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The problem of short-term sea level forecasting in the area of Сape Kamenny in the Ob’ Bay has become important since the Novoportovsky terminal (known as “Arctic Gate”) began operating for year-round oil shipment. The tankers loading the oil from the terminal have to pass through relatively shallow waters, located to the north, limiting the vessels draft. Thereby a short-term water level forecast is required relative to the lowest theoretical level for tankers loading at the terminal. The year-round hourly observations using buoy level gauges with a satellite channel of data transmission are organized for quick level monitoring directly in the area of Cape Kamenny. The results of the harmonic analysis of water level observations in the area of Cape Kamenny for 2016–2021 showed significant seasonal variability of amplitudes and phases of the wave М2 in the annual cycle, as well as their interannual variability due to various ice conditions of the Ob’ Bay (light, medium, heavy). Based on these results, the processing and analysis of observations data over the last month are performed by the end of each month. According to these results, the current values of harmonic constants, dependent on actual ice conditions are specified and calculation of the tide is carried out for the next month. The calculation of the forecast values of the total level is composed of calculated tide and short term (with a lead time of up to 5 days) forecast of non-periodic level fluctuations using the three-dimensional hydrodynamic model of joint water and ice circulation AARI-IOCM. At the final stage of the forecast preparation, the predicted level, usually calculated relative to the conditional long term average annual value, is bound to the lowest theoretical level (according to the current values of the level gauge) and transferred to the operator of the terminal and to the tanker. The hourly observations of water level in the area of Cape Kamenny and level forecasting have been carried out since 2017 and are still continuing.

The ice cover of the Gulf of Ob is formed in an extended zone, where the sea and fresh waters are mixed. This study aims to evaluate certain physical and mechanical characteristics of such ice. It examines data on a complex of physical and mechanical fast ice characteristics in the Ob’ Bay, obtained in the course of field studies over the last 30 years. The total amount of data available to the team of authors exceeds 200 cores, sampled in the Ob’ Bay (from Novy Port to the boundary between the Bay and the Kara Sea) in different years and in different months of the ice season.Processed data on ice temperature are presented, as well as information on the evolution of integral ice temperature during ice season. The change of integral ice salinity in the Ob’ Bay with geographic latitude is identified and shown, and the function approximating this change is given.The estimates of average density and porosity of ice by thickness are presented. The effect of mineral inclusions on the increase in ice density is considered.An analysis was carried out of the correspondence between the field data on fresh and saline ice sample strength in uniaxial compression (with the load application parallel to the ice cover surface) with theoretical strength estimates from Russian and foreign scientific and methodological literature, based on the data obtained on physical and mechanical ice characteristics in the Ob’ Bay. A generalized estimate of the saline ice strength limit in the Ob’ Bay, obtained in uniaxial compression parallel to the surface of ice accumulation is given, as well as its approximation by lognormal distribution.The results obtained in the analysis of the strength characteristics of ice in the Gulf of Ob can be used for practical purposes. The results may also prove useful in terms of contribution to theoretical knowledge on the experimental mechanics of ice in desalinated water bodies.

This paper will share the findings of time-lapse monitoring from two corrosion surveys conducted four years apart in the subject well; present a new processing methodology that improved metal thickness estimation and yielded better results when applied to data from two legacy wells; and describe a novel surveillance tool of unique design that was also deployed in the subject well. The positive and encouraging results achieved using this tool will also be discussed. Electromagnetic pulse surveys were conducted in 2016 and 2020 to evaluate independently the metal loss in three casing barriers. The 2016 analysis involved a simplistic data processing method. A more sophisticated processing technique was recently applied to both surveys (2016 and 2020). This new method estimates the thickness for each barrier through forward modelling based on the numerical solution of the Maxwell equations. A newly introduced electromagnetic tool was also run in combination. This is a unique approach because it provides a segmented electromagnetic metal thickness evaluation of the first barrier without the need for pad contacts with the casing wall. The simplistic processing from 2016 assumed, for each barrier, a baseline for the tool readings that corresponded to the nominal casing thickness. It then translated the deflections from this baseline into a metal loss or gain. These figures were output only when they exceeded the tool's accuracy. The advanced processing that was used in 2020, which is based on forward modelling, estimated less metal loss in general in comparison with the 2016 survey. These results agreed with the segmented tool estimations for the first barrier, which was run in combination in 2020. This confirms the methodology's robustness and accuracy. In addition, this new method outputs metal loss figures at every depth point regardless of the tool accuracy. The new processing was applied to previously acquired data sets in two additional wells in the same field, and the obtained results were very satisfactory. The new tool, which provides a segmented electromagnetic metal thickness evaluation, also delivered exciting results by providing accurate thickness estimations in eight circumferential sectors of the casing wall without pad contact. This constitutes a substantial improvement over the existing all-round and averaged measurement offered by conventional electromagnetic tools. These segmented results enabled the client to make a better-informed decision about the well and to postpone an expensive workover. This paper confirms the necessity of time-lapse surveys for monitoring the integrity of downhole tubulars. It also proves that numerical solution of the Maxwell equations through forward modelling of acquired electromagnetic data yields robust and more accurate thickness estimations than the previously used methods. Finally, it demonstrates the effectiveness of the new segmented and contactless electromagnetic tool for assessing the first casing barrier.

В настоящей статье мы усилим утверждение гипотезы Уайголда для нильпотентных алгебр Ли над бесконечным полем, доказав, что в случае существования подмножества нильпотентной алгебры Ли $\mathfrak{g}$, состоящего из элементов ширины не превосходящей $n$ и удовлетворяющего некоторым дополнительным условиям, следует оценка на размерность коммутанта $\dim\mathfrak{g}'\leqslant n(n+1)/2$. Библиография: 9 названий.

Исследуются максимальные подалгебры Ли среди локально нильпотентных дифференцирований алгебры многочленов. Дж. Фройденбургом была высказана гипотеза о том, что треугольная алгебра Ли локально нильпотентных дифференцирований алгебры многочленов является максимальной алгеброй Ли, содержащейся в множестве локально нильпотентных дифференцирований, и гипотеза о том, что каждая максимальная алгебра Ли, содержащаяся в множестве локально нильпотентных дифференцирований, сопряжена треугольной алгебре Ли. В настоящей работе мы доказываем справедливость первой части гипотезы и приводим контрпример ко второй ее части. Также мы покажем, что при некотором естественном условии, наложенном на максимальную алгебру Ли, существует сопряжение, переводящее эту алгебру Ли в треугольную алгебру Ли. Библиография: 2 названия.

In this short note we confirm an analog of a conjecture of James Wiegold for finite dimensional nilpotent Lie algebras., 5 pages

Пусть $\mathfrak{g}$ - нильпотентная алгебра Ли. Шириной $b(x)$ элемента $x$ алгебры $\mathfrak{g}$ называется число $[\mathfrak{g}:C_{\mathfrak{g}}(x)]$. М. Р. Воном-Ли было показано, что в случае, когда ширина всех элементов алгебры Ли $\mathfrak{g}$ ограничена числом $n$, размерность коммутанта алгебры Ли не превышает $n(n+1)/2$. В настоящей статье мы покажем, что в случае $\dim \mathfrak{g} > n(n+1)/2$ для некоторого неотрицательного $n$ алгебра Ли $\mathfrak{g}$ порождается элементами ширины $>n$, таким образом, мы докажем гипотезу Джеймса Уайголда (вопрос 4.69 из Коуровской тетради) для случая нильпотентных алгебр Ли. Библиография: 4 названия.

Political culture and political activity of young people in socio-political changes is of particular significance for modern Russian society, which has been undergoing large-scale socio-economic and political reforms in recent decades. The relevance of the research is determined by the role played by young people in socio-political processes in society. Studying the attitude of young people to political processes, value orientations and civic activity of the younger generation allows us to assess the changes that have occurred in the political consciousness and determine the strategy of youth policy in the country. The purpose of the research is to identify the values and political attitudes of students, to study their attitude to political changes and events in modern Russia. System analysis, axiological and activity-based approaches are used as theoretical and methodological bases, which allow identifying and arguing the specifics of political culture and political behavior of social groups, in particular young people, continuity and General socio-cultural factors of their formation. The paper uses the method of mass sociological survey of students of all faculties of the Ural state mining University (425 respondents were interviewed) on the content and nature of the political culture of students, conducted in November-December 2018. Based on a representative mass sociological survey, the article examines the prerequisites, value orientations and activity of students in the political life of the country. the article analyzes the state of political culture of young people and the main trends in its development. Attention is paid to the issues of instability of political views among young people and activism in issues related to the spheres of interests of young people. As a result of the research, values and political orientations, as well as socio-political activity of students are established. According to the results of our research, we can conclude that in General, young people reproduce the spectrum of the main political orientations and attitudes that have developed in Russian society. The results of this research can be used in the work of secondary vocational education institutions, higher education institutions, government agencies and municipal institutions that organize work with young people.

This paper will describe pre and post workover well diagnostic and the successful water shut-off that has resulted. It also talks about the post workover survey. The well was recently completed to a new targeted reservoir and suffered from high water cut (80%) at the start of production. Proper diagnostics identified the source of water and helped in planning a successful remedial job. After water shut off the water cut dropped to zero. Post workover evaluation confirmed production from the targeted interval. Comprehensive diagnostics are crucial to designing a proper remedial job. A conventional PLT survey will describe the flow characteristics and parameters inside the wellbore only. During the job under consideration, two additional services were deployed; the Spectral Noise Logging and the High Precision Temperature sensing. Their combination with the PLT allows for the assessment of behind casing flow and the identification of active streaks of the formation. The quantification of flow rate behind casing is also achieved by modelling the temperature response from the high precision sensor. The first survey was conducted with the conventional PLT to identify the source of water. Subsequently, a high precision temperature and spectral noise log were recorded under flowing, transient, and shut-in conditions. A crossflow behind casing from the upper unperforated intervals was identified. The main liquid production is coming from the water-bearing formation that is located 15 ft above the targeted reservoir. The cement evaluation surveys that were run previously confirmed the presence of a cement channel above of the perforated interval. Based on these conclusions a remedial job was designed and conducted successfully. Another HPT/SNL survey was conducted post workover. It confirmed the absence of any further flow behind casing and that all liquid production is happening from the targeted reservoir. Surface test data showed a rapid decrease in water production to 1% post workover. This paper highlights the importance of complementing the current practice of running conventional PL surveys with two additional services: the Spectral Noise Logging and Temperature simulation/modelling using a High Precision Temperature measurement.