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erly are exploited by the educator, they could create strong 
motives to the student who will try to find out how this happens. 
So the learning process takes a Bottom-Top-Bottom (BTB) approach 
instead of a top to bottom which is the conventional way of teach 
ing process. The course material so is organized as usual into 
individual modules or sections and each section dealing with a 
specific problem, then the BTB approach is applied to that section 
as follows: The instructor demonstrates the solution of the prob 
lem using a binary coded version of a program which has been writ 
ten before by him or her and allows the students to have access of 
execution only. The students can process real data and obtain pro 
duction results. Then a lab exercise is given to the students to 
write a computer program to do the same thing. The instructor may 
provide the source code of several routines or may provide, with 
certain restrictions, the source code listing of the entire pro 
gram, so that the average student will finish the assignment 
within the expected time limits. The lecture then covers the theo 
retical aspects of the problem in an optimum algorithm form making 
it easy for the students to understand because they are practicing 
at the same time on how to implement the algorithm. The lecture 
does not have to enter into a great depth of the theory leaving 
that option to any interested student who wants to study further 
from provided references. In this way there is an integrated learn 
ing process of all components involved: theory (at any depth), 
algorithm, software, hardware plus that the student is confident 
of knowing the content of the study section. This learning process 
was applied first during my nine year career at the Surveying 
Engineering Program of the California State University, Fresno and 
provided excellent results (Hatzopoulos J.N. 1985). 
In the Department of Environmental Studies, of the University of 
the Aegean, the same process is also applied for remote sensing 
and GIS courses. There is a microcomputer laboratory with PC com 
patible microcomputers having CGA and Hercules graphics cards. 
This lab is used for both remote sensing lab assignments and GIS 
lab assignments. Two examples one in remote sensing and one in GIS 
of lab assignments are given bellow: 
Remote Sensing Lab assignment 9. RADIOMETRIC ENHANCEMENT 
A part of landsat image of channel 4 is composed of 90 lines by 
150 columns and it is available in the file LAB9.DAT. Write a com 
puter program to do the following: 
1. Generate 10 gray scale shades by making a hyperpixel composed 
of 3x3 = 9 single pixels of the PC-CGA graphics card which will be 
worked in monochrome high resolution graphics mode. 
2. Read the available file LAB9.DAT one line at a time and hold 
in memory those values needed to create the regular histogram of 
the digital image and the equalized histogram. 
3. Create a menu within the program which allows the following 
operations for radiometric enhancement and image display: 
(a) Display regular histogram.