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Number of results: 84
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Abstract

Urbanization has a far-reaching impact on the environment, economy, political and social processes. Therefore, understanding the spatial distribution and evolution of human settlements is a key element in planning strategies that ensure the sustainable development of urban and rural settlements. Accordingly, it is very important to map human settlements and to monitor the development of cities and villages. Therefore, the problem of settlements has found its reflection in the creation of global databases of urban areas. Global settlement data have extraordinary value. These data allow us to carry out the quantitative and qualitative analyses as well as to compare the settlement network at a regional, national and global scale. However, the possibility of conducting both spatial and attribute analyses of these data would be even more valuable. The article describes how to prepare raster data so that they can be implemented into a vector database. It answers the questions whether it is possible to combine these data with databases available in Poland and what benefits it brings. It presents the methods of data generalization and the optimization of time and disk space. As a result of the study, two vector databases with GUF data were developed. The first database resolution is similar to the original (~12 m resolution) database, the second database contains less detailed (~20 m resolution) data, generalized using mathematical morphology. Both databases have been enriched with descriptive data obtained from the National Geodetic and Cartographic Resource.

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Authors and Affiliations

Małgorzata Brzezińska-Klusek
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Abstract

The aim of my article will be the analysis of the results of the empirical research concerning the process of acquisition of English article system by Polish learners, carried out at three different levels of L2 acquisition.

English articles, as a semantic category non-existent in Polish, constitute a notorious source of difficulties in their acquisition by Poles. Polish learners of English at the beginning of their education, being at the elementary level, do not actually acquire articles because of the lack of associations with Polish counterparts. The semantics of English articles differs while compared to Polish, where instead of the articles: a/an, the demonstrative pronouns occur, e.g. ten (this), tamten (that) or there exists a different word order, different intonation, verbal aspects and many other syntactic-semantic processes.

While teaching English, we may easily observe that the process of acquisition of English article system by Polish learners differs depending on the level of advancement in learning English. In my article I would like to familiarize the addressees with the question of acquisition of articles by young teenagers, late teenagers and young adults. I hope the results of my research will evoke an interesting source for scientific discourse.

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Authors and Affiliations

Artur Świątek
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Abstract

The aim of any industrial plant, which is dealing in the energy sector, is to maximise the revenue generation at the lowest production cost. It can be carried out either by optimizing the manpower or by improving the performance index of the overall unit. This paper focuses on the optimisation of a biomass power plant which is powered by G50 hardwood chips (Austrian standard for biomass chips). The experiments are conducted at different operating conditions. The overall effect of the enhanced abilities of a reactor on the power generation is examined. The output enthalpy of a generated gas, the gas yield of a reactor and the driving mechanism of the pyrolysis are examined in this analysis. The thermal efficiency of the plant is found to vary from 44 to 47% at 400◦C, whereas it is 44 to 48% for running the same unit at 600 ◦C. The transient thermal condition is solved with the help of the lumped capacitance method. The thermal efficiency of the same design, within the constraint limit, is enhanced by 5.5%, whereas the enthalpy of the produced gas is magnified by 49.49% through nonlinear optimisation. The temperature of biomass should be homogenous, and the ramping rate must be very high. The 16% rise in temperature of the reactor is required to reduce the mass yield by 20.17%. The gas yield of the reactor is increased by up to 85%. The thermal assessment indicates that the bed is thermally thin, thus the exterior heat transfer rate is a deciding factor of the pyrolysis in the reactor.

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Authors and Affiliations

Alok Dhaundiyal
Suraj B. Singh
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Abstract

High voltage direct current (HVDC) emergency control can significantly improve the transient stability of an AC/DC interconnected power grid, and is an important measure to reduce the amount of generator and load shedding when the system fails. For the AC/DC interconnected power grid, according to the location of failure, disturbances can be classified into two categories: 1) interconnected system tie-line faults, which will cause the power unbalance at both ends of the AC system, as a result of the generator rotor acceleration at the sending-end grid and the generator rotor deceleration at the receiving-end grid; 2) AC system internal faults, due to the isolation effect of the DC system, only the rotor of the generator in the disturbed area changes, which has little impact on the other end of the grid. In view of the above two different locations of disturbance, auxiliary power and frequency combination control as well as a switch strategy, are proposed in this paper. A four-machine two-area transmission system and a multi-machine AC/DC parallel transmission system were built on the PSCAD platform. The simulation results verify the effectiveness of the proposed control strategy.

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Authors and Affiliations

Congshan Li
ORCID: ORCID
Ping He
ORCID: ORCID
Youyi Wang
Yuyi Ji
Cunxiang Yang
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Abstract

This paper proposes two high-order sliding mode algorithms to achieve highperformance control of induction motor drive. In the first approach, the super-twisting algorithm (STA) is used to reduce the chattering effect and to improve control accuracy. The second approach combines the super-twisting algorithm with a quasi-barrier function technique. While the super-twisting algorithm (STA) aims at the chattering reduction, the Barrier super-twisting algorithm (BSTA) aims to eliminate this phenomenon by providing continuous output control signals. The BSTA is designed to prevent the STA gain from being over-estimated by making these gains to decrease and increase according to system’s uncertainties. Stability and finite-time convergence are guaranteed using Lyapunov’s theory. In addition, the two controlled variables, rotor speed, and rotor flux modulus are estimated based on the second-order sliding mode (SOSM) observer. Finally, simulations are carried out to compare the performance and robustness of two control algorithms without adding the equivalent control. Tests are achieved under external load torque, varying reference speed, and parameter variations.
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Bibliography

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Authors and Affiliations

Salah Eddine Farhi
1
Djamel Sakri
1
Noureddine Golèa
1

  1. Laboratory of Electrical Engineering and Automatic, LGEA, Larbi Ben M’hidi University, Oum El Bouaghi, Algeria
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Abstract

The rainfall irregularity in the Al-Hoceima area places the Ghis-Nekor coastal aquifer as a primary resource for water supply. However, it is of paramount priority to adopt management and optimization plans that can mitigate the effects of the irrational use of the resource and the deterioration of its quality in the region of our study. In order to study the alteration aspects of this aquifer, 26 wells were sampled and their suitability for irrigation was assessed. The sodium adsorption rate (SAR) values indicate that most groundwater samples fall into the risk classes of high salinity and low sodium (C3-S1) and high salinity and medium sodium (C3-S2). The results also show a medium to high alkalinity risk due to the high concentration of HCO3–. The excess of salts is largely due to the intensive exploitation of groundwater and to the phenomenon of salt-water intrusion into the coastal karst aquifer. As a result, the quality of groundwater is not adapted to sustainable agricultural production and soil balance, which requires controlled monitoring to ensure its rational use with a view to the sustainable development of the region.
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Authors and Affiliations

Said Benyoussef
1 2
ORCID: ORCID
Mourad Arabi
3
ORCID: ORCID
Hossain El Ouarghi
2
ORCID: ORCID
Mohammad Ghalit
4
ORCID: ORCID
Yassine El Yousfi
2
ORCID: ORCID
Maryam Azirar
1
ORCID: ORCID
Ali Ait Boughrous
1
ORCID: ORCID

  1. University of Moulay Ismaïl, Faculty of Science and Technology Errachidia, Department of Biology, Research team: Biology, Environment and Health, Meknes, Morocco
  2. Abdelmalek Essaadi University, National School of Applied Sciences, Laboratory of Applied Sciences, Al Hoceima, Morocco
  3. Mohamed First University, Faculty of Sciences, Department of Biology, Laboratory of the Agricultural Production Improvement, Biotechnology, and Environment, P.B. 717, Oujda, Morocco
  4. Mohammed Premier University, Faculty of Science, Department of Chemistry, Laboratory of Mineral and Analytical Solid Chemistry, Oujda, Morocco
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Abstract

Emerging researches in humans, pigs and mice, highlighted that estrogen plays a pivotal role in self-renewal and differentiation of bone marrow mesenchymal stem cells (BMSCs). The present study aimed at evaluating effects of 17 beta-estradiol (E2) on proliferation and apoptosis of canine-derived bone marrow mesenchymal stem cells (cBMSCs) in vitro. The results showed that E2 supplementation at the concentration of 10-11 M promoted the proliferation of cBMSCs by CCK-8 assay and RT-qPCR analysis for the proliferation-related genes, with proliferating cell nuclear antigen (PCNA), cyclin-D1 (CCND1) being up-regulated and cyclin-dependent kinase inhibitor 1B (CDKN1B) being down-regulated. Contrarily, analysis of fluorescence-activated cell sorting (FACS) and RT-qPCR demonstrated that E2 supplementation above 10-11 M had inhibitory effects on the proliferation of cBMSCs and induced apoptosis. Intriguingly, cBMSCs still possessed the capability to differentiate into osteoblasts and adipocytes with 10-11 M E2 addition. Taken together, this study determined the optimal culture condition of cBMSCs in vitro, and has important implications for further understanding the regulatory effect of E2 on the self-renewal of cBMSCs, which are helpful for the clinical application of BMSCs.

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Authors and Affiliations

Z.-H. Zhou
C.-W. Gu
J. Li
X.-Y. Huang
J.-Q. Deng
L.-H. Shen
S.-Z. Cao
J.-L. Deng
Z.-C. Zuo
Y. Wang
ORCID: ORCID
X.-P. Ma
Z.-H. Ren
S.-M. Yu
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Abstract

An intelligent security model for the big data environment is presented in this paper. The proposed security framework is data sensitive in nature and the level of security offered is defined on the basis of the data secrecy standard. The application area preferred in this work is the healthcare sector where the amount of data generated through the digitization and aggregation of medical equipment’s readings and reports is huge. The handling and processing of this great amount of data has posed a serious challenge to the researchers. The analytical outcomes of the study of this data are further used for the advancement of the medical prognostics and diagnostics. Security and privacy of this data is also a very important aspect in healthcare sector and has been incorporated in the healthcare act of many countries. However, the security level implemented conventionally is of same level to the complete data which not a smart strategy considering the varying level of sensitivity of data. It is inefficient for the data of high sensitivity and redundant for the data of low sensitivity. An intelligent data sensitive security framework is therefore proposed in this paper which provides the security level best suited for the data of given sensitivity. Fuzzy logic decision making technique is used in this work to determine the security level for a respective sensitivity level. Various patient attributes are used to take the intelligent decision about the security level through fuzzy inference system. The effectiveness and the efficacy of the proposed work is verified through the experimental study.
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Authors and Affiliations

Somya Dubey
1
Dhanraj Verma
1

  1. Dr. A. P. J. Abdul Kalam University, Indore, India
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Abstract

This work describes a dual band compact fully integrated rectenna circuit for implantable medical devices (IMDs). The implantable rectenna circuit consists of tunnel diode 10×10μm2 QW-ASPAT (Quantum Well Asymmetric Spacer Tunnel Layer diode) was used as the RF-DC rectifier due to its temperature insensitivity and nonlinearity compared with conventional SBD diode. SILVACO atlas software is used to design and simulate 100μm2 QW InGaAs ASPAT diode. A miniaturized dual band implantable folded dipole antenna with multiple L-shaped conducting sections is designed using CST microwave suits for operation in the WMTS band is 1.5GHz and ISM band of 5.8GHz. High dielectric constant material Gallium Arsenide (εr=12.94) and folded geometry helps to design compact antennas with a small footprint of 2.84mm3 (1×4.5×0.63) mm3. Four-layer human tissue model was used, where the antenna was implanted in the skin model at depth of 2mm. The 10-dB impedance bandwidth of the proposed compact antenna at 1.5GHz and 5.8GHz are 227MHz (1.4-1.63GHz) with S11 is -22.6dB and 540MHz (5.47-6.02GHz) with S11 is -23.1dB, whereas gains are -36.9dBi, and -24.3dBi, respectively. The output DC voltage and power of the rectenna using two stage voltage doubler rectifier (VDR) are twice that produced by the single stage at input RF power of 10dBm.
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Authors and Affiliations

Shamil H. Hussein
1
Khalid K. Mohammed
1 2

  1. Faculty of Engineering University of Mosul, Iraq
  2. University of Nineveh, Iraq
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Abstract

Defending against DoS (denial of service) attacks has become a great challenge, especially for institutions that provide access to their services in the public network. State-of-the-art identity concealing tools and vast number of computers connected to the network require ensuring appropriate means for entities at risk to enable defence from the particular type of threats. This article presents a concept of user authentication in IP communication. The concept consists in providing the receiver with the possibility to determine sender՚s identity at the Internet layer level. This provides both the capability of defence against DoS attacks and possibility of utilizing the presented model over existing Internet network, which is directly responsible for transmission. The authors hope that the concept is a significant step in the perception of public network data transmission.

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Authors and Affiliations

Ł. Apiecionek
J.M. Czerniak
M. Romantowski
D. Ewald
B. Tsizh
H. Zarzycki
W.T. Dobrosielski
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Abstract

In March 2022, the European Commission presented its long-awaited legislative proposal on the EU-wide human rights and environmental due diligence (HREDD) for business. This article argues that the proposed Directive fails to be an effective and innovative legislation in three respects. Firstly, it does not draw lessons from the shortcomings of the to-date regulatory policy relating to business and human rights. It mainly consolidates at the EU level the status quo of extant due diligence legislation in Europe. Secondly, the proposal falls short of the established international standards and its own objectives insofar as it fails to establish instruments for effectively preventing and remedying human rights and environmental harm. Thirdly, the proposal’s normative preference for process- (rather than result-) oriented HREDD risks reducing it to yet another compliance instrument. Beside amending these shortcomings, to achieve a breakthrough, the upcoming legislation should in any case define HREDD as the legal standard of care; the compliance with which does not per se exclude civil liability. The general negotiation approach of the Council is not proposing much improvement in that regard. The stakes for the European Parliament’s possible role to raise the bar are thus very high.
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Authors and Affiliations

Izabela Jędrzejowska-Schiffauer
1
ORCID: ORCID
Łukasz Szoszkiewicz
1
ORCID: ORCID
Joseph Wilde-Ramsing
2
Katharine Booth
3
ORCID: ORCID
Pauline Barraud de Lagerie
4
ORCID: ORCID
Beata Faracik
5
ORCID: ORCID

  1. Faculty of Law and Administration, Adam Mickiewicz University
  2. Centre for Research on Multinational Enterprises (SOMO) in Amsterdam
  3. Centre for Research on Multinational Enterprises (SOMO) and Researcher/Policy Advisor at OECD Watch in Amsterdam
  4. PSL University
  5. BHR expert, Co-founder and President of the board of the Polish Institute of Human Rights and Business
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Abstract

Compositional and textural data are presented for zircon, secondary Zr-silicates, catapleiite and elpidite in a peralkaline granite from the Ilímaussaq complex, south Greenland. The zircon is essentially stoichiometric, with (Zr + Hf + Si) = 1.96–1.98 a.p.f.u. The secondary Zr-silicates show a wide range of Zr/Si atomic ratios (0.13–0.79). The catapleiite varies from close to stoichiometric to a Na-depleted type showing cation deficiency (5.2–5.8 a.p.f.u.). Elpidite shows similar variations (7.2–9.0 a.p.f.u.). Textural relationships between the Zr phases are interpreted to show that magmatic zircon interacted with hydrous fluids exsolved from the magma to form the secondary Zr-silicates. Formation of catapleiite was late‑magmatic, in equilibrium with a Na-Sibearing fluid. This was followed by the crystallization of elpidite, the fluid having a different Na/Si ratio. Both catapleiite and elpidite experienced Na-loss during late-stage hydrothermal alteration.
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Authors and Affiliations

Małgorzata Cegiełka
1 2
Bogusław Bagiński
1
Ray Macdonald
1 3
Harvey E. Belkin
4
Jakub Kotowski
1
Brian G.J. Upton
5

  1. Department of Geochemistry, Mineralogy and Petrology, Faculty of Geology, University of Warsaw, ul. Żwirki i Wigury 93, 02-089 Warsaw, Poland
  2. Institute of Geological Sciences, Polish Academy of Sciences, Research Centre in Warsaw, ul. Twarda 51/55, 00-818 Warsaw, Poland
  3. Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
  4. 11142 Forest Edge Drive, Reston, VA 20190, USA
  5. Grant Institute, University of Edinburgh, James Hutton Rd., Edinburgh EH9 3FE, UK
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Abstract

This article describes silver specimens of the size of tenths to a few millimetres, found in small pegmatites and quartz veinlets of the porphyritic granitoid area in 22 sites in the eastern part of the Variscan granitoid Karkonosze pluton, from 20 of which native silver occurrences were previously not known. The sites are scattered on the whole surface of the granitoid. The native silver occurred in wire, rod, platy, dendritic, anhedral granular and euhedral cubic and octahedral habits; in some specimens twins and fenster faces were also found. Associated with native silver small amounts of acanthite crystallized commonly, sometimes apparently formed by sulphur diffusion into silver. Inclusions of native gold, electrum, galena, chalcopyrite and pyrite occurred in the native silver. The parent fluids of the specimens were epithermal, because the homogenization temperature (Th) of inclusions in quartz, calcite and cleavelandite that were the host minerals of the native silver was generally 91–165ºC and for individual samples the Th range was 4–11ºC. The total salinity of the fluid was 2.4–7.2 wt. % with Na and Ca (hydro)carbonates as the main dissolved components and admixtures of K, Mg, Fe, Al, S, Cl and F. The parent granitoid contains Ag in trace amounts (0.034–0.056 ppm) and was probably the source of this element for the crystals of native silver. Migration of Ag was made easier by the presence of fluoride ions in fluids.
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Authors and Affiliations

Andrzej Kozłowski
1
Witold Matyszczak
1

  1. University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, 02-089 Warszawa, Poland
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Abstract

The time period of a jet engines full acceleration (from idle run rotating speed to full thrust) is a very important operational parameter. Minimization of this period is an important problem to be solved during the design of the fuel supply and control system. There are many methods of acceleration process control, especially in the case of engines with complicated design configurations. This work presents the problem of acceleration of a simple, single spool turbine jet engine with a so-called stable geometry, in which only one input (control) signal exists - fuel flow rate. Two methods of acceleration control consisting of limitation of the maximum allowable temperature of working medium in front of and behind the turbine in transient states were analyzed. In order to avoid difficulties associated with the direct measurement of actual temperatures, the so-called nonlinear engine observer was applied. With the use of the computer simulation method it was proven that the control algorithm with the limited maximum temperature in front of the turbine makes it possible the shortening of the acceleration time period significantly in comparison with a similar algorithm, that realizes the limitation of temperature behind the turbine.
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Authors and Affiliations

Wojciech I. Pawlak
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Abstract

The application of tuned liquid column dampers (TLCD) for suppressing excessive lateral pedestrian-induced vibrations of footbridges is investigated experimentally and numerically. In order to study the effectiveness of TLCD, a novel three-degree-of-freedom (DOF) bridge model is constructed in the laboratory of the TU-Institute. A single TLCD is attached to the bridge model to counteract the bridge's fundamental vibration mode. Modal tuning of the TLCD is performed using an analogy to tuned mass damper (TMD). A new excitation device has been developed for simulating the time-periodic contact forces due to walking pedestrians. All vibration tests performed indicate a large reduction of the maximum lateral vibration response amplitude. In order to verify the experimental results, numerical simulations of the laboratory model are performed, which show a good agreement. The application ofTLCD at least doubles the effective modal damping coefficient when compared to the original bridge model.
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Authors and Affiliations

Michael Reiterer
Markus J. Hochrainer
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Abstract

The paper describes a mathematical model of gas flow through crevices between the piston, rings and cylinder in internal combustion engines. The model has been developed to study the influence of numerous. design parameters and engine operation condition on piston ring pack behaviour and the exhaust gases blowby from the combustion chamber to the crankcase. The model integrates the gas flow and axial rings displacements in the grooves, and separately treats lands between piston, cylinder and adjacent rings and regions in the grooves behind the rings. The heat transfer between the gas and the surrounding surfaces is calculated and emphasis is placed on considering the influence of wear and thermal deformations of elements on ring pack performance.
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Authors and Affiliations

Grzegorz Koszałka
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Abstract

The French revolution should be conceived in its entirety: not as a coup by reformist elites or a retrogressive people’s movement, but a phenomenon transforming social mentality by means of opposing and related factors such as fear and violence, hope etc. The scope of influence of revolutionary mentality was considerable, especially considering more than just those social circles directly involved in the revolution.

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Authors and Affiliations

Michel Vovelle
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Abstract

The paper presents the results of testing the bearing resistance of the bolted joints of thin-walled profiles used in modular construction. The two types of joints currently applied in the construction industry were subjected to tests. One of them served as the reference sample, and the other as the research sample, which was used to find a solution that is more favorable in terms of the complexity of its production process and its bearing resistance. In addition to the modified shape of the end-plates, the bearing resistance of the joint was also analyzed with regards to the different diameters of bolts (bolts M12 and M16 were used), their classes (the difference between bolts of class 8.8 and 10.9 was examined), and also the number of them in the joint (3 or 5 bolts). Moreover, two thicknesses of steel sheets (3 mm and 4 mm), from which thin-walled cold-bent profiles were made, were used in the research. The bearing resistance tests were carried out with the use of a testing press of the authors’ own design. On the basis of the measurements, plots of the dependence between the deflection of the samples and the force acting in the middle of their span were drawn. It was shown that the tested profile joint had an increased bearing resistance by up to 26% when compared to the reference sample. The maximum destructive bending moment M was equal to 10.7 kN·m for the reference sample, and to 13.5 kN·m for the analyzed design solution. In total, 6 types of modified joints were made for the tests, of which five showed a comparable or higher bearing resistance than the reference sample. Each type of joint was tested by bending it in two directions in relation to the central axis of its cross-section.
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Authors and Affiliations

Karol Prałat
1
ORCID: ORCID
Arkadiusz Plis
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Mechanics and Petrochemistry, Łukasiewicza 17, 09-400 Płock, Poland
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Abstract

Biskupin is one of the most recognizable archaeological site in Poland and Central Europe. The origins of the excavations dates back to year 1934 and had lasted almost continuously until 1974. In the framework of the grant from the Ministry of Culture and National Heritage interdisciplinary team of scientists from Archaeological Museum in Biskupin and Warsaw University of Technology performed multi-dimensional analysis of the settlement. Based on the integrated vector documentation, resulting from the photographic documentation, numerical models of structural systems of main types of buildings and defensive rampart were prepared. The aim of the analysis was a verification of the earlier findings of archaeological and architectural researches. The analysis allowed to verify both the arrangement of individual parts of structure of buildings, their work and the interconnection, as well as the possible dimensions of the individual components.

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Authors and Affiliations

Wojciech Terlikowski
ORCID: ORCID
Martyna Gregoriou-Szczepaniak
ORCID: ORCID
Ewa Sobczyńska
ORCID: ORCID
Kacper Wasilewski
ORCID: ORCID
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Abstract

The paper presents the results of laboratory tests of SCB (semi-circular beam) samples of asphalt concrete, subjected to the destructive effect of water and frost as well as the aging processes. The determined values of material parameters show significant dispersions, which makes the design of mixtures difficult. Statistical analysis of the test results supplemented by computer simulations made with the use of the proprietary FEM model was carried out. The main distinguishing feature of the model is the assignment of material parameters of coarse aggregate and bituminous mortar to randomly selected finite elements. The parameters of the mortar are selected by trial and error to match the numerical results to the experimental ones. The stiffness modulus of the bituminous mortar is, therefore, a substitute parameter, taking into account the influence of many factors, including material degradation resulting from the aging and changing environmental conditions, the influence of voids, and contact between the aggregate and the bituminous mortar. The use of the Monte Carlo method allows to reflect the scattering of the results obtained based on laboratory tests. The computational algorithm created in the ABAQUS was limited only to the analysis of the global mechanical bending response of the SCB sample, without mapping the failure process in detail. The combination of the results of laboratory tests usually carried out on a limited number of samples and numerical simulations provide a sufficiently large population of data to carry out a reliable statistical analysis, and to estimate the reliability of the material designed.
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Authors and Affiliations

Cezary Szydłowski
1
ORCID: ORCID
Łukasz Smakosz
2
ORCID: ORCID
Marcin Stienss
1
ORCID: ORCID
Jarosław Górski
2
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, Department of Highway and Transportation Engineering, 11/12 Gabriela Narutowicza Street, 80-233 Gdansk, Poland
  2. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, Department of Structural Mechanics, 11/12 Gabriela Narutowicza Street, 80-233 Gdansk, Poland

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