Institution
York University
Education•Toronto, Ontario, Canada•
About: York University is a education organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Politics. The organization has 18899 authors who have published 43357 publications receiving 1568560 citations.
Papers published on a yearly basis
Papers
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TL;DR: Study of the merit function in the numerical inversion showed that red edge optical indices used in the minimizing function such as R/sub 750//R/sub 710/ perform better than when all single spectral reflectance channels from hyper-spectral airborne CASI data are used, and in addition, the effect of shadows and LAI variation are minimized.
Abstract: Radiative transfer theory and modeling assumptions were applied at laboratory and field scales in order to study the link between leaf reflectance and transmittance and canopy hyper-spectral data for chlorophyll content estimation. This study was focused on 12 sites of Acer saccharum M. (sugar maple) in the Algoma Region, Canada, where field measurements, laboratory-simulation experiments, and hyper-spectral compact airborne spectrographic imager (CASI) imagery of 72 channels in the visible and near-infrared region and up to 1-m spatial resolution data were acquired in the 1997, 1998, and 1999 campaigns. A different set of 14 sites of the same species were used in 2000 for validation of methodologies. Infinite reflectance and canopy reflectance models were used to link leaf to canopy levels through radiative transfer simulation. The closed and dense (LAI>4) forest canopies of Acer saccharum M. used for this study, and the high spatial resolution reflectance data targeting crowns, allowed the use of optically thick simulation formulae and turbid-medium SAILH and MCRM canopy reflectance models for chlorophyll content estimation by scaling-up and by numerical model inversion approaches through coupling to the PROSPECT leaf radiative transfer model. Study of the merit function in the numerical inversion showed that red edge optical indices used in the minimizing function such as R/sub 750//R/sub 710/ perform better than when all single spectral reflectance channels from hyper-spectral airborne CASI data are used, and in addition, the effect of shadows and LAI variation are minimized.
603 citations
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Kavli Institute for Theoretical Physics1, Polish Academy of Sciences2, University of California, Santa Cruz3, University of California, Santa Barbara4, York University5, Princeton University6, Harvard University7, University of Amsterdam8, State University of New York at Oswego9, Northwestern University10, University of Liège11, University of Wisconsin-Madison12, University of Wisconsin–Eau Claire13, Arizona State University14, California Institute of Technology15
TL;DR: In this paper, the capabilities of the open-knowledge software instrument Modules for Experiments in Stellar Astrophysics (MESA) have been updated to improve numerical energy conservation capabilities, including during mass changes.
Abstract: We update the capabilities of the open-knowledge software instrument Modules for Experiments in Stellar Astrophysics (MESA). RSP is a new functionality in MESAstar that models the nonlinear radial stellar pulsations that characterize RR Lyrae, Cepheids, and other classes of variable stars. We significantly enhance numerical energy conservation capabilities, including during mass changes. For example, this enables calculations through the He flash that conserve energy to better than 0.001%. To improve the modeling of rotating stars in MESA, we introduce a new approach to modifying the pressure and temperature equations of stellar structure, as well as a formulation of the projection effects of gravity darkening. A new scheme for tracking convective boundaries yields reliable values of the convective core mass and allows the natural emergence of adiabatic semiconvection regions during both core hydrogen- and helium-burning phases. We quantify the parallel performance of MESA on current-generation multicore architectures and demonstrate improvements in the computational efficiency of radiative levitation. We report updates to the equation of state and nuclear reaction physics modules. We briefly discuss the current treatment of fallback in core-collapse supernova models and the thermodynamic evolution of supernova explosions. We close by discussing the new MESA Testhub software infrastructure to enhance source code development.
601 citations
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TL;DR: In this article, the authors attempt to delineate the boundaries of the term volunteer, and they first reviewed 11 widely used volunteer terms and found that volunteer is used too broadly in denoting nonsalaried service.
Abstract: T1he term volunteer is used too broadly in denoting nonsalaried service. In this article, the authors attempt to delineate the boundaries of the term volunteer. They first reviewed 11 widely used d...
598 citations
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TL;DR: In this paper, the authors examined peer intervention in bullying using naturalistic observations on school playgrounds and found that the majority (57%) of interventions were effective in stopping bullying and that boys were more likely to intervene when the bully and victim were male and girls were female.
Abstract: This study examined peer intervention in bullying using naturalistic observations on school playgrounds. The sample comprised 58 children (37 boys and 21 girls) in Grades 1 to 6 who were observed to intervene in bullying. Peers were present during 88% of bullying episodes and intervened in 19%. In 47% of the episodes, peers intervened aggressively. Interventions directed toward the bully were more likely to be aggressive, whereas interventions directed toward the victim or the bully-victim dyad were more likely to be nonaggressive. The majority (57%) of interventions were effective in stopping bullying. Boys were more likely to intervene when the bully and victim were male and girls when the bully and victim were female. The implications for anti-bullying interventions are discussed.
598 citations
Authors
Showing all 19301 results
Name | H-index | Papers | Citations |
---|---|---|---|
Dan R. Littman | 157 | 426 | 107164 |
Martin J. Blaser | 147 | 820 | 104104 |
Aaron Dominguez | 147 | 1968 | 113224 |
Gregory R Snow | 147 | 1704 | 115677 |
Joseph E. LeDoux | 139 | 478 | 91500 |
Kenneth Bloom | 138 | 1958 | 110129 |
Osamu Jinnouchi | 135 | 885 | 86104 |
Steven A. Narod | 134 | 970 | 84638 |
David H. Barlow | 133 | 786 | 72730 |
Elliott Cheu | 133 | 1219 | 91305 |
Roger Moore | 132 | 1677 | 98402 |
Wendy Taylor | 131 | 1252 | 89457 |
Stephen P. Jackson | 131 | 372 | 76148 |
Flera Rizatdinova | 130 | 1242 | 89525 |
Sudhir Malik | 130 | 1669 | 98522 |