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The paper is divided onto four major parts. In the introductory part the author states that personal evidence (statements of whiteness, suspect, accused, convicted and expert) play still a very important role in collecting evidence in criminal procedure, even though the significance of physical evidence is growing. In the second part the classical model of interrogation is presented, which is based on the division of interrogation onto three parts. This model is accepted by majority of authors. The third part is devoted to alternative models. The fourth part contains concluding remarks. Here the author underlines that scientific novelties are valuable only if they contribute to the practice, and this contribution is only possible if the interrogators are trained adequately and if objective conditions for the application of the novelties are provided. [ABSTRACT FROM AUTHOR]

This paper developed a mathematical model of gas dynamic fluid flow for a flat plate during its movement with positive and negative angles of attack. It is shown that at low velocities, the lifting force and the frontal resistance are determined by gasdynamic air flow in the fluid flow exit areawhile at velocities close to the speed of sound the decisive role is played by a mutualeffect of the pplate coliding with molecules of the surrounding environment in the fluid flow incidence field. The airflow behind the plate does not appear at low velocities. The conditions when the frontal resistance and the lifting force change the sign are determined. [ABSTRACT FROM AUTHOR]

Chaotic spreading sequences can increase secrecy and resistance to interception in signal transmission. Chaos-based CDMA systems have been well investigated in the case of flat fading and noise presence in the channel. However, these systems operating in wideband channels, characterized by the frequency selective fading and white Gaussian noise, have not been investigated to the level of understanding their practical applications. This paper presents a detailed mathematical model of a CDMA system based on chaotic spreading sequences. In a theoretical analysis, all signals are represented in the discrete time domain. Using the theory of discrete time stochastic processes, the probability of error expressions are derived in a closed form for a multi-user chaos based CDMA system. For the sake of comparison, the expressions for the probability of error are derived separately for narrowband and wideband channels. The application of the system interleaving technique is investigated in particular, which showed that this technique can substantially improve probability of error in the system. The system is simulated and the findings of the simulation confirmed theoretically expected results. Possible improvements in the probability of bit error due to multipath channel nature, with and without interleavers, are quantified depending on the random delay and the number of users in the system. In the analyzed system, a simplified version of the wideband channel model, proposed for modern wideband wireless networks, is used. [ABSTRACT FROM AUTHOR]

This paper describes models and conditions for the application of the Mass Serving Theory in order to analyze relations between clients demanding the service and channels which provide the service as well as to design technological elements in the optimal regime for the given maintenance system. Based on the actual data collected and the statistical analysis of the expected intensity of combat vehicle arrivals and queuing at service for technical maintenance, the mathematical modeling of a real process of queuing was carried out and certain parameters quantified, in terms of determining the weaknesses of the existing models and the corrective actions needed. [ABSTRACT FROM AUTHOR]

Various organizational structure options are proposed in the application of the given model, taking into account the fact that transport authorities should be designed and dimensioned so as to achieve the rudimentary goals and tasks for fulfillment of which they were established. Each task set before the transport authorities requires a reliable and top-quality performance in all environmental conditions. Since most of the acquired data is characterized by a high degree of imprecision, subjectivity and uncertainty, fuzzy logic was used for displaying these. Fuzzy linguistic descriptors were used for describing the criteria used for evaluating the proposed alternatives. In this way, fuzzy logic enables the exploitation of tolerance that exists in imprecision, uncertainty and partial truth of the acquired research results. The paper presents a model for designing the organizational structure of transport support authorities. [ABSTRACT FROM AUTHOR]

Background/Aim. Medial open wedge tibial osteotomy is one of the most widely accepted method of treatment for varus knee deformity in younger patient population. Its success depends on the quality of fixation and preservation of the outer cortex of the tibia. The aim of the study was to evaluate stress distribution in five numerically designed plate configurations which can be used in open wedge tibial osteotomy. Methods. The paper describes the 3D numerical model of the tibia with 10° varus deformity correction obtained by an optical scanner ATOS. The simulation anticipated axial compressive loads of 700 N, 1 400 N and 2 100 N. We used a modification of the standard T-plate in all of the five tested models. Modalities were tested with and without a metal block, and with and without a stable angle fixation plates and screws. Software PAK was used in the analysis of stress distribution. Results. With exception for the standard T-plate configuration without the supporting block, the loads up to 1400 N did not result in critical stresses on the outer cortex of the tibia in the remaining four models. There is an objective risk of possible failure of the outer cortex and loss of correction at a load of 2100 N in all configurations. The plate model with the angle stable fixation and the supporting metal block showed the most optimal distribution of stresses on the plate-bone composite compared to other models. Conclusion. The standard T-plate configuration without supporting metal block is not sufficient to stabilize the open wedge osteotomy of the tibia. Numerical models of the angle stable T-plate and the supporting metal block achieved a favorable distribution of stresses on the bone and implant which require further biomechanical testing. [ABSTRACT FROM AUTHOR]

This work represents scientific and expert analisys of data colected on project and programms that deal with student safety and security of schools in period since 2000 onwards, which were financed and supported by two key institucion deeling with youth. Those two institutions are Ministry of Education and Ministry of Youth and Sport, which is after passing Nacional Youth Strategy supported many projects that deal with the youth problems. The text has been made with the purpose to isolate key element for the presentation and analysis of projects and programs realized and which realization is still in progress in the Republic of Serbia, and then to give a critical evaluation of each one in order to come to an optimal model and programs to protect security of schools in the Republic of Serbia, which is the purpose of the project. First of all, named criteria used for selection of projects that will enter the field of analysis and presentation, and then the criteria or parameters by which we evaluate the pros and cons of each. The following text is part of Faculty of Security Studies financed by Ministry of Education and Science of the Republic of Serbia named by „Safety and Protection of Organization and Functioning of Educational System in Republic of Serbia“. [ABSTRACT FROM AUTHOR]