{
  "schema": "vedokrok.public-item.v1",
  "release_id": "MHC-RPUB-20260920-75ad787a",
  "url": "/knowledge/keep-the-unit-attached-when-moving-the-number",
  "id": "MHC-D-RESEARCH-0983",
  "version": "0.1.0",
  "title": "Keep the unit attached when moving the number",
  "summary": "The number 500 is impressively precise about almost nothing on its own.",
  "kind": "protocol",
  "body": "Carry the unit and the quantity definition with the value. Convert only after confirming that both sides measure the same kind of quantity. A correct conversion cannot repair a comparison between different business definitions.",
  "limits": [
    "Currencies, temperature scales and business-specific units may need context beyond a simple multiplier. Do not improvise safety-critical conversions."
  ],
  "topics": [
    "work-02-data-reconciliation"
  ],
  "intents": [],
  "source_ids": [
    "RS-0C3759023DCB78E8"
  ],
  "evidence": [
    {
      "claim": "UCUM distinguishes unit symbols, prefixes and semantic equivalence so numeric quantities can be interpreted with their units.",
      "source_id": "RS-0C3759023DCB78E8",
      "role": "supports",
      "note": "Compatible physical dimensions do not establish matching business definitions, measurement conditions or conversion dates.",
      "locator": "Unit terms and semantic rules"
    }
  ],
  "use_when": [
    "A value crosses a system boundary, report or manual calculation."
  ],
  "avoid_when": [
    "Currencies, temperature scales and business-specific units may need context beyond a simple multiplier. Do not improvise safety-critical conversions."
  ],
  "example": "A duration of 500 milliseconds becomes 0.5 seconds, not 500 seconds. Separately confirm whether both systems include waiting time.",
  "check": "The receiver can reconstruct the value's meaning and distinguish conversion from a changed measurement definition.",
  "steps": [
    "Record value, unit and what was measured together.",
    "Name the target unit and the documented conversion rule.",
    "Check one known example and preserve the original value for reconciliation."
  ],
  "sources": [
    {
      "id": "RS-0C3759023DCB78E8",
      "title": "The Unified Code for Units of Measure",
      "url": "https://ucum.org/ucum"
    }
  ],
  "relations": [
    {
      "from": "MHC-D-RESEARCH-0983",
      "to": "MHC-D-RESEARCH-0972",
      "type": "useful_with",
      "url": "/knowledge/find-the-first-boundary-where-the-record-becomes-wrong"
    }
  ],
  "collections": [
    {
      "id": "RC-1B134BE48D7DF2A0",
      "title": "Keep the meaning intact when data moves",
      "url": "/collections/keep-the-meaning-intact-when-data-moves"
    }
  ]
}