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Identification of Relevant Tire Traces in Traffic Accident Place Based on their physical characteristics
Bilík, Martin ; Kovanda, Jan (referee) ; Kledus, Robert (referee) ; Bradáč, Albert (advisor)
The thesis deals with the possibilities of identifying the relevant tire traces at the place of a traffic accident based on their physical characteristics. Braking traces on the road are one of the most important objective elements for accident analysis, their easy and accurate detection is very important for accurate accident assessment. With the increasing technical equipment of vehicles, especially with the introduction of newer generations of braking assistance systems, traces left by the tires become almost invisible to the human eye. It is therefore highly desirable that their detection should be not only as accurate as possible but also as easy and fast as possible, not only for forensic experts, but especially for members of the traffic police departments. In line with the development and introduction of new safety and assistance systems for vehicles should also be the development of means and methods of providing the basis for technical analysis of traffic accidents. Reality shows that the procedures, even if still functional, are practically identical for several decades, are dependent on the subjective capabilities of the documenting person. An essential element of the work, compared to the previously described measurement procedures, is the use of modern methods and devices at the highest known level of knowledge. The aim is to find and verify a simple, accurate, subjectively least influenced detecting method for tire traces on the road. A series of measurements confirmed the possibility of using the thermal camera at the technical level usually available at the place of the accident, under limited atmospheric and time conditions. In addition, laser-induced plasma spectroscopy and rLIBS were used. This method of detecting spotless tire treads can be marked as a minimally feasible documentary and at the same time as fast enough, based on the measurements made and the intended removal of defects of the instrument in the development phase of the prototype.
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Analysis of set of factors affecting safe longitudinal distance between vehicles
Zemánek, Lukáš ; Kovanda, Jan (referee) ; Bradáč, Albert (referee) ; Vémola, Aleš (advisor)
The doctoral thesis deals with problems of a safe longitudinal distance between vehicles. It includes an analysis of a set of factors influencing the safe distance between vehicles and is concerned with a research of effect of many of these factors on observance of the safe longitudinal distance between vehicles. In connection with these factors, this work deals with the solution of this issue in neighbouring countries through statutory measures, then with statistical analysis of traffic accidents in the Czech Republic caused by non-observance of the safe distance, also problems of assistance systems operating in this area, and subsequently, based on the findings, there are recommended suggestions of actions to increase safety in this area of road transport.
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Compatibility of Vehicles in a Frontal Collision
Vašíček, Jiří ; Kovanda, Jan (referee) ; Coufal, Tomáš (advisor)
Thesis deals with the compatibility of vehicles in a frontal collision. The first section discusses about compatibility from different views. There are the physical processes used in the mechanics of impact. The second part is focused on solving the compatibility of vehicles in a frontal collision by crash analysis using the finite element method. Firstly there are described collisions of vehicles from different vehicle classes (small cars, lower middle class, Pick up / SUV) into the fixed barrier by the US NCAP. Furthermore there are simulated head-on collisions of vehicles from different vehicle classes. In the end there is shown the possibility of using data from crash tests to determine the EES.
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Analysis of impact of active safety elements in vehicles on pedestrian protection for traffic accident investigation
Vertaľ, Peter ; Kovanda, Jan (referee) ; Kropáč, František (referee) ; Vémola, Aleš (advisor)
Increase the probability of prevent road accidents by installing autonomous systems in a vehicles is the current trend in the field of active safety with a focus on pedestrian safety. The work deals with the evaluation of intervention of active safety systém for pedestrian detection assembled in series production. Benefit of active safety systems to prevent road accidents can be achieved, for example, early warning driver of a potential collision situation sufficiently in advance to reaction and post-maneuver (braking, yaw, ..). The evaluation of the intervention of active safety systems, which aim to prevent an accident with a pedestrian is necessary to experimentally evaluate the behavior of these systems. The main objective of this work is to test the selected systém based on different types of reál accidents. Atthe time of the measurements and present, are not for experts and specialists in the field of road traffic accidents publicly accessible data about the behavior of such a systém. The work aims to evaluate the behavior of the Volvo systém in inducing reál traffic situations. For the evaluation of this systém are precisely analyzed fatal traffic accidents with pedestrians in the urban area (speed of vehicles up to 60 km/h). Simulated traffic situations by their nature cover the most common critical situations in urban traffic. Expert community and the professionals who deal with the solution of traffic accidents receive this work valuable data to deal with such accidents. Based on these measurements give more expert input data to solve a collision with a pedestrian. The basis for understanding the behavior are created graphs of distance, speed and time at a key moment of the collision. These key moments include entry a pedestrians to driving corridor of the vehicle, system's response to conflict situations, warn the driver and then autonomously brake active safety systém
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STIFFNESS ANALYSIS OF FRONT PART OF THE VEHICLE
Coufal, Tomáš ; Kovanda, Jan (referee) ; Kohút,, Pavol (referee) ; Vémola, Aleš (advisor)
The thesis deals with the front part stiffness of modern vehicles, especially for the use in the field of forensic engineering in the traffic accident analysis. During the traffic accident analysis, an inquiry into the collision between vehicles is carried out which is an integral part of determining the energy loss of the vehicle at the impact, or more precisely the deformation energy expressed in the form of Energy Equivalent Speed (EES). In case of known stiffness of given part of the vehicle and based on the depth of deformation, it is possible to calculate the deformation energy, or more precisely EES corresponding with given damage of the vehicle. In the field of forensic engineering, the values of stiffness of individual vehicle components are not known and therefore, alternative methods are used to calculate the EES, they are outlined in the research part of this dissertation. However, the current methods of EES determination have some limitations when it comes to usability, and therefore, new EES calculation for the front part of the vehicle was designed in the research. It was based on the real crash test results using real stiffness characteristics of the front part of a vehicle. The front part of the vehicle is divided into individual areas and each of these parts is characterised by its own stiffness coefficient. The designed EES calculation can thus be also used for collisions with partial overlapping, taking into account the real stiffness of the damaged part of the vehicle, which was not possible with existing methods. In the research part of this dissertation, a computer programme to calculate deformation energy and EES was processed. It works with individual stiffness characteristics in given areas where the input data are entered by the user and include the depth of permanent front part deformation in individual areas, vehicle weight, the direction of an impact force and the friction coefficient on the contact surface. Considering the fact that the vehicle stiffness is also one of the control parameters at solving collisions in the PC-Crash simulation programme, which is used in forensic engineering practice for the analysis of a collision process, a supplementary computer programme was designed. Based on the above-mentioned input data, the supplementary programme can further calculate data for collision solving in the simulation programme, namely stiffness, restitution coefficient and the vehicle damage stated in the output report of the simulation programme. Based on these data, the expert thus has the opportunity to solve the collision of two vehicles in the simulation programme with as much preciseness as if it was a real collision.
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Pathophysiological and clinical aspects of cardiac dyssynchrony in children and adolescents
Kovanda, Jan ; Janoušek, Jan (advisor) ; Bulava, Alan (referee) ; Klásková, Eva (referee)
Pathophysiological and clinical aspects of cardiac dyssynchrony in children and adolescents Electromechanical dyssynchrony is an important factor in the development of heart failure. It is caused by abnormal activation of the working myocardium in case of bundle branch block or ventricular pacing. Asymmetric hypertrophy of the affected ventricle develops together with its dilatation and reduced function and fulfils the picture of dyssynchronous cardiomyopathy. The development of dyssynchronopathy can be prevented by careful selection of the permanent pacing site and treated by cardiac resynchronization therapy. One of the aims of this work was to compare clinical and echocardiographic findings in patients paced from the left-ventricular apex with the healthy population. Using a retrospective cross-sectional study, we have proved that left ventricular function is not adversely affected in long-term follow-up. Another aim of the study was to evaluate the long-term results of resynchronization therapy of the systemic ventricle in patients with congenital heart defects. Using a retrospective study, we have described an acceptable long-term survival at the price of relatively frequent complications. We were extensively working on a new method of resynchronization of the right subpulmonary ventricle in...
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The possibilities of evaluation of the sport performance on the postural functions - CDP normative data for sport population
Vomáčková, Helena ; Pavlů, Dagmar (advisor) ; Kovanda, Jan (referee)
I ABSTRACT Autor: Mgr. Helena Vomáčková Title: The Possibilities of Evaluation of the Sport Performance on the Postural Functions - CDP Normative Data for Sport Population Objective: The main aim of the dissertation is to determine the standardized values (normative data) of individual parameters of test protocols obtainable with usage of dynamic computer posturography of the NeuroCom SMART EquiTest System (hereinafter SMEQ). The partial second goal is to compare the determined normative data with the existing values used for routine evaluation of postural stability given by the SMEQ software. Another partial goal is to determine the reliability of individual test parameters in an additional pilot survey. Methods: Data for the determination of standardized values were obtained by laboratory measurements using the SMEQ system and subsequently were converted, unified and adjusted for further processing by statistical "software R". To determine the normative data, an input data-set obtained from a deliberately selected group of active athletes (n = 245) in the selected age range of 20 - 30 years with an average age of 24,04 (± 1,23 years), with an average body height of 173, 29 (± 10,04 cm), mean body weight 68,46 (± 13,10 kg) and mean BMI 22,67 (± 3,04) was used. To calculate the predicted normative data for...
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THE BIOMECHANICAL REFLEXION OF MODERATE IDIOPATHIC SCOLIOSIS IN GAIT CYCLE OF YOUNG ADULTS
Polyzos, Christos ; Kovanda, Jan (advisor) ; Pavlů, Dagmar (referee) ; Rosenberg, Josef (referee)
Introduction: Scoliosis influences the optimal posture and locomotion of the human body. Lumbar and thoraco-lumbar scoliosis has possibly an even greater impact due to the close relation with the pelvic region, a major determinant of gait. The effect of moderate idiopathic scoliosis on the gait cycle of young adults is of major interesting. Discussion-Hypothesis and aims: Young adults (20-40 years old) with MIS (lumbar and thoraco-lumbar primary curves) present kinematic modifications regarding the convex (ipsilateral extremity) or concave (controlateral extremity) side of the body as well as variations compared to non-scoliosis individuals during the gait cycle. Aim of this study was to indentify these variations on the physical quantities exerted from the major joints of the lower extremities as well as the center of gravity too and examine their significance in adult patients with MIS. Materials and methods: A cohort of twenty young adult patients (group A, 12 females- 8 males, mean age 39,7 years) having MIS with mean Cobb's angle 29o (24o to 34o ) and a control group (B) of fifteen (8 females, 7 males) of healthy individuals were submitted in clinical examination and 3-D gait analysis. Direct linear transformation (DLT) was used for analysis of linear displacement on the three axes (x, y and z) as well...
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Detection of head biomechanical response during extreme loading
Fanta, Ondřej ; Jelen, Karel (advisor) ; Kovanda, Jan (referee) ; Hynčík, Luděk (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Physical Education and Sport Dissertation thesis March 2014 Ondřej Fanta ABSTRACT Title: Detection of head biomechanical response during extreme loading Objectives: The aim of the work was to monitor the current state of knowledge on the issue of closed head injuries, in contact and contactless respectively impacts, to establish appropriate biomechanical indicators for the detection and analysis of internal mechanical response under external mechanical load and to assess the specific circumstances that may affect the resulting injury criteria especially with regard to the actual reaction of the organism before impact. Methods: To the processing research were included and cited in particular impacted world-class publications and bibliography in the number of more than 80sources. The measurements and analysis of contact impacts were taken on the constructed impactor and the analysis of the contactless collisions were taken on the impacts simulator. The monitored biomechanical values were in particularly kinematic data describing the movement of the head towards the neck, values of acceleration of the head, head injury criteria and activity of selected muscles of the neck. Results: It consists diagram of the process of head injury and analysis of two main branches -...
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