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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

Open access

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

Abstract

This paper presents variants of propulsion systems as the main factor in the analysis and design of the power system of a sea-going or river vessel; this topic is also under research study within two doctoral theses. The analysis of the ship - main propulsion- thruster assembly is made according to the requirements imposed by the market economy. The parameters to be considered when choosing a propulsion system are: the cost of the investment, the specific cost of transport that depends both on the specific fuel consumption and on the number and level of pay of the crew members operating the propulsion system, the propulsion efficiency, the high safety in handling, and the control accessibility during operation. The Pod and Azipod propulsion systems are analyzed in terms of advantages and disadvantages compared to conventional propulsion systems. The azimuth thrusters can ensure maximum push in any direction regardless the speed of the ship, and thus can change the course of the ship according to its handling needs. The azimuth thrusters do not only operate in horizontal but also in oblique angles, providing the ship with great maneuverability, even at low speeds, where classical rudder systems have poor performance

Open access

Adina Mitrea, Maria Mota, Daniela Patru, Amorin Remus Popa, Diana Protasiewicz, Robert Dinu, Cristina Muntean, Raluca Dina, Magda Sandu, Flavia Dinu and Betty Bornagel

Abstract

As the latest data from the International Diabetes Federation (IDF) have shown, diabetes mellitus (DM) prevalence and incidence are continually increasing. Our purposes were to identify the socio-demographical characteristics of the subjects diagnosed with DM prior to this study, to establish the percent they represent of the studied group, to evaluate the metabolic control of the subjects enrolled in the study, as well as to ascertain whether the blood glucose level or the glycated haemoglobin (HbA1c) measurement leads to the detection of a higher percentage of DM newly diagnosed cases. The study conducted in 3 Romanian cities enrolled 4133 subjects (1340 from Craiova, 1224 from Oradea and 1569 from Sibiu). 1413 subjects (34%) reported having been diagnosed with DM prior to our study. Most of the subjects previously diagnosed with DM, 65%, take oral antidiabetic agents (OAA), 13% take insulin and 4% take both OAA and insulin. 20% of the subjects who did not report DM had a blood glucose level ≥126mg/dL and 17% of them had an HbA1c ≥6.5%, leading to a high number of newly diagnosed DM cases, therefore emphasising the importance of the simultaneous determination of these two parameters. The results of this study confirm the increasing prevalence of DM and the necessity of future studies in order to asses DM accurate prevalence in Romania.