597
1 INTRODUCTION
Koreaʹs VTS (Vessel Traffic Service) is currently
installedin15portsand3coastalareas,inorder to
maintainmarinetrafficsafetyusingradar,VHF,AIS,
etc., and to protect the marine environment. VTS
monitors identified vessels in the VTS area and
provide the necessary information. As a result of
theseeffort
s,marinecasualtieswerereducedby39.3
%, from 126.6 cases to 76.8 cases after the
establishment of the VTS (Kim, 2015a). However,
therearestillmarinecasualtiesintheVTSareaand
there is no quantitative VTS officer’s control
guideline,sothattheserviceuser,theshipoperator,
ma
yreceivedifferentservicesaccordingtotheVTSO
evenunderthesamecircumstances.
IntheVTSarea,generalreportingsuchasarrival,
departures,andpassageofvessels,aswellasspecific
instructions on vessel traffic, are made by the VHF
control channel. Therefore, it is possible to analyze
communicationpa
tternofVTSOandmovementofa
shipthroughcommunicationanalysisofVTSarea.
We have obtained various information by
analyzing the communication of the VTSO (Kim,
2015b)andproposedthecontroldistancethroughthe
communicationanalysis(Park,2015).However,there
is no study on the probability of the dangerous
control through the communication analysis or the
minimumsafetydomainoftheVTSO.
Inthi
spaper,weanalyzedthecommunicationin
theVTSareaanddrewtheprobabilityofoccurrence
ofthecommunicationofthedangeroussituationby
the VTSO, and suggested the guideline of the
quantitativecontrolbydrawing theminimumsafety
domain.
For thi
s purpose, Busan Port, which has the
largest number of vessel traffic in Korea, has been
monitored for 7 days and the shipʹs AIS data were
collected to confirm the risk level at the time of
communication.
Themonitoring frequency ofthe dangerous ship
wasconfirmedtofollowthePoissondistributionand
the int
erval of the control was calculated using the
A Study on Basic VTS Guideline based on Ship’s
Operator’s Consciousness
S.W.Park,Y.S.Park&J.S.Park
KoreaMaritimeandOceanUniversity,Busan,Korea
ABSTRACT: VTS controls vessels using VHF for 24 hours a day. Therefore, from the analysis of VHF
communication,wecanunderstandthecurrentstatusofmarinetrafficandVTS’scontrolpatterninVTSarea.
This study objective is to propose a basic VTS guideline with ship’s CPA/TCPA, collision risk, control
frequency,and minimumsafetydistance usinganalysis of VHFcommunication. We analyzeda 7 dayVHF
communicationand AIS data from Busan VTSarea, thereafter calculatedrisk of collision using Park model
whichisba
sedonshipoperator’sconsciousnessandplottedminimumsafetydistanceandvessel’shighrisk
controlfrequencyusingPoissondistribution.
http://www.transnav.eu
the International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 11
Number 4
December 2017
DOI:10.12716/1001.11.04.04
598
exponential distribution. In addition, the minimum
safety domain of the VTSO was drawn using the
bearing and distance at the time of control of the
dangerousships.
2 VHFCOMMUNICATIONANALYSISINBUSAN
PORTVTSAREA
2.1 Researchmethodsandtargets
InoueandHara(1973)suggestedthat6to7
daysof
marinetrafficobservationwould be appropriatefor
representativepopulation.
Based on this reason, we analyzed the
communicationofVTSOintheBusanPortareaand
identifiedthedangerousencountersofthevesselsfor
3days(6
th
April,2015~8
th
April,2015),forfourdays
(11
th
December2015~14
th
December2015),atotalof
7 days (168 hours). We also collected the AIS
informationoftheshipatthesametimetocalculate
themaritimetrafficrisk.
Figure1.BusanportVTSarea.
2.2 RiskmodelbasedonShipOperatorConsciousness
VTSOuseCPAandTCPAinmanycases,butthisis
the value indicated by the distance, speed, and
heading factors between the vessels. However, it is
commonfortheship’soperatortodeterminetherisk
betweenvesselsbyreflectingthefactorssuch
asthe
size of the vessel, the type of the vessel, and the
surroundingsearoom.
Therefore,thisstudyintendstousethePotential
Assessment of Risk (PARK) model, which is
implemented for the risk of the ship operator who
navigates the actual coastal waters of Korea. PARK
modelis
basedontheshiptype,tonnage,shiplength,
ship width, angle and direction of approaching the
ship, the relative speed of ships and the distance
betweenships(Parketal.,2015).
Therisk ofthe PARKmodel rangesfrom 1 to7,
with0to3beingsafe.3to5
areclassifiedassafeand
not dangerous, and 5 or more are classified as
dangerous. In this paper, we analyzed the control
communication with a risk value of 5.0 or more,
whichisconsideredtobeadangeroussituation.
2.3 Identificationofrisksituationbasedon
communicationanalysisofBusan
PortVTS
The communication in Busan Port VTS area was
classifiedasVTStoship,shiptoVTSandshiptoship
calls.Theamountofcommunicationwasanalyzedas
showninTable1for7days.
Table1. Number of communication via VHF Ch.12 in
7days
_______________________________________________
Day ShiptoVTS VTStoshipShiptoship Total
_______________________________________________
1
st
day 73914393882
2
nd
day 702132102 834
3
rd
day 787149118 936
4
th
day 5539962652
5
th
day 64117288813
6
th
day 847135130 983
7
th
day 853167981,020
_______________________________________________
Total 5,122998691 6,811
_______________________________________________
Atotalof6,811communicationswereconducted
on the VTS VHF channel 12 of Busan Port for a
period of 7 days. The average number of
communication per hour was 40.54 at every 1.5
minutes. To identify the case where the VTSO
instruct the vessels directly, among the contents
of
the VHF channel No.12 of the Busan Port VTS, the
analysis was divided into 7 items: control, radio
check, intention, information, vessel check, channel
change and others. To identify the case where the
VTSOmonitorstheshiptoshipcommunication,the
analysiswasdividedinto4items:intention,channel
change,
chat,andothers.
Table2.NumberofVTScommunicationitemsin7days
_________________________________________________________________________________________________________
TimeControl RadioCheck Intention Info. VesselCheck ChannelChange etc. Total
_________________________________________________________________________________________________________
00000200 1801962238
02000400 1203641026
04000600 1602980439
06000800 8607199112134
08001000 4416301018100
1000
1200 433224112590
12001400 470524143598
14001600 480419150894
16001800 68052515211126
18002000 81071214212128
2000
2200 30068601060
22002400 350115120265
_________________________________________________________________________________________________________
Total528 4492001241479998
_________________________________________________________________________________________________________