BaseOps User's Guide, Chapter 27: Running Cases

After entering all of the data (runways, flight tracks, weather information, etc.) in a BaseOps case, you can run the case: that is, execute the NMap and/or RNM noise models that compute the predicted noise levels. To run the case, select Run Case from the Case menu.

This chapter covers the details of running a case, along with other associated tasks such as checking a case for errors and viewing noise contours using NMPlot.

Checking a Case

To check a case for errors and warnings, you can:

Choose Check Case from the Case menu
Press Ctrl + K

The message report is displayed, showing any errors or warnings found.

Errors must be corrected before the case is run. Warnings do not, but you should carefully consider each one.

To fix errors in the case, click on the hyperlinks included in the message report. These hyperlinks take you to the objects that you must edit to correct the errors.

Tip:

After following a hyperlink, use the back button to easily return to the message report. See Using the Back and Forward Buttons.

At any time, you can go to the message report and view the results of the last error check by choosing Messages from the object type selector dropdown list.

You can print the message report. See Printing Objects.

Setting Grid Properties

The NMap and RNM noise models calculate noise levels at a two-dimensional grid of points covering your area of interest. You can set the grid's location, size, and resolution (distance between adjacent points).

Note:

The grid is always orientated so that its rows and columns run east-west and north-south.

To set the properties of your case's grid, first choose Grid from the object type selector dropdown list. Then set the grid properties in the text pane.

The grid has the following properties.

Location of Center - The location of the center of the grid, specified with respect to the case reference point. Typically, the reference point is located near the center of the area of interest, so the grid location will usually be close to (0, 0).

Note:

The grid location is always specified with respect to the case reference point, regardless of the current case coordinate system.
Point Spacing - The distance between adjacent grid points in the east-west and north-south directions.
Number of Points - The number of grid points in the east-west and north-south directions. The size of the area covered by the grid equals the number of grid points multiplied by the grid point spacing.

Note:

You can select the units used to specify the grid properties. See Setting the Case's Physical Units for more information.

Setting Contour Properties

As the final step in running a case, BaseOps exports each scenario's noise level contours to a file in ARC/INFO Shapefile format. You can then import the contours into a third-party Geographic Information System (GIS). Most GIS's can import shapefiles.

Note:

The NMPlot plotting application can also create contour shapefiles. BaseOps' contour exporting capability is provided as a convenience to those users whose contouring needs are relatively straight-forward. User with more demanding needs should use NMPlot: see Plotting Noise Contours.

To set the properties of the exported contours, first choose Contours from the object type selector dropdown list. Then set the contour properties in the text pane.

The following contour properties can be set.

Contour Levels - Type one or more numbers (separated by commas) specifying the desired noise level(s) of the contours. The contour levels are specified in dB's in the noise metric selected when the case is run: see Noise Metric.
Coordinate System - Select the geographic coordinate system of the contour shapefiles. See Coordinate System Control for more information.

When BaseOps creates a noise contour shapefile, it also creates a metadata file containing information about the shapefile. This metadata file conforms to the Federal Geographic Data Committee's Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998).

Using information drawn from the case, BaseOps can create a reasonable metadata file automatically. However, some users may wish to fine-tune the metadata. Therefore, BaseOps allows you to review the default metadata and, if desired, edit it on an element-by-element basis.

Initially, all metadata elements will have default values assigned to them. For example, the Citation/Title element's default value is the BaseOps case's case name. If you later edit the case name, this element's value will be automatically updated.

You can edit the information displayed in any of the text boxes. When you do, the Reset Element button will be enabled . This indicates that you have overridden the metadata element's default value. Once you have overridden an element's default value, its value is fixed; it will no longer be automatically updated by BaseOps. To restore the element's default value, press the Reset Element button.

Press the Show Element Definition button to display a metadata element's documentation from the FGDC standard.

Note:

BaseOps is not intended to be a general-purpose metadata editor. The FGDC metadata standard defines a large number of elements. The metadata files generated by BaseOps only contain those elements that are expected to be commonly applicable to Noisemap noise contour shapefiles.

Furthermore, BaseOps' Contours page only displays those elements for which there was judged to be a reasonable likelihood that a user would need to override the default value. Elements whose values could be unambiguously calculated (for example, the bounding coordinates) are not displayed on the Contours page, but are included in the metadata file.

Should you have exceptional needs, you can use a third-party metadata editor (or, in its absence, a simple text editor) to fine-tune the generated metadata file. If there are FGDC metadata elements that BaseOps currently does not support, but that you believe are generally applicable to noise contour shapefiles, then contact BaseOps' developers. It may be possible to include those elements in a future version.

Setting Run Options

There are numerous options that affect the computations performed when you run a BaseOps case. To set these options, first choose Run from the object type selector dropdown list. Then set the options in the text pane.

Noise Metric

There are several commonly-used mathematical methods for calculating a single scalar number representing the impact of noise at a location. These are referred to as noise metrics. Select the noise metric that will be calculated when the case is run. You have ten choices.

Name	Description	Supporting Noise Models
CNEL	Community Noise Equivalent Level	NMap, RNM
DNL	Day-Night Average Sound Level	NMap, RNM
LEQ	Equivalent Sound Level (24-hour)	NMap, RNM
NEF	Noise Exposure Forecast	NMap, RNM
WECPNL	Weighted Equivalent Continuous Perceived Noise Level	NMap, RNM

Computations Performed

Each of the noise models supported by BaseOps can calculate noise levels (in the selected metric) at a two-dimensional grid of locations. They can also perform a detailed noise analysis at each of the case's points of interest.

Select whether you would like to perform grid noise computations, points of interest noise computations, or both.

If you choose to perform points of interest computations, a points of interest report will be created. For each point of interest, this report will include a table of the flight and static profiles that contribute the most to the noise level at that point. The NMap and RNM noise models allow you to select the method used to rank the profiles. You have two choices.

Daily - Profiles are ranked by their contribution to the daily noise level.
Event - Profiles are ranked by their single-event noise levels.

Topography and Ground Impedance

When computing noise levels, the NMap and RNM noise models can optionally consider terrain topography and ground impedance. Check the Use topography and ground impedance box, then type the names of the topography and ground impedance files. Press the Browse buttons , located to the right of the text boxes, to display the Open File dialog box, which allows you to browse for the files.

See the NMap documentation for a discussion of the topography and ground impedance files.

Scenarios to Run

Every BaseOps case contains one or more scenarios. See Using Scenarios. When you run a case, a noise analysis is typically performed for each scenario.

You may sometimes wish to run only some of the scenarios in the case. In this situation, select Run Only The Following Scenarios from the dropdown list. A list of the scenarios in the case is displayed.

Check the box next to each scenario that you wish to run. At least one scenario must be checked.

If you are running more than one scenario, select how BaseOps should respond if an error occurs while running a scenario. You have two choices.

immediately halt the run - BaseOps immediately terminates and displays the error message.
attempt to run other scenarios - BaseOps halts the current scenario, but attempts to run any remaining scenarios. After all scenarios are attempted, a summary of the error(s) that occurred is displayed. This is useful if you leave BaseOps unattended (for example, overnight) while running a computationally intensive case.

Steps to Perform

Running a BaseOps case consists of a number of steps (creating the NMap input file, executing the RNM noise model, etc.). Typically, you will want to perform all of the steps. However, there may be situations where you only want to perform some of them. In this situation, select Perform Only The Following Steps from the dropdown list. A list of the steps is displayed.

Check the box next to each step that you wish to perform. At least one step must be checked. The following steps are defined.

Create Omega 10 and 11 Input Files for NMap Operations - Omega10 and Omega11 are the United States Department of Defense's computer programs for extrapolating measured noise data. This step creates input files used to run these programs for NMap operations. The input file names will end in the text NMap - Omega10.i10 and NMap - Omega11.i11. See the NMap documentation for more information.
Run Omega 10 and 11 for NMap Operations - Run the Omega10 and Omega11 programs for NMap operations. The Omega output file names will end in the text NMap - Omega10.o10 and NMap - Omega11.o11, and the Omega log file names will end in the text NMap - Omega10.log and NMap - Omega11.log. See the NMap documentation for more information.
Create NMap OPS File - Create the NMap OPS file. The OPS file name will end in the text NMap.ops. See the NMap documentation for more information.
Create NMap OPX File - Append the Omega 10 and 11 NMap noise profiles to the OPS file to create the NMap OPX input file. The OPX file name will end in the text NMap.opx. See the NMap documentation for more information.
Run NMap - Run the NMap noise model. The NMap grid, point of interest, and log file names will end in the text NMap.grd, NMap.poi, and NMap.log, respectively. See the NMap documentation for more information.

Note:

The grid and point of interest files will only be created if you selected to perform grid and point of interest computations, respectively. See Computations Performed.
Create RNM OPS File - The RNM OPS input file is created. This file's name will end in the text RNM.ops. See the RNM documentation for more information.
Run RNM - Run the RNM noise model. The RNM grid, point of interest, and log file names will end in the text RNM.grd, RNM.poi, and RNM.log, respectively. See the RNM documentation for more information.

Note:

The grid and point of interest files will only be created if you selected to perform grid and point of interest computations, respectively. See Computations Performed.
Create Grid - Create the final noise grid. The output grids from the other noise models are summed, if necessary, and additional grid metadata (description of the Noisemap case and scenario, details of the scenario's flight tracks, points of interest, etc.) is added to the grid.

The final grid will be named casename - scenarioname.grd, where casename is the name of the .baseops case file and scenarioname is the scenario file id name.

To view the final noise grid, choose Plot from the Case menu. See Plotting Noise Contours.
Export Contours - Export noise level contours to a file in ARC/INFO Shapefile format. The shapefile will be written to a file that ends in the text Contours.shp. Shapefile index, shapefile attribute, and FGDC metadata files will also be created; these will end in the text Contours.shx, Contours.dbf, and Contours.xml, respectively. See Setting Contour Properties for more information.

Warning:

If you choose to run only some steps, you are responsible for insuring that the proper steps are run at the proper times. For example, if you run the "Create NMap OPX File" step, then make changes to the case, and then run the "Run NMap" step, NMap will run using the previously created OPX file, which doesn't contain the most recent changes made to the case. BaseOps does not check for mistakes of this kind.

Note:

All of the steps create one or more files. These files will be located in the same directory as the .baseops case file, and will begin with the name of the case file, followed by the scenario file id name. For example, if the case file is named Wright-Patterson.baseops and the scenario file id name is Baseline, then the Omega 10 input file will be named Wright-Patterson - Baseline - Omega10.i10.

Note:

In addition to the OPX file, both NMap and RNM take an additional input file: the RUN file.

BaseOps creates RUN files during the Run NMap and Run RNM steps. However, these RUN files cannot be used to run NMap and RNM directly. This is because BaseOps supports long file names, but the RUN file format only supports DOS-style 8.3 file names. Therefore, when BaseOps runs a case, it must use temporary 8.3 file names for all input and output files. The RUN files BaseOps creates refer to these temporary files.

There are no RUN file options that can't be set using BaseOps. Therefore, as long as NMap and RNM are run from within BaseOps, the fact that the RUN file refers to these temporary files is irrelevant to you. However, if you wish to run NMap or RNM independently of BaseOps, you will need to manually copy all input files to the appropriate temporary files. See the notes at the end of a BaseOps-generated RUN file for more information.

Plotting Noise Contours

After a case has been run, you can use the NMPlot plotting application to display contours of the predicted noise levels. To do so, choose Plot from the Case menu. NMPlot will be started, displaying a contour plot of your case's noise level grid file.

The first time that a grid file is displayed using NMPlot, an NMPlot plot file will be created. This file will have the extension .nmp. If you customize the plot (change the contour levels, add background maps, etc.), the changes will be stored in this file. You can open and edit this file with NMPlot even if BaseOps is not running.

If your case has multiple scenarios, then you will have multiple noise level grid files. In this situation, when you choose Plot from the Case menu, a dialog box will appear, asking you which scenario's grid file you wish to plot.

Select a scenario, then press OK.

Select Contents from NMPlot's Help menu to display the NMPlot User's Guide, which describes NMPlot in detail.