UniServe*Science News, Vol. 5, November 1996

Introduction to Remote Sensing Computer Aided Learning

Toni O'Neill is a Senior Lecturer in the School of Geosciences, University of Wollongong.

The Remote Sensing Computer Aided Learning (RSCAL) modules What is Remote Sensing?, Spectral Signatures (covering basic concepts of remote sensing) and Air Photo Interpretation and Multispectral Scanner Interpretation (covering the more complex issues of interpretation) make up this introduction to Remote Sensing. The aims are clearly set out at the beginning of each of module. Each module has a number of menu items and the students can do these sequentially or choose particular topics to revise.

The sections are arranged logically and each builds on the previous section. I have found for the initial student practical it works best for the students to work through the suggested sequence. In the two interpretive modules the programming is more sophisticated, more use is made of animation and the modules are more interactive.

The instructional section (classroom) of each module is followed by a practical test on which the student is scored. The answer is scored as correct or incorrect and a short correct explanation is shown before the presentation of the next question. Students need to take care when answering questions as spelling errors are scored as incorrect and some of the more lateral thinking students often give technically correct answers which may be scored as incorrect due to the limitations of the programming. Progressive test scores are shown on the student's screen and the final scores can be retrieved by the lecturer later. In the two more recent interpretive modules the test is in the form of a computer game. Students choose from three practical exercises structured as a remote sensing rally. Each rally occurs in a different geographical location (New York, Perth, or the Gold Coast) and a range of remotely sensed images are used. This allows for a range of different types of environments to be experienced as well as providing the challenge of unfamiliar geographical areas. In the Air Photo Interpretation module both vertical and oblique aerial photographs at a range of different scales are used. Landsat TM images as well as SPOT panchromatic 10 metre resolution and SPOT-XS, 20 metre resolution data are used in the Multispectral Scanner Interpretation module. Unfortunately the images as they appear on the screen are not as clear as they would appear on an image analysis screen. They seem to have lost resolution in the translation to the program.

I felt there was a little unevenness in the approach to Digital Image Analysis module. Whilst ratios and difference images are well done, image enhancement and spatial filtering are only briefly covered. This medium would be excellent for displaying how spatial filters work on pixels, lines and over whole regions.

I have used these modules in a second year introduction to remote sensing course over the last two years and have found that they are best used as an adjunct to lectures, to revise and back-up lecture materials. I program one supervised practical session using the units. Students then complete and revise the units in their own time. The students reaction to the use of these modules has been enthusiastic. There have been many positive comments on the ease of use, the interesting graphics, the interface and how the program has assisted understanding of some of the more difficult concepts. In 1995, 63 students responded to an evaluation questionnaire. The results of questions about the RSCAL software found that very few students have found difficulty in the use of these CAL modules.

The RSCAL units are an excellent resource for teaching introductory remote sensing. We use the Air Photo Interpretation module for first year Geography students and the other three modules in the second year Remote Sensing of Environment course. Student reaction has been very positive when initially introduced to the modules. They have fun using them and learn quickly. There has also been heavy use of the modules for revision before the final exams. I highly recommend these innovative learning modules for undergraduate remote sensing courses.

Toni O'Neill


Module 1 - What is Remote Sensing? Module 2 - Spectral Signatures
* The Science of Remote Sensing * Introduction
* Data Capture and Analysis * What is a Spectral Signature?
* Remote Sensing Information Types * Identifying Vegetation, Soil and Water
* Passive and Active Remote Sensing * Spectral Characteristics of vegetation
* Scanner and Camera Systems * Spectral Characteristics of Soil
* Physical Processes of Remote Sensing * Spectral Characteristics of Water
* Energy, Space and Time in Remote Sensing * Applications of Remotely Sensed Data
Module 3 - Air Photo Interpretation Module 4 - Multispectral Scanner Interpretation
* The Air Photo * The Multispectral Scanner
* Air Photo Annotation * Scanner Platforms
* Simple measurements from Air Photos * Image Annotation
* Radial Displacement * Image Interpretation
* Air Photo Interpretation Clues * Digital Image Processing

Requirements: PC running DOS, VGA graphics, colour monitor, mouse and 5MB free HD space.

Authors: Australian Key Centre for Land Information Systems (AKCLIS) and the University of Queensland, Computer Assisted Learning Unit. Edited by Dr Gail Kelly and Professor Greg Hill.

Distributor: AKCLIS c/o Dept of Geographical Sciences and Planning, University of Queensland, Brisbane Qld 4072 Fax: (07) 3365 6899

email: g.kelly@mailbox.uq.oz.au

Cost: $185 (site licence by negotiation).