Control Theory

In this paper, we outline the foundations of a general global optimisation strategy for the solution of multilevel hierarchical and general decentralised multilevel problems, based on our recent developments on multi-parametric programming and control theory. The core idea is to recast each optimisation subproblem, present in the hierarchy, as a multi-parametric programming problem, with parameters being the optimisation variables belonging to the remaining subproblems. This then transforms the multilevel problem into single-level linear/convex optimisation problems. For decentralised systems, where more than one optimisation problem is present at each level of the hierarchy, Nash equilibrium is considered. A three person dynamic optimisation problem is presented to illustrate the mathematical developments.

Functional analysis is a universal methodology, which is able to support NPP and I&C design process. The paper proposes an approach to combining the functional analysis process and I&C design process into a single I&C functional design process. Operation of a system is considered as a set of functions providing not only the achievement of goal, but also keeping material and energy balances. A notation for graphical representation of semantic network (hierarchy of functions) describing a system is suggested. This network includes four levels, namely functional goals, abstract functions level, process functions level, and equipment level. The elements of the hierarchy are connected by three kinds of relationships, namely: parent-child, main-support, and cause-consequence. Then the semantic network (hierarchy) of functions is converted into a functional network which looks as a directed graph. This graph is used for development of control algorithm and for building of instrumentation a...

The relationship between technocratic and socioideological control in organizations is con- tested among scholars. In an attempt to understand this complex interlinkage, the present study examined organizational control processes in inbound and outbound call centers in Bangalore, India. Relying on qualitative interviews and thematic analysis, the study demonstrated how organizations invoke the concept of professionalism in their employees. Organizational efforts in this direction result not only in employee compliance but also internalization of professional- ism such that agents' sense of self changes to embrace employer-defined professionalism. Socioideological control thus sets the stage for the acceptance and effectiveness of techno- cratic control. Rather than viewing organizational identities and organizational cultures as additional or separate extensions of the substantive, structural, material dimensions of control, the findings of the study highlight that socioideolog...

The medical profession has always a high degree of autonomy. However, the rapid growth of health care costs that has started in the second half of the last century, has forced governments to tighten the control over medical practice and introduce managers into medical organizations, and also to induce competitive forces in health care systems. However, there is no conclusive evidence that the juxtaposition of bureaucratic and market control mechanisms with the autonomy of the medical profession has led to cost reduction. These actions strengthened, however, the conflict between the role of a manager focused on cost control and the role of a doctor directed towards quality control. One of the key area where the control mechanisms have low efficacy, is treatment of patients with multi chronic conditions, as in this case, the coordination of the therapeutic process must include the alignment of actions of various specialties. At the organization level bureaucratic mechanisms of coordin...

This paper revisits the use of trend forecasting to determine ordering policy in supply chains by viewing it as a part of the control process for making the supply responsive to demand. Trend forecasting is often used to assess demand—a tracked variable in the control context, which drives supply—a tracking variable. Used in this way, it is often observed to increase instability creating the so-called bullwhip effect. Trend is used on the other hand with reliability to increase stability in controller control, but with the difference that a trend of a ...

A comprehensive study of capacitor placements and real-time control in general unbalanced distribution systems is undertaken. New developments in a loss reduction formula, problem formulations, solution methodology and mathematical justification are presented. The problem is decoupled into two subproblems: the capacitor placement subproblem and the real-time control subproblem. An effective solution algorithm for placing capacitors and determining their real-time control

The design of logic controllers for event-driven systems continue to rely largely on intuitive methods rather than on formal techniques. This approach results in a control code that requires extensive verification, is hard to maintain and modify, and may even fail at times. Supervisory control theory (SCT) provides a formal approach to logic control synthesis. In order to demonstrate the usefulness of the supervisory control theory in manufacturing systems, an educational test-bed that simulates an automated car assembly line has been built using LEGO® blocks. Finite state machines (FSMs) are used for modeling operations of the assembly line, and for the specifications that accomplish the task of successfully completing the assembly repeatedly. Using the technique of SCT, we derive a supervisor that enforces the specifications while offering the maximum flexibility of assembly. Subsequently a controller is extracted from the maximally permissive supervisor for the purpose of implementing the control by selecting, when possible, at most one controllable event from among the ones allowed by the supervisor. Testing to check the correctness of the control code is reduced, since the controller is guaranteed to enforce the specifications.

5th International Conference on Applied Mathematics and Sciences (AMA 2021)will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications impacts and challenges of Mathematics and Sciences. The conference documents practical and theoretical results which make a fundamental contribution for the development of Mathematics and Sciences. The aim of the conference is to provide a platform to the researchers and practitioners from both academia as well as industry to meet and share cutting-edge development in the field. The goal of this Conference is to bring together researchers and practitioners from academia and industry to focus on Mathematics and Sciences advancements, and establishing new collaborations in these areas. Original research papers, state-of-the-art reviews are invited for publication in all areas of Mathematics.

In this project a remote controlled self-balancing mobile robot was designed, built and controlled. This paper gives a summary of the work done in the fields of mechanical design, electronics, software design, system characterization and control theory. This wide array of fields necessary for the realization of the project holds the project up as a leading example in the field of mechatronics. In the paper special focus will be on the modelling of the robotic system and the simulation results of various control methods required for the stabilization of the system.

Given an ideal I in , the polynomial ring in n-indeterminates, the affine variety of I is the set of common zeros in n of all the polynomials that belong to I, and the Hilbert Nullstellensatz states that there is a bijective correspondence between these affine varieties and radical ideals ...

Abstract—This paper provides a theoretical framework for analysis of consensus algorithms for multi-agent networked systems with an emphasis on the role of directed information flow, robustness to changes in network topology due to link/node fail-ures, time-delays, and performance guarantees. An overview of basic concepts of information consensus in networks and methods of convergence and performance analysis for the algorithms are provided. Our analysis framework is based on tools from matrix theory, algebraic graph theory, and control theory. We discuss the connections between consensus problems in networked dynamic systems and diverse applications including synchronization of coupled oscillators, flocking, formation control, fast consensus in small-world networks, Markov processes and gossip-based algorithms, load balancing in networks, rendezvous in space, dis-tributed sensor fusion in sensor networks, and belief propagation. We establish direct connections between spectral and ...

A model based on fuzzy logic is proposed for inventory control. The periodic review model of inventory control with variable order quantity is considered. The model takes into account the dynamics of production–inventory system in a control theoretic approach. The control module combines fuzzy logic with proportional-integral-derivative (PID) control algorithm. It simulates the decision support system to maintain the inventory of the finished product at the desired level in spite of variations in demand. The effectiveness of the proposed control model is illustrated using the actual data of a typical packaging organization operating in the Sultanate of Oman.

This paper explains the implementation of a small-signal model for a new five-level series resonant inverter structure. The proposed circuit combines the advantages of multilevel inverters and the characteristics of the physical phenomena, resonance. The small-signal model offers the possibility to design a linearized linear time-invariant (LTI) model around an equilibrium point based on the first-order Taylor series. After that, the performance of the proposed five-level series resonant inverter and its small-signal model are evaluated in MATLAB/Simulink environment. Compared with a MATLAB model generated using the system identification toolbox, the developed small-signal model exhibited a good accuracy in frequency and time domains. In addition, a hardware test bench is developed to validate the proposed model. Both simulation and experimental results show that the proposed multilevel resonant inverter is very interesting for high-voltage high-frequency applications. As a perspective, from the results obtained, we suggest the use of small-signal AC analysis for multilevel series resonant inverter modeling. The paper contains rich information on the recently used tools for dynamic systems modeling and analysis of nonlinear processes that can be applied to modeling and analyzing other power electronics inverters.

This paper focuses on the temperature control in a multi-zone building. The lumped heat transfer model based on thermal resistance and capacitance is used to analyze the system dynamics and control strategy. The resulting thermal network, including the zones, walls, and ambient environment, may be represented as an undirected graph. The thermal capacitances are the nodes in the graph, connected by thermal resistances as links. We assume the temperature measurements and temperature control elements (heating and cooling) are collocated. We show that the resulting input/output system is strictly passive, and any passive output feedback controller may be used to improve the transient and steady state performance without affecting the closed loop stability. The storage functions associated with passive systems may be used to construct a Lyapunov function, to demonstrate closed loop stability and motivates the construction of an adaptive feedforward control. A four-room example is included to illustrate the performance of the proposed passivity based control strategy.