Cătălin Alexandru

Learn More
In this paper is presented a novel dialogistic, socio-cultural perspective and an associated software tool, which provide structured visualisation and analysis means of Computer Supported Collaborative Learning chat conversations. The implemented tools use knowledge-based techniques and are based on Bakhtin's dialogistic paradigm. They visualize the(More)
The paper presents the virtual prototype of an automotive suspension system with force generator actuator. The active suspensions use sensors to measure the accelerations of sprung mass and unsprung mass, the analog signals from the sensors being transmitted to the controller, which communicates with the force actuator. In this way, the passenger comfort(More)
In this paper, we propose a strategy for optimizing the tracking systems, which is based on the design of the optimal motion law for obtaining as much as possible incident radiation with minimum consumption for driving the system. The optimization is made by reducing the angular field of the panel without significantly affecting the incoming solar energy.(More)
The purpose of the paper is to develop the optimization procedure for a photovoltaic tracking mechanism. The design objective is to minimize the motor forces for moving the panel, decreasing in this way the power consumption for orientation. The optimization strategy is possible by developing the dynamic model of the tracking mechanism, which is a multibody(More)
In paper, the virtual prototype of the rolling – guiding – suspension system of an off-road vehicle is presented. The prototype has been made with the MBS software ADAMS, and takes into consideration the geometric restrictions as well as the nonlinear characteristics of the elastic and damping elements. The experiment designed is one frequently carried by(More)
We present a single generalized method for computing skeletons for arbitrary objects in both 2D and 3D space. We also present a method for computing the multiscale boundary-collapse importance metric for arbitrary 2D shapes in an in-cremental fashion, the results of which are comparable to the AFMM Star for 2D shapes. Finally, we reveal an approach which(More)
This paper approaches a dual-axis equatorial tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. The innovative aspect in the solar tracker design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are(More)
Increasingly " social computation " will be used in the delivery of key services, particularly public services. Social computation is a combination of computational infrastructure, voluntary and paid human effort together with an incentive structure to encourage and reinforce participation. For example, in care we will see the use of family and friends to(More)
The purpose of this paper is to model and simulate a 6 DOF robotic system with revolute joints in order to optimize the motion law which results in uniform coating deposited by spray pyrolysis. The structure and the complexity of the robotized system are determined by the necessary movements in the spray pyrolysis process. The nozzle (end-effector of the(More)