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Number of results: 9
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Abstract

In this paper, the definitions of the space and projection systems, used in the mathematical model, have been shown. The projection system, situation of the plane and the projection centre have been established. The concept of the model of perspective projection process has been described: the stages of the geometrical data process (3D objects included in Electronic Navigation Chart- ENC) realized during projection process. Separately were considered the issues of changing of the reference plane and the projection centre with respect to the geocentrical reference system and movement of the ship as the geometrical object containing the reference system. They constitute a basis for preparing the conception of connecting the moving ship with the observer reference system using three established, nonlinear points (with known position with respect to the geocentrical reference system) placed on ship's board and with the horizontal topocentric reference system.
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Authors and Affiliations

Krzysztof Naus
Artur Makar
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Abstract

Electric energy systems need constant modernization and updating to solve such problems as distributed management, self-sealing, improving the quality of electricity, demand management, and integration of renewable energy systems. Currently, energy systems need advanced and intelligent technologies to perform various system-level tasks. The purpose of this research is to analyze the existing control systems of electric energy systems, as well as to consider the possibility of using multi-agent systems to control electric energy systems. To achieve the aim of the research, the following scientific approaches were implemented: method of direct research, experimental method, questioning, comparative method, analysis method, and method of observation. The primary value of the research is in the novelty of the work and the fact, that functional components in multi-agent systems act as independent agents, which can interact with each other through a message communication system. This provides a simple connection between the components, which can benefit complex systems designed for an intelligent network. The intelligent network provides an efficient energy management system, and the modernization of the existing power system using a multi-agent system provides solutions to many problems. The best implementation of a multi-agent system can be achieved through the employment of fast and protected communication protocols. The authors of the research have conducted research and presented key statistical data on electricity usage in Kazakhstan over the past few years. The practical significance of the research is determined by the applied results, and their scientific significance, which is conditioned upon the use of deep, modern mathematical results and the development of an optimal control system. This research is a part of a universal model and optimal system of emergency quick response, conducting a quick preliminary prognosis as well as ensuring more lasting planning in electricity consumption.
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Authors and Affiliations

Saltanat Bitimanova
1
Aliya Shukirova
1

  1. Department of Systems Analysis and Management, L.N. Gumilyov Eurasian National University, Kazakhstan
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Abstract

The paper concerns the use of limit value of siliceous fly ash content in concrete structures, with the application of various types of cements - based on the current standards and taking into consideration the requirements concerning current exposure classes. The conclusions were based on a review of literature, the results of scientific research, conclusions from expert opinions and buildings and structures supervision reports. In summary, it has been concluded that the use of limit content of siliceous fly ashes may result in negative changes in the properties of composites, which should be ruled out or confirmed by appropriate tests, taking into account the precisely defined composition of concrete, cement and the applied additives and admixtures. It has been emphasised that the problem concerns composites with the increased and limit values of fly ash content, especially as regards cements with the lowered content of clinker and high content of additives and admixtures (affecting the physical and mechanical properties of cement composites). Attention has been drawn to the need to modify the exposure classes, to focus on the requirements concerning the properties of concrete and not the composition - in order to achieve the expected durability.
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Authors and Affiliations

Dominik Logoń
1

  1. Wrocław University of Science and Technology, Faculty of Civil Engineering, pl.Grunwaldzki 11, 59-377 Wrocław, Poland
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Abstract

Over the recent years, there is a growing interest in concrete prefabrication. Many of the currently operating concrete plants have implemented systems that increase the quality of manufactured products, have expanded highly automated production lines and have clearly reduced wastes and energy consumption. However, one of the problems often encountered in the construction industry is the inefficient organization of logistics processes. Proper shipments planning of aggregates consisting of the selection of their appropriate quantity and the aggregate stock, corresponding to the needs of concrete plants should contribute to lowering costs. Therefore, it is necessary to carry out the optimization, the aim of which is to minimize costs, as well as to maximize the fulfillment of the degree of expected needs of concrete plants. This paper presents a model that allows purchase strategy optimization of aggregates with different grain size fraction. For research purposes, three separate aggregate stocks and five different concrete plants are considered.

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Authors and Affiliations

A.K. Nicał
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Abstract

Węgiel kamienny wydobywany w kopalni (węgiel surowy) tworzy substancja organiczna i mineralna. Przed bezpośrednim wykorzystaniem urobek musi być poddany procesom wzbogacania. Stosowane procesy wzbogacania mają na celu usunięcie skały płonnej, pirytu, a także przerostów. Do wzbogacania węgla kamiennego stosowane mogą być zarówno metody wzbogacania na mokro, jak i na sucho. W pracy przedstawiono wybrane ekologiczne i ekonomiczne aspekty procesu suchego odkamieniania węgla kamiennego przy wykorzystaniu separatora powietrzno-wibracyjnego i separatora optyczno-rentgenowskiego. Zastosowanie nowoczesnych urządzeń do suchego odkamieniania, tj. separatory powietrzno-wibracyjne i separatory optyczno-rentgenowskie, umożliwią obniżenie emisji pierwiastków ekotoksycznych ze spalania węgla kamiennego. Wydzielenie pirytu pozwala na obniżenie zawartości siarki, a także innych pierwiastków ekotoksycznych, m.in. rtęci, arsenu, talu, czy ołowiu. Generalnie pod względem ekonomicznym technologia suchego odkamieniania cechuje się niższymi nakładami inwestycyjnymi i kosztami eksploatacyjnymi w porównaniu do metod wzbogacania na mokro. Instalacje suchego odkamieniania są dobrym rozwiązaniem dla inwestycji o krótkim okresie planowanej eksploatacji i/lub dla instalacji o małej wydajności, a także w przypadku ograniczonej dostępności do wody. Dla instalacji o dłuższym okresie eksploatacji i o wyższych wydajnościach, efektywność inwestycji jest wyższa dla metod wzbogacania na mokro. Istnieje również możliwość suchego odkamieniania węgla na dole w kopalni przy użyciu tzw. kruszarek Bradforda. Wydzielony produkt w postaci grubych kamieni może znaleźć zagospodarowanie na dole kopalni, np. do podsadzania wyrobisk.

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Authors and Affiliations

Tadeusz Dziok
Ireneusz Baic
Andrzej Strugała
Wiesław Blaschke
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Abstract

In the years I 999-2002 bryological investigations were carried out within the ,,Morzyk" (Jasienica commune, Bielsko-Biała district) and ,,Skarpa Wiślicka" (Skoczów commune, Cieszyn district) nature reserves located in the western part of Silesian Foothills. The area under study covers 11.47 ha (,,Morzyk") and 24.17 ha (,,Skarpa Wiślicka"). In both studied areas deciduous forests (mainly Den/ario glandulosaeFagetum, Tilio-Carpinetum and Carici remotae-Fraxinetumi predominate. As a results of this research, the occurrence of 11 taxa of liverworts and 69 taxa of mosses have been noted (7 liverworts in ,,Morzyk" and 9 in ,,Skarpa Wiślicka" as well as 51 mosses in ,,Morzyk" and 57 in ,,Skarpa Wiślcka"). The analysis of the frequency range shows, that overwhelming majority of the bryoflora consists of very rare taxa ("Morzyk" - 50%; "Skarpa Wiślicka" - 50%). The most important components of the flora are new or rare for this area bryophytes, such as: Brachythecium campestre, Bryum klinggraeffii, Fissidens exilis, F. gracillifolius, Homomallium incurvatum, Orthodicranum tauricum, Riccio rhenana and Taxiphyllum wissgrillii. Six main ecological groups of species are characterised in detail.
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Authors and Affiliations

Adam Stebel
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Abstract

The paper presents a new method for simultaneous tracking of varying grid impedance and its uncertainty bounds. Impedance tracking consists of two stages. In the first stage, the actual noise estimate is obtained from least squares (LS) residua. In the second stage, the noise covariance matrix is approximated with the use of residual information. Then weighted least squares (WLS) method is applied in order to estimate impedance and background voltage. Finally uncertainty bounds for impedance estimation are computed. The robustness of the method has been verified using simulated signals. The proposed method has been compared to sliding LS. The results have shown, that the method performs much better than the LS for all considered cases, even in the presence of significant background voltage variations.

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Authors and Affiliations

Dariusz Borkowski
Szymon Barczentewicz
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Abstract

This article discusses an integrated concept of sustainable building and of Building Information Modelling (BIM) by means of implementation of the Green BIM management method. Apart from presenting this innovative project management method with particular attention paid to solutions applied by Scandinavian enterprises, the article aims at analysing institutional conditions regarding application of the Green BIM within Polish construction companies. Arguments presented in the article are based on results of a scientific review and industry specific publications. Moreover, the article discusses case studies of projects completed with the implementation of the Green BlM method.

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Authors and Affiliations

K. Araszkiewicz

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