Prof. Doré, Italy, declared that: »La SIP doit s’occuper des problèmes
importants mentionnés par Dr. Wassef. Il faut vaincre les difficultés d’ordre
psychologique qui ont leur origine dans la distinction traditionelle entre erreurs
accidentelles, considérées comme variables, et d’une distribution normale, et
les erreurs systématiques. Le travail préalable est toujours l’analyse statistique
préconisée par Dr. Wassef.»
The ISP should consider the problems brought up by Dr. Wassef. The traditional distinction
between accidental errors, considered as variables, and systematic errors, gives rises to difficulties
of a psychological nature, that must be overcome. The preliminary work is always the statistical
analysis recommended by Dr. Wassef.
Dr. Wassef: »Prof. Hallert mentioned that much of the statistical procedure
is given in Jordan-Eggert, but I think there has been great development in
statistical methods in the passed 10 or 20 years that probably are not included
in Jordan-Eggert. Regarding the use of the method of least squares for adjust
ment I think I agree fully with Prof. Hallert that it can only be used after we
have made an analysis of the error to find out whether the method of least
squares depends on the pure accidental error and is applicable to whatever we
are going to adjust.
Les méthodes statistiques ont certainement subi une forte évolution pendant les dernières 10—20
années, et tous les éléments nouveaux ne se trouvent pas dans l’oeuvre citée par M. Hallert. Il est
vrai que la méthode des moindres carrés ne doit être appliquée qu’après analyse de l’erreur.
Miss N. Sokolova, U.S.S.R., was requested to deliver the second report from N. Sokolova:
the delegation of the USSR, entitled: »Photogrammetric works in USSR».
The photogrammetrists of the USSR use pictures taken in various scales by
cameras equipped with wide and super-wide angle lenses. The work is performed
by means of home-produced instruments designed to perform a whole process
(in Russian called universal-instruments) and the differential ones.
At present the aerotriangulation is performed by means of such instruments
as the multiplex and the stereoprojector SPR of Prof .-Dr. Romano vsky. The
projectors of our multiplexes have angles of view such as: 64°, 100° and 122°.
The size of slides to be put in the projectors is G X 6 cm. The stereo-projector
of Prof. Romanovsky is a new stereophotogrammetrical instrument with a high
degree of accuracy. Its construction is based on the principles of affine projec
tion. This instrument enables us to work with photographs of any angle value.
The instrumental error of SPR is 1: 10 000 of the flight-height.
There is another method of aerotriangulation practised in USSR. It is an
analytical method called the Method of a Nondistortioned Model. For adjust
ment of aerotriangulation nets the airborne elements of exterior orientation are
used. In some cases of aero-radio-levelling, in order to increase the number of
control points, a method of »Folgebildanschluss» is performed by means of the
stereometer of Prof. Drobishev.
For horizontal control there are such methods as photopolygonometry and
graphical radial-triangulation. The method of photopolygonometry is based on
the combination of photogrammetrical measurements of angles formed by the
base lines and of lengths of bases. The latter task is performed by aid of the
airborne readings of the radio-altimeter RWTD.
By the differential method of map compilation the process of contour
drawing and the process of map-compilation are separated. The basic instrument
for contour-drawing is the topographical stereometer of Drobishev. It has
special devices for the automatic correction of horizontal parallaxes.
The topographical stereometer has a large field of view and allows the
operator to see the stereoscopic model of the terrain and the drawn contour
simultaneously. Therefore it is very convenient for contour-drawing in flat
and wooded countries.
The instrumental error of the topographical stereometer is H/6 000.
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