Items · Journal of Marine Technology and Environment

TWO ZONES THERMODYNAMIC MODEL FOR HIGH SPEED MARINE DIESEL ENGINES

Dawwa MAHRAN; Paul BOCANETE

4/1/2015

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

In this paper two-zone thermodynamic model has been used for modeling the combustion process in direct injection diesel engine based on the results of modeling the combustion process by using single zone thermodynamic method. Single zone thermodynamic method depends on the average value of in-cylinder temperature and pressure, which considered one of the main defects of using one-zone thermodynamic model. Hence, developing a new model is very necessary especially for better description of the in-cylinder peak temperature during the combustion process. The concept of two-zones thermodynamic model is based on dividing in-cylinder gases in two zones the first zone is unburned zone which contains fresh air and the injected fuel, and the second zone is burned zone which is formed from combustion products with high temperature. The importance of the two-zone thermodynamic model is using it to calculate and to model Nox emissions. The formation of Nox emissions highly depends on the in-cylinder peak temperature. Hence, the more accurate results in modeling the temperature of in-cylinder gases lead to obtain more accurate results in modeling Nox emissions

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MODELLING THE HEAT TRANSFER PROCESS DURING THE COMBUSTION IN MARINE HIGH SPEED DIESEL ENGINES

Dawwa MAHRAN; Paul BOCANETE

4/1/2015

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

The heat transfer in marine diesel engines is a complex phenomenon that occurs by two main components, the connective and radiative components under varying conditions such as temperature, pressure, and composition of incylinder gases. Hence, modeling the heat transfer phenomenon during the combustion process in high speed marine diesel engine imposes many difficulties in determining the heat flux through the combustion chamber walls. Many researches have been carried out many studies to understand and to model this phenomenon. Since modeling this phenomenon is an important step for modeling the whole combustion process which takes place inside the combustion chamber, many models and correlations of these models have developed for modeling this it in satisfied results and in a relative short time. This work concentrates on the two main methods for modeling the heat transfer in diesel engines which they are Hohenberg, Woschni and their correlations, with the use of MATLAB program for numerical modeling.

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APPLICATION OF SOME NEW POWER QUALITY INDICES IN ANALYSIS OF THE SHIPBOARD ELECTRICAL SYSTEM EFFICIENCY

Ginka IVANOVA; Valentin GYUROV; Rumen KIROV; Bohos APRAHAMIAN

4/1/2015

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

Improving the quality of electricity and electromagnetic compatibility is a topical issue in shipboard electrical power systems as these concern two main technical aspects. First is to improve the electromagnetic compatibility, which leads to improvement of the operating modes of the equipment and thus increase of the overall reliability of the system. Second aspect is related to the quality of electricity leading both to increase in overall reliability and refinement of measures to reduce the power and energy losses. The latter is particularly relevant, since it is directly related to saving primary energy sources - liquid fuels, and this in turn leads to reduction of greenhouse gas emissions. This paper focuses on the possibilities of using some new quality indicators of electricity and electromagnetic compatibility, which are not regulated by normative documents. Practical software application has been developed in MathCAD Prime 3.0 environment and its use is shown in experimental studies of cruise ship class 1A1.

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COMPARATIVE APPROXIMATE STUDIES ON THE SHIP’S ROLLING MOTION

Dumitru DELEANU

4/1/2015

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

The new geometrical and analytical techniques of nonlinear dynamics offer to the naval engineer ideal tools for studying the ship dynamics and stability. Between them, the bifurcation diagram, the Poincare map, the phase plane, and the time histories are considered in the paper in an attempt to demonstrate the low period solutions of the asymmetric roll equation derived by Kan and Taguchi. The model assume a linear damping, a restoring moment represented by a third-order polynomial and a single frequency harmonic excitation. For moderate forcing amplitudes, the system exhibits a period 1 motion, characterized by a period doubling bifurcation to a period 2 motion that warns about the beginning of a period doubling cascade to chaos. Two different approaches, the Fast Fourier Transform and the Harmonic Balance Technique are used to obtain approximate solutions for the period 1 and 2 motions and to predict the period doubling bifurcation by a stability analysis. The two sets of solutions match reasonably well with the numerical solution, especially for the first mentioned approach.

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THE SATELLITE NAVIGATION SYSTEMS – STATUS, PROBLEMS, FUTURE

Yuriy DACHEV

4/1/2015

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

The satellite navigation systems are very important for the contemporary navigation, including and maritime navigation. Currently, there are several satellite navigation systems, used actively for navigation. There are several systems, which are currently being constructed. To provide the necessary coordinates and other navigation dates, they use geodetic reference systems (GRS). GRS are systems of parameters, describing the Earth as a complex geometric and physical figure. These parameters are defined based on the large amount of geodetic, astronomical, gravimetric, Doppler, geomagnetic and others measurements, related to the determination of the figure of the Earth. In world practice, including and satellite navigation systems, are used parameters of several GRS systems - of US, Russia, China, India and others. Can be mentioned that during 1979 was developed by the International Association of Geodesy and Geophysics (IUGG) international GRS system, which is recommended for application in various geodetic activities. This system is known as GRS 1980. There are some differences in the values of some of the corresponding parameters of the various GRS due to different Earth measurement databases, which are used for their determination. These parameters are continuously specified during the performing of every subsequent Earth measurement and adjusted so that GRS systems to be modified without changing of their abbreviations. There is an irreversible trend regarding getting near of values on corresponding parameters in the different GRS to the internationally accepted, moreover these differences are negligible.

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GIS TECHNOLOGY IN MARITIME: A MET INNOVATION AT MAAP

Dr. Angelica M. BAYLON; VAdm Eduardo Ma R. SANTOS

4/1/2015

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

This paper introduces MAAP, its curriculum and research and extension initiatives including but not limited to one of MAAP latest best practices in introducing GIS to its community (internal and external) who share similar passion for MET innovation. The various GIS–based accomplishments led and shared by MAAP as part of its Research and Extension Services (RES) initiatives are presented namely: several GIS-based papers presented and published both local and international; GIS-based project proposals for campus management enhancement prepared for MAAP, Bataan Peninsula State University (BPSU), Lyceum University of the Philippines ( LPU) and Catanduanes State University (CSU); capability Training on GIS for MAAP community and other interested institutions; and Commission on Higher Education (CHED) and Department of Science and Technology (DOST)- endorsed National 3-day GIS Conference are also discussed. There are 78 proposed GIS-based research project workshop outputs currently being implemented by 20 higher educational institutions (HEIs) in the Philippines, 17 of which are applicable to any maritime education and training institutions (METIs). MAAP has six on–going GIS- based special academic research and development projects which this paper intends to share to co-AMFUF members.

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STUDY OF A FREQUENCY CONVERTER POWERED BY SINGLE PHASE VOLTAGE DESIGNED TO CONTROL THREE-PHASE INDUCTION MOTOR

Bohos APRAHAMIAN

4/1/2015

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

The paper presents the design and the experimental study of a prototype of frequency converter powered by single phase voltage designed to control three-phase induction motor for the needs of the Laboratory of electric drives of the Technical University - Varna. A number of tasks related to the design of the basic elements of the frequency converter as a bridge rectifier, bridge inverter and driver board are determinate and solved. A special programming of the converter is realized concerning different operating regimes of the three-phase induction motor. In addition, numerous experiments are conducted with the real-made prototype.

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EDUCATION REGARDING GREEN REFRIGERANTS IN C.M.U.

Daniela-Elena MITU

10/1/2014

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

From technical point of view and from environmental point of view, and also for a sustainable development of our society are needed tools which enable to analyse the effects of human activities, including maritime transport. Refrigerated transport is essential for our society due to the need to preserve and protect food or medical supplies during transportation, to the benefit of the people worldwide. But the education of future marine engineers is in closely connected to environmental protection. The paper is focused on needed to knowledge and to understanding the working principles of the marine refrigerating plans, tools which should be at hand of future marine engineers. These competences should be gained during faculty, through a discipline called “Marine Refrigerationg Plants” included in the curricula of the license program entitled “Electromechanics”, developed in C.M.U. This paper is mainly focused on the selection of refrigerants. There are some classic selection criteria: thermophysical properties, technological and economic aspects, safety and environmental factors; however, in addition to these criteria, others have to be considered: local regulations and standards and “cultural” criteria.

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THEORETICAL APPROACH FOR OPTIMAL DESIGN OF SHELL AND TUBE HEAT EXCHANGERS ON GENETIC ALGORITHM BASIS

Feiza MEMET

10/1/2014

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

Heat exchangers are devices used to transfer heat between at least two fluids heaving different temperatures; in most of the situations, these fluids are separated by a solid wall. Shell and tube heat exchangers are the most common type of heat exchangers; this is why more attention on their design, optimization and analysis is absolutely needed for energy conservation in the process of heat transfer. This paper presents an approach related to optimum design of shell and tube heat exchangers. The approach relies on the genetic algorithm for optimization of this kind of devices. The genetic optimization algorithm is based on the value of an objective function. It will be assumed that the objective function is the total cost function, which should be minimized. The use of such a method in practice will leed not only to optimal geometric design features, but also to the consideration of economic aspect of these devices.

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SIMILARITY CRITERIA FOR SHIP MODELLING AND MAGNETIC SIGNATURE ANALYSIS

Georgiana MARIN; Gheorghe SAMOILESCU; Octavian Baltag

10/1/2014

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

In order to analyze the magnetic signature of a naval ship, there was employed a physical scale model of the respective vessel. The model was built to a scale of 1:100, respecting the geometric similarity criteria, in terms of main dimensions proportionality. A physical similarity criterion characteristic to the magnetic signature issue was formulated, taking into account the ratio between the hull sheet thickness and the electric and magnetic properties of the ship and the model, respectively. There have been performed a large volume of triaxial measurements of the magnetic signature, to acquire the magnetic field distribution for an horizontal plane situated below the hull, at reference depth. Based on the analysis of magnetic signature components of the model ship, some conclusions regarding their shape can be drawn.

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QUAY TRANSFER OPERATION ANALYSIS FOR A CONTAINER TERMINAL

LOKE K.B.; A.H. SAHARUDDIN; M.R. OTHMAN; I. RIZAL; A.S.A.KADER; A.M.ZAMANI

10/1/2014

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

A lot of studies focused on quay transfer operation efficiency. It emphasized on increasing the handling rate and improving the performance by mathematical, modeling or empirical study. Therefore, this study aimed to study delay factors of quay transfer operation in a container terminal, which affected the productivity performance. It tried to overcome the shortcoming of previous studies. Quay transfer operation is one of the operation systems in container terminal, which is affected by many factors and also affected other operations. The delays of the operation will slow down the handling performance and increase the handling time and cost. Hence, an extensive observation and survey activities were done in Malaysian container terminal. The data obtained from relevant respondents that involve in operation. The initial result showed that waiting for prime mover ‘often’ occurred on quay transfer operation. Delay of quay crane and prime mover break downs ‘moderately’ delay the operations. However, waiting for game plan ‘seldom’ affected the operation. Therefore, this study concluded that the handling equipment is the main cause of delay in quay transfer operation in a container terminal.

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CONTAINER YARD OPERATION ANALYSIS FOR A CONTAINER TERMINAL

LOKE K.B.; A.H. SAHARUDDIN; A.R. IBRAHIM; I. RIZAL; A.S.A.KADER; A.M.ZAMANI

10/1/2014

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

This paper studied the key delays factor of container yard for a container terminal. It explored the key delays factor that affected the operating performance of container yard operation. Hence, a survey is conducted and analyzed by SPSS. Descriptive analysis, normality test and reliability test are used to analyze and display the result. The initial result showed that rubber tyred gantry crane, turning for 90o and waiting for prime mover are often happened during the container yard operation. As a conclusion, the handling equipment is the main cause of the delays factor.

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LOADING OF SCRAP-METAL ON SHIP OF «COASTER» TYPE

Vitaliy KHOMYAKOV; Victor SAVCHUK

10/1/2014

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

The article is devoted to the technology of carrying of scrap metal on coasters. Scrap metal, being the cargo, possesses characteristics, which should be taken into consideration by navigator at ship loading. The peculiarity of such category of cargo is relatively serious stowage factor. The pile of scrap metal contains various metal components and items of different shape, size and weight. The observations during the voyage have allowed the determination of the following fact: when grab tears some scrap metal off the pile, it destroys or straightens the parts of the cargo that have lain affected by the pressure forces, and while being loaded into the hold, they may change shape and size. This phenomenon is noticed, when the cargo consists of spring products, wire, tin plates and deformed sheet metal. At present to reduce the loss of the space of the hold at the loading of scrap metal the technology of its “compression” with grab, press or other devices is used. The maximum attention should be paid to the process of “compression” as very often it becomes the reason of underloading of the vessel with the scrap metal. At the designing of the coaster vessels for the future fleet the constructive characteristics of the hold are suggested to be reviewed. The possibility to install the special moving metal bulkhead should be foreseen. It will allow making this fleet more specialized and adapted for the carrying of two or more kinds of scrap metal, bulk cargo simultaneously. The ship-owners will obtain wider opportunities for the exploitation of the new fleet at different freight markets.

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FINITE DIFFERENCE TIME DOMAIN METHOD FOR ACOUSTIC WAVES IN ATTENUATE AND ABSORPTIVE MEDIUM FOR LAYERED UNDERWATER ACOUSTIC ENVIRONMENTS

Jawad LAKZIZ; Sofiane OTMANE; Said OUASKIT; Rachid El GUERJOUMA

10/1/2014

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

In this work, we use Finite Difference Time Domain (FDTD) method to investigate the underwater acoustic wave propagation problem; in order to understand the acoustic wave propagation properties and determining the effects of the attenuation and absorption for the sound intensity in the sea. The results are presented for calculated Transmission Loss (TL) of propagating acoustic waves in layered underwater acoustic environments by using Finite (FDTD) method. In a first step; the sea environment are modeled as one layered medium before generalizing the resolution to two layered (fluid-fluid and fluid-solid) medium. The sea surface and the sea bottom are considered to be planar surfaces. The discretized acoustic wave equations are used in the algorithm of the FDTD method and Perfectly Matched Layer absorbing boundary condition is applied to eliminate numerical reflections from the ends of the grid .Two cases are discussed (Taking account of absorption and attenuation).The good performance of this method is validated with the results of BELHOP program and by comparison with the analytical method.

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SPECIFICS OF CHEMICAL TANKERS FLEET AND ITS MARKET OUTLOOK

Gunes ERGUN; Dimitar DIMITRAKIEV; Aleksandar SIRAKOV

10/1/2014

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

This paper introduces a general outlook of the chemical tanker market and examines the performance of chartering contracts over the period 2008 to 2013. The number of the liquid chemical cargoes has increased enormously since at the early days, the tanker market was expressing only for carriage of petroleum products. As long as the number of the carriage of chemical cargoes by sea are growing up rapidly, the study aim is to clarify peculiar and main characteristics of these tankers. Although, the big part of these chemical cargoes are extremely dangerous to the environment as well as to the life of the seafarers, it may be considered as a small risk due to the very high standards required regarding safety. Apart of the technical point view, the chemical tanker market is forecasted and expected to recover and improve in/after 2014. The main evidence for this theory is that declining fleet growth, shrinking tonnage growth and increasing seaborne trade. Due to these influences, the market gives positive forecast for its short and near future. However, the chemical products market is still weaken enough and presently demand is still shaky, but due to the limited order books, it could be considered as a positive sign in medium period. Nevertheless, the fleet is still in overcapacity and expectations for improving is at the end of 2014 or later on. The purpose of this paper is to study on the present market and strive to forecast the future chemical tanker market situation

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THE CHALLENGE OF BUILDING GREENFIELD TERMINALS

Valentina GRANCHAROVA

10/1/2014

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

The challenge for the container terminals now is to serve fewer but very large calls. The large cargo quantities to be handled in a short period of time are a challenge for the whole chain from ship to gate. The newly build terminals (greenfield terminals) should have lower environmental impact and high rate of automation and energy efficiency. Therefore terminal and process automation has been steadily gaining ground over the last decade and are unalterable part of today’s container terminal. Automation is a credible option offering new possibilities for operational control and visibility with reduced operating costs and enhanced service excellence. The choice for terminal concept and building of terminal operation system especially in greenfield terminals influence for the future extension of the terminal. Both mainly depend on the size of vessels, which are planned to anchorage at the terminal berth and on expected cargo flow through the terminal for certain period of time.

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IMPLEMENTATION OF INNOVATIVE METHODS FOR STUDYING COLREG RULES

Dimitrov DIMITAR

10/1/2014

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

The ship incidents are related to the loss of human life, significant damage to the marine environment and loss of load. They depend on hydro-meteorological conditions, the density of ship traffic, and the condition of the hull and skills of the officer of the watch. The convention STCW sets various requirements regarding mandatory learning and training of navigators for obtaining the relevant knowledge and skills. Despite of modern technologies for facilitating of navigational watch the number of collisions did not decline. The last IMO bulletin reports that more than 90 percent of collisions are resulted from the human factors: initiated by human error or associated with human error as a result of inappropriate human response. This fact put a question for applying appropriate methods for teaching and training of seafarers in COLREG. The paper propose innovative method for understanding, application and testing of COLREG of navigational officers.

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NEW PUBLICATIONS OF THE UNITED KINGDOM HYDROGRAPHIC OFFICE

Dachev YURIY

10/1/2014

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

The IMO’s Maritime Safety Committee at its 86th session from May 26 to June 5, 2009 approved new regulations, on which is written that all merchant ships engaged on international voyages are obliged to be fitted with ECDIS(Electronic Chart Display and Information System) schedulely to the middle of year 2018 as the main means for navigation for working with maritime Electronic Navigational Charts (ENC). Therefore United Kingdom Hydrographic Office issued new Admiralty publications, related to implementation, operation and service of ECDIS, and to content, used symbolic and way for making corrections of Electronic Navigational Charts. The Hydrographic Office also made important changes in the content of some existing publications, which deserve to be discussed in this article. After 2012 the exterior design of all Admiralty maritime publications has been changed. This fact shows clearly that comes one new stage in the publication activity of the United Kingdom Hydrographic Office.

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THE HARDNESS OF SUPERFICIAL LAYERS OBTAINED THROUGH ELECTRICAL SPARKING WITH HARD CARBIDE ELECTRODES AND SOFT MATERIALS

Mihaela-Luminița - BARHALESCU

10/1/2014

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

The work entitled “The hardness of superficial layers obtained through electrical sparking with hard carbide electrodes and soft materials”, presents the research done by the author in regards hardness increase of superficial layers obtained through impulses electrical discharges. This increase appears because of the thermal effect of pulsed discharges. The aria of material which is under the deposited layer is subjected to a pronounced heating followed by rapid cooling by taking over the heat from the base material. In this way occurs a hardening of metallic material located in close proximity to superficial layer deposited.

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ELABORATION AND TESTING OF LABORATORY STAND FOR FREQUENCY CONTROL OF PERMANENT MAGNET SYNCHRONOUS MOTORS

Bohos APRAHAMIAN

10/1/2014

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

The paper presents our work in elaboration and testing of laboratory stand for frequency control of permanent magnet synchronous motors (PMSM). These motors are increasingly finding application in ship electric drives.

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ECOTOXICOLOGICAL ASSESSMENT IN SOME POINTS OF THE ROMANIAN BLACK SEA COASTAL ZONE

Mirela- Iuliana SUNDRI

4/1/2014

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

An ecotoxicological assessment on four points of the Romanian Black Sea coastal zones ecosystems was done using a 72 h algal growth inhibition microbiotest. Water samples toxicity has been tested on the Phaeodactylum tricornutum. Inhibition of algal growth ranged between 2% and 17%. Generally, Phaeodactylum tricornutum shows adaptability tendency to the specific conditions of the investigated areas during the time of the test.

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THE ANALYSIS OF SHORT-CIRCUIT CURRENTS IN A NAVAL ELECTRICAL NETWORK BY MEANS OF SOFTWARE TOOLS

Gheorghe SAMOILESCU; Georgiana MARIN

4/1/2014

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

Short circuits in naval electrical networks are complex phenomena affecting all electrical equipment due to the short length of circuits. The calculation of short circuit currents and their taking into account, ranging from design to the operation of naval equipment and installations, ensure the equipment reliability and optimization. Based on industry standard data, the paper analyzes the management of a particular ship power system, by performing the short-circuit current calculation based on a software tool, particularly designed for this purpose.

THE ASSESSMENT OF CONVECTIVE COEFFICIENT OF HEAT TRANSFER IN EVAPORATORS WORKING WITH R 134a, USING KANDIKLAR EQUATIONS

Daniela-Elena MITU

4/1/2014

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

Heat transfer devices play important roles in the improvement of refrigeration systems performance and for this reason their design is a challenge for engineers. This paper deals with the assessment of convective coefficient of heat transfer in evaporators from one stage vapor compression systems working with R 134a, using Kandiklar equations. The general simple equations for heat exchanger analysis are introduced inside tube refrigeration evaporation where heat transfer correlations for thermal design are given. The sizing methodology of these type of heat exchangers are briefly discussed and a thermal design exemple is presented. The heat exchanger design provides missing information based on experiences, judgment and the requirements of the customer.

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CONSIDERATIONS ON THE PERFORMANCE OF SINGLE VAPOR COMPRESSION CYCLES WITH SUPERHEATING AND WITHOUT SUBCOOLING

Feiza MEMET

4/1/2014

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

In this paper it is evaluated the global performance of an one stage vapor compression cycle with superheating and no sub cooling, calculated as the ratio between refrigerating capacity and electrical power supplied to compressor (COP). It is stated that the superheating of the refrigerant in vapor state occurs inside the refrigerant space. This phenomenon is spontaneous and useful for the protection of the compressor. Since the ban of Hydrochlorofluorocarbons (HCFCs), Hydrofluorocarbons (HFCs) are used as alternative, one of the most visible in marine refrigeration being the non ozone depleting R134a. But the environmental issue does not only include the ozone layer; there is also an increasing worry about the global warming potential due to greenhouse effect. This is why the objective of this work is oriented on the performance of an one stage vapor compression cycle working with R134a and two more refrigerants, having lower GWP. These are R290 and R152a. The analysis for specific conditions will reveal that even if R152a has higher GWP than R290, its COP is better than R134a and R290.

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ANALYSIS OF SHIP OPERATION FOR A CONTAINER TERMINAL

LOKE K.B.; A.H. SAHARUDDIN; A.R. IBRAHIM; I. RIZAL; A.S.A.KADER; A.M.ZAMANI

4/1/2014

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

This study is looking for delay factors of ship operation in a container terminal. Ship operation is a complex process that is affected by many factors, such as weather delays, vessel delays and stevedore delays. These factors will slow down the handling performance and increase the handling time and cost. Hence, secondary data is collected from Malaysian Port and analysis by SPSS. Correlation and pie chart are used to analysis and display the result. The initial result showed that the main cause of delay is stevedore delays (82.60%) and have high correlation with berth turnaround time (0.831). This study further analysis stevedore delays; the results showed that waiting for prime mover is the main delay factor, which contributed to about 41.2% that affected the performance of ship operation. It also has high correlation with berth turnaround time (0.716). Therefore, this study concluded that the stevedore delays and waiting for prime mover is the main cause of delay in ship operation in a container terminal.

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