Temperature control of tank reactors with exothermic reactions is an acknowledgedly difficult task because of complex interacting phenomena, several nonlinearities and unstable dynamics. Traditionally, simple control functions are implemented, implying poor control performance and small operating windows. However, many advanced control schemes have been published, though in many applications th...

In this paper, an almost new control approach called terminal synergetic control which works based on user defined manifold is applied to a nonlinear helicopter model. Stability analysis is convestigated using Lyapunov stability theory. Synergetic controller is applied to this nonlinear fifth-order helicopter model to control height and angle. Simulation results showed that it has faster and sm...

These talks present an overview of a tentative theory of large distance physics. For each large distance L (in dimensionless units), the theory gives two complementary descriptions of spacetime physics: quantum field theory at distances larger than L, string scattering amplitudes at distances smaller than L. The mechanism of the theory is a certain 2d nonlinear model, the λ-model, whose target ...

Quantum field theory (QFT) presents a genuine example of the underdetermination of theory by empirical evidence. There are variants of QFT which are empirically indistinguishable yet support different interpretations. This case is of particular interest to philosophers of physics because, before the philosophical work of interpreting QFT can proceed, the question of which variant should be subj...

Electric AC drives in manufacturing processes are well known and extensively studied. Speed loops can be commonly constructed through a decoupling method like Direct Torque Control (DTC) or Field Oriented Control (FOC) and a PID controller, which lacks of robustness towards torque variations. In this work a robust speed controller is incorporated to a DTC; its robustness is applied to the settl...

This paper presents a robust noniterative algorithm for the design of controllers of a given structure satisfying frequency-dependent sensitivity specifications. The method is well suited for automatic loop shaping, particularly in the context of Quantitative Feedback Theory (QFT), and offers several advantages, including (i) it can be applied to unstructured uncertain plants, be they stable, u...

An important statement in Quantitative Feedback Theory(QFT) is that the nominal plant can be chosen arbitrarily whether or not it is a member of the plant set. Based on this statement, a design method for non-minimum phase and unstable plants proposed by Horowitz is to choose the stable minimum phase plant as the nominal plant. This report shows this statement is incorrect by several counterexa...

Nowadays, hydraulic actuators play an important role in a modern industry where controlled force or position with high accuracy is the most significant demand. This paper presents a new kind of hydraulic load simulator (HLS) for conducting performance and stability test in the bench system where force control is important. The system model consists of a hybrid hydro-electric actuator and anothe...

This paper formulates a robust control for variable time-delay system models. An automatic tuning method for PID-type controller is proposed. The adopted method integrates robust control design using Quantitative Feedback Theory (QFT) with Particle Swan Optimization heuristic algorithms (PSO) to systematize the loop-shaping stage. The objective of the design method is to reach a good compromise...