Level Crossing Rate of Macrodiversity System in the Presence of Multipath Fading and Shadowing

Macrodiversity system including macrodiversity SC receiver and two microdiversity SC receivers is considered in this paper. Received signal experiences, simultaneously, both, long term fading and short term fading. Microdiversity SC receivers reduces Rayleigh fading effects on system performance and macrodiversity SC receiver mitigate Gamma shadowing effects on system performance. Closed form expressions for level crossing rate of microdiversity SC receivers output signals envelopes are calculated. This expression is used for evaluation of level crossing rate of macrodiversity SC receiver output signal envelope. Numerical expressions are illustrated to show the influence of Gamma shadowing severity on level crossing rate

SOIL EROSION EVALUATION IN THE RASTOCKI POTOK WATERSHED OF MONTENEGRO USING THE EROSION POTENTIAL METHOD

Soil erosion is the most important factor of land degradation worldwide, causing significant environmental problems in the region of South East Europe also. We studied soil erosion processes in the RastockiPotok Watershed of Montenegro using the Erosion Potential Method (EPM) of Gavrilovic, which is created in Yugoslavia and is the most suitable on catchment level for the watershed management needs in this Region. The peak discharge (Qmax) is calculated on 150 m3s-1 and there is a possibility for large flood waves to appear in the studied basin. According to our analysis, the coefficient fs, (portion under forest) is 0.45; ft (grass) is 0.41 and fg (bare land) is 0.14 and the coefficient of the river basin planning, Xa, is 0.52. Real soil losses, Gyr, were calculated on 1472m3yr-1, specific 250m3km-2yr-1. The value of the Z coefficient of 0.488 indicates that the studied watershed belongs in the Destruction Category III: the erosion process is medium. This study confirmed the findings of the other Balkan researchers that the EPM method of Professor Gavrilovic is a useful tool for calculating sediment yield in the South East Europe

Ameliorative, Ecological and Landscape Roles of Făget Forest, Cluj-Napoca, Romania, and Possibilities of Avoiding Risks Based on GIS Landslide Susceptibility Map

In the case of forests located in the close proximity of urban centres, the functions and conventional roles of the forests have to be largely reconsidered. An experimental study area was located in Făget Forest, near the city of Cluj-Napoca, North-West of Romania, as a subject to evaluate different natural risks, especially landslides. Although most of this area is stabilized, human activity became in the last period the most aggressive and active factor that can induce changes in slopes stability. The evaluation based on new changes on the terrain and constructions has clearly revealed the effect of the unprecedented urban sprawl and the expansion of infrastructure elements and residential buildings. Landslide susceptibility map was elaborated using a multivariate statistical analysis and the Geographical Information System (GIS) technology on a predetermined path inside the forest, as well as obtaining valuable information about the tree species. Based on 14 surveys, each of them covering an area of 500 m2 on a longitudinal transect of the forest, there were identified relatively few tree species with a significant share: Carpinus betulus (42.9%), Fagus sylvatica (24.9%), Quercus petraea (23.2%), Q. robur (6.3%), Prunus avium (1.2%). Their positive roles on avoiding or limiting the flow on slopes, flooding, landslides etc. are different depending on the position, terrain, forest composition, trees density, slope, exposition, but it is fundamental beneficial. However, these species can assure productive (as wood), ameliorative, ecological, landscape, cultural, educational, relaxation roles, and consequently inestimable values

Monotonicity of the error term in Gauss-Turán quadratures for analytic functions

For Gauss¿Tur¿an quadrature formulae with an even weight function on the interval [-1; 1] and functions analytic in regions of the complex plane which contain in their interiors a circle of radius greater than 1, the error term is investigated. In some particular cases we prove that the error decreases monotonically to zero. Also, for certain more general cases, we illustrate how to check numerically if this property holds. Some `2-error estimates are considered

Assessment of soil erosion in the Lipnica watershed, Polimije, Montenegro

Assessment of soil erosion risk is of great importance for management of natural resources, allowing decision makers to modify land use properly implementing environmental strategies more sustainable in the long-term. Inappropriate land use and land management is often viewed as main cause of accelerated erosion rates. Modelling soil erosion rates is key to understand the impact of future land management and climate change on land degradation. Polimlje is one of five river basins in Montenegro that drains toward the Danube and is divided into fifty-seven sub basins. Lipnica watershed is one of them where we studied soil erosion processes using the IntErO model, with the Erosion Potential Method embedded in the algorithm of this computer-graphic method. For the current state of land use, calculated maximal outflow from the river basin is 58 m3s-1 for the incidence of 100 years and the net soil loss is 469 m³year-1, specific 92 m³ year-1 per square kilometre. With the results obtained we were able to conclude that the river basin belongs in „Destruction Category V”, according to the classification system of Gavrilovic; the erosion process is very weak. This study has shown that the IntErO model and Erosion Potential Method are useful tools for researchers in calculation of sediment yield at the level of the river basins for the South East European regio