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Jerusalem Artichoke as a Means of Fields Conservation

varietes de topinambour (Helianthus tuberosus L.) en conditions naturelles. In Evolution physiologique et conservation des tubercules durant la periode hivernale. Limoges, France : These Universite Limoges, 1987. Mimiola, G. 1988. Test of topinambour cultivation in southern Italy. In Topinambour (Jerusalem artichoke), Report EUR 11855, Grassi, G. and Gosse, G., Eds., Commission of the European Communities, Luxembourg, 1988, pp. 53-60. Shahgholi, H. - Makarian, H. - Shokati, B. - Talaei, G. H. - Asgharipour, M. R. 2015. Do tillage methods

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Impact of conservation practices on runoff and soil loss in the sub-humid Ethiopian Highlands: The Debre Mawi watershed

water conservation activities in the Chemoga watershed, Blue Nile basin, Ethiopia. Land Degradation and Development, 13, 189-200. Bosshart, U., 1995. Catchment Discharge and Suspended Sediment Transport in the Highlands of Ethiopia and Eritrea, Ph.D. Thesis,University of Berne, Switzerland. Constable, M., Belshaw, D., 1986. The Ethiopian highlands reclamation study: major findings and recommendations. ONCCP (Office of the National Committee for Central Planning). Towards a food and nutrition strategy for Ethiopia: Proceedings of the

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The effect of soil surfactants on soil hydrological behavior, the plant growth environment, irrigation efficiency and water conservation

: Water conservation on fairways by systematic injection of wetting agents. California Fairways. July/August, 14 , 4, p. 11-12, 14-16. MITRA S., VIS E., KUMAR R., PLUMB R., FAM M., 2006: Wetting agents and cultural practices increase infiltration and reduce runoff losses of irrigation water. Biologia, Bratislava, 61 /Suppl., 19, S353-S357. MORGAN W. C., LETEY J., RICHARDS S. J., VALORAS N., 1966: Physical soil amendments, soil compaction, irrigation, and wetting agents in turfgrass management I. Effects on

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Evaluation Of Onion Production On Sandy Soils By Use Of Reduced Tillage And Controlled Traffic Farming With Wide Span Tractors

Journal of Soil Science, vol. 31, no. 2, pp. 155–173. CAMPIGLIA, E. – MANCINELLI, R. – RADICETTI, E. 2011. Influence of no-tillage and organic mulching on tomato ( Solanum lycopersicum L.) production and nitrogen use in the mediterranean environment of central Italy. In Scientia Horticulturae, vol. 130, no. 3, pp. 588–598. CARTER, M. R. – SANDERSON, J. B. – PETERS, R. D. 2009. Long-term conservation tillage in potato rotations in Atlantic Canada: Potato productivity, tuber quality and nutrient content. In Canadian Journal of Plant Science, vol. 89, no. 2

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Identifying Vehicle and Collision Impact by Applying the Principle of Conservation of Mechanical Energy

Abstract

Various methodologies and tools applied to identification of vehicle and collision impact seek to present more and more accurate solutions to reproduce, restore, recreate and investigate the casualty. Modern computer technology and software provide the tools to solve specific problems developing mathematical modelling of complex mechanical systems involving vehicles and other objects in a road accident. Scientists generally utilize the Standard Test Method for Impact Testing calculating the energy of deformation of both vehicles, however, one of its limitations is the evaluation of the kinetic energy of the vehicles in post-collision taking into consideration vehicle rotation and linear displacement. To improve the analysis, dynamic traffic simulation is used, taking into account the variations in the coefficient of friction, suspension elasticity and damping. The proposed method is based on a system of two equations derived from two principles: the Principle of Conservation of Mechanical Energy and the Principle of Conservation of Momentum in the impact phase. The new approach is conducted on mathematical modelling and computer simulation of vehicle motion after the impact, wherefrom the linear and angular velocities are analysed. This is achieved by the numerical solution of the differential equations of motion of the cars after the impact, and the given initial conditions that satisfy the solution are used to solve the system of equations. The main findings of the study can be grouped as follows: 1) The positions of the vehicles prior to the moment of first impact and the post-impact orientation of velocity vectors are more precise. 2) The variability of the tire-road friction coefficient is taken into consideration. 3) The value of coefficient of restitution according to Newton’s theory of impact is unnecessarily determined.

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Thermo-economic approach for absorption air condition onboard high-speed crafts

., Collins, W.J., Corbett, J.J., Endresen, O., Grainger, R.G., Moldanova, J., Schlager, H. and Stevenson, D.S., 2009. Transport impacts on atmosphere and climate: Shipping . Atmospheric Environment, doi: 10.1016/j.atmosenv.2009.04.059. Florides, G.A., Kalogirou, S.A., Tassou, S.A. and Wrobel, L.C., 2003. Design and construction of Li-Br-water absorption machine. Journal of Energy conservation and management , [e-journal] 44, pp.2483-2508, Available through: King Abdul-Aziz University Library website <http://library.kau.edu.sa> [Accessed 27 October 2011

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Fully nonlinear time-domain simulation of a backward bent duct buoy floating wave energy converter using an acceleration potential method

ABSTRACT

A floating Oscillating Water Column (OWC) wave energy converter, a Backward Bent Duct Buoy (BBDB), was simulated using a state-of-the-art, two-dimensional, fully-nonlinear Numerical Wave Tank (NWT) technique. The hydrodynamic performance of the floating OWC device was evaluated in the time domain. The acceleration potential method, with a full-updated kernel matrix calculation associated with a mode decomposition scheme, was implemented to obtain accurate estimates of the hydrodynamic force and displacement of a freely floating BBDB. The developed NWT was based on the potential theory and the boundary element method with constant panels on the boundaries. The mixed Eulerian-Lagrangian (MEL) approach was employed to capture the nonlinear free surfaces inside the chamber that interacted with a pneumatic pressure, induced by the time-varying airflow velocity at the air duct. A special viscous damping was applied to the chamber free surface to represent the viscous energy loss due to the BBDB’s shape and motions. The viscous damping coefficient was properly selected using a comparison of the experimental data. The calculated surface elevation, inside and outside the chamber, with a tuned viscous damping correlated reasonably well with the experimental data for various incident wave conditions. The conservation of the total wave energy in the computational domain was confirmed over the entire range of wave frequencies.

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The Research of Historical Trusses in Northern Regions of Slovakia

Abstract

The blanket research of historical trusses in the territory of Slovakia has been running at our department since 2008. This research is done as teamwork in cooperation with experts from the field of conservation, and it is mainly focused on typology, construction, and the current technical and constructional state of investigated trusses. The long-time support of the grant scheme from the Ministry of Culture allows to get a fair amount of different data related to individual buildings and structures, which enables to carry out the in-depth research. In terms of their conservation and maintenance with an effort to extend their lifetime (the oldest known historical trusses in Slovakia are those of the 13th century), it is necessary to look into the microclimate impact of the under-roof space on wooden roof structures as well as to monitor the contemporary constructional and technical condition of a roof structure itself. The suitable microclimate in the under-roof space is influenced by a number of marginal conditions, constructional solutions of roof details, proper space ventilation etc

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CFD Proposals for the Layout of Air Vents for Realization of Underfloor Air Cavity Created from Special Fittings

References [1] Benža et al. (1998) Folk architecture and urban planning of rural settlements in Slovakia . Bratos;ava: Academic Electronic Press, s. r. o. for National Conservation and Landscape Center. [2] http://www.geoplast.it/eng/edilizia/modulo-system/index.html [3] STN 73 0540-2. (2012). Thermal protection of buildings. Thermal performance of buildings and components. Part 2: Functional requirements. Slovak Republic. [4] STN 73 0540-3. (2012). Thermal protection of buildings. Thermal performance of buildings and components

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Effect of mineral additives on structure and properties of concrete for pavements

Engineering Transactions , vol. 25, 2011, p. 297-302. [4] Targan S., Olgun A., Erdogan Y., Sevinc V. Effects of supplementary cementing materials on the properties of cement and concrete, Cement Concrete Research , vol. 32, 2002, no 10, p. 1551–1558. [5] Sanytskyy M.A., Sobol Kh.S., Markiv T.V. [Modified composite cements] . Lviv Polytechnic National University Publishing House, Lviv, 2010. [In Ukrainian]. [6] Shi, C., & Qian, J. High performance cementing materials from industrial slags—a review. Resources, Conservation and Recycling , vol.29, 2000, no

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