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Vo
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6
,
No
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6
,
Dec
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201
6
,
p
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.
29
3
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8
I
SS
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2088
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8708
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DOI
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
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N
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2
0
8
8
-
8708
I
J
E
C
E
Vo
l.
6
,
No
.
6
,
Dec
em
b
er
201
6
:
29
3
9
–
29
4
8
2940
to
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m
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c
h
a
s
f
a
m
i
l
y
m
e
m
b
er
s
‟
n
a
m
es,
p
ets
‟
n
a
m
e
s
,
an
d
b
ir
th
d
a
y
s
[
1
2
-
1
5
]
.
A
u
s
e
f
u
l
alter
n
a
tiv
e
th
at
h
a
s
b
ee
n
p
r
o
p
o
s
ed
is
th
e
g
r
ap
h
ical
p
ass
w
o
r
d
tech
n
iq
u
e.
T
h
e
g
r
ap
h
ical
p
ass
w
o
r
d
is
p
o
s
s
ib
l
y
ea
s
ier
to
r
em
e
m
b
e
r
an
d
m
o
r
e
s
ec
u
r
e
co
m
p
ar
ed
to
tr
ad
itio
n
al
alp
h
a
n
u
m
er
ic
p
ass
w
o
r
d
as
t
h
e
y
m
a
k
e
u
s
e
o
f
h
u
m
a
n
s
‟
ca
p
ab
ilit
y
o
f
m
e
m
o
r
izin
g
an
d
r
ec
allin
g
i
m
a
g
es b
etter
.
Th
is
ap
p
r
o
ac
h
w
as
d
ev
elo
p
ed
to
s
o
lv
e
t
h
e
p
r
o
b
le
m
s
a
s
s
o
ciate
d
w
it
h
t
h
e
co
n
v
e
n
tio
n
a
l
p
ass
w
o
r
d
u
s
i
n
g
alp
h
a
n
u
m
er
ic
s
ch
e
m
e
s
.
T
h
is
ap
p
r
o
ac
h
also
m
a
k
es
i
t
ea
s
ier
to
m
e
m
o
r
ize
t
h
e
p
ass
wo
r
d
,
s
im
p
ler
to
u
s
e
an
d
h
a
s
m
o
r
e
s
ec
u
r
it
y
.
Gi
v
e
n
th
e
t
w
o
as
s
u
m
p
tio
n
s
th
a
t
h
u
m
an
s
c
a
n
r
ec
all
i
m
ag
e
s
b
etter
th
a
n
n
u
m
b
er
s
an
d
w
o
r
d
s
a
n
d
th
e
n
o
tio
n
t
h
at
a
p
ictu
r
e
i
s
m
o
r
e
v
al
u
ab
le
t
h
an
a
th
o
u
s
a
n
d
„
p
as
s
w
o
r
d
s
‟
,
s
o
f
t
war
e
co
m
p
a
n
ies
an
d
p
s
y
ch
o
lo
g
ical
r
esear
c
h
es
ap
p
ea
r
to
co
n
cu
r
w
it
h
t
h
is
ap
p
r
o
ac
h
[
1
6
-
1
8
]
.
Sear
ch
m
etr
ic
o
r
C
o
g
n
o
m
etr
ic
s
y
s
te
m
s
,
als
o
ca
lled
R
ec
o
g
n
itio
n
-
B
ase
d
s
y
s
te
m
s
,
r
eq
u
est
u
s
er
s
to
le
ar
n
a
n
d
r
ec
all
i
m
a
g
e
p
o
r
tf
o
li
o
s
d
u
r
i
n
g
p
ass
w
o
r
d
g
en
er
atio
n
,
an
d
n
e
x
t
i
n
o
r
d
er
to
lo
g
i
n
,
id
en
t
if
y
p
ict
u
r
es
a
m
o
n
g
t
h
e
d
ec
o
y
s
.
I
n
o
th
er
w
o
r
d
s
,
a
u
s
er
is
g
iv
e
n
a
g
r
o
u
p
o
f
i
m
ag
e
s
in
t
h
e
R
ec
o
g
n
i
tio
n
-
B
ased
t
ec
h
n
iq
u
e
a
n
d
au
th
e
n
tica
tio
n
i
s
ac
h
ie
v
ed
b
y
r
em
e
m
b
er
i
n
g
a
n
d
id
en
ti
f
y
i
n
g
th
e
s
elec
ted
i
m
a
g
e
at
th
e
in
it
ial
s
ta
g
e
o
f
r
eg
is
tr
atio
n
v
ar
io
u
s
i
m
a
g
e
t
y
p
es
ar
e
u
s
ed
b
y
th
e
s
u
g
g
e
s
ted
R
ec
o
g
n
it
io
n
-
B
ased
s
y
s
te
m
s
,
in
c
lu
d
i
n
g
ico
n
s
,
r
an
d
o
m
ar
t,
f
ac
es a
n
d
ev
er
y
d
a
y
o
b
j
ec
ts
.
Ho
w
e
v
er
,
s
in
ce
t
h
er
e
is
n
o
t
y
e
t
w
id
e
d
ep
lo
y
m
e
n
t
o
f
R
ec
o
g
n
i
tio
n
-
B
ased
g
r
ap
h
ical
p
ass
w
o
r
d
s
y
s
te
m
s
,
th
e
v
u
l
n
er
ab
ilit
ie
s
o
f
t
h
i
s
s
c
h
e
m
e
s
ar
e
s
t
ill
n
o
t
f
u
ll
y
u
n
d
er
s
to
o
d
.
Ov
er
all,
th
e
c
u
r
r
en
t
R
ec
o
g
n
itio
n
-
B
ased
g
r
ap
h
ical
p
ass
w
o
r
d
tech
n
iq
u
e
s
ar
e
s
till
i
m
m
atu
r
e.
Mu
c
h
m
o
r
e
r
esear
ch
an
d
u
s
er
s
tu
d
ies
ar
e
n
ee
d
ed
f
o
r
th
is
tech
n
iq
u
es
to
ac
h
ie
v
e
h
i
g
h
er
l
ev
els
o
f
m
atu
r
it
y
an
d
u
s
ef
u
l
n
ess
.
T
h
is
s
tu
d
y
co
m
p
r
is
e
s
o
f
a
co
m
p
lete
r
esear
ch
in
t
h
e
cu
r
r
en
t
R
ec
o
g
n
it
io
n
-
B
ased
g
r
ap
h
ical
p
as
s
w
o
r
d
s
c
h
e
m
e
an
d
r
ev
ie
w
t
h
eir
s
tr
e
n
g
t
h
s
a
n
d
w
ea
k
n
es
s
es.
T
h
e
co
m
m
o
n
u
s
ab
ilit
y
attr
ib
u
te
s
a
n
d
p
o
s
s
ib
le
a
ttack
s
o
n
t
h
e
R
e
co
g
n
itio
n
-
B
ased
g
r
ap
h
ical
p
as
s
w
o
r
d
i
s
r
e
v
ie
w
ed
,
id
en
ti
f
ied
,
an
d
ex
a
m
i
n
ed
in
d
etail.
I
n
ad
d
itio
n
,
w
e
h
av
e
co
n
d
u
cted
a
co
m
p
r
eh
e
n
s
i
v
e
an
d
co
m
p
ar
at
iv
e
s
t
u
d
y
o
f
ex
is
t
in
g
R
ec
o
g
n
it
io
n
-
B
ased
g
r
ap
h
ical
p
ass
w
o
r
d
tech
n
iq
u
es
f
r
o
m
th
e
p
o
in
t
v
ie
w
o
f
u
s
ab
ilit
y
f
ea
t
u
r
es,
lo
g
i
n
ti
m
e
a
n
d
lo
g
in
s
u
cc
e
s
s
r
ate
w
h
ich
ar
e
m
i
s
s
ed
in
p
r
ev
io
u
s
r
ela
ted
w
o
r
k
s
.
2.
SUM
M
ARY
O
F
T
H
E
P
RE
S
E
NT
R
E
CO
G
NI
T
I
O
N
-
B
ASE
D
G
RAP
H
I
CA
L
P
ASSWOR
D
SCH
E
M
E
S
2
.
1
.
P
a
s
s
f
a
ce
Sche
m
e
I
n
2
0
0
0
[
1
9
]
,
th
e
R
ea
l
User
C
o
r
p
o
r
atio
n
d
ev
elo
p
ed
a
tech
n
iq
u
e
ca
lled
t
h
e
P
ass
f
ac
e
s
ch
e
m
e.
T
h
e
R
ea
l
User
C
o
r
p
o
r
atio
n
u
s
i
n
g
t
h
e
as
s
u
m
p
tio
n
th
at
h
u
m
an
s
r
ec
all
f
ac
es
b
etter
th
a
n
an
y
o
t
h
e
r
i
m
ag
e
s
d
esi
g
n
ed
a
co
m
m
er
cial
p
r
o
d
u
ct
ca
l
led
th
e
P
ass
f
ac
e
s
.
W
ith
P
ass
f
ac
e
s
,
b
asicall
y
u
s
er
s
h
a
v
e
to
c
h
o
o
s
e
h
u
m
a
n
f
ac
e
t
h
e
y
h
av
e
s
ee
n
b
ef
o
r
e
f
r
o
m
a
ch
o
i
ce
o
f
n
in
e
f
ac
e
s
;
o
n
l
y
o
n
e
f
ac
e
is
k
n
o
w
n
to
th
e
m
,
th
e
r
est
a
ct
as
a
d
ec
o
y
.
T
h
is
s
tag
e
i
s
r
ep
ea
ted
co
n
tin
u
o
u
s
l
y
r
ep
ea
ted
till
th
e
y
ar
e
ab
le
id
en
ti
f
y
a
ll
f
o
u
r
f
ac
e
s
.
A
co
m
p
ar
ativ
e
r
esear
c
h
th
a
t
w
a
s
ca
r
r
ied
o
u
t
o
n
P
ass
f
ac
es
p
ass
w
o
r
d
f
o
u
n
d
th
at
i
t
w
as
ea
s
ier
r
ec
all
P
ass
f
ac
e
s
s
r
at
h
er
th
an
te
x
t
-
b
ased
p
ass
w
o
r
d
s
a
n
d
t
h
e
u
s
er
s
w
er
e
h
ig
h
l
y
i
n
f
l
u
en
ce
d
b
y
th
e
g
e
n
d
er
,
attr
ac
tiv
en
e
s
s
an
d
r
ac
e
o
f
t
h
e
f
ac
es
u
s
ed
[
2
0
]
.
T
h
e
P
ass
f
ac
es
p
ass
w
o
r
d
w
o
u
l
d
b
e
p
r
ed
ictab
le
in
th
is
w
a
y
.
T
h
is
i
s
s
u
e
m
a
y
b
e
co
n
tr
o
lled
b
y
ass
ig
n
i
n
g
f
ac
e
s
to
th
e
u
s
er
s
ar
b
itra
r
il
y
b
u
t
t
h
e
n
it
w
o
u
ld
b
e
m
o
r
e
d
if
f
ic
u
lt
f
o
r
th
e
u
s
er
s
to
r
e
ca
ll
s
u
c
h
p
ass
w
o
r
d
s
.
An
o
th
er
s
etb
ac
k
w
it
h
t
h
is
tec
h
n
iq
u
e
i
s
th
at
t
h
e
lo
g
in
a
n
d
r
eg
i
s
tr
atio
n
p
r
o
ce
s
s
es
ta
k
e
ti
m
e
an
d
w
h
ich
w
i
ll
ca
u
s
e
t
h
is
m
et
h
o
d
to
b
e
m
o
r
e
ti
m
e
co
n
s
u
m
in
g
co
m
p
ar
ed
to
th
e
tex
t
-
b
ased
p
ass
w
o
r
d
s
y
s
te
m
.
A
d
d
itio
n
al
s
t
u
d
ies
w
er
e
ca
r
r
ied
o
n
th
e
s
e
c
u
r
it
y
f
ea
tu
r
e
s
o
f
P
ass
Face
s
to
f
i
n
d
o
u
t
i
f
t
h
e
P
ass
f
ac
e
s
w
a
s
s
u
s
ce
p
tib
le
to
s
o
cial
e
n
g
in
ee
r
i
n
g
th
r
ea
ts
w
h
er
eb
y
th
e
h
ac
k
er
s
co
u
ld
p
er
s
u
ad
e
th
e
u
s
er
to
ex
p
lain
th
e
i
m
ag
e
t
h
e
y
w
er
e
u
s
in
g
[2
1
-
2
2
]
.
I
t
w
a
s
r
ev
ea
led
th
a
t
w
h
en
a
d
ec
o
y
i
m
ag
e
w
a
s
c
h
o
s
en
ca
r
ef
u
ll
y
t
h
at
w
a
s
j
u
s
t
li
k
e
t
h
e
u
s
er
‟
s
ch
o
s
e
n
i
m
a
g
es,
it
w
a
s
n
o
t
p
o
s
s
ib
le
f
o
r
an
o
t
h
er
p
er
s
o
n
h
av
in
g
h
ea
r
d
th
e
d
escr
ip
tio
n
o
f
t
h
e
i
m
ag
e
to
en
ter
t
h
e
p
as
s
w
o
r
d
ac
cu
r
atel
y
j
u
s
t
b
ased
o
n
th
is
i
n
f
o
r
m
atio
n
.
2
.
2
.
Déj
à
v
u Sche
m
e
Dev
elo
p
ed
in
2
0
0
0
,
th
e
d
éj
à
v
u
alg
o
r
it
h
m
allo
w
s
t
h
e
u
s
er
s
s
elec
t
an
d
r
ec
all
an
i
m
a
g
e
s
u
b
s
et
f
r
o
m
a
lar
g
er
s
a
m
p
le
to
p
r
ep
ar
e
th
e
p
o
r
tf
o
lio
[
2
3
]
.
I
n
o
r
d
er
to
lo
g
i
n
,
u
s
er
s
s
h
o
u
ld
r
e
m
e
m
b
er
t
h
e
s
elec
ted
p
o
r
tf
o
lio
‟
s
i
m
a
g
es
f
r
o
m
a
d
ec
o
y
i
m
a
g
e
c
o
llectio
n
.
I
n
th
e
te
s
t
s
y
s
te
m
,
a
p
an
el
in
cl
u
d
in
g
2
5
p
ictu
r
es
i
s
p
r
esen
ted
;
o
u
t
o
f
th
ese,
5
i
m
a
g
e
s
ar
e
i
n
cl
u
d
ed
in
u
s
er
‟
s
th
e
p
o
r
tf
o
lio
.
T
h
e
u
s
e
r
s
s
h
o
u
ld
r
e
m
e
m
b
er
al
l
i
m
a
g
e
s
o
f
th
e
ir
p
o
r
tf
o
lio
b
u
t
o
n
l
y
o
n
e
p
an
el
i
s
d
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e
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o
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et
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k
tr
a
f
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ic
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es
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ela
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s
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Mo
r
eo
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er
,
w
h
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h
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Déj
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‟
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s
p
ac
e
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ize
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ass
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o
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d
is
less
th
an
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te
x
t p
ass
w
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s
,
it is
n
o
t n
ec
es
s
ar
il
y
ea
s
ier
to
r
ec
all
th
at.
2
.
3
.
T
ria
ng
le
Sche
m
e
So
b
r
ad
o
an
d
B
ir
g
et
in
2
0
0
2
[
2
0
]
,
s
u
g
g
ested
a
n
u
m
b
er
o
f
g
r
ap
h
ic
al
p
as
s
w
o
r
d
tec
h
n
iq
u
e
s
t
o
s
o
lv
e
th
e
p
r
o
b
lem
o
f
s
h
o
u
ld
er
-
s
u
r
f
in
g
t
h
r
ea
ts
.
T
h
eir
f
ir
s
t te
ch
n
iq
u
e
was k
n
o
w
n
a
s
t
h
e
“
tr
ian
g
le
s
ch
e
m
e”
; t
h
e
u
s
er
h
a
s
to
ch
o
o
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e
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is
/
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er
p
ass
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o
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j
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t
tak
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f
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m
t
h
e
o
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ts
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is
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lay
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T
h
e
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s
er
s
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r
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e
n
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y
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h
e
en
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r
e
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ch
o
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en
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a
s
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o
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j
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ts
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at
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t t
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e
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i
s
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tag
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t
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ticatio
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ll d
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e
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ass
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ize
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m
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b
a
s
ed
o
n
r
a
n
d
o
m
clic
k
i
n
g
[
25
-
26
]
.
So
b
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o
an
d
B
ir
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et
p
r
o
p
o
s
ed
th
e
u
s
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1
0
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ts
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th
e
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g
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p
r
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s
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th
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an
d
h
ar
d
to
g
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es
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.
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h
e
less
,
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cr
ea
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g
th
e
q
u
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tit
y
o
f
o
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j
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ld
m
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k
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e
d
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p
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ar
d
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d
cr
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w
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ed
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ile
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ts
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ll‟s
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ize
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ite
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is
s
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e
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ts
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it
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m
p
le
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es
s
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d
cr
ac
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as
s
w
o
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d
.
2
.
4
.
M
o
v
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ble F
ra
m
e
Sche
m
e
T
h
e
last
s
ch
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m
e
b
y
So
b
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o
an
d
B
ir
g
et
in
2
0
0
2
[
2
0
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,
is
k
n
o
w
n
as
t
h
e
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le
Fra
m
e.
I
n
t
h
is
s
ch
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m
e,
th
er
e
ar
e
j
u
s
t
th
r
ee
p
ass
-
o
b
j
ec
ts
.
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e
o
f
t
h
e
p
ass
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o
b
j
ec
ts
w
ill
b
e
d
ir
ec
ted
to
t
h
e
m
o
v
ea
b
le
f
r
a
m
e.
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s
ar
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j
u
s
t
r
eq
u
ir
ed
to
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o
v
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y
r
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f
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a
m
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till
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en
tire
p
ass
-
o
b
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e
p
lace
s
in
a
s
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ai
g
h
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t
h
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ted
.
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ir
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s
s
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f
e
w
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e
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y
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d
o
m
l
y
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tati
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g
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r
click
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n
g
i
t
to
m
i
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i
m
ize
th
e
c
h
an
ce
s
o
f
lo
g
in
.
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v
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ele
s
s
,
t
h
is
s
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ti
m
e
co
n
s
u
m
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g
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n
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t
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t
h
e
n
u
m
er
o
u
s
n
o
n
-
p
as
s
o
b
j
ec
ts
.
2
.
5
.
P
ict
ure
P
a
s
s
w
o
rd
Sche
m
e
I
n
2
0
0
3
[
2
7
-
8
]
,
B
y
e
J
an
e
s
e
n
,
d
esig
n
ed
a
g
r
ap
h
ical
p
ass
w
o
r
d
s
ch
e
m
e
b
ased
o
n
“
p
ictu
r
e
p
ass
w
o
r
d
”
p
ar
ticu
lar
l
y
ca
ter
ed
to
m
o
b
ile
d
ev
ices
li
k
e
P
D
As.
T
h
e
u
s
er
s
h
av
e
to
f
ir
s
t
c
h
o
o
s
e
t
h
e
t
h
e
m
e
(
ca
t
an
d
d
o
g
,
s
ea
an
d
s
h
o
r
e,
an
d
o
th
er
s
)
w
h
ic
h
co
m
p
r
is
e
o
f
th
u
m
b
n
ail
p
h
o
to
s
th
r
o
u
g
h
o
u
t
t
h
e
cr
ea
tio
n
o
f
a
p
ass
w
o
r
d
.
T
h
en
,
th
e
u
s
er
s
c
h
o
o
s
e
an
d
r
eg
i
s
ter
a
s
eq
u
en
ce
o
f
t
h
e
c
h
o
s
e
n
th
u
m
b
n
ail
p
h
o
to
to
cr
ea
te
a
p
ass
w
o
r
d
.
T
h
e
u
s
er
s
ar
e
r
eq
u
ir
ed
to
r
e
m
e
m
b
er
an
d
r
ec
o
g
n
ize
th
e
p
h
o
to
s
s
ee
n
p
r
ev
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s
l
y
a
n
d
to
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ch
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n
t
h
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r
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g
h
t
o
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d
er
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tili
z
in
g
a
s
t
y
l
u
s
f
o
r
au
t
h
en
t
icatio
n
p
u
r
p
o
s
e.
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h
e
u
s
er
s
ca
n
ch
a
n
g
e
th
e
p
as
s
wo
r
d
,
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o
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e
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n
e
w
s
eq
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n
ce
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o
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ch
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g
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t
h
e
th
e
m
e
af
ter
t
h
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y
s
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cc
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d
ed
i
n
th
e
au
t
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t
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.
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h
e
r
esear
ch
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s
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ls
o
p
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p
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ed
th
at
th
e
p
r
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ce
s
s
b
e
r
ep
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ted
s
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er
al
ti
m
e
s
to
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w
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th
e
c
h
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ce
s
o
f
lo
g
g
i
n
g
in
b
y
r
a
n
d
o
m
l
y
r
o
tati
n
g
o
r
click
i
n
g
.
T
h
e
d
is
ad
v
an
ta
g
e
o
f
th
is
m
eth
o
d
is
th
e
s
m
all
p
as
s
w
o
r
d
s
p
ac
e
as
t
h
e
p
h
o
to
s
ar
e
li
m
i
ted
to
o
n
l
y
t
h
ir
t
y
p
iece
s
.
T
h
e
d
esig
n
er
s
ad
d
ed
a
s
ec
o
n
d
s
tep
to
th
e
alg
o
r
it
h
m
to
o
v
er
co
m
e
t
h
i
s
is
s
u
e.
T
h
e
u
s
er
s
ca
n
c
h
o
o
s
e
t
w
o
t
h
u
m
b
n
a
ils
s
i
m
u
lta
n
eo
u
s
l
y
to
d
esi
g
n
th
e
n
e
w
alp
h
ab
et
co
m
p
o
n
e
n
t
b
y
u
tili
z
in
g
t
h
e
s
h
i
f
t
k
e
y
to
c
h
o
o
s
e
e
ith
er
s
p
ec
ial
ch
ar
ac
ter
s
o
r
u
p
p
er
ca
s
e.
T
h
e
r
ec
all
p
r
o
ce
s
s
w
ill
b
e
m
o
r
e
co
m
p
licated
w
h
e
n
th
e
s
ec
o
n
d
s
tep
is
ad
d
ed
t
o
th
e
alg
o
r
ith
m
e
v
e
n
th
o
u
g
h
it
o
v
er
co
m
e
s
t
h
e
s
p
ac
e
p
r
o
b
lem
.
2
.
6
.
Where
i
s
Wa
ldo
(
WI
W)
Sch
e
m
e
I
n
2
0
0
3
,
Ma
n
,
et
al.
p
r
o
p
o
s
ed
th
e
s
h
o
u
l
d
er
-
s
u
r
f
in
g
r
esis
tan
t
s
ch
e
m
e
[
2
9
]
.
I
n
th
i
s
tec
h
n
iq
u
e
,
th
e
u
s
er
s
ca
n
s
elec
t
m
a
n
y
p
ict
u
r
es
as
th
e
p
ass
-
ite
m
s
.
Fe
w
v
ar
ia
n
t
s
ar
e
av
ailab
le
f
o
r
ea
ch
p
ass
-
ite
m
a
n
d
a
u
n
iq
u
e
co
d
e
is
g
iv
e
n
to
ea
c
h
v
ar
ian
t.
Du
r
i
n
g
au
t
h
en
t
icatio
n
,
s
ev
er
al
s
ce
n
e
s
a
f
e
w
p
ass
-
ite
m
s
ar
e
g
iv
e
n
to
th
e
u
s
er
.
T
h
ese
in
cl
u
d
e
m
an
y
d
ec
o
y
s
a
n
d
a
r
an
d
o
m
l
y
s
e
lecte
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1
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v
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.
2
.
7
.
Sto
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S
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Dav
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p
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th
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Sto
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c
h
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m
e
i
n
2
0
0
4
[2
1
]
as
a
c
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m
p
ar
ab
le
tech
n
iq
u
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to
P
ass
F
ac
es.
Her
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in
Sto
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,
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t
h
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ch
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.
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Co
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in
2
0
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3
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p
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HC
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s
t
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tech
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iq
u
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I
t
is
a
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ap
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p
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w
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tec
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n
iq
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n
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T
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d
.
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i
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tan
t t
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ar
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ab
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f
th
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s
tech
n
iq
u
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2
.
9
.
Weins
ha
ll Sche
m
e
W
ein
s
h
all
i
n
2
0
0
6
[3
3
]
,
in
tr
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d
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ce
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g
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ap
h
ical
p
ass
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d
tech
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e
w
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m
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f
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m
th
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p
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tf
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lio
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o
r
d
er
to
lo
g
in
.
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lo
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s
s
in
cl
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tli
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ter
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ased
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tf
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m
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p
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t
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tf
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d
m
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v
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g
r
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Af
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d
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u
s
er
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t
h
e
n
ticated
is
co
m
p
lete.
So
m
e
u
s
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r
o
r
is
allo
w
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b
u
t
th
e
u
s
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s
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ej
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ted
if
t
h
e
th
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h
o
ld
i
s
n
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t
r
ea
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w
it
h
i
n
a
f
i
x
ed
n
u
m
b
er
o
f
r
o
u
n
d
s
.
T
h
e
in
p
u
t
u
s
e
s
th
e
k
e
y
b
o
ar
d
in
s
te
ad
o
f
a
m
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u
s
e,
to
h
elp
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e
th
r
ea
t
o
f
s
h
o
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ld
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-
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r
f
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n
g
.
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y
s
te
m
a
s
s
i
g
n
ed
i
m
a
g
e
p
o
r
tf
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lio
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g
iv
e
n
to
u
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er
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a
n
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th
e
y
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ec
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t
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tr
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n
in
g
to
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m
e
m
o
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ize
th
is
p
o
r
tf
o
lio
as
it in
v
o
lv
e
s
m
a
n
y
i
m
a
g
es (
ab
o
u
t 1
0
0
)
,
b
u
t ti
m
e
ta
k
en
w
a
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n
o
t
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ec
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r
d
e
d
f
o
r
th
is
in
itial p
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s
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f
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ain
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n
g
.
2
.
1
0
.
I
m
a
g
e
P
a
s
s
S
che
m
e
Mih
aj
lo
v
(
2
0
1
1
)
[
3
4
]
s
u
g
g
est
ed
th
e
p
ass
w
o
r
d
p
atter
n
b
a
s
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o
n
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f
y
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t
h
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le
-
o
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t
im
a
g
es
to
m
a
k
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g
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ap
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ca
l
p
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w
o
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d
.
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u
s
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ch
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s
en
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h
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a
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r
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1
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p
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ttach
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User
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t
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g
[
3
5
]
.
2
.
1
1
.
WYS
WY
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Sc
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Kh
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to
av
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s
h
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f
in
g
at
tack
[
3
6
]
.
T
h
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W
YSW
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s
tr
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w
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in
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36
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,
th
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P
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ith
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w
a
s
d
esig
n
ed
to
b
e
i
m
p
en
etr
ab
le
to
s
h
o
u
ld
er
s
u
r
f
i
n
g
a
ttack
s
,
u
s
i
n
g
t
h
e
r
esear
c
h
w
h
ic
h
r
ev
ea
l
s
t
h
at
m
o
v
i
n
g
th
e
co
n
f
i
g
u
r
atio
n
f
r
o
m
m
o
u
s
e
b
ased
in
p
u
t
to
k
e
y
b
o
ar
d
in
p
u
t,
lo
w
er
s
t
h
e
p
o
s
s
ib
ili
t
y
o
f
b
ein
g
attac
k
ed
u
s
in
g
t
h
e
s
h
o
u
ld
er
s
u
r
f
i
n
g
m
et
h
o
d
.
3.
USAB
I
L
I
T
Y
ASPE
CT
S
Usab
ilit
y
i
s
a
cr
itical
co
m
p
o
n
en
t
in
d
ev
elo
p
in
g
a
g
r
ap
h
ic
al
p
ass
w
o
r
d
m
et
h
o
d
th
at
is
g
o
o
d
an
d
m
ee
t
s
th
e
n
ee
d
s
a
n
d
r
eq
u
ir
e
m
e
n
t
s
o
f
its
u
s
er
s
.
A
cc
o
r
d
in
g
to
t
h
e
I
S
O
9
2
4
1
-
1
1
s
tan
d
ar
d
[
1
7
]
,
[
2
9
]
,
[
3
6
]
,
u
s
ab
ilit
y
i
s
d
ef
in
ed
a
s
t
h
e
lev
el
at
w
h
ic
h
a
p
r
o
d
u
ct
is
u
s
ab
le
to
p
ar
ticu
lar
u
s
er
s
to
r
ea
c
h
t
h
eir
p
r
ec
is
e
o
b
j
ec
tiv
es
e
f
f
icien
tl
y
an
d
ef
f
ec
tiv
el
y
an
d
s
ati
s
f
ac
to
r
y
i
n
th
e
r
eq
u
ir
ed
co
n
tex
t.
T
h
e
m
aj
o
r
ar
g
u
m
e
n
t
w
it
h
th
e
in
tr
o
d
u
ctio
n
o
f
t
h
e
g
r
ap
h
ical
p
as
s
w
o
r
d
is
th
at
i
m
ag
es
ar
e
ea
s
i
l
y
r
e
m
e
m
b
er
ed
c
o
m
p
ar
ed
to
s
tr
i
n
g
s
o
f
te
x
ts
.
S
ev
er
al
r
esear
ch
er
s
w
h
o
co
n
d
u
cted
ea
r
l
y
s
t
u
d
ies
i
n
t
h
is
ar
ea
co
n
c
u
r
w
it
h
t
h
i
s
ar
g
u
m
e
n
t
.
An
o
th
er
u
s
ab
ilit
y
i
s
s
u
e
t
h
at
ar
is
e
s
w
it
h
th
e
R
ec
o
g
n
it
io
n
-
B
ased
ap
p
r
o
ac
h
es
is
t
h
e
ti
m
e
tak
e
n
in
t
h
e
r
eg
is
tr
atio
n
a
n
d
lo
g
g
i
n
g
in
p
r
o
ce
s
s
w
h
ic
h
is
to
o
lo
n
g
.
U
s
i
n
g
th
i
s
ap
p
r
o
ac
h
m
e
an
s
t
h
at
th
e
u
s
er
s
h
av
e
to
ch
o
o
s
e
an
i
m
a
g
e
f
r
o
m
a
co
llect
io
n
o
f
i
m
a
g
e
s
w
h
en
r
eg
is
ter
i
n
g
in
itiall
y
a
n
d
t
h
e
u
s
er
s
h
av
e
to
s
ca
n
m
an
y
i
m
a
g
es
to
p
ick
s
e
v
er
al
p
ass
i
m
ag
e
s
f
o
r
a
u
t
h
en
t
icatio
n
p
u
r
p
o
s
es.
Giv
e
n
t
h
e
ted
io
u
s
n
ess
o
f
th
is
p
r
o
ce
s
s
,
a
n
e
w
b
ie
to
th
e
g
r
ap
h
ical
p
as
s
w
o
r
d
s
e
ttin
g
w
o
u
ld
f
i
n
d
it
d
if
f
ic
u
lt
an
d
co
m
p
lex
.
Fo
llo
w
i
n
g
t
h
e
co
m
p
r
e
h
e
n
s
i
v
e
r
ev
i
e
w
o
f
t
h
e
u
s
ab
ili
t
y
attr
ib
u
te
s
in
th
e
R
ec
o
g
n
itio
n
-
B
ased
g
r
ap
h
ical
p
as
s
w
o
r
d
,
it
w
a
s
f
o
u
n
d
th
a
t
t
h
er
e
is
n
o
t
a
s
i
n
g
le
m
e
th
o
d
t
h
at
h
as
t
h
e
m
o
s
t
r
e
s
o
u
n
d
in
g
u
s
ab
ilit
y
attr
ib
u
tes.
T
h
er
ef
o
r
e,
at
th
e
en
d
o
f
t
h
i
s
r
esear
ch
,
a
s
et
o
f
u
s
ab
il
it
y
at
tr
ib
u
tes t
h
at
c
an
b
e
ap
p
lied
in
to
a
s
in
g
le
g
r
ap
h
ical
p
ass
w
o
r
d
s
y
s
t
e
m
,
w
h
ich
w
o
u
ld
b
e
ab
le
to
m
ee
t th
e
r
eq
u
ir
e
m
e
n
t
s
o
f
t
h
e
u
s
e
r
s
,
is
s
u
g
g
ested
.
I
n
ad
d
itio
n
,
th
i
s
s
t
u
d
y
ex
a
m
i
n
e
d
an
d
co
m
p
ar
ed
Su
cc
e
s
s
r
ate
s
o
n
lo
g
i
n
,
lo
g
i
n
ti
m
e
a
n
d
Me
m
o
r
ab
ilit
y
o
f
t
h
e
ex
is
t
in
g
s
y
s
te
m
s
w
h
ich
ar
e
t
h
e
u
s
ab
il
it
y
m
ea
s
u
r
es
m
o
s
t
o
f
te
n
r
ep
o
r
ted
in
u
s
er
s
t
u
d
ies
o
f
g
r
ap
h
ical
p
ass
w
o
r
d
s
.
T
h
e
s
ec
tio
n
s
t
h
at
f
o
llo
w
w
il
l
d
ef
in
e
a
n
d
d
escr
ib
e
th
e
m
aj
o
r
u
s
ab
ilit
y
f
ea
t
u
r
es
th
a
t
ca
n
b
e
em
p
lo
y
ed
i
n
th
e
p
r
esen
t
a
n
d
f
u
t
u
r
e
tech
n
iq
u
es
o
f
th
e
R
ec
o
g
n
i
tio
n
-
B
ased
g
r
a
p
h
ical
p
ass
w
o
r
d
w
h
ic
h
ca
n
b
e
class
i
f
ied
i
n
to
n
in
e
ca
teg
o
r
ies
s
u
c
h
as
User
as
s
i
g
n
ed
I
m
a
g
es,
Me
a
n
i
n
g
f
u
l
I
m
a
g
es,
C
ateg
o
r
y
o
f
I
m
ag
e
s
,
E
as
y
an
d
Fu
n
to
U
s
e,
E
as
y
to
C
r
ea
te,
E
as
y
to
E
x
e
cu
te,
E
as
y
to
lear
n
a
n
d
U
n
d
er
s
tan
d
,
E
as
y
to
C
o
r
r
ec
t,
an
d
Nice
an
d
Si
m
p
le
I
n
ter
f
ac
e.
T
h
e
f
o
llo
w
i
n
g
s
ec
ti
o
n
s
d
escr
ib
e
th
e
d
ef
i
n
itio
n
o
f
t
h
e
u
s
ab
ilit
y
f
u
n
c
tio
n
i
n
d
etail.
3
.
1
.
I
m
a
g
es
t
ha
t
a
re
M
ea
nin
g
f
ul
M
ea
n
s
t
h
at
t
h
e
i
m
a
g
e
s
ar
e
w
el
l
-
k
n
o
w
n
an
d
f
a
m
i
liar
to
th
e
u
s
er
s
.
3
.
2
.
I
m
a
g
es As
s
ig
ned by
User
s
R
esear
ch
o
n
m
e
m
o
r
ab
ilit
y
s
u
g
g
e
s
ts
t
h
at
w
h
e
n
a
p
as
s
w
o
r
d
i
s
r
an
d
o
m
l
y
ass
ig
n
ed
to
u
s
er
s
,
th
e
y
h
a
v
e
d
if
f
ic
u
lt
y
r
ec
alli
n
g
t
h
eir
p
ass
w
o
r
d
s
co
m
p
ar
ed
to
th
e
s
ce
n
ar
io
w
h
er
e
u
s
er
s
ar
e
allo
w
ed
t
o
ch
o
o
s
e
th
eir
o
w
n
p
ass
w
o
r
d
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
J
E
C
E
Vo
l.
6
,
No
.
6
,
Dec
em
b
er
201
6
:
29
3
9
–
29
4
8
2944
3
.
3
.
I
m
a
g
es Ca
t
eg
o
ry
M
ea
n
s
t
h
at
u
s
er
s
ca
n
s
el
ec
t a
c
ateg
o
r
y
o
f
i
m
a
g
es a
cc
o
r
d
in
g
t
o
th
eir
p
r
ef
er
en
ce
.
3
.
4
.
E
a
s
y
t
o
Cre
a
t
e
M
ea
n
s
u
s
er
s
ca
n
cr
ea
te
t
h
eir
g
r
ap
h
ical
p
as
s
w
o
r
d
s
ea
s
il
y
w
h
e
n
th
e
r
e
g
is
tr
at
io
n
s
tep
s
ar
e
s
i
m
p
le.
Hav
i
n
g
a
f
e
w
r
o
u
n
d
s
o
f
ch
o
o
s
in
g
a
n
d
cr
ea
tin
g
a
p
ass
w
o
r
d
as
in
th
e
Sto
r
y
p
as
s
w
o
r
d
,
m
a
k
e
s
th
e
p
r
o
ce
s
s
s
lo
w
an
d
co
m
p
licated
f
o
r
th
e
u
s
er
s
.
3
.
5
.
F
un
t
o
Use a
nd
E
a
s
y
M
ea
n
s
th
a
t
t
h
e
s
y
s
te
m
s
h
o
u
l
d
o
f
f
er
a
g
o
o
d
p
latf
o
r
m
to
c
r
ea
te
th
e
p
a
s
s
w
o
r
d
.
A
s
a
n
e
x
a
m
p
le,
t
h
e
ch
alle
n
g
e
-
r
esp
o
n
d
o
r
tr
ain
i
n
g
s
ess
io
n
ap
p
r
o
ac
h
is
u
s
ed
to
m
ak
e
u
s
er
s
f
ee
l t
h
at
t
h
e
s
y
s
te
m
i
s
ea
s
y
to
u
s
e.
3
.
6
.
E
a
s
ily
E
x
ec
ute
d
M
ea
n
s
u
s
er
s
ca
n
ex
ec
u
te
t
h
e
alg
o
r
ith
m
w
it
h
ea
s
e
w
h
en
t
h
e
r
eg
is
tr
atio
n
a
n
d
lo
g
in
i
s
d
escr
ib
ed
in
s
i
m
p
le
ea
s
y
s
tep
s
.
Ha
v
i
n
g
a
f
e
w
r
o
u
n
d
s
o
f
c
h
o
o
s
in
g
a
n
d
cr
ea
tin
g
a
p
ass
w
o
r
d
,
m
a
k
es
t
h
e
p
r
o
ce
s
s
s
lo
w
an
d
co
m
p
lica
ted
f
o
r
th
e
u
s
er
s
th
u
s
th
e
s
u
g
g
e
s
ted
alg
o
r
ith
m
f
o
r
th
e
r
eg
is
tr
atio
n
an
d
lo
g
i
n
s
h
o
u
ld
b
e
d
o
n
e
in
a
s
in
g
le
s
tep
.
3
.
7
.
Nice
a
nd
Si
m
p
le
In
t
er
f
a
ce
C
o
n
ce
n
tr
ates
o
n
th
e
u
s
er
s
‟
in
t
er
ac
tio
n
s
b
esid
es
m
a
k
i
n
g
th
e
i
n
ter
f
ac
e
a
ttra
ctiv
e.
T
h
e
ai
m
o
f
h
av
in
g
a
n
ice
a
n
d
s
i
m
p
le
i
n
ter
f
ac
e
is
to
m
ak
e
th
e
u
s
er
s
‟
i
n
ter
ac
tio
n
s
a
s
e
f
f
ic
ien
t
an
d
s
i
m
p
le
a
s
th
e
y
ca
n
.
A
g
o
o
d
in
ter
f
ac
e
d
esi
g
n
f
o
r
u
s
er
s
f
ac
ilit
ate
t
h
e
co
m
p
letio
n
o
f
t
h
e
t
ask
at
h
an
d
b
y
s
ta
y
i
n
g
a
w
a
y
f
r
o
m
u
n
n
ec
es
s
ar
y
atten
tio
n
w
it
h
a
g
o
o
d
,
ey
e
ca
tc
h
in
g
a
n
d
b
o
ld
g
r
ap
h
ic
d
esig
n
.
3
.
8
.
E
a
s
ily
Und
er
s
t
o
o
d a
nd
Le
a
r
nt
M
ea
n
s
th
at
w
h
e
n
u
n
d
er
s
tan
d
a
b
ilit
y
a
n
d
lear
n
ab
ili
t
y
f
u
n
ctio
n
s
ar
e
ad
d
ed
to
an
a
lg
o
r
it
h
m
,
th
e
s
y
s
te
m
w
il
l
b
e
ea
s
ier
to
u
n
d
er
s
tan
d
an
d
u
tili
ze
,
h
e
n
ce
lo
w
er
in
g
tr
ain
i
n
g
a
n
d
s
u
p
p
o
r
t
ex
p
en
s
es;
it
also
i
m
p
r
o
v
es
th
e
u
s
er
s
a
tis
f
ac
tio
n
an
d
lo
w
er
s
p
r
ess
u
r
e
an
d
u
n
ea
s
i
n
es
s
.
B
es
id
es,
th
e
lear
n
ab
ilit
y
f
u
n
ctio
n
w
ill
in
cr
ea
s
e
th
e
u
s
er
s
‟
p
r
o
d
u
ctiv
i
t
y
a
n
d
th
e
o
v
er
all
o
r
g
an
izatio
n
‟
s
o
p
er
atio
n
al
ef
f
ec
tiv
e
n
e
s
s
.
3
.
9
.
E
a
s
y
t
o
Co
rr
ec
t
T
h
is
f
ea
t
u
r
e
a
s
s
i
s
ts
th
e
u
s
er
s
to
ea
s
il
y
u
tili
ze
th
e
s
y
s
te
m
w
it
h
o
u
t
a
n
y
d
if
f
ic
u
lt
y
b
y
g
iv
i
n
g
h
i
n
t
s
t
o
u
s
er
s
o
r
o
p
en
in
g
s
o
m
e
w
i
n
d
o
w
s
w
h
ile
e
x
ec
u
t
in
g
to
r
ev
e
al
m
is
ta
k
e
s
m
ad
e
b
y
th
e
u
s
e
r
s
.
T
h
e
“
O”
s
y
m
b
o
l
r
ef
er
s
to
a
p
ar
ticu
lar
f
ea
tu
r
e
o
f
a
tech
n
iq
u
e
w
h
ile
th
e
“
×”
s
y
m
b
o
l
m
ea
n
s
t
h
at
t
h
e
tech
n
iq
u
e
is
m
is
s
in
g
a
s
p
e
cif
ic
f
u
n
ctio
n
as s
h
o
w
n
i
n
Fig
u
r
e
1.
Fig
u
r
e
1
.
T
h
e
U
s
ab
ilit
y
A
ttrib
u
tes o
n
E
x
is
tin
g
G
r
ap
h
ical
p
as
s
w
o
r
d
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I
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E
va
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a
tio
n
o
f R
ec
o
g
n
itio
n
B
a
s
ed
Gra
p
h
ica
l P
a
s
s
w
o
r
d
S
ch
e
mes in
Ter
ms o
f U
s
a
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ilit
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.
.
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a
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a
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a
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2945
4.
SE
CUR
I
T
Y
ASP
E
CT
S AN
D
AT
T
ACK
S
E
v
er
y
au
t
h
e
n
ticatio
n
s
y
s
te
m
s
h
o
u
ld
o
f
f
er
ac
ce
p
tab
le
p
r
o
te
ctio
n
f
o
r
its
en
v
is
io
n
ed
en
v
ir
o
n
m
e
n
t,
o
r
else
it
ca
n
n
o
t
s
ati
s
f
y
i
ts
m
ai
n
g
o
al.
A
s
u
g
g
ested
s
y
s
te
m
m
u
s
t
a
t
least
b
e
ass
e
s
s
ed
ag
ai
n
s
t
u
s
u
al
attac
k
s
.
B
ased
o
n
th
e
s
ta
n
d
ar
d
o
f
f
er
ed
b
y
De
An
g
eli
et
al
.
[
4
0
]
,
we
ca
te
g
o
r
ized
th
e
attac
k
s
o
n
v
i
s
u
al
p
ass
w
o
r
d
in
to
3
g
r
o
u
p
s
.
Gu
es
s
ab
ilit
y
:
T
h
e
p
r
o
b
ab
ilit
y
an
attac
k
er
ca
n
g
u
e
s
s
t
h
e
u
s
er
's
p
ass
w
o
r
d
.
Ob
s
er
v
ab
ili
t
y
:
T
h
e
p
r
o
b
ab
ilit
y
o
f
a
n
attac
k
er
b
ein
g
ab
le
to
o
b
s
er
v
e
th
e
au
t
h
e
n
ticatio
n
P
r
o
ce
s
s
.
R
ec
o
r
d
ab
ilit
y
:
T
h
e
ea
s
e
w
ith
w
h
ic
h
a
u
s
er
ca
n
r
ec
o
r
d
th
e
u
s
er
's
p
ass
w
o
r
d
.
I
n
th
e
f
o
llo
w
i
n
g
s
ec
tio
n
,
a
d
etai
led
s
tu
d
y
o
f
th
e
p
o
s
s
ib
le
attac
k
s
o
n
R
ec
o
g
n
itio
n
-
B
ased
g
r
ap
h
ical
p
ass
w
o
r
d
t
ec
h
n
iq
u
es
h
as
b
ee
n
co
n
d
u
ct
ed
an
d
th
e
attac
k
s
h
a
v
e
b
ee
n
id
en
ti
f
ied
an
d
d
eter
m
in
ed
.
T
h
e
p
o
s
s
ib
le
att
ac
k
s
ar
e
m
ap
p
ed
to
th
e
R
ec
o
g
n
itio
n
-
B
ased
s
ch
e
m
es.
P
o
s
s
ib
le
attac
k
s
ar
e
class
i
f
ied
i
n
to
f
i
v
e
k
i
n
d
s
o
f
attac
k
s
w
h
ich
ar
e
d
ictio
n
ar
y
,
b
r
u
te
f
o
r
ce
,
s
p
y
w
ar
e,
s
o
cial
en
g
i
n
ee
r
in
g
,
a
n
d
s
h
o
u
ld
er
-
s
u
r
f
in
g
.
T
h
ese
ar
e
th
e
p
r
esen
t a
ctiv
e
attac
k
s
o
n
th
e
R
ec
o
g
n
itio
n
-
B
ased
s
c
h
e
m
es.
4
.
1
.
Dict
io
na
ry
A
t
t
a
ck
T
h
ese
attac
k
s
ar
e
at
te
m
p
ted
b
y
r
ec
o
g
n
izin
g
p
as
s
w
o
r
d
s
th
a
t
w
il
l b
e
m
o
s
t p
r
o
b
ab
ly
s
elec
ted
an
d
u
s
in
g
th
e
m
to
h
ac
k
t
h
e
p
ass
w
o
r
d
s
y
s
te
m
atica
l
l
y
.
T
h
e
h
ac
k
er
s
at
te
m
p
t to
g
u
es
s
t
h
e
p
ass
w
o
r
d
s
p
ac
e
s
u
cc
e
s
s
f
u
ll
y
.
T
h
e
r
atio
o
f
s
u
cc
e
s
s
m
a
y
b
e
s
i
g
n
if
ican
tl
y
i
n
cr
ea
s
ed
b
y
d
ec
r
ea
s
i
n
g
t
h
e
n
u
m
b
er
o
f
p
r
o
b
ab
le
s
p
ec
u
latio
n
s
to
f
in
d
it.
T
h
ese
th
r
ea
ts
ca
n
b
e
m
ai
n
l
y
e
f
f
ec
tiv
e
if
o
r
d
er
ed
en
tr
ies
ar
e
e
m
p
lo
y
ed
to
ex
a
m
i
n
e
th
e
m
o
s
t
p
r
o
b
ab
le
p
ass
w
o
r
d
s
.
R
ec
o
g
n
itio
n
-
b
ase
d
v
is
u
al
p
a
s
s
w
o
r
d
s
ar
e
n
o
t
as
s
u
s
ce
p
tib
le
to
d
ictio
n
ar
y
attac
k
s
a
s
t
e
x
t
u
al
p
ass
w
o
r
d
s
,
b
ec
au
s
e
th
e
y
co
m
p
r
is
e
o
f
a
m
o
u
s
e
i
n
p
u
t
in
s
tea
d
o
f
a
k
e
y
b
o
ar
d
in
p
u
t.
On
l
y
th
e
P
ass
f
ac
e
is
n
o
t
r
esil
ien
t a
g
ai
n
s
t o
f
th
e
d
ictio
n
ar
y
t
h
r
ea
t a
m
o
n
g
th
e
c
u
r
r
en
t t
ec
h
n
iq
u
es.
4
.
2
.
B
rut
e
F
o
rc
e
(
E
x
ha
us
t
iv
e)
At
t
a
ck
T
h
ese
th
r
ea
ts
ca
n
b
e
d
o
n
e
s
i
m
ilar
to
th
e
d
ictio
n
ar
y
at
tack
s
,
b
u
t
th
e
d
if
f
er
en
ce
is
t
h
at
ev
e
r
y
p
o
s
s
ib
le
p
ass
w
o
r
d
i
s
g
en
er
ated
a
n
d
u
s
ed
to
attac
k
t
h
e
o
r
ig
in
al
p
ass
w
o
r
d
.
T
h
ese
o
p
tio
n
s
ar
e
p
r
io
r
itized
in
m
u
c
h
m
o
r
e
s
tr
u
n
g
th
r
ea
t
s
to
d
ec
r
ea
s
e
th
e
lik
eli
h
o
o
d
o
f
b
ein
g
p
ick
ed
,
if
t
h
ese
o
p
tio
n
s
ca
n
b
e
p
r
ed
icted
w
h
atso
ev
er
.
An
alo
g
o
u
s
to
th
e
d
ictio
n
ar
y
t
h
r
ea
ts
,
th
e
B
r
u
te
f
o
r
ce
attac
k
s
m
a
y
b
e
atte
m
p
ted
eith
er
o
n
lin
e
o
r
o
f
f
li
n
e.
T
h
e
b
en
ef
it
i
s
th
at
a
m
atc
h
w
ill
f
i
n
all
y
b
e
id
en
ti
f
ied
w
it
h
en
o
u
g
h
co
m
p
u
ti
n
g
ti
m
e
an
d
p
o
w
er
(
ex
ce
p
t
if
th
e
lo
ca
tio
n
o
f
o
n
li
n
e
t
h
r
ea
t
is
f
o
u
n
d
an
d
h
alted
b
ef
o
r
e
ex
h
a
u
s
t
i
n
g
)
.
B
u
t
d
u
e
to
lar
g
e
p
ass
w
o
r
d
s
p
ac
es,
it
m
a
y
n
o
t
b
e
p
o
s
s
ib
le
to
b
e
f
o
u
n
d
all
o
v
er
th
e
s
p
ac
e.
T
h
e
ex
h
a
u
s
ti
v
e
attac
k
,
u
n
l
ik
e
a
d
ictio
n
ar
y
th
r
ea
t,
o
f
f
er
s
a
g
r
ea
te
r
co
v
er
ag
e,
y
et
r
eq
u
ir
es
m
o
r
e
p
r
o
ce
s
s
in
g
ti
m
e
o
r
p
o
w
er
.
T
h
e
m
ai
n
p
r
o
tectio
n
ag
ai
n
s
t
s
u
ch
s
ea
r
ch
is
a
p
as
s
w
o
r
d
s
p
ac
e
th
at
is
lar
g
e
en
o
u
g
h
.
P
ass
w
o
r
d
s
p
ac
e
o
f
tex
tu
al
p
as
s
w
o
r
d
s
is
9
4
^N,
w
h
er
e
9
4
is
th
e
p
r
in
tab
le
n
u
m
b
er
o
f
ch
ar
ac
ter
s
ex
c
lu
d
i
n
g
th
e
s
p
ac
e
an
d
N
is
th
e
le
n
g
t
h
o
f
p
as
s
w
o
r
d
.
Ma
n
y
v
is
u
al
p
ass
w
o
r
d
tech
n
iq
u
es
p
r
o
v
id
e
a
p
ass
w
o
r
d
s
p
ac
e
co
m
p
ar
ab
le
t
o
th
e
tex
tu
al
p
as
s
w
o
r
d
s
o
r
b
ig
g
er
.
R
ec
o
g
n
i
tio
n
-
b
ased
v
is
u
al
p
ass
w
o
r
d
s
m
a
y
h
av
e
a
s
m
aller
s
p
ac
e
th
an
t
h
e
r
ec
all
-
b
ased
m
et
h
o
d
s
.
C
o
m
p
ar
ed
to
a
tex
tu
al
p
ass
w
o
r
d
,
it
is
m
u
c
h
m
o
r
e
d
if
f
ic
u
lt
to
atte
m
p
t
a
b
r
u
te
f
o
r
ce
attac
k
ag
ai
n
s
t
a
v
is
u
al
p
ass
w
o
r
d
.
T
o
cr
ea
te
au
to
m
atic
all
y
p
r
ec
is
e
m
o
u
s
e
g
est
u
r
es
to
co
p
y
t
h
e
u
s
er
i
n
p
u
t,
t
h
e
attac
k
p
r
o
g
r
a
m
s
ar
e
n
ee
d
ed
,
w
h
ic
h
i
s
q
u
ite
c
h
alle
n
g
in
g
f
o
r
th
e
r
ec
all
-
b
ased
v
is
u
al
p
ass
w
o
r
d
.
4
.
3
.
Sp
y
w
a
re
At
t
a
ck
I
n
th
is
a
ttack
,
f
ir
s
t
to
o
ls
ar
e
i
n
s
tal
led
o
n
t
h
e
co
m
p
u
ter
o
f
th
e
u
s
er
an
d
s
en
s
iti
v
e
d
ata
is
lo
g
g
ed
.
T
h
i
s
m
al
w
ar
e
r
ec
o
r
d
s
an
y
m
o
u
s
e
o
r
k
e
y
m
o
v
e
m
e
n
t.
T
h
en
,
th
e
r
ec
o
r
d
e
d
d
ata
w
it
h
o
u
t
t
h
e
u
s
er
‟
s
a
w
ar
e
n
es
s
i
s
co
n
v
e
y
ed
o
u
t
o
f
t
h
e
co
m
p
u
te
r
.
A
p
ar
t
f
r
o
m
a
f
e
w
cir
c
u
m
s
t
an
ce
s
,
m
er
e
u
s
e
o
f
k
e
y
lo
g
g
i
n
g
o
r
k
e
y
lis
te
n
i
n
g
s
p
y
w
ar
e
d
o
es
n
o
t
cr
ac
k
v
is
u
al
p
ass
w
o
r
d
s
,
b
ec
au
s
e
it
is
n
o
t
v
er
if
ied
w
h
et
h
er
a
g
r
ap
h
ic
al
p
ass
w
o
r
d
ca
n
b
e
ef
f
ec
tiv
e
l
y
cr
ac
k
ed
b
y
t
h
e
m
o
u
s
e
s
p
y
w
ar
e.
E
v
en
t
h
o
u
g
h
m
o
u
s
e
tr
ac
i
n
g
i
s
ef
f
ec
ti
v
el
y
s
av
e
d
,
it
is
n
o
t
s
u
f
f
icien
t
to
d
is
co
v
er
an
d
cr
ac
k
t
h
e
v
is
u
a
l
p
as
s
w
o
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d
.
B
esid
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in
f
o
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ti
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g
,
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th
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x
tr
a
d
ata
,
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u
c
h
as
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o
w
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an
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s
ize,
ar
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ess
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n
tial
to
co
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th
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s
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r
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4
.
4
.
Sh
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urf
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At
t
a
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User
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ed
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t
ials
ar
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g
ai
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e
d
b
y
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k
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x
ter
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m
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it
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a
m
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th
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d
s
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m
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er
ab
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to
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ld
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u
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g
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A
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th
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l
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ag
ai
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s
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th
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s
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ld
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.
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R
ec
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ased
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ted
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e
s
h
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ld
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.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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N
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2
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8
8
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8708
I
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5
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p
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u
r
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DIS
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r
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at
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s
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to
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all
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lex
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s
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r
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er
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s
.
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q
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t
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e
n
ticatio
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ld
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o
.
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t
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at,
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m
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m
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to
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ass
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f
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cies
an
d
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n
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a
n
d
s
h
o
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t
te
r
m
s
.
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lt
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ch
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h
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p
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w
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s
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m
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n
e
w
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s
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s
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s
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r
aised
.
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r
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x
a
m
p
le,
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u
th
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n
ticat
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t
h
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u
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s
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s
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n
g
t
h
ese
m
ec
h
a
n
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s
m
s
ta
k
es
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n
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ti
m
e
.
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h
e
u
s
er
s
m
a
in
l
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p
la
in
t
h
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n
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d
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eg
i
s
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tak
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g
t
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m
e,
p
ar
ticu
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n
-
ap
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ased
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tio
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B
ased
.
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a
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er
m
u
s
t
s
elec
t
p
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r
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r
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m
s
ev
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D
u
r
in
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a
u
t
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m
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s
t
s
ca
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ev
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p
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g
n
ize
p
ass
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,
w
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b
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lo
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g
an
d
ted
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s
.
Mo
r
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m
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f
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s
d
o
n
o
t
k
n
o
w
g
r
ap
h
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p
ass
w
o
r
d
s
;
th
u
s
,
g
r
ap
h
ical
p
ass
w
o
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d
s
ar
e
o
f
te
n
le
s
s
co
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v
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n
ien
t
to
th
e
m
co
m
p
ar
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to
tex
t
-
b
ased
p
ass
w
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r
d
s
.
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ex
t
-
b
ased
p
ass
w
o
r
d
s
n
ee
d
m
u
ch
le
s
s
s
to
r
ag
e
s
p
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e
th
an
g
r
ap
h
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p
ass
w
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d
s
;
th
u
s
,
h
u
g
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n
u
m
b
er
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f
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m
a
g
es
m
u
s
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b
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k
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t
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n
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n
tr
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atab
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An
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co
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r
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t
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ar
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ased
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eq
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d
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lar
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e
n
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m
b
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p
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r
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f
o
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.
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2088
-
8708
E
va
lu
a
tio
n
o
f R
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a
s
ed
Gra
p
h
ica
l P
a
s
s
w
o
r
d
S
ch
e
mes in
Ter
ms o
f U
s
a
b
ilit
y
.
.
.
.
(
To
u
r
a
j Kh
o
d
a
d
a
d
i)
2947
cu
r
r
en
t
v
is
u
al
p
a
s
s
w
o
r
d
s
ch
e
m
es,
y
et
t
h
ese
p
ass
w
o
r
d
s
ar
e
u
s
u
all
y
es
s
en
tial
w
h
en
u
s
er
s
f
ai
l
to
r
ec
all
p
ass
w
o
r
d
s
.
6.
CO
NCLU
SI
O
N
AND
F
U
T
U
RE
RE
SE
ARCH
T
h
is
r
esear
ch
h
as
r
ev
ie
w
ed
t
w
el
v
e
c
u
r
r
en
t
g
r
ap
h
ical
p
as
s
w
o
r
d
s
t
h
at
ar
e
R
ec
o
g
n
i
tio
n
-
B
ased
.
T
h
e
s
ec
u
r
it
y
a
n
d
u
s
ab
il
it
y
a
ttrib
u
t
es
o
f
t
h
e
r
ec
o
g
n
itio
n
-
b
ased
g
r
ap
h
ical
p
ass
w
o
r
d
s
h
a
v
e
b
ee
n
f
u
r
t
h
er
ad
d
r
ess
ed
an
d
r
ev
ie
w
ed
an
d
ea
ch
at
tr
ib
u
te
h
as
b
ee
n
d
is
c
u
s
s
ed
in
d
etail
.
L
astl
y
,
co
m
p
ar
is
o
n
tab
les
o
f
R
ec
o
g
n
itio
n
-
B
ased
alg
o
r
ith
m
s
w
er
e
m
ad
e
b
ased
o
n
t
h
e
u
s
ab
ilit
y
f
ea
t
u
r
es
a
n
d
th
e
p
o
t
e
n
tial
o
f
th
r
ea
t
s
.
I
n
co
n
cl
u
s
io
n
,
it
w
a
s
d
is
co
v
er
ed
th
at
f
r
o
m
th
e
f
ir
s
t
au
th
e
n
ticatio
n
u
s
in
g
g
r
ap
h
i
ca
l
i
m
ag
e
s
th
at
w
as
s
u
g
g
e
s
t
ed
till
n
o
w
,
m
a
n
y
r
esear
ch
er
s
h
av
e
tr
ied
to
co
m
e
u
p
w
it
h
n
e
w
tech
n
iq
u
es
o
r
m
a
k
e
t
h
e
p
r
ev
io
u
s
o
n
es
b
etter
esp
ec
iall
y
i
n
i
m
p
r
o
v
i
n
g
u
s
ab
ilit
y
a
n
d
s
ec
u
r
it
y
.
Un
f
o
r
tu
n
atel
y
,
i
m
p
r
o
v
in
g
u
s
ab
ilit
y
h
a
s
m
ad
e
t
h
e
tech
n
i
q
u
es
to
r
ed
u
ce
th
e
s
ec
u
r
it
y
ele
m
en
t
a
n
d
w
h
e
n
s
e
cu
r
it
y
i
s
e
m
p
h
asized
,
th
e
u
s
a
b
ilit
y
f
ea
tu
r
es
ar
e
co
m
p
r
o
m
i
s
ed
.
A
lth
o
u
g
h
,
b
o
th
asp
ec
ts
ar
e
n
ec
es
s
ar
y
a
n
d
cr
itical,
in
r
ea
lit
y
o
n
e
o
r
t
h
e
o
t
h
er
is
co
m
p
r
o
m
i
s
ed
.
W
e
n
o
te
f
r
o
m
T
ab
le
2
th
at
s
ev
er
al
e
x
is
t
in
g
R
ec
o
g
n
itio
n
-
B
ased
g
r
ap
h
ical
p
ass
w
o
r
d
s
ch
e
m
e
s
b
elie
v
ed
to
b
e
r
esis
t
an
t
o
r
i
m
m
u
n
e
to
ex
is
t
in
g
attac
k
s
s
u
ch
a
s
s
h
o
u
ld
er
-
s
u
r
f
i
n
g
attac
k
h
a
v
e
s
ig
n
i
f
ica
n
t
u
s
ab
ilit
y
d
r
a
w
b
ac
k
s
,
u
s
u
all
y
i
n
t
h
e
s
lo
w
lo
g
in
ti
m
e
an
d
h
i
g
h
lo
g
i
n
s
u
cc
ess
r
ate
r
eq
u
ir
ed
to
l
o
g
in
,
an
d
m
e
m
o
r
ab
ilit
y
p
r
o
b
lem
m
ak
in
g
th
e
m
les
s
s
u
itab
le
f
o
r
ev
er
y
d
a
y
a
u
t
h
en
ticatio
n
.
T
h
is
p
r
o
b
le
m
i
s
esp
ec
iall
y
r
ev
ea
led
i
n
t
h
e
R
ec
o
g
n
itio
n
-
B
ased
g
r
ap
h
ica
l
p
ass
w
o
r
d
tech
n
iq
u
e,
as
u
s
er
s
m
u
s
t
s
elec
t
p
ar
t
icu
lar
i
m
a
g
e
s
th
at
ar
e
all
s
ee
n
o
n
th
e
s
cr
ee
n
.
T
h
e
R
ec
o
g
n
itio
n
-
B
ased
g
r
ap
h
ical
p
ass
w
o
r
d
te
ch
n
iq
u
es
r
ev
ea
l
th
is
c
h
alle
n
g
e.
T
h
er
ef
o
r
e,
d
esig
n
er
s
ar
e
s
t
ill
c
h
allen
g
ed
w
i
th
cr
ea
tin
g
a
tec
h
n
iq
u
e
th
a
t
co
v
er
s
b
o
th
s
ec
u
r
it
y
a
n
d
u
s
ab
ilit
y
.
T
h
er
e
is
a
p
o
s
s
ib
ilit
y
f
o
r
f
u
tu
r
e
r
esear
c
h
es
to
p
r
o
o
f
th
is
ar
g
u
m
e
n
t a
s
t
h
e
e
x
i
s
tin
g
u
s
er
r
e
s
ea
r
ch
es
ar
e
li
m
it
ed
an
d
n
o
t c
o
n
v
i
n
ci
n
g
e
n
o
u
g
h
to
s
u
p
p
o
r
t th
e
m
ai
n
ar
g
u
m
e
n
t
t
h
at
p
eo
p
le
ar
e
b
ette
r
at
m
e
m
o
r
izi
n
g
g
r
ap
h
ical
p
as
s
w
o
r
d
s
co
m
p
ar
ed
to
tex
tu
al
p
ass
w
o
r
d
s
.
B
ased
o
n
th
e
u
s
ab
ilit
y
v
ie
w
p
o
in
t,
m
o
r
e
ef
f
o
r
t
s
s
h
o
u
ld
b
e
p
lace
d
o
n
f
i
n
d
in
g
o
u
t t
h
e
e
f
f
ec
ts
o
f
a
p
ar
ticu
lar
i
m
ag
e
u
tili
ze
d
s
u
cc
e
s
s
f
u
ll
y
a
s
g
r
ap
h
ical
p
as
s
w
o
r
d
s
,
s
t
u
d
y
i
n
g
s
p
ee
d
o
f
s
k
illed
u
s
er
s
,
an
d
f
in
d
i
n
g
o
u
t
t
h
e
b
ad
p
r
ac
tices
o
f
in
s
ec
u
r
e
p
ass
w
o
r
d
p
r
ac
tices th
at
u
s
er
s
ca
r
r
ied
o
u
t i
n
co
m
i
n
g
u
p
w
ith
g
r
ap
h
ical
p
as
s
w
o
r
d
s
.
ACK
NO
WL
E
D
G
E
M
E
NT
S
T
h
is
w
o
r
k
i
s
p
ar
tiall
y
s
u
p
p
o
r
ted
b
y
g
r
a
n
ts
GUP
T
ier
1
,
2
0
1
4
-
2
0
1
5
w
it
h
Vo
te
No
.
0
5
H6
1
,
GUP
T
ier
1
w
ith
Vo
te
No
.
1
1
H3
9
,
2
0
1
5
-
2
0
1
7
,
an
d
Ma
lay
s
ia
-
J
ap
an
an
d
I
n
ter
n
atio
n
al
I
n
s
tit
u
te
o
f
T
ec
h
n
o
lo
g
y
a
n
d
(
MJ
I
I
T
)
o
f
Un
i
v
er
s
iti
T
ek
n
o
l
o
g
i
Ma
la
y
s
ia
(
UT
M)
R
esear
c
h
Gr
an
t
w
it
h
Vo
te
No
.
4
J
0
4
4
,
Min
i
s
tr
y
o
f
Hi
g
h
er
E
d
u
ca
tio
n
(
Mo
HE
)
,
2
0
1
2
-
2
0
1
7
.
RE
F
E
R
E
NC
E
S
[1
]
A
.
P
.
S
a
b
z
e
v
a
r
a
n
d
A
.
S
tav
ro
u
,
“
Un
iv
e
rsa
l
m
u
lt
i
-
f
a
c
to
r
a
u
th
e
n
ti
c
a
ti
o
n
u
si
n
g
g
ra
p
h
ica
l
p
a
ss
w
o
rd
s
,”
i
n
Pro
c
e
e
d
i
n
g
s
o
f
t
h
e
2
0
0
8
IEE
E
I
n
ter
n
a
ti
o
n
a
l
C
o
n
fer
e
n
c
e
o
n
S
i
g
n
a
l
Im
a
g
e
T
e
c
h
n
o
lo
g
y
a
n
d
I
n
ter
n
e
t
B
a
se
d
S
y
ste
ms
,
p
p
.
6
2
5
–
6
3
2
,
2
0
0
8
.
[2
]
P.
S
h
i,
e
t
a
l
.
,
“
A
P
IN en
tr
y
sc
h
e
m
e
re
sista
n
t
to
r
e
c
o
rd
in
g
-
b
a
se
d
sh
o
u
ld
e
r
-
su
rf
in
g
,”
i
n
Pro
c
e
e
d
in
g
s o
f
th
e
2
0
0
9
T
h
ir
d
In
ter
n
a
t
io
n
a
l
C
o
n
fer
e
n
c
e
o
n
Eme
rg
in
g
S
e
c
u
rity I
n
fo
rm
a
ti
o
n
,
S
y
ste
ms
a
n
d
T
e
c
h
n
o
lo
g
ies
,
p
p
.
2
3
7
–
241
,
2
0
0
9
.
[3
]
L
.
S
o
b
ra
d
o
a
n
d
J.
C.
Birg
e
t,
“
G
ra
p
h
ica
l
p
a
ss
w
o
rd
s,
”
T
h
e
R
u
tg
e
rs
S
c
h
o
la
r,
A
n
El
e
c
tro
n
ic
B
u
ll
e
ti
n
o
f
Un
d
e
rg
ra
d
u
a
te
Res
e
a
rc
h
,
Ca
md
e
n
Ne
w
J
e
rs
e
y
,
v
o
l/
issu
e
:
4
(2
0
0
2
)
,
2
0
0
7
.
[4
]
X
.
S
u
o
,
e
t
a
l.
,
“
A
n
a
l
y
sis
a
n
d
d
e
sig
n
o
f
g
ra
p
h
ica
l
p
a
ss
w
o
rd
tec
h
n
iq
u
e
s
,”
Ad
v
.
Vi
su
a
l
Co
m
p
u
t
.
,
v
o
l.
4
2
9
2
,
p
p
.
7
4
1
–
749
,
2
0
0
6
.
[5
]
T
.
Tak
a
d
a
,
“
F
a
k
e
P
o
i
n
ter:
a
n
a
u
th
e
n
ti
c
a
ti
o
n
sc
h
e
m
e
f
o
r
im
p
ro
v
i
n
g
se
c
u
rit
y
a
g
a
in
st
p
e
e
p
in
g
a
tt
a
c
k
s
u
sin
g
v
id
e
o
c
a
m
e
ra
s
,”
i
n
T
h
e
S
e
c
o
n
d
I
n
ter
n
a
ti
o
n
a
l
C
o
n
fer
e
n
c
e
o
n
M
o
b
i
le
Ub
iq
u
it
o
u
s
Co
m
p
u
t
in
g
,
S
y
ste
m
s,
S
e
rv
ice
s
a
n
d
T
e
c
h
n
o
l
o
g
ies
,
p
p
.
3
9
5
–
400
,
2
0
0
8
.
[6
]
F.
T
a
ri,
e
t
a
l.
,
“
A
c
o
m
p
a
riso
n
o
f
p
e
rc
e
i
v
e
d
a
n
d
re
a
l
sh
o
u
l
d
e
r
-
su
rf
in
g
risk
s
b
e
twe
e
n
a
lp
h
a
n
u
m
e
ric
a
n
d
g
ra
p
h
ica
l
p
a
ss
w
o
rd
s
,”
i
n
Pro
c
e
e
d
in
g
s o
f
th
e
S
e
c
o
n
d
S
y
mp
o
siu
m
o
n
Us
a
b
le P
riv
a
c
y
a
n
d
S
e
c
u
rity
,
p
p
.
5
6
–
66
,
2
0
0
6
.
[7
]
S.
W
ied
e
n
b
e
c
k
,
e
t
a
l.
,
“
P
a
ss
P
o
i
n
ts:
d
e
sig
n
a
n
d
lo
n
g
it
u
d
in
a
l
e
v
a
lu
a
ti
o
n
o
f
a
g
ra
p
h
ica
l
p
a
ss
w
o
rd
s
y
ste
m
,”
In
t.
J
.
Hu
m.
Co
mp
u
t.
S
t
u
d
.
,
v
o
l.
3
2
,
p
p
.
102
–
1
2
7
,
2
0
0
5
.
[8
]
S.
W
ied
e
n
b
e
c
k
,
e
t
a
l.
,
“
A
u
th
e
n
t
ica
ti
o
n
u
si
n
g
g
ra
p
h
ica
l
p
a
ss
w
o
r
d
s:
e
ff
e
c
t
s
o
f
to
lera
n
c
e
a
n
d
i
m
a
g
e
c
h
o
ice
,”
i
n
S
y
mp
o
si
u
m o
n
Us
a
b
le P
riv
a
c
y
a
n
d
S
e
c
u
rity
,
p
p
.
1
–
12
,
2
0
0
5
.
[9
]
S.
W
ied
e
n
b
e
c
k
,
e
t
a
l.
,
“
De
sig
n
a
n
d
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Zh
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m
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n
Pro
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in
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2
1
st
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ter
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1
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H.
L
.
A
ra
sh
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l.
,
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ra
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2
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.
[1
2
]
N.
W
rig
h
t,
e
t
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l.
,
“
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e
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re
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rd
s,
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in
Pr
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Ei
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mp
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a
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c
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n
d
S
e
c
u
rity
,
p
p
.
8
,
2
0
1
2
.
Evaluation Warning : The document was created with Spire.PDF for Python.
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:
2
0
8
8
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8708
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C
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Vo
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6
,
No
.
6
,
Dec
em
b
er
201
6
:
29
3
9
–
29
4
8
2948
[1
3
]
Z.
Erl
ic
h
a
n
d
M
.
Zv
iran
,
“
A
u
th
e
n
ti
c
a
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m
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th
o
d
s
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r
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p
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ter
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s
se
c
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rit
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,
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c
y
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lo
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e
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o
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i
n
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1
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p
p
.
2
8
8
-
2
9
3
,
2
0
0
9
.
[1
4
]
L
.
L
a
z
a
r,
e
t
a
l.
,
“
P
e
rso
n
a
li
z
e
d
c
o
g
n
it
iv
e
p
a
ss
w
o
rd
s:
a
n
e
x
p
lo
ra
to
ry
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ss
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ss
m
e
n
t,
”
In
fo
rm
a
ti
o
n
M
a
n
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g
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me
n
t
&
Co
mp
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ter
S
e
c
u
rity
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v
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l.
1
9
,
p
p
.
2
5
-
4
1
,
2
0
1
1
.
[1
5
]
R.
Bid
d
le,
e
t
a
l.
,
“
G
ra
p
h
ica
l
p
a
ss
w
o
rd
s:
Lea
rn
in
g
f
ro
m
th
e
f
irst
tw
e
l
v
e
y
e
a
r
s,
”
ACM
Co
mp
u
ti
n
g
S
u
rv
e
y
s
(
CS
UR)
,
v
o
l.
4
4
,
p
p
.
1
9
,
2
0
1
2
.
[1
6
]
S
.
Ko
m
a
n
d
u
ri
a
n
d
D.
R.
Hu
tch
in
g
s,
“
Ord
e
r
a
n
d
e
n
tro
p
y
in
p
ictu
re
p
a
ss
w
o
rd
s,
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in
Pro
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e
e
d
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g
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e
2
0
0
8
,
p
p
.
1
1
5
-
1
2
2
,
2
0
0
8
.
[1
7
]
A
.
P
a
tri
c
k
,
e
t
a
l.
,
“
HCI an
d
se
c
u
ri
ty
s
y
ste
m
s,
”
2
0
0
3
.
[1
8
]
H.
Ga
o
,
e
t
a
l.
,
“
A
n
e
w
g
r
a
p
h
ica
l
p
a
ss
w
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rd
sc
h
e
m
e
r
e
sista
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t
to
sh
o
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l
d
e
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su
rf
in
g
,
”
in
Cy
b
e
rwo
rld
s
(
CW
),
2
0
1
0
In
ter
n
a
t
io
n
a
l
C
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fer
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n
,
p
p
.
1
9
4
-
1
9
9
,
2
0
1
0
.
[1
9
]
S
.
Bro
sto
f
f
a
n
d
M
.
A
.
S
a
ss
e
,
“
Are
P
a
ss
f
a
c
e
s
m
o
re
u
sa
b
le
th
a
n
p
a
ss
w
o
rd
s?
A
f
ield
tri
a
l
in
v
e
stig
a
t
io
n
,
”
in
Peo
p
le
a
n
d
C
o
m
p
u
ter
s X
IV
—
Us
a
b
il
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y
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r
El
se
!
e
d
:
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p
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g
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r
,
p
p
.
4
0
5
-
4
2
4
,
2
0
0
0
.
[2
0
]
L
.
S
o
b
ra
d
o
a
n
d
J.
C.
Birg
e
t,
“
G
ra
p
h
ica
l
p
a
ss
w
o
rd
s,
”
T
h
e
Ru
t
g
e
rs
S
c
h
o
la
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a
n
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lec
tro
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ic
Bu
ll
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ti
n
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n
d
e
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ra
d
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t
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rc
h
,
v
o
l.
4
,
p
p
.
2
0
0
2
,
2
0
0
2
.
[2
1
]
D.
Da
v
is,
e
t
a
l.
,
“
On
Us
e
r
Ch
o
ice
in
G
ra
p
h
ica
l
P
a
ss
w
o
rd
S
c
h
e
m
e
s,
”
in
US
ENI
X
S
e
c
u
rity
S
y
mp
o
si
u
m
,
p
p
.
11
,
2
0
0
4
.
[2
2
]
D.
T
.
L
e
v
in
,
“
Ra
c
e
a
s
a
v
isu
a
l
f
e
a
tu
re
:
u
si
n
g
v
isu
a
l
se
a
rc
h
a
n
d
p
e
rc
e
p
tu
a
l
d
isc
rim
in
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ti
o
n
tas
k
s
to
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n
d
e
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n
d
f
a
c
e
c
a
teg
o
ries
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n
d
th
e
c
ro
ss
-
ra
c
e
re
c
o
g
n
it
io
n
d
e
f
icit,
”
J
o
u
r
n
a
l
o
f
Exp
e
rime
n
ta
l
Psy
c
h
o
lo
g
y
:
Ge
n
e
ra
l
,
v
o
l
.
1
2
9
,
p
p
.
5
5
9
,
2
0
0
0
.
[2
3
]
R.
Dh
a
m
ij
a
a
n
d
A
.
P
e
rrig
,
“
D´
e
j`
a
V
u
:
a
u
se
r
st
u
d
y
u
sin
g
im
a
g
e
s
f
o
r
a
u
th
e
n
ti
c
a
ti
o
n
,
”
Pr
o
c
e
e
d
in
g
s
o
f
t
h
e
9
t
h
c
o
n
fer
e
n
c
e
o
n
U
S
ENIX
S
e
c
u
rity S
y
mp
o
siu
m
,
De
n
v
e
r,
C
o
lo
ra
d
o
,
v
ol
.
9,
2
0
0
0
.
[2
4
]
X
.
S
u
o
,
e
t
a
l.
,
“
G
ra
p
h
ica
l
p
a
ss
w
o
rd
s:
A
su
rv
e
y
,
”
in
Co
mp
u
ter
S
e
c
u
rity
Ap
p
l
ica
ti
o
n
s
Co
n
fer
e
n
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e
,
2
1
st
An
n
u
a
l
,
v
o
l
.
10
,
p
p
.
4
7
2
,
2
0
0
5
.
[2
5
]
A
.
H.
L
a
sh
k
a
ri,
e
t
a
l
.
,
“
A
S
e
c
u
r
e
Re
c
o
g
n
it
io
n
Ba
se
d
G
ra
p
h
ica
l
P
a
ss
w
o
rd
b
y
W
a
ter
m
a
rk
in
g,
”
in
Co
mp
u
ter
a
n
d
In
fo
rm
a
t
io
n
T
e
c
h
n
o
l
o
g
y
(
CIT
),
2
0
1
1
IEE
E
1
1
th
I
n
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
,
p
p
.
1
6
4
-
1
7
0
,
2
0
1
1
.
[2
6
]
K.
U.
W
e
i
-
Ch
i,
e
t
a
l.
,
“
A
S
e
c
to
r
-
Ba
se
d
G
r
a
p
h
ica
l
P
a
ss
w
o
rd
S
c
h
e
m
e
w
it
h
Re
sista
n
c
e
to
L
o
g
i
n
-
Re
c
o
rd
i
n
g
A
tt
a
c
k
s
,”
IEI
CE
T
RA
N
S
ACT
ION
S
o
n
I
n
fo
r
ma
ti
o
n
a
n
d
S
y
ste
ms
,
v
o
l/
issu
e
:
9
8
(4
),
pp.
8
9
4
-
9
0
1
,
2
0
1
5
.
[2
7
]
W
.
Ja
n
se
n
,
“
A
u
th
e
n
ti
c
a
ti
n
g
m
o
b
il
e
d
e
v
ice
u
se
rs
th
ro
u
g
h
im
a
g
e
se
lec
ti
o
n
,
”
T
h
e
I
n
ter
n
e
t
S
o
c
iet
y
:
Ad
v
a
n
c
e
s
in
L
e
a
rn
in
g
,
C
o
mm
e
rc
e
a
n
d
S
e
c
u
rit
y
,
v
o
l.
1
,
p
p
.
1
8
3
-
1
9
4
,
2
0
0
4
.
[2
8
]
W
.
Ja
n
se
n
,
“
A
u
th
e
n
ti
c
a
ti
n
g
u
se
rs
o
n
h
a
n
d
h
e
ld
d
e
v
ice
s,
”
in
Pro
c
e
e
d
in
g
s
o
f
th
e
Ca
n
a
d
i
a
n
I
n
fo
rm
a
t
io
n
T
e
c
h
n
o
l
o
g
y
S
e
c
u
rity S
y
mp
o
siu
m
,
2
0
0
3
.
[2
9
]
S
.
M
a
n
,
e
t
a
l.
,
“
A
G
ra
p
h
ica
l
P
a
ss
w
o
rd
S
c
h
e
m
e
S
tro
n
g
ly
Re
sist
a
n
t
to
S
p
y
w
a
re
,
”
in
S
e
c
u
rity
a
n
d
M
a
n
a
g
e
me
n
t
,
p
p
.
94
-
1
0
0
,
2
0
0
4
.
[3
0
]
A
.
F
u
lk
a
r,
e
t
a
l.
,
“
A
stu
d
y
o
f
g
ra
p
h
ica
l
p
a
ss
w
o
rd
a
n
d
v
a
rio
u
s
g
ra
p
h
ica
l
p
a
ss
w
o
rd
a
u
th
e
n
t
ica
ti
o
n
sc
h
e
m
e
s,
”
W
o
rld
,
v
o
l.
1
,
p
p
.
0
4
-
0
8
,
2
0
1
2
.
[3
1
]
M
.
Hly
w
a
,
e
t
a
l.
,
“
F
a
c
in
g
th
e
f
a
c
ts
a
b
o
u
t
im
a
g
e
t
y
p
e
in
re
c
o
g
n
i
ti
o
n
-
b
a
se
d
g
ra
p
h
ica
l
p
a
ss
w
o
rd
s,
”
in
Pro
c
e
e
d
in
g
s
o
f
th
e
2
7
th
An
n
u
a
l
C
o
mp
u
ter
S
e
c
u
ri
ty A
p
p
l
ica
ti
o
n
s C
o
n
fer
e
n
c
e
,
p
p
.
1
4
9
-
1
5
8
,
2
0
1
1
.
[3
2
]
S
.
W
ied
e
n
b
e
c
k
,
e
t
a
l.
,
“
De
sig
n
a
n
d
e
v
a
lu
a
ti
o
n
o
f
a
sh
o
u
l
d
e
r
-
su
rf
in
g
re
sis
tan
t
g
ra
p
h
ica
l
p
a
ss
w
o
rd
sc
h
e
m
e
,
”
in
Pro
c
e
e
d
in
g
s
o
f
t
h
e
wo
rk
in
g
c
o
n
fe
re
n
c
e
o
n
A
d
v
a
n
c
e
d
v
is
u
a
l
in
ter
f
a
c
e
s
,
p
p
.
1
7
7
-
1
8
4
,
2
0
0
6
.
[3
3
]
D.
W
e
in
sh
a
ll
,
“
Co
g
n
it
iv
e
a
u
t
h
e
n
ti
c
a
ti
o
n
sc
h
e
m
e
s
sa
fe
a
g
a
in
st
sp
y
w
a
r
e
,
”
in
S
e
c
u
rity
a
n
d
Priva
c
y
,
2
0
0
6
IE
EE
S
y
mp
o
si
u
m o
n
,
v
o
l
.
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