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H A R D WA R E R E Q U I R E M E N T S A N D R U N N I N G T I M E 183 TABLE 1 2000 and 2030 Running Times of the MORPC Travel Models (Hour:Min) 2000 2030 MORP C 3 MORP C 4 COTA MORP C 3 MORP C 4 COTA Households 610,774 610,774 610,774 872,919 872,919 872,919 Population 1,435,389 1,435,389 1,435,389 1,956,660 1,956,660 1,956,660 Tours 2,074,618 2,073,659 2,075,797 2,997,507 2,997,214 2,996,117 Core model total (3 iterations) 35:43 31:20 20:55 48:35 41:23 26:43 Iteration 1 11:27 10:08 6:51 16:18 13:28 8:30 Iteration 2 11:26 9:55 6:28 14:59 12:48 8:06 Iteration 3 12:49 11:16 7:36 17:17 15:06 10:06 Iter 1 - Population synthesis 0:02 0:02 0:01 0:02 0:02 0:01 Iter 1 - Sending files to workers 0:20 0:20 0:12 0:19 0:20 0:14 Iter 1 - Auto ownership 0:01 0:01 0:00 0:02 0:02 0:01 Iter 1 - Mandatory tour generation 0:53 0:53 0:39 1:15 1:15 0:39 Iter 1 - Mandatory DTM 4:01 3:14 1:59 6:07 4:48 2:50 Iter 1 - Joint tour generation 0:12 0:12 0:08 0:14 0:14 0:08 Iter 1 - Joint tour DTM 0:08 0:06 0:04 0:08 0:07 0:05 Iter 1 - Individual tour generation 0:05 0:05 0:05 0:07 0:07 0:05 Iter 1 Individual tour DTM 0:54 0:41 0:23 1:15 0:56 0:30 Iter 1 - At-work subtour DTM 0:08 0:07 0:06 0:12 0:10 0:07 Iter 1 - Mandatory stops model 0:49 0:38 0:21 1:14 0:59 0:32 Iter 1 - Joint stops model 0:07 0:06 0:04 0:08 0:07 0:05 Iter 1 - Individual stops model 0:54 0:43 0:24 1:11 0:54 0:31 Iter 1 - At-work stops model 0:06 0:05 0:04 0:09 0:08 0:05 Iter 1 - Writing files and trip tables 0:13 0:13 0:10 0:35 0:34 0:26 Iter 1 - External model + 0:00 0:00 0:00 0:01 0:01 0:01 Iter 1 - Commercial vehicles + 0:02 0:02 0:01 0:02 0:02 0:01 Iter 1 - IE trips + 0:00 0:00 0:00 0:00 0:00 0:00 Iter 1 - Highway assignment - 2 period + 1:08 1:14 1:07 2:03 1:31 1:16 Iter 1 - Highway and transit network skimming + 1:17 1:17 0:53 1:04 1:03 0:44 Iter 3 - Highway assignment - 4 period + 2:14 2:18 1:51 3:11 3:07 2:19 Iter 3 - Transit assignment - 2 period + 0:16 0:16 0:10 0:12 0:12 0:07 Times for the individual model components are sending TP+ scripts to run in parallel. This is not possible shown for Iteration 1. At the end of Iterations 1 and 2, on the MORPC system as the workers are running Linux. the a.m. and midday highway trips are assigned and the congested networks are then skimmed for feedback to the next iteration. Afternoon and night skims are the MORPC MODELING STAFF transposed a.m. and midday skims. At the end of the third iteration, all highway and transit trips are assigned MORPC employs three staff members who use the travel to the appropriate network. forecasting model directly. Responsibilities are broken As seen from Table 1, 2030 takes longer to run than down roughly as follows: 2000 due to the additional population and tours. The addition of the fourth worker on the MORPC system Senior Engineer: This person manages the model improves the running time on the DTM and Stops mod- development and is familiar with the theory behind the els. The COTA system shows the most significant model. This person runs the model for projects when improvement in running times due to 64-bit computing needed and would proffer new features to be added to and runs substantially faster than the 32-bit MORPC the model. This job includes model validation and cali- system. Therefore, any future installations of the bration and script writing in support thereof. MORPC model system would almost certainly involve Associate Engineers (2): These people run the 64-bit computing. model for project-level analysis and air quality confor- All run times are based on Cube Version 3.2. All TP+ mity. They maintain and upgrade the highway and tran- programs are run on the server in sequential order. It has sit networks. been found that Windows will only allocate a maximum of 50% of its CPU power to any one application. There- In addition to the staff above, MORPC employs five fore, if the TP+ scripts were run in parallel, a significant staff members who maintain and forecast the socio- time savings could result. Future upgrades include conomic variables and two others who use the model installing Cube on the systems of the COTA workers and results.