Utility Mapping 45 4.2 Processing GPR data Ground Penetrating Radar (GPR) generated images called radargram which contains hyperbolas that represent object beneath the earth surface. These hyperbolas are formed by the reflection of signals emitted by the GPR device. 4.2.1 Interpreting radargram image Ground Penetrating Radar (GPR) generated images called radargram which contains hyperbolas. Interpretation of datasets (radargram) in detecting underground utility is a tedious process, where such operations would require a considerable amount of time and effort. Figure 4.2 : Formation of hyperbola in GPR imaging Figure 4.3 : Hyperbolic image gives the position and depth of utility.
Utility Mapping 46 Figure 4.5 : Position of utility close to each other Figure 4.4 : Utility at varying depth Figure 4.5 : GPR profile showing subsurface pipes of different size present at different depth
Utility Mapping 47 4.2.2 Indicate position, depth and arch Position, depth and arch in radargram image can indicate easily by indicator. Commonly, indicator provided in GPR software. Figure 4.6 : Indicator of position, depth and arch i) Position Indicator - Position Indicator Vertical cross-hair is tied to the odometer and corresponds to the location at the center of the GPR sensor. As the cart is pulled backwards, the Position Indicator moves to indicate the current location of the cart in the image. ii) Depth Indicator - Depth Indicator Horizontal cross-hair found at the peak of the soil type indicator arch indicating the depth. - The Depth Indicator moves up or down using the Arch Up and Down buttons. iii) Arch Indicator - Indicator Arch Idealized representation of a typical pipe-like target response observed on the GPR image. - The width of the arch is controlled by soil type setting. The soil type setting is changed using the Arch buttons. Increasing the soil type makes the indicator arch wider while decreasing the soil type makes it narrower.
Utility Mapping 48 4.2.3 Determine material type (Using GPR to identify type of utility) Geophysical Survey System (GSSI) Academy has done their research toward this. One of the most critical tasks in using Ground Penetrating Radar, or GPR, technology is that of determining material types for materials in the ground. Given that GPR technology works by transmitting and receiving a high frequency electromagnetic wave through the ground, distinguishing between different materials typically air, water, and metal is possible by analysing the degree of difference in the dielectric constant of the material. Dielectric constant measures how easily radar waves move through a material. For underground utility locating, the three main material types encountered are metal, air, and water. Determining material type is possible by analysing dielectric change, or the change in how easily radar waves penetrate the ground as compared with the material in the ground. The larger the dielectric change, the stronger the reflection and the brighter the image produced on the GPR control unit. Greater change produces brighter targets on screen, and smaller changes produce dimmer targets. The colour of the target onscreen indicates whether the dielectric change is positive or negative. Figure 4.7 : Determining material by analysing dielectric change (GSSI Academy, 2020) Metal has an infinite dielectric constant. GPR cannot pass through metal because it’s a perfect reflector for GPR energy and so it will be shown onscreen as the brightest possible positive dielectric change.
Utility Mapping 49 Figure 4.8 : Comparison between metallic and non-metallic pipe hyperbolic image. Hyperbolic image for metallic pipe is brighter than non-metallic pipe. 4.2.4 Processing GPR data using software The suitable software was used in the pre-processing phase. The software was chosen based on its capabilities to enhance and improve the quality of GPR dataset quickly and easily. It was specially designed for processing and interpretation. Example software are MALA Object Mapper, EKKO-Project, ReflexW 6.5 version and others. Figure 4.9 : MALÅ Object Mapper is visualization software for processing, analysing and interpreting GPR utility data
Utility Mapping 50 4.2.4.1 EKKO Project software EKKO Project is one of the software for processing data by generating report and interpreting GPR data. Screenshot image or GPR project file (.GPZ) can be exported or transfer to PC via USB. If data was collected with GPS (internal or external), a .KMZ file is also generated. This contains positional information and can easily be opened in Google Earth. Figure 4.10 : Transfer to PC using USB i) Open screenshot image or GPR project file in EKKO Project All GPR data are contain in project file called .GPZ file. It can be opened in EKKO Project software. Open > select .GPZ file. Below figure is the main screen of software that view ZigZagLine.GPZ file once opened. It will viewed MapView and Line Preview. Figure 4.11 : Open GPR project file
Utility Mapping 51 a) MapView From the above figure, MapView view tracking line of GPR in zig zag along 313.3m. The length and other data are stated detail at right screen. MapView show the position of GPR tracking (Project Coordinate system) in Latitute and Longitude . b) Line Preview From above figure, Line Preview viewed the radargram image that contain hyperbolic. This radargram or hyperbolic image are detected by GPR along tracking line. It also represents position (X axis) along 313.3m of tracking line and depth of hyperbolic (Y axis) represent utility. ii) Add interpreting to the utility or on hyperbolic images The most important aspect is interpreting the hyperbolic image. From Line Preview image, we will add interpretation to the utility and give the direction and special relationship in the MapView. This is the step to start: a) Open GPR line in Line View Model o By referring above figure, Select LINE 2 name at Project Explore > Click/Select LineView Icon OR double click LINE 2 name. o LineView model or radargram image contain hyperbolic along 313.3m will be display as below : Figure 4.12 : Line View image o Zoom in the image and hyperbolic can seen clearly. o Then, play with the gain to find out the best look of hyperbolic image as below:
Utility Mapping 52 Figure 4.13 : Adjusted gain to find out best look of hyperbolic image b) Interpreting and add interpretation There are three types of interpretation in this software, that is Point, Polyline and Box. o When scroll along position (Y axis), it seen to be 2 particulars hyperbola that located deep and shallow as below : Figure 4.14: Image show shallow and deep hyperbolic
Utility Mapping 53 c) Add Point Interpretation o Click Create New Interpretation icon and Create New Interpretation dialog box will display : o Refer on below figure, choose Tool as Point, name interpretation as Deep Utility, adjust color as red, adjust setting and click OK. o Then at LineView Model, Select Deep Utility and add point (red colour) at the top of hyperbolic as deep utility.
Utility Mapping 54 o Red dotted also seen in MapView as below. o Then add interpretation for shallow utility as blue dot. ▪ Create New Interpretation ▪ Choose Point at Tool, name interpretation as Shallow Utility, adjust color as blue, adjust setting and click OK. ▪ In Line Preview image add blue dot on top of shallow hyperbolic ▪ Then, blue dot also seen in MapView as below figure
Utility Mapping 55 o Add Horizon Line Interpretation ▪ Horizon line also can add in Line Preview image if want to know what exactly line image that seen in radargram. ▪ In Create New Interpretation dialog box, choose Horizon at Template. ▪ Horizon is a polyline. Draw the polyline at line image in radargram in green color as seen in below figure. o Add Box Interpretation ▪ In radargram image, there are many unknow image appear. It can be identified by adding box interpretation. ▪ In Create New Interpretation dialog box, choose Box at Template. ▪ Draw Box at unknown image as below figure.
Utility Mapping 56 o After done add interpretation for horizon and box, it will appear in MapView as below figure. o As we can see, it can be interpreted that green polyline or horizon is a tracking line that reflected from GPR o Brown box that annotates at the image is a U shape when GPR turn around and coming back in the other direction. The box helps quickly to interpret the U shape feature as a layer distorted when the GPR turn around in the zig zag. o Then, we also can add an annotation on radargram image as a label. In Create New Interpretation dialog box, choose Annotation in Tool. For example, label 1 point as Crossing Point in Line Preview. Then the label will appear in MapView.
Utility Mapping 57 d) Interpreting Depth Slice Depth Slices are maps of GRP signal reflection strength at a certain depth. Depth slicing produces a 2D image of GPR data at varying depth based on signal amplitude. When locating in an area with many utilities, depth slicing is a powerful way of looking for linear subsurface objects likely to be utilities. Below figure is a depth slice that generated from GPR scanning. The depth slice shows the features running through Y and X axis. Depth slice is powerful but require utilities producing a strong reflection. Its easier to understand if depth slice can show the image that wanted and confirm. Figure 4.15: Depth slice image The two reason that can recognize the image is the object or utilities is because of : i) the target has the contrast color compared to the other image around it. So, we able to differentiate the responses of the target versus all the other object in the boundary of subsurface. Based on above figure the orange color is contrast that confirming the target is there. ii) the image must have unique shape and orientation that allow you to differentiate with the other object. Based on above figure the contrast color of image has orientation vertically and some is horizontally.
Utility Mapping 58 But sometimes the depth slice or 3D images did not straight to understand because of very week responds or not contract as shows in below figure. Figure 4.16: Depth slice image show very week respond So to recognize and confirm the contrast image is the utility is need to add interpretation at hyperbolic image in Line Preview because it will appear in it. Above image is the example of weak hyperbolic image that will not display or difficult to see in depth slice. Figure 4.17: Add point interpretation on hyperbolic image The way to solve or recognize is by adding interpretation with point at weak hyperbolic image. Then the interpretation point will display on depth slice in MapView as seen in below figure. Based on the linearity, your confident toward image as a utility is increased.
Utility Mapping 59 Figure 4.18: Interpretation point appear in depth slice that weak respond e) Generate interpretation report After adding interpretation on hyperbolic image, all data can save and extract by generating report in .csv format. Choose Tool menu – Report – Project Report (.CSV) Or Select GPR Summary Report icon - Project Report (.CSV). All points that interpreted are generated in report as below table. All the GPR data are extracted in the report. The most importance information from the table are depth, position, x and Y meter and Latitude and Longitude. Figure 4.19: Detail of interpretation in .csv format
Utility Mapping 60 f) Save interpretation and display data in Google Earth If the data collected with GPS, the other way to save is in .kmz format. Once it saved, the interpretation data will display in Google Earth as show in below figure. Click on Tools – Report – Google Earth (KMZ). Figure 4.20 : Interpretation point show in Google Earth g) Save interpretation data as CAD (DXF) The important way is to save and generate report in CAD format that is .dxf. Click on Tools – Report – CADD (DXF). Once open the .dxf format file in Autocad it will generate as show in below figure. Figure 4.21: Open DXF file in CADD
Utility Mapping 61 Figure 4.22: Interpretation point appear in depth slice that weak respond If turn off the GPR line, the interpretation points are in here for shallow and deep utility. Then the point will be used to draw utility plan. iii) Display in 3D Preview X and Y view are easier seen from generated radargram image or depth slice. X view known as long section meanwhile Y view known as cross section. From the below figure, blue image is depth slice or radargram, right image is cross section and below depth slice image is long section. This three picture or view are related each other and will appear in EKKO Project software by clicking 3D preview.
Utility Mapping 62 Y view or Cross Section at 1.7 metre depth X view or Long Section along 5m
Utility Mapping 63 4.3 Processing control and topography survey data In CDS software, its create many junction files when opens a New job. All the files must be stored in a specified folder. So that, it enables the user to move the folder to another directory without misplacing the files. 4.3.1 Creating A New Survey Job Start CDS from the Programs Menu or doube click on CDS icon. To create a new survey job, Pull down the “File” menu, and select “New”; or Click on “ New Job” icon in toolbar. A dialog box will appear. Create a new folder in the specified directory. For this training, a new folder has been created in desktop. All the related files will be saved in that folder from time to time.
Utility Mapping 64 Tick “New Job”. Replace the ‘db.*’ which appears with your project title. You may fill in the other descriptive fields if you wish. Once you have completed all the fields you wish to use, Select the “Open” button. Once you save the new job, your screen will appear as seen below, and you will see that the new job has appeared with a blank screen. To recognize the selected job, the screen appear to have the job title on the top bar as shown in below picture.
Utility Mapping 65 4.3.2 Transfer Raw Data from Total Station In this part, it shows all the procedure to download measurement data from a data recorder such as total station. This is the crucial part because if the raw data are not downloaded properly, the next chapter cannot be done. 4.3.2.1 Communicating with a Total Station There are 3 components involved, which are: i. Computer (CDS Software installed) Figure 4.13: Dekstop Computer ii. Cable (for communicating an exernal instruments by serial signal connector or USB) Figure 4.14: Topcon GTS-230N Serial Connecter iii. Total Station (data recorder) Figure 4.15: Topcon GTS-230N Series The total station must be connected with computer by using cable.
Utility Mapping 66 4.3.2.2 Total Station Download Parameter Setting The menu for “Setting Parameter for Data Communication” is different for each total station available in the market such as Topcon, Leica, Sokkia, Nikon and so on. In this training manual, the topography data have been collected using the Topcon GTS-230N Series model. The basic theory is same but the menu arrangement is different between total station brands. Notice: The parameter must be same with the “Communications In” setting in the CDS sofware. i. Items Of The Parameter Figure 4.16: Items Of The Parameter The items should be set as follows: Baud rate : 9600; Data bits: 8; Stop bits: 2; Parity: None; Flow control: By line then wait (GTS6) ii. Procedure To Set The Parameter
Utility Mapping 67 Figure 4.17: Procedure To Set The Parameter 4.3.2.3 CDS Software Download Parameter Setting Pull down “Entry” menu; Select on “Data Collectors” menu; and Click on “Collect Raw Data from Data Collector”; Terminal Window, Untitled-comms32 will appear. Pull down “Setting” menu; and Click on “Communications In” Untitled-comms32
Utility Mapping 68 Enter the required information in the input communication. Please ensure the parameters setting is same with total station; Baud rate : 9600; Data bits: 8; Stop bits: 2; Parity: None ; Flow control: By line then wait (GTS6) After all the informations included, Click “OK”. 4.3.2.4 Raw Data Download Procedures There are two parts involved in this step: i. CDS Software ii. Total Station ALERT: Please hit the transfer button in the CDS software before push transfer button at total station. i. CDS Software
Utility Mapping 69 From Terminal Window “Untitled-comms32”; Pull down “Transfer” menu; Then, Click on “Data to Computer”. ii. Total Station Sending a Measured data file. For step 7, select the project by entering its name or press [F2] (LIST) to choose the file.
Utility Mapping 70 Figure 4.18: Sending a Measured data file To cancel the sending, press the [F4] (STOP) key. If all the settings are correct, the terminal window “Untitled-comms32” should be as shown in Figure 3.6; Figure 4.19: Untitled-comms32 After finish downloading, press Escape keyboard “ESC” and save the data (‘save’ it with file name *.raw) Figure 4.20 : Raw Data Format 4.3.2.5 Import Raw Data In this chapter, it shows the procedure to import raw data to a CDS stadia file format. Each total station have their own raw data format. As data processor, you must know which format the raw data belong using the brand of the total station. After download the raw data, you need to open the raw data in the CDS stadia file to check the recorded data in good shape or not.
Utility Mapping 71 4.3.2.6 Import Raw Data to a CDS Stadia Format Pull down “Entry” menu; Select “Data Collectors” menu; and Click on “Import Raw Data”. Import raw data screen will appear, there are many types of total station brands available to choose. Select “Topcon” as the total station brand and “FC5,GTS6” as GTS239N raw data format. Click on “Browse...” to locate the raw file. Raw Data File screen will appear. Choose the raw file of the project as example ‘raw job 1_training manual’. Then, click on “Open”.
Utility Mapping 72 Click on “OK”; Click on “OK”; Click on “OK”; Click on “Yes”; Stadia file for the job have been created. As you can see in the Figure 4.0, the stadia title at the top of the bar is ‘stad1.training manual’. It’s mean, this is the first stadia file for the project.
Utility Mapping 73 When you opened another stadia file, it’s automatically numbering the stadia as example ‘stadia2.training manual’, and ‘stadia3.training manual’. Figure 4.21: Stadia 1 File
Utility Mapping 74 4.3.3 Topography Surveying Data Processing This chapter explains about the procedure to process stadia file in order to calculate coordinates and height for measurement data. Then, the last step is to show the topography data graphically and export into drawing (*.dwg) format. 4.3.3.1 Open The Stadia Files Pull down “Entry” menu; Click on “Electronic Stadia...”; Tick on “Stadia”; Then, Click on “Browse...” to locate the stadia file or Click On “Open Existing” if the file already there;
Utility Mapping 75 Select the previous stadia file as example “stad1.training manual”; Then, Click on “Open”; The stadia file table will appear. As you can see, all the information collected in the field have been recorded properly.
Utility Mapping 76 Below is the descriptin for the shortform available in the stadia table: Short form Description Fnote Foot note to show information about occupied station as example point numbering, coding and instrument height. AT/BS The bearing direction from occupied station to backsight station. HZ/DH The bearing and distance direction from occupied station to detail/ topography data. Pt# The numbering for detail/ topography data. Usually in real work the surveyor need to assign different numbering to prevent problems in the future. As example: Numbering 1- 100 for station number. Numbering 1000 – 9999 for detail/topography data. Tips: The numbering for detail data recorded from station 1 must use 1000, from station 2 must use 2000, from station 3 must use 3000. The reason is, when facing problems with detail data, the surveyor or draughtsman can detect the problems easily. Ht/Diff Vertical height to calculate the detail height values. Ht Foresight prism height or mini prism height. PC The attribute/ code data to represent the spatial data collected at the field. 4.3.3.2 Entering Control Points Values for Datum To enter the coordinates and height values of control points for datum, we need to insert new row before the first station row. To do this, click on “the first row” (please make sure the row is highlighted after the click).
Utility Mapping 77 Then, Press the “Insert” or (Ins) keyboard to add new row. The new row have been added successfully. To enter the coordinates and height of control points, make sure the setting for new row as follows: i. Type: STN ii. Pt#: Occupied and backsight numbering station for datum. In this job, the station number for occupied station is 101 and backsight is 100. iii. East/ North: The coordinates for datum. iv. Height: The height/ mean sea level values for the control points. v. PC: Attribute for the numbering data.
Utility Mapping 78 4.3.3.4 Calculate Coordinates and Heights Click on “Options” menu; and Select on “Calculate Coordinates” to compute all the coordinates and height for detail measurement data; Then, Pull down “Options” menu; Click on “Show Coordinates”; The coordinates and height for each data are shown as below: 4.3.3.5 Show Topography Details Graphically After all coordinates and height for measurement data have been calculated. You need to show topography details graphically. Pull down “Options” menu; Click on “Store Data in Database”;
Utility Mapping 79 Tick on “All”; Then, Click on “OK”; Press on CDS shorcut key “Z” and “E” for Zoom Extents. Below is the results. The data show in the screen is in Point Numbers Layer, to change it into another layer, Click “Layers” icon in toolbar; Layers, Modes, Surface Parameters screen will appear. Click “Modes-Display” tab;
Utility Mapping 80 The results as shown in Figure 4.22 and 4.23: Figure 4.22: Layer Modes in Height Layer Tick on “Modes” Tick on “On Height” This will open layer for height Last, Click on “OK”.
Utility Mapping 81 Figure 4.23: Layer Modes in Codes Layer 4.3.3.6 Export to Drawing Format The details graphic in CDS can be exported to drawing format. There are several settings of parameter need to be checked through the CDS software. 4.3.3.7 Parameter Need To Be Checked Before Export Pull down “File” menu; Click on “Plot Parameters”; View-Print-Export Control screen will appear. Click on “Sheet Details” tab;
Utility Mapping 82 Click on “Point Param” tab; Click on “Point Selection” tab; Then, click again on “Reset”; Enter file name for the drawing Tick on “3d to dwg/dxf” (the height values/ z in 3d projection Untick “Use layer with point” (to break each layer into many Select point shape “ . “ from the list Tick on “Heights”, “Point”, and “Codes” layer Change “Acc” to 3 (means the height values in 3 decimal point
Utility Mapping 83 Tick on “All”; Then, Click on “OK”; Click on “String Param” tab; Tick on “Strings”, “Bearings” and “Distances”; Then, Click on “OK”.
Utility Mapping 84 4.3.3.8 Export To *.dwg Format Pull down “File” menu; Click on “Export DWG”. Click on “Yes” to open the drawing. Below is the topography details graphic in AutoCAD drawing. The next step is to edit and produce Engineering Plan or Topography Plan for the project.
Utility Mapping 85 1. Impulse GPR works by sending electromagnetic energy in very short pulse into the ground. Reflection signal captured by the receiver after hitting an object in the ground is process to produce …... E. Utility Plan F. Graphic image G. Depth image H. Hyperbolic image 2. Below diagram is GPR tracking route. Name A. A. Long Section B. Cross Section C. GPR route D. Underground utility 3. Below are the main component of Global Positioning System (GPS) except A. Receiver B. Antenna & cabling C. Hardware D. Recorder unit A
Utility Mapping 86 Introduction Utility plan or map is main deliverable of underground utility in hardcopy or softcopy format. It provides all the detail about utility on and underground based on services provided on that area. Utility plan in Malaysia has been standardised by JUPEM in Standard Guidelines of Underground Utility Mapping (2006). 5.1 Content and Features of Utility Plan Commonly, the content of utility plans are same goes as other plan but it focus to present utility feature especially position and depth. Below are content and features of utility plan: i) Symbol Standard symbol is follow to Malaysia Standard Geographic Information/Geomatic Features and Attribute Code (MS1759 : 2015). 5.0 UTILITY PLAN
Utility Mapping 87 Figure 5.1: Example of attribute code for symbol ii) Colour Colour used to indicate utility type with different code. UTILITIES COLOR SYMBOL Electrical Red -PGas Yellow -GCommunication Orange -TWater Blue -WSewer Green -S- (Source : Circular No. 1/2016 by JUPEM) Table 5.2 : Standard colour code to differentiate utility type iii) Title Title plan or map commonly to namely the plan and indicate the purpose.
Utility Mapping 88 iv) Line code and style The line code and style can differentiate the type of cable and usage. Figure 5.3: Different line code and style to differentiate utility type for telecommunication utility. Utility stated in quality level A v) Label of Feature It is the method to differentiate between the quality levels, utility type, ownership, date of depiction, accuracy of surveyed appurtenance, endpoint of any utility data, active, abandoned, or out of service status, size, condition, number of joinly buried cables and encasement. Figure 5.4 : Labelling the utility diameter vi) Annotation Annotation should be appropriately used to ensure that it does not obscure other utility data. Figure 5.5 : Annotation, clear and can read easily vi. Legend Legend to define symbol on the plan.
Utility Mapping 89 vii. Name of building, street, road and river Official names of building as well as names of street, roads and rivers shall be shown. viii. North Arrow An arrow symbol indicates the direction of the grid north and the true north. ix. Scale Map scale refers to the relationship (or ratio) between distance on plan or map in earth distance, graphic scale or both. For utility map, scale must be set in 1:500 or 1:1000. x. Date of Map The publication date of the map should be displayed. xi. Marginal Information Marginal information as usual includes such items as section, town, city and state names, scale, title, north arrow, legend, published date, disclaimer and others. xii. Disclaimer Disclaimers are used to limit and define the map author’s responsibility for the content, accuracy and currency of a map. Although some maps may require specialised disclaimers, the following disclaimer represents one suggestion. xiii. Longitudinal and Cross Section Longitudinal and cross section are not compulsory to provide in plan but separately. Both can be produced using software such as CDS, LISP apps etc. Next page is example of Longitudinal and Cross Section of Utility.
Utility Mapping 90 Figure 5.6 : Longitudinal and Cross Section
Utility Mapping 91 5.2 Preparing Utility Plan based on Standard Guideline by JUPEM Utility map must be prepared in hardcopy and softcopy format if required to submit to JUPEM. Besides following the basic deliverable and quality level attribute, below is others specification that stated also to follow. This specification is prepared by JUPEM and stated in Circular No. 2/2016, JUPEM (Pekeliling KPUP Bil. 2/2016). 5.2.1Hardcopy utility map i) Size : A0 or A1 ii) Layout : Landscape iii) Medium : Polyester Paper iv) Marginal Information : - Title - District/State - Scale : 1:500 or 1:1000 - North Arrow - Reference Number - Coordinate System - Verify by License Surveyor regarding Quality Attribute - Date of survey - Sign by License Surveyor v) Legend vi) Disclaimer vii) Limited (Terhad) 5.2.2 Softcopy or digital utility map Digital utility map has been prepared follow with below specification. This specification is prepared by JUPEM for standardization during submission to JUPEM for NUUD storage; i) Pdf format ii) Geopdf format
Utility Mapping 92 5.3Digital data of Utility Plan Digital data that submitted to JUPEM must comply with : i) Format Data In GIS format shapefile (.shp) , geodatabase (gdb) or Mapinfo (TAB) ii) Coordinate system In GDM2000 Rectified Skew Orthomorphic (RSO) and GDM2000 Cassini Soldner iii) Attribute code Attribute code must follow to Malaysia Standard Geographic Information/Geomatic Features and Attribute Code (MS1759 : 2015). 5.4Preparing utility plan in digital Utility plan can be produce using Autocad or other suitable software. AutoCAD is a commercial computer-aided design and drafting software application. This software often used for completing and editing raw data. Figure 5.7 :Example of utility plan drawing in Autocad software
Utility Mapping 93 5.5Spatial and attribute software (shapefile format) One of the requirements during submission plan to JUPEM is digital data. Digital data contain shapefile format involving spatial and attribute data that called GIS. Example GIS software is below: i) Quantum GIS (QGIS) Designed to store, retrieve, manage, display, and analyze all types of geographic and spatial data. This software is an open source which can be download freely on the internet. It shows the data in digital format and all data such as depth, service provider and others can be saved in the database. Such data are called attributes. Figure 5.8 : Example of utility drawing using QGIS ii) ArcGis It has the same function with QGIS where it can display and store geospatial data but ArcGIS is not an open source software, whereby we need to purchase its license
Utility Mapping 94 1. Code colour for each utility is different in map. Which colour is correct for the utility A. Red – water pipe B. Blue – Sewerage C. White – Gases D. Orange – Telecomunication cable 2. Standard scale of utility plan stated in circular is A. 1:500 B. 1:20000 C. 1:10000 D. 1:2000 3. During submission of utility plan, checking for digital data covers A. Coordinate system B. Software used C. Font size D. Size of digital data 4. Give the coordinate system used during processing data for producing plan A. WGS84 B. Latitute Longitude C. Rectified Skew Orthomorphic D. National Coordinate 5. One of the requirements of digital data is in GIS shapefile format. Give the suitable software to produce digital data in GIS shapefile format. A. Autocad B. Microsoft Word C. Civil Design Survey (CDS) D. ArcGis