<s>
A	O
smart	B-Device
device	I-Device
is	O
an	O
electronic	O
device	O
,	O
generally	O
connected	O
to	O
other	O
devices	O
or	O
networks	O
via	O
different	O
wireless	O
protocols	O
(	O
such	O
as	O
Bluetooth	B-Protocol
,	O
Zigbee	B-Protocol
,	O
near-field	O
communication	O
,	O
Wi-Fi	O
,	O
LiFi	O
,	O
or	O
5G	O
)	O
that	O
can	O
operate	O
to	O
some	O
extent	O
interactively	O
and	O
autonomously	O
.	O
</s>
<s>
Several	O
notable	O
types	O
of	O
smart	B-Device
devices	I-Device
are	O
smartphones	B-Application
,	O
smart	B-Device
speakers	I-Device
,	O
smart	O
cars	O
,	O
smart	O
thermostats	O
,	O
smart	O
doorbells	O
,	O
smart	B-Device
locks	I-Device
,	O
smart	O
refrigerators	O
,	O
phablets	B-Application
and	O
tablets	B-Device
,	O
smartwatches	B-Application
,	O
smart	B-Device
bands	I-Device
,	O
smart	O
keychains	O
,	O
smart	B-General_Concept
glasses	I-General_Concept
,	O
and	O
many	O
others	O
.	O
</s>
<s>
The	O
term	O
can	O
also	O
refer	O
to	O
a	O
device	O
that	O
exhibits	O
some	O
properties	O
of	O
ubiquitous	B-Architecture
computing	I-Architecture
,	O
including	O
—	O
although	O
not	O
necessarily	O
—	O
machine	B-Application
learning	I-Application
.	O
</s>
<s>
Smart	B-Device
devices	I-Device
can	O
be	O
designed	O
to	O
support	O
a	O
variety	O
of	O
form	O
factors	O
,	O
a	O
range	O
of	O
properties	O
pertaining	O
to	O
ubiquitous	B-Architecture
computing	I-Architecture
and	O
to	O
be	O
used	O
in	O
three	O
main	O
system	O
environments	O
:	O
physical	O
world	O
,	O
human-centered	O
environments	O
,	O
and	O
distributed	B-Architecture
computing	I-Architecture
environments	O
.	O
</s>
<s>
Boards	O
:	O
meter	O
sized	O
interactive	O
display	O
devices	O
,	O
e.g.	O
,	O
horizontal	O
surface	B-Device
computers	I-Device
and	O
vertical	O
SMART	O
boards	O
.	O
</s>
<s>
These	O
were	O
also	O
envisioned	O
more	O
as	O
information	B-Device
appliances	I-Device
.	O
</s>
<s>
If	O
each	O
of	O
these	O
three	O
characteristics	O
is	O
relaxed	O
,	O
this	O
range	O
can	O
be	O
expanded	O
into	O
a	O
much	O
more	O
diverse	O
and	O
potentially	O
more	O
useful	O
range	O
of	O
ubiquitous	B-Architecture
computing	I-Architecture
devices	O
.	O
</s>
<s>
Smart	B-Device
devices	I-Device
are	O
typically	O
composed	O
of	O
a	O
hardware	O
layer	O
(	O
including	O
a	O
radio	O
that	O
transmits	O
signals	O
)	O
,	O
a	O
network	O
layer	O
(	O
through	O
which	O
devices	O
communicate	O
with	O
each	O
other	O
)	O
,	O
and	O
an	O
application	O
layer	O
(	O
through	O
which	O
end	O
users	O
deliver	O
commands	O
)	O
.	O
</s>
<s>
Dynamic	O
component-oriented	O
resource	O
extensions	O
&	O
plug-ins	O
(	O
plug	B-Device
and	I-Device
play	I-Device
)	O
of	O
some	O
hardware	O
resources	O
.	O
</s>
<s>
Access	O
to	O
specific	O
external	O
environments	O
:	O
human	O
interaction	O
,	O
physical	O
world	O
interaction	O
and	O
distributed	O
ICT	O
/	O
virtual	B-Architecture
computing	I-Architecture
interaction	O
.	O
</s>
<s>
Some	B-Architecture
ubiquitous	I-Architecture
computing	I-Architecture
properties	O
.	O
</s>
<s>
Common	O
types	O
of	O
smart	B-Device
devices	I-Device
include	O
:	O
</s>
<s>
Weiser	O
's	O
vision	O
for	O
ubiquitous	B-Architecture
computing	I-Architecture
can	O
be	O
summarized	O
in	O
terms	O
of	O
two	O
core	O
properties	O
:	O
</s>
<s>
It	O
is	O
proposed	O
that	O
there	O
are	O
two	O
additional	O
core	O
types	O
of	O
properties	O
for	O
ubiquitous	B-Architecture
computing	I-Architecture
systems	O
:	O
</s>
<s>
This	O
may	O
entail	O
some	O
form	O
of	O
artificial	B-Application
intelligence	I-Application
in	O
order	O
to	O
:	O
</s>
<s>
However	O
,	O
it	O
is	O
hard	O
to	O
fix	O
a	O
closed	O
set	O
of	O
properties	O
that	O
define	O
all	O
ubiquitous	B-Architecture
computing	I-Architecture
devices	O
because	O
of	O
the	O
sheer	O
range	O
and	O
variety	O
of	O
ubiquitous	B-Architecture
computing	I-Architecture
research	O
and	O
applications	O
.	O
</s>
<s>
Rather	O
than	O
to	O
propose	O
a	O
single	O
definition	O
for	O
ubiquitous	B-Architecture
computing	I-Architecture
,	O
a	O
taxonomy	O
of	O
properties	O
for	O
ubiquitous	B-Architecture
computing	I-Architecture
has	O
been	O
proposed	O
,	O
from	O
which	O
different	O
kinds	O
or	O
flavours	O
of	O
ubiquitous	O
systems	O
and	O
applications	O
can	O
be	O
composed	O
and	O
described	O
.	O
</s>
<s>
The	O
term	O
smart	B-Device
device	I-Device
environments	O
has	O
two	O
meanings	O
.	O
</s>
<s>
Virtual	B-Architecture
computing	I-Architecture
environments	O
that	O
enable	O
smart	B-Device
devices	I-Device
to	O
access	O
pertinent	O
services	O
anywhere	O
and	O
anytime	O
.	O
</s>
<s>
Physical	O
environments	O
that	O
may	O
be	O
embedded	O
with	O
a	O
variety	O
of	O
smart	B-Device
devices	I-Device
of	O
different	O
types	O
including	O
tags	O
,	O
sensors	O
and	O
controllers	O
.	O
</s>
<s>
However	O
,	O
humans	O
may	O
themselves	O
be	O
accompanied	O
by	O
smart	B-Device
devices	I-Device
such	O
as	O
mobile	O
phones	O
,	O
use	O
surface-mounted	O
devices	O
(	O
wearable	B-Operating_System
computing	I-Operating_System
)	O
and	O
contain	O
embedded	B-Architecture
devices	I-Architecture
(	O
e.g.	O
,	O
pacemakers	B-Device
to	O
maintain	O
a	O
healthy	O
heart	O
operation	O
)	O
.	O
</s>
<s>
Second	O
,	O
the	O
term	O
smart	B-Device
device	I-Device
environments	O
can	O
also	O
refer	O
to	O
the	O
concept	O
of	O
a	O
smart	O
environment	O
which	O
focuses	O
more	O
specifically	O
on	O
the	O
physical	O
environment	O
of	O
the	O
device	O
.	O
</s>
<s>
The	O
physical	O
environment	O
is	O
smart	O
because	O
it	O
is	O
embedded	O
or	O
scattered	O
with	O
smart	B-Device
devices	I-Device
that	O
can	O
sense	O
and	O
control	O
part	O
of	O
it	O
.	O
</s>
