277 research outputs found

    Factors of land abandonment in mountainous Mediterranean areas : the case of Montenegrin settlements

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    Land use changes have been investigated in the surroundings of 14 rural Montenegrin settlements in order to get specific information about trends in land abandonment since around 1950. Permanently, seasonally and less inhabited settlements with different geographic conditions were studied. This was done by interviewing local inhabitants, which enabled a holistic approach to reveal the underlying processes of land abandonment. According to the observed patterns of land use change, the study sites can be categorized into intensified, urbanized, extensified, overgrown and forested cases. The category of extensified settlements is characterized by a highly reduced agricultural management intensity, resulting in an increase in grasslands and fruit trees at the expense of cropland. This land use change is mainly related to emigrating and aging inhabitants, having less livestock. Such extensive land use is found in both permanently inhabited and abandoned villages. Only some studied settlements became largely overgrown by bushes and forest. The steep average slope gradients and a large distance to the nearest city are explanatory factors of such land abandonment. Land use intensification takes place in low-lying areas located nearby towns

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

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    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

    Performance Analysis of Selection Combining Over Correlated Nakagami-m Fading Channels with Constant Correlation Model for Desired Signal and Cochannel Interference

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    A very efficient technique that reduces fading and channel interference influence is selection diversity based on the signal to interference ratio (SIR). In this pa¬per, system performances of selection combiner (SC) over correlated Nakagami-m channels with constant correlation model are analyzed. Closed-form expressions are obtained for the output SIR probability density function (PDF) and cumulative distribution function (CDF) which is main contribution of this paper. Outage probability and the average error probability for coherent, noncoherent modulation are derived. Numerical results presented in this paper point out the effects of fading severity and cor¬relation on the system performances. The main contribu¬tion of this analysis for multibranch signal combiner is that it has been done for general case of correlated co-channel interference (CCI)

    Testing NDVI, tree cover density and land cover type as fuel indicators in the wildfire spread capacity index (WSCI): case of Montenegro

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    This paper presents an updated version of our previous GIS-based method developed for indexing the forest surfaces by their wildfire ignition probability (WIPI) and wildfire spreading capacity (WSCI). The previous study relied on a multi-criteria approach including a variety of factors of social, hydro-meteorological, and geo-physical character of the context. However, this study is challenging the drawbacks of the previous work, by introducing three new criteria regarding the vegetation properties in the area. Normalized Difference Vegetation Index (NDVI), Tree Cover Density (TCD), and land cover type are launched as indicators of fuel properties of the forest being indexed. The materials and software utilized here belongs to different open sources. CORINE Land Cover (CLC), Open Street Map (OSM), TCD via Copernicus high resolution data, and multispectral satellite images via Landsat 8 (Semi-Automatic Classification Plugin- SCP) are utilized as raw materials in a workflow in QGIS software. At this stage, the study area is the territory of Montenegro. Following the inventory stage, the indexing method relies on a normalizing procedure in QGIS and the assignment of weighted impact factor to each criterion via analytical hierarchy process (AHP). The WSCI value is derived as the sum of the products between the normalized class and the respective weighted impact factor of each criterion. Besides the methodological improvements the results of this work deliver tangible outputs in support of forest fire risk reduction in disaster risk management and fire safety agendas

    Assessment of the capacity for flood monitoring and early warning in Enlargement and Eastern/ Southern Neighbourhood countries of the European Union

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    Flooding is a natural disaster that can damage large areas in the vicinity of rivers, and in the case of flash floods, also in the vicinity of smaller streams. The Global Risks Report 2017 lists extreme weather events, of which flooding is the main risk in most countries, as the risk with the second highest potential impact and the highest likelihood of occurrence. It furthermore seems likely that climate change will aggravate flood impacts in many regions. This report presents an assessment of the capacity for flood monitoring and early flood warning in 17 of the 22 countries which belong to the Eastern and Southern neighbourhood policy of the European Union and the enlargement candidate countries. Many of these receive external funding to improve their systems, but this is often on an ad hoc basis and through individual projects.JRC.E.1-Disaster Risk Managemen

    Production of planting material of raspberry variety glen ample in the North Montenegro

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    The objective of the paper is to present the method of production, quantity, and quality of obtained planting material per unit area of continental fruit within the period of three years (2018-2020), and, in particular, the nursery of raspberry variety Glen Ample in Polimlje, Bijelo Polje municipality, northern Montenegro. The paper shows the initial condition, preparation for the formation of nurseries, production, and quality of raspberry seedlings, which are among the most important berry fruit species grown in northern Montenegro. The production of nurseries was within the limits for the production of raspberry planting material. The number of plants per square metre (m2) at the end of the season was 20.2, and 202,000 per hectare (ha). The height of the seedlings at the end of the vegetation was 1.06 m, and the diameter above the root neck was 9.5 mm. The planting material met the prescribed standards. Based on the standard, seedlings were classified into three classes, and most seedlings of class I (73%) were obtained, followed by class II (24%), while only 3% of seedlings were out of class. Raising raspberry plantations with quality planting material is one of the most important factors for intensifying the production of this type of fruit in Montenegro

    Performance Analysis of 5G Transmission over Fading Channels with Random IG Distributed LOS Components

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    Mathematical modelling of the behavior of the radio propagation at mmWave bands is crucial to the development of transmission and reception algorithms of new 5G systems. In this study we will model 5G propagation in nondeterministic line-of-sight (LOS) conditions, when the random nature of LOS component ratio will be observed as Inverse Gamma (IG) distributed process. Closed-form expressions will be presented for the probability density function (PDF) and cumulative distribution function (CDF) of such random process. Further, closed-form expressions will be provided for important performance measures such as level crossing rate (LCR) and average fade duration (AFD). Capitalizing on proposed expressions, LCR and AFD will be discussed in the function of transmission parameters

    Averaged Nyström interpolants for the solution of Fredholm integral equations of the second kind

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    Fredholm integral equations of the second kind that are defined on a finite or infinite interval arise in many applications. This paper discusses Nyström methods based on Gauss quadrature rules for the solution of such integral equations. It is important to be able to estimate the error in the computed solution, because this allows the choice of an appropriate number of nodes in the Gauss quadrature rule used. This paper explores the application of averaged and weighted averaged Gauss quadrature rules for this purpose and introduces new stability properties of them
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