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Abstract

New types of models can help us better predict how well species will be able to adapt to climate change.
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Authors and Affiliations

Katarzyna Sękiewicz
1

  1. Department of Biogeography and SystematicsInstitute of Dendrology PAS in Kórnik
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Abstract

The paper presents selected aspects of dynamic numerical simulations of an orthotropic steel railway bridge loaded by high-speed trains. The model of moving loads was adopted in accordance with the models set out in the applicable standards. The current European code requirements are referred in which the computer calculations of the dynamic response of the structure are the basis for assessing the suitability of the structure to carry high-speed rail traffic ( v > 160 km/h ). In this research the calculations are based on the author's method of generating traffic roads in Abaqus FEM environment. lt is emphasized in the paper that in most commercial FEM codes (including Abaqus), moving loads are not implemented in modules responsible for defining of loads. The author's approach to this issue allowed to obtain results confirming its adequacy. In the longer term, the authors will develop a plan to adapt this algorithm in order to generale traftic loads on bridges discretized as spatial and plane numerical models.

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Authors and Affiliations

A. Zbiciak
R. Oleszek
R. Michalczyk
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Abstract

This paper presents an evaluation of the Hypoplastic Clay constitutive model for finite element analysis of deep excavations and displacements induced by excavations in the influence zone. A detailed description and formulation of the Hypoplastic Clay soil model is included. A parametric case study of a deep excavation executed in Pliocene clays is presented. FE analysis was performed using several soil models (Mohr-Coulomb, Modified Mohr-Coulomb, Drucker-Prager, Modified Cam-Clay, Hypoplastic Clay) and the results were compared to in-situ displacements measurements taken during construction. Final conclusions concerning the suitability of the Hypoplastic Clay model for deep excavation modelling in terms of accurate determination of horizontal displacements of the excavation wall, the uplift of the bottom of excavation, and, most importantly,vertical displacements of the terrain in the vicinity of the excavation are presented.

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Authors and Affiliations

M. Mitew-Czajewska
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Abstract

Geomechnical model testing has been widely applied as a kind of research technique in underground engineering problems. However, during the practical application process, due to the influence of many factors, the desired results cannot be obtained. In order to solve this problem, based on the measurement requirements of the model test, combined with FBG(Fiber Bragg Grating) sensor technology and traditional measurement methods, an FBG monitoring system, Micro-multi-point displacement test system, resistance strain test system and surrounding rock pressure monitoring system are developed. Applying the systems to a model test of the tunnel construction process, the displacement in advance laws of tunnel face, radial displacement distribution laws and surrounding rock pressure laws are obtained. Test results show that a multivariate information monitoring system has the advantage of high precision, stability and strong anti-jamming capability. It lays a solid foundation for the real-time data monitoring of the tunnel construction process model test.

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Authors and Affiliations

Q. Liu
J. Chen
L. Wei
P. Huang
Y. Luo
X. Pu
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Abstract

The article presents the use of the Mamdani fuzzy reasoning model to develop a proposal of a system controlling partnering relations in construction projects. The system input variables include: current assessments of particular partnering relation parameters, the weights of these parameters’ impact on time, cost, quality and safety of implementation of construction projects, as well as the importance of these project assessment criteria for its manager. For each of the partnering relation parameters, the project’s manager will receive controlrecommendations. Moreover, the parameter to be improved first will be indicated. The article contains a calculation example of the system’s operations.

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Authors and Affiliations

E. Radziszewska-Zielina
B. Szewczyk
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Abstract

Commercialization processes are modeled and analyzed from the point of view of the implementation of activities under particular stages. These issues are the subject of many studies and analyzes, which is why the extensive literature is available on this subject. Technology valuation at various stages of the commercialization process is a separate issue. Such valuation is prepared in most cases by consulting companies for determining the price in the buying and selling processes. These valuations use known methods also used in other cases, e.g., real estate valuation. The work carried out presents the author’s concept of the commercialization process model, taking into account the costs and value of the technology at various stages of the product life cycle. The model uses a stochastic approach to determine future revenues and costs, which allows estimating the value of the technology by or in determining the probability of assessment validity. The proposed stochastic approach greatly increases the chances of using the presented solutions in practical activities related to technology valuation for the purposes of purchase and sale transactions.
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Authors and Affiliations

Bozena Kaczmarska
1
Wacław Gierulski
1
ORCID: ORCID
Josef Zajac
2
Anton Bittner
2
Wacław Gierulski
1

  1. Kielce University of Technology, Poland
  2. Technical University of Kosice, Slovakia
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Abstract

The object of the present study is to investigate the influence of damping uncertainty and statistical correlation on the dynamic response of structures with random damping parameters in the neighbourhood of a resonant frequency. A Non-Linear Statistical model (NLSM) is successfully demonstrated to predict the probabilistic response of an industrial building structure with correlated random damping. A practical computational technique to generate first and second-order sensitivity derivatives is presented and the validity of the predicted statistical moments is checked by traditional Monte Carlo simulation. Simulation results show the effectiveness of the NLSM to estimate uncertainty propagation in structural dynamics. In addition, it is demonstrated that the uncertainty in damping indeed influences the system response with the effects being more pronounced for lightly damped structures, higher variability and higher statistical correlation of damping parameters.

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Authors and Affiliations

B. Tiliouine
B. Chemali
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Abstract

This study aims to design a novel air cleaning facility which conforms to the current situation in China, and moreover can satisfy our demand on air purification under the condition of poor air quality, as well as discuss the development means of a prototype product. Air conditions in the operating room of a hospital were measured as the research subject of this study. First, a suitable turbulence model and boundary conditions were selected and computational fluid dynamics (CFD) software was used to simulate indoor air distribution. The analysis and comparison of the simulation results suggested that increasing the area of air supply outlets and the number of return air inlets would not only increase the area of unidirectional flow region in main flow region, but also avoid an indoor vortex and turbulivity of the operating area. Based on the summary of heat and humidity management methods, the system operation mode and relevant parameter technologies as well as the characteristics of the thermal-humidity load of the operating room were analyzed and compiled. According to the load value and parameters of indoor design obtained after our calculations, the airflow distribution of purifying the air-conditioning system in a clean operating room was designed and checked. The research results suggested that the application of a secondary return air system in the summer could reduce energy consumption and be consistent with the concept of primary humidity control. This study analyzed the feasibility and energy conservation properties of cleaning air-conditioning technology in operating rooms, proposed some solutions to the problem, and performed a feasible simulation, which provides a reference for practical engineering.

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Authors and Affiliations

X.R. Ding
Y.Y. Cino
Y.Y. Chen
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Abstract

The aim of this study is to find the cost design of RC tension with varying conditions using the Artificial Neural Network. Design constraints were used to cover all reliable design parameters, such as limiting cross sectional dimensions and; their reinforcement ratio and even the beahviour of optimally designed sections. The design of the RC tension members were made using Indian and European standard specifications which were discussed. The designed tension members according to both codes satisfy the strength and serviceability criteria. While no literature is available on the optimal design of RC tension members, the cross-sectional dimensions of the tension membersfor different grades of concrete and steel, and area of formwork are considered as the variables in the present optimum design model. A design example is explained and the results are presented. It is concluded that the proposed optimum design model yields rational, reliable, and practical designs.

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Authors and Affiliations

N. Karthiga Shenbagam
N. Arunachalam
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Abstract

This paper presents an approach based on NURBS (non-uniform rational B-splines) to achieve a seismic response surface (SRS) from a group of points obtained by using an analytical model of RC joints. NURBS based on the genetic algorithm is an important mathematical tool and consists of generalizations of Bezier curves and surfaces and B-splines. Generally, the accuracy of the design process of joints depends on the number of control points that are captured in the results of experimental research on real specimens. The values obtained from the specimens are the best tools to use in seismic analysis, though more expensive when compared to values simulated by SRSs. The SRS proposed in this paper can be applied to obtain surfaces that show site effect results on destructions of beam-column joint, taking into account different site conditions for a specific earthquake. The efficiency of this approach is demonstrated by the retrieval of simulated-versus-analytical results.

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Authors and Affiliations

R. Tabatabaei Mirhosseini
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Abstract

Deriving the formulas for strain components, we are assuming, that cross-section of a rod being rotated in space during deformation does not need to be perpendicular to deformed centroid line. This not a quite intuitive assumption allows for more compact and easier formulas for strain tensor or equilibrium equations. Derived transformations between actual and initial coordinate system, components of strain tensor and virtual works principle for investigated spatially curved beams of bisymmetric cross-section are shown in this paper. Conformity with other models from referenced literature is also shown.

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Authors and Affiliations

R. Bijak
G. Kołodziej
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Abstract

The Author comments on a new book by Mariusz Mazur O człowieku tendencyjnym... — a book on the communist endeavour to create a new man. He considers the book excellent. Its important positive point is the analysis of the theme in a large framework of human history. Communism was a very singular regime but the idea of a new man appeared several times through centirues and in different countries.
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Authors and Affiliations

Marcin Kula
ORCID: ORCID
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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 heat supply systems energy efficiency improvement requires the use of increasingly complex methods. The basic ways to reduce heat consumption is by using better thermal insulation, although they have more and more limited possibilities and need relatively large financial outlays. Good effects can be achieved by the better heat source adaptation to the conditions of a specific facility supplied with heat. However, this requires research that identifies the effectiveness of such solutions as well as the tools used to describe selected elements of the system or its entirety. The article presents the results of tests carried out for a gas boiler room supplying heat to a group of residential buildings. The goal was to build a model that would forecast the day range in which the maximum gas consumption occurs for a given day. Having measurements of gas consumption in subsequent hours of the day, it was decided to build a forecasting model determining the part of the day in which such a maximum would occur. To create the model the random forest procedure was used along with the mlr (Kassambara) package. The model’s hyperparameters were tuned based on historical data. Based on data for another period of boiler room operation, the results of the model’s quality assessment were presented. Close to 44% efficiency was achieved. Tuning the model improved its predictive ability.

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Authors and Affiliations

Bogdan Nowak
Grzegorz Bartnicki
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Abstract

The article presents some possibilities and limitations of the general psychological knowledge utilization in the causal explanation in history based on the probabilistic model.
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Authors and Affiliations

Maciej Dymkowski
ORCID: ORCID
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Abstract

In the research on historic, composed green areas various computer technologies are applied, including among others reconstruction ideograms and virtual spatial models. They are created on the basis of historical cartographic materials, among which Prussian maps Urmesstichblatts and Messtischblatts deserve special attention as they provide extraordinarily useful and often otherwise unavailable information concerning the system of spatial composition.

The article presents a method of procedure on the example of selected research objects. Such studies are extremely useful in the process of research, analyses and documentation of the authentic state of historical sites. Moreover, they provide a significant material for further analyses concerning revalorisation and creation of the cultural landscape.

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Authors and Affiliations

Piotr Urbański
Miłosz Walerzak
Agnieszka Wilkaniec
Agnieszka Rosada
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Abstract

Architecture changes the environment. This process generates permanent, long-term effects and limits future development. The paper presents the impact of model methodology on the ability to predict the consequences of architectural designs and realizations. The categories of threats and model simulation strategies were ordered. The significance of the digital breakthrough in modeling is outlined in historical perspective and opportunities the paradigm shift creates are characterized.
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Authors and Affiliations

Jan Słyk
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Architecture
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Abstract

The article will consider research directions on a social history of disability based on the social and the human-rights models of disability, as well as the concept of disability included in the UN Convention on the Rights of Persons with Disabilities. The article contains the basic methodology of historical research on the subject, the main research fields, and an overview of primary sources. In addition, the periodisation of the subject was introduced.

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Authors and Affiliations

Zbigniew Głąb
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Abstract

The rapid development of the global economy has led to an increasing demand for resources. The disparity between the supply and demand of resources continues to be prominent and shows a situation of short supply. Resource investment projects with large amounts and long construction periods face many risks due to various unpredictable factors. Cultural, legal, economic and other environments vary between different countries. Therefore, comprehensive risk identification, understanding, evaluation, and analysis are important prerequisites for the success of mineral investment. In this paper, the risk of mineral resources investment in host countries is identified. A risk evaluation index system is established to objectively evaluate the risk environment of the host country. The risk evaluation index system includes four first-level indexes: political and legal risk, social and cultural risk, economic and financial risk, and natural risk. The subjective weight was determined by sending questionnaires to experts and scholars in the industry and conducting data processing. The entropy method was used to determine the objective weight. Finally, the subjective weight and the objective weight were combined to obtain a group of scientific and accurate combined weights. The matter-element theory was introduced into the cloud model and a risk assessment model based on the cloud matter-element theory was constructed with comprehensive consideration of the fuzziness and randomness of risks. Eight countries with relatively rich mineral resources were taken as cases to verify the model application. The research results provide a theoretical basis and decision-making methods for mineral enterprise investment.
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Authors and Affiliations

Jie Hou
1
Guoqing Li
1
Jiahong Ling
1
Lianyun Chen
2
Wei Zhao
3
ORCID: ORCID
Baoli Sheng
3

  1. University of Science and Technology Beijing, China
  2. University of Science and Technology Beijing, China; Shandong Gold Group Co., Ltd., Jinan, China
  3. Sanshandao Gold Mine, Shandong Gold Group Mining (Laizhou) Co., Ltd., Yantai, China
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Abstract

This article presents the results of research on the importance of access to critical raw materials for the development of wind energy in Poland. The authors have built a set of factors that can potentially influence this development. Twenty-four explanatory variables were taken into account, which were assigned to five categories. The amount of demand for mineral resources related to the development of wind technology was determined using a computer programwritten by the authors. The importance of individual factors was verified using the ARMAX model. As a result of this, it was possible to identify the explanatory variables that significantly affect the volume of wind energy production in Poland. The group of mineral resources includes critical metals that are necessary for the production of wind turbines. These are rare earth elements, copper, nickel, boron and manganese. The ARMAX model enables the examination of the relationship between the explained variable and the explanatory variables. Optimization of the model parameters was performed by limiting the mean square error. During the validation of the model, the VIF (variance inflation factor), Dickey-Fuller and Doornik-Hansen tests were used. The ARMAX validation also consisted of selecting the model characterized by the lowest value of information criteria and determining ex post errors, including the mean absolute percentage error (MAPE). In addition, the nature of individual independent variables was determined, i.e. whether they were stimulants, nominants, or destimulants. The forecast made it possible to verify the possibility of meeting the assumptions of the Polish Energy Policy until 2040. It showed that if the development trends of the factors that affect wind energy do not change, it would be possible to meet the assumptions of PEP2040 regarding the dynamic development of wind farms in Poland and double the generation capacity by 2030. Analysis using the ARMAX model showed that access to raw materials such as REE, Cu, Ni, Br and Mn would have a very significant impact on the development of wind energy in Poland. Each factor of the raw material category that was introduced into the model was considered statistically significant at the significance level of α = 0.01, i.e. at the lowest acceptable risk of error. Therefore, the raw material base would be of key importance to ensure access to wind energy at the level adopted in PEP2040.
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Authors and Affiliations

Aurelia Rybak
1
ORCID: ORCID
Aleksandra Rybak
1
ORCID: ORCID

  1. Silesian University of Technology, Gliwice, Poland
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Abstract

The mathematical modeling of mineral processing is a very complex task because of random character of comminuted materials. However, it allows applying of standard laws of mass preservation and mass transport. The basic method of description of comminution processes is determination of particles size distribution curves for products. In the paper, the concept of applying so-called censored distribution functions was presented, what means equations of exponential, Weibull, log-normand logistic distribution functions as the basis of crushers work description (formulas 1, 2, 3 and 4). The censoring of distribution functions is being realized through acceptation of maximum particle size dmax and the shape of them depends on shape and scale parameters. The joining of technical parameters of comminuting devices with parameters of equations describing distribution functions of products allows creating of satisfying models of comminution processes. After application of general forms of separation curves the description of sieving processes is possible (equations 6a and 6b) and then also of comminution systems. The optimization of aggregates production may be based on introduction of goal function determining profit dependably on amount of individual assortments. In case of analysis of comminution systems (formulae 10) in preparation of feed to beneficiation the goal function should be based on levels of useful minerals exposure in individual fractions. The paper shows the possibility of simulation of comminution processes course leading to determination of optimal conditions of systems containing comminution and sieving processes. Furthermore, the necessity of creation of empirical models for grinding processes was shown as they would be the compensation of models being result of heuristic analysis of phenomena. Also, the elementary rules of selection of models forms and their modifications based on justification of relations between distribution function parameters and basic technical parameters of devices as well characteristics of comminuted materials were discussed. The paper is the introduction to further research of general approach to joining grained materials characteristics with comminution effects.

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Authors and Affiliations

Tadeusz Tumidajski
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Abstract

The aim of the paper is to discuss the existing CLIL models with respect to how they are used by teachers in Polish lower–secondary education. Throughout the paper a general situation in the system of education concerning bilingual classrooms is depicted with the focus on four CLIL models traditionall used in contemporary schools. The overall objective is to analyse the popularity of languages employed as the medium of instruction in bilingual provision, the subjects whose content is imparted through the medium of a foreign language as well as the four major curricular models themselves developed and implemented for the needs of bilingual programmes in the Poland.

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Authors and Affiliations

Piotr Romanowski
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Abstract

The paper presents historical concepts and paradigms of the institution of university as well as its present and future models.

As a starting point, the origin, structure and function of the medieval university are discussed; then, four basic concepts of university formed in the 19th century are given, namely the German model of Wilhelm Humboldt and Johann Fichte, the English model of Cardinal Newman, the American model formed aft er foundation of the John Hopkins University and the French model – the Napoleonic model ofuniversity.

What follows is an analysis of the changes and evolution of universities in the 20th century. It is indicated that the essence of today’s university is composed of the following activities: didactics, research and professional training. A great significance of general and formal education is also emphasized. Th e priority is given to practising basic disciplines at universities and the significance of the humanities for general education of students, including philosophy, theology and ethics is stressed.

The author is warning us against single-discipline education in a situation when all contemporary problems, whether economic, political, social, ethical or technical, can only be solved on the interdisciplinary basis via cooperation of experts in different fields. The gap between visions of the world shaped by natural sciences and the humanities should be gradually bridged. To this end, a paradigm of the future university is put forward. The paradigm should provide for cultivation of the values derived from the Classical University rooted in the Greco-Roman and Christian tradition, mathematical exactness of scientific research and quality professional training of the Positivist University, as well as the ecological and holistic vision and education of the youth, in a spirit of tolerance of the Postmodern University.

The paradigm of the university of the future should encompass three significant elements, i.e. the mission of a contemporary academic school, the conditions in which it is functioning and the rules it should follow. The paper indicates that, though destined to an ongoing change, the mission of universities for centuries has featured the same components, namely intellectual and ethical education of the youth and scientific research. The contemporary university should act as “the eyes of the world” that perceive its main problems and provide guidance in solving them.

The contemporary university must duly take into account the external conditions, namely globalisation, multiculturalism, ecological threats, rapid communications and technological progress, a growth of negative social phenomena such crime, moral degradation and terrorism; a growing infl uence of the media on life of societies, anti-intellectualism, relativism and radical individualism triggered by the Post-modem era. The rules that a contemporary academic school should act in accordance with are given as follows: a quest for the highest standards in didactics, research and other activities; full freedom of scientifi c research; a focus on discovering the truth and sharing it with others; ethical responsibility of scholars and university professors; the spirit of duty in education; forming amicable and stable academic communities; partnership in cooperation with other scholars and universities; aiming at the integration of Christian knowledge and faith.

The paper ends with a citation from Pope John Paul’s II. address to the chancellors of all Polish academic schools in 1997, in which he stressed the role of ethical sensitivity of scholars today, owing to which the bond may be maintained both between the True and the Good and the freedom of scientific research and ethical responsibility for its outcomes.

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Authors and Affiliations

APB Stanisław Wielgus
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Abstract

The paper presents the idea of a prosumer energy cloud as a new service dedicated to electricity prosumers. The implementation of the cloud should generate a number of benefits in the following areas: settlements between prosumer and electricity supplier, the development of distributed energy sources in microprocessors and the development of e-mobility. From the prosumer point of view, the proposed idea of a prosumer cloud of energy is dedicated to the virtual storage of energy excess generated in the micro-installation. Physical energy storage in the cloud means recording the volume of electricity introduced into the electricity system from the prosumer’s microprocessors. It is assumed that the energy equivalent to the volume registered in the prosumer cloud can be used at any time at any point in the network infrastructure of the National Power System. Any point of network infrastructure shall be understood as any locally located point of connection of an electricity consumer provided with access authorization. From the point of view of the power grid operators, the idea of a prosumer energy cloud is a conceptual proposition of a service dedicated to the new model of the power system functioning, taking future conditions concerning the significant development of prosumer energy and e-mobility into account. In this concept, electricity would be treated as a commodity only to partial physical storage and above all to trade. In this model a key aspect would be virtual energy storage, that is, the commercial provision by the cloud operator (trading company) of any use of the electricity portfolio by its suppliers. It should be stressed, however, that in the prosumer’s energy cloud functioning, a significant factor would be the cost of guarantees of the use of energy by prosumers at any time and point of connection to the network. This results in the need of taking the presence of certain market risks, both volumetric and cost incurred by clouds operator, which can be minimized by passing a portion of the accumulated volume of generated energy to the cloud operator into account. It should be emphasized that this article presents the first phase of the development of the concept of prosumer energy cloud. However, it is planned to be expanded by the following stages, which include the possibility of controlling and supervising the operation of prosumer installations such as: sources, receivers and physical energy stores, e.g. home energy storage or batteries installed in electric vehicles. Ultimately, it is assumed that the proposed prosumer energy cloud will be outside of the storage of energy (virtual and partly physical) and that aggregation of prosumer resources will create new possibilities for their use to provide a variety of regulatory services, including system ones.

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Authors and Affiliations

Piotr Rzepka
Maciej Sołtysik
Mateusz Szablicki

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