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This study examines first-year students' perceptions in the English Language Teaching Department at Tishk International University regarding using icebreakers, warmers, and energizers in the classroom. The research aims to assess the effectiveness of these activities in enhancing student engagement and participation, as well as their impact on the overall learning experience. The study contributes valuable insights into the practical applicability of these techniques in an educational setting. Additionally, the positive perceptions of the students underscore the potential of these activities in establishing a favorable and comfortable learning environment. Data were collected through surveys and interviews, employing both quantitative and qualitative methods. For the quantitative aspect, 32 participants (10 males & 22 females) were surveyed, while the qualitative segment involved interviews with 10 students (five males & five females) at Tishk International University. The study's results indicate that the overwhelming majority of students hold a positive perception of the use of these activities. They view them as beneficial for creating a relaxed and comfortable learning atmosphere, fostering interaction and collaboration among classmates, and boosting motivation and interest in the language. The study suggests that incorporating these activities into EFL classrooms can significantly enhance the overall student learning experience and contribute to a more dynamic and interactive classroom environment. The findings are consistent with existing literature in the field. [ABSTRACT FROM AUTHOR]

This article describes five ways in which I have integrated music into law modules as a means by which to engage students: as an icebreaker; to set the tone for a module; to explore questions of representation; to tell stories; and to make theory tangible. The use of music in these ways aims to make students feel differently about the law and to engage their "emotional solidarity". The modules into which music has been interrogated are substantive modules, thus the ideas for practice in this article are therefore ones which are transferable to the teaching of different legal subjects. [ABSTRACT FROM AUTHOR]

Problem statement. The study is aimed to explore how have transformed the traditional approaches of collaborative learning under the influence of new digital environment? And what are the ways of introducing online group activities, precisely icebreakers? Methodology . Authors choose Miro and Mural as the visual platforms for group work activities that enable users to collaborate and customize workspace to better suit their needs. They compared and tested both platforms across six categories: pricing, interface, templates, integrations, customization, collaboration. Results . Authors reach the conclusion that Miro has a significantly larger selection of templates, integrations and apps to choose from. The user interface has a design consistency that ties UI elements together with distinguishable and predictable actions and creates a great user experience overall. Mural offers more facilitation features, which undoubtedly also makes it a powerful tool. But if the price of the tool is also of great importance, Mural might be the right choice. Moreover, there have been considered the approaches of how to organize icebreaker games during the virtual meeting or workshop in Miro and Mural. Authors suggest several exercises: create own character, questions from a bucket, puzzle, world map, five common things, two lies - one truth, take a photo of the desk. Conclusion. Online-whiteboards like Miro and Mural effectively support warm-ups and collaborative visualization in the online environment and allow to achieve higher level of participation than in face-to-face communication.

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Surface atmospheric temperatures over the Arctic Ocean are rising faster than the global average, and sea-ice coverage has declined, making some areas newly accessible to ocean-going ships. Even so, Arctic waters remain hazardous to ships, in part, because of the highly variable nature of sea-ice formation and drift in some areas. In this study, we investigated interannual variability in polar class (PC) ship accessibility in the northern Bering Sea and seas north of the Bering Strait (East Siberian, Chukchi, Beaufort) from February 2012 to February 2022. We used sea-ice charts from the U.S. National Ice Center and calculations of the Risk Index Outcome (RIO) for PC3, PC5, and PC7 ships to characterize spatiotemporal trends in PC ship accessibility during the months of February, June, September, and November over the last 10 to 11 years. We also characterized shipping activity on select days in 2021. Overall, PC ship accessibility during the months of February and June increased over the last decade, especially for PC7 ships. However, areas that became more accessible over time did not support heavy ship traffic, possibly because they were not located on preferred transit routes or because they were surrounded by unnavigable ice, which made them inaccessible in practice. Ship accessibility was highly variable in the northernmost, offshore regions of the study site. During June, PC7 ship accessibility was interannually variable in waters south of the Bering Strait, and ships were active in those regions (most were fishing vessels), indicating potentially hazardous conditions during this time of year. Accessibility was considerably less variable over space and time (months, years) for PC5 (ice capable) ships and for PC3 ships (heavy icebreakers). Information from this study can be used by PC ship operators planning safe and successful shipping routes and by coastal states preparing emergency services to protect the maritime community. As governments and the private sector build out fleets of ice-capable ships, knowledge of interannual variability in ship accessibility will also help planners match PC ship capabilities to mission requirements.

The outbreak of Covid-19 has pushed almost all education-based institutions to migrate their available face-to-face teaching to online teaching. However, online education has posed challenges, especially for learners who are quiet and shy to speak and feeling hard to engage in the course content. At this point, turning Web 2.0 tools into icebreaker activities and incorporating them into online courses could help these students get motivated and develop active participation skills. This study took a selective and theoretical look into the literature about exploring potential Web 2.0 tools and prescribing how to use these tools as e-icebreakers in hybrid or online courses. The findings highlighted many Web 2.0 tools and described how to utilize them in online learning platforms as e-icebreakers. Suggestions about how to design Web 2.0 tool-involved e-icebreakers were provided. The study suggested important implications for instructors striving to keep learners engaged in online or hybrid courses. [ABSTRACT FROM AUTHOR]

This article presents a novel simulation tool for the analysis of winter navigation operations in the Baltic Sea in the context of the Finnish–Swedish Winter Navigation System (FSWNS). The aim of the tool is to simulate the performance of the FSWNS under various potential future operating scenarios and thereby support decision making in matters affecting the operation and development of the FSWNS, for instance, in terms of icebreaking resources and ice class regulations. To this end, the tool considers key performance factors and characteristics of the FSWNS, such as the prevailing ice conditions, the ice-going capability and other technical characteristics of the relevant merchant vessels, the availability of icebreaking resources, and the features of specific icebreaking operations (e.g., convoys). The tool would allow testing of several "what-if" scenarios, answering questions related to optimal engine power for safe, efficient, and environmentally friendly navigation and the optimal scheduling of icebreakers for effective and cost-efficient assistance missions. [ABSTRACT FROM AUTHOR]

This article presents a multi‐part initiative to support diverse learners by building class community and peer networks in an introductory statistics course. This was accomplished through multiple techniques, such as implementing icebreaker questions and using randomly assigned student working groups. The Socrative online software utilized regularly by instructors allowed students to be randomized into groups to collaboratively answer questions provided by the instructors. A multi‐part group project was also administered where students worked cooperatively to analyze swim race data from the 2016 Olympics. Students completed a pre‐semester survey in which they provided feedback on previous mathematics or statistics courses related to the level of course engagement, the benefit of group learning, and their ability to discuss course content during class. A post‐semester survey was administered to answer similar questions regarding the statistics course they were currently taking. [ABSTRACT FROM AUTHOR]

Polar navigation entails challenges that affect the continuation of ship operations in severe ice conditions. Due to ice-propeller interaction, propulsion shafting segments are often at a high risk of failure. Efficient methods for shaft line design are hence needed to ensure the safety of ice-going vessels and propulsion reliability. To this end, full-scale measurements have proven essential to support the development of ship-design tools and updated safety regulations for ice-going vessels. This paper presents a unique integrated measurement system that employs measuring equipment to monitor Polar-Class vessel performance and shaft line dynamics during ice navigation. The system was installed on board the Canadian Coast Guard (CCG) icebreaker Henry Larsen. This experimental concept aims to monitor the shaft's torque and thrust fluctuations during ice navigation to obtain information about the ship's propulsion efficiency. In the paper, we describe the arrangement of the measurement system and the components it features. Finally, we present preliminary datasets acquired during two icebreaking expeditions. This work is framed into a broader research project, which includes the long-term objective to determine a correlation between sea ice conditions and the dynamic response of shaft lines. [ABSTRACT FROM AUTHOR]

Icebreakers have traditionally been seen as symbols of technological nationalism. While ship science for open-water vessels developed during the late nineteenth and early twentieth centuries, understanding of how to cope with polar and subarctic ice conditions lagged behind. This led state organizations in charge of icebreaking services to minimize risks in the development of new vessels by encouraging transnational expert cooperation. This article argues that such interactions were critical to the evolution of the modern icebreaker. We examine the development of three icebreakers in different countries in successive decades, and the critical technologies with which they are associated: the Ymer from Sweden and diesel–electric propulsion (1933); the American 'Wind' class and power-hull proportion (1942–1946); and the Voima from Finland and twin bow propellers (1956). We reconstruct the flow of information to explain the rationale for transnational cooperation in maritime technology development. The concept of 'technology carriers' is deployed in the analysis to enhance understanding of the role of international cooperation in polar and winter seafaring. [ABSTRACT FROM AUTHOR]

A rapidly changing sea-ice regime in the Arctic demands an index that could provide a priori information to icebreakers for hazard-free navigation through ice across the Arctic. This study presents a new sea-ice navigability index, solely based on daily available remote-sensing products. The index has a numerical scale from 0 to 100 that represents the navigability of icebreakers through sea ice. High mobility of sea ice implies that there may be fragmented ice floes that are susceptible to quick displacement, thus allowing an icebreaker to navigate through the ice. [ABSTRACT FROM AUTHOR]

This article presents a novel simulation tool for the analysis of winter navigation operations in the Baltic Sea in the context of the Finnish–Swedish Winter Navigation System (FSWNS). The aim of the tool is to simulate the performance of the FSWNS under various potential future operating scenarios and thereby support decision making in matters affecting the operation and development of the FSWNS, for instance, in terms of icebreaking resources and ice class regulations. To this end, the tool considers key performance factors and characteristics of the FSWNS, such as the prevailing ice conditions, the ice-going capability and other technical characteristics of the relevant merchant vessels, the availability of icebreaking resources, and the features of specific icebreaking operations (e.g., convoys). The tool would allow testing of several “what-if” scenarios, answering questions related to optimal engine power for safe, efficient, and environmentally friendly navigation and the optimal scheduling of icebreakers for effective and cost-efficient assistance missions.

Polar navigation entails challenges that affect the continuation of ship operations in severe ice conditions. Due to ice-propeller interaction, propulsion shafting segments are often at a high risk of failure. Efficient methods for shaft line design are hence needed to ensure the safety of ice-going vessels and propulsion reliability. To this end, full-scale measurements have proven essential to support the development of ship-design tools and updated safety regulations for ice-going vessels. This paper presents a unique integrated measurement system that employs measuring equipment to monitor Polar-Class vessel performance and shaft line dynamics during ice navigation. The system was installed on board the Canadian Coast Guard (CCG) icebreaker Henry Larsen. This experimental concept aims to monitor the shaft’s torque and thrust fluctuations during ice navigation to obtain information about the ship’s propulsion efficiency. In the paper, we describe the arrangement of the measurement system and the components it features. Finally, we present preliminary datasets acquired during two icebreaking expeditions. This work is framed into a broader research project, which includes the long-term objective to determine a correlation between sea ice conditions and the dynamic response of shaft lines.

In level ice, the maneuvering motion of icebreakers has a major influence on the global ice loads of the hull. This study researched the influences of the drift angle and turning radius on the ice loads of the icebreaker Xue Long through a partial numerical method based on the linear superposition theory of ice loads. First, with reference to the Araon model tests performed by the Korea Research Institute of Ships and Ocean Engineering (KRISO), numerical simulations of Araon’s direct motion were carried out at different speeds, and the average deviation between numerical results and model test results was about 13.8%. Meanwhile, the icebreaking process and modes were analyzed and discussed, compared with a model test and a full-scale ship trial. Next, the maneuvering captive motions of oblique and constant radius were simulated to study the characteristics of ice loads under different drift angles and turning radii. Compared with the maneuvering motion model tests in the ice tank of Tianjin University and the Institute for Ocean Technology of the National Research Council of Canada (NRC/IOT), the numerical results had good agreement with the model test results in terms of the variation trend of ice loads and ice–hull interaction, and the influences of drift angle and turning radius on ice resistance and transverse force, which have a certain reference value for sailing performance research and the design of the hull form of icebreaker ships, are discussed.

This article presents a discrete event simulation-based approach for assessing the operating performance of the Finnish–Swedish Winter Navigation System (FSWNS) under different operating scenarios. Different operating scenarios are specified in terms of ice conditions, the volume of maritime traffic, number of icebreakers (IBs), and regulations such as the Energy Efficiency Design Index (EEDI). Considered performance indicators include transport capacity, number of instances of icebreaker (IB) assistance, and IB waiting times. The approach is validated against real-world data on maritime traffic in the Bothnian Bay. In terms of the number of ship arrivals per port, indicating the transport capacity of the FSWNS, the simulation agrees well with the data. In terms of the number of instances of IB assistance and IB waiting times per port, the standard deviations between the mean of 35 independent simulation runs and the data are 13% and 18%, respectively. A sensitivity analysis indicates that the simulated number of instances of IB assistance and IB waiting times is particularly sensitive to assumptions concerning the presence of brash ice channels. Case studies indicate that, unless the number of IBs is increased, the EEDI regulations may result in a significant increase in both the number of instances of IB assistance and the cumulated IB waiting times. [ABSTRACT FROM AUTHOR]

The article contains analysis of nuclear environmental problems of the Arctic region under the International Law. It seems important to further develop cooperation to strengthen the international legal framework for nuclear and environmental security in the region, and to improve the Russian national legislation. Such cooperation should be aimed, inter alia, at creating a regional treaty mechanism for responding to potential nuclear accidents by concluding an appropriate intergovernmental agreement on coordination of cooperation under the Conventions on Early Warning Notification and on Assistance in the Case of a Nuclear Accident or Radiological Emergency. Russia is the only state in the world that owns and operates a civilian nuclear icebreaker’s fleet on the Northern Sea Route. In the coming years the first floating nuclear power plant will start operating in the Chukotka Peninsula. In case of its export abroad, it will be required to create additional international legal instruments. Russia has ratified the 1963 Vienna Convention on Civil Liability for Nuclear Damage but has not yet adopted legislation on its financial implementation. It is required to adopt such a law as well as to accede to the revised 1997 Vienna Convention. Nuclear-ecological problems in connection with the elimination of the “nuclear legacy” of the Cold War are still on top of the agenda. That includes the fate of the radioactive stuffs and waste flooded in the Arctic seas. The main conclusion of the article is that the existing international legal base is ipso facto sufficient for the continued solution of Arctic nuclear ecological problems. Additional focused efforts of all interested Arctic partners are required.

Ice often complicates shipping in extremely cold regions, leading to energy-consuming, expensive transportation. Ship performance can be significantly improved with icebreaking assistance that uses specialized ships called icebreakers to create navigable pathways in ice fields. Icebreakers are a critical and expensive resource with high energy consumption that must be judiciously utilized for efficient traffic flow. Optimizing icebreaker usage requires careful consideration of multiple factors related to weather, ships, and regulations. The existing decision support tools for icebreaker management primarily aim to minimize the total waiting time of ships, which may result in allocation of excess icebreakers. The paper presents a novel simulation-based approach for decarbonizing shipping in ice by intelligent icebreaking assistance. The proposed approach optimizes icebreaker assistance for both eco- and cost efficiency, allowing for more sustainable icebreaking policies. A case study representing a simplified configuration of the Finnish-Swedish Winter Navigation System demonstrates this approach to come up with alternate operating strategies that can significantly improve the emission and/or cost (e.g., up to 7 percent less greenhouse gas emission or up to 14.2% lower costs). Results show that the proposed approach is promising, for providing recommendations on environmental and economic policies to decarbonize the Finnish-Swedish icebreaking assistance. • Shipping in ice requires more energy and resources and incurs higher costs compared to open water. • Icebreaker management improves safety and efficiency of shipping in ice, while responding to climate-related challenges. • A simulation-based decision-making approach incorporates environmental factor in centralized icebreaker assistance management. • Case study in the Baltic Sea demonstrates reduction of CO 2 emission by 7% and cost by 14% than the baseline configuration. [ABSTRACT FROM AUTHOR]

The author analyzed the trends and prospects of the Northern Sea Route. The main problem is that this rather complex system is influenced by many factors, often contradictory and poorly predicta-ble. Thus, the increase in demand for energy and resources determines the overall need for the development of the Arctic shelf. However, the possible cooling and worsening of the ice conditions may adjust to the possibility of transporting of the resources to the Asia-Pacific market, for instance. In this regard, along with the methods of factor and economic analysis the expert approach was used for the study. Its main result is a package of proposals aimed at supporting the Arctic marine cargo flow.

This article presents a discrete event simulation-based approach for assessing the operating performance of the Finnish–Swedish Winter Navigation System (FSWNS) under different operating scenarios. Different operating scenarios are specified in terms of ice conditions, the volume of maritime traffic, number of icebreakers (IBs), and regulations such as the Energy Efficiency Design Index (EEDI). Considered performance indicators include transport capacity, number of instances of icebreaker (IB) assistance, and IB waiting times. The approach is validated against real-world data on maritime traffic in the Bothnian Bay. In terms of the number of ship arrivals per port, indicating the transport capacity of the FSWNS, the simulation agrees well with the data. In terms of the number of instances of IB assistance and IB waiting times per port, the standard deviations between the mean of 35 independent simulation runs and the data are 13% and 18%, respectively. A sensitivity analysis indicates that the simulated number of instances of IB assistance and IB waiting times is particularly sensitive to assumptions concerning the presence of brash ice channels. Case studies indicate that, unless the number of IBs is increased, the EEDI regulations may result in a significant increase in both the number of instances of IB assistance and the cumulated IB waiting times.

The article analyzes the trends and evaluates the prospects of functioning of the Northern Sea Route. It shows that after the change of its management model its freight traffic has dropped 4-fold, and in the Eastern sector (outside the Vilkitsky Strait) – 40-fold. In the recent years there has been a certain revival of transportation, including transit, which reached its maximum of 1.27 million tons in 2012. However, over the next two years they declined again; the drop was particularly significant in 2014 and amounted to a total of 240 thousand tons. The main problem is that this rather complex system is influenced by many factors, often contradictory and poorly predictable. Thus, the growing need for energy resources determines the overall need for developing the Arctic shelf. However, the possibility of climate cooling and the deterioration of ice situation can influence the possibility of transporting these resources. Besides, the Ukrainian crisis followed by the “war of sanctions” will cause a significant decline, especially in the medium term, the attractiveness of the European oil and gas market, which will cause the shift of strategic interests of Russian companies to the Asia-Pacific region. This necessitates the modernization of the Arctic transport and logistics system and introduction of new technical solutions. For instance, even nuclearpowered icebreakers series LA-60Ya that are currently under construction will not be able to escort linear tankers and gas carriers with a deadweight of more than 100 thousand tons along the eastern sector of the Northern Sea Route. It is necessary to create more powerful vessels of the classical type or to design new models. All these driving forces and constraints are not always predictable within the framework of standard economic and statistical approaches. In this regard, the study reflected in the article used expert approaches along with the methods of factor and economic analysis. The main result is a package of proposals for the support of the Arctic marine freight traffic

The article deals with the modern processes of formation and development of the marine transportation system in the Russian Arctic, analyzes its problem areas and reserves growth. Shows the status and prospects of development of cargo specialized fl eet of ice-class and icebreakers. Particular attention is paid to infrastructure, port management, port The possibility of creating special economic zones. Systematized direction of modernization of the Arctic marine transportation system.

The starting point of the analysis in hand is a brief discussion of the so-called ‘Arctic Passages.’ Considering that ice and ice-pacts will remain a concern in the future, the support of icebreakers will still be needed to facilitate the safe passage of ships. Describing the state of these types of vessels currently available is the main aim, with a particular focus on key state players: the Russian Federation (RF), the United States of America (USA) and Canada. Additionally, a critical evaluation of future plans in relation to the introduction of icebreakers into service is taking place. Russia has already built and operates a certain number of vessels that are fully capable to handle current traffic demands, as well as the expected future increase. On the opposite direction, both Canada and USA are facing problems to deal with current demands and the situation during the next couple of years looks rather troublesome. Their obvious lack of icebreaking capabilities is somewhat disconcerting given the expected demand in the Arctic region in coming years coupled with the lengthy acquisition and production process required for a new icebreaking fleet. An acceleration of their acquisition plans and activities to cover the identified gap in icebreakers’ services is clearly a high priority. [ABSTRACT FROM AUTHOR]

The steady operation of the Northern Sea Route is based on large icebreakers, which ensure access to various Russian regions through the navigable Arctic. Some nuclear-powered icebreakers built as far back as the Soviet era need to be replaced. Up to now, it hasn’t been clear how the icebreaker fleet will be used to make the Northern Sea Route operate more efficiently. It is also not clear whether Russia’s authorities will permit independent navigation by commercial icebreaking carriers without convoys escorted by icebreakers. [ABSTRACT FROM AUTHOR]

Stress on the environment from a potentially growing energy use is set to rise. Without doubt the energy resources in Arctic regions will be developed. An important goal will be to exploit the resources offered by for instance the Barents Sea as a new European energy province, and to do this in accordance with the principles of sustainable development that have successfully been used e.g. in the North Sea. The special edition of MIC on Arctic DP presents a set of articles that summarize to an extent the activities of the research project Arctic DP: Safe and green dynamic positioning operations of offshore vessels in an Arctic environment. This project was awarded in 2010 by the Research Council of Norway (RCN) as a competence-building project (KMB project) to NTNU and its partners Kongsberg Maritime, DNV GL, and Statoil. The objective was to target some of the challenges related to safe Arctic offshore operations by dynamic positioning. In this first article of the Arctic DP special edition we discuss the background for and establishment of the project, its planning and execution, and project closure. An overview is given for the scientific and engineering research performed in the project, with an account of what we have considered as Effective stationkeeping in ice by dynamic positioning. The corresponding research activities conducted under this main theme is summarized.

Finland is the only country in the world where all ports freeze over during a typical winter. Over the century 1878–1978, Finland developed a winter-seafaring system that broke the winter isolation and eliminated seasonal variation in shipping. By using diverse archival sources, we deconstruct the dominant narrative of Finnish winter seafaring through which national as well as technological development is often presented as natural, inevitable and straightforward. We reinterpret the Finnish winter navigation system as a tangible, historical experience and show that technological solutions in this domain cannot be understood outside the context of a decades-long process of nation-building. Finally, we argue that winter navigation became a central imaginary for Finland as a western, industrial and modern nation. As such, the Finnish winter-seafaring system presents a case of technological nationalism in which a small, peripheral country sought to integrate itself into a modern international order. [ABSTRACT FROM PUBLISHER]

The USSR and now Russia have employed a fleet of large icebreakers to gain access across the Russian maritime Arctic and facilitate traffic through the Northern Sea Route ( NSR). Since 2008, Atomflot has played a very influential role, not only in the management and operation of Russia's icebreakers, but in laying premises for the NSR as a whole. The current NSR Administration within the Ministry of Transport does not appear to have roles in policy formation, icebreaker management, or planning. Several of the Soviet-era nuclear-powered icebreakers are in need of replacement, but the construction program for new ships is marked by controversies. There is no integrated management of nuclear and conventional icebreakers, and it is unclear how the icebreaker fleet will be used to enhance the effectiveness of NSR operations, and also to what extent the authorities will allow the independent navigation of icebreaking commercial carriers without convoy escort by icebreakers. [ABSTRACT FROM AUTHOR]

During navigation in Polar regions, ice-induced torque excitation endangers the operation and integrity of ship propulsion systems. Predicting these dynamic phenomena through proper numerical models is therefore essential. This paper studies the influence of different properties of the ice–propeller torque on the transient torsional dynamics of a Polar-Class shafting system. We initially considered the ice torque defined by the current regulatory framework. Hence, we examined variants of four ice impact properties—(i) rise shape; (ii) angular span; (iii) ramps up–down feature; (iv) number of ice impacts—to study the transient and steady-state conditions induced by the ice–propeller excitation. We performed a series of torsional vibration analyses using the numerical model of the shaftline of the Canadian Coast Guard (CCG) icebreaker Terry Fox. Furthermore, we tested the system with Diesel engine and electric motor excitation models interchangeably; the electric drive solution proved to counter ice-induced transient perturbations more effectively. The results indicate that the ice impact span, the ramps up–down application, and the number of impacts are the most important factors to affect the shaftline's rotational speed drop and response torque. In particular, the significance of the ice impact ramps is such that it might entail a review of the in-force regulatory guidelines. • Multi-factor modifications of the Polar Rules' ice–propeller torque are implemented to study their effects on shaft vibrations. • Diesel and Electric drives are simulated as alternative design solutions to test their capability in countering ice-induced perturbations. • Ice–propeller torque excitation with low-number consecutive pulses may cause severe torsional vibration responses along shaftlines. [ABSTRACT FROM AUTHOR]

Electric propulsion has emerged as one of the most efficient propulsion arrangements for several vessel types over the last decades. Even though examples can be found in the history at the end of 19th century, and further into the 20th century, the modern use of electric propulsion started in the 1980s along with the development of semiconductor switching devices to be used in high power drives (dc drives and later ac-to-ac drives). This development opened up for full rpm control of propellers and thrusters, and thereby enabling a simplification of the mechanical structure. However, the main reason for using electric propulsion in commercial ship applications is the potential for fuel savings compared to equivalent mechanical alternatives, except for icebreakers where the performance of an electric powered propeller is superior to a combustion engine powered propeller. The fuel saving potential lies within the fact that the applicable vessels have a highly varying operation profile and are seldom run at full power. This favors the power plant principle in which electric power can be produced at any time with optimum running of prime movers, e.g., diesel engines, by turning on and off units depending on the power demand for propulsion and other vessel loads. Icebreakers were among the first vessels to take advantage of this technology later followed by cruise vessel, and the offshore drilling vessels operating with dynamic positioning (DP). The converter technology was rapidly developing and soon the dc drives were replaced with ac drives. In the same period electric propulsion emerged as basic standard for large cruise liners, and DP operated drilling vessels, but also found its way into other segments as shuttle tankers, ferries, and other special vessels. At the same time podded propulsion were introduced, where the electric motor was mounted directly on the propeller shaft in a submerged 360 ^\circ steerable pod, adding better efficiency, improved maneuvering, and reduced installation space/cost to the benefits of electric propulsion. The future trends are now focusing on further optimization of efficiency by allowing multiple energy sources, independent operation of individual power producers, and energy storage for various applications, such as power back up, peak shaving, or emission free operation (short voyages). [ABSTRACT FROM PUBLISHER]

The paper discusses the application of high-power lasers to break the ice cover cover (up to several meters in height) around such engineering structures as oil platforms and icebreakers. The most effective in this case is the joint application of high-power lasers and icebreakers in the cracking of ice covering the ocean. The most dangerous hazards resulting from drifting ice can be easily overcome with the help of high-power lasers. It is obvious today that lasers on offshore oil and gas platforms in the Far North will be in high demand and can greatly facilitate the safety of the personnel of such rigs [ABSTRACT FROM AUTHOR]