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Magdalena Sobczyńska, Tadeusz Blicharski and Mirosław Tyra

performance. Proc. 20th International Symposium “Animal Science Days”, 19-21.09.2012, Kranjska Gora, Slovenia, pp. 199-203. Gill P. (2007). Nutritional management of the gilt for lifetime productivity - feeding for fitness or fatness? Proc. London Swine Conference, 3-4.04.2007, London, Ontario, pp. 83-99. Hoge M.D., Bates R.O. (2011). Developmental factors that influence sow longevity. J. Anim. Sci., 89: 1238-1245. Holm B., Bakken M., Klemetsdal G., Vangen O. (2004). Genetic correlations between reproduction and production

Open access

Krzysztof Adamczyk, Wojciech Jagusiak and Joanna Makulska

References Adamczyk K., Pokorska J., Makulska J., Earley B., Mazurek M. (2013). Genetic analysis and evaluation of behavioural traits in cattle. Livest. Sci., 154: 1–12. Adamczyk K., Makulska J., Jagusiak W., Węglarz A. (2017). Associations between strain, herd size, age at first calving, culling reason and lifetime performance characteristics in Holstein-Friesian cows. Animal, 11: 327–334. Boichard D., Brochard M. (2012). New phenotypes for new breeding goals in dairy cattle. Animal, 6: 544–550. Buckley F., Lopez-Villalobos N., Heins B

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J. Vlček, D. Jančar, J. Burda, M. Klárová, M. Velička and P. Machovčák

Based on the operational measurement, of which content was to determine ladle thermal profile, there were analysed causes of possible damage of lining in steel ladles by steel breakout through the ladle shell. There exists connection between thermal state of ladle lining during the operation and its lifetime. There were reached to the conclusion that the cause of failure in the lining of ladle is except for high temperature of bath, also wide interval of temperature change during the tap operation, in consequence with possible insufficient pre-heating of ladle, discontinuous operation of aggregate and damage of insulating lining layer, respectively deformation of ladles shell.

Open access

D. Puiu, B. Corbescu and C. Cepisca

Abstract

The power cables passing through penetration leads to growth of the thermal ageing mechanisms rate. The paper presents the results of the laboratory tests when the real environmental service conditions for penetration are simulated comparison with the result of the thermal computation of the power cables heating and of the temperature influence evaluation of temperature increase of the power cable components on the cable lifetime. For this particular case, a power cable with PVC insulation, we estimated a lifetime decrease about 20 years referring to lifetime (30÷40 years) for location in air.

Open access

Jordan Hristov

. & Gwadera, M. (2012). On the application of an approximate kinetic equation of heat and mass transfer processes: the effect of body shape, Heat Mass Transfer , 48 (4), 599 -610. DOI: 10.1007/s00231-011-0905-6. 23. Rosner, D.E. (1969). Lifetime of a Highly Soluble Dense Spherical Particle1, The Journal of Physical Chemistry , 73 (2), 382-387. DOI: 10.1021/j100722a019. 24. Rice, R.G. & Do, D.D. (2006). Dissolution of a solid sphere in an unbounded, stagnant liquid, Chem. Eng. Sci ., 61 (2), 775-778. DOI: 10.1016/j.bbr.2011

Open access

P. Panek

Abstract

The influence of a p-type Si with different resistivity, charge carrier lifetime and emitter dopant impurities concentration on the crystalline silicon solar cells parameters were analyzed and experimentally checked. The findings were determined by quasi-steady-state photoconductance, current-voltage and spectral response methods. The study was accompanied by solar device simulation using a numerical PC1D program. The highest photoconversion efficiency of 15.13 % was obtained for the moncrystalline (Cz-Si) solar cell with a base resistivity of 1.8 Ωcm and an effective charge carrier lifetime of 22.9 μs. The results clearly confirmed the importance concerning the dopant level in a Si base material in relation to open circuit voltage and short circuit current possible to obtain from the solar cell. Reduction of a base material resistivtiy leads to a lower value of an effective charge carrier lifetime and photoconversion efficiency both for Cz-Si and multicrystalline (mc-Si) solar cells. The experimental results and calculation showed, that in the case of a solar cell produced on the basis of crystalline silicon, the most important spectral range for an efficiency of a cell is covering a wavelength range of 587 ÷ 838 nm.

Open access

Krystyna Kazimierowicz-Frankowska

Abstract

This paper focuses on a better understanding of the process of reflective cracking propagation through the pavement structure. A series of finite element numerical simulations were conducted to investigate the initial stress and strain states in typical semi-rigid pavements with and without reflective cracks under traffic loading. It was assumed that reflective-cracks propagate from the base layer to the pavement surface. The influence of selected parameters, such as the load position, overlay thickness, and subgrade quality on stress and strain concentrations was investigated. The behaviour of the pavement structure under repeated traffic loading was analyzed in terms of ground compaction. The original theoretical model proposed by Prof. Andrzej Sawicki was used to predict the deformation of a pavement subgrade subjected to traffic loading. The damaging effect of cracks appearing in the pavement structure was investigated. It was found that even a single crack in the pavement structure may significantly reduce the pavement lifetime.

Open access

József Horváth, Zsanett Tóth and Edit Mikó

persistency, female fertility, longevity, and lifetime profit index traits in Holstein dairy cattle, Journal of Dairy Science, 100 (2), 1246-1258. DOI: http://dx.doi.org/10.3168/jds.2016-11770 7. Holstein Association USA (2017). Genetic Evaluations for Productive Life, Somatic Cell Score and Net Merit Dollars, from http://www.holsteinusa.com/genetic_evaluations/ss_Gen_Eval_for_PL.html 8. Sewalem, A., Miglior, F., Kistemaker, G.J., Sullivan, P. & Van Doormaal, B.J. (2008), Relationship between reproduction traits and functional longevity in

Open access

JM Moore

Abstract

It is my distinct pleasure to make this presentation of the TSRC Lifetime Achievement Award to Dr Bill Collins from NC State University. Bill is well known in academic and industry circles for his contributions to Tobacco Science. Some have suggested that Bill Collins is the single person most identified with flue-cured tobacco at NC State and probably world-wide.

Open access

Michal Šajgalík, Andrej Czán, Juraj Martinček, Daniel Varga, Pavel Hemžský and David Pitela

Abstract

Machined surface is one of the most used indicators of workpiece quality. But machined surface is influenced by several factors such as cutting parameters, cutting material, shape of cutting tool or cutting insert, micro-structure of machined material and other known as technological parameters. By improving of these parameters, we can improve machined surface. In the machining, there is important to identify the characteristics of main product of these processes – workpiece, but also the byproduct - the chip. Size and shape of chip has impact on lifetime of cutting tools and its inappropriate form can influence the machine functionality and lifetime, too. This article deals with elimination of long chip created when machining of shaft in automotive industry and with impact of shape of chip-breaker on shape of chip in various cutting conditions based on production requirements.