The SEDRIS Data Representation Model
APPENDIX A - Classes
Absolute Time

Class Name: Absolute Time

Superclass - <Time Point>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies an absolute time in UTC, which is not relative to some other point in time.

The <Absolute Time> class provides

  1. a means to specify an absolute time (UTC) for metadata, and
  2. a general-purpose mechanism for describing points in absolute (UTC) time.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

This class appears on only one page of the DRM class diagram.

Example

  1. Consider a transmittal constructed from a historical database, in which the time at which an event happened is recorded as 1994-10-03T17:56:47Z. In the transmittal, this information is specified by an <Absolute Time> instance with time_significance = SE_TIMESIGNIF_OCCURRENCE as follows.

    time_significance SE_TIMESIGNIF_OCCURRENCE
    time_value.value. ymd_hms.year 1994
    time_value.value. ymd_hms.month SE_MONTH_OCTOBER
    time_value.value. ymd_hms.day 3
    time_value.value. ymd_hms.hour 17
    time_value.value. ymd_hms.minutes 56
    time_value.value. ymd_hms.seconds 47.0
  2. Consider a transmittal for which the data provider wishes to represent the date and time when the transmittal was created. The time value is 2003-03-15T15:18:33Z. The data provider creates an <Absolute Time> instance with time_significance = SE_TIMESIGNIF_CREATION_DATE and the other field values set appropriately as follows.

    time_significance SE_TIMESIGNIF_CREATION_DATE
    time_value.configuration SE_TIMECFG_DATE_YMD_AND_TIME_HMS
    time_value.value. ymd_hms.year 2003
    time_value.value. ymd_hms.month SE_MONTH_MARCH
    time_value.value. ymd_hms.day 23
    time_value.value. ymd_hms.hour 15
    time_value.value. ymd_hms.minutes 18
    time_value.value. ymd_hms.seconds 33.0

    This <Absolute Time> instance is then attached as a component of the <Transmittal Root> instance of the transmittal.

  3. An <Absolute Time> instance is used to specify the date and time of observations.

FAQs

No FAQs supplied.

Constraints

Component of (two-way) (inherited)

Component of (two-way)

Inherited Field Elements

SE_Time_Significance time_significance; 1

Field Elements

SE_Time_Value time_value; 2

Notes

Fields Notes

time_significance

The time_significance field specifies the usage of the time information.

time_value

The time_value field specifies the time value.


Next: Absolute Time Interval. Up:Index.

Last updated: July 26, 2006 Copyright © 2006 SEDRIS