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Global Biogeochemical Cycles, 2017
AbstractPhosphorus is believed to be the globally limiting nutrient in the modern ocean, but a number of nutrients have been invoked as limiting the Proterozoic biosphere. Mass balance calculations suggest that Proterozoic net primary productivity must have been 1 to 2 orders of magnitude less than today in order to maintain low oxygen levels despite ...
Thomas A. Laakso, Daniel P. Schrag
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AbstractPhosphorus is believed to be the globally limiting nutrient in the modern ocean, but a number of nutrients have been invoked as limiting the Proterozoic biosphere. Mass balance calculations suggest that Proterozoic net primary productivity must have been 1 to 2 orders of magnitude less than today in order to maintain low oxygen levels despite ...
Thomas A. Laakso, Daniel P. Schrag
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The Limits of the Nonlinear Shannon Limit
Optical Fiber Communication Conference, 2016Recent results about information theoretical limits in optical fibers are reviewed and the significance of what is commonly known as the nonlinear Shannon limit discussed. It is shown that this limit can be improved, while the actual channel capacity at high powers still remains substantially unknown.
SECONDINI, Marco, FORESTIERI, Enrico
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The Journal of the Acoustical Society of America, 1998
Today, traffic noise due to cars, trains, and airplanes is the main noise source in urban areas. In accordance with the European Commission’s Green paper on Future Noise Policy, 22% of the European population are exposed to outdoor A-weighted noise levels higher than 65 dB and more than 45% are exposed to levels between 55 and 65 dB.
Tor Kihlman, Wolfgang Kropp
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Today, traffic noise due to cars, trains, and airplanes is the main noise source in urban areas. In accordance with the European Commission’s Green paper on Future Noise Policy, 22% of the European population are exposed to outdoor A-weighted noise levels higher than 65 dB and more than 45% are exposed to levels between 55 and 65 dB.
Tor Kihlman, Wolfgang Kropp
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The Limitations of “Limitations”
The American Journal of Bioethics, 2004It is heartening to see the authors of “Limitations” (Levine et al. 2004) lamenting that, as a salient concept in research ethics, vulnerability has been a mess.
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Barriers, Limits and Limitations to Resilience
Journal of Extreme Events, 2015Enhancing resilience has become a key element of preparedness for extreme events and climate change. While much progress has been made in defining components of resilience, many questions remain about identification of appropriate strategies for building resilience, barriers to implementation of these strategies, and limits to the potential ...
Robin Leichenko +2 more
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Limited Wegener’s granulomatosis—is it limited?
Clinical Rheumatology, 2007Complete heart block associated with Wegener's granulomatosis (WG) is rare especially in the limited form of the disease. We describe a case of a 43-year-old woman with a limited form of WG who developed a complete heart block. Prompt treatment with steroids and cyclophosphamide led to temporary regression of complete heart block.
Svetlana, Lisitsin +2 more
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2016
The idea that there might be “limits to growth” is a key and contested feature of environmental politics. This chapter outlines the limits to growth thesis, describes and assesses critical reactions to it, and comments upon its relevance today. It argues that, after an initial highpoint in the early 1970s, the thesis declined in importance during the ...
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The idea that there might be “limits to growth” is a key and contested feature of environmental politics. This chapter outlines the limits to growth thesis, describes and assesses critical reactions to it, and comments upon its relevance today. It argues that, after an initial highpoint in the early 1970s, the thesis declined in importance during the ...
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2010
We show that within the Gold paradigm for language learning an informer for a superfinite set can cause an optimal MDL learner to make an infinite amount of mind changes. In this setting an optimal learner can make an infinite amount of wrong choices without approximating the right solution.
Adriaans, P., Mulder, W.
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We show that within the Gold paradigm for language learning an informer for a superfinite set can cause an optimal MDL learner to make an infinite amount of mind changes. In this setting an optimal learner can make an infinite amount of wrong choices without approximating the right solution.
Adriaans, P., Mulder, W.
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Global Discourse, 2019
In his fifth-century BCE chronicle of the Graeco-Persian Wars, Herodotus describes a challenge that European scholars have faced for two and a half millennia (Drace-Francis, 2013: 1). Since Antiquity, discussions of just what ‘Europe’ is, descriptively and normatively, have not been resolved and consensus has been reached that multiple ‘Europes’ exist.
Foster, Russell David, Grzymski, Jan
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In his fifth-century BCE chronicle of the Graeco-Persian Wars, Herodotus describes a challenge that European scholars have faced for two and a half millennia (Drace-Francis, 2013: 1). Since Antiquity, discussions of just what ‘Europe’ is, descriptively and normatively, have not been resolved and consensus has been reached that multiple ‘Europes’ exist.
Foster, Russell David, Grzymski, Jan
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Electrical Engineering, 1934
The amplification obtainable in a vacuum tube amplifier is limited by the noise in the circuit. Of the various sources of noise the most fundamental and inevitable is thermal agitation of electricity. Other sources are the influence of ions and of shot effect and flicker effect on the current in vacuum tubes, poor contacts, mechanical vibration, and ...
J. B. Johnson, F. B. Llewellyn
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The amplification obtainable in a vacuum tube amplifier is limited by the noise in the circuit. Of the various sources of noise the most fundamental and inevitable is thermal agitation of electricity. Other sources are the influence of ions and of shot effect and flicker effect on the current in vacuum tubes, poor contacts, mechanical vibration, and ...
J. B. Johnson, F. B. Llewellyn
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