Items · Journal of Marine Technology and Environment

DEFINING THE SHIP MAGNETIC PERFORMANCE BY MEANS OF PASSAGE CHARACTERISTICS

SAMOILESCU Gheorghe; MARIN Georgiana; SERGHEI Radu

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Defining the necessary level of protection for the ship in order to fulfil its operational purpose is a prerequisite in ship magnetic signature analysis and in adopting the appropriate method of reduction. In the study of ship magnetic field it is vital to thoroughly establish its components for an accurate assessment by using several efficiency indicators chosen precisely on the basis of those components. This paper performs the analysis of the passage characteristic of a medium sized special ship on the basis of its longitudinal magnetic characteristic. Furthermore, the results acquired through Fourier harmonic expansion are compared to the measured values. The time differential of the passage characteristic is also significant in this way. Therefore the possibility of passage characteristic control and implicitly the ship protection against magnetic mines emerges by means of complete knowledge of the ship’s magnetic field and adjusting the speed when transiting a mine danger area.

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COLLABORATIVE LEARNING FOR COMPETENCE DEVELOPMENT

PRASAD Rajendra; BALDAUF Michael; NAKAZAWA Takeshi

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Notwithstanding the remarkable progress made in the reduction of accidents involving ships, its personnel, shore facilities and the marine environment the accidents of disastrous consequences still occur with loss of valuable life and damage to property. One of the accident causation factors, as identified by safety investigations of accidents and aetiological research, points to the deficiency in the competence of shipboard personnel. Although minimum standards of seafarers’ competence have been specified and internationally agreed through the implementation of International Convention on Standards of Training, Certification and Watch-keeping of Seafarers (STCW), there still exists a wide diversity in the global maritime education and training (MET) standards. While the convention gives some guidelines on the standards of necessary competence and its assessment, it is silent on the actual contents and the method of delivery of curricula. Prevailing methods of MET and its assessment engender conditions that do not promote appreciation of deep learning and comprehension of taught material. This paper looks at various features of collaborative learning methods with a view to examine feasibility of its application to MET and possible advantages driven from its application to enhance competence of seafarers.

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AN ASPECT OF MAINTAINING R-22 SYSTEMS IN REFRIGERATED TRANSPORTATION. THE SELECTION OF R404A

MEMET Feiza

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Refrigerated transport is essential for our society due to the need to preserve and protect food, drugs or medical supplies during transportation, to the benefit of the people worldwide. Since many HCFCs are powerful greenhouse gases, the replacement of these refrigerants in refrigerated transportation asks efforts done to select the correct refrigerant for this application. In this respect, this paper deals with challenges and solution for this issue. The classical criteria to be considered when choosing a refrigerant are: thermophysical properties, technological, economic, safety and environmental aspects. It is seen as a solution for the replacement of HCFC22 (R22), the refrigerant belonging to the HFC family, R404A. R404A is a chlorine free chemical. It permits the maintenance of the existing R22 equipment, this being an economic advantage, especially in time of crisis. It is made a thermo – energetical comparison between R22 and R404A, resulting that R404 is suitable for refrigerated transport.

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ANALYSIS OF BLACK SEA POLLUTION – RISKS, CONSEQUENCES AND MEASURES

MIHAILOVICI Cristina-Steliana

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Many tanker accidents produced in the Black sea caused oil pollution, while coastal industries continue to discharge waste products directly, with little or no treatment. This in correlation with huge industrial activity in the area, shipping and offshore oil exploration created critical environmental state, and all aesthetic beauty has disappeared from this area, making place for the ugly site of tremendous pollution. Black Sea pollution has increased in recent years because of heavy rains, which led to the transportation of large quantities of silt, and because of the overflow in the Danube of chemicals (pesticides and fertilizers) used in Germany and Austria. Meanwhile, the abandoned vessels along the Danube and Black Sea coast are a permanent source of pollution with heavy metals. This paper aims to show the role of the EMSA Agency which is able to provide pollution response and operational and technical assistance, but especially the responsibility of all who work in the maritime field: companies, people, associations and governments.

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CONSIDERATIONS ABOUT THE 'GREEN SHIP' CONCEPT - A SOLUTION TO MINIMIZE MARINE POLLUTION

GROSAN Nicolae

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

About 90% of goods exchanges are performed on maritime way. There is involved a large number of ships such as cargo, tankers, containers, bulkcarriers, passengers’ vessel, which must satisfy the commercial needs. All of these requirement, depends in a great measure of the oil consumption. The Green Ship term refers to the ideal ship regarding the marine pollution control. There are two aspects with common applications regarding Green Ship term: - The first aspect is looking for: the applied measures which are considered for the quality of the fuel, replacement of the classic fuel with high sulphur content, designed values of the naval engines where the burn process is completed, the other kind of fuels for engine propulsion, ballast treatment or zero ballast, recycling of the sewages and for new ship’s hull paints without any TBT. - The second aspect of Green Ship term is looking for the vessel propelled by other methods than classic, named non-conventional procedures or unconventional methods, where the main engine is replaced by electrical motors, solar cells, sails elevated at certain altitude (kite), fixed and mobile sails with solar cells incorporated. Is the Green Ship the ideal concept and ideal ship which can reduce the marine pollution at minimal level in the nearest future?

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THE INFLUENCE OF FACTORS ACTING ON THE FRICTION POWER LOSSES IN MECHANICAL SEALS WITH SLIDING RINGS

GRIGORESCU Lucian

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In terms of users of such mechanical packing, the value of lost friction power and the factors contributing to the increase or decrease of this power is of maximum interest.

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THE USE OF MAGNETIC FLUIDS TO OBTAIN AND BUILD SEALS

GRIGORESCU Lucian

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Magnetic fluids, sometimes called “ferro-fluids” are a new category of synthetic materials combining fluid properties with magnetic properties of solids. They are colloidal suspension of ferromagnetic particles into a basic liquid. Magnetic ultrafine particles (30-160A0) are integrated in a basic liquid by means of surface-active substances, which create an elastic coating (layer) around each particle and, with thermal agitation, ensure the stability of suspension even in the highly non-uniform magnetic fields

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TOTAL CELL COUNT, SINGLE CELL BIOMASS AND GROWTH RATE IN MARINE MICROCOSMS SUPPLEMENTED WITH GASOLINE AND GASOLINE-ENRICHED MARINE POPULATIONS

GHITA Simona; ARDELEAN Ioan

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In this paper we present the results concerning some microbial parameters (total cell count, biomass and percentage growth rate) in marine microcosms supplemented with gasoline and gasoline-enriched marine populations. At the beginning of experiment, total cell population density was higher in microcosm supplemented with gasoline-enriched marine population and carbon / nitrogen source (gasoline (1% v/w) and ammonium nitrate (0.005% w/w)) as compared with the other microcosms, then a significant decrease in total cell population density was observed, due probably to gasoline consumption and/or to the significant bacteriolithic activity (litic bacteriophages and/or predatory bacteria). Our results argue that gasoline can sustain the growth of endogenous micorbiota as well as of previously gasolineenriched marine populations, thus sustaining the further research on the use of gasolineenriched marine populations for bioremediation of polluted sites (bioaugmentation)

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DAMAGE STABILITY CRITERIA IN AIRCRAFT CARRIERS

FERNÁNDEZ Rodrigo Pérez; JOSÉ MARÍA Riola Rodríguez

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The International Maritime Organization (IMO) agreements are not always appropriate for the majority of aircraft carriers, so that the military mission demand solutions in the design and operation that are not fully compatible with the philosophy of the conventions “IMO” and prescriptive solutions. Separate rules of the Classification Societies of the conventions “IMO”, to apply to warships create a vacuum that can lead to confusion. This confusion can be misinterpreted and as a result there can be a drop in safety standards. Stability in case of collision is a critical theme to maintain buoyancy in ships. These aspects are even more critical given the increasing size of the boats and the growing number of passengers and crews onboard. Both experience and performed studies demonstrate that the most dangerous issue for the ships with closed deck is the impact of an accumulation of water on the deck. The studies have clearly shown that the residual freeboard of the ship and the height of the waves in a specific sea area influence in a very relevant manner the amount of water that could be accumulated after a clash. The article concludes by presenting a series of comparisons between the criteria used by both, leading to some interesting conclusions as to the current criteria used by the navy. This can be enormously improved with a few minor changes, to maintain the integrity of its basic approach, and increase the similarities with the criterion of “IMO”, such as the calculation of water on deck out in the Stockholm Agreement.

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MILITARY PROMOTIONS OF NAUTICAL TEACHERS BY THE END OF THE 18TH CENTURY: REWARD FOR MERITS OR A MEANS TO CONTROL NAUTICAL SCHOOLS?

DELGADO Juan Jose Rios; DELGADO Enrique Rios; SAAVEDRA Maria Jose Espinoza

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

By the end of the 18th century the Spanish nautical school teachers were military promoted as a means to reward their devotion to teaching and their input as cosmographers. These well-deserved promotions were also a way to acknowledge their taking part in several military conflicts during which teachers had defended the Spanish Crown. However, the following paper will discuss the fact that some of these promotions were used by the Escuelas Particulares (Private Schools) and the Real Junta Particular de Comercio (Royal Particular Joint Trade Board) of Barcelona as a tool which allowed teachers to become members of the Spanish Royal Navy.

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SUSTAINABLE DEVELOPMENT PROGRAM AT THE FACULTY OF NAUTICAL STUDIES OF BARCELONA. NAUTICAL ENGINEERING EDUCATION

CASTELLS M.; MARTÍN A.; ORDAS S.; AGUILAR S.; SOLÉ M.

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Nautical engineering education institutions play an important role and are a key tool in the future sustainable maritime transport and naval world. This paper addresses the role of nautical engineering education in the learning and implementation of the competence of sustainability and social commitment (SSC) in the Nautical Faculty of Barcelona and presents results of the first year of the implementation of the environmental program STEP2015 at the Universitat Politècnica de Catalunya.

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INFLUENCE OF POWER SOURCE PARAMETERS IN INDUCTION HEATING OF BEARING BUSHINGS OF SHIP PROPELLER SHAFTS

APRAHAMIAN Bohos; STREBLAU Maik; MARINOVA Maria

4/1/2011

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Alongside the existing classical methods of volume heating of the bearing bushings for installation on propeller shafts the possibility of heat treatment using low-frequency induction heating is very newsy and hopeful. A major disadvantage of most methods of heating is the large energy consumption and the emergence of unacceptable temperature differences in the detail, leading to the appearance of various defects in its structure. This requires a detailed examination of the processes using the method of induction heating.

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KINETIC ACTIVITY OF SOME TRANSITION METALS COORDINATION COMPLEXES IN SEA WATER

ZAGAN Sabina

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Sea water has an important role not only in coordination process due to the presence of micro-organisms exist in marine plankton, but also in the decomposition process at a moderate value of pH. All the coordination reactions products remain in the sea water surface and their decrease or increase of concentration could be correlated and predicted by determining the kinetic activity. The kinetic rate has been determined in sea water using a pH of 7,5 and 8,5 at 20 and 25oC temperature and 1 atmosphere pressure for Ni (II) and Au (III) coordination complexes.

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APPLIED RESEARCH REGARDING THE PROJECTION OF A SUBMERSIBLE ELECTRIC GENERATOR

SAMOILESCU Gheorghe; NICOLAE Sergiu; MARIN Dorian; SAMOILESCU Adelina; KAITER Edith

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The paper presents a new model of a perfect watertight submersible electric generator, tightness which is due to a pair of simerings directly connected to the generator’s shaft, in which the impulse is carried out by means of permanent magnets from rare grounds mounted on the electrical machine’s rotor with the help of epoxy resins. Due to the total tightness of the generator, the rolling bearings (ball bearings) were used, increasing in this way the mechanical yields on shaft. The encased joint stator winding is not movable and it can be both single and three phased. The inductive field (rotor) is made up of permanent magnets and the induced (stator) is equipped with single phased winding situated on the surface of cylindrical yoke laminations. The subsystems rotor and stator are independently sealed; water can flow into the space between the fittings and in the camps.

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SPECIAL SYNCHRONOUS MICRO GENERATORS USED IN HYDROELECTRIC ENERGY CONVERSIONS

SAMOILESCU Gheorghe; SERGIU Nicolae; DORIAN Marin; SERGHEI Radu; CIZER Laura

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In order to meet the energetic needs in isolated areas by means of wind or hydro technical potential, conversion micro units can be used. This paper reveals the extensive investigation into the use of synchronous AC micro generators operating on water energy, performed by INCDIE ICPE-CA, “Mircea cel Batran” Naval Academy and U.P.B. Our research includes: normal model of a generator, reversed model in accordance with its functional purpose: out of water (in atmosphere) or in immersion.

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MODELLING PRESSURE WAVES IN FUEL INJECTION PIPES

SABAU Adrian; BARHALESCU Mihaela

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Fuel injection pipes pressure are measured and computed to study the injection system characteristics at partial load in a direct injection Diesel engine whit a distributor-type injection pump. The fuel injection simulation is based on a linear model. The governing equations are solved by the finite difference method.

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LEISURE TIME AND ITS IMPORTANCE TO MARITIME SAFETY

RODRÍGUEZ-MARTOS Ricardo

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Often when we speak about safety on board ships we consider technical aspects and if we take in account human factor then we think about stress, working hours, drougs, etc. Leisure will be not seriously consider as something related with safety. This paper tries to introduce the concern about the importance of leisure time for a proper psychological condition of a seafarer for his own safety and the safety of the ship.

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A WAY FOR INVESTIGATION OF ELECTROMAGNETIC TRANSITIONAL DYNAMIC PROCESSES IN SHIP ELECTRICAL POWER SYSTEM

PETKOV Petko; NEDEV Marin

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

There is an untraditional way, connected with analysis and estimation of electromagnetic transitional dynamic processes in ship electrical power system. The way is based on image space vector theory and gives an opportunity to solve complicated electromagnetic problems and problems, connected with education. Including of such way in investigation the problems in “Ship Electrical Power Supply” is much more clear and easier. The analysis and estimating of complicated transitional and dynamic processes in ship electrical power systems becomes easier and clear, especially with tendency of widely speeded and used power electronics units in ship electrical equipment.

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EXERGETIC STUDY OF NAVAL TECHNICAL WATER GENERATOR

OMOCEA Ion

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

This paper presents the usual methods of sea water distillation at under-atmospheric pressure using the heat from the main engine cooling water system. In the first case, preheated condensation sea water is introduced in the technical water generator. In the second case, the sea water supply is not pre-heated.

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COMPARATIVE ANALYSIS BETWEEN HYDROELECTRIC DEVELOPMENTS AND TIDAL STREAM DEVELOPMENTS

NUÑEZ-RIVAS LUIS R.; AMABLE LOPEZ-PIÑEIRO; LEO TERESA J.; MORAN JOSE L.

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The Hydroelectric Developments (HD) technology is very well known due to the fact that it has been studied during the last 120 years. To generate electricity from the water in the rivers or dams, different technologies have been developed but at the end only four of them are used: Pelton, Francis, Kaplan and Bulb turbines. Those technologies have had a large development although, at present, scientists and engineers are working hard to increase their efficiency above 95% in some cases. On the other hand, the Tidal Stream Developments (TSD) technology is at the beginning of its life and the existing developments are mainly used as a test to improve the technology than to generate and sell electricity. Nowadays a number of different technologies are being studied because practically each manufacturer has developed its own solution. The objective of this paper is to show analogies and differences between Hydroelectric Developments and Tidal Stream Developments as technologies suitable to generate electric power from the marine currents energy.

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THE EXPLOITATION OF MARINE CURRENT´S ENERGY ON THE STRAIT OF GIBRALTAR

NUÑEZ - RIVAS LUIS R.; ROJAS EVA M. NOVOA

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The two great currents of water going along The Strait of Gibraltar give rise to an interchange of large masses of water between the Mediterranean Sea and the Atlantic Ocean. They flow one over the other in opposite directions and both are very important renewable sources of energy that at present time are not in use at all. This work begins with a description of the way in which the energetic potential of both currents can be estimated, afterwards a study on the possibilities of getting a partial use of this potential is done, without navigation´s restrictions and also looking for the protection of the marine environment. Indeed, the work shows how to use the energy source with several types of submerged turbines that are being developed nowadays, the analysis about where the devices must be placed is done and which are the rates of electrical energy that will be get. Finally, the paper is concluded giving an exposition of the basic parameters for the design procedure of one submerged electrical generation park located in the zone. How the devices must be arranged into the current is indicated and the forecast of the energy production of the park is done

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RECOVERY OF LOW-TEMPERATURE WASTE HEAT AND LNG COLD ENERGY

NOVAC Iordan; OLTEANU Vasile

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

This paper has proposed a combined power system, in which low-temperature waste heat can be efficiently recovered and cold energy of liquefied natural gas (LNG) can be fully utilized as well. The generation of electric power using the Organic Rankine Cycle appears the most practical. It is found that less energy in the low-temperature waste heat can be converted to the power by organic Rankine cycle because boiling essentially take place at constant pressure and temperature in the evaporator.

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BACKGROUND SUBTRACTION METHODS FOR MOTION DETECTION IN VIDEO SURVEILLANCE SYSTEMS

NIKOLOV Boris; KOSTOV Nikolay; VELIKOV Nikolay

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

A main activity of many computer vision systems is foreground object detection. Motion is used in a video sequences to identify target objects. Many background subtraction methods have been proposed to identify motion that belongs to a moving object. Each has advantages and disadvantages when it is applied in different conditions. An overview of five background subtraction methods is proposed in this paper. The selected methods described and compared are: temporal averaging, frame differencing, Kernel Density Estimate, Σ−∆, and mixture of Gaussians. One of the features that was found, was that the more complex methods, such as Kernel Density Estimate and mixture of Gaussians achieve high precision and recall when applied to practice. A lower precision and recall were the results of the more basic methods. However the more basic methods are cheaper in computational cost

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ADVANCED ANALYSIS TOOLS OF ENERGY CONVERSION SYSTEMS

MEMET Feiza; STAN Liviu

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In accordance with increased global demand for a clean and efficient sea transport, the marine energy sector became lately very sensitive to this subject. Energy conversion systems on board the ships should produce energy – intensive products at sea. In order to analyse and after that to improve such systems, are presented important tools at the hand of marine energy specialists: exergoeconomic analysis and exergoenvironmental analysis. By using the both methods is possible to reduce costs in energy conversion systems and to assess environmental impacts, in order to optimise energy conversion systems from economic and ecological point of view.

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FUEL CELLS TECHNOLOGY IN MARINE AND NAVAL MEDIA

LEO TERESA J.; GONZALEZ Oscar; GOMEZ-BEY Ana; CADARSO Luis; NAVARRO Emilio

10/1/2010

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In this work, the possibility of implementing fuel cell technology in marine and naval media is considered. The potential application fields are revised and the main projects in each area that, at present, are being developed are discussed. Some already operative commercial applications such as submarines and small scale power generation are described. The main constraints from the environmental and technical points of view are analysed in order to elucidate the viability of future developments.

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