Applied Mechanics and Materials Vol. 822

Abstract: The paper presents a method which combines experimental and theoretical approach, to derive an expression for estimating the power of thermal source in a turning process. This method uses a finite element mesh overlapped on infrared images (obtained from the cutting process), in order to extract the nodal temperatures corresponding on. A reverse formulation for a finite element analysis is used, knowing the nodal temperatures and boundary conditions, and deriving the thermal load which produces the measured thermal distribution. This experiment has concentrated to allied steel.

Abstract: This paper presents an economic model based on graph theory to optimize the execution order for automotive products on the manufacturing lines served by robots, so that the total manufacturing cost is minimized. The starting point is a representation of the range of automotive products with similar design attributes but with different construction requirements (material, tolerances, production volume). This representation is distinguished by a directed graph G = (X, Γ) consisting of the set X of nodes (products) and the set Γ of arcs (paths with minimal cost). In terms of mathematical optimization problem is solved by determining the minimum length Hamiltonian path in the graph, using the algorithm of Foulkes. The length of a path is obtained by adding the numbers associated with that path arcs. The model can be applied to other extreme transportation issues CIM type, such as: transportation network modeling; determining minimum distances; median problem (placing checkpoints); multi-product maximum flow problem.

Abstract: Adaptive traffic signal control is the process by which the timing of a traffic signal is continuously adjusted based on the changing arrival patterns of vehicles at an intersection, usually with the goal of optimizing a given measure of effectiveness. In this paper a traffic signal program is developed in which the characteristics of a traffic signal cycle are optimized at the conclusion of every phase based on the arrival times of vehicles to an intersection, using stopped delay as the measure of effectiveness. The methodology which leads to the signal plan is shown to provide improvement in performance for a number of intersection configurations and traffic regimes over traditional forms of traffic signal control.

Abstract: Recent statistics on the main causes of road traffic accidents and subsequently the main causes of victims’ injuries which may ultimately lead to fatalities, indicate that within urban areas the first place is occupied by prohibited road-crossing, accounting for over 20% of the causes for road traffic accidents. Hence, one of the major direct consequences arising is the severe injury of the pedestrians-up to their fatalities-due to prohibited road crossing through unauthorized places. Thus, the present paper underpins a research study on the vehicle-pedestrian collision, based on a statistical analysis of the pedestrian model, most frequently involved in road traffic accidents. The statistical analysis will be then reinforced by a theoretical study regarding this type of collision. In order to validate the mathematical model, applied to determine the projection throw distance of a pedestrian, we have also proposed a virtual simulation of the vehicle - pedestrian collision, described within the last section of the present research paper.

Abstract: Biomechanics is the science that uses mechanical equations in studying biological structures such as bones, muscles, ligaments, joints and other body structures. It is important in understanding the mechanism of injury to the cervical spine (C1-C7) and head bones. We developed a mathematical approach to mechanical behavior of cervical vertebrae and inter-vertebral discs, in terms of laboratory testing. The paper presents the mathematical model based on Lagrange equations for a frontal impact testing head-neck system. The steps for the solving these equations are exposed in the paper. These studies were combined with FEA and dynamic analysis for determination of constants,parameters, forces and functional relations. Results and conclusions were analyzed in the final of the paper.

Abstract: In this paper it is presented a way of optimizing a public passenger transport route from Targu Jiu city. It was analyzed the current conditions of public passenger transport, measurements were carried out on the route and questionings of passengers used to establish input data for optimization. The most important result of this optimization is to establish an optimal distance between stations on the analyzed route away to ensure a minimum time of the passengers traveling at acceptable commercial speed and driving conditions imposed by Tg. Jiu city specific.

Abstract: Need for transport accelerated growth recorded in the past years results in worsening road congestion phenomenon, with negative effects in all domains of life. Thus, some road junctions’ capacity is exceeded during peak hours and traffic lights are not effective any more. In these situations, modifications to infrastructure or/and changes in the local policy plan are required. However, these cannot be performed immediately and remain rather a solution that will operate later. The authors attempt to find out a satisfying semaphoring scheme for these time slices, outlining the effects.

Abstract: In many cases we have to estimate the speed of the vehicles involved in an accident. The aim of this paper is to make a brief presentation of some cases solved on the question of speed and dynamics using different methods and presenting the estimated error obtained. So in the paper it will be taken into account the indication of tachograph diagram with pro and contra arguments assuming that this indication is only informative as far as the tachograph is not specially designed as an accident recorder device. In the paper it will be included the reconstruction of the accident using PC Crash facility in optimization method to reduce the error regarding the trajectory and rest position. For validation of this analysis we will provide also a video surveillance camera film high resolution versus simulation of the accident. Keywords: accident reconstruction, simulation, optimization.

Abstract: In most of the cases of a road traffic accident reconstruction, the usage of traditional reconstruction methods represents the basic set of tools, but in an ever increasing number of cases, computer simulation is used for control the results or vice versa. In some cases, traditional methods, based on linear momentum conservation, energy conservation and assessment of deformation of the vehicles or experimental results of crash tests are not suitable because of the highly unusual character of the collision. The paper deals with one case of this type in which the pedestrian was cut in two parts.

Abstract: In this paper is presented the analysis of the behavior of occupants inside a vehicle during road events, methods and means of biomechanics. Also, to analyze the behavior of the occupants were taken into account research methods impact occupant kinematics, based techniques for acquisition and processing of experimental data.