Uneven Reduction Research Articles

Components of the development of methods for calibrating rollers for rolling channels based on changed non-uniformsty of deformation

Introduction. In metallurgy, the final stage of production is metal processing in rolling shops. The main component of the development of technologies for rolling graded profiles is the calibration of rolls. 90% of the steel that is smelted is processed by rolling. Rolling mill calibration methods are constantly being improved. Calibration methods are used in which there is a significant uneven deformation of the profile elements, which leads to rapid wear of the rolls and an increase in costs. Formulation of the problem. It is necessary to develop a method of calibrating rolls in the production of channels based on the reduction of deformation unevenness. Goal. The purpose of the article is to analyze the methods of calibrating rolls for the production of channels with an indication of their advantages and disadvantages and to justify the application of the components of the developed method of calibrating rolls based on the reduction of unevenness of deformation. The results. The analysis of various methods of calibrating channel rolls showed that the smallest unevenness of deformation is present in the method of rolling by the bending method. The greatest uniformity of deformation along the width of the profile is achieved, the wear of the rolls is reduced in connection with ensuring a minimum difference in the diameters of the rolls in the gauge, and energy costs are reduced. To reduce the uneven deformation of the metal, it is suggested to use a rectangular blank or strip. Scientific novelty. For the first time, the methods of calibrating rolls for channel rolling were analyzed in detail. To reduce uneven deformation of shelves and flanges in the center of deformation in the gauge, it is proposed to use the bending calibration method. It is proposed to use strips as a blank for the first time. Practical meaning. The application of channel rolling technology based on the developed method of calibrating rolls with reduced unevenness of deformation in the first passes allows to reduce the cost of products and give an economic effect

Study on association factors of intestinal infectious diseases based-Bayesian spatio-temporal model

BackgroundIntestinal infectious diseases (IIDs) are a significant public health issue in China, and the incidence and distribution of IIDs vary greatly by region and are affected by various factors. This study aims to describe the spatio-temporal trends of IIDs in the Chinese mainland and investigate the association between socioeconomic and meteorological factors with IIDs.MethodsIn this study, IIDs in mainland China from 2006 to 2017 was analyzed using data obtained from the China Center for Disease Control and Prevention. Spatio-temporal mapping techniques was employed to visualize the spatial and temporal distribution of IIDs. Additionally, mean center and standard deviational ellipse analyses were utilized to examine the spatial trends of IIDs. To investigate the potential associations between IIDs and meteorological and socioeconomic variables, spatiotemporal zero-inflated Poisson and negative binomial models was employed within a Bayesian framework.ResultsDuring the study period, the occurrence of most IIDs has dramatically reduced, with uneven reductions in different diseases. Significant regional differences were found among IIDs and influential factors. Overall, the access rate to harmless sanitary toilets (ARHST) was positively associated with the risk of cholera (RR: 1.73, 95%CI: 1.08-2.83), bacillary dysentery (RR: 1.32, 95%CI: 1.06-1.63), and other intestinal infectious diseases (RR: 1.88, 95%CI: 1.52-2.36), and negatively associated with typhoid fever (RR: 0.66, 95%CI: 0.51-0.92), paratyphoid fever (RR: 0.71, 95%CI: 0.55-0.92). Urbanization is only associated with hepatitis E (RR: 2.48, 95%CI: 1.12-5.72). And GDP was negatively correlated with paratyphoid fever (RR: 0.82, 95%CI: 0.70-0.97), and bacillary dysentery (RR: 0.77, 95%CI: 0.68-0.88), and hepatitis A (RR: 0.84, 95%CI: 0.73-0.97). Humidity showed positive correlation with some IIDs except for amoebic dysentery (RR: 1.64, 95%CI: 1.23-2.17), while wind speed showed a negative correlation with most IIDs. High precipitation was associated with an increased risk of typhoid fever (RR: 1.52, 95%CI: 1.09-2.13), and high temperature was associated with an increased risk of typhoid fever (RR: 2.82, 95%CI: 2.06-3.89), paratyphoid fever (RR: 2.79, 95%CI: 2.02-3.90), and HMFD (RR: 1.34, 95%CI: 1.01-1.77).ConclusionsThis research systematically and quantitatively studied the effect of socioeconomic and meteorological factors on IIDs, which provided causal clues for future studies and guided government planning.

Fluid structural interaction simulation of the MP-1 plate performance irradiated in the advanced test reactor

Due to the high neutron fluxes they generate and increased heat transfer performance, plate type fuels are used in the U.S. high-performance research reactors. During irradiation, a significant amount of fission energy (i.e., ∼200 MeV per atom) is released by the U-235 chain reaction that is carried away by the coolant. Through thermal hydraulic analysis, the coolant’s heat transfer capability is investigated to ensure that the desired fuel temperature can be maintained. At high temperatures, the plate undergoes elastic/plastic deformation, creep, and swelling as a result of both the temperature gradients and the fission gas production within the fuel. These effects are studied via fuel performance analysis. When the plate deformation is small enough that the coolant flow remains relatively unchanged, conducting these two types of analyses independently will suffice. But at high fuel burnups, the swollen plates may encroach into the coolant channels that separate the fuel plates from each other and cause these channels to narrow. Large reductions in channel gap size imperil cooling performance, causing fuel temperatures to rise. If the plate deformation is asymmetric, the fuel centerline will shift toward one side of the channel, causing an uneven reduction in coolability. In addition, a boehmite (oxide) layer will, over time, grow on the plate surface, further obstructing the heat transfer process. To precisely predict fuel temperatures/deformation, a complete coupled analysis that considers coolant flow, heat transfer, oxide growth, elastic/plastic deformation, creep, and swelling is needed; however, this type of analysis method is not available in the literature. To fill the gap, this research developed a fluid structure interaction (FSI) approach to the fuel plate analysis, then successfully applied it to the Mini-Plate (MP)-1 experiment, which was irradiated in the Advanced Test Reactor (ATR) for both one and two cycles. The complete analysis coupled STAR-CCM+, a computational fluid dynamic (CFD) software for calculating flow, with Abaqus, a finite element analysis code for calculating plate deformation. Improvements in the results were found when comparing the fully coupled analysis to the independently conducted analyses but they were not significant due to the miniature size of the plates and the relatively short irradiation time. In the future, the fully coupled approach presented herein will be applied to full-size fuel plates with longer irradiation cycles once additional experiments become available.

How the pandemic affected interregional inequality in Russia

ABSTRACT Analysis of trends in interregional inequality in Russia in 2015–21 and of the actual outcome during the 2020 pandemic and the subsequent recovery in 2021 reveals short-term regional convergence in seven indicators, albeit of different depth and duration. Sub-federal budget revenue experienced the most significant and persistent reduction in interregional disparities, the main sources of which were a reduction of unevenness in a number of taxes, a significant increase in federal transfers and a change in their nature. After a strong short-term convergence, industry, trade, transport and investment all tended to return to long-term divergence paths. Personal income and wage inequality responded weakly to the shock in the short term and entered the new long-term path. Multidirectional spatial trends resulted from the interaction of sectorial and fiscal policy effects during the pandemic.

Covid-19 pandemic impacts on follow-up of child growth and development.

ABSTRACTOBJECTIVE To analyze the impact of the covid-19 pandemic on the use of primary health care services to follow-up the child growth and development in Brazil.METHOD A total of 7.9 million consultations of children (0–2 years old) across Brazil between March 2017 and May 2020 were studied. Differences between medians were analyzed using non-parametric tests, the Global Moran Index (IGM) and the Local Indicators of Spatial Association.RESULTS During the initial period of the pandemic, the median number of consultations was significantly lower than the same period in previous years, reducing more than 50%. The drop in 2020, compared to 2019, ranged from 49% to 62.2% across all regions of the country, except the South. The percentage reduction registered in 2019–2020 showed significant spatial autocorrelation (IGM = 0.20; p = 0.04), with the presence of low-low (states with reduction between 29% and 51%) and high-high (states with reduction between 55% and 69%) spatial clusters.CONCLUSION The covid-19 pandemic impacted the follow-up of child growth and development in primary health care services in Brazil, with a geographically uneven reduction.

Indoor and Ambient Air Pollution in Chennai, India during COVID-19 Lockdown: An Affordable Sensors Study

The Tamil Nadu Air Pollution and Health Effects study (TAPHE-2) aims to evaluate the relationship between air pollution and birth outcome in a rural-urban cohort of 300 pregnant women. Due to COVID-19 related lockdowns, some TAPHE-2 activities were delayed; however, continuous indoor and outdoor air quality data were collected in and around Chennai, India. We report here the impact of graded COVID-19 lockdown on indoor particulate matter (PM2.5 and PM10) levels based on calibrated data from affordable real-time PM sensors called atmos™ and ambient PM levels from publicly available regulatory monitors. The study period was between 11 March and 30 June 2020 (i.e., 100 days of continuous monitoring), which coincided with four phases of a nationwide graded lockdown. Field calibration coefficients for the atmos PM were derived by collocating them with reference-grade PM monitors. The normalized root mean square error (NRMSE) of the atmos hourly PM2.5 (PM10) improved from 41% to 15% (33% to 18%) after applying the field calibration coefficients. Lockdowns resulted in significant reductions in indoor and ambient PM levels, with the highest reduction observed during lockdown phase 2 (L2) and phase 3 (L3). Reductions as high as 70%, 91%, and 62% were observed in ambient PM2.5, indoor PM2.5, and indoor PM10 relative to pre-lockdown levels (PL), respectively. The indoor PM2.5/PM10 ratio decreased during the lockdown, suggesting a decline in the fine mode dominance in PM10. The indoor-to-outdoor (I/O) ratios in PM2.5 marginally increased during L1, L2, and L3 phases compared to that of PL levels, suggesting an uneven reduction in indoor and ambient PM2.5 levels during the lockdown.

Exploring polymerisation of 1,2-dicarbonyl compounds to decipher the formation of nitrogen-free substructures in melanoidins

• MGO or 3-DG can be reacted under different pH conditions to form polymers. • MW of the structural units of the polymers was mainly 54 ± 2 or 72 ± 2 Da. • Polymers can be cross-linked with gluten and dextran to form macromolecules. • Polymers are the nitrogen-free substructure in melanoidins. • Polymers can be used as candidate biomarkers. To decipher the formation mechanism of nitrogen-free substructures in melanoidins, methylglyoxal or 3-deoxyglucosone was used as a substrate to react by aldol reaction under different pH conditionst. The obtained products were characterised by chromatography, mass spectrometry, and spectroscopic methods. Overall, the molecular weights of the polymers structural units varied mainly within 54–56 and 72–74 Da, respectively, due to the different dehydration extent of β-hydroxy aldehyde or ketones, and uneven reduction by NaBH 4 . Moreover, the nitrogen-free substructures formed by this reaction can cross-link with gluten and dextran to form melanoidins. Therefore, the nitrogen-free substructures by this reaction to formed with units of 54–56 and 72–74 Da, which are similar as the typical polymers in food melanoidins. It is inferred that the typical polymers in food may also be formed by this pathway and which can be used as a detectable biomarker in melanoidins.

Impacts of spatiotemporally uneven urbanization on sea breeze fronts in a mega-river delta

Assessing the impacts of urbanization on the inland penetration of sea breeze fronts (SBFs) is an urgent requirement if we are to mainstream nature-based solutions in urban planning of coastal cities. SBFs are vital for the natural ventilation in urban areas. However, the interactions between SBFs and urbanization remain unclear in a mega-river delta, which often undergoes spatiotemporally uneven urban development. This study uses sensitivity experiments to examine the 1990, 2005, and 2016 SBF scenarios from Shanghai, China. We utilized a weather research and forecasting model to evaluate the SBF response to urbanization that incorporated both temporal variability; i.e., different rates of urban expansion and renewal, and spatial variability; i.e., uneven urban growth at various distances from the coastline. Furthermore, the contribution of thermal and aerodynamic factors to the SBF inland penetration was quantitatively separated using multiple regression models, into which dummy variables that measure urbanization-related roughness factors were introduced. The results show that maximum SBF inland penetration distances followed a temporally uneven reduction pattern, with rapid rates of reduction between 1990 and 2005 (4.1–6.3 km/10 yr), and slow rates of reduction between 2005 and 2016 (0.3–2.1 km/10 yr). These distances were also spatially uneven, with SBFs in southeast Shanghai being >10 km deeper than those in the northeast. In addition, the SBF inland penetration models indicate that surface roughness with negative effects, as well as urban heat island and normalized wind direction with positive effects are the three most important controls on penetration distance. These findings suggest that urban planners should therefore account for controlling coastal development, urban renewal measures, and urban ventilation, which could be important contributors to maximizing the role of SBFs in improving the urban environment in a natural way.

SKUBI MEDICINOS PAGALBA: TARPHOSPITALINIAI PERVEŽIMAI

In this article an emergency medical assistance and the inter hospital transfer problems are analysed in context of the restructurization of health care institutions and services, also of regionalization and centralization policy in Lithuania. Though the increased accessibility of health care services and improvement of the quality, also reduction of social exclusion and unevenness of provision of health care services are declared as the main objectives (purpose) of restructurization, however increased number of inter hospital transfers and crowding of the Emergency Departments indicate the possible negative tendencies. One of the substantial (fundamental) requirement of the inter hospital transfers is the continuous emergency care during transportation. The article provides a unified concept of second transportation between hospitals. The survey results contain the points of specialists and executives of emergency medical assistance on the current management situation of inter hospital patient flow and the ways how the management of patient flow can be improved. The study was made using questionnaire survey, the questions were divided into separate groups by the objectives of this study. Reasoned conclusions and the scheme of the emergency medical care patients flow are developed with reference to the results of this study.

Reduction of Unevenness of Discharge from a Pipe with a Longitudinal Slot

Reduction of Unevenness of Discharge from a Pipe with a Longitudinal Slot

Methods of Reduction of Unevenness of the Transfer Characteristic of the Shaper of Analog Counting of Digital Synthesizers of Signals with Uniform Sampling

Digital methods of decrease of nonuniformity of the transmitting characteristic of the shaper of analog counting of digital synthesizers of signals with the uniform sampling are offered. The second method can be used also for decrease of noise of digital-to-analog transformation. Decrease in nonuniformity of the transmitting characteristic of the shaper of analog counting leads to increase in probability of the exact detection and allowing ability of radar stations

Evidence for heterogeneity in China\u2019s progress against pulmonary tuberculosis: uneven reductions in a major center of ongoing transmission, 2005\u20132017

BackgroundChina contributed 8.9% of all incident cases of tuberculosis globally in 2017, and understanding the spatiotemporal distribution of pulmonary tuberculosis (PTB) in major transmission foci in the country is critical to ongoing efforts to improve population health.MethodsWe estimated annual PTB notification rates and their spatiotemporal distributions in Sichuan province, a major center of ongoing transmission, from 2005 to 2017. Time series decomposition was used to obtain trend components from the monthly incidence rate time series. Spatiotemporal cluster analyses were conducted to detect spatiotemporal clusters of PTB at the county level.ResultsFrom 2005 to 2017, 976,873 cases of active PTB and 388,739 cases of smear-positive PTB were reported in Sichuan Province, China. During this period, the overall reported incidence rate of active PTB decreased steadily at a rate of decrease (3.77 cases per 100,000 per year, 95% confidence interval (CI): 3.28–4.31) that was slightly faster than the national average rate of decrease (3.14 cases per 100,000 per year, 95% CI: 2.61–3.67). Although reported PTB incidence decreased significantly in most regions of the province, incidence was observed to be increasing in some counties with high HIV incidence and ethnic minority populations. Active and smear-positive PTB case reports exhibited seasonality, peaking in March and April, with apparent links to social dynamics and climatological factors.ConclusionsWhile PTB incidence rates decreased strikingly in the study area over the past decade, improvements have not been equally distributed. Additional surveillance and control efforts should be guided by the seasonal-trend and spatiotemporal cluster analyses presented here, focusing on areas with increasing incidence rates, and updated to reflect the latest information from real-time reporting.

TECHNOLOGICAL PARAMETERS OF THE COOLING MODE OF POLYMER INSULATION OF POWER CABLES

Introduction . The cooling mode of polymer insulation after application to the extruder is one of the main factors determining cable performance. Theoretically, it is ideal to cool the insulation when the temperature of the cooling medium is equal to the melting point of the insulation material: in this case, the probability of formation of voids in the insulation is less. The cooling process is usually not subject to stringent requirements, since most insulating materials allow for quite sharp cooling. The exception is polyethylene, which requires gradual cooling. When the insulation is cooled in a cooling bath, the temperature decrease starts from the surface. In this regard, the cooling of the insulation of polyethylene is carried out in steps to a temperature at which the cooled extruded insulation will not be deformed or damaged on the receiving drum. Polyethylene is characterized by a large value of thermal expansion coefficient, the maximum value of which is in the temperature range (90-125) °C. As a result, there is an uneven reduction in the volume of the upper and inner insulation layers, especially for cables with a considerable insulation thickness. The rapid cooling of polyethylene leads to the formation of cracks, air inclusions both between the insulation and the conductive core, and in the layers located near the core. Purpose. The substantiation of the technological parameters of the cooling mode of power cables based on the calculation of the thermal equivalent circuit of a conductive core insulated with polyethylene in transient thermal mode. Methodology. The calculation of the temperature distribution in the thickness of extruded polyethylene insulation at different points in time, depending on the temperature of the cooling water, is made by the method of electrothermal analogies. There is a transition from the thermal equivalent circuit of power cables to the equivalent circuit of the discrete resistive equivalent circuit method, which is calculated using the nodal potential method. As a result of solving a three-diagonal system of linear algebraic equations by sweeping and finding at each discretization step (time step) thermal power fluxes in the branches of the thermal equivalent circuit, the temperature in the thermal capacitances determines the temperature in each insulation layer. Practical value. The duration of the transition process, corresponding to the achievement of the same temperature throughout the thickness of the insulation, can be considered as a criterion in determining the length of the cooling bath sections depending on the extrusion (reception) rate.

Influence of Fishing Activity on Total Species Richness and Abundance Unevenness in Reef Fish Communities: A Case Study in a Brazilian Tropical Coral Complex

The internal organization of reef-fish communities, particularly the species richness and the hierarchical structuring of species abundances, depends on many environmental factors, including fishing intensity and proportion of macroalgal cover which are expected to have determinant influences. However, reported studies on this topic are generally based on incomplete samplings (almost unavoidable in practice when dealing with highly uneven and species-rich communities), so that the derived results can be appreciably skewed. To overcome this difficulty, the incomplete samplings involved in this study were completed numerically through a reliable extrapolation procedure. This precaution provided a safe confirmation that reduced fishing activity and increased macroalgae cover both contribute to enhance the total species richness and to reduce the abundance unevenness in these reef fish communities. Yet, it is shown that this reduction of abundance unevenness is almost entirely attributable to the increase in species richness.

The role of organic matter in formation of the properties of a shale deposit

Baltic oil shales — kukersites were studied as an example of rocks with rock-forming organic matter (OM). The volumetric significance of their OM is shown (due to the low density) in the volume and thickness of the shale layers. A higher OM content is responsible for a lower strength of the shales relative to the carbonate rocks of the deposit. The variable OM contents and other heterogeneities of the shale layers (structure, nodules, etc.) are factors of the mosaic distribution of areas with different density–strength properties and, as a result, of uneven reduction of layers and their deformation in the case of OM loss (full or partial). It is concluded that the intercalation of kukersite and limestone layers leads to density and strength anisotropy of the shale deposit. Episodic loss of OM and carbonates by the shales is considered for the local areas of the deposit: here, kukersites contain only a terrigenous component with clasts of limestones, shales, and epigenetic sulfides. The loss of OM is explained by sulfate-reduction processes in the underground hydrosphere.

The Role of Organic Matter in Formation of the Properties of a Shale Deposit

Baltic oil shales–kukersites were studied as an example of rocks with rock-forming organic matter (OM). The volumetric significance of their OM is shown (due to the low density) in the volume and thickness of the shale layers. A higher OM content is responsible for a lower strength of the shales relative to the carbonate rocks of the deposit. The variable OM contents and other heterogeneities of the shale layers (structure, nodules, etc.) are factors of the mosaic distribution of areas with different density–strength properties and, as a result, of uneven reduction of layers and their deformation in the case of OM loss (full or partial). It is concluded that the intercalation of kukersite and limestone layers leads to density and strength anisotropy of the shale deposit. Episodic loss of OM and carbonates by the shales is considered for the local areas of the deposit: here, kukersites contain only a terrigenous component with clasts of limestones, shales, and epigenetic sulfides. The loss of OM is explained by sulfate-reduction processes in the underground hydrosphere.

Problem Child Greece

In summer 2018, Greece left the EU rescue umbrella. Enormous efforts were made by the Greek state and its population to cut back its over-consumption and recurring new debt. The austerity measures were associated with numerous reforms aimed at advancing the Greek economy. Doubts that sustainable success was achieved are more than justified. The positive development of net exports, for example, was mainly at the expense of investment. This led to an enormous and uneven reduction of capital stock. With one exception, the structure of investments in capital stock is not optimal and should be readjusted according to the current available data.

Robust Design Optimization of Hydrodynamic Characteristics of Airfoil 791

In this paper, the influence of the continuous random variation of the flow velocity on hydrodynamic characteristics of airfoil 791 was discussed, and a robust design optimization method was proposed to reduce the influence of uncertain factors on the stability of hydrodynamic performance. Firstly, Bezier curve was used to parameterize the suction side of the airfoil, and its thickness was controlled by four points, which was then taken as the optimization variables. Secondly, the criterion of robustness was given, and then a robust mathematical model was established. Finally, two objective functions of robust optimization were gained on the basis of uncertainty analysis with surrogate model. Combined with multi-objective genetic algorithm, a robust optimal solution with better hydrodynamic characteristics was obtained. The results showed that compared with original case, the thickness near trailing edge altered more smoothly, the resistance and surface wave intensity were obviously decreased, and the maximum reduction of drag-lift ratio and wake unevenness were 6.89% and 25.04% respectively, which contributed to the improvement of wake quality. The change of surface pressure and resistance coefficients were also more stable under the variable inlet flow velocity conditions, and then the robustness was strengthened accordingly. In conclusion, the robust design optimization can obviously improve the hydrodynamic characteristics of the airfoil while reducing the sensitivity to uncertain factors, meanwhile, it can provide better stability during the operating process.

Winding method selection for technical implementation of fiber optic communication line for high-speed object

The paper deals with fiber-optical cable winding methods for realization of fiber-optic communication line with high-speed object. We consider possible options of coils for optical cable winding providing mobility of one of the cable ends on an object. It is shown that the choice of a winding process is caused by the need of ensuring the minimum deformation of fiber-optical micro cable in case of separation from a winding body. It is revealed that the minimum tension value and its unevenness are observed when reeling from coils with a rocket form. Design ratios for determination of winding parameters are given. It is shown that reduction of tension unevenness reduces the jumps of internal tension and probability of break and emergence of optical signal local attenuation. Decrease in internal stresses occurs due to the absence of overlapping of the coils of the underlying layers with the overlying ones. To confirm the operability and the possibility of constructive implementation of the selected winding scheme, experiments were carried out to perform rocket and other types of winding with the use of a specially designed machine model. It is shown that the application of line rocket winding enables to achieve stability when reeling a cable during the movement and excludes breaks. Attenuation of optical signal decreases due to the increase in the bend minimum radius. This phenomenon is explained by reduction of the internal stresses causing optical signal attenuation in the place of cable separation from the coil.

Large but uneven reduction in fish size across species in relation to changing sea temperatures.

Ectotherms often attain smaller body sizes when they develop at higher temperatures. This phenomenon, known as the temperature-size rule, has important consequences for global fisheries, whereby ocean warming is predicted to result in smaller fish and reduced biomass. However, the generality of this phenomenon and the mechanisms that drive it in natural populations remain unresolved. In this study, we document the maximal size of 74 fish species along a steep temperature gradient in the Mediterranean Sea and find strong support for the temperature-size rule. Importantly, we additionally find that size reduction in active fish species is dramatically larger than for more sedentary species. As the temperature dependence of oxygen consumption depends on activity levels, these findings are consistent with the hypothesis that oxygen is a limiting factor shaping the temperature-size rule in fishes. These results suggest that ocean warming will result in a sharp, but uneven, reduction in fish size that will cause major shifts in size-dependent interactions. Moreover, warming will have major implications for fisheries as the main species targeted for harvesting will show the most substantial declines in biomass.