2015: Volume 38, Number 1                                                     

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2015: Volume 38, Number 1

Table of Contents

 

 B. Codreș, M. Găiceanu, Ș. Ciută: Speed Control for Three Phase Induction Motor using Adaline Neural Networks (pp. 5-10)
Abstract  Full Text

V. Mînzu, I. Aramă: Nonlinear discrete Model for the Control of a Sewer Network (pp. 11-16)
Abstract  Full Text

M. H. Allaymoun, Ș. Trausan-Matu: Rhetorical Structure Analysis for Assessing Collaborative Processes in CSCL (pp. 17-22)
Abstract  Full Text

N. Mărășescu: Equipments State Evaluation using Fuzzy Methods (pp. 23-26)
Abstract  Full Text

V. Mînzu, I. Aramă: Sewer Network Discharge Optimization using the Dynamic Programming (pp. 27-33)
Abstract  Full Text

 

 

 

B. Codreș, M. Găiceanu, Ș. Ciută: Speed Control for Three Phase Induction Motor using Adaline Neural Networks

Abstract: The speed control of the three phase induction motor is still a challenging problem. Although the results obtained by means of the conventional control are very good, many researches in this area are ongoing. The authors propose a different control approach based on artificial intelligence. The control signals for speed, torque and flux regulation are computed using three ADALINE (Adaptive Linear Neuron) neural networks. The numerical simulations are made in Simulink and the obtained results are compared with the conventional drive approach (cascaded PI controller).

Keywords: ADALINE neural network, three phase induction motor, Matlab / Simulink.

 

 

V. Mînzu, I. Aramă: Nonlinear discrete Model for the Control of a Sewer Network

Abstract: This paper proposes a nonlinear discrete model for a sewer network aiming to minimize the total overflow volume generated by the influent collected in its area, in the horizon of the control problem. The sewer network is modeled as a nonlinear discrete dynamic system. The control objective leads to an optimization problem with constraints on control and state variables.

 

Keywords: nonlinear discrete dynamic systems, optimal control, sewer network.

 

M. H. Allaymoun, Ș. Trausan-Matu: Rhetorical Structure Analysis for Assessing Collaborative Processes in CSCL

Abstract: This paper presents a research on using rhetorical structures for assessing collaborative processes in Computer-Supported Collaborative Learning (CSCL) chats. For this purpose, the ideas of Bakhtin’s dialogism theory and Trausan-Matu’s polyphonic model are used, starting from the identification of the threads of repeated words from chats. Cue phrases and their usage in linking the identified threads are also considered. The results are presented in statistical tables and graphics that ease the understanding of the collaborative process, helping teachers to analyze and assess students' collaborative chats. It also allows students to know and understand the interactions and how it contributes to the conversation.

Keywords: Computer Supported Collaborative Learning; Collaboration Assessment; Chat Conversations; Rhetorical structures; Cue phrases.

 

 

N. Mărășescu: Equipments State Evaluation using Fuzzy Methods

Abstract: The paper presents an optimal renewal strategy for the diagnosis of the equipments real state using fuzzy methods. For the calculation of the probability estimations, the facilities provided by fuzzy medium within the MATLAB have been used.

Abstract: It is necessary to adopt an optimal control that allows an efficient usage of the existing sewer networks, in order to avoid the building of new retention facilities. The main objective of the control action is to minimize the overflow volume of a sewer network. This paper proposes a method to apply a solution obtained by discrete dynamic programming through a realistic closed loop system.