Supervisory Design Research Articles

SBE configurator: A model generation tool for synthesis of ship lock supervisors

A large number of ship locks in the Netherlands require renovation. This paper focuses on the application of the synthesis-based engineering (SBE) in the design of supervisory controllers for ship locks, to achieve correct-by-construction control software. A configurator for SBE models for supervisor synthesis is proposed, based on parameters describing the mechanical composition. The accompanying tool, which supports model simulation, demonstrates improvement in time, quality and human error avoidance, and is already being used in the design of ship lock supervisors in Lelystad and Maasbracht. The tool was designed for ship locks but the structure of the tool allows adaptation for other families of systems.

Design of Supervisors for Partially Observed Discrete Event Systems Using Quiescent Information

Design of Supervisors for Partially Observed Discrete Event Systems Using Quiescent Information

Design of Optimal Supervisors for the Enforcement of Nonlinear Constraints on Petri Nets

This paper proposes an iterative approach to separate a set of admissible markings of a nonlinear constraint into a number of subsets. At each iteration, we find a maximal subset of admissible markings that are separated from inadmissible markings by linear constraints. Then, the union of all the obtained subsets constitutes the set of all admissible markings. For each subset of admissible markings, we obtain a set of conjunctive linear constraints. Accordingly, we can equivalently transform a given nonlinear constraint to be a set of disjunctive/conjunctive linear constraints, which can deal with the case that both admissible and inadmissible marking spaces of a nonlinear constraint cannot be separated by linear constraints from each other. Furthermore, we propose a method to design a Petri net supervisor for a derived set of disjunctive/conjunctive constraints. Some examples are used to demonstrate the proposed approach. Note to Practitioners—Linear constraints on Petri nets have been widely studied in the literature. However, not all control specifications can be represented as linear constraints. This paper proposes to enforce nonlinear constraints on Petri nets. A maximally permissive supervisor is designed to make the controlled net live with all admissible markings with respect to a given nonlinear constraint. Meanwhile, the structural complexity is also considered by compressing the number of control places in the supervisor. Experimental results show that the proposed approach can implement the control specifications represented by nonlinear constraints.

Modular Supervisory Control for the Coordination of a Manufacturing Cell with Observable Faults

In the present paper, a manufacturing cell in the presence of faults, coming from the devices of the process, is considered. The modular modeling of the subsystems of the cell is accomplished using of appropriate finite deterministic automata. The desired functionality of the cell as well as appropriate safety specifications are formulated as eleven desired languages. The desired languages are expressed as regular expressions in analytic forms. The languages are realized in the form of appropriate general type supervisor forms. Using these forms, a modular supervisory design scheme is accomplished providing satisfactory performance in the presence of faults as well guaranteeing the safety requirements. The aim of the present supervisor control scheme is to achieve tolerance of basic characteristics of the process coordination to upper-level faults, despite the presence of low-level faults in the devices of the process. The complexity of the supervisor scheme is computed.

Legal Policy of Anti-Corruption Supervisor Design: A New Anti-Corruption Model in Indonesia

<p>Corruption is a fact of life in Indonesia and has a significant negative impact. The malicious intention of corruption in Indonesia has normatively shifted in terms of its meaning, adjusting to its opportunity. However, the increase in corruption in Indonesia is not accompanied by a legal policy of anti-corruption supervisor design. This study analyzes the legal procedure of strengthening supervision for corruption prevention in realizing good governance. The results indicate that the derived meaning of malicious intention of corruption in the old order, new order, and reform era gradually reduces the significance of adversarial nature from the perspective of public morality and the state's ideology. The Corruption Eradication Commission has been given authority to prevent and prosecute criminal acts of corruption. Establishing anti-corruption institutions in the regions serves as an anti-corruption enforcement agency and a control and monitoring system for government administration in all agencies to achieve good governance.</p>

Supervisor Design for a Pressurized Reactor Unit in the Presence of Sensor and Actuator Faults

The preservation of the efficient functionality of a pressurized reactor unit in the presence of faults is the aim of the present paper. To satisfy this aim, a distributed supervisory control scheme, considering the possibility of system faults, was designed. Towards this aim, the models of the subsystems of the total pressurized reactor unit in the presence of sensor and actuator faults are developed, using finite deterministic automata. This is the first contribution of the paper. The desired performance of the unit was formulated in the form of rules guaranteeing the desired behavior of a pressurize–depressurize cycle and safety specifications. The rules were translated to six desired regular languages. The realization of these languages, in the form of supervisor automata, was accomplished. This is the second contribution of the paper. A modular supervisory design scheme, towards safety and tolerance in the presence of faults, was proposed and realized, and the properties of the proposed supervisors and the controlled automaton were proven. This is the third contribution of the paper. The complexity of each supervisor was computed. The efficiency of the supervisory design scheme was illustrated through simulations. A PLC implementation of the derived supervisors was proposed. The derived supervisors are suitable for implementation as function blocks.

Implementation of Facility Management to develop Education Quality

The success of educational programs in schools is strongly influenced by the condition of educational facilities and infrastructure. Fulfilling the need for infrastructure facilities aims to describe and analyze planning, organizing, mobilizing, monitoring, as well as supporting and inhibiting factors for infrastructure management to develop the quality of education at RA Nurul Iman Majalengka. Qualitative research data collection techniques by means of observation, interviews, documentation and triangulation. Data analysis techniques: data collection, data reduction, data presentation and drawing conclusions. The findings of this research are planning with annual meetings, evaluating, reviewing work programs, implementing program activities and socializing the program to parents. Organizing: organizational structure, staffing, job descriptions and responsibilities, communication and coordination. Movement by procuring goods, inventory, maintenance, selection, reporting. Supervision by conducting evaluation and supervision as well as follow-up from supervision. Supporting factors: good design, employee placement, neat filing and involvement of madrasa supervisors. Inhibiting factors: the commitment of each human resource, lack of funds, complicated regulations and lack of employee skills development.

Design of supervisors for linear marking specifications in labeled Petri nets

In this paper we study the problem of enforcing a generalized mutual exclusion constraint (GMEC) in a labeled Petri net that contains indistinguishable transitions by a monitor-based supervisor. We show that a monitor-based supervisor can be designed based on the influence of events if the GMEC is deterministic. On the other hand, for a nondeterministic GMEC, we introduce the notion of dependency of transitions, which provides a quantitative relation between the transition firings and the occurrence of dependent events. Based on the dependency of transitions, we propose a structural approach to compute a monitor function using Hilbert basis, which helps us develop an algorithm to design an online supervisor using the monitor function. Our approach has low online computational load since marking estimation is avoided.

Application of the PCF calculus for solving the problem of nonblocking supervisory control of discrete event systems

The paper provides a general view on the original logical inference based approach to dealing with discrete event systems as subject to supervisory control theory. The approach suggests a representation of discrete event system as a positively constructed formula to imply automated logical inference in the calculus of positively constructed formulas. During the inference, languages of the discrete event system are generated and analyzed. The minimally restricting supervisor for uncontrollable specification may be also designed. A nonblocking supervisor design is illustrated with a simplified model of autonomous underwater vehicle operational modes switching.

Pelaksanaan Fungsi Pengawasan Pada Kampanye Pemilihan Kepala Daerah

This paper examines the supervisory function of Election Supervisory Board (Bawaslu) in the 2018 West Kalimantan Governor and Vice Governor election, particularly in campaign administration. The campaign period in electoral cycle is one of the key stages in political contestation that it is vulnerable to malpractices, moreover it involves many parties and masses. The campaign malpractices that often occur are administrative irregularities, involvement of civil servants, and money politics. This paper employed a descriptive qualitative method by using data that were collected through interview and document study during the period October - December 2019. The results of this research revealed that in carrying out the supervisory function, the West Kalimantan Election Supervisory Board carried out malpractices prevention and enforcement which synergize with supervision of the district/city to sub-district/village levels. By emphasizing on the prevention function, the West Kalimantan Election Supervisory Board arranged supervisory design built upon potential vulnerability, which based on sub-stages and regions, conducted socialization intensively in the community, and coordinated with the stakeholders. Meanwhile, in the enforcement function, the West Kalimantan Election Supervisory Board cooperated with General Election Commissions (KPU), police and prosecutors.

Supervisor synthesis and throughput optimization of partially-controllable manufacturing systems

One of the challenges in the design of supervisors with optimal throughput for manufacturing systems is the presence of behavior outside the control of the supervisor. Uncontrollable behavior is typically encountered in the presence of (user) inputs, external disturbances, and exceptional behavior. This paper introduces an approach for the modeling and synthesis of a throughput-optimal supervisor for manufacturing systems with partially-controllable behavior on two abstraction levels. Extended finite automata are used to model the high abstraction level in terms of system activities, where uncontrollability is modeled by the presence of uncontrollable activities. In the lower abstraction level, activities are modeled as directed acyclic graphs that define the constituent actions and dependencies between them. System feedback from the lower abstraction level, including timing, is captured using variables in the extended finite automata of the higher abstraction level. For throughput optimization, game-theoretic methods are employed on the state space of the synthesized supervisor to determine a guarantee to the lower-bound system performance. This result is also used in a new method to automatically compute a throughput-optimal controller that is robust to the uncontrollable behavior.

Deadlock-free Supervisor Design for Robotic Manufacturing Cells With Uncontrollable and Unobservable Events

In this paper, a deadlock prevention policy for robotic manufacturing cells with uncontrollable and unobservable events is proposed based on a Petri net formalism. First, a Petri net for the deadlock control of such systems is defined. Its admissible markings and first-met inadmissible markings (FIMs) are introduced. Next, place invariants are designed via an integer linear program (ILP) to survive all admissible markings and prohibit all FIMs, keeping the underlying system from reaching deadlocks, livelocks, bad markings, and the markings that may evolve into them by firing uncontrollable transitions. ILP also ensures that the obtained deadlock-free supervisor does not observe any unobservable transition. In addition, the supervisor is guaranteed to be admissible and structurally minimal in terms of both control places and added arcs. The condition under which the supervisor is maximally permissive in behavior is given. Finally, experimental results with the proposed method and existing ones are given to show its effectiveness.

Design of Supervisors for Active Diagnosis in Discrete Event Systems

In this article, we present an active diagnosis method to enhance diagnosability of a plant modeled by a finite-state automaton. Some properties of active diagnosis and silent blocking are studied. To avoid silent blocking, the notion of $stop$ -free event set is proposed, and a $stop$ -free control policy that does not introduce silent blocking is formulated. We develop a heuristic method based on the verifier of the plant to compute a feasible $stop$ -free event set that guarantees the existence of a valid control policy. With the $stop$ -free event set, the set of disabled edges is computed, and an online control policy that is based on the current diagnostic state is computed, which guarantees that the closed-loop system is diagnosable. The structural complexity of the proposed control structure is polynomial with respect to the number of states of the plant.

Lethargic Research Projects: Student-supervisor’s Dilemmas in Managing Research Projects

Starting an academic research project is an exciting journey which students approach with high zeal, excitement and passion. Eventually, the excitement reduces; very few complete on time, a sizable number abandon their studies and others drag on for long beyond the allowable academic time. In fact, most of the students end up applying for extension of time before they are deregistered. On estimate, only 10% of those who begin their PhD journey are able to complete in an average 4 years’ time. This paper analyzed the dilemmas students go through in their research process and the challenges supervisors meet in handling doctoral research projects. The study employed an exploratory design. Self-administered questionnaires were used on 42 respondents who included; PhD students on a research project, PhD student supervisors and PhD holders who had undertaken a research project. Data analysis was done concurrently with data gathering using content analysis method. The study findings indicated that supervisor challenges are mainly institutional constructed, while students recounted lack of clear guidance and orientation on the research process, attributed to both the institution and supervisor. Mutually, there is a tendency to assume that both parties have a clear familiarity with the study process. The study recommends the need for attention in; planning, design and orientation of both students and supervisors in managing academic research projects specifically, outlining expected milestones at each level. The study designed a triad supervisory model that can be adopted by institutions of higher learning in Africa to improve graduate rates, solve the student-supervisor challenges and improve PhD quality of research.

Robust supervisory control of discrete event systems against intermittent loss of observations

We address in this paper the design of robust supervisors that are able to cope with intermittent loss of observations and also make the controlled system achieve the specification language under nominal operation. In order to do so, we introduce a definition of robust observability that leverages possible observations of the events that are subject to intermittent loss of observations and address language permissiveness by extending the recently introduced definition of relative observability to robust relative observability. We present necessary and sufficient conditions for the existence of robust supervisors that make the controlled system achieve robustly controllable and observable or relatively observable languages and present a characterisation of all achievable languages. A running example illustrates all the results presented in the paper, and an example taken from the open literature is used to illustrate the efficiency of the robust design strategy proposed in the paper.

Structural Liveness Analysis of Automated Manufacturing Systems Modeled by S4PRs

This paper presents a liveness analysis method for sequential automated manufacturing systems (AMSs), which can be modeled by a class of Petri nets named systems of sequential systems with shared resources (S4PR). We show that deadlocks in S4PR can be characterized by the saturation of its structural object named a perfect activity circuit (PA-circuits). Thus, S4PR is live if and only if no PA-circuits in it is saturated at all reachable states. A PA-circuits of an S4PR may not be saturated at any state; hence, we propose an integer linear program (ILP) to determine whether a PA-circuits can be saturated or not. Then an algorithm is proposed to compute the set of PA-circuits that may be saturated. This presented method nontrivially generalizes deadlock characterization and liveness condition of ordinary Petri nets to a broader class of nonordinary ones. Note to Practitioners —In the context of AMS, liveness is the most important property since it implies that there is no partial deadlock during the system evolution, and hence, all part types can be produced smoothly. We study the problem of liveness for AMS with the most general resource allocation and flexible routing, which can be modeled by S4PRs or disjunctive/conjunctive (D/C) resource allocation systems (RASs). Given such a complex AMS, based on its Petri net model, this paper presents a sufficient and necessary liveness condition by utilizing the structural properties, and develops an algorithm to identify all the structural objects that may lead the systems to deadlocks. This paper is significant in liveness-enforcing supervisor design for S4PR.

Employee Overqualification: Advancing Supervisor, Career, and Research Design Perspectives

Employee overqualification has received an increasing level of research attention. However, there is ambiguity pertaining to the desirability of an overqualified workforce. In order to better under...

Supervision Strategy to Mitigate the Effect of Electric Vehicles (EVs) Charging Load on Power Distribution System Operations

In a fast charging station (FCS) electrical energy is supplied to rapidly charge electric vehicles (EVs). EV charging station acts as the load of the power distribution system, and the large-sized charging activity may bring an effect on the power distribution system. In this paper, an approach to forecast the characteristic of power consumption due to EVs charging has been studied by using Monte Carlo and Artificial Neural Network (ANN) method. The traveling distance of EV users, the state of charge (SOC) of EV battery, and the arrival time to the FCS have been considered in this study. The proposed mathematical equation has been used to determine the number of FCS in the area. Finally, a Fuzzy supervisor design methodology has been applied to model supervision strategy in order to reduce the effect on the power distribution system by considering the electric energy demand of EV and number of EV to be charged. Thus, the obtained results indicate that the effect of EVs charging on the power distribution system increases voltage fluctuation and power losses. A supervision strategy can mitigate the effect of EVs charging on the power distribution system.

Using social network analysis and gradient boosting to develop a soccer win–lose prediction model

We present the conceptual framework of a soccer win–lose prediction system (SWLPS) focused on passing distribution data (which is a representative characteristic of soccer) using social network analysis (SNA) and gradient boosting (GB). The general purpose of soccer predictions is to help the field supervisor design a strategy to win subsequent games using the derived information to improve and expand the coaching process. To implement and evaluate the proposed SWLPS, actual network indicators and predicted network indicators are generated using passing distribution data and SNA. The win–lose prediction is conducted using the GB machine learning technique. The performance of the SWLPS is analyzed through comparison with various machine learning techniques (i.e., support vector machine (SVM), neural network (NN), decision tree (DT), case-based reasoning (CBR), and logistic regression (LR)). The experimental results and analyses demonstrate that the network indicators generated through SNA can represent soccer team performance and that an accurate win–lose prediction system can be developed using GB technique.

Systematic Model-Based Design and Implementation of Supervisors for Advanced Driver Assistance Systems

The number of advanced driver assistance systems (ADASs) and the level of automation in modern vehicles is increasing at a rapid pace. Moreover, multiple of these ADASs can be active at the same time and therefore may need to interact with each other. As a consequence, the design of the supervisor layer that is responsible for proper coordination of the control tasks performed by the low-level ADASs controllers is becoming more complex and safety-critical. For this reason, there is a strong need for automated synthesis tools that lead to supervisors that are safe by design. In this paper, we present a systematic approach to model-based supervisor design using discrete-event system representations. In particular, this paper shows that the proposed method is suitable to deal with the multiple and complex systems of interacting ADASs. To be more specific, in contrast to current practice, which often relies on textual specifications and exhaustive testing, the proposed method has four main advantages: 1) it is based on mathematically specified requirements that only allow one interpretation; 2) it prevents blocking situations by design; 3) it guarantees correctness in the sense that the resulting supervisor satisfies all the specified requirements; and 4) code is generated from the obtained supervisor which eliminates the need for manual coding. The proposed method is demonstrated by means of a case study on cruise control and adaptive cruise control. The resulting supervisor is validated by simulations and experiments on a modern passenger vehicle. Based on the results presented in this paper, it can be concluded that the model-based supervisor design, simulation, and implementation method is promising and powerful for future applications in the automated vehicle systems.