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2. SITUATIONAL AWARENESS AND COGNITIVE LOCK-UP
 The relationship between situational awareness and capacity of the memory, mental rotation and cognitive lock up
 
 Lt Talma, a former student of the RNLNC, studied the relationship of situational awareness with other phenomena.
 
 The hypotheses were:
・Someone with a bigger memory capacity has a bigger situational awareness.
・Someone with a better ability to mentally rotate has a bigger situational awareness.
・Bigger SA leads to lesser cognitive lock up.
・A better ability to rotate leads to lesser cognitive lock up.
・A bigger memory-capacity leads to lesser cognitive lock up.
 
Fig 12: relationship
 
 During his research he used 4 different tests:
・Episodic memory-test: PC with 3 list with 60 pictures (TNO, 1999)
・mental rotation test: PC.test with 40 trials with 1 picture in the center of the screen and 4 other pictures in the corner; one of the pictures in the corner could be a rotation of the central figure ( TNO, 1999)
・Cognitive lockup test (Space station) (TNO, 2001)
・Bridgesimulator test in the Belgian coast area (BrisimII)
 For his research he joined Ms Aarts in her sessions for Brisim II.
 
Some of the findings:
The first hypothesis: someone with a good ability for mental rotation has a better situational awareness is supported
For the rest of the hypotheses no support was found
 
Some general findings:
 Watch-officers have a better ability in mental rotation than a control group of students, but, as this was not one of the selecting criteria when joining the navy, there is a possibility that this ability is obtained during maritime education. This supports the idea that situational awareness, to a certain degree, is trainable.
 Selection on this subject is (according to the researcher) not necessary.
 
 But on the other hand looking at the figures: watch-officers have a low situational awareness (Happily for them: students even lower). As situational awareness is thought to be essential for watch-officers, further investigation on this subject is to be carried out.
 
3. EXTREME WEATHER CONDITIONS
(A research-program of the CRNAV (combined research navies) together with the NSSWG (naval stability standards working group and the NOGTWG (naval operator guidance and training workgroup))
 
 Since heavy and extreme weather conditions present one of the greatest threats to a ship's strength and stability and since not all those extremes an be avoided, due to the lack of information or other reasons, the ship sometimes is forced into an aspect of her performance that is less than optimal. It is assumed that ocean-going ships have been designed to stay afloat in all conditions. We all know that is not the case. Weather is still identified by the insurers as the single largest cause of losses at sea. One would presume that there would be a fairly well developed body of information available to the mariner on how to best handle a ship in these conditions. Unfortunately, there is very little. Nautical experts therefore advocate the development of such aids like polar diagrams, capsize and broach indices etc. to provide ship operators with the necessary risk management information and ways how to survive.
 Current use of ship simulators typically centers on ship handling in benign conditions and the application of collision avoidance rules. Recent experimentation during a workshop at RNLNC at Den Fielder, with her Full Mission Bridge Simulator equipped to render a serviceable representation of high sea states, demonstrated the worth of using such simulation in exposing ship operators to operational decision making and risk management considerations encountered in marginal sea states.
 Today's ship operator training places greater emphasis in operational risk assessment management, and decision making than has been made in the past. The use of risk assessment tools and risk management schemes allows operators a more robust set of criteria to make go/no-go and how to handle decisions. Environment is a major component in these assessment and management programs. The ability to model significant local wind and wave conditions and their effects on ship models of varying loading conditions with a fairly high degree of fidelity offers a powerful experience for operators under conditions far more forgiving than first-hand knowledge. Such a prototype "heavy weather model" for use on simulators was developed by NSSWG and presented to operators (experienced seafarers with a lot of extreme weather experience) of the NOGTWG for comments.
 During the workshop several scenario's were used. At first a scenario to get acquainted with the M-type frigate, followed by the actual scenario's consisting of following-sea conditions and a head-sea conditions.
 In the design-process of the scenarios, several stability-criteria were taken into account like those of: IMO (A749), US Navy and the Royal Netherlands Navy.
 As the reaction of operators on ships motions was the intention of this investigation, no attention was paid to other important phenomena like bending moments, shearing forces etc.
 
Fig 13: scenario 2a
Simulation Scenario 2a
 
 Maximum loading condition:
 
Fig. 14: condition 2a
Scenario 2a: The Conditions
 
Minimum loading condition:
 
Fig. 15: scenario 2b
Simulation Scenario 2b
 
Fig 16: conditions 2b
Scenario 2b: The Conditions
 
 In the scenarios the waves came from ahead and as the ship was rolling and pitching heavily, participants were forced to find a survival course and speed.
 
Fig.17: overview
Simulation Scenario 2a & 2b
 
In session 3 other test scenarios were presented carried out by the participants like:
・Waves from astern
・All loading conditions
 
in order to study participants on the broaching of the ship and their estimation on capsizing.
 Different initial courses and speeds were presented to investigate the effects
 
Fig. 18: tests scenarios
 
Simulation scenario 3
Modes of Loss of Dynamic Stability
 
・Proceed on heading 90 dgs at 20 knots
・Proceed on heading 105 dgs at 18 knots
・Proceed on heading 105 dgs at 10 knots
 
The scenario as scenario 2b
 
 The purpose of this simulation is to demonstrate several of the modes of loss of dynamic stability in feasible hurricane conditions in a loading condition that is considered to satisfy stability criteria.
 
 The scenario's were tested by experienced seafarers ( commanders) for 3 days and all runs were recorded for further investigation. A small PC-simulator program was provided as an investigation tool.
 All recorded data were available to the participants but as expected they were more interested in the feeling of the rolling and pitching and a way to avoid extremes than the studying of the lists of figures.
 Of course for the naval architects the recorded data were much more of interest. The results of their study are not ready yet, as more "operator studies are needed. Both working groups were pleased to have found each other in this matter of collective interest, actually sailing ships in these extreme conditions, sharing the expectations of what can be expected from ship and human being in those circumstances.







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