Best Practices of Ag Weather Measurement with Bruce Bugbee скачать в хорошем качестве

Best Practices of Ag Weather Measurement with Bruce Bugbee

Bruce Bugbee, President of Apogee Instruments and professor of Crop Physiology at Utah State University, talks about some best practices of Agriculture Weather Measurement at the Campbell Scientific Partners Conference in Logan, Utah on October 3, 2018. Topics include air temperature sensors (PRT, thermistors, thermocouples, aspirated shields), radiation frost, net radiometers, pyranometers, quantum PAR sensors, and other various topics. VIDEO CONTENT 00:48 Instrumentation Class (1) Have some understanding of the physics of signal transduction (2) Interfacing sensors to dataloggers (3) Programming the datalogger. 02:46 How do you decide what new sensors to work on (at Apogee)? 06:20 First quantum meter Apogee ever built. 07:11 Bruce’s first cell phone. 07:36 Simplest measurement of temperature and the simplest measurement of air temperature. What we really need to know to determine energy balance and plant canopies and irrigation requirements of crops is the leaf to air temperature difference. We realized the air temperatures were wrong when they were measured in a standard, multi-plate static shield. 10:42 What sensor would you use to measure temperature? 12:15 Thermistors vs. PRTs. Small is better because they stay in equilibrium with the air temperature better. 14:13 PRTs are not created equal. PRTs vs. Epoxy bead thermistor. 17:34 Reasons thermistors drift: (1) high temperatures (2) moisture. It’s possible to make thermistors very stable. 19:04 The hidden cost of sensors. How many channels on a datalogger does your sensor take up? 20:56 Data comparing epoxy bead thermistor vs. PRTs during accelerated aging tests. Thermistors can be impressively stable if they are encased correctly. 25:20 The importance of aspirated shields. Aspirated shields vs. static shields. 36:35 Sensors and shields. Temperature monitoring in fruit orchards. 39:17 Cache Valley Atmospheric Mixing Project. 41:20 What are some of the instruments that you are most interested in? Leaf and bud sensors. A low-cost way to estimate bud temperatures. What radiation can do to surface temperatures. 48:16 A few things about humidity. Capacitance humidity sensors. 52:19 Solar radiation. 57:23 Net radiometers. 1:00:25 Questions for Bruce.