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Number of results: 185
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Abstract

Recently, the search for new effective energy production solutions has been focused on the production of electricity using renewable and environmentally friendly carriers. This resulted in an increased interest in PV cells and cogeneration systems. The article looks at the main factors affecting their operational parameters against the background of the development history of subsequent generations of PV cells. Average daily solar radiation and wind velocity in Lodz were characterized. The research was done on a static and tracking system with a total peak power of 15 kWp and a 30 kW microturbine. PV panels are installed on the building of the Institute of Electrical Power Engineering of the Lodz University of Technology and they work as part of DERLab. A microturbine is inside the building. Energy measurements were carried out in 2016 giving grounds for the analysis of energy efficiency and financial analysis of the energy supply in buildings. Energy yields in the static and tracking system as well as percentage coverage of electricity from PV cells and microturbines were assessed. The distribution of monthly savings, annual savings of energy costs and the payback time of the investment costs of the systems subject to the test were determined. The research we have done allows us to say that the energy produced by follow-up modules is about 3 times greater than that generated in stationary modules. On the other hand, the annual savings of energy costs using gas micro-turbines are about 10 times higher than those of lagging panels. The analysis shows that it is possible to determine the profitability of the microturbine and photovoltaic panels use despite large financial outlays. The payback period of investment outlays is about 12 years when using the installation throughout the year.
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Abstract

Artykuł przedstawia zmiany w polskim prawie dotyczącym odnawialnych źródeł energii w 2016 roku w stosunku do dużych instalacji komercyjnych oraz wpływ tych zmian na opłacalność inwestowania w technologie energetyki odnawialnej ze szczególnym uwzględnieniem energii słonecznej. Porównano dwa systemy wsparcia: oparty na zielonych certyfikatach oraz system aukcyjny. Omówiono w szczególności mechanizm ustalania ceny w systemie aukcyjnym i jego wpływ na opłacalność inwestowania w technologie fotowoltaiczne. Zaprezentowano dyskusję wyników w świetle rozwiązań praktykowanych w innych państwach. Wnioski dotyczą wpływu planowanych zmian na rozwój sektora odnawialnej energii w Polsce.
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Abstract

This article presents a hybrid control system for a group of mobile robots. The components of this system are the supervisory controller(s), employing a discrete, event-driven model of concurrent robot processes, and robot motion controllers, employing a continuous time model with event-switched modes. The missions of the robots are specified by a sequence of to-be visited points, and the developed methodology ensures in a formal way their correct accomplishment.
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Abstract

The rules and guidelines for integrated pest management specified in Annex III, sections 2 and 3, state “General principles of integrated pest management”: Harmful organisms must be monitored by adequate methods and tools, where available. Such adequate tools should include observations in the field as well as scientifically sound warnings, forecasting and early diagnostic systems, where feasible, as well as advice from professionally qualified advisors. As part of Multiannual Programs, the Institute of Plant Protection – NRI in Poznań has been carrying out work and research for many years to develop or modify guidelines for monitoring short- and long-term forecasting of pest occurrence on crops. These guidelines are extremely helpful for farmers and advisers in determining the optimum date of chemical control of pests on plants. Regularly revised and improved the guidelines deal with pests which currently pose a threat to crops. They are developed according to the latest scientific findings and are successfully promoted among professional users and agricultural advisors. These guidelines are standardized to include descriptions of species, life cycles, symptoms of damage/infestation of crops, methods of observation targeted at warning of the need for plant protection treatments, and threshold values of harmfulness. All guidelines include extensive photographic material. Guidelines for the monitoring of pests on orchard plants, vegetables and others are prepared at the Institute of Soil Science and Plant Cultivation − NRI in Puławy and the Institute of Pomology in Skierniewice. Guidelines for about 80 pests of crops are available for public use in the on-line Pest Warning System (Platforma Sygnalizacji Agrofagów, www.agrofagi.com.pl).
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Abstract

The main aim of this paper is to propose a terminological approach to the standardization of onomastic terminology. Attention is paid to the primary importance of conceptual systems and to the onomasiological approach typical of terminological work. Terminology is presented as a discipline devoted primarily to the study of concepts. Then the main concepts of terminology are discussed and the relations between a conceptual system and a terminological system are explained. An outline of the issue of conceptual systems of onomastics and of their internal structure is made. Then two important metatheoretical concepts are introduced and defined: 1) the concept of theoretical legitimacy of concepts and 2) the concept of economy of conceptual systems. In the final part of the article, several suggestions concerning the standardization of onomastic terminology are made: 1) terms referring to concepts belonging to separate conceptual series are not to be used interchangeably; 2) terms based on different roots (in the English onomastic terminology: -onym, -onymy, -onomastics, in the Polish terminology: -onim, -onimia, -onomastyka) are to be reserved respectively for the concept of a single (type of) proper name, for the concept of a set of proper names and for the concept of a specific onomastic discipline; 3) concepts used or newly introduced in a text are to be defined clearly in onomastic works, 4) onomasticians aiming for standardization of onomastic terminology should start their work by (re)constructing conceptual system(s) of onomastics and only then assign terms to concepts; 5) one completely unitary conceptual (and terminological) system of onomastics cannot be achieved due to the theoretical pluralism of the discipline; 6) the first goal of any conceptual and terminological standardization of onomastics is to define its range: should the standardization cover the concepts of philological or general onomastics? should it cover only empirical (descriptive) concepts or highly abstract theoretical concepts as well?
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Abstract

The aim of this study was to determine the effect of the soil tillage system on soil enzymatic activity. The performed investigations, employing two soil tillage systems: classical (ploughing) and simplified (no-tillage), were carried out on Luvisols and Arenosols differing typologically, with regard to their kind and species. The activity of the following five enzymes was determined in soil samples: dehydrogenases, acid phosphatase, alkaline phosphatase, urease and protease. The applied enzymes tests turned out to be good indicators differentiating the examined soil objects depending on the employed tillage system. The employment of the simplified tillage system stimulated significantly the activity of the analysed enzymes irrespective of the soil type. This effect was particularly apparent in the top layer (0-10 cm) of the soil. An exceptionally wide range of activity was obtained for dehydrogenases indicating the usefulness of this group of enzymes for the evaluation of changes in the soil environment under the influence of the soil tillage system. The observed activity stimulation of the examined enzymes was accompanied by advantageous changes in soil chemical conditions.
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Abstract

Necessary and sufficient conditions for robust stability of the positive discrete-time interval system with time-delays are established. It is shown that this system is robustly stable if and only if one well de?ned positive discrete-time system with time-delays is asymptotically stable. The considerations are illustrated by numerical example.
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Abstract

Postulaty poprawy jakości kształcenia nauczycieli wychodzą od wielu środowisk. Krytycznie należy spojrzeć na przygotowanie do zawodu nauczyciela również przez pryzmat doświadczeń ocen programowych i instytucjonalnych Polskiej Komisji Akredytacyjnej. Na podstawie tych doświadczeń, w tekście zaprezentowano modele kształcenia nauczycieli z uwzględnieniem systemu bolońskiego po likwidacji jednolitych studiów magisterskich. Szczególną uwagę poświęcono nieprawidłowościom i akademickim patologiom w procesie kształcenia nauczycieli.
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Abstract

This paper presents a synthesis of research in the field of social activity in development of urban public spaces. Interest in social participation in which many groups sees a remedy to the problems of the city - including spatial chaos - has many causes. One of them is the lack of trust in the social side to the profession of architecture. The article indicates the possible cause of this state for which it was flawed legislation and the planning system, which in practice is not conducive to the formation of order, harmony and beauty, but facilitate the implementation of the narrow groups of interests, bringing the rank of designer as creator of the role of the investor's decision executor.
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Abstract

This paper presents the findings of a study of gas emissivity and the volumetric gas flow rate from a patented modified cellulose mix used in production of disposable sand casting moulds. The modified cellulose mix with such additives as expanded perlite, expanded vermiculite and microspheres was used as the study material. The results for gas emissivity and the gas flow rate for the modified cellulose mix were compared with the gas emissivity of the commercial material used in gating systems in disposable sand casting moulds. The results have shown that the modified cellulose mix is characterized by a lower gas emissivity by as much as 50% and lower gas flow rate per unit mass during the process of thermal degradation at the temperature of 900°C, compared to the commercial mix. It was also noted that the amount of microspheres considerably affected the amount of gas produced.
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Abstract

The level of sales of a given good depends largely on the distribution network. An analysis of the distribution network allows companies to optimize business activity, which improves the efficiency and profitability of a company’s sales with an immediate effect on profit growth. The so-called spatial analysis is highly useful in this regard. The paper presents an analysis of the network of authorized dealers of the Polish Mining Group for the Opolskie Province. The analysis was done using GIS (SIP) tools. The purpose of the analysis was to present tools that could be used to verify an existing distribution network, to optimize it, or to create a new sales outlet. The prresented tools belong to GIS operations used to process data stored in Spatial Information System resources. These are so-called geoprocessing tools. The article contains several spatial analyses, which results in choosing the optimum location of the distribution point in terms of the defined criteria. The used tools include a spatial intersection and sum. Geocoding and the so-called cartodiagram were also used. The presented analysis can be performed for both the network of authorized retailers within a region, a city or an entire country. The presented tools provide the opportunity to specify the target consumers, areas where they are located and areas of potential consumer concentration. This allows the points of sale in areas with a high probability of finding new customers to be located, which enables the optimal location to be chosen, for example, in terms of access to roads, rail transport, locations of the right area and neighborhood. Spatial analysis tools will also enable the coal company to verify its already existing distribution network.
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Abstract

In the paper the parametric optimization problem for a linear system with two delays and a PD-controller is presented. In the parametric optimization problem the quadratic performance index is considered. The value of the quadratic index of quality is calculated due to the Lyapunov functional and is equal to the value of that functional for the initial function of the neutral system with two delays. The Lyapunov functional is determined by means of the Lyapunov matrix.
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Abstract

The article addresses the issues falling within the scope of the economic analysis of a detached building’s heating system with a direct evaporation ground source heat pump installation. The paper was elaborated based on the data made available by the investment’s contractor and the investor. The paper provides data on the investment expenditures and utility cost, calculations of the installation payback, internal return rate and the current net value.
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Abstract

The paper presents the operation of two neuro-fuzzy systems of an adaptive type, intended for solving problems of the approximation of multi-variable functions in the domain of real numbers. Neuro-fuzzy systems being a combination of the methodology of artificial neural networks and fuzzy sets operate on the basis of a set of fuzzy rules “if-then”, generated by means of the self-organization of data grouping and the estimation of relations between fuzzy experiment results. The article includes a description of neuro-fuzzy systems by Takaga-Sugeno-Kang (TSK) and Wang-Mendel (WM), and in order to complement the problem in question, a hierarchical structural self-organizing method of teaching a fuzzy network. A multi-layer structure of the systems is a structure analogous to the structure of “classic” neural networks. In its final part the article presents selected areas of application of neuro-fuzzy systems in the field of geodesy and surveying engineering. Numerical examples showing how the systems work concerned: the approximation of functions of several variables to be used as algorithms in the Geographic Information Systems (the approximation of a terrain model), the transformation of coordinates, and the prediction of a time series. The accuracy characteristics of the results obtained have been taken into consideration.
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Abstract

Polish cadastral system consists of two registers: cadastre and land register. The cadastre register data on cadastral objects (land, buildings and premises) in particular lo- cation (in a two-dimensional coordinate system) and their attributes as well as data about the owners. The land register contains data concerned ownerships and other rights to the property. Registration of a land parcel without spatial objects located on the surface is not problematic. Registration of buildings and premises in typical cases is not a problem either. The situation becomes more complicated in cases of multiple use of space above the parcel and with more complex construction of the buildings. The paper presents rules concerning the registration of various untypical 3D objects located within the city of Warsaw. The analysis of the data concerning those objects registered in the cadastre and land register is presented in the paper. And this is the next part of the author’s detailed research. The aim of this paper is to answer the question if we really need 3D cadastre in Poland.
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Abstract

The paper presents kinematic characteristics of the double 4-link coupler system, used in actual powertrain of low-floor trams (NGT6-Kr). The spatial kinematic model of the couplings was formulated assuming ideal joints and rigid members. The constraints equations of the mechanism were solved iteratively and differentiated to obtain the Jacobian matrix. The mobility and singularity analysis of the coupler mechanism was performed on the basis of the Jacobian matrix. Kinematic characteristics of the single and double coupler system were analyzed for gross angular and linear axle displacements (misalignments), taking the advantage of the fully nonlinear model. The coupling system was evaluated based on criteria describing homokinetics, balancing and clearance demands, and angular displacements in the joints. These criteria were determined for different design parameters like: coupler proportions, platform shift and angle, middle shaft length.
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Abstract

Recently, the rapid advancement of the IT industry has resulted in significant changes in audio-system configurations; particularly, the audio over internet protocol (AoIP) network-based audio-transmission technology has received favourable evaluations in this field. Applying the AoIP in a certain section of the multiple-cable zone is advantageous because the installation cost is lower than that for the existing systems, and the original sound is transmitted without any distortion. The existing AoIP-based technology, however, cannot control the audio-signal characteristics of every device and can only transmit multiple audio signals through a network. In this paper, the proposed Audio Network & Control Hierarchy Over peer-to-peer (Anchor) system enables all audio equipment to send and receive signals via a data network, and the receiving device can mix the signals of different IPs. Accordingly, it was possible to improve the system-application flexibility by simplifying the audio-system configuration. The research results confirmed that the received audio signals from different IPs were received, mixed, and output without errors. It is expected that Anchor will become a standard for audio-network protocols.
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Abstract

The article features a systemic approach to digitalization in mining, covering the production process, supervision and management. Business continuity management of a critical infrastructure was characterized with respect to an industrial facility, i.e. a mine. The “SILESIA” Integrated Security System was described. This solution, offered by CNP EMAG, is an example of a systemic approach successfully implemented in industry. The article includes information about the development of technological hardware solutions as well as software which is able to assess the solutions developed in the SecLab Information Security Technology Development Laboratory in the EMAG Institute.
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Abstract

The powerful tool for defect analysis is an expert system. It is a computer programme based on the knowledge of experts for solving the quality of castings. We present the expert system developed in the VSB-Technical University of Ostrava called ‘ESWOD’. The ESWOD programme consists of three separate modules: identification, diagnosis / causes and prevention / remedy. The identification of casting defects in the actual form of the system is based on their visual aspect.
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