Search results for " CRA"

DEVELOPMENT OF AN ANTHROPOMORPHIC MODEL FOR VEHICLE – PEDESTRIAN CRASH TEST

2009

The purpose of this work is the achievement of an anthropomorphic model for the virtual simulation of pedestrian – vehicle crash test. “Dummy” construction in Visual Nastran room does possible the preparation of crash test with several vehicle models. Its three-dimensional geometry is implemented by video animation software, extracting the geometry element for element, and its characteristics are in keeping with EURONCAP protocol. Every bodily segment properties are determined using the reference material on the movement biomechanics. At last fall tests from three different heights are simulated for the “Dummy” validation, obtaining a reliable result.

Power-Laws hereditariness of biomimetic ceramics for cranioplasty neurosurgery

2019

Abstract We discuss the hereditary behavior of hydroxyapatite-based composites used for cranioplasty surgery in the context of material isotropy. We classify mixtures of collagen and hydroxiapatite composites as biomimetic ceramic composites with hereditary properties modeled by fractional-order calculus. We assume isotropy of the biomimetic ceramic is assumed and provide thermodynamic of restrictions for the material parameters. We exploit the proposed formulation of the fractional-order isotropic hereditariness further by means of a novel mechanical hierarchy corresponding exactly to the three-dimensional fractional-order constitutive model introduced.

Sedimentation properties of chitosomal chitin synthetase from the wild-type strain and the 'slime' variant of Neurospora crassa.

1989

Marked differences in the pattern of sedimentation of cellular structures were observed after isopycnic centrifugation of crude cell-free preparations from the Neurospora crassa wall-less 'slime' variant and mycelial wild-type strain. Kinetic studies of particle sedimentation showed that the various types of subcellular components, as revealed by turbidity, UV absorption, polypeptide patterns, and chitin synthetase activity determinations, sediment independently of one another. An important feature was the finding that chitin synthetase from 'slime' peaked at a median specific gravity of 1.1201 +/- 0.0036, whereas that from wild-type strain sedimented at a higher buoyant density (specific g…

Spuścizna pisarska biskupa Franciszka Jopa (1897-1976)

2016

Obchodzona w 2016 r. 40. rocznica śmierci bpa Franciszka Jopa skłoniła środowisko historyków Kościoła oraz duchowieństwo i wiernych Śląska Opolskiego do licznych inicjatyw, mających na celu upamiętnienie pierwszego biskupa opolskiego. Niniejszy tekst poświęcony jest spuściźnie pisarskiej bpa Jopa. Autor, przy pomocy wcześniejszych opracowań, wskazuje na spis 357 pozycji pisarskich pasterza, jakie zamieszczono w 1978 r. w „Studiach Teologiczno-Historycznych Śląska Opolskiego”. Spis ów uzupełnia o 6 kolejnych tekstów, będącymi przemówieniami i pisemnymi opiniami pasterza, jakie wygłosił lub przesłał na piśmie w czasie Soboru Watykańskiego II, a które wydrukowane zostały w Acta Synodalia sacro…

Physiological and agonistic behavioural response of Procambarus clarkii to an acoustic stimulus

2012

Summary This study examined the effects of an acoustic stimulus on the haemolymph and agonistic behaviour of the red swamp crayfish Procambarus clarkii. The experiment was conducted in a tank equipped with a video recording system using 6 groups (3 control and 3 test groups) of five adult crayfish (30 specimens in total). After one hour of habituation, the behaviour of the crayfish was monitored for two hours. During the second hour, the animals in the test groups were exposed to a linear sweep (frequency range 0.1-25 kHz; peak amplitude 148 dBrms re 1 µPa at 12 kHz) acoustic stimulus for 30 minutes. Exposure to the noise produced significant variations in haemato-immunological parameters a…

Profiling the physiological and molecular response to sulfonamidic drag in Procambarus clarkii

2014

Sulfamethoxazole (SMZ) is one of the most widely employed sulfonamides. Because of the widespread use of SMZ, a considerable amount is indeed expected to be introduced into the environment. The cytotoxicity of SMZ relies mainly on arylhydroxylamine metabolites (S-NOH) of SMZ and it is associated with the production of reactive oxygen species (ROS). There is limited information about the toxic potential of SMZ at the cellular and molecular levels, especially in aquatic and/or non-target organisms. In the present study, the red swamp crayfish (Procambarus clarkii), being tolerant to extreme environmental conditions and resistant to disease, was used as a model organism to profile the molecula…

Experimental investigations on a model of cryogenic edema.

1987

The role of mechanisms underlying formation and progression of vasogenic brain edema is investigated. On this purpose, cerebral edema was produced by cortical freezing in two different brain situations in rabbits (with or without replacement of bone flap). BBB (Blood-Brain Barrier) breakdown was evaluated by observation of Evans blue extravation, while a histopathological evaluation was carried out by light and transmission electron microscopy. Water content of brain tissue was determined by the wet/dry weight ratio method. Comparison of extension and intensity of cerebral edema between these two groups of animals shows a statistically significant difference: there was evidence of higher wa…

The mechanically-based approach to 3D non-local linear elasticity theory: Long-range central interactions

2010

Abstract This paper presents the generalization to a three-dimensional (3D) case of a mechanically-based approach to non-local elasticity theory, recently proposed by the authors in a one-dimensional (1D) case. The proposed model assumes that the equilibrium of a volume element is attained by contact forces between adjacent elements and by long-range forces exerted by non-adjacent elements. Specifically, the long-range forces are modelled as central body forces depending on the relative displacement between the centroids of the volume elements, measured along the line connecting the centroids. Further, the long-range forces are assumed to be proportional to a proper, material-dependent, dis…

3D boundary element analysis of delamination crack using the Modified Crack Closure Integral

2012

Structural Health Monitoring of delaminated composite structures by the Boundary Element method

2012

Structural Health Monitoring (SHM) for composite materials is becoming a primary task due to their extended use in safety critical applications. Different methods, based on the use of piezoelectric transducers, strain memory alloys as well as of fibre optics, has been successfully proposed to detect and monitor damage in composite structural components with particular attention focused on delamination cracks. In the present paper a Structural Health Monitoring model based on the use of piezoelectric sensors, already proposed by the authors for isotropic damaged components, is extended to delaminated composite structures. The dynamic behavior of the host damaged structure and the bonded piez…