a complex and dynamic environment, an adaptive sliding mode control (SMC)-based consensus protocol is proposed. The closed loop stability analysis is established through Lyapunov theory.

The efficacy of the discussed robust consensus controller is analyzed through numerical simulations. Further, the quantitative analysis using Monte-Carlo simulations validates performance of the proposed robust consensus protocol. The presented consensus protocol can be easily implementable as robust flight controller for swarm of UAVs. Also, as the consensus theory is based on the algebraic graph theory, the proposed design is scalable for a large number of UAVs in swarm formation.

The proposed adaptive SMC achieves robust consensus of longitudinal dynamics states between all the UAVs by mitigating the effects of wind gust disturbances. Also, the adaptive SMC offers chattering-free control efforts.

This paper aims to investigate overlaps, complementarities and divergences between the literature on circular economy (CE) models and related literature in non-linear production models and frameworks, including CE, reverse logistics, closed-loop, industrial symbiosis and industrial ecology.

A systematic literature review was conducted focussing on the benefits of non-linear modes adoption.

The results show a high degree of convergence in findings, gaps and weaknesses of these literatures. Negative environmental, economic and operational impacts are understudied. There is a scarcity of studies identifying practices resulting in empirically tested benefits. The business and society case for non-linear production is still largely built upon conceptual studies, modelling and a few case studies. Despite a normative focus, there is very little use of theory, in particular, management theories.

First, the authors use only one, albeit highly recognized database, Scopus. This database may have omitted some relevant research, journals such as the Journal of Cleaner Production and Resources Conservation & Recycling that are more likely to publish such research and also have a more interdisciplinary approach. This is an important gap and interesting result to claim for more interdisciplinary research. Second, the filtering process used and the focus on Association of Business Schools top journals may have also omitted some relevant research, such as a large stream of literature in specialist journals such as Resources Conservation and Recycling and the Journal of Cleaner Production.

There are contradictions, tensions and epistemological ambiguity that needs to be critically addressed. Such tensions may be associated with the knowledge field that gave rise to these different non-linear production approaches. Many of them appeared at the same time, but from different sciences and disciplines with their own perspectives. Then in doing so, they create confusion in the definitions of CE, assumptions underlying modelling and business choices arising from this complexity. This can be minimized through the critical interpretation of knowledge to elucidate epistemological quandaries to improve the understanding of the economic, social and environmental impacts of practices.

In some way, this result makes sense, as the authors have limited the search to management, business and accounts journals, especially talking about Operations Management journals. This is an important gap and interesting result to claim for more interdisciplinary research.

In addition to gaps previously described, the authors identified areas of tensions where the literature offers inconclusive – often contradictory – findings requiring further exploration. A better understanding of these tensions is required to understand the impacts of non-linear production and develop policy guidelines for industry and policymakers to scale-up CE.

The purpose of this paper is analysis of the sensorless control system of induction machine with broken rotor for diagnostic purposes. Increasing popularity of sensorless controlled variable speed drives requires research in area of reliability, range of stable operation, fault symptoms and application of diagnosis methods.

T transformation used for conversion of instantaneous rotor currents electrical circuit representation to space vector components is investigated to apply with closed‐loop modeling algorithm. Evaluation of the algorithm is based on analysis of asymmetry influence to the orthogonal and zero components of space vector representation. Multiscalar model of the machine and selected structures of state observers are used for sensorless control system synthesis. Proposed method of frequency characteristics calculation is used for state observers analysis in open‐loop operation.

New algorithm of applying the T transformation allows for closed‐loop and sensorless control system simulation with asymmetric machine due to broken rotor. Compensating effect of the closed‐loop control system with speed measurements and diagnosis information in control system variables are identified. Proposed frequency analysis of state observers is presented and applied. Variables with amplified characteristic frequency components related to rotor asymmetry are compared for selected structures of state observers and with closed‐loop and open‐loop operation. Method of improving the sensorless system stability is proposed.

In closed‐loop and sensorless control system rotor fault can be diagnosed by using PI output controllers variables. Compensating effect of mechanical variables sets limitation to specified diagnosis methods. Rotor asymmetry affects sensorless control system stability depending on estimator structure.

This paper concentrates upon sensorless control system operation with machine asymmetry and indicates rotor fault symptoms.

The purpose of this article is to evaluate performance of minimum energy controllers thoroughly on a tiltrotor aircraft.

Minimum energy controllers are designed for tiltrotor aircraft models for helicopter and airplane modes. Performance of minimum energy controllers is evaluated with respect to several criteria.

Minimum energy controllers can be used for tiltrotor aircraft flight control system design. These controllers show satisfactory performance when noise intensities and variance bounds vary.

Minimum energy controllers can be implemented for tiltrotor aircraft flight control system design.

In this paper, minimum energy controllers are applied for tiltrotor aircraft flight control system design and the performance of minimum energy controllers is evaluated deeply on a complex physical system (i.e. tiltrotor aircraft).

This study research contributes in fulfilling the gap by carrying out a systematic literature review (SLR) of contemporary research studies in closed-loop supply chain (CLSC). To the best of the author’s knowledge, an SLR rooted in bibliometric analysis has not been carried focusing on advent developments in CLSC. SLR employs scientific methodologies to select papers from standard databases. The SLR using advanced bibliometric and network analysis enables unveiling the key features of the contemporary literature.

The author has analyzed over 333 documents published from 2008 and onward. Using the contemporary tools from bibliometric analysis tools, the author presented an exploratory analysis. A network analysis is utilized to visualize literature and create clusters for the cocited research studies, keywords and publication sources. A detailed multivariate analysis of most influential works published based top 100 articles via a cocitation matrix is done. The multivariate analysis used k-means clustering in which optimal number of clusters are estimated. The analysis is further extended by using a factor analysis, which enables determining the most influential clusters in the k-means clustering analysis.

The SLR using a bibliometric and network analysis enables unveiling the key features of the contemporary literature in CLSC. The author examined published research for influential authors, sources, region, among other key aspects. Network analysis enabled visualizing the clusters of cocited research studies, cowords and publication sources. Cluster analysis of cocited research studies is further explored using k-means clustering. Factor analysis extends findings by identifying most contributing grouping of research areas within CLSC research. Each clustering technique disclosed a unique grouping structure.

CLSC has received considerable attention, and its core areas start with focusing on reverse logistics concepts relating reuse, recycling, remanufacturing, among others. Contemporarily, the studies have enhanced reverse logistics core functionalities interfaced with the other interesting avenues related to CO₂ emission reduction, greening and environmental protection, sustainability, product design and governmental policies. Earlier studies have presented a literature review of CLSC; however, these reviews are commonly conducted in the traditional manner where the authors select papers based on their area of expertise, interest and experience. As such these reviews fall short in utilizing the advanced tools from bibliometric analysis.

This paper presents a systematic literature review of the various aspects of reverse logistics (RL) and closed-loop supply chains (CLSC) in implementing and achieving circular economy (CE) motives. CE is identified as a method of embracing imperishability into the economic structure, helping shift from a linear to a condition leading to ecological and social benefits.

Systematic literature was used to review a total of 80 peer-reviewed articles are included in the study and covers different concepts related to the implementation of CE, such as cost-saving, network design, sustainable RL, waste management and extended producer responsibility.

The findings reveal that the research in the domain is in a growing phase, and in recent years, a lot of attention has been given by researchers across the globe. However, further research is required in crucial areas for the adoption of CE, such as retail reverse logistics, pharmaceutical industries and resource recycling industry.

The study discusses the business needs and solutions for industries. Key enablers and barriers are listed along with the main activities involved in each sector in CLSC. Managers can design a pathway to decide which lever to use to overcome a particular challenge.

The work contributes theoretically by developing research themes in RL and CLSC practices applied to CE. It also provides theoretical and practical implications of the study, which can be used as a signboard for further research.

The purpose of this paper is to present the importance of model accuracy in closed loop control by the help of parallel finite element model of a voltage-fed solenoid with iron core.

The axisymmetric formulation of the domain decomposition-based circuit-coupled finite element method (FEM) is embedded in a closed loop control system. The control parameters for the proportional-integral (PI) controller were estimated using the step response of the analytical, static and dynamic model of the solenoid. The controller measures the error of the output of the model after each time step and controls the applied voltage to reach the steady state as fast as possible.

The results of the closed loop system simulation show why the model accuracy is important in the stage of the controller design. The FEM offers higher accuracy that the analytic model attained with magnetic circuit theory, because the inductance and resistance variation already take into account in the numerical calculation. Furthermore, parallel FEM incorporating domain decomposition to reduce the increased computation time.

A closed loop control with PI controllers is applied for a voltage driven finite element model. The high computation time of the numerical model in the control loop is decreased by the finite element tearing and interconnecting method with direct and iterative solver.

Ovens are semi-industrial multipurpose equipment that are used to provide a desired temperature for specific chemical processes. Temperature regulation in the presence of different type of disturbances and dealing with nonlinear dynamics with large dead time (up to a few minutes) are some undesirable factors that have to be considered in the controller design procedure of the oven systems. Due to these factors, the classical PID controller tuned using Cohen-Coon or Ziegler–Nichol’s tuning methods often fails to meet satisfactory closed-loop performance.

In this paper, to deal with the limitations on the oven system due to the undesirable factors, a hierarchical automaton-guided form controller has been designed. The proposed controller includes several discrete PI controllers, each of which operates locally in the defined operating regions whose separation idea is specific to this paper. Based on the idea proposed in the separation of regions, the controller’s coefficients tuning rules are extracted prior to any determination. Then, a supervisor controller has assumed the task of switching between local controllers. In the next step, by considering a conceptual model for the oven system and using a candidate Lyapunov function, the stability conditions of closed-loop system are discussed and the necessary conditions for the asymptotic stability are derived. The proposed controller is practically implemented with the help of the Arduino Nano platform.

Using several experiments, the superiority of the proposed hierarchical controller in terms of performance and energy consumption has been demonstrated.

The proposed hierarchical controller has been implemented practically and an acceptable closed-loop performance has been achieved. To illustrate the efficiency of the proposed method, the closed-loop stability of this method is shown using the Lyapunov theory.