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  • The analysis of the fair data of a solar energy power plant with SPSS
    60-63
    Views:
    102

    The use of fossil energy sources greatly damages the environment. Moreover, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water and biomass) in energy generation.
    Huge amounts of energy (1100-1300 kWh/m2 per year) arrive at the earth from the sun, and are utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV – panels. This can be fed into a grid. At the University of Debrecen is a solar energy power plant from September 2005 in operation. The electricity performance of the incorporated PV-panels (Kyocera, Dunasolar, and Siemens) are 8.64 kW. The are of PV – panels is 110 square meter. With the aid of the data storage, the tension, current, temperature of the PV-panels, global radiation, air temperature, wind speed, wind direction and the achievement is measured by the ac network.
    The effect of the shading on the performance of the PV – panels and the solar energy power plant is examined. The analysis and the graphic representation of the experiment results are carried out with SPSS per grief. We produced per grief.

  • Daily behaviour of Hungarian Grey Cattle under range grazing conditions
    45-48
    Views:
    169

    Cattle behaviour on rangeland depends on external factors, such as grass allowance and quality, temperature, net solar radiation, distance from water-source, wind speed and direction, air pressure changes and the applied breeding technology. Our research is based on previous empirical observations and modern methods to analyze the behaviour of the Hungarian Grey Cattle. Today it is crucial to use cost-effective solutions in modern beef cattle farming therefore we introduce a cost-efficient method to study and follow cattle herds. We are studying relation between traveled daily distance and air pressure. The various weather fronts influence behavioural characteristics and traveled daily distance. According to our hypothesis, the pressure-change and the wind direction has significant effect on cattle activity on pasture. As the different air masses alter the barometric conditions and unbalance the neuroendocrine system, indirectly cause relaxed or agitated behaviour

  • The use of renewable resources is an opportunity and an obligation
    13-17
    Views:
    103

    The renewable energy sources could be used in energy production, while no or only very slightly emit harmful substances to the environment. The solar, wind, hydropower, biomass and heat rational utilization of land contributes to greenhouse gas emissions.
    Renewable energy sources also reduces the dependence on fossil fuels, thus contributing to increase security of supply. The creation of local jobs to strengthen the area's population retaining ability.

  • The impact of environmental factors on the measurement of the normalized difference vegetation index
    141-147
    Views:
    136

    The level of nitrogen supply of a plant population can be quickly measured with non-destructive optical measurement devices and the differentiated determination of nitrogen shortage and the replenishment of nitrogen can also be carried out. The level of nitrogen supply is based on the fact that the chlorophyll content of crops is in close correlation with nitrogen content and that the amount of chlorophyll can be easily measured on the basis of the light absorption of chlorophyll molecules. The successfulness of optical measurements can be influenced by the change of weather  parameters; therefore, it is important to know the correlations between measurement results and weather parameters when it comes to practical use.
    The GreenSeeker Model 505 measurement device determines the relative chlorophyll content in the form of the Normalized Difference
    Vegetation Index (NDVI) calculated on the basis of the intensity of the reflected red and infrared rays of light from the crop population. The measurements were performed in alfalfa population with 10 replications at five measurement heights and four measurement times. The weather parameters were measured by a weather station located in the middle of the alfalfa population and the correlations between the meteorological data and the NDVI values were examined. During the statistical evaluation of the results, it was established that the NDVI measurement is primarily influenced by the relative humidity of the air, secondly by air temperature and thirdly by wind speed. Relative humidity was in strong correlation with the NDVI values which were also influenced by the measurement height and time. Regression was not significant in the case of 20 cm  measurement height, but the measurements above 40 cm height showed significant correlations. The correlation was shown to be strong at each measurement time, but the influence of humidity was the lowest at 11:00 and 14:00. 

  • Assessment of Environmental Susceptibility/Vulnerability of Soils
    62-74
    Views:
    90

    Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
    The main soil functions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
    Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
    Soil resources are threatened by the following environmental stresses:
    – soil degradation processes;
    – extreme moisture regime;
    – nutrient stresses (deficiency or toxicity);
    – environmental pollution.
    Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
    The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
    The efficient control of these processes necessitates the following consecutive steps:
    • registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
    • evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
    • assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
    • elaboration of efficient technologies for the „best” control alternatives (best management practice).
    Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
    Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
    The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society.

  • Renewable energy resources in the EU (Policy scenario)
    143-146
    Views:
    109

    The use of renewable energies has a long past, even though its share of the total energy use is rather low in European terms. However, the tendencies are definitely favourable which is further strengthened by the dedication of the European Union to sustainable development and combat against climate change. The European Union is on the right track in achieving its goal which is to be able to cover 20% its energy need from renewable energy resources by 2020. The increased use of wind, solar, water, tidal, geothermal and biomass energy will reduce the energy import dependence of the European Union and it will stimulate innovation.

  • Ecological Conditions of Agricultural Land Use in Transcarpathia
    190-194
    Views:
    73

    The unbalanced anthropogenic effects for several decades resulted in significant technogen damages in the ecosystem of Ukraine. Excessive land development, including the use of slopes, effected the disintegration of the natural balance of lands – arable-lands, meadows, forests, and watershed areas – producing quite a negative effect on the landscape’s nature itself. It has to be stressed that according to other indexes, too, agricultural lands show a tendentious deterioration.
    Erosion, caused by water and wind, is one of the most influential factors in the degradation of agricultural soils and in the reduction of the productiveness of benefital lands. Nowadays the degree erosion became significant and it directly endangers the existence of the soil which is a principal chain-link of the agricultural cultivation as well as an irreplaceable element of the biosphere.
    The social and political changes in Ukraine’s life demand fundamental modernization in the land utilization both in ecological and in economical aspects. However, these aims can be realized only if, during the developments, we base on the up-to-date results of agronomics, and we do further research in the relations of agricultural land use and environmental protection. According to the latest theories, rational and environmental-safe agricultural production relates to the optimum correlation of the natural- and agricultural- ecosystems as well as to the reconstruction of agricultural areas built on the basis of environmental protection.

  • The Presentation of Debrecen University’s Solar Energy Power Plant
    259-263
    Views:
    83

    Energy plays an important role in everyday life and in the economy. The use of fossil energy sources greatly damages the environment. Besides this, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water, biomass) in energy generation. Huge amounts of energy (1150-1300 kWh/m2) arrive at the earth from the sun, which utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV-Panels. This can be fed into the grid.

  • Energy use – in terms of efficiency
    61-66
    Views:
    156

    In the recent decades it has become apparent that the human race can lead to a polluting and energy- wasting lifestyle and the depletion of natural resources and an ecological disaster as well.

    Energy efficiency is the realization of the chance to see a wider use of renewable energy. Renewable energy sources can be found in large quantities in Europe. A proper exploitation of these would be important because of the "traditional" energy sources’s sate is very critical in many ways.

    The utilization of renewable energy sources depends on many factors. The local natural conditions significantly determine each country's different renewable energy potentials. I find to be important the natural conditions, such as, solar radiation intensity , the number of sunny days per year, the wind conditions , the volume and their energy characteristics of the geothermal power resources , land features , soil and rock quality, the supply of fossil fuels or the nuclear possibilities of energy production. The economic environment is also a major influencing factor for the utilization of renewables. The conditions of price of fossil fuels (natural gas, oil and coal), the price of nuclear fuel production and other energy costs significantly influence the demand for renewables, as well as the level of subsidy and government tax policy. In addition, the international and national programs, objectives, strategies, subsidies and regulatory measures as well as technological factors can have a significant impact.

    In my paper I point out the opportunities of renewable energy should be given to live. Nowadays the positive effects of their use is undisputed. In addition to the environmentally friendly produced energy, we should strive for energy conservation and energy efficiency as well. These expectations appear in practice, which can be directly perceived by citizens, in fact we should live accordingly. Furthermore, the environmentally relevant regulations of living conditions should appear as environmental demands.

  • Basic Research for the Development of Fertiliser Spreaders
    52-57
    Views:
    87

    The knowledge of the physical characteristics of fertiliser particles is essential for the constructors and operators of fertiliser distributors. Among physical characteristics, the most important are the frictional and aerodynamic properties for the description of particle movement. Adjustable angled slopes, shearing boxes and various rotating disks are used to identify frictional properties. We have developed a high precision shearing box with digital force measuring cells and a distance signaller (incremental transducer) that we use for slide tests efficiently. We measured the frictional characteristics of 6 different fertilisers: the inner coefficient of friction and the coefficient of friction on ten test surfaces most commonly used in machinery, and we specified the relationship between displacement, loading and the coefficient of friction. We can conclude that the material of the frictional surface significantly influences the force of friction.
    However, our experience tells us that the shearing box is not suitable for the measurement of the inner friction, since the examined particles slide on the metal surface of the shearing box in a growing extent in the course of displacement, so it does not measure the real inner friction. Therefore, in our experiment we have developed rotating shearing equipment with a constant shearing surface to identify the inner friction. We tested the equipment with fertilisers and we identified the inner frictional characteristics of 6 different fertilisers. With the developed rotating shearing apparatus we could measure the real inner friction of the particles.
    To identify the aerodynamic characteristics of granules, wind tunnels and free-fall tests are used. An elutriator have been developed for our investigation. We have used fertilisers for testing the measuring equipment and we have identified the aerodynamic characteristics of 6 different fertilisers.