Authors:T. Mankovits, I. Kocsis, T. Portik, T. Szabó and I. Páczelt
This paper presents a novel solution for shape optimization of compressed rubber parts. The procedure is based on the finite element method (FEM). A special purpose FEM code written in FORTRAN has been developed for the analysis of nearly incompressible axi-symmetric rubber parts. Numerical stability of the code and sensitivity analysis of the FEM input parameters are investigated. The aim of the parameter optimization is to reduce the time consuming FEM computations for the optimization process. The objective of the optimization is to find the optimal shape of the investigated rubber parts with a specified load-displacement curve. A regression model is used to determine the connection between the input and output data calculated by the FEM.
Authors:R. Szabó, T. Szabó, B. Urbányi and L. Horváth
Secondary sexual characteristics such as softening and rounding of the abdomen as well as reddening and protrusion of the anal papilla and vent can be of help to breeders in selecting common carp (Cyprinus carpio) females prepared for propagation. To assess the reliability of this method, long-term data obtained on induced spawning of common carp at a large-scale fish hatchery were evaluated. The average spawning ratio of 2,620 females receiving hormonal injections was 79.8%. The average pseudogonadosomatic index (PGSI) calculated from data on the egg production of 2,086 females was 16.3 ± 5.87% (mean ± SD) for the same period. There was a correlation between fish weight and the time of induction determined by the breeder on the basis of external morphological characteristics. The similarity of the responses of females, including both spawning ratio and PGSI, among the different weight categories proved the reliability of this method for identification.
Authors:I. Fazekas, Gy. Szabó, Sz. Szabó, M. Paládi, G. Szabó, T. Buday, Z. Túri and A. Kerényi
The aim of our report is to refer on the actual state of small biogas power plants in Hungary summarising the increase in their number and capacity and their effects on climatic change. The above is based on the CO2 emission of the energetic utilization of biogas and the calculation of its ecological footprint that were compared to the environmental effects of natural gas energetic utilization. The aim of this paper does not include the complete life cycle analysis therefore the environmental benefits of the energetic utilization of biogas produced from various raw material are presented via only the direct CO2 emission of the production process.
Authors:T. Buday, Gy. Szabó, I. Fazekas, M. Paládi, Sz. Szabó, G. Szabó and A. Kerényi
Heating with the use of ambient energy by heat pumps is a very effective way to reduce CO2 emission. However, efficiency, economic and environmental advantages depend on the type of the heat pump and the temperature of the source, the latter usually changes during the heating season. The aim of the paper is to give the annual pattern of the COP and emission as a function of the typical source temperature pattern, moreover yearly summarized energetic and emission values are also added in the case of air source, water source and ground source heat pump systems, compared to some conventional heating mode.
Authors:T Szabó, L Ambrus, N Zákány, Gy Balla and T Bíró
The glomerular filtration barrier is a highly specialized tri-layer structure with unique functional properties. Podocyte dysfunction and cytoskeletal disorganization leads to disruption of the slit diaphragma, and proteinuria. Inflammatory diseases involving the kidney as well as inherited podocytopathies or diabetic nephropathy cause injury of the podocyte network. Focal segmental glomerulosclerosis (FSGS) is a pathologic entity that is a common cause of nephrotic syndrome with severe proteinuria in both adults and children. Several causative genes have been identified in the pathogenesis of FSGS. Mutations of the transient receptor potential canonical-6 (TRPC6), a non-selective cation channel that is directly activated by diacylglycerol (DAG), cause a particularly aggressive form of FSGS. Angiotensin II, acting through its AT1 receptor, plays a critical role in generation of proteinuria and progression of kidney injury in a number of kidney diseases, including FSGS. Mounting evidence suggest the central role of TRPC6 and perhaps other TRPC channels in the pathogenesis of FSGS as well as of acquired forms of proteinuria such as diabetic nephropathy or hypertension. Identification of signaling pathways downstream of TRPC6 may provide novel targets for the treatment of proteinuria and prevent progression of podocyte injury.
Authors:J. Somlai, N. Kávási, T. Szabó, A. Várhegyi and T. Kovács
It is suggested to spend some time in a cave for curing respiratory diseases. Some ascribe the healing effect partly to radon.
In Hungary in the Hospital Cave of Tapolca the mean radon concentration shows 17 times difference in the winter and in the
summer period. The change of the forced exhaled volume in 1 s (FEV1) values was examined measured by 1824 patients in this
cave. By 70% of the patients the FEV1 value improved, by 30% it became worse but these were independent from the radon concentration
of the cave. Therefore, radon concentration has no positive effect during the treatments performed in Tapolca.
Authors:H. Déri, L. Gy. Szabó, T. Bubán, Zs. Orosz-Kovács, T. Szabó and P. Bukovics
The sugar composition of the floral nectar was studied in 22 mainly Hungarian local quince cultivars in 2004. The material for investigation was taken from the quince genebank of the Research and Extension Centre for Fruitgrowing, Újfehértó, Hungary. The three main sugar components of the nectar were glucose, fructose and sucrose. Sucrose was present in the greatest amount in the nectar of all investigated quince cultivars. Glucose which is the least sweet among the three main nectar sugars for bees was present in the least amount. The nectar of most cultivars contained more fructose than glucose. The amount of the total nectar sugars was the lowest in cv. 'Pear-shaped Noszvaji' and the highest in cv. 'Kúti'. According to the Baker-quotient (S/F+G), the majority of the quince cultivars belonged to the sucrose dominant category. However, the cultivars 'Mezőkövesdi', 'Apple-shaped Dunabogdány' and 'Váli' had sucrose-rich nectar. The concentration of floral secretory product in all cultivars reached the threshold of bee visitation. The nectar refraction was lower at the end of bloom than in full bloom while flowers contained more nectar at the previous stage. The above results are important from the viewpoint of pollination biology, apiculture and defence against fire blight.
Authors:G. Szabó, P. Enyedi, Gy. Szabó, I. Fazekas, T. Buday, A. Kerényi, M. Paládi, N. Mecser and Sz. Szabó
According to the challenge of the reduction of greenhouse gases, the structure of energy production should be revised and the increase of the ratio of alternative energy sources can be a possible solution. Redistribution of the energy production to the private houses is an alternative of large power stations at least in a partial manner. Especially, the utilization of solar energy represents a real possibility to exploit the natural resources in a sustainable way. In this study we attempted to survey the roofs of the buildings with an automatic method as the potential surfaces of placing solar panels. A LiDAR survey was carried out with 12 points/m2 density as the most up-to-date method of surveys and automatic data collection techniques. Our primary goal was to extract the buildings with special regard to the roofs in a 1 km2 study area, in Debrecen. The 3D point cloud generated by the LiDAR was processed with MicroStation TerraScan software, using semi-automatic algorithms. Slopes, aspects and annual solar radiation income of roof planes were determined in ArcGIS10 environment from the digital surface model. Results showed that, generally, the outcome can be regarded as a roof cadaster of the buildings with correct geometry. Calculated solar radiation values revealed those roof planes where the investment for photovoltaic solar panels can be feasible.
Fluidized bed dryers are widely used in several fields of industry. Sufficiently accurate thermal models provide an opportunity to increase the effectiveness of dryers. The required size of a fluidized bed dryer can be defined with the application of mathematical model. This work is aimed at developing mathematical model to investigate the influence of operating parameters in a fluidized bed dryer using volumetric heat transfer coefficient. After the defining the input parameters of the differential equations, the required entry length of the dryer which effective heat and mass transfer between gas and particles takes place can be estimated. The correct estimation of the entry length is useful in optimal design of a fluidized bed dryer. Using the model the impact of the drying parameters can be determined to the required length.
Authors:Beáta Szabó, Á. Lakatos, T. Kőszegi and L. Botz
We aimed to understand the effects of water stress on the alkaloid production in various developmental stages of poppy plants and the effect of stress on the alkaloids content in the capsules. Three stages of the life cycle of
L. were selected in our studies: Rosette, Flowering and Lancing developmental stages. Four types of water conditions were examined: Control, Withdrawal of Water, 50% Water Supply and Inundation.The morphological monitoring, results of Relative Water Content and proline content were used as indicators of stress. The result of the measurements in poppy leaves show that the secondary metabolites dramatically respond to these stress conditions. The constant water supply was beneficial for the accumulation of alkaloids in the capsules.