Application potential of SPOT imagery for topographic mapping

The high resolution and good geometric configuration possible with SPOT gives a high potential for the production of 1:100 000 topographic maps. Studies at University College London have investigated this potential with the aid of a simple instrument which will introduce the necessary corrections to level 1b photographic images and orthophotographs and allow stereoscopic viewing of SPOT images and the ability to compile a line map. Accuracy has been investigated by computing ground co-ordinates from image co-ordinates and pixel positions. The methods used and results obtained in this work are described.Work is now going on to investigate the use of digital image processors in the mapping procedures and the use of analytical plotting instruments, and comments on this work and on future developments are made.     

SAMBO-GEOS: On three-dimensional substorm dynamics — A case study for 4 March 1979

For investigations of the isolated magnetospheric substorm the ground-based and satellite geophysical data are discussed. The active phase of the substorm has two parts: an active-convective phase and a classical active phase. The analysed data show that the breakup of the substorm takes place at closed and not very much stretched magnetic field lines.     

Tissue responses to low protracted doses of high LET radiations or photons: early and late damage relevant to radio-protective countermeasures.

Early and late murine tissue responses to single or fractionated low doses of heavy charged particles, fission-spectrum neutrons or gamma rays are considered. Damage to the hematopoietic system is emphasized, but results on acute lethality, host response to challenge with transplanted leukemia cells and life-shortening are presented. Low dose rates per fraction were used in some neutron experiments. Split-dose lethality studies (LD 50/30) with fission neutrons indicated greater accumulation of injury during a 9 fraction course (over 17 days) than was the case for gamma-radiation. When total doses of 96 or 247 cGy of neutrons or gamma rays were given as a single dose or in 9 fractions, a significant sparing effect on femur CFU-S depression was observed for both radiation qualities during the first 11 days, but there was not an earlier return to normal with dose fractionation. During the 9 fraction sequence, a significant sparing effect of low dose rate on CFU-S depression was observed in both neutron and gamma-irradiated mice. CFU-S content at the end of the fractionation sequence did not correlate with measured LD 50/30. Sustained depression of femur and spleen CFU-S and a significant thrombocytopenia were observed when a total neutron dose of 240 cGy was given in 72 fractions over 24 weeks at low dose rates. The temporal aspects of CFU-S repopulation were different after a single versus fractionated neutron doses. The sustained reduction in the size of the CFU-S population was accompanied by an increase in the fraction in DNA synthesis. The proliferation characteristics and effects of age were different for radial CFU-S population closely associated with bone, compared with the axial population that can be readily aspirated from the femur. In aged irradiated animals, the CFU-S proliferation/redistribution response to typhoid vaccine showed both an age and radiation effect. After high single doses of neutrons or gamma rays, a significant age- and radiation-related deficiency in host defense mechanisms was detected by a shorter mean survival time following challenge with transplantable leukemia cells. Comparison of dose-response curves for life shortening after irradiation with fission-spectrum neutrons or high energy silicon particles indicated high initial slopes for both radiation qualities at low doses, but for higher doses of silicon, the effect per Gy decreased to a value similar to that for gamma rays. The two component life-shortening curve for silicon particles has implications for the potential efficacy of radioprotectants. Recent studies on protection against early and late effects by aminothiols, prostaglandins, and other compounds are discussed.     

Biological UV dosimeters in simulated space conditions.

Polycrystalline uracil thin layers participate in the phage and uracil response (PUR) experiment, assigned to the biological dosimetry of the extraterrestrial solar radiation on the International Space Station (ISS). In ground based experiments (experiment verification tests), the following space parameters were simulated and studied: temperature, vacuum and short wavelength UV (UV-C, down to 200 nm) radiation. The closed uracil samples proved to be vacuum-tight for 7 days. In the tested temperature range (from -20 to +40 degrees C) the uracil samples are stable. The kinetic of dimer formation (dimerization) and reversion (monomerization) of uracil dimers due to short wavelength UV radiation was detected, the monomerization efficiency of the polychromatic deuterium lamp is higher than that of the germicidal lamp. A mathematical model describing the kinetic of monomerization-dimerization was constructed. Under the influence of UV radiation the dimerization-monomerization reactions occur simultaneously, thus the additivity law of the effect of the various wavelengths is not applicable.     

An improved Green's function for ion beam transport.

Ion beam transport theory allows testing of material transmission properties in the laboratory environment generated by particle accelerators. This is a necessary step in materials development and evaluation for space use. The approximations used in solving the Boltzmann transport equation for the space setting are often not sufficient for laboratory work and those issues are the main emphasis of the present work. In consequence, an analytic solution of the linear Boltzmann equation is pursued in the form of a Green's function allowing flexibility in application to a broad range of boundary value problems. It has been established that simple solutions can be found for high charge and energy (HZE) ions by ignoring nuclear energy downshifts and dispersion. Such solutions were found to be supported by experimental evidence with HZE ion beams when multiple scattering was added. Lacking from the prior solutions were range and energy straggling and energy downshift with dispersion associated with nuclear events. Recently, we have found global solutions including these effects providing a broader class of HZE ion solutions.     

The MELISSA pilot plant facility as as integration test-bed for advanced life support systems.

The different advances in the Micro Ecological Life Support System Alternative project (MELISSA), fostered and coordinated by the European Space Agency, as well as in other associated technologies, are integrated and demonstrated in the MELISSA Pilot Plant laboratory. During the first period of operation, the definition of the different compartments at an individual basis has been achieved, and the complete facility is being re-designed to face a new period of integration of all these compartments. The final objective is to demonstrate the potentiality of biological systems such as MELISSA as life support systems. The facility will also serve as a test bed to study the robustness and stability of the continuous operation of a complex biological system. This includes testing of the associated instrumentation and control for a safe operation, characterization of the chemical and microbial safety of the system, as well as tracking the genetic stability of the microbial strains used. The new period is envisaged as a contribution to the further development of more complete biological life support systems for long-term manned missions, that should be better defined from the knowledge to be gained from this integration phase. This contribution summarizes the current status of the Pilot Plant and the planned steps for the new period.     

Cloudiness over the Eastern Equatorial Pacific for summer 1983 from geostationary satellite data

The extraordinary El-Nino event of 1982–83 started to fade out in the late spring of 1983. However the sea surface temperature of the Eastern Equatorial Pacific still remained warmer than normal in the following summer. To investigate the characteristics of this late transition phase of the 1982–83 El-Nino, the GOES-West satellite data of July and August of 1983 are analyzed. The outgoing longwave radiation field and the distribution of cloudiness, which was derived by using a new threshold technique, are obtained. The longwave radiation field is compared to monthly average climatic indices commonly used at the Climatic Analysis Center. The results of cloud analysis showed some interesting features during the decaying phase of the 1982–83 El-Nino. The diurnal variation of cloudiness indicates that total cloud amounts decrease from 8 GMT to 20 GMT over most of the area. This overall study demonstrates preliminary results of the International Satellite Cloud Climatology Project of the World Climate Research Program.     

Human Factors R&D Requirements for Future Aerospace Cockpit Systems

Cockpits are rapidly changing from dedicated instruments to multifunction displays, integrated controls, and computer controlled subsystems. Solid-state displays, voice recognition, and artificial intelligence are just a few of the emerging technologies that will help the pilot perform his mission in the future. Early investigations involving mission analysis, sensor data, software development, and evaluations will be required to insure total integration. These new technologies will require extensive human factors research in the areas of anthropometry, displays, controls, human/computer interface, automation, and workload assessment to support the integration process. This research will help provide weapons systems that have increased survivability and reduced pilot workload. This paper addresses some of the human factors research that will be needed to help develop future cockpit systems. It also reviews the basic evolution of the crew station and some of the emerging technologies that will drive human factors research in the 1990s. In the past, crew systems were designed to provide each aircraft function with a corresponding instrument display, such as airspeed indicator, altimeter, attitude direction indicator, vertical velocity indicator, etc. The bulk of the information had to be integrated by the pilot. Present systems are in a state of transition. We are rapidly moving from individual instruments to multifunction displays. The C-17, HH-60, F-15E, B-1B, F-111D, and F-16C/D aircraft use multifunction, cathode-ray tube displays, some of which are color. Another trend is the continued increase in the use of integrated controls.     

Chemical protection against ionizing radiation.

Some of the problems related to chemical protection against ionizing radiation are discussed with emphasis on: definition, classification, degree of protection, mechanisms of action and toxicity. Results on the biological response modifyers (BRMs) and on the combination of nontoxic (i.e. low) doses of sulphydryl radioprotectors and BRMs are presented.