Annals 2011

Abstract: Allmost airborne ultrasonic images used in robotics have artefacts and distorstions, when comparing real objects with those presented in ultrasonic images. The differences between reral and reference images have various causes, as assymetries in directivity of ultrasonic transducers, reflections on the explored environment, non-linearities of the processing blocks. Previous works on the problem, showed that such distortions could be removed or attenutated by classical or adaptive filtering of ultrrasonic images. This paper presents the results artefacts removing made by image fusion approach and wavelet transform. Results are accurate and at the same level of quality, comparing with other explored methods, i.e. based on filtering.

G.Petrea, A. Filipescu, E.Minca, A. Voda, A. Filipescu Jr., A. Serbencu: Hybrid Modelling Based Control of an Processing/Reprocessing Mechatronics Line Served by an Autonomous Robotic System

Abstract: The new idea in this paper is to make a processing line capable of reprocessing pieces that have not passed the quality test. The focus is to provide a model of the processing line and to introduce in the process a wheeled mobile robot (WMR) equipped with a robotic manipulator (RM) in order to transport pieces, for reprocessing. For this purpose, an processing/reprocessing mechatronics line (P/RML) and a timed hybrid Petri nets (THPN) model will be used in modeling and control of the mechatronics line, with a fixed number of workstations, served by a WMR equipped with (RM). The THPN model is a hybrid type, where P/RML is the discrete part and WMR with RM is the continuous part. The reprocessing starts after the piece fails the quality test. The WMR with RM is used only at the start of reprocessing, in order to transport the pieces from the warehouse to the beginning of the processing line.

M. I. Andreica: Counting Minimum Cost Bounded Degree Subtrees in Graphs with Small 2-Vertex-Connected Components Platform

Abstract: In this paper we present new algorithms for counting minimum cost bounded degree subtrees in connected graphs in which the 2-vertex-connected (biconnected) components have small sizes. The 2-vertex-connected components and the cut vertices can be organized into a block-cut vertex tree which is also a tree decomposition with small width of the graph. We present a dynamic programming algorithm which is very efficient on this particular tree decomposition and we also discuss methods of solving the problem given an arbitrary tree decomposition with small width. Among some of the most important results is an algorithm which can efficiently compute the number of subtrees of a (small) graph corresponding to each possible degree sequence.

Keywords: tree decomposition, block-cut vertex tree, 2-vertex-connected components, bounded-degree subtree.

A. Chauhan, L. Kumar: Conceptual Framework for Cloud Based Ubiquitous Learning Environment through M – Learning

Abstract: Cloud computing is a recent trend in storing and managing data over a network. Cloud computing entrusts remote services with a user's data, software and computation. Here, we propose a design where a ubiquitous learning could be possible through m - learning, where people (in our case students) can access data like lecture notes, assignments etc. on their mobile devices, from anywhere. A university can have a dedicated cloud which everyone could access and upload their content, which would be accessible from anywhere and easily run on mobile devices, be it any platform or operating system, making it convenient for everyone to access and read data without the use of heavy & expensive software. Student can access their college data from a dedicated web application or a mobile application synchronized with the university cloud. The next generation computing started with the advent of Cloud computing and this framework would integrate the energy efficient cloud based service with m – learning, making the education system cheap and paper free. The display limitation of these devices means that it is crucial to deliver the right content at the right time.

Keywords: Cloud Computing, Mobile Application, Mobile Learning, Private Cloud.

Abstract: This article represents a new method to select several distinct routes among cluster heads want to limit the direct connection of all cluster heads and base station. Cluster heads use those near base station to transfer their own data. Thus, the method selects several distinct, pretty, equal, long routes forms workload balance among cluster heads, decrease energy consumption. Finally, it increases the network lifetime. This method investigates a hierarchy convergence sensor network includes cluster heads, so that each of them are responsible to collect and send data from members.

Keywords: Clustering, Data Collection, Wireless Sensor Network (WSN), Network lifetime, energy

R. Solea, M. Gaiceanu, B. Codres, C. Eni: Performancen Comparison of Sliding Mode Controller and Conventional PID Controller for DC Motor

Abstract: This paper is concerned with the performance comparison of Sliding Mode Controller and conventional PID Controller for the control of DC Motor. The DC motor can be modeled as a linear time invariant single input single output (SISO) system. Direct Current (DC) motors have been used extensively in industry mainly because of the simple strategies required to achieve good performance in speed or position control applications. Conventional controllers (such as PID-algorithm) are lack of robustness, therefore disturbances affect the system synchronization and quality of the production. Performance of these controllers has been verified through simulation results using MATLAB/SIMULINK software. The performance of sliding mode controller is superior to conventional PID controllers even in the presence of disturbances.

Keywords: Direct Current Motor, Sliding-mode Control, Milling Process

M. B. Ilie: A survey on Image Processing Techniques in the Context of Content Based Image Retrieval

Abstract: This paper presents an overview of the current image processing techniques used to solve various problems, especially in the field of image indexing/retrieval. We aim to provide a solid, comprehensive reference source for other researchers involved in the image processing field. We will be describe the search spaces, the most common techniques, their advantages and drawbacks and the alternatives proposed by various researchers in the community

Keywords: CBIR, image processing, image descriptors.

G. Sundar, S. Ramareddy: Static Analysis of STATCOM for Enhancement of Voltage on Transmission Line

Abstract: The recent development of Power- Electronics controller introduces the use of various FACTS devices in power systems networks. FACTS devices can control the power system network condition in expediting manner and this feature of FACTS devices can be demoralizing to improve the steady state stability of a system. This paper aims to investigate the static analysis based on a 6-pulse voltage-source converter for Static Synchronous Compensator (STATCOM). A 3-bus system has been used for the proposed STATCOM model. The STATCOM model and its simulation are performed using MATLAB’s Simulink and Power System Blockset. Static analysis is done for STATCOM to verify its capability in improving voltage regulation in the transmission systems.

Keywords: STATCOM, Steady state analysis, Multilevel Converter, Transmission line.

B. Codres, M. Gaiceanu, R. Solea, C. Eni: Model Predictive Speed Control for Three Phase Induction Motor

Abstract: In this paper an alternative method to the classical control of the induction motor drive system is proposed. More exactly, a model predictive control (MPC) for the rotor speed of the induction motor is presented. The numerical simulation is done using Simulink and then the results are compared with a classical approach (PI controller).

Keywords: model predictive control, three phase induction motor, Matlab / Simulink.

G. Vasiliu: IT&C Solutions for Intelligent Transportation Systems

Abstract: Road traffic congestion has incredibly high social costs, due to unnecessary fuel consumption, environment pollution, wasted time, and increased risk of accidents. As the road infrastructure obviously grows slower than the number of vehicles, the situation constantly deteriorated in the past decades, thus requiring immediate attention from both researchers and decision makers. This paper presents a couple of IT&C based solutions for Intelligent Transportation Systems, which make the object of two patent applications submitted to the Romanian Patent Office OSIM. The first solution is an improved GPS navigation assistant for road vehicles, capable to produce real-time estimations of the traffic fluency. The other describes the principles of implementation of “virtual road signs” based on Vehicular Ad-hoc Networks (VANETs).

Keywords: GPS Navigation, Intelligent Transportation Systems, Traffic Congestion, Virtual Road Signs, VANETs

2013: Volume 36, Number 1

Table of Contents

2013: Volume 36, Number 2

Table of Contents