## 5 Results
### Bridge Navigation Items Related to Required Information for SA (Q1 in Table 2)

Table 6: Linkage between required information for Level 1 SA and ship sense. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{2}{c}{**Required Information**} & \multirow{2}{*}{**Ship Sense (Visibility)**} & \multicolumn{2}{c}{**Ship Sense (Others)**} \\ \hline
18 & Moisture & & ✓ &
\begin{tabular}{c} * Thermal sense \\ (Humidity) \\ \end{tabular} \\ \hline
19 & Amount of cloud & ✓ & * Scenery outside the bridge & \\ \hline
20 & Sky condition & ✓ & * Scenery outside the bridge & ✓ & * Thermal sense \\ \hline
21 & Speed of wind (relative & ✓ & * Wave motion & ✓ & * Body sense (wind) \\  & and absolute) & ✓ & * Wave motion & ✓ & * Sound \\ \hline
22 & Direction of wind (relative and absolute) & ✓ & * Wave motion & ✓ & * Body sense (wind) \\ \hline
23 & Speed of tidal current & ✓ & * Sailing wave and sea wave & & \\  & & ✓ & * Form on the sea surface and & & \\  & & ✓ & floating object & & \\  & & & * Lean of a buoy & & \\ \hline
24 & Direction of tidal current & ✓ & * Sailing wave and sea wave & & \\  & & ✓ & * Form on the sea surface and & & \\  & current & & floating object & & \\  & & & * Lean of a buoy & & \\ \hline
25 & Direction of Wave (wind, swell) & ✓ & * Wave motion & ✓ & * Body balance (Labouring of a ship) \\ \hline
26 & Height of Wave (wind, swell) & ✓ & * Wave motion & ✓ & * Body balance (Labouring of a ship) \\ \hline
27 & Target location & ✓ & * Appearance of target ships & ✓ & * Sound (Whistle, Engine of target ships) \\ \hline
28 & Target speed & ✓ & * Movement of target ships & & \\  & & ✓ & * Ship wave & \\  & & ✓ & * Change of course of target & & \\  & & & ships & \\ \hline
29 & Target distance & ✓ & * Appearance of target ships & & \\ \hline
30 & Target course & ✓ & * Appearance of target ships & & \\  & & ✓ & (e.g., bow direction) & & \\ \hline
31 & Target bearing & ✓ & * Change of course of target & & \\  & & ✓ & ships & \\  & & ✓ & * Appearance of target ships & & \\ \hline
32 & Number of targets & ✓ & * Appearance of target ships & & \\ \hline
33 & TSS to be followed & ✓ & * Location of the object of land & & \\  & & or sea & & \\ \hline
34 &
\begin{tabular}{c} VTS communication \\ frequency \\ \end{tabular} & & & & & \\ \hline
35 &
\begin{tabular}{c} VTS standing \\ instructions \\ \end{tabular} & & & & & \\ \hline
36 & Location of navigation & & * Location of land object & & \\  & hazards & ✓ & (confirmation of the distance & & * Smell (Salty air) \\  & hazards) & & & \\ \hline
37 & Anchorage areas & ✓ & * Location of land object & & \\  & & (confirmation of the distance & & \\  & & & between a ship and anchorage & & \\  & & areas) & & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: _Cont._Lack of Ship Sense and Required Information for SA of RO (G3 and G4 in Section 4.1 and Q4 and Q5 in Table 2)  
As described in Section 3.3, the required information for SA of RO has a shortage due to the constraint of transmission of the information on environment inside/outside the bridge of a ship to RCC. The experts discussed in the mini focus group how they rate each item of ship sense and required information based on the results of G1 and G2 and the interview, and agreed upon them. Table 7 is the matrix of lack of ship sense and lack of required information for Level 1 SA. Each lack was rated on a three-point scale (A-large, B-middle and C-low for ship sense, and 1-critical, 2-middle and 3-low for required information for Level 1 SA). The category of 'lack of ship sense' indicates the sensitivity of ship sense against the restriction of the data transfer. For example, if RO can easily feel ship sense even by rough visual screen, the lack is small. The results show that ship sense is failed at least at the middle level (B-middle); i.e., participants feel that the restriction of data transmission affects ship sense at a high level. The lack of required information indicates the need of ship sense in the total information resources to acquire the required information. VTS-related information is removed from this matrix since these items do not connect ship sense (see Table 6).