You might have some memory of your childhood... :-)Today in-ear infrared thermometers are quite a fast way to get a good approximation of the body core temp. Go to your MD and ask for your temperature, most probably she will hold such a thermometer into your ear and tell you immediately.
I would be wondering about the infrastructure. For example, what battery would you use? What holds it all while you shove it into your ear? Where do you read out the temperature?
I'm no expert of thermopiles but it looks to me like Arduino / Atmega328 or similar would do the basic job.
You could probably run it off 2 x AA or AAA batteries, the processor can run at a reasonable rate with 3V power.
You probably want to investigate a compact LCD screen to show the temperature, or maybe a couple of 7-segment LEDs, providing you power them off quickly to save power.
To give you an alternative for the sensor:http://shop.boxtec.ch/product_info.php/cPath/39_71/products_id/40658This one offers you medical accuracy (at least in the temperature window of a human body), is read using I2C (you don't have to twiddle with amps and the like, everything included) and is quite focussed (5°). I use it for something similar, although I use it only for a momentary measurement, not for constant wearing.With a clever programming (longer sleep periods) you should be able to drive it from a not to big battery together with a minimal arduino setup (an ATtiny might be enough).
In that case you are talking about 86400 to 172800 readings. Even at a byte each, that is far more than the available EEPROM (1 Kb).You could scale down a bit (a reading every couple of minutes) or get some external storage. An SD card in a small adapter might do the trick, eg.https://www.adafruit.com/products/254Or an EEPROM chip, eg.http://www.gammon.com.au/forum/?id=10990
How can I store and retrieve the temperature readings so that I can analyze them on my computer (about 24 - 48 hours worth, read about once every second, so about 172800 readings, assuming a 2-byte integer, would yield about 337.5 kilobytes of data to store)?
Just how fast do you expect your subject's core body temperature to change?
Just how fast do you expect your subject's core body temperature to change? Once a minute is probably overkill.
That's exactly one of the questions I'm trying to answer!