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36 SECTION 5 TOOL DESCRIPTIONS 5.1 OVERVIEW Although these types of questions can be answered using individual management systems, the process is typically time- This section provides a description of each tool that was consuming. Higher level decision-makers currently do not developed and presents requirements that guided the devel- have a convenient way to quickly explore investment trade- opment process. offs across different asset types in a coordinated fashion. User guides, provided on the bound-in CD, were devel- AssetManager NT provides a motivation and a framework oped for AssetManager NT and PT that provide step-by-step for running individual management systems in a consistent, instructions on how to install and use the tools. coordinated way that supports tradeoff analysis. Over time, it may serve as the catalyst for enhancing management sys- tems to produce performance measures that better allow for 5.2 ASSETMANAGER NT comparison of investments across asset types. The overall flow of using AssetManager NT is illustrated Tool Overview in Figure 4. AssetManager NT is a tool to assist transportation agency executives and program managers in understanding how dif- Input Requirements ferent patterns of investment in transportation assets will affect the performance of the system over the long term. The A prerequisite for this tool is one or more functioning man- tool allows a user to explore the implications of different agement systems with the capability to simulate work and to budget levels for a set of investment categories, which can be store simulation results (cost and performance impacts) for defined based on asset types (e.g., pavement versus bridge), different budget scenarios. geographic areas (e.g., districts or regions), or system sub- The current version of the tool is designed to operate with networks (e.g., NHS, trunk line system, priority truck net- results for up to four asset types. However, the design allows work, primary corridors). AssetManager NT brings together for future expansion beyond this number. The tool requires analysis results from the existing management systems in an results from a series of scenario runs at a range of budget agency and adds value by providing a quick-response, what- levels from each management system. Approximately 5 to if analysis tool for testing different investment options. It 10 runs for each investment category to be analyzed are does not replace existing management systems; it builds required to provide sufficient variation in results. upon their capabilities and enables a more integrated (cross- Each scenario run needs to produce the following stovepipe) view of asset investment tradeoffs. information: Some examples of questions to be answered by the tool are: The expenditure level; What happens if we make an across-the-board 30-percent The investment category (e.g., interstate highways in decrease in both pavement and bridge investment levels? District 1); and What happens if we increase funding for the bridge pro- Values of performance indicators associated with the gram by 20 percent and make a corresponding reduction simulation resulting from the scenario run (e.g., per- in the pavement program? centage of network in acceptable condition, depreciated What happens if we spread pavement and bridge fund- asset value). ing evenly across different districts? What would be the resulting impact on remaining life or backlog of work? The tool can use any performance measure produced by a What happens to the condition of nonNational High- management system. The sample data sets provide both asset- way System (NHS) facilities if we focus 75 percent of specific (e.g., pavement condition index) and asset-independent the resources on the NHS? (e.g., user costs, work backlog) examples of measures.

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37 Figure 4. AssetManager NT overview. Companion Robot Tools measures by investment category. Four views are provided for what-if analysis: Two demonstration robot tools--the pre-processor analy- sis routine and the what-if tool--were developed for this The budget view allows the user to explore the relation- project to show how the process of creating inputs for Asset- ship between the average level of investment over time Manager NT can be automated. These robot tools work with and the value of a single performance measure for a the AASHTO Pontis bridge management system and with selected asset and portion of the network. FHWA's HERS/ST tool. Both robots run the management The targeting view allows the user to determine the system (either Pontis or HERS/ST) multiple times and pro- average annual expenditure required to reach a target duce input files that can be read directly by AssetManager performance measure value over a selected timeframe. NT. These tools are described in further detail in the follow- The dashboard view allows the user to look at several ing subsection. different performance indicators at once and to explore their sensitivity to overall budget levels and the alloca- Analysis Capabilities tion of budget across assets, geographic areas, and por- tions of the network. For example, this view could be AssetManager NT is an interpolation engine and visual- used to look at future pavement condition in four dif- ization tool that works with management system results. It ferent regions under different geographic distribution does not include analytic capabilities typically found in assumptions. It also could be used to look at pavement individual asset management systems, such as deterioration condition, bridge condition, and total backlog of work (or modeling, simulation, strategy selection, or optimization. The asset value) for a single district under different assump- software includes two components: a pre-processor of the tions about total budget and allocation of this budget management system run data and a what-if tool. between pavement and bridges. The pre-processor analysis routine is provided to consoli- The allocation view allows the user to define different date information from the various management system runs resource allocation scenarios and to see graphs that into a format that the what-if tool can work with. This rou- compare their performance impacts over time. Like the tine uses an approach similar to that of the FHWA NBIAS, dashboard view, the displays are configurable to show currently in use to analyze national bridge needs. If the pave- several different performance measures or a single per- ment and bridge management systems produce consistent formance measure for different geographic areas or por- performance measures (e.g., monetized user benefits or work tions of the network. backlog or remaining asset value), then the analysis routine can aggregate them. The pre-processor analysis routine prepares a four- Outputs dimensional (i.e., time period, investment category, perfor- mance measures array, and budget level) matrix of results Reports are available for each of the four views described and creates a scenario file that is used by the what-if tool. above. These reports show all of the graphics included in the The what-if tool provides interactive on-screen views of view and are supplemented by information about the sce- the relationship between investment levels and performance nario definition and assumptions underlying the view.

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38 Selection of the Application Platform dated. Definition of functional requirements was a three-step process. First, clear definitions of terminology to be used in The user's primary interface is to a what-if capability from describing the tool were established. Next, business rules were which on-screen views of the relationships between invest- developed that describe fundamental assumptions about how ment levels and performance measures by investment cate- the tool will be used. These rules define what is and is not gory can be explored. This interface needs to be highly inter- allowed for the tool input data and configuration. Finally, the active, to allow the user to directly manipulate various model list of requirements was developed that cover the capabilities parameters and rapidly get feedback in the form of changes to be provided by the tools. These three elements--defini- to charts or graphs depicting the effects of those parameter tions, business rules, and functional requirements--are pre- changes. The fundamental value of this tool is linked to sented in the following subsections for AssetManager NT. its ability to provide a highly interactive graphically based user interface. Therefore, interactive performance is a major requirement: the architecture selected for this tool has to Definitions ensure that the system can query the tool's data set and respond immediately to user interface events. Given the functional Asset Type. A type of asset whose performance is modeled requirements of the tool, a roughly 40 MB source data set to in an individual management system run. support the analysis will need to be kept in memory. Multiuser functionality is not an important requirement for Geographic Category. Categorization of the system accord- the AssetManager NT tool. The tool supports tradeoff analy- ing to a geographically based set of classes (e.g., regions, dis- sis, which by nature is a fairly specialized activity limited to tricts). Categories are assumed to be mutually exclusive and a few key individuals in an agency and/or within each district are assumed to cover the entire system. who will be fully aware of the assumptions and limitations of the tool. The data sets for AssetManager NT are static (i.e., Investment Level. The average annual expenditure within they will not be updated via the tool's interface once they are the defined scope over the scenario time horizon. produced); thus, a capability for multiuser editing is not a requirement and frequent refreshes of the data sets will not be Network Category. Categorization of the system according needed. The data sets will be relatively small (under 50 MB); to non-geographically based attributes (e.g., functional class, thus, these data sets can be duplicated for use on portable ownership, administrative or funding responsibility). Cate- computers (e.g., for presentations to decision-makers). gories are assumed to be mutually exclusive and are assumed Given these requirements, the research team decided to to cover the entire system. implement AssetManager NT as a Windows desktop appli- cation (either on a local or a network drive) that works with Performance Indicator (also referred to as "Indicator"). a binary data set. This approach was selected to provide rapid Raw performance value associated with the given stratifica- interactivity and a rich set of user interface controls, such as tion cell, level of funding, and planning period. sliders. Although development of a thin-client, web-based tool was seriously considered, a web application would not Performance Measure. Performance value obtained as an deliver a satisfactory level of performance (particularly with aggregation of indicators across stratification cells or as a respect to rapid updates to multiple two-dimensional graphs sum or difference of other performance measures. The fol- in response to changes to model parameters). The key advan- lowing aggregation functions will be allowed: SUM, AVG tage provided by a web-based tool--access to a common (weighted average), MIN, and MAX. data set by large numbers of distributed users, thereby elim- inating the need to deploy the application to multiple com- Planning Period. A time period for which individual invest- puters--was not considered important, given the relative ment and performance results are reported in the scenario simplicity of this tool and the anticipated nature of its use. input file (typically 1 year). As a stand-alone desktop application, the tool will have no dependencies on browsers or versions of browsers. Pre-Processor. Piece of analytical software that will process input data in a special way and generate a binary object to be manipulated by what-if analysis. Determination of Functional Requirements Scenario Input File. Data set (file) with information from To guide the tool development process, a set of functional simulation runs obtained from individual asset management requirements were developed. These requirements make up a systems (e.g., Pontis, HERS/ST). checklist of capabilities that the tool should have to be useful and usable. They also define parameters needed by the system Scenario Results File. Binary file generated by the pre- developers, such as the number of asset types to be accommo- processor and used for what-if analysis.

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39 Scenario Time Horizon. The number of planning periods all combinations of the network categories and geo- selected for analysis in the system configuration file and graphic categories that have been defined in the sys- therefore included in the scenario results file. tem configuration. 7. Each simulation run for an asset type must include Simulation Run. An individual simulation run of an asset results for each combination of the network categories management system (or other simulation tool) providing and geographic categories that has been defined in the input data. The tool can accept the results of up to 10 simu- system configuration. lation runs for each asset type. 8. Each simulation run for an asset type must include results for at least two planning periods. Simulation Time Horizon. The number of planning periods 9. Planning periods must be defined consistently across simulated in the simulation runs for individual asset types. asset types; in most cases, these periods will be calen- dar or fiscal years. If they are defined as multiyear peri- Stratification Cell. Combination of asset type, network cate- ods, the definitions of these periods (i.e., start and end gory, and geographic category (e.g., bridges/NHS/District 1). years) must coincide across the different asset types. The tool will limit the number of stratification cells to 480 10. Each simulation run must include expenditures and (4 asset types by 10 network categories by 12 geographic performance measure values for each planning period categories). in the simulation time horizon. 11. Each simulation run for an individual asset type must System. The physical transportation system as defined by the have the same simulation time horizon. set of all assets included in the tool. 12. Simulation runs for different asset types do not need to have the same simulation time horizon, but they do System Metrics File. File containing essential metrics of the need to include some overlap in time. configuration cells (e.g., total deck area of bridges, number 13. The same number of planning periods must be included of bridges, length of the roads) that will be used by the sys- in the scenario time horizon for each asset type. tem as weighting factors for calculation of the performance 14. All expenditure values are to be reported by the source measure averages. management systems in current dollars. 15. The what-if engine will interpolate performance What-If Engine. Interactive user interface and built-in analy- measure results between simulation runs, but it will sis routines to allow a user to conduct asset tradeoff analysis. not extrapolate beyond the highest investment level included for a given scope. If a user enters a higher See Figure 5 for a graphical illustration of the key Asset- investment level for analysis, results from the simula- Manager NT organizing concepts and terms. tion run with the highest investment level will be reported. Business Rules Functional Requirements The following business rules are built into the Asset- Manager NT: Requirement 1. Accept Investment and Performance Data from Asset 1. Results for each asset type are independent of results Management Systems for other asset types. The source management systems are assumed to have already accounted for any double- 1.1 The tool shall accept, in a standard, documented for- counting of costs or benefits or synergistic effects mat, expenditure levels and associated performance that might result from combining work on different indicators generated from simulation runs of asset asset types. management systems. 2. A given performance indicator can apply to one or 1.2 The tool shall allow the user to define multiple sce- more asset types. narios, each representing a different series of man- 3. Each asset type must have one or more associated per- agement system runs. For example, an agency might formance indicators. wish to analyze two scenarios that employ different 4. Each performance indicator may be used for compu- assumptions about changes in future construction costs, tation of one or more performance measures. asset deterioration rates, user cost assumptions, etc. 5. Each performance measure must be associated with a Each scenario will have a user-defined name. single metric defined in the system configuration. 1.3 The following items shall be configurable by the user 6. Values for all metrics defined in the system configu- for each scenario: ration must be included in the system metrics file for Asset types to be included--up to four;

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Scenario Input File (One for each Asset Type) Planning Periods Investment Level 1 Investment Level 2 Simulation Runs Investment Level 10 Geographic Category Network Category Simulation Time Horizon Performance Indicators Preprocessor Create Scenario System Configuration Scenario Input Files Definition of Assets, Network Scenario Time Horizon Categories, Geographic Categories, Planning Periods Metrics, Performance Indicators, and Measures Scenario Input File Asset Type 1 System Metrics File Scenario Input File Asset Type 2 Values of metrics for each Scenario Input File Asset Type 3 combination of Asset, Network Category, and Geographic Category Simulation Time Horizon Scenario Results File pe Pe ime Ty d rio T et ss A Stratification Geographic Category Cells Performance Measures Stratification Cell Investment Level Network Category Figure 5. AssetManager NT: organizing concepts.

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41 Performance indicators to be included in manage- 2.3 The tool shall allow users to set a target value for a ment system results--up to 25 total for all assets; performance measure for the network as a whole at Performance measures (user-defined derivations of the end of a selected time horizon and to see what the performance indicators)--up to 40 total for all annual expenditure level would be required to meet assets; that performance target. Metrics by which weighted averages of performance 2.4 The tool shall allow users to set a target value for a measures are to be calculated; performance measure for a selected portion of the net- Network subset classes to be included--up to 10; work at the end of a selected time horizon and to see Geographic categories to be included--up to 20; what annual expenditure level for that portion of the Number of planning periods (typically years) for network would be required to meet that performance the analysis--up to 20; target. Number of management system simulation runs-- up to 10 per asset type for each scenario; and Scenario name. Requirement 3. Display Results 1.4 Sample system setup input files and results input files in Graphical Views shall be provided with the tool, allowing new users to 3.1 The tool shall provide a budget view that shows (on a run the tool with a demonstration data set prior to single screen) how a selected performance measure preparing data for their agencies. These sample setup changes over time for up to six different annual bud- files will include some standard measures that allow get levels. pavement and bridge investments to be compared. 3.2 The tool shall provide a targeting view that allows a 1.5 A functional prototype robot tool to produce a results user to select a target value for a single performance input file from the Pontis bridge management system measure and see the annual budget level that would be shall be provided with the system. required to achieve that target value. 1.6 A functional prototype robot tool to produce a results 3.3 The tool shall provide a dashboard view that allows a input file for pavement from an HPMS data set (using user to see (on a single screen) how changes in an HERS/ST) shall be provided with the system. annual budget level would affect the values of several 1.7 The system shall allow users to provide baseline val- different performance measures or a single perfor- ues for performance indicators as part of the scenario mance measure for several different portions of the input files. Baseline values are defined as the actual system. This view shall allow the user to specify allo- values of performance indicators for the year prior to cation of resources across assets and, optionally, across the initial scenario year. Baseline values shall not be network and geographic categories. required; the tool shall allow users to designate which 3.4 The tool shall provide an allocation view that allows indicators are to have baseline values. a user to see (on a single screen) how different budget 1.8 The tool shall include the capability to generate and allocations across assets and, optionally, network and store multiple scenarios. Users shall be able to spec- geographic categories would affect the values over ify the scenario name, input file(s) for each asset type, time of several different performance measures or a and number of years of results to extract. single performance measure for several different por- tions of the system. Requirement 2. Provide Capability for Interactive What-If Tradeoff Analysis Requirement 4. Produce Standard Reports 2.1 The tool shall allow a user to see how the values of per- 4.1 The tool shall produce a report that shows the graph formance measures for the network as a whole change in the currently selected view. as a result of changes to (1) total average annual expen- 4.2 The tool shall produce a report that shows the current diture levels, (2) the allocation of resources across scenario settings, including the name of the scenario; asset types, and (3) the allocation of resources across a list of the performance measures, asset types, geo- geographic and network subsets. graphic categories, and network categories; and (where 2.2 The tool shall allow a user to see how the projected applicable) the current allocation of resources across value of a selected performance measure for a selected asset types, network categories, and geographic cate- portion of the network changes given a choice of gories resulting from the user's selections. (1) total average annual expenditure levels, (2) the 4.3 An option shall be provided to save reports to a file for- allocation of resources across asset types, and (3) the mat that allows graphs and tabular information to be allocation of resources across geographic and network imported into Microsoft Office software (e.g., presen- subsets. tations and word processing documents) and modified.