(3) On the Block Adjustment of Aerial Triangulation 
by Shohachi Kurihara 
Hiroshi Asada 
We, representatives from 4 orgäni zations took part the experimental works 
of Block Adjustment of Comm.III, 1.5.P. and have sent the report to the chief of 
the Working Group. 
5-4 Coramission IV 
The main topics in the field of Commissio 
which are related to large scale mapping, 
applications to civil engineering. 
5-4-1 Large scale mapping 
n IV in Japan were three projects 
orthophoto projects and photogrammetric 
The project team of the large scale mapping for applying the land readjustment L 
works was organized with the specialists from the 8 private companies under the 
direction of Mr. Takiyama, Managing Director of Toyo Koku Jigyo Co. Ltd. 
The result of photogrammetry ( photo scale : 1/3, 000 ) 
the coordinates gained by the geodetic survey. The plane, 
were checked on the 1 : 500 mapping sheet. 
was compared with 
height and area accuracy 
The accuracy of plane was 0.1 mm in 
mean value, 0. 2 mm in max.value on the mapping sheet and the accuracy of height 
was 2.0 cm in mean and 12 cm in max.value. 
This research is to be continued 
to check more precisely on the criterion of the large scale mapping. 
5-4-2 Orthophoto projects 
The cooperative wórks of orthophoto supported by 10 private companies has 
started in December of 1970. 
- 14 - 
(e 
tw 
th 
ec