Ratiordiregion  Ratio for a region and a representative day i (for each day of the six weeks of collected data). 
NFrdi AERO2K  Number of flights calculated from AERO2K merged inventory for a representative day i. 
NFrdi BA  Number of flights calculated from Back Aviation database for a representative day i. 

Asia and Pacific = NF20020206 BA
Example: Ratio20020206 AERO2K / NF20020206

Once all ratios are calculated, the appropriate ratio must be applied to the virtual day that needs to be created. For this, the representative days were classified into seasons as shown in Table 46. A virtual day chosen as Wednesday 9th of January 2002 is related to the ratio matching the season and the day i.e. Wednesday 6th of February 2002. The day selected is the closest day with the same day of the week.
Table 46: Listing of the representative days in 2002 and classified in seasons.

2002  February  April  June  September  October  Decembe r 
Monday  4  8  10  9  7  2 
Tuesday  5  9  11  10  8  3 
Wednesday  6  10  12  11  9  4 
Thursday  7  11  13  12  10  5 
Friday  8  12  14  13  11  6 
Saturday  9  13  15  14  12  7 
Sunday  10  14  16  15  13  8 
Season  Winter  Spring  Spring  Summer  Autumn  Autumn 
From/to  21/12 to 20/03  21/03 5/05  to  6/05 to 20/06  21/06 to 20/09  20/09 to 25/11.  25/11 to 20/12. 

From the files extracted from Back Aviation database, the number of flights for the selected virtual day and region is retrieved. This number of flights is multiplied by the matching ratio, which gives the number of flights calculated for the selected virtual day.
recAERO2K = Ratiordiregion x NFvdiBANFvdi

NFvdi recAERO2K  Number of flights recalculated for the virtual day i chosen. 
Ratiordiregion  Ratio calculated for the representative day i in a region and selected as the best match for the region and the virtual day i chosen. 
NFvdi BA  Number of flights obtained from Back Aviation database for the chosen virtual day i. 

recAERO2K = Ratio20020206 Asia and Pacific x NF20020109 BA
Example: NF20020109 At this stage, only a number of flights (NFvdirecAERO2K) is calculated for the chosen virtual day; the difficulty is in generating flights between city-pairs. The retained approach consists of selecting the inventory for the representative day associated to the virtual day chosen and to adjust the number of flights (NFrdiAERO2K) to the number of flights calculated
recAERO2K).
(NFvdi
If flights need to be deleted, for each airport in a region, the number of flights for the representative day is counted (A). The region ratio previously calculated is then applied to the number of flights for the representative day, which gives the number of flights to delete (B). In the virtual day inventory, every A out of B flights is deleted.
If flights need to be inserted, for each airport in a region, the number of flights for the representative day is counted (A). The region ratio previously calculated is then applied to the number of flights for the representative day, which gives the number of flights to insert (B). A list of all inventory flights ordered by the time of day from the airport considered is extracted from the representive week inventory. It gives a pick list of possible flights to copy (C). In the virtual day inventory, every C out of B flights is inserted to the virtual day inventory.
The overall method is applied to the seven regions and the regional inventories are combined into a final world inventory for the virtual day chosen.
　
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本文鏈接地址：AERO2K Flight Movement Inventory Project Report(39)