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Full-Text Articles in Atmospheric Sciences
Urban Flow And Small Unmanned Aerial System Operations In The Built Environment, Kevin A. Adkins
Urban Flow And Small Unmanned Aerial System Operations In The Built Environment, Kevin A. Adkins
Kevin A. Adkins, PhD
The Federal Aviation Administration (FAA) has put forth a set of regulations (Part 107) that govern small unmanned aerial system (sUAS) operations. These regulations restrict unmanned aircraft (UA) from flying over people and their operation to within visual line of sight (VLOS). However, as new applications for unmanned aerial systems (UAS) are discovered, their capabilities improve, and regulations evolve, there is an increasing desire to undertake urban operations, such as urban air mobility, package delivery, infrastructure inspection, and surveillance. This built environment poses new weather hazards that include enhanced wind shear and turbulence. The smaller physical dimensions, lower mass and …
Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker
Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker
Xiaoyang Zhang
The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age,aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the MODIS sensors. …
Horizontal Phase Speed Distribution Of Gravity Waves Observed In Mesospheric Temperature Maps, Ahmad Talaei, Mike Taylor, Pierre-Dominique Pautet, Yucheng Zhao, Takashi S. Matsuda, Takuji Nakamura
Horizontal Phase Speed Distribution Of Gravity Waves Observed In Mesospheric Temperature Maps, Ahmad Talaei, Mike Taylor, Pierre-Dominique Pautet, Yucheng Zhao, Takashi S. Matsuda, Takuji Nakamura
Ahmad Talaei
The goal of the current work is to develop a method suitable for analyzing the horizontal phase speeds of atmospheric gravity waves from an extensive amount of gravity wave data obtained by the USU Advanced Mesospheric Temperature Mapper (AMTM) from Logan, Utah and South Pole, Antarctica. AMTM is a novel infrared digital imaging system that measures selected emission lines in the mesospheric OH (3,1) band to create intensity and temperature maps of the mesosphere. This analysis builds on the recent work by Matsuda et al. using all-sky (180° field-of-view) intensity data to investigate the gravity waves horizontal phase speed distribution. …
Approaches To Mitigating Decayed Buried Timber Within Railway Embankments, Barry A. Palynchuk Phd
Approaches To Mitigating Decayed Buried Timber Within Railway Embankments, Barry A. Palynchuk Phd
Barry A. Palynchuk PhD
During the last three years, several sinkholes have been observed along CPR railway lines in Southern Ontario. The sinkholes have formed as a result of the decay of buried timber trestles in railway embankments. Although it has not occurred the sinkholes could result in hazardous changes in track geometry under load. This study summarizes the site investigation results and remedial methods implemented at five sites in southern Ontario. Remedial methods include placement geosynthetic reinforcement, soil-cement column reinforcement and grouting of voids at the trestle bents. The design, installation methods and construction constraints for the remedial options are described in this …
Comparison Between Analytical Probabilistic And Computer Simulation Models, Using Current Design Examples, Barry A. Palynchuk Phd
Comparison Between Analytical Probabilistic And Computer Simulation Models, Using Current Design Examples, Barry A. Palynchuk Phd
Barry A. Palynchuk PhD
Closed form analytical expressions have been developed to solve several basic problems related to the hydrologic design of storm water management facilities. The collection of these analytical expressions is referred to as the Analytical Probabilistic Storm Water Models (APSWM). APSWM can be used as an alternative to the design storm simulation models in the design and analysis of storm water management facilities. In this paper, a comparison is made between APSWM and design storm simulation models as applied to an actual design case. Conventional outputs such as runoff volume, peak discharge, and peak discharge from detention ponds are reviewed and …