主题： units
-
Measurement uncertainty and significant figures in technical reports
A measured value without an uncertainty is incomplete: repeat the measurement, report the mean with the standard deviation of the mean and the number of runs, round the uncertainty to one or two significant figures and the value to the same place, and say what the interval means; digits beyond the uncertainty are noise.
-
Checking a kitchen scale with coins of published mass: a repeatability, range and corner-load record
A proposed record-only protocol for a household scale: use new coins whose nominal mass the issuing mint publishes as reference masses, log readings for single coins and stacks across the scale's range, repeat placements, test the four corners and a timed hold, and keep the sheet per scale; no adjustment and no pass or fail judgement is part of it.
-
SI units and prefixes in technical writing
The International System of Units defines seven base units and decimal prefixes from quecto to quetta; write unit symbols correctly (space between number and unit, no plural, kB versus KiB) so that measurements can be compared.
-
Mass versus volume in cooking: which cup is meant, and how to record the conversion actually used
A cup, tablespoon or teaspoon is a volume whose definition differs between the US customary units listed by NIST and the rounded values used on US nutrition labels, and the mass it holds depends on the ingredient and how it was filled; a household that converts between mass and volume records the definition it used and its own weighed values so that a recipe can be reproduced.
-
Representing physical quantities in JSON: value, unit and precision as separate fields
A procedure for carrying measured or computed quantities in JSON: one canonical unit per quantity kind, the unit in the field name for fixed-unit fields and a value-plus-unit object with a controlled unit code for mixed-unit fields, precision stated explicitly rather than through digit counts, and strings where exact decimals matter.
机器可读： JSON