UNIVERSITY OF TECHNOLOGY, SYDNEY

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1 THllS PAPER MUST NOT BE REMOVED TO BE RETURNED AT THE END OF THE EXAMINA'TION UNIVERSITY OF TECHNOLOGY, SYDNEY NAME: STUDENT NUMBER: COURSE: AUTUMN SEMESTER EXAMINATION 2007 Subject Number: GIs AND REMOTE SENSING TIME ALLOWED: 2 hours + 10 minutes START: 9:30 am - FINISH: 11 :40 am This paper is designed to be completed in 2 hours. An extra 10 minutes has been added to the time allowed and it is recommended that you use this time to read the paper before commencing to answer the questions ALL QUESTIONS ARE TO BE ANSWERED IN THE SPACES PROVIDED ON THE EXAMINATION PAPER THERE ARE FOUR (4) SECTIONS EACH SECTION IS WORTH 20 MARKS USE DIAGRAMS WHERE NECESSARY TO ILLUSTRATE YOUR ANSWERS

2 GIs d Remote Sensing Autumn SECTION A: MULTIPLE CHOICE For each question circle, or otherwise clearly mark, one correct answer only. Answer all questions in this section. (2 marks per question) 1. A critical attribute of spatial data is: (a) the quantifiable measure of a variable. (b) a written description of the location of data. (c) a coordinate value for the position of data. (d) the ability to use data in a calculation. 2. In GIs a graticule is best defined as: (a) a grid of x and y data coordinates. (b) a device for ground truthing satellite data. (c) the arrangement of pixels in a raster image. (d) the location of a reference point. 3. An example of continuous field data is: (a) council regions. (b) nutrient distribution across a state. (c) house distribution with a city (d) an arterial road network. 4. WGS84 is: (a) the standard map reference system for north America. (b) used as the basis for topographic map production in Australia. (c) the world standard geodetic reference system. (d) the UTM standard projection. 5. Toblers Proximity Law states: (a) if nearby objects are similar, then spatial autocorrelation will result. (b) there is a "spherical divergence" of similarity about an object that diminishes to zero. (c) the closer together two objects are, the more likely they are to covary. (d) everything is related, but near things are more closely related. 6. Indicate which of the following statements is incorrect: (a) Covariance among data results in redundancy. (b) Covariance and spatial autocorrelation are essentially the same thing. (c) Spatial autocorrelation in a non-random attribute of data. (d) A chessboard represents an extreme case of negative autocorrelation. 7. Electromagnetic radiation: (a) behaves as a wave function when in motion and a quantum function when stationary. (b) has zero mass when photons are at rest. (c) is transmitted by longitudinal oscillatory motion. (d) cannot be propagated in a vacuum.

3 GIs & Remote Sensing Autumn Electromagnetic radiation is produced by: (a) alternating currents in a body. (b) thermally induced vibration of molecules. (c) electrons jumping between different quantum levels. (d) all of the above. 9. Absorption of EMR in the Earth's atmosphere: (a) can be used to identify minerals in the near surface (b) in necessary for remote sensing of the ground (c) is useful for monitoring atmospheric gases (d) all of the above. 10. Radial relief displacement occurs on remotely sensed images because: (a) the scale of an image varies radially away from the centre. (b) vertical elevation differences on the ground project to different horizontal positions on the negative or sensor. (c) light from the edge of an image is dimmer than near the centre. (d) the lens distorts the image. End of Section A SECTION B: SHORT ANSWER QUESTIONS You must answer all questions in this section. (Each question is worth 2 marks) 1. If you were asked to determine the percentage of affected vegetation for an environmental analysis forming part of a development application, describe the type of map projection you would use, citing an example. Briefly explain why you chose this projection. 2. Briefly explain the difference between the terms geosynchronous and a geostationary when referring to Earth-orbiting artificial satellites.

4 GIs 8 Remote Sensing Autumn A histogram of digital numbers (DNs - the intensity values assigned to each pixel in the image for the particular wave band or channel being used) from a raster image has a bimodal distribution. Sketch such a histogram and briefly explain what it means Explain how you would add a layer to a display in ArcMapIArcGIS. 5. Explain what is meant by an elliptical orbit, including brief definitions of the terms apogee, perigee and focus. 6. Briefly explain why in satellite or aerial photography, focusing a camera to take images of the ground is unnecessary (you may support your answer with equations).

5 GIS & Remote Sensing Autumn Write a concise definition of the meaning of projection when referring to maps. In your answer, explain why projection is necessary when dealing with the surface of the Earth. 8. Briefly explain the use of Arccatalog in the ArcGlS system. 9. Explain what is meant by the term contrast stretching in the processing of a digital image, and briefly indicate why this might be necessary. 10. Write a brief definition of GIs. End of Section B

6 GIs & Remote Sensina Autumn SECTION C: FILL-IN MISSING WORDSILINES AND TRUEIFALSE There are eighteen (18) questions in this section, each worth 1 mark. Questions 1 to 8 require you to fill in the missing word with an appropriate choice from the list of twenty options given in the table immediately below. Each space requires a single word answer only. Questions 9 to 18 require you to indicate whether the statement given is true (T) or false (F) by unambiguously circling the correct option. Options for Missing words: shorter astronomy near infrared geophysics ultra violet decreases fields Meridian flux l ncreases attributes numbers parallel visible light data brightness numeric longer interval intensity 1. GIs tables contain as columns, and records as rows. 2. In geographic coordinates, a line of constant latitude is called a 3. Types of geographic attributes can be classified as nominal, ordinal, ratio or cyclic. 4. Remote sensing represents a sub-set of applications in the broad scientific field of 5. The of a remote source represents the energy emitted by the source and is independent of the observer. In contrast, the represents the energy being intercepted by the observer. 6. The range of electromagnetic radiation (EMR) wavelengths from 700 nm to 3000 nm (3.0 pm) represents the spectrum of 7. In a GIs Table of Attributes, a value can be represented by text or by 8. There is more energy associated with each quantum of EMR as the frequency or the wavelength becomes

7 GIs & Remote Sensing Autumn Rayleigh scattering causes the sky to be red at dusk. T/F The vis-viva equation {v2=~*(ml + m2)*[(2/r)-(l/a)]) describes circular orbits. Each UTM zone spans 6 degrees of longitude. The best possible resolution for Line Scanning Systems (LSS) is obtained for larger values of IFOV. A projected value of latitude is called an easting. The peak or modal value of the EMR emission spectra for a black body is a function of its surface temperature and the proximity of the observer. In GIs the term conflation indicates the operation of merging datasets. Remote sensing techniques detect and measure electromagnetic properties of objects that are not in direct contact with the observer. T/F The geoid adjusts the datum to local gravity variations. T/F The best statistical indicator for a confusion matrix is given by the Percent Correctly Classified (PCC) value. TIF End of Section C Section D commences on the next page

8 GIs 8 Remote Sensing Autumn SECTION D: CALCULATIONS AND EQUATIONS There are four (4) questions in this section. You must answer all questions. Some answers require calculations, others require explanations of an equation. You are permitted to use a calculator to determine the answer where appropriate, but you must show the step-by-step calculations used to reach the final answer in order to obtain full marks. Each question is worth 5 marks. 1. A topographic map has a scale of 1:10,000. Determine the length on the map of a segment that represents a distance on the ground of 100 m. 2. Wien's law describes the relationship between the peak wavelength of a black body (measured in m) and its temperature (measured in K) and is given by the relationship AM, = x 10" 1 T. Knowing that the Sun's surface temperature is 6000 K, calculate the wavelength of the peak of solar radiation and express the answer in mm. Briefly indicate if your answer agrees with observations of the sun.

9 GIs & Remote Sensing Autumn The following equation describes the motion of an orbiting body around a centre of mass. Describe the meaning of each term in this equation and briefly explain why the equation is important in the deployment of artificial satellites 4. The relationship is widely used in GIs analysis as a measure of spatial autocorrelation. Indicate the name given to this calculation, cite the range of values expected from the calculation and indicate what these values mean. Briefly explain the meaning and importance of spatial autocorrelation in the analysis of geographic data. Check that you have answered questions on every page of the examination before you submit END OF EXAMINATION