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Acta Oeconomica
Authors: Balázs Borsi and György Kovács
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Acta Oeconomica
Authors: Balázs Muraközy and Tamás Kovács
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Understanding and simulating the interaction of groundwater and surface water is essential to hydrologists. Water supply and water quality aspects are a few examples of common water-resource issues where understanding the interconnections of groundwater and surface water is fundamental to develop an effective water-resource management and policy. In our study a detailed investigation of a riverbank aquifer was performed to be able to simulate and predict the behavior of the flow system. The continuous hydraulic head measurements in the area of interest showed strong influence on the hydraulic head field caused by intensively changing river head at a distance from the river up to 3,500 m. Based on the results steady state and transient flow calculations were compared, and a great effort has been made to ensure that the model more precisely describe the time and space variable flow field. Beside fulfilling the standard calibration requirements, a multi-step calibration process was performed.

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Abstract

Fissuring of rocks is frequently of greater importance in practical rock engineering operations than the strength of the intact rock. In practice boreholes are usually analyzed by the RQD method. The limitation of this method has been discussed by several authors: for example, for RQD = 0 % [that is, where the joint intercept (distance between joints in the cores) is 10 cm or less], or RQD = 100%, the RQD provides no information on the core pieces themselves. It does not matter whether the discarded pieces are soil or fresh rock pieces up to 10 cm in length. In early 2003, more than 3,000 meter-long boreholes were analyzed in parallel with two different methods: traditional RQD, and Hansági's C (or Kiruna) Method. According to the results, in the case of a very good or very poor core, the C method shows the jointing patterns better than the widely-used RQD method. The goal of this paper is to present the C method and its advandages/disadvandages. Linear regression was found for the values between 10% < RQD < 90%, but the C value is much more sensitive than the RQD. The classification of the boreholes according to C method is also presented.

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The geologic, geotechnical and rock mechanical background of the area, which includes an underground cavern system, is very complex. Initially, to describe the rock mass properties, the RMR and Q systems were used, while the rock support system was based solely on the Q system. Later, during construction of the repository chambers, the GSI system was also introduced in addition to the above-mentioned rock classification methods. The correlation and usage of these three different rock mass classification systems were investigated.Special methods were used to obtain more accurate tunnel mapping and documentation, which is based on photogrammetry and photo analyzer software.According to the results, the correlation between the RMR and Q values is independent of the rock type; basically, the same equation can be used for all (differences between experimental error). The GSI intervals also closely follows the same trend as the results of the other two methods.

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With the intent of making data acquisition for fractal geometry-based discrete fracture network (DFN) modeling time-efficient and automatized, a new method was established. For the automation of data retrieval from the images of the studied surfaces, a series of image-processing operations and MATLAB algorithms have been developed. The method allows the retrieval of more than 1,000 fracture-length data/cm2 of one sample in several minutes. This methodology tends to be a useful tool in studies of fracture network geometries. DFN models of a supposed excavated and/or environmental damage zone, designed with the use of data supplied by the above method, are presented in this work as an example.

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Bolygónk lakosságának 2–3%-át érinti a hepatitis C-vírus-fertőzés, amely a fertőzöttek több mint felénél krónikus májgyulladást okoz, és a májzsugorodás, a májelégtelenség, a májsejtrák, az ezek miatt szükségessé váló májátültetés, valamint a májeredetű halálozás egyik leggyakoribb oka. A XXI. század első évtizedében arany standarddá vált pegilált interferon-alfa és ribavirin kettős kezeléssel a hazánkban domináló G1 genotípussal fertőzött, korábban még nem kezelt betegek ~40%-a ér el tartós vírusmentességet, a korábban sikertelenül kezelt betegek ismételt kezelésekor pedig csak minden ötödik. A közelmúltban törzskönyvezett két új, hepatitis C-vírus elleni proteázgátló, direkt antivirális hatású készítmény (boceprevir és telaprevir) hozzáadásával a korábban még nem kezelt betegek csaknem háromnegyede, a korábban sikertelenül kezelt betegeknek pedig több mint fele számíthat gyógyulásra. A terápia sikerét jelentősen korlátozza, hogy a gyakori – és esetenként súlyos – mellékhatások miatt a gyógyszereket a betegek egyharmada az optimálisnál alacsonyabb dózisban és/vagy rövidebb ideig kaphatja. További kihívást jelent, hogy a kettős kezelés során alkalmazott készítmények mellékhatásait az új készítmények fokozhatják (különösen anaemia), másrészt új mellékhatások is jelentkezhetnek (például boceprevir esetén ízérzészavar, telaprevir esetén bőrkiütések). Az összefoglaló célja a terápiához kapcsolódó mellékhatások és ezek kezelésének áttekintése a készítmények alkalmazási előírásai, az ezek alapját képező közlemények és a készítményeket használó szakemberek tapasztalatai alapján – abban a reményben, hogy ez segítséget nyújthat a kezelést végző kollégáknak a standard és az új készítmények biztonságos és hatékony alkalmazásához. Orv. Hetil., 2011, 152, 1997–2009.

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Az Alzheimer-kór heterogenitása

Heterogeneity of Alzheimer’s disease

Orvosi Hetilap
Authors: Nóra Balázs and Tibor Kovács

Összefoglaló. A neurodegeneratív betegségek között az Alzheimer-kór a leggyakoribb kórforma. Morbiditása és mortalitása világszerte egyre gyorsabb ütemben növekszik, ezáltal szociális és gazdasági hatása is folyamatosan fokozódó terhet jelent a társadalomra. Az elmúlt néhány évtizedben jelentős előrelépés történt az Alzheimer-kór megismerésében, számos biomarker támogatja a diagnózis felállítását, tüneti terápiát szolgáló gyógyszerek kerültek bevezetésre. Az Alzheimer-kór klinikai megjelenése, lefolyása, viselkedése rendkívül változatos képet mutat, felismerése a rendelkezésre álló eszközök ellenére is kihívást jelenthet a nagy tapasztalattal bíró klinikusok számára is. Munkánk céljául tűztük ki, hogy összefoglaljuk az Alzheimer-kór genetikai, patológiai és klinikai jellemzőit, segítve ezzel a betegség jobb meg- és felismerését. Bemutatjuk a jelenleg érvényben lévő patológiai és klinikai irányelvek kritériumrendszereit, az újabb klasszifikációs szemléleteket. Részletesen ismertetjük az Alzheimer-kór heterogenitását genotípus és fenotípus szintjén egyaránt. Elemezzük a típusos és atípusos megjelenési formák jellemzőit, a társuló kórállapotoknak a megjelenésre és a progresszióra gyakorolt hatását. Orv Hetil. 2021; 162(25): 970–977.

Summary. Alzheimer’s disease is the most prevalent neurodegenerative disorder. Morbidity and mortality of Alzheimer’s disease are increasing worldwide causing important social and economic burden on the society. Over the past few decades, significant progress has been made in the understanding of the pathogenesis of Alzheimer’s disease, several biomarkers support the diagnosis and drugs for symptomatic therapy had been introduced. The clinical manifestations and the course of Alzheimer’s disease have a variable picture, so – despite the diagnostic opportunities – its diagnosis could be a challenge for highly experienced clinicians as well. The aim of our work was to summarize the genetic, pathological and clinical characteristics of Alzheimer’s disease, thus helping to better understand and recognize the disease. We present the criteria systems of the currently valid pathological and clinical guidelines with the most recent classification approaches. The heterogeneity of Alzheimer’s disease at both genotype and phenotype levels is described in detail. The characteristics of typical and atypical manifestations and the effect of co-pathologies on the appearance and progression of Alzheimer’s disease are also discussed. Orv Hetil. 2021; 162(25): 970–977.

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Particle size distribution (PSD) is one of the most important fundamental physical properties of soils, as it determines their physical, chemical, mechanical, geotechnical, moreover environmental behaviour. Although the measurement of PSD with different techniques is commonly performed in soil laboratories, their automation and continuous PSD curve generation have not been solved yet.  However, there are some physical principles, various sensors and different data storing methods for measuring the density-time function. In the present paper a possible solution is introduced for the measurement of the soil particle density database as a function of settling time. The equipment used for this purpose is an areometer that is widely used e.g. for determining the sugar content of must, or the alcohol content of distilled spirits, etc. The device is equipped with patent pending capacitive sensors on the neck of the areometer. It measures the changes in the water levels nearby the neck of the areometer in 1 μm units with <10 μm accuracy. The typical water level changes are 3-5 cm, which makes possible a very accurate determination of particle density changes due to settling in particle size analysis. The measured signals are stored in the equipment's memory and can be downloaded to the controller computer via a modified USB port. Data evaluation can be carried out online or later. The large number of measured data points led to the introduction of a new evaluation method, the Method of FInite Tangents or shortly the “FIT Method”. The dispersed soil particle system is considered as the aggregation of many mono-disperse systems. From this it follows that the measured density-time function can be divided into grain size fractions with tangent lines drawn to finite, but optional points. These tangent lines are suitable for calculating the settling speed of a given fraction, as the changing speed of density is equal to the multiplication of settling speed and mass of the given grain size fraction. The settling speed of all fractions is calculable by using the Stokes law, so the mass of all of the floating fraction can be calculated. Because the soil suspension is a poly-disperse system, the measured density decrease can be considered as an integration of finite mono-disperse systems. From this, it follows that it can be interpreted as the sum of linear density vs. time functions. If the mass of each grain size fraction is known, the particle size distribution is calculable. The method is relatively easily programmed and the intervals of grain size fractions are freely adjustable, so with this program almost all types of particle size distribution are calculable, not only those being uniform. Using the appropriate controller and evaluation program, soil particle size distribution can be calculated immediately after downloading the measured data. This technique does not need more sample preparation than past methods. The automated reading lessens the manpower required for performing the measurement - which also reduces human error sources - and provides very detailed PSD data that has advantages, among others, like revealing multi-modality in the particle-size distribution.

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