Corneliu Botan*, Silviu Florin Ostafi*
* Department of Automatic Control, Technical University of Iasi, Iasi, Romania (e-mail: cbotan@ac.tuiasi.ro, fostafi@ac.tuiasi.ro)

Abstract: The paper deals with linear quadratic (LQ) optimal problems with free and fixed-end point. A unified approach for both problems (with fixed and free end-point) allows establishing of analytical formulae for the solution to the same Riccati equation, with different terminal conditions. Certain procedures which start from an initial adequate condition are established for the problem with free end-point. The necessity of the inverse time computing of the solution to Riccati equation is thus avoided.
Keywords: optimal control, Riccati equations, differential equations, analytical solution, final values.

Bogdan Burlacu*, Lavinia Ferariu*
*Department of Automatic Control and Industrial Informatics, "Gheorghe Asachi" Technical University of Iasi, Romania, Bd. D. Mangeron 27, Iasi Ro-700050 (e-mail: bburlacu@ ac.tuiasi.ro, lferaru@ac.tuiasi.ro).

Abstract: This paper presents a new neuro-evolutionary system for the design of feed forward hybrid neural models. Every individual is directly encoded as a directed acyclic graph, allowing the development of partially interconnected architectures with heterogeneous layers including both local and global neurons. The use of different neuron types provides improved performances in terms of approximation quality for a large class of nonlinear system identification problems, while the direct graph encoding ensures a simpler interpretation of the hierarchical individuals, as well as a compact representation. The authors recommend a special minimally sufficient set of functions and customized compatible genetic operators, which exploit the inherent characteristics of the neural architectures (modularity, high interconnectivity and high level of parallelism). An extra effort is made towards improving the genetic algorithms convergence speed by introducing a special sensitivity score for each hidden neuron as part of a novel crossover strategy aimed to preserve valuable structural blocks inside the individual. Featuring multithreaded execution and specialized data structures, the C application scales well on multi core computers and has a low memory footprint, being suitable for complex nonlinear identification problems.
Keywords: genetic programming, genetic operators, neural networks, system identification, optimization.

Camelia Maican*, Matei Vînatoru*, Gabriela Canureci**
*Automation Department, University of Craiova, Craiova, Romania, (e-mail: camelia@automation.ucv.ro, vinatoru@automation.ucv.ro)
**IPA CIFAT Craiova, Romania, (e-mail: gabriela.canureci@ipacv.ro)

Abstract: The scope of this paper is to define the transfer function of the super-heater for the implementation of some supplementary control reactions in fault conditions of the super-heater actuator. This control structure maintains the stability of control systems and assures a faster response to a variation of the steam flow of the entrance of the turbine.
Keywords: steam temperature, fault detection, residuals, super-heater and control.

Dan Marghitu*, Seunghun Lee*, Dorian Cojocaru*
* Mechanical Engineering Department, Auburn University, AL 36849 USA, (e-mail: marghitu@auburn.edu)
** Mechatronics Engineering Department, University of Craiova, Romania

Abstract: The impact of a free planar link with a granular material is studied in this research. The force of the granular material on the link is a linear superposition of a depth dependent resistance force and a velocity dependent frictional force. The granular material is defined as a conglomeration of discrete solids and both the solid like and fluid liquid characteristics are considered. The impact is examined from the contact moment until rest using various initial conditions. The results of the simulations are analyzed taking into consideration the initial impact conditions. The system under higher initial velocity comes to rest faster than the same system under lower initial velocity.
Keywords: impact, granular material, stopping time, initial velocity.

Marius Marian*
*University of Craiova, Department of Computer Science, 200585-Craiova, Romania (Tel: +40-251-438198; e-mail: marius.marian@cs.ucv.ro)

Abstract: This paper analyzes the issues faced during the deployment of an academic IT security infrastructure. The challenges during the planning and building of the public-key infrastructure of the Faculty of Automation, Computing and Electronics are detailed along with some of the practical solutions identified.
Keywords: public-key infrastructure, digital certificates.

Dan Adrian Marior*, Constantin Cîrciumaru**
*Department of Automation in the Faculty of Automation, Computers and Electronics, Craiova ( e-mail: marior@ automation.ucv.ro)
** IT Department of the Ford Motor Company, Craiova(e-mail: ccircium@ford.com)

Abstract: The paper deals with the problem of managing the utility vehicle park of the Ford Motor Company plant in Craiova. In order to obtain the minimal cost solution, we propose a sensorless parking management system, which handles the parking spots, the tracking of the vehicles (whether they are inside the parking area or not), and reports to management in case there are situations that go beyond normal workflow rules.
Keywords: Sensorless, Management, Ford, parking, ASP.NET.

Maria Muntean*, Honoriu Valean**
*1 Decembrie 1918 University of Alba Iulia, Romania, (e-mail: mmuntean@ uab.ro)
**Technical University of Cluj Napoca, Romania, (e-mail: Honoriu.Valean@aut.utcluj.ro)

Abstract: A problem arises in data mining, when classifying unbalanced datasets using Support Vector Machines. Because of the uneven distribution and the soft margin of the classifier, the algorithm tries to improve the general accuracy of classifying a dataset, and in this process it might misclassify a lot of weakly represented classes, confusing their class instances as overshoot values that appear in the dataset, and thus ignoring them. This paper introduces the Enhancer, a new algorithm that improves the Cost-sensitive classification for Support Vector Machines, by multiplying in the training step the instances of the underrepresented classes. We have discovered that by oversampling the instances of the class of interest, we are helping the Support Vector Machine algorithm to overcome the soft margin. As an effect, it classifies better future instances of this class of interest. The experiments were performed using real data acquired from a monitoring sensor system, stored in three databases and replicated on an aggregation server.
Keywords: Learning Algorithms, Classification, Accuracy, Improvement, Wireless Sensor Network.

Manoiu-Olaru Sorin*, Nitulescu Mircea**
*Department of Automation, Electronics and Mechatronics, University of Craiova, Romania (e-mail:manoiusorin2006@yahoo.com)
** Department of Automation, Electronics and Mechatronics, University of Craiova, Romania (e-mail:nitulescu@robotics.ucv.ro)

Abstract: In this paper the authors present a software program to simulate hexapod robot stability in gravitational field for a certain configuration of legs and some basic walking simulations using Matlab software package. First the complete kinematical model of the leg is calculated and the direct dynamical model is presented. The kinematical model of the leg was obtained using Denavit - Hartenberg algorithm. A workspace analysis of the leg is made in order to analyze collision during walking and impose the necessary constrains. Then a hexapod robot structure using this kind of leg is presented and simulated using Matlab software package. A virtual simulation platform was created for the robot in order to simulate robot static stability and basic movement algorithm. The analysis of the robot static stability is made for different cases of locomotion on horizontal surface and for different leg configuration. Also the simulation platform allows connection of a physical leg to the computer through Arduino Duemilanove development board in order to simulate different movement algorithms and test the functionality of the structure. This part is an experimental one and will be improve in the future. Moving the leg tip from one point to another is made in two phases: stance phase and swing phase. The paper includes some experimental results related to the static gravitational stability depending on the support polygon, single leg control and some basic walking simulations.
Keywords: Matlab, gravitational stability, Denavit-Hartenberg representation, model, hexapod.

Theodor Oprica, Matei Vînatoru*
*Department of Automatic Control, University of Craiova, Romania (e-mail: oprica_theodor@yahoo.com, vinatoru@automation.ucv.ro)

Abstract: The impossibility of road infrastructure development in accordance with the accelerated rhythm of transport necessity increasing results in sharpening of road congestion phenomenon, with adverse effects in all areas of life. An efficient street traffic control through junctions can significantly ameliorate this phenomenon's negative effects maintaining traffic fluidity. In this paper we present the two street traffic control strategies currently available and how to implement them at an intersection. Finally, a comparative case study on an intersection in the city of Craiova for three different signal plans: the fixed signal plan utilized in present, an alternative fixed plan and the adapted plan based on signals actualization in real time, also evaluating their efficiency relying on quality indicators.
Keywords: signal plan, default control, actuated control, delay time, sensor network.

Vladimir Rasvan*
*Department of Automatic Control, University of Craiova, Craiova, Romania (e-mail: {vrasvan, dpopescu, daniela}@automation.ucv.ro)

Abstract: It has been established by now that the problem of the absolute stability originates from a paper of B.V. Bulgakov published in 1942. The engineering application generating the problem was the so called gyroscopic pendulum, with various applications in stabilization of ships, aircrafts or armored cars. Even if nowadays the technical implementation of this device might be completely different, the dynamics is essentially unchanged. For this reason, it became in the next decades a genuine benchmark in the absolute stability. In this paper there are considered stability and oscillations of the gyroscopic pendulum based on both achievements of the absolute stability - the Liapunov function and the frequency domain inequalities.
Keywords: Absolute stability, Frequency domain inequalities, Liapunov function.

Roxana Stanica*, Emil Petre**
*University of Craiova, Romania (e-mail: roxana_batm@yahoo.com)
**University of Craiova, Romania (e-mail: epetre@automation.ucv.ro)

Abstract: Ethernet in the First Mile (EFM) specifies the protocols and Ethernet interfaces for using Ethernet over access links as a first-mile technology and transforming it into a highly reliable technology. EFM standard defines the Operation, Administration, and Maintenance (OAM) feature as an optional sub-layer just above the Ethernet Media Access Controller (MAC). This paper presents a new EFM protocol structure (for monitoring and troubleshooting the network) that is based on OAM feature. The OAM structure permits the configuration of different parameters such as timers, link connectivity, packet's priority, latency, frame-loss, and jitter. By using OAM, service providers can measure and ensure Service Level Agreements (SLA). Keywords: Ethernet first mile, OAM, timer, ping, loopback, display

Razvan Tanasie*
* Software Engineering Department, University of Craiova, A.I.Cuza, 13,Craiova, RO-200585, Romania (e-mail: rtanasie@software.ucv.ro)

Abstract: An enhanced graphics engine was developed using Microsoft C++ and DirectX libraries. This engine is part of a multi-purpose platform used, in this case, to simulate an algorithm for fuzzy dynamic path finding using potential fields. The fuzzy system uses singleton fuzzifier, product inference engine and center average defuzzifier. The developed algorithm is for a dynamic environment with multiple moving obstacles. The inputs are a squared space map, the initial and target position of the wanderer, the initial position and motion parameters of the obstacles. The algorithm computes, if possible, a path from the initial position of the wanderer to its target, using the weighted artificial potential field approach.
Keywords: path finding, graphics engine, potential fields, fuzzy systems, dynamic systems, simulation.