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Number of results: 133
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Abstract

In the summers of 1978 and 1979 meteorological observations and measurements were carried out in South Spitsbergen. These investigations gave a characteristic of the summer meteorological conditions in the forefield of the Gås Glacier. Some regularities were found to exist in the distribution of air temperature and other meteorological elements.

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Authors and Affiliations

Andrzej Kamiński
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Abstract

Temporal differentiation of the air thermal conditions in SW part of Spitsbergen has been presented in this paper. Daily meteorological records of the Polish Polar Station of the Polish Academy of Sciences in Hornsund have been used for the period of 1978—1986. Distributions of basic thermal indices based on mean, maximum, minimum air temperatures and minimum temperature at a ground surface have been given. Annual patterns of the above elements of various occurrence probabilities have been also presented and thermal periods have been distinguished.

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Authors and Affiliations

Zbigniew Ustrnul
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Abstract

Multidisciplinary research was carried on in 1978/79 in the region of Admiralty Bay and Arctowski Station. This area is representative of the near-shore Antarctic ecosystem. It is characterized by a number of local traits such as climate, ice conditions, hydrology, hydrochemistry and hydrodynamics. Estimates were made of primary production and abundance of zooplankton in Admiralty Bay and of the biomass and quantity of food taken by avi-fauna and pinnipeds. Main routes and directions of transport of mineral and organic matter are shown; some of them have been estimated quantitatively. A continuous inflow of organic matter from Bransfield Strait is necessary for the summer functionning of Admiralty Bay.

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Authors and Affiliations

Stanisław Rakusa-Suszczewski
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Abstract

The aim of this article is to defi ning problems occurring in the spatial management system, including those independent of subsequent legislative changes. The process of adopting decisions to be viable and socially equitable and execute the requirements of spatial order and sunstainable development requires fundamental changes. The study draws a conclusion – important in the context of subsequent research activities – that the varied application of development decisions in diff erent municipalities is also the result of not preparing a large part of the representatives of municipalities for specifi c spatial activities.

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Authors and Affiliations

Maciej J. Nowak
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Abstract

Thermal imagers often work in extreme conditions but are typically tested under laboratory conditions. This paper presents the concept, design rules, experimental verification, and example applications of a new system able to carry out measurements of performance parameters of thermal imagers working under precisely simulated real working conditions. High accuracy of simulation has been achieved by enabling regulation of two critical parameters that define working conditions of thermal imagers: imager ambient temperature and background temperature of target of interest. The use of the new test system in the evaluation process of surveillance thermal imagers can bring about a revolution in thermal imaging metrology by allowing thermal imagers to be evaluated under simulated, real working conditions.
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Authors and Affiliations

Krzysztof Chrzanowski
1 2
ORCID: ORCID

  1.   Institute of Optoelectronics, Military University of Technology, gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland
  2. INFRAMET, Bugaj 29a, Koczargi Nowe, 05-082 Stare Babice, Poland
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Abstract

Small construction objects are often built by standard task teams. The problem is, how to allocate these teams to individual works? To solve the problem of allocation three methods have been developed. The first method allows to designate optimal allocation of teams to the individual works in deterministic conditions of implementation. As a criterion of the optimal allocation can be applied: “the minimization of time” or “the minimization of costs” of works execution. The second method has been developed analogously for both criteria but for stochastic conditions and for the stochastic data. The third method allows to appoint a compromise allocation of teams. In this case, the criteria “the minimization of time” and “the minimization of costs” are considered simultaneously. The method can be applied in deterministic or stochastic conditions of works implementation. The solutions of the allocation problems which have been described allow to designate the optimal allocation of task teams and to determine the schedule and cost of works execution.

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Authors and Affiliations

T. Kasprowicz
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Abstract

Managing human consumption has a major impact on the functioning of societies, and – even more importantly – on the condition of our planet. What does the future hold?

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Authors and Affiliations

Jan Marcin Węsławski
ORCID: ORCID
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Abstract

The advance of technical state criteria for elements of mining hoists demands a basic strength-fatigue analysis where the real values of loads and the real time function of the load variability could be used. That problem concerns also the suspension gear of skip and balance ropes, where fatigue durability should be considered as time function related to the hoist facility type. Such objective can not be achieved without comprehensive study of the dynamics of processes both in the regular operation of the facility and in its emergency states. In this work the author presents some considerations, that are however, limited to the analysis of dynamic phenomena observed in the condition of the emergency braking of the hoist facility. The results were verified by load measurements taken for some elements of the analysed real object system.
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Authors and Affiliations

Stanisław Wolny
ORCID: ORCID
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Abstract

This study gives an analysis of the variation of main meteorological parameters on the Station Arctowski in the time from December 1979 through March 1980 — the summer season of the IV Antarctic Expedition of the Polish Academy of Sciences. Characteristics of wind speed and direction, of air temperature, atmospheric pressure, precipitation, cloudiness, soil temperature at the station and surface water temperatures of the Admiralty Bay are based on the standard synoptic observations.

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Authors and Affiliations

Barbara Cygan
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Abstract

Ground temperature measurement results in main ecotopes of the Kaffiöyra coastal plain (Oscar II Land, northwestern Spitsbergen): sea beach, tundra and morainic plateau, are presented and discussed in the paper. The spatial distribution of thermal conditions is discussed with particular regard to temperature of the active surface and vertical gradients of temperature dependent on daytime and weather conditions.

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Authors and Affiliations

Gabriel Wójcik
Kazimierz Marciniak
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Abstract

With reference to the situation experienced in several Polish collieries where the risk of occurrence of gas-geodynamic phenomena is increasing and decisions to start the mining activities need to take numerous constraints associated with previous mining into account, this paper addresses certain geo-mechanical aspects of longwall mining in the zones of excavation edge interactions giving rise to major changes in the conditions of the deposit and rock strata, as a consequence of previous mining operations in adjacent coalbeds. Starting from the analytical description of displacements and stresses in the proximity of longwall mining systems, the paper summarizes the results of model tests and investiga-tions of the influence that the excavation edge has on the behavior and structural continuity of a portion of the coal body in the coalbed beneath or above an old excavation. Based on selected nonlinear functions emulating the presence of edges in the rock strata, a comparative study is carried out by investigating two opposite directions of workface advance, from the gob area towards the coal body and from the coal body towards the gobs. The discussion of the results relies on the analysis of roof deformation and the concentration factor of the vertical stress component at the workface front.

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Authors and Affiliations

Dariusz Chlebowski
Zbigniew Burtan
Jerzy Cieślik
Andrzej Zorychta
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Abstract

The paper presents the results of assessment studies of the time course for technical wear in masonry buildings located in the area of mining-induced ground deformations. By using fuzzy inference system (FIS) and the “if-then” rule, corresponding language labels describing actual damage recorded in structure components were translated into scalar outputs describing the degree of damage to the building. Adopting this approach made it possible to separate damage resulting from additional effects coming from mining-induced ground deformations and the natural wear and tear of masonry structure. By using statistical analysis an exponential function for the condition of building damage and the function of natural wear and tear were developed. Both phenomena were subject to studies as a function of time regarding the technical age of building structure. The results obtained were used to develop a model for the course of technical wear of traditionally constructed buildings used within mining areas.

In the course of natural wear and tear buildings located in mining areas are additionally exposed to forced ground deformations. The increase of internal forces in structure components induced by those effects results in creating an additional stress factor and damage. The hairline cracks and cracks of building structure components take place when the intensity value of mining effects becomes higher than the component stress resistance and repeated effects result in the decrease of structure rigidity. The observations of building behaviour in mining areas show that the intensity of mining activity and the multiplicity of its effect play a substantial role in the course of technical wear of buildings. The studies show that the level of damage resulting from mining effects adds up to natural wear and tear of the building and impairs the global technical condition as compared to similar buildings used outside mining areas.

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Authors and Affiliations

Izabela Dorota Bryt-Nitarska
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Abstract

Safe mine operations and optimal economical decision making in the context of lignite resources require an adequate level of knowledge about the spatial distribution of critical attributes in terms of geometry and quality in the deposit. Therefore, ore body models are generated using different approaches in geostatistics, depending on the problem to be solved. In this article the analysis of geostatistical methods used for deposits modeling has been presented. Based on exploration data concerning caloric value Q, models of one exemplary lignite deposit has been made. Two models of deposit were prepared using two different methods: ordinary kriging (OK) and sequential Gaussian conditional simulation (SGSIM). Different models of the same deposit were analyzed and compared with source data using criterion of fidelity to statistical attributes like: mean value, variance, statistical distribution. Models, which have been created based on exploration data, were compared with in-situ data gained from survey activities in the exploitation process. As a result of comparison correlation factor and measures of deviations were computed: average relative error, absolute relative error. Models were compared with in situ data, considering statistical features and local variability as well. In conclusion, the study gives valuable information into the benefits of using certain geostatistical approaches for variable tasks and problems in the lignite deposits design process. For the assessment of average values of deposit parameters ordinary kriging provides appropriate effects. Geostatisical simulation (e.g. sequential Gaussian simulation - SGSIM) provides much more relevant information for tasks connected to probability (or risk) of defined threshold exceedences than ordinary kriging. Models made with simulation method are characterized by high fidelity of spatial distribution in comparison to source data.

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Authors and Affiliations

Wojciech Naworyta
Jörg Benndorf
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Abstract

Two kaolin ores with the almost same fineness and purity of original kaolinite but possessing different kaolinite crystallinity (Hinckley Index) were selected to study the influence of crystallinity and calcination conditions on the pozzolanic activity of metakaolin after dehydroxylation. The different calcination conditions were conducted by altering the calcination temperature and holding time to obtain different metakaolin samples with different degrees of dehydroxylation. Then pozzolanic activities of metakaolin samples were tested by the modified Chapelle test, Frattini test and strength evaluations. Additionally, the apparent activation energies of two kaolin ores were calculated to study the thermal properties of kaolinite by isoconversional methods followed by iterative computations. The results showed that pozzolanic activities were dependent on the degree of dehydroxylation, except for the metakaolins calcined at 900℃ due to the fact that recrystallization and high pozzolanic activity was conducted by complete dehydroxylation (degree of dehydroxylation ≥ 90%). Moreover, the lower crystallinity of original kaolinite favored the removal of the structural hydroxyls, leading to a reduction of apparent activation energy and increase of pozzolanic activity, indicating that the higher calcination temperature or longer holding time was required during calcination to reach the same degree of dehydroxylation and finally highly ordered kaolinite converted into the less active metakaolinite, which was confirmed by the lower Ca(OH)2 consumption in the modified Chapelle test, higher [CaO] and [OH] in the Frattini test and weaker compressive strength.
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Bibliography

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4. Bich et al. 2009 – Bich, C., Ambroise, J. and Péra, J. 2009. Influence of degree of dehydroxylation on the pozzolanic activity of metakaolin. Applied Clay Science 44(3), pp. 194–200.
5. Cao et al. 2016 – Cao, Z., Cao, Y., Dong, H., Zhang, J. and Sun, C. 2016. Effect of calcination condition on the microstructure and pozzolanic activity of calcined coal gangue. International Journal of Mineral Processing 146, pp. 23–28.
6. Cyr et al. 2006 – Cyr, M., Lawrence, P. and Ringot, E. 2006. Efficiency of mineral admixtures in mortars: quantification of the physical and chemical effects of fine admixtures in relation with compressive strength. Cement and Concrete Research 36, pp. 264–277.
7. Donatello et al. 2010 – Donatello, S., Freeman-Pask, A., Tyrer, M. and Cheeseman, C.R. 2010. Effect of milling and acid washing on the pozzolanic activity of incinerator sewage sludge ash. Cement and Concrete Composites 32, pp. 54–61.
8. EN 196-1:2005. Methods of Testing Cement. Part 1: Determination of strength.
9. EN 196-5:2005. Methods of Testing Cement. Part 5: Pozzolanicity Test for Pozzolanic Cement.
10. Ferraz et al. 2015 – Ferraz, E., Andrejkovičová, S., Hajjaji, W., Velosa, A.L., Silva, A.S. and Rocha, F. 2015. Pozzolanic activity of metakaolins by the french standard of the modified chapelle test: a direct methodology. Acta Geodynamica et Geomaterialia 179, pp. 289–298.
11. Frías et al. 2000 – Frías, M., Sánchez de Rojas, M.I. and Cabrera, J. 2000. The effect that the pozzolanic reaction of metakaolin has on the heat evolution in metakaolin-cement mortars. Cement and Concrete Research 30, pp. 209–216.
12. Galos, K. 2011. Composition and ceramic properties of ball clays for porcelain stoneware tiles manufacture in Poland. Appled Clay Science 51(1), pp. 74–85.
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Authors and Affiliations

Yuanyuan Liu
1
ORCID: ORCID
Qian Huang
1
Liang Zhao
1
Shaomin Lei
2

  1. Yangtze Normal University, Chongqing Engineering Research Center for Structure Full-Life-Cycle Health Detection and Disaster Prevention, China
  2. Wuhan University of Technology, China
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Abstract

Earth Pressure Balanced shields are currently the most utilized tunnelling machines throughout around the world. The possibility of using conditioning agents that change the mechanical and hydraulic behaviour of a soil, changing it into a plastic paste and thus permitting soil pressure applications at the tunnel face, is the key point to explain the increasing utilization of this technology. Despite its great importance, not much laboratory researches can be registered on soil conditioning, particularly for cohesionless soils. The conditioning criterion is usually defined on the basis of a trial-and-error procedure developed directly at the job sites. A test that is able to simulate the extraction of soil from the bulk chamber with the screw conveyor inclined upwards, as in real machines, can offer a quantitative indication of the conditioned soil behavior for EPB use. The characteristics of the device and the results obtained on many different types of soil are discussed in order to point out the great importance and quality of results that can be achieved using the proposed test device.

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Authors and Affiliations

Luca Borio
Daniele Peila
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Abstract

Native sulphur deposits mined using the underground melting method are characterized by a complex structure, which is the result of the many geologic processes which led to their formation.
The resource utilization rate and the consumption of hot water per ton of sulphur are the main criteria of mining effectiveness. They depend on the porosity and permeability of the rocks forming the deposit, the content and mode of occurrence of sulphur (ore texture), and the distribution of rocks with these varying features. Good recognition of geological and hydrogeological deposit features, exploitation results, is important for formulating the rules of controlling the course of exploitation in order to achieve the best recovery of sulphur with the lowest possible water consumption and to reduce operating costs.
Sulphur deposits are characterized by great local and directional variations in their structure and hydrogeological parameters. This makes the melting process irregular. The flow of hot water and melted sulphur is facilitated in certain directions. As a result, the shape, and distribution and form of exploited parts of the deposit are highly variable. Full information about the deposit is necessary for the proper understanding and prediction of processes that occur in the deposit during sulphur melting, for forecasting its effects, and for controlling the exploitation process. This information is obtained through the lithological description of core samples from exploratory and exploitation boreholes, geophysical borehole logging, and surface seismic surveys.
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Authors and Affiliations

Edyta Sermet
1
ORCID: ORCID
Marek Nieć
2
ORCID: ORCID
Przemysław Bokwa
3

  1. AGH University of Science and Technology, Kraków, Poland
  2. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
  3. KD SA w Sandomierzu, Sandomierz, Poland
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Abstract

Evaluative conditioning (EC) is a change in the evaluation of a neutral stimulus due to its pairing with another affective stimulus. Our Experiment 1 (N = 40) was carried out based on Rydell et al. (2006). During the conditioning stage, participants were presented with pictures of faces (CS) and positive or negative information about their behavior (explicit US). The images were preceded by short verbal primes (implicit US) of opposite valence to behavioral information. In Experiments 2 (N = 122) and 3 (N = 100) we provoked the transfer of implicit and explicit attitudes between USs and CSs by using social objects that potentially carry discrepant implicit and explicit evaluations. The data shows an inconsistency between implicit and explicit attitudes towards The results also confirm that those explicitly assessed attitudes are affected only by explicit information. At the same time, implicit attitudes are influenced not only by automatic processes but also by many other processes and information available to one's conscious mind.
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Authors and Affiliations

Robert Balas
1
ORCID: ORCID
Adriana Rosocha
1

  1. Polish Academy of Sciences, Warsaw, Poland
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Abstract

The research provides a thermodynamic analysis of the theoretical model of a ventilation and air conditioning heat pump system with the ventilation air cold energy recovery depending on outside air parameters, the recovery efficiency and characteristics of a premise. A confectionery production workshop was taken as a prototype where technological conditions (temperature and humidity) must be maintained during the warm season. Calculations using the method of successive approximations to estimate air parameters at system’s nodal points were conducted. It allowed to determine theoretical refrigeration efficiency of the studied system and proved advantages of heat recuperation for smaller energy consumption. The model can be applied for design of heating, ventilation, and air conditioning units which work as a heat pump. The studied system has the highest energy efficiency in the area of relatively low environment temperatures and relative humidity which is suitable for countries with temperate continental climates characterized by low relative humidity.
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Bibliography

[1] Zhang J., Zhang H.-H., He Y.-L., Tao W.-Q.: A comprehensive review on advances and applications of industrial heat pumps based on the practices in China. Appl. Energ. 178(2016), 800–825.
[2] Chwieduk D.: Analysis of utilization of renewable energies as heat sources for heat pumps in building sector. Renew. Energ. 9(1996), 720–723.
[3] Khrustaliov B.M.: Heat Supply and Ventilation. ASV, Moscow 2007 (in Russian).
[4] Mazzeo D.: Solar and wind assisted heat pump to meet the building air conditioning and electric energy demand in the presence of an electric vehicle charging station and battery storage. J. Clean. Prod. 213(2019), 1228–1250.
[5] Chwieduk B., Chwieduk D.: Analysis of operation and energy performance of a heat pump driven by a PV system for space heating of a single family house in Polish conditions. Renew. Energ. 165(2021), 117–126.
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[10] Redko A., Redko O., DiPippo R.: Low-Temperature Energy Systems with Applications of Renewable Energy. Academic Press, Elsevier, 2020.
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[14] State Building Standards of Ukraine DBN B.2.5-67: 2013, “Heating, ventilation and air conditioning”. Ministry of Regional Development, Construction and Housing of Ukraine, Kyiv 2013 (in Ukrainian).
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Authors and Affiliations

Myhailo Kostiantynovych Bezrodny
1
Tymofii Oleksiyovych Misiura
1

  1. National Technical University of Ukraine, Igor Sikorsky, Kyiv Polytechnic Institute, Prosp. Peremohy 37, 03056 Kyiv, Ukraine
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Abstract

This paper reviews theoretical considerations and empirical evidence on the comprehension of counterfactuals. The author sheds light on the issue of fake past and dual meaning. The theories of counterfactuals comprehension are assessed in light of empirical findings. The author supports the view that people hold in mind two meanings of counterfactuals. Based on this account, it is highlighted to differentiate three types of conditionals: suppositional, factual and counterfactual.
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Authors and Affiliations

Ainur Kakimova
1
ORCID: ORCID

  1. Uniwersytet Warszawski
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Abstract

A novel measurement method and a brief discussion of basic characteristics of measuring the phase shift angle between two sinusoidal signals of the same frequency are presented in this paper. It contains a mathematical model for using conditional averaging of a delayed signal interfered with noise to measure the phase shift angle. It also provides characteristics of conditional mean values and discusses the effect of random interferences on the accuracy of the phase shift measurement. The way to determine the variance of the conditional mean value, together with the assessment of standard and expanded uncertainty, are described. The uncertainty characteristic shows the complementary properties of the discussed angle measurement principle �� for small absolute values |��| (minimum for �� = 0) relative to the correlation principle, where the minimum measurement uncertainty is present for �� = ��/2. |
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Authors and Affiliations

Adam Kowalczyk
1
Anna Szlachta
1

  1. Rzeszow University of Technology, Faculty of Electrical and Computer Engineering, Department of Metrology and Diagnostic Systems, W. Pola 2, 35-959 Rzeszow, Poland
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Abstract

Predicting the aging process of residential buildings carried out using traditional technologies is necessary when planning refurbishment works in these buildings. The article presents a picture of the changes in the technical condition of a not refurbished building constructed in traditional technology, in the form of a function describing the aging process according to the PRRD (Prediction of Reliability according to Rayleigh Distribution) model developed by the author. The results of analyses of the relationships between the function of the intensity of damage and the function of unreliability, as well as the function of changes in the performance characteristics of a building which had not undergone refurbishment during the entire course of its use are presented. Three levels of damage intensity during subsequent years of using the building were determined: safe, critical and unacceptable intensity.

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Authors and Affiliations

Beata Nowogońska
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Abstract

The aim of this research was to model the performances of energy and exergy on a Trombe wall system to enable an adequate thermal comfort. The main equations for the heat transfer mechanisms were developed from energy balances on subcomponents of the Trombe wall with the specification of the applicable initial and boundary conditions. During the incorporation of the PCM on the Trombe wall, the micro-encapsulation approach was adopted for better energy conservation and elimination of leakage for several cycling of the PCM. The charging and discharging of the PCM were equally accommodated and incorporated in the simulation program. The results of the study show that an enhanced energy storage could be achieved from solar radiation using PCM-augmented system to achieve thermal comfort in building envelope. In addition, the results correspond with those obtained from comparative studies of concrete-based and fired-brick augmented PCM Trombe wall systems, even though a higher insolation was used in the previous study.
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Bibliography

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Authors and Affiliations

Benjamin O. Ezurike
1
ORCID: ORCID
Stephen A. Ajah
1
ORCID: ORCID
Uchenna Nwokenkwo
1
ORCID: ORCID
Chukwunenye A. Okoronkwo
1
ORCID: ORCID

  1. Department of Mechanical/Mechatronics Engineering, Alex Ekwueme Federal University Ndufu-Alike, Nigeria
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Abstract

The wheel seems to be an invention which – created at the dawn of human civilisation – does not require any changes. Its implicit perfection is a derivative of the definition of the wheel given in mathematics. However, this simplified point of view needs to be confronted with the conditions of land transport, complete with the uneven surfaces hampering the movement of the wheel.
This work presents the subsequent steps, which – during an attempt at a reform of knowledge on land transport – could have led to Józef Hoene-Wroński’s invention of a new type of the wheel. The applied analysis was based on the law of creation developed by the philosopher. The invention is so revolutionary that it still cannot be accepted by constructors of land vehicles.
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Authors and Affiliations

Józef Okulewicz
1
ORCID: ORCID

  1. Politechnika Warszawska (emer.)
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Abstract

In the Accession Treaty of 16 April 2003, Poland agreed to adopt euro as its national currency, but the date of this adoption was not specified. The financial crisis in several countries of the Eurozone, in response to the world financial crisis in 2008, reduced drastically the public support in Poland for the replacement of the zloty by the euro. This article has two objectives. One is to assess the net costs, economic and political, for Poland remaining long outside the Eurozone. In this assessment the analysis includes also two official reports by National Bank of Poland, the country’s central bank, published in 2009 and 2014. The other objective is to note and assess the reforms which have been undertaken by member states of the Eurozone in response to this crisis, in order to maintain and enhance financial stability and economic effectiveness of the rules adopted at the start of the Eurozone on 1 January 1999. The author suggests to consider and adopt additional reforms. Discussed is also the USA experience with its own monetary union, and the potential influence on policy developments in the EU of increasing global competitive pressures from China and India.

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Authors and Affiliations

Stanisław Gomułka

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