Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 12

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
3
Content available remote The elements of modelling leg and monofin movements using a neural network
100%
|
|
tom Vol. 8, nr 1
55-63
EN
The aim of the study was to verify the diagnostic value of modelling the monofin swimming technique by means of artificial neural networks in order to optimize the technique of legs and monofin movements. The practical aspect of the modelling of the monofin swimming technique is apparent, since the interpretation of the propulsion as such is much less complicated than it is in the case of traditional swimming. Assuming that the technical level of the swimmers participating in the study is high (elimination of the redundant degree of freedom in the chain of swimmer’s body–monofin) the analysis was limited to the calf, foot and monofin movements. The model of the neural network allowed identifying the differences in the structure of the movements phases, pointing to extra margin that can be used to generate propulsion while making an upward movement and, simultaneously, paving the way to optimize the monofin swimming technique.
EN
The aim of the study is to identify the forces sagging the monofin during swimming. 14 high level swimmers first swam 50 m under water with maximal speed using a standard monofin. Next they swam anchored on the strain-gauge-equipped rope using the monofin famished with the gauges (in the middle and at the tail of its surface). The comparison of forces produced in both trials (using the dynamic statistics methods) demonstrated that the forces sagging the monofin in reaction to water resistance could be interpreted as the only source of swimmer's propulsion.
PL
W artykule scharakteryzowano pojęcie komunikacji dydaktycznej oraz zweryfikowano przebieg procesu nauczania wybranych dyscyplin rekreacji wodnej, tj.: pływania (na poziomie techniki standardowej), manewrowania żaglówką w obrębie manewrów prostych oraz podstaw nurkowania. Jednocześnie dokonano przeglądu badań zarówno w obrębie eksperymentów prowadzonych w zakresie metod nauczania tych dyscyplin pod kątem skuteczności nauczania, jak i bezpieczeństwa i zdrowia uczestników oraz sposobów porozumiewania się w wodzie, na wodzie i pod wodą. Komunikacja dydaktyczna pomiędzy nauczycielem a uczniem w odmiennym środowisku ze względu na jego specyfikę jest utrudniona. Dodatkowo nauczanie umiejętności na wodzie, w wodzie czy pod wodą wymaga zachowania i przestrzegania restrykcyjnych zasad bezpieczeństwa. Brak gotowości ucznia do działania w odmiennym środowisku wodnym u podłoża, którego leżą lęk lub strach, może zakłócać lub nawet uniemożliwiać komunikację dydaktyczną. W konsekwencji spada skuteczność nauczania. Celem pracy jest wskazanie nowatorskich form przekazu informacji dydaktycznej, które umożliwią trwałą zmianę zachowania ucznia szczególnie podczas działania w sytuacji trudnej – na wodzie, w wodzie i pod wodą. Istnieją przesłanki by sądzić, że natychmiastowa werbalna informacja oraz uwypuklenie w niej funkcji metajęzykowej podniesie jakość i efektywność procesu nauczania czynności ruchowych w odmiennym środowisku wodnym.
EN
This paper describes the concept of didactic communication and verifies the course of teaching selected disciplines of water based recreation, i.e. swimming (at the standard technique level), handling a sailing boat whilst undertaking simple manoeuvres, and the basics of diving. At the same time, research in the area of experiments conducted in the field of teaching methods of these disciplines was reviewed in terms of teaching effectiveness, as well as the health and safety of the participants, and ways of communicating while in, on and under the water. Communication between an instructor and a student in any environment which is different from the norm, is difficult owing to its specificity. Additionally, teaching skills on, in or under water requires strict observance of safety rules. Lack of student's readiness to act in a different water environment, be that based on anxiety or fear, may interfere with or, even prevent didactic communication. Consequently, the effectiveness of teaching decreases. The aim of this work is to search for innovative forms of information transfer that will enable a permanent change in the student's behaviour, especially when acting in a difficult environment – on the water, in the water and under the water. There are premises to believe that immediate verbal instruction and emphasising the metalinguistic function in it should improve the quality and effectiveness of the process of teaching activities in various water based environments.
PL
Bóbr europejski (Castor fiber L.) jest gatunkiem inżynierskim przyczyniającym się do wzrostu bioróżnorodności środowiska i poprawy bilansu wodnego zasiedlanych przez siebie terenów. Obok tych pozytywnych aspektów, gatunek ten oddziałuje również negatywnie na gospodarkę człowieka powodując konkretne policzalne straty gospodarcze. Większość szkód na badanym obszarze powstała w miejscach pierwotnej reintrodukcji bobrów, na rzece Piątkówka w gminie Błażowa. Charakter szkód wynikał ze zbyt bliskiego sąsiedztwa użytkowanych gruntów i stanowisk bytowania bobrów. W celu minimalizacji szkód powodowanych przez te zwierzęta, niektórzy rolnicy stosowali zabiegi ograniczające ponoszone straty oraz ubiegali się o rekompensaty za wyrządzone szkody.
EN
The European beaver (Castor fiber L.) is an engineering species which contributes to the growth of environmental biodiversity and improvement of water balance in the areas of its habitation. Besides those positive aspects, the species has negative impact on human activity as it causes specific, calculable economic losses. The study has showed that majority of damages on the investigated area occurred in the locations of the original reintroduction of beavers on the river Piątkówka in the Błażowa commune. The character of the damages resulted from the fact that beaver lodges were too close to agricultural lands. In order to minimize the damage caused by these animals some farmers used measures aimed at reducing the losses, and applied for financial compensation for the losses.
PL
Rękawice antywibracyjne są powszechnie stosowanym środkiem ochrony indywidualnej przed drganiami działającymi na pracownika przez kończyny górne. W normie EN ISO 10819:1996 (PN-EN ISO 10819:2000) sprecyzowano kryteria oceny ich właściwości antywibracyjnych, podano także metodę badań laboratoryjnych i wymagania dotyczące stanowiska badawczego. W 2013 r. do normy wprowadzono wiele zmian, w wyniku których stosowana wcześniej metoda badań uległa dezaktualizacji. Nowe wymagania dotyczą głównie rozszerzonego zakresu częstotliwości drgań, w którym przeprowadzane są pomiary, zwiększonej liczby sygnałów drgań/torów pomiarowych, sygnału testowego oraz sekwencji i liczby pomiarów. W artykule przedstawiono zmiany w metodyce badań rękawic antywibracyjnych wynikające z wymagań wprowadzonych w normie EN ISO 10819:2013.
EN
Anti-vibration gloves are the most commonly used means of personal protection against hand-arm vibration. The EN ISO 10819:1996 standard (PN-EN ISO 10819:2000) specifies the criteria for assessing their anti-vibration properties, also provides the laboratory test method and test bench requirements. In 2013 many changes were introduced to the standard, as a result of which the previously applied test method has become obsolete. The new requirements relate mainly to the extended vibration frequency range in which the measurements are carried out, the increased number of vibration/measurement signals, the test signal and the sequence and number of measurements. This article presents changes in the test methodology of anti-vibration gloves resulting from the requirements introduced in EN ISO 10819:2013.
EN
This study aims to find a relationship between the amplitude and duration of verbal information, and a conscious reaction to the kinaesthetic learner.Research participants in this study consisted of 40 children from elementary school No. 1 in Swidnica (Poland). The group consisted of 16 boys and 24 girls. The respondents' age ranged from 9 to 10 years. Children regularly attended swimming classes 3 times a week for 45 minutes. The method used for the research was the laboratory experiment method, where the aim was to assess the level of differentiation of kinaesthetic sensations in the aquatic environment. Study participants had to perform 10 repetitions of force differentiation of their upper limb adduction movements, under the influence of water resistance felt on the surface of the palm of their hands. The task was to move from the slightest perceptible drag force of water (sensory threshold), through intermediate values to the maximum strength.The results confirmed the hypothesis that the intentional modulation of verbal information affects the level of conscious differentiation force in the aquatic environment. The magnitude of the force registered during the measurements significantly correlated with the intensity of the amplitude of individual words and their duration.The participants' conscious reactions were therefore a response to the teacher's intentional and planned actions. This issue is worth addressing in more detail in subsequent studies. Verbal information should be supplemented with suitably chosen content and then evaluated in terms of its effectiveness relating to the teaching process.
PL
Celem badań było określenie wpływu składu różnych mieszanin oddechowych na wydolność wysiłkową szczurów podczas pływania w warunkach hiperbarii. Badano ją na podstawie wyników testu pływania do wyczerpania w komorze ciśnieniowej. Podczas badań używano powietrza atmosferycznego, mieszaniny azotu i tlenu (N2/02) w stosunku 89,5/10 oraz 92/7,5. a także mieszaniny argonu i tlenu w stosunku 79,5/20 (Ar/02). Próby badawcze odbywały się w zakresie ciśnień od 0-4 atm. Wyniki sugerują, że wydolność wysiłkowa badanych zwierząt spadała wraz ze wzrostem ciśnienia, niezależnie od stosowanej mieszaniny oddechowej. Z uwagi na fakt, że obciążenie szczurów wysiłkiem w warunkach hiperbarii potęguje niekorzystny wpływ składników mieszanin oddechowych na ich wydolność, celowa wydaje się kontynuacja badań nad reakcjami fizjologicznymi na czynnik oddechowy w postaci mieszanin oddechowych o różnym składzie w ustroju człowieka poddanego obciążeniu wysiłkiem pod wodą.
EN
The purpose of the study was to determine the effect of composition of various breathing mixes on physical capacity of rats swimming in hyperbaric conditions. The said effect was determined on the basis of results of a swim test performed in a pressure chamber. The study was performed with the use of atmospheric air, a mixture of nitrogen and oxygen (N2/02) at a ratio of 89.5/10 and 92/7.5, as well as a mixture of argon and oxygen at a ratio of 79.5/20 (Ar/02). The tests were conducted at a pressure range between 0-4 atm. The results suggest that the physical capacity of the tested animals decreased along with pressure increase regardless of the breathing mix used. Due to the fact that the burdening of rats with physical effort in hyperbaric conditions intensifies the adverse effects of components of breathing mixes on their performance, it seems appropriate to continue the study of physiological responses to breathing mixtures of various compositions in human body subjected to physical effort while under water.
EN
Early identification of anthropological potential in swimmers is considered important to the recruitment and selection of children and adolescents to perform extensive and strenuous training. The aim of the research was a comparative analysis of the anthropometric parameters and indicators of adult, elite swimmers with people who had never trained for swimming. It was assumed that the specific characteristics of the swimmers’ somatic composition referred to the laws of swimming biomechanics. Methods: Anthropometric measurements were taken in a group of elite male swimmers (N = 28), aged 17–24. The same set of measurements was taken in a homogeneous control group of students of physical education. An anthropometric profile significantly differentiating swimmers from the control group was constructed. Next, a linear forward stepwise discriminant analysis was conducted to investigate which indices can be used to distinguish the two groups. Results: It seems significant that a specific somatic composition trait of swimmers in the form of a relatively long shank was observed, which had not been observed in earlier studies. Additionally, indices of relatively slim hand dimension, and indices describing a “reversed triangle” shape of trunk, were the most powerful discrimination variables between the two examined groups. Conclusion: The results obtained cannot be generalised to the entire population of swimmers, however referring them to the laws of biomechanics of swimming allows for the continuation of research into identifying the prognostic traits desirable for success among young swimmers.
EN
The aim of this study was to analyse changes taking place within selected kinematic parameters of the swimming start, after completing a six-week plyometric training, assuming that the take-off power training improve its effectiveness. Methods: The experiment included nine male swimmers. In the pre-test swimmers performed three starts focusing on the best performance. Next, a plyometrics training programme, adapted from sprint running was introduced aimed at increasing explosive power of the lower extremities; the programme entailed 75 minute sessions conducted twice a week. Afterwards, a post-test was performed, analogous to the pre-test. Spatio-temporal structure data of the swimming start were gathered from video recordings of the swimmer both above and under water. Results: Impulses triggered by the plyometric training contributed to a shorter start time (the main measure of start effectiveness) and glide time as well as increasing average take-off, flight and glide velocities including take-off, entry and glide instantaneous velocities; the glide angle decreased. Conclusions: The changes in selected parameters of the swimming start and its confirmed diagnostic values, showed the areas to be susceptible to plyometric training and suggested, that applied plyometric training programme aimed at increasing take-off power enhances the effectiveness of the swimming start.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.