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Studia Scientiarum Mathematicarum Hungarica
Authors: Nicolas T. Courtois, Theodosis Mourouzis, Anna Grocholewska-Czuryło, and Jean-Jacques Quisquater

). [4] Courtois , Nicolas , The Best Differential Characteristics and Subtleties of the Biham-Shamir Attacks on DES , on eprint.iacr.org/2005/202. [5

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References [1] Nyberg, K. and Knudsen, L. R. , Provable security against a differential attack , in: Advances in Cryptology

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Hogyan befolyásolja a villamosenergia-hálózatról rendelkezésre álló információ a fizikai támadások által okozott sérülékenységről alkotott képet?

A hazai energiaszolgáltatás túlélőképessége

How grid information affects the perception of vulnerability of the power grid under physical attacks.

Robustness of the Hungarian power grid
Scientia et Securitas
Author: Bálint Hartmann

., Zhu, J., Li, S., & Luo, T. (2020) Detection of False Data Injection Attack in Automatic Generation Control System with Wind Energy based on Fuzzy Support Vector Machine. Proc. IECON 2020 The 46th Annual

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. Aggregate expansivity due to sulfide oxidation, II, Physico-chemical modeling of sulfate attack , Cement and Concrete Research, Vol. 27 , No. 11 , 1997 , pp. 1627 – 1632 . [9

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the latter with dicalcium phosphate dihydrate (CaHPO 4 ·2H 2 O). This study deals with the calorimetric analysis of the attack of “B” type carbonate fluorapatites with a phosphoric acid solution having a composition close to that used in

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. és mtsa: Temporal trends and factors associated with extent of delay to hospital arrival in patients with acute myocardial infarction: the Worcester Heart Attack Study. Am. Heart J., 1994, 128 , 255

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Abstract  

This report deals with practical and experimental studies of the effects of frost attack on hardening cement stone and concrete. The basic component of concrete, cement stone, is a typical capillary-porous material formed from solid, liquid and gaseous phases. The level of knowledge on the effects of frost attack on cement stone and concrete hardening is insufficient, due to the complexity of the mechanisms of the accompanying effects. The values of internal pressures are determined among others by ice formation parameters, by the characteristics of the porous structure and the solid phase of the cement stone, and also by technological factors. The quantitative estimation of certain parameters is important for an approach to the understanding of the mechanism of frost attack and the choice of methods of its regulation for technological purposes. These are the temperature of pore liquid crystallization T f, the degree of freezing F d and the mass of ice I m formed during freezing. Examples of changes in ice formation parameters on variation of some of the technological factors are given.

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Abstract  

When exposed to attack by moisture, macroscopic defect-free materials (MDFs) undergo mass and phase changes. The nature of such changes was studied thermoanalytically. Attacked samples differ from non-attacked samples in the degradation of classical cement hydrates (TG, below 200C) and calcium carbonate (TG, DTA, 550-650C). Quantitative assessment favours the hypothesis of the impregnation/barrier effect due to the incorporation of polyphosphate glass into the structure of the MDFs. The identity of the thermal decomposition of attacked and non-attacked samples in the range 250-400C demonstrates the resistance of cross-linked sections of polymer and clinker constituents to the effects of moisture.

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Abstract  

This paper reports an experimental study on the magnesium sulphate resistance of mortar specimens incorporating 0, 10 and 20% of metakaolin (MK). The evidence of the attack was evaluated through the content of calcium hydroxide (portlandite) and formation of magnesium hydroxide (brucite) by thermal analysis (thermogravimetric and derivative thermogravimetric analysis). The mechanical degradation of the mortar specimens was evaluated through splitting tensile tests after 200 days of exposition to the magnesium solution. The addition of metakaolin resulted in a reduction in the content of calcium hydroxide and in a smaller formation of brucite in comparison with reference mixture. A tensile strength loss of about 7% was observed for the metakaolin mortars submitted to the magnesium solution attack for 200 days.

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Ignitability is one of the parameters that characterize the behaviour of building materials on flame action. The Ignitability Small Attack Flame fire test is used for the classification of building products by their reaction to fire. On the basis of the Ignitability fire test it can be determined that the tested material will be classified into the class E by reaction to fire. The Ignitability Small Attack Flame fire test precede the Single Burning Item fire test, that is used for classification of building products to class D, C, B, A2. The results of the Ignitability fire test were carried out as part of the research on the properties of gypsum composite with natural fiber reinforcement. As part of the research series of ignitability tests on two types of gypsum composite were carried out. The first type was a gypsum composite reinforced with straw fibres. The second type was composite reinforced with wooden fibres. Developed composite materials could be used in the future as board materials and therefore the determination of their fire parameters is a very important part of research. The results of the fire tests have shown that the developed material has a very good flame resistance.

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