排序方式: 共有18条查询结果,搜索用时 31 毫秒
11.
Kalev Kuklane Chuansi Gao Faming Wang Ingvar Holmér 《International journal of occupational safety and ergonomics》2013,19(2):171-179
AbstractStandard No. EN 15831:2004 provides 2 methods of calculating insulation: parallel and serial. The parallel method is similar to the global one defined in Standard No. ISO 9920:2007. Standards No. EN 342:2004, EN 14058:2004 and EN 13537:2002 refer to the methods defined in Standard No. EN ISO 15831:2004 for testing cold protective clothing or equipment. However, it is necessary to consider several issues, e.g., referring to measuring human subjects, when using the serial method. With one zone, there is no serial-parallel issue as the results are the same, while more zones increase the difference in insulation value between the methods. If insulation is evenly distributed, differences between the serial and parallel method are relatively small and proportional. However, with more insulation layers overlapping in heavy cold protective ensembles, the serial method produces higher insulation values than the parallel one and human studies. Therefore, the parallel method is recommended for standard testing. 相似文献
12.
Miguel Villoslada Robert G. H. Bunce Kalev Sepp Rob H. G. Jongman Marc J. Metzger Tiiu Kull Janar Raet Valdo Kuusemets Ain Kull Aivar Leito 《Regional Environmental Change》2017,17(2):335-349
Environmental stratifications provide the framework for efficient surveillance and monitoring of biodiversity and ecological resources, as well as modelling exercises. An obstacle for agricultural landscape monitoring in Estonia has been the lack of a framework for the objective selection of monitoring sites. This paper describes the construction and testing of the Environmental Stratification of Estonia (ESE). Principal components analysis was used to select the variables that capture the most amount of variation. Seven climate variables and topography were selected and subsequently subjected to the ISODATA clustering routine in order to produce relatively homogeneous environmental strata. The ESE contains eight strata, which have been described in terms of soil, land cover and climatic parameters. In order to assess the reliability of the stratification procedure for the selection of monitoring sites, the ESE was compared with the previous map of Landscape Regions of Estonia and correlated with five environmental data sets. All correlations were significant. The stratification has therefore already been used to extend the current series of samples in agricultural landscapes into a more statistically robust series of monitoring sites. The potential for applying climate change scenarios to assess the shifts in the strata and associated ecological impacts is also examined. 相似文献
13.
Hannu Anttonen Juhani Niskanen Harriet Meinander Volkmar Bartels Kalev Kuklane Randi E Reinertsen Sabine Varieras Krzysztof So?tyński 《International journal of occupational safety and ergonomics》2004,10(3):291-300
According to the European prestandard ENV 342:1998, the thermal insulation of cold-protective clothing is measured with a thermal manikin. Systematic studies on the reproducibility of the values, measured with different types of clothing on the commonly used standing and walking manikins, have not been reported in the literature. Over 300 measurements were done in 8 different European laboratories. The reproducibility of the thermal insulation test results was good. The coefficient of variation was lower than 8%. The measured clothing should fit the manikin precisely, because poorly fitting clothing gave an error in the results. The correlation between parallel and serial insulation values was excellent and parallel values were about 20% lower than serial ones. The influence of ambient conditions was critical only in the case of air velocity. The reproducibility of thermal insulation test results in a single laboratory was good, and the variation was lower than 3%. 相似文献
14.
Ingvar Holmér Kalev Kuklane Chuansi Gao 《International journal of occupational safety and ergonomics》2006,12(3):297-305
Five students of a rescue training school cycled at 50 W for 20 min at 20 degrees C before walking at 5 km/hr up to 30 min in a climatic chamber at 55 degrees C and 30% relative humidity. 4 different types of clothing ensembles differing in terms of thickness and thermal insulation value were tested on separate days. All subjects completed 28-30 min in light clothing, but quit after 20-27 min in 3 firefighter ensembles due to a rectal temperature of 39.0 degrees C or subjective fatigue. No difference in the evolution of mean skin or rectal temperature was seen for the 3 turnout ensembles. Sweat production amounted to about 1000 g in the turnout gears of which less than 20% evaporated. It was concluded that the small differences between the turnout gears in terms of design, thickness and insulation value had no effect on the resulting heat physiological strain for the given experimental conditions. 相似文献
15.
Kalev Kuklane Chuansi Gao Ingvar Holmér Lina Giedraitytė Peter Bröde Victor Candas 《International journal of occupational safety and ergonomics》2013,19(2):103-116
Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values.Tests were carried out on 8 subjects. The results showed the possibility of incorporating the effect of increases in metabolic rate values due to thick cold protective clothing into the IREQ model. Using the higher thermal insulation value from the serial method in the IREQ prediction, would lead to unacceptable cooling of the users. Thus, only the parallel insulation calculation method in EN 342:2004 should be used. The wind and motion correction equation (No. 2) gave realistic values for total resultant insulation; dynamic testing according to EN 342:2004 may be omitted. 相似文献
16.
17.
Calculation of clothing insulation by serial and parallel methods: effects on clothing choice by IREQ and thermal responses in the cold. 总被引:1,自引:0,他引:1
Kalev Kuklane Chuansi Gao Ingvar Holmér Lina Giedraityte Peter Br?de Victor Candas Emiel den Hartog Harriet Meinander Mark Richards George Havenith 《International journal of occupational safety and ergonomics》2007,13(2):103-116
Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values. Tests were carried out on 8 subjects. The results showed the possibility of incorporating the effect of increases in metabolic rate values due to thick cold protective clothing into the IREQ model. Using the higher thermal insulation value from the serial method in the IREQ prediction, would lead to unacceptable cooling of the users. Thus, only the parallel insulation calculation method in EN 342:2004 should be used. The wind and motion correction equation (No. 2) gave realistic values for total resultant insulation; dynamic testing according to EN 342:2004 may be omitted. 相似文献
18.
Mengmeng Zhao Kalev Kuklane Karin Lundgren Chuansi Gao Faming Wang 《International journal of occupational safety and ergonomics》2013,19(4):457-463
The aim of the study was to identify whether a ventilation cooling shirt was effective in reducing heat strain in a hot climate. Eight female volunteers were exposed to heat (38?°C, 45% relative humidity) for 2?h with simulated office work. In the first hour they were in normal summer clothes (total thermal insulation 0.8?clo); in the second hour a ventilation cooling shirt was worn on top. After the shirt was introduced for 1?h, the skin temperatures at the scapula and the chest were significantly reduced (p?<?0.05). The mean skin and core temperatures were not reduced. The subjects felt cooler and more comfortable by wearing the shirt, but the cooling effect was most conspicuous only during the initial 10?min. The cooling efficiency of the ventilation shirt was not very effective under the low physical activity in this hot climate. 相似文献