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Number of results: 53
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Abstract

Energia elektryczna jest produktem przeznaczonym na sprzedaż. Ma jednak specyficzne znaczenie, które skutkuje nadaniem jej przymiotu dobra publicznego. Przyczyną takiego stanu jest konieczność zagwarantowania ciągłości jej dostaw. Niezbędna jest nie tylko dla prawidłowego funkcjonowania gospodarstw domowych, lecz w szczególności konieczna dla zapewnienia bezpieczeństwa kraju. W obowiązującym systemie gospodarczym, posługując się terminem konstytucyjnym: społeczną gospodarką rynkową, to konkurencja, uważana jest za najlepszą metodę kształtowania rynku i występujących w jego ramach stosunków. Niewątpliwie nie we wszystkich podsektorach energetyki niewidzialna ręka rynku pozwala na realizację swoich celów i funkcji w sposób wystarczający. Zatem niezbędne staje się wprowadzenie odpowiednich, aktywnych mechanizmów regulacji stanowiących skuteczny substytut dla konkurencji. Regulatorowi – czyli prezesowi Urzędu Regulacji Energetyki przypisano szereg zadań i kompetencji. Ma on obowiązek dbania o interes państwa w zakresie rozwoju przedsiębiorstw energetycznych. Równocześnie wykonuje on zadanie ochrony odbiorcy końcowego przed nakładaniem nieuzasadnionych opłat za dostarczaną energię. Jednakże regulator nie może być rzecznikiem wyselekcjonowanej grupy uczestników rynku. Jego funkcją jest zastępowanie mechanizmów konkurencji rynkowej przy wykorzystaniu dostępnych narzędzi prawnych i ekonomicznych. Rolę regulatora należy określić, jako zamiennika rynku konkurencyjnego. Połączenie wskazanych powyżej zadań jest trudne, ale możliwe, przy zachowaniu niezależności regulatora oraz nadaniu i zagwarantowaniu mu uprawnień umożliwiających, m.in. kontrolę nad gospodarką finansową spółek jednoosobowych Skarbu Państwa lub podmiotów państwowych działających w branży dystrybucji energetycznej. Niniejszy tekst ma na celu przedstawienie zależności między rozmaitymi formami aktywności organów regulacyjnych a podmiotami uczestniczącymi w rynku energii, w szczególności spółek zajmujących się dystrybucją energii elektrycznej. Autorzy wskazują, czym jest sama regulacja oraz kto wprowadza normy wiążące strony. Ponadto podejmują staranie przedstawienia czytelnikowi w przystępny sposób zagadnienia przychodu regulowanego oraz uwypuklenia w nim roli regulacji jakościowej. Istotą artykułu jest wykazanie formy i stopnia oddziaływania Regulatora na wyniki finansowe OSD.
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Authors and Affiliations

Michał Andrzej Przybył
Rafał Śpiewak
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Abstract

The text analyses the documentation of the periodic evaluation of academic teachers at 22 Polish universities with the faculties of Pedagogy, shows the conditions of this evaluation and characterises its procedure. The content analysis reveals what issues in the internal regulatory documents establish the periodic evaluation of academic teachers and its procedure, as well as the extent to which they are represented in these documents. In order to fully describe the regulations and to explore the differences among the universities in the area of teacher evaluation, the authors used a statistical analysis. The results show a wide variation of the elements that are included in the internal documents regulating the periodic evaluation of academic teachers. The authors refer to the contemporary press and media discussion on the condition of universities and the directions of their development. They interpret the findings referring also to the contemporary perception of a university as an enterprise as well as to strong bureaucracy at the universities and its adverse impact on their evaluation system.
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Authors and Affiliations

Anna Babicka-Wirkus
Sławomir Pasikowski
Agnieszka Szplit
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Abstract

Polygonum orientale with beautiful red flowers can be found as one dominant species in the vicinity of most water bodies and wetlands in China. However, its phytoremediation potential has not been sufficiently explored because little is known about its resistance to inorganic or organic pollutants. We investigated P. orientale response to low and moderate levels of phenol stress (≤ 80 mg L-1). Endpoints included phenol tolerance of P. orientale and the removal of the pollutant, antioxidant enzyme activities, damage to the cell membrane, osmotic regulators and photosynthetic pigments. In plant leaves, phenol stress significantly increased the activities of peroxidase (POD) and catalase (CAT), as well as the contents of proline, soluble sugars and carotenoids, whereas superoxide dismutase (SOD), H2O2 and electrolyte leakage (EL) levels remained unaltered. On the other hand, there were significant decreases of soluble protein and chlorophyll contents. We demonstrated that, in combination with phenol tolerance and its removal, P. orientale has efficient protection mechanisms against phenol-induced oxidative damage (≤ 80 mg L-1). We propose that P. orientale could be used as an alternative and interesting material in the phytoremediation of phenol.

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Authors and Affiliations

Kai Wang
Jin Cai
Shulian Xie
Jia Feng
Ting Wang
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Abstract

A low drop-out [LDO] voltage regulator with fast transient response which does not require a capacitor for proper operation is proposed in this paper. Recent cap-less LDOs do not use off chip capacitor but instead they use on chip capacitor which occupy a large area on the chip. In the proposed LDO, this on chip capacitor is also avoided. A novel secondary local feedback technique is introduced which helps to achieve a good transient response even in the absence of output capacitor. Further an error amplifier that does need compensation capacitor is selected to reduce the on chip area. Stability analysis shows that the proposed LDO is stable with a phase margin of 78°. The proposed LDO is laid out using Cadence Virtuoso in 180 nm standard CMOS technology. Post layout simulation is carried out and LDO gives 6mV=V and 360µV=mA line and load regulation respectively. An undershoot of 120 mV is observed during the load transition from 0 mA to 50 mA in 1 µs transition time, however LDO is able to recover within 1:4 µs. Since capacitor is not required in any part of design, it occupies only 0:010824 mm2 area on the chip.

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Authors and Affiliations

Guruprasad
Kumara Shama
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Abstract

The article attempts to identify environmental conditions for the development of cogeneration companies in Poland. The article systematizes knowledge about environmental regulations which concern this issue. Within the framework of identified environmental conditions, the authors characterize issues related to national legislation that regulates the operation of cogeneration companies, as well as the requirements resulting from European Union and national regulations in this matter. These regulations, directly and indirectly, affect the long-term future of cogeneration companies and the energy sector as a whole. Undoubtedly, in the current state of environmental regulations in force, the key change for a power company such as a cogeneration company is to meet the requirements for the emission of harmful substances. The change was introduced in 2016 as a result of more stringent emission limits and the adoption of the IED (Industrial Emissions Directive). The implementation of recommendations of the BAT (Best Available Techniques) Conclusions in 2017 additionally tightened the required limits. Undeniably, the key period for cogeneration companies will be 2021 as per the implementation of imposed harmful substances emission’s limits. The article comprehensively discusses the conditions that substantially affect the long-term growth of a cogeneration company and are crucial when making assumptions intended to address strategic development issues in the domestic fuel and power sector.

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Authors and Affiliations

Karol Stós
Jacek Kamiński
Marcin Malec
ORCID: ORCID
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Abstract

The article discusses issues related to improving the energy efficiency of heat supply systems. It draws attention to the need to take action not only for large objects and systems, but also for individual buildings and their boiler plants. Heat supply system monitoring allows for the diagnosis of the weakest elements and making decisions leading to the improvement of energy efficiency. In the case of the boiler room where the research was carried out, the results of such monitoring convinced to equip boilers with an additional automatic control system, with an algorithm limiting the number of burner switching cycles and shutdowns. Limiting the number of switching on the burners, as in the case of other combustion and electric devices, has a significant impact on the energy efficiency of the entire system. In addition, it also increases the durability of the devices, and thus reduces costs of servicing and repairs. The simplest control algorithms, often used in controllers installed in the boiler units, do not provide optimization in this respect. The external device used has allowed the number of burners on and off cycles to be limited while maintaining the quality of the heat supply to the heating installation and the heat treatment system.

The material also presents other ways to improve the energy efficiency of the heat supply system in existing multi-family buildings.

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Authors and Affiliations

Grzegorz Bartnicki
Bogdan Nowak
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Abstract

The study of emotion regulation constitutes a major area of research for having a complete picture of human emotional experience, and several lines of evidence claim that poor emotion regulation skills are particularly deleterious in different aspects of life. Previous tDCS studies have suggested the beneficial role of DLPFC stimulation to improve emotion processing and regulation. The present study was therefore conducted to confirm and extend the effects of DLPFC stimulation on emotion regulation by including both positive and negative emotional material. In this between subjects study, participants were randomly assigned to receive active or sham stimulation over the left DLPFC. Participants viewed negative, positive, and neutral pictures while attempting to decrease, increase, or not modulate their emotional reactions. Subjective reactions were assessed via on-line ratings. The main results show that anodal tDCS stimulation over the left DLPFC slightly improves the ability to increase emotion perception for positive emotions. More interestingly, the results demonstrate that tDCS enhances the regulation of both positive and negative emotions when the baseline is considered. This study provides additional data on the use of tDCS as a tool to increase emotion regulation not only for negative affective material, but also for positive ones.

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Authors and Affiliations

Michel Hansenne
Emilie Weets
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Abstract

The European Water Framework Directive can have enormous consequences for agricul-ture in the Netherlands. In parts of the country agriculture should be taken out of production because the nutrient loads to the surface water system are far too high. This doom scenario is of course unde-sired and a number of source-specific and effect-specific measures are necessary. The fate of nutri-ents in the soil is strongly interrelated with its hydrology. Directly, because nutrients are transported by water and the distribution of the residence time of drainage water is a good measure for the time behaviour of the nutrient loads to the surface water system. Longer residence time in the soil means more of nutrients applied by farmers but also a longer recovery period, after applying source-specific measures. In this paper three promising effect-specific hydrological measures are described buffer strips, retention strips, and controlled drainage.

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Authors and Affiliations

Jan van Bakel
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Abstract

The purpose of the research is to establish the total number of ponds in Ukraine and to analyse the territorial distribu-tion in the administrative areas, as well as in the river basin districts, as the main hydrographic units of water management. Cadastral data of the State Agency of Water Resources of Ukraine regional offices as of 2019 was used in the research (as to Crimea, Donetsk and Luhansk regions we applied the data as of 2014). According the researches there are 50,793 ponds in Ukraine with a total water table area of 2,92899 ha and the volume of 3,969.4 mln m3 of water in 2019. The quantitative distribution of ponds across Ukraine is unequal. Most of them are concentrated in the central part of the country (10.5% of the total number of ponds in the country are in Vinnytsia region). Least of them are in Luhansk region (0.7%). Almost half of the ponds are located in the Dnieper River Basin (48.5%). The lowest quantity of ponds is in the Black Sea Basin (1.2%). The regulation of river basins districts (the rivers of the Sea of Azov, Crimea and Black Sea Basins) reaches 0.71–0.77. As of 2019, 28% of the ponds are rented out. In order to identify the real status of the ponds (both quantitative and qualitative), their recreational role, the environmental impact and the regulation of the hydrographic network in Ukraine, it is necessary to increase the attention to ponds monitoring.

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Authors and Affiliations

Valentyn Khilchevskyi
ORCID: ORCID
Vasyl Grebin
ORCID: ORCID
Myroslava Zabokrytska
ORCID: ORCID
Viktoria Zhovnir
Hanna Bolbot
ORCID: ORCID
Liudmyla Plichko
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Abstract

In the years 1996-2002 evaluation of herbicides' efficacy used in low doses was tested. For investigations several herbicides recommended for weed control in cereals were selected. The results of experiments indicate on possibility of reducing of herbicides' doses by about 25 to 3 7.5%, and still obtaining good effects ofweed control without significant decrease of yielding of cultivation plants. The dose is depended upon sensitivity of weed species, growth stage of weeds and their infestation, density of crop and the weather conditions. Low doses of herbicide can be applied where weeds are in early growth stage, where there is low infestation ofweeds, and weeds show susceptibility to used herbicides, moreover under correct crop density and good weather conditions.
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Authors and Affiliations

Krzysztof Domaradzki
Henryka Rola
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Abstract

In the years 2000-2002 the evaluation of herbicides' efficacy used in lowered doses was conducted. Six herbicides recommended for weed control in spring cereals were used for investigation. The majority of species of weeds occurring in spring wheat and spring barely reacted with a strong (above 90%) decrease of the fresh weight to the treatment with the herbicides applied in the doses reduced by 25%-50% in relation to the recommended ones. Polygonum convolvulus L., Polygonum persicaria L. and Thlaspi arvense L. were very sensitive species as they were very good controlled by tested herbicides in the doses decreased by 50%-75%. Veronica hederifolia L. and Viola arvensis Murr. were characterised by a low level of sensitivity and were controlled only by full recommended doses of tested herbicides. The significant statistical decrease on yield of spring wheat on the objects treated with the herbicides Aurora Super 61,5 SG (mecoprop-P+carfentrazone-ethyl), Granstar 75 DF (tribenuron-methyl) and Grody! 75 WG (amidosulfuron) in the doses lowered by 50% in relation to the recommended ones and Starane 250 EC (fluroxypyr) and Chwastox Trio 540 SL (mecoprop+MCPA+dicamba) in the dose lowered by 50%-7 5% was not observed. In the case of the herbicide Aminopielik D 450 SL (2,4-D+dicamba) the reduction of the dose by 25%-50% also did not cause decrease on yield of spring wheat. In the spring barley, the significant statistical decrease of yielding was not observed on all treatments with tested herbicides applied in the doses reduced by 50%-75%.
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Authors and Affiliations

Krzysztof Domaradzki
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Abstract

This paper presents an analytical approach for solving the weighting matrices selection problem of a linear quadratic regulator (LQR) for the trajectory tracking application of a magnetic levitation system. One of the challenging problems in the design of LQR for tracking applications is the choice of Q and R matrices. Conventionally, the weights of a LQR controller are chosen based on a trial and error approach to determine the optimum state feedback controller gains. However, it is often time consuming and tedious to tune the controller gains via a trial and error method. To address this problem, by utilizing the relation between the algebraic Riccati equation (ARE) and the Lagrangian optimization principle, an analytical methodology for selecting the elements of Q and R matrices has been formulated. The novelty of the methodology is the emphasis on the synthesis of time domain design specifications for the formulation of the cost function of LQR, which directly translates the system requirement into a cost function so that the optimal performance can be obtained via a systematic approach. The efficacy of the proposed methodology is tested on the benchmark Quanser magnetic levitation system and a detailed simulation and experimental results are presented. Experimental results prove that the proposed methodology not only provides a systematic way of selecting the weighting matrices but also significantly improves the tracking performance of the system.
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Authors and Affiliations

Kumar E. Vinodh
Jovitha Jerome
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Abstract

A new simple design methodology which makes LDR output nearly insensitive to jumps of the load current for long times is proposed. This methodology is tested for more than 104 seconds. Our procedure leans on cross coupling of the time second derivative of the LDR power transistor gate and drain voltages along with their currents. This technique keeps low values of these currents in order of nano or hundreds of micro amperes for undershot or overshot cases, respectively. The introduced methodology has been applied to a standard CMOS of 0.18μm technology for NMOS transistors and validated using MATLAB R2014a.

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Authors and Affiliations

Ahmed Abdel_Monem
Mohamed B. El_Mashade
T.E. Dabbous
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Abstract

The aim of the present study was to explore the role of temporal intelligence in English as a Foreign Language (EFL) learners’ self-regulation and self-efficacy. To this end, a general temporal intelligence (GTI-S) scale was designed based on the subconstructs of time in the literature. The scale, along with the learning self-regulation questionnaire (SRQ-L) and the English self-efficacy scale was administered to 520 EFL learners. To validate the GTI-S, confirmatory factor analysis (CFA) was run. The results of Pearson product-moment correlations demonstrated significantly positive relationships between temporal intelligence and controlled self-regulation, automatic self-regulation and self-efficacy (p<.05). Moreover, the findings of multiple regressions revealed that Linearity of Time, Economicity of Time, and Multitasking are the most important subconstructs of time with relation to these variables.

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Authors and Affiliations

Elham Naji Meidani
Reza Pishghadam
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Abstract

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

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Authors and Affiliations

Adnan Daraghmeh
Naji Qatanani
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Abstract

This article is intended to determine the features of public management and the development process of the energy supply system of the Republic of Kazakhstan. Today, the sustainable development of the country’s economy depends directly on the energy sector. Modern society and industry are completely dependent on a stable power supply and today, energy is considered the most important component of the life support of the country’s population. The country’s electrical power industry needs new large-scale investments and promising development. To do this, in the near future, the state needs to consider ways to solve problems that have arisen. The purpose of the study is to consider the elements of public administration and the evolution of the energy supply system in Kazakhstan, as well as public administration systems in other countries, such as the USA, Norway, Great Britain, and the Russian Federation. In the article, with the help of SWOT analysis and scientific analysis, the factors of development of the country’s energy industry are considered.
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Authors and Affiliations

Beimbet Mussin
1
ORCID: ORCID
Zukhra Mussina
2
ORCID: ORCID

  1. Institute of Management, Academy of Public Administration under the President of the Republic of Kazakhstan, Kazakhstan
  2. Almaty Technological University, Kazakhstan
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Abstract

The ventilation system in underground mine is an important guarantee for workers’ safety and environmental conditions. As the mining activities continue, the mine ventilation system is constantly changing. Therefore, to ensure ventilation on demand, the mine ventilation network regulation and optimization are very important. In this paper, the path method based on graph theory is studied. However, the existing path algorithms do not meet the needs of actual mine ventilation regulation and optimization. Therefore, in this paper, the path algorithm is optimized and improved from four aspects. First, based on the depth-first search algorithm, the independent path search algorithm is proposed to solve the problem of false paths in the independent path searched when there is a unidirectional circuit in the ventilation network. Secondly, the independent path calculation formula is amended to ensure that the number of the independent path for the ventilation network with a downcast and an upcast shaft, multi-downcast and multi-upcast shaft and unidirectional circuits is calculated accurately. Thirdly, to avoid both an increase in the number of control points in the multi-fan ventilation network and disturbances in the airflow distribution by determining the reference path through all the independent paths, all the independent paths with the shared fan must be identified. Fourthly, The number and the position of the regulators in the ventilation network are determined and optimized, and the final optimization of air quantity regulation for the ventilation network is realized. The case study shows that this algorithm can effectively and accurately realize the regulation of air quantity of a multi-fan mine ventilation network.
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Authors and Affiliations

Jinmiao Wang
1 2
ORCID: ORCID
Mingtao Jia
1
ORCID: ORCID
Lin Bin
1
ORCID: ORCID
Liguan Wang
1
ORCID: ORCID
Deyun Zhong
1
ORCID: ORCID

  1. School of Resources and Safety Engineering, Central South University, Changsha 410083, China
  2. School of Environment and Resources, Xiangtan University, Xiangtan 411105, China
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Abstract

In this article, we extended the concept of controllability, traditionally used to control the final state of a system, to the exact control of its final speed. Inspired by Kalman’s theory, we have established some conditions to characterize the control that allows the system to reach a desired final speed exactly. When the assumptions ensuring speed-controllability are not met, we adopt a regulation strategy that involves determining the control law to make the system’s final speed approach as closely as possible to the predefined final speed, and this at a lower cost. The theoretical results obtained are illustrated through three examples.
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Authors and Affiliations

Mostafa Rachik
1
ORCID: ORCID
Issam Khaloufi
1
ORCID: ORCID
Youssef Benfatah
1
ORCID: ORCID
Hamza Boutayeb
1
ORCID: ORCID
Hassan Laarabi
1
ORCID: ORCID

  1. Laboratory of Analysis Modeling and Simulation, Department of Mathematics and Computer Science, Faculty of Sciences Ben M’Sik, Hassan II University Casablanca, BP 7955, Sidi Othman, Casablanca, Morocco
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Abstract

Previous studies reported that mental health and emotion regulation strategies deteriorated in the refugee sample. The main goal of the study was to analyze the mediation effect of emotion regulation strategies as expressive suppression and cognitive reappraisal between resilience to helplessness – depression and flourishing. The second aim was to determine to what extent emotion regulation strategies and resilience to helplessness-depression predicted flourishing. Forty-seven Syrian refugees, aged 18-64, who were settled in Istanbul fulfilled the coping competence questionnaire (CCQ), the flourishing scale, and the emotion regulation questionnaire (ERQ). The serial mediation analysis indicated that expressive suppression and cognitive reappraisal had a significant indirect mediating effect between resilience to helplessness-depression and flourishing. Multiple regression analysis showed that expressive suppression was a negative predictor of flourishing. However, both cognitive reappraisal and resilience to helplessness – depression were positive predictors of flourishing. Moreover, ERQ, flourishing, and CCQ scales showed good internal reliability consistency scores in the refugee group. The study suggested that improvement in emotion regulation strategies may be a helpful strategy in the therapeutic setting.
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Authors and Affiliations

Emrullah Ecer
1
ORCID: ORCID

  1. Ural Federal University, Cognitive Neuroscience, MA
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Abstract

The present study aimed to propose a conceptual model of the general effects of the COVID-19 pandemic on the self-regulatory behavior of students learning online. The participants of the study included 350 students of Salman Farsi University of Kazerun who answered an electronic questionnaire from November 5 to November 24, 2020. This electronic questionnaire consisted of two tools: 1. COVID-19 General Impact Survey 2. Online Self-regulated Learning Questionnaire (OSLQ). The results of the structural equation modeling (SEM) showed that the goal orientation dimension has the highest mean (M=17.58) and the time management dimension has the lowest mean (M=10.18) among students. With the increase in negative academic outcomes and the decrease in students' psychological health during the COVID-19, their online self-regulated learning behaviors have also reduced. In addition, the COVID-19 had a negative and direct effect on online self-regulated learning behaviors in students. The results also showed that the greatest effect of the COVID-19 pandemic on the self-regulatory components of online learning was related to the time management component. As for academic achievement, the three dimensions of goal setting, environmental structure, and self- evaluation showed a positive and significant relationship with the average of two semesters of students. Finally, the overall effects of the COVID-19 could explain 11% of online self-regulatory learning behaviors in students. Implicit implications of these findings for education as well as suggestions for further research are discussed.
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Authors and Affiliations

Moslem Abbasi
1
Yaser Khajavi
1
Leila Shameli
1

  1. Salman Farsi University of Kazerun, Iran
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Abstract

Per- and polyfl uoroalkyl substances (PFASs) are human-invented chemicals that were created in the middle of the 20th century. They were synthesized for the fi rst time in 1949, and because of their exceptional surfactant properties, they have been widely used in many industrial applications and daily life products. The common use of PFASs resulted in their worldwide dissemination in natural environment. PFASs are reported to be ubiquitous in surface and drinking waters, but also may be present in soils, animals, milk and milk-products, plants, food. Contaminated drinking water and food are the most signifi cant exposure sources to these chemicals. Ingested PFASs are bio-accumulative and have adverse eff ect on health of humans as well as animal organisms. This paper reviews the most signifi cant information on the origin, properties, distribution, environmental fate, human exposure, health eff ects, and the environmental regulations on PFASs and summarizes the latest advances in the development of novel methods for the eff ective removal of these chemicals from the aqueous environment. Recognized (reverse osmosis, adsorption on activated carbon) and most promising developing removal methods such as adsorption on biomaterials (plant proteins, chitosan beds), mineral adsorbents (LDHs, hydrotalcite), ionexchange resins, and photocatalytic degradation have been emphasized.

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Authors and Affiliations

Mariusz Grabda
1
Sylwia Oleszek
2
Michiaki Matsumoto
3

  1. General Tadeusz Kosciuszko Military University of Land Forces, Wroclaw, Poland
  2. Department of Environmental Engineering, Kyoto University, Kyoto, Japan
  3. Department of Chemical Engineering and Materials Science, Doshisha University, Kyoto, Japan
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Abstract

An application of biostimulants is becoming an increasingly popular operation in agriculture because they positively affect crop performance and qualitative characteristics, and prevent stress-related losses. The objective of this study was to determine the effect of an application of the following biostimulants: PlonoStart, Aminoplant, and Agro-Sorb Folium, and the herbicide Avatar 293 ZC on total carotenoids in table potato tubers. The research material consisted of tubers of two table potato cultivars, Oberon and Malaga, which were produced in a 3-year field experiment. Chemical analyses of fresh material were conducted 4–6 days following harvest. Biostimulants applied with the herbicide significantly increased the table potato tuber content of carotenoids compared to tubers obtained from unamended control plots. The highest accumulation of carotenoids was determined following an application of the biostimulant Agro-Sorb Folium, and it was higher in the tubers of cv. Oberon versus cv. Malaga. It should be added that in the available literature there is no research on the effect of biostimulants on the content of carotenoids in potato, which is the main food in the world. Carotenoids perform many important functions in the human body. They exhibit antioxidant properties, which means that they protect cells from damage, and also have a beneficial effect on the immune system. Carotenoids are substances that show an indispensable effect on the health and appearance of the skin. Regular consumption of them in the form of vegetables and fruits ensures its firmness, elasticity, smoothness, as well as a healthy appearance. The protective function of carotenoids against free radicals simultaneously contributes to slowing down the aging process. This action, in turn, translates into preventing the development of cancer or diseases of the circulatory system.
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Authors and Affiliations

Iwona Mystkowska
1
ORCID: ORCID
Krystyna Zarzecka
2
ORCID: ORCID
Marek Gugała
2
ORCID: ORCID
Agnieszka Ginter
2
ORCID: ORCID

  1. Department of Dieteties, John Paul II University of Applied Sciences, Biała Podlaska, Poland
  2. Department of Agrobioengineering and Animal Sciences, Institute of Agriculture and Horticulture, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland
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Abstract

Due to the fixed rotor magnetic field, the main magnetic flux of conventional permanent magnet synchronous motors (PMSMs) cannot be flexibly adjusted. Recently, the axial-radial flux type permanent magnet synchronous machine (ARFTPMSM) based on the hybrid excitation concept is proposed, which provides a new method for the speed and magnetic field regulations for PMSMs. To analyze the mechanism of magnetic field variation inside the ARFTPMSM, in this paper, three – dimensional finite element models for electromagnetic field calculation of the ARFTPMSM are established. On this basis, the influence of the axial device on the motor is discussed, and the mechanism of flux regulation is explained. By the quantitative calculation of air-gap flux density and the noload back-electromotive force (EMF), the flux regulation capability of the ARFTPMSM is verified. In addition, the effect of the excitation magnetomotive force on the magnetic field harmonics is analyzed combined with the winding theory, and the influence of the axial magneto-motive force (MMF) on the torque fluctuation is obtained. The flux regulation performance of the motor and the validity of the numerical calculation analysis are verified by the experiments.
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Authors and Affiliations

Cunxiang Yang
1
Kun Wang
1
ORCID: ORCID
Ziyang Liu
1
Bin Xiong
2
Qiang Zhao
3

  1. Zhengzhou University of Light Industry, Zhengzhou, Henan, China
  2. Institute of Electrical Engineering of Chinese Academy of Sciences, Beijing, China
  3. Wolong Electric Nanyang Explosion Protection Group Co., LTD.China

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