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Air Pollutant Emission Measurement

Author(s): Nicola Račić,,Branko Lalić,Ivan Komar,Ladislav Stazić,Frane Vidović / Language(s): English Issue: 6s/2021

One of the main methods for estimating air pollutant emissions from ships is the method developed by Carlo Trozzi, which was later accepted and recommended by the European Environment Agency in its air pollutant emission inventory guidebooks. Consequently, it has become the most commonly used methods for making inventories of air emissions in the shipping industry and for predicting future trends. The method and its equations use emission factors to calculate the emission of air pollutants from ships. Emission factors are calculated depending on fuel consumption or main engine power; results are given for different year of manufacture and engine speed. This paper presents the measurement of air pollutant emissions and some other parameters on marine engines operating in different conditions. The measured values are calculated to obtain values which will enable the next step, the comparison with the emission factors in the latest guide of the European Environment Agency on the inventory of pollutant emissions.

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Swarm Of Autonomous Underwater Vehicles – Preliminary Results Of The Control System

Author(s): Tomasz Praczyk,Tadeusz Bodnar / Language(s): English Issue: 6s/2021

A swarm of autonomous underwater vehicles can be a valuable alternative for fully equipped and very expensive super-vehicles. A distributed system of tightly cooperating vehicles can be cheaper, simpler in maintenance, more reliable, more flexible and universal than traditional single-vehicle systems. However, keeping a tight formation of underwater vehicles in the condition of the sea current, unclear environment, and rare inter-vehicle communication is a very challenging problem, which requires an effective vehicle control system. The paper proposes a solution to the above-mentioned problem, which is based on neuro-evolution. Moreover, the paper also presents the first results of the proposed system.

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Assessment Of Lng Bunkering Accidents

Author(s): Peter Vidmar,Andrej Androjna / Language(s): English Issue: 6s/2021

The maritime safety is of great concern for the entire maritime community. Ships using LNG for propulsion are already sailing the seas, but the majority of the ports are not yet prepared for this kind of supply. As the process of LNG bunkering is only seemingly similar to traditional oil bunkering or liquid loading, dealing with the technical and safety challenges is much more subject of investigation. In this paper, the dispersion part of the consequences of LNG release, pooling, evaporation and dispersion during the future bunkering operation in the port of Koper, Slovenia, where the populated area (city) is located in close proximity are examined. We follow the comparison of three different tools, namely the Unified Dispersion Model (UDM) implemented by the software PHAST from DNV-GL® and two CFD (FDS – Fire Dynamics Simulator from NIST and Ansys Fluent) in the same case scenario. Geometry, initial and boundary conditions are assumed to be the same as far as possible, according to the limitations of the respective software tools.

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EGR Operation Influence On The Marine Engine Efficiency

Author(s): Delyan Hristov,Ivan Ivanov,Dimitar Popov / Language(s): English Issue: 6s/2021

In the work presented, the focus is on the influence of the EGR operation on the engine performance factors. Basic principles of the EGR operation are considered and experiment with electronically controlled engine is carried out on a Kongsberg marine simulator. The influence of the EGR on the efficiency, specific fuel consumption and CO2 emissions is evaluated. Recommendations for the performance adjustment of the supercharging system are stated.

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The Reliability Of Watertight Longitudinal Girders Of Fuel Tanks On Aging Bulk Carriers

Author(s): Spiro Ivošević,Nataša Kovač / Language(s): English Issue: 6s/2021

During the exploitation of bulk carriers, the condition of structural elements and areas depends on the type of the cargo transported, operational conditions and maintenance systems. Corrosion significantly accelerates the aging of metal plates and girders thus causing the deterioration of steel surfaces, which consequently reduces the reliability of structural elements, areas and ships in general. The damage to metal structures can impair the stability of a ship, reduce longitudinal strength, cause the ingress of water into the hull as well as environmental pollution through fuel spills from the tanks. Therefore, the paper analyzes a part of a double bottom structure based on the available wear data on watertight longitudinal girders of fuel tanks. The research included 25 bulk carriers aged between 5 and 25 with the total of 110 fuel tanks. The reliability analysis of steel plates included the total of 1920 data measured. The allowable wear of structural plate thickness that equals 20% of the original thickness value was determined by the application of the acceptance criteria that were prescribed by classification societies. The calculations of the function of failure density, failure intensity and reliability determined the time when the condition of structural elements deteriorates due to corrosion up to the levels that require extensive maintenance services.

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The Measurement Of Exhaust Gas Emissions By Testo 350 Maritime – Exhaust Gas Analyzer

Author(s): Bruna Bacalja,Maja Krčum,Tomiskav Peša,Marco Zubčić / Language(s): English Issue: 6s/2021

This paper presents the measurement process of the emissions from marine diesel engines. The emission measurement was carried out by the certified TESTO 350 Maritime exhaust gas analyzer on the Juraj Dalmatinac ferry Caterpillar C32 engines. The gas analyzer records the concentrations of nitrogen oxides (NOx), carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2) and sulfur dioxide (SO2). TESTO 350 emission sampling probe was set at the end of the exhaust pipe. A combustion emission measurement was performed during a Split – Supetar (Brač) trip and backwards with the total duration of 110 min. The emissions are estimated for two trip phases: “maneuvering” and “at sea”.

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Contribution To The Reduction Of The Ship’s Switchboard By Applying Sensor Technology

Author(s): Nediljko Kaštelan,Marco Zubčić,Maja Krčum,Miro Petković / Language(s): English Issue: 6s/2021

The paper discusses the contribution to energy efficiency by reducing the dimensions of the main switchboard (medium voltage or High Voltage – used on ship). Reducing the dimensions of the switchboards can be achieved by reducing the dimensions of the bus bars, while fully satisfying the conditions with regard to thermal and mechanical stresses. The same can be achieved by modifying some other components, such as the application of new technology for measuring current and voltage, using current and voltage sensors that fall into the category of completely new technological solutions. By replacing conventional measuring transformers (IT), compact and efficient sensor technology significantly contributes to reducing the dimensions and mass of switchboards, which ultimately contributes to energy efficiency. Previous applications, the possibility of improving existing solutions, especially in applications in marine power systems, and new technological solutions that contribute to the efficiency of the marine power system using the Rogowski coil sensor and voltage divider voltage sensors are also considered.

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Introduction Of 3D Printing Into Marine Electrical Engineering Education – A Case Study

Author(s): Ivica Kuzmanić,Igor Vujović,,Zlatan Kulenović,Miro Petković / Language(s): English Issue: 6s/2021

The research on 3D printing aboard ships is already under way. The private sector and the navy are both experimenting with its usage. This type of education is however missing in mariner education (e.g. Electrotechnical Officer) and in International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) alike. Various authors have proposed that 3D printing should be included in the STCW standard courses. This paper describes an example of introduction of 3D printing into marine electrical engineering education at the Faculty of Maritime Studies in Split. The class is mandatory for this study. This is performed through “learning by doing” technique.

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Modeling Of The Dependence Of The Produced Amount Of Hydrogen Gas (Y) On The Amperage Of Cell (X) Of A Marine Diesel Engine Skl 3Nvd24

Author(s): Hristo Hristov,Ivailo Bakalov,Bogdan Shopov,Dobromir Yovkov / Language(s): English Issue: 6s/2021

The introduction of new fuels in the field of maritime transport is considered a serious challenge due to the harsh environmental conditions in which the motor ship must operate. Modern marine engines are designed to improve the overall efficiency of the marine system so any attempt to exploit a new fuel must be accompanied by scientific research and experimental data to provide engineers and ship operators with sufficient information on its efficiency and safety.

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Shipyard Crane Modeling Methods

Author(s): Pawel Piskur,Piotr Szymak / Language(s): English Issue: 6s/2021

The article discusses various crane mathematical modelling and simulation methodologies. The purpose of this study is to assess the effect of wind force on the dynamic of shipyard cranes, particularly hook movements in the horizontal plane. Appropriate simulation models are required to offer a robust control strategy that allows the crane to be remotely operated in windy circumstances. As a result, mathematical models based on differential equations for varying numbers of independent variables are compared to object-oriented, physical modelling model based on Matlab Simscape Multibody. The assumptions are explored, as well as the effect of the number of independent variables on model correctness.

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S-101 Charts, Database Tables for S-101 Charts, Autonomous Vessel

Author(s): Vladimir Brozović,Danko Kezić,Rino Bošnjak,Filip Bojić / Language(s): English Issue: 7s/2021

This article shows a way to store the data of many S-101 charts into a single Postgres database. The data model of the database with all tables is shown and explained. The concatenation of the indices from the different database tables is explained. This concatenation allows for a faster search of points/curves with certain properties. This fulfills one of the basic requirements for the purpose of navigating an autonomous vessel – that several charts can be interpreted simultaneously by a machine. Mechanisms for up-dating the database with new charts not yet present in the database are shown. Also the mechanisms for updating the charts already present in the database are explained. System limitations are briefly presented to show that in practical use there are in fact none. Memory requirements for such a type of chart storage in the database is compared with memory requirements for ISO8211 files normally used for storage of S-101 charts. With small examples it is finally shown how the stored chart information can be searched specifically.

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Influence of Hydro-meteorological Elements on the Ship Manoeuvring in the City Port of Split

Author(s): Zvonimir Lušić,Nedad Leder,Danijel Pušić,Rino Bošnjak / Language(s): English Issue: 7s/2021

t The Port of Split is located in the central part of the eastern Adriatic and is the largest Croatian passenger port. The Port of Split consists of the North Port, for the reception of mainly cargo ships, and the City Port for the reception of passenger ships. Although the port is protected from the open part of the Adriatic by a number of islands, its specific spatial position as well as local hydro-meteorological factors, primarily wind, can significantly affect the safety of navigation, and ultimately close all traffic. The entrance to the City Port is facing to the south; accordingly, the effect of southerly winds and waves will be one of the primary factors influencing the safety of manoeuvring. Also, the wider area of Split is characterized by the strong local, approximately NE wind with sudden gusts (‘’Bura’’) which is especially dangerous for navigation. This paper analyses the effect of significant hydro-meteorological factors on the safety of manoeuvring at the approach and within the City Port of Split. The influence of wind, waves, sea current, tides and visibility will be analysed. Also, these factors will be classified in order of importance with respect to those parts of the port where they predominate as a threat to manoeuvring safety. The obtained results should serve as a basis for future defining of limiting working/manoeuvring conditions.

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Meeting Sustainable Development Goals – Experience From The Largest Shipping Companies

Author(s): Katerina Balić,Helena Ukić Boljat,Merica Slišković / Language(s): English Issue: 7s/2021

The UN agenda for Sustainable Development underlines the importance of balanced and integrated environmental, economic and social development through 17 goals. The role of the shipping industry in achieving the sustainable goals is recognized and highlighted by UN. As shipping companies are one of the most important stakeholders in the global economy and maritime transport, sustainable goals must be integrated into their continued operations and development. This paper aims to analyze the commitment of the largest shipping companies to the Sustainable Development Goals (SDG). From their annual reports for 2019 and 2020, an analysis of the commitment to SDG was conducted. The analysis shows that the majority of the companies comply with the SDG and embed them in their daily business processes.

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Traditional vs Online Education In the Maritime Training System Under Covid-19 Pandemic: Comparative Analysis

Author(s): Olena Bezlutska,AIona Leshchenko / Language(s): English Issue: 7s/2021

The correlation between traditional and MOODLE learning management system usage in the educational process of the maritime higher education institutions has been studied in the article. The need to find new digital tools was due to the current state of the educational system, which should become open to new trends, and exacerbated by the conditions of the COVID-19 pandemic. Comparative analysis was chosen as the main research tool, which made it possible to conduct a comparative analysis of online and offline modes of implementation of the educational process in higher maritime educational institutions, as well as to determine the main advantages and disadvantages of the LMS MOODLE electronic platform. Her collection of data was carried out using a Google questionnaire. The respondents had to answer 9 questions. The survey was conducted among students of the Maritime Academy of two age categories – from 18 to 30 years old and from 31 to 45 years old. Analysis of the questionnaire data allows us to conclude that students of the first age category have more developed digital competencies (87%) and easily switched to distance learning using the LMS MOODLE platform; however, in the second age category, more than 60% had no difficulties with online learning. In general, for applicants for higher education, working on the LMS MOODLE electronic platform has its advantages and may be one of the methodological tools for the implementation of the educational process. For applicants for higher maritime education, it is convenient both in terms of timing and availability for education. The weak side of the platform is the lack of opportunity for teachers to independently organize (without the technical support of the platform administrator) video lessons on LMS MOODLE in real time, which is one of the priority tasks for improving the educational process online. The next step in the development of online learning opportunities is to create opportunities for teachers to independently create online rooms for lectures and practical exercises in real time, as well as expand the possibilities for connecting cloud simulators to practice the practical skills and abilities of students of higher maritime educational institutions.

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Measurement Of The Dynamics Of The Sheave Block Of Shipyard Crane With 1000 T Lifting Capacity For Verification Of The Laboratory Stand

Author(s): Piotr Szymak,Pawel Piskur,Jacek Goszczyński,Tomislav Batur / Language(s): English Issue: 7s/2021

The paper includes partial results of the development project entitled “The first Polish gantry crane with high lifting capacity for the shipbuilding industry adapted to work in difficult wind conditions – development and demonstration” (no POIR.01.02.00-00-0017/18). Due to the requirements of working in challenging wind conditions, the crane will be equipped with the sheave block with a hook operating automatically. To resolve this problem, mathematical and then physical models of the innovative crane are required. Therefore, to obtain reliable models, the measurement of the dynamics of the sheave block of crane with high lifting capacity was carried out. At the beginning of the paper, the conditions and used measurement stand are included. Then, the time and frequency analysis of the received measurement results are described. Moreover, the determination of the crane parameters is also presented. The analysis results will be used in further research to tune both the simulation and the physical models of the crane with an automatic hook, which are being developed.

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The Regionalization Of European Security And Defense Policies In The Maritime Domain: The Black Sea Case

Author(s): Siyana Lutzkanova / Language(s): English Issue: 7s/2021

The specific regional dynamics of maritime security environment in EU raise the question whether and to what extent the processes of “regionalization of security” need to be implemented within the principles of current CSDP (Common Security and Defense Policy) and European maritime security strategy. Joint civil-military concept of operations on regionalization of CSDP action in different regions like Saher Mali or Sahel Nigeria are good examples of tackling specific regional threats with individual regional approach based on the main strategic interests of the EU. The unification of policies based on international regulations in the maritime domain are examined in the context of the very specific regional aspects of the European national maritime spaces. Some examples of Black Sea maritime security issues are analyzed with the question to which extent basic assumptions of the current CSDP and European maritime security strategy are applicable to the challenges of the current security environment in this region. The levels of sustainability and resilience are connected to the processes of democracy development, some socio-demographic characteristics of the region and even cultural-civilizational aspects. Those assumptions are especially important in the context of state’s resilience capabilities for preservations of basic state functions in times of crisis occurrence and crisis management. Another point is the possibility to use the regionalization security process as “window of opportunity” to set new agenda for possible mitigation of tensions between the Black Sea EU members and non EU-members in the region.

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Od bursztynu do turkusu – perspektywy przeobrażeń systemów zarządzania bibliotekami w świetle doświadczeń uczelni zawodowych

Author(s): Małgorzata Bańkowska (d.d. Całka) / Language(s): Polish Issue: 2/2020

In this article, the modern typology of the organization by Frederic Laloux shall be described, with a particular emphasis on the properties of Teal organizations. Based on the experiences of selected Polish companies within the services and industrial sectors, the original concept of Teal paradigms implementation is described. Factors favoring changes in the library and staff management are described, as well as the stages of their implementation.

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POTENTIAL APPLICATIONS OF ANTIBACTERIAL COMPOUNDS IN EDIBLE COATING AS FISH PRESERVATIVE

Author(s): Maulidan Firdaus,Desy Nila Rahmana,Diah Fitri Carolina,Nisrina Rahma Firdausi,Zulfaa Afiifah,Berlian Ayu Rismawati Sugiarto / Language(s): English Issue: 5/2021

Fish is a product that breaks down quickly due to biochemical reactions that cause a decrease in the quality of its nutritional and sensory values. Natural preservatives make fish safer for consumption than fish preserved with formalin. Edible coating is a preservative that can be eaten, can prevent biological, chemical and physical changes, is able to prevent mass transfer, acts as a moisture barrier, be contained antimicrobial/antibacterial and antioxidants, increases shelf life, as well as protects food from microbial contamination. Antimicrobial/antibacterial compounds added to edible coatings are able to inhibit food degradation and/or remodel toxic compounds such as free radicals. Antimicrobials can be obtained from plant extracts such as alkaloids, flavonoids, saponins, tannins, phenolic acids, and eugenol. These compounds can slow the growth of bacteria in fish namely Escherichia coli, Pseudomonas aeruginosa, Staphylococcus sp., Staphylococcusaureus, Psychrotrophic and Psychrophilic bacteria counts, Enterobacteriaceae, and lactic acid bacteria. This article reviews the application of various antibacterial compounds from various plants that are added to edible coatings as preservatives in fish.

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COATING METALS WITH ZINC AND METHOD FOR MEASURING THE THICKNESS OF THE LAYER

Author(s): Miroslav Minchev / Language(s): English Issue: 5/2021

When a copper coin is immersed with zinc into a solution of a zinc salt (ZnSo4, ZnCl2 etc.) an electrochemical reaction occurs in the mixture. As a result, a thin layer of zinc appears on the surface of the copper which gives the impression for silver color. The purposes of this project are: to explain the phenomenon and to investigate relevant parameters; to measure the thickness of the zinc layer; to determine which metals can be covered with zinc in such experiments. Method for measuring the thickness of the zinc layer was obtained by using dimension properties of the coin – radius, height and mass. The advantage of this method is the fact that it can be applied for all metals whose form has an integrable volume. The thickness of the layer was determined to be in the order of 1 micrometer. The relationship between the thickness of the zinc and the time at which the coin has spent in the solution was also studied and an exponential tendency was observed. It was proved that only metals after hydrogen in the Reactivity series can be plated with zinc with this setup.

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Reconsidering Language Assessment Courses in Teacher Training Programs During and After the COVID-19 Pandemic

Author(s): Ferit Kılıçkaya / Language(s): English Issue: 3/2021

Assessing learners’ performance is crucial as it informs about learners’ achievement levels in addition to their strengths and weaknesses, not only in face-to-face but also in online teaching. The study aimed at investigating the challenges faced by language teachers in assessing learners during online teaching and to offer some suggestions regarding language assessment courses in teacher training programs. The study adopted a qualitative approach to data collection and analysis. The participants included 22 language teachers aged between 24 to 48. Of these teachers, 8 were male, while the rest were female. Their teaching experience varied from 2 to 25 years, with an average of 11.8 years. The data was based on the responses of the participants during semi-structured interviews. The participants were asked to attend ZOOM meetings to be held, considering their availability. The interviews lasted 10 to 25 minutes. The results of the study indicated that the challenges faced by the participants included five major themes: Assessment type, assessment item formats, support, previous training (assessment literacy), and academic integrity. Several suggestions were offered considering online testing and assessment literacy and language assessment courses in teacher training programs.

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