Determination of the equivalent torsional vibration system

U radu je prikazan postupak zamene elemenata kompleksnog torzionooscilatornog sistema brodske dizelmotorne propulzije uprošćenim ekvivalentnim elementima istih dinamičkih karakteristika. Izloženi postupak sadrži metode za određivanje ekvivalentnih dužina, krutosti i momenata inercije na osnovu jednakosti kinetičkih i potencijalnih energija realnih i ekvivalentnih elemenata sistema. Osim toga, analizirani su pobudni momenti koji izazivaju prinudne torzione oscilacije razmatranog sistema.The procedure of replacing the elements of a complex torsional vibration system of ship diesel engine propulsion with simplified equivalent ones with the same dynamic characteristics is shown in this work. The given procedure comprises the methods for the determination of equivalent lengths, stifnesses and moments of inertia based on the equality between kinetic and potential energy of real and equivalent elements of the system. Additionally, the exciting moments which excite forced torsional vibrations of the considered system are analysed

Free vibration of structures composed of rigid bodies and elastic beam segments

Free vibration of structures composed of rigid bodies and elastic beam segments is considered, assuming that the mass centers of rigid bodies are not located on the neutral axes of undeformed elastic beam segments. It is assumed that the rigid bodies of the system perform planar motion in the same plane and that their mass centers are located in that plane. The elastic beam segments are treated as the Euler-Bernoulli beams. In order to determine natural frequencies of the system, modification of the conventional continuous-mass transfer matrix method has been clone. The order of the overall transfer matrix has been reduced by this modification. Theoretical considerations are accompanied by two numerical examples.This is the peer reviewed version of the article: Obradović, A.; Šalinić, S.; Trifković, D.; Zorić, N.; Stokić, Z. Free Vibration of Structures Composed of Rigid Bodies and Elastic Beam Segments. Journal of Sound and Vibration 2015, 347, 126–138. [https://doi.org/10.1016/j.jsv.2015.03.001

ADVANCED FEATURES OF THE RECONSTRUCTED SPECIAL PURPOSE RIVER SHIP "KOZARA" WITH A DIESEL ELECTRIC DRIVE (DED)

The reasons, reconstruction and some characteristics of the special purpose river ship BPN-30 "Kozara" are presented in this paper. The ship is equipped with two diesel aggregate power of 400 kW each, which drive two electric motors power of 250 kW each, bow thruster power of 90kW and supply ship electrical grid with power of 90 kW. Main diesel electric generators can operate independently or in parallel operation. On board the auxiliary diesel aggregate is set to supply the ship with electricity with the power of 70 kW while on shore connection. The performed testing of the ship show a significant improvement of the manoeuvring and propulsion characteristics of the ship compared to conventional diesel-powered two engines, rated power 294,4 kW each. The paper outlines other advantages of the ship with electric propulsion as it increases in the comfort of the crew and downstream economical cruising with a single diesel engine in the operation. It can be concluded that the diesel electric drive shows a number of advantages for the operation of river ships that can be used for different drives of river ships

Mathematical model of energy efficiency in internal spur gears

The impact of geometric parameters of teeth and lubricating oils to the efficiency of involute internal spur gears, when the transverse contact ratio is 2 lt epsilon(alpha) lt = 3, has been analyzed in this paper. The mathematical model and computer program for determining the current and the effective value of the efficiency have been developed. The influence of the character of load distribution and energy losses due to heating effects during the meshing period is included in the factor of load distribution. The results of computer simulation are given in the form of a diagram of the current values of the efficiency during the meshing period. Also, the values of effective efficiency for the considered cylindrical gear pairs have been calculated

Mathematical model of energy efficiency in internal spur gears

The impact of geometric parameters of teeth and lubricating oils to the efficiency of involute internal spur gears, when the transverse contact ratio is 2 lt epsilon(alpha) lt = 3, has been analyzed in this paper. The mathematical model and computer program for determining the current and the effective value of the efficiency have been developed. The influence of the character of load distribution and energy losses due to heating effects during the meshing period is included in the factor of load distribution. The results of computer simulation are given in the form of a diagram of the current values of the efficiency during the meshing period. Also, the values of effective efficiency for the considered cylindrical gear pairs have been calculated

Supplementary data for the article: Stojsavljević, A.; Trifković, J.; Rasić-Milutinović, Z.; Jovanović, D.; Bogdanović, G.; Mutić, J.; Manojlović, D. Determination of Toxic and Essential Trace Elements in Serum of Healthy and Hypothyroid Respondents by ICP-MS: A Chemometric Approach for Discrimination of Hypothyroidism. Journal of Trace Elements in Medicine and Biology 2018, 48, 134–140. https://doi.org/10.1016/j.jtemb.2018.03.020

Supplementary material for: [https://doi.org/10.1016/j.jtemb.2018.03.020]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2181]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3074

Supplementary material for the article: Mesarović, J.; Trifković, J.; Tosti, T.; Fotirić Akšić, M.; Milatović, D.; Ličina, V.; Milojković-Opsenica, D. Relationship between Ripening Time and Sugar Content of Apricot (Prunus Armeniaca L.) Kernels. Acta Physiologiae Plantarum 2018, 40 (8). https://doi.org/10.1007/s11738-018-2731-7

Supplementary material for: [https://doi.org/10.1007/s11738-018-2731-7]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2193

Supplementary material for the article: Spahić, M. P.; Sakan, S.; Cvetković, Ž.; Tančić, P.; Trifković, J.; Nikić, Z.; Manojlović, D. Assessment of Contamination, Environmental Risk, and Origin of Heavy Metals in Soils Surrounding Industrial Facilities in Vojvodina, Serbia. Environmental Monitoring and Assessment 2018, 190 (4). https://doi.org/10.1007/s10661-018-6583-9

Supplementary material for: [https://doi.org/10.1007/s10661-018-6583-9]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2123

Supplementary material for the article: Spahić, M. P.; Sakan, S.; Cvetković, Ž.; Tančić, P.; Trifković, J.; Nikić, Z.; Manojlović, D. Assessment of Contamination, Environmental Risk, and Origin of Heavy Metals in Soils Surrounding Industrial Facilities in Vojvodina, Serbia. Environmental Monitoring and Assessment 2018, 190 (4). https://doi.org/10.1007/s10661-018-6583-9

Supplementary material for: [https://doi.org/10.1007/s10661-018-6583-9]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2123

Supplementary data for article: Stanojević, M.; Trifković, J.; Akšić, M. F.; Rakonjac, V.; Nikolić, D.; Šegan, S.; Milojković-Opsenica, D. Sugar Profile of Kernels as a Marker of Origin and Ripening Time of Peach (Prunus Persicae L.). Plant Foods for Human Nutrition 2015, 70 (4), 433–440. https://doi.org/10.1007/s11130-015-0515-4

Supplementary material for: [https://doi.org/10.1007/s11130-015-0515-4]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2001