15 research outputs found
Information Analysis Support for Decision-Making in Scientific and Technological Development
This
paper presents the development of an information and analytical system to
foster scientific and technological development in a given scientific field. In
this work, the main software tools for implementing distributed computing,
which involves a set of software components for collecting, processing, and
analyzing large amounts of data, are considered. In addition, various
approaches for task coordination between different sets of software are
discussed and techniques for storing large amounts of data are described. The
system architecture and database schema are designed and tested. Nowadays, the
intellectualization of individual software agents is a key aspect of a new
generation of multiagent systems. For this reason, this paper develops an
approach that can organize activities of a large number of software agents to
increase system intellectualization through swarm intelligence at the level of
individual agents. Three remote servers were used to build and test the system
deployment, comprising such components as a platform for monitoring and
scheduling workflow, data storage, and a graphical user interface that enables
data retrieval and interaction on the Internet
A recursive sparse grid collocation method for differential equations with white noise
We consider a sparse grid collocation method in conjunction with a time discretization of the differential equations for computing expectations of functionals of solutions to differential equations perturbed by time-dependent white noise. We first analyze the error of Smolyak's sparse grid collocation used to evaluate expectations of functionals of solutions to stochastic differential equations discretized by the Euler scheme. We show theoretically and numerically that this algorithm can have satisfactory accuracy for small noise magnitude or small integration time, however it does not converge either with decrease of the Euler scheme's time step size or with increase of Smolyak's sparse grid level. Subsequently, we use this method as a building block for proposing a new algorithm by combining sparse grid collocation with a recursive procedure. This approach allows us to numerically integrate linear stochastic partial differential equations over longer times, which is illustrated in numerical tests on a stochastic advection-diffusion equation
On the possibility to fabricate ceramics using fused deposition modeling
The paper presents a uniquely designed device that enables controlled manufacturing of semi-fabricated products from thermoplastic ceramic suspensions by fused deposition modeling. Sintering of the products yields ceramics with high strength and hardness. We use ceramic aluminum oxide (Al2O3) as an example to prove that additive ceramic structures can be produced without noticeable boundaries between layers of the material
Multi-stage metamorphic evolution and protolith reconstruction of spinel-bearing and symplectite-bearing ultramafic rocks in the Zheltau massif, Southern Kazakhstan (Central Asian Orogenic Belt)
Wiener chaos versus stochastic collocation methods for linear advection-diffusion-reaction equations with multiplicative white noise
We compare Wiener chaos and stochastic collocation methods for linear advection-reaction-diffusion equations with multiplicative white noise. Both methods are constructed based on a recursive multistage algorithm for long-time integration. We derive error estimates for both methods and compare their numerical performance. Numerical results confirm that the recursive multistage stochastic collocation method is of order (time step size) in the second-order moments while the recursive multistage Wiener chaos method is of order ( is the order of Wiener chaos) for advection-diffusion-reaction equations with commutative noises, in agreement with the theoretical error estimates. However, for noncommutative noises, both methods are of order one in the second-order moments
Anisotropy of Mechanical Properties and Residual Stress in Additively Manufactured 316L Specimens
In the presented study, LPBF 316L stainless steel tensile specimens were manufactured in three different orientations for the analysis of anisotropy. The first set of specimens was built vertically on the build platform, and two other sets were oriented horizontally perpendicular to each other. Tensile test results show that mean Young’s modulus of vertically built specimens is significantly less then horizontal ones (158.7 GPa versus 198 GPa), as well as yield strength and elongation. A role of residual stress in a deviation of tensile loading diagrams is investigated as a possible explanation. Simulation of the build process on the basis of ABAQUS FEA software was used to predict residual stress in 316L cylindrical specimens. Virtual tensile test results show that residual stress affects the initial stage of the loading curve with a tendency to reduce apparent Young’s modulus, measured according to standard mechanical test methods
On the possibility to fabricate ceramics using fused deposition modeling
The paper presents a uniquely designed device that enables controlled manufacturing of semi-fabricated products from thermoplastic ceramic suspensions by fused deposition modeling. Sintering of the products yields ceramics with high strength and hardness. We use ceramic aluminum oxide (Al2O3) as an example to prove that additive ceramic structures can be produced without noticeable boundaries between layers of the material