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Traumatic consequences of pedestrian - tram interaction and specifics in the case of child - pedestrians
Belková, Natália ; Jelen, Karel (advisor) ; Tlapáková, Eva (referee)
Title: Traumatic consequences of pedestrian-tram interaction and specifics in the case of child-pedestrians Objectives: The aim of the paper is to analyze the issue of pedestrian-tram traffic accidents in respect of injury consequences, based on available literary sources in accordance with the selection criteria. Special attention is paid to where such accidents involve children. The work is part of the grant ANALYSIS OF ACCIDENT EVENTS CHODEC TRAMVAJ. It aims to evaluate the occurrence, type and nature of injuries where collisions have taken place between pedestrians and trams. Methods: The thesis is produced on the basis of literary research. Due to the breadth of the interdisciplinary nature of the issue, literary sources were searched in the NCBI, Sciencedirect, Springerlink, Researchgate, PubMed databases. The first part of the thesis contains a theoretical introduction to the issue of tram transport and the definition of basic concepts, injuries of individual parts of the locomotor system and accident mechanisms in terms of biomechanics. The second part has a descriptive-analytical nature and contains an analysis of individual studies that deal with the health of a pedestrian/child accident, in relation to a tram. Results: At the end of the search, 64 studies met the selection criteria. Six...
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Identification of changes in mechanical characteristics of human axial system as a result of loading and relaxation regime
Van der Kamp Kloučková, Kateřina ; Jelen, Karel (advisor) ; Maršík, František (referee) ; Rosina, Jozef (referee)
Problem: A lot of attention is given to the safety of the driving and the possibility to register fatigue of the drivers. Driving cars is monotony and static. Vibration loading, which causes changes in the axial system. This causes discomfort and fatigue to drivers after some time of exposure to the loading. Hypothesis: It is possible to prove the changes of mechanical characteristics (indicators) of the axial system using the TVS (transfer vibration through spine) method. By using TVS method before and after different types of loading or before and after relaxation it is possible to detect changes of the viscoelastic properties. This can be done by checking changes in the way of waves transfer through the axial system of the observed participants. Objective: Verify the possibility of use of TVS method to register changes of the viscoelastic characteristics of the axial system. Method: The TVS was chosen as a detection method. The method is based on the use of five-msec semi-bandwidth γ pulse stimuli and consequent application of continuously changing harmonic stimuli which periodically differ between 5Hz and 160Hz to the vertebrae C7 and L5. This wave is carried through the axial system and its acceleration on the spinous processes between C7 and S1 is scanned with the help of accelerometric...
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The rheological response to a history of knee joint loading
Prokešová, Michaela ; Otáhal, Stanislav (advisor) ; Jelen, Karel (referee) ; Vilímek, Miloslav (referee)
Title: The rheological response to a history of knee joint loading Aim: The purpose of this work is to illustrate the possibilities of rheological interpretation of passive resistance in the knee joint during simple forced movement of the knee flexion and extension in the sagittal plane. Methods: With the help of biorheometrical measurements, we identify the effect that a weight bearing history has on the actual rheological properties of the knee joint. The methods are based on an experiment carried out in vivo, passive momentum (resistance) of the knee joint during forced flexion and extension are measured and expressed as the specific rheological response of the knee joint. The dependence of passive momentum M on the angle of flexion φ is hereby characterized as the total rheological characteristic of passive forces on the whole knee and its surroundings. The graphical interpretation of the duration of the momentum force is named - biorheogram. Result: Results of experimental study presented in this dissertation distinctly shows that rheologic interpretation of passive resistance in the knee joint during simple forced movement of the knee joint in the sagittal plane is possible in flexion and extension. Conclusion: Rheologic description of hysteretic response of passive resistance {moment of...
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Biomechanical response of selected structures of the knee joint to mechanical loads
Horňáková, Lenka ; Jelen, Karel (advisor) ; Navrátil, Leoš (referee) ; Mlynárik, Vladimír (referee)
Title: Biomechanical response of the knee meniscus to the axial loads Work Title: The quantification of the structural changes in deep layer of the knee meniscus using the standardized axial loading Purpose: Due to the internal structure of the knee joint, the ability to characterize and quantify the dynamic response of the meniscal tissue directly in vivo is highly problematic. The main purpose of this study was to investigate the behavior of the meniscus under loading conditions, using parametric MR imaging. Methods: Subjects with no history of knee pain or meniscal problems were included in the study (mean age 27.8 ± 1.3 years). To obtain values of relaxation times T2* in the meniscus, the vTE sequence was used with 10 echoes ranging from 0.8 to 10.1 ms. This has resulted in minimizing the echo time, which is an advantage when differentiating meniscal tissue from surrounding components. First of all, an unloaded limb was scanned and immediately after, the limb loaded half of the person's weight was measured repeatedly in 4 consecutive scans. A custom - made diamagnetic apparatus was developed to simulate stress conditions on the lower limb in a conventional MR scanner. At each 6:10 min measurement, the knee joint was scanned in 64 sections, each image displaying a 1.3 mm section.The two -...
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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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Myodynamics of the support phase during different take-off tasks in human locomotion
Hojka, Vladimír ; Jelen, Karel (advisor) ; Otáhal, Jakub (referee) ; Kampmiller, Tomáš (referee)
Title: Myodynamics of the support phase during different take-off tasks in human locomotion Objectives: Six types of take-off movement were analyzed in terms of support limb kinematics, take-off dynamics and muscle activation, in order to identify differences in motor control. Methods: 14 male athletes (22.6 ± 4.4 years; 182.4 ± 5.3 cm; 74.7 ± 6.2 kg) took part in laboratory experiment. Each athlete performed six different take-off movements (running, acceleration - first and second step, long jump take-off, high jump take-off and take-off to the hurdle). System Qualisys was used to analyze kinematics of the support limb. Dynamic of the suport phase was measured with Kistler 9281 EA force- plate. ME6000 apparatus was used to measure the muscle activation. Results were processed and statistically evaluated in Matlab (MathWorks, Inc) environment. Pair ANOVA, T-test and Friedmann test were performed to identify differences between take-off movements. regression analysis was introduced to find the relationship between parameters. Results: Significant differences in take-off dynamics are realized with not so significant differences in kinematic and electromyographic parameters. high jump and long jump take-offs acted most specifically in comparison with other types of take-offs. Two typically...
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Measurement of loading forces on sole of the foot in ice-hockey skates and their casuistic mean
Šťastný, Petr ; Jelen, Karel (advisor) ; Kračmar, Bronislav (referee) ; Vaverka, František (referee)
Title: The measurement of loading forces acting on sole of the foot in ice-hockey skates and their casuistic signification Abstract This thesis describe a new construction of measuring device, which is able to detect the loading forces acting on the skates during ice-hockey. This device was calibrated and validated for detection of loading force vector, bending force vector and point of force action on the skate blade. For some cases was described a casuistic mean of measurement by new measuring device "measuring skates" and former device Footscan Insole®. The measurement of loading forces during ice-hockey may be used in practise of skating technique, predictive or protective biomechanics. Future use is also research of discomfort in ice-hockey boots or sportsengeneering. Aim of a study: Aim of a study is projected, calibrated and validated a measuring device able to detect interraction in system foot-skates-surface. After validation is neccessary to prove the practical benefit of this device. This device should make possible to find out the origin of discomfort during ice-hockey skates use. Methods: After a critical review the prototype of measuring skate was constructed. The measuring skate was calibrated a nd validated. In contend of pilot study was done the experiment to proof the casuistic mean of...
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Changes in the mechanical parameters of women's hair during pregnancy
Skřontová, Marie ; Jelen, Karel (advisor) ; Tlapáková, Eva (referee) ; Berchová, Kateřina (referee)
Title: Changes in the mechanical parameters of women's hair during pregnancy Matters: We can look from different angles on the hair - as on a nanocomposite fiber and as on biomaterial changing with the origin and age. The hair doesn't differ only by lenght, stucture and color but also by diameter and shape. It reflects the overall health of the individual and all the processes in the organism of the individual and thus also the pregnancy. During pregnancy, hormonal changes take place which have an effect on the hair. Many women experience faster hair growth, extension and increased volume of the hair during pregnancy. This status is only temporary and lasts only to the childbirth. Aim: The aim of this work was to show the influence of pregnancy on mechanical parameters of hair and what direction this influence takes. Next, using questionnaires, to better solve the effect of particular pregnancy parameters on the hair, i.e. pregnancy order, sex of the child. Then, evaluate the whole problem using statistical tests and so make better sense of it. Methods: We'd selected a group of 64 pregnant women; hair samples were cut from them in the nape area each month throughout pregnancy. Each measurement started with evaluation of hair diameter with the use of optical microscope. Next, the hair had been...
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