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PL
Wstęp i cele: W pracy opisano możliwość zastosowania elementów teorii perkolacji w hydrogeologii do modelowania przesączania wody gruntowej przez fundamenty budynków. Celem pracy jest stworzenie analityczno-numerycznego modelu przesączania wody przez fundamenty budynków w aspekcie teorii perkolacji. Materiał i metody: Materiał opracowano na podstawie literatury przedmiotu. Zastosowano metodę analityczną i numeryczną z zastosowaniem programu MathCAD. Wyniki: W pracy przedstawiono model analityczny, w ujęciu macierzowym, natężenia przesączania wody gruntowej przez materiał fundamentu budynku. Opracowano symulację graficzną w aspekcie teorii perkolacji z użyciem algorytmu numerycznego w programie MathCAD. Wniosek: Znajomość wyników symulacyjnych w programie numerycznym z równoczesną analizą badań specjalistycznych geologicznych pozwoli przewidzieć dopuszczalny krytyczny stan nasycenia wodą gruntową fundamentu budynku.
EN
Introduction and aim: The paper presents the possibility of applying the elements of percolation theory in hydrogeology to the modeling of groundwater filtration through the foundations of buildings. The aim of this work is to create an analytical and numerical model of groundwater filtration through foundations of buildings in the aspect of percolation theory. Material and methods: The material is based on the literature of the subject. An analytical and numerical method using MathCAD has been used in the paper. Results: The paper presents an analytical model, in terms of matrix, of groundwater filtration through the building foundation material. A graphical simulation of the percolation theory using numerical algorithms in MathCAD has been developed in the considerations. Conclusion: Knowledge of simulation results in a numerical program with simultaneous analysis of geological research will allow predictable critical groundwater saturation of the building foundation.
PL
Wstęp i cele: W pracy przedstawiono sposób analityczno-numeryczny wyznaczania wartości mocy wydzielanej na próbkach walcowych kompozytowych przez prąd upływnościowy powierzchniowy w ujęciu teorii perkolacji. W przyjętym modelu sformułowano w zapisie macierzowym prąd perkolacji, impedancję i moc wydzielaną na powierzchni próbek kompozytowych. Celem pracy było wyznaczenie wartości mocy traconej na powierzchni próbek kompozytowych. Materiał i metody: Podstawą opracowania była literatura dotycząca perkolacji. Badania starzeniowe oparto metodzie MGR (ang. Merry-Go-Round) dla próbek kompozytowych. Zastosowano metodę tak analityczno-numeryczną jak i doświadczalną. Wyniki opracowano numerycznie w programie MathCAD. Wyniki: W wyniku obliczeń analityczno-numerycznych uzyskano wartości mocy pozornej wydzielanej na powierzchni badanych próbek kompozytowych. Opracowano graficznie charakterystyki mocy pozornej. Wniosek: Podczas badania starzeniowego próbki kompozytowej metodą MGR, po osiągnięciu progu perkolacji następuje wzrost mocy pozornej wydzielanej na jej powierzchni.
EN
Introduction: Analytical and numerical determination of power occurring on cylinder composite samples by surface leakage current in the aspect of percolation theory have been presented in the paper. In the given model the value of percolation current, impedance and power occurring on the samples have been defined in matrix notation. Some determinations of power in the aspect of percolation theory have been elaborated in the paper. The main aim of the paper is some determination of apparent power values on the surface of composite samples. Material and methods: The basis of the study was literature contained percolation theory. The study was based on aging method MGR (Merry-Go-Round) for composite samples. In the paper have been used not only the analytical and numerical but also some experimental method. The results have been numerically elaborated in the MathCAD program. Results: Using some analytical and numerical calculations have been obtained the values of apparent power emitted on the surface of the tested composite samples. The apparent power characteristics have been graphically elaborated in the study. Conclusion: During the senescence study of the composite sample by MGR method, after reaching the percolation threshold there is an increase apparent power emitted on its surface.
EN
The paper discusses possible applications of the percolation theory in analysis of the microstructure images of polycrystalline materials. Until now, practical use of this theory in metallographic studies has been an almost unprecedented practice. Observation of structures so intricate with the help of this tool is far from the current field of its application. Due to the complexity of the problem itself, modern computer programmes related with the image processing and analysis have been used. To enable practical implementation of the task previously established, an original software has been created. Based on cluster analysis, it is used for the determination of percolation phenomena in the examined materials. For comparative testing, two two-phase materials composed of phases of the same type (ADI matrix and duplex stainless steel) were chosen. Both materials have an austenitic - ferritic structure. The result of metallographic image analysis using a proprietary PERKOLACJA.EXE computer programme was the determination of the content of individual phases within the examined area and of the number of clusters formed by these phases. The outcome of the study is statistical information, which explains and helps in better understanding of the planar images and real spatial arrangement of the examined material structure. The results obtained are expected to assist future determination of the effect that the internal structure of two-phase materials may have on a relationship between the spatial structure and mechanical properties.
4
Content available Structure Modelling Based on Percolation Theory
EN
The paper discusses the possibility of application of percolation theory to model the structure of materials in a virtual space. The designed models were transferred to real space using modern incremental manufacturing techniques like 3D printing. Studies of model materials of this type based on percolation theory are expected to provide more accurate knowledge of the problem, which is extremely important from the point of view of the properties of most construction materials. Reference of percolation phenomena to materials science is more and more frequently done in the design of various types of composite materials, such as e.g. conductive composites. In this study, the percolation theory has been used to design in microscale an optimum material through model analysis done in macroscale. Since studies of percolation in polycrystalline materials are difficult, and there are also some technical limitations imposed on the evaluation done in a volume of material, this phenomenon is usually examined in a simplified manner, which means that it is reduced only to statistical analysis of potential percolation with determination of its threshold value. To generate a potential structure based on percolation theory, popular computer programmes for solid modelling were used. Real shapes were conferred to the designed models using a widely known technique of 3D printing. It allows the production of parts in ABS material. The subject of the present study combines modern design techniques with modern manufacturing techniques, relating both to the fundamentals of materials science. Today's software tools enable creating more complex solids, while their transfer to reality allows better understanding of dependencies that exist in the structure of materials. The originality of this study consists in the art of creating new construction materials with planned properties. The article offers a new approach to the capabilities of scheduling modern engineering materials with the help of percolation theory.
EN
As the MANET topology send so excessive RREQ packets, we propose an improved AODV algorithm based on probability broadcasting with percolation theory, and select the critical threshold of network connectivity as the forwarding probability in the processing in routing discovery of AODV. We retain historical routing information and record the numbers of the remaining hops into the hop counter, making RREQ groups forwarding along to the node of the minimum remaining hops, reducing the overlap coverage of the sending signals among the neighboring nodes.
PL
Zaproponowano ulepszony algorytm AODFV (ad hoc on demand distance vector routing) do topologii MANET. Algorytm uwzględnia prawdopodobieństwo transmisji, teorię perkolacji (teorię przecieku) oraz historię połączeń.
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