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Number of results: 7
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Abstract

Defining species boundaries, due to morphological variation, often represents a significant challenge in paleozoology. In this paper we report results from multi− and univariate data analyses, such as enhanced clustering techniques, principal coordinates ordination method, kernel density estimations and finite mixture model analyses, revealing some morphometric patterns within the Eocene Antarctic representatives of Palaeeudyptes penguins. These large−sized birds were represented by two species, P. gunnari and P. klekowskii , known mainly from numerous isolated bones. Investigations focused on tarsometatarsi, crucial bones in paleontology of early penguins, resulted in a probability−based framework allowing for the “fuzzy” partitioning the studied specimens into two taxa with partly overlapping size distributions. Such a number of species was supported by outcomes from both multi− and univariate studies. In our opinion, more reliance should be placed on the quantitative analysis of form when distinguishing between species within the Antarctic Palaeeudyptes .
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Authors and Affiliations

Piotr Jadwiszczak
Carolina Acosta Hospitaleche
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Abstract

The paper presents an evaluation with the Type A and B methods for standard uncertainties of coefficients of a polynomial function of order k determined by n points obtained by measurement of input and output quantities. A method for deriving a posteriori distributions of function coefficients based on the transformation of estimator distributions without assuming any a priori distributions is presented. It was emphasized that since the correct values of the standard uncertainty of type A depend on the √ n-k-3 and not on the p √ n-k-1, therefore, with a small number of measurement points, the use of the classical approach leads to a significant underestimation of uncertainty. The relationships for direct evaluation with the type B method of uncertainties caused by uncorrected systematic additive (offset error) and multiplicative (gain error) effects in the measurements of both input and output quantities are derived. These standard uncertainties are determined on the basis of the manufacturers’ declared values of the maximum permissible errors of the measuring instruments used. A Monte Carlo experiment was carried out to verify the uncertainties of the coefficients and quadratic function, the results of which fully confirmed the results obtained analytically.
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Authors and Affiliations

Mykhaylo Dorozhovets
1 2

  1. Rzeszow University of Technology, Faculty of Electrical and Computer Engineering, Department of Metrology andDiagnostic Systems, Wincentego Pola, 2A, 35-959 Rzeszow, Poland
  2. Lviv Polytechnic National University, Institute of Computer Technologies, Automation and Metrology, Department ofInformation Measuring Technology, Bandera str., 12, 79013 Lviv, Ukraine
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Abstract

Digital twin (DT) is a solution for presenting reality in a virtual world. DTs have been discussed in the literature only recently. The aim of this work is to review and analyse literature connected to DTs. Under a systematic literature review the authors searched databases for the information how DTs can support organization operations and how they can support sustainability of companies. A literature review was performed according to a developed research methodology, which covers research questions and keywords identification, selection criteria and results analysis. Databases, such as Web of Science, Scopus and Science Direct, were searched. The titles, abstracts and keywords were searched for works related to digital twins, sustainable development and manufacturing processes. Moreover, the search was focused on real-time monitoring, data, decision-making etc. The keywords used in the searching process are specified in the methodology. Afterwards, quantitate and qualitative analysis were performed taking into account number of publication, year of publications, type of publication, based on keywords and available information concerning the papers. Deeper analysis was performed on available full texts of the papers. The main goal of this paper was to assess how much the specified problem is discussed in literature in the context of production organizations and real-time and what kind of topics are present in publications to indicate future research needs.
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Authors and Affiliations

Jerzy Pater
Dorota Stadnicka
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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 objective of this article is to carry out a systematic review of the literature on multivariate statistical process control (MSPC) charts used in industrial processes. The systematic review was based on articles published via Web of Science and Scopus in the last 10 years, from 2010 to 2020, with 51 articles on the theme identified. This article sought to identify in which industry the MSPC charts are most applied, the types of multivariate control charts used and probability distributions adopted, as well as pointing out the gaps and future directions of research. The most commonly represented industry was electronics, featuring in approximately 25% of the articles. The MSPC chart most frequently applied in the industrial sector was the traditional T2 of Harold Hotelling (Hotelling, 1947), found in 26.56% of the articles. Almost half of the combinations between the probabilistic distribution and the multivariate control graphs, i.e., 49.4%, considered that the data followed a normal distribution. Gaps and future directions for research on the topic are presented at the end.
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Authors and Affiliations

Renan Mitsuo Ueda
1
Ìcaro Romolo Sousa Agostino
2
Adriano Mendonça Souza
1

  1. Federal University of Santa Maria, Brazil
  2. Federal University of Santa Catarina, Brazil
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Abstract

Agile Project Management is a topic that has become popular both in business and academia, since the publication of the Agile Manifesto – a historic landmark in this subject. In the next 20 years, there was a relevant scientific production that must be analyzed to provoke reflection about the knowledge built up in this period. In this sense, this study aims to analyze the relevant scientific literature on Agile Project Management through a systematic review and a bibliometric analysis of articles published in scientific journals with Digital Object Identifier, in English, from the Web of Science and Scopus databases, from 2001 to 2021. The research results enable us to gain insights into the characteristics of this knowledge domain, regarding its volume and evolutionary trend, main contributors (i.e. scientific journals, authors, and their affiliations), main studies, methods used, and its central thematic axes.
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Authors and Affiliations

Antonio Carlos Pacagnella Junior
1
Vinicius Romeiro da Silva
1

  1. State University of Campinas, School of Applied Sciences, Production Engineering Center (CENPRO), Brazil
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Abstract

The author discusses systematization of scientific disciplines. He presents two methods of systematization, namely: classification which uses logical divisions, and typologization which relies on Weberian method of defining ideal types. Faced with certain weaknesses of the classification and typologization, the author proposes still another method of science systematization, which he calls ‘theoretical positioning’. Such systematization is accomplished by defining a selected theory with respect to the research processes employed in it. At the time when interdisciplinary studies are becoming more and more popular, theoretical positioning is a useful method of systematization for research purposes. It arranges scientific disciplines in an order that displays their theoretical affinities. That method of systematization not only organizes the multitude of scientific disciplines but also indicates which areas of cooperation can be most promising. Alongside that study, the author also discusses the possibility of theoretical positioning of sciences by employing conceptual categories used in theory of action which, appropriately conceptualized, could serve as effective interdisciplinary instruments.
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Authors and Affiliations

Mieszko Ciesielski
1
ORCID: ORCID

  1. Uniwersytet im. Adama Mickiewicza w Poznaniu, Instytut Kultury Europejskiej, ul. Kostrzewskiego 5–7, 62‑200 Gniezno

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