Requerimientos del sistema

For the determination of the number of measurements that had to be done in order to create data that are statistically correct, the formula of Pollux has been used.

𝑛 =4𝑝 (100 − 𝑝) (2𝑠)^2

Hereby is n the sample size, p the estimated time-percentage spent and s the accuracy of the measurement.

For every activity per work cell, firstly an estimation was made about the percentage of the time that is spent. In alignment with KCS, an accuracy of 15% was used for each measurement, as it is a global indication of the time spent on each activity. Filling in the estimated time- percentage and the accuracy led to a certain number of measurements. As can be seen from the tables below, the maximum amount of measurements that was indicated is 11. Therefore, for each activity 11 measurements will be done, in order to analyze the data statistically correct.

Table IV-1 - Measurements C-class MND

Activity Estimated time (%) Accuracy #Measurements necessary Start/stop 1 Retrieve set-up C-

trolleys from storage area and put them on the lifting table. Also gather oven racks for special meals.

15% 0,15 5,67 Start: when leaving

lifting table. Stop: back at lifting table

2 Fill the trolleys with equipment according to the specified loading diagram

20% 0,15 7,11 Start: when first tray is

stowed.

Stop: when last tray has been stowed.

3 Retrieve totes with C- class main dishes from cooling

5% 0,15 2,11 Start: when leaving

lifting table. Stop: back at lifting table

4 Stow main dishes in trolleys

45% 0,15 11,00 Start: when first meal is

stowed.

Stop: when last meal is stowed.

5 Scan production card bar codes to notify the trolleys are complete

5% 0,15 2,11 Start: when scanner is

picked up.

Stop: when last card has been scanned.

6 Push completed trolleys to the distribution gates

10% 0,15 4,00 Start: when lifting table

goes down.

End: when coming back to lifting table.

107

Table IV-2 - Measurement C-class juice & HSN

Activity Estimated time (%) Accuracy # Measurements necessary Start/stop 1 Retrieve set-up C- trolleys from storage area and put them on the lifting table. Gather oven racks for special meals.

15% 0,15 5,67 Start: when leaving lifting

table.

Stop: back at lifting table

2 Retrieve totes with C-class juices & hot snacks from cooling

10% 0,15 4,00 Start: when leaving lifting

table.

Stop: back at lifting table

3 Stow juices and crackers in the juice trolleys. Stow hot snacks and the required number of PSU plates in the hot snack trolleys.

45% 0,15 11,00 Start: when first meal is

stowed.

End: when last meal is stowed.

4 Scan production card bar codes to notify the trolleys are complete

10% 0,15 4,00 Start: when scanner is

picked up.

End: when last card has been scanned.

5 Push completed trolleys to the distribution gates

15% 0,15 5,67 Start: when lifting table goes

down.

End: when coming back to lifting table.

108

Table IV-3 - Measurements M-class MND & HSN

Activity Estimated time (%) Accuracy # Measurements necessary Start/stop 1 Retrieve set-up M-trolleys from storage area and put them on the lifting table. Gather oven racks for special meals.

15% 0,15 5,67 Start: when leaving lifting

table.

Stop: back at lifting table

2 Retrieve totes with M-class main dishes & hot snacks from cooling

10% 0,15 4,00 Start: when leaving lifting

table.

Stop: back at lifting table

3 Stow main dishes and hot snacks in trolleys

45% 0,15 11,00 Start: when first meal is

stowed.

End: when last meal is stowed.

4 Scan production card bar codes to notify the trolleys are complete

10% 0,15 4,00 Start: when scanner is

picked up.

End: when last card has been scanned.

5 Push completed trolleys to the distribution gates

15% 0,15 5,67 Start: when lifting table goes

down.

End: when coming back to lifting table.

109

Table IV-4 - Measurements CTR

Activity Estimated time (%) Accuracy # Measurements necessary Start/stop 1 Retrieve set-up CTR-trolleys from storage area

20% 0,15 7,11 Start: when leaving lifting

table. Stop: back at lifting table

2 Retrieve ice- cream cups from cooling and totes with rolls from GOC.

15% 0,15 5,67 Start: when leaving lifting

table. Stop: back at lifting table

3 Stow rolls and boxes in the containers

40% 0,15 10,67 Start: when first meal is

stowed. End: when last meal is stowed.

4 Scan production card bar codes to notify the trolleys are complete

10% 0,15 4,00 Start: when scanner is

picked up. End: when last card has been scanned.

5 Push completed trolleys to the distribution gates

15% 0,15 5,67 Start: when lifting table goes

down. End: when coming back to lifting table.

110

Table IV-5 - Measurements Silverware

Activity Estimated time (%) Accuracy # Measurements necessary Start/stop 1 Retrieve set-up CTR-trolleys from storage area

15% 0,15 5,67 Start: when leaving lifting

table. Stop: back at lifting table

2 Build bread basket and serving tray supply

15% 0,15 5,67 Start: when building first

basket. End: when last one is built.

3 Set-up containers with the built-up supply according to production card. Stow other items from totes in container.

30% 0,15 9,33 Start: when first meal is

stowed. End: when last meal is stowed.

4 Scan production card bar codes to notify the trolleys are complete

10% 0,15 4,00 Start: when scanner is

picked up. End: when last card has been scanned.

5 Push completed trolleys to the distribution gates

15% 0,15 5,67 Start: when lifting table goes

down. End: when coming back to lifting table.

111