43
1 INTRODUCTION
Safety isa basic priority of waterway transportation
(Liu et al, 2016). The determination of clear area
around the ship is mainly important for safe
navigation(WangandChin,2015).Safenavigationis
an ever‐growing issue, especially due to the rapidly
increasingnumbersofships,andimprovingma
ritime
industry. Even though statistics display developed
levelsofsafetyintheindustry,whichcarries90%of
the world trade, the risk of navigational incidents
remainsamajorconcernandpriority(Baldaufetal.,
2015).
The concept of collision avoidance helps to
eliminate these risks. It is important the analysis of
ship collision risk, probabilit
y of occurrence, the
understanding of collision probability and possible
results of collisions (Tang et al., 2013). Making
collision risk assessment is the main issue in the
decision systems, and it is a major concept in
navigation(XuandWang,2014).Aresearchprepared
bytheNauticalInstitute(NI)demonstratedtha
t60%
ofcollisionandgroundingcasesarecausedbydirect
human error (Gale and Patraiko, 2007) on the other
hand, the statistics show that human errors have
caused 80% of marine incidents for which the basic
reasonisimproperdeterminationsofthenavigational
case and the result incorrect decisions (Wang et al.,
2009). The two ma
jor human involved causes are
“inadequate determination of the situation” (24%)
and “ineffectual look out” (23%) navigation (Wang
andChin,2015).
Mostoftheshipdomainmodelsaredefined ina
geometricalmannerwhich is easy to grasp however
not conducive for applicat
ion to practices or
simulations.Therefore,thereisaneedfora uniform
analyticalframeworktodescribeshipdomainmodels
A Research on Concept of Ship Safety Domain
A.Baran,R.Fışkın&H.Kişi
DokuzEylülUniversity,İzmir,Turkey
ABSTRACT:Thisstudypresentstheresultsofthecontentanalysisofa
rticlesrelatedtoʺShipSafetyDomainʺ.
Thecontentandstatisticalanalysisof44articlesthatpublishedin21differentjournalsbetween1970and2016
wereconducted.Thisstudyincludesvariousdatatypessuchaspublishing yearsofarticles, obt
ainingthetype
ofdata,thecontributionofauthors,thecontributionofcountries,thecontributionoftheinstitution,therankof
thejournal,keywordsofarticlesandetc.Thecontentanalysisaimstoprovidenecessaryindicatorsforreaders,
followers,andcontributorsofrelevantdisciplineandaglimpseoflot
sofarticles.Thepublishedarticlesabout
ship safety domain are discovered by this study so as to contribute lecturers and researchers interested in
navigationespeciallyshipdomainconcept.TheresultsoftheresearchwererevealedthatPolandandChinaare
themostcontributingcountries,DalianMaritimeUniversityandTheMaritimeUniversityofSzczecinarethe
mostcontributinginst
itutionsandNingWangandRafalSzlapczynskiarethemostcontributingresearchers.
http://www.transnav.eu
the International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 12
Number 1
March 2018
DOI:10.12716/1001.12.01.04
44
inorderthatthesemodelscouldplayapowerfulrole
inmarinetrafficengineering(Wangetal.,2009).
During the ship navigation, the safety zone is
referred as the ship domain. Any infringing of the
shipdomainisevaluatedasadangertonavigational
safety (Pietrzykowski and Uriasz, 2009). A
ship
domainiscommonlythoughtasthespacearoundthe
ship,whichtheOOW(OfficeroftheWatch)wantsto
keep clear of other objects. (Szlapczynski and
Szlapczynska,2015).Shipdomainsarepowerfuland
primaryaccessestodealingwithshipnavigationrisk
determination,withcollisionavoidance,withmarine
traffic simulations
and with optimal trajectory, etc.
Manyresearchershavesubmittedshipdomainstype
with various dimensions and shapes in the past
decades (Wang, 2013). Ship domain capacity (shape
and size) generally depends on shipʹs speed and
length although parameters of other ships may also
beconsidered(SzlapczynskiandSzlapczynska,2015).
The
concept of ship domain is crucial for safety
navigationso,inthiscontext,theaimofthisstudyis
tomakea contentanalysisof articlesrelated to ship
safety domain in related literature to guide the
academicians and researchers study in the related
field.
2 ACONCEPTOFSHIP
DOMAIN
Variousshipdomainshavebeenpresentedbymany
researchers having taken into account different
shapesandsizes.Thedeterminationofshipdomains
stronglydependsonthestatisticaldataandoperator
experience. It is found that the ship domains
described by geometrical figures including ellipse,
polygon,circleandothercomplexfigures
ratherthan
analyticalmanner.Thecircularshipdomainproposed
by Goodwin (1975) which is divided into three
sectors. The model is also obtained from statistical
methods from a great number of records and
simulatordata.Theothertypeofshipdomaincalled
as elliptical ship domain is proposed by Fuji
and
Tanaka (1971). The domain is created by using
statisticalmethods.Coldwell(1983)proposedanother
elliptical ship domain by similar statistical methods
forheadonandovertakingsituations.Polygonal ship
domain proposed by Pietrzykowski (2004, 2006) is
also another important type of ship domain. The
domain depends on the determination of
dynamic
functionsofshipdimensions andspeed(Wangetal.,
2009).
3 METHODOLOGY
In this study, 44 articles that were published in
various journals between 1970 and 2016, were
performed to make a content analysis. This analysis
was separated into various categories such as the
contributing of authors, the rank
of the journal,
keywords of articles and etc. When applying
statisticalanalysis,computer‐assisted Statistical
Package for the Social Sciences (SPSS) software was
utilized.
Acontentandstatisticalanalysiswereadoptedfor
44 articles based on ship safety domain. First of all,
we determined categories as authors, countries,
institutions,journals,keywords,
wordsinthearticles
namesandyearstoapplyanalysis.
Thebasicaimofthisstudyistoguideresearchers
who will study about ship safety domain and assist
furtherstudiesthatwillbeutilizedintheshipsafety
domainresearcharea.
4 FINDINGS
4.1 Authorsstatistics
Articles in the
related field prepared by commonly
double and more authors. As seen in Figure 1 and
Table1,18,2%ofarticlespreparedbydoubleauthors
and40,9%ofarticlespreparedbymultipleauthors.
Figure1. Distribution of the articles according to authors
group.
Table1.Thenumberofauthorsinarticles.
_______________________________________________
TheNumberofAuthorsinArticles (f) (%) C (%)
_______________________________________________
Single18 40,9 40,9
Double8 18,2 69,1
Multiple18 40,9 100,0
_______________________________________________
Total44 100,0
_______________________________________________
Table2.Themostcontributingauthors.
_______________________________________________
AuthorRank (f) (%) C(%)
_______________________________________________
NingWang1 6 5,85,8
RafalSzlapczynski2 5 4,810,6
ZbigniewPietrzykowski3 4 3,814,4
KrzysztofMarcjan4 3 2,917,3
FengZhou5 2 1,919,2
JingxianLiu6 2 1,921,2
LucjanGucma7 2 1,923,1
MirosławWielgosz8 2 1,925,0
PaulVernon
Davis9 2 1,926,9
Q.Y.Hu10 2 1,928,8
Others74 7 1,2100,0
_______________________________________________
Total80 104 100,0
_______________________________________________
45
The most contributing ten authors are listed in
Table 2 and Figure 2.ʹNing Wangʹ is the most
contributingauthorwithinatotalof80authorswith6
articles. Followed by Rafal Szlapczynski with 5
articlesandZbigniewPietrzykowskiwith4articles.
Figure2.Themostcontributingauthors.
4.2 Bibliometricstatistics
A total of 44 selected articles were published in 21
differentjournals.“TheJournalofNavigation”isthe
mostcontributingjournalwithatotalof17articles.
Table3.Themostcontributingjournals.
_______________________________________________
JournalRank (f) (%) C(%)
_______________________________________________
TheJournalofNavigation1 17 38,6 38,6
JournalofDalianMaritimeUniversity 2 3 6,854,5
Ship&OceanEngineering3 2 4,5 65,9
ActivitiesinNavigation4 1 2,368,2
AnnualofNavigation5 1 2,370,5
InformationProcessingandSecurity 6 1 2,3 75,0
Systems
JournalofWuhan
Universityof7 1 2,3 77,3
Technology
Missingvalue1 2,3 79,6
Others17 38,6 100
_______________________________________________
Total21 44 100
_______________________________________________
All articles are separated according to 5‐years
period to simplify cluster. According to analysis
results, Studies in related field showed a rapid
increase since 2000. While a total number of studies
that published between 1970‐2000 is equal to 6, 35
articles were published after 2000. The most
contributing period is 2011‐2016 with the total of 24
studies. On the other hand, no studies have been
conducted between 1991 and 1995. Following the
recession,alargeincreasewasobserved
.
Figure3.Themostcontributingjournals.
Table4.Distributionofarticles(5‐yearperiod).
_______________________________________________
Year(f)  (%) C(%)
_______________________________________________
1970‐19751 2,22,2
1976‐19801 2,24,4
1981‐19851 2,26,7
1986‐19901 2,28,9
1991‐19950 0,08,9
1996‐20002 4,413,3
2001‐20053 6,720,0
2006‐201011 26,7 46,7
2011‐201624 53,3 100,0
Total44  100
_______________________________________________
Figure4.Distributionofarticles(5‐yearperiod).
4.3 Affiliationstatistics
Geographicallocationsofcontributinginstitutionsare
showninFigure5.Themostcontributinginstitutions
areinChinaandPoland.DalianMaritimeUniversity
is the most contributing institution followed by
Maritime University of Szczecin. Both of them
accountedfor34,1%ofallarticles.
China is the most contributing country
with the
total of 17 articles and approximately half of them
were conducted by Dalian Maritime University.
FollowedbyPolandwith thetotalof 16articlesand
approximatelyonethirdofthemwererealizedbythe
Maritime University of Szczecin. China and Poland
accountedfor75%ofallcountries.
46
Figure5. The geographical distribution of contributing
countries.
Table5.Themostcontributinginstitutions.
_______________________________________________
CountryRank (f)  (%) C(%)
_______________________________________________
China1 17  38,6 38,6
Poland2 16  36,4 75,0
Sweden3 2 4,579,5
UK4 2 4,584,1
USA5 2 4,588,6
Denmark6 1 2,390,9
Japan7 1 2,393,2
Singapore8 1 2,395,5
Slovenia9 1 2,397,7
Taiwan10  1 2,3100,0
Total
10  44 100,0
_______________________________________________
Figure6.Themostcontributinginstitutions.
Table6.Themostcontributingcountries.
_______________________________________________
InstitutionRank (f) (%) C(%)
_______________________________________________
DalianMaritimeUniversity1 8 18,2 18,2
MaritimeUniversityofSzczecin 2 7 15,9 34,1
WuhanUniversityofTechnology 3 5 11,4 45,5
GdanskUniversityofTechnology 4 5 11,4 56,8
GdyniaMaritimeAcademy5 4 9,1 65,9
ShanghaiMaritimeUniversity 6 3 6,872,7
NationalMaritimeResearchInstitute7 2 4,5
77,3
WorldMaritimeUniversity8 1 2,3 79,5
NationalUniversityofSingapore 9 1 2,3 81,8
NationalKaohsiungMaritime 10 1 2,3 84,1
University
MissingValue1 2,386,4
Others6 13,6 100,0
Total17 44 100,0
_______________________________________________
Figure7.Themostcontributingcountries.
4.4 Keywordstatistics
Thewordsusedinarticletitlesareanalyzedinorder
to reveal the most used words.ʹDomainʹ (37) and
ʹShipʹ(34)arerevealedasthemostutilizedwordsas
shown in Table 7. and Figure 8. According to
keywordsanalysis,ʹCollisionavoidanceʹ(8)andʹship
domainʹ (7)
is the most used keywords within 70
keywordsasshowninTable8.andFigure9.
Table7.Thewordsusedinarticletitles.
_______________________________________________
Thewordsinthearticletitles Rank (f) (%) C(%)
_______________________________________________
Domain1 37 11,6 11,6
Ship2 34 10,7 22,3
Collision3 12 3,826,0
Area4 9 2,828,8
Safety5 9 2,831,7
Model6 8 2,534,2
Risk7 7 2,236,4
Based8 6 1,938,2
Water9 6 1,940,1
Assessment10 5 1,641,7
Others
286 58,3 100,0
_______________________________________________
Total133 319 100,0
_______________________________________________
Figure8.Thewordsusedinarticletitles.
47
Table8.Thekeywordsusedinarticle.
_______________________________________________
KeywordsRank (f) (%) C%
_______________________________________________
Collisionavoidance1 8 9,39,3
Shipdomain2 7 8,117,4
Collisionrisk3 3 3,520,9
Restrictedarea4 2 2,323,3
DCPA5 1 1,224,4
3DModel6 1 1,225,6
Accidentprevention7 1 1,226,7
AISdata8 1 1,227,9
Analyticalmodel9 1
 1,229,1
Approachparameters10 1 1,230,2
Others60 69,8 100,0
_______________________________________________
Total70 86  100
_______________________________________________
Figure9.Thekeywordsusedinarticle.
5 CONCLUSION
In the literature related toʹShip Safety Domainʹ,
Poland and China are revealed as the most
contributingcountries.Ontheotherhand,thereisno
studypreparedbymajor maritimecountriessuchas
Turkey,Netherland,Germanyandetc.TheJournalof
Navigation is the most contributing journal as
expectedbecause thejournal isbasedon navigation.
The most productive periods are revealed asʹ2011‐
2016ʹ andʹ2006‐2010ʹ. This shows that the topic has
become a popular topic in recent years. Dalian
Maritime University and Maritime University of
Szczecinarethemostcontributinginstitutions.China
isintensely
interestedin thetopicand Poland isthe
most contributing country in EU region.ʹCollision
avoidanceʹ andʹShip domainʹ are the most used
keywords as expected. Similarly, the words that are
most used in article titles areʹDomainʹ,ʹShipʹ and
Collisionʹ. It is revealed that the most contributing
authors
areʹNing Wangʹ,ʹRafal Szlapczynskiʹ andʹ
Zbigniew Pietrzykowski’, respectively. Especially,
researchers from China and Poland are mostly
interestedinthetopic.
Asaresult,thereisaveryfewstudyintherelated
field.Itisthoughtthatnewresearcherscanfocuson
thetopic.This isbecausethe
shipnavigation canbe
saferifmoreresearchersareinterestedinthetopic.
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