Released On: 10 Jul 2020
Greta Thunberg describes the remarkable and tumultuous past year of her life on a BBC podcast. Hear her description of her visit to the Athabasca Glacier and discussions with John Pomeroy on chapter 6 (30:06).
Read the Time Magazine article: Six Months on a Planet in Crisis: Greta Thunberg’s Travel Diary from the U.S. to Davos, for a full transcription of the podcast here.
Jul 14, 2020
By USask Research Profile and Impact and Mark Ferguson
USask also placed in the top 100 universities in the world in three other research areas: environmental science/engineering (51-75th place), veterinary sciences (51-75th), and agricultural sciences (76-100th), according to the 2020 Shanghai Ranking Consultancy’s ARWU, an influential ranking of 1,800 universities around the world based on research performance indicators such as publications, citation impact, and international collaboration.
“These results are a reflection of the outstanding research that takes place at the University of Saskatchewan as we strive to be the university the world needs,” said USask Vice-President Karen Chad.
“Particularly notable is the fact we are among global leaders in our signature areas of water and food security, as well as in fields such as environmental sciences and new materials research that involve synchrotron-based studies at our Canadian Light Source, Canada’s only synchrotron.”
Read the full article here.
Signal processing for in situ detection of effective heat pulse probe spacing radius as the basis of a self-calibrating heat pulse probe
Nicholas Kinar, John Pomeroy and Bing Si
Published July 16, 2020
Geoscientific Instrumentation, Methods and Data Systems
volume 9, issue 2, pages 293–315
DOI: https://doi.org/10.5194/gi-9-293-2020
Abstract
A sensor comprised of an electronic circuit and a hybrid single and dual heat pulse probe was constructed and tested along with a novel signal processing procedure to determine changes in the effective dual-probe spacing radius over the time of measurement. The circuit utilized a proportional–integral–derivative (PID) controller to control heat inputs into the soil medium in lieu of a variable resistor. The system was designed for onboard signal processing and implemented USB, RS-232, and SDI-12 interfaces for machine-to-machine (M2M) exchange of data, thereby enabling heat inputs to be adjusted to soil conditions and data availability shortly after the time of experiment. Signal processing was introduced to provide a simplified single-probe model to determine thermal conductivity instead of reliance on late-time logarithmic curve fitting. Homomorphic and derivative filters were used with a dual-probe model to detect changes in the effective probe spacing radius over the time of experiment to compensate for physical changes in radius as well as model and experimental error. Theoretical constraints were developed for an efficient inverse of the exponential integral on an embedded system. Application of the signal processing to experiments on sand and peat improved the estimates of soil water content and bulk density compared to methods of curve fitting nominally used for heat pulse probe experiments. Applications of the technology may be especially useful for soil and environmental conditions under which effective changes in probe spacing radius need to be detected and compensated for over the time of experiment.
Read the full article here.