I
nte
rna
t
io
na
l J
o
urna
l o
f
E
lect
rica
l a
nd
Co
m
p
ute
r
E
ng
in
ee
ring
(
I
J
E
CE
)
Vo
l.
6
,
No
.
6
,
Decem
b
er
201
6
,
p
p
.
269
8
~
2
7
0
7
I
SS
N:
2088
-
8708
,
DOI
: 1
0
.
1
1
5
9
1
/
i
j
ec
e
.
v
6i
6
.
1
1
4
6
8
2698
J
o
ur
na
l ho
m
ep
a
g
e
:
h
ttp
:
//ia
e
s
jo
u
r
n
a
l.c
o
m/o
n
lin
e/in
d
ex
.
p
h
p
/I
JE
C
E
Virtual M
a
inte
na
nce,
R
ea
lity, and
Sy
ste
m
s
:
A
Revie
w
K
o
uro
us
h J
ena
b
1
,
Sa
eid M
o
s
lehpo
ur
2
,
Sa
m
K
ho
ury
3
1
F
a
c
u
lt
y
o
f
Co
ll
e
g
e
o
f
Bu
sin
e
ss
,
A
th
e
n
s S
tate
Un
iv
e
rsit
y
,
A
th
e
n
s,
AL
,
US
A
2
F
a
c
u
lt
y
o
f
Co
ll
e
g
e
o
f
En
g
in
e
e
rin
g
,
Ha
rtf
o
rd
Un
iv
e
rsit
y
,
W
e
st Ha
rt
f
o
rd
,
CT
,
USA
3
F
a
c
u
lt
y
o
f
th
e
Div
isio
n
o
f
Bu
sin
e
ss
,
S
p
rin
g
Hill
Co
ll
e
g
e
,
A
L
,
US
A
Art
icle
I
nfo
AB
ST
RAC
T
A
r
ticle
his
to
r
y:
R
ec
eiv
ed
J
u
n
7
,
2
0
1
6
R
ev
i
s
ed
Sep
2
0
,
2
0
1
6
A
cc
ep
ted
Sep
3
,
2
0
1
6
V
irt
u
a
l
Re
a
li
ty
is
a
c
o
m
p
u
ter
-
g
e
n
e
ra
ted
,
m
o
c
k
e
n
v
iro
n
m
e
n
t
th
a
t
c
a
n
a
ll
o
w
p
e
o
p
le
to
i
n
tera
c
t
w
it
h
it
i
n
a
se
e
m
in
g
l
y
re
a
l
w
a
y
b
y
u
sin
g
c
e
rtai
n
ty
p
e
s
o
f
sp
e
c
ialize
d
e
q
u
i
p
m
e
n
t.
It
is
m
a
in
ly
u
se
d
f
o
r
train
in
g
o
r
e
d
u
c
a
ti
o
n
a
l
p
u
rp
o
se
s
a
n
d
a
ll
o
w
s
f
o
r
“
re
a
l
-
li
f
e
”
train
in
g
in
a
sa
f
e
a
n
d
m
o
n
it
o
re
d
e
n
v
iro
n
m
e
n
t.
V
irt
u
a
l
trai
n
in
g
c
a
n
b
e
u
se
d
i
n
m
a
n
y
d
if
fe
re
n
t
f
ield
s
su
c
h
a
s
m
e
d
ica
l,
m
il
it
a
r
y
,
b
io
m
e
d
ica
l
re
se
a
rc
h
,
a
v
iatio
n
,
a
n
d
m
a
n
y
o
th
e
rs.
Ho
w
e
v
e
r,
th
is
p
a
p
e
r
re
v
iew
s
th
e
m
o
st
c
it
e
d
p
u
b
li
c
a
ti
o
n
s
re
late
d
to
t
h
e
a
p
p
li
c
a
ti
o
n
o
f
v
irt
u
a
l
re
a
li
t
y
f
o
r
train
in
g
in
th
e
Un
it
e
d
S
tate
s
M
il
it
a
ry
.
A
s
a
re
su
lt
,
re
se
a
rc
h
e
rs
c
a
n
f
in
d
re
se
a
rc
h
v
e
n
u
e
s b
a
se
d
o
n
th
e
c
h
a
ll
e
n
g
e
s,
risk
,
a
n
d
i
n
f
ra
stru
c
tu
re
s.
K
ey
w
o
r
d
:
Vir
tu
al
m
ai
n
ten
a
n
ce
,
r
ea
lit
y
,
an
d
s
y
s
te
m
s
Vir
tu
al
r
ea
lit
y
Vir
tu
al
tr
ai
n
in
g
Co
p
y
rig
h
t
©
2
0
1
6
In
stit
u
te o
f
A
d
v
a
n
c
e
d
E
n
g
i
n
e
e
rin
g
a
n
d
S
c
ien
c
e
.
Al
l
rig
h
ts
re
se
rv
e
d
.
C
o
r
r
e
s
p
o
nd
ing
A
uth
o
r
:
Ko
u
r
o
u
s
h
J
en
ab
,
Facu
lt
y
o
f
C
o
lleg
e
o
f
B
u
s
i
n
es
s
,
A
t
h
e
n
s
Sta
te
Un
i
v
er
s
i
t
y
,
A
t
h
e
n
s
,
AL
,
US
A
.
E
-
m
a
il: j
en
ab
@
ieee
.
o
r
g
1.
I
NT
RO
D
UCT
I
O
N
Vir
tu
al
Ma
i
n
te
n
an
ce
is
t
h
e
w
o
r
ld
o
f
v
ir
tu
al
r
ea
li
t
y
t
h
at
allo
w
s
an
i
n
d
i
v
id
u
al
to
b
e
tr
ain
ed
f
o
r
a
ce
r
tain
tas
k
.
T
h
ese
tas
k
s
co
u
l
d
in
clu
d
e
tr
ai
n
in
g
,
r
ep
air
,
an
d
s
er
v
ice
to
h
elp
m
ai
n
tai
n
ce
r
tain
eq
u
ip
m
en
t.
T
h
e
f
ield
s
o
f
tr
ai
n
i
n
g
th
at
Vir
tu
a
l
Ma
in
te
n
an
ce
in
ter
s
ec
ts
i
n
cl
u
d
e
av
iatio
n
,
co
m
b
at,
i
n
d
u
s
tr
ial,
m
ed
ical,
g
a
m
in
g
,
an
d
a
w
id
e
r
an
g
e
o
f
o
t
h
er
o
p
p
o
r
tu
n
ities
.
C
o
m
p
a
n
ies
o
f
ten
e
m
b
r
ac
e
th
is
k
i
n
d
o
f
tr
ain
in
g
b
ec
au
s
e
it
ca
n
s
av
e
th
e
co
m
p
a
n
y
m
o
n
e
y
an
d
ca
n
a
ls
o
h
elp
p
r
ep
ar
e
th
eir
e
m
p
lo
y
e
es
f
o
r
a
j
o
b
in
a
s
af
e
e
n
v
ir
o
n
m
en
t.
I
n
t
h
i
s
p
ap
er
,
th
e
f
ield
s
o
f
Vir
tu
a
l
Ma
in
ten
a
n
ce
th
a
t
w
ill
b
e
co
v
er
ed
i
n
clu
d
e
av
iatio
n
(
i
n
cl
u
d
in
g
m
ilit
ar
y
tr
ain
in
g
)
,
m
i
litar
y
(
co
m
b
at
a
n
d
tr
ain
i
n
g
)
,
an
d
ci
v
il (
m
ed
ical
an
d
g
a
m
i
n
g
)
.
Vir
tu
al
r
ea
lit
y
a
n
d
m
ai
n
te
n
a
n
ce
ca
n
b
e
f
o
u
n
d
i
n
m
an
y
o
f
o
u
r
f
ie
ld
s
.
I
n
a
v
iat
io
n
it
h
as
m
u
ltip
le
u
s
e
s
,
f
r
o
m
tr
ai
n
i
n
g
o
f
p
ilo
ts
all
th
e
w
a
y
to
t
h
e
m
a
in
te
n
a
n
ce
p
er
s
o
n
n
el
w
h
o
ta
k
e
ca
r
e
an
d
b
u
il
d
th
e
air
cr
af
t.
Fo
r
ex
a
m
p
le,
s
i
m
u
lato
r
s
p
r
ep
ar
e
p
ilo
ts
to
lear
n
h
o
w
to
f
l
y
a
n
d
ex
ec
u
te
e
m
er
g
en
c
y
p
r
o
ce
d
u
r
es
w
it
h
o
u
t
ev
e
n
s
tep
p
in
g
f
o
o
t
in
s
id
e
a
n
ac
t
u
al
air
cr
af
t.
A
t
th
e
s
a
m
e
ti
m
e,
m
ai
n
ten
a
n
ce
p
er
s
o
n
n
el
ca
n
s
t
u
d
y
a
n
d
lear
n
h
o
w
s
y
s
te
m
s
f
u
n
ctio
n
an
d
h
o
w
to
p
er
f
o
r
m
m
ai
n
te
n
a
n
ce
tas
k
to
r
ed
u
ce
th
e
r
i
s
k
o
f
d
a
m
a
g
e
to
p
ar
ts
an
d
t
h
e
air
cr
af
t.
T
h
e
Un
ited
States
m
ilit
ar
y
u
s
e
s
v
ir
t
u
al
r
ea
lit
y
a
n
d
s
i
m
u
latio
n
t
o
p
r
ep
a
r
e
s
o
ld
ier
s
f
o
r
co
m
b
at
an
d
to
r
ed
u
ce
th
e
u
s
e
o
f
r
eso
u
r
ce
s
li
k
e
a
m
m
u
n
itio
n
a
n
d
f
u
el.
I
n
th
e
civ
ilia
n
w
o
r
ld
,
v
ir
t
u
al
r
ea
lit
y
b
r
i
n
g
s
m
a
n
y
u
s
es
to
t
h
e
m
ar
k
et.
Do
cto
r
s
an
d
n
u
r
s
es
c
an
tr
ai
n
o
n
co
m
p
u
ter
s
a
s
o
p
p
o
s
ed
to
tr
ain
i
n
g
o
n
ca
d
a
v
er
s
an
d
li
v
e
s
u
b
j
ec
ts
.
Fu
r
t
h
er
m
o
r
e,
th
e
y
ca
n
tr
ai
n
o
n
t
h
e
d
eliv
er
y
o
f
b
ab
ies
an
d
o
n
d
iag
n
o
s
e
o
f
co
m
m
o
n
d
is
ea
s
es
an
d
ail
m
e
n
ts
th
a
t
p
atien
ts
m
a
y
h
a
v
e.
Vir
t
u
al
r
ea
lit
y
in
p
h
y
s
ic
s
a
n
d
e
n
g
i
n
ee
r
i
n
g
o
p
en
s
a
w
h
o
le
n
e
w
w
o
r
ld
to
d
ev
elo
p
m
e
n
t
o
f
in
d
u
s
tr
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2088
-
8708
V
ir
tu
a
l Ma
in
ten
a
n
ce
,
R
e
a
lity,
a
n
d
S
ystems
:
A
R
ev
iew
(
K
o
u
r
o
u
s
h
Je
n
a
b
)
2699
2.
CL
AS
SI
F
I
CAT
I
O
N
O
F
L
I
T
E
RA
T
UR
E
T
h
e
d
o
cu
m
e
n
t
s
an
d
s
o
u
r
ce
s
o
f
in
f
o
r
m
a
tio
n
p
er
tain
in
g
to
v
i
r
tu
al
m
a
in
te
n
a
n
ce
lis
ted
i
n
T
ab
le
1
ar
e
b
ased
o
n
t
h
e
ca
te
g
o
r
ies
s
p
lit
u
p
f
o
r
r
e
v
ie
w
.
T
ab
le
1
is
b
r
o
k
en
d
o
w
n
i
n
to
th
r
ee
ca
te
g
o
r
i
es,
w
h
ich
ar
e
C
iv
i
l
Uses
,
Militar
y
Use
s
,
an
d
A
v
ia
tio
n
Use
s
.
T
ab
le
1
.
C
lass
if
icatio
n
o
f
L
ite
r
atu
r
e
A
cc
o
r
d
in
g
to
T
o
p
ics o
f
Vir
tu
al
Ma
i
n
te
n
an
ce
N
u
mb
e
r
T
o
p
i
c
R
e
f
e
r
e
n
c
e
s
1.
C
i
v
i
l
U
se
s
1,
4,
5,
6,
8,
1
1
,
1
4
,
2
1
,
2
2
,
2
3
,
2
6
,
2
7
,
2
8
,
2
9
,
3
0
,
3
1
,
3
2
,
3
3
,
3
5
,
3
6
,
4
2
,
4
3
,
4
6
,
4
7
,
4
9
,
5
0
,
5
1
,
5
2
,
5
3
,
5
4
,
5
5
,
5
6
,
7
2
,
7
4
,
7
5
,
7
6
,
7
7
,
8
6
,
8
7
,
9
2
,
9
3
,
1
0
2
,
107
2.
M
i
l
i
t
a
r
y
U
se
s
3,
7,
9,
1
3
,
1
6
,
1
7
,
2
0
,
2
4
,
3
1
,
3
4
,
3
7
,
3
8
,
3
9
,
4
0
,
4
5
,
4
8
,
5
7
,
5
8
,
5
9
,
6
0
,
6
1
,
7
3
,
8
1
,
8
2
,
8
3
,
8
4
,
8
8
,
8
9
,
9
0
,
9
5
,
1
0
1
,
1
0
3
,
1
0
4
,
1
0
6
3.
A
v
i
a
t
i
o
n
U
se
s
2,
1
2
,
1
5
,
1
8
,
1
9
,
2
5
,
4
1
,
4
4
,
6
2
,
6
3
,
6
4
,
6
5
,
6
6
,
6
7
,
6
8
,
6
9
,
7
0
,
7
1
,
7
8
,
7
9
,
8
0
,
8
5
,
9
1
,
9
4
,
9
6
,
9
7
,
9
8
,
9
9
,
1
0
0
,
1
0
5
,
1
0
8
2
.
1
.
Civ
il Uses
Vir
tu
al
r
ea
lit
y
a
s
n
o
ted
ab
o
v
e
h
as
m
a
n
y
u
s
es
in
to
d
a
y
’
s
s
o
ci
et
y
a
n
d
j
u
s
t
i
n
t
h
e
p
as
t
t
w
e
n
t
y
y
ea
r
s
h
as
m
ad
e
v
ast
i
m
p
r
o
v
e
m
en
ts
.
T
h
e
f
ir
s
t
ca
s
e
s
o
f
v
ir
t
u
al
r
ea
lit
y
ca
m
e
to
s
u
r
f
ac
e
i
n
th
e
ea
r
l
y
1
9
5
0
s
,
w
h
en
a
cin
e
m
ato
g
r
ap
h
er
n
a
m
ed
Mo
r
to
n
H.
E
ilig
cr
ea
ted
a
s
y
s
t
e
m
o
f
f
an
s
,
s
p
ea
k
er
s
,
an
d
d
is
p
la
y
s
to
a
m
o
v
i
n
g
c
h
air
ca
lled
th
e
Se
n
s
o
r
a
m
a
[
3
3
]
.
T
h
is
g
a
v
e
t
h
e
u
s
er
a
m
o
r
e
s
u
r
r
ea
l
en
v
ir
o
n
m
en
t
to
w
atc
h
tele
v
is
i
o
n
.
L
ater
o
n
i
n
t
h
e
1
9
6
0
s
,
P
h
ilco
d
esig
n
ed
th
e
f
ir
s
t
Hel
m
et
Mo
u
n
ted
Dis
p
la
y
(
HM
D)
,
w
h
ic
h
w
a
s
ca
lled
th
e
Hea
d
s
ig
h
t
.
T
h
e
h
el
m
et
h
ad
a
s
cr
ee
n
attac
h
ed
t
o
it
th
at
w
as
at
tach
ed
to
a
ca
m
er
a
s
y
s
te
m
to
g
i
v
e
t
h
e
u
s
er
a
s
ig
h
t
o
u
t
s
id
e
o
f
th
e
h
el
m
et.
T
h
e
Hea
d
s
ig
h
t
w
a
s
th
e
b
asis
f
o
r
w
h
at
h
e
lico
p
ter
p
ilo
ts
u
s
ed
to
f
l
y
i
n
t
h
e
d
ar
k
an
d
ass
is
t
t
h
eir
v
i
s
io
n
w
h
ile
f
l
y
in
g
.
A
s
tec
h
n
o
lo
g
y
p
r
o
g
r
ess
ed
m
o
r
e
an
d
m
o
r
e
s
cien
ti
s
t
lik
e
I
v
an
S
u
t
h
er
lan
d
d
ev
elo
p
ed
ad
d
itio
n
al
HM
D
teth
er
ed
to
co
m
p
u
ter
s
to
g
iv
e
t
h
e
u
s
er
a
m
o
r
e
i
m
m
er
s
e
d
ex
p
er
ien
ce
.
Sin
ce
th
e
s
e
ea
r
l
y
d
ev
elo
p
m
e
n
ts
,
v
ir
t
u
al
r
ea
lit
y
a
n
d
t
h
eir
s
y
s
te
m
s
h
a
v
e
i
m
p
r
o
v
ed
a
n
d
e
x
p
an
d
ed
to
m
o
r
e
f
ield
s
o
t
h
er
t
h
an
j
u
s
t
en
t
er
tain
m
en
t.
Me
d
ical
p
r
o
f
es
s
io
n
als
u
s
e
v
ir
t
u
al
r
ea
lit
y
to
p
er
f
o
r
m
an
d
p
r
ac
tice
o
n
co
m
m
o
n
a
n
d
u
n
co
m
m
o
n
p
r
o
ce
d
u
r
es.
E
n
g
i
n
ee
r
s
u
s
e
v
ir
tu
a
l
r
ea
lit
y
to
d
esi
g
n
an
d
cr
ea
te
s
tr
u
c
tu
r
es
w
it
h
o
u
t
h
av
i
n
g
to
w
a
s
te
p
r
ec
io
u
s
t
i
m
e
an
d
r
eso
u
r
ce
s
.
Stu
d
e
n
t
s
an
d
e
m
p
lo
y
ee
s
u
s
e
v
ir
t
u
al
r
ea
li
t
y
f
o
r
tr
ain
i
n
g
an
d
lear
n
in
g
b
y
cr
ea
tin
g
a
n
e
n
v
ir
o
n
m
e
n
t
t
h
at
ca
n
n
o
t
b
e
cr
ea
ted
in
a
tr
ad
itio
n
al
class
r
o
o
m
s
e
tti
n
g
.
T
elec
o
m
m
u
n
icatio
n
is
a
f
iel
d
th
at
is
j
u
s
t
s
tar
ti
n
g
to
e
v
o
lv
e
i
n
to
a
m
o
r
e
e
f
f
ec
ti
v
e
f
ac
ilit
ato
r
o
f
h
u
m
an
in
te
r
ac
tio
n
.
B
ei
n
g
ab
le
to
s
p
ea
k
w
it
h
s
o
m
eo
n
e
o
r
s
ee
s
o
m
eo
n
e
o
n
t
h
e
o
th
er
s
id
e
o
f
th
e
w
o
r
ld
b
u
t f
ee
l li
k
e
t
h
e
y
ar
e
r
ig
h
t
b
esid
e
y
o
u
is
w
h
a
t
r
esear
ch
er
s
s
tr
i
v
e
f
o
r
.
So
m
e
p
eo
p
le
w
a
n
t
to
b
r
in
g
th
e
ir
f
av
o
r
i
te
s
p
o
r
t
h
o
m
e
w
it
h
th
e
m
o
r
in
s
id
e
w
h
en
w
ea
th
er
is
n
o
t
a
l
w
a
y
s
t
h
e
b
est.
Sp
o
r
ts
lik
e
g
o
l
f
h
a
v
e
b
ee
n
b
r
o
u
g
h
t
i
n
s
id
e
to
w
h
er
e
t
h
e
av
er
ag
e
p
er
s
o
n
ca
n
p
la
y
w
it
h
o
u
t
h
a
v
in
g
to
s
tep
f
o
o
t
o
u
t
s
id
e.
I
n
b
u
s
in
e
s
s
,
p
r
o
d
u
cts
ca
n
b
e
d
esig
n
ed
a
n
d
test
ed
w
it
h
o
u
t
h
a
v
i
n
g
to
f
u
ll
y
p
r
o
d
u
ce
th
e
p
r
o
d
u
ct.
T
h
is
ca
n
b
e
e
x
c
ep
tio
n
all
y
h
elp
f
u
l
to
s
ee
i
f
a
p
r
o
d
u
ct
h
as
h
ar
m
f
u
l
s
id
e
ef
f
ec
t
s
o
n
t
h
e
w
o
r
ld
o
r
p
o
p
u
latio
n
.
Go
in
g
to
s
p
ac
e
c
an
b
e
r
ea
l
ex
p
e
n
s
i
v
e,
a
n
d
d
e
m
an
d
i
n
g
o
n
a
lo
t
o
f
p
eo
p
le
f
o
r
a
s
h
o
r
t
tr
ip
.
Sp
ac
e
is
an
e
x
p
er
ien
ce
o
n
l
y
f
e
w
h
av
e
f
elt
a
n
d
s
in
ce
s
cie
n
tis
t
ca
n
n
o
t
co
n
s
tan
t
l
y
s
en
d
p
eo
p
le
t
o
s
p
ac
e
to
p
r
ep
a
r
e
th
e
m
f
o
r
w
h
at
th
e
y
w
i
ll
s
ee
,
s
c
ien
ti
s
t
h
av
e
to
b
r
in
g
th
e
f
ee
l
i
n
g
o
f
s
p
ac
e
to
th
e
astro
n
au
t.
Ma
n
y
m
ac
h
in
e
s
an
d
s
i
m
u
la
to
r
s
ca
n
g
i
v
e
an
astr
o
n
au
t
a
clo
s
e
f
ee
li
n
g
to
b
ein
g
in
s
p
ac
e
w
it
h
o
u
t
h
ar
m
i
n
g
t
h
e
m
o
r
s
p
en
d
in
g
s
o
m
u
ch
m
o
n
e
y
.
Fi
n
all
y
th
e
l
ar
g
est
ar
ea
v
ir
t
u
al
r
ea
lit
y
f
ill
s
is
e
n
ter
tain
m
e
n
t.
E
n
ter
tain
m
e
n
t
tech
n
o
lo
g
y
to
d
a
y
is
m
o
r
e
ad
v
an
ce
d
.
T
h
e
av
er
ag
e
p
er
s
o
n
ca
n
lea
v
e
r
ea
lit
y
an
d
ex
p
er
ien
ce
m
an
y
t
h
i
n
g
s
th
e
y
co
u
ld
o
n
l
y
d
r
ea
m
o
f
.
Fro
m
f
l
y
i
n
g
a
j
et,
p
la
y
i
n
g
i
n
s
tr
u
m
en
ts
an
d
s
p
o
r
ts
,
to
ev
en
b
ein
g
o
n
a
v
ac
atio
n
w
i
th
o
u
t le
av
in
g
to
g
o
o
n
a
tr
ip
.
Hea
lth
ca
r
e
i
n
th
e
w
o
r
ld
h
a
s
b
ec
o
m
e
m
o
r
e
an
d
m
o
r
e
tec
h
n
o
lo
g
icall
y
ad
v
a
n
ce
d
in
t
h
e
las
t
f
e
w
y
ea
r
s
th
an
it
e
v
er
h
as
b
ef
o
r
e.
W
ith
th
e
aid
o
f
tech
n
o
lo
g
y
,
m
ed
ica
l
p
r
o
f
ess
io
n
als
ar
e
co
n
s
ta
n
tl
y
lear
n
in
g
m
o
r
e
an
d
pr
ep
ar
in
g
to
tak
e
ca
r
e
o
f
p
at
ien
ts
ev
er
y
d
a
y
.
I
n
s
c
h
o
o
l,
s
t
u
d
en
t
s
ca
n
lear
n
to
d
ia
g
n
o
s
e
p
atien
ts
b
y
u
s
i
n
g
h
u
m
a
n
s
i
m
u
lato
r
s
w
it
h
o
u
t
t
h
e
n
ee
d
o
f
h
av
i
n
g
a
s
ick
p
er
s
o
n
in
f
r
o
n
t
o
f
t
h
e
m
.
T
h
ese
m
et
h
o
d
s
ca
n
b
e
u
s
ed
to
test
E
m
er
g
e
n
c
y
Me
d
ical
T
ec
h
n
icia
n
s
(
E
MT
)
o
n
h
o
w
t
h
e
y
r
e
s
p
o
n
d
to
ac
cid
en
ts
a
n
d
s
ce
n
e
s
,
w
h
er
e
in
t
h
is
ca
s
e
a
f
e
w
s
ec
o
n
d
s
o
r
m
i
n
u
tes
co
u
ld
b
e
s
o
m
eo
n
e’
s
l
if
e.
B
ab
ies
ar
e
b
o
r
n
ev
er
y
d
a
y
.
W
ith
t
h
e
aid
o
f
tec
h
n
o
lo
g
y
,
n
u
r
s
in
g
s
ch
o
o
ls
h
a
v
e
ad
o
p
ted
s
i
m
u
lato
r
s
th
at
ca
n
r
ec
r
ea
t
e
th
e
b
ir
t
h
i
n
g
p
r
o
ce
s
s
an
d
te
ac
h
p
eo
p
le
w
h
at
to
ex
p
ec
t
w
i
th
o
u
t
h
a
v
in
g
to
b
e
i
n
a
r
o
o
m
p
u
tti
n
g
m
o
r
e
s
tr
es
s
o
n
th
e
m
o
t
h
er
o
r
h
ar
m
i
n
g
th
e
b
ab
y
.
Vir
tu
al
r
ea
lit
y
ca
n
h
elp
d
o
cto
r
s
p
r
ac
tice
o
p
e
r
atin
g
p
r
o
ce
d
u
r
es
o
n
a
co
m
p
u
ter
w
it
h
o
u
t
h
a
v
i
n
g
a
h
u
m
a
n
s
er
v
in
g
as
t
h
eir
f
ir
s
t
s
u
b
j
ec
t,
w
h
ich
r
ed
u
ce
s
t
h
e
d
o
cto
r
s
’
s
tr
es
s
b
y
n
o
t
h
a
v
in
g
a
p
er
s
o
n
’
s
lif
e
i
n
th
eir
h
a
n
d
s
.
P
o
s
t
-
T
r
au
m
a
tic
Stre
s
s
Dis
o
r
d
er
(
PT
SD)
an
d
o
th
er
p
atien
ts
d
ea
li
n
g
w
it
h
m
en
tal
d
is
o
r
d
er
s
o
r
illn
ess
e
s
ca
n
u
s
e
v
ir
t
u
al
r
ea
lit
y
as
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
,
Decem
b
er
201
6
:
2
6
9
8
–
2
7
0
7
2700
th
er
ap
y
to
h
elp
p
atien
ts
r
ea
c
h
a
m
o
r
e
h
ea
lt
h
y
s
tate.
Vir
t
u
al
r
ea
lit
y
is
a
lar
g
e
h
elp
i
n
t
h
e
m
ed
ical
f
ield
f
o
r
ev
er
y
o
n
e,
b
u
t
it
is
n
o
t
a
d
ir
ec
t
r
ep
lace
m
e
n
t
f
o
r
ca
d
av
er
s
an
d
test
in
g
,
y
et
it
ca
n
b
e
a
g
r
ea
t
to
o
l
f
o
r
ev
er
y
o
n
e
f
r
o
m
t
h
e
p
atien
t to
t
h
e
d
o
cto
r
.
I
n
th
e
en
g
i
n
ee
r
in
g
w
o
r
ld
,
tech
n
o
lo
g
y
a
n
d
v
ir
t
u
al
r
ea
lit
y
ar
e
u
s
ed
in
e
v
er
y
s
tep
o
f
t
h
e
d
esig
n
p
r
o
ce
s
s
.
Fro
m
th
e
f
ir
s
t
id
ea
an
d
co
n
ce
p
t
all
th
e
w
a
y
t
h
r
o
u
g
h
t
h
e
co
n
s
t
r
u
ctio
n
p
h
a
s
e
an
d
te
s
ti
n
g
p
h
as
e.
Usi
n
g
p
r
o
g
r
a
m
s
lik
e
C
o
m
p
u
ter
-
aid
ed
d
esig
n
(
C
A
D)
an
d
o
th
er
3
D
g
en
er
ati
n
g
p
r
o
g
r
a
m
s
,
en
g
i
n
ee
r
s
ca
n
cr
ea
te
th
eir
id
ea
s
an
d
co
n
ce
p
ts
o
n
a
s
cr
ee
n
m
u
c
h
f
aster
th
a
n
b
u
ild
i
n
g
m
o
c
k
v
er
s
io
n
s
o
r
s
m
aller
s
ca
les
o
f
th
e
d
es
ig
n
.
I
n
t
h
e
co
m
p
u
ter
,
th
e
en
g
i
n
ee
r
s
ca
n
lo
o
k
f
o
r
f
au
lt
s
in
t
h
e
d
esi
g
n
o
r
f
la
w
s
i
n
th
e
p
r
o
d
u
ct’
s
ae
s
th
et
ic
lo
o
k
.
On
ce
co
m
p
leted
,
it
ca
n
t
h
e
n
b
e
test
ed
o
n
th
e
co
m
p
u
ter
u
s
i
n
g
s
o
f
t
w
a
r
e
li
k
e
Au
to
C
A
D.
A
u
to
C
A
D
ca
n
b
r
in
g
t
h
e
o
b
j
ec
t
to
li
f
e
a
n
d
m
ak
e
it
f
u
n
ctio
n
li
k
e
it
w
o
u
ld
i
n
r
ea
l
li
f
e.
E
n
g
i
n
ee
r
s
ca
n
m
a
k
e
i
t
b
r
ea
k
,
test
its
li
m
it
s
,
f
i
n
d
co
m
m
o
n
f
au
lt
s
a
n
d
g
o
b
ac
k
t
o
th
e
d
esi
g
n
p
r
o
ce
s
s
to
f
i
x
t
h
e
m
.
O
n
ce
s
ati
s
f
ied
th
e
p
r
o
d
u
ct
ca
n
b
e
b
u
il
t
f
o
r
f
u
r
t
h
er
te
s
ti
n
g
a
n
d
f
i
n
all
y
s
e
n
t
to
th
e
p
u
b
lic
as
a
f
in
a
l
p
r
o
d
u
ct.
E
n
g
i
n
ee
r
s
u
s
e
v
ir
t
u
al
r
ea
l
it
y
i
n
co
n
s
tr
u
ctio
n
an
d
b
u
ild
in
g
s
,
t
h
e
au
to
m
o
b
ile
in
d
u
s
tr
y
,
av
iatio
n
,
tec
h
n
o
lo
g
y
,
an
d
p
r
etty
m
u
c
h
o
n
m
o
s
t
o
f
t
h
e
p
r
o
d
u
cts
w
e
u
s
e
to
d
ay
.
T
h
e
s
a
m
e
co
n
ce
p
t
ca
n
b
e
ap
p
lied
to
ar
t
an
d
cr
af
ti
n
g
.
Mo
r
e
an
d
m
o
r
e
p
eo
p
le
ar
e
d
esig
n
i
n
g
lo
g
o
s
,
f
as
h
io
n
,
an
d
ar
t
o
n
a
co
m
p
u
ter
s
cr
ee
n
o
r
tab
let
as
o
p
p
o
s
ed
to
p
ap
er
an
d
p
en
cil.
W
h
en
d
e
s
ig
n
ed
o
n
a
co
m
p
u
ter
,
co
m
m
o
n
m
i
s
h
ap
s
o
f
t
h
e
ele
m
e
n
t
s
o
r
ar
t
g
ett
in
g
d
a
m
ag
ed
o
n
tr
an
s
p
o
r
t
ca
n
ea
s
il
y
b
e
a
v
o
id
ed
.
On
ce
f
i
n
is
h
ed
,
th
eir
f
i
n
al
p
iece
ca
n
b
e
p
o
r
ted
an
d
s
en
t
o
u
t
w
ith
a
f
e
w
clic
k
s
o
f
a
b
u
tto
n
an
d
s
ee
n
b
y
m
a
n
y
p
eo
p
le
ac
r
o
s
s
th
e
w
o
r
ld
.
E
d
u
ca
tio
n
s
y
s
te
m
s
ac
r
o
s
s
t
h
e
w
o
r
ld
v
ar
y
d
ep
en
d
i
n
g
o
n
w
h
e
r
e
th
e
s
t
u
d
en
t
s
t
u
d
ies.
C
o
m
p
u
ter
s
h
a
v
e
b
ee
n
i
n
co
r
p
o
r
a
ted
in
m
o
r
e
p
u
b
lic
an
d
p
r
i
v
ate
s
ch
o
o
ls
f
o
r
y
o
u
n
g
er
a
g
es
to
i
n
cr
ea
s
e
t
h
eir
av
ailab
le
m
et
h
o
d
s
o
f
lear
n
in
g
.
Vir
tu
a
l
r
ea
lit
y
i
n
th
e
class
r
o
o
m
s
b
r
in
g
ev
e
n
m
o
r
e
in
ter
ac
ti
v
e
lear
n
i
n
g
f
o
r
ch
ild
r
en
an
d
y
o
u
n
g
ad
u
lt
s
w
it
h
to
o
ls
li
k
e
d
ig
ital
w
h
ite
b
o
ar
d
s
co
n
n
ec
ted
to
th
e
co
m
p
u
ter
as
a
d
is
p
la
y
an
d
a
w
r
ite
o
n
b
o
ar
d
.
I
n
co
lleg
es,
s
tu
d
e
n
ts
w
it
h
tec
h
n
o
lo
g
ical
b
ased
d
eg
r
ee
s
s
p
e
n
d
m
o
s
t
o
f
th
eir
cla
s
s
es
o
n
a
co
m
p
u
ter
co
n
n
ec
ted
to
o
t
h
er
co
m
p
u
ter
s
f
o
r
lect
u
r
es.
P
r
o
jects
an
d
a
s
s
i
g
n
m
e
n
t
s
ar
e
all
co
m
p
leted
an
d
t
u
r
n
ed
i
n
t
h
r
o
u
g
h
tec
h
n
o
lo
g
y
.
B
u
s
i
n
ess
e
s
ar
e
in
co
r
p
o
r
atin
g
th
e
s
a
m
e
id
ea
s
a
n
d
p
r
o
ce
s
s
es
in
to
tr
ain
in
g
t
h
eir
e
m
p
lo
y
ee
s
to
w
o
r
k
in
t
h
eir
f
ac
ilit
ies.
C
o
m
p
u
ter
b
ased
tr
ai
n
in
g
f
o
r
s
af
et
y
,
p
r
o
ce
s
s
es,
a
n
d
to
k
ee
p
th
e
e
m
p
lo
y
ee
u
p
-
to
-
d
ate
o
n
th
e
co
m
p
a
n
y
is
a
co
m
m
o
n
p
r
ac
tice.
I
t
h
elp
s
t
h
e
e
m
p
lo
y
ee
r
etain
m
o
r
e
k
n
o
w
led
g
e
a
s
o
p
p
o
s
ed
to
th
e
s
tan
d
ar
d
in
s
tr
u
cto
r
lectu
r
i
n
g
to
s
t
u
d
en
t
s
i
n
a
p
lain
class
r
o
o
m
.
I
n
t
h
e
w
o
r
ld
,
s
p
o
r
ts
is
u
s
ed
as
a
lar
g
e
f
o
r
m
o
f
e
n
ter
tai
n
m
en
t,
f
it
n
es
s
,
a
n
d
to
j
u
s
t
p
as
s
t
h
e
ti
m
e
w
it
h
f
r
ien
d
s
o
r
f
a
m
il
y
.
Vir
tu
a
l
r
ea
lit
y
h
as
ad
v
an
ce
d
b
y
in
co
r
p
o
r
atin
g
s
p
o
r
ts
i
n
to
th
e
tec
h
n
o
l
o
g
ical
w
o
r
ld
.
Fo
r
in
s
ta
n
ce
,
g
o
l
f
ca
n
b
e
p
la
y
ed
in
s
id
e
o
n
a
p
r
o
j
ec
to
r
w
ith
a
n
ele
ctr
o
n
ic
clu
b
.
T
h
e
p
lay
er
ca
n
p
r
o
j
ec
t
a
d
is
p
lay
o
n
a
w
a
ll
a
n
d
p
la
y
g
o
l
f
w
h
en
e
v
e
r
th
e
y
f
ee
l
li
k
e
i
t.
W
h
e
n
Ni
n
t
en
d
o
r
elea
s
ed
it
s
co
n
s
o
le
th
e
Nin
te
n
d
o
W
ii,
th
eir
lar
g
est
g
a
m
e
s
eller
w
as
W
ii
S
p
o
r
ts
.
T
h
e
u
s
er
ca
n
p
la
y
m
u
lti
p
le
s
p
o
r
ts
li
k
e
te
n
n
is
,
b
aseb
all
,
g
o
l
f
,
an
d
b
o
w
li
n
g
in
t
h
e
co
m
f
o
r
t
o
f
t
h
eir
o
w
n
h
o
m
e.
T
h
e
W
ii
also
r
elea
s
ed
a
g
a
m
e
ca
lled
W
ii
Fi
t,
w
h
er
e
t
h
e
u
s
er
co
u
ld
e
x
er
cise
an
d
g
et
i
n
s
h
ap
e
lik
e
t
h
e
y
w
er
e
in
a
g
y
m
.
I
n
s
cie
n
ce
f
ictio
n
b
o
o
k
s
a
n
d
m
o
v
ie
s
,
tal
k
i
n
g
to
s
o
m
eo
n
e
el
s
e
v
ia
a
h
o
lo
g
r
ap
h
ic
i
m
a
g
e
o
r
th
r
o
u
g
h
a
m
o
n
ito
r
o
r
s
cr
ee
n
w
as
al
w
a
y
s
a
th
o
u
g
h
t
o
f
th
e
f
u
tu
r
e.
I
n
to
d
a
y
’
s
s
o
ciet
y
th
i
s
is
p
ar
tiall
y
p
o
s
s
ib
le
w
ith
t
h
e
u
s
e
o
f
a
p
p
licatio
n
s
li
k
e
S
k
y
p
e
an
d
Face
T
im
e
b
y
A
p
p
le,
w
h
er
e
t
w
o
p
eo
p
le
ca
n
tal
k
to
ea
ch
o
t
h
er
th
r
o
u
g
h
a
ca
m
er
a
an
d
s
cr
ee
n
.
T
o
im
p
r
o
v
e
o
u
r
ab
ilit
y
to
co
m
m
u
n
icate
w
it
h
o
th
er
s
i
n
o
t
h
er
p
ar
ts
o
f
th
e
g
lo
b
e,
s
cien
ti
s
ts
ar
e
co
n
tin
u
i
n
g
to
r
esear
ch
m
et
h
o
d
s
th
at
in
co
r
p
o
r
ate
v
ir
tu
a
l r
ea
lit
y
i
n
to
telec
o
m
m
u
n
icatio
n
s
.
Fo
r
ex
a
m
p
le,
a
g
r
o
u
p
o
f
s
t
u
d
en
ts
f
r
o
m
Osa
k
a
Un
i
v
e
r
s
it
y
in
J
ap
an
cr
ea
ted
a
m
ac
h
i
n
e
t
h
at
t
w
o
u
s
er
s
ca
n
u
s
e
to
t
elec
o
n
f
er
e
n
ce
ea
c
h
o
th
er
an
d
to
s
h
a
k
e
a
r
o
b
o
tic
h
an
d
[
2
0
]
.
W
h
en
th
e
y
s
h
a
k
e
th
e
h
a
n
d
,
it
r
ep
licates
t
h
e
te
x
tu
r
e,
s
tr
en
g
t
h
,
an
d
w
ar
m
t
h
o
f
t
h
e
o
t
h
er
u
s
er
’
s
h
a
n
d
.
I
t
m
ak
e
s
t
h
e
m
f
ee
l
as
if
t
h
e
y
b
o
th
w
er
e
t
h
er
e.
T
h
is
m
a
k
es
it
p
o
s
s
ib
le
f
o
r
p
eo
p
le
o
n
o
th
er
s
id
es
o
f
th
e
wo
r
ld
ab
le
to
m
ee
t
an
d
d
is
cu
s
s
b
u
s
i
n
ess
o
r
j
u
s
t
h
av
e
a
ca
s
u
al
g
r
ee
tin
g
w
it
h
ea
c
h
o
th
er
.
W
ith
all
t
h
e
s
e
ad
v
an
ce
m
e
n
ts
in
v
ir
t
u
al
r
ea
lit
y
,
w
e
h
a
v
e
m
a
d
e
lar
g
e
leap
s
in
en
ter
tain
m
e
n
t
a
n
d
f
u
n
ac
tiv
itie
s
.
A
s
w
ith
th
e
ad
v
an
ce
s
in
s
p
o
r
ts
,
g
i
v
i
n
g
p
eo
p
le
f
ee
lin
g
s
a
n
d
ex
p
er
ien
ce
s
t
h
e
y
m
a
y
n
e
v
er
h
a
v
e
o
r
p
o
s
s
ib
l
y
co
u
ld
h
av
e
i
s
t
h
e
g
o
a
l
f
o
r
s
o
m
e
s
cien
tis
t.
As
n
o
ted
a
b
o
v
e,
s
i
m
u
lato
r
s
f
o
r
th
e
p
u
b
l
ic
allo
w
p
eo
p
le
to
f
l
y
j
ets
o
r
o
th
er
a
ir
cr
af
t,
r
id
e
r
o
ller
co
aster
s
w
it
h
o
u
t
b
ein
g
th
er
e,
an
d
e
v
e
n
v
e
n
tu
r
e
th
e
wo
r
ld
.
Fo
r
ex
a
m
p
le,
w
it
h
3
D
m
o
v
ie
s
an
d
I
MA
X
f
il
m
s
v
ie
w
er
s
f
ee
l
li
k
e
th
e
y
ar
e
i
n
th
e
m
o
v
ie
an
d
a
p
ar
t o
f
th
e
f
il
m
.
T
h
r
o
u
g
h
th
ese
tech
n
o
lo
g
ies,
d
o
cu
m
e
n
tar
ies
c
an
m
ak
e
p
eo
p
le
f
ee
l
li
k
e
t
h
e
y
ar
e
in
w
h
atev
er
ar
ea
t
h
e
y
ar
e
w
atc
h
i
n
g
,
a
s
i
f
t
h
e
y
ar
e
f
o
llo
w
in
g
th
e
f
i
l
m
cr
e
w
.
I
n
t
h
e
ea
r
l
y
1
9
9
0
s
,
Nin
te
n
d
o
cr
ea
ted
th
e
V
ir
tu
al
B
o
y
s
y
s
te
m
,
w
h
ic
h
w
a
s
a
s
et
o
f
g
o
g
g
les
o
n
a
s
ta
n
d
th
e
u
s
e
r
lo
o
k
ed
in
to
an
d
p
la
y
ed
g
a
m
es
o
n
.
Un
f
o
r
tu
n
atel
y
,
t
h
e
s
y
s
te
m
w
a
s
b
ad
l
y
r
ev
ie
w
ed
an
d
w
as
n
o
t
ea
s
y
to
p
la
y
.
E
v
e
n
t
h
o
u
g
h
it
w
as
n
o
t
co
n
s
id
er
e
d
a
g
o
o
d
g
a
m
e
s
y
s
te
m
,
it
led
to
th
e
r
e
s
ea
r
ch
a
n
d
d
ev
elo
p
m
en
t o
f
n
e
w
v
ir
t
u
al
r
ea
lit
y
g
a
m
e
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2088
-
8708
V
ir
tu
a
l Ma
in
ten
a
n
ce
,
R
e
a
lity,
a
n
d
S
ystems
:
A
R
ev
iew
(
K
o
u
r
o
u
s
h
Je
n
a
b
)
2701
2.
2
.
Civ
il Av
i
a
t
io
n
Uses
Vir
tu
al
R
ea
lit
y
o
r
v
ir
tu
al
m
a
in
te
n
an
ce
s
y
s
te
m
s
ar
e
co
m
p
u
ter
-
g
e
n
er
ated
en
v
ir
o
n
m
en
ts
t
h
at
ca
n
b
e
in
ter
ac
ted
w
it
h
a
n
d
ar
e
u
s
ed
f
o
r
tr
ain
i
n
g
p
u
r
p
o
s
es
o
r
i
n
s
p
e
ctio
n
s
.
Vir
tu
al
R
ea
lit
y
is
u
s
ed
in
m
a
n
y
d
i
f
f
er
en
t
f
ield
s
s
u
ch
as
m
ed
ical,
m
i
litar
y
,
r
esear
ch
p
u
r
p
o
s
es,
a
n
d
t
h
e
a
v
iatio
n
i
n
d
u
s
tr
y
.
T
h
e
Air
Fo
r
ce
is
a
b
r
an
ch
o
f
t
h
e
m
ilit
ar
y
w
h
er
e
v
ir
t
u
al
r
ea
lit
y
h
as
b
ee
n
u
s
ed
g
r
ea
tl
y
to
h
elp
tr
ain
p
ilo
ts
q
u
ic
k
l
y
an
d
e
f
f
icie
n
tl
y
.
Vir
tu
al
r
ea
li
t
y
is
w
id
el
y
u
s
ed
b
y
m
il
itar
y
an
d
co
m
m
er
cial
air
li
n
e
s
f
o
r
air
cr
af
t
in
s
p
ec
tio
n
to
en
s
u
r
e
th
a
t e
v
er
y
th
i
n
g
i
s
w
o
r
k
in
g
p
r
o
p
er
ly
an
d
to
m
a
k
e
s
u
r
e
th
e
air
cr
af
t
is
s
a
f
e
f
o
r
f
li
g
h
t.
V
ir
tu
al
r
ea
lit
y
is
u
s
ed
to
tr
ain
p
ilo
ts
in
a
r
ea
lis
tic
en
v
ir
o
n
m
e
n
t
s
o
t
h
e
y
ca
n
ex
p
er
ien
ce
d
if
f
er
en
t
f
li
g
h
t
co
n
d
it
io
n
s
,
b
u
t
w
it
h
i
n
a
s
a
f
e
en
v
ir
o
n
m
e
n
t
[
3
6
]
.
Vir
tu
al
r
ea
lit
y
s
i
m
u
lat
io
n
allo
w
s
m
ili
tar
y
p
er
s
o
n
n
el
to
ex
p
er
ie
n
ce
d
an
g
er
o
u
s
s
it
u
atio
n
s
a
n
d
lear
n
h
o
w
to
ad
ap
t
to
d
if
f
er
e
n
t
s
ce
n
ar
io
s
,
b
u
t
w
i
th
o
u
t
t
h
e
r
i
s
k
o
f
d
ea
t
h
o
r
i
n
j
u
r
y
[
3
6
]
.
T
h
e
Av
iatio
n
I
n
d
u
s
tr
y
r
eq
u
ir
es
m
an
d
ato
r
y
tr
ain
i
n
g
th
r
o
u
g
h
o
u
t
th
e
ca
r
ee
r
o
f
ev
e
r
y
o
n
e
in
v
o
l
v
ed
.
C
o
m
m
er
cial
air
li
n
es
an
d
th
e
m
ilit
ar
y
h
a
v
e
b
o
t
h
b
ee
n
u
s
i
n
g
v
ir
tu
al
s
i
m
u
latio
n
s
f
o
r
m
o
r
e
th
a
n
s
e
v
e
n
t
y
y
ea
r
s
to
tr
ain
n
e
w
p
ilo
ts
[
3
6
]
.
I
n
o
r
d
er
to
k
ee
p
u
p
w
it
h
t
h
e
m
o
s
t r
ec
e
n
t
m
eth
o
d
s
a
n
d
g
u
id
elin
es,
tr
ai
n
i
n
g
is
a
m
u
s
t.
Vir
t
u
al
tr
ai
n
in
g
h
as c
o
m
e
a
lo
n
g
w
a
y
a
n
d
co
n
ti
n
u
e
s
to
b
e
an
ess
e
n
tial p
ar
t in
b
r
in
g
i
n
g
m
u
c
h
s
u
cc
ess
to
t
h
e
av
ia
tio
n
in
d
u
s
tr
y
.
T
h
er
e
ar
e
s
ev
er
al
d
i
f
f
er
e
n
t
u
s
es
o
f
v
ir
t
u
al
r
ea
li
t
y
in
t
h
e
a
v
i
atio
n
i
n
d
u
s
tr
y
.
T
h
e
m
o
s
t
n
o
te
d
u
s
e
f
o
r
v
ir
tu
a
l
r
ea
lit
y
i
s
tr
ai
n
i
n
g
p
ilo
t
s
an
d
air
cr
af
t
in
s
p
ec
tio
n
s
.
A
ir
cr
af
t
i
n
s
p
ec
tio
n
s
a
n
d
m
ai
n
te
n
an
ce
ar
e
a
n
e
s
s
e
n
tial
p
ar
t
o
f
s
af
e
a
n
d
r
eliab
le
tr
an
s
p
o
r
tatio
n
.
T
r
ain
in
g
h
a
s
b
ee
n
i
d
en
tifie
d
as
th
e
p
r
i
m
ar
y
i
n
ter
v
en
t
io
n
s
tr
ate
g
y
in
i
m
p
r
o
v
i
n
g
i
n
s
p
ec
tio
n
p
er
f
o
r
m
an
ce
.
Air
cr
af
t
m
a
in
te
n
a
n
ce
is
a
f
ac
to
r
th
at
s
h
o
u
ld
b
e
at
th
e
to
p
o
f
th
e
lis
t
an
d
th
e
tr
ain
i
n
g
f
o
r
air
cr
af
t
m
a
in
t
en
an
ce
i
s
n
e
v
er
-
e
n
d
in
g
.
Vir
tu
al
air
cr
af
t
m
ai
n
te
n
an
ce
tr
ai
n
in
g
h
as
m
ad
e
it
m
u
c
h
ea
s
ier
f
o
r
th
e
tr
ain
ee
s
to
g
r
asp
a
s
tr
o
n
g
h
o
ld
o
f
th
e
co
n
ce
p
ts
o
f
air
cr
af
t
m
ai
n
te
n
an
ce
.
Vis
u
al
in
s
p
ec
tio
n
s
k
i
ll
s
ca
n
b
e
tau
g
h
t
e
f
f
ec
ti
v
el
y
u
s
in
g
r
ep
r
esen
tati
v
e
p
h
o
to
g
r
ap
h
ic
i
m
a
g
es
s
h
o
w
i
n
g
a
w
id
e
r
an
g
e
o
f
co
n
d
itio
n
s
w
i
t
h
i
m
m
ed
iate
f
ee
d
b
ac
k
o
n
t
h
e
t
r
ain
ee
’
s
d
ec
is
io
n
i
n
a
co
n
tr
o
lled
en
v
ir
o
n
m
e
n
t.
I
n
s
p
ec
tio
n
i
s
r
eg
u
lated
b
y
th
e
Fed
er
al
A
v
iatio
n
A
d
m
in
is
tr
at
io
n
(
FAA
)
,
as
i
s
m
ai
n
t
e
n
an
c
e.
T
h
er
e
ar
e
o
r
g
an
izatio
n
s
o
u
t
th
er
e
t
h
at
s
o
lel
y
d
ev
elo
p
v
ir
tu
al
tr
ai
n
er
s
to
h
elp
en
s
u
r
e
s
af
et
y
.
A
er
o
s
i
m
T
ec
h
n
o
lo
g
ies
h
a
s
d
e
v
elo
p
ed
v
ir
t
u
al
m
ai
n
te
n
an
ce
t
r
ain
er
s
f
o
r
s
e
v
er
al
d
i
f
f
er
e
n
t
ai
r
cr
af
ts
.
An
ex
a
m
p
le
o
f
o
n
e
air
cr
af
t
t
y
p
e
is
th
e
B
o
ein
g
7
3
7
NG.
T
h
e
Vir
t
u
al
Ma
i
n
te
n
an
ce
T
r
ain
er
™
is
a
s
i
m
u
latio
n
-
b
ased
tr
ain
i
n
g
d
ev
ice
d
esig
n
ed
to
o
p
tim
ize
tr
ain
i
n
g
ti
m
e
an
d
i
m
p
r
o
v
e
th
e
lear
n
i
n
g
p
r
o
ce
s
s
f
o
r
m
ai
n
ten
a
n
c
e
p
er
s
o
n
n
el.
T
h
e
Vir
t
u
al
Fli
g
h
t
Dec
k
(
VF
D)
an
d
t
h
e
Vir
t
u
al
Air
cr
af
t
(
V
A
)
ar
e
co
m
b
i
n
ed
f
o
r
tr
ain
i
n
g
o
n
co
m
p
o
n
e
n
t
lo
ca
tio
n
,
s
y
s
te
m
lo
g
ic/o
p
er
atio
n
,
tr
o
u
b
les
h
o
o
tin
g
,
f
au
lt
i
s
o
latio
n
p
r
o
ce
d
u
r
es,
an
d
r
etu
r
n
-
to
-
s
er
v
ic
e
test
s
.
T
h
e
Vir
t
u
al
Fli
g
h
t
Dec
k
(
VFD)
is
a
f
u
ll
s
i
m
u
latio
n
o
f
y
o
u
r
air
cr
af
t
’
s
s
p
ec
i
f
ic
f
lig
h
t
d
ec
k
b
r
o
u
g
h
t
to
li
f
e
o
n
a
P
C
.
W
ith
th
e
VFD,
m
ai
n
ten
a
n
ce
tec
h
n
ic
ian
tr
ain
ee
s
ca
n
s
ca
n
,
v
ie
w
a
n
d
o
p
er
ate
a
ll
p
an
els,
co
n
tr
o
ls
,
in
d
icato
r
s
an
d
d
is
p
la
y
s
w
i
th
in
th
e
f
li
g
h
t
d
ec
k
.
Vir
t
u
al
A
ir
cr
af
t
(
V
A
)
en
ab
le
s
tec
h
n
icia
n
s
t
o
p
er
f
o
r
m
e
x
ter
n
al
co
m
p
o
n
e
n
t
lo
ca
tio
n
,
w
al
k
ar
o
u
n
d
i
n
s
p
ec
tio
n
a
n
d
p
r
o
ce
d
u
r
e
b
ased
in
ter
ac
tio
n
.
U
s
er
s
a
r
e
ab
le
to
p
er
f
o
r
m
p
r
ac
tical
ex
er
cise
s
to
i
n
cl
u
d
e
o
p
er
atio
n
al
test
s
(
s
y
s
te
m
s
an
d
B
I
T
E
)
,
A
MM
&
T
SM/FIM
tas
k
s
,
M
ME
L
m
ai
n
ten
a
n
ce
p
r
o
ce
d
u
r
es,
an
d
s
er
v
ici
n
g
.
A
cti
v
e
S
y
s
te
m
S
ch
e
m
a
tics
ar
e
d
etailed
d
iag
r
a
m
s
o
f
t
h
e
air
cr
af
t
s
y
s
te
m
s
.
T
h
e
y
s
h
o
w
in
r
ea
l
-
ti
m
e
w
h
a
t
is
h
ap
p
en
in
g
w
it
h
i
n
th
e
air
cr
af
t
s
y
s
te
m
s
b
ased
o
n
f
li
g
h
t
d
ec
k
in
p
u
ts
.
T
h
ese
A
ct
iv
e
S
y
s
te
m
Sc
h
e
m
a
tics
ar
e
tied
d
ir
ec
tl
y
i
n
to
t
h
e
s
i
m
u
latio
n
in
p
r
o
g
r
es
s
.
W
ith
t
h
e
ad
v
a
n
ce
m
e
n
t
o
f
th
e
a
v
iatio
n
i
n
d
u
s
tr
y
a
n
d
all
t
h
e
ab
ilit
ie
s
t
h
at
th
e
air
cr
af
t
s
a
r
e
n
o
w
ab
le
to
p
er
f
o
r
m
,
m
ain
t
en
an
ce
is
o
n
e
o
f
t
h
e
m
o
s
t i
m
p
o
r
tan
t a
s
p
ec
ts
i
n
t
h
e
i
n
d
u
s
tr
y
.
On
ce
m
a
in
te
n
a
n
ce
an
d
in
s
p
ec
tio
n
s
ar
e
p
er
f
o
r
m
ed
o
n
th
e
ai
r
cr
af
t,
th
e
n
e
x
t
i
m
p
o
r
ta
n
t
asp
ec
t
in
th
e
av
iatio
n
i
n
d
u
s
tr
y
is
en
s
u
r
i
n
g
th
at
a
ll
p
ilo
ts
ar
e
p
r
o
p
er
ly
tr
ain
ed
to
h
a
n
d
le
t
h
e
air
cr
a
f
t
a
n
d
d
if
f
er
e
n
t
f
li
g
h
t
co
n
d
itio
n
s
th
e
y
m
a
y
f
ac
e.
P
ilo
ts
h
av
e
to
m
ee
t
s
p
ec
ial
F
AA
r
eq
u
ir
e
m
e
n
t
s
to
o
b
tai
n
a
co
m
m
er
cial
p
ilo
t
ce
r
tif
icatio
n
.
I
n
o
r
d
er
to
o
b
tain
a
co
m
m
er
cial
p
ilo
t
ce
r
tif
icat
io
n
i
n
th
e
US,
t
h
er
e
ar
e
s
ev
er
al
b
asic
r
eq
u
ir
e
m
en
ts
.
On
ce
t
h
e
b
asic
r
eq
u
ir
em
e
n
t
s
ar
e
m
e
t,
f
u
tu
r
e
p
ilo
ts
w
ill
g
o
t
h
r
o
u
g
h
s
e
v
er
al
ar
ea
s
o
f
test
in
g
(
FAA
.
Or
g
)
.
Si
m
u
latio
n
-
b
ased
lear
n
in
g
h
as
b
ee
n
w
id
el
y
u
s
ed
i
n
th
e
a
v
iatio
n
i
n
d
u
s
tr
y
f
o
r
m
an
y
y
ea
r
s
(
v
r
s
.
g
o
v
)
.
A
ir
cr
af
t
s
i
m
u
lato
r
s
o
r
f
lig
h
t
s
i
m
u
lato
r
s
tr
y
to
r
ep
licate
th
e
ex
p
er
ien
ce
o
f
f
l
y
i
n
g
a
n
air
cr
af
t.
Si
m
u
lato
r
s
ca
n
b
e
s
i
m
p
le
co
m
p
u
ter
g
a
m
es
o
r
th
e
ex
ac
t
r
ep
lica
o
f
a
co
ck
p
it
o
n
h
y
d
r
a
u
lic
a
ctu
ato
r
s
w
it
h
h
i
g
h
l
y
ad
v
an
ce
d
tec
h
n
o
lo
g
y
.
Si
m
u
la
to
r
s
ar
e
u
s
ed
b
y
t
h
e
A
r
m
y
,
N
av
y
,
A
ir
Fo
r
ce
,
a
n
d
co
m
m
er
c
ial
air
li
n
es
to
tr
ain
p
ilo
ts
.
Fli
g
h
t
s
i
m
u
lato
r
s
h
elp
p
ilo
ts
d
ev
elo
p
n
e
w
s
k
ill
s
in
h
an
d
li
n
g
t
h
e
air
cr
af
t
u
n
d
er
u
n
u
s
u
al
co
n
d
itio
n
s
.
T
h
er
e
ar
e
m
an
y
d
if
f
er
e
n
ce
t
y
p
es
o
f
s
i
m
u
la
to
r
s
th
at
ar
e
w
id
el
y
u
s
ed
in
t
h
e
av
ia
tio
n
i
n
d
u
s
t
r
y
.
C
A
E
i
s
a
g
lo
b
al
lead
er
in
p
r
o
v
id
in
g
co
m
p
r
eh
en
s
i
v
e
tr
ai
n
i
n
g
s
o
l
u
tio
n
s
b
as
ed
o
n
w
o
r
ld
-
lead
in
g
s
i
m
u
lati
o
n
tech
n
o
lo
g
y
a
n
d
in
te
g
r
ated
tr
ain
in
g
s
er
v
ices.
T
h
e
y
ar
e
th
e
in
d
u
s
tr
y
’
s
f
ir
s
t
F
AA
-
ap
p
r
o
v
ed
w
eb
-
b
ased
Vir
t
u
al
Gr
o
u
n
d
Sc
h
o
o
l
f
o
r
b
u
s
i
n
es
s
air
cr
af
t
p
ilo
t
r
ec
u
r
r
en
t
tr
ai
n
i
n
g
.
T
h
e
y
o
f
f
er
e
-
L
ea
r
n
i
n
g
w
it
h
m
o
r
e
th
a
n
5
,
0
0
0
h
o
u
r
s
o
f
o
n
li
n
e
co
u
r
s
es,
i
n
cl
u
d
in
g
g
e
n
er
al
o
p
er
atin
g
s
u
b
j
ec
ts
,
b
asic
a
v
iatio
n
s
tu
d
ie
s
,
air
cr
af
t
t
y
p
e
-
s
p
ec
if
i
c,
an
d
m
ai
n
ten
a
n
c
e
tr
ain
i
n
g
co
u
r
s
e
s
.
C
A
E
e
-
L
ea
r
n
in
g
p
r
o
g
r
a
m
s
ar
e
av
ailab
le
an
y
w
h
er
e
an
y
ti
m
e.
T
h
er
e
ar
e
m
an
y
co
m
p
a
n
ies
li
k
e
C
A
E
th
at
h
elp
th
e
e
v
er
y
d
a
y
p
ilo
t
k
ee
p
u
p
-
to
-
d
ate
w
ith
t
h
e
l
atest
tr
ain
i
n
g
m
et
h
o
d
s
o
n
li
n
e
t
h
at
g
r
ea
tl
y
r
ed
u
ce
s
co
s
ts
.
A
ir
Fo
r
ce
p
ilo
ts
g
o
t
h
r
o
u
g
h
r
ig
o
r
o
u
s
tr
ai
n
i
n
g
i
n
s
tal
l
m
e
n
t
s
t
o
b
e
th
e
b
est
o
f
th
e
b
est
a
t
w
h
at
th
e
y
d
o
.
A
k
e
y
f
ac
to
r
i
n
th
e
tr
ai
n
in
g
f
o
r
Air
Fo
r
ce
p
ilo
ts
is
t
h
at
o
f
f
li
g
h
t
s
i
m
u
lato
r
s
.
P
ilo
ts
i
n
t
h
e
Air
Fo
r
ce
to
d
a
y
ar
e
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
,
Decem
b
er
201
6
:
2
6
9
8
–
2
7
0
7
2702
n
o
w
ab
le
to
r
el
y
o
n
v
ir
t
u
al
r
e
alit
y
tr
ai
n
i
n
g
m
et
h
o
d
s
to
i
m
p
r
o
v
e
th
eir
s
k
i
lls
.
T
h
e
A
ir
Fo
r
ce
u
s
e
s
v
ir
tu
al
r
ea
lit
y
as
p
ar
t
o
f
th
eir
tr
ai
n
in
g
s
y
s
te
m
s
.
T
h
e
m
o
s
t
w
ell
-
k
n
o
w
n
u
s
e
ar
e
f
lig
h
t
s
i
m
u
la
to
r
s
w
h
ic
h
ar
e
d
esig
n
ed
to
teac
h
f
l
y
in
g
s
k
ills
b
u
t
w
it
h
i
n
a
s
af
e
en
v
ir
o
n
m
en
t.
Si
m
u
lato
r
s
ar
e
u
s
ed
to
tr
ai
n
m
i
litar
y
p
ilo
ts
f
o
r
co
m
b
at
m
i
s
s
io
n
s
an
d
ai
m
to
allo
w
t
h
e
p
ilo
ts
to
f
ee
l
a
s
e
n
s
e
o
f
i
m
m
er
s
io
n
an
d
to
f
ee
l
as
i
f
t
h
e
y
ar
e
f
l
y
i
n
g
a
r
ea
l
air
cr
af
t,
b
u
t
w
it
h
o
u
t
t
h
e
d
an
g
er
s
o
f
f
l
y
in
g
a
r
ea
l
air
cr
af
t
i
n
a
co
m
b
at
zo
n
e.
Si
m
u
lato
r
s
ar
e
p
r
o
g
r
am
m
ed
to
m
i
m
ic
t
h
e
m
o
v
e
m
e
n
ts
o
f
a
r
ea
l
a
ir
cr
af
t
an
d
p
r
o
v
id
e
f
ee
d
b
ac
k
to
th
e
p
ilo
t.
R
ea
lit
y
Me
d
ia
i
s
a
p
r
i
v
ate
co
m
p
a
n
y
t
h
at
s
p
ec
ialize
s
in
t
h
e
d
esig
n
,
d
ev
elo
p
m
e
n
t,
an
d
p
r
o
d
u
ctio
n
o
f
s
tate
-
of
-
t
h
e
-
ar
t
s
i
m
u
lato
r
s
,
as
w
el
l
as
tr
ain
i
n
g
s
y
s
te
m
s
[
1
0
0
]
.
Vir
tu
al
R
ea
lit
y
Me
d
ia’
s
Mi
-
1
7
1
f
u
l
l
f
li
g
h
t
/
f
u
ll
m
i
s
s
io
n
s
i
m
u
lato
r
p
r
o
v
id
es
all
t
h
e
eq
u
ip
m
en
t
an
d
s
o
f
t
w
ar
e
s
u
p
p
o
r
t
n
ec
ess
a
r
y
f
o
r
g
r
o
u
n
d
an
d
f
li
g
h
t
o
p
er
atio
n
s
tr
ain
i
n
g
[
1
0
0
]
.
T
h
e
s
ix
d
eg
r
ee
o
f
f
r
ee
d
o
m
(
s
ix
Do
F)
m
o
t
io
n
p
lat
f
o
r
m
,
r
ea
lis
tic
co
n
tr
o
l
lo
ad
in
g
s
y
s
t
e
m
(
C
L
S)
a
n
d
v
ib
r
atin
g
s
ea
t
s
cr
ea
te
a
r
ea
lis
tic
tr
ain
i
n
g
e
x
p
er
ien
ce
[
1
0
0
]
.
Fu
ll
-
f
li
g
h
t
s
i
m
u
lato
r
s
ar
e
t
h
e
m
o
s
t
ca
p
ab
le
a
v
iatio
n
tr
ain
i
n
g
d
ev
ic
es.
F
u
ll
-
f
li
g
h
t
s
i
m
u
lato
r
s
r
ep
licate
air
cr
af
t
ch
ar
ac
ter
is
tic
s
w
it
h
a
h
ig
h
le
v
el
o
f
f
id
elit
y
an
d
h
elp
th
e
p
ilo
t
tr
ain
ee
ex
p
er
ien
ce
d
if
f
er
en
t
co
n
d
itio
n
s
th
e
y
m
a
y
e
n
co
u
n
ter
d
u
r
in
g
f
l
ig
h
t.
Fu
ll
-
Fli
g
h
t
s
i
m
u
lato
r
s
h
av
e
b
o
th
v
is
u
al
an
d
m
o
tio
n
ca
p
ab
ilit
ies
an
d
ar
e
in
cr
ed
ib
l
y
ac
cu
r
ate
i
n
allo
w
i
n
g
t
h
e
p
ilo
t
to
ex
p
er
ien
ce
ex
ac
tl
y
w
h
at
f
l
y
i
n
g
th
e
air
cr
af
t
w
o
u
ld
b
e
lik
e.
As
s
h
o
w
n
in
F
ig
u
r
e
1
,
th
e
f
li
g
h
t
tr
ain
in
g
d
ev
ice
s
ar
e
d
if
f
er
e
n
t
f
r
o
m
f
u
ll
f
li
g
h
t
s
i
m
u
lato
r
s
i
n
th
at
t
h
e
y
ar
e
n
o
t
al
w
a
y
s
m
o
tio
n
ca
p
ab
le,
b
u
t a
r
e
s
o
p
h
is
t
icate
d
en
o
u
g
h
to
p
r
o
v
id
e
tr
ain
in
g
f
o
r
p
ilo
ts
.
Fig
u
r
e
1
.
C
o
m
p
leted
DC
-
9
Fli
g
h
t
Si
m
u
la
to
r
C
o
ck
p
it
Vir
tu
al
r
ea
lit
y
i
s
u
s
ed
to
tr
ain
m
ilit
ar
y
p
ilo
ts
to
ev
ac
u
ate
t
h
e
air
cr
af
t
in
e
m
er
g
en
c
y
s
it
u
atio
n
s
.
W
h
e
n
f
o
r
ce
d
to
ev
ac
u
ate
a
n
air
cr
af
t
m
id
-
f
li
g
h
t,
it
is
d
if
f
ic
u
lt
to
th
i
n
k
ab
o
u
t
w
h
at
co
u
r
s
e
o
f
ac
tio
n
s
h
o
u
ld
b
e
tak
e
n
to
en
s
u
r
e
s
u
r
v
i
v
al.
A
d
ev
ice
ca
lled
th
e
V
ir
tu
al
R
ea
li
t
y
Han
g
in
g
Har
n
es
s
T
r
ain
er
is
u
s
ed
to
g
i
v
e
p
ilo
ts
th
e
ex
p
er
ien
ce
o
f
e
m
er
g
e
n
c
y
p
ar
ac
h
u
t
in
g
o
u
t
o
f
an
air
cr
af
t.
T
h
e
s
i
m
u
la
to
r
allo
w
s
p
ilo
ts
to
ex
p
er
ien
ce
th
e
f
ee
l
o
f
a
4
0
0
0
-
f
o
o
t
j
u
m
p
w
h
ile
u
s
i
n
g
a
co
m
p
u
ter
s
y
s
te
m
to
p
r
o
d
u
ce
d
if
f
er
e
n
t
s
ce
n
ar
io
s
,
s
u
c
h
as
w
i
n
d
co
n
d
itio
n
s
,
co
m
b
at
zo
n
es,
a
n
d
v
ar
y
i
n
g
te
r
r
ain
s
.
P
ar
ac
h
u
te
i
n
s
tr
u
cto
r
s
w
il
l
b
e
ab
le
to
s
i
m
u
late
s
i
tu
a
tio
n
s
w
h
er
e
a
j
u
m
p
g
o
es
w
r
o
n
g
,
m
o
n
ito
r
a
s
tu
d
en
t's
p
er
f
o
r
m
an
ce
,
an
d
p
r
o
v
id
e
f
ee
d
b
ac
k
u
s
in
g
d
ig
ital
v
id
eo
r
ec
o
r
d
in
g
s
.
“
W
h
ils
t
th
e
tr
ain
er
w
il
l
n
o
t
r
ep
lace
li
v
e
d
escen
t
s
f
o
r
t
h
e
tr
ain
ee
p
a
r
ac
h
u
ti
s
ts
,
t
h
e
o
p
p
o
r
tu
n
it
y
to
r
ep
ea
ted
ly
p
r
ac
tice
d
r
ills
an
d
r
ea
ct
to
e
m
er
g
en
c
y
s
itu
a
tio
n
s
in
a
s
a
f
e
an
d
,
i
m
p
o
r
tan
tl
y
,
r
ea
lis
tic
v
ir
t
u
al
e
n
v
ir
o
n
m
en
t,
is
i
n
v
alu
ab
le
an
d
w
ill g
r
ea
tl
y
e
n
h
a
n
ce
tr
ain
i
n
g
d
eli
v
er
y
a
n
d
u
lti
m
atel
y
s
a
f
et
y
(
h
ttp
:/
/
www
.
r
af
.
m
o
d
.
u
k
/n
e
w
s
/ar
ch
i
v
e)
.
”
No
m
atter
h
o
w
s
k
il
led
a
p
ilo
t
m
i
g
h
t
b
e,
tr
ain
i
n
g
w
il
l
al
w
a
y
s
b
e
n
ev
er
-
e
n
d
in
g
.
T
h
er
e
ar
e
al
w
a
y
s
n
e
w
m
et
h
o
d
s
an
d
ad
v
an
ce
d
tec
h
n
o
lo
g
y
co
m
i
n
g
o
u
t
to
b
etter
as
s
is
t in
s
a
f
et
y
.
Si
m
u
lato
r
s
ar
e
g
ett
in
g
m
o
r
e
a
n
d
m
o
r
e
ad
v
an
ce
d
w
it
h
t
h
e
n
e
v
er
-
e
n
d
i
n
g
ad
v
a
n
ce
s
i
n
tec
h
n
o
lo
g
y
.
T
h
e
w
o
r
ld
o
f
v
ir
t
u
al
r
ea
lit
y
h
as
m
ad
e
it
m
u
ch
ea
s
ier
f
o
r
th
e
p
ilo
t
to
tr
ain
in
r
ea
l
-
wo
r
ld
clim
ate
s
w
it
h
r
ed
u
ce
d
r
is
k
.
Vir
tu
al
r
ea
lit
y
allo
w
s
f
o
r
p
ilo
ts
to
r
em
a
in
w
el
l
-
tr
ain
ed
an
d
u
p
-
to
-
d
ate
o
n
n
e
w
f
li
g
h
t
r
eq
u
ir
e
m
e
n
ts
.
Mo
s
t
p
ilo
ts
w
i
ll
ag
r
ee
t
h
at
f
lig
h
t
s
i
m
u
lat
io
n
is
t
h
e
q
u
ick
e
s
t,
ea
s
iest
,
an
d
m
o
s
t
co
s
t
ef
f
ic
ien
t
r
o
u
te
f
o
r
lear
n
i
n
g
to
o
p
er
ate
an
air
cr
af
t.
I
f
it
w
er
e
n
o
t
f
o
r
v
ir
t
u
al
tr
ain
i
n
g
,
w
e
w
o
u
ld
n
o
t.
3
.
CO
NCLU
SI
O
N
W
e
ex
p
ec
t
en
d
-
to
-
e
n
d
v
i
r
t
u
ali
za
tio
n
to
b
ec
o
m
e
a
n
o
r
m
a
l
p
ar
t
o
f
f
u
t
u
r
e
tr
ain
i
n
g
en
v
ir
o
n
m
en
ts
.
I
t
is
n
o
te
w
o
r
t
h
y
t
h
at
p
r
o
v
id
in
g
a
v
ir
tu
aliza
t
io
n
tr
ain
i
n
g
la
y
e
r
ca
n
n
o
t
g
u
ar
a
n
tee
th
e
e
f
f
e
ctiv
e
tr
ain
i
n
g
f
o
r
m
ai
n
ten
a
n
ce
cr
e
w
a
n
d
p
ilo
ts
.
T
h
e
f
lex
ib
ilit
y
t
h
at
m
ak
e
s
v
ir
tu
al
r
ea
lit
y
a
n
ef
f
ec
ti
v
e
to
o
l
s
h
o
u
ld
h
a
v
e
b
ee
n
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2088
-
8708
V
ir
tu
a
l Ma
in
ten
a
n
ce
,
R
e
a
lity,
a
n
d
S
ystems
:
A
R
ev
iew
(
K
o
u
r
o
u
s
h
Je
n
a
b
)
2703
co
n
s
id
er
ed
in
f
u
t
u
r
e
d
ev
elo
p
m
en
t
o
f
in
f
r
as
tr
u
ct
u
r
es.
C
u
r
r
en
t
li
ter
atu
r
e
r
elate
d
to
v
ir
t
u
a
l
r
ea
lit
y
an
d
v
ir
t
u
al
m
ai
n
ten
a
n
ce
h
as
f
o
cu
s
ed
lar
g
el
y
o
n
t
h
e
i
m
p
le
m
en
ta
tio
n
o
f
v
ir
t
u
aliza
t
io
n
a
n
d
its
ap
p
l
icatio
n
s
.
T
h
er
ef
o
r
e,
f
u
r
t
h
er
att
en
t
io
n
is
d
u
e
to
th
e
s
ec
u
r
it
y
r
is
k
s
,
r
eq
u
ir
ed
tech
n
o
lo
g
y
f
o
r
d
ev
elo
p
in
g
in
f
r
astru
ct
u
r
e
to
m
ee
t
ch
alle
n
g
e
s
in
v
ir
t
u
al
m
a
in
te
n
a
n
ce
tr
ain
i
n
g
.
RE
F
E
R
E
NC
E
S
[1
]
Am
b
a
n
i,
S
.
,
M
e
e
rk
o
v
,
S
.
M
.
,
&
L
ian
g
,
Z.
(2
0
1
0
).
F
e
a
sib
il
it
y
a
n
d
o
p
ti
m
iza
ti
o
n
o
f
p
re
v
e
n
ti
v
e
m
a
in
ten
a
n
c
e
in
e
x
p
o
n
e
n
ti
a
l
m
a
c
h
in
e
s an
d
se
rial
li
n
e
s.
IIE
T
r
a
n
sa
c
ti
o
n
s
,
4
2
(1
0
),
7
6
6
-
7
7
7
.
d
o
i:
1
0
.
1
0
8
0
/
0
7
4
0
8
1
7
1
0
0
3
7
4
9
2
0
9
.
[2
]
A
n
d
re
,
T
.
S
.
,
Be
n
n
e
tt
,
W
.
R.
,
Ca
st
il
lo
,
A
.
R.
,
M
c
Clain
,
D.
P
.
,
P
u
rtee
,
M
.
D.,
W
e
n
z
e
l,
B.
M
.
,
a
n
d
G
ra
c
i
.
M
.
(2
0
0
3
).
G
e
n
e
r
a
li
z
e
d
o
p
e
ra
ti
o
n
s
sim
u
latio
n
e
n
v
iro
n
m
e
n
t
f
o
r
a
ircra
f
t
m
a
i
n
ten
a
n
c
e
train
in
g
.
RT
O
HFM
S
y
mp
o
siu
m
o
n
Ad
v
a
n
c
e
d
T
e
c
h
n
o
lo
g
ies
fo
r
M
il
it
a
ry
T
ra
in
i
n
g
,
RT
O
-
M
PHFM
-
1
0
1
,
G
e
n
o
a
,
Ital
y
,
1
3
-
1
5
Oc
to
b
e
r
2
0
0
3
.
[3
]
A
RM
Y.M
IL
,
T
h
e
Offi
c
ia
l
Ho
me
p
a
g
e
o
f
th
e
U
n
it
e
d
S
t
a
tes
Army
.
(2
0
1
2
,
A
u
g
u
st
1
).
Re
tri
e
v
e
d
A
p
ril
3
,
2
0
1
5
,
f
ro
m
h
tt
p
:
//
ww
w
.
a
r
m
y
.
m
il
/articl
e
/8
4
4
5
3
/.
[4
]
Ba
d
ler,
N.
I.
,
Eri
g
n
a
c
,
C.
A
.
,
&
L
iu
,
Y.
(2
0
0
2
).
V
ir
tu
a
l
h
u
m
a
n
s
f
o
r
v
a
li
d
a
ti
n
g
m
a
in
ten
a
n
c
e
p
ro
c
e
d
u
re
.
Co
mm
u
n
ica
ti
o
n
s o
f
th
e
ACM
,
4
5
(
7
),
5
6
-
6
3
.
[5
]
Ba
k
e
r,
M
.
P
a
u
li
n
e
.
(2
0
1
4
).
V
ir
tu
a
l
re
a
li
ty
.
In
Acc
e
ss
S
c
ien
c
e
.
M
c
G
ra
w
-
Hill
Ed
u
c
a
ti
o
n
.
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:/
/
0
-
ww
w
.
a
c
c
e
ss
sc
ien
c
e
.
c
o
m
.
a
th
e
n
s.ii
i.
c
o
m
/co
n
ten
t/
v
ir
tu
a
l
-
re
a
li
ty
/7
5
7
4
6
1
.
[6
]
Ba
ro
t,
C.
L
o
u
r
d
e
a
u
x
,
D.,
B
u
rk
h
a
rd
t,
J.
A
m
o
k
ra
n
e
,
K.
Len
n
e
,
D.
(
2
0
1
3
).
V3
S
:
A
V
ir
tu
a
l
E
n
v
iro
n
m
e
n
t
f
o
r
Risk
-
M
a
n
a
g
e
m
e
n
t
T
ra
in
in
g
b
a
se
d
o
n
Hu
m
a
n
-
A
c
ti
v
it
ies
M
o
d
e
l.
Pre
se
n
c
e
-
T
e
leo
p
e
ra
to
rs
a
n
d
Vi
rt
u
a
l
E
n
v
iro
n
me
n
ts
.
2
2
(
1
)
:
1
-
1
9
.
[7
]
Ba
u
m
a
n
n
,
J
(1
9
9
3
).
M
il
it
a
ry
a
p
p
li
c
a
ti
o
n
s
o
f
Vi
rt
u
a
l
Rea
li
ty
.
Re
t
riev
e
d
f
ro
m
Hiti
.
Was
h
in
g
to
n
.
e
d
u
o
n
A
p
ril
2
0
,
2
0
1
6
.
[8
]
Be
a
t
y
,
J.
(2
0
0
6
).
Ha
n
d
b
o
o
k
o
f
v
irt
u
a
l
e
n
v
iro
n
m
e
n
ts.
Or
g
a
n
iz
a
ti
o
n
a
l
Res
e
a
rc
h
M
e
th
o
d
s
, 9
(
1
),
1
1
3
-
1
1
8
.
[9
]
Be
ll
,
H.H.,
T
h
e
Ef
f
e
c
ti
v
e
n
e
ss
o
f
Distrib
u
te
d
M
issi
o
n
T
ra
in
in
g
.
C
o
mm
u
n
ica
ti
o
n
s
o
f
t
h
e
ACM
,
4
2
(
9
),
7
2
-
78.
[1
0
]
Brig
g
s,
J.C.
(1
9
9
6
).
T
h
e
p
ro
m
ise
o
f
v
irt
u
a
l
re
a
li
ty
.
T
h
e
Fu
t
u
rist
,
3
0
(
5
),
1
3
.
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:
//
se
a
rc
h
.
p
r
o
q
u
e
st.co
m
.
a
th
e
n
s.ii
i.
c
o
m
/d
o
c
v
iew
/2
1
8
5
9
1
5
8
3
?
a
c
c
o
u
n
ti
d
=
8
4
1
1
[1
1
]
Brig
g
s,
J.
C.
(2
0
0
2
)
.
V
irt
u
a
l
re
a
li
ty
is
g
e
tt
in
g
re
a
l:
P
re
p
a
re
t
o
m
e
e
t
y
o
u
r
c
lo
n
e
.
T
h
e
Fu
t
u
rist
,
3
6
(
3
),
3
4
-
4
6
.
[1
2
]
Bo
e
in
g
'
s I/
IT
S
EC
2
0
0
9
T
e
c
h
n
o
l
o
g
y
De
m
o
n
stra
ti
o
n
s.
(2
0
0
9
).
M
il
it
a
ry
T
e
c
h
n
o
lo
g
y
,
3
3
(1
2
),
7
6
.
[1
3
]
Bo
u
c
h
a
rd
,
S
.
,
Ba
u
s
,
O.,
Be
rn
ier,
F
.
,
&
M
c
Cre
a
r
y
,
D.R.
(2
0
1
0
).
S
e
lec
ti
o
n
o
f
Ke
y
S
tres
so
rs
to
De
v
e
lo
p
V
irt
u
a
l
En
v
iro
n
m
e
n
ts
f
o
r
P
ra
c
ti
c
in
g
S
tres
s
M
a
n
a
g
e
m
e
n
t
S
k
il
ls
w
it
h
M
il
it
a
ry
P
e
rso
n
n
e
l
P
r
io
r
to
De
p
lo
y
m
e
n
t.
Cy
b
e
rp
sy
c
h
o
lo
g
y
,
Beh
a
v
io
r &
S
o
c
ia
l
Ne
two
rk
in
g
,
1
3
(
1
),
8
3
-
9
4
.
[1
4
]
Bo
u
g
h
o
u
a
s,
H.
,
B
o
u
k
e
b
b
a
b
,
S
.
,
Bo
u
c
h
e
n
it
f
a
,
H.,
&
A
m
a
ra
,
I.
(2
0
0
8
).
Co
n
tro
l
b
y
v
irt
u
a
l
g
a
u
g
e
o
f
sk
e
w
su
rfa
c
e
s
f
o
r
c
o
rre
c
ti
o
n
p
ro
c
e
ss
.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
A
d
v
a
n
c
e
d
M
a
n
u
fa
c
tu
rin
g
T
e
c
h
n
o
lo
g
y
,
3
6
(
9
/1
0
),
9
3
6
-
9
41.
[1
5
]
Bo
w
li
n
g
,
S
.
R.
,
Kh
a
sa
w
n
e
h
,
M
.
T
.
,
Ka
e
w
k
u
e
k
o
o
l,
S
.
,
X
iao
c
h
u
n
,
J.,
&
G
ra
m
o
p
a
d
h
y
e
,
A
.
K.
(2
0
0
8
).
E
v
a
lu
a
ti
n
g
th
e
Eff
e
c
ts
o
f
V
irt
u
a
l
T
ra
in
in
g
i
n
a
n
A
ircr
a
f
t
M
a
in
ten
a
n
c
e
T
a
sk
.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
Avia
ti
o
n
Psy
c
h
o
l
o
g
y
,
1
8
(1
),
104
-
1
1
6
.
[1
6
]
Bu
tav
iciu
s,
M
.
A
.
,
V
o
z
z
o
,
A
.
,
Br
a
it
h
w
a
it
e
,
H.,
&
G
a
lan
is,
G
.
(2
0
1
2
).
Ev
a
lu
a
ti
o
n
o
f
a
V
irt
u
a
l
Re
a
l
it
y
P
a
ra
c
h
u
te
T
ra
in
in
g
S
i
m
u
lato
r:
A
ss
e
ss
in
g
L
e
a
rn
in
g
in
a
n
Off
-
Co
u
rse
A
u
g
m
e
n
ted
F
e
e
d
b
a
c
k
T
ra
in
in
g
S
c
h
e
d
u
le.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
Avia
ti
o
n
Psy
c
h
o
lo
g
y
,
2
2
(3
),
2
8
2
-
2
9
8
.
[1
7
]
B
y
m
e
r,
L
.
(2
0
1
2
).
V
irt
u
a
l
Re
a
li
ty
u
se
d
to
train
so
ld
iers
i
n
n
e
w
train
in
g
sim
u
lato
r.
Re
t
riev
e
d
f
ro
m
ww
w
.
a
r
m
y
.
m
il
.
2
0
1
2
o
n
A
p
ril
2
8
,
2
0
1
6
.
[1
8
]
CA
E
E
-
L
e
a
rn
in
g
.
(n
.
d
.
).
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:/
/w
ww
.
c
a
e
.
c
o
m
/ci
v
il
-
a
v
iatio
n
/b
u
sin
e
ss
-
a
v
iatio
n
/ca
e
-
e
-
lea
rn
in
g
/
on
A
p
ril
2
8
,
2
0
1
6
.
[1
9
]
CA
E
V
irt
u
a
l
G
ro
u
n
d
S
c
h
o
o
l.
(
n
.
d
.
).
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:/
/www
.
c
a
e
.
c
o
m
/civ
il
-
a
v
iatio
n
/b
u
sin
e
ss
-
a
v
iatio
n
/t
ra
i
n
i
n
g
-
c
o
u
rse
s/c
a
e
-
v
irt
u
a
l
-
g
ro
u
n
d
-
sc
h
o
o
l/
o
n
A
p
ril
2
8
,
2
0
1
6
.
[2
0
]
Cra
n
e
,
P
.
(
1
9
9
9
).
Im
p
le
m
e
n
ti
n
g
d
istri
b
u
te
d
m
issio
n
train
i
n
g
.
Co
mm
u
n
ica
ti
o
n
s o
f
th
e
ACM
,
4
2
(
9
),
9
0
-
9
4
.
[2
1
]
Cre
ss
e
y
,
D.
(2
0
1
1
)
.
Q&
A
:
T
h
e
v
i
rtu
a
l
train
e
r
.
Na
t
u
re
,
4
7
7
(
7
3
6
5
),
4
0
6
=
4
0
8
.
[2
2
]
Da
n
ig
e
li
s,
A
.
(n
.
d
.
).
Ro
b
o
ti
c
Ha
n
d
S
h
a
k
e
s
Y
o
u
rs
fo
r
L
o
n
g
Dista
n
c
e
Gr
e
e
ti
n
g
:
DNe
ws
.
Re
tri
e
v
e
d
,
f
ro
m
h
tt
p
:
//
n
e
w
s.d
isc
o
v
e
r
y
.
c
o
m
/t
e
c
h
/ro
b
o
ti
c
s/r
o
b
o
ti
c
-
h
a
n
d
-
sh
a
k
e
s
-
y
o
u
rs
-
f
o
r
-
lo
n
g
-
d
istan
c
e
-
g
re
e
ti
n
g
-
1
4
0
4
2
8
.
h
tm
o
n
A
p
ril
5
,
2
0
1
5
[2
3
]
De
it
z
,
D.
(1
9
9
5
)
.
Re
a
l
e
n
g
in
e
e
rin
g
in
a
v
irt
u
a
l
w
o
rld
.
M
e
c
h
a
n
i
c
a
l
En
g
in
e
e
rin
g
,
1
1
7
(7
)
,
7
8
.
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:
//
se
a
rc
h
.
p
r
o
q
u
e
st.co
m
.
a
th
e
n
s.ii
i.
c
o
m
/d
o
c
v
iew
/2
3
0
1
5
9
9
0
6
?
a
c
c
o
u
n
ti
d
=
8
4
1
1
o
n
A
p
ril
2
8
,
2
0
1
6
.
[2
4
]
Em
il
y
,
A
.
T
.
,
&
Bo
d
a
ry
,
M
.
(2
0
0
0
).
V
irt
u
a
l
re
a
li
ty
,
c
o
m
b
a
t,
a
n
d
c
o
m
m
u
n
ica
ti
o
n
.
J
o
u
rn
a
l
o
f
Bu
sin
e
ss
a
n
d
T
e
c
h
n
ica
l
C
o
mm
u
n
ica
ti
o
n
,
1
4
(3
)
,
3
1
5
-
3
2
7
.
[2
5
]
F
AA
(2
0
1
4
).
FA
A
la
b
u
sin
g
v
irt
u
a
l
re
a
li
ty
to
im
p
ro
v
e
a
v
ia
t
io
n
sa
fety
.
Re
tr
iev
e
d
,
f
ro
m
h
tt
p
:
//
ww
w
.
p
re
ss
o
f
a
tl
a
n
ti
c
c
it
y
.
c
o
m
/co
m
m
u
n
it
ies
/eh
t/
f
a
a
-
lab
-
u
sin
g
-
v
irt
u
a
l
-
re
a
li
ty
-
to
-
i
m
p
ro
v
e
-
a
v
i
a
ti
o
n
-
sa
fe
t
y
/article
_
3
e
0
3
0
a
5
6
-
e
f
5
c
-
1
1
e
3
-
a
2
a
0
-
0
0
1
a
4
b
c
f
8
8
7
a
.
h
tm
l
o
n
A
p
ril
2
,
2
0
1
5
[2
6
]
F
e
ld
m
a
n
n
,
K.,
&
Ch
risto
p
h
,
F
.
(2
0
0
3
).
V
irt
u
a
l
p
ro
t
o
ty
p
in
g
o
f
p
lac
e
m
e
n
t
m
a
c
h
in
e
s
in
e
lec
tro
n
ics
p
ro
d
u
c
ti
o
n
.
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
C
o
mp
u
ter
In
teg
ra
te
d
M
a
n
u
f
a
c
tu
rin
g
,
1
6
(
7
/8
),
4
7
9
-
4
8
5
.
[2
7
]
G
a
o
li
a
n
g
,
P
.
,
Yu
,
H.,
L
iu
,
X
.
,
Jia
n
g
,
Y.,
&
X
u
,
H.
(2
0
1
0
).
A
d
e
s
k
to
p
v
irt
u
a
l
re
a
li
ty
-
b
a
se
d
in
teg
r
a
te
d
s
y
ste
m
f
o
r
c
o
m
p
lex
p
ro
d
u
c
t
m
a
in
tain
a
b
il
i
ty
d
e
sig
n
a
n
d
v
e
rif
ica
ti
o
n
.
Asse
mb
ly
Au
t
o
ma
ti
o
n
,
30
(4
)
,
3
3
3
-
3
4
4
.
[2
8
]
G
a
r
f
in
k
le,
T
.
,
Ro
se
n
b
lu
m
,
M
.
(2
0
0
5
).
W
h
ich
V
irt
u
a
l
is
h
a
rd
e
r
t
h
a
n
Re
a
l;
S
e
c
u
rit
y
c
h
a
ll
e
n
g
e
s
in
V
irt
u
a
l
M
a
c
h
in
e
b
a
se
d
c
o
m
p
u
ti
n
g
e
n
v
iro
n
m
e
n
ts.
Pro
c
e
e
d
i
n
g
s
o
f
th
e
1
0
t
h
W
o
rk
sh
o
p
.
2
0
0
5
.
Re
t
riev
e
d
f
ro
m
h
tt
p
s:/
/www
.
u
se
n
ix
.
o
rg
/l
e
g
a
c
y
/ev
e
n
t/
h
o
to
s0
5
/f
in
a
l_
p
a
p
e
rs/f
u
ll
_
p
a
p
e
rs/g
a
r
f
in
k
e
l/
g
a
r
f
in
k
e
l.
p
d
f
o
n
A
p
ril
2
8
,
2
0
1
6.
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
,
Decem
b
er
201
6
:
2
6
9
8
–
2
7
0
7
2704
[2
9
]
G
o
p
h
e
r,
D.
(
2
0
1
2
)
.
S
k
il
l
tr
a
in
i
n
g
i
n
M
u
lt
imo
d
a
l
v
irtu
a
l
e
n
v
iro
n
me
n
ts
.
W
o
rk
,
4
1
2
2
8
4
-
2
2
8
7
.
Re
t
riev
e
d
f
ro
m
h
tt
p
:
//
0
-
w
e
b
.
b
.
e
b
sc
o
h
o
st.co
m
.
a
th
e
n
s.ii
i.
c
o
m
/eh
o
st/d
e
tail/
d
e
tail?v
id
=
2
2
&
sid
=
f
7
b
9
9
0
f
a
-
e
e
f
3
-
46be
-
8
e
d
c
-
8
a
5
9
3
d
b
0
b
f
1
6
%
4
0
se
ss
io
n
m
g
r1
1
4
&
h
id
=
1
0
9
&
b
d
a
ta=
Jn
Np
d
G
U9
ZW
h
v
c
3
Qtb
G
l2
ZQ%
3
d
%
3
d
#
d
b
=
b
u
h
&
A
N=
7
1
9
2
8
6
0
7
A
p
ril
2
8
,
2
0
1
6
.
[3
0
]
G
o
r
m
a
n
P
J,
M
e
ier
A
H,
&
Kru
m
m
e
l
T
M
.
S
i
m
u
latio
n
a
n
d
V
irt
u
a
l
Re
a
li
t
y
in
S
u
rg
ica
l
Ed
u
c
a
ti
o
n
:
R
e
a
l
or
Un
re
a
l?
Arc
h
S
u
r
g
.
1
9
9
9
;
1
3
4
(
1
1
):
1
2
0
3
-
1
2
0
8
.
[3
1
]
G
o
o
lsb
y
,
C.
,
V
e
st,
R.
,
&
G
o
o
d
w
in
,
T.
(2
0
1
4
)
.
Ne
w
W
id
e
A
re
a
V
irt
u
a
l
En
v
iro
n
m
e
n
t
(W
A
V
E)
M
e
d
i
c
a
l
Ed
u
c
a
ti
o
n
.
M
il
it
a
ry
M
e
d
icin
e
,
1
7
9
(
1
),
38
-
4
1.
[3
2
]
Gw
e
b
u
,
K.L
.
,
W
a
n
g
,
J.,
&
T
ro
u
t
t,
M
.
D.
(2
0
0
7
).
A
c
o
n
c
e
p
t
u
a
l
f
ra
m
e
w
o
rk
f
o
r
u
n
d
e
rsta
n
d
i
n
g
tru
st
b
u
il
d
in
g
a
n
d
m
a
in
ten
a
n
c
e
in
v
irt
u
a
l
o
rg
a
n
iza
ti
o
n
.
J
IT
T
A:
J
o
u
rn
a
l
o
f
In
f
o
rm
a
ti
o
n
T
e
c
h
n
o
lo
g
y
T
h
e
o
ry
a
n
d
A
p
p
li
c
a
ti
o
n
, 9
(1
)
,
4
3
-
63.
[3
3
]
Ha
ss
o
u
n
e
h
,
D.,
&
Bre
n
g
m
a
n
,
M
.
(2
0
1
1
)
.
Virtu
a
l
w
o
rld
s:
A
g
a
te
w
a
y
f
o
r
S
M
Es
to
w
a
rd
in
tern
a
ti
o
n
a
li
z
a
ti
o
n
.
J
o
u
rn
a
l
o
f
Bra
n
d
M
a
n
a
g
e
me
n
t,
19
(1
),
7
2
-
9
0
.
[3
4
]
Ha
y
s,
R.
T
.
,
V
in
c
e
n
z
i,
D.A
.
(2
0
0
2
).
F
lee
t
A
ss
e
ss
m
e
n
ts
o
f
a
V
irt
u
a
l
Re
a
li
t
y
T
r
a
in
in
g
S
y
st
e
m
.
M
il
it
a
ry
P
sy
c
h
o
lo
g
y
(T
a
y
lo
r
a
n
d
F
ra
n
c
is
L
td
),
1
2
(
3
),
1
6
1
-
1
8
6
.
[3
5
]
He
n
d
e
rso
n
,
L
.
(2
0
1
3
)
.
Cli
n
ica
l
T
e
c
h
n
o
l
o
g
ies
.
A
p
p
li
e
d
Cli
n
ica
l
T
rials,
2
2
(
1
2
),
1
8
-
22.
[3
6
]
Histo
ry
o
f
Vi
rt
u
a
l
Rea
l
it
y
.
(n
.
d
.
)
.
Re
tri
e
v
e
d
A
p
ril
5
,
2
0
1
5
,
f
ro
m
h
tt
p
:/
/w
ww
.
v
rs.o
rg
.
u
k
/v
irt
u
a
l
-
re
a
li
t
y
/h
isto
ry
.
h
tm
l
[3
7
]
Ho
w
a
rd
,
C.
E.
(2
0
1
2
)
.
Im
m
e
rsi
v
e
train
in
g
f
o
r
a
n
a
g
il
e
,
a
d
a
p
tab
l
e
f
o
rc
e
.
M
il
it
a
ry
a
n
d
Aer
o
sp
a
c
e
El
e
c
tro
n
ics
,
2
3
(
1
1
),
1
0
-
1
7
.
[3
8
]
Hu
b
a
l,
R.
(
2
0
0
5
).
De
sig
n
a
n
d
u
sa
b
il
it
y
o
f
m
il
it
a
r
y
m
a
in
ten
a
n
c
e
sk
i
ll
s
sim
u
latio
n
train
i
n
g
s
y
ste
m
s.
P
ro
c
e
e
d
in
g
s
o
f
th
e
Hu
ma
n
F
a
c
to
rs
a
n
d
Erg
o
n
o
mic
s
S
o
c
iety
A
n
n
u
a
l
M
e
e
ti
n
g
(p
p
.
2
1
1
0
-
2
1
1
4
).
S
a
n
ta
M
o
n
ica
,
CA
:
Hu
m
a
n
F
a
c
to
rs an
d
Erg
o
n
o
m
ics
S
o
c
iet
y
.
[3
9
]
Hu
e
g
a
l,
J.
C
e
li
k
,
O.,
Isr
a
r,
A
.
,
O’Malle
y
,
M
.
,
Ex
p
e
rti
se
-
Ba
s
e
d
P
e
rf
o
rm
a
n
c
e
M
e
a
su
re
s
in
a
V
irt
u
a
l
T
ra
in
in
g
En
v
iro
n
m
e
n
t.
Pre
se
n
c
e
:
T
e
leo
p
e
r
a
to
rs
a
n
d
Vi
rt
u
a
l
En
v
iro
n
me
n
ts
,
1
8
(
6
),
4
4
9
-
4
6
7
.
[4
0
]
Ja
m
e
sto
n
,
H.,
In
tera
c
ti
v
e
a
n
d
Im
m
e
rsiv
e
T
ra
in
in
g
.
M
il
it
a
ry
T
e
c
h
n
o
lo
g
y
.
2
0
1
1
.
3
5
(
5
).
5
6
-
6
3
.
[4
1
]
Je
a
n
,
G
.
B.
(2
0
0
9
).
U
n
m
a
n
n
e
d
A
e
rial
V
e
h
icle
s Jo
in
th
e
V
irt
u
a
l
F
ig
h
t.
Na
ti
o
n
a
l
De
fen
se
,
9
3
(
6
6
8
),
3
2
-
33.
[4
2
]
Je
n
a
b
,
K.,
&
Zo
lf
a
g
h
a
ri,
S
.
(
2
0
0
8
).
A
v
irt
u
a
l
c
o
ll
a
b
o
ra
ti
v
e
m
a
in
t
e
n
a
n
c
e
a
rc
h
it
e
c
tu
re
f
o
r
m
a
n
u
f
a
c
tu
rin
g
e
n
terp
rise
s.
J
o
u
r
n
a
l
o
f
I
n
telli
g
e
n
t
M
a
n
u
f
a
c
tu
ri
n
g
,
19
(6
),
7
6
3
-
7
7
1
.
[4
3
]
Ji,
P
.
,
Ch
o
i
,
A
.
C.
K.,
&
T
u
,
L
.
(2
0
0
2
).
V
DA
S
:
A
v
irt
u
a
l
d
e
sig
n
a
n
d
a
ss
e
m
b
l
y
s
y
st
e
m
in
a
v
irt
u
a
l
re
a
li
t
y
e
n
v
iro
n
m
e
n
t.
Asse
mb
ly A
u
t
o
ma
ti
o
n
,
2
2
(4
),
3
3
7
-
3
4
2
.
[4
4
]
Jia
n
,
C.
,
&
X
i
u
m
in
,
F
.
(
2
0
1
0
).
Dy
n
a
m
i
c
M
o
d
e
l
o
f
a
n
A
stro
n
a
u
t
E
q
u
i
p
p
e
d
w
it
h
a
M
a
n
n
e
d
M
a
n
e
u
v
e
rin
g
Un
it
i
n
V
irt
u
a
l
Re
a
li
ty
.
J
o
u
rn
a
l
o
f
Aer
o
sp
a
c
e
En
g
in
e
e
rin
g
,
2
3
(
2
),
1
3
9
-
1
4
5
.
[4
5
]
Ka
b
e
r,
D.
1
3
,
Ri
ley
,
J.M
.
,
En
d
sle
y
,
M
.
B.
,
S
h
e
ik
-
Na
in
a
r,
Z
h
a
n
g
,
T
.
,
L
a
m
p
to
n
.
D.R
.
,
(
2
0
1
3
).
M
e
a
su
r
in
g
S
it
u
a
ti
o
n
Aw
a
re
n
e
ss
in
V
irt
u
a
l
b
a
se
d
T
ra
in
in
g
.
M
il
it
a
ry
Psy
c
h
o
lo
g
y
(
Ame
ric
a
n
Psy
c
h
o
lo
g
y
Asso
c
ia
ti
o
n
)
,
2
5
(
4
),
3
3
0
-
3
4
4
.
[4
6
]
Ka
o
,
Y.,
T
sa
i,
J.,
Ch
e
n
g
,
H.,
&
Ch
a
o
,
C.
(2
0
1
1
).
De
v
e
lo
p
m
e
n
t
o
f
a
v
irt
u
a
l
re
a
li
t
y
w
ire
e
lec
tri
c
a
l
d
isc
h
a
rg
e
mach
in
in
g
sy
st
e
m
f
o
r
o
p
e
ra
ti
o
n
t
ra
in
in
g
.
In
tern
a
ti
o
n
a
l
Jo
u
rn
a
l
o
f
A
d
v
a
n
c
e
d
M
a
n
u
f
a
c
tu
rin
g
T
e
c
h
n
o
lo
g
y
,
5
4
(5
-
8
),
605
-
6
1
8
.
[4
7
]
L
a
m
,
C.
K.,
S
u
n
d
a
ra
j,
K.,
&
S
u
laim
a
n
,
M
.
N.
(2
0
1
3
).
A
Re
v
ie
w
o
f
Co
m
p
u
ter
-
Ge
n
e
ra
ted
S
i
m
u
latio
n
i
n
th
e
P
e
d
a
g
o
g
y
o
f
Ca
tara
c
t
S
u
rg
e
r
y
T
r
a
in
in
g
a
n
d
A
ss
e
ss
m
e
n
t.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
Hu
ma
n
-
Co
mp
u
te
r
In
ter
a
c
ti
o
n
,
2
9
(
1
0
),
6
6
1
-
6
6
9
.
[4
8
]
L
a
n
d
e
rs.
R.
N.,
Ca
ll
a
n
.
R.
C.
(
2
0
1
2
).
T
ra
in
in
g
Ev
a
lu
a
ti
o
n
in
V
ir
tu
a
l
W
o
rld
s:
De
v
e
lo
p
m
e
n
t
o
f
a
m
o
d
e
l.
J
o
u
rn
a
l
o
f
Vi
rtu
a
l
W
o
rld
s R
e
se
a
rc
h
.
5
(
3
).
1
-
22.
[4
9
]
L
a
rs
e
n
,
C.
R.
Oe
ste
rg
a
a
rd
,
J
.
,
Ot
t
e
se
n
,
B.
S
.
&
S
o
e
re
n
se
n
,
J.L
.
(2
0
1
2
).
T
h
e
e
ff
ica
c
y
o
f
v
irt
u
a
l
re
a
li
ty
si
m
u
latio
n
train
in
g
in
lap
a
ro
sc
o
p
y
:
a
s
y
s
tem
a
ti
c
re
v
ie
w
o
f
ra
n
d
o
m
ize
d
tri
a
ls.
Acta
Ob
ste
tricia
Et
Gy
n
e
c
o
lo
g
ic
a
S
c
a
n
d
in
a
v
ica
,
9
1
(
9
),
1
0
1
5
-
1
0
2
8
.
d
o
i:
1
0
.
1
1
1
1
/j
.
1
6
0
0
-
0
4
1
2
.
2
0
1
2
.
0
1
4
8
2
.
x
[5
0
]
L
a
te
e
f
,
F
(n
.
d
.
)
.
S
im
u
latio
n
-
b
a
se
d
lea
rn
i
n
g
:
ju
st
li
k
e
th
e
re
a
l
th
i
n
g
.
J
o
u
r
n
a
l
o
f
Eme
rg
e
n
c
ies
,
T
r
a
u
m
a
,
a
n
d
S
h
o
c
k
,
3
(4
),
3
4
8
-
3
5
2
.
[5
1
]
L
i,
D.,
Hu
a
n
g
,
W
.
,
Ch
e
n
,
C.
,
&
Ch
a
n
g
,
C.
(2
0
1
3
).
Em
p
lo
y
in
g
v
irt
u
a
l
sa
m
p
les
to
b
u
il
d
e
a
rly
h
ig
h
-
d
im
e
n
sio
n
a
l
m
a
n
u
f
a
c
tu
rin
g
m
o
d
e
ls
.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
Pro
d
u
c
ti
o
n
Res
e
a
rc
h
,
5
1
(
1
1
)
,
3
2
0
6
-
3
2
2
4
.
d
o
i:
1
0
.
1
0
8
0
/
0
0
2
0
7
5
4
3
.
2
0
1
2
.
7
4
6
7
9
5
[5
2
]
L
i,
X
.
,
G
a
o
,
Q.,
Zh
a
n
g
,
Z.
,
&
H
u
a
n
g
,
X
.
(2
0
1
2
).
Co
l
lab
o
ra
ti
v
e
v
irt
u
a
l
m
a
in
ten
a
n
c
e
train
in
g
s
y
st
e
m
o
f
c
o
m
p
lex
e
q
u
ip
m
e
n
t
b
a
se
d
o
n
imm
e
rsi
v
e
v
irt
u
a
l
re
a
li
t
y
e
n
v
iro
n
m
e
n
t.
Asse
mb
ly
Au
to
m
a
ti
o
n
,
32
(1
)
,
7
2
-
8
5
.
d
o
i:
h
tt
p
:
//
0
-
d
x
.
d
o
i
.
o
rg
.
a
th
e
n
s
.
ii
i.
c
o
m
/1
0
.
1
1
0
8
/0
1
4
4
5
1
5
1
2
1
1
1
9
8
7
3
7
[5
3
]
L
iu
,
X
.
,
Cu
i,
X
.
,
S
o
n
g
,
G
.
,
&
X
u
,
B.
(2
0
1
4
).
De
v
e
lo
p
m
e
n
t
o
f
a
v
irt
u
a
l
m
a
in
ten
a
n
c
e
s
y
ste
m
w
it
h
v
irt
u
a
l
h
a
n
d
.
In
ter
n
a
t
io
n
a
l
J
o
u
r
n
a
l
Of
A
d
v
a
n
c
e
d
M
a
n
u
fa
c
t
u
rin
g
T
e
c
h
n
o
l
o
g
y
,
70
(9
-
1
2
),
2
2
4
1
-
2
2
4
7
.
d
o
i
:
1
0
.
1
0
0
7
/s0
0
1
7
0
-
0
1
3
-
5
4
7
3
-
0
[5
4
]
L
iu
,
X
.
,
P
e
n
g
,
G
.
,
L
iu
,
X
.
,
&
Ho
u
,
Y.
(2
0
1
2
).
Disa
ss
e
m
b
l
y
se
q
u
e
n
c
e
p
lan
n
in
g
a
p
p
ro
a
c
h
f
o
r
p
ro
d
u
c
t
v
irt
u
a
l
m
a
in
ten
a
n
c
e
b
a
se
d
o
n
im
p
ro
v
e
d
m
a
x
-
m
in
a
n
t
sy
ste
m
.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
A
d
v
a
n
c
e
d
M
a
n
u
f
a
c
tu
ri
n
g
T
e
c
h
n
o
l
o
g
y
,
5
9
(5
-
8
),
8
2
9
-
8
3
9
.
d
o
i:
1
0
.
1
0
0
7
/s0
0
1
7
0
-
0
1
1
-
3
5
3
1
-
z
[5
5
]
L
ö
v
q
u
ist,
E.
,
S
h
o
rten
,
G
.
,
&
A
b
o
u
laf
ia,
A
.
(2
0
1
2
).
V
irt
u
a
l
re
a
li
t
y
-
b
a
s
e
d
m
e
d
ica
l
train
in
g
a
n
d
a
ss
e
ss
m
e
n
t:
T
h
e
m
u
lt
id
isc
ip
li
n
a
ry
re
latio
n
sh
i
p
b
e
t
w
e
e
n
c
li
n
icia
n
s,
e
d
u
c
a
to
rs
a
n
d
d
e
v
e
lo
p
e
rs.
M
e
d
ica
l
T
e
a
c
h
e
r
,
3
4
(
1
),
5
9
-
6
4
.
d
o
i:
1
0
.
3
1
0
9
/
0
1
4
2
1
5
9
X
.
2
0
1
1
.
6
0
0
3
5
9
.
[5
6
]
L
u
e
c
k
e
,
G
.
R.
(2
0
1
2
)
.
G
REE
NSP
A
CE:
V
irt
u
a
l
Re
a
li
ty
In
ter
f
a
c
e
f
o
r
Co
m
b
in
e
Op
e
ra
to
r
T
ra
in
in
g
.
Pre
se
n
c
e
:
T
e
leo
p
e
ra
t
o
rs
&
Vi
rtu
a
l
E
n
v
iro
n
me
n
ts
,
2
1
(3
),
2
4
5
-
2
5
3
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2088
-
8708
V
ir
tu
a
l Ma
in
ten
a
n
ce
,
R
e
a
lity,
a
n
d
S
ystems
:
A
R
ev
iew
(
K
o
u
r
o
u
s
h
Je
n
a
b
)
2705
[5
7
]
M
e
y
e
r,
G
.
F
.
,
L
i
T
in
g
,
W
.
,
T
i
m
so
n
,
E.
,
P
e
rf
e
c
t,
P
.
,
W
h
it
e
,
M
.
D.,
&
Ern
st,
M
.
O.
(2
0
1
2
).
Ob
j
e
c
ti
v
e
F
id
e
li
t
y
Ev
a
lu
a
ti
o
n
in
M
u
lt
ise
n
so
ry
V
irt
u
a
l
En
v
iro
n
m
e
n
ts:
A
u
d
it
o
ry
Cu
e
F
id
e
li
ty
in
F
l
ig
h
t
S
im
u
latio
n
.
Pl
o
s
ONE
,
7
(
9
),
1
-
1
4
.
d
o
i:
1
0
.
1
3
7
1
/
jo
u
rn
a
l.
p
o
n
e
.
0
0
4
4
3
8
1
.
[5
8
]
M
il
it
a
ry
a
p
p
l
ica
ti
o
n
s
o
f
v
irtu
a
l
re
a
li
ty
.
(n
.
d
.
).
Re
tri
e
v
e
d
A
p
ril
2
,
2
0
1
5
,
f
ro
m
h
tt
p
:
//
ww
w
.
h
it
l.
w
a
sh
in
g
to
n
.
e
d
u
/
p
ro
jec
ts/k
n
o
w
led
g
e
_
b
a
se
/v
irt
u
a
l
-
wo
rld
s/E
V
E
/II.
G
.
M
il
it
a
ry
.
h
tm
l
[5
9
]
M
o
o
re
,
P.
R.
,
Ng
,
A
.
C.
,
Ye
o
,
S
.
H.,
S
u
n
d
b
e
rg
,
M
.
,
W
o
n
g
,
C.
B.
,
&
De
V
in
,
L
.
J.
(2
0
0
8
).
A
d
v
a
n
c
e
d
m
a
c
h
in
e
se
rv
ice
su
p
p
o
rt
u
si
n
g
In
tern
e
t
-
e
n
a
b
led
t
h
re
e
-
d
ime
n
sio
n
a
l
-
b
a
se
d
v
irt
u
a
l
e
n
g
in
e
e
rin
g
.
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
Pro
d
u
c
ti
o
n
Res
e
a
rc
h
,
4
6
(
1
5
)
,
4
2
1
5
-
4
2
3
5
.
d
o
i
:
1
0
.
1
0
8
0
/0
0
2
0
7
5
4
0
6
0
0
9
6
9
7
9
0
.
[6
0
]
M
o
sk
a
li
v
k
,
J.
Be
tra
m
,
J.,
Cre
ss
,
V
.
,
Im
p
a
c
t
o
f
V
irt
u
a
l
T
ra
in
in
g
En
v
iro
n
m
e
n
ts
o
n
th
e
A
c
q
u
isit
io
n
s
a
n
d
T
ra
sn
f
e
r
o
f
Kn
o
w
led
g
e
.
Cy
b
e
rPsy
c
h
o
lo
g
y
,
B
e
h
a
v
io
r
a
n
d
S
o
c
ia
l
Ne
two
rk
in
g
.
1
6
(3
).
2
1
0
-
2
1
4
.
2
0
1
3
.
[6
1
]
M
u
e
ll
e
r,
D.,
&
S
tr
o
h
m
e
ier,
S
.
(2
0
1
0
).
De
sig
n
c
h
a
ra
c
teristics
o
f
v
irt
u
a
l
lea
rn
i
n
g
e
n
v
iro
n
m
e
n
ts:
a
n
e
x
p
e
rt
stu
d
y
.
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
T
ra
in
in
g
&
De
v
e
lo
p
me
n
t
,
1
4
(3
),
2
0
9
-
2
2
2
.
d
o
i:
1
0
.
1
1
1
1
/j
.
1
4
6
8
-
2
4
1
9
.
2
0
1
0
.
0
0
3
5
3
.
x
.
[6
2
]
Na
m
b
isa
n
,
S
.
,
&
Ba
ro
n
,
R.
A
.
(2
0
0
9
).
V
ir
tu
a
l
Cu
st
o
m
e
r
En
v
iro
n
m
e
n
ts:
T
e
stin
g
a
M
o
d
e
l
o
f
V
o
l
u
n
tary
P
a
rti
c
i
p
a
ti
o
n
in
V
a
l
u
e
Co
-
c
re
a
ti
o
n
A
c
ti
v
it
ies
.
J
o
u
rn
a
l
o
f
Pro
d
u
c
t
In
n
o
v
a
ti
o
n
M
a
n
a
g
e
me
n
t
,
2
6
(4
)
,
3
8
8
-
4
0
6
.
d
o
i:
1
0
.
1
1
1
1
/
j.
1
5
4
0
-
5
8
8
5
.
2
0
0
9
.
0
0
6
6
7
.
x
.
[6
3
]
Na
k
a
y
a
m
a
,
S
.
,
&
Jin
,
G
.
(2
0
1
5
)
.
S
a
f
e
t
y
train
in
g
:
En
h
a
n
c
i
n
g
o
u
tc
o
m
e
s
th
ro
u
g
h
v
irt
u
a
l
e
n
v
iro
n
m
e
n
ts
.
P
ro
fes
sio
n
a
l
S
a
fety
,
60
(
2
),
3
4
-
3
8
.
[6
4
]
Niu
,
L
.
,
&
Yu
a
n
,
Y.
(
2
0
1
1
)
.
A
p
a
ra
ll
e
l
d
e
c
o
m
p
o
siti
o
n
a
lg
o
ri
th
m
f
o
r
train
in
g
m
u
lt
icla
ss
k
e
rn
e
l
-
b
a
se
d
v
e
c
to
r
m
a
c
h
in
e
s.
Op
ti
m
iza
ti
o
n
M
e
th
o
d
s
&
S
o
f
twa
re
,
2
6
(3
),
4
3
1
-
4
5
4
.
d
o
i:
1
0
.
1
0
8
0
/
1
0
5
5
6
7
8
8
.
2
0
1
1
.
5
5
6
6
3
3
.
[6
5
]
No
o
r,
A
.
K.
(2
0
0
9
).
Disr
u
p
ti
o
n
f
ro
m
v
irt
u
a
l
w
o
rld
.
M
e
c
h
a
n
ic
a
l
E
n
g
i
n
e
e
rin
g
,
1
3
1
(1
1
),
2
2
-
2
8
.
[6
6
]
Nu
g
e
n
t,
W
.
R.
(
1
9
9
1
).
V
irt
u
a
l
re
a
li
ty
:
A
d
v
a
n
c
e
d
im
a
g
in
g
sp
e
c
ial
e
ff
e
c
ts
let
y
o
u
ro
a
m
in
c
y
b
e
rsp
a
c
e
.
J
o
u
rn
a
l
o
f
th
e
Ame
ric
a
n
S
o
c
iety
f
o
r In
f
o
rm
a
ti
o
n
S
c
ien
c
e
(
1
9
8
6
-
1
9
9
8
),
42
(
8
),
6
0
9
-
9
1
8
.
[6
7
]
O
n
g
,
S
.
K.,
Yu
a
n
,
M
.
L
.
,
&
Ne
e
,
A
.
C.
(2
0
0
8
)
.
A
u
g
m
e
n
ted
re
a
li
ty
a
p
p
li
c
a
ti
o
n
s
in
m
a
n
u
f
a
c
tu
rin
g
:
a
su
rv
e
y
.
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
Pr
o
d
u
c
ti
o
n
Res
e
a
rc
h
,
4
6
(1
0
),
2
7
0
7
-
2
7
4
2
.
d
o
i:
1
0
.
1
0
8
0
/0
0
2
0
7
5
4
0
6
0
1
0
6
4
7
7
3
.
[6
8
]
P
a
rso
n
s,
D.
(2
0
1
2
).
S
o
ld
iers
T
e
st
I
m
p
a
c
t
o
f
V
irt
u
a
l
T
ra
in
i
n
g
o
n
L
iv
e
-
f
ire
P
e
rf
o
r
m
a
n
c
e
.
Na
ti
o
n
a
l
De
fen
se
,
9
7
(
7
0
9
),
3
4
-
36.
[6
9
]
P
a
tel,
H.,
&
Ca
rd
i
n
a
li
,
R
.
(1
9
9
4
).
V
irt
u
a
l
re
a
li
ty
tec
h
n
o
lo
g
y
in
b
u
si
n
e
ss
.
M
a
n
a
g
e
me
n
t
De
c
isio
n
,
32
(7
),
5
-
18.
[7
0
]
P
icc
o
li
,
G
.
,
A
h
m
a
d
,
R.
,
&
Iv
e
s,
B.
(2
0
0
1
).
W
e
b
-
Ba
se
d
Virtu
a
l
L
e
a
rn
in
g
En
v
ir
o
n
m
e
n
ts:
A
Re
se
a
rc
h
F
ra
m
e
k
w
o
rk
a
n
d
a
P
re
li
m
in
a
ry
A
s
se
ss
m
e
n
t
o
f
Eff
e
c
ti
v
e
n
e
ss
in
Ba
sic
IT
S
k
il
ls
Train
in
g
.
M
IS
Q
u
a
rte
rly
,
2
5
(
4
),
4
0
1
-
4
2
6
[7
1
]
P
o
p
,
E.
,
L
e
b
a
,
M
.
,
&
Ne
g
h
in
a
,
F
.
(2
0
0
9
).
S
o
f
twa
re
Ori
e
n
ted
A
d
a
p
ti
v
e
Co
n
tro
ll
e
r
f
o
r
a
M
in
in
g
El
e
v
a
to
r.
Rev
ista
M
in
e
lo
r
/
M
in
i
n
g
Rev
u
e
,
1
5
(6
)
,
2
-
8
.
[7
2
]
P
RA
CT
ICED
H
A
ND
S
.
(2
0
0
6
).
P
C
M
a
g
a
zi
n
e
,
2
5
(1
7
),
2
0
.
[7
3
]
Oh
a
b
,
J.
(
2
0
1
0
)
.
T
h
re
e
wa
y
s
v
irtu
a
l
re
a
li
ty
c
a
n
imp
r
o
v
e
mili
ta
r
y
tra
in
i
n
g
.
Re
tri
e
v
e
d
o
n
M
a
y
1
5
,
2
0
1
6
,
f
ro
m
h
tt
p
:
//
sc
ien
c
e
.
d
o
d
li
v
e
.
m
il
/2
0
1
0
/0
7
/3
0
/t
h
re
e
-
w
a
y
s
-
v
irt
u
a
l
-
re
a
li
t
y
-
c
a
n
-
im
p
ro
v
e
-
m
il
it
a
r
y
-
train
in
g
/.
[7
4
]
Qiu
S
,
F
a
n
X
,
W
u
D,
He
Q,
&
Zh
o
u
D.
(
2
0
1
3
)
.
Virtu
a
l
h
u
m
a
n
m
o
d
e
li
n
g
f
o
r
in
tera
c
ti
v
e
a
ss
e
m
b
l
y
a
n
d
d
isa
ss
e
m
b
l
y
o
p
e
ra
ti
o
n
i
n
v
irt
u
a
l
re
a
li
ty
e
n
v
iro
n
m
e
n
t.
In
ter
n
a
ti
o
n
a
l
J
o
u
r
n
a
l
o
f
A
d
v
a
n
c
e
d
M
a
n
u
fa
c
t
u
rin
g
T
e
c
h
n
o
l
o
g
y
.
6
9
(9
-
1
2
)
,
2
3
5
5
-
2
3
7
2
.
[7
5
]
Rig
e
ls
f
o
rd
,
J.
(
2
0
0
4
).
V
irt
u
a
l
re
a
li
ty
te
c
h
n
o
l
o
g
y
.
Asse
mb
ly A
u
to
m
a
t
io
n
,
24
(1
),
1
2
7
-
1
2
9
.
[7
6
]
Ro
o
k
s,
B.
(
1
9
9
9
)
.
T
h
e
re
a
li
ty
o
f
v
irt
u
a
l
re
a
li
ty
.
Asse
mb
ly A
u
to
m
a
ti
o
n
,
19
(
3
),
2
0
3
-
2
1
2
[7
7
]
Ro
se
,
F
.
D,
A
lt
re
e
,
E.
A
.
,
Bro
o
k
s,
B.
M
.
,
P
a
rslo
w
,
D.M
.
,
P
e
n
n
,
P
.
R.
(2
0
0
0
).
T
ra
in
in
g
i
n
v
irt
u
a
l
e
n
v
iro
n
m
e
n
ts;
tran
sf
e
r
to
re
a
l
w
o
rld
tas
k
s an
d
e
q
u
iv
a
len
c
e
to
re
a
l
tas
k
train
in
g
.
Er
g
o
n
o
mic
s
.
4
3
(
4
),
4
9
4
-
5
1
1
.
[7
8
]
Ro
se
n
b
e
rg
,
B.
(2
0
0
2
).
L
o
c
k
h
e
e
d
M
a
rti
n
De
m
o
n
stra
tes
V
irt
u
a
l
M
a
i
n
ten
a
n
c
e
S
o
f
tw
a
re
.
Avia
ti
o
n
W
e
e
k
a
n
d
S
p
a
c
e
T
e
c
h
n
o
l
o
g
y
.
1
5
6
(
1
4
),
P
.
8
9
.
[7
9
]
Ru
f
fa
ld
i,
E.
,
F
il
i
p
p
e
sc
h
i,
A
.
,
Av
izz
a
n
o
,
C.
A
.
,
Ba
rd
y
,
B.
,
G
o
p
h
e
r,
D.,
&
Be
r
g
a
m
a
sc
o
,
M
.
(2
0
1
1
).
F
e
e
d
b
a
c
k
,
Aff
o
rd
a
n
c
e
s,
a
n
d
A
c
c
e
ler
a
to
rs
f
o
r
T
ra
in
in
g
S
p
o
r
ts
in
V
ir
tu
a
l
E
n
v
i
ro
n
m
e
n
ts.
Pre
se
n
c
e
:
T
e
leo
p
e
ra
to
rs
&
Vi
rtu
a
l
En
v
iro
n
me
n
ts
,
2
0
(1
)
,
3
3
-
4
6
.
[8
0
]
S
a
n
d
e
rs,
P
.
(2
0
1
0
),
B
o
e
in
g
7
8
7
T
ra
in
in
g
tak
e
s a V
irt
u
a
l
P
a
th
.
T
h
e
W
a
ll
S
tre
e
t
J
o
u
rn
a
l
.
[8
1
]
S
c
a
les
,
B.
(2
0
1
3
).
V
irt
u
a
l
Im
m
e
rsio
n
T
ra
in
i
n
g
:
Blo
o
d
les
s
Ba
tt
le
s
f
o
r
S
m
a
ll
Un
it
Re
a
d
in
e
ss
.
Ar
my
M
a
g
a
zin
e
,
6
3
(
7
),
2
4
-
27.
[8
2
]
S
e
o
,
J.
,
&
Kim
,
G
.
J.
(2
0
0
2
).
De
sig
n
f
o
r
P
re
se
n
c
e
:
A
S
tru
c
tu
re
d
A
p
p
ro
a
c
h
to
V
irt
u
a
l
Re
a
li
ty
S
y
s
tem
De
sig
n
.
Pre
se
n
c
e
:
T
e
leo
p
e
ra
to
rs
&
Vi
rtu
a
l
E
n
v
iro
n
me
n
ts
,
1
1
(4
)
,
3
7
8
-
4
0
3
.
d
o
i:
1
0
.
1
1
6
2
/1
0
5
4
7
4
6
0
2
7
6
0
2
0
4
2
9
1
.
[8
3
]
S
e
y
m
o
u
r,
N.E
.
,
G
a
ll
a
g
h
e
r,
A
.
G
.
,
&
S
a
tav
a
,
R.
M
.
(2
0
0
2
).
V
irt
u
a
l
Re
a
li
ty
T
ra
in
in
g
I
m
p
ro
v
e
s
o
p
e
ra
ti
n
g
Ro
o
m
P
e
rf
o
rm
a
n
c
e
.
An
n
a
ls
o
f
S
u
rg
e
ry
.
2
3
6
(4
),
4
5
8
-
4
6
4
.
[8
4
]
S
h
c
h
u
ro
v
,
I.
(2
0
1
1
).
Ca
lcu
latio
n
o
f
th
e
v
irt
u
a
l
p
it
c
h
th
re
a
d
d
ia
m
e
ter
u
sin
g
th
e
c
lo
u
d
o
f
p
o
i
n
ts
f
ro
m
CM
M
.
In
ter
n
a
t
io
n
a
l
J
o
u
r
n
a
l
o
f
A
d
v
a
n
c
e
d
M
a
n
u
f
a
c
tu
rin
g
T
e
c
h
n
o
lo
g
y
,
5
3
(
1
-
4
),
2
4
1
-
2
4
5
.
d
o
i:
1
0
.
1
0
0
7
/s0
0
1
7
0
-
0
1
0
-
2
8
1
5
-
z.
[8
5
]
S
h
e
y
-
Hu
e
i,
S
.
,
C
h
in
-
C
h
ih
,
C.
,
&
Ye
n
-
L
u
a
n
,
C.
(2
0
1
0
).
A
Ge
n
e
ra
li
z
e
d
P
e
rio
d
ic
P
re
v
e
n
ti
v
e
M
a
in
ten
a
n
c
e
M
o
d
e
l
W
it
h
V
irt
u
a
l
A
g
e
f
o
r
a
S
y
ste
m
S
u
b
jec
ted
t
o
S
h
o
c
k
s.
Co
mm
u
n
ica
t
io
n
s
I
n
S
t
a
ti
stics
:
T
h
e
o
ry
&
M
e
th
o
d
s
,
3
9
(1
3
),
2
3
7
9
-
2
3
9
3
.
d
o
i:
1
0
.
1
0
8
0
/
0
3
6
1
0
9
2
1
0
0
3
7
7
8
1
4
2
.
[8
6
]
S
p
it
e
ri,
A
.
V
.
,
A
g
g
a
r
w
a
l,
R.
,
Ke
rse
y
,
T
.
L
.
,
S
ira,
M
.
,
Be
n
jam
in
,
L
.
,
Da
rz
i,
A
.
W
.
,
&
Blo
o
m
,
P
.
A
.
(2
0
1
4
)
.
De
v
e
lo
p
m
e
n
t
o
f
a
v
irt
u
a
l
re
a
li
t
y
train
in
g
c
u
rric
u
lu
m
f
o
r
p
h
a
c
o
e
m
u
lsi
f
ica
ti
o
n
su
rg
e
r
y
.
Eye
,
2
8
(1
),
7
8
-
8
4
.
d
o
i
:
1
0
.
1
0
3
8
/ey
e
.
2
0
1
3
.
2
1
1
[8
7
]
S
u
m
it
a
n
i,
D.,
Eg
i,
H.,
T
o
k
u
n
a
g
a
,
M
.
,
Ha
tt
o
ri
,
M
.
,
Yo
sh
im
it
su
,
M
.
,
Ka
wa
h
a
ra
,
T
.
,
&
Oh
d
a
n
,
H.
(2
0
1
3
).
V
irt
u
a
l
re
a
li
t
y
train
in
g
f
o
ll
o
w
e
d
b
y
b
o
x
t
ra
in
in
g
im
p
ro
v
e
s
th
e
lap
a
ro
sc
o
p
ic
sk
il
ls
o
f
n
o
v
ice
su
rg
e
o
n
s.
M
in
ima
ll
y
In
v
a
siv
e
T
h
e
ra
p
y
&
Al
li
e
d
T
e
c
h
n
o
lo
g
ies
,
2
2
(3
),
1
5
0
-
1
5
6
.
d
o
i:
1
0
.
3
1
0
9
/1
3
6
4
5
7
0
6
.
2
0
1
2
.
7
2
1
3
7
7
.
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
,
Decem
b
er
201
6
:
2
6
9
8
–
2
7
0
7
2706
[8
8
]
S
u
m
m
e
rs,
J.E
.
,
S
im
u
latio
n
-
Ba
se
d
M
il
it
a
ry
T
ra
in
in
g
:
A
n
En
g
in
e
e
ri
n
g
A
p
p
ro
a
c
h
t
o
Be
tt
e
r
A
d
d
re
ss
in
g
Co
m
p
e
ti
n
g
En
v
iro
n
m
e
n
tal,
F
isc
a
l,
a
n
d
S
e
c
u
ri
ty
Co
n
c
e
rn
s.
J
o
u
rn
a
l
o
f
t
h
e
W
a
sh
in
g
t
o
n
Aca
d
e
my
o
f
S
c
ien
c
e
s
,
9
8
(
1
),
9
-
3
0
.
[8
9
]
S
u
n
,
S
.
,
&
T
sa
i,
L
.
(2
0
1
2
)
.
De
v
e
lo
p
m
e
n
t
o
f
v
irt
u
a
l
train
in
g
p
latf
o
r
m
o
f
in
jec
ti
o
n
m
o
ld
i
n
g
m
a
c
h
in
e
b
a
se
d
o
n
V
R
tec
h
n
o
l
o
g
y
.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
Ad
v
a
n
c
e
d
M
a
n
u
fa
c
t
u
rin
g
T
e
c
h
n
o
lo
g
y
,
6
3
(
5
-
8
),
6
0
9
-
6
2
0
.
d
o
i:
1
0
.
1
0
0
7
/s
0
0
1
7
0
-
0
1
2
-
3
9
3
8
-
1.
[9
0
]
S
u
n
,
Y.,
&
Z
h
a
n
g
,
W
.
(2
0
0
9
).
S
t
u
d
y
in
g
e
n
e
rg
y
-
o
rien
ted
d
y
n
a
m
i
c
o
p
ti
m
iza
ti
o
n
i
n
Ja
v
a
v
irt
u
a
l
m
a
c
h
in
e
s.
J
o
u
rn
a
l
o
f
Circ
u
it
s,
S
y
ste
ms
&
Co
mp
u
ter
s
,
1
8
(1
),
1
0
3
-
1
2
0
.
[9
1
]
T
h
il
m
a
n
y
,
J.
(2
0
0
1
).
A
u
to
c
e
n
ter
to
b
u
il
d
v
irt
u
a
l
re
a
li
ty
d
isp
lay
.
M
e
c
h
a
n
ica
l
En
g
i
n
e
e
rin
g
,
1
2
3
(1
0
),
2
6
-
38.
[9
2
]
T
h
o
rn
e
,
K.
(
2
0
0
5
)
.
De
sig
n
in
g
v
irt
u
a
l
o
rg
a
n
iza
ti
o
n
s?
T
h
e
m
e
s
a
n
d
tr
e
n
d
s
i
n
p
o
li
t
ica
l
a
n
d
o
rg
a
n
iza
ti
o
n
a
l
d
isc
o
u
rse
s.
T
h
e
J
o
u
r
n
a
l
o
f
M
a
n
a
g
e
me
n
t
De
v
e
lo
p
me
n
t,
24
(7
),
5
8
0
-
6
0
7
.
[9
3
]
T
sa
n
g
,
J.
S
.
,
Na
u
g
h
to
n
,
P
.
A
.
,
L
e
o
n
g
,
S
.
,
Hill
,
A
.
K.,
Ke
ll
y
,
C.
J.,
&
L
e
a
h
y
,
A
.
L
.
(2
0
0
8
).
V
irt
u
a
l
re
a
li
t
y
si
m
u
latio
n
e
n
d
o
v
a
sc
u
lar su
rg
ica
l
train
i
n
g
.
S
u
rg
e
o
n
(E
d
i
n
b
u
rg
h
Un
iv
e
rsity
P
re
ss
),
6
(4
)
,
2
1
4
-
2
2
0
.
[9
4
]
Tw
o
ru
s,
R.
,
S
z
y
m
a
n
sk
a
,
S
.
,
&
Il
n
ick
i,
S
.
(2
0
1
0
).
A
S
o
ld
ier
S
u
f
f
e
rin
g
f
ro
m
P
T
S
D,
T
re
a
ted
b
y
Co
n
tro
ll
e
d
S
tres
s
Ex
p
o
siti
o
n
Us
i
n
g
V
irt
u
a
l
Re
a
li
t
y
a
n
d
Be
h
a
v
io
ra
l
T
ra
in
in
g
.
Cy
b
e
rp
sy
c
h
o
lo
g
y
,
Beh
a
v
io
r
&
S
o
c
ia
l
Ne
two
rk
i
ng
,
1
3
(
1
),
1
0
3
-
1
0
7
.
d
o
i:
1
0
.
1
0
8
9
/cy
b
e
r.
2
0
0
9
.
0
3
2
9
.
[9
5
]
V
irt
u
a
l
c
o
m
b
a
t
in
a
c
tu
a
l
lab
.
(1
9
9
7
)
.
Civil
En
g
in
e
e
rin
g
,
6
7
(9
),
2
6
.
Re
tri
e
v
e
d
o
n
M
a
y
1
,
2
0
1
6
f
ro
m
h
tt
p
:
//
se
a
rc
h
.
p
r
o
q
u
e
st.co
m
.
a
th
e
n
s.ii
i.
c
o
m
/d
o
c
v
iew
/2
2
8
4
9
5
3
9
1
?
a
c
c
o
u
n
ti
d
=
8
4
1
1
[9
6
]
Vi
rtu
a
l
M
a
in
te
n
a
n
c
e
T
ra
in
e
r
Ai
r
b
u
s
A
3
2
0
.
(n
.
d
.
)
.
Re
tri
e
v
e
d
M
a
y
1
,
2
0
1
6
f
ro
m
f
ro
m
h
tt
p
s://
w
ww
.
s
w
iss
-
a
v
iatio
n
-
train
in
g
.
c
o
m
/en
/d
e
v
ice
s/v
irt
u
a
l
-
m
a
in
ten
a
n
c
e
-
train
e
r
-
a
irb
u
s
-
a
3
2
0
[9
7
]
V
irt
u
a
l
Re
a
li
ty
T
r
a
in
in
g
.
(1
9
9
9
).
US
A
T
o
d
a
y
M
a
g
a
zin
e
,
1
2
7
(2
6
4
5
)
,
3
.
[9
8
]
V
irt
u
a
l
Re
a
li
ty
f
o
r
a
v
i
a
ti
o
n
trai
n
in
g
:
T
h
e
IAT
A
De
mo
.
(2
0
1
5
,
M
a
rc
h
2
0
).
Re
tri
e
v
e
d
A
p
ril
3
,
2
0
1
6
,
f
ro
m
h
tt
p
:
//
ww
w
.
b
rig
h
tw
a
v
e
.
c
o
.
u
k
/o
u
r
-
th
in
k
in
g
/v
irt
u
a
l
-
re
a
li
ty
-
f
o
r
-
a
v
i
a
ti
o
n
-
trai
n
in
g
-
th
e
-
iata
-
d
e
m
o
/i
n
d
e
x
.
h
tm
l
[9
9
]
V
irt
u
a
l
Re
a
li
ty
f
o
r
so
ld
iers
,
c
o
p
s.
(1
9
9
5
).
T
h
e
Fu
t
u
rist,
2
9
(
6
),
4
4
.
Re
tri
e
v
e
d
o
n
A
p
ril
1
,
2
0
1
6
f
ro
m
:
h
tt
p
:
//
se
a
rc
h
.
p
r
o
q
u
e
st.co
m
.
a
th
e
n
s.ii
i.
c
o
m
/d
o
c
v
iew
/2
1
8
5
5
3
6
7
0
?
a
c
c
o
u
n
ti
d
=
8
4
1
1
[1
0
0
]
Vi
rtu
a
l
Rea
li
ty
M
e
d
ia
-
M
il
it
a
ry
Ai
rc
ra
ft
S
imu
la
ti
o
n
s
a
n
d
T
ra
in
i
n
g
S
y
ste
ms
.
(n
.
d
.
).
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:
//
ww
w
.
a
ir
f
o
rc
e
-
tec
h
n
o
lo
g
y
.
c
o
m
/co
n
trac
to
rs/train
in
g
/v
irt
u
a
l
-
re
a
li
ty
-
m
e
d
ia/
V
irt
u
a
l
Re
a
li
ty
P
re
p
a
re
s
S
o
ld
iers
f
o
r
Re
a
l
War.
(2
0
0
6
,
F
e
b
r
u
a
r
y
1
4
).
Re
tri
e
v
e
d
A
p
ril
3
,
2
0
1
6
,
f
ro
m
h
tt
p
:/
/w
ww
.
wa
sh
in
g
to
n
p
o
st.co
m
/w
p
-
d
y
n
/co
n
ten
t/
a
rti
c
le/2
0
0
6
/0
2
/
1
3
/A
R2
0
0
6
0
2
1
3
0
2
4
3
7
.
h
tm
l
[1
0
1
]
W
a
g
n
e
r,
R.
J.,
&
Ca
m
p
b
e
ll
,
J.
(1
9
9
4
).
Ou
t
d
o
o
r
-
b
a
se
d
e
x
p
e
rien
ti
a
l
train
in
g
:
Im
p
ro
v
in
g
tran
sfe
r
o
f
t
ra
in
in
g
u
sin
g
v
irt
u
a
l
re
a
li
ty
.
T
h
e
J
o
u
rn
a
l
o
f
M
a
n
a
g
e
me
n
t
De
v
e
lo
p
me
n
t,
13
(
7
),
4
-
15.
[1
0
2
]
W
h
o
W
e
Are
.
(n
.
d
.
).
Re
tri
e
v
e
d
f
ro
m
h
tt
p
:/
/www
.
c
a
e
.
c
o
m
/ab
o
u
t
-
c
a
e
/co
rp
o
ra
te
-
i
n
f
o
rm
a
ti
o
n
/w
h
o
-
we
-
a
r
e
/
[1
0
3
]
W
it
ten
b
e
rg
,
G
.
(1
9
9
5
)
.
T
ra
in
in
g
w
it
h
v
irt
u
a
l
re
a
li
ty
.
Asse
mb
ly A
u
to
ma
ti
o
n
,
15
(3
),
1
2
-
1
8
.
[1
0
4
]
Wy
c
h
e
,
L
.
D.
(2
0
1
4
).
T
ra
in
in
g
a
n
d
Ed
u
c
a
ti
o
n
M
u
st
L
e
v
e
r
a
g
e
T
e
c
h
n
o
l
o
g
y
a
n
d
In
n
o
v
a
ti
o
n
.
Army
S
u
sta
in
me
n
t
,
Re
tri
e
v
e
d
o
n
M
a
rc
h
1
5
,
2
0
1
6
f
ro
m
:
h
tt
p
:/
/0
-
w
e
b
.
b
.
e
b
sc
o
h
o
st.co
m
.
a
th
e
n
s.ii
i
.
c
o
m
/eh
o
st/d
e
t
a
il
/d
e
tail?v
id
=
8
0
&
sid
=
f
7
b
9
9
0
f
a
-
e
e
f
3
-
46be
-
8
e
d
c
-
8
a
5
9
3
d
b
0
b
f
1
6
%
4
0
se
ss
io
n
m
g
r1
1
4
&
h
i
d
=
1
0
9
&
b
d
a
ta=
Jn
Np
d
G
U9
ZW
h
v
c
3
Qtb
G
l2
ZQ%
3
d
%
3
d
#
d
b
=
f
5
h
&
A
N=
9
8
6
2
2
1
95
[1
0
5
]
X
ia,
P
.
,
L
o
p
e
s,
A
.
M
.
,
&
Re
stiv
o
,
M
.
T
.
(2
0
1
3
).
A
re
v
ie
w
o
f
v
irt
u
a
l
re
a
li
t
y
a
n
d
h
a
p
ti
c
s
f
o
r
p
ro
d
u
c
t
a
ss
e
m
b
l
y
(p
a
rt
1
):
Rig
id
p
a
rts.
Asse
mb
ly
Au
to
ma
ti
o
n
,
33
(
1
),
6
8
-
7
7
.
d
o
i:
h
tt
p
:/
/0
-
d
x
.
d
o
i
.
o
rg
.
a
th
e
n
s
.
ii
i.
c
o
m
/1
0
.
1
1
0
8
/0
1
4
4
5
1
5
1
3
1
1
2
9
4
7
8
4
[1
0
6
]
Yu
,
H.,
P
e
n
g
,
G
.
,
&
L
iu
,
W
.
(
2
0
1
1
).
A
p
ra
c
ti
c
a
l
m
e
th
o
d
f
o
r
m
e
a
su
rin
g
p
ro
d
u
c
t
m
a
in
tain
a
b
il
i
ty
in
a
v
irt
u
a
l
e
n
v
iro
n
m
e
n
t.
Asse
mb
ly
Au
t
o
ma
ti
o
n
,
31
(
1
),
5
3
-
6
1
.
d
o
i:
h
tt
p
:/
/
0
-
d
x
.
d
o
i
.
o
rg
.
a
th
e
n
s
.
ii
i.
c
o
m
/1
0
.
1
1
0
8
/0
1
4
4
5
1
5
1
1
1
1
1
0
4
1
7
3
[1
0
7
]
Yu
a
n
,
Z.
,
F
e
n
g
,
S
.
,
Yin
,
Q
.
,
W
a
n
g
,
X
.
,
Zh
a
n
g
,
D.,
Zh
a
o
,
J.,
&
Ch
e
n
,
M
.
(2
0
0
9
).
E
n
d
o
sc
o
p
ic
I
m
a
g
e
Cu
tt
in
g
S
im
u
latio
n
Ba
se
d
o
n
M
a
ss
-
S
p
r
in
g
M
o
d
e
l
a
n
d
C
o
m
p
u
tatio
n
a
l
G
e
o
m
e
tr
y
.
J
o
u
rn
a
l
o
f
Circ
u
it
s,
S
y
ste
ms
&
Co
mp
u
ter
s
,
1
8
(
8
),
1
4
5
3
-
1
4
6
5
.
[1
0
8
]
Zh
o
u
,
D.,
Ka
n
g
,
L
.
,
&
Ch
u
a
n
,
L
.
(2
0
1
3
).
A
v
irt
u
a
l
re
a
li
t
y
-
b
a
se
d
m
a
in
ten
a
n
c
e
ti
m
e
m
e
a
su
re
m
e
n
t
m
e
th
o
d
o
l
o
g
y
f
o
r
c
o
m
p
lex
p
ro
d
u
c
ts.
Asse
mb
ly
Au
t
o
ma
ti
o
n
,
33
(
3
),
2
2
1
-
2
3
0
.
d
o
i:
h
tt
p
:/
/0
-
d
x
.
d
o
i.
o
rg
.
a
th
e
n
s.ii
i.
c
o
m
/1
0
.
1
1
0
8
/A
A
-
12
-
2
0
1
3
-
0
4
8
B
I
O
G
RAP
H
I
E
S
O
F
AUTH
O
RS
K
o
u
r
o
u
s
h
J
e
n
a
b
is
a
se
n
io
r
m
e
m
b
e
r
o
f
IEE
E,
re
c
e
iv
e
d
th
e
B.
S
c
.
d
e
g
re
e
f
ro
m
th
e
IE
De
p
a
rtm
e
n
t
a
t
Isf
a
h
a
n
Un
iv
e
rsit
y
o
f
T
e
c
h
n
o
lo
g
y
(1
9
8
9
)
,
th
e
M
.
S
c
.
d
e
g
re
e
f
ro
m
th
e
IE
De
p
a
rtm
e
n
t
a
t
T
e
h
ra
n
P
o
ly
tec
h
n
ic
(1
9
9
2
),
a
n
d
th
e
P
h
.
D
.
d
e
g
re
e
f
ro
m
th
e
De
p
a
rt
m
e
n
t
o
f
M
e
c
h
a
n
ica
l
En
g
in
e
e
rin
g
a
t
t
h
e
Un
iv
e
rsit
y
o
f
Otta
wa
(2
0
0
5
).
He
se
r
v
e
d
a
s
a
se
n
io
r
e
n
g
in
e
e
r/
m
a
n
a
g
e
r
in
a
u
to
,
a
n
d
h
ig
h
-
tec
h
in
d
u
stries
f
o
r
1
8
y
e
a
rs.
He
jo
in
e
d
th
e
Na
ti
o
n
a
l
Re
se
a
rc
h
Co
u
n
c
il
Ca
n
a
d
a
a
s
a
re
s
e
a
rc
h
o
ff
ice
r
w
h
e
re
h
e
p
a
rti
c
ip
a
ted
in
se
v
e
r
a
l
in
tern
a
ti
o
n
a
l
re
se
a
rc
h
p
ro
jec
ts.
In
2
0
0
6
,
h
e
j
o
in
e
d
th
e
De
p
a
rtme
n
t
o
f
M
e
c
h
a
n
ica
l
a
n
d
In
d
u
strial
En
g
in
e
e
rin
g
a
t
R
y
e
rs
o
n
Un
iv
e
rsity
,
T
o
ro
n
to
a
s
a
n
a
ss
istan
t
p
ro
f
e
ss
o
r.
Cu
rre
n
tl
y
,
Dr
.
Je
n
a
b
is
a
f
a
c
u
lt
y
m
e
m
b
e
r
o
f
F
a
c
u
lt
y
o
f
Co
ll
e
g
e
o
f
Bu
sin
e
ss
,
A
th
e
n
s
S
tate
Un
iv
e
rsit
y
,
A
th
e
n
s,
AL
,
USA
.
He
h
a
s
p
u
b
li
s
h
e
d
o
v
e
r
1
0
0
p
a
p
e
rs
i
n
i
n
tern
a
ti
o
n
a
l
sc
ien
ti
f
ic j
o
u
rn
a
ls
b
a
se
d
o
n
h
is
e
x
p
e
rien
c
e
s in
i
n
d
u
stries
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2088
-
8708
V
ir
tu
a
l Ma
in
ten
a
n
ce
,
R
e
a
lity,
a
n
d
S
ystems
:
A
R
ev
iew
(
K
o
u
r
o
u
s
h
Je
n
a
b
)
2707
S
a
e
id
M
o
sle
h
p
o
u
r
is
a
F
u
ll
P
ro
f
e
ss
o
r
in
th
e
El
e
c
tri
c
a
l
a
n
d
Co
m
p
u
ter E
n
g
in
e
e
rin
g
De
p
a
rtm
e
n
t
in
th
e
Co
ll
e
g
e
o
f
En
g
in
e
e
rin
g
,
T
e
c
h
n
o
lo
g
y
,
a
n
d
A
rc
h
it
e
c
tu
re
a
t
th
e
Un
iv
e
rsit
y
o
f
H
a
rtf
o
rd
.
He
h
o
l
d
s
P
h
.
D.
(1
9
9
3
)
f
ro
m
Io
w
a
S
tate
Un
iv
e
rsity
a
n
d
Ba
c
h
e
lo
r
o
f
S
c
ien
c
e
(1
9
8
9
)
a
n
d
M
a
ste
r
o
f
S
c
ien
c
e
(1
9
9
0
)
d
e
g
re
e
s
f
ro
m
Un
iv
e
rsit
y
o
f
Ce
n
tral
M
isso
u
ri.
His
r
e
se
a
rc
h
in
tere
sts
in
c
lu
d
e
lo
g
ic
d
e
sig
n
,
C
P
L
Ds
,
F
P
GA
s,
Em
b
e
d
d
e
d
e
lec
tro
n
ic sy
ste
m
tes
ti
n
g
a
n
d
d
istan
c
e
lea
rn
in
g.
S
a
m
K
h
o
u
r
y
is
c
u
rre
n
tl
y
th
e
Co
o
rd
i
n
a
to
r
o
f
th
e
Co
m
p
u
ter
In
f
o
rm
a
ti
o
n
S
y
ste
m
s
Co
n
c
e
n
tratio
n
in
t
h
e
Div
isio
n
o
f
Bu
si
n
e
ss
a
t
S
p
rin
g
Hill
Co
l
leg
e
.
He
e
a
rn
e
d
h
is
AA
S
in
lo
g
isti
c
s
f
ro
m
th
e
Co
m
m
u
n
it
y
Co
ll
e
g
e
o
f
th
e
A
ir
F
o
rc
e
,
BA
S
in
b
u
si
n
e
ss
a
d
m
in
istratio
n
f
ro
m
th
e
Un
iv
e
rsit
y
o
f
M
o
u
n
t
Oliv
e
,
M
S
A
in
g
e
n
e
ra
l
a
d
m
in
istratio
n
f
ro
m
C
e
n
tral
M
ich
ig
a
n
Un
iv
e
rsity
,
a
n
d
h
is
P
h
.
D.
i
n
o
rg
a
n
iza
ti
o
n
a
n
d
m
a
n
a
g
e
m
e
n
t
f
r
o
m
Ca
p
e
ll
a
Un
iv
e
rsit
y
.
He
h
a
s
o
v
e
r
2
9
y
e
a
rs
o
f
e
x
p
e
rien
c
e
in
in
f
o
rm
a
ti
o
n
tec
h
n
o
l
o
g
y
a
n
d
is
th
e
f
o
rm
e
r
f
o
u
n
d
e
r
a
n
d
p
re
si
d
e
n
t
o
f
S
A
M
IR
S
y
ste
m
s,
In
c
.
,
a
p
riv
a
tel
y
h
e
ld
c
o
m
p
a
n
y
sp
e
c
ializin
g
in
a
c
a
d
e
m
ic
so
f
t
w
a
r
e
d
e
v
e
lo
p
m
e
n
t
a
n
d
su
p
p
o
rt
.
He
h
a
s
p
u
b
li
sh
e
d
e
x
ten
siv
e
l
y
in
th
e
a
re
a
s
o
f
lo
g
isti
c
s,
o
rg
a
n
iza
ti
o
n
d
e
v
e
lo
p
m
e
n
t,
in
f
o
r
m
a
ti
o
n
tec
h
n
o
l
o
g
y
,
a
n
d
a
u
to
m
a
ti
o
n
o
f
a
c
a
d
e
m
ic
p
ro
c
e
ss
e
s.
He
h
a
s
a
l
so
m
a
n
a
g
e
d
th
e
d
e
v
e
lo
p
m
e
n
t
a
n
d
im
p
le
m
e
n
tatio
n
o
f
n
u
m
e
ro
u
s so
f
tw
a
r
e
s
y
ste
m
s.
Evaluation Warning : The document was created with Spire.PDF for Python.