AM/FM 101: The GIS Mind-Meld
Mark R. Mace AM/FM System Analyst, Ohio Edison Company 253 White Pond Drive, Akron, Ohio 44320 Abstract AM/FM/GIS Systems are comprised of several key components:
An overview of the system architecture layers will also be presented, including: communications network, base software, application software, and computing hardware. Information presented is meant to be common to utility industries and vendor independent. Specific objectives for attendees:
Let’s start with GIS - Geographic Information System - and some helpful definitions: - A group or arrangement of parts that relate to or interact with each other in such a way as to form a whole; Any orderly group of logically related facts; An orderly method, plan or procedure. Information: Anything that reduces uncertainty; Knowledge acquired or derived; Timely or specific knowledge. Geograpy: The science that describes the surface of the earth and its associated physical, biological, economic, political and demographic characteristics; The physical aspects, features, ... of a place or area. From (Geo - Earth + Graphein -to describe). Automatic: Capable of moving or operating, at least partly, without human control or intervention; Computerized. Maminw A representation, especial] y on a flat surface, of any region or part of the earth. Facilities: A set of machines, tools, apparatus comprising an enterprise or business; The buildings and equipment needed for any institution (Plant). Management: The skillful use of means to accomplish a purpose. So, in practical terms, a GIS is an orderly set of rules and methods to manage information with a geographic component. For AM/FM, first the FM portion. Facilities Management is the skillful use of company assets to accomplish business goals. If we are in business to provide electric service to customers, some assets/plant or equipment will be needed. Information about them such as inspection/maintenance dates, current capacities (line, vaults, ducts), and economics will be needed for us to use them wisely and pro-actively. Automated Mapping can then be added for computerized maintenance of map products for both workstation displays and paper or even micro-fiche. Components Now that we understand what a GIS is, let’s look at the components of a system. Today’s systems have a data base, a spatial engine, a connectivity model and employ a GUI - a Geographical User Interface. Data Base The data base is the most important part of the system because that is where the information vital to the business is kept, maintained and managed. The value of data bases has been demonstrated and is well known. That value is only increased by adding the geographical attributes In some ways, adding geographic characteristics has clouded the issues of true importance and caused many implementations to go astray. When deciding what a GIS should do -or not do - it will be very valuable for users and programmers to step back and temporarily ignore the maps and displays, symbols and symbologies -- in short to forget the graphics “glitz”. Once this is done it will be possible to focus on the key business problems at hand - the “whys” of a system. You may then “remember” the graphics and maps, when it is time to implementation details - the “hews”. Be forewarned, however, that this priority system will be very difficult to maintain. Project representatives from user areas are often those most involved in maps and records, and programmers often become “drugged” by the technology. It is most important for the managers, especially project managers, to keep asking “why”. This will maximize the value of the system to the company. The data base is where other systems are also tied to geography. What separates this data base from others is the coordinate information - what brings this system together with others is the system of keys or common attributes - just like any other data base has to be integrated with corporate information. This is the true power of GIS -- the ability to provide and incorporate geographic relationships. By relating two sets of data to geography, a new analysis may be performed by deriving relationships between the original two. As an example, customers may be assigned point locations. Next, company operating districts or divisions might be assigned locations as polygons. An analysis might then be performed on customer counts by division. There are two ways to add geographic components through data conversion: (1)Digitize using some geographical reference (2) Geocode using attributes to derive location based on a correlation to existing geographic features. Spatial Engine The next key component is the Spatial Engine. Of the geographic tools provided by the ‘ software vendor, this may be the most important and most powerful. This engine allows analysis to be performed based on geographic locations. This tool allows explicit coordinate locations for points lines and polygons to be incorporated in implicit analysis. Another example may be helpful. An airport maybe assigned a geographic location. Depending on our scale requirements we might use a point or a polygon, but for now let’s assume we use a point, (X, Y). We could then assign line locations for all transmission lines. Using the spatial engine we could inquire for all transmission lines within one mile of the airport. The crucial difference in this analysis is that we made no additional explicit references between airports and transmission lines. By assigning locations in the form of geographic attributes, and employing the spatial engine, we have derived these relationships on the fly - as needed - with no long-term explicit data to be maintained other than the geographic components of each. -Connectivity Model The third key component is the connectivity model. Technically, this might be considered part of the data base or possibly part of the vendor toolkit, but it is worthy of separate discussion here. The connectivity model is how we maintain connections between our facilities and our customers - the things we need to run our business. Why? Because connection is a fundamental part of the reason we are in business. It is vitally important to know that a certain customer is connected to a certain waterline or electric transformer. If the customer reports an outage we know where to start. Economics may also be associated with feed paths (circuits), and the notion of profit becomes directly associated with service. This connectivity model may be expanded to include a direction attribute if needed. Geographical User Interface Finally, we get to the GUI - the geographical user interface. This is more than the traditional “graphical user interface” because it allows the user to interact with the system “geo’’-graphically. The GUI is typically used to maintain the geographic component of the data base. It is also used to present the results of analyses to the user. Often the GUI is a key part of application development since it is tailored to allow users to efficiently uerform business functions. Communicating information geographically is a very powerful and effective method. Example If we assume that the data base has been populated, the spatial engine is operational, the connectivity model built and the GUI functions as needed, we may find it useful to step through a sample application and discuss the functions of the key components. Sample Business Problem Let’s say that a tornado has been sighted in a certain area and we want to prepare a list of critical customers which could be affected. We might place the sighting at an (X,Y) point, then look for all substations within a five mile radius. From the substation list we could find all circuits potentially affected, then trace all circuits to construct a list of customers which could be affected. We could then select from that list those customers designated as “critical”. We might then highlight those customers on the display and ask if the user would like to save the file, print a report or produce a map with the streets and critical customers plotted. To solve this problem we have employed the critical components of the AM/FM/GIS. Let’s examine each step: Step 1: We used the GIS to place a point, then employed the spatial engine to find substations within 5 miles of that point Step 2: We used the data base to find circuits fed from those substations Step 3: We used the connectivity model to trace each of those circuits until we found all customers fed by those circuits Step 4: We used the data base to select all critical customers from that list Step 5: We used the GIS to highlight those critical customers on the geographic reference and optionally produced that geographic information as a map product. Architectures Finally, we must discuss the architectures - the pieces that make all of this possible. This may be considered an overview only. Network At the very foundation is the network - the physical connection between the computers and communications protocols used to transfer information between them. This might be local area net (LAN), wide area network (WAN) or Internet. Hardware Next, we have the hardware -- the computer systems used for data base management, applications and user workstations. We would also include such peripheral devices as disk drives, plotters, monitors, etc. For simplicity we can loosely consider the Operating System as part of the hardware group as well. GIS Software Then we have the GIS software - the graphic and geographic tools, spatial engine, etc., provided by the vendor. This will be the basis of a long-standing “love-hate” relationship between you and the vendor you select. Data Base Management System Next we have the data base management system used. Application Software Then the Application Software which employs functions of the DBMS, GIS software and even the Operating System as needed. Again, for sake of simplicity we will include the GUI in this category. Each layer or group must function on its own as well as in conjunction with all of the others. A breakdown at any point carries the same result: no benefits gained until the problem is resolved. This is a difficult issue in the face of unavoidable changes in every category. Conclusion So, a GIS is an information system designed to store, maintain, manage and employ corporate information by means of a geographic attribute or attributes. The key components in a GIS are the data base, the spatial engine, the connectivity model and the geoma~hical user interface. These components can be combined along with geographic data from multiple sources to perform highly sophisticated applications and analyses. The underlying architectures required for this kind of application are extremely intricate and dreadfully complex but are capable of stable performance if implemented and managed properly. In the face of the tremendous technologies involved, constantly remind yourselves of the business problems to be solved. Always ask “WHY” before you ask “HOW”. Don’t cheat your company - your project - or yourself - by letting your focus be shifted to anything else. | ||
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