Suchergebnisse

Most government efficiency programmes focus on reducing energy losses in the distribution network and for some of them even provide metrics for these improvements. A large amount of these losses comes from distribution transformers and the manufacturers are encouraged to improve the efficiency of their designs. These improvements are often managed with the use of better materials and then increase of transformer costs. The need for accurate loss measurements is therefore increased if the manufacturers do not want to their efforts to be affected by the measurement uncertainties of a measurement system. Proving a small improvement in efficiency, even at high cost for the manufacturer, will be difficult if the measurement system cannot measure this improvement accurately. Accuracy of measurement systems and comparison of the accuracy are of the utmost importance and have been a topic of discussions among experts for years. The article will describe how a modern measurement system can be accurate, assess its accuracy for every measurement performed and confirm the stability of their accuracy over time. In this approach, not only is the measurement important, but also the complete chain, data management, reporting and accuracy assessment of the measurement have to be automatically computed for the end user.

Abstract
Skin hydration and the barrier properties of the stratum corneum have been reported to be influential factors in the potential for retention of solid and semi-solid substances on the skin surface. The measurement of these characteristics of the skin, however, remains relatively uncommon in exposure assessments performed by industrial or occupational hygienists, even when the focus of the assessment is exposure to the skin. This study provides measurements of skin hydration using multiple instruments and multiple relevant skin site locations for comparative analysis. Three different measurement metrics, trans-epidermal water loss (TEWL), hydration index (HI), and percent hydration, were measured for 25 healthy volunteers at two different body locations for comparison: the center of the volar forearm, as previously recommended for interindividual comparison of hydration and barrier property measurements, and also the palmar tip of the index finger. The purpose of the comparative measurements was to allow for comparison between other published baseline volar forearm measurements and the palmar skin, which has not often been quantitatively assessed and reported in the literature, but is a relevant skin surface for sampling of the hands. This comparison will allow for consideration of the potential influence of palmar wipe sampling protocols on TEWL or skin hydration, and for the evaluation of the influence of skin hydration and TEWL on measured dermal transfer values. Collectively, the skin hydration levels and barrier properties at these two different measurement locations were found to be statistically significantly different, and as a result it is suggested that they be measured and recorded separately. Both measurement types and locations are likely to be important for the purposes of establishing skin hydration and health. Volar forearm measurements can also be important for understanding the underlying condition and barrier function of the skin, and palmar index finger measurements are necessary to understand the influence of both TEWL and skin hydration on quantitative dermal loading and transfer of solids and semi-volatile materials.

Author's Accepted Version of a paper accepted for presentation in the 21st International Symposium on High Voltage Engineering (ISH2019), Budapest, Hungary, August 26-30, 2019. ; The work reported here has received support from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme.

This paper covers a number of pitfalls that could hinder the development of a common methodology for estimating flood damage. Such pitfalls include double counting, ignoring post‐disaster liabilities, ignoring non‐market losses (e.g. recreation, loss of leisure, damage to historic sites and cultural assets, etc.), ignoring the needs of the end user, and questions as to how indirect/systemic losses might be modeled. With one exception, much of what is discussed in the paper is based on off‐the‐shelf economics and will not prove to be contentious. Regional economists are likely to have different opinions as to how to best model indirect and systemic loss; it is this that will lead to a lively debate as to how to proceed. Assessments of economic fallout from the World Trade Center attack are used to illustrate some of the problems reported in this paper.

A calorimetric measuring system for measuring the ratio between AC and DC resistance, RAC/RDC, of high voltage power cable conductors has been designed and constructed. An uncertainty analysis predicts that the ratio RAC/RDC at 90°C of a 2500 mm2 cable of low loss design can be measured with an uncertainty of 1,0%. But the uncertainty of an actual measurement was larger due to unresolved sources of uncertainty. ; The work reported here has received support from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme.

This report presents measurements of sound attenuation due to a barrier placed between a source and four receiving positions in the anechoic chamber at IRC. The measurements were made on behalf of Public Works and Government Services Canada (PWGSC). This report is the fourth in a series. The first report presents measurements of sound propagation made in nine offices. The second report presents measurements of speech levels in the offices. Background and some design information for open offices can be found in the third report. The fifth report presents results of a study on the effect of speaker orientation and reflectivity of vertical surfaces in open 'team-style' offices in a simulated office in the laboratory. The sixth report presents measurements of the average sound field around the heads of human talkers. Sound attenuation by an open-office barrier depends on factors other than the height and width of the barrier. To provide more reliable information for modeling open offices, measurements were needed to establish the magnitude of the variations due to factors such as the construction of the screen edge and reflections from the floor. ; Ce rapport présente les mesures d'atténuation acoustique résultant de l'installation d'une barrière entre une source et quatre postes de réception. Le mesurage a été effectué dans un bureau simulé de la chambre anéchoïque de l'IRC pour le compte de Travaux publics et Services gouvernementaux canada (TPSGC). Ce rapport est le quatrième d'une série. Le premier rapport1 présente les mesures de la propagation sonore dans neuf bureaux. Le second rapport2 présente des mesures de niveaux de conversation dans les bureaux. Le troisième rapport3 présente le contexte de l'étude et des informations sur la conception de bureaux à aires ouvertes. Le cinquième rapport4 présente les résultats d'une étude sur l'effet de l'orientation des locuteurs et de la réflectivité des surfaces verticales dans les bureaux à aires ouvertes de style « travail d'équipe » dans un bureau simulé. Le sixième rapport5 présente des mesures du champ sonore moyen autour des têtes des locuteurs. L'atténuation acoustique par une barrière dans les bureaux à aires ouvertes dépend de facteurs autres que sa hauteur et sa largeur. Pour dégager des informations plus fiables sur la modélisation des bureaux à aires ouvertes, d'autres mesurages ont été effectués sur l'amplitude des variations engendrées par des facteurs comme la construction des champs d'écrans de bureaux et les réflexions provenant du sol. ; Peer reviewed: No ; NRC publication: Yes