Multi-domain Boundary Element Method in Nonlinear Liquid Sloshing Analysis for Fuel Tanks

The boundary element method is used for analysis of the non-linear sloshing response of liquid in cylindrical baffled and un-baffled fuel tanks. The liquid is supposed to be an ideal and incompressible one and its flow introduced by the vibrations of a shell is irrotational. The potential formulation is considered for the liquid domain. In this paper the free vibration analysis of the liquid sloshing in the cylindrical shell is carried out in non-linear statement. The non-linear Cauchy-Lagrange integral is involved in the problem statement and the boundary conditions were assigned on the free surface changing in time. Here we use reduced boundary element method. The problem was solved using the single-domain and multi-domain reduced boundary element methods. The fourth-order Runge-Kutta method is employed to advance the solution in the time domain. The rigid baffled tanks with different annular orifices were considered. The time-dependencies of the free surface flood level were obtained numerically for vibrations of the fluid-filled tanks with and without baffles in linear and non-linear statements

Small-scale structures in neutrals and charged aerosol particles as observed during the ECOMA/MASS rocket campaign

We present results of in situ measurements of neutral temperature during the ECOMA/MASS rocket campaign. We present and compare results of turbulence measurements conducted simultaneously by both in situ and doppler radar techniques. We show that the derived values of the turbulence energy dissipation rates are similar on average. We also find a region with a near adiabatic lapse rate with turbulence detected at the upper and lower edge. We note that it is consistent with expectation for a Kelvin-Helmholtz instability. We also present an estimate of the Schmidt numbers, Sc, for the charged aerosols that utilizes in situ measured small-scale density fluctuations of charged aerosols and both in situ and radar turbulence measurements. The derived Schmidt numbers fall within the range between 100 and 4500. This result agrees with previous estimates based on multi-frequency observations of PMSE (Rapp et al., 2008) and also with estimates of microphysical parameters presented in the companion paper by Rapp et al. (2009)

Spatial and Temporal Variability in MLT Turbulence Inferred from in situ and Ground-Based Observations During the WADIS-1 Sounding Rocket Campaign

In summer 2013 the WADIS-1 sounding rocket campaign was conducted at the Andøya Space Center (ACS) in northern Norway (69° N, 16° E). Among other things, it addressed the question of the variability in mesosphere/lower thermosphere (MLT) turbulence, both in time and space. A unique feature of the WADIS project was multi-point turbulence sounding applying different measurement techniques including rocket-borne ionization gauges, VHF MAARSY radar, and VHF EISCAT radar near Tromsø. This allowed for horizontal variability to be observed in the turbulence field in the MLT at scales from a few to 100 km. We found that the turbulence dissipation rate, ε varied in space in a wavelike manner both horizontally and in the vertical direction. This wavelike modulation reveals the same vertical wavelengths as those seen in gravity waves. We also found that the vertical mean value of radar observations of ε agrees reasonably with rocket-borne measurements. In this way defined 〈εradar〉 value reveals clear tidal modulation and results in variation by up to 2 orders of magnitude with periods of 24 h. The 〈εradar〉 value also shows 12 h and shorter (1 to a few hours) modulations resulting in one decade of variation in 〈εradar〉 magnitude. The 24 h modulation appeared to be in phase with tidal change of horizontal wind observed by SAURA-MF radar. Such wavelike and, in particular, tidal modulation of the turbulence dissipation field in the MLT region inferred from our analysis is a new finding of this work

Analysis of foreign countries’ digital economy programs (Argentina, Brazil, India and Mexico)

The article is devoted to the analysis of foreign countries’ digital economy programs. The study considers Argentina, Brazil, India and Mexico cases. The authors assess the general state and level of digitalization of the economy of these countries and the national programs adopted for the digital economy development. Next, the article examines the first programs aimed at digitalization of the economy in foreign countries. The authors identify the main problems hindering the digitalization of the economy in Argentina, Brazil, India and Mexico, the characteristic features of each program and analyze the measures taken by states to improve their positions in the world in terms of the economy digitalization. As a result of the study, the authors found that the most successful from the economic development point of view are those countries where, firstly, the digitalization of the economy is supported by the current government, and, secondly, where the systems of institutions responsible for digitalization and communications between them are well developed. The article notes that common problems for states at present are the lack of a unified regulatory framework for the digitalization of the economy, as well as differences in regional development, which, of course, slows down the pace of progress in this direction

Groundwater composition fluctuation within technogenic zones (case study: flooded coal mines in Primorsky Krai, Russia)

The paper considers groundwater composition fluctuation within technogenic zones based on evidence from the flooded coal mines of Primorye. The authors have determined the regularities of hydrogeochemical processes, specified the groundwater composition fluctuation within the technogenic complexes located in the liquidated mine areas, and identified the equilibrium phases between the studied waters and specific secondary minerals. It has been proved that water within natural-technogenic complexes in the liquidated mine areas are saturated with silicates, carbonates, sulfates, oxides, and hydroxides, which should be taken into account when designing technologies for groundwater treatment

Karst hazard assessment in the design of the main gas pipeline (South Yakutia)

The paper represents the description of the zonal and regional geological factors of geoengineering conditions which characterize the territory in South Yakutia crossed by the designed main gas pipeline. Cryogenic processes and karst are considered to be the most dangerous hazards for gas pipeline maintenance. Karst hazard assessment of the gas pipeline section made in the course of the research has involved a complex of geological methods: geoengineering, geophysical, hydrogeological, and mapping. Sections prone to karst development have been identified. The authors have suggested the measures to protect potentially hazardous sections and to ensure timely informing on sinkhole collapses

Features of Coping Behavior among Respondents with a New Coronovirus Infection

Представлены результаты эмпирического исследования совладания со стрессом и ситуацией пандемии. Выявлено, что те, кто не переболел COVID-19, демонстрируют более проблемно-ориентированный копинг в стрессовых ситуациях (p = 0,044). Респонденты, перенесшие COVID-19, реализуют проблемно-ориентированное совладание в планомерном решении актуальной трудной ситуации и конфронтативных действиях. Достоверные различия в совладании с актуальной трудной ситуацией (пандемия) между мужчинами и женщинами не выявлены.The empirical results of coping behavior with stress and the pandemic situation are presented. Participants who did not get over COVID‑19 showed more problem-oriented coping style in stressful situations (p = 0.044). Respondents who have suffered from a new coronavirus infection implement problem-oriented style in a systematic solutions and aggressive actions. Significant differences in coping behavior with the COVID‑19 pandemic between men and women were not found

First in situ measurement of the vertical distribution of ice volume in a mesospheric ice cloud during the ECOMA/MASS rocket-campaign

We present in situ observations of mesospheric ice particles with a new particle detector which combines a classical Faraday cup with the active photoionization of particles and subsequent detection of photoelectrons. Our observations of charged particles and free electrons within a decaying PMSE-layer reveal that the presence of charged particles is a necessary but not sufficient condition for the presence of PMSE. That is, additional requirements like a sufficiently large electron density – which we here estimate to be on the order of ~100 cm−3 – and the presence of small scale structures (commonly assumed to be caused by turbulence) need to be satisfied. Our photoelectron measurements reveal a very strong horizontal structuring of the investigated ice layer, i.e., a very broad layer (82–88 km) seen on the upleg is replaced by a narrow layer from 84.5–86 km only 50 km apart on the downleg of the rocket flight. Importantly, the qualitative structure of these photoelectron profiles is in remarkable qualitative agreement with photometer measurements on the same rocket thus demonstrating the reliability of this new technique. We then show that the photoelectron currents are a unique function of the ice particle volume density (and hence ice mass) within an uncertainty of only 15% and we derive corresponding altitude profiles of ice volume densities. Derived values are in the range ~2–8×10−14 cm3/cm3 (corresponding to mass densities of ~20–80 ng/m3, and water vapor mixing ratios of 3–12 ppm) and are the first such estimates with the unique spatial resolution of an in situ measurement