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Abstract

Material of tesseraspids (Tesseraspidiformes) is reported from the uppermost Severnaya Zemlya Formation

(Lochkovian, Lower Devonian) of the Severnaya Zemlya archipelago, in the Russian Arctic, where it is associated

with other vertebrate remains, including corvaspids, acanthodians, and large but rare specimens of

osteostracans. The tesseraspid material is not abundant, and most often preserved as a “patchwork” of bony

platelets (tesserae), except for a few partly articulated specimens. We redescribe the holotype of Tesseraspis

mosaica Karatajūtė-Talimaa, 1983, whose head carapace is preserved as a flattened tube of adjacent tesserae.

This material is compared to the already published tesseraspid taxa, i.e., T. tessellata Wills, 1935, T. toombsi

Tarlo, 1964, T. mutabilis (Brotzen, 1934), T. oervigi Tarlo, 1964 emend. Dineley and Loeffler, 1976, T. denisoni

Tarlo, 1964, and T. talimaae Tarlo, 1965. All species are based upon rare and incomplete material, as no

head carapaces associated with trunk and tail are known, and so, the intraspecific variability is also unknown.

Distinction between “species” is based on the detail of the superficial sculpture of the tesserae of the head carapaces,

which is unsatisfactory. It is concluded that only four of the nominal species can be retained. A review

of all other known tessellated pteraspidomorphs indicates that our knowledge of tessellated heterostracans is

currently insufficient to support a meaningful classification.

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Authors and Affiliations

Blieck Alain
David K. Elliott
Valentina N. Karatajūtė-Talimaa
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Abstract

The paper proposes a new, state space, finite dimensional, fractional order model of a heat transfer in one dimensional body. The time derivative is described by Caputo operator. The second order central difference describes the derivative along the length. The analytical formulae of the model responses are proved. The stability, convergence, and positivity of the model are also discussed. Theoretical results are verified by experiments.
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Bibliography

[1] R. Almeida and D.F.M. Torres: Necessary and sufficient conditions for the fractional calculus of variations with caputo derivatives. Communications in Nonlinear Science and Numerical Simulation, 16(3), (2011), 1490–1500, DOI: 10.1016/j.cnsns.2010.07.016.
[2] A. Atangana and D. Baleanu: New fractional derivatives with non-local and non-singular kernel: theory and application to heat transfer. Thermal Sciences, 20(2), (2016), 763–769, DOI: 10.2298/TSCI160111018A.
[3] R. Caponetto, G. Dongola, L. Fortuna, and I. Petras: Fractional order systems: Modeling and Control Applications. In: Leon O. Chua, editor, World Scientific Series on Nonlinear Science, pages 1–178. University of California, Berkeley, 2010.
[4] S. Das: Functional Fractional Calculus for System Identyfication and Control. Springer, Berlin, 2010.
[5] M. Dlugosz and P. Skruch: The application of fractional-order models for thermal process modelling inside buildings. Journal of Building Physics, 39(5), (2016), 440–451, DOI: 10.1177/1744259115591251.
[6] A. Dzielinski, D. Sierociuk, and G. Sarwas: Some applications of fractional order calculus. Bulletin of the Polish Academy of Sciences, Technical Sciences, 58(4), (2010), 583–592, DOI: 10.2478/v10175-010-0059-6.
[7] C.G. Gal and M. Warma Elliptic and parabolic equations with fractional diffusion and dynamic boundary conditions. Evolution Equations and Control Theory, 5(1), (2016), 61–103, DOI: 10.3934/eect.2016.5.61.
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[9] T. Kaczorek: Singular fractional linear systems and electrical circuits. International Journal of Applied Mathematics and Computer Science, 21(2), (2011), 379–384, DOI: 10.2478/v10006-011-0028-8.
[10] T. Kaczorek and K. Rogowski: Fractional Linear Systems and Electrical Circuits. Bialystok University of Technology, Bialystok, 2014.
[11] A. Kochubei: Fractional-parabolic systems, preprint, arxiv:1009.4996 [math.ap], 2011.
[12] W. Mitkowski: Approximation of fractional diffusion-wave equation. Acta Mechanica et Automatica, 5(2), (2011), 65–68.
[13] W. Mitkowski: Finite-dimensional approximations of distributed rc networks. Bulletin of the Polish Academy of Sciences. Technical Sciences, 62(2), (2014), 263–269, DOI: 10.2478/bpasts-2014-0026.
[14] W. Mitkowski,W. Bauer, and M. Zagorowska: Rc-ladder networks with supercapacitors. Archives of Electrical Engineering, 67(2), (2018), 377– 389, DOI: 10.24425/119647.
[15] K. Oprzedkiewicz: The discrete-continuous model of heat plant. Automatyka, 2(1), (1998), 35–45 (in Polish).
[16] K. Oprzedkiewicz: The interval parabolic system. Archives of Control Sciences, 13(4), (2003), 415–430.
[17] K. Oprzedkiewicz:Acontrollability problem for a class of uncertain parameters linear dynamic systems. Archives of Control Sciences, 14(1), (2004), 85–100.
[18] K. Oprzedkiewicz: An observability problem for a class of uncertainparameter linear dynamic systems. International Journal of Applied Mathematics and Computer Science, 15(3), (2005), 331–338.
[19] K. Oprzedkiewicz:Non integer order, state space model of heat transfer process using Caputo-Fabrizio operator. Bulletin of the Polish Academy of Sciences. Technical Sciences, 66(3), (2018), 249–255, DOI: 10.24425/122105.
[20] K. Oprzedkiewicz: Non integer order, state space model of heat transfer process using Atangana-Baleanu operator. Bulletin of the Polish Academy of Sciences. Technical Sciences, 68(1), (2020), 43–50, DOI: 10.24425/bpasts.2020.131828.
[21] K. Oprzedkiewicz: Positivity problem for the one dimensional heat transfer process. ISA Transactions, 112, (2021), 281-291 DOI: .
[22] K. Oprzedkiewicz: Fractional order, discrete model of heat transfer process using time and spatial Grünwald-Letnikov operator. Bulletin of the Polish Academy of Sciences. Technical Sciences, 69(1), (2021), 1–10, DOI: 10.24425/bpasts.2021.135843.
[23] K. Oprzedkiewicz, K. Dziedzic, and Ł. Wi˛ eckowski: Non integer order, discrete, state space model of heat transfer process using Grünwald-Letnikov operator. Bulletin of the Polish Academy of Sciences. Technical Sciences, 67(5), (2019), 905–914, DOI: 10.24425/bpasts.2019.130873.
[24] K. Oprzedkiewicz and E. Gawin: A non-integer order, state space model for one dimensional heat transfer process. Archives of Control Sciences, 26(2), (2016), 261–275, DOI: 10.1515/acsc-2016-0015.
[25] K. Oprzedkiewicz, E. Gawin, and W. Mitkowski: Modeling heat distribution with the use of a non-integer order, state space model. International Journal of Applied Mathematics and Computer Science, 26(4), (2016), 749– 756, DOI: 10.1515/amcs-2016-0052.
[26] K. Oprzedkiewicz and W. Mitkowski: A memory-efficient nonintegerorder discrete-time state-space model of a heat transfer process. International Journal of Applied Mathematics and Computer Science, 28(4), (2018), 649–659, DOI: 10.2478/amcs-2018-0050.
[27] K. Oprzedkiewicz,W. Mitkowski, E.Gawin, and K. Dziedzic: The Caputo vs. Caputo-Fabrizio operators in modeling of heat transfer process. Bulletin of the Polish Academy of Sciences. Technical Sciences, 66(4), (2018), 501– 507, DOI: 10.24425/124267.
[28] K. Oprzedkiewicz, E. Gawin, and W. Mitkowski: Parameter identification for non integer order, state space models of heat plant. In MMAR 2016: 21th international conference on Methods and Models in Automation and Robotics: 29 August–01 September 2016, Międzyzdroje, Poland, pages 184– 188, 2016.
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[32] M. Rozanski: Determinants of two kinds of matrices whose elements involve sine functions. Open Mathematics, 17(1), (2019), 1332–1339, DOI: 10.1515/math-2019-0096.
[33] N. Al Salti, E. Karimov, and S. Kerbal: Boundary-value problems for fractional heat equation involving caputo-fabrizio derivative. New Trends in Mathematical Sciences, 4(4), (2016), 79–89, arXiv:1603.09471.
[34] D. Sierociuk, T. Skovranek, M. Macias, I. Podlubny, I. Petras, A. Dzielinski, and P. Ziubinski: Diffusion process modeling by using fractional-order models. Applied Mathematics and Computation, 257(1), (2015), 2–11, DOI: 10.1016/j.amc.2014.11.028.
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Authors and Affiliations

Krzysztof Oprzędkiewicz
1
ORCID: ORCID
Klaudia Dziedzic
1

  1. AGH University of Science and Technology in Krakow, Faculty of Electrical Engineering, Automatics, Computer Science and Robotics, Department of Automatics and Biomedical Engineering, Kraków, Poland
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Abstract

Maize dwarf mosaic virus (MDMV) is a serious and widespread virus pathogen of maize plants. This +ssRNA virus belongs to the Potyvirus genus in the Potyviridae family. Together with sugarcane mosaic virus (SCMV) it causes one of the most important viral diseases on maize crops in the world – maize dwarf mosaic. Both viruses are transmitted in the same non-persistent manner by several aphid species. They induce similar symptoms of leaf mosaic or mottling, stunting and a reduction in plant weight and grain yield. Available MDMV diagnostics include primarily commercialized enzyme-linked immunosorbent assays (ELISA) and reverse transcription-polymerase chain reactions (RT-PCR). Here, laborsaving reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay was optimized for identification of genetically different MDMV isolates. For this purpose, primer sets, MDMVF3/MDMVB3 and MDMVFIP/MDMVBIP amplifying fragments of coat protein coding sequence of MDMV, were used. The specificity of the reaction was verified using three MDMV (-P1, -Sp, -PV0802-DSMZ) and three SCMV (-P1, -PV0368- -DSMZ, -PV1207-DSMZ) isolates. Obtained products were visualised by DNA staining, electrophoretic separation as well as by real-time monitoring of the reaction. The sensitivity of RT-LAMP and conventional RT-PCR reactions was comparable. Both methods could detect virus as low as 550 fg · μl–1 of total RNA. This technique has application value for screening MDMV by phytosanitary services.
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Authors and Affiliations

Katarzyna Trzmiel
1
ORCID: ORCID
Beata Hasiów-Jaroszewska
1
ORCID: ORCID

  1. Department of Virology and Bacteriology, Institute of Plant Protection – National Research Institute, Poznan, Poland
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Abstract

The structure of the low-voltage distribution network often changes. The change of topology will affect fault detection, fault location, line loss calculation, etc. It leads to fault detection error, inaccurate positioning and abnormal line loss calculation. This paper presents a new method to automatically identify the topology of a low-voltage power grid by using the injection current signal. When the disturbance current signal is injected into the low-voltage line, the current upstream of the injection point will change, and the current downstream of the injection point will not be affected. It is proved theoretically by using the superposition principle. With this method, the disturbance current signal can be injected into the line in turn, and the topology can be identified by observing the change of the current in line. The correctness of the method is proved by Matlab simulation and laboratory verification.
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Bibliography

[1] Short T.A., Electric Power Distribution Handbook, Second Edition, Crc Press (2014).
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[3] Jiang J., Liu L., Resonance mechanisms of a single line-to-ground fault on ungrounded systems, Archives of Electrical Engineering, vol. 69, no. 2, pp. 455–466 (2020).
[4] Grotas S., Yakoby Y., Gera I. et al., Power Systems Topology and State Estimation by Graph Blind Source Separation, IEEE Transactions on Signal Processing, vol. 67, no. (8), pp. 2036–2051 (2019).
[5] Tianyu L., Research on Fault Analysis and Topology Identification Based on Power Line Communication, Master Thesis, Control Engineering, China University of Geosciences (Beijing) (2019).
[6] Xiangyu K., YutingW., Xiaoxiao Y. et al., Optimal configuration of PMU based on customized genetic algorithm and considering observability of multiple topologies of distribution network, Electric Power Automation Equipment, vol. 40, no. 1, pp. 66–72 (2020).
[7] Chao Y., The Development and Manufacture of a Multi-Function Equipment for Low Voltage Area Identifed, Master Thesis, Electrical Engineering, China Dalian University of Technology (2014).
[8] Ya L., Rusen F., Wei J. et al., Research on the intelligent transformer area recognition method based on BP neural network, Electrical Measurement & Instrumentation, vol. 54, no. 3, pp. 25–30 (2017).
[9] Dong-Feng Y., Su-Quan Z. et al., A Novel Method for Power Grid Topology Identification Based on Incidence Matrix Simplification, East China Electric Power, vol. 42, no. 11, pp. 2254–2259 (2014).
[10] Jing M., Yuyu Z. et al., Power Network Topological Analysis Based on Incidence Matrix Notation Method and Loop Matrix, Automation of Electric Power Systems, vol. 38, no. 12, pp. 74–80 (2014).
[11] Zeyang T., Kunpeng Z., Kan C. et al., Substation Area Topology Verification Method Based on Distribution Network Operation Data, High Voltage Engineering, vol. 44, no. 4, pp. 1059–1068 (2018).
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[13] Jing M., Yuyu Z., Wei M. et al., Power Network Topological Analysis Based on Incidence Matrix Notation Method and Loop Matrix, Automation of Electric Power Systems, vol. 38, no. 12, pp. 74–80 (2014).
[14] Zonghui W., Yu C., Bingyin X. et al., Logical Node Based Topology Identification of Distributed Feeder Automation, Automation of Electric Power Systems, vol. 44, no. 12, pp. 124–130.
[15] Zengping W., Jinfang Z., Yagang Z., A novel substation configuration identification algorithm based on the set of breaker-path functions, Proceedings of the CSEE, vol. 33, no. 1, pp. 137–145 (2013).


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Authors and Affiliations

Haotian Ge
1
Bingyin Xu
1
Wengang Chen
1
Xinhui Zhang
1
Yongjian Bi
1

  1. Shandong University of Technology, China
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Abstract

Kinetic studies of esterification reaction of maleic anhydride with butan-1-ol, 2-methylpropan-1-ol and butan-2-ol were carried out in a semibatch reactor, in the presence of four acidic catalysts: sulfuric acid, phosphotungstic acid, ion exchange resin Dowex 50WX8 and tetrabutyl zirconate. Phosphotungstic acid proved to be the most active catalyst. The temperature range was 383–413 K, the initial molar ratio of alcohol to acid ranged 2.2-5:1. The kinetic parameters were given. The kinetics appeared to be that of the second order with respect both to the acid and to the alcohol. The reaction carried out in the presence of tetrabutyl zirconate was very slow and depended only on acid concentration. The effect of temperature on the reaction rate follows the Arrhenius equation well.
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Authors and Affiliations

Maria Bartoszewicz
1
Maria Kulawska
2
Wiesław Organek
2

  1. Łukasiewicz Research Network – Institute of Heavy Organic Synthesis “Blachownia”, Energetyków 9, 47-225 Kędzierzyn-Koźle, Poland
  2. Polish Academy of Sciences, Institute of Chemical Engineering, Bałtycka 5, 44-100 Gliwice, Poland
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Abstract

In the recent times, lot of research work carried out in the field of fuel cells explicitly divulges that it has the potential to be an ultimate power source in upcoming years. The fuel cell has more storing capacity, which enables to use in heavy power applications. In these applications, power conditioning is more vital to regulate the output voltage. Hence, we need a dc-dc converter to provide a constant regulated output voltage for such high-power system. Currently, many new converters were designed and implemented as per the requirement. This paper has made comparative study on several topologies of the quadratic high gain dc-dc converter and the applications where these topologies can be used when the fuel cell is given as a source. Also, we have compared various parameters of all the converters considered and generated the results with steady-state and dynamic study. In this article, we briefed the types of analysis carried on the dc-dc converter to study its performance. Moreover, various application of fuel cell is presented and discussed. This paper will be a handbook to the researchers who start to work on high gain dc-dc converter topologies with quadratic boost converter as a base. This article will also guide the engineers to concentrate on the fuel cell components where it needs to be explored for optimizing its operation.
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Authors and Affiliations

Divya Navamani Jayachandran
1
Jagabar Sathik
2
Tanmay Padhi
1
Aditi Kumari
1

  1. Department of Electrical and Electronics Engineering, SRM Institute of Science and Technology, Kattankulathur, 603203, Chennai, India
  2. Renewable Energy Lab, Prince Sultan University,11586, Riyadh, Saudi Arabia
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Abstract

Mating electrodes made of copper alloys are commonly used for welding galvanized steel sheets used in the production of car bodies. These alloys are characterized by high mechanical properties, a high level of electrical and thermal conductivity as well as the stability of these properties under changing conditions of current, thermal and mechanical load. Much careful attention was paid to the essence of the ongoing structural changes as well as to the mechanical properties in the welding process (RSW – Resistant Spot Welding) of steel sheets, including high-strength ones. There is a lack of research on structural changes and the related mechanical properties occurring in welding electrodes made of copper alloys caused by the welding process.
This study is devoted to these issues and contains a critical review of the research results enabling a better understanding of the relationships between the structure and properties of welding electrodes caused by the cyclic welding process. In order to illustrate the phenomena occurring during the welding process, both in the material to be welded and in the tip electrodes, hardness and structural tests were carried out on electrode samples before and after their exploitation. The data collected in the article supplements a certain lack of information in the literature regarding the microstructural aspects of the welding process of galvanized steel sheets for the production of car bodies. The conducted research may be the starting point for the search for more effective materials for the tip electrodes.
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Authors and Affiliations

Z. Rdzawski
1
ORCID: ORCID
P. Kwaśniewski
2
ORCID: ORCID
W. Głuchowski
1
ORCID: ORCID
M. Łagoda
1
ORCID: ORCID
M. Maleta
1
ORCID: ORCID
S. Boczkal
3
ORCID: ORCID
K. Franczak
2
ORCID: ORCID

  1. Łukasiewicz Research Network – Institute of Non-Ferrous Metals, 5 Sowińskiego Street, 44-100 Gliwice, Poland
  2. AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland
  3. Łukasiewicz Research Network – Institute of Non-Ferrous Metals, Light Metals Division, 19 Piłsudskiego Street, 32-050 Skawina, Poland
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Abstract

The aim of the study was to develop a method of laparoscopic embryo transfer in pigs and to compare different variants of this method. Two catheter diameters (1.6 mm and 1.0 mm), the method and site of embryo deposition (oviduct or uterus), the embryo development stage (2 – 4 cell or blastocyst), the method for oviduct or uterus stabilization, the potential for cryopreserved embryo transfer, the developmental potential of the embryos after transfer to the oviduct, patomorphology of the oviduct after transfer and possible clinical complications were taken into consideration. Two studies compared two variants of transfer to the uterus, and five variants of transfer to the fallopian tube. The transfer of embryos by the infundibulum may be of limited use due to handling problems and very low efficiency (pregnancy was not achieved). Very low efficiency was shown after transfer of vitrified embryos. Transfer to the fallopian tube by puncture of the fallopian tube, regardless of the developmental stage of the embryo, is the recommended method of embryo transfer. The histopathological examination of the fallopian tube revealed possible changes within the puncture site. The numerous clinical complications observed did not affect the effectiveness of the method.
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Authors and Affiliations

J. Wieczorek
1
E. Stodolak-Zych
2
ORCID: ORCID
K. Okoń
3
J. Koseniuk
4
M. Bryła
5
J. Jura
5
K. Poniedziałek-Kempny
5
I. Rajska
5
K. Sobol
5
M. Kotula Balak
1
M. Chmurska-Gasowska
1

  1. University Centre of Veterinary Medicine, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
  2. Department of Biomaterials, Faculty of Materials Science and Ceramics, University of Science and Technology, Mickiewicza 30, 30-059 Krakow, Poland
  3. Chair of Pathomorphology, Collegium Medicum, Jagiellonian University, Grzegorzecka 16, 30-526 Krakow, Poland
  4. Artvimed Centre for Reproductive Medicine, Czyzowka 14, 30-526 Krakow, Poland
  5. Department of Reproductive Biotechnology and Cryoconservation, National Research Institute of Animal Production, Krakowska 1, 30-322 Balice/Krakow, Poland
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Abstract

In this work we consider a problem from the field of power- and energy-aware scheduling, in which a set of batteries have to be charged in a minimum time. The formulated problem is to schedule independent and nonpreemptable jobs to minimize the schedule length, where each job requires some amount of power and consumes a certain amount of energy during its processing. We assume that the power demand of each job linearly decreases with time, as it is the case when Li-ion batteries are being charged. For the assumed job model we prove that each next job should be started as soon as the required amount of power is available. Basing on the proven theorem we formulate a procedure generating a minimum-length schedule for an assumed order of jobs. We also analyze the case of identical jobs, and show some interesting properties of this case.

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Authors and Affiliations

R. Różycki
G. Waligóra
J. Węglarz
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Abstract

This contribution characterises the stratigraphic schemes of the Quaternary as constructed and published by Leszek Lindner in 1967–2019. The oldest schemes assume the subdivision of the Pleistocene into three glaciations (i.e., Cracow, Middle-Polish and Baltic) separated by two interglacials (Great and Eemian). The scheme published in 1992 comprises eight glacial and seven interglacial units. The most recent scheme for the Quaternary contains seven advances of the Scandinavian ice-sheet on the area of Poland during the Nidanian (MIS 22), Sanian 1 (MIS 16), Sanian 2 (MIS 12), Liviecian (MIS 10), Krznanian (MIS 8), Odranian (MIS 6), and Vistulian (MIS 2–5d) glaciations. They are separated by six interglacials: Podlasian, Ferdynandovian, Mazovian, Zbójnian, Lublinian and Eemian. The ranges of glacial transgressions, and key interglacial and preglacial sites are assembled in a cumulative scheme for the area of Poland. We review the main study methods on which the subsequent versions of the stratigraphic scheme were based. These include Prof. Lindner’s own detailed field research in glaciated and extraglacial areas, and paleofloristic, paleontological and paleomagnetic studies of major interglacial sites carried out by numerous researchers, as well as thorough literature studies.
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Authors and Affiliations

Jan Dzierżek
1
Bogusz Kulus
1

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

In the paper the results of experimental investigations concerning flat slabs made from reinforced lightweight concrete with sintered fly ash aggregate CERTYD were presented. In the research program 6 models made in a natural scale were included. The main variable parameter was slab longitudinal reinforcement ratio. The aim of investigation was the experimental verification of efficiency of double-headed studs as punching shear reinforcement. In the existing technical approvals such kind of reinforcement was allowed only in normal concrete slabs. It was demonstrated that double-headed studs can be an effective transverse reinforcement of lightweight aggregate concrete slabs. The use of double-headed studs resulted in increase in the ultimate load from 19% to 44%, depending on the slab reinforcement ratio which ranged from 0.5% to 1.2%. The comparative analysis showed that the Eurocode 2 provisions were conservative in relation to the experimental results, which were on average 42% higher than the theoretical ones however with a very low 7% coefficient of variation.

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Authors and Affiliations

M. Gołdyn
Ł. Krawczyk
W. Ryżyński
T. Urban
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Abstract

The bridge horizontal swivel system generally adopts a symmetrical structure and uses a spherical hinge structure that can adjust the rotation to complete rotation construction. Because of the complexity of railway lines under bridges, some asymmetrical horizontal swivel systems have been increasingly applied in practical engineering in recent years. This system is more suitable for areas with complex railway lines, reduces the bridge span, and provides better economic benefits. However, it is also extremely unstable. In addition, instability can easily occur under dynamic loads, such as earthquake action and pulsating wind effects. Therefore, it is necessary to study their mechanical behavior. Based on the horizontal swivel system of an 11,000-ton asymmetric continuous girder bridge, the dynamic response of the horizontal swivel system to seismic action was studied using the finite element simulation analysis method. Furthermore, using the Peer database, seismic waves that meet the calculation requirements are screened for time-history analysis and compared to the response spectrum method. The mechanical properties of the structural system during and after rotation were obtained through calculations. During rotation, the seismic response of the structure is greater. To reduce the calculation time cost, an optimization algorithm based on the mode shape superposition method is proposed. The calculation result is 87% that of the time-history analysis, indicating a relatively high calculation accuracy.
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Authors and Affiliations

Jiawei Wang
1
ORCID: ORCID
Hongshuai Gao
2
ORCID: ORCID
Kexin Zhang
3
ORCID: ORCID
Zongyun Mo
1
ORCID: ORCID
Hongchun Wang
1
ORCID: ORCID

  1. Anhui Polytechnic University, School of Architecture and Civil Engineering, Wuhu City, Beijing Middle Road, China
  2. Heilongjiang University, College of Civil Engineering, Harbin City, Xuefu Road, China
  3. Shenyang Jianzhu University, School of Architecture and Civil Engineering, Shenyang City, Hun Nan Road, China
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Abstract

The author summarizes the origin and development of the thaler since its emergence in Central Europe in the 1520s to the general spread of the term “thaler” for large silver coins in the 1540s as well as the attempts to replace the thaler with another type of coin in the Roman-German Empire under the Second and Third Imperial Coin Order. The year 1566 was a major turning point. The “imperial thaler” was redefined in metrological terms and the collection of custom duties in the North Sea straits was regulated, which (instead of gold coins) continued to be collected in silver thalers. This move spurred the expansion of the thaler coins in those countries of continental Europe that used the North Sea trade route. At that time, the thaler also became the equivalent for mutual conversions of the most important monetary systems. This is evidenced by the exchange rates from the end of the 16th century from Hamburg. In them, the ”imperial thaler” serves as a tool for the mutual conversion the seven major currencies used in the North Sea and Baltic trade areas (the Lübeck mark, the Hamburg pound, the Antwerp pound, the Amsterdam pound, the imperial Rhine gulden, the Lisbon milreis and the Polish gulden).
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Authors and Affiliations

Petr Vorel
1
ORCID: ORCID

  1. Faculty of Arts and Philosophy, University of Pardubice, Studentská 95, CZ 532 10 Pardubice, Czech Republic
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Abstract

Caballero P., Lopez-Ferber, M., Williams, T. (eds.). 2001. Los Baculovirus y sus Aplicaciones como Bioinsecticidas en el Control Biologico de Plagas [Baculoviruses and their Application as Bioinsecticides in Biological Control of Pests]. PHYTOMA-Espaiia, Universidad Publica de Navarra, Valencia. 2001. ISBN 84-9320256-0-5, 518 pp. Price: $35.80
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Authors and Affiliations

Jerzy Lipa
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Abstract

This paper proposes a method for offline accurate ball tracking for short volleyball actions in sport halls. Our aim is to detect block touches on the ball and to determinate accurate trajectory and impact positions of the ball to support referees. The proposed method is divided into two stages, namely training and ball tracking, and is based on background subtraction. Application of the Gaussian mixture model has been used to estimate a background, and a high-speed camera with a capture rate of 180 frames per second and a resolution of 1920 × 1080 are used for motion capture. In sport halls significant differences in light intensity occur between each sequence frame. To minimize the influence of these light changes, an additional model is created and template matching is used for accurate determination of ball positions when the ball contour in the foreground image is distorted. We show that this algorithm is more accurate than other methods used in similar systems. Our light intensity change model eliminates almost all pixels added to images of moving objects owing to sudden changes in intensity. The average accuracy achieved in the validation process is of 0.57 pixel. Our algorithm accurately determined 99.8% of all ball positions from 2000 test frames, with 25.4 ms being the average time for a single frame analysis. The algorithm presented in this paper is the first stage of referee support using a system of many cameras and 3D trajectories.

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Authors and Affiliations

P. Kurowski
K. Szelag
W. Zaluski
R. Sitnik
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Abstract

The activity of territorial self-government shaped institutionally during the development process is characterized by a significant scope of care for the financial situation, which determines the efficiency of its functioning. The general availability of public services is a condition for the assessment of the activities of municipalities (powiats, voivodeships). Institutional economy as a real one, takes into account an integrated point of view. The aim of the study is to present the territorial differentiation of the eff ectiveness of communes’ activities in the context of institutional economics and to present the possibility of using a synthetic measure in this process. The synthetic measure of development fluctuated within the limits of 0.30 – Wąchock (Starachowice poviat, urban-rural commune) to 0.41 – Ostrowiec Św. (Ostrowiecki poviat, urban commune) in 2009, 0.32 – Łączna (Skarżysko poviat, rural commune) to 0.40 – Starachowice (Starachowice poviat, municipal commune) in 2015. The results of the analysis confirm the existence of small differences in the assessment of development communes of the Kamienna Basin. This approach allows the assessment of municipalities using one size and allows you to organize the analyzed objects in terms of the considered phenomenon.

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Authors and Affiliations

Paweł Dziekański
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Abstract

The Committee on Acoustics of the Polish Academy of Sciences was founded in 1964 by the reso lution of the General Assembly of the Polish Academy of Sciences, within its Division of Engineering Sci ences (Division 4). The idea of creating the Committee was brought up by Professor Ignacy Malecki, a distinguished scientist, an academic teacher, and an internationally acclaimed authority on acoustics.

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Authors and Affiliations

Andrzej Rakowski
Antoni Śliwiński
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Abstract

Analysis of granulation kinetics was carried out using a laboratory disc granulator with a diameter D of 0.5 m. A liquid binder was delivered to the tumbling bed at a constant flow rate with a nozzle generating droplets with a size of approx. 4-5 mm. Fine-grained chalk was used as a model of raw material and water or disaccharide solution with concentrations of 20 - 40% as a wetting liquid. Different times of droplet delivery ranging from 2 to 6 min were utilized. Granulometric composition of the bed for selected lengths of process, bed moisture and the moisture of individual size-fractions were assessed. Mass of granulated material, which was transferred from nuclei fraction to other size fractions was determined on the basis of mass balance analysis and the assessment of liquid migration between fractions. The influence of disaccharide concentration in wetting liquid on the aforementioned phenomena was also examined.

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Authors and Affiliations

Andrzej Obraniak
Tadeusz Gluba
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Abstract

The ultrasonic flowmeter which is described in this paper, measures the transit of time of an ultrasonic pulse. This device consists of two ultrasonic transducers and a high resolution time interval measurement module. An ultrasonic transducer emits a characteristic wave packet (transmit mode). When the transducer is in receive mode, a characteristic wave packet is formed and it is connected to the time interval measurement module inputs. The time interval measurement module allows registration of transit time differences of a few pulses in the packet. In practice, during a single measuring cycle a few time-stamps are registered. Moreover, the measurement process is also synchronous and, by applying the statistics, the time interval measurement uncertainty improves even in a single measurement. In this article, besides a detailed discussion on the principle of operation of the ultrasonic flowmeter implemented in the FPGA structure, also the test results are presented and discussed

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Authors and Affiliations

Stanisław Grzelak
Marcin Kowalski
Jarosław Czoków
Marek Zieliński
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Abstract

This paper describes a new contactless conductivity detector, whose electrodes are constructed of microchannels filled with solution of KCl - called pseudoelectrodes. The lab-on-a-chip microdevice was fabricated in poly(dimethylsiloxane) PDMS, using a moulding technique. The mould was made from a dry negative photoresist with a thickness of 50 μm. During the tests, the dimension! and arrangement of pseudoelectrodes` microchannels were evaluated. The analyte was pumped into the microchannel using a syringe pump with a flow rate of 50 μL/min. Reproducible!changes of the signal were obtained.

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Authors and Affiliations

Karolina Blaszczyk
Michal Chudy
Zbigniew Brzózka
Artur Dybko
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Abstract

The quality of the supplied power by electricity utilities is regulated and of concern to the end user. Power quality disturbances include interruptions, sags, swells, transients and harmonic distortion. The instruments used to measure these disturbances have to satisfy minimum requirements set by international standards. In this paper, an analysis of multi-harmonic least-squares fitting algorithms applied to total harmonic distortion (THD) estimation is presented. The results from the different least-squares algorithms are compared with the results from the discrete Fourier transform (DFT) algorithm. The algorithms are assessed in the different testing states required by the standards.

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Authors and Affiliations

Pedro Ramos
Fernando Janeiro
Tomáš Radil

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