Photogrammetria最新文献

A microlight aircraft has been used to obtain and record concurrent, near-continuous, spectral responses in the MSS and SPOT bands over various ground features. The experiment was performed in Mali, along the Niger river, during November, 1985. The airborne instrumentation, developed as a prototype for this experiment, also included flying-height measurements by a laser range-finder and a colour video-camera. Spectral data and flying height (5 to 80 m) were scanned every 0.1 s and recorded on the audio channel of a videotape, after multiplexing and analogue to digital conversion (8 channels).

The following conclusions were made:

• 1.

  - the measuring and recording system, although light and simple, proved to be very efficient for automatic survey in a tropical environment;

• 2.

  - spectral reflectance profiles are feasible in a very short time over a wide range of objects;

• 3.

  - height measurements can provide very useful information for the geometric description of the vegetation cover;

• 4.

  - microlight aircraft are proving to be highly suitable as platforms for low-cost aerial survey including large-scale photography and complementary to conventional methods.

The ailing African economy for the past fifteen years was analyzed and stressed in some great detail. Limited application of science and the low level of technology were given among the root causes of Africa's economic backwardness. Lack information and data on African member States' natural endowments continue to impede the rate of development of those resources and have tended to bedevil the attainment of the principles of self-reliance, self-sufficiency and self-sustainment. Remote Sensing as a tool to close the information and data hiatus required for rational planning and development, and control of the environment received a great attention. References were made to sub-regional and regional technical co-operation ventures aimed at paving the way for provision of adequate, timely and reliable data for planning. In particular, the ECA -sponsored Regional Training Centres were seen as vehicles for realizing those goals.

The paper presents Soviet experience with aerospace monitoring of ecosystem dynamics based on a comparison of repeated aerial and/or space images. The dynamics of single ecosystems are described by linear or, more commonly, non-linear exponential or parabolic functions. The dynamics of simple two-component ecosystems are described by the interrelation of “reserve” vs. “resource” trends. The dynamics of composite ecosytems are represented by transition matrices and graphs of transition probabilities, using Markovian chains. Provided the areal dimensions and identification accuracy are sufficient, a normative long-term forecast may be calculated for 5–20 years ahead.

The transfer of Landsat-related remote sensing technology from the United States to developing countries was examined in this research. A survey of experts in the field of remote sensing technology was conducted to determine what they perceived as the major obstacles to remote sensing technology transfer (RSTT). Useable questionnaire responses were received from 666 professionals in 66 countries. Responses of participants representing developed countries, developing countries, and international organizations were compared in order to identify similarities and differences in their perceptions of the RSTT obstacles. In addition to examination of individual questionnaire items, the data were analyzed further to reveal underlying issues that must be recognized and addressed if remote sensing technology is to be successfully applied to development activities.