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Abstract

Industry 4.0 (I4) as a concept offers powerful opportunities for many businesses. The set of Industry 4.0 technologies is still discussed, and boundaries are not perfectly clear. However, implementation of Industry 4.0 concept becomes strategic principle, and necessary condition for succeeding on turbulent markets. Radio Frequency Identification (RFID) was used before I4 emerged. However, it should be treated as its important part and even enabler. The question arises how adoption of RFID was impacted by I4 paradigm. Therefore, to answer this question a set of technology management tools was selected and applied to forecast RFID potential development in forthcoming years. Moreover, case studies were conducted for technology management tools and their applications for RFID for qualitative discussion of its relevance. It aimed to prove that existing toolset should be applied for modern technologies related to I4. Tools were proven to be necessary and successful. However, some specific challenges were observed and discussed.
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Authors and Affiliations

Bartlomiej Gladysz
1
Donatella Corti
2
Elias Montini
2

  1. Warsaw University of Technology, Institute of Production Systems Organization, Warsaw, Poland
  2. University of Applied Science and Arts of Southern Switzerland, Department of Innovative Technologies
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Abstract

In this work, the level of influence of the posts published by famous people on social networks on the formation of the cryptocurrency exchange rate is investigated. Celebrities who are familiar with the financial industry, especially with the cryptocurrency market, or are somehow connected to a certain cryptocurrency, such as Elon Musk with Dogecoin, are chosen as experts whose influence through social media posts on cryptocurrency rates is examined. This research is conducted based on statistical analysis. Real cryptocurrency exchange rate forecasts for the selected time period and predicted ones for the same period, obtained using three algorithms, are utilized as a dataset. This paper uses methods such as statistical hypotheses regarding the significance of Spearman’s rank correlation coefficient and Pearson’s correlation. It is confirmed that the posts by famous people on social networks significantly affect the exchange rates of cryptocurrencies.
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Authors and Affiliations

Sergii Telenyk
ORCID: ORCID
Grzegorz Nowakowski
ORCID: ORCID
Olena Gavrilenko
Mykhailo Miahkyi
Olena Khalus
ORCID: ORCID
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Abstract

Celem pracy była wstępna charakterystyka (mineralogiczna, chemiczna, teksturalna) odpadów poflotacyjnych, stanowiących surowiec uboczny (odpadowy) przy uzyskiwaniu koncentratów cynkowo-ołowiowych, pod kątem dalszych analiz nad możliwością ich perspektywicznego (eksperymentalnego) wykorzystania jako sorbentów gazów kwaśnych (SO2 i CO2). Składowisko tych odpadów jest własnością ZGH 'Bolesław' w Bukownie. Materiał badawczy stanowiła próbka odpadów poflotacyjnych pobrana ze stawu osadowego nr 1, leżącego w południowej części Stawu Zachodniego. Charakterystyka wytypowanych do badań materiałów obejmowała podstawowe badania mineralogiczne (XRD, SEM-EDS), analizy chemiczne (oznaczenie zawartości wilgoci analitycznej, zawartości strat prażenia, podstawowego składu chemicznego, jak też pierwiastków śladowych) oraz wyznaczenie podstawowych parametrów teksturalnych (powierzchnia właściwa BET, rozkład i wielkość porów). Badania mineralogiczne wykazały, że materiał odpadowy stanowią głównie minerały węglanowe (w przewadze kalcyt, dolomit, ankeryt) oraz minerały stanowiące pozostałość po niewyflotowanych kruszcach (w przewadze galena, sfaleryt). Analiza chemiczna pozwoliła stwierdzić, iż w analizowanej próbce dominują związki wapnia, magnezu i żelaza uwarunkowane przewagą minerałów węglanowych w badanych odpadach. Wśród pierwiastków śladowych przeważa arsen, następnie mangan i bar, występujące jednak w ilości nie przekraczającej 1%. Analiza teksturalna wykazała, że materiał badawczy charakteryzuje się niską powierzchnią właściwą i dużymi rozmiarami cząstek. Przeprowadzone badania sugerują, że analizowany materiał charakteryzuje się ubogimi właściwościami adsorpcyjnymi, aczkolwiek mógłby on znaleźć zastosowanie w metodach odsiarczania, jak też neutralizacji dwutlenku węgla (karbonizacja). Należałoby jednak w tym celu przeprowadzić dodatkowe badania wymywalności metali ciężkich w środowisku kwasowym, jak też zastosować domieszki innych składników, takich jak cement czy zeolity, w celu immobilizacji niebezpiecznych składników odpadów.

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Authors and Affiliations

Magdalena Wdowin
Agnieszka Gruszecka
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Abstract

The aim of the study was to assess the profile of EC (elemental carbon) and OC (organic carbon) temperature fractions in PM1 and PM2.5 samples and in wet deposition samples (material collected on a filter). The research was conducted at the urban background station in Zabrze (southern Poland) in the period of Oct 2020–Oct 2021. PM samples were collected with high-volume samplers; the automatic precipitation collector NSA 181 by Eigenbrodt was used to collect the deposition samples. Concentrations of EC and OC were determined using thermal-optical method (carbon analyzer from Sunset Laboratory Inc., “eusaar_2” protocol). Regardless of the type of research material, organic carbon constituted the dominant part of the carbonaceous matter, and this dominance was more visible in the non-heating season. The profile of temperature fractions of OC and EC was clearly different for dust washed out by precipitation. Noteworthy is a much lower content of pyrolytic carbon (PC) in OC, which can be explained by the fact that PC is most often combined with the water soluble organic carbon. In addition, a high proportion of the OC3 fraction was observed, followed by OC4, which may indicate that these fractions are of a more regional origin. With regard to the EC fractions, the differences are less visible and concern, in particular, the higher share of EC4 and the lower EC2. The obtained results may be a valuable source of information about the actual status of the carbonaceous matter and its transformation in the atmosphere.
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Authors and Affiliations

Barbara Błaszczak
1
Barbara Mathews
1
Krzysztof Słaby
1
Krzysztof Klejnowski
1

  1. Institute of Environmental Engineering Polish Academy of Sciences, Zabrze, Poland
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Abstract

This paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Główny and Gdańsk Śródmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing parts of the structure allow us to determine environmental excitations used for validation and verification of the derived FEM model. The numerical calculations made the estimates of the vibration amplitudes propagating throughout the whole structure possible.

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Authors and Affiliations

M. Miśkiewicz
Ł. Pyrzowski
M. Rucka
K. Wilde
J. Chróscielewski
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Abstract

This paper presents new procedure modeling based on finite element method analysis of wood-framed timber structures. The fasteners linking boards of sheathing with the timber frame both modeled applying shell finite element, with individual material parameters, remain the main objective of this manuscript. Material parameters are obtained from experimental tests and numerical identification. The main objective of the paper is the elaboration of the numerical model with high precision of mapping, and, at the same time, diminishing the number of the unknown simplifying the process of the modeling of timber structures. The new presented method leads to a simplification of analysis of multistory wood-framed multifamily building structures.

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Authors and Affiliations

J. Malesza
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Abstract

The influence that general contractors and subcontractors have on the operation of a company is immense. Keeping this in mind, the authors have decided to develop and algorithm based on the analysis of partnering relations between construction companies that would select the best possible construction company for the purposes of cooperation. This algorithm, developed for a given construction company, is meant to support its decision-making system in the field of the selection of another construction company to cooperate with. The author has made references to earlier research, in which she had used the ELECTRE III method, and in which she bad analysed the possibility of applying the BIPOLAR method in order to solve the problem of the selection of a construction company to develop partnering relations with. The author provided an example of the calculations performed for a selection of construction companies.

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Authors and Affiliations

E. Radziszewska-Zielina
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Abstract

In order to identify the modal parameters of civil structures it is vital to distinguish the defective data from that of appropriate and accurate data. The defects in data may be due to various reasons like defects in the data collection, malfunctioning of sensors, etc. For this purpose Exploratory Data Analysis (EDA) was engaged toenvisage the distribution of sensor’s data and to detect the malfunctioning with in the sensors. Then outlier analysis was performed to remove those data points which may disrupt the accurate data analysis. Then Data Driven Stochastic Sub-space Identification (DATA-SSI) was engaged to perform the modal parameter identification. In the end to validate the accuracy of the proposed method stabilization diagrams were plotted. Sutong Bridge, one of the largest span cable stayed bridge was used as a case study and the suggested technique was employed. The results obtained after employing the above mentioned techniques are very valuable, accurate and effective.

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Authors and Affiliations

I. Khan
D. Shan
Q. Li
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Abstract

In order to achieve extended life of asphalt pavement, one of key points is to achieve a good bonding between it’s components. This research paper presents findings on the topic of influence of polyethylene bitumen modification on the adhesion between bitumen and aggregate. A novel method of quantifying the bitumen coated area, based on computer image analysis, has been developed for this study. Two different methods of adhesion testing were employed, namely boiling water method and the rolling bottle method. Aggregates used in this study were granite and limestone. Based on 108 measurements, it was concluded that polyethylene modification has a negative impact on binder aggregate adhesion.

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Authors and Affiliations

D. Brożyna
K. J. Kowalski
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Abstract

The research paper presents the results of the dynamic analysis of an existing bar dome subjected to wind loads. The calculation model of the structure was constructed using the finite element method. The dome was subjected to the standard wind pressure, assuming that it is operates in a harmonic manner. The numerical analyses were performed with the application of Autodesk Robot and MES3D. The analysis focused on the impact of selected factors such as the frequency of forcing, wind gustiness coefficient and structural damping on the behaviour of structures.

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Authors and Affiliations

W. Szaniec
K. Zielińska
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Abstract

This paper presents application of optical microscope for evaluation of microtexture changes of coarse aggregate during simulated polishing in laboratory. Observations of the apparent changes on surfaces of seven different aggregates are presented. Simulation polishing of aggregate was performed in accordance with PN-EN 1097-8:2009. lmages of the aggregate surface were taken with the optical microscope in the reflection mode in particular stages of polishing. Digital images were analyzed. Standard deviation was determined on the basis of the histogram of intensities from digital images of the surfaces of aggregate grains which was assurned as the measure of changes in microtexture during simulated polishing (namely the σh parameter). Statistical analysis has shown that the changes of the σh parameter between the particular stages of polishing confirm certain trends related to the petrographic characteristic of the rocks. Aggregates which included minerals of similar hardness (granodiorite, dolomile, basalt) were more prone to polishing than gabbro and postglacial. Regeneration of the microtexture, the recovery to its original asperity, occurred in the case of quartz sandstone and steelmaking slag.

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Authors and Affiliations

W. Gardziejczyk
M. Wasilewska
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Abstract

The preliminary stage of asphalt mixture production involves the drying and dedusting of coarse aggregates. The most common types of coarse aggregates used are limestone and basalt. In the process of drying and dedusting the dryer filter accumulates large quantities of waste in the form of mineral powder.

This paper introduces an investigation into limestone powder waste as a potential microfiller of polymer composites. Physical characteristics such as the granulation the of powder collected from the filter - in terms of the season of its collection and the type of input materials used - were analysed. A scanning electron microscope (SEM) was used for the investigation described within this paper. The obtained results were compared against those of other materials which can be used as polymer composites microfillers.

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Authors and Affiliations

M. Kępniak
P. Woyciechowski
W. Franus
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Abstract

Probabilistic analysis of a space truss is presented in the paper. Reliability of such a structure is sensitive to geometrical and material imperfections. The objective of this paper is to present a variant of the point estimate method (PEM) to determine mean values and standard deviations of limit loads of engineering structures. The main advantage presented by this method is the small number of sample calculations required to obtain estimators of investigated parameters. Thus the method is straightforward, requiring only preliminaries of probability theory. This approach is illustrated by limit state analysis of a space truss, considering geometric and material imperfections. The calculations were performed for different random models, so the influence of random parameters on the limit load of the truss can be determined. A realistic snow load was imposed.

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Authors and Affiliations

P. Sorn
J. Górski
J. Przewłócki
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Abstract

The paper presents an analysis of the influence of elevated temperature on thin-walled purlins restrained by sheeting. In the first part of the study the bearing capacity of purlins cooperating with sheeting is examined in normal and elevated temperature based on European Standards. Next, special attention is paid to creating a numerical FEM model of the restrained purlins in Abaqus program taking into account different materials properties with respect to temperature increase.

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Authors and Affiliations

K. Rzeszut
Ł. Polus
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Abstract

For the construction company, tendering is the most popular way of acquiring contracts. The decision to participate in the tender needs to be made carefully, as it affects the condition of the company and is an important aspect in its quest for success. The bid/no bid decision making is a complex process involving a number of factors. The research carried out so far has mainly concerned the identification of the various kinds of influences on contractors’ bidding decisions. The researchers, on the basis of contractors’ opinions, created rank lists in an attempt to categorize the factors. In this paper the author employs factor analysis which belongs to basic methods of multi-dimensional data analysis. The paper’s aim is first to depict an output set of observed variables, that is bid/no bid factors, in terms of a smaller set of latent variables which cannot be directly observed and then to interpret the dependencies between them.

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Authors and Affiliations

A. Leśniak
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Abstract

The standard PN-EN_1993-1-5:_2008 (Eurocode 3) compared with the standard (PN-B-03200:_1990) used previously in Poland, introduces extended rules referring to the computations of the bearing capacity of the plated structural elements including the shear lag effect. The stress distribution in the width flanges is variable. Therefore in the case of the beam with the shear lag effect cannot be calculated by the classic beam theory.

In this article a comparison of the results of the calculations of forces distribution, stresses and displacement according to the rule presented in PN-EN_1993 and results of the numerical computations for_3D model (using finite element method) is presented. The elastic shear lag effects, the elastic shear lag effects including effects of the plate buckling and the elastic-plastic shear lag effects including the local instabilities were analysed. The calculations were performed for beams with a small and a large span and an influence of stiffeners was analysed.

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Authors and Affiliations

M. Szumigała
K. Ciesielczyk
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Abstract

Transportation networks respond differently to applied policies. The Tehran Metropolitan Area has one of the most complex networks with complex users, which has experienced many of these policies change within the past decades. In this study, some of these policies and their effect on air pollution is investigated. The goal is to pinpoint the variables which have the most effect on various transportation models and investigate how new policies should be focused. In order to do so, long-term variations of air pollution monitoring stations were analyzed. Results show that the most significant parameter that may affect air pollution is users' behavior due to the lack of a public transportation network and its level of comfort. The results of this study will be useful in developing new policies and evaluating their long-term consequences in appropriate models.

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Authors and Affiliations

Mansour Hadji Hosseinlou
Shahab Kabiri
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Abstract

The problems related to construction production are multi-faceted and complex. This has promoted the search for different methods/approaches for analizing the data which supports the decision-making process in the construction industry. In the article the authors focus their attention on well-known methods and tools, and on some new approaches to solving decision-making problems. The aim of the article is to analyze the methods used to analyse data in a construction company, convey their advantages and disadvantages, and specify the degree of efficiency in the discussed area.

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Authors and Affiliations

A. Dziadosz
A. Kończak
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Abstract

During the planning and controlling of the construction process, most attention is focu sed on risk analysis, especially in the context of final costs and deadlines of the investment. In this analysis, the primary and most significant concern is the proper identification and quantification of events, which on a certain level of probability may affect the development process. This paper presents the result of a risk analysis for a particular building object, made after completion of the investment and accepting it for use. Knowledge of the planned values and the actual investment process allowed for the identification of the events and their effects that in this case have significantly disrupted the investment process. The limited total cost of the investment project in question had a considerable impact on the progress of the project execution. Despite three transitions of administrative procedures, the opening date of the shopping centre was delayed by only three weeks.

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Authors and Affiliations

M. Lendo-Siwicka
M. Połoński
K. Pawluk
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Abstract

Buckling and postbuckling response of thin-walled composite plates investigated experimentally and determinated analytically and numerically is compared. Real dimension specimens of composite plates weakened by cut-out subjected to uniform compression in laboratory buckling tests have been modelled in the finite element method and examined analytically based on P-w2 and P-w3 methods. All results were obtained during the experimental investigations and the numerical FEM analysis of a thin-walled composite plate made of a carbon-epoxy laminate with a symmetrical eight-layer arrangement of [90/-45/45/0]s. The instrument used for this purpose was a numerical ABAQUS® program.

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Authors and Affiliations

K. Falkowicz
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Abstract

Numerical analysis of the tensioning cables anchorage zone of a bridge superstructure is presented in this paper. It aims to identify why severe concrete cracking occurs during the tensioning process in the vicinity of anchor heads. In order to simulate the tensioning, among others, a so-called local numerical model of a section of the bridge superstructure was created in the Abaqus Finite Element Method (FEM) environment. The model contains all the important elements of the analyzed section of the concrete bridge superstructure, namely concrete, reinforcement and the anchoring system. FEM analyses are performed with the inclusion of both material and geometric nonlinearities. Concrete Damage Plasticity (CDP) constitutive relation from Abaqus is used to describe nonlinear concrete behaviour, which enables analysis of concrete damage and crack propagation. These numerical FEM results are then compared with actual crack patterns, which have been spotted and inventoried at the bridge construction site.

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Authors and Affiliations

J. Chróscielewski
M. Miśkiewicz
Ł. Pyrzowski
B. Sobczyk
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Abstract

This paper concerns an approach to model the ledger-stand joints of modular scaffolds. Based on the analysis of the working range of the ledger (represented by a linear relationship between load and displacement), two models of the ledger-stand joint are analysed: first – with flexibility joints and second – with rigid joints and with a transition part of lower stiffness. Parameters are selected based on displacement measurements and numerical analyses of joints, then they are verified. On the basis of performed research, it can be stated that both methods of joint modelling recommended in this paper, can be applied in engineering practices.

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Authors and Affiliations

E. Błazik-Borowa
M. Pieńko
A. Robak
A. Borowa
P. Jamińska-Gadomska
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Abstract

Light-weight Self-Compacting Concrete (LWSCC) might be the answer to the increasing construction requirements of slenderer and more heavily reinforced structural elements. However there are limited studies to prove its ability in real construction projects. In conjunction with the traditional methods, artificial intelligent based modeling methods have been applied to simulate the non-linear and complex behavior of concrete in the recent years. Twenty one laboratory experimental investigations on the mechanical properties of LWSCC; published in recent 12 years have been analyzed in this study. The collected information is used to investigate the relationship between compressive strength, elasticity modulus and splitting tensile strength in LWSCC. Analytically proposed model in ANFIS is verified by multi factor linear regression analysis. Comparing the estimated results, ANFIS analysis gives more compatible results and is preferred to estimate the properties of LWSCC.

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Authors and Affiliations

B. Vakhshouri
S. Nejadi
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Abstract

The paper presents a proposal for the assessment of the reliability of steel truss (both statically determinate and indeterminate) in the persistent and accidental design situation. In the analysis, a probabilistic approach was used. The global Hasofer-Lind reliability index was employed, computed in successive time steps for the whole structure, not for individual elements. The statically determinate truss was modelled as a serial system from the reliability standpoint. For the statically indeterminate truss, kinematically admissible failure mechanisms were determined by means of the examination of the singularity of the stiffness matrix of the structure, converting the truss into a geometrically variable system. For the problem thus formulated, a serial-parallel reliability model was constructed. Monitoring the reliability index in the successive minutes of the fire makes it possible to estimate the probability of the structure failure, and to decide whether the required safety level is maintained.

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Authors and Affiliations

K. Kubicka
U. Radoń

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