Статьи журнала - Вестник Мурманского государственного технического университета
Все статьи: 2131
High-latitude version of the global numerical model of the earth's upper atmosphere
Статья научная
The global numerical model describing the thermosphere, ionosphere and protonosphere of the Earth as a single system has been modified for the polar upper atmosphere studies. The spatial and time resolution of the model has been significantly enhanced by the use of the variable latitudinal steps of numerical integration. The model is being developed to encompass modelling of the inner part of the magnetosphere confined by the closed geomagnetic field lines and the mesosphere. The results of the model calculations for the quiet magnetic conditions have been compared with the data of the empirical ionospheric and thermospheric models as well as with the EISCAT data and, in general, reasonable agreement between theoretical and empirical data has been found. The new high-latitude version of the model has been applied as well to the investigations of the disturbed behaviour of the Earth's upper atmosphere during geomagnetic substorms and storms and during disturbances in the cusp region. The physical mechanisms of the upper atmosphere responses to the solar wind and magnetospheric forcings have been understood by the use of the model in several case studies.
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Статья научная
The GPS derived TEC disturbances before earthquakes were discovered in the last years using global and regional TEC maps, TEC measurements over individual stations as well as measurements along individual GPS satellite passes. For strong mid-latitudinal earthquakes the seismo-ionospheric anomalies look like local TEC enhancements or decreases located in the vicinity of the forthcoming earthquake epicenter. Such structures are generated in the ionosphere for several days prior to the main shock. The amplitude of plasma modification reaches the value of 30-90 % relative to the non-disturbed level. The zone of the anomaly maximum manifestation extends larger than 1500 km in latitude and 3500-4000 km in longitude. In case of strong low-latitudinal earthquakes there are effects related with the modification of the equatorial F2-region anomaly: deepening or filling of the ionospheric electron density trough over the magnetic equator. The possible physical mechanism which can cause such anomalies has been proposed. We consider that the most probable reason of the NmF2 and TEC disturbances observed before the earthquakes is the vertical drift of the F2-region ionospheric plasma under the influence of the zonal electric field of seismic origin. To check this hypothesis, the model calculations have been carried out with the use of the UAM (Upper Atmosphere Model) -the global numerical model of the Earth's upper atmosphere. The electric potential distribution at the near-epicenter region boundary required for the electric field maintenance has been proposed. The upper atmosphere state, presumably foregone a strong earthquake, has been modeled by means of switching-on of additional sources of the electric field in the UAM electric potential equation which was solved numerically jointly with all other UAM equations (continuity, momentum and heat balance) for neutral and ionized gases. The efficiency of the proposed mechanism has been investigated by means of model calculations of the ionosphere response to the action of zonal electric field produced by seismogenic sources located at the middle and low latitudes. The results of the corresponding numerical model calculations of the electric field and its effects in the ionospheric F2-layer and plasmasphere have been presented. They have revealed a fine agreement with TEC anomalies observed before strong earthquakes at the middle and low latitudes both in spatial scales and in amplitude characteristics.
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Статья научная
The numerical global Upper Atmosphere Model (UAM) has been used for studying the lower thermosphere and ionosphere behaviour during a strong magnetic storm of March 31, 2001. A comparison of the calculation results with the Millstone Hill IS radar data obtained during this magnetic storm has been carried out. A satisfactory agreement between the measured and calculated ion temperatures, electron and ion drift velocities has been obtained. The calculated electric field variation is similar to the observed one but is twice less in magnitude. As to the neutral horizontal wind velocities, there is a large difference between the calculated values and data obtained by the Millstone Hill IS radar, down to the different signs of the wind components. This difference can be bound up to distinctions in the frequencies of the ion-neutral collisions dependent on the neutral atmosphere parameters and the ion composition, and in the electric fields measured at Millstone Hill and theoretically calculated by the UAM. The reasons of the discrepancy of the thermospheric winds simulated by the UAM and calculated at Millstone Hill have been examined. The results of this examination show that the Millstone Hill wind results are very sensitive to the measured electric field values especially when the last are so large as they were in the case, and therefore even a moderate difference between the calculated and observed electric fields may cause a significant discrepancy of the thermospheric winds simulated by the UAM and calculated at Millstone Hill.
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Method for determining the quality of cable inlets sealant using infrared thermography
Статья научная
He results of applying the quality control method to cable inlets sealant (hermetic lead, sealed lead-in, cable boxes) have been considered. Cable inlets are designed to prevent the spread of fire in adjacent areas through cable sealing boxes, e. g. on sea vessels. The known methods for determining the quality of cable inlets sealant are laborious and in some cases even impossible to implement when used on sea vessels. This applies to cases when the room through which the cables pass is being poured with water and some pressure stipulated by the ship specifications is being created there, or when the air pressure increases in such rooms. The novelty of the present method lies in the fact that it is based on the principles of pulsed thermal non-destructive testing of a material. The FLUKE thermovision camera Ti400 has been used as a technical means recording the temperature field of the sealant surface after exposure to a thermal pulse. The method approbation has indicated that thermal non-destructive testing can be used to detect relatively small penetration defects in the sealant volume.
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Modelling cyclic reverse movements of the vessel using modified Lammeren's curves of screw action
Статья научная
In our national practice, the screw action curves are traditionally used either for positive values of the screw speed n and the vessel's velocity v, or when one of these characteristics of the movement is negative. Consequently, the used curves of the screw action do not allow to create computer simulators for testing specific maneuvering tasks with reversible moves. The purpose of the work is to study the opportunities of mathematical modelling of the vessel's reverse movements, when the propeller advance of the fixed pitch screw is constantly changing. In foreign sources, really universal Lammeren's curves of screw action can be found. The specificity of these curves is that the introduction to them is performed not due to the pitch ratio itself, but due to the angle b of the direction incident to the propeller blade. This angle is determined by using tangent tg(b) = v /(0.7 π nD ), and it is sensitive to the change of sign of both the ship's velocity v and the revolution speed n...
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Статья научная
Мусковит-микроклиновые метасоматиты по гнейсам архейского комплекса Кольской сверхглубокой скважины обнаружены в нижней части разреза, вскрытого третьим стволом СГ-3 в интервале глубин 12172-12235 м, и по особенностям геологического положения, составу и возрасту (2225±5 млн. лет) коррелируются с гранитоподобными породами формации приразломных метасоматитов, занимающих площадь не менее 300 км2 в архейских породах северного обрамления Печенгской рифтогенной структуры. Образование метасоматитов происходило в условиях повышенного потенциала CO2, P, F, B и сопровождалось увеличением в гнейсах субстрата содержания как элементов сидерофильной (Fe, Ti, Cu, Ni, Co, Cr, V), так и литофильной (K, Rb, Ba, Nb, Zr, Y, TR, Pb, Th) групп. Указанные особенности состава свойственны для субщелочных пород раннеорогенной трахибазальтовой (муджиерит-трахитовой) формации (2214±54 млн. лет), породы которой имеют мантийный генезис и, как предполагается, были источником богатых углекислотой флюидов, производивших метасоматическую переработку гнейсов в зонах глубинных нарушений. По Pb-изотопным данным, свинец в метасоматитах был образован при смешивании привнесенного флюидами мантийного свинца со свинцом из гнейсового субстрата с возрастом 2.8 млрд. лет. Более радиогенный изотопный состав Pb некоторых плагиоклазов, отвечающий свинцу верхнекоровых образований, не противоречит предположению о перестройке Pb-Pb систем полевых шпатов из мусковит-микроклиновых метасоматитов в процессе внедрения анатектических тел свекофеннских гранитов с возрастом 1765±2 млн. лет. Исследования были инициированы В. Ветриным при работе по русско-норвежскому проекту Северный район в 1990-1993 гг. и являются вкладом в проект IGCP-408.
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Object-oriented hierarchical data structure for framework atmospheric model
Статья научная
A universal modeling tool is being developed on the basis of the global Upper Atmosphere Model (UAM) for studying the interrelationship of the broad range of various processes and phenomena in the upper atmosphere. For this purpose the UAM structure was reorganized into the open framework, including the controlling Metamodel Manager and several subordinate models of separate atmospheric regions and processes. They are, for example, an ionosphere model, neutral atmosphere model, electric field model, wind model etc. Each included model is independent from the others and calculates the certain set of physical parameters of the modeling object. These sub-models exchange data through the Manager using the unified interface. This approach allows the integration of a wide range of data sources of different kinds, both experimental and modeled. This work contains a detailed description of model data internal logical organization, which provides the possibility to store and to exchange various kinds of data with a full description in a standardized way
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Pieces of evolution's puzzle: a social-philosophical perspective
Статья научная
This paper tries to show that evolution is an outdated theory in human-social sciences; it has been applied in the past and is now set to become obsolete. This is because human agency, free-will, decision-making and intentionality are predominantly excluded from social-humanitarian evolutionary discourse, which leads to a dehumanizing effect. An updated, non-evolutionary (cf. post-evolutionary) view of human-social change(s) that suits the information-electronic age and ushers in a teleological perspective would offer a timely solution to this problem.
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Qualitative visualization of the development of stresses through infrared thermography
Статья
In this work, the IR thermography has been used to study the steel specimens (DIN 50125 Standard) undergoing the tensile tests. The tensile tests were performed using GUNT® Hamburg Universal Material Tester. The tensile specimens were clamped, and the test force was applied using a hand-operated hydraulic system. A dial gauge measured the elongation of the specimens. The steel specimens were coated with high emissivity paint. Using the WP 300.20 system for data acquisition, the measured values for force and displacement were recorded in a PC. The IR thermographic imaging was performed using the FLIR® T1030sc IR camera and ResearchIR Max software. The tests have revealed that the steel specimens show noticeable thermal signature when undergoing tensile loading.
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Quality assurance in education
Статья научная
Quality Control and Quality Assurance principles were introduced in manufacturing industry as early as in the 1940 - 50's, and have since been developed to include all activities in any business. In the last decade the Quality Assurance principles have been adopted in a number of public services such as colleges and universities. Recently stringent quality requirements have been put forward towards colleges and universities throughout Norway. These quality demands come from a number of national and international governing bodies such as the Ministry of Education and, specifically for Maritime Academies, IMO (International Maritime Organization). In connection to what is mentioned above the objective of the work carried out has been to find a way to efficiently monitor and develop the quality of the education. It is considered beneficial to approach this problem by analysing the academic organization as a whole, using organizational development as a tool to pinpoint areas of improvement. At the end of the day we want even better and more professional graduates to enter the labour marked from our college.
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Research cooperation. Sanitary engineering cooperation between Oulu and Murmansk
Статья научная
Sanitary engineering is a highly capital demanding area. Technical solutions in different cases depend on local conditions; for example, the quality of raw water and wastewater receiving watercourse. Of course, the theoretical background is always the same independent of the place. Without knowing the local conditions the research cooperation is not very useful. The best results are possible to get when persons from both countries participate in the work and work together.
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Статья научная
The training of sanitary engineers was begun in the Murmansk State Technical University in 1999 in co-operation with the University of Oulu. The University of Oulu helps acquire literature, laboratory equipment and other supplies that are needed during courses. Furthermore, the University of Oulu participates in teaching courses in water supply and sewerage. Vodokanals of the Kola region also teach courses in subject studies, organise summer training positions for the students, and employ students working on their master's theses. Research and development are very important aspects of teaching water supply and sewerage. Vodokanals, on the other hand, have a very urgent need to improve the quality of drinking water. The primary task would be to alter the quality of drinking water enough to reduce corrosion in the piping network. A movable pilot plant that is able to treat 200 to 500 m3 of water a day ought to be constructed for research and teaching purposes.
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Scientific and practical basis of cephalopods dehydration processes
Статья
Nowadays, it is relevant to solve the problems of adapting optimal resource- and energy-efficient modes to technologies for processing food raw materials. The work is focused on the analysis of the prerequisites to find similar features in the dehydration of food capillary-porous colloidal materials by means of various methods. The authors have studied the patterns of cephalopods dehydration using the example of octopus and squid under different heat treatment regimes. It has been proved that there is only one critical point characterizing the transition from moisture with a lower binding energy to moisture with a higher one, and an equation has been proposed for finding the critical humidity during dehydration of the objects been studied. A generalized mathematical model has been developed to determine the duration of the process at the current moisture content of the food material based on dimensionless similarity criteria characterizing the phenomena been investigated. The dependences of the moisture removal rate for different heat treatment methods of cephalopods are given according to their initial moisture content, the specific surface area of the material and the operating factors that determine the process. The obtained dependencies and patterns open up unique opportunities for labor-saving design in the food industry using rational operating modes of industrial enterprises, optimization of heat treatment processes in general and the creation of energy-efficient equipment new designs.
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Статья
Геохимия изотопов серы Хибинского и Ловозерского агпаитовых массивов дает возможность понять роль плюм-литосферных процессов, ответственных за палеозойскую щелочную магматическую активность в северо-восточной части Фенноскандинавского щита. Изотопный состав серы (δ34S) получен для пентландита, халькопирита и пирита из нефелиновых сиенитов с использованием масс-спектрометра с тройным коллектором (IRMS). Значения δ34S пентландита из пород Хибинского массива варьируют от +0,69 до +2,06 ‰ относительно стандарта Вена-Каньон-Дьябло-Троилит (VCDT); значительно выше значения для пирита (+ 4,92 ‰ VCDT). Ловозерский пентландит имеет значение δ34S, равное +1,48 ‰ VCDT; δ34S для халькопирита составляет +2,85 ‰ VCDT. Максимально положительные значения δ34S для сульфидов Ловозерского массива получены для пирита (от +5,41 до +6,30 ‰ VCDT). Сравнение полученных данных с данными по изотопии серы для карбонатитов Хибин, Салланлатви, Себлъявра, Вуориярви, Салмагоры и Ковдора указывает на более позднее образование карбонатитов относительно связанных с ними щелочных пород. Геохимические исследования изотопов серы показывают, что первичным магматическим источником Хибинского и Ловозерского щелочных массивов является метасоматизированная субконтинентальная литосферная мантия (SCLM). Сделано предположение, что высокие значения δ34S для SCLM (от +1 до +6 ‰ VCDT) обусловлены субдукцией архейской коры, обогащенной тяжелым 34S изотопом серы
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Статья научная
In the paper comparative design solutions of the pr oject concerning the transportation of multi- component gas from the Stockman deposit developed by Russian domestic standards (General Standards for the design of Industrial Projects) and simulator program OLGA have been considered. Existing distinctions (more then 30 %) are demonstrated for the two project solutions for intermittent operating conditions of submarine pipeline for the first stage of field development
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Статья научная
The idea of using the cavitation energy in food industry appeared in the middle of the last century, but due to absence of efficient machineries and developed process theory this method was not used. The attractiveness of using the effects of cavitation in the food industry lies in the possibility of a significant intensification of such most labour and energy-consuming processes as grinding, homogenization, dispersion, emulsification of food disperse systems. Nowadays, lots of works all around the world are dedicated to this phenomenon. This scientific direction has gained it's actuality with the world rate technic development allowing to create the more powerful machineries, capable to processing large volume of liquid. The development of new researching method has made the problem of using the cavitation energy - which has both hydrodynamic and acoustic nature - more attractive. The advantages of using the effects of cavitation on food media have been presented. The expediency of using cavitation in various sectors of the food industry: baking industry, meat industry and dairy industry has been proved...
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Статья научная
This article is a paper of the author on the International Conference «Northern Universities» which took place from 16 to 18 October 1997 in the MSTU.
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Статья научная
A new 3 - D fluid dynamics model of multilayered media has been developed, with complex burial history and capable for calibration. This new method extends the 1.5 - D approach to the solution of forward and inverse problems for excess formation pressure evolution at the basin scale, earlier proposed by the authors. The concept of a laterally conductive reservoir carrier among massive permeable rocks has been introduced. The system of sealing faults has been considered as pressure barriers in the relevant latera l drainage system. The vertical and lateral directions of pore fluid migration have been accounted recursively in two relevant mass conservation models. It allows building of an effective numerical scheme capable of modelling formation pressure compartmentalization and calibrating the sealing properties of surrounding faults. We introduce as a goal of calibration the set of independent fault attributes sensitive to the seal properties and sufficient to describe the lateral barrier. A software program packag e based on this approach has been developed, and some results of its practical application for fault analysis in the North Sea basin have been discussed.
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The effective basin model concept and fast 3-D overpressure modelling in basin time scale
Статья научная
The approaches and background Earth model applicable for overpressure phenomenon investigation have been reviewed and systemised in the context of their applicability for pre-drill and while-drill prediction. An Effective Basin Model (EBM) concept has been introduced basing on the successive assumption simplifying full-scale basin modelling solutions. The EBM concept allows to incorporate 1-D and 2-D approaches to overpressure modelling in basin time scale. The relevant combine 3-D overpressure modelling operator has been designed. The operator has been capable to account for the main overpressuring mechanisms including 3-D pressure communication phenomena (centroid effect, dipping aquifer beds, pressure drop across the sealing faults, etc.). A stable implicit scheme has been developed for numerical pressure solutions. The scheme reveals absolute numerical stability within the practically important range of model parameters and combined grid properties. The benefits of the developed combined 3-D HD approach versus full scale 3-D regular grid solution in computing speed is estimated to be about N⋅(105-106) times for the Earth model cube based on about 109 cells. The applicability of the new fast 3-D modelling scheme has been tested on real geology settings and has been checked against real data. The Gulf of Mexico basin has been used for prototyping of the centroid effect on salt induced positive Cainozoic structures. The North Sea tectonics has been used for simulating overpressured fault sealed compartments.
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The first find of diamond on the Sredny and Rybachy peninsulas in the north-eastern Baltic shield
Статья научная
The regular features of the region's spatial-temporal evolution have been discussed. Based on geodynamic analysis and the time scale of the crust formation in the eastern Baltic Shield, it is defined, that the most promising search areas for diamond-bearing rocks are intersections of deep lithospheric faults and discovered belts of possible diamond-bearing kimberlitic magmatism. The paper suggests the most promising search areas for diamond-bearing kimberlitic explosion pipes that can be united in the single diamond-bearing Norwegian-Mesensky belt. Prospecting for diamonds was carried out in the area of the Rybachy and Sredny Peninsulas in 2005-2007. Detailed decoding of large-scale aerial photographs and in situ measuring of fractures in the northern margin of the Sredny Peninsula allowed defining prospective intersection nodes of deep faults. Heavy mineral concentrate has been sampled here and indicated diamonds and associated minerals. They can suggest either native wash-out origins, or immediate scouring of Paleo-marine terraces that used to be rich in these minerals...
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