Yang, Benshuo; Xu, Haojun
A icle
Resol ing he con lic o nuclea was ewa e discha ging
in o he ocean based on he GMCR
Ma ine Economics and Managemen (MAEM)
P o ided in Coope a ion wi h:
Ocean Uni e si y o China, Qingdao
Sugges ed Ci a ion: Yang, Benshuo; Xu, Haojun (2022) : Resol ing he con lic o nuclea was ewa e
discha ging in o he ocean based on he GMCR, Ma ine Economics and Managemen (MAEM), ISSN
2516-158X, Eme ald, Leeds, Vol. 5, Iss. 1, pp. 45-55,
h ps://doi.o g/10.1108/MAEM-08-2021-0007
This Ve sion is a ailable a :
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Resol ing he con lic o nuclea
was ewa e discha ging in o he
ocean based on he GMCR
Benshuo Yang and Haojun Xu
Ocean Uni e si y o China–Laoshan Campus, Qingdao, China
Abs ac
Pu pose –Japan’s decision o elease nuclea was ewa e in o he Paci ic Ocean in 2023 has spa ked s ong
opposi ion a home and ab oad. In his s udy, G aph Model o Con lic Resolu ion (GMCR) me hod is adop ed
o analyze he con lic p oblem, and easonable equilib ium solu ions a e gi en o sol e he con lic e en .
Design/me hodology/app oach –In his s udy, GMCR is adop ed o sol e he con lic p oblem. Fi s ,
iden i y he key decision-make s (DMs) on he issue o nuclea e luen and he ele an op ions hey migh
adop . Second, he op ions o each DM a e a anged and combined o o m a se o easible s a es. Thi dly, he
g aph model is cons uc ed acco ding o he change o DM’s op ions, and he ela i e p e e ence o each DM is
de e mined. Finally, he con lic p oblem is sol ed acco ding o he de ini ion o GMCR equilib ium.
Findings –Discha ging nuclea was ewa e in o he ocean is no he igh choice o sol e he p oblem.
De eloping mo e space o s o e nuclea was ewa e is mo e conduci e o he p o ec ion o he ocean
en i onmen .
P ac ical implica ions –I is undesi able o he Japanese go e nmen o unila e ally discha ge nuclea
was ewa e in o he ocean. Objec i ely assessing he adioac i i y o nuclea was ewa e and he coope a ion o
ele an s akeholde s can be e sol e his con lic .
O iginali y/ alue –The p oblem a ising om Japan’s eleasing plan is complica ed because o a lack o
in o ma ion and he exis ence o mul iple s akeholde s, while GMCR can help us wi h a be e iew o he
cu en ci cums ance in he con lic .
Keywo ds Ocean managemen , Ocean en i onmen , Nuclea was ewa e , GMCR
Pape ype Resea ch pape
1. In oduc ion
On 13 Ap il 2021, Japan announced i would elease 1.25 million ons o ea ed nuclea
was ewa e in o he Paci ic Ocean in wo yea s. The decision has been s ongly ques ioned
and opposed by esiden s and neighbo ing cos al coun ies including China, Russia, Sou h
Ko ea and No h Ko ea (Nog ady, 2021).
The adioac i e was ewa e esul s om a disas ous nuclea mel down acciden in
Fukushima Daiichi Nuclea Powe Plan (FDNPP), which is in he cha ge o Tokyo Elec ic
Powe Company (TEPCO). On 11 Ma ch 2011, he G ea Sendai Ea hquake and a ollowing
Con lic o
nuclea
was ewa e
discha ging
45
© Benshuo Yang and Haojun Xu. Published in Ma ine Economics and Managemen . Published by
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The cu en issue and ull ex a chi e o his jou nal is a ailable on Eme ald Insigh a :
h ps://www.eme ald.com/insigh /2516-158X.h m
Recei ed 18 Augus 2021
Re ised 17 Sep embe 2021
Accep ed 13 Oc obe 2021
Ma ine Economics and
Managemen
Vol. 5 No. 1, 2022
pp. 45-55
Eme ald Publishing Limi ed
2516-158X
DOI 10.1108/MAEM-08-2021-0007
gian sunami hi FDNPP, leading o hyd ogen explosions and se e e adioac i e
con amina ion elease. In he ime since he acciden , he wa e o cooling nuclea
eac o s, as well as he ainwa e and g oundwa e seeping in o he eac o s, has gene a ed
la ge amoun s o nuclea was ewa e , which is anspo ed o la ge anks in he plan a ea o
s o age (TEPCO, 2021a). Howe e , i is expec ed ha all anks would be illed up a ound he
middle o 2022, and limi ed was e wa e s o age space ha e led Japan o decide o discha ge
con amina ed nuclea was ewa e in o he sea (TEPCO, 2021b).
Acco ding o TEPCO, was ewa e is ea ed in a mul i-nuclide emo al acili y (Ad anced
Liquid P ocessing Sys em), he eby emo ing mos o he 62 iso opes excep o i ium, which
means in addi ion o i ium, he e a e s ill o he adionuclides emaining in he ea ed
was ewa e , such as
14
C,
137
Cs,
134
Cs (TEPCO, 2021c). To educe he isk o discha ged
con amina ed wa e , Japan p oposed o g adually elease he ea ed wa e a e epu i ica ion
and dilu ing he i ium concen a ion o 1/70 o he adia ion sa e y s anda d o d inking
wa e o he Wo ld Heal h O ganiza ion. Al hough Japan’s decision seems o be in line wi h he
in e na ional p ac ice o nuclea was ewa e discha ge, i is dis inc i e om he no mal
ope a ion o nuclea powe plan s o elease such la ge amoun s o adioac i e was ewa e o
he ocean, especially a e a se ious nuclea leakage in 2011 (Buessele , 2020).
The eleased adionuclides would sp ead apidly along wi h ocean cu en s, causing
widesp ead impac . I is epo ed ha he a i icial adioac i e iso opes om FDNPP ha e
a i ed wes e n ma gin o he Paci ic Ocean and wes coas o No h Ame ica wi hin 2 yea s
a e he Fukushima Nuclea Acciden (Smi h e al., 2015;Suseno and Wahono, 2018).
Though sea cu en s would help dilu e nuclea pollu an s in he wa e nea Japan, iso opes
con ained in anks wi h high sea loo sedimen -wa e dis ibu ion coe icien and high
biological concen a ion ac o including
14
C,
137
Cs and
134
Cs do no dispe se wi h ocean
cu en s, bu easily accumula e on seabed and in ma ine o ganisms a ound Japan, posing a
las ing h ea o he local ma ine ecosys em (Lu e al., 2021). Ma ine li es and human a e
igh ly connec ed by he ood web, esul ing in a u he accumula ion in o ganisms along
ood chains, and he highe he ood chain le el, he g ea e he deg ee o biological
con amina ion by adioac i e subs ances (Buessele , 2012;Ala a and Gobas, 2016;Okamu a
e al., 2016).
Releasing adioac i e was ewa e o he ocean is no he only solu ion adop able, howe e .
Wi h a 12.3-yea hal -li e, 97% o he i ium con ained in anks will decay in 60 yea s, along
wi h hose iso opes o sho e hal -li e (Buessele , 2020). Though TEPCO claims a lack o
oom o accumula ing was ewa e , he e is s ill space o addi ional was ewa e on land
adjacen o FNDPP campus. The s o age would allow adionuclides o decay in anks, while
buying ime o de elopmen o new ea men echniques. The e a e also o he ways o deal
wi h he adioac i e was ewa e , such as unde g ound bu ial, con olled apo elease,
injec ion o geosphe e, e al. bu Japan has chosen he mos cos -e icien , bu mos ha m ul
one (Lu e al., 2021).
Conce ns o e con amina ed ish de as a ed he egional ishing indus y, and
uncon olled adionuclides eleased in o he ocean would cause long-las ing e ec o
esiden s and people in o he coun ies. Wi hou ully discussion and nego ia ion wi h
esiden s and neighbo ing coun ies, he unila e al decision by Japan has aised se e e
con lic s. Game heo y has been wisely applied in such ansbounda y con o e sies in
en i onmen al p o ec ion (Jø gensen and Zaccou , 2001;Pe osjan and Zaccou , 2003;Ni and
Wang, 2007;Jø gensen, 2010). Ca dinal p e e ences o decision-make s (DMs) a e he key
ac o s o he co ec ness and accu acy o a model in classic game heo y. Howe e , in he
issue o he Fukushima nuclea was ewa e discha ge con lic , much in o ma ion including
p e e ences o DMs is no su icien , leading o limi a ions in he applica ion o adi ional
game model. G aph Model o Con lic Resolu ion (GMCR) is a me hod be ween quali a i e
and quan i a i e analysis. I only needs limi ed in o ma ion such as quali a i e p e e ences o
MAEM
5,1
46
DMs o g asp a gene al and clea knowledge abou he essen ial o he con lic , he eby
helping o ecas esul s o he con lic o ace he causes o he esul .
This s udy has wo main con ibu ions. (1) In he exis ing esea ch on nuclea was ewa e
discha ge managemen , he e is li le analysis on he s a egies o each DM. This s udy ies
o lis he op ions o each DM and combine hem o o m he possible esul s o he con lic
e en . (2) This s udy a emp s o apply he GMCR model o he con lic o nuclea was ewa e
discha ge, he local equilib ium and global equilib ium o a e calcula ed, which p o ides a
e e ence o he esolu ion o con lic e en s.
The con en s o he emainde o he pape a e as ollows: Sec ion 2 is dedica ed o an
in oduc ion o he de elopmen o GMCR, while Sec ion 3 p esen s he basic s uc u e and
de ini ions o he g aph model. In Sec ion 4, a g aph model is s uc u ed acco ding o he
con lic o nuclea was ewa e discha ging in o he ocean om FNDPP and he equilib iums
wi h ega d o di e en solu ion concep s a e analyzed. Finally, Sec ion 5 p esen s he
concluding ema ks.
2. The de elopmen o GMCR
De eloped om no ma i e game heo y, GMCR is used o e eal how in e ac ions among
indi idual DMs o g oups lead o a inal con lic ou come (Kilgou e al., 1987;Fang e al.,
1993). The use o a di ec ed g aph, which p esen s DMs’in e ac ions consis ing mo es and
coun e -mo es and p e e ences o each DM wi h espec o possible scena ios, di e en ia es
GMCR om o he con lic models. The cu en de elopmen in GMCR is ocused on i e
aspec s: p e e ence in o ma ion, s abili y concep s, in e se analysis, coali ion GMCR and
applica ion.
As a cha ac e iza ion o alues o DMs, p e e ence in o ma ion is he key ing edien in a
con lic model and he ea ly GMCR only akes in o accoun simple p e e ences (Fang e al.,
2003a,b). The s eng h o p e e ence was concei ed and de eloped la e o deal wi h con lic s
whe e a DM p e e s one scena io g ea ly o e ano he (Hamouda e al., 2004,2006). In some
ci cums ances, unce ain y can be p esen wi hin p e e ences o one DM o mo e. Techniques
o handling unce ain p e e ences we e de ised and imp o ed, including unknown
p e e ence, uzzy p e e ence, g ey p e e ence and p obabilis ic p e e ence (Li e al., 2004;
Al-Mu ai i e al., 2008a,b;Kuang e al., 2015;Sil a e al., 2017;Zhao and Xu, 2017;Yu
e al., 2019).
DMs may beha e di e en ly in a dispu e because insigh s and a i udes o isks a y om
pe son o pe son. Consequen ly, ou undamen al solu ion concep s a e p o ided, i.e. Nash
s abili y (Nash), Gene al Me a a ionali y (GMR), Symme ic Me a a ionali y (SMR) and
Sequen ial S abili y (SEQ), along wi h ex ended solu ion concep s such as Symme ic
Sequen ial S abili y (SSEQ), Mixed Symme ic Me a a ionali y (MSMR), Limi ed-mo e
S abili y (L
h
)(Nash, 1950;Howa d, 1971;F ase and Hipel, 1984;Zaga e, 1984;R^
ego and
Viei a, 2017;Zhao e al., 2019).
In e se analysis is a p ocess o de e mine he p e e ences o DMs equi ed o each a
pa icula s a e as a speci ied ou come o desi ed equilib ium in a con lic . Ma ix inequali ies
a e designed o p esen easible egions o p e e ences unde di e en solu ion de ini ions,
and enume a ion and op imiza ion algo i hm a e applied in calcula ion in in e se GMCR
(Kinsa a e al., 2014;Wang e al., 2018;Tao e al., 2021).
Some imes some DMs may o m a coali ion o he pu pose o a be e ou come, and his
coali ion o ma ion inspi ed GMCR esea che s o cons uc GMCR models wi h coali ion
(Kilgou e al., 2001). The applica ion o GMCR is ca ied ou along wi h he de elopmen o
he model. GMCR has been widely used o analyze and se le con o e sies in he ield o
mili a y, en i onmen al go e nance, esou ce alloca ion (F ase e al., 1990;Xiao e al., 2016;
He e al., 2017).
Con lic o
nuclea
was ewa e
discha ging
47
3. The me hod o he GMCR
The g aph model is a model me hod used o sol e he con lic s among di e en DMs.
Di e en DMs ake di e en op ions o s a egies and o m a se ies o easible s a es by
a angemen and combina ion. Each DM has i s own cogni ion o he p e e ence ela ionship
o easible s a es. Each easible s a e can be se ed as a node in he g aph, and one s a e can be
ans e ed be ween o he s a es. The di ec ed a cs linked he di e en s a es a e he op ions
o he DMs, and DMs can con ol hei own ac ions o achie e s a e ha hey wish o mo e o.
The ac ions o he DMs ha e a di ec ion, and some ac ions, once aken, canno be wi hd awn.
In he g aph model, each s a e is a combina ion o op ions chosen by di e en DMs o
achie e hei goals. In ac , he s a egies o each DM ha e hei own selec ed op ions
exp essed as O
1
,O
2
...O
P
. The DM de e mines whe he o selec he op ion, i DM selec s he
op ion which is ep esen ed by “Y”, i DM do no selec he op ion which is ep esen ed by
“N”. The modeling p ocess is shown in Figu e 1. Assuming ha all DMs ha e pop ions, he e
will be 2
P
s a es in ma hema ical logic. Howe e , in p ac ical applica ion, due o some
con adic ions be ween op ions, he numbe o easible s a es is gene ally less han 2
P
.
Based on he desc ip ion o he g aph model me hod, he de ini ion o ma hema ical
language can be gi en. I is assumed ha he e a e mul iple DMs N¼ 1;2;...;ng o
de e mine hei own op ions o o m a s a e se S¼ s1;s2;...;smg, he ansi ion among
s a es can be con olled by he op ions Ak∈S3S aken by any DM k∈N. The mo i e o he
s a e ansi ion is he DMs’p e e ence Pk, o which he ma hema ical exp ession o he
con lic analysis g aph model is as ollows:
hN;S; ðDk;PkÞ:k∈Ngi
A e making clea he DMs, op ions, s a es and p e e ences, ou kinds o equilib ium o
GMCR de ini ions o Nash, Gene al Me a a ionali y (GMR), Symme ic Me a a ionali y
(SMR) and Sequen ial S abili y (SEQ) a e shown as ollows.
De ini ion 1. Nash: Fo any k∈N, a s a e s∈S, and he Nash s able o DM k, as deno ed
by s∈SR
k, i and only i Rþ
kðsÞ¼∅.
Figu e 1.
The modeling p ocess
o he GMCR
MAEM
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48

De ini ion 2. Fo any k∈N, a s a e s∈S, and he GMR s able o DM k, as deno ed by
s∈SGMR
k, i and only i o e e y s1∈Sþ
kðsÞ, he e exis s a leas one
s2∈Sqðs1Þsa is ying s2a
∼s.
De ini ion 3. Fo any k∈N, a s a e s∈S, and he SMR s able o DM k, as deno ed by
s∈SSMR
k, i and only i o e e y s1∈Sþ
kðsÞ, he e exis s a leas one
s2∈Sqðs1Þsa is ying s2a
∼s, and s3∈Skðs2Þsa is ying s3a
∼s.
De ini ion 4. Fo any k∈N, a s a e s∈S, and he GMR s able o DM k, as deno ed by
s∈SSEQ
k, i and only i o e e y s1∈Sþ
kðsÞ, he e exis s a leas one
s2∈Sþ
qðs1Þsa is ying s2a
∼s.
Acco ding o he de ini ion o he ou s abili ies (Nash, GMR, SMR and SEQ), he
in e ela ionships o solu ion concep s a e shown in Figu e 2.
4. The con lic o discha ging o nuclea was ewa e
This sec ion desc ibes he con lic o nuclea was ewa e discha ge in o he ocean, cons uc s
he DMs and hei op ions and analyzes he equilib ium solu ion based on he ela i e
p e e ence o DMs.
4.1 The backg ound o he discha ging o nuclea was ewa e
A e 10 yea s o he Fukushima Nuclea Acciden , Japanese go e nmen and TEPCO
decided o discha ge he nuclea was ewa e in o he Paci ic Ocean o e a cou se o 30 yea s
on 13 Ap il 2021. The wa e (cooling wa e , g oundwa e and ainwa e ) ha cools he eac o
co e is p ocessed by he Ad anced Liquid P ocessing Sys em (ALPS) and s o ed in anks in
he Fukushima Daiichi Nuclea Powe Plan (FDNPP), howe e , all anks will be illed wi h
nuclea was ewa e a ound 2022.
Despi e epea ed assu ances om he Japanese go e nmen ha adia ion le els in he
ea ed and dilu ed nuclea was ewa e a e lowe han hose in no mal d inking wa e , he ac
ha ALPS is weak in handling
14
C and i ium makes hose assu ances un eliable. Once he
nuclea was ewa e con aining adioac i e elemen s is discha ged in o he ocean, i will pose a
g ea h ea o he su ounding ma ine en i onmen , ecological sa e y and human heal h.
Local people, especially hose in ol ed in he ishing indus y, s ongly opposed he
implemen a ion o he decision, because he discha ge o nuclea was ewa e in o he ocean
would g ea ly damage he de elopmen o Japan’s ishing indus y. Meanwhile, Neighbo ing
SMR Nash SEQ
GMR
Figu e 2.
The in e ela ionships
o ou s abili ies
(Nash, GMR, SMR,
and SEQ)
Con lic o
nuclea
was ewa e
discha ging
49
coun ies including China, Sou h Ko ea, Russia, and No h Ko ea exp essed s ong
opposi ion by issuing go e nmen al s a emen s. They a gued ha Japan had mo e ways o
deal wi h nuclea was ewa e , and ha i was i esponsible o unila e ally adop he cheapes
way, which would ha m he ma ine ecological secu i y o su ounding coun ies.
4.2 Decision-make s and op ions
As desc ibed in 4.1, he DMs on he con lic o e he discha ge o nuclea wa e can be
iden i ied as he Japanese go e nmen and TEPCO (JGT), Japanese esiden s (JR) and
neighbo ing coun ies (NC). DMs all ha e hei own op ions, which e en ually o m easible
s a es as shown in Table 1.
Acco ding o Table 1, he h ee op ions o JGT a e discha ging nuclea was ewa e in o he
ocean, discha ging nuclea was ewa e by o he me hods and s o ing nuclea was ewa e .
JR’s op ion is esis ing o discha ging nuclea was ewa e in o he ocean and NC’s op ion is
imposing sanc ions on he ma ine indus y o JGT. And he in eg a ed g aph o he con lic
o discha ging o nuclea was ewa e is shown in Figu e 3.
DM1 JGT
Discha ging nuclea was ewa e in o he ocean Y N Y N Y
Discha ging nuclea was ewa e by o he me hods N Y Y N N
S o ing nuclea was ewa e N N N Y N
DM2 JR
Resis ing o discha ging nuclea was ewa e in o he ocean N N N N Y
DM3 NC
Imposing sanc ions on he ma ine indus y on JGT N N N N N
S a es S
1
S
2
S
3
S
4
S
5
DM1 JGT
Discha ging nuclea was ewa e in o he ocean Y Y Y Y Y
Discha ging nuclea was ewa e by o he me hods Y N Y N Y
S o ing nuclea was ewa e N N N N N
DM2 JR
Resis ing o discha ging nuclea was ewa e in o he ocean Y N N Y Y
DM3 NC
Imposing sanc ions on he ma ine indus y on JGT N Y Y Y Y
S a es S
6
S
7
S
8
S
9
S
10
Table 1.
The easible s a es in
he con lic o
discha ging o nuclea
was ewa e
Figu e 3.
The in eg a ed g aph
o he con lic o
discha ging o nuclea
was ewa e
MAEM
5,1
50
Theo e ically, he e a e i e choices o he h ee DMs, which can o m 2
5
532 s a es in
o al, which a e ma hema ically possible. Howe e , he e may be con adic ions in DMs’
op ions and some o he 32 s a es a e in easible. In FDNPP nuclea was e wa e discha ging
con lic , JGT has o choose a leas one o i s h ee op ions. I JGT does no selec he op ion
ha discha ging nuclea was ewa e in o he ocean, JR canno selec he op ion ha esis ing
JGT, and NC canno selec he op ion ha imposing sanc ions on he ma ine indus y o JGT.
Besides, JGT’s op ion o “discha ging nuclea was ewa e in o he ocean”con lic s wi h he
one o “s o ing nuclea wa e ”.I ’s also in easible i JGT choose bo h o discha ge nuclea
was ewa e in o he ocean and o he me hods conside ing he p ocessing cos . Acco ding o
Minis y o Economics, T ead and Indus y (METI) o Japan, compa ed o o he op ions such
as “injec ion and disposal in o he geological o ma ion”,“ elease o he A mosphe e in he
o m o s eam”and “unde g ound bu ial and disposal a e solidi ica ion o geli ica ion”,
“ elease o he sea”is he me hod wi h lowes cos .
4.3 Decision-make s’p e e ences
In he GMCR, he DMs’p e e ences a e he mo i e o he s a e ansi ion, and DMs ealize
hei own in e es s by changing hei own op ions. Acco ding o he esea ch g oup o
MEIT’s epo on Ap il 19, 2016, MEIT had conside ed a ious me hods such as sealing he
sewage wi h conc e e a e pu i ica ion ea men , bu ying i unde g ound o allowing i o
e apo a e in o he a mosphe e, bu he cos o ens o billions o hund eds o billions o yen
de e ed he go e nmen . I only cos s 1.7 billion o 3.4 billion yen o discha ge he dilu ed
i ium esidual wa e in o he ocean, which is e y a ac i e in cos . The epo also said ha
discha ging nuclea sewage in o he sea means ha i can be comple ely ea ed in only 4–
8 yea s, which is qui e “cos -e ec i e”in e ms o ime. So JGT hopes o discha ge nuclea
was ewa e in o he ocean, which will g ea ly sa e JGT expendi u es. A he same ime, JGT
does no wan o be boyco ed by JR and sanc ioned by NC. Neighbo ing coun ies such as
China and Sou h Ko ea ha e announced boyco s agains he impo o aqua ic p oduc om
Japan, causing se ious h ea s o Japanese Fishe ies (Wu e al., 2020). I he e is s ong
opposi ion and sanc ions, JGT is mo e inclined o con inue o s o e nuclea was ewa e
ins ead o adop ing o he me hods o ea nuclea was ewa e , because i will incu huge
expendi u es.
JR does no wan JGT o discha ge nuclea was ewa e in o he ocean, which will no be
conduci e o he de elopmen o local ishe ies. JR does no wan NC o impose ishe y
sanc ions on JGT. JR hopes ha i is he igh choice o JCT o dispose o nuclea was ewa e
in a pollu ion- ee manne . Fo NC, NC hopes o impose sanc ions on JGT ishe ies o o ce
JGT no o discha ge nuclea was ewa e in o he ocean. NC also hopes JR oppose JGT. The
p e e ence ankings o each DM a e shown in Table 2.
4.4 Equilib ium analysis
Acco ding o he p e e ence ankings o he h ee DMs, combined wi h he de ini ion o Nash,
GMR, SMR and SEQ equilib ium o he GMCR, he equilib ium solu ion o he con lic o he
discha ging o nuclea was ewa e is shown in Table 3.
DM P e e ence ankings
JGT S
1
>S
4
>S
3
>S
7
>S
5
>S
8
>S
6
>S
9
>S
10
>S
2
JR S
4
>S
2
>S
6
>S
5
>S
10
>S
9
>S
3
>S
1
>S
8
>S
7
NC S
2
>S
4
>S
10
>S
8
>S
9
>S
7
>S
6
>S
3
>S
5
>S
1
Table 2.
The p e e ence
ankings o each DM
Con lic o
nuclea
was ewa e
discha ging
51
In Table 3, he s a e ep esen ed by “√”indica es ha a s abili y o DM indi iduals. I a
s a e is he s abili y o all DMs, hen he s a e is he equilib ium solu ion o he con lic . F om
Table 3, he equilib ium solu ion o he con lic p oblem o nuclea was ewa e discha ge is S
9
and S
4
,S
9
sa is ies he ou equilib iums and S
4
sa is ies he h ee equilib iums o GMR, SMR
and SEQ.
In he S
9
, JGT selec s he op ion o discha ging nuclea was ewa e in o he ocean, JR
exp esses opposi ion and NC imposes sanc ions on JCT. The si ua ion e lec ed in S
9
is
consis en wi h he cu en con lic si ua ion. In his s a e, al hough he discha ge o nuclea
was ewa e in o he ocean can alle ia e he inancial p essu e o JGT in a ela i ely sho
pe iod o ime, he pollu ion caused by he ma ine en i onmen is i e e sible. I will also
se iously a ec JR’s li e heal h and economic income. Simila ly, he discha ge o nuclea
was ewa e will also a ec he ma ine en i onmen o neighbo ing coun ies and e en he
wo ld. In o de o main ain he sa e y o i s people, NC has o impose sanc ions on JGT’s
sea ood, which will also wo sen diploma ic ela ions and cause g ea e economic losses.
In he S
4
, JGT selec s he op ion o s o ing nuclea was ewa e , while bo h JR and NC
exp ess hei suppo . In his s a e, al hough JGT will inc ease s o age cos s o a ce ain
ex en , i p o ec s he ma ine en i onmen , gua an ees JR’s heal h and economic income and
enhances JGT’s diploma ic epu a ion, which is mo e conduci e o in e na ional coope a ion
wi h NC. Economic ounda ion and in e na ional ela ions p o ide echnical gua an ee o
mo e en i onmen ally iendly ea men o nuclea was ewa e in he u u e.
5. Conclusion
The con lic o nuclea was ewa e discha ge in Japan is a complex p ocess, and he e a e a lo
o unce ain ies and unknowns in his p ocess. I is di icul o quan i y he e ec unc ion o
each DM by game heo y me hod, while he GMCR me hod can sol e he con lic p oblem by
analyzing he ela i e p e e ence o DMs. In his s udy, GMCR me hod is used o sol e he
nuclea was e wa e discha ge p oblem.
The esul s show ha S
4
and S
9
a e he equilib ium solu ions o sol e he con lic p oblem,
and S
9
is in consis wi h he cu en si ua ion. F om a long- e m pe spec i e, his equilib ium
is un a o able o all DMs including JGT i sel .
I is wo h no ing ha S
4
is ano he equilib ium in his g aph model, which indica es ha
JGT o s o e he was e wa e is a po en ial ou come o he dispu e in eal wo ld. In ac ,
Fukushima P e ec u e s ill has enough space o s o e nuclea was e wa e , and o he op ional
p ocessing me hods a e a ailable. Compa ed o S
9
,S
4
is an equilib ium o JGT wi h ega d o
he solu ion concep s men ioned abo e excep o Nash Equilib ium, which means ha JGT
has he in en ion o lea e S
4
wi hou conside ing o he DMs’sanc ions. Vice e sa, i JR and
S a es
JGT JR NC
Nash GMR SMR SEQ Nash GMR SMR SEQ Nash GMR SMR SEQ
S
1
√√√√
S
2
√√√√√√√√
S
3
S
4
√√√√√√√√√√√
S
5
√√√√√√√√
S
6
√√√√√√√
S
7
√√√√ √√√√
S
8
√√√ √√√√
S
9
√√√√√√√√√√√√
S
10
√√√√√√√√
Table 3.
The equilib ium
solu ion o he con lic
o he discha ging o
nuclea was ewa e
MAEM
5,1
52