Effective reengineering of the main activity of the enterprise requires a systematic approach, covering all stages from project preparation to its implementation. The article shows the algorithm for ...reengineering the production processes of the enterprise and its implementation on the example of one of the leading manufacturing enterprises of the Krasnoyarsk Territory, Russia. The algorithm includes the construction of structural-functional models using the AllFusion Process Modeler (BPWin) software environment common in Russia and simulation based on the Arena product. A user can develop a technological process or process flow diagrams, as is usually done when describing "as-is" business processes or when designing a "to-be" business process, and then export them to Arena applying these tools together. Reengineering of the main processes according to the proposed stages of the methodology helps to evaluate their effectiveness before making direct changes.
The article describes a simulation model that describes the fluctuations of the system. It is possible to track changes of fluctuations in stocks levels, as well as in production. Fluctuations occur ...when the behavior of the model deviates above or below the equilibrium point. If the oscillations damp, they will become less and less and eventually disappear in the absence of an external force that stimulates them. This model was built with the help of the program Powersim Studio 7 Express. The input interface of the model is shown. It includes such data as "Equipment correction time", "Changing timeout", "Inventory", "Equipment" and "Expected demand". This model contains three constants, two auxiliary variables, two drives and three streams. An experiment was conducted on the input data. As a result of the experiment an output interface was created and it includes such graphs as "Behavior "Expected Demand", "Order Level" and "Production" during the simulation" and "Comparison of "Equipment" and "Required Equipment" during the simulation". According to these graphs, it is possible to track the actual and necessary equipment used in production, as well as understand how much needs to be produced to cover the discrepancies between stocks and desired stocks, as well as expected consumer demand.
Investments in real estate are considered by investors as the best way to preserve and increase capital in the long term. Investing in real estate allows the investor to dispose independently of the ...acquired property at his discretion, including giving and inheriting, and using it for investment purposes - to lease or resell for profit. It is proposed to analyze the algorithm of actions to facilitate the decision-making on the investment purchase of residential real estate and to work out some "unchanged" points of the algorithm that can help in making this decision. Based on this, the stages that are included in this algorithm are analyzed, as well as three types of strategies for investing in residential real estate. A program is considered that allows calculating the profitability of investing in an object for an investor for each type of strategy, using certain factors associated with the property.
The influence of the geometry and materials of a plasma reactor on the oxidation of propylene in the presence of water has been studied. One- and two-barrier discharge cells with coaxial and planar ...arrangement of electrodes have been considered, with the dielectric barriers being made of Pyrex glass or fiberglass laminate. It has been shown that the geometry and material of the reactor electrodes do not significantly affect the composition and amount of the products. The main products of propylene oxidation are compounds with the general formula C
3
H
x
O, C
1
–C
4
hydrocarbon gases, methanol, and acetaldehyde. Hydrogen peroxide and nitrate ions were identified in the aqueous solution; the pH of the solution changed from 7 to 3. For the reactor with one dielectric barrier, metals from the electrode surface have been found to be slightly carried over into the aqueous solution.
The article discusses the construction of a simulation-dynamic model of inventory management for production. The model is built taking into account the following factors: production, shipping, ...desired demand, desired productivity, labor and others using Powersim Studio. A model management interface was created, which includes an input interface through which input of initial data is carried out, as well as an output interface that allows seeing the difference between demand and production, the actual and desired workforce, as well as the current and desired inventory. On the basis of the experiments, conclusions were drawn regarding the available data, and a comparison of the results of the experiments was carried out, as well as illustrating how the model visualizes changes in the process of inventory management.
The article is devoted to a review of approaches used to simulate thermal processes occurring during electron beam welding of thin-walled products. The analysis of more than fifty sources is carried ...out on the basis of which ideas about the current state of the problem considered in the article are formed. To implement the simulation, it is possible to use modern software systems such as: ANSYS, Comsol Multiphysics, Abaqus and NX Nastran, each of which has its own set of advantages and disadvantages. By using the method of expert evaluation on the basis of the formulated criteria, the most effective software was selected. The results of the study of mathematical models implemented in the selected software system will allow not only to get an idea of the thermal process occurring during electron beam welding of thin-walled products, as such, but also to form a mathematical justification for making technological and control decisions.
Cryopreservation of mesenchymal stromal cells (MSCs) and MSCs-based tissue engineered constructs (TECs) is a promising strategy for regenerative medicine.
To examine vitrification system consisting ...of multicomponent vitreous solution, closed type container, human adult MSCs and two-step exposure procedure as a platform for cryopreservation of MSCs-based TECs.
Vitrification properties of solutions were studied by visual analysis and calorimetry. Viability (trypan blue, MTT-test), metabolic activity (Alamar Blue assay) and adhesion of cells were assessed both after exposure with vitreous solutions and following rapid cooling-thawing in standard cryovials.
The feasibility of the vitrification system was tested on MSCs suspensions (S-MSCs) and alginate encapsulated MSCs (AE-MSCs). The minimal concentrations of cryoprotectants, which allowed avoiding ice formation during rapid cooling and rewarming comprised 10 % for dimethylsulfoxide, 20 % for ethylene glycol, 20 % for 1.2-propanediol and 0.5 M sucrose. To achieve viability and metabolic activity rates of AE-MSCs comparable to S-MSCs after vitrification the extension of the exposure time within the same vitreous solution was sufficient. After vitrification both S-MSCs and AE-MSCs retained the capacity to osteogenic and adipogenic differentiation.
Data demonstrate that this vitrification system can be used as a platform for development of effective protocols for cryopreservation of MSCs-based TECs.
Automation of the petrochemical industry has not lost its relevance for a long time, despite the numerous solutions found in this area. The issues of increasing the accuracy indicator, reducing ...costs, increasing profitability and, importantly, ensuring the safety of petrochemical production are still awaiting a technological solution. The article touches upon the aspects of the harmful environment of the working area, the explosion and fire hazard of substances, the complexity of the chemical processes and their sensitivity to deviation from predetermined modes. The article proposes to solve a number of these problems by creating an automated workplace for a laboratory assistant. The article presents monitoring of laboratory process control.
In this paper, we researched the influence of the electron beam defocus on the quality of the weld. The carried-out research was based on the theory of the thermal field using mathematical models ...developed by the authors. As a criterion of optimality, the previously developed thermal functional was used. We obtained criteria that can be used to simulate processes in electron beam welding, and to obtain more accurate modes, which is necessary to bind to power equipment. The obtained results of the criteria can be used for electron beam welding of various materials and different thicknesses.
The article describes the development of the software system for selecting the main modes of the diffusion welding technological process, with the implementation of the antifriction coatings based on ...fluoroplastics. The description of the algorithms for determining the main technological regimes from the entered necessary values of the tensile strength and wear rate, working conditions, operating temperature range, and the required composition of the material is given. The choice of the main parameters values of the technological process is made according to the maximum value of the tensile strength and the calculated value of the wear rate. According to the developed algorithm, the current values of the main parameters of the technological process are calculated. In case of insufficient strength of the joint or exceeding the value of the wear rate, the technological parameters are adjusted within the established limits or the coating material is replaced. For the decision support system in the design of technological processes, information bases were developed on the existing modes of polymeric materials diffusion welding to substrates of various types, and a database of tribotechnical information. The information database is implemented in a three-purpose software shell: 1) for entering and searching information in the database by fields, 2) for the work of an expert technologist, for linking information fields on topics, technologies, materials, 3) for work in the information mode, and in the mode of issuing an information array for process control. The constructed models and databases made it possible to create an algorithm for automating the diffusion welding process with the definition of the main modes. An algorithm for automating the selection of the diffusion welding main modes has also been developed. For the implementation of the "query generation" unit of the enlarged search algorithm, a production model of knowledge representation was used. As a result of the algorithm, an array of information is transmitted to the following modules of the algorithm. Databases were filled and logical connections of knowledge representation were established.
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