PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 13

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
1
Content available The influence of vibrations generated by handheld household appliances on temperature changes of user hands
Wojsznis M., Mazurek I., Różański L., Barczewski R.
Vibrations in Physical Systems
|
2018
|
Vol. 29
art. no. 2018024
EN
The paper presents an analysis of influence of vibrations generated by small hand-held household appliances on temperature changes of hands. To visualize thermal changes of operators’ hands a thermographic camera was used. During the tests values of acceleration of device handle vibrations at points of contact with operators’ hands were recorded simultaneously. It has been observed that even during short periods of work the hand temperature changes significantly. The biggest recorded change was equal to 3°C. The tests have shown that the influence of vibrations is in this case sensed more strongly particularly by fingers and a wrist. The analysis of results has shown purposefulness of pointing out synergistic influence of vibrations and thermal changes caused by commonly available appliances on a human body.
2
Content available Evaluation of a simple method of identification of dynamic parameters of a single-degree-of-freedom system
Tabaszewski M., Wojsznis M.
Vibrations in Physical Systems
|
2017
|
Vol. 28
art. no. 2017005
EN
The paper presents a simple method of identification of dynamic parameters of single-degree-of-freedom systems based on an impulse test. Numerical simulations consisting in generating a model impulse excitation and the response of a model system with specified dynamic parameters to this excitation have been carried out to present the applicability range of the method. The influence on parameter estimation errors at various set values of these parameters and procedure parameters has been investigated.
3
Content available Analysis of vibration transmission in an air-operated demolition hammer
Tabaszewski M., Wojsznis M.
Vibrations in Physical Systems
|
2016
|
Vol. 27
385--390
EN
The paper presents an analysis of vibrations of a ram, body and handle of a heavy, air-operated demolition hammer. The research was conducted in order to determine the character of dynamic inputs and resulting vibrations at the tool handle which were necessary to build a structural model of local influences on an operator taking the hammer design into account. The experiment was carried out on a test stand without participation of an operator, which guaranteed repeatability of measurements and elimination of ontogenetic characteristics. The displacements of selected structural elements of the tool were recorded by means of a camera and the accelerations at the handle were recorded by means of a standard measuring apparatus. The recorded signals were subjected to the spectral analysis and the short-time Fourier transform (STFT) using dedicated software in MATLAB environment.
4
Content available Infrasound and low frequency noise of a wind turbine
Wojsznis M., Szulczyk J.
Vibrations in Physical Systems
|
2014
|
Vol. 26
327--334
EN
The paper presents noise evaluation for a 2 MW wind turbine. The obtained results have been analyzed with regard to infrasound and low frequency noise generated during work of the wind turbine. The evaluation was based on standards and decrees binding in Poland. The paper presents also current literature data on the influence of the infrasound and low frequency noise on a human being. It has been concluded, that the permissible levels of infrasound for the investigated wind turbine were not exceeded.
5
Content available remote Vibration research on a demolition hammer using a high-speed camera
Wojsznis M., Tabaszewski M., Dobry M. W.
Vibrations in Physical Systems
|
2012
|
Vol. 25
453--458
EN
The paper presents methodology of measurements and results of vibration research on a demolition hammer weighing 15.5 kg. The measurements of vibrations for the chosen measuring points have been carried out using a Photron FastCam 1024 PCI high-speed camera on a stand prepared for testing hand-held tools. To ensure signal stability and to reduce the influence of an operator the research was carried out with the hammer mounted in a special fixture enabling holding a tool with symmetric layout of handles. The measurement results are to be used for verification of a model assumed for a human being – tool system.
6
Content available remote Analysis of local vibrations in a vehicle
Wojsznis M.
Vibrations in Physical Systems
|
2012
|
Vol. 25
447--452
EN
The paper presents a problem of local vibrations in a vehicle as one of physical factors occurring at the driver’s place. Influence of tires used in a car on local vibrations generated in a steering mechanism has been considered here. The analysis of local vibration hazards was carried out based on experimental results published in [1]. The measurement results obtained for five types of tires differing, among other things, from one another in tread depth, degree of wear and use were analyzed. The analysis has revealed significant influence of tires on the level of local vibrations transmitted through the steering mechanism into driver’s hands.
7
Content available remote Spatial model of a human being - demolition hammer system
Wojsznis M., Dobry M. W.
Vibrations in Physical Systems
|
2008
|
Vol. 23
427--434
EN
The paper presents a model of a Human being – Demolition Hammer system (C-MW) taking into account the motion of the system in three directions x, y, z.. The following models were used to create the model: Meltzer model from 1980, the model from the ISO 10068 standard and authors’ own Human Being – Big Power Driven Hand Tool (C-DZNR) model developed in 2000. Dynamic parameters were taken from the ISO 10068 standard for each direction of motion. Identification of tool parameters still needs accurate verification.
8
Content available remote Energy model of a spatial human being – demolition hammer system with WoSSO vibroisolation
Dobry M. W., Wojsznis M.
Vibrations in Physical Systems
|
2008
|
Vol. 23
103--108
EN
The paper concerns the problem of energy modeling of a spatial Human Being – Demolition Hammer system with WoSSO vibroisolation (C-MWzWoSSO). For this purpose, first, new spatial physical and mathematical models of the system were developed with the use of the data presented in the ISO 10068 standard. Then, a model of energy flow in a dynamic structure of the investigated system was built.
9
Content available remote Energy analysis of a model of a human being-tool system for different elbow joint inclination angles
Wojsznis M.
Vibrations in Physical Systems
|
2008
|
Vol. 23
423--428
EN
The paper presents the influence of parameter change of a bio-mechanical Human Being – Machine model on energy quantities. The energy analysis concerned instantaneous power, average power and an energy dose directed into a human operator. The model used consisted of a biological part made up of a hand-arm system (both upper limbs) and a mechanical part made up of a tool (e.g. a demolition hammer). The analysis showed that asymmetric arrangement of upper limbs in the system causes an increase in all measured quantities.
10
Content available remote Analysis of energy flow in a Human Being – machine system with application of energy portraits of power
Wojsznis M., Dobry M. W.
Vibrations in Physical Systems
|
2006
|
Vol. 22
373--378
11
Content available remote The influence of positioning of hands on energy quantities – Meltzer model
Wojsznis M., Dobry M.
Vibrations in Physical Systems
|
2004
|
Vol. 21
419--422
12
Content available Oddziaływanie drgań miejscowych na organizm ludzki - ocena analizy dynamicznej i energetycznej
Dobry M. W., Wojsznis M.
Diagnostyka
|
2004
|
Vol. 30, T. 1
151--154
PL
W pracy zaprezentowano analizę dynamiczną i energetyczną systemu człowiek- zmechanizowane narzędzie ręczne. Przedstawione przebiegi mocy chwilowej sprężystości pozwoliły określić miejsca największej koncentracji przepływu energii w badanym systemie. Wyniki analizy energetycznej zgadzają się z danymi medycznymi zebranymi dla osób pozostających pod długotrwałym wpływem drgań mechanicznych generowanych przez pracujące narzędzia. Analiza dynamiczna przeprowadzana w dziedzinie amplitud przyspieszeń drgań, jako wielkości kryterialnej, wykazała rozbieżności tej oceny. Analiza energetyczna wykazała zatem zgodność oceny wpływu drgań na organizm człowieka ze skutkami szkodliwego oddziaływania drgań wykazanymi w raportach medycznych w postaci uszkodzeń stawów kończyn górnych.
EN
The paper presents dynamical and energy analyses of a human - power hand-held tool system. The presented characteristics of instantaneous power of elasticity allowed defining points with the highest concentration of energy flow in the investigated system. The results of energy analysis are coherent with medical data gathered from people who had been exposed to vibrations generated by working tools for a very long time. The dynamical analysis in the domain of vibration acceleration amplitudes showed divergence in the evaluation. Hence, the energy analysis showed consistence in the assessment of influence of vibrations on a human body with the effects of damaging influence of vibrations showed in medical reports as damage to upper limb joints.
13
Content available remote Analiza energetycznego oddziaływania dużego zmechanizowanego narzędzia udarowego na człowieka
Wojsznis M., Dobry M. W.
Czasopismo Techniczne. Mechanika
|
2004
|
R. 101, z. 5-M
379--387
PL
W niniejszej pracy przedstawiono energetyczną analizę wpływu drgań mechanicznych generowanych przez Duże Zmechanizowane Narzędzie Ręczne na człowieka-operatora. Wykorzystując Pierwszą Zasadę Przepływu Energii w Systemie Mechanicznym i Pierwszą Zasadę Dystrybucji Mocy w Systemie Mechanicznym sformułowanym przez Dobrego, zbudowano model układu Człowiek-Maszyna, zakładając niezależne rozpatrywanie rąk w tym systemie jako dwie drogi transmisji energii. Za pomocą programu symulacyjnego PEC-DZNR 2001 (ISO) otrzymano przebiegi w czasie: przemieszczeń, prędkości, przyspieszeń oraz mocy chwilowych w całym badanym systemie, jak i w poszczególnych punktów redukcji. Dysponując tymi sygnałami w rozpatrywanych punktach redukcji sporządzono widma gęstości mocy tych sygnałów. Otrzymane istotne amplitudy i ich częstotliwości w składzie widma porównano z częstościami rezonansowymi organów człowieka dostępnymi w literaturze, w celu zbadania wpływu drgań mechanicznych na organizm ludzki. Rezultaty badań wykazały, że ustalone energetycznie istotne amplitudy i ich częstotliwości drgań występują w zakresach częstotliwości rezonansowych części ciała ludzkiego i wywołują zjawisko ich rezonansu. Taki stan jest powodem wywołania zespołu choroby wibracyjnej u operatorów tych narzędzi.
EN
The paper presents energy analysis of the influence of mechanical vibrations generated by a big powered hand-held tool on a human-operator. Taking into account the First Principle of Energy Flow in a Mechanical System and the First Principle of Power Distribution in a Mechanical System formulated by Dobry, a model of a Human-Machine system was developed considering each hand independently as a separate path of energy transmission. With the help of simulation program PEC-DZNR 2001 (ISO) time functions of displacements, velocities, accelerations and instantaneous powers both in the whole investigated system and at the particular points of reduction were obtained. Basing on the signals for the considered points of reduction power density spectra were made. In order to check the influence of mechanical vibrations on a human body, the obtained significant amplitudes significant amplitudes and their frequencies were compared with resonance frequencies of parts of human body, which can be found in literature. The investigation results showed that the established energy significant vibration amplitudes and their frequencies appear near the resonance frequencies of the parts of a human body and cause their resonance. This causes Vibration induced White Finger disease among human operators.
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.