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1
Content available Assessment of Ground Ozone Level under the Physiological Strain Conditions
Sobolewski R. K., Kalbarczyk R.
Journal of Ecological Engineering
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2018
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Vol. 19, nr 4
207--216
EN
Urban areas are characterised by the impact of negative environmental factors, such as: stress connected with extreme bio-thermal conditions or the presence of high concentrations of air pollutants. This study aims to evaluate the relationship between the hours of O3 concentrations and the levels of physiological strain (PhS) in Legnica, during the period from December 2013 to November 2014. The hourly concentrations of O3, NO2 and meteorological elements used in the study were obtained from the State Environmental Monitoring station in Legnica (Lower Silesia). The evaluation of the bio-thermal conditions was carried out by means of the physiological strain indicator (PhS). The basic statistics were subject to analysis, the frequency of hourly pollution concentrations and the thermal strain were evaluated, as was the Pearson correlation coefficient and multiple regression between O3 and PhS. A detailed analysis was carried out for the summer months (June-August). The most adverse conditions in terms of pollution with tropospheric ozone and heat strain were noted in July. The strongest relations between O3 and PhS were observed in June. In winter months (December-February) no significant dependencies were noted between the tested variables. These tests will help to contribute to increasing the current knowledge on evaluating the thermal comfort of urbanised areas and the accompanying aero-sanitary conditions.
2
Content available Behaviour of cement concrete at high temperature
Hager I.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2013
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Vol. 61, nr 1
145-154
EN
The paper presents the impact of high temperature on cement concrete. The presented data have been selected both from the author’s most recent research and the published literature in order to provide a brief outline of the subject. The effect of a high temperature on concrete covers changes taking place in cement paste, aggregates, as well as the interaction of these two constituents, that result in changes of mechanical and physical characteristics of concrete. This paper presents the effects of a high temperature on selected physical properties of concrete, including colour change, thermal strain, thermal strains under load, and transient thermal strains. In addition, changes to mechanical properties are discussed: stress-strain relationship, compressive strength, and modulus of elasticity. Moreover, the phenomenon of explosive spalling and the main factors that affect its extent are analysed in light of the most recent research.
3
Symulacja naprężeń cieplnych występujących podczas chłodzenia retort pomiarowych
Ryciak S., Kiełczewski R., Grotkowski Ł.
Elektronika : konstrukcje, technologie, zastosowania
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2011
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Vol. 52, nr 7
69-72
PL
W artykule opisano proces symulacji naprężeń cieplnych i odkształceń, którym ulega retorta pomiarowa w jednym z urządzeń konstruowanych przez Instytut Tele- i Radiotechniczny. Przedstawiono porównanie wyników otrzymanych za pomocą różnych metod symulacyjnych oraz ich zastosowanie i wpływ na konstrukcję urządzenia.
EN
The document describes simulation of thermal strains and deformation which occures in process reactor. Presented comparison shows results obtained with different simulation methods and it's application in construction of actual device.
4
Content available Thermal Strain in Fire Fighters While Wearing Task-Fitted Versus EN 469:2005 Protective Clothing During a Prolonged Rescue Drill
Ilmarinen R., Makinen H., Lindholm H., Punakallio A., Kervinen H.
International Journal of Occupational Safety and Ergonomics
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2008
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Vol. 14, No. 1
7--18
EN
Fire fighters are normally overprotected during their working hours because of the tendency to keep the personal protection level sufficiently high in case of the worst possible scenarios. This study investigated the effects of task-fitted protective clothing on thermal strain in fire fighters as compared to EN 469:2005 protective clothing during a prolonged (2 1/2 hrs) job-related rescue drill under neutral and hot climates. The subjects were 23 healthy, physically fit professional male fire fighters aged 26–44 years. Measurements included cardiovascular and thermal responses and subjective assessments. Wearing task-fitted clothing during rescue tasks in a neutral climate considerably reduced total thermal and cardiovascular strain in prolonged rescue work. The fire fighters also perceived physical work as significantly harder on average, and reported more intense subjective discomfort while wearing EN 469:2005 as compared to task-fitted clothing.
5
Content available Effectiveness of a Light-Weight Ice-Vest for Body Cooling While Wearing Fire Fighter’s Protective Clothing in the Heat
Smolander J., Kuklane K., Gavhed D., Nilsson H., Holmer I.
International Journal of Occupational Safety and Ergonomics
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2004
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Vol. 10, No. 2
111--117
EN
The aim of the study was to examine the effects of wearing an ice-vest (ca 1 kg) on physiological and subjective responses in fire fighters. The experiments were carried out on a treadmill in a hot-dry environment. The physical cooling effect of the ice-vest was measured with a thermal manikin. The ice-vest effectively reduced skin temperatures under the vest. On average, heart rate was 10 beats/min lower, the amount of sweating was reduced by 13%, and subjective sensations of effort and warmth were lower during work with the ice-vest compared to work without it. Thermal manikin tests indicated that the useful energy available from the vest for body cooling was rather high (58%). In conclusion, the ice-vest reduces physiological and subjective strain responses during heavy work in the heat, and may promote efficient work time by 10%.
6
Content available remote Doslihdzhennja temperaturno-zsihdnikh deformacihjj ta monolihtnostih sistemi "Beton - vognezakhisne pokrittja"
Shnal' T., Nazarevich B., Vlasov V.
Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska
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2000
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z. 32[180], cz.1
525-530
EN
In clause the results of researches temperature - shrinkage of deformations and solidity of system "concrete - fireproof a covering" are given, the recommendations for application bloating coating for protection of steel-concrete designs are given.
7
Content available Thirst and Work Capacity of Older People in a Hot Environment
Marszałek A.
International Journal of Occupational Safety and Ergonomics
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2000
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Zeszyt Specjalny
135--142
EN
In a hot environment, especially during exercise, the main role of thermoregulative mechanisms is to dissipate excessive heat from the body. The most effective way of heat dissipation is sweat production and its evaporation off skin surface. Intense sweating results in a considerable loss of water and electrolytes. There are some results that indicate lower thirst of older men than young ones in response to a hot environment and osmotic stimuli. Our studies conducted in men of different ages exposed to a hot environment indicated that there were no significant differences in rectal temperature (Tre) or heat storage (S) among groups at rest. Lower Tre and lower S in older men with higher physical capacity for their age than in young ones with average physical capacity was shown. However, in all the experiments significantly lower thirst in older men than in the young was indicated. Special attention should be paid to fluid replacement among workers in a hot environment because of lower thirst and lower hydration of older men. These individuals may be exposed to dehydration risk during prolonged exercise, despite the possibility to tolerate heat strain as well as young ones. Further studies are necessary because of some diversity in the meaning of the results.
8
Termo-sprężysto-plastyczne odkształcenie pręta oddziałującego ze sprężystym podłożem
Wesołowski Z.
Przegląd Mechaniczny
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1999
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23-24
28-33
EN
An analysis of a thermal-elastic-plastic strain of a model rod thermally insulated lengthwise and laser-heated at one end. This analysis is supplemented by numerical calculations for a concrete material of the rot. The calculation results concern temperature and stress distribution in the modell rod.
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