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Number of results: 38
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Abstract

Scientific research on urban and rural layouts should form an important element of studying the history of cities and villages, something which requires a coordination of multiple disciplines. One must make use of source material, yet be able to tell the difference between the source and its interpretation or critique. The importance of source material varies depending on the period and area in question. When investigating Early Medieval Poland, for instance, one should focus on geological and archeological sources. The later periods show a much larger wealth of written sources and accounts. Beginning from the period of founding cities based on German laws in the thirteenth and fourteenth centuries, city plans and cartographic sources are of increasing value, as they make it possible to perform modular analyses. The role of iconographic source material increases during from the modern period all the way to our times. The method of research here is the correlation of the information gained from these sources onto modern urban layouts. We can interpret the subsequent phases of development based on this. Using modular analysis we can then identify the historical and agricultural conditions of the time. This research should be conducted by a team of academics from various different fields. An example of such a cooperation is the Atlas Miast Polskich (The Atlas of Polish Cities).
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Abstract

The paper presents an analysis of the influence of the energy generated from renewable sources on an improvement in the energy efficiency of public utility building and households. It also presents the current state of the technologies for the production of electricity from renewable sources, as well as their share in the national power supply system. The conducted analysis concerns both micro, as well as large systems generating electricity. Systems generating power from renewable sources are gaining in popularity. With an increasing awareness in the society of the beneficial influence that renewable power generating systems have on the environment, as well as the support in form of various programs offering subsidies for the construction of new systems, power generation from renewable sources is becoming increasingly popular and common. Although the renewable energy systems are still not widely considered to be a profitable solution, systems using renewable sources of energy are positively perceived and treated as a new trend in the construction of multi or single-family residential buildings. The increasing share of the renewable energy in the national power supply system significantly reduces the demand for energy produced from conventional sources. This obviously translates into a reduced consumption of primary energy, for example, fossil fuels, and, in turn, leads to the reduced exploitation of natural resources, thus contributing to the protection of the natural environment. A reduced consumption of fossil fuels also means a significant reduction in environmental pollution during their processing into electricity or heat. Actions aiming at improving energy efficiency and reducing final energy consumption are being undertaken by many countries all over the world, and by the European Union. In 2012, the European Parliament and the Council issued Directive 2012/27/EU obliging the Member States to initiate actions aiming at a reduction in the consumption of final energy by 1.5% a year. The paper presents the current status of generation of energy from renewable sources during the last 13 years. The ways for using energy from the renewable sources to improve the energy efficiency of facilities were also discussed.
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Abstract

The article will consider the possibility of using sources in modernising the biological study of existence in history on the basis of selected trends of “modern historiography”. The problem of sources is considered in the context of the use of anthropology of knowledge, historical anthropology, microhistory, and chaos theory in historical-medical research. In this process, I see an opportunity to look for new research spaces and, therefore, ask new questions to source messages or to search for new ones. Therefore, it is important not to forget about the need to base the narrative on the source while introducing methodological innovations.
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Abstract

Ambient concentrations of CO, as well as NOx and O3, were measured as a part of the PARADE campaign conducted at the Taunus Observatory on the summit of the Kleiner Feldberg between the 8th of August and 9th of September 2011. These measurements were made in an effort to provide insight into the characteristics of the effects of both biogenic and anthropogenic emissions on atmospheric chemistry in the rural south-western German environment. The overall average CO concentration was found to be 100.3±18.1 ppbv (within the range of 71 to 180 ppbv), determined from 10-min averages during the summer season. The background CO concentration was estimated to be ~90 ppbv. CO and NOx showed bimodal diurnal variations with peaks in the late morning (10:00-12:00 UTC) and in the late afternoon (17:00-20:00 UTC). Strong correlations between CO and NOx indicated that vehicular emission was the major contributor to the notable CO plumes observed at the sampling site. Both local meteorology and backward trajectory analyses suggest that CO plumes were associated with anthropogenically polluted air masses transferred by an advection to the site from densely populated city sites. Furthermore, a good linear correlation of R2 = 0.54 between CO and O3 (∆O3/∆CO=0.560±0.016 ppbv/ppbv) was observed, in good agreement with previous observations
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Abstract

This paper provides some information about thermoelectric technology. Some new materials with improved figures of merit are presented. These materials in Peltier modules make it possible to generate electric current thanks to a temperature difference. The paper indicates possible applications of thermoelectric modules as interesting tools for using various waste heat sources. Some zero-dimensional equations describing the conditions of electric power generation are given. Also, operating parameters of Peltier modules, such as voltage and electric current, are analyzed. The paper shows chosen characteristics of power generation parameters. Then, an experimental stand for ongoing research and experimental measurements are described. The authors consider the resistance of a receiver placed in the electric circuit with thermoelectric elements. Finally, both the analysis of experimental results and conclusions drawn from theoretical findings are presented. Voltage generation of about 1.5 to 2.5 V for the temperature difference from 65 to 85 K was observed when a bismuth telluride thermoelectric couple (traditionally used in cooling technology) was used.
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Abstract

The use of ultrasonic energy has created versatile possibilities of their applications in many areas of life, especially in hydro location and underwater telecommunications, industry and medicine. The consequence of a widespread use of high intensity ultrasonics in technology is the increased number of people who are exposed to such ultrasonic noise. Therefore it is important to determine the types of machines and other devices that are responsible for the emission of ultrasonic noise (10-40 kHz of central frequencies of one-third octave bands) as harmful and annoying hazard in the work environment. This paper presents ultrasonic noise sources frequently used in industry and preventive measures reducing the exposure to ultrasonic noise. Two types of ultrasonic noise sources have been distinguished: machines and other devices used to carry out or improve production processes, the so-called technological sources and sources in which ultrasonic noise exists as a non-intentional result of operation of many machines and systems, the so-called non-technological sources of ultrasonic noise. The emission of SPL has been determined for each groups of devices based on own measurement results.
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Abstract

The energy efficiency of photovoltaic modules is one of the most important aspects in energetic and economic aspects of the project related to system installations. The efficiency of modules and the electricity produced by photovoltaic conversion in solar modules is affected by many factors, both internal, related to the module structure itself and its technical and external factors related to the energy infrastructure, which includes: cabling, inverters, climate conditions prevailing at the micro-installation location and the orientation and angle of inclination of the solar modules. The installation of photovoltaic modules should be preceded by an energy efficiency analysis, which will help to indicate the optimal solution adapted to the given conditions. The article presents a comparative analysis of the amount of energy produced under real and simulated conditions. Analyzes were made on the basis of research carried out in the Wind and Solar Energy Laboratory located at the AGH University of Science and Technology, data from solar irradiation data-bases and computer software for estimating energy resources. The study examined the correlation of the solar irradiation on the modules and the amount of electricity generated in the photovoltaic module. The electricity produced by the module was compared under real conditions and simulated based on two sources of data. The comparison and analysis of the amount of energy of the module were also made, taking simulated different angles of the module’s inclination into account.
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Abstract

A novel method of active noise control using adaptive radiation sound sources is investigated. A finite element model of a modal enclosed sound field is excited harmonically, representing a noise field in the low-frequency range. The control sources are comprised of elementary dipole sources for which the driving signals are adjusted by an optimization method. Two set-up cases of the proposed compound sources are investigated. The coupling of the control sources with the modal sound field is discussed. The simulated performance of the proposed method is compared with that of a system with distributed simple sources and the results show the effectiveness of the sources with adaptive radiation for active noise control in small enclosures.
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Abstract

The large variability and unpredictability of energy production from photovoltaic power microinstallations results from the dependence on the current weather conditions. These conditions depend on a number of factors and are variable over the time. Despite this specificity, photovoltaic micro-installations are becoming more and more popular in the world and in Poland. This is mainly due to the fact that the generation of energy from renewable sources has numerous advantages, the energy is free, renewable in time and ecological, and its production on its own gives partial independence from energy supplies from the power grid. In addition, the observed significant prices decrease of solar modules has further accelerated the development of the use of this energy source. Concern for this method of energy production among households has increased significantly in Poland after introducing the prosumer in the legal framework and the use of administrative and financial support. The implemented prosumer mechanisms allowed, for example, the net balancing of the energy consumed and produced by the micro-installation through storage in the power grid. The article describes the problem of balancing sources using solar energy, based on micro-installation used in the household (the so-called prosumer installation). The conducted analyses compared the load profile of a typical household and the energy generation profile from a photovoltaic installation, determining the real balancing formation level of such a system.
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Abstract

The Polish energy sector is, to a large extent, based on fossil fuels used in conventional energy, which is not entirely consistent with the current energy policy of the European Union. Therefore, it is necessary to increase the use of renewable energy sources that guarantee the preservation of the value of the natural environment in rural areas. It should be emphasized that in addition to the economic effect, the environmental effect is very important, understood as the impact of renewable energy on the natural environment and the quality of life of rural residents. The intensive development of RES raises a lot of controversy among politicians, as well as among rural residents, who are also associated with the myths regarding renewable energy as harmful to the natural environment. Rural development should be connected with the socio-economic situation, and even more so with the socio-cultural situation of its inhabitants, because it assumes that the development of rural areas in Poland is associated not only with agriculture, but also with historical and natural values and their durability. The aim of this work is to determine the attitudes of the inhabitants of rural areas of the Podkarpackie Province on the impact of renewable energy sources on the natural environment. The work assumes that the durability of rural areas is largely connected with the ability to preserve their natural values, as well as ensuring a satisfactory quality of life for residents. The basic source of data was surveys carried out in 2017 among 282 inhabitants of the Podkarpackie Province .
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Abstract

The implementation of micro scale combined heat and power systems is one of the ways to improve the energy security of consumers. In fact, there are many available large and medium scale cogeneration units, which operate according to the Rankine Cycle. Due to European Union demands in the field of using renewable energy sources and increasing energy efficiency result in the importance of additionally developing systems dedicated for use in residential buildings, farms, schools and other facilities. This paper shows the concept of introducing thermoelectric generators into typical wood stoves: steel plate wood stoves and accumulative wood stoves. Electricity generated in thermoelectric generators (there were studies on both three market available units and a prototypical unit developed by the authors) may be firstly consumed by the system (to power controller, actuators, fans, pumps, etc.). Additional power (if available) may be stored in batteries and then used to power home appliances (light, small electronics and others). It should be noted that commercially available thermoelectric generators are not matched for domestic heating devices – the main problems are connected with an insufficient heat flux transmitted from the stove to the hot side of the generator (caused e.g. by the non -homogeneous temperature distribution of the surface and bad contact between the stove and the generator) and inefficient cooling. To ensure the high efficiency of micro cogeneration systems, developing a dedicated construction both of the generator and the heat source is necessary.
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Abstract

The aim of the text is to describe some use of literary studies for the studies of history. First of all the recent evolution of the literary studies is outlined, with special stress on expansion of the notion of the subject. It is not any more limited to a human actor, but can be applied to an animal or even an inanimate object. The notion of discursive practice is introduced as a one of the principal key notions of contemporary literary studies. Then few application of literary analysis of discourse for history is enumerated, such as: expanding the scope of historical sources so as to include literary works and other piece of art; critical analysis of historiographical discourse as a text; a new approach to traditional historical sources consisting in treating them as autonomic texts of culture deserving interpretative activity in themselves.
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Abstract

Hybrid Renewable Energy Systems connected to the traditional power suppliers are an interesting technological solution in the field of energy engineering and the integration of renewable systems with other energy systems can significantly increase in energy reliability. In this paper, an analysis and optimization of the hybrid energy system, which uses photovoltaic modules and wind turbines components connected to the grid, is presented. The system components are optimized using two objectives criteria: economic and environmental. The optimization has been performed based on the experimental data acquired for the whole year. Results showed the optimal configuration for the hybrid system based on economical objective, that presents the best compromise between the number of components and total efficiency. This achieved the lowest cost of energy but with relatively high CO2 emissions, while environmental objective results with lower CO2 emissions and higher cost of energy and presents the best compromise between the number of components and system net present cost. It has been shown that a hybrid system can be optimized in such a way that CO2 emission is maximally reduced and – separately – in terms of reducing the cost. However, the study shows that these two criteria cannot be optimized at the same time. Reducing the system cost increase CO2 emission and enhancing ecological effect makes the system cost larger. However, depends on strategies, a balance between different optimization criteria can be found. Regardless of the strategy used economic criteria – which also indirect takes environmental aspects as a cost of penalties – should be considered as a major criterion of optimization while the other objectives including environmental objectives are less important.
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Abstract

The article discusses the importance of small hydro power plants in the Polish power system and defines the legal conditions for the operation of small hydro power plants. The phenomena occurring in the hydrological system of small hydro power plants and their impact on the natural environment were analyzed. An analysis of phenomena occurring in the hydrological system and the activity of small hydro power plants that are operating on the Radunia River helped us identify relations between different types of power plants working in cascades and possibilities of power generation control in period of several days. The above-mentioned analysis has been used in the development of a mathematical model of a hydroelectric plant and cascades of hydroelectric plants. The numerical simulations carried out concerned both the self-operating power plant and a cascade of two identical objects of this type. There is a possibility for small hydro power plant to run as a base load power plant and during periods of high demand as well (peak demand or unexpected loss of generation in the power system). A single hydroelectric power plant can deal with varying peak load demands while adding a second stage increase those abilities. A cascade of reservoir hydropower plants has a much greater ability to store energy and give it back in time. In addition, the existence of a second power plant equipped with a surge reservoir allows for a significant reduction in the amplitude of flows in the river below the cascade, which will reduce the negative impact of the cascade on the environment.
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Abstract

When the distribution of water quality samples is roughly balanced, the Bayesian criterion model of water-inrush source generally can obtain relatively accurate results of water-inrush source identification. However, it is often difficult to achieve desired classification results when training samples are imbalanced. Sample imbalance is common in the source identification of mine water-inrush. Therefore, we propose a three-dimensional (3D) spatial resampling method based on rare water quality samples, which achieves the balance of water quality samples. Based on the virtual water sample points distributed by the 3D grid, the method uses the 3D Inverse Distance Weighting (IDW) method to interpolate the groundwater ion concentration of the virtual water samples to achieve oversampling of rare water samples. Case study in Gubei Coal Mine shows that the method improves overall discriminant accuracy of the Bayesian criterion model by 5.26%, from 85.26% to 90.69%. In particular, the discriminative precision of the rare class is improved from 0% to 83.33%, which indicates that the method can improve the discriminant accuracy of the rare class to large extent. In addition, this method increases the Kappa coefficient of the model by 19.92%, from 52.26% to 72.19%, increasing the degree of consistency from “general” to “significant”. Our research is of significance to enriching and improving the theory of prevention and treatment of mine water damage.
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Abstract

Pollution, climate change and energy security are significant problems. Climate-disrupting fossil fuels are being replaced by clean and non-depletable sources of energy. It requires major changes to energy infrastructures and strong support for promotion of the use of energy from renewable sources. Renewable energy is emerging as a driver of inclusive economic growth and reinforcing energy security. Public entities have to promote renewable energy development by implementing cost-effective national support schemes. By acting at national-level, several barriers to public and private investments could be tackled, addressing the lack of coordination between various authorising bodies at national level and stimulatng the administrative capacity to implement energy projects. It should be effective in promoting transparency for investors and others economic operators. In Poland there is a lack of regulatory policies creating incentives for decentralised energy. Market-based support schemes are still needed for small-scale self-consumption system. Currently operating solutions have been shown in the contrast of the ones applied abroad. The development of clean energy technologies depends on many factors. The author identified few most important ones, mainly financial, regulatory issues, social, environmental and characterized them in this work. The article presents the recommendations of regulatory framework and some proposals for energy cluster based policy’s tools, the introduction of which would significantly facilitate the wider renewable energy uses in Poland.
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Abstract

Using renewable energy sources for electricity production is based on the processing of primary energy occurring in the form of sun, wind etc., into electrical energy. Economic viability using those sources in small power plants strongly depends on the support system, based mainly on financial instruments. Micro-installations, by using special instruments dedicated to the prosumer market may become more and more interesting not only in terms of environmental energy, but also financial independence. In the paper, the term hybrid power plant is understood to mean a production unit generating electricity or electricity and heat in the process of energy production, in which two or more renewable energy sources or energy sources other than renewable sources are used. The combination of the two energy sources is to their mutual complementarity, to ensure the continuity of the electricity supply. The ideal situation would be if both sources of energy included in the hybrid power plant continuously covered the total demand for energy consumers. Unfortunately, due to the short-term and long-term variability of weather conditions, such a balance is unattainable. The paper assesses the possibility of balancing the hybrid power plant in daily and monthly periods. Basic types of power plants and hybrid components and system support micro-installations were characterized. The support system is based particularly on a system of feed-in tariffs and the possibility of obtaining a preferential loan with a subsidy (redemption of part of the loan size). Then, an analysis of energy and economic efficiency for a standard set of hybrid micro-installations consisting of a wind turbine and photovoltaic panels with a total power of 5 kW, were presented. Fourteen variants of financing, economic efficiency compared with the use of the method of the simple payback period were assumed.
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Abstract

This paper presents mathematical models enabling the calculation of the distribution and patterns of methane inflow to the air stream in a longwall seam being exploited and spoil on a longwall conveyor, taking into account the variability of shearer and conveyor operation and simulation results of the mining team using the Ventgraph-Plus software. In the research, an experiment was employed to observe changes in air parameters, in particular air velocity and methane concentration in the Cw-4 longwall area in seam 364/2 at KWK Budryk, during different phases of shearer operation in the area of the mining wall in methane hazard conditions. Presented is the method of data recording during the experiment which included records from the mine’s system for automatic gasometry, records from a wireless system of eight methane sensors installed in the end part of the longwall and additionally from nine methane anemometers located across the longwall on a grid. Synchronous data records obtained from these three independent sources were compared against the recording the operating condition of the shearer and haulage machines at the longwall in various phases of their operation (cleaning, cutting). The results of the multipoint system measurements made it possible to determine the volume of air and methane flow across the longwall working, and, consequently, to calculate the correction coefficients for determining the volume of air and methane from measurements of local air velocity and methane concentration. An attempt was made to determine the methane inflow from a unit of the longwall body area and the unit of spoil length on conveyors depending on the mining rate. The Cw-4 longwall ventilation was simulated using the data measured and calculated from measurements and the simulation results were discussed.
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Abstract

The article presents selected issues from the Polish Energy Policy draft until 2040. From many issues, the authors chose the ones they considered the most revolutionary. Firstly, the National Power System should be restructured to meet the challenges of a changing environment, be adapted to the growing demand for electricity, and at the same time have the least impact on the natural environment. These goals can be achieved through reforms to reduce the importance of coal in the energy mix and the development of renewable energy sources, especially offshore wind energy. The next tasks are the development of electromobility, enabling the reduction of pollution caused by transport, and, in the longer term, after 2030, the development of nuclear energy in place of the withdrawn coal power.
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Abstract

The article describes selected issues falling within the scope of the technical analysis of a detached building’s heating system with a direct evaporation ground source heat pump installation. This paper covers the characteristics of modernized facility as well as calculations to determine the heat demand. What is more, the article describes the manner in which heat pumps shall be selected, its installation components as well as the receiving installation.
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Abstract

The great 13th century scholar Yāqūt al-Hamawī, compiled his well-known geographical dictionary – Mucğam al-Buldān – using an incredibly vast corpus of sources that allowed him to describe the lands lying beyond the realm of Islam. The aim of this paper is to identify the sources he used to describe issues dealing with the Slavs or those peoples and areas thought by Arab writers to belong to or be connected with the Slavs. The results shed some light on the state of knowledge of this area among 13th century inhabitants of the caliphate. At the same time, the author’s analysis of the methods employed to compose the material on the Slavs that appears in the Dictionary helped determine the aim and the role of this work in the caliphate.
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Abstract

The noise of motor vehicles is one of the most important problems as regards to pollution on main roads. However, this unpleasant characteristic could be used to determine vehicle speed by external observers. Building on this idea, the present study investigates the capabilities of a microphone array system to identify the position and velocity of a vehicle travelling on a previously established route. Such linear microphone array has been formed by a reduced number of microphones working at medium frequencies as compared to industrial microphone arrays built for location purposes, and operates with a processing algorithm that ultimately identifies the noise source location and reduces the error in velocity estimation
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Abstract

The existence of extensive records for the impact of night sky brightness on the animals’ behavior in their natural environment shows the need to investigate the level of artificially induced night sky glow (light pollution) in the protected areas. The results of multi-night sky brightness measurements carried out at the selected sites in Polish mountain areas under various atmospheric conditions are presented. Conducted measurements show a strong impact of the artificial sky glow on the night sky brightness, which is the essence of light pollution. The influence of both distant urban centers, as well as local tourist resorts on the size of studied phenomenon in the mountain areas, which causes both ecological and touristic degradation of these areas was stated. In a few studied areas the level of night sky brightness greatly exceeds the natural one and is comparable to such levels measured inside the cities. It was found that only the southern part of the Polish Carpathians can be considered an area free of light pollution.
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