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排序方式: 共有172条查询结果,搜索用时 109 毫秒
1.
Tamar Ben-Bassat David Shinar Raquel Almqvist Jeff K. Caird Robert E. Dewar Esko Lehtonen 《Ergonomics》2019,62(6):734-747
Traffic sign comprehension is significantly affected by their compliance with ergonomics design principles. Despite the UN Convention, designs vary among countries. The goal of this study was to establish theoretical and methodological bases for evaluating the design of conventional and alternative signs. Thirty-one conventional signs and 1–3 alternatives for each conventional sign were evaluated for their compliance with three ergonomics guidelines for sign design: physical and conceptual compatibility, familiarity and standardisation. Twenty-seven human factors and ergonomics experts from 10 countries evaluated the signs relative to their compliance with the guidelines. Analysis of variance across alternatives revealed that for 19 of the 31 signs, an alternative design received a significantly higher rating in its ergonomics design than the conventional sign with the same meaning. We also found a very high correlation between the experts’ ratings and comprehension from previous studies. In conclusion, many countries use signs for which better alternative designs exist, and therefore UN Convention signs should be re-examined, and ergonomics experts evaluation can serve as a good surrogate for road users’ comprehension surveys.
Practitioner summary: This study presents theoretical and methodological bases for evaluating the design of UN Conventional and alternative traffic signs. Human factors and ergonomics experts evaluated 31 conventional and 68 alternative road signs, based on ergonomics principles for sign design. Results indicated the need to re-examine poorly designed UN Convention signs. 相似文献
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Serban N. Stamatin Maryam Borghei Shuang Ma Andersen Sune Veltze Virginia Ruiz Esko Kauppinen Eivind M. Skou 《International Journal of Hydrogen Energy》2014
Commercially available graphitized carbon nanofibers and multi-walled carbon nanotubes, two carbon materials with very different structure, have been functionalized in a nitric–sulfuric acid mixture. Further on, the materials have been platinized by a microwave assisted polyol method. The relative degree of graphitization has been estimated by means of Raman spectroscopy and X-ray diffraction while the relative concentration of oxygen containing groups has been estimated by X-ray photoelectron spectroscopy, which resulted in a graphitic character trend: Pt/GNF > Pt/F-GNF ? Pt/MWCNT > Pt/F-MWCNT. Transmission electron microscopy showed that the Pt particle size is around 3 nm for all samples, which was similar to the crystallite size obtained by X-ray diffraction. The activity towards electrochemical reduction of oxygen has been quantified using the thin-film rotating disk electrode, which has shown that all the samples have a better activity than the commercially available electrocatalysts. The trend obtained for the graphitic character maintained for the electrochemical activity, while the reverse trend has been obtained for the accelerated ageing test. Long-term potential cycling has demonstrated that the functionalization improves the stability for multi-walled carbon nanotubes, at the cost of decreased activity. 相似文献
4.
Sari Linnea Merilampi Toni Bj?rninen Leena Ukkonen Pekka Ruuskanen Lauri Syd?nheimo 《The International Journal of Advanced Manufacturing Technology》2011,53(5-8):577-591
The possibility of pad printing in RFID tag antenna manufacturing is investigated. Passive UHF RFID tags were printed on flat and on convex surfaces with two different polymer thick-film silver inks. The effect of the ink and substrate material properties on tag antenna performance was examined. The goal was to provide information which is needed in adapting the pad-printing technique in RFID tag manufacture. The results show that pad printing is suitable for tag manufacturing on flat and on convex surfaces. The curvature of the substrate did not significantly affect the tag performance. It was more important to take into consideration other substrate properties, ink characteristics, morphology, and printing parameters. The best practice is to take these matters into consideration in the initial tag design process to ensure proper tag performance at the desired frequency. 相似文献
5.
Ying Tian Marina Y. Timmermans Matti Partanen Albert G. Nasibulin Hua Jiang Zhen Zhu Esko I. Kauppinen 《Carbon》2011,(14):4636-4643
On the basis of combined study of the transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and ultraviolet–visible–near infrared absorption spectroscopy, the properties of the single-walled carbon nanotubes (SWCNTs), synthesized by aerosol (floating catalyst) chemical vapor deposition method by ferrocene vapor decomposition in the presence of carbon monoxide, are studied in details. The results show that increasing the temperature gives rise to the formation of high quality and large diameter SWCNTs. By monitoring the water-cooled probe position, both the bundle length and the diameter of the SWCNTs are effectively tuned due to the variation of the residence time and temperature profile in the reactor. An introduction of a small amount of CO2 suppresses the growth of small diameter nanotubes and enlarges the mean diameter of SWCNT samples. The mean diameter of SWCNTs could be easily altered in a broad range from 1.1 to 1.9 nm during growth, which is essential for the SWCNT applications in optical and electronic devices. 相似文献
6.
Previous research on driver drowsiness detection has focused on developing in-car systems that continuously monitor the driver while driving and warn him/her when drowsiness compromises safety. In occupational settings a simple test of postural control has showed sensitivity to work shift induced fatigue in drivers. Whether the test is feasible for surveillance purposes in roadside settings is unknown. The present research sought to evaluate the feasibility of using a force platform test of postural control as a breathalyzer-like drowsiness-test at the roadside. 相似文献
7.
The fire risk assessment model CRISP2 was applied to a 4‐storey apartment building. The case building was an actual 4‐storey timber‐framed building. Partly predetermined design alternatives were used in sequential simulations. CRISP2 cannot take into account the frame‐material of the building in a satisfactory way, because the wall thickness, structural fire resistance or lining materials in the fire room cannot be modelled. It was found that adding smoke alarms almost halved the risk level. The risk levels 1–2×10?5 obtained are not far from comparable levels of fire death statistics from Finland, the United Kingdom, Sweden and Norway. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
8.
Albert G. Nasibulin Olivier Richard Esko I. Kauppinen David P. Brown Jorma K. Jokiniemi Igor S. Altman 《Aerosol science and technology》2013,47(8):899-911
Crystalline nanometer-sized Cu 2 O and CuO particle formation was studied by vapor thermal decomposition of copper (II) acetylacetonate in a vertical laminar flow reactor at ambient pressure. Experiments were carried out at 3 furnace temperature profiles (maximum values of t furn = 432, 596, 705°C) and with 2 carrier gases (oxygen/nitrogen with mixture ratios of 0.5/99.5 and 10.0/90.0). The results of computational fluid dynamics simulations are presented. The introduction of oxygen into the system was found to increase the decomposition rate and removed impurities from particles. The size of produced primary particles varied from 10 to 200 nm. Particle crystallinity was found to depend on both the oxygen concentration and the furnace temperature. A model taking into account the detailed chemical reaction mechanisms during the particle formation is proposed. The model allows one to build a dynamic phase diagram of the condensed products formed during the decomposition and is in good agreement with the experimental results. 相似文献
9.
In Finnish groundwater, the main substances that require treatment are iron and manganese. In addition to this, groundwaters are soft and acidic. Iron removal is usually relatively effective by oxidizing dissolved iron into an insoluble form, either by aeration or chemical oxidization and removing the formed precipitate by sand filtration. Sometimes, if the untreated water contains high amounts of organic matter, problems may arise for iron removal. In Finland, it is quite common that groundwater contains high levels of both iron and natural organic matter, mainly as humic substances. The groundwater of the Kukkala intake plant in Liminka has been found to be problematic, due to its high level of natural organic matter. This research studied the removal of iron from this water by means of oxidation with ozone and filtration. While the oxidation of iron by ozone was rapid, the precipitate particles formed were small, and thus could not be removed by sand and anthracite filtration, and the iron residue in the treated water was more than 2 mgL?1. And while the filtration was able to remove iron well without the feed of ozone, the iron residue in the treated water was only 0.30 mgL?1. In this case, iron was led to the filter in a bivalent dissolved form. So, the result of iron removal was the best when the sand/anthracite filter functioned largely as an adsorption filter. 相似文献
10.
Manganese is a commonly found substance in groundwater in Finland. As a powerful oxidant, ozone can be used for the oxidizing of manganese even without raising the pH. The SFS (Finnish Standards Association) standard has set the accepted limit for soluble manganese to 0.45 μm. However, some research papers have used the limit of 30 kD (kilodalton) for soluble manganese. This research concentrates on the size fractions of manganese in four samples of untreated groundwater and in four samples of ozonized groundwater when treated with 0.45 μm, 0.20 μm, 100 kD, 30 kD, and 10 kD filters. In all tests, nearly all manganese contained in raw water penetrated all filters. There were slight variations in the flocculation of manganese in ozonized groundwater; nevertheless, hardly any reduction in manganese levels took place beyond 100 kD. After ozonation, there were two water samples which surpassed the manganese limit of 50 μgl?1 set for domestic water when the filtration was 0.20 μm and another two samples when the filtration was 100 kD. 相似文献