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Open access

Zoltán Németh

Abstract

The Common Blackbird is a partial migrant throughout much of its range in Europe. That is, part of its breeding population migrates while the rest stays at the breeding ground for winter. Given the rapidly changing global climate, it is important to understand how migratory birds, including partial migrants, respond to shifting climatic conditions. In this study, I analyzed 85 years of ring recovery data of the Hungarian population of the Blackbird, ringed during the breeding season and recovered during migration or winter, with two objectives in mind: (1) to assess whether the Hungarian Blackbird population is also partially migratory, and (2) to test the prediction that Blackbirds have exhibited decreasing migration distances over the past decades as expected based on warming winter temperatures. Hungarian Blackbirds expressed both migratory and resident strategies, thus can be considered as partial migrants. Furthermore, Blackbirds had been recovered increasingly closer (-5.9 km/year) to their breeding grounds in the past decades. Age and sex had no effects on recovery distance. Provided that this trend continues, the adaptive benefits of migratory behavior may eventually be reduced to a level that selection will not maintain it in the population and the Hungarian population becomes entirely sedentary. Surprisingly, 88% of migrant recoveries were the result of shooting or hunting activities in Mediterranean countries, primarily in Italy, highlighting both the need to understand the effects of hunting pressure on migratory behavior at the population level in songbirds and the urgency to ban the killing of migratory birds in European countries.

Open access

Zoltan Nemeth, Krisztina Dajnoki, David Suto and Veronika Fenyves

Abstract

Nowadays, due to the social and economic changes, the human is already the main resource which determines the successfulness of corporations. The expertise in managing the human resources is a key factor of competitiveness therefore it has become a strategic question. Primary aim of the treatise is to outline the most important principles, targets and peculiarities of performance management system, which is a central element of human resource management, as well as its interconnectedness with the individual performance evaluation and human resource development through the mirror of one of today’s biggest Hungarian economic corporations. We aimed to explore, by means of document analysis as well as methods of case study and interview, how the targets of performance management are used for increasing the economic productivity, preserving the competitiveness, retaining and enhancing the satisfaction of workers. It can be stated that the PM system was continuously improved in case of the organization examined because the corporate goals and the expected performances were adjusted to the changing market demands over time but, at the same time the goal of differentiation has remained unchanged. Each worker evaluates his/her performance individually, the base of which is the extent of contribution to the corporate results. Based on the results, it can overall be stated that such a well-functioning performance management system is applied in the operating unit of the corporation examined which is strongly supported by the organizational culture and which contributes to the joint fulfilment of personal as well as organizational goals.

Open access

Boldizsár Németh and Zoltán Csörnyei

Abstract

Compilers generate from the procedure or function call instruction a code that builds up an ”activation record” into the stack memory in run time. At execution of this code the formal parameters, local variables, data of visibility and the scope are pushed into the activation record, and in this record there are fields for the return address and the return value as well. In case of intensive recursive calls this is the reason of the frequent occurrences of the stack-overflow error messages. The classical technique for fixing such stack-overflows is to write programs in stackless programming style using tail recursive calls; the method is usually realised by Continuation Passing Style. This paper describes this style and gives an introduction to the new, special purpose stackless programming language Miller, which provides methods to avoid stack-overflow errors.

Open access

Cs. Németh, L. A. Castillo, F. Horváth, I. Zeke, L. Friedrich, Cs. Balla, Z. Németh and P. Póti

Abstract

There are numerous new technologies whose implementation in food industry is hampered by the fact that people hesitate to invest in expensive systems which they cannot be sure will work or at least are questionable in terms of a given product. Until recently, preservation by HHP, high hydrostatic pressure, was such a technology, and still is today in some branches of the food industry. Investigations were conducted to answer the question of whether the literature, the laboratory, and the industrial (or at least pilot plant) measurements and results agree with one another. We compared the literature data with two HHP systems which were significantly different in terms of treatment capacity, but their efficiency in killing microbes was studied under the same treatment parameters. Our results show that in nearly all cases only minimal differences exist between the data in the literature and the measurements taken on the two appliances.

Open access

József Gyurácz, Péter Bánhidi, József Góczán, Péter Illés, Sándor Kalmár, Péter Koszorús, Zoltán Lukács, Csaba Németh and László Varga

Abstract

The fieldwork, i.e. catching and ringing birds using mist-nets, was conducted at Tömörd Bird Ringing Station in western Hungary during the post-breeding migration seasons in 1998-2016. Altogether, 106,480 individuals of 133 species were ringed at the station. The aim of this paper was to publish basic information on passerine migration at this site. Migration phenology was described through annual and daily capture frequencies. Furthermore, we provide the median date of the passage, the date of the earliest or latest capture, the peak migration season within the study period, and the countries where the birds monitored at the site were ringed or recovered abroad. To compare the catching dynamics for the fifty species with total captures greater than 200, a reference period was defined: from 5 Aug. to 5 Nov. 2001-2016. Some non-passerines that are more easily caught with mist-nets or that are caught occasionally were listed as well. The two superdominant species, the European Robin and the Eurasian Blackcap, with 14,377 and 13,926 total captures, made up 27% of all ringed individuals. Among the fifty species analysed, there were ten species with a decreasing trend, five species with an increasing trend and thirty-five species with a stable (or uncertain) trend in their numbers from 2001 to 2016. The temporal pattern of migration of long-distance migrants was different from that of the medium- and short-distance migratory species.

Open access

Zsolt Benkó, Ferenc Molnár, Marc Lespinasse, Kjell Billström, Zoltán Pécskay and Tibor Németh

Abstract

A combined fluid inclusion, fluid inclusion plane, lead isotope and K/Ar radiometric age dating work has been carried out on two lead-zinc mineralizations situated along the Periadriatic-Balaton Lineament in the central part of the Pannonian Basin, in order to reveal their age and genetics as well as temporal-spatial relationships to other lead-zincfluorite mineralization in the Alp-Carpathian region. According to fluid inclusion studies, the formation of the quartzfluorite- galena-sphalerite veins in the Velence Mts is the result of mixing of low (0-12 NaCl equiv. wt. %) and high salinity (10-26 CaCl2 equiv. wt. %) brines. Well-crystallized (R3-type) illite associated with the mineralized hydrothermal veins indicates that the maximum temperature of the hydrothermal fluids could have been around 250 °C. K/Ar radiometric ages of illite, separated from the hydrothermal veins provided ages of 209-232 Ma, supporting the Mid- to Late-Triassic age of the hydrothermal fluid flow. Fluid inclusion plane studies have revealed that hydrothermal circulation was regional in the granite, but more intensive around the mineralized zones. Lead isotope signatures of hydrothermal veins in the Velence Mts (206Pb/204Pb = 18.278-18.363, 207Pb/204Pb = 15.622-15.690 and 208Pb/204Pb = 38.439-38.587) and in Szabadbattyán (206Pb/204Pb = 18.286-18.348, 207Pb/204Pb = 15.667-15.736 and 208Pb/204Pb = 38.552-38.781) form a tight cluster indicating similar, upper crustal source of the lead in the two mineralizations. The nature of mineralizing fluids, age of the fluid flow, as well as lead isotopic signatures of ore minerals point towards a genetic link between epigenetic carbonate-hosted stratiform-stratabound Alpine-type lead-zinc-fluorite deposits in the Southern and Eastern Alps and the studied deposits in the Velence Mts and at Szabadbattyán. In spite of the differences in host rocks and the depth of the ore precipitation, it is suggested that the studied deposits along the Periadriatic-Balaton Lineament in the Pannonian Basin and in the Alps belong to the same regional scale fluid flow system, which developed during the advanced stage of the opening of the Neo-Tethys Ocean. The common origin and ore formation process is more evident considering results of large-scale palinspastic reconstructions. These suggest, that the studied deposits in the central part of the Pannonian Basin were located in a zone between the Eastern and Southern Alps until the Early Paleogene and were emplaced to their current location due to northeastward escape of large crustal blocks from the Alpine collision zone

Open access

Viliam Nagy, Gábor Milics, Norbert Smuk, Attila József Kovács, István Balla, Márton Jolánkai, József Deákvári, Kornél D. Szalay, László Fenyvesi, Vlasta Štekauerová, Zoltán Wilhelm, Kálmán Rajkai, Tamás Németh and Miklós Neményi

Abstract

A soil moisture content map is important for providing information about the distribution of moisture in a given area. Moisture content directly influences agricultural yield thus it is crucial to have accurate and reliable information about moisture distribution and content in the field. Since soil is a porous medium modified generalized Archie’s equation provides the basic formula to calculate moisture content data based on measured ECa. In this study we aimed to find a more accurate and cost effective method for measuring moisture content than manual field sampling. Locations of 25 sampling points were chosen from our research field as a reference. We assumed that soil moisture content could be calculated by measuring apparent electrical conductivity (ECa) using the Veris-3100 on-the-go soil mapping tool. Statistical analysis was carried out on the 10.791 ECa raw data in order to filter the outliers. The applied statistical method was ±1.5 interquartile (IRQ) distance approach. The visualization of soil moisture distribution within the experimental field was carried out by means of ArcGIS/ArcMAP using the inverse distance weighting interpolation method. In the investigated 25 sampling points, coefficient of determination between calculated volumetric moisture content data and measured ECa was R2 = 0.87. According to our results, volumetric moisture content can be mapped by applying ECa measurements in these particular soil types.