Thad C. Pratt And Daryl S. Cook
US Army Corps of Engineers Engineering Research and Development Center
3909 Halls Ferry Rd., Vicksburg, Ms. USA 39180
(601) 634-2959 Phone ,(601) 634-3694 Fax
E-mail Prattt@wes.army.mil
Abstract: Modern electronic instrumentation produces large amounts of
data. Often, this abundance of data is not fully utilized because the engineer
or scientist does not have an effective way to visualize and analyze it within a
projects time schedule. This problem can be minimized by a set of tools that
provides ready capability to visualize, analyze, reduce, and efficiently plot
data obtained from such instrumentation. Additionally, such a tool can take
advantage of geographically referenced data of high spatial accuracy. HyPAS is
designed to be a Geographic Information System (GIS) for hydraulic data, capable
of managing, storing, manipulating, and displaying geographically referenced
data. A mapping system alone lacks database management capabilities. GIS
software provides both applications with a robust set of tools capable of
manipulating large amounts of data with high spatial accuracy; however,
typically a substantial learning investment is required to become proficient
with GIS software. HyPAS is designed to lessen the learning curve and provide
analysis tools to facilitate processing field data.
Keywords: ADCP, acoustic doppler current profiler, grain size data,
sediment samples, gis, geographical information system, hypas, hydraulic process
analysis system
1 INTRODUCTION
HyPAS builds on the inherent power of GIS while supplying easier tools for
facilitation of hydraulic process analysis and reducing learning time typical
with GIS implementation. HyPAS is an extension to ArcView, a commercially
available software package marketed by Environmental Systems Research Institute
(ESRI), and requires an additional extension from ESRI, 3D Analyst. HyPAS was
designed for the non-GIS expert with ease of use as a priority. A detailed
presentation of instructions for using HyPAS can be found in the HyPAS User’s
Manual (Pratt and Cook 1999). The HyPAS was designed to perform all major
functions after collection of data to report writing. The system supports
hydraulic and hydrodynamic studies involving:
l Velocity
Ø Plan View Contours
Ø Plan View Vector Plots
Ø Cross-Section Plots
l Sediment Samples
Ø Grain-Size Distribution Plots
u Frequency Weight Histogram
u Cumulative Frequency Weight Percent
Ø Composite Sample From Multiple Samples
Ø Comparing Composites with Reference Curves
u Adjust Fill Factor (RA)
u Renourishment Factor (RJ)
l Project Management
Ø Importing Photographs
Ø Time Series Data Analysis
l New tools are constantly under development to meet project needs.
HyPAS’s velocity analysis tools cover three basic applications: contouring an
area in plan view from a user-defined constituent and depth range, generating
cross sections from a transect, and plotting vector magnitude and direction in
plan view from a user-specified depth range.
HyPAS’s sediment sample analysis tools allow the user to generate frequency
weight plots, calculate composite sample plots, and perform varied analysis
routines. HyPAS’s project management tools allow the user to import
photographs for project enhancement and import time series data to manage and
plot.
2 GENERATING PLAN VIEW CONTOURS
HyPAS provides the capability of generating contours in plan view for the different constituents collected from the Acoustic Doppler Current Profiler (ADCP) instrument. HyPAS will create color-shaded contours and contour lines. This tool allows the user to calculate the depth average of the specific values from the entire water column or a specific depth range. The user selects the survey data to contour by drawing a box or polygon around them. A depth range is specified, and the user must choose which constituent to contour. HyPAS then calculates the contour from the depth range specified. An example plan view contour of total velocity magnitude was created from ADCP data in the Columbia River, Oregon (Figure 1). The yellow dots represent actual velocity profiles collected by the ADCP as the boat moves along the line. The legend for the color-shaded contours represents velocity magnitude in ft/sec. The units for velocity magnitude depend on how the data were processed. Often, velocity magnitude is represented in cm/sec.
Fig. 1 Plan view contour of the total velocity magnitude from an ADCP survey inthe Columbia River
3 GENERATING PLAN VIEW VECTOR
HyPAS provides the capability of generating a vector plot of magnitude and
direction in plan view for the velocity data collected from the Acoustic Doppler
Current Profiler (ADCP) instrument. HyPAS will create a plot with vectors
pointing in the direction of flow and scaled in size by magnitude. This tool
allows the user to calculate the depth average of velocity magnitude and
direction from the entire water column or from a specific depth range. The user
selects the survey data points to plot by drawing a polygon around them. A depth
range is specified. HyPAS then calculates and plots the depth-averaged magnitude
and direction for those survey points. Figure 2 is an example of depth averaged
velocity magnitude and direction vectors from ADCP data at Shinnecock Inlet, New
York.
Fig. 2 Plan view velocity magnitude and direction plot from Shinnecock Inlet, New York (flood current)
4 GENERATING CROSS SECTIONS
HyPAS provides the capability of generating a cross section from a specific transect or points along multiple transects from velocity survey data. This tool allows the user to calculate a cross section from any constituent in the data. This includes the north, east, and vertical components of velocity as well as acoustic backscatter. The user selects the survey data points by drawing a polygon around the individual points and selecting a starting point. The constituent to contour is selected. HyPAS then interpolates and plots the cross section. A cross section was created from ADCP data collected from an area called Victoria Bend in the Mississippi River (Figure 3).
Fig. 3 Cross section of Victoria Bend in the MS River
5 IMPORTING AND DISPLAYING IMAGES
HyPAS provides the capability of importing and displaying digital photographs
and images to enhance project management. This tool is not designed for image
processing, but rather as an end product aid for representing analysis results
and methods. This tool allows the user to import digital photographs and images
and attach them to specific spatial locations throughout the study area. The
images are stored using a separate image theme as shown in Figure 4. On the
image theme, a small solid filled circle with an “i” denotes the locations
of the images. Presently, a maximum of ten digital images can be stored at each
spatial location. This tool is useful for recording conditions at a site or
progress of a construction site. Images allow the user the opportunity to store
and display instruments, flow conditions, historic photos, and other visual
information quickly and easily for reference. Once the user has imported the
photography, it is displayed by clicking on the spatial location to which it was
linked. Several photographs were added to a GIS project for Shinnecock Inlet,
New York. Two photographs are displayed showing the inlet at previous times in
its history (Figure 4).
Fig. 4 Shinnecock Inlet GIS project utilizing HyPAS tools for displaying photographs
6 TIME SERIES ANALYSIS
HyPAS provides capabilities for importing, storing, analyzing, and exporting
time-series data. This is a project management tool that allows the user to have
time-series data flags throughout his project. The user can click to create a
location for time-series data and import the data for that location. Later the
user can choose that location and HyPAS will display all the data types, which
have been imported. HyPAS will plot the data on an X, Y plane using the plot and
axis information given by the user. HyPAS automatically exaggerates the Y axis
to fit an 8.5 x 11 landscape plot. Figure 5 shows a time-series plot of wind
speed information.
Fig. 5 Maximum wind speed time-series data plot
7 SEDIMENT SAMPLE ANALYSIS TOOLBOX
HyPAS provides capabilities for analyzing sediment samples and similar data. The
user can plot cumulative frequency weight percent or frequency weight percent
histograms. HyPAS keeps these plots linked with the data in plan view as well as
tabular view. The user can then select certain samples in the plot and see those
specific samples highlighted in plan and tabular views. This linkage works in
all three views such that any selections including tabular queries are reflected
in the other two views. The user can select samples in any of the windows, and
the other two windows will show the selection. Figure 6 shows the linkage
between a frequency weight histogram plot with the plan view and tabular data
view. Note the selected (red colored) samples in all three views.
Fig. 6 View showing link between distribution plots and plan view data
8 PLOTTING GRAIN SIZE DISTRIBUTION
HyPAS provides the capability of plotting grain-size distribution for sediment
sample data. The user can plot cumulative frequency weight or frequency weight
percent histograms. HyPAS can plot all samples selected or calculate a composite
for the selected samples. The user has the option of sorting the tabular data
before making a selection of samples for display in the plotting window. Once
sediment samples are imported, the user must select the samples desired for a
grain-size distribution plot before selecting the Sediment Sample Tool. The
option to plot the cumulative frequency weight percents, the frequency weight
percent histogram, or a composite sample plot is provided. HyPAS then generates
the distribution plot. Figure 7 shows frequency weight percent histograms with a
composite histogram from a subset of sediment samples collected from the
Shinnecock Inlet.
Fig. 7 Example of a Series of Sediment Samples
and Composite Sample. The first plotdisplays the Frequency Weight Percent
Histograms, and the second plot displays the Cumulative Weight Percent
A cumulative frequency weight percent plot of the same sample is also shown. The
thicker line delineates the composite sample. Various statistical parameters
describing this composite sample are stored to a table. These statistics include
the median, other percentiles, the Fill Factor (RA ), and the Renourishment
Factors (RJ). Different composites can then be easily compared. See Hands and
Chu (1986), ftp://redarrow.cerc.wes.army.mil/ftp/pub/pub/pdf/cetnii-15.pdf, for
a discussion of the RA and RJ. The broader aspects of coastal sediments,
including their composition and fall velocity, are discussed by King (1999), http://www.usace.army.mil/inet/usace-docs/eng-circulars/ec1110-2-292/c-1.pdf.
9 EXTENSION INFORMATION
HyPAS is an extension to ArcView 3.1. It enhances or automates some features already present in ArcView’s Graphical User Interface (GUI), and it extends the current capabilities of ArcView 3.1. All of functionality of ArcView 3.1 and Spatial Analyst extension is still available to the user along with HyPAS capabilities. This affords access to the power of ArcView GIS and HyPAS. The user could create a hillshade of bathymetry in ArcView and Spatial Analyst; then overlay vector magnitude and direction plot using HyPAS to produce even more useful output. (Figures 8 and 9) SHOALS (http://shoals.sam.usace.army.mil) data have also been imported to create contoured plan view plots and hillshade applications.
Fig. 8 Hillshade of high resolution multi-beam bathymetry, Victoria Bend, Mississippi River
Fig. 9 Bathymetric hillshade with vector magnitude and direction overlaid, Victoria Bend, Mississippi River
References
Hands, E. B., and Chu, Y. (1986), “Overfill and Renourishment Factors,”
Coastal Engineering Technical Note CETN-II-15, U.S. Army Engineer Waterways
Experiment Station, Coastal Engineering Research Center, Vicksburg, MS, http://bigfoot.wes.army.mil/cetn.index.html.
King, D. B., Jr. (1998) “Coastal Sediment Properties,” in the Coastal
Engineering Manual, Part III-1, EC 1110-2-292, U.S. Army Corps of Engineers,
Washington, DC.
Pratt, T. C., and Cook, D. S. (In press). “HyPAS User’s Manual: A Hydraulic
Processes Analysis System,” U.S. Army Engineer Research and Development
Center, Coastal and Hydraulics Laboratory, Vicksburg, MS.