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Otakar Bokůvka, Michal Jambor, Libor Trško, František Nový and Barbara Lisiecka

,9, 715. M iková , K. et al . 2013. Int. J. of Fatigue, 55, 33. S kočovský , P. et al . 2014. Náuka o materiáli. EDIS ŽU v Žiline. (in Slovak). T rško , L. et al . 2014. Dynamic Stength and Fatigue Lifetime, EDIS ŽU v Žiline. T rško , L. et al . 2014. Materials & Design, 57, 103. T rško , L. et al . 2017. J. of Mat. Eng. and Performance, 26, 6, 2784. U lewicz , R. M azur , M. Production Engineering Archives, No.1, 32.

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Ana Diana Ancas, M. Profire, I. L. Cirstolovean, M. Hornet and G. Cojocaru

Abstract

The lifetime of glass reinforced plastic pipes is 50 years. Extensive use of this type of pipe in its various applications, led to investigate their behavior in land that anthropogenic or natural causes, shows the different values of pH to neutral. The paper presents experimental results conducted on three samples of a PN SN10000 DN150 PN10 pipe buried in three different types of terrain: neutral, acidic, basic. They were subjected to axial load, measuring the force applied deformation force function. On the basis of the calculation formulas determined rigidity of the pipeline, the deformation speed of 50 mm / min. This concludes the type of land affects the rigidity of the pipe so its length of life decreases to that provided by suppliers in order to be taken compensatory measures in this regard such as choosing a higher class of pressure and stiffness pipeline than those arising discounted. This will allow for long-term value (50 years) in the mechanical characteristics sufficient for safe operation.

Open access

R. Grunvalds, A. Ciekurs, J. Porins and A. Supe

Abstract

In the research, measurements of polarisation mode dispersion of two OPGWs (optical ground wire transmission lines), in total four fibres, have been carried out, and the expected lifetime of the infrastructure has been assessed on the basis of these measurements. The cables under consideration were installed in 1995 and 2011, respectively. Measurements have shown that polarisation mode dispersion values for cable installed in 1995 are four times higher than that for cable installed in 2011, which could mainly be explained by technological differences in fibre production and lower fibre polarisation mode dispersion requirements in 1995 due to lack of high-speed (over 10 Gbit/s) optical transmission systems. The calculation methodology of non-refusal work and refusal probabilities, using the measured polarisation mode dispersion parameters, is proposed in the paper. Based on reliability calculations, the expected lifetime is then predicted, showing that all measured fibres most likely will be operational within minimum theoretical service life of 25 years accepted by the industry.

Open access

S.O. Pyskunov, Yu.V. Maksimyk and V.V. Valer

1 Introduction Structural elements of responsible objects function often under long-term static or cyclic force loading. The process of creep or fatigue, accompanied by the gradual accumulation of scattered damage, the formation and growth of macroscopic defects (fracture zones) are occurs under such a loading conditions. This problem, similarly as well as other aspects of reliability analysis [ 1 , 2 , 5 ], is very important for a reliable determination of long-term strength and lifetime. A description of above mentioned processes, which took the name

Open access

Melda Altikatoglu and Huriye Kuzu

Improvement of enzyme stability via non-covalent complex formation with dextran against temperature and storage lifetime

The optimal methodology to prepare the novel modified enzyme, polymer-enzyme complex, was developed to give a high catalytic activity in aqueous solution. The non-covalent complexes of two different enzymes (horseradish peroxidase and glucose oxidase) were prepared with various molar ratios (nD/nE 0,05; 0,1; 1; 5; 10; 15; 20) by using 75kDa dextran. The thermal stabilities of the obtained complexes were evaluated with the activities determined at different temperatures (25, 30, 35, 40, 50, 60, 70, 80°C) applying 60 minutes incubation time for pH 7. The complexes with the molar ratio nD/nHRP: 10 and nD/nGOD: 5 showed the highest thermal stability. Its activity was very high (ca. 1,5-fold higher activity than pure enzyme for HRP-dextran complexes) and almost the same between applying one hour incubation time and without incubation, and could also be measured at high temperatures (70, 80 °C). We finally succeeded in preparing dextran-enzyme complexes which showed higher activity than pure enzyme in aqueos solution at all temperatures for pH 7. In addition, the mentioned complexes at pH 7 had very long storage lifetime compared to purified enzyme at +4 °C; which is considered as a good feature for the usage in practice.

Open access

Gregor Izrael, Juraj Bukoveczky and Ladislav Gulan

Utilisation of Modeling, Stress Analysis, Kinematics Optimisation, and Hypothetical Estimation of Lifetime in the Design Process of Mobile Working Machines

The contribution deals with several methods used in the construction process such as model creation, verification of technical parameters of the machine, and life estimation of the selected modules. Determination of life cycle for mobile working machines, and their carrying modules respectively by investigation and subsequent processing of results gained by service measurements. Machine life claimed by a producer is only relative, because life of these machines depends not only on the way of work on that particular machine but also the state of material which is manipulated by the machine and in great extent the operator, their observance of security regulations, and prescribed working conditions.

Open access

Ioan Bondrea and Lucian Eugen Rosca

Abstract

The automotive industry faces future important changes through adoption of several new complex technologies like” X-by-wire” systems for vehicle dynamic control and high focus on green technology, fuel efficiency hybrids and electric vehicles. The implications of these technologies require in-depth understanding of the vehicle behavior during lifetime cycle, in order to reach a maximum optimized design. Therefore this paper introduces an analysis of a long-term capture data collection from a fleet of serial production vehicles in normal everyday use, as a solution to the lack of information available to describe the vehicle dynamics and load over the systems in a sufficient way. The analysis brings knowledge-based information, where before was difficult to answer and where statements were mainly based on subjective explanation. Results reveals important information describing load cycles during vehicle lifetime for different control events with focus on the braking events.

Open access

Zbigniew Sobek, Jolanta Różańska-Zawieja, Anna Nienartowicz-Zdrojewska and Beata Dybionka

References Agerholm J.S. B endixem C.,Andersen O.Arnbjerg J. (2001). Complex vertebral malformation in Holstein calves. J. Vet. Diagn. Inves., 13: 283-289. Antkowiak I. Pyllewski J. Dorynek Z. (2003). Lifetime production performance and the causes of culling of cows in the “Lubianka” fami (OHZ Lubiana) (in Polish). Anim. Prod. Rev. Pol. Soc. Anim. Prod. 68: 123-130. CRVNL (2013). [<https://www.crv4all.nl/>], last access date: 15-06-2013. CRVNL (2013). [<https://www.global.crv4all.nl/>], last

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Carmine Zoccali, Samar Abd ElHafeez, Evangelia Dounousi, Rossana Anastasi, Giovanni Tripepi and Francesca Mallamaci

. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: a report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines. Circulation. 2014; 129: S1-45. 11. Grams ME, Chow EK, Segev DL, Coresh J. Lifetime incidence of CKD stages 3-5 in the United States. Am J Kidney Dis. 2013; 62: 245-252. 12. Hoerger TJ, Wittenborn JS, Segel JE et al. A health policy model of CKD: 2. The cost-effectiveness of microalbuminuria screening. Am J

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Mareike Trauerstein, Sally E. Lowick, Frank Preusser and Heinz Veit

) using continuous wave OSL (CW-OSL) were conducted to identify the lifetime of the signal at varying temperatures for sample ABH09 and STH01. A set of 8 small aliquots (2 mm) per sample was first used for D e determination and then given a dose of ~100 Gy, followed by a preheat of 250°C for 10 s (as for D e determination). Similar to the approach of Buechi et al . (2017) , the aliquot was then held for various times, between 0 and 5000 s, at elevated temperatures of between 220 and 280°C, after which the remaining signal was measured, followed by a 20 Gy test dose