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Peter Horbaj and Natália Jasminská

Analysis of Economical Efficiency of Low-Temperature Heating Utilization and HW Supply in Combination with Solar Collectors in Housing and Municipal Sphere

Economical system application of heat supply with using solar collectors in combination with heat pump is not only a question of return of investment. It is also the question of priorities, life style and ecology.

Many methods, studies and tables with presented data about energy consumptions for various ways of heating to determinate return of investment.

Basic condition of economical advantageousness of heat pump utilization instead of classic way of heat production in term of total year costs is that those are lower than total year costs for comparative classic way of heat production. Because difference in investment costs of comparative heating systems and heat pumps is almost always in the disadvantage of heat pump system.

Open access

Krzysztof Lejman and Rafał Fedorczuk

Abstract

The objective of the paper was to determine the level of circumferential stress in a wall of an open milk tank and to assess the tank wall degree of utilization according to the FKM Guideline calculation algorithm − Analytical Strength Assessment of Components, Made of Steel Cast Iron and Aluminium Materials in Mechanical Engineering. (German: FKM – Forschungskuratorium für Maschinenbau). The stress level in the tank wall was determined based on analytical calculations and numerical method using the FEA – Finite Elements Analysis. Numerical calculations were made in FEMAP with NX NASTRAN Solver (NASTRAN – NASA Structure Analysis). Similar stress values were found using two independent calculation methods. The difference between obtained stress values does not exceed 2%. Based on the FKM algorithm, the safety factor jges = 1.4 and static capacity of the tank wall ask = 19.7% were calculated.

Open access

Syed Omar Shah, Yu Kan Au, Fred Rincon and Matthew Vibbert

Abstract

Introduction: Acute ischemic stroke (AIS) is the fourth leading cause of death in the US. Numerous studies have demonstrated the use of comprehensive stroke units and neurological intensive care units (NICU) in improving outcomes after stroke. We hypothesized that an expanded neurocritical care (NCC) service would decrease resource utilization in patients with LHI.

Methods: Retrospective data from consecutive admissions of large hemispheric infarction (LHI) patients requiring mechanical ventilation were acquired from the hospital medical records. Between 2011-2013, there were 187 consecutive patients admitted to the Jefferson Hospital for Neuroscience (Philadelphia, USA) with AIS and acute respiratory failure. Our intention was to determine the number of tracheostomies done over time. The primary outcome measure was the number of tracheostomies over time. Secondary outcomes were, ventilator-free days (Vfd), total hospital charges, intensive care unit length of stay (ICU-LOS), and total hospital length of stay (hospital-LOS), including ICU LOS. Hospital charges were log-transformed to meet assumptions of normality and homoscedasticity of residual variance terms. Generalized Linear Models were used and ORs and 95% CIs calculated. The significance level was set at α = 0.05.

Results: Of the 73 patients included in this analysis, 33% required a tracheostomy. There was a decrease in the number of tracheostomies undertaken since 2011. (OR 0.8; 95% CI 0.6-0.9: p=0.02).

Lower Vfd were seen in tracheostomized patients (OR 0.11; 95%CI 0.1-0.26: p<0.0001). The log-hospital charges decreased over time but not significantly (OR 0.9; 95%CI 0.78-1.07: p=0.2) and (OR 0.99; 95%CI 0.85-1.16: p=0.8) from 2012 to 2013 respectively.

The ICU-LOS at 23 days vs 10 days (p=0.01) and hospital-LOS at 33 days vs 11 days (p=0.008) were higher in tracheostomized patients.

Conclusion: The data suggest that in LHI-patients requiring mechanical ventilation, a dedicated NCC service reduces the overall need for tracheostomy, increases Vfd, and decreases ICU and hospital-LOS.

Open access

Zuzana Kováčiková, Vladimíra Vargová and Milan Michalec

, M. - SZAKOVÁ, J. - SCHELLBERG, J. - TLUSTOŠ, P. 2010. The Rengen Grassland Experiment : relationship between soil and biomas chemical properties, amount of elements applied, and their uptake. In Plant Soil , vol. 333 , 2010, no. 1-2, pp. 163-179. DOI: 10.1007/s11104-010-0332-3 HOLÚBEK, R. - JANČOVIČ, J. - GREGOROVÁ, H. - NOVÁK, J. - ĎURKOVÁ, E. -VOZÁR, Ľ. 2007. Krmovinárstvo - manažment pestovania a využívania krmovín [Forage production - management of crop-growing and utilisation] 1. vyd. Nitra : SPU, 2007. 420 pp. ISBN 978

Open access

Andrzej Adamkiewicz and Wojciech Zeńczak

Abstract

Heavy oils (HFO fuels) used on ships play a part in degradation of technical condition of heat exchange surfaces of utilization boilers especially on the exhaust gas side. Presence of sulphur in these fuels is the main factor favouring degradation. The upper limit for sulphur content in the fuel used outside the SECA areas equal to 3.5% is currently in force, at least until the year 2020 or 2025. The recommended by classification societies overhauls of utilization boilers are, therefore characterized by a specially chosen strategy thanks to which it is possible to maintain their appropriate technical condition. The requirement to use fuels with low sulphur content (LSFO), which are significantly more expensive than MDO fuels, in the areas of controlled sulphur emissions also led to a further introduction of alternative fuels, such as methanol and above all liquefied natural gas (LNG), onto ships. That is especially valid for the ship owners whose vessels e.g. ferries sail mainly within SCECA This article analyses the consequences of the introduced fuel change on utilization boiler maintenance. A change in the technical condition maintenance strategy for utilization boilers has been suggested.

Open access

Jerzy Myszkowski, Eugeniusz Milchert, Marcin Bartkowiak and Robert Pełech

References Milchert, E. (1997). Technologies of the production of chloroorganic compounds. Waste utilization. Szczecin, WUPS. (in Polish) Milchert, E., Bartkowiak, M., Pełech, R. (2008). Progress in selected technologies of chemical industry. Szczecin, WUPS. (in Polish) Pełech, R., Milchert, E. & Wróbel, R. (2006). Adsorption dynamics of chlorinated hydrocarbons from multi-component aqueous solution onto activated carbon. J. Hazard. Mater. 137, 1479-1487. DOI: 5551 10.1016/j

Open access

Di Jin, Shengguo Zhao, Nan Zheng, Yves Beckers and Jiaqi Wang

. Dairy Sci., 66: 2597-2601. Kim J.N., Henriksen E.D., Cann I.K., Mackie R.I. (2014). Nitrogen utilization and metabolism in Ruminococcus albus 8. Appl. Environ. Microb., 80: 3095-3102. Kim M., Morrison M., Yu Z. (2011). Status of the phylogenetic diversity census of ruminal microbiomes. FEMS Microbiol. Ecol., 76: 49-63. Kohn R., Dinneen M., Russek-Cohen E. (2005). Using blood urea nitrogen to predict nitrogen excretion and efficiency of nitrogen utilization in cattle, sheep, goats, horses, pigs, and rats. J. Anim. Sci

Open access

Martin Užík and Alžbeta Žofajová

levels. In Crop Science, vol. 42, pp. 1129−1134. MOLL, R.H. - KAMPRATH, E.J. - JACKSON, W.A.1982. Analysis and interpretation of factors which contribute to efficiency of nitrogen utilization. In Agronomy Journal , vol. 74, pp. 562-564. ORTIZ-MONASTERIO, J.I.R. - SAYRE, K.D. - RAJARAM, S. - McMAHON, M. 1997. Genetic progress in wheat yield and nitrogen use efficiency under four nitrogen rates. In Crop Science, vol. 37, pp. 898−904. RAUN, W.R. - JOHNSON, G.V. 1999. Improving nitrogen use efficiency for cereal production

Open access

Mariusz Matejski and Tadeusz Graczyk

.: Abyssal vehicles - utilisation, maintenance, system management, International Scientific Conference "The Transport of the 21st Century", Technological University of Warsaw - Faculty of Transportation, National Academy of Sciences - Transport Committee, Warsaw, 20-22 September 2004. 7. Olejnik A.: The current state of technique of remotely controlled abyssal vehicles. Polish Hyperbaric Research, Nr 3 (28) 2009, pp. 23-46.

Open access

Marie Štýbnarová, Aleš Dufek and Rémy Delagarde

Abstract

The aim of this study was to evaluate changes in floristic composition of permanent grasslands after the cessation of their regular utilisation and organic fertilisation. A long-term small plot trial was established in 2004 in locality Rapotín. During 2004-2012, the experiment was fertilised with compost and slurry, both with the range of stocking rates 0.9, 1.4 and 2.0 livestock units (LU)/ha (corresponding to 54, 84, and 120 kg N/ha). The plots were cut 2-4 times per year depending on given dose of fertiliser. During 2013‒2016, the regular management was ceased and the grasslands were completely abandoned. Before the grassland abandonment, the highest total number of species (24 species) was found in the treatments regularly fertilised with compost. The dominance of grasses was influenced by the grassland management, with decreasing intensity of utilisation, the dominance of grasses increased. Four years after the grassland abandonment, the species diversity in almost all treatments decreased and the dominance of grasses increased in all treatments, up to the value 67-80%. Based on the data about the soil chemical parameters from two investigated years, our results suggested not only the effect of grassland management and its subsequent abandonment, but also a residual effect of the both organic fertilisers. These findings indicated the importance of the maintenance of regular grassland management for sustainable conservation of grassland communities.