Mathematical Modeling Of Horizontal Displacement Of Above-ground Gas Pipelines

The modern geodetic equipment allows observations as soon as possible, providing high accuracy and productivity. Achieving high accuracy of measurement is impossible without taking into account external factors that create influence on an observation object. Therefore, in order to evaluate an influence of thermal displacement on the results of geodetic monitoring a mathematical model of horizontal displacement of above-ground pipelines was theoretically grounded and built. In this paper we used data of experimental studies on the existing pipelines "Soyuz" and "Urengoy - Pomary - Uzhgorod". Above-ground pipeline was considered as a dynamic system "building - environment". Based on the characteristics of dynamic systems the correlation between the factors of thermal influence and horizontal displacement of the pipeline axis was defined.Establishing patterns between input factors and output response of the object can be useful not only for geodetic control, but also for their consideration in the design of new objects. It was investigated that the greatest influence on the accuracy of geodetic observations can create dispersion of high-frequency oscillations caused by daily thermal displacement. The magnitude of displacement exceeds actual measurement error.The article presents the results of calculation of high-frequency oscillations of above-ground gas pipeline.The result made it possible to substantiate the accuracy and methodology of geodetic observations of the horizontal displacement of pipeline axes taking into account an influence of cyclical thermal displacement.Research results were recommended for use in practice for enterprises that serve the main gas pipelines and successfully tested by specialists of PJSC "Ukrtransgaz" (Kharkiv, Ukraine) during the technical state control of aerial pipeline crossing in Ukraine and also can be used to form the relevant regulations

Mathematical Modeling Analysis for Investigating the Future Expansion of the Electric Power System in Indonesia

Tulisan berikut berisikan ringkasan disertasi doktoral yang berjudul Mathematical Modeling Analyses for Investigating the Future Expansion of the Electric Power System in Indonesia. Studi ini memiliki lima tujuan yaitu (i) menginvestigasi sektor ketenagalistrikan sebelum dan setelah program percepatan 10.000 MW tahap I dan II; (ii) menganalisis hubungan antara pertumbuhan ekonomi dan konsumsi listrik; (iii) menyusun model ekspansi tenaga listrik dalam mencapai tujuan minimisasi biaya pembangkit dan minimisasi emisi CO2; (iv) mengaplikasikan model optimasi sistem pembangkit untuk sistem Jawa-Bali; (v) mengusulkan kebijakan guna mencapai sistem pembangkit listrik yang rendah emisi CO2. Studi ini mengkombinasikan dua pendekatan, yaitu ekonometrik dan program linier untuk menjawab kelima tujuan penelitian tersebut

Numerical method for solving multipoints elliptic-parabolic equation for dehydration process

Drying is the oldest and efficient form of preserving fruits. This research focuses on the mathematical modeling of tropical fruits dehydration using instant controlled pressure drop (Détente Instantanée Controlée or known as DIC) technique. We proposed a modification of mathematical modeling to enhance the previous modeling from Haddad et al. [10]. The mathematical modeling presents the dehydration process of DIC technique which involves parameters such as pressure, water content, time dependency, dimension of region and temperature behavior. The modification of the mathematical modeling has been done by transforming the quadratic equation to partial differential equation (PDE). The simulation of the dehydration process will be illustrated through Jacobi method based on two, three and five points forward difference schemes. The sequential algorithm is developed by using Matlab 7.6.0 (R2008a) programming. The numerical analysis of finite difference schemes in terms of number of iteration, time execution, maximum error and computational cost are compared

Exploring young students creativity: The effect of model eliciting activities

The aim of this paper is to show how engaging students in real-life mathematical situations can stimulate their mathematical creative thinking. We analyzed the mathematical modeling of two girls, aged 10 and 13 years, as they worked on an authentic task involving the selection of a track team. The girls displayed several modeling cycles that revealed their thinking processes, as well as cognitive and affective features that may serve as the foundation for a methodology that uses model-eliciting activities to promote the mathematical creative process

Mathematical modeling of genome replication

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