scholarly journals The Impact of Cutting with a Shearer on the Conditions of Longwall Ventilation

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6907
Author(s):  
Wacław Dziurzyński ◽  
Andrzej Krach ◽  
Teresa Pałka ◽  
Stanisław Wasilewski

In coal mines that are exploiting methane-saturated seams, high-level emission of methane is often the basic limitation for modern and high-efficiency longwall complexes. This paper presents selected observations and tests carried out in the Cw-4 longwall in seam 364/2 of the Budryk mine, which belongs to JSW SA. To observe the methane levels in the Cw-4 longwall, additional sensors were installed at the end section of the longwall from the side of the gobs, and the air velocity and methane concentration were registered in a multi-point system that were built in the selected longwall cross-section. The air parameters were recorded in the monitoring system. The use of multi-point simultaneous measurements of the local velocities and concentrations of methane in the longwall cross-section allowed for the precise determination of the air and methane volume flow using the velocity field method. This allowed us to perform a comparative analysis of the obtained records of the air parameters using special software to determine the distribution of the parameters in the cross-section of the excavation. An important element of the study was the simultaneous registration of the methane concentration in the longwall, information on the operating times, the direction of shearer operation, and the type of work being done (i.e., mining/cleaning).

Author(s):  
Stanisław Wasilewski ◽  
Wacław Dziurzyński ◽  
Teresa Pałka ◽  
Andrzej Krach

The data from the extended system was recorded on-going basis in the archives of the monitoring system, and the multipoint system was directly stored in the methane-anemometers, which allows one to perform a comparative analysis of the obtained records from many methane detectors. An important element of the analyses was the simultaneous registration of the methane concentration in the longwall, together with information on operating time, direction of shearer operation and type of work: mining/cleaning. Mining practice shows that in methane coal mines, methane is often the basic limitation for modern and high-efficiency longwall complexes. The paper reports on selected observations and tests carried out in the Cw-4 longwall in seam 364/2 of the Budryk mine belonging to JSW SA. In observation of the methane level in the Cw-4 longwall, additional sensors installed in the end part of the longwall from the side of the gobs and registration of air velocity and methane concentration in the multipoint system built in the selected longwall cross-section were used, regardless of the air parameters recorded in the monitoring system.


2020 ◽  
pp. 28-34
Author(s):  
N. N. Potekaev ◽  
O. V. Zhukova ◽  
S. I. Artemyeva

Psoriasis is a chronic inflammatory skin disease that is currently viewed as a systemic process due to its association with many comorbid conditions. With the appearance of genetically engineered biological drugs (GEBDs), the treatment of psoriasis has undergone significant changes due to their high efficiency and favorable safety profile. It has been clinically proven that the use of this type of therapy has a positive effect, including on comorbid diseases. However, it must be highlighted that some types of drugs can have a negative effect on the course of these conditions. The characteristics of each individual drug, such as the rate of onset of remission, long-term efficacy, safety profile and effect on comorbidities are different. A better understanding of these characteristics leads to the correct personalized choice of therapy, hence to improved survival of drugs, patient satisfaction and minimization of the impact of psoriasis on the quality of life of patients.This article examines the efficacy and safety of biological drugs in patients with psoriasis, discusses their effect on concomitant diseases pathogenetically associated with psoriasis.To date it is known that the signaling pathway IL-23 / IL-17 plays a key role in the pathogenesis of psoriasis. Promising results are shown by the use of a biological drug aimed at inhibiting IL-23, namely the IL-23 blocker guselkumab. In addition to the high level of therapeutic response in psoriasis, other properties oa the drug have been identified - it has also shown efficacy in patients with concomitant Crohn's disease. Studies describe positive responses in the guselkumab treatment of psoriasis with “difficult” localisations, psoriatic arthritis and Hidradenitis Suppurativa, and its use in patients with cardiovascular risks did not lead to any manifestations of negative dynamics. Thus, further study of the effect of the IL-23 blocker on comorbid pathologies in psoriasis is a promising area. 


2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Keo Oun ◽  
Alexander Topilin

The article is devoted to the history of development, implementation, practice and prospects of development of reinforced concrete prestressing technology in Russia. It is important to expand the scope of application of prestressing technology. As practice shows abroad, it is widely used in road construction. The high level of rigidity and crack resistance of prestressed concrete determines the effectiveness of its use in the construction of highways and runways. Pre-stress, which increases the rigidity and resistance of structures to cracking, increases their endurance when working on the impact of repeated loads. This is due to a decrease in the voltage drop in the reinforcement and concrete, caused by changes in the external load. Properly designed structures and buildings are generally safe to use and more reliable, especially in seismic areas. On the basis of this technology can be made a significant step forward in the field of high-rise construction, where the main problem is due to the fact that the upper floors are extremely loaded lower. In the proposed embodiment, the number of storeys of the building can be doubled without increasing the load on the ground floor and the base. International experience shows high efficiency of the high efficiency of application of the preliminary voltage monolithic slab foundations of long, monolithic beamless slabs, the supporting device and the pedestals under heavy equipment, in load-bearing monolithic constructions of underground structures, including multi-storey. There are examples of pre-stress during the restoration of historical monuments. As practice shows, the prestressing of reinforced concrete demonstrates new opportunities and defines the prospect of development of reinforced concrete as a material for the construction of modern buildings and structures.


Economies ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 113
Author(s):  
My-Linh Thi Nguyen ◽  
Toan Ngoc Bui

This paper focuses on examining the nonlinear impact of trade openness (TO) on economic growth (EG) in the Asean-6 countries (Indonesia, Malaysia, Thailand, Singapore, Philippines, and Vietnam). In order to achieve the set research objectives, the authors estimate the research model through the fixed-effect panel threshold approach. Unlike previous studies, this paper finds that there is a nonlinear impact of TO on EG, whereby TO has two threshold values. Specifically, before the first threshold value, TO plays an important role in boosting EG. However, this impact level decreases gradually when TO exceeds this threshold value. In particular, when exceeding the second threshold value, the impact of TO on EG is still positive but has a relatively low value. The research results show that if TO increases to a high level (beyond the threshold value) without combining with other complementary policies, this does not encourage high-efficiency EG. In addition, this study also shows that EG is positively affected by domestic investment and negatively affected by financial crisis. The findings in this paper are of great importance for the Asean-6 countries as well as researchers.


2020 ◽  
Vol 91 (3) ◽  
pp. 31301
Author(s):  
Nabil Chakhchaoui ◽  
Rida Farhan ◽  
Meriem Boutaldat ◽  
Marwane Rouway ◽  
Adil Eddiai ◽  
...  

Novel textiles have received a lot of attention from researchers in the last decade due to some of their unique features. The introduction of intelligent materials into textile structures offers an opportunity to develop multifunctional textiles, such as sensing, reacting, conducting electricity and performing energy conversion operations. In this research work nanocomposite-based highly piezoelectric and electroactive β-phase new textile has been developed using the pad-dry-cure method. The deposition of poly (vinylidene fluoride) (PVDF) − carbon nanofillers (CNF) − tetraethyl orthosilicate (TEOS), Si(OCH2CH3)4 was acquired on a treated textile substrate using coating technique followed by evaporation to transform the passive (non-functional) textile into a dynamic textile with an enhanced piezoelectric β-phase. The aim of the study is the investigation of the impact the coating of textile via piezoelectric nanocomposites based PVDF-CNF (by optimizing piezoelectric crystalline phase). The chemical composition of CT/PVDF-CNC-TEOS textile was detected by qualitative elemental analysis (SEM/EDX). The added of 0.5% of CNF during the process provides material textiles with a piezoelectric β-phase of up to 50% has been measured by FTIR experiments. These results indicated that CNF has high efficiency in transforming the phase α introduced in the unloaded PVDF, to the β-phase in the case of nanocomposites. Consequently, this fabricated new textile exhibits glorious piezoelectric β-phase even with relatively low coating content of PVDF-CNF-TEOS. The study demonstrates that the pad-dry-cure method can potentially be used for the development of piezoelectric nanocomposite-coated wearable new textiles for sensors and energy harvesting applications. We believe that our study may inspire the research area for future advanced applications.


Author(s):  
V. Kovpak ◽  
N. Trotsenko

<div><p><em>The article analyzes the peculiarities of the format of native advertising in the media space, its pragmatic potential (in particular, on the example of native content in the social network Facebook by the brand of the journalism department of ZNU), highlights the types and trends of native advertising. The following research methods were used to achieve the purpose of intelligence: descriptive (content content, including various examples), comparative (content presentation options) and typological (types, trends of native advertising, in particular, cross-media as an opportunity to submit content in different formats (video, audio, photos, text, infographics, etc.)), content analysis method using Internet services (using Popsters service). And the native code for analytics was the page of the journalism department of Zaporizhzhya National University on the social network Facebook. After all, the brand of the journalism department of Zaporozhye National University in 2019 celebrates its 15th anniversary. The brand vector is its value component and professional training with balanced distribution of theoretical and practical blocks (seven practices), student-centered (democratic interaction and high-level teacher-student dialogue) and integration into Ukrainian and world educational process (participation in grant programs).</em></p></div><p><em>And advertising on social networks is also a kind of native content, which does not appear in special blocks, and is organically inscribed on one page or another and unobtrusively offers, just remembering the product as if «to the word». Popsters service functionality, which evaluates an account (or linked accounts of one person) for 35 parameters, but the main three areas: reach or influence, or how many users evaluate, comment on the recording; true reach – the number of people affected; network score – an assessment of the audience’s response to the impact, or how far the network information diverges (how many share information on this page).</em></p><p><strong><em>Key words:</em></strong><em> nativeness, native advertising, branded content, special project, communication strategy.</em></p>


2020 ◽  
Vol 2020 (10) ◽  
pp. 19-33
Author(s):  
Nadiia NOVYTSKA ◽  
◽  
Inna KHLIEBNIKOVA ◽  

The market of tobacco products in Ukraine is one of the most dynamic and competitive. It develops under the influence of certain factors that cause structural changes, therefore, the aim of the article is to conduct a comprehensive analysis of transformation processes in the market of tobacco and their alternatives in Ukraine and identify the factors that cause them. The high level of tax burden and the proliferation of alternative products with a potentially lower risk to human health, including heating tobacco products and e-cigarettes, are key factors in the market’s transformation process. Their presence leads to an increase in illicit turnover of tobacco products, which accounts for 6.37% of the market, and the gradual replacement of cigarettes with alternative products, which account for 12.95%. The presence on the market of products that are not taxed or taxed at lower rates is one of the reasons for the reduction of excise duty revenues. According to the results of 2019, the planned indicators of revenues were not met by 23.5%. Other reasons for non-fulfillment of excise duty revenues include: declining dynamics of the tobacco products market; reduction in the number of smokers; reorientation of «cheap whites» cigarette flows from Ukraine to neighboring countries; tax avoidance. Prospects for further research are identified, namely the need to develop measures for state regulation and optimization of excise duty taxation of tobacco products and their alternatives, taking into account the risks to public health and increasing demand of illegal products.


2020 ◽  
Vol 38 (3) ◽  
Author(s):  
Shoaib Ali ◽  
Imran Yousaf ◽  
Muhammad Naveed

This paper aims to examine the impact of external credit ratings on the financial decisions of the firms in Pakistan.  This study uses the annual data of 70 non-financial firms for the period 2012-2018. It uses ordinary least square (OLS) to estimate the impact of credit rating on capital structure. The results show that rated firm has a high level of leverage. Moreover, Profitability and tanagability are also found to be a significantly negative determinant of the capital structure, whereas, size of the firm has a significant positive relationship with the capital structure of the firm.  Besides, there exists a non-linear relationship between the credit rating and the capital structure. The rated firms have higher leverage as compared to the non-rated firms. The high and low rated firms have a low level of leverage, while mid rated firms have a higher leverage ratio. The finding of the study have practical implications for the manager; they can have easier access to the financial market by just having a credit rating no matter high or low. Policymakers must stress upon the rating agencies to keep improving themselves as their rating severs as the measure to judge the creditworthiness of the firm by both the investors and management as well.


2019 ◽  
Vol 72 (5) ◽  
pp. 779-783
Author(s):  
Victor A. Ognev ◽  
Anna A. Podpriadova ◽  
Anna V. Lisova

Introduction:The high level of morbidity and mortality from cardiovascular disease is largely due toinsufficient influence on the main risk factors that contribute to the development of myocardial infarction.Therefore, a detailed study and assessment of risk factors is among the most important problems of medical and social importance. The aim: To study and evaluate the impact of biological, social and hygienic, social and economic, psychological, natural and climatic risk factors on the development of myocardial infarction. Materials and methods: A sociological survey was conducted in 500 people aged 34 to 85. They were divided into two groups. The main group consisted of 310 patients with myocardial infarction. The control group consisted of 190 practically healthy people, identical by age, gender and other parameters, without diseases of the cardiovascular system. Results: It was defined that 30 factors have a significant impact on the development of myocardial infarction.Data analysis revealed that the leading risk factors for myocardial infarction were biological and socio-hygienic. The main biological factors were: hypertension and hypercholesterolemia. The man socio-hygienic factor was smoking. Conclusions: Identification of risk factors provides new opportunities for the development of more effective approaches for the prevention and treatment of myocardial infarction.


2021 ◽  
Vol 22 (9) ◽  
pp. 4961
Author(s):  
Maria Kovalska ◽  
Eva Baranovicova ◽  
Dagmar Kalenska ◽  
Anna Tomascova ◽  
Marian Adamkov ◽  
...  

L-methionine, an essential amino acid, plays a critical role in cell physiology. High intake and/or dysregulation in methionine (Met) metabolism results in accumulation of its intermediate(s) or breakdown products in plasma, including homocysteine (Hcy). High level of Hcy in plasma, hyperhomocysteinemia (hHcy), is considered to be an independent risk factor for cerebrovascular diseases, stroke and dementias. To evoke a mild hHcy in adult male Wistar rats we used an enriched Met diet at a dose of 2 g/kg of animal weight/day in duration of 4 weeks. The study contributes to the exploration of the impact of Met enriched diet inducing mild hHcy on nervous tissue by detecting the histo-morphological, metabolomic and behavioural alterations. We found an altered plasma metabolomic profile, modified spatial and learning memory acquisition as well as remarkable histo-morphological changes such as a decrease in neurons’ vitality, alterations in the morphology of neurons in the selective vulnerable hippocampal CA 1 area of animals treated with Met enriched diet. Results of these approaches suggest that the mild hHcy alters plasma metabolome and behavioural and histo-morphological patterns in rats, likely due to the potential Met induced changes in “methylation index” of hippocampal brain area, which eventually aggravates the noxious effect of high methionine intake.


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