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  • Author: Laszló Toth x
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Measurement of cognitive ability and thinking level of 10- and 13- year-old football players with football-specific tasks

Study aim: To assess whether in a special area, such as football, formal thinking may appear as early as at the age of 10 years.

Material and methods: In total 50 children divided into three groups took part in the study: 10-year-old football players from the Premier League Team - level 1 (Group 1; n = 22), 10-year-old football players from the Football League Team - level 3 (Group 2; n = 13) and 13-year-old football players from the Premier League Team - level 1 (Group 3; n = 15). With the help of specific motor tests, the kinetic memory, level of thinking and technical level were assessed.

Results: The 10-year-old children representing lower levels of football proficiency (Group 2) were significantly (p<0.05) inferior to their mates from the Premier League in both the level of thinking as well as in kinetic memory. No significant differences were found between members of Group 1 and Group 3 in any of the studied variables.

Conclusions: The results support the thesis that 10-year-old children are able to use formal thinking in a particular area, such as football. To be aware of this would be of great importance to those experts who deal with selection and talent identification.

Összefoglalás

A kisemlősök denzitás változásainak az egerészölyv reprodukciójára gyakorolt hatását (un. numerikus választ) vizsgáltam a Hortobágyon, 2000-2001-ben. A fészekellenőrzések során regisztráltam a lerakott tojások, valamint a kikelt és a kirepült fiókák számát. Az egyik legfontosabb zsákmánycsoport, a kisemlősök állomány változásait élvefogó csapdázással monitoroztam. Vizsgáltam az időjárásnak az áttelelő kisemlősök túlélésére gyakorolt hatását is. Az ölyvek átlagos fészekalja a két évben szignifikánsan különbözött: 2000-ben 2,3, míg 2001-ben 3,1 tojás volt. Ez a kisemlősök - 2000-ről 2001-re bekövetkezett - jelentős mértékű állománynövekedésével magyarázható. 2000-ben nagyon alacsony volt a kisemlősök egyedszáma (9 példány/ha), míg 2001- ben ennek nyolcszorosát regisztráltam (76 példány/ha). A kisemlősök egyedszámában tapasztalt óriási eltéréseket a vizsgált két év tél végi-tavasz eleji időjárási különbségei okozhatták. 2000 február-márciusában, a napi minimum hőmérsékleteket tekintetve, 4 rövid, enyhe periódus váltakozott 4 fagypont alattival, ugyanakkor az enyhe időszakokban jelentős mennyiségű (6-8 mm) eső is hullott. Ekkor az áttelelő kisemlősök járatai ismételten beáztak, az állatok megfáztak, kihűltek, szinte kipusztultak a területről, ezért létszámuk a költési időszakban is rendkívül alacsony volt. 2001-ben a tél vége sokkal enyhébb volt, 3 héttel korábban emelkedtek fagypont fölé a napi minimum hőmérsékletek, mint 2000-ben, nem alakultak ki váltakozó hideg-meleg időszakok sem. Ez kedvezően hatott az áttelelő kisemlősökre, létszámuk gyorsan emelkedett és nyár elejére mezei pocok gradáció alakult ki.

Abstract

Using Goursat’s lemma for groups, a simple representation and the invariant factor decompositions of the subgroups of the group Zm × Zn are deduced, where m and n are arbitrary positive integers. As consequences, explicit formulas for the total number of subgroups, the number of subgroups with a given invariant factor decomposition, and the number of subgroups of a given order are obtained.

Abstract

We survey arithmetic and asymptotic properties of the alternating sum-of-divisors function β defined by β(pa) = pa − pa−1 + pa−2 − · · · + (−1)a for every prime power pa (a ≥ 1), and extended by multiplicativity. Certain open problems are also stated.

Abstract

Due to conservation measures, the breeding population of the Raven significantly strengthened over the last decades in Hungary, also nesting on the lowlands. Nowadays, observing large flocks is not rare. Compared to other European countries, the urbanization of the species began relatively late in Hungary, in the ‘90s, first breeding in the urban areas of Baranya County. There were another five similar known cases after the millennium across the country. Because of the advanced adaptive capacity of species, this number is likely to grow in the future. In Hungary, the brood is typically complete in the second half of February and the young birds fledge in the first days of May. There are two known cases after the millennium when the Ravens bred in a significantly different time than usual. In these cases, the young birds fledged on 20 January and the second half of February. In both cases, the nests were found on overhead transmission line poles in lowland agricultural areas. It is uncertain what led to the unusual breeding time, but it is most likely that the breeding pair was accustomed, having successfully raised several brood before, and they could rely on the abundant food base near the nests during the breeding period.

Abstract

This paper deals with the pyrolysis of forest waste in the presence of an inert atmosphere. Experiments are carried out at different heating rates (5 °C, 10 °C and 15 °C) to determine derivative thermogravimetric behaviour of the material. Unlike the conventional scheme, the Monte Carlo technique is implemented to solve the distributed activation energy model (DAEM). DAEM is transformed into the inverse pyrolysis problem to determine the kinetic parameters of thermal degradation of forest waste. Activation energy, the preexponential factor and the distribution parameters are estimated by introducing the Monte Carlo Technique in the thermal conversion process.

Abstract

It is known that fusion welding can cause a decrease in the corrosion resistance of the heat affected zone of unstabilized stainless steels. The reason for this problem is that the welding heat (in the heat affected zone (HAZ)) can cause chromium-carbide (Cr23C6) precipitation with the simultaneous reduction of chromium content at the local grain boundaries. The chromium content dictates the corrosion resistance level. The relationship between surface roughness and corrosion behaviour is well known. We sought to find the difference between the corrosion resistance and surface roughness relationship in the case of cold rolled stainless steel and in the case of heat treated (welding heat effect simulated) stainless steel [1-3].

Abstract

The microstructure of the investigated X153CrMoV12 grade tool steel in delivered condition consisted of spheroidal matrix and primary carbides. The primary carbides were not dissolved under austenitisation time on either 1030°C or 1070°C. The microstructure and abrasion resistance of the steel changed due to quenching from different austenitisation temperatures. After conventional quenching from the higher austenitising temperature, there is more residual austenite in the steel than at quenching from the lower austenitisation temperature, which decreased the wear resistance. As a result of quenching from 1070°C followed by a multiple tempering process around 500 to 540°C, the retained austenite content is reduced and finely dispersed carbides are precipitated in the matrix, resulting in a higher matrix hardness and an increased wear resistance. After cryogenic treatment, the residual austenite content decreases compared to the conventional process, which leads to an increase in hardness and wear resistance.

Abstract

The most notable role in the energy usage of rearing-related buildings belongs to barn climate. For animals, one of the most important climate parameter is the temperature of the barn atmosphere. This can be kept in the proper interval by either heating or cooling. Apart from the operation of technological solutions, the need for airing barns must be taken into consideration. This means there are special technical requirements for airing. Also, they can cause significant energy losses. The temperature limit of heating is mainly influenced by the technological temperature related to keeping the animal in question, its acceptable differences, the heat loss of the barn, and the airing requirement. Energy sources applicable to heating can be traditional sources (coal, oil, gas), renewable sources (solar, biomass, wind, water, or geothermal energy), or transformed energy (electricity). As these have specific operation systems, they also mean further challenges in implementing efficient energy usage. The usage of heating energy can either be optimised by the rational usage of the heating system, or machinery explicitly made for reserving energy. Sparing heating energy via recuperative heating exchange may cut costs significantly, which we also proved in this research with actual calculations. However, we have to state that the efficient usage of heat exchangers requires that the internal and external temperatures differ greatly, which has a huge impact on heat recovery performance.

Abstract

In this work, the authors give an overview of the advancement of industrial robots and show the mechanization of welding processes, step by step. As manual welding is a physically exhausting professional work, engineers have sought to improve work conditions since the industrial revolution. Unfortunately, even today, many procedures can only be performed manually. In the welding process, the highest level of mechanization is represented by the use of robotics. The entrance of Robots in the history of welding is recent, though their spread and development are rapid.