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This paper provides a real application of a popular swarm-intelligence optimisation method. The aim is to analyse the efficiency of various settings of the marine predator algorithm (MPA). Four crucial numerical parameters of the MPA are statistically analysed to propose the most efficient setting for solving engineering problems. Besides population size, particle velocity parameter P, Lévy flight parameter β , and fish aggregating device (FAD) probabilities are studied. Finally, 193 various settings, including fixed values and dynamic changes of the MPA parameters, are experimentally compared when solving 13 engineering problems. Standard statistical approaches are employed to highlight significant differences in various MPA settings. The setting of two MPA parameters (P, FADs) significantly influences MPA performance. Three newly proposed MPA settings outperform the original variant significantly. The best results provide the MPA variant with the dynamic linear change of P from 0.5 to 0. These parameters influence the velocity of prey and predator individuals in all three stages of the MPA search process. Decreasing the value of P showed that decreasing the velocity of individuals during the search provides good performance. Further, lower efficiency of the MPA with higher FAD values was detected. It means that more occasional use of fish aggregating devices (FADs) can increase the solvability of engineering problems. Regarding population size, lower values ( N = 10 ) provided significantly better results compared with the higher values ( N = 500 ). [ABSTRACT FROM AUTHOR]

Abstract: In this paper the results of testing thermal parameters of the rock environment and measurement of borehole temperature profiles of the newly constructed experimental underground heat storage (BTES (Borehole Thermal Energy Storage)) in Paskov (Czech Republic) obtained with the TRT (thermal response method) and temperature measurement on boreholes at selected depth levels are summarised. The TRT measurement series on eight boreholes has shown the possibility to compare the differences among individual measurements in a practically identical rock environment. The temperature profiling of boreholes enabled studying the dynamics of temperature changes occurring in the rock environment as a reaction to the heat supply during the TRT. The measurement series was performed with the aim to assess the possibility of shortening the TRT duration while maintaining the acceptable precision of the measured results. For this reason the software simulation of shortening the TRT duration to 24 h was performed, and the influence of such shortening to the precision of determination of values and was studied. The simulation has shown that shortening the test to 24 h in our case would have brought an acceptable amount of inaccuracy with regard to the dispersion of measured values obtained from the real test. [Copyright &y& Elsevier]

Abstract: Significant part of CO2 emissions from industrial sources in Central Europe originates from the territory of the Upper Silesian Coal Basin (USCB). This paper presents a study of the suitability of saline aquifers within the USCB, as potential greenhouse gas repositories. Evaluation of mineral-trapping mechanisms and assessment of storage capacity of the aquifers is based on hydrochemical modeling and experimental tests of rock–water–gas interactions. Two stages of modeling enabled prediction of the immediate changes in the aquifer and insulating rocks impacted by the beginning of CO2 injection, and the assessment of long-term effects of sequestration. In the analyzed sandstone aquifers the minerals able to trap CO2 are dawsonite and dolomite, while siderite or calcite are able to degrade. The phases capable of mineral CO2 trapping in the cap rocks are: dawsonite, dolomite, and siderite. Mineral-trapping capacity, for the sandstone aquifers is relatively low: 1.2 to 1.9 kgCO2/m3, with the exception of the Upper Silesian Sandstone Series – over 6.6 kgCO2/m3. The solubility trapping capacity does not exceed 4.07 kgCO2/m3. [Copyright &y& Elsevier]

This paper proposes the real-world application of the Differential Evolution (DE) algorithm using, distance-based mutation-selection, population size adaptation, and an archive for solutions (DEDMNA). This simple framework uses three widely-used mutation types with the application of binomial crossover. For each solution, the most proper position prior to evaluation is selected using the Euclidean distances of three newly generated positions. Moreover, an efficient linear population-size reduction mechanism is employed. Furthermore, an archive of older efficient solutions is used. The DEDMNA algorithm is applied to three real-life engineering problems and 13 constrained problems. Seven well-known state-of-the-art DE algorithms are used to compare the efficiency of DEDMNA. The performance of DEDMNA and other algorithms are comparatively assessed using statistical methods. The results obtained show that DEDMNA is a very comparable optimiser compared to the best performing DE variants. The simple idea of measuring the distance of the mutant solutions increases the performance of DE significantly. [ABSTRACT FROM AUTHOR]

Thermal performance of building materials is an important parameter from the point of view of energy consumption for heating buildings, which is obviously related to environmental protection standards. Thermal parameters of roofing slates were measured for samples from two different formations in the Czech Republic. These were rocks of lower Carboniferous Culm facies of Moravice Formation and Silesian Unit of Flysch Moravian-Silesian Carpathians. Thermal conductivity and thermal effusivity measurements were performed with use of TCi analyser. Thermal parameters were obtained in parallel and perpendicular direction to the bedding in rocks. Thermal conductivity of the Moravian slates in the direction perpendicular to the bedding ranges from 1.43 to 1.79 W m−1 K−1, while for samples from Carpathian region this parameter ranges from 1.99 to 3.15 W m−1 K−1. High values of thermal conductivity correlate to higher quartz content in the rocks. The measured thermal parameters (conductivity, effusivity, diffusivity) are strongly depending on the direction of measurement. Thermal conductivity of analysed rocks increases along with increase in temperature. The increase in thermal conductivity value is more significant in case of Moravian slates. In practice, the obtained results indicate that the traditional building material, such as roofing slates, shows better insulation properties at lower temperatures, while in conditions of strong sunlight the temperature conductivity increases. In case of roofing slates, which tend to be highly anisotropic, the essential information is the direction of thermal parameters measurement. Slates, due to their specific texture, are characterized by a very high thermal anisotropy coefficient. [ABSTRACT FROM AUTHOR]

This paper presents a research on students using the Gazepoint device to visualise the practices and strategies that students used in order to solve assignments in the disciplines of natural science. The analysis of visual perception of students is complemented by a questionnaire survey for a group of respondents aged 15-16. The essence of the study was to find out how the students proceeded in monitoring assignments displayed on the screen, how they continued working with the assignments, and whether the layout of the schematics, tables and applied images affected students 'correctness for the solution. The main aim of the research was to find some similar segments in the experimental data and obtained clusters that would suggest a similar approach of problem solving by students - respondents, and to find out if, and possibly how, some strategies in the assignments differ for the talented students from the standard pupil population and compare the outcomes with students' characteristics. The other aim of study was to confirm the presence of gifted students in natural sciences in a given sample of respondents on the basis of eye-tracking technology. Also on the basis of similarities in assigned task solving the aim was to find other students who can be seen similarly to the gifted ones from a view of e.g. physiological dynamics of eyes of the students in the context of the given selected seven tasks in the area of the chemical elements identification. For both groups of students, some basic measures are proposed to increase the efficiency of students' work with an assignment displayed on a computer screen. Our results show that in the task solving, one gifted student was identified next to a cluster of four similarly performing students on the basis of eye-movements parameters. [ABSTRACT FROM AUTHOR]

The aim of the study was to examine the possibility of determining the pore space in microporous rocks using a set of methods: differential thermal analysis, retort distillation, and Dean-Stark. These methods are used for low-permeability rock containing hydrocarbons, such as shale gas, shale oil and tight gas. By using these methods it is possible to specify the amount of water contained in the sample and, consequently, determine the different levels of saturation and porosity. The study showed shale porosity values ranging from 0% to more than 5%. It was found that the samples with the highest porosities in the combustion process evolve relatively large amounts of carbon dioxide, which indicate that the porosity is related to the presence of organic matter. There was no complete correlation between the various methods׳ test results. It seems that for determining the porosity of tight shale rocks, the most effective would be the use of several complementary methods. [ABSTRACT FROM AUTHOR]

The paper introduces a new approach to enhance optimization algorithms when solving the piecewise linearization problem of a given function. Eight swarm intelligence algorithms were selected to be experimentally compared. The problem is represented by the calculation of the distance between the original function and the estimation from the piecewise linear function. Here, the piecewise linearization of 2D functions is studied. Each of the employed swarm intelligence algorithms is enhanced by a newly proposed automatic detection of the number of piecewise linear parts that determine the discretization points to calculate the distance between the original and piecewise linear function. The original algorithms and their enhanced variants are compared on several examples of piecewise linearization problems. The results show that the enhanced approach performs sufficiently better when it creates a very promising approximation of functions. Moreover, the degree of precision is slightly decreased by the focus on the speed of the optimization process. [ABSTRACT FROM AUTHOR]

Thermal methods (simultaneous thermal analysis coupled with quadrupole mass spectrometry STA- QMS and retort) were applied to characterization of microporous rocks of different clay content. Two series of samples were investigated: highly diagenetic lower Paleozoic mudstones from Polish Lowlands and less altered Miocene and Paleocene rocks from the Carpathian Foredeep. The aim of the presented work was to differentiate between "free" and "bound" water in the pore space, to estimate the amount of fluids obtained by using retort method in regard to the distinction between free water, capillary water, clay bound water and organic matter fluids. In order to evaluate the retort results it was necessary to determine the temperatures at which a particular kind of water is released. The interpretation was based on the results of STA – QMS investigations together with XRD analysis of the mineral content, cation exchange capacity (CEC) and organic carbon content (TOC) measurements. In STA investigations the loss of mass connected with water release from clay minerals was observed in two temperature ranges: from 40 °C to 150 °C (adsorbed water) and from 440 °C to 620 °C (structural water). When analysing retort measurements, a considerable upward shift of adsorbed water release temperature can be observed. In case of Miocene and Paleocene rocks interpretation results of adsorbed water content indicate the temperature range from 150 to 450 °C, and in case of Lower Paleozoic rocks from 150 °C to 350 °C. Structural water is released at temperatures 500 °C −650 °C. A condensate connected with organic matter was observed within the temperature range 350–500 °C for Lower Paleozoic rock samples of high organic matter content (TOC>2). Taking into account the methodical discrepancies, a satisfactory compliance of results obtained by both methods in regard to the volume of clay bound water and condensate connected with organic matter was found. The results show that thermal methods can be successfully used for evaluation of saturations necessary for proper estimation of reservoir properties. • Differentiation between free and bound water by simultaneous use of STA and Retort methods. • Average content of clay bound water in early diagenetic Miocene mudstones amounts to 3,4% volume. • In Paleozoic mudstones the average content of clay bound water amounts to: 0,7% volume. [ABSTRACT FROM AUTHOR]