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EN
Purpose: The aim of this study was to determine the effect of bone mineral density (BMD) on the stress distribution in pelvic-hip complex (PHC) model which included bone structures and soft tissues. Bone mass changes in osteoporosis and osteopenia were considered in this analysis. In addition, the relations between force direction and stress distribution causing PHC fractures were determined. Methods: This paper presents the development and validation of a detailed 3D finite element model with high anatomical fidelity of the PHC and BMD changes in trabecular and cortical bones, modelled based on CT scans. 10 kN loading was induced on a model consisting of 8 ligaments, the pelvis, sacrum, femur in front and side directions. Results: For validation, the results of this model were compared to physiological stress in standing position and previous results with high-energy crashes under side impact load. Analysis of side-impact indicated the influence of BMD on femoral neck fractures, acetabular cartilage and sacroiliac joint delaminations. Front-impact analysis revealed the inferior pubic ramus, femoral neck fractures and soft tissue injuries, i.e., acetabular cartilage and symphysis pubis in osteoporosis and osteopenia. Conclusions: The elaborated PHC model enables effective prediction of pelvis injuries in high-energy trauma, according to Young-Burgess classification, and the determination of the influence of BMD reduction on pelvis trauma depending on force direction. The correlation between BMD and stress distribution causing varying injuries was determined.
PL
Utrzymywanie części liniowej infrastruktury przesyłowej w należytym stanie technicznym, zapewniającym odpowiedni poziom bezpieczeństwa, wymaga wykonywania szeregu czynności eksploatacyjnych. Wykorzystanie metody Magnetycznej Pamięci Metalu (MPM), a w szczególności Bezkontaktowej Magnetycznej Diagnostyki jest bardzo interesującym rozwiązaniem kontroli gazociągów. Głównym zastosowaniem badań są gazociągi nietłokowalne. W przemyśle gazowniczym widoczny jest wzrost zainteresowania tego typu metodami, ze względu na jej skuteczność oraz możliwość zastosowania badań BMD bez konieczności wykonywania prac ziemnych oraz jest alternatywą dla metod prognostycznych. W artykule przedstawiono przykłady wykorzystania metody MPM do badania gazociągów wysokiego ciśnienia wraz z przykładami wykrytych wad.
EN
Keeping the linear part of transmission infrastructure in proper technical condition, ensure an appropriate level of safety require performing a number of exploitation activities. The use of Metal Magnetic Memory (MPM) method, mainly Non-contact Magnetometric Diagnostics (NMD) is a very interesting solution for gas pipelines testing. The method is used primarily for unpiggable gas pipelines. In the gas industry can be seen a growing interest of use such methods, due to its effectiveness and applicability of NMD tests without the need for excavations and is an alternative to predictive methods. The article present the examples of using the Metal Magnetic Memory method for the high pressure gas pipelines testing with examples of detected defects.
3
Content available BMD ecofuel for diesel engines
EN
The World is strongly dependent on crude oil for its transport needs. In order to diminish this dependence, we need to introduce clean, CO2-efficient, secure and affordable transportation fuels. The current production of liquid biofuels in the EU25 is less than 1% of the market. Recent assessments have concluded that the 2010 targets, 18 Mtoe used in the transport sector, are unlikely to be achieved. There can be three basic possibilities of accomplishing this target: i) use of alcohols (first of all ethanol) and their mixing with petrol; ii) use of fatty acids esters (methyl or ethyl) of vegetable oils and their mixing with diesel fuel, iii) use of synthetic hydrocarbons of the synthetic gas coming from biomass resources and eventually their mixing with other "classical" hydrocarbons. This paper presents a novel way of utilizing alcohols as fuels for a diesel engine. It is proposed to use heavy alcohols as a mix with vegetable oils and conventional diesel fuel. It is presented the way to use alcohols. Namely, the use of heavy alcohols as a solvent for vegetable oil (named the biomix or BM) and after the obtainment of the thickness, which would be approximate to diesel fuel, mixing the biomix with diesel fuel to obtained biomixdiesel (BMD). This solution will be shown for example with butanol as heavy alcohol, rape oil as vegetable oil and conventional diesel fuel. The investigations are carried out with a simple diesel engine on the engine test bed. Main parameters of engine (power output, torque, specifically fuel consumption) and the main exhaust gas component (in this case CO, NOx, PM) will be investigated. There were better results achieved than one expected. Opposed to existing experiences, the maximum of power output and the torque of engine are higher in the whole range of the rotational speed of the engine crankshaft when the engine biomixdiesel (BMD) is reinforced. The addition of the component biomix to fuel influences the specific fuel consumption. Generally, with the larger part of the component biomix the specific fuel consumption grows. Because the power of engine also grows up one should expect that in exploitation the specific fuel consumption should not increase. Very important is that this fuel could be used to reinforce old, existing now and the future diesel engines. The production of butanol is known (from biomass and in other way with electrolysis of ethanol). The possibility to get butanol from ethanol gives a very good perspective for the use of ethanol from today's overproduction and moreover without the essential change of infrastructure. All this leads to the conclusion that fulfilling of the expected requirements of European Union regarding the ecofuels is fully possible.
4
Content available remote Relationship between BMD, apparent and ASH dunsity of human trabecular bone
EN
Trabecular bone is one of components of bone which quality is responsible for strength whole human bone. It is a porous structure, which change with age. In medical practise for estimation quality of bone the most often is used dual energy x-ray absorptiometry (DEXA). For scientific investigation of bones are often used apparent density and ash density. In the work presented results comparison values BMD, apparent and ash density obtained from measurement samples of human trabecular bone. Obtained values coefficient of determination R2 for relationship between this densities were in range 0,28÷0,62.
EN
BMD density, fractal dimension and volume tissue in volume of sample can be used to estimate the strength of trabecular bone. In the paper, presented is the comparison relations between the indicators for two groups of human trabecular bones – osteoporotic and coxarthrotic. Dependencies between the indicators were described with the determination coefficient R. Achieved values of the coefficient are contained in range 0,2÷0,56.
EN
The aim of this study was presented parameters of bone microstructure the method was based on the 2 dimensional FFT analysis, fractal dimension and analysis distribution histogram of intensity microradiographic image of trabecular bone microstructure. We compare all parameters with BMD using correlation analysis (Pearson’s linear correlation coefficient). We analysed 44 microradiograms of first metacarpal bone obtained from 44 postmenopausal women. For imagination we used microfocal x-ray tube (focus diameter 13µm, 25kV, magnification microradiograms was 5x, spatial resolution 40 pl/mm). Each study view was scanned in BMP format using 256 grey scale in 200x200 DPI scan resolution. Scan parameters was evaluated in each case used: parameters energy spectrum of 2D FFT, fractal dimension and image histogram parameters. All patients had standard QCT technique studies. We was high correlation between parameters of bone microstructure described by FFT energy spectrum and BMD - |r|=0,9285 (p<0,05). Correlation between fractal dimension and BMD was |r|=0,8529 (p<0.01). In analysis distribution histogram of intensity high correlation was between mean BMD - |r|=0,9435 (p<0.05).
PL
Tematem pracy jest przedstawienie korelacji parametrów opisujących mikrostrukturę kości gąbczastej pierwszej kości śródręcza z pomiarami BMD (bone mineral density) kręgosłupa wykonanymi metodą QCT. Mikrostrukturę opisano za pomocą następujących grup parametrów: grupa parametrów opisujących histogram obrazu, grupa parametrów opisujących widmo energetyczne dwuwymiarowej transformaty Fouriera obrazu rentgenowskiego struktury kostnej, wartość wymiaru fraktalnego badanego obrazu (FRDIM). Analizie poddano 44 obrazy mikroradiograficzne pierwszej kości śródręcza kobiet w wieku pomenopauzalnym. Do obrazowania mikrostruktury kostnej zastosowano mikroogniskową lampę rentgenowską. Otrzymane radiogramy przetwarzano do postaci cyfrowej przy użyciu skanera BMD pacjentek określono na podstawie badania QCT kręgosłupa. Otrzymano wysokie i bardzo wysokie korelacje parametrów opisujących stan mikrostruktury kostnej z BMD. Wśród parametrów opisujących histogram badanego obrazu najwyższą korelację z BMD wykazała wartość średnia histogramu - |r|=0,9435 (p<0,05). Dla wartości średniej widma energetycznego otrzymano wartość korelacji - |r|=0,9285 (p<0,05). Korelacja wymiaru fraktalnego z BMD wyniosła - |r|=0,8529 (p<0.01).
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