Влияние периодической макрошероховатости на развитие турбулентной свободной конвекции у внезапно нагреваемой вертикальной пластины

The results of numerical simulation of unsteady free convection developing near a suddenly heated plate, on which protrusions in the form of adiabatic cylinders of double height with respect to the diameter are arranged in a checkerboard pattern, are presented. The calculations were performed according to the Reynolds equations using a differential model of turbulent stresses. The range of variation of the Grashof number (plotted according to the thickness of the free convective flow), in which a significant intensification of heat transfer can be achieved, has been determined. It is shown that the best conditions for intensification are created if the longitudinal pitch in the array of protrusions is approximately twenty times the diameter of the latter.

The correlation of globalization and localization of economic processes in the context of growing global risks

The article analyses changes in the correlation between globalization and localization of economic processes in the context of increasing global instability, growing geopolitical rivalry and the emergence and spread of new global risks of technological, ecological and biological origin. The study proves that the growth of global risks leads to a modification of Maslow's hierarchy of needs towards a relative accentuation of security needs - with diverse consequences in terms of the territorial organization of economic activity and mobility. It substantiates that the expansion of global processes can lead to excessive levels of concentration and homogenization of economic processes, suppression of forms of self-organization at the local level, and creating risks of disrupting the stability of local socio-economic structures. An important consequence is the transformation of the globalization process due to a significant intensification of regional and local factors. This trend determines the formation of glocalization as a two-dimensional process in which globalization and localization trends are combined. The author postulates that the balance between the processes of globalization and localization can shift in favor of the latter due to: the exacerbation of the global competition for resources and markets in the context of cardinal technological and structural shifts in the world economy; increasing international instability amid geopolitical confrontation between old and new centers of global power; insufficient effectiveness of global responses to climate change and pandemics; risks of the digital virtual environment leading to increased national and regional regulation and fragmentation of the global digital environment; and the impact of technologies of the Fourth Industrial Revolution in the direction of strengthening localization trends in relation to global value chains.

Modern trends in development of alternative powertrain systems for non-road machinery

Continuously increasing excessive emission of exhaust gases from motor vehicles, and specifically internal combustion engines have been recognized as a major concern by most of the industrialized countries since mid- 1960s. Emission gases containing an air pollutants have been shown to impose variety of negative effects on public health and the natural environment. This leads to introduction of variety of different, alternative powertrain system solutions which could help in reduction of powertrain generated emissions. Mentioned reduction of pollutants generated by the machine can be reached by application of different powertrain system or improved utilization and control of the existing one. Several different types of solutions have been considered over years as a concepts, prototypes or trial versions. Significant intensification of recent work across the globe have led the manufacturers to get their systems to the market pre-introduction or introduction stages. Alternative powered non-road machinery, either full electric, hybrid, fuel cell, or electrified have been already presented and successfully introduced. This paper focuses on state of the art non-road machinery alternative powertrain solutions and its applications, either specific or with a nature of general purpose machine. Variety of powertrains have been presented with attention to their operational parameters and working principles. Research involves in depth considerations of energy transfer within different components of the powertrain and the entire machine.

Organic matter and its transformation rates in different sea ecosystems

The article includes proprietary data and data from literature from the last 30 years about the fluctuations in concentration and the elemental and biochemical make-up of the dissolved and particulate organic matter (DOM and POM, respectively) in the different ecosystems of the Barents Sea. The large variability of these values in both surface and deep waters is shown, depending on the intensity of the hydrological and biological processes.DOM concentrations varied from 59 to 664 μMCorg, while POM varied from 0.25 to 38.08 μMCorg. The reduction of the ice cover affected both the distribution and the qualitative composition of the DOM and the POM. This reduction, as well as the increased flow of Atlantic waters, contributed not only to an increase in the primary production of organic matter, but also to a significant intensification of redox and hydrolytic processes of its transformation, especially in the high-latitude part of the Barents Sea. The DOM of the sea is characterized by high C / P ratios, far exceeding those of Redfeld. At the same time, C / N ratios in the most productive waters are close to those of Redfeld. We highlighted four regions in the sea where concentrations of dissolved carbohydrates increase towards the bottom, which indicates that oil hydrocarbons are supplied here.

RELATIONSHIP BETWEEN GLUCOSE METABOLISM IN CANCER CELLS WITH DIFFERENT METASTATIC POTENTIAL AND CELL SENSITIVITY TO ANOIKIS

Despite the significant intensification of research on the mechanisms of anoikis, the question of how metastatic cells avoid death upon separation from the extracellular matrix remains open. The aim of the study was to investigate in vitro glucose metabolism in the cells of two variants of Lewis lung carcinoma with different metastatic potential (highly metastatic LLC cells and low metastatic LLC/R9 cells) and to analyze the relationship between metastatic potential, glucose oxidation intensity and cell sensitivity to anoikis. A comparative analysis of the studied indices showed that in conditions of deadhesive growth (which simulated the process of dissemination of metastatically active cells) LLC/R9 cells (as opposed to LLC cells) were characterized by a decreased glycolysis intensity and decreased sensitivity to anoikis. The stability of the glycolysis intensity in LLC cells during the transition to deadhesive growth conditions determined both the resistance (at least in part) of these cells to anoikis and their high metastatic potential.

Fiscal Incentives for Conflict: Evidence from India's Red Corridor

Can tax regimes shape the incentives to engage in armed conflict? Indian mining royalties benefit the States, but are set by the central government. India's Maoist belt is mineral-rich, and States are responsible for counterinsurgency operations. We exploit the introduction of a 10% ad valorem tax on iron ore that increased royalty collections of the affected states by a factor of 10. We find that the royalty hike was followed by a significant intensification of violence in districts with important iron ore deposits. The royalty increase was also followed by an increase in illegal mining activity in iron mines.

Asymmetric Ocean Response to Atmospheric Forcing in an Island Wake: A 35-Year High-Resolution Study

The present study assesses the thermal variability of the regional ocean around Madeira Island, in intraseasonal and interdecadal time scales, using a 35-year (1983–2017), 3-km horizontal resolution ocean simulation forced by a co-located atmospheric simulation, with SODA and ERA5 boundary and initial conditions, respectively. Atmosphere–ocean interactions in this region are found to be driven by the variability of two quasi-permanent tip-jets, located at the island west and east tips, especially during the summer months. The ocean response is found to be larger in the regions of higher jets speed variability, but its thermal response is highly asymmetrical. On the interdecadal time scale, a significant intensification of both jets during the analyzed period is more prominent in the east tip, but the thermal signature is mostly associated with a much reduced sea surface temperature trend near the west tip.

Not all group members are created equal: heterogeneous abilities in inter-group contests

Competition between groups is ubiquitous in social and economic life, and typically occurs between groups that are not created equal. Here we experimentally investigate the implications of this general observation on the unfolding of symmetric and asymmetric competition between groups that are either homogeneous or heterogeneous in the ability of their members to contribute to the success of the group. Our main finding is that relative to the benchmark case in which two homogeneous compete against each other, heterogeneity within groups per se has no discernable effect on competition, while introducing heterogeneity between groups leads to a significant intensification of conflict as well as increased volatility, thereby reducing earnings of contest participants and increasing inequality. We further find that heterogeneous groups share the labor much more equally than predicted by theory, and that in asymmetric contests group members change the way in which they condition their efforts on those of their peers. Implications for contest designers are discussed.

Roles of Barotropic Instability across the Moat in Inner Eyewall Decay and Outer Eyewall Intensification: Three-Dimensional Numerical Experiments

Radar imagery of some double-eyewall tropical cyclones shows that the inner eyewalls became elliptical prior to their dissipation during the eyewall replacement cycles, indicating that the barotropic instability (BI) across the moat (a.k.a. type-2 BI) may play a role. To further examine the physics of inner eyewall decay and outer eyewall intensification under the influence of the type-2 instability, three-dimensional numerical experiments are performed. In the moist full-physics run, the simulated vortex exhibits the type-2 instability and the associated azimuthal wavenumber-2 radial flow pattern. The absolute angular momentum (AAM) budget calculation indicates, after the excitation of the type-2 instability, a significant intensification in the negative radial advection of AAM at the inner eyewall. It is further shown that the changes in radial AAM advection largely result from the eddy processes associated with the type-2 instability, and contribute significantly to the inner eyewall decay. The budget calculation also suggests that the type-2 instability can accelerate the inner eyewall decay in concert with the boundary layer cut-off effect. Another dry no-physics idealised experiment is conducted and the result shows that the type-2 instability alone is able to weaken the inner eyewall and also strengthen the outer eyewall with non-negligible effect.

FIELD STUDIES OF THE OKA RIVER BANK EROSION IN 2014–2018 BY THE EROSIONAL PINS METHOD

In 2014–2018, within the middle part of the Oka River basin, on narrowed and widened sections of its floodplain, were conducted studies of the retreat rate of the channel steep banks. The method of erosional pins was used to determine the rate of changes in the floodplain edge contours on active bank slopes – sections of the relatively straight and meandering Oka channel. We established that in 2014–2017, with low floods, at the level of the lower and middle intervals of channel-forming discharges, lateral erosion was determined not so much by fluvial relief formation as by slope and anthropogenic processes. After the recession of the 2018 flood, which was close in its level and discharge to the average annual values, there was a significant intensification of the bank retreat under the direct influence of the flow and more frequent formation of hollows. The annual data and integrated research results over the five-year period indicate a significant predominance of longitudinal horizontal channel deformations and a slowdown in the rate of transverse deformations, especially in dry years. The significant role of the anthropogenic and slope components in lateral erosion of the Oka channel banks has been established.