ISO
8601:2000(E)
4
©
ISO
2000
All
rights
reserved
3.18
recurring
time-interval
series
of
consecutive
time-intervals
of
the
same
duration
3.19
representation,
complete
representation
that
includes
all
the
date
and
time
elements
associated
with
the
expression;
limited,
if
applicable,
by
representations
expressing
the
calendar
year
by
four
digits
3.20
representation,
decimal
expansion
of
a
representation
by
addition
of
a
decimal
fraction
to
the
lowest
order
component
of
the
expression
3.21
representation,
expanded
expansion
of
a
representation
to
allow
identification
of
dates
in
calendar
years
outside
the
range
[0000]
till
[9999]
3.22
representation,
truncated
abbreviation
of
a
representation
by
omission
of
higher
order
components
starting
from
the
left-hand
side
of
the
expression
NOTE
1
See
also
4.6.
NOTE
2
An
expression
for
duration,
in
the
format
with
time-unit
designators,
is
referred
to
as
truncated
if
components
with
value
zero
are
omitted
(see
5.5.3.1).
3.23
representation
with
reduced
precision
abbreviation
of
a
representation
by
omission
of
lower
order
components
starting
from
the
right-hand
side
of
the
expression
3.24
second
basic
unit
of
measurement
of
time
in
the
International
System
of
Units,
(SI)
as
defined
in
ISO
31-1
3.25
second,
leap
intentional
time
step
of
one
second
used
to
adjust
UTC
to
ensure
approximate
agreement
with
UT1
(a
time
scale
based
on
the
rotation
of
the
Earth);
an
inserted
second
is
called
positive
leap
second
and
an
omitted
second
is
called
negative
leap
second
(see
ITU-R
Rec.TF.460-5)
NOTE
A
positive
leap
second
is
inserted
between
23:59:59Z
and
24:00:00Z
and
can
be
represented
as
23:59:60Z.
Negative
leap
seconds
are
achieved
by
the
omission
of
23:59:59Z.
Insertion
or
omission
takes
place
as
determined
by
IERS,
normally
on
June
30th
or
December
31st,
but
if
necessary
on
March
31st
or
September
30th.
3.26
time-point
instant
in
the
laps
of
time
regarded
as
dimensionless
3.27
week
unit
of
time
of
seven
days
3.28
week,
calendar
time-interval
of
seven
days,
starting
on
a
Monday
and
identified
by
its
ordinal
number
within
a
calendar
year
NOTE
A
calendar
week
is
often
also
referred
to
as
week.
