Items

  • SOME ASPECTS REGARDING AN ELECTROSTATIC CLEANER PROCESS OF MARINE OILS AND DIESEL FUELS

    Tudor SAJIN; Constantin-Narcis OSTAHIE
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    This paper treats the problem of cleaning and reconditioning of waste oils and diesel fuels with mechanical impurities used in marine engines. The influence of different physical quantities involved in the electrostatic cleaner process are considered on the basis of dimensional analysis. The relative processing time is determined against the criteria, on which depends the kinetics of electrical separation in order to determine the efficiency of the process.
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  • THEORETICAL STUDY FOR EFFICIENT LENGTH AND DIAMETER APPLIED TO A COMPRESSED AIR INSTALLATION

    Ion OMOCEA
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    A compressed air installation becomes efficie4nt if the investment made leads to minimal expenses per cubic meter of compressed air. This is why we will analyze it from the economic viewpoint. All parts of the installation have a significant contribution in investment and expenses.
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  • EFFECT OF WELDING PROCESS ON MECHANICAL AND MICROSTRUCTURE PROPERTIES OF 5083 ALUMINIUM ALLOY JOINTS USED IN SHIPBUILDING

    MOHD NOOR C.W.; FERRY M.; AZLAN M.
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The present investigation is aimed to study the effect of welding processes such as TIG and MIG on mechanical and microstructure properties of 5083 aluminium alloy. The preferred welding processes of this alloy are frequently tungsten inert gas (TIG) and metal inert gas (MIG) due to their comparatively easier applicability and better economy. In this alloy, the weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often causes inferior weld mechanical properties and poor resistance to hot cracking. Two sets of 5083 aluminium alloy plates which normally used in ship construction have been selected as a sample material. The mechanical testing and microsture examination were performed and the results are compared. From this study it is found that TIG joints of 5083 aluminium alloy showed superior mechanical properties compared to TIG joints.
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  • ENTROPY GENERATION IN A STEADY STATE HEAT CONDUCTION: A STUDY FOR THE PLANE WALL

    Feiza MEMET
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    In technical applications, there are many processes developed at high temperatures. Loss of heat to the surrounding represent a loss of energy, an important task of engineers being to minimize heat losses. In all types of heat transfer processes, thermodynamic irreversibility is associated with entropy generation, which results in the destruction of available work. In a pure heat conduction process, the generation of entropy is the result of heat transfer through a finite temperature difference. This paper investigates entropy generation during onedimensional steady state conduction through a plane wall. Are considered two situations: uniform thermal conductivity without additional internal heat source and uniform thermal conductivity with additional internal heat source. For the both situation will be discussed the temperature distribution in the plane wall.
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  • FLOW FIELDS IN THE CONICAL CHANNEL OF MICRO HYDROPOWER CONVERTER IN PRESENCE AND IN ABSENCE OF TURBINE STAGES

    Tudor SAJIN; Gheorghe Marius MARIAN
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    For a new concept of micro hydropower converter with positioned in gravitational vortex flow multistage turbine rotor with different values of specific speed has been modeled the velosity field of water flow through the conical channel in the absence of the turbine stages and was determined the flow structure by the computer simulation in the presence of the turbine stages. In the first case, the stream lines appear as helical spirals. The distributions of circular, radial and axial velocity components in the boundary layer, in the potential flow (zone of the free vortex) and in the forced vortex was determined. In the second case the structure of the water flow is changes with the formation of individual swirls in every area between the blades. The water velocity increases rapidly as proximity to the drain hole and strongly depends on sink and vortex strengths.
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  • ENERGY CAPTURE IN THE GRAVITATIONAL VORTEX WATER FLOW

    Gheorghe-Marius MARIAN; Tudor SAJIN
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The theoretical and experimental study of a new type of micro hydropower converter is realized. The converter may be used for energy conversion of river water with small heads and coastal currents into mechanical work by local restructuring of water flow through a vertical conical channel in spiral form of gravitational vortex. In this vortex, at different heights of the conical channel, are positioned the rotor blades of the turbine with different values of specific speed. The characteristics of the gravitational vortex flow of water through the conical channel, the speed and the power characteristics of the micro hydropower converter were investigated and experimentally validated.
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  • THE PERCEPTIONS OF RESPONSIBLE TURKISH OFFICERS FOR INFIRMARY OF THEIR PROBLEM SOLVING ABILITIES

    Kuleyin BARIS ; Koseoglu BURAK ; Ali-Cemal TOZ
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    Comparing to all assigned jobs or work to earn a descent income, money, then no other professions that are more risky compare to seafarers. For we know that all of the jobs or works are all risky too but a seafarer is the most risky profession of all. After graduation from own school, many officers assigned for health officers on board although lack of experience. The aim of the study is to determine the perceptions of responsible Turkish officers for infirmary of their problem solving abilities’ level and to find out whether their perceptions differ according to age, gender, marital status, school graduated, competency level, experience and additional health training. In this study survey (questionnaire) method was used. Problem solving inventory (PSI) which was developed by Heppner and Petersen in 1982 and in 1993 PSI was realigned in Turkish Version by Sahin and Sahin was filled to the officers by their companies which they work as an officer. Frequency tables, descriptive statistics, reliability analysis, Kolmogorov - Smirnov Z test, single direction variance analysis (ANOVA), LSD test and independent sample t test are used in the analyses of data.
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  • SAFE ACCESS AND OPERATIONS WITHIN PORT AREA

    Vallentina GRANCHAROVA; Ivaylo GRANCHAROV
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    An important aspect of all operations performed in port area is safety. This means protection of marine environment, port structure, facilities and human’s life. The paper offers an overview of some important points, concerning safe berthing access, navigation and safety performing of cargo handling operations within the port area.
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  • MARINE PRACTICE GUIDELINES FOR FUEL CELL APPLICATIONS

    GONZALO-MUÑOZ A.; MAS-SOLER J.; NAVARRO E.; LEO TERESA J.
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    This paper focuses on the implementation of fuel cells in marine systems as a propulsion system and energy source. The objective is to provide an overview of the pertinent legislation for marine applications of fuel cells. This work includes a characterization of some guidelines for the safe application of fuel cell systems on ships. It also describes two ships that have implemented fuel cells to obtain energy, the Viking Lady, the first marine ship to include this technology, and Greentug, a reference for new tugs.
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  • TECHNO-ECONOMIC STUDY OF ELECTRIC CATAMARAN FERRYING PASSENGERS CROSSING KUALA TERENGGANU RIVER

    FERRY M.; C.W.NOOR; AMAHEKA S.
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    Catamaran floats on two demihulls, that are slimmer, shallower than single hull of an equivalent capacity, has less weight, small draught, more deck area for passengers and more stable. Due to these features catamaran may be powered by electric energy makes it more economical. Electric motors as the prime mover maintains high efficiency over a wide range of loads and speeds, has small weight, very low maintenance and repair cost compared to diesel engines or outboard motors. Battery is used as energy storage that enables the catamaran operates as ferry for transportation at rivers which is more efficiently due to its low operational cost; pollution free hence environmental friendly. The obstacle of this transportation system is that the distance to be traveled is limited and depends on the capacity of the battery. Recharging the battery should be done through an electric charger with high charging capacity per hour connected to the electricity line exist at the jetty. The monthly operational cost of catamaran boat is more less compare to the monohull diesel boat. Such type of ferry is effective for connecting two closed places on rivers or as a means of inland waterways transportation for tourism along rivers, canals or small lakes with limited sailing time. In this case the route is taken for Kuala Terengganu River at Kuala Terengganu, Malaysia.
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  • TEACHING MARITIME ENGLISH: WRITING GLOSSARIES IN EDUCATIONAL PURPOSES

    Naduya DEMYDENKO
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The paper suggests the analysis of what a glossary is and how glossaries can be used in the process of teaching/learning materials development. A glossary is considered to be a form of a dictionary. Its various formats and purposes may be of great help when planning everyday practical language or specialist teachers’ activities including assessment sessions in case if the knowledge of a term and its definition are required. The description is supported by the samples used in work with Marine Engineers.
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  • RADAR IMAGE DESCRIPTION USING AUTOREGRESIVE AR(4) TIME SERIES AND HIGH ORDER SPECTRAL MOMENTS APPROACH

    DOYNOV Bozhidar; ZACHARY Popov; CHAVDAR Alexandrov
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    This article presents an attempt for modeling and estimation of radar images of a ship (presented as a rough surface) using high order spectral moments and time series. Experiments with real images obtained by a costal surveillance radar are described. The results are estimated by using autoregressive models of fourth order. Experimental results with AR(2) and AR(4) have been compared and discussed.
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  • MODEL-BASED TORSIONAL VIBRATION OF MARINE INTERNAL COMBUSTION ENGINES - Part 2

    Nicolae BUZBUCHI; Liviu-Constantin STAN
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The purpose of the present paper is to be a tutorial one, intended to show the model of torsional vibration of the high power marine engine shafting systems. Extension of the analytic method for a multi-dimensional system, modeling of typical marine propulsion plant, and results for some realistic examples are also presented.
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  • MODEL-BASED TORSIONAL VIBRATION OF MARINE INTERNAL COMBUSTION ENGINES Part 1

    BUZBUCHI Nicolae; STAN Liviu-Constantin
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The purpose of the present paper is to be a tutorial one, intended to show the model of torsional vibration of the high power marine engine shafting systems. Extension of the analytic method for a multi-dimensional system, modeling of typical marine propulsion plant, and results for some realistic examples are also presented.
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  • PSEUDORANDOM NUMBER GENERATOR

    Denitsa BOTEVA; Tsanev YONKO; Marian TRENDAFILOV
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The paper presents a random numbers generator based on linear feedback shift register (LFSR) and hash function. The development is made under MatLAB and some statistical tests are applied to output sequences. The generator is based on dsPIC microcontroller and has an ability to modulate sine wave by FM and BPSK.
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  • A NEW TENDENCY IN EVALUATION THE SHIPS PASSAGE

    Chanev Belev BLAGOVEST
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    Many years in the maritime navigation the main problem was determination and accuracy of ships position. Solving of this problem was with great priority in the methods of evaluating the passage. All theory of navigation and passage planning was built around opportuninies for the Officer of the Watch to determine the ships position on different stages of the passage.Today, in establishing the ships passage plan, the Officer of the Watch has another criterias for evaluating the stages of the passage. Today ships position determination is not a problem at all and the accuracy of the position is very high. Today the International Safety Management Code requires another priorities in the stage of ships passage planning- which are described in the paper.
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  • INFLUENCE OF THE TECHNOLOGICAL PARAMETERS ON THE DISTRIBUTION OF THE TEMPERATURE FIELD AND THE DEPTH OF THE HARDENED LAYER DURING THE INDUCTION HEATING OF THE INTERNAL CYLINDRICAL SURFACE OF SHIP STEEL BUSHINGS

    Bohos APRAHAMIAN; Maik STREBLAU; Dimitar STAVREV; Vladimir SHTARBAKOV
    4/1/2013
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The induction heating is widely used owing to the high quality performance, versatility and precise control means of the heating process. Hardening of internal cylindrical surfaces of ferromagnetic details and achieving preset depth of the hardened layer requires the provision of certain speed of heating and cooling, determinate surface temperature and distribution in depth. The purpose of this paper is to present a concrete solution for the shape of the inductor, heating the internal surface of a cylindrical detail, such as ship bushing, and simulation of the processes occurring in the system inductor-detail to study the influence of the process parameters on the depth of the hardened layer.
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  • SIMULATION BASED TRAINING ON MARITIME EDUCATION AND APPLICATION ON ICE NAVIGATION MODULE

    Ali̇ Cemal TÖZ; Burak KÖSEOĞLU
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    From the shipping industry’s point of view cold winters mean nothing else than trouble. Navigation in Arctic waters is unique compared to all other ship operations. Significant changes in climate and their impacts are visible regionally and are expected to become more pronounced in the next decades. Trade in ice covered waters continues to grow and increasingly, operators looking for future flexibility are building ships classed for operations in ice. In the future the Northwest Passage and Northern Sea Route are likely to provide alternative shipping lines for international trade. Ice navigation is probably the most difficult and challenging mode of navigation possible. Few other areas of maritime operation are exposing the ship and its crew for more dangerous situations. The use of ship-bridge simulators is becoming an accepted method of training in the maritime education. Many simulator-based training courses were developed ad hoc, often designed to individual requirements of a shipping company or training establishment. For ice navigation module, the goal of training module is to reduce the risks of winter navigation and to ensure safe operations even in severe ice conditions. This article aims to analyze effectiveness of maritime simulation systems on strengthening the maritime training for ice navigation module in Dokuz Eylül University Maritime Faculty.
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  • THE ACADEMICIAN PROFILES OF MARITIME HIGHER EDUCATION INSTITUTIONS IN TURKEY*

    Nas SELCUK ; Celik BURCU
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    One of the most important missions of maritime educational institutions is to educate the qualified labor force meeting the international maritime manpower market needs. For that purpose in Turkey, the number of educational institutions providing manpower to the maritime industry has been rapidly increased in the last decade. Concordantly, there have been a lot of investments in laboratories, classrooms and simulators in order to enable sufficient training. Despite of all these aforesaid developments, the most important issue, instructor or academicians with maritime background, was neglected. Now, Academicians have become the most important human capital. This capital cannot be created immediately yet it can be brought into existence within a long period of time. Without this capital is not possible to train qualified seafarers, to survive in the maritime industry. The aim of this study is to determine the profiles of the maritime higher education institutions in Turkey, their capacities and profiles of the academicians with maritime background employed in such institutions. During the study, structured interview questions have been used. Data collected was obtained through official sources. Maritime higher education institutions providing education at the undergraduate level with fulltime employed academicians (with maritime background) have been evaluated via the data obtained using the methods of statistical analysis.
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  • THE STUDY OF WAVES ENERGY CAPTURE PROCESS BY MECHANICAL AND ELECTRICAL ANALOGY

    Tudor SAJIN; Dragoș-Iulian NEDELCU
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    Starting from the concept of an device for waves energy conversion, constituted by floating cylinder structure, the paper intends to carry out a comparative analysis between mechanical and electrical analogy, for a more precisely determination of parameters that have a influence on oscillating system for waves energy capture.
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  • EFFICIENCY ANALISYS OF WAVES ENERGY CONVERSION SYSTEM WITH FLOATING CYLINDERS

    Dragoș-Iulian NEDELCU; Tudor SAJIN
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    Starting from the particularities of offshore surface waves, the paper propose the analysis of a new system with floating bodies articulated, connect between them with levers, designed for potential waves energy and for its conversion. From the analysis of technical stage was chosen the cylindrical shape for which the waves energy absorption efficiency is higher than in a vertical plate case. It was established that the efficiency of capture system with floating cylinders in function by their diameters and by the ratio of lever length connection at wavelength of wave.
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  • TRENDS AND PERSPECTIVES ON THE EFFICIENCY ROMANIAN PORTS

    Cristina-Steliana MIHAILOVICI
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    This article discusses predictions on the ports efficiency in the actual Romanian ports, in the short and medium term. We are looking for answering some questions related to measures leading to development of the Romanian Ports and their management.
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  • A PERFORMANCE IMPROVING OF A TYPICAL TRANSCRITICAL CO2 REFRIGERATION CYCLE

    Feiza MEMET
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    Together with the care for our environment, the natural refrigerant CO2 is seen as an attractive solution due to its excellent advantages in refrigeration application. In some cases transcritical vapor compression cycles are used instead of the conventional vapor compression cycles (air conditioning). Transcritical CO2 refrigeration cycles present low efficiencies because of losses encountered during expansion processes. In this paper, an ejector expansion transcritical CO2 refrigeration cycle is used to improve the performance of a typical transcritical CO2 cycle since a constant pressure mixing zone ejector is used instead of the expansion device from the basic transcritical CO2 refrigeration cycle.
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  • THE CALCULATION OF THE RESISTANCE OF A FIBER REINFORCED COMPOSITE

    Ramona DUMITRACHE; Mihael CHIRCOR; Cosmin-Laurențiu DUMITRACHE
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The resistance of laminated materials can be either measured or calculated. The comparison between the two approaches points out that the second method is preferable if its results are good enough. The present essay describes an algorithm and a program designed to calculate the resistance of the unidirectional laminates.
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  • ENGLISH FOR MARINE ENGINEERS: SELECTION OF MATERIALS FOR THE LANGUAGE CLASSROOM ACTIVITIES

    Nadiya DEMYDENKO
    10/1/2012
    Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes
    The paper presents a sample of new teaching/learning materials for the language classroom activities of Marine Engineers in connection with the work on the project purposing to create the study pack for Maritime students beginning their academic career in Kyiv State Maritime Academy. The project is based on the concept of ‘early specialization’ which implies that the 1st and 2nd year students are taught both General English and Maritime English. This approach requires new teaching/learning materials (Student’s Book, Workbook, Teacher’s Book, Dictionary of Maritime Terms and others) to satisfy the needs of students in authentic communicative language resources.
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