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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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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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Optimising The Reference Point Within A Journal Bearing Using Laser Alignment

Author(s): Guixin Fan,Natalia Nikolova,Kiril Tenekedjiev,Ty Aaron Smith / Language(s): English Issue: 7s/2021

This paper observes different alignment conditions in a journal-bearing-supported machine (i.e. propeller bearings within the stern tube of a marine vessel). A test rig is built so that the driven machine has fixed supports, roller bearings in an electrical motor. An alignment tolerance is met at the coupling of the journal, which is positioned within three journal bearings. This research can be applied to any industry with machines of the same characteristic. The journal bearings are designed to simulate the large tolerance seen in a vessel’s stern tube only for lubrication control oil is used for the bush bearings. Various sensors are placed on the test rig to record data for later machine analysis. Using proximity probes and accelerometers the vibration of the journals and ball bearings can be visualised using orbital plotting and Fast Fourier Transform (FFT) through both LabVIEW and MATLAB respectively. Four alignment procedures are applied to the coupling using a laser unit. The first two will be so that the offset and angular misalignment is produced in the FFT spectrums as per ISO10816 Mechanical vibration so that a reference point is formed for the test rig. The other two alignment procedures represent current industry practice. These procedures are then compared to see which is the preferred reference point that will optimise the reliability value of a whole system. Finding the procedure with minimal vibration will increase the design life of housing structures for such machines, which will increase the overall profit of the shipping industry. Our developments and procedures will be further utilized in practical classes to improve maritime engineering education.

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Some Problems Related To The Exploitation Of Automated Container Terminals

Author(s): Yana Gancheva / Language(s): English Issue: 7s/2021

Automation is considered as the basis for the introduction of the fourth industrial revolution in ports and for the implementation of a number of innovations. Often the actual results of container terminal automation do not match the expectations of terminal operators. Through the application of scientific methods of investigation – monitoring, comparative analysis, analysis and synthesis of existing publications on the subject – some problematic issues have been established, such as the lack of common standards, pressure by trade unions, processing of exceptions, etc., calling into question the implementation of any good automated terminal project. The synergistic approach in the modeling, construction and exploitation of automated container terminals leads to the conclusion that, on one hand, a solution to the above issues should be sought in the cooperation between all port stakeholders (automation system manufacturers, software developers, terminal and logistics operators, carriers). On the other hand, the competitiveness of automated container terminals depends on the skills of the port specialists. They must be prepared for the monitoring, analysis and management of automated systems, they must be adequately qualified for the integration of systems and for the processing of exceptions, they must be able to foresee the consequences of each of their actions for the whole system.

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Green Ports – Environmental Challenges And Economic Demands

Author(s): Georgi Gilev,Dimitar Dimitrakiev / Language(s): English Issue: 7s/2021

The article defines the term Green Ports as a part of logistics chain and the transport networks are under sustainable development and process optimization. Port expansion should always be considered in the context of environmental legislation and its implementation in different national laws.

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Multilevel Demand For Sea Transportation. Correlation Between Baltic Dry Index (Bdi) And Coaster Shipping Prices For Sea Routes Between Baltic Seaports And Mediterranean Seaports

Author(s): Svetlana Dimitrakieva,Ognyan Kostadinov,Christiana Atanasova / Language(s): English Issue: 7s/2021

Baltic Dry Index (BDI) reflects the prices of sea transport performed by Capesize, Panamax, Supramax and Handysize bulk carriers only. The prices of the transport with vessels of smaller tonnage are not considered in the calculation of BDI, therefore principally it should be assumed that BDI does not refer to a tonnage different from the observed. On the other hand, the demand for maritime transport services depends on the state of international trade of goods. Generally, the international market of goods is common for all ship types and tonnages. In the production processes starting from the extraction of raw materials till the sale of finished products to end customers; it can be done by several transport carriages in succession, which provide the intermediate production stages. Transport demand is secondary and depends on international trade, but on the other hand, this demand is multilevel. From an economic point of view, it is important to study the interrelationships between maritime transport providing the intermediate production stages, from the extraction of raw materials till the sale of the final goods.

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Review Of The Current Increase Of Noise Unit Cost Values In Transport

Author(s): Luka Vukić,Ivan Peronja,Mihaela Bukljaš,Alen Jugović / Language(s): English Issue: 7s/2021

Until recently marginalized, noise pollution has become a significant source of external transportation costs. Noise costs have currently reached a respectable share of 7%, an increase of 3.5 times in the last five years. No other item of external transport costs shows even close to such growth, and the total increased by only 8% in the same period. Raising awareness of the harmfulness of this kind of contamination has contributed to better perception and detection of noise. Stricter and more thorough valorization of traffic noise has led to an increase in the share of external noise costs. Using or installing expensive noise protection equipment and new knowledge about the noise harmful effects on health contribute to the same trend. Noise pollution should be considered as an obligatory item in the assessment of sustainability in modern transport today.

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Target Detection For Visual Collision Avoidance System

Author(s): Miro Petković,Danko Kezić,Igor Vujović,,Ivan Pavić / Language(s): English Issue: 7s/2021

Automatic Identification Systems (AIS) and Automatic Radar Plotting Aids (ARPA) are commonly used to detect targets for collision avoidance. However, AIS cannot detect targets without AIS transmitters and ARPA has limitations due to blind sector and small targets may not be detected. Advances in computer performance and video-based detection generated much interest in developing intelligent video surveillance systems to achieve autonomous navigation. To develop a reliable collision avoidance system, we propose the use of a visual camera for real-time object detection and target tracking. Moreover, the system should follow the International Regulations for Preventing Collisions at Sea (COLREGs) to avoid catastrophic accidents. In this paper only a part of the system is presented. For real-time object detection, the You Only Look Once (YOLO) ver. 3 convolutional neural network is used, and the target tracking filter based on a Kalman filter with built-in estimated relative position and velocity.

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New Results For Teaching Ship Handling Using Fast Time Simulation

Author(s): Knud Benedict,Michèle Schaub,Michael Baldauf,Michael Gluch,Matthias Kirchhoff,Caspar Krüger / Language(s): English Issue: 7s/2021

Some years ago, the SAMMON software tool box was introduced for “simulation augmented manoeuvring design, monitoring & conning”. It is based on the innovative “rapid advanced prediction & interface technology” (RAPIT) to simulate the ships motion by fast time simulation FTS with complex dynamic math models and to display the ships track immediately in an electronic sea chart for any rudder, thruster or engine manoeuvre planned by the navigator. Specifically, the SAMMON planning tool will be shown in its opportunities for achieving new knowledge for teaching of ships dynamic and training of ship handling elements. That system represents the full information from ships’ manoeuvring documentation and from additional trial results squeezed in a ship dynamic model, capable of simulating environmental effects by using the RAPIT technology. The paper introduces the variety of opportunities of the training tools by presenting use case studies, e.g. For drifting under wind and how to get simple formulas for drift speed related to wind speed. Additionally, two complex manoeuvring strategies for a port arrival scenario will be compared for a ship with azimuth propeller to find out potential alternatives with less fuel consumptions and emissions.

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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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Applicability Of The Ooda Loop Theory For Analysis Of Human Error Processes In The aritime Safety

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

The publication evaluates the applicability of John Boyd's OODA Loop (observe-orient-decide-act) theory for the analysis of human error in the maritime industry. The predominant share of human error among the range of maritime safety issues is revealed. The interdependence between the different phases of the OODA Loop to achieve the desired state of maritime safety is studied, namely the correct actions in each of the implemented cycles. So, the paramount importance of situational awareness as a prerequisite for safety is proven. The mechanisms for manifestation of other factors endangering maritime safety are also analyzed, such as: lack of competence, fatigue, stress, etc. In conclusion, the role of the time factor in the realization of the OODA Loop is assessed and in this context, approaches are offered to increase the possibility for realization of a quality loop.

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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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