Category: Journal
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OWHL micro SD card current draw tests
As outlined in an earlier post, I found that certain old micro SD cards were performing spectacularly poorly when it came to power consumption because they failed to go into a low-power sleep state immediately after writing data to the card. I recently purchased a few new SanDisk micro SD cards in various capacities to…
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Revised Open Wave Height Logger battery tests
The Open Wave Height Logger is meant to be a submersible pressure logger that will record absolute pressure at 4Hz for several months to give a record of wave height, and ideally do this on a single set of 3 D-cell batteries. I have recently made a few changes to the OWHL software, and discovered…
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The effect of water temperature on whelk drilling speed
Last year I published a little paper showing how whelks (Nucella lapillus) drill through mussel shells at different rates depending on water temperature. This involved making hundreds of hours of recordings of whelks slowly scraping their way through the calcium carbonate shell of Mytilus edulis mussels in different water temperatures. The video above includes two…
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ffmpeg time lapse notes
ffmpeg is a movie-encoding command line tool that is also useful for capturing and assembling time lapse movies, particularly using webcams. Below are some example commands to get it to do stuff. It is run from a terminal command line on Linux, OSX, and Windows. You will probably want to add the location of the…
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Early Open Wave Height Logger battery tests
Following on the previous post about the Open Wave Height Logger project, I’ve been conducting a simple battery life test. One of the prototype OWHLs was powered by a 3 D-cell alkaline battery pack and shoved in the freezer for 32 days. The image below shows the collated daily data files for that time period,…
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Open Wave Height Logger
OWHL – The Open Wave Height Logger OWHL is a project originally dreamed up by Jarrett Byrnes and Ted Lyman at UMass Boston. Early on they contacted me for my thoughts on how to accomplish the goal of making a cheap, long-life pressure sensor data logger that could be used to record ocean wave heights…
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Lizards
Smug looking lizards. They seem awfully contented.
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Thomson Reuters Web of Science is still using OCR text recognition for new citations?
A co-author emailed me the other day to point out that somehow my name had been misspelled in the Web of Science citation database on our recent paper in Ecological Applications. The Web of Science listing has my first name listed as “Luice”, which judging by the name of this here website, isn’t how you…
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Arduino code for MS5803 pressure sensors
I have recently been developing a library for the Measurement Specialties MS5803 line of digital pressure sensors. These sensors are available in several different pressure ranges from 1 to 30 bar, they are submersible if installed in a proper housing, they communicate via I2C or SPI, and they cost around US$35. It’s fairly straightforward to…
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Seastar wasting syndrome
2013 is turning out to be a bad year for seastars (starfish) along the west coast of North America. As documented by this UC Santa Cruz monitoring webpage, a wasting disease of unknown origin (possibly caused by bacteria or a virus) is causing seastars of several species to fall apart. The map provided by the…