A review of the problem of accounting for random factors in the scheduling of construction projects is considered. The problems of taking into account random factors in construction scheduling have been considered in works. However, these studies have not paid full attention to the course of construction for large projects. At the same time, scheduling problems are closely related to optimization of working hours and resource allocation in construction production. Such tasks are usually solved by considering several variants of the technological sequence of works, and the typology and variability of random factors are not fully taken into account. A number of researchers have the view that the determining factor in estimating the actual duration of construction is the reliability of suppliers and delivery of construction products. However, it is not possible to ensure the construction process in reality without interruptions in work. The main reason for this is random factors. It is suggested to take them into account on the basis of modern information technologies including artificial intelligence, stochastic approaches, probability theory and mathematical statistics.
Keywords: Construction organisation, random factors, organisational expectations, calendar modelling, stochastic search, genetic algorithms
This paper presents a simulation of the vibrations of a membrane in the form of a rhombus. Partial solutions of the problem of free vibrations of a membrane with different initial conditions are obtained and the natural frequencies of vibrations are found. The result obtained can be used to strengthen the structural elements of aircraft with a cellular diamond-shaped structure, as well as in the design of unmanned drones of the flying wing type.
Keywords: free vibrations of a membrane, a membrane in the shape of a rhombus, natural frequencies of vibrations
The problem of physical deterioration values of residential buildings for a given period of time for practical purposes is considered. A review of the existing normative and technical documents for determining the physical deterioration of residential buildings has been carried out. Various methods for predicting physical deterioration for a given period of time are considered. The conclusion is made about a linear increase in physical deterioration with an average annual increase of 1%. Recommendations are given on the use of the data obtained in the planning of operational measures for the repair and maintenance of residential buildings .
Keywords: predicting, physical deterioration, residential building, building management, average annual increase, technical inspection, chronological age method, expert method, service life, technical condition assessment
Effective reinforcement of the coating beam, by means of the construction of a framing frame around it, implies a reasonable choice of a construction from a range of rolled metal. The frame creates a single system with the coating beam by means of tension devices, the change of forces in which provides state control. In the article, a comparative analysis of moments in a frame made of an I-beam and a special steel channel, as having potentially equal performance characteristics, is proposed for a comparative study. The research was carried out on the basis of numerical modeling by the finite element method using the Etabs software product. The result of the experiment was the transverse forces and moments determined in the newly formed system – the coating beam plus the frame – from the applied loads and the percentage of reinforcement of the beam when taking into account the frame. The array of numbers obtained as a result of the numerical experiment was processed by digital mathematical analysis.
Keywords: reinforced concrete beam, I-beam reinforcement, channel reinforcement, moment, percentage of reinforcement, load, numerical method, mathematical model, comparison of results, Etabs and wxMaxima software packages
An overview of methods for assessing the state of the environment is presented. The study of methods for assessing the state of the environment and the impact of production facilities is the most important factor contributing to reducing the negative impact on the environment. An example of a comprehensive assessment of atmospheric air in the Motovilikhinsky district of Perm using the Jobs-Decon software package is considered.
Keywords: ecology, environment, subject-oriented management, production facilities, assessment, Jobs-Decon, environmental pollution
The tasks of preparing for the modernization of the automatic pressure control system with the transition from the use of a PD controller in favor of a PID controller and the introduction of a controlled electric fan drive in a boiler plant are being solved. A technique for constructing a fan model in the automatic control system for air supply to the boiler is given using the example of a VD-18 blower fan and a BKZ-160 boiler. The block diagram of the operation of the fan and pipeline is given. A mathematical model of the fan is shown, a calculation is made and a computer model is designed in MATLAB Simulink. The simulation results are presented, which prove the correctness of the obtained model. The presented model can serve as a basis for automating the air supply system in other boilers using blowers.
Keywords: automatic pressure control system, automatic control system, dynamic model, computer model, blower fan, boiler plant
This paper describes the development of a recommender system for the selection and configuration of deep neural network models. Her key area of work is evaluating the effectiveness of a neural network for a particular type of problem. The recommender system designed within the framework of the repository allows for precise search, selection and flexible configuration of neural networks depending on specific project-oriented tasks.
Keywords: recommender system, machine learning, deep learning, neural network model, expert system, neural network, repository, spatial data, geographic information system, configuration, architecture
The problem of human self-knowledge is very relevant nowadays. People are constantly looking for new methods to study their own “I”. Graphology is one of such methods. The main difficulty of graphological analysis is the lack of automation of the process, the result depends only on the knowledge of the person. In addition, at the moment there is no service capable of carrying out a competent analysis of a person's handwriting. However, there are computer vision methods that, in combination, can produce work similar to that of a graphologist. Such methods include segmentation, binarization, and integral estimation methods. To compare the characteristics of handwriting with human characteristics of character, it is necessary to use classifiers. The use of all methods makes it possible to create a service that automates graphological analysis.
Keywords: graphology, handwriting, personal characteristics, graphological analysis, slope, direction of handwriting, text
In this paper, based on Russian and foreign experience in mathematical modeling of photovoltaic installations, the authors consider the approaches to the construction of these models. The relevance of the research is confirmed by the wide spread of electric energy sources using solar energy. The scheme of photovoltaic element substitution and the dependences describing the processes occurring in it are given. The authors conclude that despite the large number of various mathematical models of photovoltaic elements, all of them can be grouped into two categories. The first category includes models that consider photovoltaic panels as a separate element, and the second category includes models where the photovoltaic panel is a component of a generating complex. Despite the difference in the analyzed approaches, the authors single out a number of parameters that characterize the operation of a photovoltaic panel and are sufficient to obtain simulation results with the required accuracy.
Keywords: photovoltaic panel, mathematical modeling, substitution scheme, distributed generation, power generation
In a market economy, it is required to calculate foundations using methods that will satisfy the requirements of the first and second limit states with the smallest margins, in order to save money. In this study, the analysis of sediments obtained by numerical and analytical methods was carried out. Analytical calculation is presented by the method of corner points according to the model in the form of a linearly deformable half-space and by the method of layer-by-layer summation presented in the form of modified Pasternak, Winkler-Fuss, Pasternak models. The numerical method is presented by the finite element method implemented in the software systems of the PC «Lira-SAPR» and the PC «PLAXIS 3D». As a result, it was found that the minimum discrepancy between the absolute settlement according to the corner point method in comparison with the analytical method according to the Winkler-Fuss, Pasternak, modified Pasternak models is 9.04%, 9.04%, 53.38%, respectively, and in comparison with the numerical method implemented in the PC «Lira-SAPR» and PC «PLAXIS 3D» is 10.49% and 0.52%, respectively. The highest accuracy in comparison with the method of corner points was shown by analytical calculations by the method of layer-by-layer summation in the formulation of Winkler-Fuss and Pasternak, and by the numerical method of calculation performed by the PC "PLAXIS 3D".
Keywords: geotechnics, foundations, «Lira-SAPR», system «Soil», «PLAXIS 3D», foundation sediment, angular point method, slab foundation, mutual influence of foundations, numerical method, analytical method, finite element method
Relevance and goals. The article is devoted to the description of the results of the development process of the geoinformation web portal "Interactive map " Natural and cultural heritage of the Republic of Mordovia. We travel with the Russian Geographical Society"", which implements the functionality of access to a digital map with a layered systematized display of spatial data on objects of natural and cultural heritage of the region. Materials and methods. The implementation of the metageosystem concept in the development of tourism and recreational development projects is based on the broad involvement of paleogeographic, landscape, archaeological, historical, ethnographic, demographic, cultural, environmental and economic information in the research process. Results. During the development of the geoportal "Natural and cultural heritage of the Republic of Mordovia. Traveling with the Russian Geographical Society" solved the problem of creating a new subsystem for visualizing geospatial data for a digital map based on modern web technologies. Conclusions. The developed geoportal system solves the problem of managing the tourist and recreational development systems of the region by implementing the concept of forming an interactive spatial data management tool.
Keywords: geoportals, cultural landscape, spatial data infrastructure, management in organizational systems, spatial data, decision making
The wastewater generated by the pulp and paper industry contains diverse contaminants such as organic substances, fine suspended powders, and dissolved solids. Currently, integrated treatment technologies are employed, utilizing thin-layer settling tank modules to eliminate solid contaminants. This study presents the outcomes of a comparative analysis of the efficacy of a conventional thin-layer module with flat plates and a modified thin-layer module consisting of two levels of plates, positioned in opposing directions, facilitating the rotation of water flow within the module. Through computer simulation techniques, it is demonstrated that the modified module design can enhance the cleaning efficiency by 8-30% for wastewater flow velocities ranging from 0.0025 to 0.0125 m/s. Additionally, particle trajectories and velocity fields were obtained, which clearly illustrate the direction of the dictating flow and circulation zones within the structure.
Keywords: Wastewater, pulp and paper industry, thin-layer module, module with rotation of water flow, computer simulation of particle deposition.
The article contains an analysis of the shallow elastic spherical shell on a rectangular plan, reinforced with ribs along its contour, under the uniformly distributed load. The problem is solved numerically with the variational-difference method, considering the geometric nonlineaity and the shear deformations of the shell and the ribs. As a result, the dependencies of the critical load on the shell stiffness and the ribs stiffness are obtained.
Keywords: shallow spherical shell, ribbed shell, stability, bending stiffness, geometrical nonlinearity, variational-difference method, critical load
The article presents a study of accidents on the roads involving children and persons under the age of majority. An analysis was made of the legal norms for the protection of the rights of the child on the roadway. In addition, an additional means of reducing accidents on the roads, as well as its location relative to the pedestrian, was identified.
Keywords: accident, traffic accident, child, children, incident, road, section, pedestrian
This article discusses the relationship of all stages of the life cycle of buildings on the basis of information-analytical system IAS HCS. The full life-cycle cost of a 1,000-seat school was calculated. Using the IAS HCS program, we made calculations of the costs of repair work on three models: without taking into account any repair work, taking into account the repair of the main structural elements and taking into account the repair of all elements, based on the standard operating time. Real estate life cycle cost analysis can be performed for both new and existing buildings of any type (residential and public). Evaluation of the total costs of the full life cycle of the object can be applied by both the developer and the owner of the building to further improve the management system of the property.
Keywords: lifecycle of construction object, information modeling, social facilities, cost of repair work, replacement cost