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51 This chapter discusses the data management tools and tech- niques for managing geospatial data acquired by transporta- tion agencies. This is becoming increasingly important for personnel in a variety of divisions. Managing this resource effectively requires appropriate platforms and careful plan- ning. Once acquired, software to process, analyze, visualize, share, manage, and maintain these data is needed. Several software suites can be necessary to support this critical need. Singh (2008) presents a vision for data management within the Oregon DOT. Data are centrally stored and updated so that current information is available to all divisions. Singh discusses various technologies that make this feasible. Singh also argues that the most thorough survey for an infrastructure project should be performed after the project is completed to record as-built conditions, rather than before the project, as is traditionally done. Then, any modification/maintenance/ update would be documented geo spatially in the central data- base to keep it current. Geospatial data can be used for multiple applications; therefore, storing it in its original form will allow integra- tion into all applicable uses. Two major methods of storing roadway data used by transportation agencies are LRS and GIS. LRS is a more historical method that is well established in some agencies. GIS is a newer, more advanced technol- ogy that is in various stages of implementation in numerous agencies and being explored by several others. Comparisons of these two structures are presented in Table 23, and more complete definitions are in the following sections. GEOGRAPHICAL INFORMATION SYSTEM GISs store and manage geospatial databases as vector fea- tures (polygons, points, polylines, and so forth) or raster grids, tying feature attributes to geospatial positioning infor- mation. Once data are integrated into a GIS platform, attri- butes can be associated, allowing an infinite number of layers to be created, analyzed, and output to end users. These users can also employ technologies such as online mapping ser- vices and CAD to promote interactive, useable maps. GISs are becoming essential tools for city and state municipalities. Many of these organizations have detailed standard operating procedures and best practices to support information dissem- ination. It is beneficial for these organizations to continually look for ways to improve the operability of their data man- agement system. GIS and CAD have evolved independently over the last few decades. Both systems have several similarities and key differences. Both CAD and GIS support multiple layers to organize and view data. However, the focus of GIS is map- ping features and their attributes to geospatial locations with database integration, whereas CAD focuses on the graphical presentation of drawings for designs. Both support imag- ery for base maps. GIS provides advanced coordinate sys- tem support and projection on the fly; although some CAD packages are integrating this support. Geometric data can be transferred from CAD to GIS and vice versa; however, traditional CAD software does not provide database support for attribute information. Newer, parametric CAD software, such as BIM platforms, enable attributes to be stored with line work. GIS offers much of the functionality available in CAD for line work and mapping; however, GIS provides many more spatial analysis tools. Although some highway design can be done in GIS, most design is done in CAD packages because of lower software costs, a design-focused interface, and familiarity of personnel who are already trained in using CAD. Further, design of a complicated structure such as a bridge, for example, is simpler using tools available in CAD. A research report investigating current trends and forecast- ing future market development of global GIS for transporta- tion projects was published recently (âGlobal . . .â 2012). The analysts forecast that this market will grow at a rate of 12.5% from 2011 to 2015. The report also highlights the introduc- tion of 3D virtual navigation in GIS. This report includes an analysis of and observations from several leading geospatial service providers on future opportunities and growth. Finally, the report discusses the impact of government regulations. LINEAR REFERENCING SYSTEM LRS is a location system based on linear dimensions fol- lowing the centerline of the road or railway from a predeter- mined point, such as the start of a highway. An LRS allows one to quantify and qualify resources based on their spatial location. Higher-accuracy GPS mapping of road centerlines aids manual cartography efforts in LRS creation. An LRS can be an intuitive system for maintenance crews and the traveling public. LRSs generally do not require spe- cial equipment for location information because the locations chapter six DATA MANAGEMENT AND SOFTWARE
52 can be approximately derived by mile markers posted along the highway. In addition, they have commonly been used with emergency response systems. However, LRS does not provide the same level of accuracy and navigability in 3D space as does GIS. Further, LRS coordinates require additional software to be derived from GPS coordinates. NCHRP Report 460 sets standardization methods for LRS. The researchers distributed a state-of-the-practice question- naire to draw out some common inferences that create a âconsensus-based, functional requirementâ approach to stan- dardization. âA comprehensive data model and implemen- tation guidelineâ for this model were final products of the project (Adams et al. 2001). Multilevel LRS is an enhancement to traditional LRS that increases functionality but has not been implemented by many transportation agencies. This technology enables improved interoperability of separate linear referencing models. Numerous linear referencing models can be more successfully conflated, updated, cross-referenced, and rep- resented in different manners (e.g., varying scales, tempo- ral maintenance, and analysis). An example of proprietary software with these capabilities is discussed in a white paper by Intergraph Mapping & GeoSpatial Solutions (2012). CLOUD COMPUTING Cloud computing is a new technology in which computa- tional resources (both hardware and software) are provided to individuals or organizations remotely through the Internet rather than directly on oneâs own computer. These systems can include data storage, specific software, computing plat- forms, operating systems, and computer infrastructure. This technology offers users the flexibility to access cloud-based applications not only from desktop or laptop computers, but also from tablets or smartphones, which have less comput- ing power, through secure Internet connections. This can be beneficial to organizations by reducing the time required for integration of new applications and investment in hardware that quickly becomes obsolete. CURRENT DATA MANAGEMENT AND SOFTWARE IN TRANSPORTATION Asset Management The integration of LIDAR data into a GIS is an effective means of storing, analyzing, and visualizing data. The public works department in San Juan County, Washington, determined to explore this technology, found it had significant benefits to be realized. After a proprietary company spent roughly 600 hours scanning the countyâs roads, feature extraction was done on the data set for several areas of asset management. The public works department urged other departments to use markings, such as reflective paint or flags, to aid in asset extraction work- flows. Those who did not enter into the up-front effort can uti- lize the resulting point clouds delivered to the Washington State DOT in the future (Trojak 2011). The Oregon DOT (2012) completed a proof-of-concept project to evaluate earthmine as an asset management tool to integrate digital video logs, Mobile LIDAR, and traditional field data. It determined that the tools were reliable and provided significant gains in staff efficiency and safety ben- System GIS LRS Location Storage Type Geographic coordinates By linear length along a road Main Users State and federal departments, general public Maintenance crews, emergency responders Capable of Attribute Data sey sey Benefits ⢠Ease of specific map creation ⢠Interoperability of several software packages ⢠Wide capability of uses ⢠Integrates well with GNSS ⢠Tied to specific datums ⢠Visualization tool ⢠Can easily be converted to LRS ⢠All highways can be projected on the fly to a single coordinate system ⢠Simple, intuitive system ⢠Allows easy road quantification ⢠Needs only one measure of location attribute (approximate distance) ⢠Ease of asset inventory Limitations ⢠Some personnel may not have editing capabilities for GIS due to limited licenses ⢠Need field equipment (e.g., GPS) for 2 or 3 location attributes (x,y,z) ⢠Need for software updates (Some freeware GIS exist) ⢠Less accurate positioning compared with GIS ⢠Effective for only specific users ⢠Provides only one measure of location attribute (approximate distance) ⢠Difficult to analyze multiple highways together TABLE 23 GIS AND LRS COMPARISON TABLE
53 efits. The agency also evaluated a variety of implementation strategies. An important criterion for Oregon DOT in the evaluation was that the tool needed to be accessible to multi- ple staff across division boundaries. Many of the initial chal- lenges with its use during the study were able to be resolved. Finally, the report discusses lessons learned, including that it required a low learning curve because most staff thought they received sufficient training. Fifty percent of the staff reported that it took them only a few hours to become profi- cient with the tool. The Florida DOT analyzed the agencyâs current transit performances and needs using GIS, social-demographic information, and transit forecasting software. This study reports the need to develop a GIS data clearinghouse with data QA/QC methods, interface design for end users as well as input users, standards, and data conversion techniques (Cevallos and Catala 2011). Many organizations such as the West Virginia DOT have been developing and implementing LRSs throughout past decades. With the improvements of geospatial locating, the West Virginia DOT decided to update the agencyâs LRS to a seamless, accurate, current picture of roadways and assets. Portions of this system are functioning currently, but further work needs to be done to fully integrate all of the necessary data (Yoo 2010). The Florida DOT has been using both GIS and LRS for more than two decades. When it was determined that the agencyâs system was becoming ill-equipped to handle the large amounts of geospatial data coming in, they looked to employ new techniques to their LRS system, termed straight- line diagram. A prototype system has been explored to address these complications in web-based application modules (Ibaugh et al. 2007). Geospatial Enablement The Kansas DOT has documented a geospatial enablement plan with the agencyâs GIS system. This document aims to determine specific geospatial goals related to GIS and, one by one, put together a framework to attain these goals. The key goals of this enablement involve incorporating geo spatial referencing to existing business functions, allowing geo spatial information to be freely viewed by stakeholders (e.g., the general public, state organizations, and overseeing regula- tory committees), serving geospatial operability through a hosted website, seamlessly incorporating data to and from other business entities, and bringing geospatial solutions to the forefront of popular workings with Kansas DOT through training and education. Through this geospatial enablement plan, certain developed standards, specifications, and best practices were synthesized and recommendations were made as to how these standards could be incorporated into the Kan- sas DOT workflow. These standards include Kansas DOT internal LRS, Open Geospatial Consortium, Federal Geo- graphic Data Committee (FGDC), FGDC metadata, Kansas DOT internal metadata, Topologically Integrated Geographic Encoding and Referencing, NGS, Digital Orthophoto Quad- rangle, Kansas GIS Policy Board, FHWA cartographic stan- dards, and USGS national map (Intergraph 2005). The Minnesota DOT has grown its use of GIS into a statewide Geospatial Information Office, with other states creating similar system structures. This office, following ini- tial objectives set forth by the 2004 document and beyond, has the responsibility of maintaining statewide GIS data across all statewide government. A main goal of storing these types of offices in place was to standardize collected data, enhance the uses of GIS data, create accountability for these data, evaluate the ROI of governmental GIS hardware and software purchases, and more (Minnesota Governorâs Council 2005). The state of Oregon has a Framework Implementation Team (FIT, http://www.oregon.gov/DAS/EISPD/GEO/pages/fit/fit. aspx), which coordinates GIS data among various agencies. The data are made available online and shared among all state agencies. The team also develops standards and specifications for various types of GIS data within several themes, includ- ing administrative boundaries, bioscience, cadastral, climate elevation, geodetic control, geoscience, hazards, preparedness, hydrography, imagery, land use/land cover, transportation, utilities, and reference. The Oregon DOT is an active partici- pant in this team. Pavement Management Systems In a typical DOT, roughly 60% of assets are related to pave- ment structure. In 2004, Flintsch et al. compiled a synthesis of pavement management systems (PMSs) and how they can be used in conjunction with GIS. Similar to this geospatial synthesis, information was evaluated from a questionnaire distributed to geospatial representatives from DOTs and a thorough literature review was completed involving case studies from Tennessee, Virginia, Illinois, Iowa, Ohio, Flor- ida, Wisconsin, Pennsylvania, Georgia, Kansas, Arizona, and several local jurisdictions. Some of the problems identi- fied with using a PMS with a GIS were consistent referencing methods, the labor required to maintain database informa- tion, GNSS accuracies, effectively incorporating temporal aspects, the differing levels of details needed, unrealistic expectations from end users, and learning curve requirements to some GISs. At the time of print, this research showed that the main uses for GISs was map generation and database inte- gration. It did, however, show need-based GISs and PMSs. General Transportation Freight transport is an important concern for many states. The Washington State DOT examined the feasibility and effective- ness of a GIS-based freight transport module. Key research went into the concept of resilience in this industry. This
54 knowledge was applied to the freight transport module of two important industries in Washington: diesel fuel and potatoes. Conclusions come for specific questions asked of discrete industries contained in this freight transport framework. It is clear this valuable QA/QC quantification technique can be applied to many different areas of freight transport (Goodchild 2009). In 2005, the Illinois DOT created a GIS-based signal- ized intersection inventory system throughout district 6 of the agency. This system incorporates approaching photos and video, as well as signal and detection types of location- based, signalized intersections. A training course for employ- ees to use software effectively has been noted as a beneficial part of the deliverables in this study (Sun et al. 2005). Other efforts under way at the Illinois DOT are a GIS-based struc- ture inventory to aid with asset management (Conlon 2010). Geotechnical New Hampshire has created a hazard rating system utiliz- ing a GIS platform; 380 rock cuts on highways throughout the state with hazard implications were identified and logged into a GIS along with photos and descriptions. This addresses safety concerns with the identification, hazard rating, and tracking and monitoring of these cuts (Fish and Lane 2002). Hydrological and Environmental The Indiana DOT (INDOT), in response to the EPA require- ment of the permitting of stormwater discharge systems in site developments, uses GIS to help manage these efforts. Researchers at Purdue University and INDOT created a GIS layer to manage the geospatial location of manholes and receiving waterways. Although GIS was not used as an anal- ysis tool for the stormwater pollution levels, it was essen- tial to provide the geospatial framework of the system as a whole. Now that this information is in the GIS, they are able to use it in many different applications, and when new man- holes are created, the integration into the system is easy (Cor- son 2004). Other uses of GIS at INDOT are the evaluation of potential environmental impact of DOT facilities on their surrounding environment and an analysis of pavement fric- tion data for asphalt rehabilitation (Zhu 2000; Corson 2003).
