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A new quasi-geoid model for Hungary was determined by combining gravity data, GPS/levelling and vertical deflections. Reduction of the measurements was performed by using Earth Gravitational Model 2008 (EGM2008) and Shuttle Radar Topographic Mission (SRTM) elevation data sets. Calculation method was Least Squares Collocation (LSC) with self-consistent planar logarithmic covariance model. In the computations the weights of GPS/levelling data were large, in this way normal heights obtained from levelling are consistent with GPS heights and with the quasi-geoid model. Astrogeodetic-gravimetric, pure astrogeodetic and pure gravimetric solutions have been calculated besides the combined solution to investigate the discrepancies among the different models. The combined quasi-geoid model fits to the GPS/levelling data with standard deviation of ±4.9 cm, nevertheless at some GPS/levelling sites large differences were indicated.

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Topographic masses have a strong impact on the medium and short wavelength components of the gravitational signal generated by the mass of the Earth, thus digital terrain models (DTM) are routinely involved in gravity field modelling. In this study the verification of the Shuttle Radar Topographic Mission (SRTM) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM) which is a joint product of METI (Ministry of Economy, Trade and Industry of Japan) and NASA has been done by comparing them to the points of the horizontal and vertical control networks of Hungary. SRTM data fit better to geodetic ground control points than ASTER GDEM, since some artefacts have been found in ASTER elevation set which impede further use of the latter without any pre-processing. Since SRTM is an “unclassified” surface model including all those points which reflected the scanning radar signal thus tree canopy height has been compared to the differences of SRTM and DTM elevations in a hilly test area in Hungary where a local and accurate DTM having 20 m × 20 m horizontal resolution was available. Considerable agreement was indicated between forest height and model differences. Model differences were evaluated to determine their effect synthetically on gravity related quantities. Their influence on geoid height is insignificant, but the change of the investigated second derivatives of the potential is considerable.

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Abstract

This study deals with the leadership attitudes of local authorities in the North Great Plain region. The study is part of a research project dealing with organisational culture. In order to examine the organisational culture, the GLOBE (Global Leadership and Organisational Behaviour Effectiveness) questionnaire was used, which was also applied in the research programme “Compete the World!” at the Corvinus University in Budapest. Koopman, Den Hartog, Konrad et al. (1999) examined the culture variables of 21 European countries, while Brodbeck et al. examined the values of leadership variables in European clusters. This study deals with the examination of the leadership variables of local authorities. No similar examination of local authorities has ever been presented in the Hungarian and international specialised literature.

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Abstract  

Soon after the discovery of the Mössbauer effect, studies were performed on spinels containing various transition metal ions (mostly Fe2+). This method proved very useful for investigating the local symmetry at transition metal ions. In spite of the numerous results, the correct interpretation of the complex quadrupole split spectra is still not given for numerous spinel structures. Since spectra of different shapes were measured for FeAl2O4 and FeCr2O4 by different authors, we performed new measurements on these spinels. The results on FeAl2O4 showed that the statistical distribution of another kind of ions in the positions A may influence the electric field gradient at the Fe2+ ions in the tetrahedral interstices. In FeCr2O4 and in the mixed Fe0.5Mg0.5Cr2O4, the electric field gradient exists at the Fe2+ ions at room temperature indicating that the degeneracy of the orbital doublet of the Fe2+ is removed.

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This paper introduces the alternating conditional expectation (ACE) algorithm of Breiman and Friedman (1985) in multiple regression problems in groundwater monitoring data analysis. This special inverse nonparametric approach can be applied easily for estimating the optimal transformations of different groundwater monitoring data from the Bükk Mountains to obtain maximum correlation between observed aquifer variables. The approach does not require a priori assumptions of a mathematical form, and the optimal transformations are derived solely based on the groundwater data set. The advantages and applicability of the proposed approach to solve different multiple regression problems in hydrogeology or in groundwater management are illustrated by means of case studies from a Hungarian karst aquifer. It is demonstrated that the ACE method has certain advantages in some fitting problems of groundwater science over the traditional multiple regression.In the past, different groundwater monitoring data (like groundwater level, groundwater temperature and conductance, etc.) had been used for groundwater management purposes in the Bükk Mountains. One of the difficulties in earlier approaches has been the need to make some kind of assumption of the expected mathematical forms among the investigated reservoir and petrophysical variables. By using nonparametric regression, the need to assume a specific form of model is avoided, and a clearer vision of the relationships between aquifer parameters can be revealed in the Bükk Mountains, where karst water is the main source of potable water supply. Complex monitoring data from the Bükk Mountains were analyzed using the ACE inverse method, and results were verified successfully against quantitative and qualitative field observations.

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Today, companies have to face new challanges because of the globalization, new technologies, globalization of markets and increasing competition. In this accelerated world, it is essential that the companies adapt to the market, which is only available through the necessary information. The importance of market research is undoubted. In our study we would like to prove that in case of a beginner company — in this case a confectionery — it is important to perform a market research like for a company in any other segment. To perform it, the qualitative market research methods were used. Our questionnaire examines several aspects in order to provide an indication of the company’s founding.

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Fractured fluid reservoirs are of key importance for recovering water and hydrocarbon supplies and geothermal energy, or in predicting the subsurface flow of pollutants. There are several fractured metamorphic-basement HC reservoirs in the Pannonian Basin; one of the largest among them is the Szeghalom Dome in SE Hungary. Previous production and fluid inclusion data infer that in this case several unconnected fluid regimes must coexist in the basement, making modeling of the fracture network essential. Because the representative volume of a fractured rock mass is usually too large to measure hydraulic properties directly, stochastic calculations should be carried out, which are consistent with observed deformation history and stochastic patterns. Input statistical data (orientation, length, distribution, fractal dimension for fracture seeds) were determined for amphibolite and gneiss samples representing the Szeghalom Dome. Data were measured simultaneously using binocular microscope and computerized X-ray tomography. Comparison of the two data sets suggests that they are comparable and both can be used for modeling. A new computer program, called REPSIM has been developed recently, which follows a fractal geometry-based discrete fracture network (DFN) algorithm to simulate the fracture network. The evaluation of simulated networks suggests that amphibolite and gneiss-dominated parts of the basement behave differently; large amphibolite bodies have a connected fracture network, while gneiss domains usually are well below the percolation threshold.

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In this study a simple and effective method was developed for the isolation of Saccharomyces strains from grapes. Aseptically collected grape samples were processed by enrichment in a nutritive basal medium supplemented with 10% (v/v) methanol followed by isolation of yeast strains. Sixteen of the 18 grape samples yielded Saccharomyces strain(s). More than 70% of the isolates belonged to the genus Saccharomyces. Based on phenotype and electrophoretic karyotyping, all strains of Saccharomyces were identified as S. cerevisiae. For several grape samples, varying physiological characters, the number of spores per asci, and the observed chromosome length polymorphisms provided evidence for diversity of S. cerevisiae strains obtained by this enrichment in methanol-containing broth. Results indicated that enrichment in methanol-containing broth is an effective alternative method to facilitate isolation of Saccharomyces strains from grapes. The enrichment method described in this work provides a simple and effective tool for isolation of Saccharomyces strains from grapes. The method may be applied in studying wine fermentation ecology, as well as for the isolation of potential starter strains from grapes.

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The meat of 21 Hungarian Simmental and 17 Holstein-Friesian cattles was analysed for fatty acid and amino acid content, and also for the biological value of the meat protein. It can be established that the proportion of the saturated and the mono- and polyunsaturated fatty acids compared to each other is not significantly influenced by the breed and the live weight at the various types and weight categories. The increase in the live weight goes together with the increase in the ratio of the monounsaturated fatty acids in the meat in case of both breeds. The amino acid content of the meat was not significantly influenced by the breed, even the live weight didn't demonstrate any effects. The essential amino acid content and the biological value of the meet of the Hungarian Simmental are practically the same as those of the Holstein-Friesian.

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The healing process of telescopic anastomoses was found in an animal experiment with 12 mongrel dogs. After the division of vessels an ileal segment of different length was invaginated into the lumen of the colon using single-layer interrupted sutures. The following four groups were used: Group A (n = 3): end-to-side ileocolostomy, single-layer interrupted suture (invagination length: 0 mm), survival time: 21 days. Group B (n = 3): invagination length: 20 mm, survival time: 7 days. Group C (n = 3): invagination length: 10 mm, survival time: 21 days. Group D (n = 3): invagination length: 20 mm, survival time: 21 days. At the end of the above survival times the anastomosis area was removed. The bursting pressure was measured and morphological as well as histological examinations were performed. In each case the 0-day look-alikes of anastomoses were performed using the remnant bowels, and bursting pressure measurements were done on these models as well. Anastomosis leakage did not occur. The serosal layer of the intracolonic part of the ileum disappeared during the healing process. The free surface of the intracolonic ileal segment became covered by the sliding mucosa of the colon and the prolapsing mucosa of the ileum. The following could be concluded after the experiments: The inner pressure tolerance of a telescopic ileocolostomy promptly after preparation is better than in case of another single-layer anastomosis. This fact results in increased safety against leakage on the first postoperative days. The inner pressure tolerance of the telescopic ileocolostomy increases during the healing process and it does not depend on the length of the invaginated part (0 day-20 mm: 56 mmHg ± 6, Group A: 252 ± 39, Group B: 154 ± 19, Group C: 249 ± 20, Group D: 298 ± 2). There is no difference in pressure tolerance between the telescopic and the end-to-side single-layer interrupted anastomoses after the healing process. The invaginated section within the lumen of the large intestine does not suffer ischaemic or any other kind of damage. This inexpensive and simple anastomosis technique could be useful in the veterinary surgical practice as well.

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