Analysis of GPS and Loran-C performance for land vehicle navigationin the Canadian Rockies

Loran-C and GPS were assessed for vehicular navigation along selected roads of British Columbia during the winter of 1991. The general topography of this mountainous area is described, together with the specific topographic features and tree coverage characteristics of the 2000 km of roads tested on the mainland and on Vancouver Island. The configuration and characteristics of the Loran C Canadian West Coast chain along the roads used are described. The portable vehicle-mounted system used to collect and analyze the Loran-C and GPS signals along road profiles is described. The performance of Loran-C is analyzed in terms of signal to noise ratios (SNR), field strength, and time-difference distortions, as measured by differential GPS. These distortions, which can reach several hundred meters over distances of less than 20 km, are analyzed in terms of topographic features. The possibility of using these time-independent distortions to calibrate Loran-C for use along the above roads is discussed. Masking of GPS signals due to topographic features and tree coverage along the roads is analyzed. A comparative analysis of both Loran-C and GPS is presented in terms of signal availability and accuracy     

Reduced lymphocyte activation in space: role of cell-substratum interactions.

We investigated the effect of substratum adhesiveness on stimulated lymphocyte blastogenesis by reducing and blocking cell adhesion with poly (2-hydroxyethyl methacrylate) (poly-HEMA) in a simple on-ground system. Cells grown on medium-thick and thick poly-HEMA films were rounded in shape and displayed no signs of spreading. By contrast, on tissue culture plastic and very thin poly-HEMA films, they showed clear signs of spreading. The mitogenic response of lymphocytes grown on thick poly-HEMA films was reduced by up to 68% of the control (tissue culture plastic). Interferon-gamma production was near zero when the cells were grown on the least adhesive substratum. On uncoated plastic, activated lymphocytes subjected to high gravity (20g) exhibited an increased proliferation rate (40%) compared with 1g. By contrast, on poly-HEMA, high gravity did not improve lymphocyte responsiveness. These results show that activated lymphocytes need to anchor and spread prior to achieving an optimal proliferation response. We conclude that decreased lymphocyte adhesion could contribute to the depressed in vitro lymphocyte responsiveness found in the microgravity conditions of space flight.     

The γ-ray bursts as a result of the proper activity of the neutron star

The model of the Γ-ray burst is developed which is based on the nuclear explosion in the neutron star envelope because of the chain fission reaction of the superheavy nuclei. It is shown, that the main part of the Γ-ray burst radiation must have thermal origin, but the nonthermal component and Γ-ray lines may be present. The parameters of the strong burst of 5 March 1979 are evaluated on the basis of its radiation spectra and the present model. The distance to this burst is about 100 pc and the total energy of this Γ-ray burst is about 2.1039 ergs.     

Instrumentenentwicklungen für anwendungsaufgaben der fernerkundung photogrammetrie,geophysik und geodäsie

(Instrument Developments for Applications in Remote Sensing, Photogrammetry, Geophysics and Geodesy) The Modular Optoelectronic Multispectral Seanner MOMS-01, a CCD camera using the push-broom scanner principle, is presented in this paper in its flight configuration. This instrument will be the first European-built spaceborne unaging system for remote sensing applications (launch with Shuttle flight No. 7).Follow-on developments of this initial two-channel version are oriented to an extension of capabilities by a panchromatic high-resolution stereoscopic module for thematic mapping and two additional spectral channels in the reflective IR (up to 2.3 μm) offering a high interpretation potential for future earth resources exploration missions. Furthermore the subjects of advanced laser technology studies are introduced: A picosecond pulse laser system for detection of tectonic motions and for geodetic application, a CO laser for ultra precise range rate determination (Earth potential and Geoid) and a laser range finder for intersatellite distance measurements.     

The statistical properties of coronal mass ejections during 1979–1981

The Solwind coronagraph on the P78-1 earth-orbiting satellite has been monitoring the Sun routinely at 10-minute intervals during the 5-year interval from April, 1979 to the present. In a statistical analysis of about 1000 mass ejections observed through the end of 1981, we find an average occurrence rate of 1.8 mass ejections per day. Histograms of speed, central latitude, angular span, brightness, and other parameters have been constructed, and properties such as shape classification have been tabulated. These characteristics are summarized for these years near sunspot maximum. The average speed and mass estimate are found to be similar to those found at the declining phase of the previous sunspot cycle. The angular span and central latitude distributions are quite different than seen during the declining phase, and are very dependent upon structural class. The fluctuations in the occurrence rate of CMEs does not seem to match the fluctuations in the sunspot number. There is a tendency for high speed CMEs to occur more frequently in 1981 than in 1980, and more frequently in 1980 than in 1979.     

Microbial utilisation of natural organic wastes

The waste management strategy for the future should meet the benefits of humanity safety, respect principals of planet ecology, and compatibility with other habitability systems. For these purpose the waste management technologies, relevant to application of the biodegradation properties of bacteria are of great value. The biological treatment method is based upon the biodegradation of organic substances by various microorganisms. The advantage of the biodegradation waste management in general: it allows to diminish the volume of organic wastes, the biological hazard of the wastes is controlled, and this system may be compatible with the other systems. The objectives of our study were: to evaluate effectiveness of microbial biodegradation of non-pretreated substrate, to construct phneumoautomatic digester for organic wastes biodegradation, and to study microbial characteristics of active sludge samples used as inoculi in biodegradation experiment. The technology of vegetable wastes treatment was elaborated in IBMP and BMSTU. For this purpose the special unit was created where the degradation process is activated by enforced reinvention of portions of elaborated biogas into digester. This technology allows to save energy normally used for electromechanical agitation and to create optimal environment for anaerobic bacteria growth. The investigations were performed on waste simulator, which imitates physical and chemical content of food wastes calculated basing on the data on food wastes of moderate Russian city. The volume of created experimental sample of digester is 40 l. The basic system elements of device are digesters, gas receiver, remover of drops and valve monitoring and thermal control system. In our testing we used natural food wastes to measure basic parameters and time of biodegradation process. The diminution rate of organic gained 76% from initial mass taking part within 9 days of fermentation. The biogas production achieved 46 l per 1 kg of substrate. The microbial studies of biodegradation process revealed following peculiarities: (i) gradual quantitative increasing of Lactobacillus sp. (from 10(3) to 10(5) colony forming units (CFU) per ml), (ii) activation of Clostridia sp. (from 10(2) to 10(4)CFU/ml), (iii) elimination of aerobic conventional pathogens (Enterobacteriaceae sp., Protea sp., staphylococci). The obtained results allow to evaluate effectiveness of proposed technology and to determine the leading role of lactobacilli and clostridia in process of natural wastes biodegradation. Our further investigations shall further be concentrated on creation of artificial inoculi for launching of food wastes biodegradation. These inoculi will include active and adapted strains of clostridia and lactobacilli.     

Daytime VHF amplitude scintillations recorded at an Indian low-latitude station,Waltair (17.7°N, 83.3°E) during 1997–2003

In this research, it is presented the daytime amplitude scintillations recorded at VHF frequency (244 MHz) at an Indian low-latitude station, Waltair (17.7°N, 83.3°E) during seven continuous years (1997–2003). Contrary to the nighttime scintillation seasonal trends, the occurrence of daytime scintillations maximizes during summer followed by winter and the equinox seasons. The fade depths, scintillation indices and the patch durations of daytime scintillations are meager when compared with their nighttime counterparts. A co-located digital high frequency (HF) ionosonde radar confirms the presence of sporadic (Es) layers when daytime scintillations are observed. The presence of daytime scintillations is evident when the critical frequency of the Es-layer (foEs) is ≥4 MHz and Es-layers are characterized by a highly diffuse range spread Es echoes as can be seen on ionograms. It is surmised that the gradient drift instability (GDI) seems to be the possible mechanism for the generation of these daytime scintillations. It is quite likely that the spread Es-F-layer coupling is done through polarization electric fields (Ep) that develop inside the destabilized patches of sporadic E layers, which are mapped up to the F region along the field lines as to initiate the daytime scintillations through the GDI mechanism. Further, the presence of additional stratification of ionosphere F-layer, popularly known as the F3-layer, is observed on ionograms once the Es-layers and daytime scintillations are ceased.