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Conyu Grigorov Conev and Krasimir Stoianov Davidov

References [1] Brosh J. T., Mechanical Vibration and Shock Measurements , Bruel & Kjar, 1980, 63. [2] Кирилов В. М., Основи за устройството и проектирането на стрелковото оръжие , София, ДВИ, 1975, 303. [3] Пановко Я.Г., Основы прикладной теории колебаний и удара, Ленинград, масиностроене, 1976, 120. [4] Монтгомери Д.К., Планирование експеримента и анализ данных , Ленинград, Судостроене, 1980, 30.

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Alin-Constantin Sava, Ioan-Liviu Piticari, Diana-Georgeta Nistoran and Cristian-Emil Moldoveanu

References [1] *** Rheinmetall Handbook on Weaponry , Dusseldorf, 1982 [2] Roşca Aurel, Automatic weapons – The resultant vibration of the barrel. The influence on the firing precision , Military Technical Academy Press House, Bucharest, 2002 [3] Piersol Allan and Paez Thomas, Harris’ Shock and vibration Handbook , 6 th edition, McGraw Hill Handbooks, 2009

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Cornel Haţiegan, Gilbert Rainer Gillich, Gheorghe Popovici and Luminita Haţiegan

References [1] Cornel Haţiegan, Edwald-Viktor Gillich, Ovidiu Vasile, Marian-Dumitru Nedeloni, Ioan Pădureanu, Finite Element Analysis of thin plates clamped on the rim of different geometric forms. Part I: Simulating the Vibration Mode Shapes and Natural Frequencies, Romanian Journal of Acoustics & Vibration, Vol.XII, No.1, 2015. [2] Cornel Haţiegan, Edwald-Viktor Gillich, Ovidiu Vasile, Marian-Dumitru Nedeloni, Marcel Jurcu, Petru Magheţi, Finite Element Analysis of thin plates clamped on the rim of different geometric forms

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Svilen Spirdonov and Svilen Stefanov

Abstract

The following report shows methods for determination of the coefficients of stiffness and damping, for softening the vibrations, which ensue in an armoured vehicle’s suspension from the shooting of a mounted machine-gun. The methods are based on a model of the movement smoothness, in which is additionally included the signal of the machine gun’s recoil.

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Galina Ivanova

References [1]. Bulgarian Standard БДС EN 60068-2-6:2007. Environmental Testing. Part 2-6: Tests. Test Fc: Vibration (Sinusoidal). [2]. Petkov, B. M. Artillery Fuzes. Theory, Estimate and Structures. Saint George MoD Publishing House, Sofia, 1994.

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Cornel Haţiegan, Mihaela Molnar, Sorin Trocaru, Ioan Pădureanu, Marcel Romulus Jurcu, Lidia Filip Nedeloni and Florin Ilie

Abstract

This paper presents thermal analysis with finite elements for a plate of steel covered on the surface with a thin layer of Teflon. There is the possibility of identification of that part responsible for beginning of the thermal degradation using the vibrational model. The thermal analysis with finite elements made with ANSYS program enables monitoring and determination of plate variation of temperature. This variation of temperature could cause significant changes in guided wave propagation.

Open access

Ioan Virca

Abstract

The use and maintenance of technical systems throughout their lifecycle aims at achieving goals that allow for high values of productivity and availability characteristics of these systems. In the economic policy of each state or private organization or state institution, there is the right to determine the type of adequate maintenance system within the maintenance strategy adopted. Thus, the types of maintenance systems recognized in the technical domain are analyzed from the point of view of the two previously-mentioned features, productivity and availability, thus making the predictive maintenance system, derived from the preventively-planned one, advantageous for all organizations. It is obvious that the current trend is to spread this predictive maintenance system, according to which the interventions will be carried out before the malfunction occurs, depending on the periodically measured values of global pressure, flow, energy consumption, temperature, current, voltage, vibrations, etc.

Open access

Vasile Nastaiescu and Vlad-Andrei Barsan

References [1] Hallquist, O. John, LS-DYNA Theory Manual, Livermore, California 94551, 2006, [2] Liu, L., Chua, L.P., Ghista, D.N., Element-free Galerkin Method for Static and Dynamic Analysis of Spatial Shell Structures, Journal of Sound and Vibration 295 (2006) 388-406, www.elsevier.com/locate/jsvi [3] Liu, G.R., Gu, Y.T., An Introduction to Meshfree Methods and Their Programming, Published by Springer, P.O. Box 17, 3300 AA Dordrecht, The Netherlands, 2005 [4] Năstăsescu, V., Ştefan, A., Lupoiu

Open access

Adrian Popa, Ionuţ-Cristian Scurtu, Beazit Ali and Marian Ristea

References [1] Scurtu I.C., Manufacturing and design of the offshore structure Froude scale model related to basin restrictions , Paper ID: A-30, Modtech Conference 2015, The Third International Conference on Modern Manufacturing Technologies in Industrial Engineering, Mamaia, Romania, June 17-20, 2015. [2] Scurtu I.-C., Pricop M., Babiuc B., Study of offshore structure design related to Ansys stress, displacement and vibration modes, Constanţa Maritime University Annals, Year XIV, Vol.22, ISSN 1582-3601, Constanţa, 2014. [3] STAN L

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Gheorghe Samoilescu, Dumitru Iorgulescu, Robert Mitrea and Laura D. Cizer

Abstract

This paper presents aspects of the steering gear onboard a merchant ship by analyzing aft and bow systems based on automation and use of modern propulsion. The choice of the transverse propeller is based on several economic considerations (its price, consumption, efficiency, etc.), technical considerations (positioning, size, vibrations induced in the ship’s hull), and maneuverability considerations (the ship’s turning rate under the action of the propeller. Accordingly, the propulsion system can come in various sizes, power values, shapes of the tunnel, and can present fixed or variable pitch propellers. Depending on the maneuverability of the ship, the transverse propulsion is analyzed by taking into account two tests: the turning of the transverse propulsion system test in calm and windy weather, and the steering test. The automation system is designed to control and monitor the on-board operational systems and equipment, and it encompasses a wide range of control, monitor and alarm. The integrated navigational equipment includes the following sub-systems: navigation consoles, ship handling consoles, dynamic positioning consoles, anchoring and deck operations consoles, and propulsion system control consoles. The propulsion control system is especially dedicated to the propeller and thruster control system, resulting in a joint control system, and the cables are reduced in number since the communication lines are used in series. The mandatory condition for successfully solving the problem with the complex automation of naval installations and equipment is the construction of complex automatic control systems (ACS), consisting of: automated commands or remote controls, a system of collecting, processing and displaying information, as well as a system of control, fault detection and diagnosis