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Number of results: 164
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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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Authors and Affiliations

Adam Ruciński
Artur Rusowicz
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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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Authors and Affiliations

Jingsong Li
Andreas Reiffs
Uwe Parchatka
Horst Fischer
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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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Authors and Affiliations

Bożena Smagowska
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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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Authors and Affiliations

Bogusław Krasnowolski
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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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Authors and Affiliations

Karol Tucki
Michał Sikora
Magdalena Karlikowska
Wojciech Będkowski
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Abstract

The effect of total energy consumption and electric energy consumption on cumulated noxiousness index (SWU) value of coke production process, steel rolled goods and PVC windows profiles is presented in the paper. Using the sequential analysis it was proved that in SWU of the prediction process, from the stage of law materials to the final product, the onerousness connected with energy consumption amounts from 70% up to 81%, whereas that connected with electric energy directly or indirectly consumed - from 60% up to 77%.
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Authors and Affiliations

Agata Malina
Jan Konieczyński
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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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Authors and Affiliations

Ramón Peral-Orts
Emilio Velasco-Sánchez
Nuria Campillo-Davó
Héctor Campello-Vicente
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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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Authors and Affiliations

Wiesław Kaszowski
Tomasz Ściężor
Marek Kubala
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Abstract

The purpose of the article is to present perspectives for the development of offshore wind farms in the leading, in this respect, country in the EU and in the world – Great Britain. Wind power plays a remarkable role in the process of ensuring energy security for Europe since in 2016 the produced wind energy met 10.4% of the European electricity demand while in 2017 it was already around 11.6%. The article analyses the capacity of wind farms, support systems offered by this country and the criteria related to the location of offshore wind farms. The research has been based on the analysis of legal acts, regulations, literature on the subject, information from websites. The article shows that in recent years, the production of energy at sea has been developing very rapidly, and the leading, in this matter, British offshore energy sector is character-ised by strong governmental support.

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Authors and Affiliations

Leszek Dawid
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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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Authors and Affiliations

Barbara Ostafin
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Abstract

The Author presents several methodological aspects referring to photographs as historical sources. In this article it is viewed as an iconographic source. The problem of photographs as iconographic sources is discussed in the context of historical semantics and theory of historical presence.
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Authors and Affiliations

Agata Barzycka
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Abstract

The constant increase in the popularity of renewable energy systems allows residential building users to apply solutions leading to the diversification of the energy supply. The use of RES systems in residential buildings not only contributes to a higher level of environmental care, but also significantly and measurably improves the energy efficiency of the facility. Using hybrid systems allows the supply to be reduced or eliminated from conventional energy sources. The article presents common layouts of renewable energy systems, which are successfully used in residential buildings. It also shows the impact of such systems on the amount of savings achieved in the use of energy from external or conventional sources. In residential buildings, the possibility of energy generation in the form of electricity and heat is dependent on many factors that determine the type and size of the systems used to obtain energy from renewable sources. We should assume the further and continuous development of RES, which will increase the share of electricity and heat produced in households. Technological development, decreasing prices of equipment and components used for the installation of green electricity generation systems will be a conducive factor for increasing the popularity of RES systems, not only for residential buildings but also for other types of buildings. The article also points out the economic aspect of the RES systems application. It presents the positive impact of RES installations on the environment and estimates the average time of financial reimbursement. The economic analysis concerns individual systems of renewable energy systems used in residential buildings.

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Authors and Affiliations

Sławomir Sowa
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Abstract

The aim of this article is to present selected methodological threads of the discussion on the status of historical sources which took place in Polish post‑war historiography. In the article, I present the concepts of the historical source formulated in 1957–1989, mainly by Gerard Labuda and Jerzy Topolski. Further in the text, I will present the discussion about Topolski’s concepts and characterize the peculiarities of contemporary history as regards historical sources. In the light of the presented classification of sources, I will reflect on the status of the documents created by the apparatus of repression of the Polish People’s Republic.
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Authors and Affiliations

Krzysztof Brzechczyn
1 2
ORCID: ORCID

  1. Adam Mickiewicz University, Poznań
  2. Historical Research Office, Institute of National Remembrance, Poznań Branch
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Abstract

The Author disusses Ernst Bernheim’s idea of historical source as it was presented in his “Lehrbuch der historischen Methode und der Geschichtsphilosophie”.
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Authors and Affiliations

Aleksandra Kuligowska
ORCID: ORCID
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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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Authors and Affiliations

Sławomir Sowa
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Abstract

Experts from Poland are involved in designing and building the world’s strongest pulsed neutron source for investigating the properties of condensed matter.
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Authors and Affiliations

Dariusz Bocian
Wojciech Zając
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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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Authors and Affiliations

Tadeusz Srogosz
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Abstract

This article is devoted to current practices concerning the application of general principles of law in the light of their function in the international legal system. As a means of the application and interpretation of both treaty and customary law, general principles of law perform a crucial function in the system of international law, which is understood as set of interrelated rules and principles – norms. The role played by general principles of law in the international legal order has been discussed by academia for years now. Initially they were used to ensure the completeness of the system of international law. However, at the current stage of development of international law, when many of them have been codified, they are usually invoked by international courts for the interpretation of treaties and customary law and/or the determination of their scope. This means that despite their ongoing codification they do not lose their character as general principles and are still applied by international courts in the process of judicial argumentation and the interpretation of other norms to which they are pertinent. References by international courts to general principles of law perform the allimportant function of maintaining the coherence of the international legal order, which is faced with the twin challenges of fragmentation and the proliferation of international courts.

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Authors and Affiliations

Izabela Skomerska-Muchowska
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Abstract

This study presents an attempt to design geographical visualisation tools that allow to tackle the immensity of spatial data provided by Volunteered Geographic Information (VGI), both in terms of temporal and spatial aspects. In accordance with the assumptions made at the conceptual stage, the final action was the implementation of the window entitled ‘Geovisualisation of the Panoramio.com Activities in District of Poznań 2011’ into the web browser. The concept has been based on a division of the geovisualisation window into three panels, of which the most important - in order to capture spatial variability - have statistical maps at the general level (dot map and choropleth map), while at the detailed level - a dot map on a topographic reference map or tourist map. For two ranges, temporal variability is presented by graphs, while a review of attributes of individual activities of the social website in question is set forward in the table panel. The element that visually interlinks all of the panels is the emphasised individual activity.
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Authors and Affiliations

Beata Medyńska-Gulij
Miłosz Myszczuk
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Abstract

The paper presents a method of identifying distant emission sources of fine particulate matter PM2.5 affecting significantly PM2.5 concentrations at a given location. The method involves spatial analysis of aggregate information about PM2.5 concentrations measured at the location and air masses backward trajectories calculated by HYSPLIT model. The method was examined for three locations of PM2.5 measurement stations (Diabla Góra, Gdańsk, and Katowice) which represented different environmental conditions. The backward trajectories were calculated starting from different heights (30, 50, 100 and 150 m a. g. l.). All points of a single backward trajectory were assigned to the PM2.5 concentration corresponding to the date and the site of the beginning of trajectory calculation. Daily average concentrations of PM2.5 were used, and in the case of Gdańsk also hourly ones. It enabled to assess the effectiveness of the presented method using daily averages if hourly ones were not available. Locations of distant sources of fine particulate matter emission were determined by assigning to each grid node a mean value of PM2.5 concentrations associated with the trajectories points located within the so-called search ellipse. Nearby sources of fine particulate matter emission were eliminated by filtering the trajectories points located close to each other (so-called duplicates). The analyses covered the period of January-March 2010. The results indicated the different origin of air masses in the northern and southern Poland. In Diabla Góra and Gdańsk the distant sources of fine particulate matter emission are identified in Belarus and Russia. In Katowice the impact of the Belarusian PM2.5 emission sources was also noted but as the most important fine particulate matter emission sources were considered those located in the area of Romania, Hungary, Slovakia and Ukraine.

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Authors and Affiliations

Jolanta Godłowska
Monika J. Hajto
A. Monika Tomaszewska
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Abstract

The optimal energy management (OEM) in a stand-alone microgrid (SMG) is a challenging job because of uncertain and intermittent behavior of clean energy sources (CESs) such as a photovoltaic (PV), wind turbine (WT). This paper presents the effective role of battery energy storage (BES) in optimal scheduling of generation sources to fulfill the load demand in an SMG under the intermittency of theWT and PV power. The OEM is performed by minimizing the operational cost of the SMG for the chosen moderate weather profile using an artificial bee colony algorithm (ABC) in four different cases, i.e. without the BES and with the BES having a various level of initial capacity. The results show the efficient role of the BES in keeping the reliability of the SMG with the reduction in carbon-emissions and uncertainty of the CES power. Also, prove that the ABC provides better cost values compared to particle swarm optimization (PSO) and a genetic algorithm (GA). Further, the robustness of system reliability using the BES is tested for the mean data of the considered weather profile.

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Authors and Affiliations

Navin Kumar Paliwal
Asheesh Kumar Singh
Navneet Kumar Singh
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Abstract

Water is an essential commodity which affects life and livelihoods in the universe. This study examined perceived ef-fect of water scarcity on livelihoods in Iwoye-Ketu, Ogun State. Random sampling was used to select 80 rural households and water samples for the study. Data collected were analysed using descriptive, inferential and laboratory analyses. Find-ings showed that the mean age of respondents was 38 years with an average household size of four persons. The major sources of water were boreholes (97.5%) and rainwater (90.0%), the average trekking time to the water source was 24 minutes and the households requires an average of 162 litres of water per day. Water analysis’ result showed that the water has pH (6.87), total dissolved solids (0.175 mg∙dm–3), temperature (29.9°C) and turbidity (0.6 FTU). The major causes of water scarcity include insufficient rainfall (97.5%), increased sunlight intensity (97.5%), pollution of water sources (95.0%)and increased population (93.8%). About 60% of them perceived water scarcity to have a negative effect on their liveli-hoods. Correlation analysis shows that there is a significant relationship between usage of water (r = 0.370, p < 0.01) and perceived effect of water scarcity. It was concluded that water available for household use is not sufficient, although it is safe but contain some elements which are not of World Health Organization standard for good potable water. It is recom-mended that the community should build a hub for water collection and distribution close to the village centre and the gov-ernment should provide water infrastructures to increase the supply of potable water.

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Authors and Affiliations

Adetayo K. Aromolaran
Ibiyinka O. Ademiluyi
Abiodun E. Sotola
Felicia I. Wole-Alo
Oluwadamilola A. Aromiwura
Olubukola E. Ogunsuyi

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