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Abstract

Theoretical and experimental research indicates that radial loads have a significant influence on the value of belt-on-idler rolling resistances. Computational models discussed in literature use the notion of unit rolling resistance, i.e. rolling resistance per unit length of the idler. The total value of the rolling resistance of belt on a single idler is determined by integrating unit rolling resistance with respect to the length of the contact zone between the belt and the idler. This procedure requires the knowledge of normal load distribution along the contact zone between the belt and the idler. Loads acting on the idler set have been the object of both theoretical analyses and laboratory tests. Literature mentions several models which describe the distribution of normal loads along the contact zone between the belt and the idler set (Krause & Hettler, 1974; Lodewijks, 1996; Gładysiewicz, 2003; Jennings, 2014). Numerous experimental tests (Gładysiewicz & Kisielewski, 2017; Król, 2017; Król & Zombroń, 2012) demonstrated that the resultant normal loads acting on idlers are approximate to the loads calculated in theoretical models. If the resultant normal load is known, it is possible to assume the distribution of loads acting along the contact zone between the belt and the idler. This paper analyzes various hypothetical load distributions calculated for both the center idler roll and for the side idler roll. It also presents the results of calculations of belt rolling resistances for the analyzed distributions. In addition, it presents the results of calculations with allowance for load distribution along the generating line of the idler.

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Authors and Affiliations

Lech Gładysiewicz
Martyna Konieczna-Fuławka
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Abstract

Noise measurements have been carried out at eleven different sites located in three prominent cities of the Tarai region of India to evaluate the effectiveness of vegetation belts in reducing traffic noise along the roadsides. Attenuation per doubling of distance has been computed for each site and excess attenuation at different 1/3 octave frequencies has been estimated. The average excess attenuation is found to be approximately 15 dB over the low frequencies (200 Hz to 500 Hz) and between 15 dB to 20 dB over the high frequencies (8 kHz to 12.5 kHz). Over the critical middle frequencies (1-4 kHz), the average excess attenuation (between 10-15 dB) though not as high, is still significant, with a number of sites showing an excess attenuation of 15 dB or more at 1 kHz. The results indicate that sufficiently dense vegetation belts along the roadsides may prove as effective noise barriers and significant attenuation may be achieved over the critical middle frequencies (1-4 kHz).
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Authors and Affiliations

Vikrant Tyagi
Krishan Kumar
V.K. Jain
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Abstract

The paper presents a model for dynamic analysis of belt transmission. A two dimensional discrete model was assumed of a belt consisting of rigid bodies joined by translational and torsion spring-damping elements. In the model, both a contact model and a dry friction model including creep were taken into consideration for belt-pulley interaction. A model with stiffness and damping between the contacting surfaces was used to describe the contact phenomenon, whereas a simplified model of friction was assumed. Motion of the transmission is triggered under the influence of torque loads applied on the pulleys. Equations of motion of separate elements of the belt and pulleys were solved numerically by using adaptive stepsize integration methods. Calculation results are presented of the reaction forces acting on the belt as well as contact and friction forces between the belt body and pulley in the sample of the belt transmission. These were obtained under the influence of the assumed drive and resistance torques.

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Authors and Affiliations

Krzysztof Kubas
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Abstract

Reconciliation between two copper ore mines transferred ore from one mine to another for processing in enrichment plants generated the need to regularly study the amount and composition of the ore on the conveyor connecting these two mines. To ensure the objectivity of the study, taking composite samples and their analysis was entrusted to a specialized outside laboratory. However, the managing staff of both mines still have doubts whether sampling results reflect correctly content of transported ore especially when the fed is highly variable. In order to investigate how the relatively low sampling rate affects the accuracy and precision of the measurement, the article investigates the hypothetical situation on the linking conveyor with the ore having extremely differentiated mineralization: 80% of almost barren rock (below 0.7% Cu) and 20% of the richly mineralized shale (around 10% Cu). Such ore occurs in some areas of the mine, from which it is fed onto a connecting conveyor. Through simulation techniques it was examined how the frequency of sampling can influence the distribution of the pooled sample results. It turned out that for 16 randomly selected samples in the following 15 minutes time intervals of a working shift, the spread of results around the simulated value is very large. A satisfactory accuracy level for the estimations of mean Cu content in the transported ore is achieved when the samples are collected at 30-second intervals. Only with sampling frequency close to on-line scanner parameters the probability of obtaining estimations with deviation exceeding 10% drops to the level of 2%. In the case of extremely differentiated ore doubts about confidence in the described measurements are fully confirmed, because with over 50% probability a single measurement could be deviated by 50% up and down from the true value.

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Authors and Affiliations

Leszek Jurdziak
Witold Kawalec
Robert Król
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Abstract

In the paper, the authors present the solution aimed at increasing reliability of the conveyor units. The analysis of technological and operational defects of conveyor rollers is presented. The changes in manufacturing technology have been proposed, which allowed for avoiding welding and provided the required level of tightness.

Computer simulation of the motion of air in the labyrinth seal of the roller was conducted to determine the numerical parameters of possible airflows. It is proved that the airflow is present in the gap of the labyrinth seal due to the roller rotation. It is shown that the reason for the penetration of abrasive particles through the labyrinth seal after stopping is decompression, which occurred as a result of temperature change and push out of airflows during rotation. It is also suggested that the number of stops during the operation should be taken into account when determining the durability of rollers. Practical recommendations are given for preventing the penetration of abrasive particles during conveyor stops and the need for combined seals. The results can be used for the construction of roller conveyor belts in any industry.

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Bibliography

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[12] V.V. Gusev et al. Application of modern materials in end seals of mining equipment. Science and Technology to Production, 2:84, 2004. (in Russian).
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Authors and Affiliations

G. Kononov
1
S. Artemov
1
S. Dubrovskyi
2
Dariya Kravtsova
2

  1. Ferrum-Stroy-Servise, Schastye, Lugansk region, Ukraine.
  2. Kryvyi Rih National University, Kryvyi Rih, Ukraine.
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Abstract

Artificial water reservoirs pose impact on the natural environment. Impact of the artificial Czorsztyn Lake on groundwater and land management is assessed. The study is based on long-term observations of chemistry, groundwater levels and spring discharges during reservoir construction, filling, and 25-year-long exploitation. Land management changes caused by reservoir construction were recognized using remote sensing. Reservoir construction resulted in land management change in the study area. Built-up and forest areas gained prevalence over farmland areas. Two types of groundwater dominate: HCO3–Ca and HCO3–Ca–Mg, both before reservoir filling (68% analyses) and afterwards (95% analyses), and in control analyses from September 2020 (100% analyses). Gradual decrease in the occurrence of water types with the sulphate ion exceeding 20% mvals is documented, which points to water quality improvement trends. Moreover, changes of water saturation index values with regard to aquifer-forming mineral phases during reservoir construction and early exploitation phasei ndicate hydrochemical modifications. Decrease of groundwater level was related with transformation of the Dunajec river valley during reservoir construction and, accordingly, decrease of regional drainage base level. Groundwater level increased after reservoir filling, which points to coupled impact of the reservoir and increased precipitation recharge. Construction of the Czorsztyn Lake resulted in gradual land management transformation from farmlands into tourist-recreational areas. This change and river valley flooding by surface waters did not cause significant modifications in groundwater quantity and quality. Organization of water-sewage management related with reservoir construction resulted in noticeably improved quality trends.
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Bibliography

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Authors and Affiliations

Włodzimierz Humnicki
1
ORCID: ORCID
Ewa Krogulec
1
Jerzy Małecki
1
ORCID: ORCID
Marzena Szostakiewicz-Hołownia
1
ORCID: ORCID
Anna Wojdalska
1
Daniel Zaszewski
1
ORCID: ORCID

  1. Faculty of Geology, University of Warsaw, Poland
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Abstract

This paper is a summary of the results of research on the accumulation conditions of the Upper Younger Loess (LMg) in Poland and Bug loess (bg) in Ukraine from the maximum stage (MIS 2) of the Vistulian (Weichselian) Glaciation in central and eastern Europe. These studies included an analysis of the morphological (topographic) situation of the loess cover, its grain size and heavy mineral composition, the preserved structures of loess sedimentation as well as mollusc and pollen analyses of this loess. They revealed that the accumulation of Upper Younger Loess (UYL) might have been more dependent on the prevailing moisture conditions than previously thought. These conditions could have been caused by cold air masses from an ice sheet and warm air masses from the Mediterranean Sea and Atlantic coming together in the Carpathians and the Holy Cross Mountains and favouring the formation of dust storms and precipitation. In this process, a loading of loess dust (formed from local rocks weathering in periglacial conditions) by atmospheric moisture particles was especially significant. The moist substrate not only favoured the periodic development of vegetation and molluscs but also enabled the interception of dust and the accumulation of an increasingly thick loess cover. Westerly and south-westerly winds predominated in the UYL as indicated by the topographic position of loess patches and the mineral composition of the studied loess. Periodically an increased air circulation from the east and northeast occurred.
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Authors and Affiliations

Jan Dzierżek
1
Leszek Lindner
1
Roman Chlebowski
1
Marcin Szymanek
1
Andryi Bogucki
2 3
Olena Tomeniuk
2 3

  1. University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, 02-089 Warszawa, Poland
  2. Ivan Franko National University of Lviv, Department of Geomorphology and Palaeogeography, Doroshenka 41, 79000 Lviv, Ukraine
  3. National Academy of Sciences of Ukraine, I. Krypiakevych Institute of Ukrainian Studies, Vynnychenka 24, 79008 Lviv, Ukraine
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Abstract

The Northern Copper Belt is located in south-western Poland, a region well known for its copper and silver occurrences of varying significance. This area also includes the abandoned mines of the North-Sudetic Trough (Old Copper District), as well as the currently active New Copper District in the southern part of the Fore- Sudetic Monocline. The vast exploration programme of Miedzi Copper Corp. initiated in 2011 in the northern, deeper part of the Fore Sudetic Monocline provided new data about the deeper parts of this geological unit, located north of the known deposits. A number of prospective areas with Cu-Ag mineralization were investigated, which ultimately resulted in the discovery of three new Cu-Ag deposits. Both the prospective areas and the documented deposits form the so-called Northern Copper Belt, which as a whole has high potential for the identification of new ore deposits and an increase in resources. A description of these three new deposits is provided along with characteristics of the areas of their possible extension, and the additional prospective areas with hypothetical and speculative resources. The new deposits are compared to other Polish Cu-Ag ore deposits, with an emphasis on differences in their geological structure and mineralogy. The paper also presents a brief summary of the applied new exploration tools which have led to this discovery.
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Authors and Affiliations

Stanisław Speczik
1
ORCID: ORCID
Krzysztof Szamałek
1
ORCID: ORCID
Jan Wierchowiec
1
Krzysztof Zieliński
2
ORCID: ORCID
Alicja Pietrzela
1
ORCID: ORCID
Tomasz Bieńko
1
ORCID: ORCID

  1. University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, 02-089 Warszawa, Poland
  2. Miedzi Copper Corp., Al. Jerozolimskie 96, 00-807 Warszawa, Poland
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Abstract

Industrial applications require functional surfaces with a strictly defined micro-texture. Therefore engineered surfaces need to undergo a wide range of finishing processes. One of them is the belt grinding process, which changes the surface topography on a range of roughness and micro-roughness scales. The article describes the use of machined surface images in the monitoring process of micro-smoothing. Machined surface images were applied in the estimation of machined surface quality. The images were decomposed using two-dimensional Discrete Wavelet Transform. The approximation component was analyzed and described by the features representing the geometric parameters of image objects. Determined values of image features were used to create the model of the process and estimation of appropriate time of micro-smoothing.

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Authors and Affiliations

Anna Zawada-Tomkiewicz
Ryszard Ściegienka
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Abstract

The radiolarian biostratigraphy of the Middle–Upper Jurassic pelagic siliceous sediments (Czajakowa Radiolarite

Formation) in the Niedzica succession of the Pieniny Klippen Belt (Carpathians) is interpreted in terms of their

age in a stratotype section, and facies equivalents in other tectonic-facies units of this region. The siliceous sediments

are represented by radiolarian cherts and silicified limestones which are underlain and overlain by red nodular

limestones, equivalents of the Rosso Ammonitico facies. The radiolarian association includes thirty-seven

taxa belonging to twenty one genera which represent the Northern Tethyan Palaeogeographic Province. Key radiolarians

recorded provide a means of correlation with zonation schemes based on Unitary Associations defined

for the Jurassic Tethyan sediments. The age of the Czajakowa Radiolarite Formation in the stratotype section

is determined as U.A.Z.9 to U.A.Z.11 corresponding to middle Oxfordian up to Kimmeridgian. Comparison of

radiolarian biozones from the stratotype section with other facial equivalent sections in the Pieniny Klippen Belt

reveals a significant diachronism for both the lower and the upper limits of the Jurassic pelagic siliceous facies.

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Authors and Affiliations

Marta Bąk
Sylwia Chodacka
Krzysztof Bąk
Szymon Okoński
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Abstract

Palaeomagnetic−petrographic−structural analyses of Proterozoic–Lower Palaeozoic metamorphosed carbonates from 12 locations within Oscar II Land (Western Spitsbergen) have been carried out to determine their usefulness in palaeogeographic reconstructions for Caledonian time. Structural analyses confirm that metacarbonates record several stages of deformation: D1, D2 ductile phases related to Caledonian metamorphism and a D3 brittle phase related to Late Cretaceous–Paleogene evolution of the West Spitsbergen Fold Belt. The latter is represented by thrust faults, localized folds with strain slip cleavages and late extensional collapse. Petrographic investigations reveal that Caledonian greenschist facies metamorphism was characterized by the high activity of H 2 O−CO 2 −rich fluids which promoted extensive recrystallization and within−rock spatial reorganization of sampled meta carbonates. Microscopic, SEM and microprobe analyses exclude the existence of any primary pre−metamorphic ferromagnetic minerals (primary−related to sedimentation and or early diagenesis) and point to metamorphic 4C superstructure (Fe 7 S 8 ) pyrrhotite as the main ferromagnetic carrier in investigated rocks. This is confirmed by the three−component isothermal remanent magnetization (IRM) procedures and the results of thermal demagnetizations. In 12 sites a total number of 72 independently oriented palaeomagnetic samples were collected from which 181 specimens were drilled and thermally demagnetized. Sampled metacarbonates are weakly magnetized (NRM <0.2mA/m). The statistically significant palaeomagnetic results were achieved only from 1 of 12 investigated sites. In one site situated in the Western overturned limb of the Holmesletfjellet Syncline intermediate unblocking temperatures – “pyrrhotite related” component WTSJ5M superimposed on the S1 Caledonian schistosity was recognized (D = 100.7 ° , I = −21.4 °a 95% = 5.5 ° , k = 58.23). Coincidence of WTSJ5M with Silurian–Devonian sector of the Baltica reference path after unfolding of the syncline by the angle of 130 ° suggests synfolding origin of this direction. Further, this suggests that Holmesletfjellet Syncline originated as an open fold and has been transformed into an overturned syncline during the Late Caledonian shortening or in the Late Cretaceous–Palaeogene time.
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Authors and Affiliations

Krzysztof Michalski
Justyna Domańska-Siuda
Krzysztof Nejbert
Geoffrey Manby
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Abstract

A total number of 156 palaeomagnetic specimens of metacarbonates from 9 sites in Blomstrandhalvøya and Lovénøyane (Kongsfjorden, western Spitsbergen) and an additional 77 specimens of unmetamorphosed sediments infilling fractures (4 sites) within the Caledonian metamorphic basement of Blomstrandhalvøya were demagnetized. No relicts of pre-metamorphic magnetization were identified. The Natural Remanent Magnetization (NRM) pattern of metacarbonates is dominated by Caledonian (sensu lato) – Svalbardian and Late Mesozoic/Cenozoic secondary magnetic overprints carried by the pyrrhotite and magnetite/maghemite phases, respectively. The NRM of unmetamorphosed sediments infilling the karstic/tectonic fractures is dominated by hematite carrier. It revealed three stages of magnetization: Caledonian sensu lato, Carboniferous and Late Mesozoic/Cenozoic, which can be related to their initial fracturing, karstification and sedimentation or reactivation. As the majority of the palaeopoles calculated for the Kongsfjorden sites fit the 430 – 0 Ma sector of Laurussia reference path in an in situ orientation these results support the hypothesis that Blomstrandhalvøya and Lovénøyane escaped main Eurekan deformations. The potential rotation of the Kongsfjorden basement by any west dipping listric fault activity rotating the succession accompanying the opening of North Atlantic Ocean was not documented by the palaeomagnetic data presented here.
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Authors and Affiliations

Krzysztof Michalski
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Abstract

The Rzeszów thrust-top basin was formed on the active Skole thrust sheet of the Outer Carpathian fold-andthrust belt and filled with Miocene syntectonic sediments. New seismic 3D, well and field data were used to define the relationship between sedimentation and tectonic activity and to establish the synkinematic context of the Rzeszów basin-fill architecture. The basin evolution was controlled by the activity of the Carpathian frontal thrust and hinterland thrusts developed in the forelimbs of folds in the Skole thrust sheet, bounding the basin from the north and south, respectively. The activity of the frontal thrust resulted in hinterland-directed depocentre migration and tilting of the syntectonic stratigraphic sequence. Balanced cross-sections have indicated that during the last compressive stage of deformation, the syntectonic deposits filling the basin were shortened by c. 5%, which resulted in the formation of folds and contractional faults. The architecture of the syntectonic deposits and the development of contractional structures reflect the activity of thrusts bounding the basin during compressive deformation of the Carpathian orogenic belt.

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Authors and Affiliations

Joanna Uroda
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Abstract

The damage zones of exhumed strike-slip faults dissecting Jurassic carbonates in the south-western part of the Late Palaeozoic Holy Cross Mountains Fold Belt reveal second-order faults and fractures infilled with syntectonic calcite. The subsequent development of a structural pattern of microscopic fault-related structures and calcite infillings reflects the activity of strike-slip faults that began in the Late Cretaceous (Late Maastrichtian) and lasted until the early Miocene (Langhian). The fabric of the syntectonic veins provides insights into the evolution of the permeable fault-related structures that were the main pathways for fluid flow during fault activity. Microstructural study of calcite veins coupled with stable isotope and fluid inclusion data indicates that calcite precipitated primarily in a rock-buffered system related to strike-slip fault movement, and secondarily in a partly open system related to the local activity of the releasing Chmielnik stepover or the uplift of the area. The presence of meteoric fluids descending from the surface into damage zones suggest that the strike-slip faulting might have taken place in a nonmarine, continental environment.

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Authors and Affiliations

Barbara Rybak-Ostrowska
Andrzej Konon
Vratislav Hurai
Maciej Bojanowski
Agnieszka Konon
Michał Wyglądała

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