EVALUATION OF THE CREEP OF ROCKS ON THE BASIS OF RHEOLOGICAL MATERIAL MODEL

The paper shows a possible method for the evaluation of creep experiments carried out in the rock-physical laboratory of the Department of Mineralogy and Geology of the Budapest Technical University, by which the rheological material characteristics needed for the dimensioning of constructions in rock environments built of elastic rocks can be determined

Compressive load bearing and bone architecture of lumbar vertebrae in terms of sex and aging

Relation between vertebral compressive strength and trabecular architecture is presented in terms of aging and sex. Complex in vitro medical-engineering analysis of cadaver human lumbar L1 and L2 vertebrae was executed: densitometry, CT, MRI, mechanical test and histology, in aspect of osteoporosis. In this paper the results of the mechanical test are detailed only. The compressive mechanical parameters, like limit stress and strain, proportional stress and strain, Young modulus, ductility, energy absorption capacity were determined. Morphometry analysis was based on the CT pictures. Density and diameter of trabeculae were measured. Correlation between morphometric and mechanical properties was evaluated in terms of aging, sex and bone mineral density

THE GENERAL SPATIAL SYSTEM OF ROCKY ENVIRONMENT FOR BUILDING PURPOSES

The paper summarizes and methodizes the necessary civil engineering knowledge for the consideration of interaction between the construction and its rocky environment planned from the point of view of both the construction and the earth's crust region. The rocky environment of the construction has been formed under natural conditions. This determines its properties. Models constructed by the selection of earth's crust elements of uniform properties and by carrying out the necessary and possible generalizations serve to eyaluate the interactions

FRACTURE MECHANICAL ANALYSIS OF HUMAN SKULL

We provide, in this work, estimation of critical value of stress intensity factor of the human skull (KIC). Our research assists examinations concerning dynamic effects exerted on human skull (cracks, etc.)

Stress sensitivity of correlation between POD and PPO activities in plants

In the leaf extracts of two plant species (Quercus robur L. and Phaseolus vulgaris L.),peroxidase (POD) and polyphenol oxidase (PPO) activities have been measured by the methods ofShannon et al (1966) and Flurkey and Jen (1978). The oxidative activities regarded as semi-empiricalbiochemical variables have distributions in the plant foliage and between them a linear correlation hasbeen observed. In this work the resultant oxidative activities of POD and PPO isoenzymes of plantfoliages, the measuring uncertainties of their values and their correlation are interpreted. For theeffects of cold shock and lack of illumination, significant alterations in the correlation have beenrevealed that are also reflected by the parameters of the regression. The correlation of POD and PPOhas been established to be stress sensitive by the application of covariance analysis (ANCOVA)