We show that a self-tuning mechanism of the cosmological constant could work in 5D non-compact space-time with a Z 2 symmetry in the presence of a massless scalar field. The standard model matter fields live only on the 4D brane. The change of vacuum energy on the brane (brane cosmological constant) by, for instance, electroweak and QCD phase transitions, just gives rise to dynamical shifts of ...

In this paper we propose a method for optimization of closed-loop parameters and continuous-time sampling period by digital self-tuning PID control of pressure plant. The quality of pressure plant control is experimentally compared between two modifications of digital self-tuning PID controllers. The results of adaptive pressure plant control show that the optimization of closed-loop parameters...

This paper presents a comparative study between an adaptive fuzzy controller and an adaptive selftuning controller with application to excitation control of a synchronous generator. The adaptive self-tuning controller is based on a dual action, obviously on control input, and also on reference signal. The proposed adaptive fuzzy controller includes a mechanism to adapt one of the tuning paramet...

Reducing the exhaust emissions of an spark ignition engine by means of engine modifications requires consideration of the effects of these modifications on the variations of crankshaft torque and the engine roughness respectively. Only if the roughness does not exceed a certain level the vehicle do not begin to surge. This paper presents a method for controlling the air-fuel ratio for a lean bu...

Activated sludge wastewater treatment processes are difficult to be controlled because of their complex and nonlinear behavior, however, he control of the dissolved oxygen level in the reactors plays an important role in the operation of the facility. For this reason a new pproach is studied in this paper using simulated case-study approach: model predictive control (MPC) has been applied to co...

Suspension system plays an imperative role in retaining the continuous road wheel contact for better road holding. In this paper, fuzzy self-tuning of PID controller is designed to control of active suspension system for quarter car model. A fuzzy self-tuning is used to develop the optimal control gain for PID controller (proportional, integral, and derivative gains) to minimize suspension work...

This paper presents a constrained Model Predictive Control (MPC) strategy enriched with soft-control techniques as neural networks and fuzzy logic, to incorporate self-tuning capabilities and reliability aspects for the management of drinking water networks (DWNs). The control system architecture consists in a multilayer controller with three hierarchical layers: learning and planning layer, su...

In this document we present an overview of Transactional Memory models, as well as a comparison to traditional parallel frameworks. In this context, we follow with an analysis on the problem of self-tuning concurrency control in transactional memory, where different mechanisms are used to predict and adjust an application’s concurrency level with respect to available parallelism. We are particu...

Two controllers which extend the PD+I fuzzy logic controller to deal with the plant having time varying nonlinear dynamics are proposed. The adaptation ability of the first self tuning PD+I fuzzy logic controller (STPD+I_31) is achieved by adjusting the output scaling factor automatically thereby contributing to significant improvement in performance. Second controller (STPD+I_9) is the simplif...

The 3 degree of freedom (3-DOF) helicopter system is a typical higher-order times, instability, multi-variable, nonlinear and strong coupling control system. This paper presents the analysis of the mathematical model and the basic principle of PID control and fuzzy PID control, which are based on 3-DOF helicopter systems. In allusion to balance control of 3-DOF helicopter system, PID controller...