Case Project Simulation Environment
	Case Project Modeled in the Simulation Environment The process modeled in the simulation environment had the following characteristics: · The modeled process included the data capture tasks at a construction site and transfer of these captured data to the field office. · The modeled process involved 11 foremen – responsible for capturing production and resource data for each activity they were liable, 3 project engineers – responsible for processing the production data- and a time keeper – responsible for processing the resource working hours. · Each foreman had a specialty group: drainage, earthwork, structures and roadway. · Each foreman created a time card and on each time card there were 3 activities. · Each activity had a category: planned or unplanned. Planned activity meant the activity was considered during the estimating stage and existed in drawings; whereas unplanned activity meant it was not originally on the plan. Figure 1 shows the overview of the dependency between the agents of this process. Briefly the process works like the following: Figure 1. Overview of Dependency between Agents Once they fill the time cards, foremen transfer the time cards to the responsible project engineer (PE) at the end of the day. Each project engineer processes time cards coming from different groups. Whenever a time card arrives in the office for PE, PE starts processing it. PE’s tasks with the time cards are to look at the production data only for each activity, to calculate the quantity of work done on each day for each activity, and to enter these quantities to the quantity tracking system. While doing this, if there is any missing production data on the time cards, PE contacts to each responsible foreman to get the missing production data. If not provided in this contact, he can do one of the followings: (a) he calculates the quantity of work by looking at the project plans (if the activity on the TC is a planned activity), (b) he goes to the site to make the measurement for the missing quantities observed on all the time cards (if the activity is an additional activity), (c) he makes an estimate if the on-site measurement is not possible any more. When a PE is done with all the time cards, he combines these cards and transfers them to the time keeper. There is only one time keeper at the field office. She gets all the time card batches coming from all of the PEs. For each time card, she checks only the crew and equipment working hours for all the activities. If any of the crew or equipment data is not accurate, she contacts to responsible foreman and corrects these data. Once there is no inaccurate data on a time card, she enters this time card’s working hours to cost accounting system. Simulation Environment  For the purpose of analyzing the model created using the above case study, we implemented a customized simulation environment. In building the simulation environment, we used Discrete Event Simulator (DESim) which is an open-source general-purpose discrete event simulation environment developed in Java Programming Language (information available at http://www.glue.umd.edu/~keceli/web/software/DESim/index.shtml ). It provides the major blocks and functions for building a discrete event system model and measuring user-defined performance metrics. DESim is an event driven simulator as opposed to being time driven and thus, is appropriate in representing the process model for our case. In addition to its built-in features, the input/output interface of DESim is customized and web-enabled for our model Our simulation environment can be accessed from the page: http://www.glue.umd.edu/~keceli/web/software/ITSim/index.shtml. Below screen shot shows the initial page of the simulation environment. The parameters of simulation can be changed by entering values to the related tables that are linked to each button. Each button corresponds to a group of paramters and definitions of those parameters are given below. Click on the buttons in the screen shot to view the parameters and related definitions under each section. Input parameters for the simulation environment 1. Probability of receiving missing production data on a timecard from each foreman group- for planned activities. 2. Probability of receiving missing production data on a time card from each foreman group- for unplanned activities. 3. Durations to collect and enter data by each foreman group. 4. Probabilities for process details (e.g. probability of a given activity to be planned in each group of foreman). 5. Probability of receiving accurate crew/equipment working hrs data on a timecard from each foreman group- for planned activities. 6. Probability of receiving accurate crew/equipment working hrs data on a time card from each foreman group- for unplanned activities. 7. Durations to do tasks by the data processing agents. 8. Durations of contacts for data processing and collection agents to complete missing data / to correct inaccurate data. 9. User selection for the process model (base case; laser scanner implemented case; RFID implemented case).
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