Melita Ahic-Djokic

Simple Computer Vision System for Chess Playing Robot Manipulator as a Project-based Learning Example

This paper presents an example of project-based learning (PBL) in an undergraduate course on Image processing. The design of a simple, low-cost computer vision system for implementation on a chess-playing capable robot is discussed. The system is based on a standard CCD camera and a personal computer. This project is a good tool for learning most of the course material that would otherwise be mastered by homework problems and study before an exam. An algorithm which detects chess moves is proposed. It compares two or more frames captured before, during and after a played chess move, and finds differences between them, which are used to define a played chess move. Further image processing is required to eliminate false readings, recognize direction of chess moves, end eliminate image distortion. Many Image processing problems and solutions can be introduced to students, through the proposed algorithm. The results are encouraging - students without any previous knowledge in image processing and advanced topics, such as artificial intelligence (neural networks etc.), may attain a chess move recognition success rate greater than 95%, in controlled light environments.

Analysis of off-line handwritten text samples of different gender using shape descriptors

The human experience in the analysis of the handwriting of male and female writers indicates that gender affects the appearance of the handwritten text. These differences are usually very difficult to describe numerically. In order to analyze the handwriting differences between male and female writers, several shape description techniques, such as the tangent angle function, curvature function and Fourier descriptors, were used in this paper. As an additional contribution of the paper, a database of 3766 off-line handwritten cursive and capitalized written words has been created. The database consists of male and female handwriting samples, classified by gender and handedness. The experimental results show that typical attributes of male and female handwritings imply certain differences in shape decriptors, and those differences have the potential for usage in gender handwriting discrimination.

Weighted-function based algorithm for retrieving handwriting trajectory from off-line data

Individuality of handwriting is the reason why it is used as a common base element for detecting character traits of the writer. It is believed that dynamic information improve the accuracy of the analysis, but they are not contained in an offline handwritten text. In order to recover dynamic information, a novel approach for handwriting trajectory recovery is proposed in this paper. The procedure is based on computing the objective function, which depends on parameters such as the angle of movement, path length, air pen tip movements, etc. The analysis is performed in MATLAB program package, using the text samples from IAM-OnDB database. The experimental results indicate that the average effectiveness of the proposed algorithm is above 75%.

A Hybrid Visualization of the Environment using Smart Ultrasound-based Sensor Arrays

This paper presents the work in progress on the design and testing of a distributed ultrasound-based sensory system for hybrid 1D and 2D environment visualisation. Many common sensors used in robotics, such as infrared and ultrasonic sensors, cameras and lasers mainly focus on quantifying distances and shapes, while rarely have the ability to differentiate among different sensed surfaces/materials. We propose an inexpensive prototype sensory system based on popular ultrasonic sensors which uses ultrasonic reflections to determine the acoustic reflection coefficients. This additional feature allows differentiating among sensed objects. Moreover, the developed ultrasonic cells are equipped with a microcontroller for basic signal processing and a communication link for integration into a sensor network. In this paper, we discuss the possibility of fusing obtained sensor array data and laser measurements.

Design of ultrasound-based sensory system for environment inspection robots

Many robotic systems rely on infrared sensors, lasers, cameras and/or ultrasonic transducers for perceiving their environment. Most of these sensors can easily determine the distances to the surrounding objects, and even their shape. However, they are often unable to discriminate among different nearby-placed objects, obstacles, materials or surfaces. This paper presents the design and development of a low-cost ultrasonic-based sensory system, which is able to exploit the information contained in the magnitudes of the reflected sound waves. Therefore, the common ultrasonic distance measurement is complemented with the value of the acoustic reflection coefficient of the observed object. The estimated reflection coefficient facilitates the classification of different materials. Experiments are conducted to demonstrate solid performance of the proposed sensory system.

Design of a distributed ultrasound-based sensory system

Different sensors may be used for a robot environment analysis: infrared sensors, laser sensors, sonars, RGB and depth cameras. Most of them provide satisfying information about the distance and the shape of observed objects. However, the main drawback of these sensors is the inability to discriminate among different analyzed objects if the latter share the same color, texture or distance. A distributed ultrasound-based sensory system composed from multiple ultrasonic cells is proposed. The system uses a master-slave control architecture. This paper presents the most important part of such system - a low-cost ultrasonic cell with the ability to classify objects by exploiting the magnitude of reflected ultrasonic waves. Traditional ultrasonic sensors only provide information about the distance, but the presented ultrasonic cell also measures the acoustic reflection coefficient of analyzed object. This coefficient allows to differ among materials or objects. Experiments are conducted to demonstrate the performance of the proposed ultrasonic cell.

PROCESS OF EDUCATION AND TRAINING IN DEVELOPING COUNTRIES AS AN ADAPTIVE SYSTEM OF CONTROL

Abstract Process of education and training in the countries all over the world is regulatedby law and founded on legal norms and standards. Process of education and training is prograrmned to provide knowledge for future, should be rational, cannot be considered as independent and has to be based on the worlds standards of quantity and quality of knowledge given. Developing cOlmtries especially have to maintain and pursue clearly defined goals to be achieved, as well as guiding principles behind the system of education andtraining. It is convenient to observe the process of education and training, in developing countries, as an adaptive system of management with a reference model, where the reference model could be selected among some of the worlds leading centres (universities, research centres etc) for the process of education and training, in the same field and profession. In developing countries, the process of education and training has to be an adaptable system, upon which an influence can be exercised, through the mechanism of adaptation. It is important that the evaluation of the process of education and training in developing countries is done in objective and unbiased manner, and necessary changes in the process of education and training suggested.