The problem of motion planning and control of mobile robots has attracted the interest of researchers in view of its theoretical challenges because of their obvious relevance in applications. From a control viewpoint, the peculiar nature of nonholonomic kinematics and dynamic complexity of the mobile robot makes that feedback stabilization at a given posture cannot be achieved via smooth time-invariant control (Oriolo et al., 2002). This indicates that the problem is truly nonlinear; linear control is ineffective, and innovative design techniques are needed. In recent years, a lot of interest has been devoted to the stabilization and tracking of mobile robots. In the field of mobile robotics, it is an accepted practice to work with dynamical models to obtain stable motion control laws for trajectory following or goal reaching (Fierro & Lewis, 1997). In the case of control of a dynamic model of mobile robots authors usually used linear and angular velocities of the robot (Fierro & Lewis, 1997; Fukao et al., 2000) or torques (Rajagopalan & Barakat , 1997; Topalov et al., 1998) as an input control vector. The central problem in this paper is reduction of control torques during the reference position tracking. In the case of dynamic mobile robot model, the position control law ought to be nonlinear in order to ensure the stability of the error that is its convergence to zero (Oriollo et al., 2002). The most authors solved the problem of mobile robot stability using nonlinear backstepping algorithm (Tanner & Kyriakopoulos, 2003) with constant parameters (Fierro & Lewis, 1997), or with the known functions (Oriollo et al., 2002). In (Tanner & Kyriakopoulos, 2003) a combined kinematic/torque controller law is developed using backstepping algorithm and stability is guaranteed by Lyapunov theory. In (Oriollo et al., 2002) method for solving trajectory tracking as well as posture stabilization problems, based on the unifying framework of dynamic feedback linearization was presented. The objective of this chapter is to present advanced nonlinear control methods for solving trajectory tracking as well as convergence of stability conditions. For these purposes we developed a backstepping (Velagic et al., 2006) and fuzzy logic position controllers (Lacevic, et al., 2007). It is important to note that optimal parameters of both controllers are adjusted using genetic algorithms. The novelty of this evolutionary approach lies in automatic obtaining of suboptimal set of control parameters which differs from standard manual adjustment presented in (Hu & Yang, 2001; Oriolo et al., 2002). The considered motion control system of the mobile robot has two levels. The lower level subsystem deals with the

The paper presents design and implementation of a portable modular wavemaker system for producing regular and irregular waves in laboratory basins and fl umes. The system was built for the purpose of testing the impact of the sea waves on ships and coastal facilities. It is suitable for generation of all tipes regular and irregular surface waves. Modular system structure maintains high degree of fl exibility and reusability. Finally, the testing process on the physical model of Split harbour is described, and the currently obtained results are shown.

The aim of the study was to evaluate the long-term effects of antidepressive therapy on chronic pain and related disability, and masseter silent period in psychiatric depressive patients with temporomandibular disorders (TMD). The study included hospitalized psychiatric depressive patients on antidepressive therapy protocol (tetracyclic antidepressant-maprotiline and anxiolytic-diazepam) (n=30) and non-psychiatric patients seeking prosthodontic treatment (control group, n=38). TMD were diagnosed by Research Diagnostic Criteria for temporomandibular disorders proposed by Dworkin and LeResche. The surface electromyography was recorded from left and right masseter muscles and masseter inhibitory reflex (masseter silent period) was recorded after mechanical stimulation. The incidence of TMD appearance was very similar, of approximately 40% in both group of patients. The results of the study also indicated a higher prevalence of joint related TMD, a lower prevalence of muscular subtype of TMD and a lower grade of chronic pain and related disability in the psychiatric group of patients on antidepressive therapy in comparison with findings in the control group. In the patients on antidepressive therapy with TMD masseter silent period was not prolonged , while in the control group of patients with TMD the prolongation of the silent period was observed. The study provided evidence that long-term, combined therapy (maprotiline and diazepam) in psychiatric depressive patients significantly modulated signs and symptoms of TMD in comparison with the control group.

CONFLICT OF INTEREST: NONE DECLARED Distance learning refers to use of technologies based on health care delivered on distance and covers areas such as electronic health, tele-health (e-health), telematics, telemedicine, tele-education, etc. For the need of e-health, telemedicine, tele-education and distance learning there are various technologies and communication systems from standard telephone lines to the system of transmission digitalized signals with modem, optical fiber, satellite links, wireless technologies, etc. Tele-education represents health education on distance, using Information Communication Technologies (ICT), as well as continuous education of a health system beneficiaries and use of electronic libraries, data bases or electronic data with data bases of knowledge. Distance learning (E-learning) as a part of tele-education has gained popularity in the past decade; however, its use is highly variable among medical schools and appears to be more common in basic medical science courses than in clinical education. Distance learning does not preclude traditional learning processes; frequently it is used in conjunction with in-person classroom or professional training procedures and practices. Tele-education has mostly been used in biomedical education as a blended learning method, which combines tele-education technology with traditional instructor-led training, where, for example, a lecture or demonstration is supplemented by an online tutorial. Distance learning is used for self-education, tests, services and for examinations in medicine i.e. in terms of self-education and individual examination services. The possibility of working in the exercise mode with image files and questions is an attractive way of self education. Automated tracking and reporting of learners’ activities lessen faculty administrative burden. Moreover, e-learning can be designed to include outcomes assessment to determine whether learning has occurred. This review article evaluates the current status and level of tele-education development in Bosnia and Herzegovina outlining its components, faculty development needs for implementation and the possibility of its integration as official learning standard in biomedical curricula in Bosnia and Herzegovina. Tele-education refers to the use of information and communication technologies (ICT) to enhance knowledge and performance. Tele-education in biomedical education is widely accepted in the medical education community where it is mostly integrated into biomedical curricula forming part of a blended learning strategy. There are many biomedical digital repositories of e-learning materials worldwide, some peer reviewed, where instructors or developers can submit materials for widespread use. First pilot project with the aim to introduce tele-education in biomedical curricula in Bosnia and Herzegovina was initiated by Department for Medical Informatics at Medical Faculty in Sarajevo in 2002 and has been developing since. Faculty member’s skills in creating tele-education differ from those needed for traditional teaching and faculty rewards must recognize this difference and reward the effort. Tele-education and use of computers will have an impact of future medical practice in a life long learning. Bologna process, which started last years in European countries, provide us to promote and introduce modern educational methods of education at biomedical faculties in Bosnia and Herzegovina. Cathedra of Medical informatics and Cathedra of Family medicine at Medical Faculty of University of Sarajevo started to use Web based education as common way of teaching of medical students. Satisfaction with this method of education within the students is good, but not yet suitable for most of medical disciplines at biomedical faculties in Bosnia and Herzegovina.

OBJECTIVE The purpose of this study was to survey image quality and the entrance surface air kerma for patients in radiographic examinations and to perform comparisons with diagnostic reference levels. SUBJECTS AND METHODS In this multinational prospective study, image quality and patient radiation doses were surveyed in 12 countries in Africa, Asia, and Eastern Europe, covering 45 hospitals. The rate of unsatisfactory images and image quality grade were noted, and causes for poor image quality were investigated. The entrance surface doses for adult patients were determined in terms of the entrance surface air kerma on the basis of X-ray tube output measurements and X-ray exposure parameters. Comparison of dose levels with diagnostic reference levels was performed. RESULTS The fraction of images rated as poor was as high as 53%. The image quality improved up to 16 percentage points in Africa, 13 in Asia, and 22 in Eastern Europe after implementation of a quality control (QC) program. Patient doses varied by a factor of up to 88, although the majority of doses were below diagnostic reference levels. The mean entrance surface air kerma values in mGy were 0.33 (chest, posteroanterior), 4.07 (lumbar spine, anteroposterior), 8.53 (lumbar spine, lateral), 3.64 (abdomen, anteroposterior), 3.68 (pelvis, anteroposterior), and 2.41 (skull, anteroposterior). Patient doses were found to be similar to doses in developed countries and patient dose reductions ranging from 1.4% to 85% were achieved. CONCLUSION Poor image quality constitutes a major source of unnecessary radiation to patients in developing countries. Comparison with other surveys indicates that patient dose levels in these countries are not higher than those in developed countries.