Doina Zmaranda

Interpolative control algorithm applied on a 3D-mechatronic system

The study presented in the paper aims to investigate the control performances of an interpolative control algorithm applied on a complex nonlinear system. In the specified context, the study was made based on results obtained through simulations on a 3D-Crane. The results were compared with data obtained from a classical PID system that also incorporates the 3D-Crane.

Redundancy method used in PLC related applications

PLC related applications are more complex as far as more components are involved. If some error occurs, diagnosis can take some time, but a logical procedure will shorten the time needed to locate the fault. The probability of failure of different parts of typical PLC systems shows [1] that 95% of PLC systems are external faults and occur on plant items such as: sensors, actuators, transducers, limit switchers, and others. The possibility of determining the validity of the data gathered from all transducers of the control system assures a way of short time fault detection. Consequently, a fault-tolerant control system must be implemented using redundant structures, representing an alternative for malfunctioning element detection. This paper presents a method used to design and implement a control system based on redundant structures. A case study for the geothermal power plant at the University of Oradea was developed. The redundant structure considered was simulated using MathLab/Simulink and analyzed using different scenarios. Finally, a possible implementation of resulting control system structure is done using a programmable logical controller (PLC).

MATLAB-SIMULINK modeling for the Well Station of a Geothermal power Plant

In this paper, a MATLAB-SIMULINK-based model for the Well Station from the Geothermal Plant at the University of Oradea is developed. The Well Station component is in charge for producing (extracting) geothermal water that should be used for heating purposes in the university campus.

A Comparative Study between Applications Developed for Android and iOS

Now-a-days, mobile applications implement complex functionalities that use device’s core features extensively. This paper realizes a performance analysis of the most important core features used frequently in mobile application development: asynchronous multi-threaded code execution, drawing views/elements on the screen and basic network communications. While multiple mobile platforms have emerged in recent years, in this paper two well-established and popular operating systems were considered for comparison and testing: Android and iOS. Thus, two basic applications featuring the same functionality and complexity were developed to run natively on both platforms. Applications were developed by using development languages and tools recommended for each operating system. This paper aims to highlight the differences between the two operating systems by analyzing core feature performance metrics for both functionally identical mobile applications developed for each platform. Results obtained could be further used for guiding the optimization of application’s development process for each considered operating system.

Numerical algorithms for Lyapunov stability analysis of interpolative control structures

The complexity and specificity of stability analysis applied to interpolative-type control structures makes the study of such property a difficult, almost impossible task - at least in the analytical manner. Therefore, a better solution could be represented by the numerical approach. In this context, this paper starts with developing some methods and techniques with applicability for analysis of the interpolative-type controllers, based on Lyapunov method perspective. These methodological aspects are gathered together into a specific procedural algorithm. Based on this algorithm, a set of MATLAB-SIMULINK programs able to offer, in a flexible and user-interactive way, a possible solution to Lyapunov-stability analysis for a class of interpolative-type control systems with linear or non-linear processes of 2nd and 3rd order are developed. The solution based on the implemented software packages was finally validated through some practical examples.

A Tool for Modeling and Simulation of Real-Time Systems Behaviour

In several real-time applications, tasks are not only subjected to complete their deadlines, but more control of the scheduling process is required. In such situations, quality of service is interpreted in many ways (jitters, response times, etc.). In other real-time environments the objective is to optimize a performance measure while respecting release times and deadlines; other environments permit modifications of release times, but not of the deadline times, in a controlled manner. This paper focus on additional issues related on precedence constrains and variable execution times that could be considered during scheduling. In this idea, the paper presents a way of possible integration of such issues into a tool used for modelling and simulation of real-time systems behaviour.