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Number of results: 108
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Abstract

The Lower Devonian ‘Placoderm Sandstone’ in the Holy Cross Mountains (HCM) is filled with abundant impressions

of disarticulated vertebrate remains. The only acanthodian macroremains named to date are fin spines

of Machaeracanthus polonicus Gürich. Fin spine impressions in slabs from the Winna Formation (Emsian) at

Podłazie Hill (near Daleszyce) in the southern HCM, and also the Barcza Formation (?Lochkovian) at Barcza

Quarry, Miedziana Góra Conglomerate (?Lochkovian), Gruchawka, and Zagórze Formation (middle–upper

Emsian) at Bukowa Mountain in the northern HCM, reposited in the University of Warsaw, Polish Geological

Institute-National Research Institute, Warsaw, and Natural History Museum, London collections, have been cast

and studied in order to better document this poorly known taxon. As noted in other Machaeracanthus species,

we have found that M. polonicus has two different morphotypes of spines, which abut lengthwise to form a pair

of spines. Our investigations show that the fin spine assemblage includes Onchus overathensis as well as M.

polonicus, and probably another undetermined acanthodian. The affinities of O. overathensis are reassessed.

It is here considered to be a diplacanthiform, and reassigned to the genus Striacanthus, as S. overathensis.

Acanthodian scapulocoracoids have also been identified, as well as tightly spiralled toothwhorls which could

be from an acanthodian.

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Authors and Affiliations

Carole J. Burrow
Szrek Piotr
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Abstract

Fourteen symposia on early/lower vertebrates have taken place over the last 50 years, usually at about four year

intervals. An average 60 participants have taken part at these symposia, with over one hundred occasionally. The

results of the symposia have been published in proceedings. The symposia started honoring E. A:son Stensiö and

E. Jarvik. Honors were taken up at the 11th symposium in Uppsala again. Since the 13th symposium a Stensiö

award is also given to young researchers in the field.

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Authors and Affiliations

Hans-Peter Schultze
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Abstract

Material of tesseraspids (Tesseraspidiformes) is reported from the uppermost Severnaya Zemlya Formation

(Lochkovian, Lower Devonian) of the Severnaya Zemlya archipelago, in the Russian Arctic, where it is associated

with other vertebrate remains, including corvaspids, acanthodians, and large but rare specimens of

osteostracans. The tesseraspid material is not abundant, and most often preserved as a “patchwork” of bony

platelets (tesserae), except for a few partly articulated specimens. We redescribe the holotype of Tesseraspis

mosaica Karatajūtė-Talimaa, 1983, whose head carapace is preserved as a flattened tube of adjacent tesserae.

This material is compared to the already published tesseraspid taxa, i.e., T. tessellata Wills, 1935, T. toombsi

Tarlo, 1964, T. mutabilis (Brotzen, 1934), T. oervigi Tarlo, 1964 emend. Dineley and Loeffler, 1976, T. denisoni

Tarlo, 1964, and T. talimaae Tarlo, 1965. All species are based upon rare and incomplete material, as no

head carapaces associated with trunk and tail are known, and so, the intraspecific variability is also unknown.

Distinction between “species” is based on the detail of the superficial sculpture of the tesserae of the head carapaces,

which is unsatisfactory. It is concluded that only four of the nominal species can be retained. A review

of all other known tessellated pteraspidomorphs indicates that our knowledge of tessellated heterostracans is

currently insufficient to support a meaningful classification.

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Authors and Affiliations

Blieck Alain
David K. Elliott
Valentina N. Karatajūtė-Talimaa
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Abstract

Placoid and polyodontode scales of stem chondrichthyans have been found in the early Lochkovian “Ditton

Group” of the Brown Clee Hill district, Shropshire, England and at Talgarth, south Wales. One of the forms is

assigned to a new species of Altholepis Karatajūtė-Talimaa, 1997, a genus already recognised from Lochkovian

shallow marine deposits in Celtiberia, Spain and the Northwest Territories, Canada as well as the type locality in

Podolia, Ukraine. Altholepis salopensis sp. nov. is based on small polyodontode scales with typically three to eight

high odontodes; the scale form was previously considered to belong to acanthodian “Nostolepis” robusta (Brotzen,

1934). The structure of other scales formerly assigned to “Nostolepis” robusta has led us to erect a new genus

Jolepis for this scale form, which differs from Altholepis in lacking an ordered layout of odontodes. Jolepis robusta

(Brotzen, 1934), originally (and possibly still) considered to be an acanthodian, is also known from the Baltic

countries, Russia, and northern Germany (ex erratic limestones). Scales of acanthodian Parexus recurvus Agassiz,

1845, and/or possibly from the stem chondrichthyan Seretolepis elegans Karatajūtė-Talimaa, 1968 (scales of these

two taxa are barely distinguishable), and of stem chondrichthyan Polymerolepis whitei Karatajūtė-Talimaa, 1968

are also present. Altholepis, Jolepis gen. nov., Seretolepis Karatajūtė-Talimaa, 1968 and Polymerolepis Karatajūtė-

Talimaa, 1968 are found in marine deposits elsewhere; the British occurrence of these taxa adds to the debate on

the sedimentological origins of the Lower Old Red Sandstone deposits in the Welsh Borderland. The geographic

range of several early sharks is now known to extend around the Old Red Sandstone continent and beyond.

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Authors and Affiliations

Carole J. Burrow
Susan Turner
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Abstract

Ischnacanthus gracilis (Egerton, 1861), the only ischnacanthiform acanthodian from the Lochkovian Lower

Old Red Sandstone of Scotland, is known from hundreds of specimens in institutional collections worldwide.

Despite this relative abundance, morphology and histology of its skeletal elements have rarely been investigated.

Surface details of spines, dental elements, and scales are often not visible in specimens because they are

usually split through the middle. We have examined a broad size range of fish, from 35 mm to 250 mm long.

Several intact (not split) specimens have been collected in recent years and acid-prepared to show fine details of

the dermal and dental elements. We have also used scanning electron microscopy of scales, jaws and dental elements,

denticles and fin spines, and serial thin sectioning of articulated specimens, to document their structure.

Some of our notable observations include: identification of ventral lateral lines, double-layered subtessellate

calcified cartilage forming the jaws, and the probable occurrence of extraoral tricuspid denticles on the jaws

of most fish. Examination of the size range, body proportions and dentition of institutional specimens gives no

support for recognising more than one species in the Midland Valley localities.

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Authors and Affiliations

Michael Newman
ORCID: ORCID
Carole J. Burrow
den Blaauwen Jan
Jones Roger
Davidson Robert
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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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Authors and Affiliations

Bartosz Soliński
Monika Stopa
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Abstract

Due to unfavorable factors, dangerous conditions occurred in the delivery of electric energy in Poland. This was the most serious incident of its kind since the 1980’s. Such a serious incident raised concern about the safety of the electric power system in the summer and led to the formulation of conclusions for the future. In this article, the author analyses the conditions, which caused that situation. Poland was experiencing a doubt in August 2015, which along with an extremely high maximum daily temperature created remarkably unfavorable conditions for power plants and decreased the capacity of overhead power lines. Such unfavorable metrological conditions occurred not only in Poland, but also in Central-Eastern and Western Europe. It is worth emphasizing that the safety of electric energy delivery was endangered only in Poland. The improper renovation and upkeep policies, as well as unplanned outages in power plants caused a significant decrease of available power in the National Electric Power System. Unscheduled flows between Germany and Poland ruled out the possibility of importing electric energy at such a critical time. The author presents the correlation between the maximum daily air temperature in the sweltering heat and an increase in the demand for electric energy. Overall, unfavorable conditions posed a threat in the delivery of electric energy in Poland. In this article, the author draws attention to the report from the Supreme Audit Office (Najwyższa Izba Kontroli – NIK) from 2014, which predicted such a dangerous situation. Unfortunately, that report remained unnoticed. The author formulated appropriate solutions in order to increase the safety of electric energy delivery in the summer and to prevent such occurrences in the future.

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Authors and Affiliations

Bartosz Sobik
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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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Authors and Affiliations

Krzysztof Sornek
Mariusz Filipowicz
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Abstract

From all the detonation parameters of explosives, “strength” – the capability to perform work is the most important for the user. The detonation of explosives in the blast hole is a quick and complicated process: first there is a detonation pressure causing the crushing of the rock in the vicinity of the explosive, then the pressure of the detonation products causes the cracking of the rock. The article presents the methods of determining the capability to perform work by explosives for civil use (dynamite and ANFO) used in the accredited Laboratory of Explosives and Electric Detonators Testing of the Experimental Mine “Barbara” of the Central Mining Institute – the lead block (Trauzl) method and the ballistic pendulum method. The aim of the research was to determine the relationship between the values of the capability to perform the work received in a ballistic pendulum method and a lead block method. As a result of the performed tests and the analysis of the results, the α-Pb coefficient was determined, which can be used to convert the value of the capability to perform work on the ballistic pendulum to the corresponding value of the capability to perform work in the lead block. At present, the Central Mining Institute is the only Notified Body of the European Union in the scope of Directive 2014/28 /EU, which has a station for smelting lead blocks and equipment and for determining the capability to perform work by explosives in lead blocks – this method was abandoned in other research units for testing with a ballistic pendulum and/or underwater test.

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Authors and Affiliations

Michał Szastok
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Abstract

Describing the gas boiler fuel consumption as a time series gives the opportunity to use tools appropriate for the processing of such data to analyze this phenomenon. One of them are ARIMA models. The article proposes this type of model to be used for predicting monthly gas consumption in a boiler room working for heating and hot water preparation. The boiler supplies heat to a group of residential buildings. Based on the collected data, three specific models were selected for which the forecast accuracy was assessed. Calculations and analyses were carried out in the R environment using “forecast” and “ggplot2” packages. A good quality of the obtained forecasts has been demonstrated, confirming the usefulness of the proposed analytical tools. The article summary also indicates for what purposes the forecasts obtained in this way can be used. They can be useful for diagnosing the correct operation of a heat source. Registering fuel consumption at a level significantly deviating from the forecast should be a signal to immediately diagnose the boiler room and the heat supply system and to explain the reason for this difference. In this way, it is possible to detect irregularities in the operation of the heat supply system before they are detected by traditional methods. The gas consumption forecast is also useful for optimizing the financial management of the property manager responsible for the operation of the boiler room. On this basis, operating fees or financial operations with the use of periodic surplus capital may be planned.

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Authors and Affiliations

Grzegorz Bartnicki
Bogdan Nowak
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Abstract

Economic development is strictly dependent on access to inexpensive and reliable energy sources based on diversified primary fuels. The strategic framework for the construction of the energy mix is defined in the Energy Policy of the State, the content of which, in terms of its mandatory elements, has been specified in the Energy Law. The task of the Energy Policy of the State is to create the shape of the future power sector, including designing the most advantageous regulatory, system and technical solutions guaranteeing the appropriate level of energy security of the country, monitoring of the system’s evolution and also designing and implementing changes aimed at the optimization of the functioning mechanisms. The vision of the development of the power system at the global level should also reflect changes in the formation of dispersed civil energy structures. Unfortunately, the results of the conducted analyses reveal existing imperfections of the data acquisition and information system, which should be used in the planning process. This issue is particularly important from the perspective of the dynamically developing concept of the energy self-sufficiency of communes and the emergence of energy clusters. The present paper describes the functioning of strategic planning in the field of the electric power system with an illustration of the improperly functioning mechanisms of information transfer in the context of the advancement of dispersed civil energy structures.

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Authors and Affiliations

Maciej Sołtysik
Sylwia Całus
Marcin Malec
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Abstract

The efficient protection (support reinforcement) of a wall and heading crossing ensures continuity of the production cycle, and that is a quick moving of the scraper conveyor to the wall. Using low or high bolting as a support reinforcement element in wall and heading crossings allows for the elimination of traditional methods of maintaining longwall-gate crossings, and therefore allows for the efficient use high performance modern wall complexes. The paper presents the long underground experience, of the Knurów–Szczygłowice mine of efficient support wall and heading crossing maintenance, which was bolted to the rock mass with the usage of two pairs of bolts, showing full technical and economical usefulness of this support reinforcement method. The article also highlights work safety and the increasingly common usage of endoscopies when specifying the range of crack areas which directly effects the proper choice in number, load-capacity and length of the used bolts. The underground studies the measurements of the reach of the zones of fracturing and roof stratification (using endoscopes and wire type stratification meters) and the laboratory tests (using the test stand) have allowed to determine the safety factor for maintenance of the longwall gangway crossing, directly resulting in the necessity to install additional reinforcement. The value of the safety factor Sbsc-ch greater than 1 is advantageous and safe, and the value less than or equal to 1 can lead to a significant deterioration of the conditions of maintenance of a wall and heading crossing which was bolted.

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Authors and Affiliations

Stanisław Duży
Piotr Głuch
Grzegorz Michalik
Adam Ratajczak
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Abstract

Having increasingly tightened geological and mining conditions in which the extraction of copper ore deposits in Poland is conducted, ensuring effective and safe mining is presently becoming a key task and a significant challenge for mine operators, mainly in the field of ground support systems being the equivalent for the new geological/mining conditions. As one may expect, these conditions shall be characterized by higher values of the primary stress tensor elements as well as the lower deformability and higher strength of the rock mass surrounding the copper ore body. T his means that in the near future, the rock bursts problem will become one of the most important issues deciding on the economy and safety within the newly developed mining areas. T herefore developing a novel effective ductile ground support systems which could be able to control the rock mass movement in squeezing and burst-prone rock conditions is recommended. T his type of requirement may fulfil only ductile or, in other words, the kinetic energy-absorbing systems, which permit slowing down a movement of violently ejected rock blocks. T his paper’s objective is to present the idea of the development of a new type of an effective and low cost ductile resin anchored rockbolt system with smooth and of the square cross-section steel rod is formed in coil shape of different pitch. T he developed bolt prototypes have been tested underground in the G-11 section of the Rudna mine. Results of the pull-out tests, involving different bolts’ shapes and different sliding materials set on the rockbolts’ rods, have proved those bolts’ efficiency as an element of the ductile support system.

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Authors and Affiliations

Witold Pytel
Piotr Mertuszka
Krzysztof Szeptun
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Abstract

Methane explosions are among the greatest hazards in the Polish coal mining industry and unfortunately continue to cause many catastrophes. The constant growth of the depth of coal exploitation in the conditions of the high concentration of mining causes the increase of absolute methane content and methane seam pressure from the mined seams. This situation directly affects the increase in the level of methane hazard in the underground work environment. It is therefore obvious to undertake intensive research that will allow for the development of appropriate solutions that help to exclude the risk of mining catastrophes resulting from the ignition and/or methane explosion. In addition to the development of methane hazard prevention methods, an indispensable element of this approach is a very accurate identification of the mechanisms of the combustion and explosion of this gas. The article presents the method of investigation and examples of results of methane explosions carried out in the 400 m experimental gallery of the Experimental Mine “Barbara” of the Central Mining Institute – the only large scale underground experimental facility in Europe. A n analysis has been performed of the influence of the methane release into mining workings on the distribution of the gas concentration and on the course of its explosion or combustion. The data collected characterizes thermodynamic phenomena that form the basis for determining the level of the explosion hazard. Large scale studies have also allowed to assess the risk of conditions that are sufficient for the development of a coal dust explosion initiated by methane explosions. The large scale of the experiments and the system of continuous recording of the course of the experiments allowed the specific characteristics of the methane explosion and burning in underground mining workings to be identified and isolated. For the first time, the course of experiments was recorded via a camera system deployed along the gallery.

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Authors and Affiliations

Krzysztof Cybulski
Zdzisław Dyduch
Robert Hildebrandt
Henryk Koptoń
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Abstract

The contemporary underground mining of raw minerals is more and more associated with geological and mining software packages which support the work of designers from the moment of the exploration of a deposit, determination of its size and quality, geological, hydrogeological and tectonic conditions, by planning the development and cutting of the deposit. Production planning is one of the most important activities carried out in the course of a mining project, because it allows to set specific production results of a mine in relation to a time unit, and then allows for a verification of the degree of completion of the assumed plan. At present, computer-aided design is applicable to daily or long-term output planning taking deposit, qualitative, quantitative and cost constraints into account. In the article, selected forms of ore deposits were presented. On the basis of several dozen boreholes up to 300m in length, an exemplary fragment of the ore cutting model using computer-aided design of mining works was presented. By using modern computer software - ABB MineScape with modular construction, the possibilities of improving the process of development of future exploitation areas have been determined. In particular, the arrangement of boreholes, based on which ones the cross sections were made with, present the exemplary lithostratigraphic thickness of layers, including the location of discontinuous deformations in the form of faults, and an ore bearing zone. For the block model, resources with priority for metal N o. 1 and 2 were calculated. I n the last section of the article, the cutting idea for a shallow ore deposit has been presented. The degree of effective use of the deposit has been analysed for the room and pillar mining method.

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Authors and Affiliations

Krzysztof Skrzypkowski
Waldemar Korzeniowski
Andrzej Gądek
Radosław Misiak
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Abstract

The assessment of a rock’s behaviour around excavations and the effectiveness of its reinforcement in underground ore mines is dependent on the performance of the rock-bolt and rock-mass interaction, which can be estimated on the basis of appropriately designed measurements. Based on the background of various measurements solutions described in the literature, concerning rock bolt monitoring methods, the authors proposed a new, original device for mass measurements in mine conditions. After examining the advantages and disadvantages of existing constructions, the article presents the essence, principle of operation and method of measuring anchor load in an underground excavation with the a instrument, indicator WK-2/8. The prototype has been carefully researched and successfully tested in a full-scale laboratory environment. This instrument, also referred to as a load indicator or force pad, does not require electrical power and allows for relatively accurate (with a resolution of 10-14kN, up to about 90kN loading capacity) and a remote reading of the axle loading of the anchor (AGH patent) by any person present in the specified area. The device can be installed in mining excavations under loading conditions. The relatively low cost of a measuring instrument, practically used as an additional washer, as well as an easy assembly method, makes it universally applicable in mines where anchoring is used as a means of strengthening the rock.

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Authors and Affiliations

Waldemar Korzeniowski
Krzysztof Skrzypkowski
Łukasz Herezy
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Abstract

The paper presents differences between technical states and technical operation states of haul trucks in the technical operation process. The specification and analysis of operational parameters of technological vehicles used in surface mining is possible only due to more and more frequently used diagnostic – telemetric systems. While a detailed analysis of machines operation data can result in the more effective management of mining plant operations and the mining process itself. The determination of operational state indices and their individual components allows preventive actions to be commenced, resulting in improving the work organization of the entire mine machinery system. Moreover, the future technical state of machines operated in surface mining is strictly related to the current state and also depends on the events that occurred in the extraction system. A set of parameter values of individual state characteristics, which allow the haul trucks technical and operational state to be characterized, is a direct effect of a telemetric – diagnostic system operation.

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Authors and Affiliations

Przemysław Bodziony
Michał Patyk
Zbigniew Kasztelewicz
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Abstract

In recent years, the outsourcing of a variety of different activities has been more commonly observed in the coal mining industry. This is connected with employing workers by external companies. These practices are not necessarily perceived as good ones by mines’ employees because they may influence their remuneration directly or indirectly. Firstly, as external employees treat work in mining company as a source of a quick income. Therefore, external companies often calculate their employees compensation not based on working time (i.e. hours) but on the basis of a specific, accomplished task. Such employment is called piecework, whereas the workers employed in this kind of system are called output workers/piece workers. Therefore, to receive higher wages in these companies, employees carry out their tasks faster and more efficiently. This, in turn, can affect the standards of workers employed by the mining company. In addition, outsourced workers are often retired miners, so the costs incurred by employers are significantly lower. In addition, in order to not to lose the retirement benefit, they work for a much lower rate. On the other hand, outsourced work can be done in a hurry (on a piece rate), which is not conducive to compliance with safety regulations, therefore mine employees may feel unsafe. This article aims to present how mine employees assess outsourcing underground works. In order to achieve this aim, a survey was carried out among employees of one of the coal mine companies in Silesia. Participants of the survey were randomly chosen among underground miners employed at one mine company. The survey was anonymous which obviously might have influenced respondents’ honesty in answering. The survey was carried out in several mines of the chosen company. In some of them the survey was carried out online and in the remaining ones it was filled out on paper. Analyzing the survey results allowed for a better understanding of the reasons of the disapproval of outsourcing underground works. This, in turn, may be used for better human resources management including, in particular, planning an incentive based pay system.

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Authors and Affiliations

Ewelina Włodarczyk
Aurelia Rybak
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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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Authors and Affiliations

Aurelia Rybak
Ewelina Włodarczyk
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Abstract

According to The European Commission’s regulation numbers 842/2006 and 517/2014, refrigerants whose Global Warming Potential ratio is more than 150, have been prohibited in mobile air conditioning (MAC) since January 2017. Therefore, the commonly used R-134 gas has been banned. The search for a new refrigerant, which grants all the required criteria, has begun. In accordance with new European standards, the gas should have environmentally friendly properties and should not be noxious to human life while operating. In this paper, two alternative substances, which can substitute the banned R134a, have been compared. This is synthetic R1234yf, which belongs to the HFO group, and carbon dioxide, which exists in the natural environment. The chemical build, physical and thermodynamic properties have been described. Scientific articles, which present and compare the technical results of testing both refrigerants, have been discussed. Comparison results, tools used and research methodology have been described in these articles. Alternative gases have been analyzed for their environmental impact and have been checked on the toxic, flammable, impact on ozone depletion and global warming. The threats to human life due to the use of the new refrigerants have been reviewed. The thesis also comprises an economical comparison between the two gases. A short review and conclusions have been presented at the end of the article.

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Authors and Affiliations

Artur Bieniek
Michał Pysz
Łukasz Mika
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Abstract

Blockchain is a technology, which could revolutionize many industries in the future. A system like that is based on a chain of blocks that is used for storing and transferring various data, forming a decentralized ledger. Although various fundamental projects based on the blockchain system in the energy industry are in their early stage of development, as well as other solutions, applications of blockchain technology in the broadly understood power engineering sector are considered to have a very large potential. This paper presents a brief description of the blockchain technology, its general operating principle and the possibilities it brings. The next section of the article contains a characterization of two exemplary and possible blockchain technology applications, which in the perspective of time may have a significant impact on the power engineering sector. The first solution is related to carrying out energy transactions, which could be conducted in an easy way directly between energy producers and consumers. Thanks to blockchain technology, this could lead to a partial decentralization in that area. The second proposed example concerns energy resources origin tracking, which would allow fixed origin attributes and parameters affecting the environment to be assigned to the generated energy. By implementing that solution, it would be possible to construct a fuel footprint of individual generating units. The article also mentions examples of other potential applications of blockchain technology in the power engineering sector.

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Authors and Affiliations

Daniel Mrowiec
Michał Sołtysik
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Abstract

Tribal fragments of the Cumans, a people of the Eurasian steppe region, appeared in the medieval kingdom of Hungary in the early 13th century, on the eve of the Mongol Invasion. Many of them permanently settled in the Great Hungarian Plain, and their community had to undergo profound transformations both in terms of social and economic strategies. Mobile pastoralism, often associated with the Cuman communities of the steppe, was definitely impossible in their new homeland. However, animal husbandry remained the most important economic activity in this part of the Carpathian Basin in the centuries after the Cumans’ arrival. This paper provides a case study on the region called Greater Cumania in the Great Hungarian Plain, and especially on one Cuman village, Orgondaszentmiklós, where 14th–16th-century habitation layers were brought to light. Archaeological and written evidence for animal husbandry is analyzed in order to establish patterns of integration or specialization in terms of animal herding. The results show that although some preferences that may have been rooted in steppe tradition were retained, the main factor in economic orientation was the position in the settlement network and the connection to markets. Swine keeping, a tradition virtually non-existent in the steppe area, was adapted relatively quickly as a response to available natural resources (marshlands) in the area. It seems, on the other hand, that horses preserved their high social value and their flesh was also consumed.

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Authors and Affiliations

Kyra Lyublyanovics
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Abstract

An Arpadian age (10th–11th c.) burial ground was unearthed on the plateau of Oberleiserberg along with features and findings from several other periods. It was first discovered during the excavation led by Herbert Mitscha-Märheim and Ernst Nischer-Falkenhof in the 1920s and 30s. In the 1970s and 80s the site was archaeologically investigated by Herwig Friesinger and his team. During these archaeological campaigns 71 additional graves were found. The multidisciplinary analyses of the medieval findings and features as well as the human remains unearthed on Oberleiserberg are part of the international project Frontier, Contact Zone or No Man’s Land — The Morava- Thaya Region from the Early to the High Medieval Ages (I 1911 G21, led by Stefan Eichert and Jiří Macháček funded by FWF (Austrian Science Fund) and GAČR (Czech Science Foundation). The early and high medieval findings indicate contact of the entombed population with nonnative peoples, possibly reaching as far as the Baltic Sea. Anthropological analysis of the excavated skeletons shows us more about the everyday life of the people buried here and together with isotopic analysis of the human remains, conclusions about their living conditions are possible.

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Authors and Affiliations

Nina Brundke
Stefan Eichert
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