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1
Zhou, Haiguang. "Wind Structure of a Subtropical Squall Line in China: Results from Dual-Doppler Radar Data". Advances in Meteorology 2016 (2016): 1–18. http://dx.doi.org/10.1155/2016/9059383.
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A subtropical squall line moved from Guangxi to Guangdong province in South China on 23-24 April 2007, which resulted in gale and heavy precipitation. The three-dimensional (3D) wind field of the squall line in its mature period was retrieved by Guangzhou-Shenzhen dual-Doppler data. The 3D conceptual model of this squall line was proposed. On the horizontal plane, the storm-relative front-to-rear inflow prevailed at the lower altitudes of the leading edge. The rear-to-front cold inflow in the stratiform region was observed below 3 km height, which enhanced the convergence in the convective region. At the middle altitudes of the squall line, the front-to-rear horizontal flow prevailed. Strong updrafts were observed at the lower and middle altitudes of the leading edge. Some convergence centers were located at the lower altitudes of the convective region. Furthermore, the storm-relative flow in the vertical cross-section perpendicular to the squall line was revealed. The front-to-rear warm flow extended from the surface to 7.5 km altitude at the leading edge. Above it, part of the front-to-rear inflow blew upward and then forward, and the other part of the inflow blew backward. The descending rear-to-front cold flow was only seen below 3 km height in the stratiform region.
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Smith, Andrea M., Greg M. McFarquhar, Robert M. Rauber, Joseph A. Grim, Michael S. Timlin, Brian F. Jewett y David P. Jorgensen. "Microphysical and Thermodynamic Structure and Evolution of the Trailing Stratiform Regions of Mesoscale Convective Systems during BAMEX. Part I: Observations". Monthly Weather Review 137, n.º 4 (1 de abril de 2009): 1165–85. http://dx.doi.org/10.1175/2008mwr2504.1.
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Abstract This study used airborne and ground-based radar and optical array probe data from the spiral descent flight patterns and horizontal flight legs of the NOAA P-3 aircraft in the trailing stratiform regions (TSRs) of mesoscale convective systems (MCSs) observed during the Bow Echo and Mesoscale Convective Vortex Experiment (BAMEX) to characterize microphysical and thermodynamic variations within the TSRs in the context of the following features: the transition zone, the notch region, the enhanced stratiform rain region, the rear anvil region, the front-to-rear flow, the rear-to-front flow, and the rear inflow jet axis. One spiral from the notch region, nine from the enhanced stratiform rain region, and two from the rear anvil region were analyzed along with numerous horizontal flight legs that traversed these zones. The spiral performed in the notch region on 29 June occurred early in the MCS life cycle and exhibited subsaturated conditions throughout its depth. The nine spirals performed within the enhanced stratiform rain region exhibited saturated conditions with respect to ice above and within the melting layer and subsaturated conditions below the melting layer. Spirals performed in the rear anvil region showed saturation until the base of the anvil, near −1°C, and subsaturation below. These data, together with analyses of total number concentration and the slope to gamma fits to size distributions, revealed that sublimation above the melting layer occurs early in the MCS life cycle but then reduces in importance as the environment behind the convective line is moistened from the top down. Evaporation below the melting layer was insufficient to attain saturation below the melting layer at any time or location within the MCS TSRs. Relative humidity was found to have a strong correlation to the component of wind parallel to the storm motion, especially within air flowing from front to rear.
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Chen, Keji, Xiaofei Pei, Guocheng Ma y Xuexun Guo. "Longitudinal/Lateral Stability Analysis of Vehicle Motion in the Nonlinear Region". Mathematical Problems in Engineering 2016 (2016): 1–15. http://dx.doi.org/10.1155/2016/3419108.
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We focus on the study of motion stability of vehicle nonlinear dynamics. The dynamic model combining with Burckhardt tire model is firstly derived. By phase portrait method, the vehicle stability differences of three cases, front wheels steering/four-wheel steering case, front/rear/four-wheel braking case, and high/low road friction case, are characterized. With the Jacobian matrix, the stable equilibrium point is found and stable areas are calculated out. Similarly, the stability boundaries corresponding to different working conditions are also captured. With vehicle braking or accelerating in the steering process, the relationship between front/rear wheel slippage and the stable area is examined. Comparing with current literatures, the research method and its results present the novelty and provide a guideline for new vehicle controller design.
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Harun, Zambri, Muhammad Syafiq, Mohd Rasidi Rasani, Shahrum Abdullah, Rozli Zulkifli, Wan Mohd Faizal Wan Mahmood, Mariyam Jameelah Ghazali et al. "Skin Friction Coefficient and Boundary Layer Trend on UKM Aster i-Bond". Applied Mechanics and Materials 629 (octubre de 2014): 450–55. http://dx.doi.org/10.4028/www.scientific.net/amm.629.450.
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This study concerns with aerodynamic drag on a passenger car. By using computational fluid dynamics (CFD) method, we found that values of skin friction coefficients for three different parts of the car: front, top and rear parts, are different. This study addresses three different basic possible flows around a car: favourable, zero and adverse pressure gradients. Generally, cars use approximately 20% of their engine power to overcome aerodynamic drag, which is generally proportional to the frontal area. The boundary layer at each position has been analyzed to ascertain the effect of wall shear stress on the car surface. It is found that the value of wall shear stress velocity is highest at the rear part, followed by front and top parts. Subsequently, it is shown that the front part has the thinnest viscous region despite not being the part with the highest local ambient velocity compared with the top and rear parts. Despite its supposed aerodynamic shape, the rear part of the car sees separation of flow and the total drag per unit area here is the largest, twice as large as front part and more than seven times larger than the top part.
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Lee, Bruce D., Catherine A. Finley y Timothy M. Samaras. "Surface Analysis near and within the Tipton, Kansas, Tornado on 29 May 2008". Monthly Weather Review 139, n.º 2 (1 de febrero de 2011): 370–86. http://dx.doi.org/10.1175/2010mwr3454.1.
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Abstract Data collected by a mesonet within the near-tornado environment and in the Tipton tornado on 29 May 2008 provided a rare opportunity to analyze rear-flank downdraft (RFD) outflow properties closely bounding a tornado and to characterize parcel thermodynamics being ingested into a tornado from the rear-flank downdraft. Parcels moving into the tornado on its right flank had very small negative buoyancy and considerable potential buoyancy. Measurements within and very near the tornado showed similar buoyancy characteristics to the storm inflow. Analyzed surface divergence and videographic evidence indicated that the RFD outflow just to the right and wrapping in front of the tornado was supported by parcels moving out of a narrow downdraft bordering the right flank of the tornado. Surface flow field analysis showed that parcels moved out of the downdraft-associated divergence region and into the right side of, as well as in front of, the tornado. An internal RFD surge boundary was positioned roughly 0.5 km in front of the eastern edge of the analyzed divergence region and implied downdraft. The broader RFD outflow thermodynamic characteristics were consistent with recent research with only small negative buoyancy and substantial potential buoyancy; however, convective inhibition was considerably higher than typically found in other tornadic cases. This latter characteristic was emblematic of the broader storm environment on this day. Parcels making up the RFD outflow originated from low-levels, consistent with recent findings for tornadic rear-flank downdrafts and in contrast to past historical indications for the rear-flank downdraft source region.
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Kirsanova, M. S., P. A. Boley, A. V. Moiseev, D. S. Wiebe y R. I. Uklein. "3D structure of the H ii region Sh2-235 from tunable-filter optical observations". Monthly Notices of the Royal Astronomical Society 497, n.º 1 (10 de julio de 2020): 1050–58. http://dx.doi.org/10.1093/mnras/staa2004.
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ABSTRACT We present observations of the H α, H β, [S ii] λλ6716, 6731 and [N ii] λ6583 emission lines in the galactic H ii region Sh2-235 with the Mapper of Narrow Galaxy Lines (MaNGaL), a tunable filter at the 1-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We show that the H ii region is obscured by neutral material with AV ≈ 2−4 mag. The area with the highest AV is situated to the south-west from the ionizing star and coincides with a maximum detected electron density of ≳300 cm−3. The combination of these results with archive AKARI far-infrared data allows us to estimate the contribution of the front and rear walls to the total column density of neutral material in S235 and explain the 3D structure of the region. The H ii region consist of a denser, more compact portion deeply embedded in the neutral medium and the less dense and obscured gas. The front and rear walls of the H ii region are inhomogeneous, with the material in the rear wall having a higher column density. We find a two-sided photodissociation region in the dense clump S235 East 1, illuminated by a UV field with G0 = 50−70 and 200 Habing units in the western and eastern parts, respectively.
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Kim, Jin Man, Minji Lee, Nury Kim y Won Do Heo. "Optogenetic toolkit reveals the role of Ca2+sparklets in coordinated cell migration". Proceedings of the National Academy of Sciences 113, n.º 21 (17 de mayo de 2016): 5952–57. http://dx.doi.org/10.1073/pnas.1518412113.
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Cell migration is controlled by various Ca2+signals. Local Ca2+signals, in particular, have been identified as versatile modulators of cell migration because of their spatiotemporal diversity. However, little is known about how local Ca2+signals coordinate between the front and rear regions in directionally migrating cells. Here, we elucidate the spatial role of local Ca2+signals in directed cell migration through combinatorial application of an optogenetic toolkit. An optically guided cell migration approach revealed the existence of Ca2+sparklets mediated by L-type voltage-dependent Ca2+channels in the rear part of migrating cells. Notably, we found that this locally concentrated Ca2+influx acts as an essential transducer in establishing a global front-to-rear increasing Ca2+gradient. This asymmetrical Ca2+gradient is crucial for maintaining front–rear morphological polarity by restricting spontaneous lamellipodia formation in the rear part of migrating cells. Collectively, our findings demonstrate a clear link between local Ca2+sparklets and front–rear coordination during directed cell migration.
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GARUCHAVA, D. P., I. G. MURUSIDZE, G. I. SURAMLISHVILI, N. L. TSINTSADZE y D. D. TSKHAKAYA. "Interaction of a non-symmetric powerful laser pulse with a plasma". Journal of Plasma Physics 59, n.º 1 (enero de 1998): 57–68. http://dx.doi.org/10.1017/s0022377897006107.
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The interaction of a powerful non-symmetric laser pulse with a plasma is studied. The non-symmetry is manifested in an abrupt cut-off of the rear edge of the laser pulse compared with its leading edge. At the same time, three qualitatively different regions are distinguished: the leading edge, the rear edge and the region behind the pulse, where it leaves a wake in the form of generated fields. An analytical solution has been found that defines the longitudinal accelerating field at the end of the rear edge. The results of numerical calculations confirm our physical point of view that the non-symmetry of the laser pulse increases the duration of the ion channel behind the front, thereby enhancing the focusing and effective acceleration of electron bunches.
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Olguin-Olguin, Adan, Anne Aalto, Benoît Maugis, Aleix Boquet-Pujadas, Dennis Hoffmann, Laura Ermlich, Timo Betz, Nir S. Gov, Michal Reichman-Fried y Erez Raz. "Chemokine-biased robust self-organizing polarization of migrating cells in vivo". Proceedings of the National Academy of Sciences 118, n.º 7 (11 de febrero de 2021): e2018480118. http://dx.doi.org/10.1073/pnas.2018480118.
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To study the mechanisms controlling front-rear polarity in migrating cells, we used zebrafish primordial germ cells (PGCs) as an in vivo model. We find that polarity of bleb-driven migrating cells can be initiated at the cell front, as manifested by actin accumulation at the future leading edge and myosin-dependent retrograde actin flow toward the other side of the cell. In such cases, the definition of the cell front, from which bleb-inhibiting proteins such as Ezrin are depleted, precedes the establishment of the cell rear, where those proteins accumulate. Conversely, following cell division, the accumulation of Ezrin at the cleavage plane is the first sign for cell polarity and this aspect of the cell becomes the cell back. Together, the antagonistic interactions between the cell front and back lead to a robust polarization of the cell. Furthermore, we show that chemokine signaling can bias the establishment of the front-rear axis of the cell, thereby guiding the migrating cells toward sites of higher levels of the attractant. We compare these results to a theoretical model according to which a critical value of actin treadmilling flow can initiate a positive feedback loop that leads to the generation of the front-rear axis and to stable cell polarization. Together, our in vivo findings and the mathematical model, provide an explanation for the observed nonoriented migration of primordial germ cells in the absence of the guidance cue, as well as for the directed migration toward the region where the gonad develops.
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Vicente-Manzanares, Miguel, Margaret A. Koach, Leanna Whitmore, Marcelo L. Lamers y Alan F. Horwitz. "Segregation and activation of myosin IIB creates a rear in migrating cells". Journal of Cell Biology 183, n.º 3 (27 de octubre de 2008): 543–54. http://dx.doi.org/10.1083/jcb.200806030.
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We have found that MLC-dependent activation of myosin IIB in migrating cells is required to form an extended rear, which coincides with increased directional migration. Activated myosin IIB localizes prominently at the cell rear and produces large, stable actin filament bundles and adhesions, which locally inhibit protrusion and define the morphology of the tail. Myosin IIA forms de novo filaments away from the myosin IIB–enriched center and back to form regions that support protrusion. The positioning and dynamics of myosin IIA and IIB depend on the self-assembly regions in their coiled-coil C terminus. COS7 and B16 melanoma cells lack myosin IIA and IIB, respectively; and show isoform-specific front-back polarity in migrating cells. These studies demonstrate the role of MLC activation and myosin isoforms in creating a cell rear, the segregation of isoforms during filament assembly and their differential effects on adhesion and protrusion, and a key role for the noncontractile region of the isoforms in determining their localization and function.
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Romashets, E., M. Vandas y S. Poedts. "Magnetic field disturbances in the sheath region of a super-sonic interplanetary magnetic cloud". Annales Geophysicae 26, n.º 10 (15 de octubre de 2008): 3153–58. http://dx.doi.org/10.5194/angeo-26-3153-2008.
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Abstract. It is well-known that interplanetary magnetic clouds can cause strong geomagnetic storms due to the high magnetic field magnitude in their interior, especially if there is a large negative Bz component present. In addition, the magnetic disturbances around such objects can play an important role in their "geo-effectiveness". On the other hand, the magnetic and flow fields in the CME sheath region in front of the body and in the rear of the cloud are important for understanding both the dynamics and the evolution of the interplanetary cloud. The "eventual" aim of this work is to calculate the magnetic field in this CME sheath region in order to evaluate the possible geo-efficiency of the cloud in terms of the maximum |Bz|-component in this region. In this paper we assess the potential of this approach by introducing a model with a simplified geometry. We describe the magnetic field between the CME shock surface and the cloud's boundary by means of a vector potential. We also apply our model and present the magnetic field distribution in the CME sheath region in front of the body and in the rear of the cloud formed after the event of 20 November 2003.
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KOPTELOVA, ANASTASIA S. "ARKHANGELSK DISTRICT OF VORONEZH REGION IN THE YEARS OF THE GREAT PATRIOTIC WAR". CASPIAN REGION: Politics, Economics, Culture 66, n.º 1 (2021): 24–29. http://dx.doi.org/10.21672/1818-510x-2021-66-1-024-029.
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Today, the study of the history of the Great Patriotic War is of interest both for professional historians and for those interested in Patriotic history, which, in turn, is due to a number of socio-political factors. At the same time, despite the wide interest of modern Russian society and a narrow circle of specialists in this period, there is a problem of subjective perception of the history of the Great Patriotic War. The purpose of the study is the Arkhangelsk district of the Voronezh region during the Great Patriotic War as a rear area. The scientific novelty of this article lies primarily in the fact that for the first time a description of the daily life of the Arkhangelsk district of the Voronezh region and its inhabitants during the Great Patriotic War is given. There are analyzed the activity and work of both enterprises and organizations and individual citizens in the rear. Brief biographical data of the workers of the rear of the Great Patriotic War, natives of the Arkhangelsk district of the Voronezh region are investigated, their memories are given. The article also mentions the situation of underage home front workers, their contribution to harvesting and digging trenches. The results of the study provide a broad insight into everyday life in the Soviet rear during the Great Patriotic Warю
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Johnson, M. C. y E. M. Greitzer. "Effects of Slotted Hub and Casing Treatments on Compressor Endwall Flow Fields". Journal of Turbomachinery 109, n.º 3 (1 de julio de 1987): 380–87. http://dx.doi.org/10.1115/1.3262117.
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An experimental investigation was carried out to examine the influence of a rotating slotted hub treatment on a compressor stator passage endwall. Detailed mapping of the three-dimensional unsteady velocity field near the hub was done for a smooth hub and a hub having axial skewed slots. With the smooth wall, the velocity measurements indicate that a large region of blockage occurs near the rear of the blade passage. This blockage is seen to be associated with the hub endwall rather than either the suction surface or the pressure surface of the blade. With axial skewed slots, the blockage is markedly decreased, the stalling flow coefficient is reduced, and the peak pressure rise greatly increased. Due to the axial (rear-to-front) flow in the slots, there is a region of fluid removal (from the endwall) near the rear of the passage and a strong fluid injection, or jet, near the front. The data appear to show that this flow removal is an important part of the effect on stall margin found with hub and casing treatment. Furthermore, the data indicate that it is the (dissipation of the) high velocities in the jet that is the prime source of the efficiency reduction associated with this treatment.
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Mion, Renildo Luiz, Virginia Pires Pereira, Webert Alan Sombra, Karla Lúcia Batista Araújo y Silvia Ferreira da Silva. "MECHANICAL PROPERTIES OF AN ALFISSOL SUBMITTED TO AGRICULTURAL MACHINERY TRAFFIC IN A SEMIARID REGION IN BRAZIL - DOI: 10.13083/1414-3984.v22n06a05". REVISTA ENGENHARIA NA AGRICULTURA - REVENG 22, n.º 6 (23 de diciembre de 2014): 543–51. http://dx.doi.org/10.13083/reveng.v22i6.412.
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The load carrying capacity of the soil can be determined from preconsolidation curves, being sensitive to the variation of loads and extremely sensitive to changes in soil moisture. For this study, the water content in soil was 2.50% and 10.58% for the layer from 0 to 0.15 m. Soil samples were collected before and after traffic with one and two passes of a tractor weighing 7100 kg, equipped with 14.4-24 R1 bias tires on the front with inflation pressure of 82.74 kPa and 18.9-34 R1 rear tires with inflation pressure of 96.53 kPa, and a tire ground contact area of 0.11 m2 and 0.13 respectively for the front and rear tires. The speed at the time of the pass for each treatment was 2.22 m s-1. Regardless of the soil water content, the load carrying capacity increases with the traffic of machines due to reduction of voids. Preconsolidation curves should be used with caution due to the use of samples for determining the points in saturated conditions, and when recommended for load-bearing capacity, unsaturated samples should be used.
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Mariskin, Oleg I. "Daily life of the population of the USSR during the Great Patriotic War 1941–1945: based on the materials of the Atyashevsky district of the Mordovian ASSR". Economic History 16, n.º 1 (3 de abril de 2020): 84–90. http://dx.doi.org/10.15507/2409-630x.048.016.202001.084-090.
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Introduction. The article explores the daily life of the rear region during the Great Patriotic War of 1941–1945. The workers of the Atyashevsky district of the Mordovian ASSR, like all Soviet people, stood up for the Fatherland. The Great Patriotic war made fundamental changes in the way of life of the home front. Women, children, and old men who replaced men gone to the front often worked around the clock and slept in their workplaces. Results and Discussion. During the war, many types of agricultural work were performed manually. In the rear, food shortages caused difficulties in supplying the population with food. It was no better to provide food for the families of front-line soldiers. Collective farmers and sole peasants began to pay personal land, since then the main source of food. The villagers grew many of the crops that were previously produced by farmers on arable land, but in much smaller amounts. Workers of the district led to the construction of fortifications – the Sursky defense line. Conclusion. The war is leaving the past, its participants, soldiers’ widows and mothers are still less alive, but the feat accomplished by the soldiers and workers of the rear during the years of the Great Patriotic War is immortal.
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Yu, Cheng-Ku y Chia-Lun Tsai. "Structural and Surface Features of Arc-Shaped Radar Echoes along an Outer Tropical Cyclone Rainband". Journal of the Atmospheric Sciences 70, n.º 1 (1 de enero de 2013): 56–72. http://dx.doi.org/10.1175/jas-d-12-090.1.
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Abstract This study uses ground-based dual-Doppler radar and surface observations to document the structural and surface features of the arc-shaped radar echoes (ASREs) evident along an outer rainband of Typhoon Longwang as it approached northern Taiwan on 1 October 2005. The particular aim of this study is to explore the possible distinction between the present case, previously documented tropical cyclone rainbands (TCRs), and squall lines. The dual-Doppler-derived fields show that the leading precipitation of the studied ASREs exhibited a convective nature with a sharp horizontal gradient of reflectivity and a significant vertical extent. The regions behind the leading convection were characterized by band-relative rear-to-front flow at low levels and were associated with a broader area of stratiform precipitation. The deep layer of front-to-rear flow extending from the surface to the upper troposphere was generally present ahead of the ASREs. This flow appears to be lifted upward at and immediately ahead of the leading edge of the low-level rear-to-front flow to form rearward-tilting updrafts. These airflow patterns are similar to those of the convective region of squall lines but differ fundamentally from those of previously documented TCRs that were located closer to the inner core of cyclones. The detailed analyses of surface fluctuations during the passage of one of the studied ASREs further show an abrupt pressure rise (2 mb), a temperature drop (4°C), and a pronounced deceleration of inflow air coincident with the leading heavy precipitation. The evaluation presented suggests that the convectively generated cold pool may be important in influencing the structures and propagation of the studied ASREs.
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Wang, Yu. "Numerical study of hydrodynamics and thermal characteristics of heat exchangers with delta winglets". Thermal Science 24, n.º 1 Part A (2020): 325–38. http://dx.doi.org/10.2298/tsci180330254w.
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The comprehensive performance of heat exchangers is represented by the maximum thermal transfer, the minimum pressure loss, and the smallest pumping power. In recent years, the application of longitudinal vortex generators is developed as an effective technique and important research topic, which could increase the heat transfer enhancement of compact heat exchangers. A 3-D CFD numerical simulation is successfully carried out on thermohydraulic characteristics of the fin-and-tube compact heat exchanger with new types of vortex generators. The effects of six different arrangement of delta winglets are studied, which are front-up-rear-down, front-down-rear-up, common-flow-up, and common-flow-down. In addition, there are also different direction of hole position in the same delta winglets arrangement. The investigation of thermal-hydraulic performance is conducted for Reynolds number in the range of 204-2034. The overall and local performance comparisons among the fin with delta winglets and the wavy fin are performed. Then, the comprehensive performance evaluation diagram was adopted to analyze the combined index point of thermal and flow. This study shows that the flow distinction between different fins has a profound influence on the thermal-hydrodynamic performance. The results reveal that the fin with delta winglets can considerably strengthen the thermal efficiency with a moderate pressure loss penalty. The computational results indicate that the average j-factor for the fin with delta wing-lets can be increased up to 41.9% over the baseline case and the corresponding f-factor decreased up to 19.5%. The combination property of front-up-rear-down are better the others at lower Reynolds number, and that of front-down-rear-up are better at higher Reynolds number. Compare with the traditional arrangement (common-flow-up and common-flow-down), The newly designed fin has great effectiveness and uniform performance in the local region.
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Garvin, J. L., R. Robb y S. A. Simon. "Spatial map of salts and saccharides on dog tongue". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 255, n.º 1 (1 de julio de 1988): R117—R122. http://dx.doi.org/10.1152/ajpregu.1988.255.1.r117.
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Front and rear regions of dog tongue were tested for spatial heterogeneity with respect to monovalent chloride salts (NaCl, KCl, and NH4Cl) and sweet tastants (sucrose, D-glucose, and L-glucose) by placing them in Ussing chambers where the open-circuit potential, Voc, and short-circuit current, Isc, were measured. The responses of Voc and Isc to 0.5 M NaCl were greater in the front of the tongue than in the rear, whereas the responses of Voc and Isc to 0.5 M sucrose were greater in the rear of the tongue than in the front. These results are similar to those of published neurophysiological measurements from the chorda tympani nerve and thalamus. These data suggest that the spatial heterogeneities seen in higher taste centers are present in the isolated lingual epithelium where primary taste transduction events occur.
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Vorontsov, Roman S. y Vladimir V. Korovin. "Archival Documents on the Impact of the Great Patriotic War on the State of the Sugar Industry Factories: Materials of the Kursk Region". Herald of an archivist, n.º 2 (2020): 578–89. http://dx.doi.org/10.28995/2073-0101-2020-2-578-589.
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The article draws on archival sources on the activities of regional authorities in regulation of economic relations under wartime conditions to discuss problems in organizing production activities of sugar enterprises of the Kursk region. Although there are some works on the history of the industrial production development during the Great Patriotic War on the all-Union, republican, and regional levels, which take into account all modern achievements of historical science and development of the source base, the impact of the war on the state of individual branches of food industry supplying the front and rear remains unexplored. The choice of the territorial frameworks of the study springs from several circumstances. Firstly, the Kursk region for a long time occupied a leading position in the RSFSR in the volume of products manufactured by sugar factories. Secondly, during the war, the territory of the region had the status of a front-line, occupied, front-line, and rear-line area, which had a significant impact on the specifics of all tasks related to production organization. The main source is archival documents on various aspects of management and production activities. The authors have identified documentary materials in the fonds of the Russian State Archives of Economics, the State Archives of the Kursk Region, and the State Archive of the Socio-Political History of the Kursk Region, that cover events and processes associated with the dynamics in the sugar industry of the Kursk region, one of the key sectors of regional wartime economy. They have analyzed the content of these documents and offered a general assessment of problems in functioning of the industry under extreme conditions. Of greatest information value on the said topic are materials from regional archives. Archival documents objectively reflect the situation in the food industry during the war. Their introduction into scientific use will contribute to a reliable reflection of the role of economic potential of the USSR in the defeat of Nazism.
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Strelnikov, Vladimir V. "Murmansk region, 1941 in the "Diary of war" by M.I. Starostin." Transaction Kola Science Centre 11, n.º 6-2020 (25 de diciembre de 2020): 153–63. http://dx.doi.org/10.37614/2307-5252.2020.6.19.012.
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The diary entries of the party leader of the war years -the first secretary of the Murmansk regional committee of the CPSU (b), Maxim Ivanovich Starostin, are considered. Special attention is paid tothe records reflecting the administrative and economic aspects of the regional leadership activities, so as military everyday life of the city Murmansk in 1941.The main problems that the regional administration dealt with at the initial stage of the military clash between Germany and the USSR are highlighted. The leadership was intensively and regularly engaged in mobilizing regional resources, starting in the fallof 1941. The most important issues that required constant attention of M. I. Starostin during this period were a) provision of food for civilians and military personnel, b) replenishment of weapons and ammunition, c) attraction of individual groups of workers, d) evacuation of industrial facilities and the population of the frontline territories. It is concluded that the source is of great value for studying the front-line territories during the Great Patriotic War, the organization of command and control in military conditions, the problems of interaction between regions, front and rear, as well as the role of the leader's personality.
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Tuzova, Olga Vladimirovna. "Regional musical culture management in 1939-1945 (on materials of the Volga Region)". Samara Journal of Science 6, n.º 1 (1 de marzo de 2017): 139–42. http://dx.doi.org/10.17816/snv201761212.
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The paper deals with some problems of musical institutions management in the Volga Region in 1939 1945 on the example of 8 musical cultural models of rear, frontal and front-line types: Kuibyshev, Ulyanovsk, Penza, Saratov, Engels, Kazan, Stalingrad, Astrakhan. The author reconstructs the structure and functional complex of the management component, describes the responsibilities of the commissioners of Performances and Repertoire Control Main Department at different levels and detects the role of the Communist party in the music management of the region. The author notes instability and incomplete correspondence of the administrative board in some models as a negative factor. A significant impact on musical culture management in the region provided emergency-revaluation processes: range of competencies and staff. Changes in the geography of governance structures affected the Stalingrad model of front type. Some actual data about the material provision of the management component are provided: departments placement and employees salaries. Structural complexity of administrative areas during 1939 1945 is stated. The author restores a number of regional culture managers names and their professional affiliation.
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Ramaniuk, Olga, Zuzana Klímová, Tomáš Groušl y Tomáš Vomastek. "Quantitative Phase Imaging of Spreading Fibroblasts Identifies the Role of Focal Adhesion Kinase in the Stabilization of the Cell Rear". Biomolecules 10, n.º 8 (22 de julio de 2020): 1089. http://dx.doi.org/10.3390/biom10081089.
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Cells attaching to the extracellular matrix spontaneously acquire front–rear polarity. This self-organization process comprises spatial activation of polarity signaling networks and the establishment of a protruding cell front and a non-protruding cell rear. Cell polarization also involves the reorganization of cell mass, notably the nucleus that is positioned at the cell rear. It remains unclear, however, how these processes are regulated. Here, using coherence-controlled holographic microscopy (CCHM) for non-invasive live-cell quantitative phase imaging (QPI), we examined the role of the focal adhesion kinase (FAK) and its interacting partner Rack1 in dry mass distribution in spreading Rat2 fibroblasts. We found that FAK-depleted cells adopt an elongated, bipolar phenotype with a high central body mass that gradually decreases toward the ends of the elongated processes. Further characterization of spreading cells showed that FAK-depleted cells are incapable of forming a stable rear; rather, they form two distally positioned protruding regions. Continuous protrusions at opposite sides results in an elongated cell shape. In contrast, Rack1-depleted cells are round and large with the cell mass sharply dropping from the nuclear area towards the basal side. We propose that FAK and Rack1 act differently yet coordinately to establish front–rear polarity in spreading cells.
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Frame, Jeffrey y Paul Markowski. "Dynamical Influences of Anvil Shading on Simulated Supercell Thunderstorms". Monthly Weather Review 141, n.º 8 (25 de julio de 2013): 2802–20. http://dx.doi.org/10.1175/mwr-d-12-00146.1.
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Abstract Numerical simulations of supercell thunderstorms including parameterized radiative transfer and surface fluxes are performed using the Advanced Regional Prediction System (ARPS) model to investigate how low-level air temperature deficits within anvil shadows affect the simulated storms. The maximum temperature deficits within the modeled cloud shadows are 1.5–2.0 K, which is only about half that previously observed. Within the shadows, the loss of strong solar heating cools and stabilizes the near-surface layer, which suppresses vertical mixing and modifies the near-surface vertical wind shear. In a case of a stationary storm, the enhanced easterly shear present beneath the anvil leads to a thinning of the outflow layer and corresponding acceleration of the rear-flank gust front far ahead of the overlying updraft, weakening the low-level mesocyclone. It is further shown that the direct absorption and emission of radiation by clouds does not significantly affect the simulated supercells. Varying the time of day of model initialization does not prevent the simulated storms from weakening. This behavior is mirrored for storms that slowly move along the major axis of the anvil shadow. If the rear-flank gust front moves into the anvil shadow and the updraft moves normal to the shadow (i.e., northward movement of the updraft), cyclic periods of intensification and decay can result, although this result is likely highly dependent on the storm-relative wind profile. If the gust front does not advance into the shaded region (i.e., southward movement), or if the storm moves rapidly, the storm is relatively unaffected by anvil shading because the rear-flank gust front speed and outflow depth remain relatively unchanged.
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Kaasik, Peeter. "Hävituspataljonidest Eestis 1941. aasta sõjasuvel [Abstract: The Destruction Battalions in Estonia in the Summer War of 1941]". Ajalooline Ajakiri. The Estonian Historical Journal 167, n.º 1 (31 de diciembre de 2019): 3–36. http://dx.doi.org/10.12697/aa.2019.1.01.
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Abstract: The Destruction Battalions in Estonia in the Summer War of 1941
A state of war was declared in the western regions of the Soviet Union on 22 June 1941. This did not in any case mean only purely military operations. The safeguarding of security in the rear was considered extremely important. On 25 June 1941, the Union-wide Communist Party (CPSU) Central Committee Politburo adopted the decision ‘On the tasks in the rear of front-line forces’, which placed all agencies and units of the People’s Commissariat for Internal Affairs and State Security (NKVD and NKGB) under the command of the commanders of rear defence of the front lines. The following was prescribed as the more general tasks of rear defence: maintenance of law and order in the rear and on roads; the capture of deserters and ‘disorganisers of the rear’; protection of communications; the organisation of evacuations and the transportation of supplies; the destruction of saboteurs. Since rebellion against Soviet rule also began in parallel with combat action in many regions (primarily in regions that the Soviet Union occupied and annexed in 1939/1940), then combat against the so-called internal enemy became the primary task of rear defence units in the vicinity of the front in many areas. Thirdly, rear defence units were assigned the task of destroying all property of any value that could not be removed from the region of the front in the event of possible retreat.
At the same time, all communications of military importance were to be destroyed in the course of retreat. NKVD internal forces and border guard forces on the one hand, and irregular people’s defence units (destruction battalions, workers’ regiments, people’s defence divisions, etc.) formed locally in the summer of 1941 on the other hand were to bear the brunt of this action. The various irregular people’s defence units were on the one hand supposed to be manifestations of ‘nationwide struggle’ deriving from ideology; on the other hand, the need for an improvised territorial defence force was due to pragmatic needs that made it possible to skip many of the formalities associated with mobilisation, transport, formation and supply. At the same time, the possibilities for utilising these units were also considerably more flexible. The formation and utilisation of the ‘people’s defence force’ varied from region to region. The destruction battalions that were formed in the Estonian SSR are considered illustratively in this article.
As elsewhere in areas in the vicinity of the front, the formation of destruction battalions began in the Estonian SSR at the end of June, 1941. The ‘Estonian SSR operative group of destruction battalions’ was established for their formation and command at the NKVD Baltic Border Guard District headquarters. At the start of July, this operative group was placed under the command of the assistant responsible for rear area defence of the commander of the 8th Army, which had retreated into Estonia.
The destruction battalions did not have any definite composition of personnel. Although the self-evidence of patriotism was stressed, in reality the battalions were manned in Estonia by way of ‘Party mobilisation’. If a person was a member or candidate member of the CPSU or the communist youth organisation and did not have any other administrative duties, joining the destruction battalions was in essence mandatory. Generally speaking, this obligation also applied to the employees of other Soviet institutions as well.
The operations of destruction battalions in Estonia can conditionally be divided into three periods: 1) combat against the armed resistance movement before the arrival of German forces; 2) the direct employment of destruction battalions in military assignments alongside securing the rear area; 3) the deployment of destruction battalions and regiments formed out of them at the front in combat against regular Wehrmacht units.
This periodisation is nevertheless conditional. It is rather difficult to present temporal frames of reference more precisely because the actions and composition of different units varied depending on the situation at the front and they also do not match temporally. While battalions were initially formed in the counties and in the cities of Tallinn and Narva, later on units were disbanded and combined, and new additional units were also formed. In total, over 20 such units operated in Estonia (in addition to several more Latvian destruction units that had retreated into Estonia) in the summer war of 1941. Over 6,000 fighters were entered in the lists of the Estonian SSR militia companies, destruction battalions and workers’ regiments. These in turn were divided up according to specific assignments: some went on raids and later fought at the front line as part of the Red Army; others were part of the armed units guarding certain industrial enterprises or Soviet institutions, or provided security for communications of military importance (railroads, bridges, communications lines, and other such sites). Third, there was a large group that was formally connected to destruction battalions because they were tied mainly to other military-administrative duties (the organisation of evacuation, fortification works, mobilisation of horses and motor vehicles, future partisan warfare, and other such duties).
As the name ‘destruction battalion’ already says, these units were initially supposed to be used mainly in combatting saboteurs, spies and local ‘bandits’, and in carrying out ‘scorched earth tactics’. Yet as we can already see from the previous periodization, the role of destruction battalions in Estonia already became blurred at the start of July, 1941. Since the front was breached in many places, some units that were completely unprepared for it were quickly sent to the front to plug the holes. The Southern Estonian destruction battalions that had retreated in the direction of Narva fell apart, disintegrating into isolated troops that retreated together with civilians who wanted to evacuate. Other units were incorporated into the Red Army in Northern Tartu County in the latter half of July, and most of them were cut off there in a pocket. In August, two companies were formed in Harju County and Narva out of the remnants of the destruction battalions, and were already utilised directly as front-line units.
In conclusion it can be said that while the destruction battalions that operated in Estonia initially were indeed a rather effective force for a short time in the fight against armed resistance, their utilisation in front-line combat not only had negligible effect, it was also rather short-sighted in terms of Soviet rule because it resulted in the destruction of a large proportion of the cadre that was trustworthy in the eyes of the Soviet regime, and this cadre was already quite modest in numbers to begin with. A large proportion of the fighters of the destruction battalions left behind in the rear met their end in the course of vigilante justice in the summer war of 1941. And secondly, since the Germans did not count the members of the destruction battalions as soldiers, the status of prisoners of war did not extend to them, and many of them who were taken prisoner were shot on the spot or were executed at a later time as ‘active communists’.
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Yam, Patricia T., Cyrus A. Wilson, Lin Ji, Benedict Hebert, Erin L. Barnhart, Natalie A. Dye, Paul W. Wiseman, Gaudenz Danuser y Julie A. Theriot. "Actin–myosin network reorganization breaks symmetry at the cell rear to spontaneously initiate polarized cell motility". Journal of Cell Biology 178, n.º 7 (24 de septiembre de 2007): 1207–21. http://dx.doi.org/10.1083/jcb.200706012.
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We have analyzed the spontaneous symmetry breaking and initiation of actin-based motility in keratocytes (fish epithelial cells). In stationary keratocytes, the actin network flow was inwards and radially symmetric. Immediately before motility initiation, the actin network flow increased at the prospective cell rear and reoriented in the perinuclear region, aligning with the prospective axis of movement. Changes in actin network flow at the cell front were detectable only after cell polarization. Inhibition of myosin II or Rho kinase disrupted actin network organization and flow in the perinuclear region and decreased the motility initiation frequency, whereas increasing myosin II activity with calyculin A increased the motility initiation frequency. Local stimulation of myosin activity in stationary cells by the local application of calyculin A induced directed motility initiation away from the site of stimulation. Together, these results indicate that large-scale actin–myosin network reorganization and contractility at the cell rear initiate spontaneous symmetry breaking and polarized motility of keratocytes.
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Liu, Quan Ming. "Study on Numerical Simulation of Fully Mechanized Top Coal’s Caving Property of Tang Gong Ta Coal Mine". Advanced Materials Research 1094 (marzo de 2015): 410–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1094.410.
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Using numerical simulation method,fully mechanized top coal’s caving property of Tang gong ta coal mine was studied.The results show at primary mining period of fully mechanized working face, there were stress concentration regions at the front and rear of coal wall,but it was not distinct in the front and top coal’s caving property was not ideal.When it advanced to 84m of the working face,there would be obvious peak stress at the front and rear of coal wall. It accelerated top coal’s caving.When it advanced to 140m of the working face,top coal was caved with coal mining.Finally it was proved on the scene. The results of the study in fully mechanized mining’s safety and efficiency has some guiding role.
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Li, Han Yang, Ying Dai y Xiao Fei Lyu. "Application of Carbon Fiber Reinforced Composites on Lightweight Design of Articulated Platform". Materials Science Forum 921 (mayo de 2018): 85–90. http://dx.doi.org/10.4028/www.scientific.net/msf.921.85.
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For the purpose of weight saving, the heavy metal articulated platform, which is used in Bus Rapid Transit (BRT) vehicles to connect the front and rear compartments, is replaced with carbon fiber composite material. Composites articulated plates are designed based on the requirements of shape, size, positioning, connection and load of steel articulated platform. Optimization design is applied to high stress region in the articulated plates to provide references for the improvement and lightweight design of the articulated platform.
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BORAZJANI, IMAN y FOTIS SOTIROPOULOS. "Vortex-induced vibrations of two cylinders in tandem arrangement in the proximity–wake interference region". Journal of Fluid Mechanics 621 (12 de febrero de 2009): 321–64. http://dx.doi.org/10.1017/s0022112008004850.
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We investigate numerically vortex-induced vibrations (VIV) of two identical two-dimensional elastically mounted cylinders in tandem in the proximity–wake interference regime at Reynolds number Re = 200 for systems having both one (transverse vibrations) and two (transverse and in-line) degrees of freedom (1-DOF and 2-DOF, respectively). For the 1-DOF system the computed results are in good qualitative agreement with available experiments at higher Reynolds numbers. Similar to these experiments our simulations reveal: (1) larger amplitudes of motion and a wider lock-in region for the tandem arrangement when compared with an isolated cylinder; (2) that at low reduced velocities the vibration amplitude of the front cylinder exceeds that of the rear cylinder; and (3) that above a threshold reduced velocity, large-amplitude VIV are excited for the rear cylinder with amplitudes significantly larger than those of the front cylinder. By analysing the simulated flow patterns we identify the VIV excitation mechanisms that lead to such complex responses and elucidate the near-wake vorticity dynamics and vortex-shedding modes excited in each case. We show that at low reduced velocities vortex shedding provides the initial excitation mechanism, which gives rise to a vertical separation between the two cylinders. When this vertical separation exceeds one cylinder diameter, however, a significant portion of the incoming flow is able to pass through the gap between the two cylinders and the gap-flow mechanism starts to dominate the VIV dynamics. The gap flow is able to periodically force either the top or the bottom shear layer of the front cylinder into the gap region, setting off a series of very complex vortex-to-vortex and vortex-to-cylinder interactions, which induces pressure gradients that result in a large oscillatory force in phase with the vortex shedding and lead to the experimentally observed larger vibration amplitudes. When the vortex shedding is the dominant mechanism the front cylinder vibration amplitude is larger than that of the rear cylinder. The reversing of this trend above a threshold reduced velocity is associated with the onset of the gap flow. The important role of the gap flow is further illustrated via a series of simulations for the 2-DOF system. We show that when the gap-flow mechanism is triggered, the 2-DOF system can develop and sustain large VIV amplitudes comparable to those observed in the corresponding (same reduced velocity) 1-DOF system. For sufficiently high reduced velocities, however, the two cylinders in the 2-DOF system approach each other, thus significantly reducing the size of the gap region. In such cases the gap flow is entirely eliminated, and the two cylinders vibrate together as a single body with vibration amplitudes up to 50% lower than the amplitudes of the corresponding 1-DOF in which the gap flow is active. Three-dimensional simulations are also carried out to examine the adequacy of two-dimensional simulations for describing the dynamic response of the tandem system at Re = 200. It is shown that even though the wake transitions to a weakly three-dimensional state when the gap flow is active, the three-dimensional modes are too weak to affect the dynamic response of the system, which is found to be identical to that obtained from the two-dimensional computations.
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Gao, Guangjun, Yan Zhang, Fei Xie, Jie Zhang, Kan He, Jiabin Wang y Yani Zhang. "Numerical study on the anti-snow performance of deflectors in the bogie region of a high-speed train using the discrete phase model". Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 233, n.º 2 (3 de julio de 2018): 141–59. http://dx.doi.org/10.1177/0954409718785290.
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In this paper, the three-dimensional unsteady Reynolds-averaged Navier-Stokes equations with an RNG double-equation turbulence model and a discrete phase model were used for the investigation of snow accumulation on the bogie of a high-speed train. Two kinds of deflector plates, one installed at the front end and the other at the rear end of the bogie, were proposed to reduce snow accumulation. The accuracy of the CFD methodology was validated against wind tunnel tests. The results showed that high-speed air will impact the plates where snow particles get accumulated. The snow covering on the bogie rarely drifts back into the bogie region with air. The amount of accumulating snow in the optimum models is reduced by 50.58% on average as compared to those in the original models. At the rear end of the bogie, the inclined deflector plate reduced snow accumulation by up to 10.91% compared to the vertical deflector plate.
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Astashov, A. B. "MOBILIZATION AND SANITATION AT THE RUSSIAN ARMY HOME FRONT IN 1914–1918: SOCIO-ECOLOGICAL ANALYSIS". Вестник Пермского университета. История, n.º 2(53) (2021): 27–37. http://dx.doi.org/10.17072/2219-3111-2021-2-27-37.
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Written on the basis of archival sources drawn for the first time, the article is devoted to the problem of changing the sanitary and ecological conditions of the theatre of military operations at the Russian front during the First World War. The aim of the article is to analyze the sanitary and hygienic state of the theatre of military operations on the western outskirts of Russia during the First World War and the factors of its deterioration; to evaluate the effectiveness of combating the negative aspects of the sanitary state of the front-line territory; to identify the actual environmental practices of the front-line territory and their interrelation with the social aspects of the struggle for the improvement of the territory in conditions of total war. The focus is on the pre-war sanitary situation in the western region of Russia, reflecting its cultural and socio-political peculiarities, its exacerbation during the war and mobilization, as well as sanitary and hygienic measures taken both in eliminating epidemics of contagious diseases and in "sanitating" the front-line territory. The issue is considered in the light of total war, which formed a unified, front and rear, landscape of sanitary hazards. Attention is paid to the activities of society, bureaucracy and military commanders, who generally succeeded in transforming the belligerent landscape and localizing the spread of disease. The technical activities of the engineering and sanitary services of the front and rear are described in detail. The author concludes that the Great War was an important impulse and frontier in solving the problem of improving the ecological condition of Russia's western outskirts. During the war, the belligerent landscape was transformed into an anthropogenic landscape, becoming the basis for the area's future infrastructure in terms of sanitation and hygiene
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Chang, Wei-Yu, Wen-Chau Lee y Yu-Chieng Liou. "The Kinematic and Microphysical Characteristics and Associated Precipitation Efficiency of Subtropical Convection during SoWMEX/TiMREX". Monthly Weather Review 143, n.º 1 (1 de enero de 2015): 317–40. http://dx.doi.org/10.1175/mwr-d-14-00081.1.
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Abstract Dual-Doppler, polarimetric radar observations and precipitation efficiency (PE) calculations are used to analyze subtropical heavy rainfall events that occurred in southern Taiwan from 14 to 17 June 2008 during the Southwest Monsoon Experiment/Terrain-Influenced Monsoon Rainfall Experiment (SoWMEX/TiMREX) field campaign. Two different periods of distinct precipitation systems with diverse kinematic and microphysical characteristics were investigated: 1) prefrontal squall line (PFSL) and 2) southwesterly monsoon mesoscale convective system (SWMCS). The PFSL was accompanied by a low-level front-to-rear inflow and pronounced vertical wind shear. In contrast, the SWMCS had a low-level southwesterly rear-to-front flow with a uniform vertical wind field. The PFSL (SWMCS) contained high (low) lightning frequency associated with strong (moderate) updrafts and intense graupel–rain/graupel–small hail mixing (more snow and less graupel water content) above the freezing level. It is postulated that the reduced vertical wind shear and enhanced accretional growth of rain by high liquid water content at low levels in the SWMCS helped produce rainfall more efficiently (53.1%). On the contrary, the deeper convection of the PFSL had lower PE (45.0%) associated with the evaporative loss of rain and the upstream transport of liquid water to form larger stratiform regions. By studying these two events, the dependence of PE on the environmental and microphysical factors of subtropical heavy precipitation systems are investigated by observational data for the first time. Overall, the PE of the convective precipitation region (47.9%) from 14 to 17 June is similar to past studies of convective precipitation in tropical regions.
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Kiselev, L. Yu, R. A. Kamalov, M. Yu Borisov, N. A. Fedoseeva y Z. S. Sanova. "Modern technologies of robotized cowing milk". Rossiiskaia selskokhoziaistvennaia nauka, n.º 3 (24 de junio de 2019): 54–57. http://dx.doi.org/10.31857/s2500-26272019354-57.
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The studies were conducted in the conditions of LLC “Milk Group” of Sukhinichsky district of Kaluga region. The object of research is robotic milking machines, Swedish breed cows and Danish red breeds. Equality of development of the front and rear lobes, the udder index, the average milk flow rate and the frequency of delivery can be achieved only with long-term selection by type, good severity of signs of milkiness. Based on the selection of cows for milking on a robotized milking plant, the following requirements were put forward: high milk productivity and milk yield, tightly attached udder, nipples of the same size, the lower point of which should not be below 33 cm from the floor level, the minimum distance between the rear nipples in 3 cm, between the front nipples - 12.5 - 30 cm, the thickness of the nipples in the range of 1.5-3.5 cm, the rear nipples should be located 3 cm lower than the lower part of the udder, the minimum distance between the front and rear These udder teats - 7 cm, an angle of deviation from vertical teats should not exceed 30 °. The main reasons for the insignificant loss of milk during robotic milking are the milking of cows that do not have a full-fledged milk-giving reflex or the reflex was inhibited at the beginning of the milking of milk with a delay in putting the teat on the teats of the udder. The size of one-time milk yield, with the exception of the program indicators of this restriction on the milk yield, is determined by the frequency of effective visits to the robot (i.e., the multiplicity of milking during the day). In robotic milking, the frequency of milkings varies by day periods relatively little and drops to a minimum only in the second half of the night, in our opinion, due to the relatively late distribution of feed mixtures. It is also noted that cows of all ages have the same number of milkings on a robotized unit within 2 times.
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Balahonova, Maria Andreevna y Vladimir Sergeevich Okolotin. "Organisation of the educational process and scientific activity at Ivanovo Institute of Chemical Technology in 1941–1943". Vestnik of Kostroma State University 27, n.º 2 (28 de junio de 2021): 70–75. http://dx.doi.org/10.34216/1998-0817-2021-27-2-70-75.
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World War II posed new and complex challenges for the higher education system. It was necessary not only to preserve the system of training personnel for the national economy of the USSR, but also to focus on the development of the new materials necessary for the front and the rear. Ivanovo Chemical Technology Institute (ICTI) took a worthy place in this process. This article is devoted to the activities of the ICTI in 1941–1943, its role in the training personnel for the chemical plants, in the development of the dyes for the textile industry, in the manufacture of Molotov cocktails in the most difficult military conditions in the fall of 1941, etc. In addition, we examine the problems of the organising the educational process, the participation of the students in the procurement of fuel, the harvesting, the work at industrial enterprises. The information presented in the article about the labour heroism of the students and the scientists of the institute, strengthens the general knowledge about the contribution of the ICTI to meeting the needs of the front and the rear in 1941–1943. In the article we use the documents of State Archive of Ivanovo Region, introduced into scientific circulation for the first time, which gives it a special novelty, as well as sources of personal origin, which are the memories of the students of the ICTI during the war years which make it the most interesting to read.
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Pathak, Aditya, Ganesh Sethuraman, Sebastian Krapf, Aybike Ongel y Markus Lienkamp. "Exploration of Optimal Powertrain Design Using Realistic Load Profiles". World Electric Vehicle Journal 10, n.º 3 (15 de septiembre de 2019): 56. http://dx.doi.org/10.3390/wevj10030056.
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The electrification of bus-based public transportation contributes to the goal of reducing the adverse environmental impacts caused by urban transportation. However, the penetration of electric vehicles has been slow due to their lower vehicle range and total costs in comparison to vehicles driven by internal combustion engines. By improving the powertrain efficiency, the total costs can be reduced for the same vehicle range. Therefore, this paper proposes a holistic design exploration approach to investigate and identify the optimal powertrain concept for electric city buses based on the component costs and energy consumption costs. The load profiles of speed, slope, and passenger occupancy profiles are derived for a selected bus route in Singapore, which is used in a powertrain design exploration for a 30-passenger vehicle. Six different powertrain architectures are analyzed, together with single and multi-speed gearbox configurations, to identify the optimal powertrain architecture and the resulting component sizes. The powertrain configurations are further analyzed in terms of their influence on the vehicle characteristics and total costs. Multi-motor configurations were found to have better vehicle characteristics and lower total costs in comparison to single rear motor configurations. Concepts with motors on the front and a rear axle could shift the load points to a higher efficiency region, resulting in lower energy consumption and energy costs. The optimal powertrain concept was a fixed-speed two-motor configuration, with a booster motor on the front axle and a motor on the rear axle.
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Sugawara, Michiko, Hiromi Miyoshi, Takuya Miura, Hiroto Tanaka, Ken-ichi Tsubota y Hao Liu. "Dynamics of Actin Stress Fibers and Focal Adhesions during Slow Migration in Swiss 3T3 Fibroblasts: Intracellular Mechanism of Cell Turning". BioMed Research International 2016 (2016): 1–16. http://dx.doi.org/10.1155/2016/5749749.
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To understand the mechanism regulating the spontaneous change in polarity that leads to cell turning, we quantitatively analyzed the dynamics of focal adhesions (FAs) coupling with the self-assembling actin cytoskeletal structure in Swiss 3T3 fibroblasts. Fluorescent images were acquired from cells expressing GFP-actin and RFP-zyxin by laser confocal microscopy. On the basis of the maximum area, duration, and relocation distance of FAs extracted from the RFP-zyxin images, the cells could be divided into 3 regions: the front region, intermediate lateral region, and rear region. In the intermediate lateral region, FAs appeared close to the leading edge and were stabilized gradually as its area increased. Simultaneously, bundled actin stress fibers (SFs) were observed vertically from the positions of these FAs, and they connected to the other SFs parallel to the leading edge. Finally, these connecting SFs fused to form a single SF with matured FAs at both ends. This change in SF organization with cell retraction in the first cycle of migration followed by a newly formed protrusion in the next cycle is assumed to lead to cell turning in migrating Swiss 3T3 fibroblasts.
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Liskin, I., D. Mironov, S. Sidorov y I. Afonina. "Return bit for ploughing tools". Sel'skohozjajstvennaja tehnika: obsluzhivanie i remont (Agricultural Machinery: Service and Repair), n.º 2 (1 de febrero de 2020): 12–15. http://dx.doi.org/10.33920/sel-10-2002-02.
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Plough working elements performing formation cutting are the most loaded important parts, on which quality and economic indicators of ploughing depend. In terms of wear capacity, the difference for certain types of soils in Russia can range from 5 to 15 times. Developed and carried out tests of lemechs with a new, unparalleled in the world practice overhead return bit. Determination of the optimal ratio of the thickness of the cutting edge on the blade part of the front and rear side when installing the blade bit. Bits were made in which the leading edge (initial at operation) had a constant value of 4±2 mm. The rear edge had an optimal value of 6 mm from the experiments. The results of the tests showed that on the most common loam soils in the central regions of Russia, the optimal thickness value is the rear cutting edge, which turns the front edge 1.5–1.7 times. It was found that the cutting edge of the blade on the rear side when ploughing loam soils should exceed the leading edge 1.5–1.7 times in the initial period of operation and be 6–7 mm.
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Xia, Ning, Mao Sen Cao y Qing Wen Ren. "Experimental Study on Bonding Mechanism between Corroded Bolts and Grout". Key Engineering Materials 345-346 (agosto de 2007): 1063–66. http://dx.doi.org/10.4028/www.scientific.net/kem.345-346.1063.
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In this study, an experiment program is presented to study the bonding mechanism between corroded bolts and grout and in particular the influence on bonding behavior in terms of different corrosion sections along anchor. With respect to four groups of manufactured bolt specimens, the noncorroded and the corroded, respectively, on the front, middle and rear section along anchor, a pullout test is conducted to reveal the relationship between load and loading-end slip and to investigate the bond-stress distribution characterization along full anchor. Experimental results show that corrosion product, acting as lubricating effect at the interface between bolts and grout, can result in the degradation of bonding mechanical behavior. Meanwhile, corrosion on different sections along anchor has a different effect on the anchorage capacity of bolts. Especially, corrosion on the front section induces the greatest decrease of anchorage capacity of bolts. Thus, it is concluded that the front section along anchor is the key region affecting the bonding mechanical behavior between bolts and grout.
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van der Stoep, N., A. Serino, A. Farnè, M. Di Luca y C. Spence. "Depth: the Forgotten Dimension in Multisensory Research". Multisensory Research 29, n.º 6-7 (2016): 493–524. http://dx.doi.org/10.1163/22134808-00002525.
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The last quarter of a century has seen a dramatic rise of interest in the spatial constraints on multisensory integration. However, until recently, the majority of this research has investigated integration in the space directly in front of the observer. The space around us, however, extends in three spatial dimensions in the front and to the rear beyond such a limited area. The question to be addressed in this review concerns whether multisensory integration operates according to the same rules throughout the whole of three-dimensional space. The results reviewed here not only show that the space around us seems to be divided into distinct functional regions, but they also suggest that multisensory interactions are modulated by the region of space in which stimuli happen to be presented. We highlight a number of key limitations with previous research in this area, including: (1) The focus on only a very narrow region of two-dimensional space in front of the observer; (2) the use of static stimuli in most research; (3) the study of observers who themselves have been mostly static; and (4) the study of isolated observers. All of these factors may change the way in which the senses interact at any given distance, as can the emotional state/personality of the observer. In summarizing these salient issues, we hope to encourage researchers to consider these factors in their own research in order to gain a better understanding of the spatial constraints on multisensory integration as they affect us in our everyday life.
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Li, Guang-Xin, Ming-Bo Sun, Yi-Xin Yang, Tai-Yu Wang y Yuan Liu. "Spatial structural characteristics of a combustion flow field in an ethylene-fueled supersonic combustor with a rear-wall-expansion cavity". Modern Physics Letters B 34, n.º 18 (23 de junio de 2020): 2050208. http://dx.doi.org/10.1142/s0217984920502085.
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A hybrid large eddy simulation (LES)/assumed subgrid probability density function (PDF) closure model was employed to investigate the structural characteristics of the combustion flow field in an ethylene-fueled supersonic combustor with a rear-wall-expansion cavity. The wall pressure distribution from numerical simulation was compared with experimental data, and the numerical results are in good agreement with the experimental data. The spatial distribution characteristics of combustion heat release in the flow field are obtained from the simulation results. The reaction heat release zone is mainly distributed in the cavity. The cavity shear layer forms a concentrated reaction zone that produces a large amount of chemical heat release, thus further maintaining local stable combustion and forming a flame base. The front part of the cavity shear layer has the highest temperature in the whole flow field. There is still excess fuel reaching the cavity rear wall and producing a certain intensity of reaction. In addition, a dispersed small flame intermittently forms in the downstream near-wall region. The premixed combustion mode dominates the cavity recirculation zone, while the combustion in the downstream region evidently shows a non-premixed mode.
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Misiorowski, Matthew P., Farhan S. Gandhi y Assad A. Oberai. "Computational Analysis and Flow Physics of a Ducted Rotor in Edgewise Flight". Journal of the American Helicopter Society 64, n.º 4 (1 de octubre de 2019): 1–14. http://dx.doi.org/10.4050/jahs.64.042004.
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This study examines the performance of the ducted rotor in hover and edgewise flight conditions. The flow over a threedimensional model of a ducted rotor was simulated using the Spalart–Allmaras Reynolds-averaged Navier–Stokes model implemented in a stabilized finite element method. A sliding mesh was used to conveniently account for the large-scale motion associated with rotor revolutions. The simulation results were analyzed to understand the flow physics and quantify the contributions of the rotor and various sections of the duct interior surfaces on the total aerodynamic forces (thrust, drag, and side force) and moments (pitching and rolling). In edgewise flight, freestream flow separates off the front of the duct inlet, causing a region of recirculating flow and upwash in the rotor plane. The upwash region biases rotor thrust production to the front of the disk. The swirl velocity further biases the region of flow separation over the inlet and upwash at the front of the rotor toward the retreating side of the disk. The shift of thrust production on the rotor and duct toward the front produces a strong nose-up pitching moment on the ducted rotor. The rear of the diffuser is a significant contributor to the total drag; this force includes a nose-down pitch moment, which partially negates the moment from the duct inlet. The rotor is the primary source of vertical vibratory forces as well as vibratory pitching and rolling moments. The small tip clearance of the rotor causes a local interaction between the blade tip and duct that is the dominant contributor to in-plane vibratory forces on the ducted rotor.
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Karstens, Christopher D., Timothy M. Samaras, Bruce D. Lee, William A. Gallus y Catherine A. Finley. "Near-Ground Pressure and Wind Measurements in Tornadoes*". Monthly Weather Review 138, n.º 7 (1 de julio de 2010): 2570–88. http://dx.doi.org/10.1175/2010mwr3201.1.
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Abstract Since the spring of 2002, tornadoes were sampled on nine occasions using Hardened In-Situ Tornado Pressure Recorder probes, video probes, and mobile mesonet instrumentation. This study describes pressure and, in some cases, velocity data obtained from these intercepts. In seven of these events, the intercepted tornadoes were within the radar-indicated or visually identified location of the supercell low-level mesocyclone. In the remaining two cases, the intercepted tornadoes occurred outside of this region and were located along either the rear-flank downdraft gust front or an internal rear-flank downdraft surge boundary. The pressure traces, sometimes augmented with videography, suggest that vortex structures ranged from single-cell to two-cell, quite similar to the swirl-ratio-dependent continuum of vortex structures shown in laboratory and numerical simulations. Although near-ground tornado observations are quite rare, the number of contemporary tornado measurements now available permits a comparative range of observed pressure deficits for a wide variety of tornado sizes and intensities to be presented.
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TRUONG, QUOC BAO, VAN HUY PHAM y BYUNG RYONG LEE. "NEW VEHICLE DETECTION ALGORITHM USING SYMMETRY SEARCH AND GA-BASED SVM". International Journal of Pattern Recognition and Artificial Intelligence 27, n.º 02 (marzo de 2013): 1355003. http://dx.doi.org/10.1142/s0218001413550033.
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In this paper, we present a two-stage vision-based approach to detect front and rear vehicle views in road scene images. The first stage is hypothesis generation (HG), in which potential vehicles are hypothesized. During the HG step, we use a vertical, horizontal edge map, and different colors between road background and the lower part of vehicle to determine the bottom position of the vehicle. Next, we apply vertical symmetry axis detection into contour edge images to build the potential regions where vehicles may be presented. The second stage is hypothesis verification (HV). In this stage, all hypotheses are verified by Decision Tree (DT) training combined with a modified Genetic Algorithm (GA) to find the best features subset based on Haar-like feature extraction and an appropriate parameters set of Support Vector Machine for classification, which is robust for front and rear views of vehicle detection and recognition problems.
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Gajjar, P., K. van der Vaart, A. R. Thornton, C. G. Johnson, C. Ancey y J. M. N. T. Gray. "Asymmetric breaking size-segregation waves in dense granular free-surface flows". Journal of Fluid Mechanics 794 (4 de abril de 2016): 460–505. http://dx.doi.org/10.1017/jfm.2016.170.
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Debris and pyroclastic flows often have bouldery flow fronts, which act as a natural dam resisting further advance. Counter intuitively, these resistive fronts can lead to enhanced run-out, because they can be shouldered aside to form static levees that self-channelise the flow. At the heart of this behaviour is the inherent process of size segregation, with different sized particles readily separating into distinct vertical layers through a combination of kinetic sieving and squeeze expulsion. The result is an upward coarsening of the size distribution with the largest grains collecting at the top of the flow, where the flow velocity is greatest, allowing them to be preferentially transported to the front. Here, the large grains may be overrun, resegregated towards the surface and recirculated before being shouldered aside into lateral levees. A key element of this recirculation mechanism is the formation of a breaking size-segregation wave, which allows large particles that have been overrun to rise up into the faster moving parts of the flow as small particles are sheared over the top. Observations from experiments and discrete particle simulations in a moving-bed flume indicate that, whilst most large particles recirculate quickly at the front, a few recirculate very slowly through regions of many small particles at the rear. This behaviour is modelled in this paper using asymmetric segregation flux functions. Exact non-diffuse solutions are derived for the steady wave structure using the method of characteristics with a cubic segregation flux. Three different structures emerge, dependent on the degree of asymmetry and the non-convexity of the segregation flux function. In particular, a novel ‘lens-tail’ solution is found for segregation fluxes that have a large amount of non-convexity, with an additional expansion fan and compression wave forming a ‘tail’ upstream of the ‘lens’ region. Analysis of exact solutions for the particle motion shows that the large particle motion through the ‘lens-tail’ is fundamentally different to the classical ‘lens’ solutions. A few large particles starting near the bottom of the breaking wave pass through the ‘tail’, where they travel in a region of many small particles with a very small vertical velocity, and take significantly longer to recirculate.
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Zhang, Yifan, Dewang Li, Kui Wang y Bin Xue. "Contribution of Biological Effects to the Carbon Sources/Sinks and the Trophic Status of the Ecosystem in the Changjiang (Yangtze) River Estuary Plume in Summer as Indicated by Net Ecosystem Production Variations". Water 11, n.º 6 (17 de junio de 2019): 1264. http://dx.doi.org/10.3390/w11061264.
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We conducted 24-h real-time monitoring of temperature, salinity, dissolved oxygen, and nutrients in the near-shore (M4-1), front (M4-8), and offshore (M4-13) regions of the 31° N section of the Changjiang (Yangtze) River estuary plume in summer. Carbon dioxide partial pressure changes caused by biological processes (pCO2bio) and net ecosystem production (NEP) were calculated using a mass balance model and used to determine the relative contribution of biological processes (including the release of CO2 from organic matter degradation by microbes and CO2 uptake by phytoplankton) to the CO2 flux in the Changjiang River estuary plume. Results show that seawater in the near-shore region is a source of atmospheric CO2, and the front and offshore regions generally serve as atmospheric CO2 sinks. In the mixed layer of the three regions, pCO2bio has an overall positive feedback effect on the air–sea CO2 exchange flux. The contribution of biological processes to the air–sea CO2 exchange flux (Cont) in the three regions changes to varying extents. From west to east, the daily means (±standard deviation) of the Cont are 32% (±40%), 34% (±216%), and 9% (±13%), respectively. In the front region, the Cont reaches values as high as 360%. Under the mixed layer, the daily means of potential Conts in the near-shore, front, and offshore regions are 34% (±43%), 8% (±13%), and 19% (±24%), respectively. The daily 24-hour means of NEP show that the near-shore region is a heterotrophic system, the front and offshore regions are autotrophic systems in the mixed layer, and all three regions are heterotrophic under the mixed layer.
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Xin, Tang, Liu Zhili, Zhao Meng, Yang Haotian, Jiang Wei, Wang Yuchuan y Chen Diyi. "Analysis of Unsteady Flow Characteristics of Centrifugal Pump under Part Load Based on DDES Turbulence Model". Shock and Vibration 2021 (14 de junio de 2021): 1–11. http://dx.doi.org/10.1155/2021/9970800.
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To better reveal the mechanism of the rotor-stator interference between the impeller and the guide vane and the evolution process of the stall vortex under the part-load conditions, numerical simulation is carried out based on the DDES turbulence model, which can better capture vortex structure. And the pressure pulsation and the radial velocity distribution of the centrifugal pump are studied. The vortex structure and pressure fluctuation of pump internal flow field under part-load condition of Q = 0.4 Qdes are mainly analyzed. The analysis results show that the stall vortex is formed at the inlet of the impeller and evolves to the outlet of the impeller, the front cover to the rear cover according to the fluid flow direction, and then disappears. Besides, under the part-load condition, the vorticity of the impeller outlet is always obviously less than that of the impeller inlet as the flow rate increases. Due to the asymmetric action of the volute, the radial velocity distribution law of flow channel C1 is different from other flow channels at different blade heights. By analyzing the radial velocity, the phenomenon that the jet-wake flow impacts the guide vane with the rotation of the impeller is the main reason for the rotor-stator interference. And large radial velocity gradients appear at the front and rear cover plates, which will cause high energy loss and reduce pump efficiency. Besides, the conclusion can be drawn that the region with the strongest rotor-stator interference is the inlet region of the guide vane suction surface. It also occurs near the volute tongue but is lower due to the effect of the guide vane. This research may serve as a reference for the safe operation of centrifugal pumps under part-load conditions.
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Maiorova, Natalya S. "Population, and its social and religious composition in Ivanovo and Yaroslavl regions on the eve of the Axis aggression against the USSR (according to the censuses of the USSR in 1937 and 1939)". Vestnik of Kostroma State University 27, n.º 1 (31 de marzo de 2021): 74–78. http://dx.doi.org/10.34216/1998-0817-2021-27-1-74-78.
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The article is devoted to the analysis of the results of population censuses conducted in the USSR in 1937 and 1939, in relation to Ivanovo and Yaroslavl regions. The research is based on census materials that had been classified for a long time and published only in the 1990s. Of all the various aspects of the censuses, the author's attention was focused on only three – population, its social structure, and religious composition. Based on the results of the censuses, conclusions are drawn about the prevalence of women in the region, both in rural areas and in cities. It was women who, in the conditions of World War II, became the strong rear, on whose shoulders the front was supported by food, uniforms, and weapons. The urban population was greater in Ivanovo Region, which was explained by its characteristic high rates of industrialisation. The 1937 census recorded a fairly high level of religiosity, despite the largely anti-religious policy that had been carried out for almost 20 years. The war led to an increase in religiosity, probably because often only faith could become the core around which daily life was built, full of deprivation, anxiety and fear for loved ones.
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Goater, Alexander J. N. y Andrew J. Hogg. "Bounded dam-break flows with tailwaters". Journal of Fluid Mechanics 686 (27 de septiembre de 2011): 160–86. http://dx.doi.org/10.1017/jfm.2011.317.
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AbstractThe gravitationally driven collapse of a reservoir into an initially stationary layer of fluid, termed the tailwater, is studied using the nonlinear shallow water equations. The motion is tackled using the hodograph transformation of the governing equation which allows the solutions for velocity and depth of the shallow flowing layer to be constructed by analytical techniques. The front of the flow emerges as a bore across which the depth of the fluid jumps discontinuously to the tailwater depth. The speed of the front is initially constant, but progressively slows once the finite extent of the reservoir begins to influence the motion. There then emerges a variety of phenomena depending upon the depth of the tailwater relative to the initial depth of the reservoir. Provided that the tailwater is sufficiently deep, a region of quiescent fluid emerges adjacent to the rear wall of the reservoir, followed by a region within which the velocity is negative. Also it is shown that for non-vanishing tailwater depths, continuous solutions for the velocity and height of the flowing layer breakdown after a sufficient period and develop an interior bore, the location and time of inception of which are calculated directly from quasi-analytical solutions.
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Torres-Guijarro, Soledad, Antonio Pena, David Pérez-Cabo y Norberto Degara-Quintela. "A Study of Wideband Absorbers in a Non-Environment Control Room: Normal Absorption Coefficient Measurement and Analysis". Acta Acustica united with Acustica 98, n.º 3 (1 de mayo de 2012): 411–17. http://dx.doi.org/10.3813/aaa.918526.
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This contribution concludes the study initiated in [1] about the wideband absorbers of the rear wall in a nonenvironment control room at the “Universidade de Vigo”. The specific acoustic impedance will be calculated from microphone signals of a p-p intensity probe, and the H2 estimator will demonstrate that it provides the best estimate both at fixed measuring points and in scanning. The absorption coefficient calculated from the specific acoustic impedance is related to the sound field characterisation in the vicinity of the panels: in the very low frequency region it presents maxima and minima attributable to the behaviour of the channels between panels as open-closed tubes, and also shows the effect of the first transverse standing wave in fixed point measurements performed in the centre of the channel opening. This effect disappears in the scanning measurement providing an average absorption curve in a wide area in front of the absorbers. A simple model can be made from the results for the absorption of the wideband absorbers of the rear wall of the room.
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Aghazadeh, N. y H. Taghavifar. "Study on the Track Wheeled Vehicle Designing for Off-Road Operations on Snowy and Wet Terrains". Cercetari Agronomice in Moldova 48, n.º 4 (1 de diciembre de 2015): 5–12. http://dx.doi.org/10.1515/cerce-2015-0047.
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Abstract Off-road vehicle trafficking is of interesting subjects for agricultural, mining and civil engineering purposes. The traversing over snowy and wet terrain is of greater importance regarding the sinkage and terrain properties. The motion resistance, traction, sinkage, and vehicle stability are functions of wheel-terrain interactions and particularly the contact patch characteristics. As adoption of wheeled vehicles on snowy terrain is difficult, tracked wheel vehicles are of greater interest and applicability. In this paper, the designing and analysis of tracked wheel system mounted on a light weight all-terrain vehicle (ATV) is addressed. The designing considerations are based on semi-empirical models (Bekker and Mohr-Coulomb criterion) and experimentally obtained data on the snow mechanical properties for the test region. Based on the analysis, it is observed that the greatest value of total deformation for the front and rear chasses are obtained at 0.00028485 and 0.00026229 m, respectively. The von Mises yield criterion addresses that the yielding of materials starts when the second deviatoric stress invariant gets to a critical value close to failure. Furthermore, the greatest values of von Mises stress for the front and rear tracked wheel chassis are equal to 64.60 and 62.48 MPa, respectively. The similarity is that the critical point is situated at the coincidence point between the inclined and longitudinally oriented rods (joint point). It is concluded that the developed vehicle could serve as a functional vehicle to perform on different off-road operational condition particularly wet terrains.
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Vykydal, Petr, František Bauer, Pavel Sedlák y Adam Polcar. "The influence of the undercarriage and tire inflation rating on drawbar characteristics of tractors". Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 60, n.º 5 (2012): 255–64. http://dx.doi.org/10.11118/actaun201260050255.
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The aim of the measurement was to verify the drawbar characteristics of chosen tractors with different undercarriages. The tractors were of the same engine power as well as type of gearbox (PowerShift – gears full shifted while loaded). We were dealing with the wheeled tractor John Deere 8320 and crawler tractor John Deere 8320RT. The measurement was implemented in the land register of Vrbovec (Znojmo region) in an area where green peas were grown as the main product and winter wheat as the preceding crop. The measured and the counterproductive tractors were interconnected by the rope containing strain-gauge force sensors. The wheeled tractor was decelerated by the tractor crawler. The tractor crawler was decelerated by two wheeled tractors. The wheeled tractor’s stress-strain properties were also measured applying two pressure rating alternatives. Variant A presented inflation pressure of 160 kPa on the front axle and of 140 kPa on the rear axle. Variant B applied inflation pressure of 120 kPa on the front axle and of 100 kPa on the rear axle. Measured and calculated findings reveal that the tractor crawler achieved higher drawbar power and lower specific tractive consumption and traction slip than the wheeled tractor with both variants of inflation. Comparing the stress-strain characteristics of the wheeled tractor with a different tire inflation illustrates that using variant B, higher drawbar power and lower specific tractive consumption and traction slip were measured.