disaster, maintaining safety of traffic and so on.
As one of these researches to support a practical work concerned with
marine traffic, an investigation into the actual traffic condition with radar equipment
had been started before a quarter of century. The statistical result of this investigation
gave us a lot of basic information about a marine traffic environment. However, statistics
obtained from these investigation are not sufficient to make clear the bound of human
abilities because of lacking of subjective evaluation from a navigator's standpoint.
Recently, simulation and simulator techniques are becoming useful to assess human factors
according with the development of the computers. Fig.2 shows the basic viewpoint to assess
maritime traffic environment. So, the progress of researches done with many researchers
who belong to Japan Institute of Navigation or done with our cadets as a graduation thesis
to assess maritime traffic environment was introduced successively.
Fig. 1 An outline of the educational system
throughout the four and half years at
Maritime Safety Academy.
Fig.2 The basic viewpoint of the research
to assess maritime traffic environment.
2. OBSERVATIONS OF ACTUAL TRAFFIC
To grasp actual traffic condition, Maritime Safety Agency had been
carrying out an observation for a long time at congested area and the obtained data had
been summing up and analyzing by the stuffs of the academy. An observation using a radar
and a visual observation were carried out at the same time. The radar observation mainly
gives us a lot of tracks of passing vessels and the visual one was used to identify the
tonnage and the kind of these tracks. Of course these data were translated into a digital
data to be acceptable by the computer.
As ordinary output of this database, four kinds of chart were drawn up:
an accumulated tracks chart about each class of tonnage or each kind of vessels, a bar
graph
