منابع مشابه
Quantification of PM2.5 organic carbon sampling artifacts in US networks
Field blanks (bQF) and backup filters (quartzfiber behind quartz-fiber filter; QBQ) have been adopted by US long-term air quality monitoring networks to estimate PM2.5 organic carbon (OC) sampling artifacts. This study documents bQF and QBQ carbon levels for the: 1) Interagency Monitoring of Protected Visual Environments (IMPROVE); 2) Speciation Trends Network (STN; part of the Chemical Speciat...
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This paper illustrates how artifacts are active elements in the relationships of people and between people and their environments. This does not only mean that they are active in the sense that they are necessary, but also, active in a way that coordinate, and even trigger or initiate, work. The use of artifacts may over time become manifold and not necessarily just serving their initial purpos...
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Purpose: The aim of the study is to characterize the ultrasound and Doppler ultrasound artifact patterns of foreign bodies and to define the role of elastography in their detection. Material and method: Two in-vitro environments including a lamb leg and a lamb stomach coated with ultrasound gel, were prepared. Twenty-seven foreign bodies grouped as metallic, organic and inorganic were evaluated...
متن کاملElectrocardiographic artifacts.
ANSWERS 1. e. none of the above The ECG represents a pseudo-arrhythmia due to artifacts. Two clues direct you to the correct interpretation. The first clue reveals sinus rhythm in lead II. The normal appearance of the complexes in lead II is a result of the cancellation of artifacts and not because of a transient return to normal rhythm. The second clue is that most of the leads show sharp defl...
متن کاملInstructional artifacts
This paper addresses the question if artifacts may be attributed some kind of agency. I take an activity-theoretical and instructional perspective, and argue that artifacts are used to guide actions. In other words, I claim that artifacts have instructional impact. In the introductory part of the paper is given an account of how three kinds of artifacts physical artifacts, linguistic representa...
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ژورنال
عنوان ژورنال: RadioGraphics
سال: 2009
ISSN: 0271-5333,1527-1323
DOI: 10.1148/rg.294085199