GEOGRAPHICAL GRADIENTS - AS A MEASUREMENT OF GEOGRAPHICAL SPACE

Предлагается более широкий круг градиентных измерений географического пространства. В природной сфере – различия в биоразнообразии и ландшафтном разнообразии. В природно-ресурсной сфере – различия в запасах и продуктивности природных ресурсов, имеющих пространственно непрерывное распределение (лесных, земельных), а также – различия в сочетаниях природных ресурсов. Возможны градиентные оценки различий расчетных величин, например, суммарного природно-ресурсного потенциала. В экологической сфере в виде градиентов можно оценивать различия в загрязнении или нарушенности земельного, растительного покрова. В социально-экономической сфере с помощью градиентов можно оценивать различия ряда расчетных величин: плотности населения, экономической плотности, полей тяготения поселений, поля потенциальных затрат и т.п. Предлагается градиентное измерение различий однородных характеристик поселения-центра и сочетания поселений, входящих в круг с условно единичным радиусом, проведенным из центра. A wider range of gradient dimensions of geographical space is proposed. In the natural sphere these are differences in biodiversity and landscape diversity. In the natural resource sphere these are differences in the reserves and productivity of natural resources, which have a spatially continuous distribution (forest, land), as well as differences in the combinations of natural resources. Gradient estimates of differences in the calculated values, such as the total natural resource potential, are possible. In the environmental sphere, differences in pollution or disturbance of land and vegetation cover can be estimated as gradients. In the socio-economic sphere, the gradients can be used to estimate differences in a number of calculated values: population density, economic density, gravity fields of settlements, potential cost fields, etc. A gradient measurement of differences in the homogeneous characteristics of a settlement-center and a combination of settlements, entering the circle with a conventionally single radius drawn from the center, is proposed.

Determination Coefficient of Stress Concentration Using a Conformed Display on a Circle of a Single Radius

Developed a mathematical model, which makes it possible to optimize, from the point of view of defect formation, the parameters of stress concentration in a deformable elastic body of the materials being processed, destruction is considered as a method for creating defects at a submicroscopic level in various media. Getting expressions of conformal reflection of single circle on an arbitrary area, using a conformal reflection and transformation of Laplace, it is possible to design behavior of a tensely deformed state of solid at the arbitrary loading.

A computational method for pass design of the four-roll rolling process for sizing of round sections

The four-roll rolling process (4RP) enables the further evolution of sizing processes in rolling mills for round sections. The well-known advantages of the three-roll process over the two-roll process can be further improved using the 4RP. The participation of four rolls in the deformation zone instead of three or two leads to a significant increase in deformation efficiency. The present work shows a pass design method for pass sequences in the four-roll rolling process. Here, three basic types of roll groove geometries are discussed: the flat groove, the non-opened single-radius groove, and a tangentially opened type of a single radius groove. Based on a predefined cross-sectional evolution, grooves are found numerically to satisfy two conditions, i.e., the cross section of the rolled section and the groove filling criterion. The equations of the equivalent pass method, together with a suitable model for lateral spread and the geometric equations of the groove are solved by nonlinear optimization to minimize the sectional and filling errors of a specific pass. Combined for several rolling passes, a complete pass design can be carried out for the reduction of a specified initial section to a final section. The presented results show, how a pass design method for the four-roll rolling process can be constructed. The newly developed model is implemented in a software solution for pass design and analysis of full section rolling mills. An exemplified pass design is discussed to show the possibilities and limitations of the new model.

Methods for determining the position of the curve in the plan and the influence of the geometry of the track on the indicators of interaction between the track and the rolling stock

The article substantiates the necessity of supplementing the existing estimate of the track position in the plan by the difference of adjacent bending arrows with an estimate of deviations from the fixed initial position, which ensures the constancy of the characteristics of a single-radius curve or the components of a multi-radius curve along their entire length. As a fixed initial position of the reference base (base position), it is proposed to accept the design position or the position of the track after the repair performed according to the project, and in the absence of the project, the calculated position obtained using verified programs. The question of determining the values of the deviation of the position of the curves at individual points from the base position and their ranking for different variants of recording the curves is considered. As possible options for surveying are considered Geodetic measurement methods using Cartesian and polar coordinate systems, methods of obtaining information from transformed data from sensors of track measuring cars, as well as the classical method of measuring the arrows of the bend of a curve.The article presents the results of calculating the indicators of the interaction between the track and the rolling stock (frame and horizontal transverse forces, lateral deflections of rails) when modeling the motion of a freight car along curves, the parameters of which were obtained on the basis of analysis of data from experimental sections. The calculation results are correlated with the analyzed data on the presence of deviations from the base position in the curves.

Comparison of functional outcomes between single-radius and multi-radius femoral components in primary total knee arthroplasty: a meta-analysis of randomized controlled trials

Purpose Our purpose in the current meta-analysis was to compare the functional outcomes in patients who have received single-radius (SR) or multi-radius (MR) femoral components in randomized controlled trials (RCTs) for primary total knee arthroplasty (TKA). The hypothesis was that there would be no statistically significant difference between two groups in terms of functional outcomes. Materials and methods We searched the international electronic databases PubMed, Embase, and the Cochrane Central Register of Controlled Trials up to February 2020 for RCTs that compared functional outcomes of SR and MR femoral component designs after primary TKA. We performed a meta-analysis of nine RCTs using the Knee Society Score for the knee (KSS-knee), KSS-function, Knee Injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score (OKS), degree of knee flexion, extension, and complications, including postoperative infection and revision surgery. Results The meta-analysis revealed no statistically significant differences in all the analyzed variables, including KSS-knee, KSS-function, KOOS, OKS, knee flexion, and knee extension. For postoperative complications, no statistically significant differences were detected for femoral component designs in postoperative infection or incidence of revision surgery between the two groups. Conclusions The current meta-analysis of RCTs did not show any statistically significant differences between SR and MR femoral component designs in terms of postoperative functional outcomes. Evaluated outcomes included functional outcome scores, degree of knee flexion, extension, and complications. However, because of the limited clinical evidence of this study owing to the heterogeneity between the included RCTs, a careful approach should be made in order not to arrive at definite conclusions.

Development of Multi-EAP Radius Configuration for eduroam Service

This paper describes the mechanism of authenticating multiple-realm eduroam users via a single multi-EAP radius configuration. The solution is based on the fact that some organizations, which are willing to join the eduroam community and use the service, especially in small communities, do not have a huge number of users, thus it will be costeffective to use a single RADIUS server for them instead of having a separate radius server per each realm. The solution is unmatched in terms of practical open implementation. It has been implemented and tested in ASNET-AM network.