Nowe zasoby w kolekcji Materiały konferencyjne http://suw.biblos.pk.edu.pl/ Biblioteka Politechniki Krakowskiej lipinska@biblos.pk.edu.pl 60 <![CDATA[Intelligent computing in optimization of coupled problems]]> Tue, 24 Nov 2020 10:17:20 +0100 Burczyński, T.; Długosz, A.
rodzaj: materiały konferencyjne w książce
Abstrakt: This paper proposes a multiobjective optimization approach for designing selected coupled-field models. The optimization method is based on evolutionary algorithm (EA). Proposed technique overtakes one of the most popular multiobjective evolutionary algorithm NSGAII [5,6] on several benchmark and engineering problems. Coupling between electrical, thermal and mechanical fields is considered. Finite element method (FEM) is used to simulate direct coupled problems numerically. The software packages based on FEM are adapted to create the optimization system. Suitable interfaces between optimization algorithm and the FEM software are created. They use internal script languages embedded in preprocesors of the FEM systems. Different types of functionals are formulated on the basis of the results obtained from coupled-field analysis. Functionals depending on the volume of the structure are also proposed. Parametric NURBS curves are used to model some optimized structures. Numerical examples for bi-objective and three-objective optimization problems are presented.]]>
<![CDATA[The effect of use E85 ethanol fuel on a five-stroke engine]]> Mon, 23 Nov 2020 15:15:10 +0100 Noga, M.
rodzaj: materiały konferencyjne w czasopiśmie
Abstrakt: The article presents the analysis of the impact of the use of E85 ethanol fuel on operating parameters and toxicity of exhaust gases of a spark ignition engine with an additional expansion in a separate cylinder. Such an engine in literature most often referred to as five-stroke was developed at the Cracow University of Technology (CUT). The use of additional exhaust expansion was aimed at achieving high thermal efficiency when working with an average high load. The engine developed in CUT is equipped with a turbocharger and direct fuel injection, hence the use of fuel with high ethanol content was aimed at the effective use of these attributes. The obtained results indicated an improvement in the brake thermal efficiency of the engine when fueling with E85 in relation to the gasoline of 98 octane rating normally used for this engine. On the other hand, the efficiency of the conversion of the catalytic converter has deteriorated somewhat. Directions for further activities and research in the subject were also determined.]]>
<![CDATA[Comparison of chosen gasification systems for solid fuels and biomass in termsof obtaining hydrogen for small application]]> Mon, 23 Nov 2020 15:07:10 +0100 Mitianiec, Władysław
rodzaj: materiały konferencyjne w książce
Abstrakt: Current requirements concerning the clean combustion technology both in automotive sector and energy industry force to search fuels with small molar concentration of carbon and sulphur. One of the best methods to obtain gaseous fuels is gasification of solid fuels and biomass together with municipal sewage. Dispersion of energy production requires smaller gasification reactors for local applications. The paper presents various small gasification systems with water-coal mixture and water-biomass mixture both with oxygen (air) and without oxygen. Mathematical modelling together with 13 kinetic chemical reactions enabled to apply them in CFD program. The chemical model is based on surface reactions given in the model of Equivalent Reactor Network (ERN) in Ansys Energetico . Simulation of gasification of different reactor designs enabled to obtain the mass concentration of chemical compounds on the outlet of the system. The work includes also general flow of the fluid inside gasifier. Increasing of internal turbulence inside the gasification system gives better and quicker gasification process than in the stationary flow about 30%. Additionally, heating of the gasifier walls by electrical system without air gives higher mass ratio of hydrogen (0.13) and carbon monoxide (0.55) at the outlet than in the system with the air. The air consumes some part of the fuel and a lot of carbon dioxide is produced. The paper shows comparison of mass concentration of CO, H2, H2O, H2S, CO2, O2, CH4, tar, C(s) and other chemical compounds in the syngas for solid fuels and municipal sewage. Computation of different gasification systems enabled to choose the best system to obtain higher concentration of hydrogen in the syngas. Generally, turbulence and internal heating of the water-fuel mixture enables higher concentration of hydrogen in the syngas. Application of the gasification reactor with external heated walls and without oxygen inflow produces the syngas without tar and volatile species in comparison to the systems with additional oxygen supply. In all considered cases the syngas contained a large amount of CO2 about 25 – 30% of total mass. Such system will be used in one of polish small enterprise for fuelling of special industrial piston engine. This article is the result of research work carried out in the project financed by polish National Centre of Research and Development. ]]>
<![CDATA[About the solutions to the Witten–Dijkgraaf– Verlinde–Verlinde associativity equations and their Lie-algebraic and geometric properties]]> Fri, 20 Nov 2020 14:55:31 +0100 Prykarpatski, Anatolij K.
rodzaj: materiały konferencyjne w książce
Abstrakt: There is devised an algebraically feasible approach to investigatingsolutions to the oriented associativity equations, related with commutativeand isoassociative algebras, interesting for applications in the quantum de-formation theory and in some other fields of mathematics. The main con-struction is based on a modified version of the Adler–Kostant–Symes scheme,applied to the Lie algebra of the loop diffeomorphism group of a torus andmodified for the case of the Gauss–Manin displacement equations, dependingon a spectral parameter. Their interpretation as characteristic equations forsome system of the Lax–Sato type vector field equations made it possible toderive the determining separated Hamiltonian evolution equations for the re-lated structure matrices, generating commutative and isoassociative algebrasunder consideration.]]>
<![CDATA[Performance optimization of edge computing homeland security support applications]]> Wed, 18 Nov 2020 13:12:55 +0100 Gribaudo, Marco; Iacono, Mauro; Jakóbik, Agnieszka; Kołodziej, Joanna
rodzaj: materiały konferencyjne w książce
Abstrakt: Critical distributed applications have strict requirements over performance parameters, that may affect life of users. This is a limitation that may prevent the exploitation of cost effective solutions such as Cloud Computing (CC) based architectures: in fact, the quality of the connection with the CC facility and the lack of control on cloud resources may limit the overall performances of an application and may cause outages. A way to overcome the problem, and disclose the advantages of CC to critical applications, is provided by Edge Computing (EC). EC adds local support to CC, allowing a better distribution of application tasks according to their timeliness requirements. In this paper we present an innovative Special Weapons And Tactics (SWAT) support application, designed to empower effective operations in wide scenarios, that leverages EC to join CC elasticity and local immediateness, and we exploit Queuing Networks (QN) and Genetic Algorithms (GA) to design and optimize the system parameters for an effective workload distribution.]]>
<![CDATA[Stackelberg game-based models in energy-aware cloud scheduling]]> Wed, 18 Nov 2020 13:11:12 +0100 Fernández-Cerero, Damián; Fernández-Montes, Alejandro; Jakóbik, Agnieszka; Kołodziej, Joanna
rodzaj: materiały konferencyjne w książce
Abstrakt: Energy-awareness remians the important problem in today’s cloud computing (CC). Optimization of the energy consumed in cloud data centers and computing servers is usually related to the scheduling problems. It is very difficult to define an optimal scheduling policy without negoative influence into the system performance and task completion time. In this work, we define a general cloud scheduling model based on a Stackelberg game with the workload scheduler and energy-efficiency agent as the main players. In this game, the aim of the scheduler is the minimization of the makespan of the workload, which is achieved by the employ of a genetic scheduling algorithm that maps the workload tasks into the computational nodes. The energy-efficiency agent selects the energy-optimization techniques based on the idea of switchin-off of the idle machines, in response to the scheduler decisions. The efficiency of the proposed model has been tested using a SCORE cloud simmulator. Obtained results show that the proposed model performs better than static energy-optimization strategies, achieving a fair balance between low energy consumption and short queue times and makespan.]]>
<![CDATA[Behaviour of fly ash geopolymer at high temperature]]> Mon, 16 Nov 2020 09:02:26 +0100 Hager, Izabela; Sitarz, Mateusz; Mróz, Katarzyna
rodzaj: materiały konferencyjne w czasopiśmie
Abstrakt: Geopolymer is an inorganic mineral binder in several applications an alternative to Portland cement. The driving force for the utilisation of geopolymers is their ability to consume industrial residues and by-products with the great potential to reduce mine tailings and industrial by-product piles. The study presents test results concerning the impact of high temperature on physical and the mechanical properties on fly ash geopolymers with different partial replacement of fly ash (FA) by ground granulated blast furnace slag (GGBFS). The objective of this study is to clarify the influence of high temperature up to 1000°C on the course of physical and mechanical properties changes in the further perspective to their application as passive fire protection material. Although the GGBFS addition has a very beneficial effect on the strength of geopolymer giving compressive strength over 100 MPa, at high temperature, unblended FA behaves much better. An increase in compressive strength was observed after heating at 200°C and 400°C. Moreover, at 1000°C a stage of strength recovery was observed.]]>