a review - Acta Technica Corviniensis

ACTA TECHNICA CORVINIENSIS – Bulletin of Engineering
both gasoline fuel and CNG. The accuracy of the model was verified using experimental results of the engine testing
showing good agreement between the model and the real engine. As a result, predictions are obtained that provide a
detailed picture of engine performance condition with different fuel. In addition, two different turbochargers has been
added to intake system and the engine performance characteristics like efficiency, net power and fuel consumption
compared to CNG and gasoline engines without turbocharger. As a result, according to engine results and compressor
characteristics a turbocharger was select for the based CNG engine.
17. István BÍRÓ – HUNGARY
SIMPLE NUMERICAL METHOD FOR 2-DOF PLANAR KINETICAL PROBLEMS 109
Abstract: The motion analysis is an important field in the education of mechanical engineers. Kinematical and kinetical
analysis of rigid bodies linked to each other by different constraints (mechanical systems) leads to integration of second
order differential equations. In this way the kinematical functions of parts of mechanical systems can be determined.
The degrees of freedom of the mechanical system increase as a result of the application of elastic parts in it. Numerical
methods can be applied to solve such problems. A simple numerical method will be demonstrated by author by the aid
of several examples. Some parts of results obtained by using the numerical method were checked by analytical way. The
published method can be used in the technical higher education
18. Jan KMEC - SLOVAKIA
SAFE WORKING CONDITIONS FOR THE WATER JET TECHNOLOGY 113
Abstract: Water-jet cutting technology provides new possibility to shape cutting and various material cold cutting
without heat influence of material on cutting edge. However, the power of the water jet overcomes expectation of a
people that are not familiar with the technology. Work safety with water-jet in various production technologies must
make provision for not only safety work with water-jet technology, but also safety work with all devices, which are on
that workplace situated and also material manipulation. So, the paper is focused on some of the safety aspects at the
water-jet workplaces.
19. G. ADEDOKUN, J.A. OLADOSU, T. K. AJIBOYE – NIGERIA
SMALL HYDRO POWER POTENTIAL CAPACITY ESTIMATION FOR PROVISION OF RURAL
ELECTRICITY IN NIGERIA 117
Abstract: Nigeria’s electricity demand increases due to growth in industrialization and socioeconomic weight.
Regrettably, power industry of the country has not been able to satisfy the need of their customers. Therefore, if the
country is to meet its energy demand alternative sources of power generation are very essential. Opportunities abound
in hydropower scheme development as a viable energy source of electricity which will curtail and minimize greenhouse
gases and emissions into environment. Meanwhile, there are small rivers all over the country with potential sites
suitable for small hydropower scheme, development of which will ensure the supply of electricity to remote
communities. This can be used as a substitute for commercial fuels, which effect reduce cost of fuelling and raise the
earning potential of the rural communities.
20. Cristina HORA, Simona DZIŢAC, Călin SECUI, Gabriel BENDEA – ROMANIA
RELIABILITY ANALYSIS OF SPHERICAL VALVE (VS) FROM HPP REMEŢI USING MONTE CARLO
SIMULATION 121
Abstract: In every hydro energetic arrangement, the water approaches, in differently construction elements and trough
them, are equipped with valves. These valves assure the normal functioning of equipments, respectively there
operatively insulation in case of failures or repairs. Also, the reliability level of hydro mechanical equipments can have
a major impact on the operational reliability of HPP (Hydro Power Plants). In consequence, there are justified the
concerns regarding the predictive reliability of them. In this paper, these studies of hydro-mechanical equipments
reliability are made using the Monte Carlo simulation.
21. József CSANÁDI, Cecilia HODÚR, József FENYVESSY – HUNGARY
THE PROBLEM OF THE DETERMINATION OF WATER AND COW MILK ADULTERATING GOAT
MILK 125
Abstract: The demonstrability of the adulteration of goat milk with added water and cow milk was investigated by
measurement of the freezing point of the milk. Milk samples collected from a Saanen goat flock were mixed with water
in the ranges 0-90% and 1-10% and with cow milk in the ranges 0-90%. The freezing points of the samples were
determined by a standard cryoscopic method. Our results suggested that the freezing point prescribed as a reference
value by the Codex Alimentarius Hungaricus and the EU directives for fresh and unadulterated goat milk (-0.52 °C) is
too liberal, and this opens the door for the adulteration of goat milk. Only extraneous water in excess of 6% could be
detected reliably in goat milk and therefore the measured freezing points at lower extraneous water contents appear
falsely as good results. Accordingly, revision of the reference freezing point value of goat milk seems reasonable.
Similarly, demonstrated that the adulteration of goat milk with cow milk can not be proved by measurement of the
freezing point unless the goat milk contains cow milk in excess of 50%.
22. Mohammed Ali I. AL-HASHIMI, Manar M. AL-SAFAR – IRAQ
REMOVAL OF CADMIUM FROM SYNTHETIC WATER BY USING AGRICULTURAL WASTES 131
Abstract: Heavy metals are among the most toxic contaminants of surface water. The main sources of toxic metals are
industrial wastes from processes such as electroplating, metal finishing, chemical manufacturing, and nuclear fuel
processing. Since most of heavy metals are non degradable into nontoxic metals end products, these concentration must
be reduced to acceptable levels before discharged them into environment. The goal of this research Examine the ability
of different media to reduce the concentration of cadmium ions in aqueous solution. The application of low-cost
adsorbents obtained from plant wastes as a replacement for costly conventional methods of removing cadmium ions
from waste water has been reviewed. Langmuir and Freundlich adsorption isotherms were applicable to the absorption
process and their constants were evaluated. The single component adsorption of heavy metal ions named Cadmium (II)
onto powdered activated carbon (PAC), karab, rice husks and corncobs from water aqueous solution has been
investigated in batch. The multiple correlations simulated the experimental data of the batch tests, and regression
equations were found for (PAC), karab, rice husks and corncobs with correlation coefficient for each media: 0.984,
18
2013. Fascicule 2 [April–June]