Dépôts récents

  • Programming of marine engineers' simulator training

    Savateev, D. A. (2022-12-22)
    Vestnik of MSTU
    Continuous improvement of the technical equipment of sea vessels is inevitably accompanied by the development and complication of the training base for marine specialists. Simulator training based on a computer model of operating the units of the liquefied natural gas tanker of the Veliky Novgorod type includes interactive computer programs for learning management, created using the e-Tutor computer module included in the simulator delivery set. In the course of systematizing the experience of using specialized programming tools for educational and research activities of students in organizing and conducting simulator training for electrical engineers on computer simulation models of sea vessels, a system of conventional graphic symbols for the elements of the flowchart of the training exercise program has been formed and their description has been given. Training and control exercises include familiarization with the mnemonic diagrams of the integrated marine vessel automation system and assessment of the state of the ship's electrical power system with their help, starting the propulsion electrical installation, providing energy to the operating propulsion electrical installation under load changes, switching on the backup diesel generator unit for parallel operation with the network in normal and emergency modes, acceleration of the vessel to the given speed in accordance with the tasks of the instructor. The advantages of training programming using the e-Tutor computer module are the ability to use the simulator in self-study mode with automated teaching support.
  • Features of ensuring high-quality work of modern electrical power systems of unmanned vessels

    Savenko, A. E.; Savenko, P. S. (2022-12-22)
    Vestnik of MSTU
    Unmanned seagoing vessels are increasingly being used. In the paper the dump scow Rabochaya is considered as an example of an unmanned vessel. An extended marine control system, a video surveillance subsystem, a surveillance and search engine are additionally installed on the scow to carry out industrial tasks in unmanned mode. The correct operation of these systems and the whole vessel depends on the high-quality operation of the ship's electrical power system. The aim of the study is to identify abnormal modes of parallel operation of marine diesel generator sets and to develop methods and means for their elimination. The results of the experimental research and mathematical modeling have revealed the existence of power exchange oscillations when the ship generators operating in parallel. Power exchange oscillations can be detected with the help of generator current oscillations. It has been proposed to introduce a unit for eliminating power exchange oscillations (EPEO) into the automatic control system of ship electrical power systems for eliminating such oscillations. An algorithm for the operation of the EPEO unit has been developed, it controls the settings of the rotational speed regulators of diesel-generator sets. The proposed methods and tools reduce the amplitude of power exchange oscillations to an acceptable value, and therefore contribute to the high-quality operation of the ship's electrical power system and control systems in unmanned mode. The results obtained make it possible to ensure reliable and trouble-free operation of any autonomous electrical power system during the operation mode without maintenance personnel.
  • Application of the proportional navigation method in solving problems of navigation

    Solovyov, A. A.; Shugay, S. N. (2022-12-22)
    Vestnik of MSTU
    The development of methods and algorithms for ship control when maneuvering relative to a moving object and the creation of automated control systems based on these developments is an urgent task of navigation. The most optimal way to implement control of a moving object relative to another moving object is based on using the proportional navigation method. As applied to navigation problems, this method has been studied at the level of describing the kinematics of the movement of two points. The mathematical model provides for a preliminary calculation of the extrapolated ship coordinates. The construction of ship motion trajectories for any given proportionality factor is carried out taking into account the dynamics of the ship and makes it possible to obtain the law of rudder shift, as well as to predict changes in the process of maneuvering such ship parameters as angular velocity and drift angle. The proposed mathematical model can be used for algorithmic and software support for automated ship control systems when maneuvering relative to a moving object.
  • Assessment and fishery of shellfish stocks in the Barents and White Seas in 2000–2020

    Bakanev, S. V.; Matyshkin, V. B.; Sennikov, A. M.; Stesko, A. V. (2022)
    Vestnik of MSTU
    Hydrobionts have a high nutritional value and are the most important component of the food supply for the population of Russia. In the course of the study, the characteristics of the stocks and fisheries of the king crab, opilio snow crab, northern shrimp, Icelandic scallop, sea green urchin and other commercial invertebrates in 2000–2020 are presented. The raw material base of the fishery of the king crab and snow crab is used in full; the indices of their commercial biomass are 215 and 430 thousand tons, respectively; development of TAC – more than 90 %. While maintaining the current management strategy, their commercial stocks will be at a stable level or increase. The commercial stock of the northern shrimp in the Barents Sea and adjacent waters is in a satisfactory condition (at the end of 2020 it was estimated at 2.2 million tons); the distribution density of shrimp in the Russian EEZ has halved. The resource base of the Icelandic scallop fishery in the Barents Sea is not exploited due to the depressive state of the stock: the median of commercial biomass is at the level of 200 thousand tons, which is below the boundary biomass target (224 thousand tons). The growth in the catch of the sea urchin is due to the increased interest of fishers in this object. The annual catch of the sea urchin does not exceed 10 % of the recommended one, fishing efforts are unevenly distributed over different parts of the Murman coast. Cucumaria, mussel, trumpeter, shrimp bear cub, clema, euphausiids are caught in small quantities and remain in the category of underutilized fishery objects.
  • Investigation of the effect of structure-regulating additives on the properties of minced fish systems

    Bogdanov, V. D.; Simdyankin, A. A.; Pankina, A. V.; Mostovoy, V. D. (2022)
    Vestnik of MSTU
    The search for new effective structure-forming agents of natural origin in order to improve the technology of fish molded products is an urgent scientific and industrial problem. In the course of the study, to obtain minced fish systems, frozen pollock and pink salmon have been used that meet the technical requirements of the current regulatory documentation. Mixtures of cryoconcentrates from seafood, rice and wheat flour, and the enzyme transglutaminase are used as structure-regulating additives. Cryoconcentrates have been made from cucumaria, squid, Pacific herring milt, octopus skin, seaweed, and scallop mantle. The introduction of dry powdered cryoconcentrates of seafood, containing a significant amount of protein substances, has contributed to the binding of water and an increase in the water-retaining capacity of minced pink salmon and pollock. Based on the results of studying the physical, chemical, rheological and organoleptic properties of dispersed minced fish systems, rational amounts of structure-regulating additives have been established: seafood cryoconcentrates – 4.0–5.0 %; transglutaminase – 0.5 %; rice flour – 2.0 %; wheat flour – 1.0–2.0 %. Molded fish products (cutlets, sausages) containing structure-regulating additives had high organoleptic properties after heat treatment. The results of the research should be used in the development of formulations of fish dispersed compositions in the technologies of molded, emulsion and structured products. The established high water-binding capacity of seafood cryoconcentrates justifies the need to study them as natural cryoprotectors in refrigeration technologies.
  • Analysis of complex changes in salmon salting by injection using the food additive PRE-LACKS

    Lukina, E. V.; Shokina, Y. V.; Antonov, P. V.; Levshina, I-E. O. (2022)
    Vestnik of MSTU
    The paper presents the results of a comprehensive assessment of the quality of delicacy fish products – salmon fillets of weak salt made using the food additive PRE-LACKS (LLC "Vash technologist", St. Petersburg, Russia) and curing by injection. For the first time, the influence of technological factors has been studied (the concentration of a food additive (in the range recommended by the manufacturer from 3 to 5 % with a step of 1 %), as well as the value of the hydromodulus (in the range from 5 to 20 % with a step of 5 %) characterizing the ratio of masses of the fillet introduced into the thickness when injecting brine and a salted fillet piece) on the formation of a complex indicator of the finished product quality. The developed scale for a comprehensive assessment of the quality (K) of lightly salted salmon fillet of injection salting is presented, including the main groups of indicators – organoleptic and rheological, nutritional value and physico-chemical. The scale includes weighting coefficients based on the results of experimental and sensory studies – both group and for each quality indicator taken into account. It has been shown that using the fuzzy logic method made it possible to obtain the values of the selected influencing factors optimized according to the criterion of achieving the maximum value of K (in the range from 0.9 to 1.0 conventional units, corresponding to the category "delicacy product") – the concentration of the food additive and the value of the hydromodulus – 4 and 15 %, respectively. The results of assessing the influence of selected technological factors on the yield of a semi-finished product immediately after salting by injection, on the yield of finished low-salted products (after ripening), on indicators characterizing the completeness of its maturation (buffering, the ratio of the mass fraction of non-protein nitrogen to the mass fraction of total nitrogen, total acidity, mass fraction of amine nitrogen) have been presented. Based on the results of the research, technological recommendations are formulated for salting salmon by injection using the PRE-LACKS food additive to increase the yield of finished products and improve its consumer properties.
  • The role of rotifer in water quality improvement in a fishpond

    Gerasimova, T. N. (2022)
    Vestnik of MSTU
    Rotifers are common in fresh and brackish water bodies, in coastal areas of the seas, and can be an effective tool for analyzing the state of the environment. The ability of rotifers to adapt to unfavourable environmental conditions has been considered in the course of studying the species composition of rotifers in a fish pond near Moscow under the conditions of the supply of organic artificial food for fish and changes in the temperature regime of water. During the period of increased temperature of the water (21–25 °C) and decrease in the concentration of dissolved oxygen from the surface to the bottom layers of water from 3.8 to 0.2 mgO2/L in early July, Asplanchna priodonta helvetica, Brachionus angularis angularis and Brachionus calyciflorus dominated in the pond (98–100 % of the abundance and 99–100 % of the biomass of rotifers). During the period of elevated temperatures, the turbidity indices in the upper layer (0.2–0.5 m) were an order of magnitude lower than those in the deeper layers of the reservoir. Bacteria and tiny particles served as food for rotifers. The temperature of 18–25 °C was favourable for the development of B. angularis angularis in the fish pond. At a temperature of 18 °C, its abundance reached 1,500 ind./L (70 % of the abundance of rotifers). In August, when the temperature of the water column decreased from 20 to 18 °C, the biomass of A. priodonta helvetica changed from 0.3 to 9.5 mg/L (99 % of the biomass of rotifers). Polyarthra vulgaris dominated among small rotifers. During the period of low temperatures, the biomass of rotifers increased to 20 mg/L; its basis was A. priodonta helvetica. Rotifers are able to adapt to conditions of high organic input in a wide range of temperatures and participate in the restoration of water quality in a fish pond.
  • Bycatch of marine mammals in the Northwest Atlantic during commercial fishery (based on literature materials and observations by the Polar branch of VNIRO in 2013–2020)

    Mishin, Т. V. (2022)
    Vestnik of MSTU
    This paper describes one of the most acute problem for both environmental companies and fisheries – bycatch of marine mammals caused by bioresource exploitation in the Northwest Atlantic (NWA). There is no doubt that fishing has some impact on marine mammals, but information on bycatch of marine mammals is needed to understand the extent of the impact of different fishing gears. The paper is based on data from reports of observers of the Polar branch of VNIRO from fishing vessels in the 3LMNO NAFO zone (Newfoundland Island), as well as literary materials. As a result of the analysis, it has been found that small species of marine mammals, such as gray, common, harp seals from the Phocidae family, common dolphin, short-finned pilot whale (Delphinidae family) as well as harbour porpoise from the Phocoenidae family are most often injured by various fishing gears. Toothed whales (sperm whale, bottlenose whale) are the least susceptible to bycatch. Among the baleen whales, humpback whale, northern right whale and minke whale are often the victims of fishing. Gillnets, trawl fishing, and longlines are the greatest threats to small marine mammal species, while baleen whales are most vulnerable to traps, usually to catch ten-legged crustaceans Decapoda. Analysis of the literature has shown that, in general, the stocks of most marine mammal species in the NWA, excluding the northern right whale, are in a stable condition. The manuscript considers measures aimed at reducing bycatch of marine mammals.
  • Changes in the smoltification age of Atlantic salmon (Salmo salar L.) of the Yokanga, Kharlovka and Vostochnaya Litsa Rivers (the Murmansk Region)

    Dolotov, S. I.; Kuzmin, D. O. (2022)
    Vestnik of MSTU
    Throughout the world, in recent decades, there has been a decrease in the abundance of Atlantic salmon, the main reason for which is a decrease in its survival rate during life at sea. Its value has a direct dependence on the length and, accordingly, the age of the smolts. Foreign researchers have found that the nature of long-term changes in the age structure of smolts can vary significantly by region. At the same time, the age of Atlantic salmon in Russian rivers, which account for a significant part of the area of the range of this species, was not considered. In this regard, the analysis of long-term data characterizing the age composition of salmon smolts of some rivers of the Murmansk region has been carried out. It has found been that in the first years of the period 2000–2018, the age structure of Atlantic salmon smolts was transformed in the rivers Yokanga, Kharlovka and Vostochnaya Litsa. As a result, fish at the age of 6 ceased to occur among them, the abundance of fish at the age of 5+ significantly decreased and the abundance of fish in the age groups of 3+ or 4+ significantly increased. The most likely reason for this is the change in the temperature regime of rivers since the mid-1990s, as a result of which the life time in the rivers of juvenile salmon has been reduced. Rejuvenation of the smolt population may have ambiguous consequences for the abundance of adult salmon, which are determined by the cumulative effect of reducing natural mortality at the stage from eggs to smolts, increasing their abundance and reducing their length, and reducing the survival rate during salmon life in the sea.
  • Polychaeta fauna in the northeastern Barents Sea

    Dikaeva, D. R. (2022)
    Vestnik of MSTU
    The northeast of the Barents Sea (the area between the Franz Josef Land and Novaya Zemlya archipelagos) is one of the little-studied areas characterized by a complex structure of the hydrological regime, bottom relief and bottom sediment structure. This area is characterized by the predominance of brown soils with a large number of foraminifera shells, which affects the species composition and structure of benthic communities. The species composition and quantitative characteristics of polychaetes in the northeastern part of the Barents Sea were analyzed on the basis of material collected in December 2019 during Murmansk Marine Biological Iinstitution expeditions on the r/v Dalnie Zelentsy. Faunal complexes of polychaetes have been identified in the study area depending on environmental conditions (type of bottom sediments, depth, hydrological conditions). In the areas of marginal troughs, the detritophagus Spiochaetopterus typicus dominates in terms of biomass and abundance, forming abundant settlements on soft silty-sandy, silty-clay soils. Low values of biomass and abundance have been noted on brown silts with a large number of foraminifera, dominated by Laonice cirrata. On the slopes of underwater hills, washed more strongly by bottom currents, on rough sandy soils with low nutrient content, the dominance of Nephtys ciliata has been noted. The species Sphaerodoridium kolchaki sp. n. recently encountered in the Barents Sea has been noted in the study area as well. The obtained data complement information on the species composition of the northeastern part of the Barents Sea and make it possible to trace further changes in the composition and structure of benthic communities.
  • About terraces on the shore of the Teriberskaya Bay of the Barents Sea (the Kola Peninsula)

    Neradovsky, Yu. N.; Miroshnikova, Ya. A.; Companchenko, A. A.; Chernyavsky, A. V. (2022)
    Vestnik of MSTU
    The paper considers the results of the study of modern terraces on the coast of the Lodeyny Peninsula in the Barents Sea. According to field observations, decoding of space and geodetic maps and volumetric modeling, signs of three terraces have been identified. Two terraces having a rear seam, a cliff, a brow and horizontal platforms have been studied in more detail. The rear seams are located at 7 and 30 m, and the edges at 10 and 40 m above the sea level. The third terrace is confined to the level of 40–60 m, and has not been studied in detail. According to estimates, the first two terraces were formed about 3,300 and 6,000 years ago respectively. The 1st terrace characterizes the period of slow land rise by 10 m, at the speed up to 3 mm/year, which began about 3,300 years ago and continues to the present. It is characterized by a uniform sea retreat of about 15 mm/year. The erosion products of this terrace are common in the lateral zone and represent modern marine sediments, including beaches forming a new terrace. The 2nd terrace characterizes to the dynamics of rapid land rise by 30 m at a speed of about 11 mm/year, which occurred in the period from 6,000 to 3,300 years ago. The erosion products of this terrace are most common on the coast and are found at a distance of 100 m to 2–3 km from the shore. It is assumed that the speed of movement of the coastline during the retreat of the sea was different and reached up to 900 mm/year. According to the authors, preliminary data indicate the instability of the territory and the manifestation of block movements, which may have a negative impact on the development of infrastructure.