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Abstract

Goal of in-service NDT carried out in engineering plants is to reduce operational risk via contribution to insurance of the components’ structural integrity. NDT in structural integrity assessment has two directions. One of the basic problems in reliability assessment of engineering components having crack like flaws is on how the crack sensitivity of the component can be defined in terms of characteristic numbers. If we would be able to define it than the hazard of different flaws could be compared by pure numbers. The definition and introduction of a Crack Propagation Sensitivity Index of a component has fundamental meaning because the experimental results of the NDT, the loading conditions and the crack propagation resistance are physically connected by applying fracture mechanics principles in the components reliability assessment.

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Abstract

Nowadays, the problem of energy poverty occurs more and more frequently and its solution is a serious and urgent task. Energy poverty is closely related to the poor energy performance of residential stocks. Energy poverty is simultaneously an energetic and social question, due to involving households having bad energetic parameters. Because of bad efficiency, the energy costs are highly related to earnings. It is not able to enhance the energy efficiency of buildings. Financial supports for endangered layers should contain measures to increase energy efficiency and decrease energy consumption. However, the concept of energy poverty is applied to social groups, like families or communities. In this paper, we extended the concept of energy poverty to SME (small- and medium-sized enterprises). The paper introduces the concept and the risk of energy poverty and the technology of measuring those risks.

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Changes in the chemical contents of the kernels of maize hybrids were analysed in three consecutive years (one dry, one arid and one wet) in samples originating from irrigation and fertilisation experiments. The results indicated that while irrigation and wet years had a protein-decreasing effect, the water supply did not influence the starch and oil contents. Under the influence of fertilization, the calcium and zinc contents of maize kernels decreased to varying degrees depending on the hybrid, while the sulphur contents changed parallel to the protein contents. Based on these data and on the use of more modern measuring equipment, tables giving recommendations for chemical contents should be revised.

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Deterministic seismic hazard computations were performed along four different profiles across the downtown of Budapest. Synthetic seismograms were computed by the so called “hybrid technique”. By applying the hybrid technique it is possible to take into account the focal source, the path and the site effect together. Four independent computations have been performed using the same seismic source but different profiles. The parameters of the seismic source were adopted from the parameters of the well-known 1956 Dunaharaszti earthquake. The focal mechanism and the homogeneous and heterogeneous parts of the profiles are known from geophysical and geological data of the investigated area.As the results of the computations PGA (peak ground acceleration) grid maps of the downtown of Budapest for the three different components came into existence. Furthermore spectral acceleration (response spectra, SA) and RSR charts of the synthetic seismograms for the four different profiles were created. The PGA grid maps show that the maximal PGA values are situated at the eastern (Pest) part of the downtown, and their values are 50–200 cm/s 2 .For the downtown of Budapest a special seismic risk map have been prepared. This special seismic risk map were created on the basis of the difference between the maximal amplitude frequencies of SA of synthetic seismograms and the building’s eigenfrequencies at every 0.1 km 2 of the downtown. In order to determine the building’s eigenfrequencies microseismic noise measurement were performed at 6 different buildings in the downtown. The special seismic risk map shows that the buildings situated at the hilly western section of the downtown have higher seismic risk than the ones at the flat eastern part.

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With flexible (variable) retirement every individual determines his optimal retirement age, depending on a common benefit-retirement age schedule and his life expectancy. The government maximises the average expected lifetime utility minus a scalar multiple of the variance of the lifetime pension balances to achieve harmony between the maximisation of welfare and the minimisation of redistribution. Since the government cannot identify types by life expectancy, it must take the individual incentive compatibility constraints into account. Second-best schedules strongly reduce the variances of benefits and of retirement ages of the so-called actuarially fair system, thus achieving higher social welfare and lower redistribution.

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The aim of the present study is a better understanding of the distribution and formation of salt efflorescences by mineralogical examination. Dominant sodium sulphate and sodium chloride surface efflorescences were selected for investigation. 24 samples were collected between 1999 and 2005 from 16 sites. The soil types were solonchak and meadow solonetz.Basic soil and groundwater analyses were performed according to the standard methods. Minerals were determined by X-ray diffractometry and SEM combined with microanalysis. The evaporation experiments were carried out in a Sanyo Versatile 350 HT environmental test chamber.It was concluded that common sulphate salts form rare and unique mineral associations on salt affected soils in Hungary.Comparing the groundwater compositions and the mineral associations of surface efflorescences or that of precipitated evaporites of groundwaters, the conclusion can be drawn that groundwater composition is reflected much better by the mineral association of experimentally precipitated evaporates of the groundwater than by the mineral associations of surface efflorescences. These differences suggest that the soil matrix may have an effect on the crystallization of minerals (e.g. gypsum, thenardite) in the efflorescences. The differences also suggest that in the surface efflorescences the precipitation process does not come to the end in all cases (minerals with high solubility are missing).Concerning the data on groundwater level depths in case of different (sodium carbonate versus sodium sulphate and sodium chloride) efflorescences, there is a tendency of declining groundwater table in the sequence of these soils. This difference can be explained by the difference (increase) in the solubility of various salt minerals.It was recognized that the change in the major component of surface efflorescenes in time (i.e. the sodium carbonate and sodium carbonate chloride versus sodium sulphate efflorescences before and after 1998) can be explained by the decline of the groundwater level and by the decreasing hydromorphic influence in the lowland area during the 19th and 20th century.Finally it can be stated that the presented research — which mainly focused on mineralogical aspects — has contributed to the earlier knowledge on surface salt efflorescences, which was based only on their chemical composition.

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Acta Alimentaria
Authors: P. Molnár, G. Várkonyi, and M. Tóth

Auditing in the food industry: M. Dillon and CH. Griffith (Eds), Woodhead Publishing, Limited, Cambridge, 2001, ISBN 1 85573 450 8, 222 pages EU food law: K. Goodburn (Ed.), Woodhead Publishing Limited, Cambridge, 2001, ISBN 1 85573 557 1, 244 pages  Food chemical safety: D. H. Watson (Ed.), Vol. 1: Contaminants, CRC - Woodhead Publishing Limited, Cambridge, England, 2001, ISBN 1 85573 462 1, 322 pages, Vol. 2: Additives ISBN: 1 85573 563 6, 308 pages

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The statistical analysis of salinity data from samples collected yearly from genetic soil horizons of 69 points of the Hungarian Soil Information and Monitoring System between 1992 and 2000 showed changes in time. There is a strong atmospheric control over the groundwater level and the resulting soil salinity. Weak statistical association was established between either the pattern of yearly soil salinity changes in the second (10-20 cm) and third (30-40 cm) genetic horizon and the groundwater observation stations or the soil types. In the area of Kecskemét there was a tendency of decreasing soil salinity patterns, while around Békéscsaba a tendency of increasing soil salinity patterns, as illustrated by the correspondence biplot. Regarding soil types, the solonetzic meadow soil showed a tendency of increasing salinity. It was concluded that the statistical analyses of the monitored data must be carefully planned in order to provide the optimal background data as independent data from all those available to accompany the monitored soil data as dependent variable.

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The Hungarian Detailed Soil Hydrophysical Database, called MARTHA ver2.0 has been developed to collect information on measured soil hydraulic and physical characteristics in Hungary. Recently this is the largest detailed national hydrophysical database, containing controlled information from a total of 15,005 soil horizons. Two commonly used pedotransfer functions were tested to evaluate the accuracy of the predictions on the MARTHA data set, representative for Hungarian soils. In general, the application of both examined pedotransfer functions (Rajkai, 1988; Wösten et al., 1999) was not very successful, because these PTFs are representative for other soil groups. The classification tree method was used to evaluate the effect of soil structure on the goodness of estimations. It was found that using the soil structure data the inaccuracies of soil water retention predictions are more explainable and the structure may serve as a grouping variable for the development of class PTFs.

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Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is one of the most important pests of greenhouse pepper in Hungary. It has a hidden lifestyle, a short generation interval and a high reproductive rate. Due to these characteristics it is difficult to obtain an effective, environment-friendly and harmless control of the pest. Previous studies have shown that under caged plant conditions, the common crab spider, Xysticus kochi (Thorell) (Araneae: Thomisidae) is effective against western flower thrips. In this study, we examined some of the technological questions of the use of spider larvae.We investigated the necessary amount and number of applications of spider larvae under caged plant conditions. The efficiency of spiders at the whole greenhouse level was also studied. While the ratio of damaged surface of peppers treated with X . kochi was significantly lower than that of non-treated plants, increasing the amount of spider larvae did not improve the effectiveness of thrips control. Although whole greenhouse experiences showed a similar, significant decrease in the rate of damaged surface in the case of peppers treated with spider larvae, when compared to untreated control; the efficiency of spiders remained below the level of economic acceptance.

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