We analyze the interplay between labeled trees and the ultrametric spaces they present. We provide characterizations of labeled trees that generate separable ultrametric spaces and those that generate locally finite ultrametric spaces. In particular, we establish an analog of König's Infinity Lemma for locally finite ultrametric spaces generated by labeled trees.
This study focuses on the development and evaluation of a new press design for separating rolled metal products. The goal of this design is to increase energy efficiency, reduce cutting force, and improve workpiece geometric accuracy compared to traditional crank presses. A wedge-hinged mechanism with a concave wedge is proposed, enabling a hybrid cutting process combining shear and torsion. The arcuate path of the cutting knife creates a stress concentrator that initiates material fracture and minimizes plastic deformation. The proposed method reduced energy consumption by 26
The article presents the place of advertising in the marketing strategy of a trading enterprise. The generalized forms of wholesale trade in Ukraine and elements of wholesale information structure are presented. It is established that in modern conditions of doing business, cardinal changes are taking place in approaches to advertising and sales activities of trading enterprises: focus on consumer needs, fierce competition, significant impact of scientific and technological progress on all spheres of life have determined that the basis of sales activities of trading enterprises is marketing activities and marketing management. The problems faced by trading enterprises are identified: problems of forming a product policy, maintaining a balance of interests of all market participants, insufficient information provision about markets and new technologies, adaptation to dynamic changes in the external environment, effective management of material, human resources and sales of goods. The phases of assessment of advertising and sales activities of domestic trading enterprises are analyzed.
Cold volume deforming is one of the progressive methods of obtaining high-quality products. One of the tasks of cold volume deforming processes is to increase the limiting dimensions of parts and ensure their high and stable mechanical properties. This problem can be solved by introducing new progressive and innovative methods of volume plastic processing. Such methods include combined step-by-step processes of cold volume extrusion. These processes are difficult to implement, but allow to get products of complex configuration with increased limiting dimensions. Since combined processes are characterized by deformation in several stages, there is a problem of assessing the deformability of the workpiece due to multiple changes in the nature of the load. Therefore, in the article, using the example of the extrusion process of a rod with a flange, a sequence of calculations of the used plasticity resource, taking into account the features of the non-monotonic load, was proposed. The main elements of this sequence include the evaluation of the kinematic characteristics of plastic flow using spatial and material reference frames, the assessment of the stress state based on the model of an anisotropically hardening body, and the determination of the value of the used plasticity resource applying a tensor approach of the damage accumulation process, which includes a component of the guiding indicator in the integrand. As a result, the deformability of the workpiece in the combined process of radial extrusion with subsequent upsetting of the flange obtained was estimated. The value of the used plasticity resource at characteristic points of the workpiece volume was determined. For workpieces made of steel 1010 and aluminum alloy AA3003, it has been shown that radial extrusion followed by flange upsetting makes it possible to obtain a flange with a diameter almost 3 times greater than the initial diameter of the workpiece.
The article presents a comprehensive study of cold extrusion processes for hollow semi-finished products made of AISI 1015 steel, intended for further drawing with thinning. The finite element method was applied in the DEFORM environment using an elastic-plastic metal model. The results of traditional reverse extrusion and reverse extrusion with expansion in a movable die were considered and compared. The dependencies of the extrusion forces, the extraction of punches from deformed workpieces, and the ejection of semi-finished products from dies on the movement of tools were determined. The exact distributions of specific forces on punches, ejectors, and dies were established. The distributions of temperature, stress components, and deformations in the deformed metal of semi-finished products at the end of the extrusion processes were determined. The metal structure was evaluated by cold plastic deformation based on the distribution of deformation intensity. The results presented for the extrusion process with expansion in a movable die are new. When using a movable die, lower deformation forces and specific forces were obtained, as well as a more uniform and deeper processing of the metal structure, which has a positive effect on the mechanical properties of the semi-finished product. Based on the simulation results, an extrusion die was designed and manufactured, and experimental tests were conducted on a hydraulic press. A good match was found between the calculated and experimental data for the extrusion force. The study allows for the optimization of the manufacturing technology for precision semi-finished products and contributes to an increase in the service life of the forming tool.
