: Performance Analysis and Improvement of an Internet Ordering Process The management of a software company wants to study the performance of the companys web order processing. The interarrival times of orders are exponentially distributed with a mean of 7 min. The orders arrive in the form of e-mail. Upon arrival, a clerk looks for the buyers name in the companys database. The time required to look for a name in the Input and Output Data Analysis 405 database is uniformly distributed between 20 and 45 s. If the buyer is not in the database, the clerk enters the buyers information, which includes name, address, phone number, and e-mail address. The time required to enter the buyers information in the database is uniformly distributed between 10 and 30 s. Approximately 60% of the time, the buyers name is not in the database. Some orders are for an upgrade of the software, and the others are from first-time buyers. For all practical purposes, it takes no time to figure whether an order is for an upgrade or from a first-time buyer. Approximately 30% of the orders are for upgrades. If the order is for an upgrade, then the clerk simply enters a code in the electronic purchase order (PO), created when the buyers name was entered or found in the database. (This code is later e-mailed to the customer, so he or she can download an upgrade from the companys website.) Entering the code requires an exponentially distributed time with a mean of 2 min because the clerk needs to verify the customers current software version and platform. After entering the code, the electronic PO goes to accounting. When the order is from a first-time buyer, the clerk checks whether the buyer wants the CD version with printed documentation or whether he or she prefers to download the software from the companys website. This requires an exponentially distributed time with a mean of 1 min because sometimes this information has been misplaced. About 70% of the buyers prefer the CD version. When the CD version is preferred, the clerk needs to retrieve it from the storage room. This activity requires a normally distributed time with a mean of 5 min and a standard deviation of 1. The clerk then prepares the software for shipping, which takes between 3 and 6 min (uniform distribution). If the buyer prefers to download the software, the clerk enters an appropriate code in the electronic PO. Entering the code requires an exponentially distributed time with a mean of 1 min because a computer program sometimes is slow at generating a license for each customer. POs for upgrades and first-time buyers go to accounting after a clerk has either entered a code for downloading or prepared the CD version for shipping. Accounting personnel charge the purchase to a credit card (exponential distribution with a mean of 2 min) and prepare the invoice. Data on invoice preparation times have been collected and are available in Table 9.20. Finally, the accounting personnel mail the software or e-mail the access code with the invoice. This activity requires a uniformly distributed time between 45 and 90 s. Currently, the company employs two people for this process: one clerk for the initial processing and one person in charge of the accounting. However, management is considering adding one person to the process and would like to use simulation to determine where to add this new employee to obtain the maximum customer service benefit.

Questions 1. The first task is to understand this process, and develop a flowchart. This chart should be the first exhibit in your written report.

No. No. No. No. 1 91 2 92 31 32 33 34 3 4 35 5 6 7 8 9 10 11 36 37 38 61 62 63 64 65 66 67 68 69 70 71 72 39 12 40 41 42 43 44 45 73 Preparation 0.987 0.881 1.022 0.799 0.986 1.053 0.493 0.883 1.028 1.057 0.793 1.068 0.836 0.984 1.092 1.006 1.113 0.914 0.877 1.196 1.139 0.937 0.640 1.347 0.961 1.004 1.068 1.170 1.406 1.288 13 14 15 16 Preparation 1.037 1.103 0.965 1.199 0.989 1.055 0.916 0.611 1.044 0.775 0.975 0.699 0.948 1.072 0.929 0.752 1.041 0.878 1.180 1.326 1.064 0.803 1.035 1.073 1.011 1.300 1.333 1.043 0.810 1.141 74 75 Preparation 0.875 0.763 1.283 0.856 1.091 1.028 1.163 0.972 1.082 0.578 0.717 1.473 1.418 1.119 1.102 1.208 0.970 0.757 1.189 1.183 1.300 1.280 1.023 0.852 1.148 0.972 0.747 1.031 1.190 1.017 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 Preparation 0.721 1.132 0.705 1.211 0.831 0.866 1.243 0.431 1.193 1.193 1.220 0.954 1.050 0.747 1.270 0.754 0.807 0.890 0.771 1.099 1.114 0.982 1.235 1.152 0.708 0.745 0.938 1.384 1.033 1.378 46 76 17 47 gRn mm 8 % % %m%%% 18 19 20 21 48 49 50 51 52 53 77 78 79 80 81 82 22 83 54 55 56 23 24 25 26 27 28 29 30 84 85 86 87 57 117 88 58 59 60 89 90 118 119 120 No. No. No. No. 1 91 2 92 31 32 33 34 3 4 35 5 6 7 8 9 10 11 36 37 38 61 62 63 64 65 66 67 68 69 70 71 72 39 12 40 41 42 43 44 45 73 Preparation 0.987 0.881 1.022 0.799 0.986 1.053 0.493 0.883 1.028 1.057 0.793 1.068 0.836 0.984 1.092 1.006 1.113 0.914 0.877 1.196 1.139 0.937 0.640 1.347 0.961 1.004 1.068 1.170 1.406 1.288 13 14 15 16 Preparation 1.037 1.103 0.965 1.199 0.989 1.055 0.916 0.611 1.044 0.775 0.975 0.699 0.948 1.072 0.929 0.752 1.041 0.878 1.180 1.326 1.064 0.803 1.035 1.073 1.011 1.300 1.333 1.043 0.810 1.141 74 75 Preparation 0.875 0.763 1.283 0.856 1.091 1.028 1.163 0.972 1.082 0.578 0.717 1.473 1.418 1.119 1.102 1.208 0.970 0.757 1.189 1.183 1.300 1.280 1.023 0.852 1.148 0.972 0.747 1.031 1.190 1.017 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 Preparation 0.721 1.132 0.705 1.211 0.831 0.866 1.243 0.431 1.193 1.193 1.220 0.954 1.050 0.747 1.270 0.754 0.807 0.890 0.771 1.099 1.114 0.982 1.235 1.152 0.708 0.745 0.938 1.384 1.033 1.378 46 76 17 47 gRn mm 8 % % %m%%% 18 19 20 21 48 49 50 51 52 53 77 78 79 80 81 82 22 83 54 55 56 23 24 25 26 27 28 29 30 84 85 86 87 57 117 88 58 59 60 89 90 118 119 120