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C
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m
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1.
I
NT
RO
D
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I
O
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W
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liv
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in
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w
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s
[
1
]
–
[
4
]
an
d
m
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d
ev
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[
5
]
–
[
9
]
u
s
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[
1
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ates
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p
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[
1
3
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–
[
1
5
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.
T
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[
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,
[
1
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.
T
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2.
E
VO
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lab
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tech
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t
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ied
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s
.
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h
e
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ir
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t d
i
s
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v
er
y
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t
ar
ted
in
1
7
9
4
w
h
e
n
p
h
y
s
io
lo
g
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s
t
L
az
za
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y
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m
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n
g
b
ats.
I
n
1
8
7
7
,
J
ac
q
u
es a
n
d
P
ier
r
e
d
is
co
v
er
ed
th
e
p
iezo
elec
tr
ic
ef
f
ec
t
w
h
ic
h
w
as
u
s
e
d
in
t
h
e
tr
a
n
s
d
u
ce
r
s
d
esig
n
f
o
r
u
ltra
s
o
n
ic
w
av
e
s
in
air
an
d
w
ater
[
1
8
]
.
T
h
e
s
u
cc
es
s
f
u
l
ap
p
licatio
n
o
f
p
iez
o
elec
tr
icit
y
i
n
t
h
e
g
en
er
atio
n
an
d
d
etec
tio
n
o
f
u
ltra
s
o
u
n
d
w
a
v
es
i
n
d
ee
p
s
e
a
w
ater
w
a
s
f
o
llo
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ed
b
y
f
u
r
t
h
er
d
ev
elo
p
m
e
n
t
a
s
d
escr
ib
ed
in
[
1
8
]
–
[
2
0
]
.
T
h
e
fi
r
s
t
te
ch
n
o
lo
g
ica
l
ap
p
licatio
n
o
f
u
ltra
s
o
u
n
d
d
ates
b
ac
k
i
n
1
9
1
6
w
h
ic
h
w
as
in
s
p
ir
ed
b
y
th
e
s
in
k
i
n
g
o
f
T
itan
ic
s
h
ip
ea
r
lier
b
ef
o
r
e
w
h
en
P
au
l
L
an
g
e
v
i
n
w
as
tr
y
in
g
to
d
etec
t
s
u
b
m
ar
i
n
es
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s
i
n
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o
u
n
d
n
av
ig
atio
n
a
n
d
r
an
g
i
n
g
tec
h
n
o
lo
g
y
a
ls
o
k
n
o
w
n
as SON
AR
[
2
1
]
,
[
2
2
]
.
T
o
d
ay
,
th
e
d
ev
elo
p
m
en
t
o
f
u
ltra
s
o
u
n
d
tech
n
o
lo
g
y
i
s
u
s
e
d
in
m
a
n
y
ar
ea
s
o
f
lif
e,
esp
ec
iall
y
in
telec
o
m
m
u
n
icatio
n
[
2
3
]
,
[
2
4
]
,
h
ea
v
y
in
d
u
s
tr
y
[
2
5
]
–
[
2
7
]
an
d
b
io
m
e
d
ical
i
m
a
g
i
n
g
[
2
8
]
,
[
2
9
]
.
T
h
e
f
r
eq
u
e
n
c
y
r
an
g
e
o
f
u
ltra
s
o
n
i
c
is
v
er
y
w
id
e
a
n
d
d
ep
en
d
s
o
n
t
h
eir
u
s
e,
r
an
g
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n
g
f
r
o
m
2
0
k
Hz
i
n
i
n
d
u
s
tr
ial
d
e
v
ices
u
p
to
1
0
MH
z
i
n
m
ed
ic
al
d
iag
n
o
s
tics
an
d
th
er
ap
y
.
2
.
2
.
Ult
r
a
s
o
nic in M
o
dern
C
o
m
p
ute
r
Sy
s
t
e
m
T
h
e
co
n
ce
p
t
o
f
tr
an
s
f
er
r
in
g
d
ata
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v
er
in
au
d
ib
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s
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n
d
s
ig
n
al
w
it
h
i
n
h
i
g
h
f
r
eq
u
e
n
c
y
r
an
g
e
o
r
s
im
p
l
y
k
n
o
w
n
a
s
u
ltra
s
o
n
ic
d
ata
tr
an
s
m
i
s
s
io
n
co
v
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a
w
id
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g
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o
f
p
r
ac
tical
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s
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s
.
A
co
m
m
o
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w
a
y
to
s
e
n
d
d
ig
ita
l
d
ata
u
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u
r
n
i
n
g
o
n
an
d
o
f
f
t
h
e
tr
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m
itter
.
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h
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n
t
h
e
r
ec
eiv
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g
s
en
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o
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d
etec
ts
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co
r
r
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d
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g
ch
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o
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s
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n
d
p
r
ess
u
r
e,
th
is
i
n
f
o
r
m
atio
n
c
an
b
e
co
n
v
er
t
ed
b
ac
k
in
to
an
elec
tr
ical
s
ig
n
al
an
d
tr
an
s
lated
b
ac
k
to
t
h
e
o
r
i
g
in
al
d
ata.
Dig
i
tal
d
ata
ca
n
b
e
r
ep
r
esen
ted
b
y
a
s
er
ies
o
f
u
ltra
s
o
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n
d
b
u
r
s
t
s
tr
a
v
elli
n
g
as
p
r
ess
u
r
e
w
a
v
es
th
r
o
u
g
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air
.
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h
e
s
o
u
n
d
s
i
g
n
al
t
h
at
ab
le
to
ca
r
r
y
s
e
n
s
iti
v
e
d
ata
i
m
p
o
s
ed
m
an
y
o
p
p
o
r
tu
n
i
ties
an
d
th
r
ea
t
s
[
3
0
]
.
T
r
an
s
m
itti
n
g
an
y
t
h
i
n
g
i
n
a
lo
w
f
r
eq
u
e
n
c
y
r
a
n
g
e
o
f
u
ltra
s
o
n
ic
ca
n
b
e
co
n
s
i
d
er
ed
ex
p
o
s
in
g
t
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d
ata
p
u
b
licl
y
b
u
t
is
h
id
d
en
b
y
an
y
o
n
e
n
o
t
lo
o
k
i
n
g
f
o
r
it.
No
w
ad
a
y
s
m
o
s
t
m
o
d
er
n
co
m
p
u
t
er
s
s
u
ch
as
lap
to
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s
an
d
m
o
b
ile
p
h
o
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a
v
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u
il
t
in
m
icr
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a
n
d
s
p
ea
k
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s
.
T
h
is
m
ea
n
s
t
h
at
i
n
t
h
e
ab
s
en
c
e
o
f
n
et
w
o
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k
ca
b
le
s
an
d
w
ir
eless
s
ig
n
al,
t
h
o
s
e
b
u
il
t in
d
ev
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s
ca
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b
e
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til
ized
to
co
n
tr
o
l th
o
s
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s
y
s
te
m
s
m
al
icio
u
s
l
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.
Fo
r
co
m
p
u
ter
s
y
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te
m
,
a
m
o
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g
th
e
ea
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lies
t
tech
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lo
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t
h
at
b
ec
o
m
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g
r
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i
n
ter
est
a
m
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co
m
p
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en
g
i
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ee
r
s
f
o
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d
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tr
a
n
s
m
i
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s
io
n
o
v
er
s
o
u
n
d
is
au
d
io
w
a
ter
m
ar
k
i
n
g
.
T
h
e
co
n
ce
p
t
o
f
w
at
er
m
ar
k
i
n
g
o
r
h
id
i
n
g
d
ata
in
s
o
u
n
d
s
i
g
n
al
h
as
s
tar
te
d
to
r
ec
eiv
e
in
ter
est
a
m
o
n
g
p
r
o
f
ess
io
n
als
s
i
n
ce
y
ea
r
1
9
9
6
[
3
1
]
.
T
h
e
f
ac
t
th
at
th
e
li
m
ita
tio
n
o
f
th
e
o
ld
co
n
ce
p
t
ca
n
o
n
l
y
tr
an
s
m
it
ab
o
u
t
o
n
e
ch
ar
ac
ter
p
er
s
ec
o
n
d
,
m
o
r
e
d
e
v
elo
p
m
e
n
t
h
as
b
ee
n
d
o
n
e
v
ia
tech
n
iq
u
es
u
s
i
n
g
u
l
tr
aso
n
ic
s
i
g
n
als
w
h
ic
h
ca
n
tr
an
s
m
it
i
n
f
o
r
m
atio
n
at
h
i
g
h
er
s
p
ee
d
s
[
3
2
]
–
[
3
4
]
.
Ultr
aso
n
ic
d
ata
tr
a
n
s
m
i
s
s
io
n
i
n
s
h
o
r
t
r
an
g
e
also
k
n
o
w
n
a
s
n
ea
r
-
s
o
u
n
d
d
ata
tr
an
s
f
er
(
NS
DT
)
en
ab
les
s
ec
u
r
e
tr
an
s
ac
tio
n
s
b
y
cr
ea
ti
n
g
a
n
el
ec
tr
o
n
ic
s
ig
n
at
u
r
e
u
s
in
g
a
o
n
e
-
ti
m
e
p
ass
w
o
r
d
th
r
o
u
g
h
in
a
u
d
ib
le
au
d
io
s
ig
n
al
o
f
a
m
o
b
ile
d
ev
ice.
T
h
is
tec
h
n
o
lo
g
y
i
s
p
r
i
m
ar
il
y
u
s
ed
f
o
r
m
o
b
ile
b
an
k
i
n
g
ca
n
b
e
v
er
y
d
elica
te
as
r
an
g
e
o
f
m
ea
s
u
r
e
m
e
n
t
ca
n
b
e
af
f
ec
te
d
b
y
air
fl
o
w
,
te
m
p
er
atu
r
e
c
h
an
g
es,
h
u
m
id
it
y
o
r
en
v
ir
o
n
m
en
tal
s
i
g
n
a
l
[
3
5
]
.
S
m
ar
ter
d
esi
g
n
s
c
h
e
m
e
n
ee
d
t
o
b
e
d
ev
elo
p
ed
to
d
eliv
er
s
tealth
y
co
m
m
u
n
ica
tio
n
u
tili
z
in
g
u
ltra
s
o
n
ic
f
r
eq
u
e
n
c
y
r
an
g
e.
Fo
r
lo
n
g
d
is
tan
ce
tr
ac
k
in
g
,
m
u
ltip
le
u
l
tr
aso
n
ic
s
e
n
s
o
r
s
ar
e
ad
o
p
ted
to
r
ea
lize
ex
ac
tly
lo
ca
t
in
g
m
o
tio
n
o
b
j
ec
ts
w
it
h
s
o
p
h
is
t
icate
d
s
c
h
e
m
e
m
ea
s
u
r
i
n
g
t
h
eir
m
o
tio
n
o
r
ien
tatio
n
s
o
th
at
t
h
eir
2
D
co
o
r
d
in
ates
s
h
o
u
ld
b
e
lo
ca
ted
an
d
p
o
s
itio
n
ed
[
3
6
]
.
L
atest is
s
u
e
h
a
s
f
o
c
u
s
ed
o
n
t
h
e
cr
o
s
s
-
d
ev
ice
tr
ac
k
i
n
g
w
h
ich
b
r
in
g
a
s
er
i
o
u
s
th
r
ea
t
to
th
e
p
r
iv
ac
y
o
f
u
s
er
s
.
A
r
ec
en
t
p
r
ac
tice
e
m
b
ed
s
u
ltra
s
o
n
i
c
b
ea
co
n
s
in
au
d
io
d
ev
ice
an
d
tr
ac
k
s
th
e
m
u
s
in
g
th
e
m
icr
o
p
h
o
n
e
o
f
m
o
b
ile
d
ev
ices.
R
e
s
ea
r
ch
er
s
h
av
e
e
x
p
lo
r
ed
th
ese
n
e
w
tr
ac
k
i
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g
tech
n
o
lo
g
ies
b
ased
o
n
th
e
ca
p
ab
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ies,
p
er
v
asi
v
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e
s
s
a
n
d
t
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h
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ical
li
m
itatio
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o
f
e
x
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s
tin
g
co
m
m
er
cial
tr
ac
k
i
n
g
s
o
lu
tio
n
s
[
3
7
]
–
[
3
9
]
.
Fig
u
r
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1
illu
s
tr
ate
th
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d
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o
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f
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.
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Fig
u
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m
p
u
ter
s
o
r
th
o
s
e
w
it
h
o
u
t
p
h
y
s
ical
ac
c
ess
i
s
s
til
l
co
n
s
id
er
ed
a
ch
allen
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n
g
tas
k
.
Am
o
n
g
o
th
er
t
y
p
e
o
f
co
m
p
u
t
er
s
ec
u
r
it
y
at
tack
w
h
ic
h
ex
p
lo
i
t a
n
d
ex
f
iltra
te
d
ata
f
r
o
m
air
-
g
ap
p
ed
co
m
p
u
ter
s
w
it
h
o
u
t
r
eq
u
ir
i
n
g
n
e
t
w
o
r
k
co
n
n
ec
t
iv
i
t
y
is
th
e
co
v
er
t
c
h
an
n
el.
I
t
s
tar
ted
o
f
f
a
s
g
r
ea
t
d
eb
u
t
i
n
ea
r
l
y
y
ea
r
o
f
1
9
8
0
s
an
d
h
av
e
b
ee
n
w
id
el
y
d
is
c
u
s
s
ed
in
p
r
o
f
e
s
s
io
n
al
l
iter
atu
r
e
[
4
0
]
–
[
4
2
]
.
Dif
f
er
en
t
t
y
p
es
o
f
o
u
t
-
of
-
b
an
d
co
v
er
t
ch
an
n
els
h
a
v
e
b
ee
n
p
r
o
p
o
s
ed
o
v
er
th
e
y
ea
r
s
,
e
x
p
lo
r
in
g
t
h
e
f
ea
s
ib
ilit
y
o
f
d
ata
ex
f
iltra
tio
n
t
h
r
o
u
g
h
a
n
air
-
g
ap
.
Fo
r
ex
a
m
p
le,
t
h
e
o
ld
est
k
in
d
o
f
co
v
er
t c
h
a
n
n
el
r
esear
c
h
ed
ar
e
li
k
el
y
to
b
e
th
e
elec
tr
o
m
a
g
n
etic
m
eth
o
d
s
th
at
ex
p
lo
it
elec
tr
o
m
ag
n
eti
c
r
ad
iatio
n
f
r
o
m
d
if
f
er
e
n
t
c
o
m
p
o
n
en
t
s
o
f
t
h
e
co
m
p
u
ter
[
4
3
]
,
[
4
4
]
.
P
r
ev
io
u
s
l
y
d
ata
ex
f
iltra
tio
n
u
s
in
g
au
d
ib
le
a
n
d
in
a
u
d
ib
le
s
o
u
n
d
h
a
s
b
ee
n
p
r
o
p
o
s
ed
an
d
ex
p
lo
r
ed
[
4
5
]
–
[
4
7
]
.
L
o
o
k
in
g
b
ac
k
o
v
er
a
d
ec
ad
e,
r
esear
ch
er
s
p
r
o
p
o
s
ed
an
'
au
d
io
n
et
w
o
r
k
i
n
g
,
'
w
h
ic
h
allo
w
s
d
ata
tr
an
s
m
is
s
io
n
b
et
w
ee
n
a
p
air
o
f
d
esk
to
p
co
m
p
u
ter
s
,
u
s
i
n
g
ch
e
ap
s
p
ea
k
er
s
an
d
a
m
icr
o
p
h
o
n
e
[
4
5
]
.
T
h
e
ex
is
tin
g
m
et
h
o
d
s
h
o
w
s
t
h
at
d
ata
ca
n
b
e
tr
an
s
m
itted
th
r
o
u
g
h
th
e
air
-
g
ap
v
ia
u
ltra
s
o
n
ic
s
i
g
n
al
e
m
it
ted
f
r
o
m
co
m
p
u
ter
s
p
ea
k
er
s
.
Fo
r
i
n
s
tan
ce
,
r
ec
e
n
t
w
o
r
k
in
[
4
6
]
s
u
g
g
e
s
t
a
m
eth
o
d
o
f
tr
an
s
m
itti
n
g
k
e
y
s
tr
o
k
e
d
a
ta
u
s
in
g
a
m
al
w
ar
e
vi
a
u
ltra
s
o
n
ic
a
u
d
io
e
m
itted
f
r
o
m
co
m
p
u
ter
s
p
ea
k
er
s
.
T
h
e
r
e
s
ea
r
ch
er
s
p
r
o
p
o
s
ed
a
m
et
h
o
d
f
o
r
n
ea
r
-
u
ltra
s
o
n
i
c
in
co
v
er
t
n
et
w
o
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k
i
n
g
a
m
o
n
g
air
-
g
ap
p
ed
co
m
p
u
ter
s
w
i
th
a
2
0
b
it
p
er
s
ec
o
n
d
s
p
ee
d
at
a
d
is
tan
ce
u
p
to
1
9
.
7
m
u
s
i
n
g
o
n
l
y
s
p
ea
k
er
s
an
d
m
icr
o
p
h
o
n
es.
T
h
ey
w
er
e
ab
le
h
av
e
a
k
e
y
lo
g
g
er
tr
an
s
m
itt
in
g
r
ec
o
r
d
ed
k
e
y
s
tr
o
k
e
s
ac
r
o
s
s
a
co
m
p
u
ter
s
’
m
es
h
n
e
t
an
d
co
llect
th
e
k
e
y
s
tr
o
k
es
o
f
th
e
p
r
i
m
ar
y
v
ict
i
m
co
m
p
u
ter
o
n
r
e
m
o
te
s
y
s
te
m
.
An
o
th
er
r
ec
en
t
w
o
r
k
h
a
s
s
tu
d
i
ed
d
ata
leak
a
g
e
f
r
o
m
a
h
i
g
h
-
s
ec
u
r
it
y
o
f
an
air
-
g
ap
p
ed
s
y
s
te
m
to
a
lo
w
-
s
ec
u
r
it
y
n
et
w
o
r
k
s
y
s
te
m
s
u
s
in
g
m
al
war
e
v
ia
h
ig
h
f
r
eq
u
en
c
y
s
i
g
n
al
w
it
h
i
n
is
o
lated
in
ter
n
et
en
v
i
r
o
n
m
e
n
t
[
4
7
]
.
T
h
e
r
esear
ch
er
s
d
e
m
o
n
s
tr
ated
h
o
w
th
e
m
al
w
ar
e
i
n
s
tal
led
o
n
t
h
e
air
-
g
ap
co
m
p
u
ter
co
llected
d
ata,
co
n
v
er
ted
it
i
n
to
b
in
ar
y
a
n
d
t
h
en
b
lin
k
ed
L
E
D
ac
co
r
d
in
g
l
y
.
A
t t
h
e
s
a
m
e
ti
m
e
,
th
e
i
n
f
ec
ted
ca
m
er
a
ca
p
tu
r
ed
th
i
s
p
atter
n
an
d
t
h
e
m
al
w
ar
e
i
n
s
ta
lled
o
n
t
h
e
ca
m
er
a
co
n
v
er
ted
th
e
Mo
r
s
e
-
co
d
e
b
ac
k
in
to
t
h
e
b
i
n
ar
y
d
ata.
T
h
ese
co
n
f
ir
m
t
h
e
v
alid
it
y
o
f
t
h
e
co
n
ce
r
n
t
h
at
u
lt
r
aso
n
ic
d
ata
tr
an
s
m
i
s
s
io
n
b
et
w
ee
n
s
y
s
te
m
s
is
a
s
ec
u
r
it
y
t
h
r
ea
t.
Data
co
m
m
u
n
icatio
n
o
v
er
i
n
au
d
ib
le
s
o
u
n
d
s
h
as
b
ee
n
ex
p
lo
r
ed
an
d
ex
te
n
d
ed
f
o
r
d
if
f
er
en
t
en
v
ir
o
n
m
e
n
t
u
s
in
g
lap
to
p
s
an
d
s
m
ar
tp
h
o
n
es
[
4
8
]
,
[
4
9
]
.
Hig
h
s
ec
u
r
it
y
o
r
g
an
izatio
n
s
d
o
em
p
lo
y
co
n
tr
o
ls
th
a
t
p
r
ev
en
t
r
ad
io
s
ig
n
als
f
r
o
m
p
r
o
p
ag
atin
g
i
n
to
o
r
o
u
t
o
f
th
e
b
u
i
ld
in
g
.
An
i
n
ter
esti
n
g
co
n
ce
p
t
o
f
tr
an
s
m
it
tin
g
d
ata
ac
r
o
s
s
s
o
lid
m
etal
m
ed
i
u
m
s
v
ia
u
l
tr
aso
n
ic
tr
an
s
d
u
ce
r
s
t
h
at
w
o
u
ld
o
th
er
w
is
e
b
lo
ck
r
ad
io
s
ig
n
al
s
ab
le
to
ac
h
iev
e
u
ltra
s
o
n
ic
d
ata
tr
an
s
m
is
s
io
n
v
ia
Fre
q
u
e
n
c
y
-
S
h
i
f
t
Ke
y
i
n
g
(
F
SK)
w
ith
a
b
it
r
ate
o
f
u
p
to
8
0
0
b
its
p
er
s
ec
o
n
d
[
5
0
]
.
Ho
w
ev
er
,
it d
o
es
n
o
t e
m
p
lo
y
s
to
ck
h
ar
d
w
ar
e
t
h
at
n
o
r
m
al
co
n
s
u
m
er
elec
tr
o
n
ic
s
w
o
u
ld
u
s
e.
3
.
2
.
Aco
us
t
ic
Cry
pta
na
ly
s
is
Sid
e
-
c
h
an
n
el
attac
k
s
ar
e
a
cl
ass
o
f
p
h
y
s
ical
attac
k
s
in
w
h
ich
an
attac
k
er
tr
ies
to
ex
p
lo
it
p
h
y
s
ica
l
in
f
o
r
m
atio
n
leak
a
g
es
f
r
o
m
t
h
o
s
e
d
ev
ice
s
.
Sid
e
-
c
h
a
n
n
el
attac
k
s
tar
g
et
i
m
p
le
m
en
tat
io
n
s
o
f
cr
y
p
to
g
r
ap
h
i
c
alg
o
r
ith
m
s
w
h
ic
h
ca
n
lea
k
s
ec
r
et
in
f
o
r
m
atio
n
t
h
r
o
u
g
h
i
n
d
ir
ec
t
ch
an
n
el
s
s
u
c
h
as
p
o
w
er
co
n
s
u
m
p
tio
n
,
elec
tr
o
m
ag
n
etic
e
m
an
a
tio
n
s
,
ti
m
i
n
g
v
ar
iatio
n
s
an
d
ac
o
u
s
tic
e
m
an
a
tio
n
s
[
5
1
]
–
[
5
4
]
.
A
co
u
s
tic
attac
k
is
a
t
y
p
e
o
f
s
i
d
e
-
ch
a
n
n
e
l
attac
k
s
w
h
ic
h
m
ai
n
l
y
b
ased
o
n
th
e
s
o
u
n
d
p
r
o
d
u
ce
d
b
y
th
e
d
ev
ices
esp
ec
iall
y
co
m
p
u
ter
p
er
ip
h
er
als
o
r
elec
tr
ical
co
m
p
o
n
en
t
s
i
n
s
id
e
co
m
p
u
ter
s
t
h
at
m
a
y
n
o
t
b
e
au
d
ib
le
to
h
u
m
a
n
.
A
co
u
s
tic
e
m
an
at
io
n
s
t
h
at
g
en
er
ated
b
y
co
m
p
u
ter
s
,
ar
e
o
n
e
s
u
c
h
p
o
ten
tial
c
h
an
n
el.
T
h
e
s
o
u
r
ce
o
f
attac
k
s
o
n
th
e
s
ec
u
r
it
y
o
f
co
m
p
u
ter
s
y
s
te
m
s
p
r
o
d
u
ce
d
b
y
e
m
an
a
tio
n
s
f
r
o
m
elec
tr
o
n
ic
d
ev
ices
h
av
e
lo
n
g
b
ee
n
in
v
e
s
ti
g
ated
a
m
o
n
g
r
esear
ch
er
s
[
1
2
]
,
[
5
3
]
,
[
5
5
]
–
[
5
7
]
.
T
h
is
attac
k
is
in
e
x
p
en
s
i
v
e
an
d
n
o
n
-
i
n
v
asi
v
e
b
ec
au
s
e
t
h
e
o
n
l
y
o
t
h
er
h
ar
d
w
ar
e
n
ee
d
ed
t
o
p
er
f
o
r
m
t
h
e
attac
k
s
is
a
p
ar
ab
o
lic
m
icr
o
p
h
o
n
e.
Me
c
h
an
i
ca
l
v
ib
r
atio
n
s
f
r
o
m
f
an
s
a
n
d
s
to
r
ag
e
d
ev
ice
s
s
u
ch
as
h
ar
d
d
is
k
s
d
u
r
i
n
g
s
y
s
te
m
ac
t
iv
i
t
y
in
d
u
ce
d
n
o
i
s
e
m
a
y
ca
r
r
y
v
al
u
ab
le
in
f
o
r
m
atio
n
t
h
at
i
s
ap
p
ar
en
tl
y
o
f
litt
le
u
s
e
f
o
r
cr
y
p
ta
n
al
y
s
i
s
.
P
h
y
s
ical
i
n
tr
u
s
io
n
i
n
to
th
e
s
y
s
te
m
i
s
also
n
o
t
r
eq
u
ir
ed
an
d
th
e
s
o
u
n
d
ca
n
b
e
r
ec
o
r
d
ed
f
r
o
m
a
s
u
b
s
ta
n
tia
l
d
is
tan
ce
.
I
t
is
cr
u
cial
f
o
r
p
u
b
lic
u
s
er
s
an
d
s
er
v
ice
p
r
o
v
id
er
s
to
s
ta
y
ab
r
ea
s
t o
f
th
e
p
r
o
g
r
ess
an
d
tr
en
d
s
o
n
cr
y
p
t
an
al
y
s
is
o
f
s
ec
u
r
it
y
p
r
o
to
co
l.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
d
o
n
esia
n
J
E
lec
E
n
g
&
C
o
m
p
Sci
I
SS
N:
2502
-
4752
Da
ta
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xfiltr
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493
I
n
an
o
t
h
er
p
er
s
p
ec
tiv
e,
r
ec
en
t
w
o
r
k
s
h
o
w
s
th
a
t
u
ltra
s
o
n
ic
s
i
g
n
al
h
a
s
e
m
a
n
ated
f
r
o
m
co
m
p
u
ter
s
t
h
at
e
m
it
a
h
ig
h
-
p
itch
ed
s
ig
n
al
d
u
r
in
g
o
p
er
atio
n
,
d
u
e
to
v
ib
r
ati
o
n
in
s
o
m
e
o
f
t
h
eir
elec
tr
o
n
i
c
co
m
p
o
n
e
n
t
s
[
5
8
]
.
Du
r
in
g
t
h
e
C
P
U
o
p
er
atio
n
,
t
h
e
p
o
w
er
co
n
s
u
m
p
t
io
n
s
f
l
u
ct
u
ate
to
s
u
p
p
l
y
th
e
co
n
s
ta
n
t
v
o
ltag
e
w
it
h
i
n
t
h
e
ch
ip
s
ets
co
m
p
o
n
e
n
ts
.
T
h
ese
ac
o
u
s
tic
e
m
a
n
atio
n
s
ca
n
e
x
p
o
s
e
an
d
lea
k
v
al
u
ab
le
i
n
f
o
r
m
at
io
n
r
eg
ar
d
i
n
g
s
ec
u
r
it
y
-
r
ela
ted
co
m
p
u
tatio
n
s
.
T
h
e
m
ai
n
i
s
s
u
e
w
a
s
t
h
e
v
er
y
lo
w
ac
o
u
s
tic
s
id
e
c
h
an
n
el
b
an
d
w
id
th
th
a
t
o
p
er
ates
u
n
d
er
2
0
k
Hz
u
s
in
g
co
m
m
o
n
m
icr
o
p
h
o
n
e
s
,
a
n
d
a
f
e
w
h
u
n
d
r
ed
k
Hz
u
s
in
g
u
ltra
s
o
u
n
d
m
icr
o
p
h
o
n
e
s
.
I
n
ter
esti
n
g
l
y
,
r
ec
en
t
s
t
u
d
ies
h
av
e
s
h
o
w
n
t
h
at
a
f
u
ll
4
0
9
6
-
b
it
R
S
A
k
e
y
en
cr
y
p
tio
n
ca
n
b
e
ex
tr
ac
ted
f
r
o
m
a
lap
to
p
c
o
m
p
u
ter
b
y
a
n
al
y
s
i
n
g
th
e
au
d
ib
le
s
o
u
n
d
s
i
g
n
al
d
u
r
i
n
g
o
p
er
atio
n
[
5
8
]
,
[
5
9
]
.
Data
en
cr
y
p
tio
n
s
ta
n
d
ar
d
R
S
A
a
m
o
n
g
th
e
ea
r
lies
t
p
r
ac
t
ical
p
u
b
lic
-
k
e
y
cr
y
p
to
s
y
s
te
m
s
th
at
is
w
id
el
y
u
s
ed
f
o
r
s
ec
u
r
e
d
ata
tr
an
s
m
i
s
s
io
n
.
T
h
e
ac
o
u
s
tic
at
tack
s
ar
e
ca
p
a
b
le
to
ex
tr
ac
t
t
h
e
p
u
b
lic
k
e
y
s
f
r
o
m
v
ar
io
u
s
v
er
s
io
n
s
o
f
co
m
p
u
ter
s
u
s
i
n
g
t
h
e
s
o
u
n
d
g
e
n
er
ated
d
u
r
i
n
g
t
h
e
d
ec
r
y
p
tio
n
o
f
s
o
m
e
c
h
o
s
en
cip
h
er
tex
ts
.
Fig
u
r
e
2
s
h
o
ws
t
h
e
o
v
er
v
ie
w
o
f
eq
u
ip
m
e
n
t
t
h
at
h
a
v
e
b
ee
n
u
s
e
d
in
th
e
e
x
p
er
i
m
e
n
t
[
5
8
]
,
[
5
9
]
.
T
h
r
ee
ex
p
er
im
e
n
tal
s
e
tu
p
s
h
a
v
e
b
ee
n
co
n
s
id
er
ed
r
ep
r
esen
tin
g
v
ar
io
u
s
tr
ad
e
-
o
f
f
s
b
et
w
ee
n
co
s
ts
,
p
o
r
tab
ilit
y
an
d
m
ea
s
u
r
i
n
g
ca
p
ab
ilit
ie
s
.
T
h
is
s
etu
p
ai
m
s
f
o
r
th
e
b
est
p
o
s
s
ib
le
ac
o
u
s
tic
ac
q
u
is
i
tio
n
q
u
alit
y
(
i
n
ter
m
s
o
f
s
e
n
s
itiv
it
y
,
s
i
g
n
al
a
n
d
f
r
eq
u
e
n
c
y
r
esp
o
n
s
e)
an
d
h
i
g
h
f
le
x
ib
ilit
y
in
m
ea
s
u
r
e
m
en
t c
o
n
f
i
g
u
r
atio
n
.
Fig
u
r
e
2
.
An
I
llu
s
tr
atio
n
o
f
A
c
o
u
s
tic
A
ttac
k
o
n
Mo
b
ile
C
o
m
p
u
ter
s
in
[
5
8
]
,
[
5
9
]
4.
CO
UNT
E
RM
E
ASURE
S AN
D
F
URTHER P
E
RSP
E
C
T
I
VE
S
An
o
b
v
io
u
s
id
ea
f
o
r
co
u
n
ter
m
ea
s
u
r
i
n
g
ac
o
u
s
tic
attac
k
s
i
s
s
ilen
t
m
icr
o
p
r
o
ce
s
s
o
r
s
,
w
h
i
ch
d
o
n
o
t
p
r
o
d
u
c
e
an
y
s
o
u
n
d
o
r
leak
ag
e
s
ig
n
al.
T
h
e
latest
v
er
s
io
n
o
f
C
P
U
f
o
r
ex
a
m
p
le
li
k
e
I
n
tel
i7
w
ith
q
u
ad
co
r
e
p
r
o
ce
s
s
o
r
s
an
d
ab
o
v
e
w
o
u
ld
p
r
o
d
u
ce
f
aster
p
r
o
ce
s
s
in
g
ti
m
e
an
d
lo
w
er
s
o
u
n
d
.
S
m
a
ller
s
ize
d
ev
ice
s
u
ch
as
tab
lets
an
d
m
o
b
ile
g
ad
g
et
s
wo
u
ld
also
p
r
ev
en
t
t
h
e
ac
o
u
s
t
ic
s
ig
n
als
f
r
o
m
tr
an
s
m
i
tted
ex
te
r
n
all
y
.
T
h
e
ab
o
v
e
-
m
en
tio
n
ed
w
a
y
s
ar
e
u
s
e
f
u
l
i
n
av
o
id
in
g
e
m
a
n
atio
n
o
f
s
o
u
n
d
f
r
o
m
p
r
o
ce
s
s
o
r
s
o
r
C
P
Us.
Oth
er
m
et
h
o
d
is
to
in
cr
ea
s
e
th
e
d
is
tan
ce
b
et
w
ee
n
th
e
d
ev
ices
an
d
t
h
e
m
icr
o
p
h
o
n
e
in
s
u
c
h
a
w
a
y
w
h
er
e
th
e
s
i
g
n
al
d
etec
tio
n
r
at
e
d
r
o
p
s
s
u
b
s
tan
t
iall
y
.
Alt
h
o
u
g
h
th
is
m
a
y
n
o
t
b
e
u
s
e
f
u
l
to
all
c
ases
as
m
icr
o
p
h
o
n
e
tech
n
o
lo
g
y
f
o
r
u
ltra
s
o
n
ic
h
a
s
d
ev
elo
p
ed
r
ap
id
ly
i
n
ter
m
o
f
d
is
ta
n
ce
d
etec
tio
n
.
I
n
tr
o
d
u
ce
s
o
m
e
o
b
s
tacle
s
b
et
w
e
en
t
h
e
d
ev
ice
an
d
m
icr
o
p
h
o
n
e
ca
n
al
s
o
p
r
ev
en
t
th
e
s
o
u
n
d
r
ea
ch
in
g
t
h
e
r
ec
o
r
d
in
g
d
ev
ice
(
m
icr
o
p
h
o
n
e)
.
A
v
o
id
in
g
co
n
tact
w
it
h
m
icr
o
p
h
o
n
e:
th
e
ab
s
en
ce
o
f
m
icr
o
p
h
o
n
es
n
ea
r
e
m
a
n
atio
n
d
ev
ice
i
s
also
s
u
f
f
icie
n
t
to
p
r
o
tect
p
r
iv
ac
y
.
Fo
r
ac
o
u
s
tic
attac
k
s
e
m
a
n
ated
f
r
o
m
o
th
er
co
m
p
o
n
e
n
t
s
u
c
h
as
k
e
y
b
o
ar
d
o
r
p
r
in
ter
s
,
also
r
e
q
u
ir
ed
a
s
i
len
t
a
n
d
f
aster
tec
h
n
o
lo
g
ies.
No
w
ad
a
y
s
,
th
e
u
s
a
g
e
o
f
v
ir
tu
a
l
tech
n
o
l
o
g
y
r
ep
lacin
g
p
h
y
s
ica
l
h
ar
d
war
e
m
a
y
al
s
o
a
m
o
n
g
r
o
b
u
s
t
an
d
s
tate
-
of
-
t
h
e
-
ar
t
s
o
lu
tio
n
s
.
Fo
r
ex
a
m
p
le,
v
ir
t
u
al
k
e
y
b
o
ar
d
s
h
a
v
e
ap
p
ea
r
ed
w
h
er
eb
y
t
h
e
y
ca
n
b
e
p
r
o
j
ec
ted
o
n
a
f
lat
s
u
r
f
ac
e
[
6
0
]
–
[
6
2
]
.
Sim
ilar
l
y
w
it
h
r
ec
en
t
p
r
o
j
ec
t
o
n
th
e
d
ev
elo
p
m
e
n
t
o
f
v
ir
tu
a
l
m
icr
o
p
h
o
n
e
u
s
i
n
g
u
ltra
s
o
n
ic
s
i
g
n
al
as
s
o
u
n
d
r
ec
eiv
er
alth
o
u
g
h
t
h
is
m
et
h
o
d
m
a
y
r
eq
u
ir
e
m
o
r
e
d
ev
ices
a
s
tr
an
s
ce
i
v
er
s
[
6
3
]
.
T
h
ese
ch
o
ices
ar
e
m
o
r
e
ex
p
en
s
i
v
e
t
h
an
t
h
e
s
ta
n
d
ar
d
d
ev
ices,
y
et
it
ca
n
a
v
o
id
v
al
u
ab
le
in
f
o
r
m
atio
n
f
r
o
m
leak
i
n
g
.
Fu
r
t
h
er
w
o
r
k
is
c
u
r
r
en
t
l
y
b
ein
g
d
o
n
e
to
d
etec
t
t
h
e
lea
k
ag
e
i
n
p
r
iv
ate
i
n
f
o
r
m
atio
n
ca
u
s
ed
b
y
elec
tr
o
n
ic
d
ev
ices
’
e
m
an
atio
n
s
.
T
h
e
ac
o
u
s
tic
e
m
a
n
atio
n
s
o
r
ig
in
a
ted
f
r
o
m
t
h
e
o
p
er
ated
m
ic
r
o
p
r
o
c
ess
o
r
s
in
s
id
e
C
P
U
o
f
th
e
attac
k
ed
d
ev
ices
h
as
b
ee
n
d
is
cu
s
s
ed
b
ased
o
n
co
m
p
u
ter
o
p
er
atio
n
al
r
u
n
n
i
n
g
w
i
th
R
S
A
e
n
cr
y
p
tio
n
p
r
o
to
co
l
[
5
8
]
,
[
5
9
]
.
T
h
e
asy
m
m
etr
ic
p
r
o
p
er
ties
o
f
u
s
i
n
g
t
w
o
d
i
f
f
er
en
t
k
e
y
s
m
a
k
e
s
th
e
R
S
A
b
ec
o
m
e
v
u
l
n
er
ab
le
as
t
h
e
cr
y
p
to
s
y
s
te
m
it
s
el
f
i
s
m
ai
n
l
y
b
ased
o
n
t
h
e
m
at
h
e
m
a
tica
l
p
r
o
b
le
m
o
f
i
n
teg
er
f
ac
to
r
izatio
n
.
A
E
S,
f
o
r
i
n
s
tan
ce
,
u
s
es
a
u
n
iq
u
e
k
e
y
ca
lc
u
lated
f
e
w
ti
m
es
b
ased
o
n
s
e
v
er
al
s
u
b
s
ti
tu
tio
n
s
a
n
d
li
n
ea
r
tr
an
s
f
o
r
m
atio
n
o
f
t
h
e
en
cr
y
p
t
io
n
k
e
y
.
A
E
S
alg
o
r
it
h
m
r
e
m
ain
s
t
h
e
p
r
ef
er
r
ed
en
cr
y
p
tio
n
s
tan
d
ar
d
f
o
r
h
i
g
h
s
ec
u
r
it
y
s
y
s
te
m
a
r
o
u
n
d
th
e
g
lo
b
e.
Mo
tiv
ated
b
y
t
h
e
s
ig
n
i
f
ica
n
t
f
i
n
d
in
g
o
n
th
e
s
i
g
n
al
l
ea
k
ag
e
f
r
o
m
R
S
A
en
cr
y
p
tio
n
,
t
h
i
s
cu
r
r
en
t
w
o
r
k
i
s
ai
m
ed
to
d
etec
t a
n
d
ch
ar
ac
te
r
izes sig
n
al
p
r
o
f
ile
s
f
r
o
m
th
e
e
m
an
a
ted
u
ltra
s
o
n
ic
s
ig
n
al
r
u
n
n
i
n
g
o
n
A
E
S
e
n
cr
y
p
tio
n
s
y
s
te
m
an
d
d
eter
m
in
e
a
n
y
c
o
r
r
elatio
n
w
i
th
r
e
s
p
ec
t
to
ac
o
u
s
tic
p
r
o
p
er
ties
.
Fig
u
r
e
3
s
h
o
w
s
t
h
e
eq
u
ip
m
e
n
t
u
s
ed
to
p
er
f
o
r
m
t
h
e
ex
p
er
i
m
e
n
t
u
s
in
g
m
o
b
ile
co
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.
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h
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a
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h
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y
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o
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CCS
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0
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1
,
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.
1
0
.
[3
]
J.
R.
M
ich
e
n
e
r,
“
De
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g
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in
st u
se
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.
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.
[4
]
Y.
Hu
,
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Ho
ss
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in
,
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.
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n
d
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.
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a
sire
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y
,
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Reg
istry
fo
r
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e
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n
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n
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tern
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0
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,
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p
.
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.
[5
]
M
.
G
u
ri,
A
.
Ka
c
h
lo
n
,
O.
Ha
ss
o
n
,
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.
Ke
d
m
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,
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Y.
M
irsk
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,
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S
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e
m
:
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ta
Exfil
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o
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,
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r.
,
p
p
.
8
4
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–
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6
4
,
2
0
1
5
.
[6
]
C.
J.
D’O
ra
z
io
,
K.
K.
R.
Ch
o
o
,
a
n
d
L
.
T
.
Ya
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g
,
“
Da
ta
E
x
f
il
tratio
n
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ro
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In
tern
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o
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in
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s
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s:
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s
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ter
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e
t
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s J
.
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3
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0
1
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.
[7
]
A
.
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.
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n
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ra
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.
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ra
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n
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N.
I.
o
f
T
.
K.
Ka
m
a
th
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u
ra
th
k
a
l,
“
W
a
ll
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u
rv
e
y
o
r
Ro
b
o
t
u
si
n
g
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irele
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t
w
o
rk
s,”
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S
In
ter
n
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ti
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l
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0
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.
[8
]
Q.
Do
,
B.
M
a
rti
n
i,
a
n
d
K.
K.
R.
C
h
o
o
,
“
Ex
f
il
tratin
g
d
a
ta f
ro
m
A
n
d
ro
id
d
e
v
ice
s,”
Co
mp
u
t.
S
e
c
u
r.,
v
o
l
.
4
8
,
p
p
.
7
4
–
9
1
,
2
0
1
5
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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d
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J
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&
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n
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.
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y
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rd
s:
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1
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d
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ro
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in
k
a
l,
a
n
d
C.
S
p
o
r
led
e
r,
“
Aco
u
stic
S
i
d
e
-
c
h
a
n
n
e
l
At
t
a
c
k
s
o
n
Prin
ter
s,”
in
P
r
o
c
e
e
d
in
g
s o
f
th
e
1
9
t
h
USE
NI
X
Co
n
f
e
re
n
c
e
o
n
S
e
c
u
rit
y
,
2
0
1
0
,
p
.
2
0
.
[1
3
]
G
.
Jo
y
P
e
rsia
l,
M
.
P
ra
b
h
u
,
a
n
d
R
.
S
h
a
n
m
u
g
a
lak
sh
m
i,
“
S
id
e
Ch
a
n
n
e
l
A
tt
a
c
k
-
S
u
rv
e
y
,
”
In
t.
J
.
Rec
e
n
t
T
re
n
d
s
E
lec
tr.
El
e
c
tro
n
.
,
v
o
l.
1
,
n
o
.
2
,
p
p
.
4
9
–
5
4
,
2
0
1
1
.
[1
4
]
E.
De
M
u
ld
e
r,
P
.
Bu
y
ss
c
h
a
e
rt,
S
.
B.
Ors
,
P
.
De
lm
o
tt
e
,
B.
P
re
n
e
e
l,
G
.
V
a
n
d
e
n
b
o
sc
h
,
a
n
d
I.
V
e
rb
a
u
w
h
e
d
e
,
“
El
e
c
tro
ma
g
n
e
ti
c
An
a
lys
is
At
t
a
c
k
o
n
a
n
FP
GA
Imp
lem
e
n
t
a
ti
o
n
o
f
a
n
El
li
p
t
ic
Cu
rv
e
Cry
p
to
sy
st
e
m,”
In
t.
C
o
n
f
.
Co
m
p
u
t.
a
s a
T
o
o
l
-
EUROCO
N’0
5
,
v
o
l.
2
,
p
p
.
1
8
7
9
–
1
8
8
2
,
2
0
0
5
.
[1
5
]
H.
Ba
r
-
El
,
“
W
h
it
e
p
a
p
e
r
o
n
I
n
tro
d
u
c
ti
o
n
to
S
i
d
e
Ch
a
n
n
e
l
A
tt
a
c
k
s,”
S
e
c
u
r.
In
teg
r.
Circu
it
s S
y
st.,
2
0
1
0
.
[1
6
]
W
.
Ch
e
n
,
G
.
P
.
Ha
n
c
k
e
,
K.
E.
M
a
y
e
s,
Y.
L
ien
,
a
n
d
J.
H.
Ch
iu
,
“
N
FC
mo
b
il
e
tra
n
sa
c
ti
o
n
s
a
n
d
a
u
t
h
e
n
ti
c
a
ti
o
n
b
a
se
d
o
n
GS
M
n
e
two
rk
,
”
i
n
P
r
o
c
e
e
d
in
g
s
-
2
n
d
In
tern
a
ti
o
n
a
l
W
o
rk
sh
o
p
o
n
Ne
a
r
F
ield
Co
m
m
u
n
ica
ti
o
n
,
NFC
2
0
1
0
,
2
0
1
0
,
p
p
.
8
3
–
8
9
.
[1
7
]
F
.
G
u
sta
f
ss
o
n
a
n
d
F
.
G
u
n
n
a
rss
o
n
,
“
M
o
b
il
e
p
o
siti
o
n
i
n
g
u
sin
g
w
irele
ss
n
e
t
w
o
rk
s:
P
o
ss
ib
il
i
ti
e
s
a
n
d
f
u
n
d
a
m
e
n
tal
li
m
it
a
ti
o
n
s
b
a
se
d
o
n
a
v
a
il
a
b
le
w
irele
ss
n
e
t
w
o
rk
m
e
a
su
re
m
e
n
ts,”
I
EE
E
S
i
g
n
a
l
Pro
c
e
ss
.
M
a
g
.
,
v
o
l.
2
2
,
n
o
.
4
,
p
p
.
4
1
–
5
3
,
2
0
0
5
.
[1
8
]
A
.
M
a
n
b
a
c
h
i
a
n
d
R.
S
.
C.
Co
b
b
o
ld
,
“
De
v
e
lo
p
m
e
n
t
a
n
d
a
p
p
li
c
a
ti
o
n
o
f
p
iez
o
e
lec
tri
c
m
a
teria
ls
f
o
r
u
lt
ra
so
u
n
d
g
e
n
e
ra
ti
o
n
a
n
d
d
e
tec
ti
o
n
,
”
Ultra
s
o
u
n
d
,
v
o
l.
1
9
,
n
o
.
4
,
p
p
.
1
8
7
–
1
9
6
,
2
0
1
1
.
[1
9
]
A
.
T
o
p
ra
k
a
n
d
O.
T
i
g
li
,
“
P
iez
o
e
l
e
c
tri
c
e
n
e
rg
y
h
a
r
v
e
stin
g
:
S
tate
-
of
-
th
e
-
a
rt
a
n
d
c
h
a
ll
e
n
g
e
s,”
A
p
p
l.
P
h
y
s.
R
e
v
.
,
v
o
l.
1
,
n
o
.
3
,
p
.
3
1
1
0
4
,
2
0
1
4
.
[2
0
]
A
.
A
.
V
iv
e
s,
P
iez
o
e
lec
tri
c
tran
sd
u
c
e
rs an
d
a
p
p
li
c
a
ti
o
n
s.
2
0
0
8
.
[2
1
]
H.
P
e
y
v
a
n
d
i,
M
.
F
a
rro
k
h
ro
o
z
,
H.
Ro
u
f
a
rsh
b
a
f
,
a
n
d
S
.
-
J.
P
a
rk
,
“
S
O
NAR
S
y
ste
ms
a
n
d
Un
d
e
rwa
ter
S
i
g
n
a
l
Pro
c
e
ss
in
g
:
Cla
ss
ic a
n
d
M
o
d
e
rn
A
p
p
ro
a
c
h
e
s,
”
in
S
o
n
a
r
S
y
ste
m
s,
2
0
1
1
,
p
p
.
1
7
3
–
2
0
6
.
[2
2
]
A
.
D.
(As
h
le
y
D
.
W
a
it
e
,
S
o
n
a
r
f
o
r
p
ra
c
ti
sin
g
e
n
g
in
e
e
rs,
n
o
.
3
.
2
0
1
6
.
[2
3
]
R.
P
.
T
h
o
m
a
s,
K.
K.
Jith
in
,
K.
S
.
Ha
re
e
sh
,
C.
A
.
H
a
b
e
e
b
u
ra
h
m
a
n
,
a
n
d
J.
A
b
ra
h
a
m
,
“
Ra
n
g
e
D
e
t
e
c
ti
o
n
b
a
se
d
o
n
Ultras
o
n
ic
P
ri
n
c
ip
le,”
I
n
t.
J
.
Ad
v
.
Res
.
El
e
c
tr.
El
e
c
tro
n
.
In
stru
m
.
En
g
.
,
v
o
l
.
3
,
n
o
.
2
,
p
p
.
7
6
3
8
–
7
6
4
2
,
2
0
1
4
.
[2
4
]
J.
-
H.
G
u
,
H.
-
G
.
Jo
e
,
a
n
d
S
.
C
.
Yu
,
“
De
v
e
lo
p
m
e
n
t
o
f
ima
g
e
so
n
a
r
si
m
u
lato
r
f
o
r
u
n
d
e
rw
a
ter
o
b
jec
t
re
c
o
g
n
it
io
n
,
”
2
0
1
3
Oc
e
a
n
.
-
S
a
n
Die
g
o
,
p
p
.
1
–
6
,
2
0
1
3
.
[2
5
]
M
.
S
.
M
u
ll
a
k
a
e
v
,
V
.
O.
A
b
ra
m
o
v
,
a
n
d
A
.
V
.
A
b
ra
m
o
v
a
,
“
D
e
v
e
lo
p
m
e
n
t
o
f
u
lt
ra
so
n
ic
e
q
u
i
p
m
e
n
t
a
n
d
tec
h
n
o
l
o
g
y
f
o
r
w
e
ll
sti
m
u
latio
n
a
n
d
e
n
h
a
n
c
e
d
o
il
re
c
o
v
e
r
y
,
”
J
.
Pet.
S
c
i.
En
g
.
,
v
o
l.
1
2
5
,
p
p
.
2
0
1
–
2
0
8
,
2
0
1
5
.
[2
6
]
F
.
F
e
u
c
h
t,
J.
Ke
tela
e
r,
A
.
W
o
lff
,
M
.
M
o
r
i,
a
n
d
M
.
F
u
ji
s
h
im
a
,
“
L
a
tes
t
ma
c
h
i
n
in
g
tec
h
n
o
lo
g
ies
o
f
h
a
rd
-
to
-
c
u
t
ma
ter
ia
ls b
y
u
lt
ra
s
o
n
ic m
a
c
h
i
n
e
t
o
o
l
,
”
i
n
P
r
o
c
e
d
ia CIR
P
,
2
0
1
4
,
v
o
l
.
1
4
,
p
p
.
1
4
8
–
1
5
2
.
[2
7
]
M
.
P
.
M
a
t
h
e
n
y
a
n
d
K.
F
.
G
ra
ff,
“
Ultras
o
n
ic
w
e
ld
in
g
o
f
m
e
tals,
”
in
P
o
w
e
r
Ultras
o
n
ics
:
A
p
p
li
c
a
ti
o
n
s
o
f
Hig
h
-
In
ten
sity
Ultras
o
u
n
d
,
2
0
1
4
,
p
p
.
2
5
9
–
2
9
3
.
[2
8
]
P
.
N.
T
.
W
e
ll
s
a
n
d
H.
-
D.
L
ian
g
,
“
M
e
d
ica
l
u
lt
ra
so
u
n
d
:
im
a
g
in
g
o
f
so
f
t
ti
ss
u
e
stra
in
a
n
d
e
las
ti
c
it
y
,
”
J.
R.
S
o
c
.
In
terf
a
c
e
,
v
o
l.
8
,
n
o
.
6
4
,
p
p
.
1
5
2
1
–
1
5
4
9
,
2
0
1
1
.
[2
9
]
M
.
P
o
ste
m
a
,
F
u
n
d
a
m
e
n
tals o
f
m
e
d
ica
l
u
lt
ra
so
n
ics
.
2
0
1
1
.
[3
0
]
S
.
J.
O’Malle
y
a
n
d
K.
-
K.
R.
Ch
o
o
,
“
Brid
g
i
n
g
th
e
a
ir
g
a
p
:
I
n
a
u
d
i
b
le
d
a
t
a
e
x
fi
lt
ra
ti
o
n
b
y
in
si
d
e
rs
,
”
20t
h
A
m
.
Co
n
f
.
In
f
.
S
y
st.
A
M
CIS
2
0
1
4
,
n
o
.
M
u
n
r
o
2
0
1
2
,
p
p
.
1
–
1
2
,
2
0
1
4
.
[3
1
]
M
.
A
rn
o
ld
,
“
A
u
d
i
o
W
a
ter
ma
rk
in
g
:
Fea
tu
re
s,
Ap
p
li
c
a
ti
o
n
s
a
n
d
Al
g
o
rit
h
ms
,
”
M
u
l
ti
m
e
d
.
Ex
p
o
,
2
0
0
0
.
IC
M
E
2
0
0
0
.
2
0
0
0
IE
EE
I
n
t.
C
o
n
f
.
(
V
o
l
u
m
e
2
),
v
o
l.
0
,
n
o
.
c
,
p
p
.
1
0
1
3
–
1
0
1
6
,
2
0
0
0
.
[3
2
]
R.
F
.
Ola
n
re
w
a
j
u
a
n
d
O.
Kh
a
li
fa
,
“
Dig
it
a
l
a
u
d
io
w
a
ter
ma
rk
in
g
;
tec
h
n
iq
u
e
s
a
n
d
a
p
p
li
c
a
ti
o
n
s,
”
2
0
1
2
In
t
.
Co
n
f
.
Co
m
p
u
t.
Co
m
m
u
n
.
En
g
.
,
n
o
.
J
u
ly
,
p
p
.
8
3
0
–
8
3
5
,
2
0
1
2
.
[3
3
]
H.
Ka
u
r,
“
Bli
n
d
A
u
d
io
W
a
ter
m
a
r
k
in
g
sc
h
e
m
e
s :
A
L
it
e
ra
tu
re
Re
v
iew
,
”
IRA
CS
T
–
En
g
.
S
c
i.
T
e
c
h
n
o
l
.
An
In
t.
J
.
,
v
o
l.
3
,
n
o
.
2
,
p
p
.
2
8
8
–
2
9
5
,
2
0
1
3
.
[3
4
]
H.
M
a
tsu
o
k
a
,
Y.
Na
k
a
sh
ima
,
a
n
d
T
.
Yo
sh
im
u
ra
,
“
A
c
o
u
stic
C
o
m
m
u
n
ica
ti
o
n
S
y
ste
m
Us
in
g
M
o
b
i
le
T
e
r
m
in
a
l
M
icro
p
h
o
n
e
s,”
NT
T
D
o
Co
M
o
T
e
c
h
.
J
.
,
v
o
l
.
8
,
n
o
.
2
,
p
p
.
4
–
1
2
,
2
0
0
4
.
[3
5
]
M
.
M
.
S
a
a
d
,
C.
J.
Blea
k
le
y
,
a
n
d
S
.
Do
b
so
n
,
“
Ro
b
u
st
h
ig
h
-
a
c
c
u
ra
c
y
u
lt
ra
so
n
ic
ra
n
g
e
m
e
a
su
re
m
e
n
t
s
y
ste
m
,
”
in
I
EE
E
T
ra
n
sa
c
ti
o
n
s
o
n
In
str
u
me
n
ta
t
io
n
a
n
d
M
e
a
su
re
me
n
t
,
2
0
1
1
,
v
o
l.
6
0
,
n
o
.
1
0
,
p
p
.
3
3
3
4
–
3
3
4
1
.
[3
6
]
D.
N.
I.
o
f
I.
T
.
Ju
a
n
,
Z.
N.
I.
o
f
I.
T
.
Zh
ih
o
n
g
,
a
n
d
Y.
N.
I.
o
f
I.
T
.
M
in
g
li
a
n
,
“
Ultras
o
n
ic
A
u
to
m
a
ti
c
T
ra
c
k
in
g
S
y
st
e
m
,
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EL
KOM
NIKA
(
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e
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o
mm
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n
ica
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n
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mp
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ti
n
g
,
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e
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tro
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n
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1
2
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o
.
6
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p
p
.
4
6
6
4
–
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6
7
0
,
2
0
1
4
.
[3
7
]
R.
Dia
z
-
M
o
ra
les
,
“
Cro
ss
-
De
v
ic
e
T
ra
c
k
in
g
:
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a
tch
in
g
De
v
ice
s
a
n
d
Co
o
k
ies
,
”
in
P
ro
c
e
e
d
in
g
s
-
1
5
th
IEE
E
In
tern
a
ti
o
n
a
l
C
o
n
f
e
re
n
c
e
o
n
Da
ta
M
in
i
n
g
W
o
rk
sh
o
p
,
ICD
M
W
2
0
1
5
,
2
0
1
6
,
p
p
.
1
6
9
9
–
1
7
0
4
.
[3
8
]
D.
A
rp
,
E.
Qu
iri
n
g
,
C.
W
re
ss
n
e
g
g
e
r,
a
n
d
K.
Riec
k
,
“
Priva
c
y
T
h
re
a
ts
th
ro
u
g
h
Ultra
so
n
ic
S
i
d
e
Ch
a
n
n
e
ls
o
n
M
o
b
il
e
De
v
ice
s,”
P
ro
c
.
I
EE
E
E
u
r.
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y
m
p
.
S
e
c
u
r.
P
riv
.
,
2
0
1
7
.
[3
9
]
J.
Bro
o
k
m
a
n
,
P
.
R
o
u
g
e
,
A
.
A
l
v
a
,
a
n
d
C.
Ye
u
n
g
,
“
Cro
ss
-
De
v
ice
T
ra
c
k
in
g
:
M
e
a
su
re
me
n
t
a
n
d
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lo
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re
s,
”
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r
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c
.
P
riv
.
En
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n
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T
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0
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o
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2
,
p
p
.
1
1
3
–
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2
8
,
2
0
1
7
.
[4
0
]
S
.
Ca
b
u
k
,
C.
E.
Bro
d
ley
,
a
n
d
C.
S
h
ield
s,
“
I
P
Co
v
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rt
Ch
a
n
n
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l
De
t
e
c
ti
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n
,
”
ACM
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ra
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In
f.
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r.,
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o
l.
1
2
,
n
o
.
4
,
p
p
.
1
–
2
9
,
2
0
0
9
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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:
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.
2
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2
0
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8
:
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9
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9
7
496
[4
1
]
S
.
Ch
a
n
d
ra
,
Z.
L
in
,
A
.
Ku
n
d
u
,
a
n
d
L
.
Kh
a
n
,
“
T
o
w
a
rd
s
a
s
y
s
tem
a
ti
c
stu
d
y
o
f
th
e
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o
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rt
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h
a
n
n
e
l
a
tt
a
c
k
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in
s
m
a
rtp
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o
n
e
s,”
in
L
e
c
tu
re
No
tes
o
f
th
e
In
stit
u
te
f
o
r
Co
m
p
u
ter
S
c
ien
c
e
s,
S
o
c
ial
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In
f
o
rm
a
ti
c
s
a
n
d
Tele
c
o
m
m
u
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ica
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n
s
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g
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NICST
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l.
1
5
2
,
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0
1
5
,
p
p
.
4
2
7
–
4
3
5
.
[4
2
]
S
.
A
.
A
h
m
a
d
z
a
d
e
h
a
n
d
G
.
Ag
n
e
w
,
“
T
u
rb
o
c
o
v
e
rt
c
h
a
n
n
e
l:
An
it
e
ra
ti
v
e
fra
me
wo
rk
fo
r
c
o
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e
rt
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o
mm
u
n
ica
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o
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o
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d
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t
a
n
e
tw
o
rk
s,”
i
n
P
r
o
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d
in
g
s
-
IEE
E
INFOCOM,
2
0
1
3
,
p
p
.
2
0
3
1
–
2
0
3
9
.
[4
3
]
M
.
Vu
a
g
n
o
u
x
a
n
d
S
.
P
a
sin
i,
“
A
n
imp
ro
v
e
d
tec
h
n
iq
u
e
to
d
isc
o
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e
r
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o
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ro
misin
g
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tro
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g
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ma
n
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ti
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s,
”
in
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In
tern
a
ti
o
n
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l
S
y
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o
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g
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Co
m
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a
ti
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il
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y
,
2
0
1
0
,
p
p
.
1
2
1
–
1
2
6
.
[4
4
]
M
.
G
.
Ku
h
n
,
“
Co
m
p
ro
m
isin
g
e
m
a
n
a
ti
o
n
s
o
f
L
CD
T
V
se
ts,”
IEE
E
T
ra
n
s.
El
e
c
tro
m
a
g
n
.
Co
mp
a
t.
,
v
o
l.
5
5
,
n
o
.
3
,
p
p
.
564
–
5
7
0
,
2
0
1
3
.
[4
5
]
B.
Ca
rra
ra
a
n
d
C.
A
d
a
m
s,
“
On
a
c
o
u
stic
c
o
v
e
rt
c
h
a
n
n
e
ls
b
e
t
w
e
e
n
a
ir
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g
a
p
p
e
d
s
y
ste
m
s,”
L
e
c
t.
No
tes
Co
m
p
u
t.
S
c
i.
(in
c
lu
d
in
g
S
u
b
se
r.
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e
c
t.
No
tes
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rti
f
.
In
tell.
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e
c
t.
No
tes
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i
n
f
o
rm
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ti
c
s),
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o
l.
8
9
3
0
,
p
p
.
3
–
1
6
,
2
0
1
5
.
[4
6
]
M
.
Ha
n
sp
a
c
h
a
n
d
M
.
G
o
e
tz,
“
On
c
o
v
e
rt
a
c
o
u
stica
l
m
e
sh
n
e
tw
o
rk
s
in
a
ir
,
”
J
.
C
o
mm
u
n
.
,
v
o
l
.
8
,
n
o
.
1
1
,
p
p
.
7
5
8
–
7
6
7
,
2
0
1
3
.
[4
7
]
A
.
M
a
d
h
a
v
a
p
e
d
d
y
,
D.
S
c
o
tt
,
A
.
T
se
,
a
n
d
R.
S
h
a
rp
,
“
A
u
d
io
n
e
two
rk
in
g
:
T
h
e
f
o
rg
o
tt
e
n
w
irele
s
s
te
c
h
n
o
l
o
g
y
,
”
IEE
E
Per
v
a
siv
e
Co
mp
u
ti
n
g
,
v
o
l.
4
,
n
o
.
3
.
p
p
.
5
5
–
6
0
,
2
0
0
5
.
[4
8
]
P
.
Ho
r
n
y
a
c
k
,
S
.
Ha
n
,
J.
Ju
n
g
,
S
.
S
c
h
e
c
h
ter,
a
n
d
D.
W
e
th
e
ra
ll
,
“
T
h
e
se
A
re
n
’t
th
e
Dro
id
s
Yo
u
’re
L
o
o
k
in
g
f
o
r:
Re
tro
f
it
ti
n
g
A
n
d
ro
id
to
P
ro
tec
t
D
a
ta f
ro
m
I
m
p
e
rio
u
s A
p
p
li
c
a
ti
o
n
s,
”
CCS
,
p
p
.
6
3
9
–
6
5
2
,
2
0
1
1
.
[4
9
]
A
.
K.
S
o
o
d
,
R.
En
b
o
d
y
,
A
.
K.
S
o
o
d
,
a
n
d
R.
En
b
o
d
y
,
“
Ch
a
p
ter
5
–
Da
ta
Ex
f
il
tratio
n
M
e
c
h
a
n
is
m
s,”
in
T
a
rg
e
ted
C
y
b
e
r
A
tt
a
c
k
s,
2
0
1
4
,
p
p
.
7
7
–
9
3
.
[5
0
]
T
.
Ho
s
m
a
n
,
M
.
Ye
a
ry
,
J.
K.
A
n
to
n
io
,
a
n
d
B
.
Ho
b
b
s,
“
M
u
lt
i
-
t
o
n
e
F
S
K
fo
r u
lt
ra
s
o
n
ic
c
o
mm
u
n
ic
a
ti
o
n
,
”
in
2
0
1
0
I
EE
E
In
tern
a
ti
o
n
a
l
In
stru
m
e
n
tatio
n
a
n
d
M
e
a
s
u
re
m
e
n
t
Tec
h
n
o
lo
g
y
Co
n
f
e
re
n
c
e
,
I2
M
T
C
2
0
1
0
-
P
r
o
c
e
e
d
in
g
s,
2
0
1
0
,
p
p
.
1
4
2
4
–
1
4
2
9
.
[5
1
]
Y.
Zh
o
u
a
n
d
D.
F
e
n
g
,
“
S
id
e
-
c
h
a
n
n
e
l
a
tt
a
c
k
s:
T
e
n
y
e
a
rs
a
ft
e
r
it
s
p
u
b
li
c
a
ti
o
n
a
n
d
t
h
e
imp
a
c
ts
o
n
c
ry
p
to
g
ra
p
h
ic
mo
d
u
le se
c
u
rity tes
ti
n
g
,
”
I
n
f
.
S
e
c
u
r.
S
e
m
in
.
W
S
0
6
0
7
,
n
o
.
6
0
5
0
3
0
1
4
,
p
p
.
1
–
3
4
,
2
0
0
5
.
[5
2
]
N.
L
a
w
so
n
,
“
S
id
e
-
c
h
a
n
n
e
l
a
tt
a
c
k
s o
n
c
ry
p
to
g
ra
p
h
ic s
o
f
twa
re
,
”
IEE
E
S
e
c
u
r.
Priv
.
,
v
o
l.
7
,
n
o
.
6
,
p
p
.
6
5
–
6
8
,
2
0
0
9
.
[5
3
]
B.
S
e
v
a
k
,
“
S
e
c
u
rit
y
a
g
a
in
st
S
id
e
Ch
a
n
n
e
l
A
tt
a
c
k
in
Clo
u
d
Co
m
p
u
t
in
g
,
”
In
t.
J
.
En
g
.
Ad
v
.
T
e
c
h
n
o
l.
,
v
o
l.
2
,
n
o
.
2
,
p
p
.
183
–
1
8
6
,
2
0
1
2
.
[5
4
]
D.
G
e
n
k
in
,
L
.
P
a
c
h
m
a
n
o
v
,
I.
P
i
p
m
a
n
,
a
n
d
E.
T
ro
m
e
r,
“
ECDH
k
e
y
-
e
x
trac
ti
o
n
v
ia
lo
w
-
b
a
n
d
w
id
th
e
lec
tro
m
a
g
n
e
ti
c
a
tt
a
c
k
s
o
n
P
Cs,”
i
n
L
e
c
tu
re
No
te
s
in
Co
m
p
u
ter
S
c
ien
c
e
(i
n
c
lu
d
in
g
su
b
se
ries
L
e
c
tu
re
No
tes
in
A
rti
f
i
c
ial
In
telli
g
e
n
c
e
a
n
d
L
e
c
tu
re
No
tes
in
Bi
o
i
n
f
o
rm
a
t
ics
),
2
0
1
6
,
v
o
l.
9
6
1
0
,
p
p
.
2
1
9
–
2
3
5
.
[5
5
]
G
.
M
.
De
e
p
a
,
G
.
S
rit
e
ja,
a
n
d
S
.
V
e
n
k
a
tes
wa
rlu
,
“
A
n
Ov
e
r
v
ie
w
o
f
A
c
o
u
stic
S
id
e
-
Ch
a
n
n
e
l
A
tt
a
c
k
,
”
v
o
l.
3
,
n
o
.
1
,
p
p
.
15
–
2
0
,
2
0
1
2
.
[5
6
]
C.
S
o
n
g
,
F
.
L
in
,
Z.
Ba
,
K
.
Re
n
,
C.
Zh
o
u
,
a
n
d
W
.
X
u
,
“
M
y
S
ma
rt
p
h
o
n
e
Kn
o
ws
W
h
a
t
Y
o
u
Prin
t :
Exp
lo
ri
n
g
S
ma
rtp
h
o
n
e
-
b
a
se
d
S
i
d
e
-
c
h
a
n
n
e
l
At
ta
c
k
s A
g
a
in
st
3
D P
ri
n
ter
s,”
i
n
A
CM
CCS
,
2
0
1
6
,
p
p
.
8
9
5
–
9
0
7
.
[5
7
]
D.
G
e
n
k
in
,
I.
P
ip
m
a
n
,
a
n
d
E.
T
r
o
m
e
r,
“
G
e
t
y
o
u
r
h
a
n
d
s
o
ff
m
y
la
p
to
p
:
p
h
y
sic
a
l
sid
e
-
c
h
a
n
n
e
l
k
e
y
-
e
x
trac
ti
o
n
a
tt
a
c
k
s
o
n
P
Cs:
Ex
ten
d
e
d
v
e
rsio
n
,
”
J
.
Cr
y
p
to
g
r.
En
g
.
,
v
o
l.
5
,
n
o
.
2
,
p
p
.
9
5
–
1
1
2
,
2
0
1
5
.
[5
8
]
D.
G
e
n
k
in
,
A
.
S
h
a
m
ir,
a
n
d
E.
T
ro
m
e
r,
“
A
c
o
u
stic Cry
p
tan
a
l
y
sis,”
J
.
Cry
p
to
l.
,
v
o
l.
3
0
,
n
o
.
2
,
p
p
.
3
9
2
–
4
4
3
,
2
0
1
7
.
[5
9
]
D.
G
e
n
k
in
,
A
.
S
h
a
m
ir,
a
n
d
E.
T
r
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r,
“
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k
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w
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b
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in
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tu
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No
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e
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telli
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6
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NCS,
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[6
0
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S
.
Zh
a
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M
.
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u
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ter,
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it
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Op
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p
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2
2
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9
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.
[6
1
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N.
He
n
z
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,
E.
Ru
k
z
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a
n
d
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.
Bo
ll
,
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Ob
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A
CM
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u
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m
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a
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-
C
HI
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2
,
p
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2
6
5
9
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2
0
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.
[6
2
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T
.
M
e
rk
e
l,
“
V
irt
u
a
l
M
icro
p
h
o
n
e
s :
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o
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h
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a
l
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in
A
I
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D
AG
A,
2
0
1
3
,
n
o
.
1
,
p
p
.
8
9
4
–
8
9
6
.
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e
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ik
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l
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T
e
M
).
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h
e
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in
s
t
h
e
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lt
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g
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m
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la
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in
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p
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n
d
h
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d
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ra
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ies
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f
o
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o
y
e
a
rs.
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n
a
tu
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a
p
ro
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in
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rd
o
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f
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a
s
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x
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tec
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p
a
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t
n
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trem
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r
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rre
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t
re
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h
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s a
re
o
n
a
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stics
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n
d
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ise
c
o
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tr
o
l.
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h
m
a
d
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a
iza
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o
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d
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s
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e
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ter
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t
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a
c
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lt
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f
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e
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e
c
h
n
o
lo
g
y
,
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iv
e
rsiti
S
a
in
s
Isla
m
M
a
la
y
sia
(USIM
).
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o
b
tai
n
e
d
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h
D
f
ro
m
th
e
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e
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n
sy
lv
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tat
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rsity
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A
p
re
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e
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e
d
b
y
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r
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c
h
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lo
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m
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o
f
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h
a
ff
ield
,
UK
.
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p
ro
f
e
ss
io
n
a
l
a
c
ti
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it
ies
in
c
lu
d
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d
m
e
m
b
e
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ip
o
f
th
e
In
stit
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te
o
f
En
g
in
e
e
rs
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lay
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(IE
M
)
a
s
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e
ll
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w
,
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m
b
a
g
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tera
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a
s
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ro
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En
g
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e
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tri
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ics
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g
in
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s
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io
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e
m
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r,
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a
d
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i
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in
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lay
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s
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ir
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n
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g
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g
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ip
li
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e
a
n
d
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o
w
&
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u
n
c
il
M
e
m
b
e
r
a
n
d
a
lso
In
stit
u
te
o
f
M
a
teria
ls
M
a
la
y
sia
a
s
F
e
ll
o
w
.
W
h
il
e
in
USIM
,
h
e
b
e
c
a
m
e
a
n
In
tern
a
l
a
n
d
Ex
tern
a
l
su
p
e
rv
iso
r
f
o
r
m
o
re
th
a
n
1
3
P
h
D
stu
d
e
n
ts.
He
p
u
b
li
s
h
e
d
m
o
re
th
a
n
1
6
b
o
o
k
s,
c
h
a
p
ter
in
b
o
o
k
s,
jo
u
r
n
a
ls
a
n
d
p
ro
c
e
e
d
in
g
sin
c
e
2
0
0
9
.
His
a
re
a
s
o
f
sp
e
c
ializa
ti
o
n
a
n
d
re
se
a
rc
h
in
tere
sts
in
c
lu
d
e
A
e
ro
n
o
m
y
,
Ae
ro
sp
a
c
e
S
c
ien
c
e
,
A
p
p
li
e
d
S
c
ien
c
e
s
&
T
e
c
h
n
o
l
o
g
ies
,
El
e
c
tro
m
a
g
n
e
ti
c
Co
m
p
a
ti
b
il
it
y
(EM
C)
a
n
d
W
irele
ss
Co
m
m
u
n
ica
ti
o
n
&
T
e
c
h
n
o
lo
g
i
e
s.
A
b
u
Ba
k
a
r
b
in
Ha
sa
n
re
c
e
iv
e
d
Ba
c
h
e
lo
r
d
e
g
re
e
in
P
h
y
sic
s
f
ro
m
Un
iv
e
rsiti
Ke
b
a
n
g
sa
a
n
M
a
la
y
sia
,
in
1
9
8
0
a
n
d
M
a
ste
rs
i
n
Dig
it
a
l
S
y
st
e
m
f
ro
m
Un
iv
e
rsit
y
o
f
Cra
n
f
ield
,
Un
it
e
d
Kin
g
d
o
m
in
1
9
8
4
.
H
e
p
u
rsu
e
d
h
is
P
h
.
D.
i
n
En
g
in
e
e
rin
g
a
t
Un
iv
e
rsiti
T
e
n
a
g
a
Na
sio
n
a
l
(UN
IT
EN)
in
2
0
1
3
a
f
ter
r
e
c
e
i
v
e
d
h
is
se
c
o
n
d
Ba
c
h
e
l
o
r
d
e
g
re
e
in
El
e
c
tri
c
a
l
En
g
in
e
e
rin
g
f
ro
m
Un
iv
e
rsiti
T
e
k
n
o
lo
g
i
M
a
la
y
sia
(U
T
M
)
in
2
0
1
0
.
He
jo
i
n
e
d
th
e
F
a
c
u
lt
y
o
f
En
g
in
e
e
rin
g
&
Bu
il
t
En
v
iro
n
m
e
n
t
,
Un
iv
e
rsiti
S
a
in
s
Isla
m
M
a
la
y
sia
(USIM
)
a
s
S
e
n
io
r
F
e
ll
o
w
a
n
d
c
u
rre
n
tl
y
a
p
p
o
in
te
d
a
s
De
p
u
t
y
De
a
n
o
f
F
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