State Of Dynamic Equilibrium Research Articles

Equation for the envelope of a relativistic electron beam propagating in a resistive plasma channel during the evolution of resistive hose instability

Kinetic methods are used to derive the transport equations, virial equation, dynamic equilibrium condition, and the equation of the envelope of an axially symmetric paraxial relativistic electron beam propagating in an Ohmic plasma channel during the evolution of resistive firehose instability. The equation of the beam envelope is generalized by taking this instability into account.

Morphodynamics of a bedrock‐alluvial meander bend that incises as it migrates outward: approximate solution of permanent form

AbstractIn meandering rivers cut into bedrock, erosion across a channel cross‐section can be strongly asymmetric. At a meander apex, deep undercutting of the outer bank can result in the formation of a hanging cliff (which may drive hillslope failure), whereas the inner bank adjoins a slip‐off slope that connects to the hillslope itself. Here we propose a physically‐based model for predicting channel planform migration and incision, point bar and slip‐off slope formation, bedrock abrasion, the spatial distribution of alluvial cover, and adaptation of channel width in a mixed bedrock‐alluvial channel. We simplify the analysis by considering a numerical model of steady, uniform bend flow satisfying cyclic boundary conditions. Thus in our analysis, ‘sediment supply’, i.e. the total volume of alluvium in the system, is conserved. In our numerical simulations, the migration rate of the outer bank is a specified parameter. Our simulations demonstrate the existence of an approximate state of dynamic equilibrium corresponding to a near‐solution of permanent form in which a bend of constant curvature, width, cross‐sectional shape and alluvial cover distribution migrates diagonally downward at constant speed, leaving a bedrock equivalent of a point bar on the inside of the bend. Channel width is set internally by the processes of migration and incision. We find that equilibrium width increases with increasing sediment supply, but is insensitive to outer bank migration rate. The slope of the bedrock point bar varies inversely with both outer bank migration rate and sediment supply. Although the migration rate of the outer bank is externally imposed here, we discuss a model modification that would allow lateral side‐wall abrasion to be treated in a manner similar to the process of bedrock incision. Copyright © 2016 John Wiley & Sons, Ltd.

Constant Strain Rate Uniaxial Compression of Green Sandstone during SHPB Tests Driven by Pendulum Hammer

During the Split-Hopkinson pressure bar (SHPB) tests driven by pendulum hammer, employing a proper special shape striker is an effective way to obtain dynamic stress equilibrium condition and to get constant strain rate of the rock specimen. To find the proper special shape striker, a striker with a cambered surface was introduced and eight geometrically different hammers were designed to analyze the effect of hammer geometry on the waveform of excited incident stress waves. Based on experiments and simulations, parameter effects, including the cambered hammer curvature radius and hammer diameter, length, and impact velocity, on the incident wave shape were examined. These parametric studies provided guidelines for achieving constant strain rates in rock specimens during SHPB tests. The use of different diameter hammers was noted for shaping stress-time curves to follow the stress-strain behavior of green sandstone. Finally, to examine the applicability of using hammer geometry for shaping incident waves to achieve constant strain rate, SHPB tests on green sandstone specimens were conducted. The results demonstrated that a constant strain rate (100 s−1) lasting for 70 μs was achieved with the 8# hammer (3.7 kg; curvature radius, diameter, and length of 100, 70, and 126.3 mm, resp.). In addition, dynamic experiments on green sandstone were carried out under various strain rates and the results showed that the initial tangential modulus was almost unaffected by strain rate. The strain at peak stress tended to increase with rising strain rate and the dynamic strength of green sandstone showed an apparent rate dependency.

Thermal neutrons of the terrestrial origin in the Brazilian region

Dynamics of near ground concentration of ambient thermal neutrons (TNs) was studied using data of neutron detectors of the COsmic-ray Soil Moisture Observing System (COSMOS) network and those of the Laboratory of environmental radiation of the Instituto Tecnologico de Aeronautica (Brazil). A significant excess of TN count rate over that of rapid ones was found in two COSMOS probes located in Brazil and other sites in North America and Europe. The effect was explained in terms of neutron production in nuclear (α, n) reactions initiated by decay of radon gas comprised in the ground rather than in the atmosphere. A revealed strongly marked diurnal variation of the TN concentration proved to be in antiphase with air temperature that is characteristic for particles in thermal equilibrium with air. A previously unknown effect of saturation of nighttime TN concentration was observed. It is explained in terms of a dynamic equilibrium state, which sets in the absence of vertical convection between the neutrons escaping from the ground and their losses in nuclear reaction in the air. The results described can be used for the determination of ground concentration of ambient radon and its dynamics in boundary layer of atmosphere as well as in other geophysical studies.

Motion characteristics of bilayered extensible Timoshenko microbeams

The nonlinear motion characteristics of a bilayered Timoshenko microbeam is analysed taking into account all the translational (i.e. longitudinal and transverse) and rotational motions; the effect of size is included through use of the modified couple stress theory. Considering a continuous variation through the thickness for the displacement field, the geometrically nonlinear strain terms are developed. Relating these strain terms to stress terms, via use of constitutive relations, leads to a stress tensor in terms of the displacement field; the same is applied to the symmetric curvature tensor and the deviatoric part of the symmetric couple stress tensor by means of a constitutive relation incorporating size effects. The potential energy of the bilayered microbeam is formulated via the modified couple stress theory. The kinetic energy along with the work of an external dynamic force is formulated in terms of the displacement field of the bilayered microbeam. A dynamic equilibrium state is obtained via balancing the energy and work. Three-dimensional reduced-order models for the transverse, longitudinal, and rotational motions are obtained via Galerkin's method. These coupled models are solved via a continuation method coupled with direct time-integration. The resonant responses are constructed with special consideration to the effects of the length-scale parameter and the material percentage and thickness of each layer; a comparison is also made between the motion characteristics of the bilayered and monolayered microbeam.

Factors controlling Cenozoic anthracogenesis in the Polish Lowlands

The accumulation of large amounts of phytogenic matter, leading to the formation of lignite deposits of economic importance, has been determined by two groups of external factors: (a) climatic factors determining the indispensable production of organic matter and (b) geological factors allowing preservation of this matter in the sediment and its diagenetic transformation in the process of coalification. The overriding item among climatic factors was obviously the production of suitable amounts of phytogenic matter. It could be accumulated only under favourable vegetation conditions and therefore a warm and humid climate was a condition sine qua non for the intensive production of phytogenic matter. Problems of lignite origin do not generally relate to the lack of production of phytogenic material, but to preventing preservation in the sediment due to rapid oxidation of this material in very warm conditions. Therefore, the coal-forming process was constrained by two critical temperature values, which had to be neither too low nor too high, wherein sufficiently high humidity persisted throughout the process. Therefore, the range of mean annual temperature, which ensured favourable conditions for the growth and preservation of phytogenic matter, was from approx. 15.5 to 24°C. In the Cenozoic, such conditions commenced in the Early Oligocene and persisted up to the later Miocene – this was the interval of the most intense anthracogenesis in the Polish Lowlands. In the widespread lowland areas, lush swamp forests and peat fens developed, and thick lignite seams reflect the accumulation of phytogenic matter. This interval began with the cooling at the Eocene/Oligocene boundary and terminated at the beginning of the next cooling and drying phase known as that of the “C4 grassland” in the Late Miocene. Both the critical points are related to the surpassing of temperature limits: too high for the preservation of phytogenic deposits, and too low for the extensive development of lignite-forming vegetation. An important condition for the emergence of a large thickness of phytogenic sediments is primarily an existence of the accomodation space, where a considerable amount of plant matter might accumulate. This occurred only in conditions of dynamic equilibrium between the growth of plant matter and the lowering of the depositional surface, which ensured stabilization of the groundwater level. The rate of subsidence of the depositional surface must be balanced by the rate of vegetation growth. Therefore, no single lignite seam corresponding in age to the whole period of potential accumulation was formed at that time. Rather, a few lignite seams, separated by thick successions of mineral deposits, then formed. The vegetation of the wetlands which created the individual lignite seams was similar, this being mostly a facies element. Differences in the composition of vegetation are found mainly in plant communities outside peat-fens and it is the plants outside of the wetlands which allowed for subsequent dating of the lignite seams. The thermophilous vegetation was replaced by plants of lower thermal requirements during the progressive climate cooling towards the end of the Miocene. The ultimate cooling and completion of peat/lignite production was generated by the Middle Miocene uplift of the Carpathians arc in the Alpine orogeny. This natural barrier considerably limited the circulation of warm and humid air masses from the south to the Polish Lowlands area.

Theoretical Analysis of Drug Dissolution in Micellar Media

A new theoretical approach combining convective diffusion and surface dissolution kinetics has been applied to micellar systems and tested on experimental data available for both rotating disk apparatus and particles. The micelles are shown to be in the state of dynamic equilibrium with solution for most systems but nanoparticles. For ionizable molecules, the variation of partition coefficient across diffusion boundary layer may affect the diffusivity. The intrinsic dissolution rate is generally a nonlinear function of the equilibrium concentration, c0, in which the diffusion kinetic coefficient, βD, surface kinetic coefficient, β0, and total kinetic coefficient of dissolution, β, all typically decrease as functions of c0 (or increasing micellar concentration, Mc). The observed absolute values of β0 are usually in the order of 10−3-10−2 cm/s and strongly dependent on the nature of surfactant and solute molecules. For dissolution of particles, the surface kinetics tend to become the rate-limiting step.

Forgetting in Reinforcement Learning Links Sustained Dopamine Signals to Motivation.

It has been suggested that dopamine (DA) represents reward-prediction-error (RPE) defined in reinforcement learning and therefore DA responds to unpredicted but not predicted reward. However, recent studies have found DA response sustained towards predictable reward in tasks involving self-paced behavior, and suggested that this response represents a motivational signal. We have previously shown that RPE can sustain if there is decay/forgetting of learned-values, which can be implemented as decay of synaptic strengths storing learned-values. This account, however, did not explain the suggested link between tonic/sustained DA and motivation. In the present work, we explored the motivational effects of the value-decay in self-paced approach behavior, modeled as a series of ‘Go’ or ‘No-Go’ selections towards a goal. Through simulations, we found that the value-decay can enhance motivation, specifically, facilitate fast goal-reaching, albeit counterintuitively. Mathematical analyses revealed that underlying potential mechanisms are twofold: (1) decay-induced sustained RPE creates a gradient of ‘Go’ values towards a goal, and (2) value-contrasts between ‘Go’ and ‘No-Go’ are generated because while chosen values are continually updated, unchosen values simply decay. Our model provides potential explanations for the key experimental findings that suggest DA's roles in motivation: (i) slowdown of behavior by post-training blockade of DA signaling, (ii) observations that DA blockade severely impairs effortful actions to obtain rewards while largely sparing seeking of easily obtainable rewards, and (iii) relationships between the reward amount, the level of motivation reflected in the speed of behavior, and the average level of DA. These results indicate that reinforcement learning with value-decay, or forgetting, provides a parsimonious mechanistic account for the DA's roles in value-learning and motivation. Our results also suggest that when biological systems for value-learning are active even though learning has apparently converged, the systems might be in a state of dynamic equilibrium, where learning and forgetting are balanced.

Nanoindentation investigation of the stress exponent for the creep of dung beetle (Copris ochus Motschulsky) cuticle

ABSTACTWith the rapid development of bionic science, especially the progress that has been made in the fields of biomaterials and biomimetics, there is now great interest in the surface and internal mechanical properties of biological materials at the micro- and nanoscale. The study of micro- and nanoscale biomaterial mechanical properties could enable interdisciplinary applications in materials science, biological science and bionic science. Dung beetle (Copris ochus Motschulsky) cuticle is a viscoelastic material that is both viscous and flexible via elastic deformation under external forces; where stress σ, strain ϵ and elastic modulus E are related in the following way: σ = Eϵ. In addition, as σ is related to the rate of strain, time is also a factor. The stress-strain relationships of various parts of dung beetle cuticle were investigated in this paper. As time increased, the stress and strain of the material were found to decrease and increase, respectively, indicating that when the material was indented for a certain period, the interaction force between the indenter and the material gradually achieved a state of dynamic equilibrium. However, strain continued to occur until reaching a point of equilibrium because of the creep phenomenon. The stress-strain curves showed a strong character in each holding time condition: the longer the holding time, the more flattened the stress-strain curve. These findings will be useful in the advanced design of strong, lightweight, and biomimetic composites.

Deactivation of Au/CeO2 catalysts during CO oxidation: Influence of pretreatment and reaction conditions

The influence of the pretreatment on the activity and deactivation behavior of a high surface area 4.5wt.% Au/CeO2 catalyst during low temperature CO oxidation reaction (Treact=80°C) was studied in a multi-technique approach. Furthermore, the influence of changing from a close-to-stoichiometric (1% CO, 1% O2 rest N2), to O2-rich (1% CO, 5% O2 rest N2) and CO-rich (5% CO, 1% O2 rest N2) gas mixtures was investigated. Findings from kinetic and deactivation measurements are correlated with experimental data on the Au particle size, Au and Ce oxidation state, and on the nature of adsorbed species after the different pretreatments and during/after subsequent reaction, which were obtained by operando and in situ methods such as operando X-ray absorption spectroscopy and IR spectroscopy, as well as ex situ X-ray photoelectron spectroscopy, X-ray diffraction and transmission electron microscopy. These data revealed that the pretreatment significantly affects catalyst structure, surface composition and activity in the initial stages of the reaction. During reaction, however, the catalyst surface composition approaches a dynamic equilibrium state, which is largely reached already after 10min time on stream and which is independent of the pretreatment. Consequently, under present reaction conditions, longer-term deactivation is not dominated by the buildup of site blocking adsorbed species such as surface carbonates, but by slow processes such as reduction/re-oxidation of the bulk support during the reaction in combination with a modest irreversible Au NP growth.

Immunity by equilibrium.

The classical model of immunity posits that the immune system reacts to pathogens and injury and restores homeostasis. Indeed, a century of research has uncovered the means and mechanisms by which the immune system recognizes danger and regulates its own activity. However, this classical model does not fully explain complex phenomena, such as tolerance, allergy, the increased prevalence of inflammatory pathologies in industrialized nations and immunity to multiple infections. In this Essay, I propose a model of immunity that is based on equilibrium, in which the healthy immune system is always active and in a state of dynamic equilibrium between antagonistic types of response. This equilibrium is regulated both by the internal milieu and by the microbial environment. As a result, alteration of the internal milieu or microbial environment leads to immune disequilibrium, which determines tolerance, protective immunity and inflammatory pathology.

In-situcharacterization of the early stage of pipeline steel corrosion in bicarbonate solutions by electrochemical atomic force microscopy

An electrochemical atomic force microscope was used to characterize the early stage of corrosion of an X100 pipeline steel in bicarbonate solutions with varied concentrations by synchronous measurements of electrochemical potential of the steel and its topographic evolution with time. Upon immersion of the steel in 0.01 M NaHCO3 solution, both electrochemical potential and topographic profile are associated with the dissolution of air-formed oxides present on the steel surface. The potential drops and the surface roughness increases rapidly. When corrosion of the steel occurs, the potential further drops and the surface roughness of the steel increases gradually. As the steel corrosion achieves a steady state, the generation of corrosion products reaches a dynamic equilibrium state. The surface roughness maintain an approximately stable value. In solutions containing increased bicarbonate concentrations, such as 0.1 M and 0.5 M NaHCO3, the steel can be passivated. The formed passive film can eliminate some surface features and improves the surface roughness. The topographic profile of the steel surface in 0.5 M NaHCO3 solution is smoother than that in 0.1 M solution. The surface features within 20 nm become eliminated after 4500 s of immersion in 0.1 M NaHCO3 solution, while larger features within 50 nm in size are eliminated in 0.5 M NaHCO3 solution in the same time period. Copyright © 2016 John Wiley & Sons, Ltd.

Conditions of Sediment Transport of Styr Basin Rivers

The paper presents the results of studies of the conditions of sediment transport of Styr basin rivers, tributaries of the right bank of Pripyat, which were held on 9 rivers of the basin and 2 streams of the Styr River (Stara Styr and Prostyr). According to 30 representative cross-sections of the studied rivers, the hydraulic parameters of channels are measured and channel alluvium is sampled to determine its coarseness. The average flow rates under the bankfull stage are set for the mentioned areas and non-eroding and eroding velocities of the stream flow are calculated. It is determined that the passage of bankfull stages in edges complies with the conditions of dynamic equilibrium of the erosion-accumulative processes. The ratios of average flow velocities under the bankfull stage with non-eroding and eroding velocities enable determining the orientation of channel deformations in the areas of the rivers. A new approach to the determination of non-eroding velocities for unexplored areas of the rivers is represented, which is based on the dependence of non-eroding and average flow velocities at the bankfull stage. It is shown that an increase in slopes and velocities of the stream of the Styr River cause the activation of channel processes down the river.DOI: http://dx.doi.org/10.5755/j01.erem.72.1.14035

Regional Instability in the Abundance of Open Stands in the Boreal Forest of Eastern Canada

Fires are a key disturbance of boreal forests. In fact, they are the main source of renewal and evolution for forest stands. The variability of fire through space and time results in a diversified forest mosaic, altering their species composition, structure and productivity. A resilient forest is assumed to be in a state of dynamic equilibrium with the fire regime, so that the composition, age structure and succession stages of forests should be consistent with the fire regime. Dense spruce-moss stands tend, however, to diminish in favour of more open stands similar to spruce-lichen stands when subjected to more frequent and recurring disturbances. This study therefore focused on the effects of spatial and temporal variations in burn rates on the proportion of open stands over a large geographic area (175,000 km2) covered by black spruce (Picea mariana (Mill.) Britton, Sterns, Poggenb.). The study area was divided into 10 different zones according to burn rates, as measured using fire-related data collected between 1940 and 2006. To test if the abundance of open stands was unstable over time and not in equilibrium with the current fire regime, forest succession was simulated using a landscape dynamics model that showed that the abundance of open stands should increase progressively over time in zones where the average burn rate is high. The proportion of open stands generated during a specific historical period is correlated with the burn rate observed during the same period. Rising annual burn rates over the past two decades have thereby resulted in an immediate increase in the proportion of open stands. There is therefore a difference between the current proportion of open stands and the one expected if vegetation was in equilibrium with the disturbance regime, reflecting an instability that may significantly impact the way forest resources are managed. It is apparent from this study that forestry planning should consider the risks associated with the temporal variability of fire regimes on the forest ecosystem, as the resulting changes can have a significant impact on biodiversity and allowable cut estimates.

Airflow and optic flow mediate antennal positioning in flying honeybees.

To maintain their speeds during navigation, insects rely on feedback from their visual and mechanosensory modalities. Although optic flow plays an essential role in speed determination, it is less reliable under conditions of low light or sparse landmarks. Under such conditions, insects rely on feedback from antennal mechanosensors but it is not clear how these inputs combine to elicit flight-related antennal behaviours. We here show that antennal movements of the honeybee, Apis mellifera, are governed by combined visual and antennal mechanosensory inputs. Frontal airflow, as experienced during forward flight, causes antennae to actively move forward as a sigmoidal function of absolute airspeed values. However, corresponding front-to-back optic flow causes antennae to move backward, as a linear function of relative optic flow, opposite the airspeed response. When combined, these inputs maintain antennal position in a state of dynamic equilibrium.

Analysis of steelmaking kinetics from IMPHOS pilot plant data

It is widely accepted that understanding the kinetics of steelmaking is a complex task, and reliable and validated kinetics models are required for developing successful steelmaking process models. Therefore, as an initial attempt, this paper analyses the applicability of first order kinetics to explain the steelmaking reaction kinetics using the published data in the IMproving Phosphorus Refining research report. The process data for 20 heats in a 6 tonne pilot plant were analysed for the removal of carbon, silicon, manganese and phosphorus using first order kinetics with static and dynamic equilibrium conditions. It was observed that the removal behaviour of silicon closely followed a first order kinetics relationship, while that of carbon only approximately followed a first order kinetics relationship. The removal of manganese did not show a good degree of fit with first order kinetics using static equilibrium condition, but a clear improvement was observed when calculated using dynamic equilibrium condition. In contrast, the kinetics of phosphorus oxidation did not follow any first order relationship.

Dynamic Equilibrium Model for a Bulk Nanobubble and a Microbubble Partly Covered with Hydrophobic Material.

The dynamic equilibrium model for a bulk nanobubble partly covered with hydrophobic material in water is theoretically and numerically studied. The gas diffusion into a bubble near the peripheral edge of the hydrophobic material on the bubble surface balances that out of the bubble from the other part of the uncovered bubble surface. In the present model, gas diffusion in quiescent liquid is assumed and there is no liquid flow. The total changes of energy and entropy are both zero as it is a kind of equilibrium state. The main origin of the dynamic equilibrium state is the gradient of chemical potential of gas near the peripheral edge of the hydrophobic material. It is caused by the permanent attractive potential of a hydrophobic material to gas molecules dissolved in liquid water as there is permanent repulsion of a hydrophobic material against liquid water. Thus, the gas supply will not terminate. It is numerically shown that stable nanobubble could be present when the fraction of surface coverage by hydrophobic material is from about 0.5 to 1. The stable size of a nanobubble changes with the liquid temperature as well as the degree of gas saturation of water. In slightly degassed water, not only a nanobubble but also a microbubble could be stable in mass balance when the fraction of surface coverage for a microbubble is on the order of 10-4 or less. For hydrophilic materials, however, a bubble could not be stable unless the fraction of the surface coverage is exactly 1. It is suggested that in many experiments of bulk nanobubbles there could be aggregates of nanobubbles.

Pulse shaping with soft material for SHPB

In the split Hopkinson pressure bar (SHPB) experiment, the state of dynamic stress equilibrium should be achieved over most of the test duration. Therefore, pulse shaping techniques which can modify the profile of the incident pulse are usually needed. In this paper, a new method for SHPB incident pulse shaping is presented. The vacuum cement material of which the strength can be ignored is used as the pulse shaper. The experimental results show that, with this method, satisfactory shaping effect can be obtained in a wide application scope. Combining the adjustment of the impact velocity and the amount of the vacuum cement, different shaping results such as sinusoid, slow-rise trapezoid can be obtained. This result would meet the needs of the dynamic stress equilibrium or constant strain rate loading in SHPB experiments. The numerical simulation result indicates that the shaping function of the material is mainly due to the radial inertial effect in the high velocity deformation process of vacuum cement.

Challenges to the representation of suspended sediment transfer using a depth‐averaged flux

AbstractThe sediment saturation recovery process (i.e. the adaptation of suspended sediment concentration [SSC] to local forcing) is the main feature of the non‐equilibrium suspended sediment transport (SST) frequently occurring in fluvial, estuarine and coastal waters. In order to quantitatively describe this phenomenon, a series solution is analytically derived, including the evolution of both vertical SSC profile and near‐bed sediment flux (NBSF), and is verified by net erosion and net deposition experiments, respectively. The results suggest that the sediment saturation recovery process involves vertically varying fluxes that are not represented correctly by depth‐averaging. Consequently, a vertical two‐dimensional (2D) combined scheme is established and applied respectively in to a dredged trench and to a sand wave feature to demonstrate this argument. By analyzing the variations of the calculated depth‐averaged SSC and NBSF we reveal that the equilibrium state presented by the sediment carrying capacity (SCC) form of the NBSF, which is usually applied in depth‐integrated SST models, lags behind the actual dynamic bed equilibrium state. Moreover, the key factor α, the so‐called saturation recovery coefficient within this form, is not only a function of local Rouse number but also is influenced by the local SSC profile. Finally, a three‐dimensional (3D) non‐orthogonal curvilinear body‐fitted SST model is developed and validated in the Yangtze estuary, China, combined with the in situ hourly hydrographic data from August 14–15, 2007 during spring tide in the wet season. Model results confirm that the vertically varying sediment saturation recovery process, the discrepancies between the actual and SCC form of NBSF and non‐constant value of α are significant in actual real geomorphic cases. The quantitative morphological change resulting from variations in environmental conditions may not be correctly represented by uncorrected depth‐integrated SST models if they do not treat the effects of vertical motion on the sediment saturation recovery process. Copyright © 2016 John Wiley & Sons, Ltd.

Eco-Infrastructural Labs for Urban Utopias Moscow as Slow Metropolis

AbstractThe future project of cities and highly attractive places must respond to global environmental goals, to historical and architectural heritage, and to the needs of local environments and quality of life.Taking on that issue, this research project originates from the exchange of experiences between the Polytechnic University of the Marches (Italy), the Moscow State Forest University and the A&P Studio (Architettura&Paesaggio, Italy), who initiated the research on urban landscapes with particular reference to the sustainable regeneration in certain parts of the metropolitan area of Moscow, the saturated city at the top of the network of global cities, taken as a case study on the world level.The trial field is the net of the “infra” spaces of Moscow, which is re-established by architecture restoring links which are broken by the infrastructure.Infrastructure and its spaces, generally regarded as the developing drive behind the territory, in this study become the re-governing instrument of the city and opportunity for wise dialogue between the economic-financial, environmental and cultural spheres. That is possible through the project of multi-functional Hubs: they recover the marginal spaces of railway areas and tends to restore a state of dynamic equilibrium between multimodal mobility, parks and a functional mix of public services.From the “Social Condenser” of Soviet Constructivism, the research alights on the catalysts (the new Hubs) of the collective life, which lead to the innovative use of public transport in relieving areas saturated by private transport. «Would it be possible to use the highway as a means of education?» (The view from the road, Kevin Lynch 1964). The “Moskva 7 Kholmov” idea-project replies by introjecting previous theories and more mature situations (Archigram, Yona Friedman, OMA/Rem Koolhaas) with ecological theories (Forman and Sperling).The study suggests the overcoming of the evolutionary trauma of the metropolis in a project that reunites the senses of place and time through innovative architecture dedicated to people on the move. By skilfully balancing the infrastructural, urban, ecological and landscaping points of view, the new architecture fulfils the role of infrastructural shock absorbers, thanks to which the “Slow Metropolis” becomes a possible utopia: Moscow, urban-architectural utopia of the Twenties, becomes a positive example of the functioning of infrastructure and architecture for a mobile society.