The article explains the nonlinear balance model that considers disposal and recycling of wastes and investments. The suggested model is the equilibrium prices model in which the costs of harmful wastage disposal and recycling are considered. Besides, there are nonlinear interrelations between the branches of production, which allows us to predict the release of useful products, which is necessary for the economistsanalysts who are engaged in forecasting the manufactured products. For the model which is described by a system of differential equations, the conditions are created when the system of differential equations has only one solution. The paper defines the conditions under which this model is solvable and has a nonnegative solution, if at the same time the given values can be negative. For the model the methods of creating bilateral estimated solutions are adapted; the method of improving bilateral estimation is offered. Unlike the methods of searching the precise solution, the application of the method of bilateral estimation facilitates successful solution of tasks with big dimension of the processed models, without resorting to direct integration. The results of this article can be used in the solution of specific tasks of mathematics, economics, biology and other tasks with nonlinear interrelations.
In this work the research of heat-removing properties of areas of extended surfaces, for example, of finned and needle radiators for assessment of efficiency of distribution of a thermal field and heat extraction is described. Also the description of the carried-out computational modeling is provided in the Fluent processor of universal program system of the final and element analysis Ansys. The relevance of the selected subject is confirmed by the fact that one of the most important and difficult tasks arising when developing the electronic equipment is a withdrawal of heat generated by it. At a current steady trend in reduction of dimensions of electronic devices this problem does not disappear, and opposite, becomes more and more sharp, and that is stronger, than device high power less its physical volume, and not only the efficiency of heat extraction, but also dimensions and, of course, reliability of operation of electronic devices depends on constructions of heat-removing elements. In work the conclusion is drawn that for a solution of a complex problem of assessment of efficiency of the heat sink for the purpose of decrease in temperature of heatterminated element, it is necessary to use electrothermal analogy.
The paper describes a computational experiment and presents the results of numerical modeling of an axisymmetric body with an optimized shape with a minimum aerodynamic drag force as a heat sink in a convective gas flow. The resulting optimized body shape coincides with streamlines, which is the main advantage, since no separation of the flow from the surface is observed in the flow around. Thus, the entire surface area will be the effective surface area of the heat sink, unlike other known body shapes, due to which the temperature of the heat-loaded element placed in the center of the heat sink will decrease.
The article presents the results of experimental studies of the influence of polymer abrasive granules shape on the surface roughness formation and metal removal during vibrational finishing and hardening treatment (VFHT). As is known, surface roughness and the amount of metal removal are affected by a number of factors: binder material, material and granularity of the abrasive, technological lubricant-coolant medium (LCM) type, loading mass, initial roughness, etc. Processing was carried out for 120 min on a UVG-4x10 vibrating machine, with a working chamber volume of 10 dm3. Metal removal Q (grams) and surface roughness Ra (μm) were measured using an AD-200 analytical balance and an SJ-210 profilometer. The results presented show that polymer abrasive granules have high cutting ability, the intensity of which depends on the shape of the granules.
The paper presents the results of the study of possibility using a body with an optimized shape with a minimum aerodynamic drag force as a heat sink in a convective gas flow for cooling machine parts. The relevance of cooling or heat sink systems for mechanical engineering is not in doubt. Maintaining the optimum thermal state of machine parts within the specified limits is necessary to prevent heating, which can cause violations of normal operating conditions, and, as a result, increased wear, jamming and breakage of parts. To ensure the normal operation of the system, it is necessary to cool the parts contacting the hot gases, removing heat from them to the atmosphere directly, or using an intermediate body (water, low-freezing liquid). Heat sink is an aerodynamic process, a process of heat mass transfer of a substance, and aerodynamic characteristics and, in particular, the nature of streamlining of bodies of the simplest forms are of great scientific and practical interest. Bodies of complex shape can always be represented as a combination of simpler ones, for which it is easy to explore and calculate the flow paths, on the basis of which analytical methods for calculating aerodynamic characteristics are compiled. A computational experiment was conducted in the software product Ansys Fluent. The conditions of the experiment (comparison of heat removal bodies) during numerical modeling are the preservation of constants: the volume and shape of the working zone; distances from the sources, drains and centers of bodies; aerodynamic flow rates; masses of compared bodies; thermal power of the source and other parameters in addition to the shape of the surface. The resulting optimized shape of the body coincides with the current lines, which is the main advantage, since no separation from the surface is observed when streamlining the flow. Thus, the entire surface area will be the effective surface area of the heatsink as opposed to other known shapes of bodies, whereby the temperature of the heat loaded element placed in the center of the heatsink will decrease.
This article is devoted to the analysis of problems and prospects of development of the social trust system (social rating) in the People's Republic of China. At the same time, the authors conclude that the development and implementation by the state of behavioral control systems for both individuals and legal entities is a necessity to ensure optimal management of all areas of society. However, their implementation should be carried out under the constant supervision of civil society institutions (in particular, through the functioning of the institute of public control). The author uses a number of methods of scientific research, in particular: analysis; synthesis; interpolation; extrapolation; comparative legal; historical; sociological and a number of others. The paper examines the genesis of the social trust system (social rating) in the People's Republic of China, formalizes and justifies the author's classification of the stages of its formation and development, analyzes the impact of this system on the processes of implementation and protection of the system of constitutional rights and freedoms of citizens of the People's Republic of China, identifies and formalizes not only the main problems hindering the development of this system, but also the main directions of this development. The paper analyzes the impact of the social trust system (social rating) in China on the formation and development of behavioral surveillance systems initiated by public authorities in various countries, including the Russian Federation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.