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officer on watch (OOW) and the helmsman. It
escalates in different traffic and environmental
situation. Indeed, the system hardly relays on the
OOW’s capacity to decide on appropriate action. This
implies the necessity of proper performance
adjustment to maintain the system works normally
under dynamic working condition. In this case,
human adaptability and flexibility are essential to
achieve this kind of purpose. The definition of safety
in this manner is introduced by a term called Safety-II
[7]. Hence, under this consideration, it is important to
understand deeper this adaptable performance more,
in specific of how the fluctuation affects system
output.
The application of FRAM in this study is to
identify the functional basis of ship maneuvering
activity and provide a systematic expression of it
through functions and potential couplings. Analysis
in FRAM is qualitative in nature. It provides an
explicit understanding of the system’s functionality in
the form of FRAM model but lacks in function’s
performance representation. One solution that can be
applied is cooperating with the method of
quantitative analysis. Some available studies have
existed regarding this matter, such as the application
of Monte Carlo evolution [3] and modified Fuzzy
FRAM-CREAM with cellular automata simulation [8].
Therefore, in addition to the FRAM, this study
employs a Dynamic Bayesian Network (DBN) for
mathematical modeling. DBN is an extended version
of the Bayesian Network (BN). It is a type of
probabilistic graphical model that can be used to
model complex, dynamic systems over time. BN has
been widely applied in the maritime industry,
especially to predict the probability of ship accidents
[9]–[11]. One of the advantages of DBN is this method
can handle temporal dependencies and allow for the
modeling of time-varying influences on system
behavior. The basic idea of this quantitative
expression is to model the discrete probabilistic
dependencies between functions at each point in time,
and then to propagate these dependencies over time
to express a dynamic change in the system.
A case study from ship handling simulation has
been chosen to perform the analysis. The FRAM-DBN
integration in this study aimed to develop a
comprehensive model of ship officer variability
performance, providing insights into how changes in
officer performance over time influence system
output. The meaning of using this specific case is to
provide actual-time segregation for every decision
initiative and actual evidence of performance for DBN
analysis. Furthermore, the FRAM model can also be
built for a specific instantiation. This is a simple
analysis that design to present what to expect from
performance adjustment, and how can normal
performance be disrupted and then produce
undesired outcomes. In conclusion, the essence of
human performance for establishing an adapted
system can be addressed, and what strategy must be
built to enhance it to possess a higher level of
resilience.
2 METHOD
This section explains a set of methods applied in this
study. First is the qualitative analysis using FRAM
and build the FRAM model. Second is integrating the
FRAM analysis with quantitative analysis based on
DBN. In addition to that method integration, the
control model from Cognitive Reliability and Error
Analysis Method (CREAM) has been brought to
provide characteristic for FRAM function. This
characteristic includes strategic, tactical,
opportunistic, and scrambled.
2.1 FRAM as a retrospective analysis
The FRAM [12], [13] has been widely implemented to
assess system safety in various fields. System
resilience [2] terminology, as a core of FRAM,
promotes new ideas for safety research by
acknowledging safety as an emergent phenomenon
instead of a property of the system. This implies the
need on looking for what was done in the everyday
operation of the system (Work-As-Done) and how
safety is present in the system. The term function is
used to express the need for something to be done by
the system. The function is classified into three
categories including human, technological, and
organization. FRAM has four basic principles,
including the equivalent of success and failure,
approximate adjustment, the principle of emergence,
and functional resonance.
Function in FRAM is presented as a hexagon with
six aspects to characterize the type of information in
function’s dependency. Input represents the
information or material to trigger the process in
function. Precondition refers to the conditions that
exist prior to the function starting its operation. In this
sense, precondition is complementary information
that explains the pre-event or preparation that has
been done before a function is carried out. Time is the
temporal dimension of the function, including the
timing and sequencing of events. Control represents
the mechanisms used to control the function,
including procedures, rules, and policies. Resource is
something that is used or consumed by the function,
including energy, competence, people, tools,
materials, etc. The output represents the results of the
function’s work. Outputs can be seen as a signal that
starts a downstream function.
The relationship of function is described in two
forms. First is temporal relationships, namely
upstream and downstream functions. This expresses a
function’s dependency on specific time observation.
The downstream function is affecting the process that
happened in the downstream function, and this role
can change over time based on the potential coupling
and time of function activation. Second, the general
role of background and foreground functions.
Background function presents a function that only has
output or input as its aspect. It means the function is
only affecting the other functions in the system. On
the other hand, the foreground function is a function
that has more than 1 aspect. This function receives
information from background or foreground
functions, and also produces an output for other
foreground or background functions. In other words,