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  • Weintrit, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Navigational charts are essential tools for marine navigation. But how accurate are the navigational charts that we use when going sailing? Do we really know how much faith can be placed in them? All charts, whether paper or electronic, contain data, which varies in quality due to the age and accuracy of individual surveys. In general, remote areas away from shipping routes tend to be less well surveyed, and less frequently, while areas of high commercial traffic are re-surveyed frequently to very high levels of accuracy, particularly where under-keel clearances are small. It is quite accurate to consider a chart as a jigsaw of individual surveys pieced together to form a single image. Having the necessary skills to determine how much confidence should be placed in the surveys, which combine to form a chart, should be a requirement for any sailor venturing into unfamiliar waters. When the International Hydrographic Organization (IHO) developed the S-57 standard for Electronic Navigational Charts (ENCs), this problem was recognized and it was decided that the quality of survey data used to compile ENCs had to be encoded within a composite data quality indicator ‘Category of Zone of Confidence’ (CATZOC) to assist seafarers in assessing hydrographic survey data and the associated level of risk of navigating in a particular area. According to IHO S-67, the accuracy of Electronic Navigational Charts is not impressive and leaves much to be desired. The author discusses these apparent shortcomings of ENCs and present erroneous approaches to this problem, so common in the seafaring community.
  • Muha, Robert; Sever, Drago; Sokolovskij, Edgar (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The article identifies the optimal location of the warehouse distribution centre for Slovenian companies in the international environment. The process of location selection takes into account a series of interconnected factors, including flows of goods between countries; the level of development of the transport system and transport infrastructure; the number of transport companies; labour costs and labour productivity; and the tax benefits existing in each country. Scientific literature mentions various methods for choosing a warehouse location, which differ in complexity and in the use of different qualitative and quantitative factors. However, the methods discussed have a disadvantage in that they use the current input variables when defining the optimal location. Choosing the optimal warehouse location is an important long-term logistics process, which should consider the fact that the environment in which companies operate is constantly changing. Using the proposed approach, future trends in the international environment are presented, which enables a better choice of warehouse location in the long run. Through this approach, companies can save on logistic costs, while also providing better quality logistics services. The analysis represents a starting point for deciding the location of a warehouse, but does not constitute a complete set of guidelines for companies to follow, as the choice of a particular location is dependent upon the complexity of the international environment in which a company operates.
  • Škerlič, Sebastjan (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Companies that operate in the international automotive industry face various cost-related demands, including demands for lower logistics costs. For the purpose of assessing the situation in the field of logistics, a survey was carried out on a sample of Slovenian manufacturing companies that are part of the international supplier chain. The goal of the study is to determine whether the various demands of customers for lower logistics costs have an impact on the business processes of Slovenian companies. The results of the statistical analysis highlight the importance of cooperation between departments within companies when customers demand lower logistics costs and emphasize the importance of introducing innovations in the optimization of these costs. The case study also represents a current reference for other sectors of the economy on the topic of logistics process management and on strengthening relations in international supply chains.
  • Kaya, Ali Yasin; Asyali, Ender; Ozdagoglu, Askin (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Individual career planning plays a key role in achieving success, goals, and ideals in professional life. However, managing to accomplish such favorable results depends on the correct decisions of graduates to choose suitable job opportunities. Oceangoing watchkeeping officers, who are responsible for the management and administration of vessels at sea, have several job options which are differentiated by vessel type, such as; bulk carriers, chemical tankers, general cargo ships, and container ships, etc. This study aims to discuss the criteria that Turkish oceangoing watchkeeping officers take into consideration and the values they attribute to such criteria regarding their vessel type preference. The aim is to provide instructions to oceangoing watchkeeping officer candidates and academicians who are interested in these issues and related parties of maritime industry. Attribution values of the criteria are determined by means of Fuzzy Analytic Hierarchy Process (AHP) and the most preferred alternative vessel type is revealed through Fuzzy TOPSIS methodology. According to the study results, the most important factors are; revenue, perception of occupational health and safety, and labor work density. The most preferred ship type among alternatives is the oil tanker.
  • Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dear Readers, It is my great pleasure to introduce issue 54 (126) of the Scientific Journals of the Maritime University of Szczecin. In this issue, we publish results of current research on marine technology, marine navigation and marine traffic engineering. The introductory article entitled “Optimisation approach in multi-stop routing of small islands” has been prepared by Prof. Srećko Krile (University of Dubrovnik) and Editor-In-Chief of a sister journal, Nase More (Our Sea) – an internationally-renowned specialist in optimising logistics processes. This publication was financed by the Ministry of Science and Higher Education of the Republic of Poland from the fund devoted to popularising science: grant no. 790/P-DUN/2016. I am sure this article will be informative for all readers interested in the issues of increasing efficiency of transport operations at sea. The Marine Technology and Innovation section included articles dedicated to the wear and tear of machine components, security in the oil tanker industry and minimising fuel consumption as well as improving the quality of bunkering services. The Navigation and Maritime Transport section includes articles addressing models of ship traffic as a tool in manoeuvring processes, an attempt to analyse the reliability of navigational charts and a discussion on the performance of GNSS receivers. The Transportation Engineering section includes papers about marine transport engineering. This section provides information on the comprehensive method of formal safety assessment of ship manoeuvring in waterways, shows the use of simulation methods in defining further development of the approach channel to Ystad as well as analyses the efficiency of man overboard manoeuvres. The Miscellaneous section gathers articles addressing the relationship between educational systems and labour markets using an example of the Maritime Management curriculum, as well as an investigation of the underwater noise associated with remotely-operated vehicles. I would like to use this opportunity to encourage authors from all around the world to publish their findings in the Scientific Journals of the Maritime University of Szczecin. I also invite all readers to visit our new website http://scientific- journals.eu/readers, which contains online versions of the current issue as well as archival editions of the journal. Assoc. Prof. Leszek Chybowski Editor-in-Chief Szczecin, 15 June 2018
  • Krile, Srećko (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The routing problem of small island ports is, in many cases, firmly dependent on country topology, e.g., how to connect islands with a main (home) port, where the order of stops can be different, especially if there are not enough passengers or cargo waiting to be transported to or from every port. Thus, we need a capable optimization tool with which we can adapt each route for an appropriate time schedule; for example, some routes in one cycle can touch each island (forwards or backwards) but some routes can be incomplete, to touch only a few of them. The carrier has to find space for price-cutting (lower prices per journey – more passengers on board), to be more attractive in free-market competition. In such route optimization, we have to interconnect minimal transport cost with maximal revenue (money from tickets), which could be a very demanding task (a non-linear objective cost function). Instead of a non-linear polynomial optimization, which can be very complicated and time-consuming, the network optimization methodology could be efficiently applied. The main goal is to find more efficient routes, to decrease expenses and to increase revenue at the same time (dual mini/max problem).
  • Sevgili, Coşkan; Zorba, Yusuf (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Bunkering is very important for the maritime industry because of the need for continuity of trade, its relation to the energy industry and its great economic value. Today, the volume of the world’s bunkering market is around 350 million tons annually. Although there are about 400 major bunkering ports in the world, most of the demand is concentrated in a few strategic ports: when comparing strategic regions of the world, Istanbul has a very small share. With this in mind, this paper aims to demonstrate the current situation of Istanbul and to improve service quality using Fuzzy Quality Function Deployment. Our results show that the criteria which customers look for, in order of importance, are: supply waiting time; bunker quality; usage and availability of barges; duration of bunkering operation; and bunker price and price competitiveness. The steps to be taken to improve service quality are determined as: increase storage facilities and capacities; create a structure that can provide 24/7 bunker supply; and increase importance of bunkering in port infrastructure and management thinking (bunker port concept). It is possible that the findings can be a guide to ship fuel suppliers, especially in Turkey, to improve service quality and increase their fuel sales volume.
  • Sharifov, Zahid; Aliyev, Chingiz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The article deals with the influence of surface roughness, processed by various technological methods, on the wear-resistance characteristics of the surface layer of high-precision parts of ship machinery and mechanisms. It considers various technological methods of processing parts; rotary cutting, grinding with vibration damping, rotational honing, grinding with metered removal of surface material and elastic rolling. It was found that the application of rotational boring as a method of finishing not only forms an additional, highly wear-resistant surface layer on the surface of the parts, but also provides high productivity. The process of grinding with vibration damping significantly reduces the transfer of abrasive particles to the surface being treated, and improves the accuracy, quality and wear resistance of the surface layer. On rotational honing, the discontinuity of the cutting of individual grains is combined with the continuity of the chip formation process; the metal does not adhere to the working surface of the cutting part of the tool, and the temperature in the cutting zone decreases, resulting in a high-quality, wear-resistant surface layer on the parts. When lapping with dosed removal of the material of the surface layer, the optimum thickness of the highly-deformable surface layer is ensured, due to the possibility of controlling the abrasive action on the surface to be treated, which promotes the formation of a reliable, wear-resistant layer. Elastic rolling allows processing of non-rigid, thin-walled parts by stable, balanced, controlled forces, without reducing their accuracy, quality and wear-resistant characteristics.
  • Urbanowicz, Kamil; Firkowski, Mateusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Pressure pipes made of selected plastics are widely used in current water supply systems. Unfortunately, the theoretical basis for modeling transient flows in these pipes has not been clarified yet. For simplified one-dimensional numerical modeling, a model is commonly used in which the total deformation of the pipe walls is expressed by the sum of instantaneous and retarded deformations. One of the main problems lies in the correct experimental determination of the creep function defining the properties of the polymer. The influence of other parameters on which the numerical solution of the method of characteristics is based is the subject of the research presented in this paper
  • Januszewski, Jacek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Nowadays (August 2017) position data can be obtained generally from satellite navigation systems (SNS), such as GPS and GLONASS, and satellite based augmentation systems (SBAS) which can be either global, such as EGNOS, GAGAN, MSAS and WAAS, or regional, such as NAVIC (IRNSS) in India. Two new global SNSs, Galileo and BeiDou, three new global SBASs, SDCM, KASS and SNAS, and one new regional SBA, QZSS in Japan, are under construction. The generic name given to all these abovementioned systems is GNSS (Global Navigation Satellite Systems). This paper presents details of the following: changes that have occurred in the cumulative core revenue in different GNSS market segments (road, Location Based Service LBS, surveying, agriculture, timing & synchronization, aviation, maritime, drones and rail in 2017) in the last 8 years; an overview of the GNSS industry and location-based services in the world; details of current and future GNSS market evolution; GNSS unit shipments in 13 different categories of maritime application; the frequency and constellation capabilities of GNSS receivers; GNSS frequencies that will be common in the future; the adoption of multi-constellation, multi-frequency and dual-frequency as key enablers of improved accuracy and integrity; GNSS services available for civil and authorized users, and multiple signals in the case of all four global SNSs.
  • Vidmar, Peter; Perkovic, Marko (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The paper presents the overall risk management state for the crude oil tanker fleet, evidenced by EMSA and other international marine organisations. Based on historical statistical data related to fleet size, accident reports, amount of oil spilled on the sea and the economic value of the crude oil transport business, the risk acceptance criteria are evaluated. The Formal Safety Assessment is further used for a systematic assessment of risk, where potential hazards are analysed with structured methods (HAZID) and represented in event trees. The paper studies three risks: PLL (potential loss of lives), PLC (potential loss of containment) and PLP (potential loss of property). A general approach is presented and discussed with a particular focus on the evolution of risk acceptance in recent decades and evaluations of risk F-N curves for different tanker sizes.
  • Kasyk, Lech; Kijewska, Monika (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Vessel passage speed is one of the parameters describing the vessel traffic stream on a selected waterway. Knowing the probability distribution of vessel passage speeds is essential for modeling vessel traffic streams on a waterway. This article undertakes probabilistic modeling for vessel speeds in restricted areas, where the distribution of the vessel passage time of the waterway section is known. The probabilistic procedure of the inverse random variable is used. Four different cases are considered. First, the probabilistic distribution of the vessel passage speed is given, where the vessel passage time is described by the normal distribution in certain restricted areas. The next three cases present the probabilistic distribution of vessel passage speeds on the Szczecin–Świnoujście fairway, where the vessel passage time is described by the extreme value distribution, the Frèchet distribution and the Weibull distribution.
  • Łącki, Mirosław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The goal of research presented in this article is to check if a neuroevolutionary method with direct encoding is able to be a part of autopilot of the vessel. One of the important tasks of vessel autopilots is to keep a course as straight as possible or to bring the ship back on the route as efficiently as possible. In this paper, the adaptive neuroevolutionary autopilot is described and tested on a simulation model of a ferry. Neuroevolution is a combination of two different but related fields of artificial machine learning: evolution and neural networks. The combined method is very flexible and can be applied to other ship control tasks. The results of computer simulation of the neuroevolutionary course-keeping system have been included.
  • Pietrzykowski, Zbigniew; Magaj, Janusz; Wielgosz, Mirosław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Port approaches are high-traffic areas with limited manoeuvring space. Navigation in such areas requires the analysis of large amounts of information, which can impede decision processes. One solution may be the development of decision support systems dedicated to these areas. This paper presents an attempt to build a navigation decision support system operable in the approach area leading to the port of Świnoujście (Poland), with ship domain implemented as a safety criterion. Assumptions for a decision support system to be used by sea-going vessels in port approach areas are formulated and discussed. Specific features of these areas, such as traffic density, bathymetry, available manoeuvring space and legal limitations are taken into account. The source and scope of information available to the ship have been analysed. The scope of decision support has been defined. A ship domain has been proposed as a safety criterion. Approach areas leading to the port of Świnoujście have been investigated on the basis of real Automatic Identification System (AIS) data. Vessel movement processes in the chosen area were analysed. Ship domains in various parts of the area were determined. The first results concerning criteria for navigational safety assessment are presented. The conducted studies showed significant differences in the size of domains. A case study was performed on a decision support system operable in the approach area leading to Świnoujście.
  • Weintrit, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Navigational charts are a basic source of information for seafarers. But how accurate and reliable are they? How much trust and confidence can be put in them? Unfortunately, the answer is not so simple; it is far more complicated than merely saying that one chart is accurate and reliable while another is not. However, any seafarer navigating in unfamiliar waters should have the necessary skills. It is a great challenge – some may say an impossibility – to keep the thousands of navigational charts up to date. But exactly how out of date, how inaccurate, are the chart data? Chart users will have a better idea now that the Hydrographic Office is gradually implementing a new chart feature called the Zone of Confidence (ZOC) box which replaces the Source Diagram that is currently in use on large-scale charts. Source Diagrams, and now the improved ZOCs, assist seafarers in assessing hydrographic survey data and the associated levels of risk of navigating in a particular area. According to the new edition of the International Hydrographic Organization (IHO) specifications, S-4 navigational charts will provide more information on ZOCs. The current paper discusses these new regulations.

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