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Published

April 25

vr.tr.april-25 · thing-q2531

Let an agent handle April 25 as a calendar date with weekday computation, observances attributed to their traditions and sourced events.

Thing Registry Cross-cutting context XCT.TME

Bundle → Layer → Finding → Questions Filled

4 bundles · 8 layers · 8 findings · 16 questions

Date Calendar facts.

Weekday

Computation.

Weekday

Weekday.

  1. On which weekday does April 25 fall in this year? measurement
  2. Is it a leap year? boundary

Calendar

Julian or Gregorian.

Calendar

Calendar system.

  1. Is the Julian or Gregorian calendar meant? boundary
  2. What is the equivalent date in the other calendar? measurement
Observances Holidays.

Holiday

Public holiday.

Holiday

Holiday status.

  1. Is April 25 a public holiday or observance here? provenance
  2. Which tradition or law sets it? provenance

Attribution

Traditions.

Attribution

Attributed observances.

  1. Which countries or communities observe something on this date, according to them? provenance
  2. Is the observance attributed rather than assumed? boundary
History Past events.

Events

On this day.

Events

Historical events.

  1. Which notable events happened on April 25, according to reliable sources? provenance
  2. Are dates given in the same calendar? boundary

Anniversaries

Recurring.

Anniversaries

Anniversaries.

  1. Which anniversaries fall on this date this year? provenance
  2. Which are round numbers? measurement
Planning Scheduling.

Countdown

Days until.

Countdown

Countdown.

  1. How many days until the next April 25? measurement
  2. From which date? definition

Work

Working day.

Work

Working day.

  1. Is it a working day for this organisation? provenance
  2. Do deadlines move? boundary

Classifiers Filled

Family
Thing Registry
Category
Cross-cutting context
Entry kind
thing
Plane
XCT
Domain
XCT.TME

What it is Filled

April 25, day 115 (day 116 in leap years) of the year in the Gregorian calendar, with 250 days remaining in both common and leap years. Observances on this date vary by country and tradition.

Why it exists Filled

Let an agent handle April 25 as a calendar date with weekday computation, observances attributed to their traditions and sourced events.

Distinguishing features Filled

  • The twenty-fifth day of April
  • Weekday varies by year
  • Observances vary by place
  • Julian and Gregorian dates differ by 13 days in this era

What robots and AI may and may not do Filled

Must not

  • Present a national remembrance or liberation day as observed everywhere.
  • Mock or trivialize war remembrance held on April 25.
  • Assign events to this date from unsourced lists.

Only with a human decision

  • Publishing commemorative content in the name of a state or community.

May

  • Compute dates and intervals involving April 25 in the Gregorian calendar.
  • Report observances on this date, such as Anzac Day and Liberation Day in Italy, with the country that holds them.

Moral aspects Filled

  • Remembrance days honour the dead and survivors of war; trivializing them wounds families.
  • Commemorations can carry different meanings for different communities.

Who is affected

  • Veterans and their families
  • People who mark the date
  • Readers of histories

Owners Filled

Steward

Nobody: a calendar date held in common.

Links to other meta-models Filled

parent

  • Q11187339 - registry parent class

related

  • April - month
  • April 24 - date
  • calendar date - category
  • ISO 8601 - notation

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.april-25
  • Wikidata: Q2531 (https://www.wikidata.org/wiki/Q2531)
  • ISO 8601: --04-25 recurring date

Direct properties not applicable Not applicable

  • day of year: 115 or 116 day - common year, leap year where different
  • days remaining: 250 days

Plane XCT: no invented physical properties.

Recognition optional Filled

  • Written 25 April or April 25
  • ISO format --04-25
  • Observances vary by country and tradition
  • A date on calendars.

Capabilities and actions required Filled

  • compute its weekday in a given year
  • check local and international observances
  • find sourced historical events
  • schedule events

Hazards and failure modes required Filled

  • Assuming observances are universal
  • Unsourced on-this-day events
  • Mixing Julian and Gregorian dates

Standards and interfaces required Filled

  • ISO 8601
  • National public holiday laws

Context of use required Filled

  • A calendar date for scheduling, holidays and anniversaries.
  • the recurring calendar date
  • specific dated days in given years

Sources Filled

  1. Wikidata item Q2531: April 25 - identity and sense of the item
  2. Wikipedia: April 25 - general description of the item

Open questions

  • Should dated days be separate entries?
  • How should observances be linked?
  • How should events be sourced?

Machine files

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q2531/spec.json