institutions and organisation in our country 
makes the adequate use of this recordings even 
more difficult: 
- The lack of standardisation, and the 
incompatibity between existing hard & soft 
systems of remote sensing (some of them quite 
sophisticated and performant) hinder the 
working in multi & interdisciplinary system-so 
needed in this domain cannot be achieved: 
- So, our reentrance in Europe and in the 
World takes real sacrifices from us; but we like 
to express our wish and intentions not to lose 
touch with the advanced and top technologies. 
2. OUR INTEREST AND SPECIFIC 
OBJECTIVES 
Basic and guiding ideas for treating and solving 
complex problems by remote sensing refere to: 
(a) establishing the specific strict necessary 
needs of users at territorial, regional and local 
level, by priorities, hierarchly, by importance 
and urgence reasons; 
(b) the focusing of interest and efforts on the 
terrestrial segment of the chain of remote 
sensing processing and generally of the 
available systems we have, as well as to reduce 
to a minimum point (strictly necessary) of the 
number of satellite recordings for the purposed 
thematic; 
(c) hierarchly use of the ways of data 
processing methods and analysis, analogical, 
hybrid and digital strictly necessary, with 
effective integration of endo and exogene 
parameters offering the approach of the 
problem their relative or/and absolute 
compatibilisation (reference system, calibration 
— registration - synergism, etc.); 
(d) the technology transfer ways serie directly 
to the users is closely and continuously 
watched, as step by step this verified and tested 
technology can be properly launched; 
(e) usually, we achieve the ground sampling 
with panchromatic and sometime with colour 
IR aerophotogramms due to the very difficult 
field condition. 
The start of our research begin with the 
agreement with NASA  (G-27940/1972, 
Oprescu a) for natural resources investigation 
and monitoring of them, in the lower Basin of 
Danube and Danube Delta. 
We must mention that, there are many studies in 
different zones not specific for remote sensing 
which are very usefull for sampling and to 
determine the accuracy of the results. 
About the test site: 
- The Danube Delta is one of Europe’s most 
extensive wetlands in a natural state, it forms a 
unique series of interrelated ecosystems, with 
its large reed beds, maze of with their mosaic of 
forests and semi-arid grasslands; the Delta 
ecosystems cover about 564.000 ha; of this 
442.000 ha lie within Romania; 
- The Danube Delta and the coastal zone of 
the Black Sea represents areas of high scientific 
interest; the Danube Delta represents the 
world’s larges surface compactly coveres with 
rush (reed); this interest grew becouse the 
Danube Delta was declared in 1990 a natural 
reservation of the Biosphere. 
3. THE METHODOLOGY FOR CONCEI- 
VING THIS PROJECT AND IMPLEMEN- 
TATION OF THE PROPOSED THEME. 
3.1.The Data-base with index recordings. 
Now we have a lot of different remote sensing 
missions with RADAR or multispectral on- 
board sensors. For each of them we know, more 
or less, the covering mode. But, for one future 
moment, we couldn’t say if it is possible to 
obtain a remote sensing recording. 
For this reason, we need a Data-base with future 
recordings, including all active remote sensing 
missions from which we could ask, for a certain 
moment, an aero or a satellite remote sensing 
recording. 
For building a such Data-base we need to 
compute the accurate intermediary orbites for 
the remote sensing satellite and to establish on 
this base, the covering in time, of interested 
zones. 
In the same time, because the initial orbital 
elements are changed, one must obtain the 
actual values of them (the Iszac’s elements - 
Vinti 1961), by processing astronomical 
satellite observations made upon a 
determinated number of satellite revolutions. 
After computing these satellite orbites, taking 
into acount: 
= the central point of the remote sensing 
image; 
= the covered area of the image; 
= the time between two succesive recordings; 
= the interested zones 
we will obtain the remote sensing images that 
are possible to record, and if some program ask 
  
  
  
  
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