In
te
r
n
ation
a
l Jou
rn
al
o
f Po
we
r
Elec
tron
ic
s an
d
D
r
ive S
y
stem
(IJ
PED
S
)
V
o
l.
10, N
o.
4, D
e
c
e
m
ber
201
9,
pp.
2206~
22
13
ISSN: 2088-
8694,
DOI
:
10.11591
/ijpeds.
v10.
i
4.pp2206-2213
2
2
06
Jou
rn
a
l
h
o
me
pa
ge
:
ht
tp:
//i
a
e
score
.
com
/
j
o
u
r
na
l
s
/
i
n
d
e
x
.
p
hp/IJ
PED
S
Solar energy density
estimation
using
ANFIS based on da
ily
maximum and minimum temp
erature
M. Irw
an
to
1,2
,
H
.
A
l
a
m
1
,
M
.
M
asri
1
, B.
Ismai
l
2
,
W
.
Z
.
L
e
ow
2
,
Y
.
M
.
I
r
w
a
n
3
1
Departement
of E
l
ectrical Eng
i
n
eering,
Institu
t
Teknologi
M
edan
(ITM),
Indonesia
2
F
e
ll
o
w
o
f cen
ter o
f
Ex
cell
e
nce fo
r Renewab
l
e Energ
y
, S
s
c
ho
o
l
o
f
Elect
rical
S
y
s
tem
En
g
i
neerin
g, Un
i
versit
i M
a
l
a
ys
ia
Perl
is
(UniMAP),
Ma
l
aysia
3
Centre
f
or
Diploma S
t
udies,
Univ
ersi
ti
M
a
l
a
ysia
Perlis (UniMA
P
)
,
Ma
laysia
Art
i
cl
e In
fo
ABSTRACT
A
r
tic
le hist
o
r
y
:
Re
ce
i
v
e
d
A
pr 21,
2
0
1
9
Re
vise
d Ju
n 1
2
,
2019
A
c
c
e
pte
d
J
u
l
3
,
2019
Th
e
d
a
ta
o
f
so
la
r
energ
y
d
en
sit
y
i
n
o
n
e
area
i
s
v
e
r
y
im
po
rtan
t
w
h
e
n
t
h
e
a
r
e
a
will
c
onstru
c
ted
ph
oto
v
o
l
t
a
ic
(
PV)
s
y
stem
.
T
h
e
d
a
t
a
i
s
as
p
reli
mi
nary
s
tu
dy
to
d
ecide
w
h
a
t
the
a
r
ea
is
s
u
i
t
a
ble
or
not
t
o
be
c
o
n
st
ruct
ed
t
h
e
P
V
a
p
p
l
i
cati
on
sy
st
e
m
.
But,
s
om
etim
e
th
e
av
a
i
lab
l
e
data
i
s
mi
ssing
b
ecaus
e
t
h
e
limitation
of
weat
her
eq
ui
pment
.
A
n
altern
a
t
iv
e
tech
ni
qu
e
f
o
r
t
h
e
a
v
ail
a
b
l
e
d
at
a
of
s
ol
ar
energ
y
d
ens
i
t
y
s
ho
ul
d
b
e
d
one
f
or
t
he
c
on
tin
uity
o
f
P
V
a
p
p
l
i
ca
t
io
n
sy
ste
m
deci
si
on.
A
n
es
tim
a
ti
on
tech
ni
que
o
f
so
lar
e
n
ergy
d
ensi
ty
i
s
on
e
part
o
f
go
od
a
l
te
rn
a
t
iv
e
to
s
ol
ve
t
h
i
s
p
r
ob
le
m.
T
hi
s
pa
p
e
r
p
r
e
s
e
n
ts
t
he
e
st
i
m
a
tion
o
f
s
o
l
ar
energ
y
d
ensi
ty
u
s
i
n
g
A
d
a
p
ti
ve
N
eur
o
n
F
u
z
z
y
I
n
fere
nc
e
S
y
stem
(AN
F
IS).
T
he
ANF
IS
s
yste
m
has
t
w
o
in
put
d
at
a
o
f
t
he
m
eas
ured
d
a
il
y
m
i
nim
u
m,
m
ax
im
um
t
e
m
peratu
re
a
n
d
d
i
f
f
e
rence
bet
w
een
m
axi
m
u
m
a
nd
m
i
nim
u
m
te
m
p
e
r
at
ure.
T
h
e
m
easu
r
ed
s
ol
ar
e
nerg
y
d
e
ns
it
y
is
a
s
ta
rget
d
ata
of
AN
FIS
sys
t
em
.
Th
e
dat
a
i
s
re
co
rded
f
rom
M
e
d
a
n
m
e
t
e
oro
l
ogical
s
tation
th
rou
gh
th
e
w
e
b
sit
e
o
f
w
o
rld
weath
e
r
on
li
ne
f
or
t
he
y
ear
o
f
2
0
18.
The
resul
t
sh
ow
s
t
h
at
t
h
e
a
v
e
rage
e
s
tim
at
ed
s
ol
ar
e
nerg
y dens
it
y
i
s
clas
s
i
f
i
e
d
in
th
e
very
hi
gh
s
olar
e
n
e
rg
y
dens
it
y
an
d
based
on
t
h
e
p
erc
e
n
t
ag
e
error
s
h
o
ws
t
h
a
t
the
est
i
m
a
ted
s
o
lar
e
n
ergy
den
si
ty is
acc
ept
a
ble
.
K
eyw
ord
s
:
S
o
lar
ene
r
gy d
e
nsit
y
Mi
ni
mu
m t
e
mp
erat
u
r
e
Maximum
temperature
ANFI
S
Co
pyri
gh
t © 2
019 In
stit
u
t
e
of Advanced
En
gi
neeri
n
g
an
d
S
c
ien
ce.
All
rights
res
e
rv
ed.
Corres
pon
d
i
n
g
Au
th
or:
M
.
I
r
w
an
t
o
,
D
e
pa
rtem
ent o
f
E
lectr
i
c
a
l E
n
gi
nee
r
in
g,
Inst
i
t
u
t
Te
k
nol
og
i Me
da
n (I
TM),
52 G
e
d
ung
A
r
c
a
Roa
d,
Meda
n
, 202
1
7
,
Indo
nes
i
a.
Em
ail:
mhd-ir
w
a
nt
o@
itm
.a
c.id
; irw
a
n
t
o
@
u
n
i
m
ap.
e
d
u
.m
y
1.
I
N
TR
OD
U
C
TI
O
N
S
o
lar
i
s
f
us
i
o
n
ra
d
i
a
t
i
o
n
pr
oc
ess
of
t
he
s
un
w
h
ic
h
its
l
a
y
e
r
c
a
n
be
d
iv
i
d
e
d
b
y
tw
o
pa
rts.
T
he
y
a
r
e
in
ner
an
d
ou
t
e
r
l
a
yer.
T
he
o
ut
er
l
aye
r
i
s
c
o
o
l
er
t
ha
n
t
h
e
inn
e
r
l
ay
e
r
.
Th
e
ou
t
e
r
l
a
y
e
r
o
f
s
un
p
ro
du
c
e
s
radi
ati
o
n
and it
pe
ne
tra
t
es
t
he
e
x
t
ra
-terr
e
strial
a
n
d
a
tm
osp
h
ere
r
e
gi
on
a
nd
ar
rives
the
surfa
c
e
of ea
r
th
[
1].
The so
l
a
r
ca
n
di
vide
d
by
so
l
a
r
pow
er
den
si
t
y
i
n un
i
t
of
W/
m
2
a
n
d
sol
a
r
e
n
e
r
gy
d
en
sit
y
i
n
uni
t
of
W
h/
m
2
or
kJ/m
2
or
MJ
/
m
2
.
The
s
o
lar
pow
er
d
e
n
sit
y
o
r
sola
r
e
n
er
gy
de
n
s
it
y
is
v
er
y
i
m
po
r
t
a
nt
t
o
de
term
ine
the
pe
rform
ance
(
vo
ltage
,
c
u
rre
n
t
an
d
power)
o
f
p
ho
to
vo
lt
ai
c
(P
V)
m
o
d
ul
e.
T
h
e
h
i
gher
s
o
l
a
r
pow
er
d
en
si
ty
o
r
so
la
r
ene
r
gy
de
ns
it
y
w
i
l
l
gene
ra
ted
the
hig
h
e
r
v
o
l
tage,
cur
r
ent
a
nd
p
o
w
e
r
of
P
V
mod
u
le
.
I
n
v
erse
ly
,
t
h
e
lo
we
r
sol
a
r
p
o
w
er
d
e
n
si
ty
o
r
so
l
a
r e
n
ergy
de
ns
ity
w
ill
ge
ne
ra
ted t
h
e
low
e
r
volta
ge
,
curr
e
n
t
a
nd
p
o
w
e
r
of
P
V mod
u
le.
The
e
f
f
ect
o
f
s
o
l
a
r po
w
e
r
densit
y
or so
l
ar
e
n
e
rgy de
nsit
y o
n
th
e
p
e
rfo
rman
c
e
o
f
P
V
mo
du
l
e
h
as
b
ee
n
stud
y
by
[
2],
the
performa
n
c
e
o
f
P
V
m
odu
le
i
ncr
e
a
s
e
s
o
n
t
h
e
c
o
n
d
i
tio
n
of
c
o
n
st
a
n
t
t
e
mpe
r
at
ure
an
d
th
e
i
n
c
r
ea
si
ng
o
f
so
l
a
r
p
o
w
e
r
d
en
si
ty
o
r
solar
energy
d
e
n
s
ity.
It
m
e
a
ns
t
ha
t
th
e
perf
orm
a
n
c
e
of
P
V
m
o
d
u
le
i
s
pro
port
i
ona
l
to
t
he
s
ola
r
p
ow
er
d
ens
i
t
y
o
r
solar
e
n
ergy
de
ns
it
y
.
The
incr
e
a
si
ng
o
f
t
h
e
per
f
orm
a
nc
e
o
f
P
V
modu
le
r
ela
t
ed
t
o
the
s
o
lar
p
o
w
e
r
d
ensi
ty
o
r
so
lar
e
n
ergy
d
e
ns
i
t
y
h
a
s
b
e
e
n
s
t
u
d
i
e
d
b
y
[
3
]
i
n
s
i
n
g
l
e
a
x
i
s
s
o
l
a
r
t
r
a
c
ki
ng
a
nd
[
4]
i
n
th
e
t
w
o
a
x
i
s
s
ol
a
r
t
ra
c
k
i
n
g
.
T
h
e
p
e
r
fo
rman
c
e
o
f
P
V
mo
d
u
l
e
i
n
t
h
e
t
w
o
ax
i
s
s
ol
ar
t
ra
ck
i
n
g
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
So
l
a
r ene
r
gy
d
e
n
s
ity
est
i
m
a
t
i
on us
i
n
g ANFI
S bas
ed
o
n
d
a
i
l
y
m
a
x
i
m
u
m
an
d m
i
n
i
m
u
m
…
(
M
. Irwa
nt
o)
2
207
is
b
e
t
ter
tha
n
i
n
t
h
e
sing
le
a
xi
s
so
lar
tra
c
ki
ng.
I
t
is
due
t
o
the
so
lar
po
w
e
r
de
nsity
o
r
solar
e
n
erg
y
d
en
s
i
t
y
ca
ptur
ed
b
y
tw
o
a
x
i
s
s
o
l
a
r
t
ra
c
k
in
g
i
s
h
i
ghe
r
com
p
ar
ed
t
o
t
h
e
s
i
ngl
e
axi
s
s
ol
ar
t
rac
k
i
n
g
.
T
h
e
a
d
v
a
nt
ag
e
s
o
f
sol
a
r
p
o
w
e
r
d
e
n
si
ty
o
r
sol
a
r
en
e
r
gy
d
en
sit
y
i
n
th
e
app
l
i
cati
o
n
s
o
f
P
V
m
od
ule
ha
ve
r
e
a
l
i
z
e
d
in
t
he
s
olar
w
a
t
e
r
pump
[5]
,
s
ola
r
P
V
pow
ere
d
i
n
v
er
t
e
r
[6-1
3
]
.
The
syst
e
m
s
a
r
e
ene
rgized
d
ire
c
t
l
y
by
P
V
m
odule
an
d
the
i
r
opera
tio
n
depe
nd
on
t
h
e so
lar
pow
er
densi
t
y
or
sol
a
r e
n
ergy
d
en
s
ity.
A
so
l
a
r
P
V
s
y
s
tem
i
s
v
e
r
y
d
e
pe
n
d
o
n
t
he
s
ol
a
r
p
ow
e
r
d
e
n
sit
y
o
r
sol
a
r
en
e
r
gy
d
e
n
si
ty
i
n
on
e
are
a
.
The
s
o
lar
p
o
w
e
r
dens
ity
o
r
solar
e
n
ergy
d
e
ns
i
t
y
s
h
o
u
l
d
b
e
m
ea
su
red
t
o
o
b
t
a
i
n
i
t
s
po
t
e
ntia
l
to
d
e
v
e
l
o
p
s
o
l
ar
P
V
s
yst
e
ms
[
1
4
-2
0].
Bu
t,
i
t
is
due
t
o
th
e
l
i
m
i
t
a
t
i
on
o
f
w
eat
h
e
r
m
ea
surem
e
n
t
e
qu
i
p
m
e
n
t
or no
e
q
u
i
pm
en
t,
t
hu
s
it
has
m
i
ss
in
g
data
o
f
s
o
lar
p
o
w
e
r
dens
i
t
y
or
s
olar
e
nergy
den
s
it
y
i
n
t
he
a
re
a.
S
om
e
t
e
chn
i
que
s
or
m
e
t
ho
ds
have
b
e
e
n
dev
e
l
o
pe
d
to
e
st
i
m
ate
the
so
lar
pow
e
r
d
en
si
ty
o
r
sola
r
ener
g
y
de
ns
i
t
y
i
n
o
ne
a
re
a
.
A
c
om
bina
t
i
on
Ha
rg
re
av
e
s
m
et
h
o
d
and
l
i
n
e
ar
r
eg
re
ssi
on
h
a
s
b
e
e
n
c
on
du
ct
ed
b
y
[
21
]
to
e
st
i
m
at
e
th
e
so
l
a
r
e
n
erg
y
d
e
nsit
y
in
P
e
rli
s
,
N
o
rther
n
M
a
l
ay
si
a
.
T
he
e
s
t
ima
t
e
d
s
o
l
a
r
e
ne
rg
y
de
ns
ity
i
s
c
o
mpa
r
ed
t
o
t
h
e
m
e
a
s
ur
ed
s
o
l
ar
e
nerg
y
den
s
i
t
y an
d val
i
d
a
te
d
u
s
i
n
g
t
h
e st
a
t
i
s
t
i
ca
l ana
l
y
s
is o
f perc
en
t
age er
ror.
T
he Ha
r
grea
ves
m
e
t
h
o
d
is als
o
a
ppl
ie
d
to
e
st
i
m
ate
so
l
a
r
ene
r
gy
den
s
ity
i
n
Me
da
n,
N
or
t
h
S
um
ater
a
,
I
ndo
nesi
a
[22].
The
result
shows
that
M
edan
i
s
ca
t
e
g
o
rize
d
i
n
a
v
ery
h
i
g
h
s
ol
a
r
e
ner
gy
de
nsit
y
a
nd
has
g
o
od
po
te
n
tia
l
t
o
d
e
v
e
l
op
P
V
a
pp
l
i
cat
i
o
n
sys
t
em
s.
A
mode
rn
t
ec
hni
que
i
s
a
l
s
o
a
p
p
lie
d
in
t
he
e
s
t
im
at
i
o
n
o
f
s
o
l
ar
e
ne
rg
y
us
i
n
g
d
i
gi
ta
l
nu
m
e
rica
l
b
y
[
2
3
].
T
his
tech
n
i
q
u
e
deve
l
o
pe
d
c
o
mp
u
t
a
t
i
o
nal
me
th
od
t
o
e
st
i
m
ate
the
po
te
nt
ia
l
o
f
s
ol
a
r
e
ner
gy
de
nsit
y
Eas
t
ern
G
o
ng
j
u
,
S
out
h
K
o
re
a.
M
a
t
he
ma
tic
a
l
m
ode
ll
in
g
o
f
e
st
ima
t
e
d
s
o
l
a
r
e
ner
g
y
d
ens
ity
i
s
a
p
pl
i
e
d
b
y
[
2
4
]
an
d
i
t
p
redic
t
t
he
ou
tpu
t
v
olta
ge
o
f
P
V
m
odul
e
.
A
rti
f
i
c
ia
l
In
te
ll
ig
en
t
(A
I)
t
e
c
hn
i
que
o
f
f
u
z
z
y
log
i
c
i
s
a
p
p
l
i
e
d
t
o
est
i
m
a
te
t
he
so
l
a
r
ene
r
gy
den
s
i
t
y
ba
se
d
on
t
h
e
m
e
te
oro
l
o
g
i
cal
p
a
r
am
eter
by
[
2
5
].
T
he
l
at
itu
de
,
lo
ng
itu
de
a
ng
l
e
,
tem
p
era
t
ur
e a
nd m
ean
s
un sh
i
n
e a
r
e
appl
ied i
n
t
he
fuz
z
y
lo
g
i
c
t
o
o
b
t
a
i
n
t
h
e
e
s
t
i
m
a
te
d
so
la
r
e
n
ergy
d
e
ns
it
y.
Th
is
p
a
p
e
r
p
re
sen
t
s
the
so
l
a
r
ene
r
gy
de
ns
i
t
y
est
i
ma
tio
n
u
s
i
n
g
A
da
pt
ive
N
e
ur
on
F
uzz
y
I
nfe
r
enc
e
S
y
stem
(
A
N
F
I
S
)
b
ase
d
on t
h
e
da
il
y
ma
xi
m
u
m
a
nd
m
i
ni
m
u
m
tem
p
er
at
u
re
.
Th
e
me
as
u
r
e
d
d
at
a
of
s
ol
a
r
e
n
e
rgy
den
s
i
t
y,
m
axi
m
um
a
nd
m
i
ni
m
u
m
tem
p
era
t
ure
a
r
e
co
ll
e
c
t
ed
f
r
o
m
Me
d
a
n
m
e
t
e
o
ro
lo
g
i
c
a
l
s
t
at
i
o
n
t
h
ro
ug
h
t
h
e
w
e
b
si
te
o
f
w
o
rld
w
e
a
t
he
r
on
li
ne.
T
h
r
ee
est
i
m
a
tio
n
c
o
n
d
iti
on
a
r
e
c
o
nd
uc
t
e
d
as
t
ra
i
n
i
n
g
of
A
N
F
IS
.
The
fi
r
s
t
con
d
i
t
i
on
is
m
inim
um
t
em
per
a
ture,
m
a
ximu
m
tem
p
era
t
u
r
e
a
n
d
so
lar
e
ner
gy
de
nsit
y,
t
h
e
s
econ
d
c
ond
i
t
io
n
i
s
ma
ximum
tem
p
er
at
ure,
t
he
d
i
f
fere
nce
bet
w
ee
n
m
a
xim
u
m
a
nd
m
i
n
i
m
u
m
t
e
m
pe
rat
u
re
a
nd
s
o
l
a
r
e
nerg
y
den
s
i
t
y,
t
he
t
h
i
rd
c
ond
i
t
i
on
i
s
t
he
m
i
n
imu
m
t
em
pera
t
u
r
e
,
the
d
i
ffere
n
c
e
be
tw
e
e
n
ma
ximum
a
n
d
mi
nim
u
m
t
e
mp
e
r
at
u
r
e
and
sol
a
r
en
e
r
gy
d
e
n
s
it
y
.
T
h
e
e
sti
m
at
e
d
a
n
d
m
ea
su
re
d
sola
r
e
n
e
r
gy
de
nsi
t
y
ar
e
va
lida
t
e
d
u
sing
st
a
t
i
s
t
i
ca
l
anal
ys
is
o
f
relat
i
ve
p
e
r
c
e
n
t
age
err
o
r.
2.
RESEARCH
M
ETH
O
D
Th
is
s
ec
t
i
o
n
d
i
s
c
u
sse
s
r
e
s
ear
ch
m
e
t
h
o
d
to
e
stim
ate
t
h
e
s
o
l
a
r
e
n
er
g
y
d
e
n
s
i
t
y
i
n
Me
da
n,
I
nd
on
e
s
i
a
.
L
o
c
a
ti
o
n
a
n
d
w
e
a
th
e
r
c
o
n
d
i
t
io
n
o
f
M
e
d
a
n
,
I
n
d
o
n
e
s
i
a
i
s
e
x
p
la
in
e
d
b
r
i
e
f
l
y
b
a
s
e
d
o
n
i
t
s
l
a
t
i
t
u
d
e
a
n
g
l
e
.
T
h
e
st
r
u
c
t
ure
of
A
N
F
IS
to
esti
m
a
te
t
he s
olar
ene
rgy de
nsi
t
y
is e
x
p
l
a
i
ne
d i
n
t
hi
s sec
t
i
on.
2.1
Loc
a
tion
of
Med
a
n
M
e
d
a
n
i
s
t
h
e
f
i
f
t
h
l
a
r
g
e
s
t
c
i
t
y
i
n
I
n
d
o
n
e
s
i
a
h
a
s
l
a
n
d
a
r
e
a
o
f
2
65.1
km
²
a
nd
i
t
i
s
loc
a
t
ed
on
the
lat
itu
de
o
f
3.5
8
0
N
a
s
s
h
ow
n
i
n
F
i
gure
1
[
22].
Me
da
n
ha
s
a
v
era
g
e
a
n
n
u
al
t
em
p
e
r
a
t
ur
e
o
f
26.4
o
C
a
n
d
it
i
s
rela
tive
ho
t
be
ca
use
i
t
i
s
i
n
t
he
e
qua
t
o
r
li
n
e
.
Medan
ha
s
go
o
d
p
o
t
e
n
tia
l
to
b
e
c
o
nstr
u
c
ted
PV
s
yste
m
as
repor
t
e
d by
[2
2].
F
i
gure
1.
L
ocat
io
n o
f
M
eda
n
,
Ind
one
sia
[22]
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
: 208
8-
869
4
I
nt
J
P
ow
Elec
& Dr
i
S
y
st V
ol.
10,
N
o.
4
, Dec
201
9 : 2
2
0
6
–
22
13
2
208
2.2
A
N
F
IS
s
ystem
as est
i
m
a
t
or
o
f
sol
a
r e
n
e
r
gy d
e
n
s
i
t
y
A
N
F
IS
i
s
hy
b
r
i
d
a
r
t
i
f
ic
i
a
l
i
n
te
l
l
i
g
e
n
t
s
y
st
e
m
t
ha
t
it
c
o
m
b
i
n
e
s
t
h
e
al
g
o
r
i
t
h
m
o
f
arti
fi
ci
a
l
n
eu
ra
l
netw
ork
(A
N
N
)
and
f
u
zz
y
i
n
fe
renc
e
sys
t
e
m
(
FIS
)
[
2
6
]
.
T
h
e
o
b
j
e
c
t
o
f
A
N
F
I
S
i
s
t
o
e
n
h
a
n
c
e
t
h
e
c
a
p
a
b
i
l
i
t
y
o
f
con
t
ro
l
l
er
o
r
esti
m
a
t
o
r
sys
t
e
m
b
ase
d
on t
h
e
p
r
e
v
ious data.
T
he
o
p
e
r
at
io
n
o
f
A
NF
IS
f
oll
o
w
s
a
f
uzzy
c
on
tr
ol
l
e
r
of
T
a
k
a
g
i-S
u
g
e
no
[27].
The
struc
t
ure
of
A
N
F
IS
c
onsi
s
ts
o
f
t
h
re
e
p
art
s
(
i
n
pu
t
d
a
t
a
,
p
r
oce
ss
a
n
d
ou
tput
d
at
a
)
as show
n
in
F
igure
2.
F
i
gure
2.
A
NF
IS
struct
u
re
usi
ng
f
uz
z
y
c
ontr
o
l
l
er
of
Taka
g
i
-S
uge
no
[27
]
The
struc
t
ure
of
A
N
F
IS
c
on
sis
t
s
of
f
ive
la
yers,
e
ach
l
a
y
er
i
s
c
o
n
s
t
ruct
ed
b
y
s
o
m
e
n
ode
s
as
n
o
d
e
fu
nc
ti
o
n
.
The func
t
i
o
n
o
f e
a
c
h
layer
is e
x
p
l
a
i
ne
d be
low
foll
ow
i
ng F
i
gur
e
2.
a.
The
first
la
yer
(
L
ayer
1
)
i
s
a
s
fu
z
z
i
fica
t
i
o
n
l
a
y
er
.
The
inp
u
t
da
t
a
w
ill
b
e
bl
urre
d
by
t
h
i
s
la
ye
r
usin
g
membership function.
b.
The
sec
o
nd
l
a
y
er
(
l
a
yer
2)
i
s
a
s
p
rod
u
c
t
l
a
y
er
.
It
m
ul
ti
pli
e
s
t
h
e
p
re
vi
ous
i
n
put
d
at
a
perf
o
r
mi
ng
l
ogic
“
A
N
D
”
a
s a
firin
g
p
ow
e
r
.
The
multip
l
i
ca
ti
on
pr
ocess c
a
n
be
s
ta
t
ed
a
s in
E
q. (
1)
.
x
(
1
)
c.
The
th
i
r
d
la
ye
r
(La
y
e
r
3
)
i
s
a
s
n
o
rm
alize
d
p
r
o
c
e
ss.
I
t
norm
a
liz
e
s
t
he
f
iri
n
g
pow
e
r
.
The
de
term
ina
t
ion
of
norm
a
l
i
zat
i
on i
s
gi
v
en
by
Eq.
(2).
,
f
o
r
i
=
1
,
2
(
2
)
d.
The
for
t
h
layer
(Layer
4
)
is
a
s
de
fuzz
i
f
ing
laye
r.
T
he
d
e
s
ire
d
out
pu
t
d
a
ta
s
ho
u
l
d
be
s
et
by
the
ba
c
k
pro
p
aga
tio
n
ne
ura
l
n
e
t
w
o
rk
a
nd
i
t
ha
ve
t
o
m
a
tc
h
w
i
t
h
t
he
t
arge
t
d
a
t
a
.
T
he
d
e
t
e
r
m
i
na
t
i
on
o
f
de
fuzz
if
ing
is
g
iven by
Eq. (
3)
.
(3
)
e.
The
fi
fth la
ye
r (
L
ayer
5)
i
s
a
s ou
t
p
u
t
la
y
e
r
.
It
is a
ddin
g
t
he
p
r
e
v
ious
d
e
f
uzz
i
fi
ng.
The
w
e
a
t
he
r
d
a
ta
n
eede
d
i
n
the
r
e
sea
r
ch
a
r
e
m
in
imum
t
e
m
pe
rat
u
re
,
ma
xi
m
u
m
te
mpe
r
at
ure
an
d
s
o
lar
ene
r
g
y
d
e
n
sit
y
f
or
t
he
y
ea
r
of
2
0
18
c
o
l
l
ec
ted
from
M
e
d
an
m
e
t
eor
olo
g
i
c
a
l
s
t
a
t
i
o
n
th
ro
ugh
t
h
e
w
eb
s
it
e
of
w
o
rld
w
e
a
t
her
on
l
i
ne.
T
h
e
m
i
nim
u
m,
m
axim
um
t
em
per
a
ture
a
nd
the
d
i
f
f
e
r
en
ce
b
etwe
en
m
a
x
i
m
um
a
n
d
minim
u
m
tem
p
er
at
ure
a
r
e
in
pu
t
da
ta
o
f
A
N
FIS
syst
e
m
.
The
m
e
a
s
ure
d
solar
energy
d
ensity
i
s
as
t
arget
dat
a
.
There
are
t
h
r
e
e
in
p
u
t
da
ta
c
o
n
d
i
tio
n
as
s
how
n
in
F
igur
e
3(a
)
c
r
e
a
ted
by
M
A
TLA
B.
T
he
f
irst
c
on
d
i
t
i
on
i
s
f
or
ma
ximum
t
e
mpe
r
at
ure
an
d
min
i
mum
t
e
mpe
r
ature
,
t
he
s
ec
on
d
c
o
nd
i
t
i
o
n
i
s
f
o
r
ma
xi
m
u
m
tem
p
er
ature
a
nd
t
h
e
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
So
l
a
r ene
r
gy
d
e
n
s
ity
est
i
m
a
t
i
on us
i
n
g ANFI
S bas
ed
o
n
d
a
i
l
y
m
a
x
i
m
u
m
an
d m
i
n
i
m
u
m
…
(
M
. Irwa
nt
o)
2
209
di
ffe
re
nce
be
tw
e
e
n ma
xi
m
u
m
and m
i
n
i
m
u
m
t
e
mpe
r
ature
, the
th
i
rd c
on
d
i
t
i
on
i
s t
h
e mi
nimu
m
t
e
mp
era
t
u
r
e
a
nd
the d
i
ffere
n
ce
betwee
n m
a
xi
mu
m
an
d
mi
n
i
mu
m
t
e
mp
e
r
at
u
r
e
.
Eac
h
i
n
p
u
t
d
a
t
a
is
b
l
u
rre
d
to
b
e
t
h
re
e
b
l
ur
red
da
ta
a
s
show
n
i
n
F
ig
ure
3(b
)
.
Its
ob
j
e
c
t
i
v
e
i
s
t
o
as
s
i
g
n
the
d
i
ffere
nce
numbe
r
o
f
m
em
bershi
p
f
unc
t
i
o
n
i
n
the
fuzz
y
i
n
fer
ence
s
ystem
(FIS).
I
t
is
d
ue
t
o
each
i
nput
data
i
s
b
l
urr
e
d
to
b
e
thr
ee
da
ta
,
thus
F
IS
h
a
s
3
2
=
9
(
n
i
ne)
rule
s
as
s
how
n
in
F
i
g
u
r
e
3(b)
a
nd
(
c).
T
h
e
blur
red
in
put
d
a
t
a
i
s
p
r
o
cesse
d
fol
l
o
w
i
n
g
t
he
r
ule
by
A
N
F
IS
s
ystem
a
n
d
ge
ne
r
a
tes
a
n
o
u
t
pu
t
da
t
a
a
s
the
e
s
tim
ated
so
l
a
r e
n
ergy
de
ns
ity
a
s show
n
i
n
F
ig
ure
3(a
)
a
nd (b)
.
(a) F
u
z
z
y
l
o
g
i
c
desi
gner
(
b
) Mode
l
of n
e
u
ral ne
t
w
ork
(c
)
R
u
l
e
F
i
gure
3.
A
NFI
S
s
truc
t
u
re
i
n
MA
TLA
B
2.3
V
a
l
i
d
a
ti
on
o
f m
e
asu
r
ed
a
nd
e
st
imated
solar
e
n
e
rgy
d
e
n
s
i
t
y
The
m
e
a
s
ured
s
o
l
ar
e
ner
g
y
den
s
i
t
y,
R
mea
,
i
a
nd
est
i
m
a
te
d
so
lar
ene
r
g
y
d
ens
ity,
R
es
t
,
i
a
r
e
v
a
l
i
d
a
t
e
d
us
i
n
g
a
r
e
la
t
i
v
e
p
e
r
ce
n
t
a
g
e
e
rror,
e
i
n
pe
rce
n
t
give
n
by
E
q
.
(4)
[2
1].
The
val
u
e
of
r
e
l
a
tive
per
cen
tag
e
e
r
r
or
betw
ee
n
-
1
0%
t
o
+10%
i
n
d
i
c
a
te
s
th
a
t
t
he
e
st
ima
t
e
d
s
ol
ar
e
n
e
rgy
de
n
s
ity
i
s
ac
ce
pta
b
l
e
[
21]
.
The
me
an
perc
en
tage
er
r
or
i
s
define
d
as a
pe
r
ce
nt
a
g
e d
e
via
t
i
o
n
o
f
da
i
l
y
m
e
a
s
ured
a
nd e
s
tim
ated
s
ola
r
e
nergy
dens
ity.
%
,
,
,
(4)
3.
RESULT
S
A
N
D
ANALY
S
IS
Th
is
s
ec
tio
n
pr
esen
ts
a
nd
a
na
l
y
sis
the
re
su
l
t
s
o
f
s
olar
e
ne
rg
y
de
n
s
it
y
usi
n
g
A
N
FIS
syste
m
.
The
i
npu
t
and
t
a
rget
d
ata
ar
e
p
l
ot
te
d
a
n
d
a
n
a
l
yse
d
.
T
h
e
re
su
lts
o
f
e
s
t
i
m
a
ted
da
ta
a
re
i
n
t
erpr
et
ed
i
n
t
h
ree
sc
e
n
ar
i
o
s
base
d
on
t
h
e
in
p
u
t
da
ta.
The
firs
t
sc
enar
io
i
s
for
th
e
inpu
t
da
ta
o
f
mi
n
i
mu
m
an
d
m
a
x
i
mu
m
t
e
m
p
er
a
t
u
r
e,
t
h
e
s
e
c
ond
sc
e
n
ario
i
s
fo
r
t
h
e
inp
u
t
d
a
ta
o
f
m
i
ni
mu
m
t
e
mp
era
t
u
r
e
an
d
di
ffe
rence
betwee
n
m
a
ximum
an
d
minimum
tem
p
era
t
ur
e,
t
he
t
h
i
rd
s
c
e
na
rio
is
f
or
t
he
i
np
u
t
d
ata
of
m
a
x
imu
m
te
m
p
era
t
ur
e
an
d
d
i
ffere
nce
be
t
w
ee
n
ma
ximum
and
minimum
tem
p
er
at
ure.
E
ac
h
sce
n
ario
r
esu
lts
t
he
d
if
f
erence
p
rofile
o
f
estimat
e
d
s
o
lar
energy
den
s
i
t
y
w
ith
a
l
s
o d
i
ffe
r
enc
e
m
inimum
,
ma
ximum
a
nd ave
r
age
so
lar
e
ner
gy den
s
i
t
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
: 208
8-
869
4
I
nt
J
P
ow
Elec
& Dr
i
S
y
st V
ol.
10,
N
o.
4
, Dec
201
9 : 2
2
0
6
–
22
13
2
210
3.1.
Input
a
n
d
t
a
r
g
e
t
da
t
a
o
f A
N
FIS
s
y
st
em
F
i
gure
4
s
how
s
t
h
e
da
i
l
y
m
i
nimum
,
m
axi
m
um
a
nd
d
i
ffe
renc
e
be
tw
e
e
n
ma
xi
mu
m
an
d
m
i
ni
mu
m
tem
p
era
t
ur
e
fo
r
the
year
2
0
1
8
.
These
da
ta
i
s
use
d
a
s
i
n
pu
t
data
o
f
A
N
F
I
S
system
a
s
sh
ow
n
i
n
F
i
g
ure
3(a)
.
Every
da
ily
m
i
n
i
m
um
,
m
a
xi
mum
a
n
d
d
i
ffe
re
nce
b
e
tw
een
m
axim
um
a
n
d
m
inim
u
m
t
em
per
a
t
u
re
i
s
b
l
ur
red
to
be
t
hr
ee
dai
l
y
m
i
n
im
um,
m
a
xim
u
m
a
nd
differe
nce
betw
e
e
n
m
ax
im
um
and
m
i
n
i
mum
t
e
m
p
er
ature
wi
th
o
ne
tem
p
era
t
ur
e
an
d
t
h
e
ot
her
is
m
ult
i
p
lie
d
by
t
h
e
per
f
orm
i
n
g
lo
gic
AND.
T
h
i
s
p
r
o
c
ess
i
s
t
o
t
r
ain
t
h
em
t
o
th
e
targe
t
d
ata
o
f
m
ea
sured
sola
r
e
n
ergy
d
e
nsit
y
(F
igure
5).
F
i
gure
4.
I
npu
t
data
of
A
N
F
IS
s
y
s
tem
F
i
gure
5. Ta
r
get
data
o
f A
N
F
IS
system
The
me
asured
s
ola
r
e
n
e
rg
y
de
n
s
i
t
y
as
t
a
r
get
da
ta
i
n
F
i
gur
e
5
ha
s
t
h
e
m
i
nimum
,
m
a
x
i
m
um
a
nd
ave
r
age
s
o
lar
e
n
erg
y
d
ens
i
t
y
a
r
e
4
.07
M
J
/m
2
,
26.
0
6
M
J
/
m
2
a
nd
18.
09
MJ
/m
2
,
respec
tive
l
y.
T
he
a
ver
a
ge
s
o
l
a
r
e
n
ergy
d
en
sity
v
al
u
e
o
f
18
.0
9
M
J
/
m
2
is e
q
u
iv
a
l
en
t t
o
5.
0
3 k
W
h
/
m
2
. It is a
bove 4.
00 kWh
/
m
2
and class
i
fied
i
n
the
ver
y
h
i
gh
s
o
lar
e
n
er
gy
de
ns
it
y
[28].
It
m
e
a
ns
t
ha
t
M
e
dan,
I
nd
o
n
esia
h
as
g
oo
d
p
o
t
e
n
tia
l
f
o
r
deve
l
o
p
i
ng
a
PV
power
gen
e
r
ati
on sy
st
e
m
.
3.2.
Est
i
m
a
t
i
on
of
so
lar e
n
e
r
gy d
e
n
s
ity
The
es
t
i
m
a
ti
o
n
o
f
s
o
lar
ene
r
gy
de
nsi
t
y
i
s
sim
u
l
a
te
d
us
i
ng
MA
TLA
B
in
t
hr
ee
scen
a
r
ios
for
th
e
di
ffe
re
nce
inp
u
t
d
ata
of
A
N
F
IS
s
ystem
.
T
he
f
irs
t
s
c
e
n
ari
o
(
sc
en
ar
io
1
)
i
s
f
or
t
he
i
n
p
u
t
da
ta
o
f
mi
n
i
mum
a
n
d
ma
ximum
tem
p
er
at
ure,
t
he
s
ec
o
n
d
sce
n
a
r
i
o
(
sc
enar
i
o
2
)
i
s
f
or
t
h
e
i
npu
t
d
a
t
a
o
f
minimu
m
t
e
mp
e
r
a
t
u
r
e
a
nd
di
ffe
re
nce
be
t
w
e
e
n
m
a
ximu
m
a
nd
minim
u
m
tem
p
er
ature
and
t
h
e
t
h
ir
d
sce
n
ari
o
(
sc
en
ar
i
o
3
)
is
f
or
t
he
i
npu
t
data
o
f m
a
xim
u
m
tem
p
era
t
ur
e a
nd di
ffe
re
nc
e be
tw
een
m
a
x
imum
a
nd
mi
nimu
m
t
e
m
p
er
a
t
u
r
e.
F
i
gure
6
s
h
ow
s
the
m
eas
ure
d
a
n
d
e
s
tim
ate
d
s
o
l
ar
e
ner
g
y
d
e
ns
i
t
y
for
three
scenar
ios.
T
he
v
alues
of
minim
u
m,
m
axi
m
um
a
n
d
a
v
e
r
a
ge
e
stim
ate
d
s
o
l
ar
e
nerg
y
den
s
i
t
y
on
t
h
e
fi
r
s
t
sce
n
ari
o
a
r
e
2
.28
1
8
.
09
MJ
/m
2
,
26.6
7
M
J
/
m
2
a
nd
1
7.8
8
M
J/
m
2
,
re
sp
e
c
t
i
ve
l
y
a
s
s
h
ow
n
i
n
T
ab
le
1
.
It
h
as
a
l
s
o
the
p
e
rc
e
n
ta
ge
error,
e
o
f
2
.
72
%, it in
d
i
c
a
te
s tha
t
t
he
r
esu
l
t
of e
s
tim
ate
d
sola
r
e
nerg
y d
e
ns
i
t
y
t
hou
ght
o
ut
o
f th
e
y
e
a
r
2
01
8
i
s
a
c
c
e
pt
able
. Th
e
val
u
es
o
f
m
i
n
i
m
u
m,
m
a
x
i
m
u
m
a
nd
a
v
era
g
e
est
i
ma
t
e
d
so
la
r
ener
g
y
d
e
n
s
i
t
y
o
n
t
h
e
s
e
c
o
n
d
s
c
e
n
a
r
i
o
a
r
e
h
i
g
h
e
r
tha
n
t
he
f
irs
t
s
ce
nari
o,
t
he
y
a
r
e
3.13
MJ/m
2
,
26.85
MJ/m
2
a
nd
1
7
.96
MJ/m
2
,
r
e
s
p
e
c
t
i
v
e
l
y
a
s
a
l
s
o
s
h
o
w
n
i
n
Tab
l
e
1.
T
he
r
e
s
ult
of
d
a
i
ly
e
st
ima
t
e
d
s
o
l
ar
e
nerg
y
de
nsi
t
y
is
a
l
s
o
a
c
cep
ta
ble
fo
l
l
ow
ing
i
t
s
per
cen
ta
ge
e
rror
,
e
of
2
.7
1%
.
Th
e
t
h
ird
sce
n
a
r
io
h
as
t
he
h
i
g
he
st
m
i
n
i
m
um
e
stim
ate
d
s
o
l
a
r
e
n
ergy
d
e
n
si
ty
o
f
3.95
MJ
/
m
2
c
o
mp
a
r
ed
t
o
t
h
e
fi
rst
an
d
th
e
sec
ond
s
cena
r
i
o
.
But
,
t
h
e
m
ax
i
m
u
m
e
st
i
m
a
t
ed
s
o
l
a
r
e
n
e
rgy
de
nsi
t
y
o
f
2
4.3
9
MJ/m
2
on
t
h
e
third
sce
n
a
r
i
o
i
s
t
h
e
l
o
w
e
st
v
alue
c
ompa
red
t
o
t
he
f
irs
t
an
d
t
h
e
sec
o
nd
s
c
enar
io.
The
a
v
era
g
e
est
i
ma
t
e
d
s
o
la
r
ene
r
gy
dens
ity
o
f
1
7
.95
MJ/m
2
on
t
h
e
th
ird
sce
n
ari
o
i
s
alm
o
st
s
am
e
with
t
he
f
irst
a
nd
t
h
e
seco
nd
scena
r
i
o
.
The
perc
en
t
a
ge
e
r
r
or,
e
o
f
2.7
69%
o
n
t
h
e
t
h
ir
d
sc
e
n
ari
o
a
s
sh
ow
n
i
n
T
a
b
le
1
i
s
a
l
s
o
s
t
i
ll
ac
cept
a
b
l
e.
T
h
e
a
c
cep
tat
i
on
o
f
e
stim
ate
d
s
ol
ar
e
ne
rgy
den
s
i
t
y
f
or
t
he
f
irs
t
,
sec
o
n
d
a
n
d
t
h
i
rd
s
ce
na
ri
o
is
b
ase
d
on t
h
e
requ
ire
d
ra
nge va
l
ue
of
-10%
t
o
+1
0%
a
s
sta
t
e
d
b
y [2
1].
The
a
v
era
g
e
e
s
t
i
m
a
ted
s
o
lar
ener
gy
de
ns
i
t
y
va
lue
s
o
f
1
7
.8
8
M
J
/m
2
,
17.
9
6
M
J/m
2
a
nd
1
7
.
95
MJ
/
m
2
for
the
first,
s
e
c
on
d
a
n
d
thir
d
sc
ena
r
io
a
re
e
qu
i
v
ale
n
t
t
o
4
.
9
7
k
W
h
/
m
2
,
4.
99
k
W
h/m
2
a
nd
4.
98
k
W
h
/
m
2
,
respe
c
t
i
ve
l
y
.
T
h
e
val
u
e
s
a
re
s
t
i
l
l
a
b
ove
4
.
0
0
kWh
/
m
2
,
t
h
e
y
a
r
e
s
t
i
l
l
c
l
a
s
s
i
f
i
e
d
i
n
t
h
e
v
e
r
y
h
i
g
h
s
o
l
a
r
e
n
e
r
g
y
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
So
l
a
r ene
r
gy
d
e
n
s
ity
est
i
m
a
t
i
on us
i
n
g ANFI
S bas
ed
o
n
d
a
i
l
y
m
a
x
i
m
u
m
an
d m
i
n
i
m
u
m
…
(
M
. Irwa
nt
o)
2
211
den
s
i
t
y.
T
he
y
a
l
s
o
c
a
n
b
e
ac
ce
pte
d
a
s
one
i
n
f
orm
a
tion
o
f
s
ol
a
r
e
n
er
gy
de
ns
i
t
y
est
i
ma
t
i
o
n
t
ha
t
gi
v
e
in
form
ation
t
h
at Me
d
a
n
has
g
o
o
d
p
o
t
e
n
t
i
a
l
for
PV
a
ppl
icat
i
on sy
st
em.
(a) S
cenario 1
(b)
S
cena
r
io 2
(c)
Scenario
3
F
i
gure
6. Me
a
s
u
red
an
d e
s
t
i
m
a
ted
s
o
la
r e
n
ergy
de
ns
ity
w
it
h
vari
ous i
n
p
u
t
d
ata
of A
N
F
IS
system
Tab
l
e 1.
The
M
in
i
m
um
, m
a
xi
m
u
m
, a
vera
ge
a
nd pe
rce
n
t
a
ge e
rror
of
estim
ate
d
so
l
a
r
e
ner
g
y
S
ce
n
a
rio
1
Sce
n
a
r
io
2
S
ce
n
a
rio
3
Mi
ni
m
u
m e
s
t
i
mated sola
r
e
n
e
r
gy
de
n
si
ty
(
MJ/m
2
)
2.
28
3
.
1
3
3.
95
Ma
xi
m
u
m
e
s
tim
at
e
d
s
ol
a
r
e
n
e
rgy
d
e
nsity
(
M
J
/
m
2
)
26.
67
26.
85
24.
39
Ave
r
a
g
e
e
s
ti
m
a
t
e
d
sola
r e
n
e
r
gy d
e
nsity
(MJ/
m
2
)
17.
88
17.
96
17.
95
P
e
r
cen
t
a
g
e
e
r
r
o
r
,
e
(
%)
2
.7
2
2
.
7
1
2
.6
9
4.
CONCL
U
S
ION
A
n
e
stim
at
i
on
of
s
o
l
ar
e
ner
g
y
de
nsi
t
y
i
n
Me
dan,
I
n
d
o
n
es
ia
h
a
s
b
e
e
n
c
ond
uc
t
e
d
a
n
d
a
n
al
yse
d
u
s
i
n
g
A
N
F
I
S
s
y
s
t
e
m
.
T
h
e
i
n
p
u
t
a
n
d
t
a
r
g
e
t
d
a
t
a
o
f
A
N
F
I
S
s
y
s
t
e
m
a
r
e
t
a
k
en
f
rom
Me
dan
m
e
teor
ol
o
g
ica
l
s
ta
t
i
o
n
thr
o
u
g
h
t
he
w
e
b
s
it
e
o
f
w
or
ld
w
ea
t
h
e
r
o
n
l
i
n
e
for
the
tem
p
er
a
t
ur
e
a
nd
so
lar
e
n
erg
y
d
e
n
s
i
ty.
S
o
me
c
onc
l
u
s
i
o
n
s
of
t
h
i
s pa
per
can
b
e
sta
t
e
d
be
l
ow
.
The
a
v
e
r
age
me
asured
s
o
l
ar
e
ner
g
y
dens
i
t
y
i
n
M
e
d
a
n
i
s
5.
0
3
k
Wh
/
m
2
.
I
t
i
s
a
v
a
l
u
e
o
f
s
o
l
a
r
e
n
e
r
g
y
den
s
i
t
y
ab
ove
4
.
00
kWh
/
m
2
a
nd
i
t
i
s
c
l
a
ssi
fie
d
i
n
the
ver
y
h
igh
so
la
r
ene
r
g
y
d
e
n
si
t
y
a
nd
it
a
l
so
g
i
v
es
g
o
o
d
po
te
nt
i
a
l
for
P
V
a
ppl
icat
i
o
n sys
t
e
m
.
Thr
ee
sce
n
ar
io
s
of
i
n
p
u
t
d
a
t
a
of
A
N
F
IS
s
yst
e
m
(
m
inimu
m
a
nd
ma
x
i
m
u
m
te
mpe
r
at
ure
,
m
inim
um
tem
p
era
t
ur
e
an
d
d
i
ffe
r
enc
e
b
etwe
en
m
ax
imum
a
nd
m
i
n
i
m
u
m
tem
p
er
at
ure,
a
nd
t
h
e
m
a
xim
u
m
tem
p
er
a
t
ure
and
differ
e
n
ce
b
e
t
w
e
en
m
a
x
i
m
um
a
nd
m
inim
um
t
em
per
a
t
u
r
e
)
resul
t
th
e
a
v
era
g
e
esti
ma
t
e
d
sol
a
r
en
e
r
gy
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
: 208
8-
869
4
I
nt
J
P
ow
Elec
& Dr
i
S
y
st V
ol.
10,
N
o.
4
, Dec
201
9 : 2
2
0
6
–
22
13
2
212
den
s
i
t
y
are
4.9
7
k
Wh
/m
2
,
4
.
99
kWh
/
m
2
a
nd
4
.
98
k
W
h
/
m
2
,
re
sp
e
c
t
i
v
e
l
y
.
Th
ey
a
re
a
l
s
o
cl
assi
fi
e
d
i
n
t
h
e
v
e
ry
hi
gh
so
l
a
r e
n
ergy
de
ns
i
t
y.
Base
d
o
n
t
he
a
na
lys
i
s
o
f
p
erc
e
nta
g
e
e
rror
show
s
t
h
a
t
t
he
e
stim
a
te
d
so
lar
ene
r
gy
den
s
i
ties
ar
e
ac
cept
a
b
l
e
bec
a
use
the
i
r
va
lu
es
a
re in the
re
quir
e
d r
a
nge
o
f -
1
0
%
to +10%.
5.
ACKNOW
LEDG
E
MEN
T
S
Th
is
w
or
k
w
a
s
sup
p
o
rte
d
i
n
part
by
th
e
Indo
ne
sian
M
in
is
try
o
f
E
d
u
cat
i
on,
R
e
s
e
a
rc
h
an
d
Tec
h
nol
og
ica
l
u
n
d
er
W
orl
d
C
lass Resea
r
c
h
G
rant
f
or
p
erio
d 20
1
9
-
20
20
.
REFE
RENCES
[1]
I.
D
aut,
e
t
al.,
"
P
o
t
e
ntial
of
S
olar
R
adi
a
t
i
o
n
a
nd
W
in
d
S
p
eed
f
or
P
h
o
to
volt
a
ic
a
nd
W
ind
Po
wer
Hy
bri
d
G
enerat
ion
in
P
erlis,
Northern
M
al
a
y
si
a,"
T
h
e
5
t
h
In
ter
nat
io
nal Po
wer Eng
i
n
eeri
n
g
a
nd O
p
timizati
on Confer
ence
(P
EOCO20
11
)
,
S
h
ah
Ala
m,
S
e
l
a
n
go
r,
M
a
l
ay
sia:
p
p. 6-7
J
u
n
2
01
1
.
[2]
M.
Irw
ant
o
,
et
a
l
.
,
"E
ff
ect
o
f
So
l
a
r
Irradi
ance
and
Tem
p
erature
o
n
P
h
ot
ovolt
a
ic
M
o
d
ule
El
ectri
ca
l
Ch
aracteris
ti
cs,
"
Pr
oceedi
n
g
s
o
f
t
h
e In
tern
atio
nal Po
s
t
gr
ad
ua
t
e
Con
f
er
ence on
En
gi
neeri
n
g
(
I
PCE
201
0)
16
-1
7
Oc
to
be
r 20
10
,
Perlis,
Mal
a
ysia.
[3]
S
.
H
.
Cho
ng,
e
t
al
.,
"
O
ut
pu
t
en
er
gy
m
ax
imizat
io
n
of
a
s
ing
l
e
ax
i
s
p
h
o
to
vo
lt
aic
so
lar
tracki
n
g
s
y
st
em
:
exp
e
rim
e
n
t
al
veri
ficati
on,
"
Inter
n
a
t
i
onal Jo
urna
l o
f
Po
wer
E
l
ectr
o
n
i
cs
and
Dr
ive Sys
t
em
(
I
JPED
S
)
,
vo
l.
1
0(3
)
,
pp
.
16
55
-16
6
1
,
20
19
.
[4]
A.
A
.
Ab
dulrazzaq
a
n
d
A
.
H
.
A
li
,
"Effici
ency
P
erf
o
rm
ances
o
f
Tw
o
M
P
P
T
A
lgor
it
h
m
s
f
o
r
PV
S
ys
t
e
m
W
i
th
Diff
ere
n
ceSol
ar
P
anels
Irradiances
,
"
In
ter
nat
io
nal Jou
r
n
a
l
o
f
Power E
l
ectr
onics a
n
d
D
r
i
ve
S
y
st
em
(
I
JPE
D
S
)
,
v
o
l
.
9(4
)
,
p
p
.
1
75
5-1764
,
2
01
8.
[5]
R
.
A
.
M
e
j
e
e
d
.
,
"
D
e
s
i
g
n
o
f
S
o
l
a
r
P
h
o
t
o
v
o
l
t
a
i
c
P
r
e
s
s
u
r
i
z
e
d
D
r
i
p
I
rr
igat
i
on
Pu
m
p
ing
Syst
e
m
a
t
Al-s
alm
a
n
D
i
s
t
ric
t
i
n
S
a
m
a
wa
G
ov
erno
rat
e
,
"
In
tern
at
io
na
l Jour
na
l o
f
P
o
wer El
ectr
o
ni
cs an
d Drive Syst
em
(
I
J
P
ED
S
)
,
vol.
10
(3),
pp.
16
28
-163
7,
2
0
1
9
.
[6]
I. Du
t
, et
al.
,
"
Hi
gh
Power
T
ra
n
s
fo
rm
erless
P
hotovo
lt
a
i
c
In
vert
er,"
E
n
er
gy P
r
oced
ia
, vo
l
. 3
6,
pp
.
4
6
5
-4
72
,
2
0
1
3
.
[7]
M
.
I
rw
ant
o
,
et
a
l.
,
"Aff
ect
o
f
M
a
xi
m
u
m
Vo
ltag
e
A
n
g
l
e
on
T
h
r
ee-L
ev
el
S
i
ngle
P
h
as
e
Tran
sf
o
r
merl
ess
P
h
o
t
ovo
lt
aic
Inv
e
rter P
erf
o
rman
ce,
"
Inter
n
a
t
i
o
n
a
l
Jour
nal of Eng
i
n
eeri
ng
and
A
pplied
Sci
e
nces
,
vol.
5
,
pp
.
20
-2
9
,
2
014
.
[8]
[8]
M
.
M
asri,
et
a
l
.
,
"
E
ff
ect
o
f
M
a
x
i
m
u
m
Volt
age
Ang
l
e
on
I
n
v
er
ter
P
e
rf
orm
a
nce
Ap
p
l
i
e
d
in
U
n
i
n
t
erru
pt
ed
P
o
w
er
Su
pp
ly
(UP
S),
"
A
p
p
l
i
e
d M
echan
ics
an
d
M
a
t
e
ri
a
l
s
,
v
o
l
.
7
93,
pp.
304
-308
,
2
01
5.
[9]
M
.
Irwant
o
,
et
a
l
.,
"
A
nal
y
sis
of
A
C
V
o
ltag
e
a
n
d
C
urrent
W
avef
o
r
m
D
i
stortio
n
on
SPW
M
T
r
ans
f
orm
e
rless
Ph
oto
v
l
ta
ic
Inv
e
r
te
r,"
Far Eas
t
J
o
urnal of Elect
ro
nic
s
a
n
d
Comm
un
ic
a
tio
ns
,
vol.
17
(5),
p
p.
116
7-1
1
7
6
,
2
01
7.
[10]
H.
A
la
m
,
e
t
al
.,
"
An
alys
is
o
f
AC
V
o
l
t
a
ge
W
av
ef
orm
o
n
C
han
g
eo
ver
o
f
Trans
f
er
S
witch
on
Ph
ot
ov
lt
aic
P
o
w
e
red
Uninterrupti
b
l
e
P
ow
e
r
S
upp
ly
Sys
tem,
"
Fa
r Eas
t
J
o
urn
a
l
o
f
Ele
c
tron
ic
s an
d Co
mmun
ic
at
io
ns
,
vol.
1
7
(5
),
pp
.
1
02
9
-
10
35
,
2
0
1
7
.
[11]
H.
A
l
a
m
,
e
t
al.
,
"
Ou
tp
ut
C
harac
t
eristics
o
f
P
ho
to
vo
lta
i
c
M
o
dul
e
i
n
Me
dan
Based
on
E
st
im
ated
S
ol
ar
Irradi
ance
Us
ing
Hargreaves
M
ethod
f
o
r
Appl
i
cation
Asses
s
m
e
nt
o
f
Trans
f
or
m
e
r
le
ss
P
ho
to
vo
lta
i
c
In
ve
rte
r
,"
AIP
Co
nf
e
r
ence
Pr
oceedi
n
g
s
,
vol.
1
77
,
2
016
.
[12]
M
.
M
asri
.
e
t
a
l
.,"Op
timu
m
S
iz
i
n
g
o
f
P
hotov
o
l
ta
ic
P
ow
ered
U
ni
nt
e
rrup
t
ib
le
P
owe
r
S
up
ply
,
"
Far
E
a
st
Jo
ur
nal
of
Ele
c
t
ron
i
c
s
an
d
Co
mmun
ic
a
t
io
n
s
,
vol.
1
7
(5
),
p
p
. 1
11
1-1
117
,
2
017.
[13]
M
.
M
as
ri.
et
a
l.,"
S
o
lar
Rad
i
at
io
n
Po
tenti
a
l
a
s
E
nerg
y
So
urce
of
P
hot
ov
oltaic
P
owered
U
ni
nt
errupted
P
ow
er
S
up
ply
in
P
erl
i
s,
N
or
t
h
e
r
n
Malaysia,"
IO
SR
Jou
r
na
l o
f
Elect
r
i
cal
an
d Electr
onics
En
gineeri
n
g
(
I
OSR-JEE
E
)
,
vol
.
6,
p
p.
3
1
-3
6, 2
01
6.
[14]
O.
L
.
La
pe
ñ
a
a
nd
R
.
P.
A
re
ny
,
"
S
ola
r
E
n
e
rgy
R
a
dia
tion
Me
a
s
u
r
e
m
e
nt
w
ith
a
Low–P
o
wer
Solar
En
erg
y
H
arv
e
s
t
er,"
Com
put
ers an
d Elect
ro
n
i
cs i
n
Agr
i
cultu
re
,
vol.
151
,
p
p.
1
50
–1
55
,
20
15
.
[15]
A.
N
.
Sy
afwat
i
.
et
a
l
.,"P
o
ten
t
i
a
l
of
S
o
l
ar
E
nerg
y
Harv
esti
ng
i
n
U
lu
P
auh
,
P
erlis
,
M
alay
sia
u
s
in
g
S
o
l
a
r
Rad
i
atio
n
–
Analysis
S
tudi
es
,"
E
n
er
gy Proced
ia
,
v
o
l.
14,
p
p
.
150
3-1
5
0
8
,
2
012.
[16]
Y.M.
Irwan
.
et
a
l.,"P
o
tent
ia
l
of
S
o
l
ar
R
adiatio
n
and
A
m
bien
t
Te
m
p
era
t
ure
as
a
n
Altern
ativ
e
Energ
y
i
n
P
e
rlis,
"
Applied Mechani
c
s and
Materia
ls
,
vol.
793,
p
p
.
3
2
3
-32
7
,
20
15.
[17]
M.
Irwant
o
.,
"
S
olar
Irradi
a
n
ce
and
O
p
t
i
m
u
m
T
ilt
A
ngle
o
f
Ph
otovo
lt
a
i
c
Mo
d
u
le
i
n
Tanj
un
g
M
o
raw
a
,
N
o
rth
Sum
a
tera,
Indonesi
a,"
Int
e
rn
a
t
ional
Jo
ur
nal o
f
Re
s
e
ar
ch in
A
d
van
ced En
gin
eeri
n
g
a
nd T
echn
o
l
o
g
y
,
v
o
l
.
1
,
p
p
.
3
4
-
38
,
2
015
.
[18]
A.
G
eorge.
e
t
al,
"Revi
e
w
o
f
S
o
l
ar
E
n
e
rg
y
D
e
velo
pm
en
t
in
K
eny
a
:
O
p
p
o
r
t
u
n
i
t
i
e
s
a
n
d
C
h
a
l
a
n
g
e
s
,
"
Re
n
e
w
a
bl
e
Energy Focus
,
v
o
l.
29,
p
p
.
1
23
-140
,
2
01
9.
[19]
H.
P
.
Das
a
r
i
.
e
t
a
l
,
"
H
i
gh-resoluti
on
Ass
ess
m
ent
of
S
ol
ar
E
nerg
y
Reso
urces
O
v
e
r
the
Arab
ian
P
e
nin
s
ula,"
Appli
e
d
Energy
,
v
o
l
.
2
4
8
, pp
. 3
54
-3
71
, 2
01
9.
[20]
Y.
F
.
N
a
ss
ar.
et
a
l
,
"
As
sessm
ent
of
S
ol
ar
E
nergy
Potential
i
n
G
aza
S
t
rip-P
a
l
e
stine,
"
Su
stain
a
b
l
e E
n
er
g
y
Te
c
h
no
log
i
e
s
an
d Asse
ss
me
nts
,
vol
.
31
,
p
p
.
318
-3
2
8
,
201
9.
[21]
I.
D
aut
.
e
t
al.,
"Com
bi
na
t
i
o
n
o
f
H
a
rgreaves
M
et
h
o
d
and
L
i
near
R
egress
io
n
a
s
a
N
ew
M
etho
d
to
E
stim
ate
S
o
lar
Radi
ation
in
P
er
lis,"
Northern Malaysia,
So
l
a
r
E
n
e
r
gy
,
v
o
l
. 85
,
p
p. 2
87
1-2
8
8
0
, 2
01
1.
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
So
l
a
r ene
r
gy
d
e
n
s
ity
est
i
m
a
t
i
on us
i
n
g ANFI
S bas
ed
o
n
d
a
i
l
y
m
a
x
i
m
u
m
an
d m
i
n
i
m
u
m
…
(
M
. Irwa
nt
o)
2
213
[22]
K.
S
aleh.
et
a
l.,
"
E
stim
at
i
o
n
of
S
olar
Irradi
ation
in
M
edan
U
s
i
ng
H
a
r
gre
a
v
e
s
M
e
t
ho
d
Ba
se
d
o
n
Min
i
mu
m
a
nd
M
a
xi
mum
T
e
m
p
eratu
r
e
f
o
r
P
o
ten
t
i
a
l
Ass
essm
e
n
t
of
P
hot
ov
o
ltaic
P
o
wer
Generation,"
A
d
va
nced Sci
e
nce
L
e
t
t
er
s
,
vo
l.
23(5
)
,
p
p
.
4
4
63-4
4
6
6
,
2
01
7.
[23]
J
.
J
u
n
g
.
e
t
a
l
.
,
"
D
ig
it
a
l
N
u
m
e
r
ic
a
l
M
a
p
-
O
r
i
e
n
te
d
E
s
t
i
m
a
t
i
o
n
o
f
S
ola
r
E
ne
rg
y
P
o
te
nt
ia
l
f
o
r
S
ite
S
election
o
f
P
h
o
t
ov
o
l
ta
i
c
S
o
l
ar P
anel
s o
n
N
ati
onal
H
i
ghway
Slo
pes
,
"
Appli
e
d E
n
er
gy
, vo
l
.
24
2
, p
p.
57
–
6
8
,
2
0
1
9
.
[24]
Z.
H
.
A
l
i
.
e
t
al.,"M
odel
i
n
g
S
ol
ar
M
o
d
u
l
es
P
erf
o
rm
an
ce
U
n
d
e
r
T
e
m
p
e
ratu
re
a
n
d
S
ol
ar
R
ad
iati
on
o
f
W
e
st
ern
Iraq,
"
Int
e
rna
t
i
o
n
a
l
Jo
u
r
n
a
l of Po
wer
E
l
ectr
onics an
d
D
r
i
ve System (
I
JPED
S
)
,
vol.
9
(4),
pp.
1
8
4
2
-
185
0,
2
0
1
8
.
[25]
M
.
R
ijwan.
et
a
l
.
,"F
u
zzy
L
og
ic
B
ased
M
o
d
eli
ng
an
d
Es
tim
a
ti
on
o
f
G
lo
bal
S
o
lar
Energ
y
Usin
g
M
eteo
rolo
g
i
cal
Parame
t
e
rs," E
n
e
rgy
, vo
l
. 70
, pp
. 6
85
-69
1
,
2
01
4
.
[26]
E.
A
d
ı
gü
ze
l
.
e
t
a
l
.,
"P
redi
cti
on
o
f
d
u
s
t
p
a
rti
c
le
s
ize
effect
o
n
e
ffi
c
ien
c
y
of
p
hotov
ol
ta
i
c
m
o
d
u
l
e
s
w
it
h
ANF
IS:
A
n
exp
e
rim
e
nt
al s
tudy
i
n
Aeg
ean
r
eg
io
n,
T
urk
e
y,
"
Sola
r
Ener
gy
,
vol.
1
77
,
p
p
.
6
9
0
-
7
0
2,
2
01
9.
[27]
T.
T
ak
agi
and
M
.
S
u
g
eno
,
"
F
u
z
z
y
i
d
ent
i
fi
cation
o
f
s
yst
e
m
s
a
nd
it
s
ap
plicati
ons
t
o
m
odelin
g
an
d
cont
rol
,
"
IE
EE
Tran
s.
S
y
st.
,
Ma
n
,
Cy
be
rne
t
.
S
M
C-15
,
p
p
. 1
16
–1
32
, 19
8
5
.
[2
8]
R.
L
a
l
eman
.
et
a
l.,
"
L
if
e
Cycl
e
A
n
al
ysi
s
t
o
Estim
ate
The
E
n
v
i
ro
n
m
ent
Im
p
act
o
f
Resed
e
n
tial
P
h
ot
ovltai
c
S
ys
t
e
ms
in Reg
i
o
n
w
ith
L
ow So
l
ar Radiat
i
o
n
,"
Ren
e
wabl
e an
d
Susta
in
able E
n
erg
y
Revi
ew
,
v
o
l
. 1
5,
pp
.
26
7
-
2
81
, 20
1
1
.
B
I
OGRAPHIES
O
F AUTHO
RS
M
.
I
rw
ant
o
r
eceiv
e
d
hi
s
P
h
D
d
e
gr
ee
in
E
lectri
cal
S
ys
te
m
Engin
e
e
ring
f
ro
m
Uni
v
e
r
s
i
t
i
M
a
l
aysia
P
e
rlis
(
U
n
iMA
P
),
M
alay
si
a
in
2
01
2.
H
e
i
s
c
u
rrent
ly
a
l
ect
urer
i
n
Depart
m
e
nt
o
f
E
l
ect
rical
Engineering
,
I
ns
t
i
tut
T
e
kno
l
ogi
Me
d
a
n
(
I
T
M)
.
H
e
i
s
a
l
so
f
e
l
lo
w
o
f
C
ent
r
e
o
f
E
x
c
el
ence
f
o
r
Renewab
l
e
Energ
y
(
CE
RE),
S
ch
o
o
l
o
f
E
lect
rical
S
ys
te
m
E
ngin
eeri
n
g,
U
n
i
v
e
r
s
i
t
i
M
a
la
ys
ia
P
e
r
l
i
s
(Un
i
MAP
)
.
His
research
i
n
t
erest
i
n
cl
ud
e
s
p
ow
er
e
lect
ron
i
c,
e
lec
tri
cal
p
o
w
er
s
ys
te
m
s
t
ab
ilit
y
a
nd
so
lar
en
erg
y
a
nd
pho
to
volt
a
ic
a
p
p
li
cati
o
n
sy
st
em.
H.
A
l
a
m
receiv
e
d
hi
s
P
h
D
degree
in
E
lectri
cal
S
yst
e
m
E
ngineeri
n
g
f
r
o
m
U
niver
s
iti
Malaysi
a
P
e
rlis
(
U
n
iM
A
P
),
M
alay
sia
in
2
0
1
9
.
H
e
is
c
urrent
ly
a
l
ect
urer
i
n
D
e
partm
e
n
t
o
f
Com
p
u
t
er
Engineering
,
I
nstitu
t
T
e
kno
l
ogi
Medan
(IT
M)
.
His
research
i
nter
est
i
n
cl
ude
s
a
rti
f
icial
intellegent
syste
m
, so
l
a
r
e
ne
rg
y
a
n
d p
h
o
t
ov
olta
ic
a
pp
lic
a
t
io
n sys
t
e
m
.
M
.
M
as
ri
r
eceiv
e
d
his
Ph
D
deg
r
ee
i
n
C
om
p
u
ter
En
gi
neerin
g
f
r
om
U
niver
s
iti
Malaysi
a
P
erlis
(Un
i
MAP
)
,
M
a
l
ays
i
a i
n
201
6.
He i
s
c
urrent
ly
a lect
urer i
n D
e
par
t
m
ent
of
C
o
m
puter
Engi
neering,
Ins
t
i
t
u
t
T
ekno
logi
M
edan
(ITM
)
.
Hi
s
res
earch
i
nt
erest
in
clud
es
a
r
ti
fic
i
a
l
i
n
t
e
lle
ge
n
t
s
yste
m
,
s
ol
a
r
energ
y
an
d
p
ho
tov
o
l
t
a
i
c app
l
icat
io
n s
y
stem
.
B.
I
sm
a
i
l
received
h
i
s
P
h
D
deg
r
ee
in
E
l
ectri
cal
S
y
s
t
e
m
En
g
i
n
eer
ing
f
r
om
U
nive
rsiti
Malaysia
P
e
rlis
(
U
n
iMA
P
),
M
al
aysi
a
i
n
201
5.
H
e
is
c
urre
nt
ly
a
l
ectu
r
er
i
n
S
c
ho
ol
o
f
El
ectrical
S
y
s
te
m
Engineering
,
U
niversit
i
Mal
a
ys
i
a
P
e
r
l
i
s
(
U
n
i
M
A
P
)
.
H
e
i
s
a
l
s
o
C
h
ei
f
of
C
en
tre
o
f
E
x
celen
c
e
f
or
Renewab
l
e
Energ
y
(
CE
RE),
S
ch
o
o
l
o
f
E
lect
rical
S
ys
te
m
E
ngin
eeri
n
g,
U
n
i
v
e
r
s
i
t
i
M
a
la
ys
ia
P
e
r
l
i
s
(Un
i
MAP
)
.
H
i
s res
e
a
r
ch
in
t
eres
t incl
ud
e
s
p
ower electro
ni
c
and
r
enewab
le en
e
rgy
sy
st
e
m
.
W.
Z
.
Leo
w
r
ecei
ved
hi
s
P
h
D
deg
r
ee
i
n
E
lect
rical
S
y
s
te
m
E
ngin
e
e
r
i
ng
f
rom
Universi
ti
M
a
l
aysia
P
e
rlis
(
U
n
iMA
P
),
M
al
aysi
a
i
n
201
8.
H
e
is
c
urre
nt
ly
a
l
ectu
r
er
i
n
S
c
ho
ol
o
f
El
ectrical
S
y
s
te
m
Engineering
,
U
ni
versit
i
Malaysia
P
e
r
lis
(
U
n
i
MA
P)
.
He
i
s
a
l
so
m
e
m
b
er
o
f
Cent
re
o
f
Ex
celen
c
e
f
o
r
Ren
e
wab
l
e
E
n
ergy
(
CE
RE
),
S
ch
oo
l
o
f
E
lectri
cal
S
y
s
t
e
m
Engi
ne
eri
ng,
U
niversi
t
i
M
a
laysia
P
e
rlis (UniMA
P
). H
i
s
r
esearch int
erest
in
clud
es
cool
in
g s
y
stem
an
d ren
e
wabl
e energ
y
s
ys
te
m
.
Y.
M
.
Irw
an
h
as
h
i
s
B
.
Elect.
E
ng.
(
H
o
n
s
),
M
S
c
a
nd
P
h
D
d
egre
e
in
E
l
ectrical
S
y
s
tem
En
gin
eerin
g
f
r
om
U
n
i
v
e
rsi
t
y
Mal
a
ysi
a
P
e
r
l
i
s
in
2
00
7,
2
010
a
nd
2
01
5,
r
esp
ecti
v
ely
.
I
n
2
010
,
he
jo
in
e
d
t
he
D
epart
m
ent
o
f
E
lect
rical
S
ystem
E
n
gi
neeri
n
g
at
U
n
i
ve
rs
it
y
M
a
l
a
ysia
P
erl
i
s
as
a
lect
urer.
Hi
s
areas
o
f
i
n
t
e
re
s
t
i
nclu
de
p
ower
q
ual
i
t
y,
a
dj
ustab
l
e
-sp
eed
d
ri
ves
,
e
n
e
rgy
co
nv
ersi
on
and
p
o
wer
sy
s
t
em
a
pp
li
cati
ons.
He
h
as
a
ut
ho
red
and
coau
th
ored
m
ore
th
an
1
0
0
t
echn
i
cal
p
apers
in
th
e
natio
nal, in
t
ern
a
ti
onal j
ourn
a
l an
d co
nf
erences
.
Evaluation Warning : The document was created with Spire.PDF for Python.