electronic warfare self-protection of battlefield helicopters - Aaltodoc

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disadvantage is that understanding of the factors that have contributed to the result
requires detailed mathematical insight into the problem. In order to make the
problem more understandable, mathematical tools have to be supported either by
drawings or by models that explain intricacies and alternatives.
2.4 Conclusions on methods
Conclusions of the discussion in Section 2.3 are summed up in Table 3. One
conclusion drawn from the table is not to use Checkland’s SSM in the present work.
Further, mathematical tools will be used, if needed, only in a supportive role.
Qualitative methods will be preferred over quantitative methods, but simulation will
be used if a specific advantage can be expected from it. As mentioned in Section
2.3.7, FSD is the only simulation tool that has been considered. The main reason for
this choice is that the results of the present work are intended for use in a multitude
of situations, and for communication with people of different backgrounds, and the
methods should be kept at the simplest possible level. Figure 7 shows that data flow
diagrams and CLDs can be used to model similar processes or systems. Since CLDs
are less well known in the engineering community the decision is mainly to build
qualitative models using DFDs. The bulk of the information in this study will be
presented through the “traditional methods”, but the extent to which they are useful
for presenting the holistic view on EWSP of battlefield helicopters must be judged
when discussing the entire work.
Section Conclusion
2.3.1
and
2.3.2
Quantitative methods (simulations) are preferable when access to numerical data is
painless and the data is reliable, qualitative methods (modeling) are to be preferred for
unstructured problems and when data is not available. In equivocal cases the continuum of
OR methods (Figure 5) can be a guide.
2.3.3 No single alternative presented in Table 1 can be assessed to satisfy the requirements alone
for forming a holistic view on EWSP.
2.3.4 The “traditional methods” are “traditional” because of their inherent strengths; hence they
maintain their position in many forms of communication. The major weakness is the
demand that textual information puts on participants.
2.3.5 Despite differences both DFDs and CLDs are possible modeling tools for the present
work. The resemblance between the DFD and CLD raises the question of what changes are
needed to use DFDs in connection with FSD models instead of CLDs.
2.3.6 Checkland’s SSM has merits in facilitating group discussions on unstructured problems,
but application of Checkland’s SSM to the present work would shift the focus from EWSP
to SSM methodology.
2.3.7 FSD is intended for simulation of general systems, and is as such applicable to a wide
range of problems. It has inherent limitations that could be a problem for the present work,
but these do not seem serious enough to discourage from using the methodology.
Validation of simulations—regardless of the type of simulation—cannot be carried out to
objective completeness, but will ultimately rest on faith.
2.3.8 Understanding of factors governing the results of mathematical tools requires familiarity
with governing physical principles, which is an obstacle in many situations. Mathematical
tools can, however, be useful in an auxiliary role.
Table 3: Conclusions drawn from the discussion in Section 2.3.