Institution
Michigan Technological University
Education•Houghton, Michigan, United States•
About: Michigan Technological University is a education organization based out in Houghton, Michigan, United States. It is known for research contribution in the topics: Population & Volcano. The organization has 8023 authors who have published 17422 publications receiving 481780 citations. The organization is also known as: MTU & Michigan Tech.
Topics: Population, Volcano, Catalysis, Asphalt, Computer science
Papers published on a yearly basis
Papers
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Langley Research Center1, Forschungszentrum Jülich2, Leibniz Association3, University of Wyoming4, Max Planck Society5, Leibniz Institute of Marine Sciences6, ETH Zurich7, Earth System Research Laboratory8, University of Mainz9, Princeton University10, National Oceanic and Atmospheric Administration11, University of Bremen12, University of Liège13, Belgian Institute for Space Aeronomy14, University of Saskatchewan15, University of Leeds16, Deutscher Wetterdienst17, Michigan Technological University18, Université libre de Bruxelles19, Karlsruhe Institute of Technology20, University of Denver21
TL;DR: A review of the advances in stratospheric aerosol research can be found in this article, with a focus on the agreement between in situ and space-based inferences of aerosol properties during volcanically quiescent periods.
Abstract: Interest in stratospheric aerosol and its role in climate have increased over the last decade due to the observed increase in stratospheric aerosol since 2000 and the potential for changes in the sulfur cycle induced by climate change. This review provides an overview about the advances in stratospheric aerosol research since the last comprehensive assessment of stratospheric aerosol was published in 2006. A crucial development since 2006 is the substantial improvement in the agreement between in situ and space-based inferences of stratospheric aerosol properties during volcanically quiescent periods. Furthermore, new measurement systems and techniques, both in situ and space based, have been developed for measuring physical aerosol properties with greater accuracy and for characterizing aerosol composition. However, these changes induce challenges to constructing a long-term stratospheric aerosol climatology. Currently, changes in stratospheric aerosol levels less than 20% cannot be confidently quantified. The volcanic signals tend to mask any nonvolcanically driven change, making them difficult to understand. While the role of carbonyl sulfide as a substantial and relatively constant source of stratospheric sulfur has been confirmed by new observations and model simulations, large uncertainties remain with respect to the contribution from anthropogenic sulfur dioxide emissions. New evidence has been provided that stratospheric aerosol can also contain small amounts of nonsulfate matter such as black carbon and organics. Chemistry-climate models have substantially increased in quantity and sophistication. In many models the implementation of stratospheric aerosol processes is coupled to radiation and/or stratospheric chemistry modules to account for relevant feedback processes.
299 citations
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TL;DR: In this paper, global simulations of sulfate, nitrate, and ammonium aerosols are performed for the present day and 2050 using the chemical transport model GEOS-Chem, with the primary focus of the work on future inorganic aerosol levels over the United States.
Abstract: Global simulations of sulfate, nitrate, and ammonium aerosols are performed for the present day and 2050 using the chemical transport model GEOS-Chem. Changes in climate and emissions projected by the IPCC A1B scenario are imposed separately and together, with the primary focus of the work on future inorganic aerosol levels over the United States. Climate change alone is predicted to lead to decreases in levels of sulfate and ammonium in the southeast U.S. but increases in the Midwest and northeast U.S. Nitrate concentrations are projected to decrease across the U.S. as a result of climate change alone. In the U.S., climate change alone can cause changes in annually averaged sulfate-nitrate-ammonium of up to 0.61 μg/m^3, with seasonal changes often being much larger in magnitude. When changes in anthropogenic emissions are considered (with or without changes in climate), domestic sulfate concentrations are projected to decrease because of sulfur dioxide emission reductions, and nitrate concentrations are predicted to generally increase because of higher ammonia emissions combined with decreases in sulfate despite reductions in emissions of nitrogen oxides. The ammonium burden is projected to increase from 0.24 to 0.36 Tg, and the sulfate burden to increase from 0.28 to 0.40 Tg S as a result of globally higher ammonia and sulfate emissions in the future. The global nitrate burden is predicted to remain essentially constant at 0.35 Tg, with changes in both emissions and climate as a result of the competing effects of higher precursor emissions and increased temperature.
299 citations
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TL;DR: Simulations testify the effectiveness of the proposed cooperative sensing approach in multi-hop CR networks and a decentralized consensus optimization algorithm is derived to attain high sensing performance at a reasonable computational cost and power overhead.
Abstract: In wideband cognitive radio (CR) networks, spectrum sensing is an essential task for enabling dynamic spectrum sharing, but entails several major technical challenges: very high sampling rates required for wideband processing, limited power and computing resources per CR, frequency-selective wireless fading, and interference due to signal leakage from other coexisting CRs. In this paper, a cooperative approach to wideband spectrum sensing is developed to overcome these challenges. To effectively reduce the data acquisition costs, a compressive sampling mechanism is utilized which exploits the signal sparsity induced by network spectrum under-utilization. To collect spatial diversity against wireless fading, multiple CRs collaborate during the sensing task by enforcing consensus among local spectral estimates; accordingly, a decentralized consensus optimization algorithm is derived to attain high sensing performance at a reasonable computational cost and power overhead. To identify spurious spectral estimates due to interfering CRs, the orthogonality between the spectrum of primary users and that of CRs is imposed as constraints for consensus optimization during distributed collaborative sensing. These decentralized techniques are developed for both cases of with and without channel knowledge. Simulations testify the effectiveness of the proposed cooperative sensing approach in multi-hop CR networks.
297 citations
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TL;DR: In this article, single-grain laser-fusion analyses of individual sanidine phenocrysts from the two youngest Toba (Indonesia) tuffs yield mean ages of 73 plus minus 4 and 501 plus minus 5 ka.
Abstract: Single-grain laser-fusion {sup 40}Ar/{sup 39}Ar analyses of individual sanidine phenocrysts from the two youngest Toba (Indonesia) tuffs yield mean ages of 73{plus minus}4 and 501{plus minus}5 ka. In addition, glass shards from Toba ash deposited in Malaysia were dated at 68{plus minus}7 ka by the isothermal plateau fission-track technique. These new determinations, in conjunction with previous ages for the two oldest tuffs at Toba, establish the chronology of four eruptive events from the Toba caldera complex over the past 1.2 m.y. Ash-flow tuffs were erupted from the complex every 0.34 to 0.43 m.y., culminating with the enormous (2500-3000 km{sup 3}) Youngest Toba tuff eruption, caldera formation, and subsequent resurgence of Samosir Island. Timing of this last eruption at Toba is coincident with the early Wisconsin glacial advance. The high-precision {sup 40}Ar/{sup 39}Ar age eruption of such magnitude may provide an important marker horizon useful as a baseline for research and modeling of the worldwide climatic impact of exceptionally large explosive eruptions.
297 citations
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TL;DR: The authors argue for an activity-based theory of genre knowledge, drawing on empirical findings from case study research emphasizing "insider knowledge" and on structuration theory, activity-theoretic theory.
Abstract: This article argues for an activity-based theory of genre knowledge. Drawing on empirical findings from case study research emphasizing “insider knowledge” and on structuration theory, activity the...
296 citations
Authors
Showing all 8104 results
Name | H-index | Papers | Citations |
---|---|---|---|
Anil K. Jain | 183 | 1016 | 192151 |
Marc W. Kirschner | 162 | 457 | 102145 |
Yonggang Huang | 136 | 797 | 69290 |
Hong Wang | 110 | 1633 | 51811 |
Fei Wang | 107 | 1824 | 53587 |
Emanuele Bonamente | 105 | 219 | 40826 |
Haoshen Zhou | 104 | 519 | 37609 |
Nicholas J. Turro | 104 | 1131 | 53827 |
Yang Shao-Horn | 102 | 458 | 49463 |
Richard P. Novick | 99 | 295 | 34542 |
Markus J. Buehler | 95 | 609 | 33054 |
Martin L. Yarmush | 91 | 702 | 34591 |
Alan Robock | 90 | 346 | 27022 |
Patrick M. Schlievert | 90 | 444 | 32037 |
Lonnie O. Ingram | 88 | 316 | 22217 |