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The paper analyzes the possibilities of using computer aided modelling programs for developing new cars to achieve better dynamical properties of control over vehicles. The article shortly reviews the behaviour of young and experienced drivers and models describing it. The paper covers the process of turning car steering wheel, considers acceptable values of lateral acceleration comfortable for a car driver and all car passengers and presents computer aided modelling program CarSim used for displaying single and double lane change manoeuvres at various speeds on dry asphalt. The given charts, including data about steering wheel angle and lateral acceleration values indicate single and double lane change manoeuvres performed by a car. Also, the values of longitudinal and lateral forces of each wheel during the double lane change manoeuvre are provided. [ABSTRACT FROM AUTHOR]

Different types of planar broadband slow-wave systems are used for designing microwave devices. The papers published by Lithuanian scientists analyze and investigate the models of helical and meander slow-wave systems. The article carefully examines the applications of meander slow-wave systems and presents the areas where similar systems, e.g. mobile devices, RFID, wireless technologies are used and reviewed nowadays. The paper also focuses on the examples of the papers discussing antennas, filters and couplers that contain designed and fabricated meander slow-wave systems. [ABSTRACT FROM AUTHOR]

The article concerns the thematic of evaluation in public management. The purpose of the paper is to analyze the conception and the models of evaluation in public management. There is a study of different types of evaluation approaches and evaluation definitions in the paper, which indicates the idea that there is no common definition of evaluation in public management, because it is strong in the context. Moreover, the implication of evaluation depends on such criteria as evaluation needs, evaluation purpose, typically applied methods, the role of evaluator and others. The paper also provides a discussion on the evaluation in historical perspective and the classification of evaluation models. The article identifies and describes the main evaluation models such as politically controlled studies, objectives orientated evaluations, management information systems, decision orientated evaluations, etc. [ABSTRACT FROM AUTHOR]

The article deals with a problem of experimental investigation and numerical simulation of gas aerodynamics of a multi-channel spiral cyclone with a tangential inlet. The paper presents an overview of experimental and theoretical works on the cyclones having a particularly complex turbulent flow and focuses on three-dimensional transport differential equations for a non-compressible laminar and turbulent flow inside the cyclone. The equations have been solved applying the numerical finite volume method using the RNG (Re-Normalisation Group) k-ε turbulence model. The numerical simulation of the flow cyclone has been carried out. The height of the cyclone is 0.80 m with 0.33 m in diameter, the height of the spiral-cylindrical part -0.098 meters and that of the cone - 0.45 m. Inlet dimensions (cylindrical part on the side), in accordance with drawings makes axb = 28x95 mm. The mathematical model for the air traffic movement cyclone has accounted for Navier-Stokes (Reynolds) three-dimensional differential equations. The simulation results have been obtained with reference to the cyclone of tangential velocity profiles using RNG k-ε turbulence model. The inlet velocity of 5.1 m/s slightly differs from experimental results, thus making an error of 7%. [ABSTRACT FROM AUTHOR]

The article deals with pneumatic muscle MAS-20-200N-AA-MC-O, its dynamic properties and positioning accuracy as well as overviews experimental and theoretical works. The paper introduces the diagrams of vibration acceleration, discusses displacement dependence on pressure and load and presents a diagram of speed dependence on operating pressure. Vibroacceleration has been measured employing two accelerometers. Measurements have been carried out in three mutually perpendicular directions: x, y and z. The most important one is direction z, because this way the muscle performs a valuable displacement along the axis of the muscle, since this direction is the movement of the working muscle. [ABSTRACT FROM AUTHOR]

The paper presents modelling precise dual axis flexure-based precision positioning systems for micro-positioning applications. The positioning system is featured with monolithic architecture, flexure-based joints and piezo stacks. Its workspace has been evaluated via analytical approaches. Amplification mechanism is optimally designed. The mathematical model of the positioning system has been derived and verified by resorting to finite element analysis (FEA). The established analytical and (FEA) models are helpful for optimizing reliable architecture and improving the performance of the positioning system. [ABSTRACT FROM AUTHOR]

The paper examines the models and stiffness efficiency of the column base of semi-rigid steel frames, reviews stiffness calculation methods and calculates the rotation of cohnnn base connection in two ways: analytical, according to LST EN 1993-1-8, and finite element, applying nonlinear analysis. Two groups of modelling have been made: the first group deals with changes in the thickness of the base plate; the second one shows a different diameter of the anchor bolt. The obtained results reveal the influence of the base plate and anchor bolt on the stiffness of column base connection. The article discusses differences in the euro code and linear analysis: minimum difference makes 61,6% and maximum - 73,7%. For calculating the strength of the column base, a conservative model has been employed, i.e. according to the Eurocode, the received values are smaller compared to nonlinear analysis: minimum difference makes 37,0% and maximum - 49,0%. [ABSTRACT FROM AUTHOR]

Artificial neural networks (ANN) have recently gained attention as fast and flexible equipment for modeling and designing microwave devices. The paper reviews the opportunities to use them for undertaking the tasks on the analysis and synthesis. The article focuses on what tasks might be solved using neural networks, what challenges might rise when using artificial neural networks for carrying out tasks on microwave devices and discusses problem-solving techniques for microwave devices with intermittent characteristics. [ABSTRACT FROM AUTHOR]

Paper presents examination of induction motor stator windings currents harmonics, when modulation index and carrier frequency are changed. Mathematical model of symmetrical induction motor connected as star without zero wire is developed. Matlab Simulink models are created and tested. [ABSTRACT FROM AUTHOR]

This paper presents a model of a precise dual axis flexure-based positioning system for micro-positioning uses. The positioning system is featured with monolithic architecture, flexure-based joints and ultra fine adjustment screws. Its workspace has been evaluated via analytical approaches. Reduction mechanism is optimally designed. The mathematical model of the positioning system has been derived and verified by resorting to finite element analysis (FEA). The established analytical and (FEA) models are helpful for reliable architecture optimization and performance improvement in the positioning system. [ABSTRACT FROM AUTHOR]