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Author Gielis, J.; Ricci, P.E.; Tavkhelidze, I.
Title The Möbius phenomenon in Generalized Möbius-Listing surfaces and bodies, and Arnold's Cat phenomenon Type (up) A1 Journal article
Year 2021 Publication Advanced Studies : Euro-Tbilisi Mathematical Journal Abbreviated Journal
Volume 14 Issue 4 Pages 17-35
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Möbius bands have been studied extensively, mainly in topology. Generalized Möbius-Listing surfaces and bodies providing a full geometrical generalization, is a quite new field, motivated originally by solutions of boundary value problems. Analogous to cutting of the original Möbius band, for this class of surfaces and bodies, results have been obtained when cutting such bodies or surfaces. In general, cutting leads to interlinked and intertwined different surfaces or bodies, resulting in very complex systems. However, under certain conditions, the result of cutting can be a single surface or body, which reduces complexity considerably. Our research is motivated by this reduction of complexity. In the study of cutting Generalized Möbius-Listing bodies with polygons as cross section, the conditions under which a single body results, displaying the Möbius phenomenon of a one-sided body, have been determined for even and odd polygons. These conditions are based on congruence and rotational symmetry of the resulting cross sections after cutting, and on the knife cutting the origin. The Möbius phenomenon is important, since the process of cutting (or separation of zones in a GML body in general) then results in a single body, not in different, intertwined domains. In all previous works it was assumed that the cross section of the GML bodies is constant, but the main result of this paper is that it is sufficient that only one cross section on the whole GML structure meets the conditions for the Möbius phenomenon to occur. Several examples are given to illustrate this.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000774655100002 Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:183081 Serial 8258
Permanent link to this record
 
 
Author Mescia, L.; Chiapperino, M.A.; Bia, P.; Gielis, J.; Caratelli, D.
Title Modeling of electroporation induced by pulsed electric fields in irregularly shaped cells Type (up) A1 Journal article
Year 2018 Publication IEEE transactions on biomedical engineering Abbreviated Journal
Volume 65 Issue 2 Pages 414-423
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract During the past decades, the poration of cell membrane induced by pulsed electric fields has been widely investigated. Since the basic mechanisms of this process have not yet been fully clarified, many research activities are focused on the development of suitable theoretical and numerical models. To this end, a nonlinear, nonlocal, dispersive, and space-time numerical algorithm has been developed and adopted to evaluate the transmembrane voltage and pore density along the perimeter of realistic irregularly shaped cells. The presented model is based on the Maxwell's equations and the asymptotic Smoluchowski's equation describing the pore dynamics. The dielectric dispersion of the media forming the cell has been modeled by using a general multirelaxation Debye-based formulation. The irregular shape of the cell is described by using the Gielis' superformula. Different test cases pertaining to red blood cells, muscular cells, cell in mitosis phase, and cancer-like cell have been investigated. For each type of cell, the influence of the relevant shape, the dielectric properties, and the external electric pulse characteristics on the electroporation process has been analyzed. The numerical results demonstrate that the proposed model is an efficient numerical tool to study the electroporation problem in arbitrary-shaped cells.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000422914700018 Publication Date 2017-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9294 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:148417 Serial 8264
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Author Chiapperino, M.A.; Bia, P.; Caratelli, D.; Gielis, J.; Mescia, L.; Dermol-Cerne, J.; Miklavcic, D.
Title Nonlinear dispersive model of electroporation for irregular nucleated cells Type (up) A1 Journal article
Year 2019 Publication Bioelectromagnetics Abbreviated Journal
Volume 40 Issue 5 Pages 331-342
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In this work, the electroporation phenomenon induced by pulsed electric field on different nucleated biological cells is studied. A nonlinear, non-local, dispersive, and space-time multiphysics model based on Maxwell's and asymptotic Smoluchowski's equations has been developed to calculate the transmembrane voltage and pore density on both plasma and nuclear membrane perimeters. The irregular cell shape has been modeled by incorporating in the numerical algorithm the analytical functions pertaining to Gielis curves. The dielectric dispersion of the cell media has been modeled considering the multi-relaxation Debye-based relationship. Two different irregular nucleated cells have been investigated and their response has been studied applying both the dispersive and non-dispersive models. By a comparison of the obtained results, differences can be highlighted confirming the need to make use of the dispersive model to effectively investigate the cell response in terms of transmembrane voltages, pore densities, and electroporation opening angle, especially when irregular cell shapes and short electric pulses are considered. Bioelectromagnetics. 2019;40:331-342. (c) 2019 Wiley Periodicals, Inc.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000472568200004 Publication Date 2019-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0197-8462 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:161282 Serial 8315
Permanent link to this record
 
 
Author Gielis, J.; Verhulst, R.; Caratelli, D.; Ricci, P.E.; Tavkhelidze, I.
Title On means, polynomials and special functions Type (up) A1 Journal article
Year 2014 Publication The teaching of mathematics Abbreviated Journal
Volume 17 Issue 1 Pages 1-20
Keywords A1 Journal article; Educational sciences; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1451-4966; 2406-1077 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:128660 Serial 8327
Permanent link to this record
 
 
Author Gielis, J.
Title Phi-bonacci in Ancient Greece Type (up) A1 Journal article
Year 2021 Publication Symmetry : culture and science Abbreviated Journal
Volume 32 Issue 1 Pages 25-40
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Fibonacci numbers are a very popular subject in mathematics, culture and science. A major open question is why the ancient Greeks overlooked this series, while they were very familiar with the golden mean and division in extreme and mean ratio. Furthermore, they could compute the square root of five to a high degree of precision using Theon 's ladder. This fact is based on tables built with side and diagonal numbers, and it is a simple and incredibly efficient method to compute roots of integers, though it is little known even now among most of the experts. The biologist D 'Arcy Wentworth Thompson showed that the same method could be used to generate the Fibonacci series using a simple shift in the computation of the tables. He argues, quite convincingly, that the ancient Greeks could not have overlooked this. Actually, the same method can be used to generate all possible regular phyllotaxis patterns.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000643822700002 Publication Date 2021-03-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0865-4824 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:178322 Serial 8376
Permanent link to this record
 
 
Author Shi, P.; Liu, M.; Yu, X.; Gielis, J.; Ratkowsky, D.A.
Title Proportional relationship between leaf area and the product of leaf length and width of four types of special leaf shapes Type (up) A1 Journal article
Year 2019 Publication Forests (19994907) Abbreviated Journal
Volume 10 Issue 2 Pages 178
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The leaf area, as an important leaf functional trait, is thought to be related to leaf length and width. Our recent study showed that the Montgomery equation, which assumes that leaf area is proportional to the product of leaf length and width, applied to different leaf shapes, and the coefficient of proportionality (namely the Montgomery parameter) range from 1/2 to π/4. However, no relevant geometrical evidence has previously been provided to support the above findings. Here, four types of representative leaf shapes (the elliptical, sectorial, linear, and triangular shapes) were studied. We derived the range of the estimate of the Montgomery parameter for every type. For the elliptical and triangular leaf shapes, the estimates are π/4 and 1/2, respectively; for the linear leaf shape, especially for the plants of Poaceae that can be described by the simplified Gielis equation, the estimate ranges from 0.6795 to π/4; for the sectorial leaf shape, the estimate ranges from 1/2 to π/4. The estimates based on the observations of actual leaves support the above theoretical results. The results obtained here show that the coefficient of proportionality of leaf area versus the product of leaf length and width only varies in a small range, maintaining the allometric relationship for leaf area and thereby suggesting that the proportional relationship between leaf area and the product of leaf length and width broadly remains stable during leaf evolution.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000460744000102 Publication Date 2019-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1999-4907 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:157200 Serial 8427
Permanent link to this record
 
 
Author Fougerolle, Y.D.; Truchetet, F.; Demonceaux, C.; Gielis, J.
Title A robust evolutionary algorithm for the recovery of rational Gielis curves Type (up) A1 Journal article
Year 2013 Publication Pattern recognition Abbreviated Journal
Volume 46 Issue 8 Pages 2078-2091
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Gielis curves (GC) can represent a wide range of shapes and patterns ranging from star shapes to symmetric and asymmetric polygons, and even self intersecting curves. Such patterns appear in natural objects or phenomena, such as flowers, crystals, pollen structures, animals, or even wave propagation. Gielis curves and surfaces are an extension of Lamé curves and surfaces (superquadrics) which have benefited in the last two decades of extensive researches to retrieve their parameters from various data types, such as range images, 2D and 3D point clouds, etc. Unfortunately, the most efficient techniques for superquadrics recovery, based on deterministic methods, cannot directly be adapted to Gielis curves. Indeed, the different nature of their parameters forbids the use of a unified gradient descent approach, which requires initial pre-processings, such as the symmetry detection, and a reliable pose and scale estimation. Furthermore, even the most recent algorithms in the literature remain extremely sensitive to initialization and often fall into local minima in the presence of large missing data. We present a simple evolutionary algorithm which overcomes most of these issues and unifies all of the required operations into a single though efficient approach. The key ideas in this paper are the replacement of the potential fields used for the cost function (closed form) by the shortest Euclidean distance (SED, iterative approach), the construction of cost functions which minimize the shortest distance as well as the curve length using R-functions, and slight modifications of the evolutionary operators. We show that the proposed cost function based on SED and R-function offers the best compromise in terms of accuracy, robustness to noise, and missing data.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000317944800002 Publication Date 2013-01-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-3203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:107181 Serial 8485
Permanent link to this record
 
 
Author Huang, W.; Su, X.; Ratkowsky, D.A.; Niklas, K.J.; Gielis, J.; Shi, P.
Title The scaling relationships of leaf biomass vs. leaf surface area of 12 bamboo species Type (up) A1 Journal article
Year 2019 Publication Global ecology and conservation Abbreviated Journal
Volume 20 Issue Pages e00793
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract There is convincing evidence for a scaling relationship between leaf dry weight (DW) and leaf surface area (A) for broad-leaved plants, and most estimates of the scaling exponent of DW vs. A are greater than unity. However, the scaling relationship of leaf fresh weight (FW) vs. A has been largely neglected. In the present study, we examined whether there is a statistically strong scaling relationship between FW and A and compared the goodness of fit to that of DW vs. A. Between 250 and 520 leaves from each of 12 bamboo species within 2 genera (Phyllostachys and Pleioblastus) were investigated. The reduced major axis regression protocols were used to determine scaling relationships. The fit for the linearized scaling relationship of FW vs. A was compared with that of DW vs. A using the coefficient of determination (i.e., r2). A stronger scaling relationship between FW and A than that between DW and A was observed for each of the 12 bamboo species investigated. Among the 12 species examined, five had significantly smaller scaling exponents of FW vs. A compared to those of DW vs. A; only one species had a scaling exponent of FW vs. A greater than that of DW vs. A. No significant difference between the two scaling exponents was observed for the remaining 6 species. Researchers conducting future studies might be well advised to consider the influence of leaf fresh weight when exploring the scaling relationships of foliar biomass allocation patterns.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000498226800095 Publication Date 2019-09-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2351-9894; 2351-9894 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:162954 Serial 8497
Permanent link to this record
 
 
Author Caratelli, D.; Gielis, J.; Tavkhelidze, I.; Ricci, P.E.
Title Spherical harmonic solution of the Robin problem for the Helmholtz equation in a supershaped shell Type (up) A1 Journal article
Year 2013 Publication Applied mathematics Abbreviated Journal
Volume 4 Issue 1a Pages 263-270
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The Robin problem for the Helmholtz equation in normal-polar shells is addressed by using a suitable spherical harmonic expansion technique. Attention is in particular focused on the wide class of domains whose boundaries are defined by a generalized version of the so-called superformula introduced by Gielis. A dedicated numerical procedure based on the computer algebra system Mathematica? is developed in order to validate the proposed methodology. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2013-01-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2152-7385 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:107177 Serial 8576
Permanent link to this record
 
 
Author Huang, W.; Li, Y.; Niklas, K.J.; Gielis, J.; Ding, Y.; Cao, L.; Shi, P.
Title A superellipse with deformation and its application in describing the cross-sectional shapes of a square bamboo Type (up) A1 Journal article
Year 2020 Publication Symmetry-Basel Abbreviated Journal Symmetry-Basel
Volume 12 Issue 12 Pages 2073
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Many cross-sectional shapes of plants have been found to approximate a superellipse rather than an ellipse. Square bamboos, belonging to the genus Chimonobambusa (Poaceae), are a group of plants with round-edged square-like culm cross sections. The initial application of superellipses to model these culm cross sections has focused on Chimonobambusa quadrangularis (Franceschi) Makino. However, there is a need for large scale empirical data to confirm this hypothesis. In this study, approximately 750 cross sections from 30 culms of C. utilis were scanned to obtain cross-sectional boundary coordinates. A superellipse exhibits a centrosymmetry, but in nature the cross sections of culms usually deviate from a standard circle, ellipse, or superellipse because of the influences of the environment and terrain, resulting in different bending and torsion forces during growth. Thus, more natural cross-sectional shapes appear to have the form of a deformed superellipse. The superellipse equation with a deformation parameter (SEDP) was used to fit boundary data. We find that the cross-sectional shapes (including outer and inner rings) of C. utilis can be well described by SEDP. The adjusted root-mean-square error of SEDP is smaller than that of the superellipse equation without a deformation parameter. A major finding is that the cross-sectional shapes can be divided into two types of superellipse curves: hyperellipses and hypoellipses, even for cross sections from the same culm. There are two proportional relationships between ring area and the product of ring length and width for both the outer and inner rings. The proportionality coefficients are significantly different, as a consequence of the two different superellipse types (i.e., hyperellipses and hypoellipses). The difference in the proportionality coefficients between hyperellipses and hypoellipses for outer rings is greater than that for inner rings. This work informs our understanding and quantifying of the longitudinal deformation of plant stems for future studies to assess the influences of the environment on stem development. This work is also informative for understanding the deviation of natural shapes from a strict rotational symmetry.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000602546300001 Publication Date 2020-12-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-8994 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.7 Times cited Open Access
Notes Approved Most recent IF: 2.7; 2020 IF: 1.457
Call Number UA @ admin @ c:irua:174472 Serial 8622
Permanent link to this record
 
 
Author Gielis, J.; Brasili, S.
Title The apeirogon and dual numbers Type (up) A1 Journal article
Year 2021 Publication Symmetry : culture and science Abbreviated Journal
Volume 32 Issue 2 Pages 157-160
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The richness, diversity, connection, depth and pleasure of studying symmetry continue to open doors. Here we report a connection between Coxeter's Apeirogon and the geometry associated with pictorial space, parabolic rotation and dual numbers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000670122100011 Publication Date 2021-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0865-4824 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:179759 Serial 8652
Permanent link to this record
 
 
Author Caratelli, D.; Gielis, J.; Natalini, P.; Ricci, P.E.; Tavkhelidze, I.
Title The Robin problem for the Helmholtz equation in a starlike planar domain Type (up) A1 Journal article
Year 2011 Publication Georgian mathematical journal Abbreviated Journal
Volume 18 Issue 3 Pages 465-479
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The interior and exterior Robin problems for the Helmholtz equation in starlike planar domains are addressed by using a suitable Fourier-like technique. Attention is in particular focused on normal-polar domains whose boundaries are defined by the so-called superformula introduced by J. Gielis. A dedicated numerical procedure based on the computer algebra system Mathematica© is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained. The computed results are found to be in good agreement with the theoretical findings on Fourier series expansion presented by L. Carleson.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000296166100004 Publication Date 2021-02-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1072-947x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:91086 Serial 8658
Permanent link to this record
 
 
Author Gielis, J.; Caratelli, D.; Fougerolle, Y.; Ricci, P.E.; Tavkelidze, I.; Gerats, T.
Title Universal natural shapes : from unifying shape description to simple methods for shape analysis and boundary value problems Type (up) A1 Journal article
Year 2012 Publication PLoS ONE Abbreviated Journal
Volume 7 Issue 9 Pages e29324-11
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Gielis curves and surfaces can describe a wide range of natural shapes and they have been used in various studies in biology and physics as descriptive tool. This has stimulated the generalization of widely used computational methods. Here we show that proper normalization of the Levenberg-Marquardt algorithm allows for efficient and robust reconstruction of Gielis curves, including self-intersecting and asymmetric curves, without increasing the overall complexity of the algorithm. Then, we show how complex curves of k-type can be constructed and how solutions to the Dirichlet problem for the Laplace equation on these complex domains can be derived using a semi-Fourier method. In all three methods, descriptive and computational power and efficiency is obtained in a surprisingly simple way.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000309517500001 Publication Date 2012-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:102202 Serial 8711
Permanent link to this record
 
 
Author Lin, S.; Shao, L.; Hui, C.; Song, Y.; Reddy, G.V.P.; Gielis, J.; Li, F.; Ding, Y.; Wei, Q.; Shi, P.; Reddy, G.V.P.
Title Why does not the leaf weight-area allometry of bamboos follow the 3/2-power law? Type (up) A1 Journal article
Year 2018 Publication Frontiers in plant science Abbreviated Journal
Volume 9 Issue Pages 583
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The principle of similarity (Thompson, 1917) states that the weight of an organism follows the 3/2-power law of its surface area and is proportional to its volume on the condition that the density is constant. However, the allometric relationship between leaf weight and leaf area has been reported to greatly deviate from the 3/2-power law, with the irregularity of leaf density largely ignored for explaining this deviation. Here, we choose 11 bamboo species to explore the allometric relationships among leaf area (A), density (ρ), length (L), thickness (T), and weight (W). Because the edge of a bamboo leaf follows a simplified two-parameter Gielis equation, we could show that A ∝ L2 and that A ∝ T2. This then allowed us to derive the density-thickness allometry ρ ∝ Tb and the weight-area allometry W ∝ A(b+3)/2 ≈ A9/8, where b approximates −3/4. Leaf density is strikingly negatively associated with leaf thickness, and it is this inverse relationship that results in the weight-area allometry to deviate from the 3/2-power law. In conclusion, although plants are prone to invest less dry mass and thus produce thinner leaves when the leaf area is sufficient for photosynthesis, such leaf thinning needs to be accompanied with elevated density to ensure structural stability. The findings provide the insights on the evolutionary clue about the biomass investment and output of photosynthetic organs of plants. Because of the importance of leaves, plants could have enhanced the ratio of dry material per unit area of leaf in order to increase the efficiency of photosynthesis, relative the other parts of plants. Although the conclusion is drawn only based on 11 bamboo species, it should also be applicable to the other plants, especially considering previous works on the exponent of the weight-area relationship being less than 3/2 in plants.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000431415100001 Publication Date 2018-05-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1664-462x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:150948 Serial 8758
Permanent link to this record
 
 
Author Shi, P.; Chen, L.; Quinn, B.K.; Yu, K.; Miao, Q.; Guo, X.; Lian, M.; Gielis, J.; Niklas, K.J.
Title A simple way to calculate the volume and surface area of avian eggs Type (up) A1 Journal article
Year 2023 Publication Annals of the New York Academy of Sciences Abbreviated Journal
Volume 1524 Issue 1 Pages 118-131
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Egg geometry can be described using Preston's equation, which has seldom been used to calculate egg volume (V) and surface area (S) to explore S versus V scaling relationships. Herein, we provide an explicit re-expression of Preston's equation (designated as EPE) to calculate V and S, assuming that an egg is a solid of revolution. The side (longitudinal) profiles of 2221 eggs of six avian species were digitized, and the EPE was used to describe each egg profile. The volumes of 486 eggs from two avian species predicted by the EPE were compared with those obtained using water displacement in graduated cylinders. There was no significant difference in V using the two methods, which verified the utility of the EPE and the hypothesis that eggs are solids of revolution. The data also indicated that V is proportional to the product of egg length (L) and maximum width (W) squared. A 2/3-power scaling relationship between S and V for each species was observed, that is, S is proportional to (LW2)(2/3). These results can be extended to describe the shapes of the eggs of other species to study the evolution of avian (and perhaps reptilian) eggs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000975679400001 Publication Date 2023-04-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0077-8923; 1749-6632 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.2 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.2; 2023 IF: 4.706
Call Number UA @ admin @ c:irua:196724 Serial 8827
Permanent link to this record
 
 
Author Wang, L.; Shi, P.; Chen, L.; Gielis, J.; Niklas, K.J.
Title Evidence that Chinese white olive (Canarium album(Lour.) DC.) fruits are solids of revolution Type (up) A1 Journal article
Year 2023 Publication Botany letters Abbreviated Journal
Volume Issue Pages 1-7
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Although many fruit geometries resemble a solid of revolution, this assumption has rarely been rigorously examined. To test this assumption, 574 fruits of Canarium album (Lour.) DC. which appear to have an ellipsoidal shape, were examined to determine the validity of a general avian-based egg-shape equation, referred to as the explicit Preston equation (EPE). The assumption that the C. album fruit geometry is a solid of revolution is tested by applying the volume formula for a solid of revolution using the EPE. The goodness of fit of the EPE was assessed using the adjusted root-mean-square error (RMSEadj). The relationship between the observed volume (Vobs) of each fruit, as measured by water displacement in a graduated cylinder, and the predicted volumes (Vpre) based on the EPE was also evaluated using the equation Vpre = slope * Vobs. All the RMSEadj values were smaller than 0.05, which demonstrated the validity of the EPE based on C. album fruit profiles. The 95% confidence interval of the slope of Vpre vs. Vobs included 1.0, indicating that there was no significant difference between Vpre and Vobs. The data confirm that C. album fruits are solids of revolution. This study provides a new approach for calculating the volume and surface area of geometrically similar fruits, which can be extended to other species with similar fruit geometries to further explore the ontogeny and evolution of angiosperm reproductive organs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001033135400001 Publication Date 2023-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2381-8107; 2381-8115 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.5 Times cited Open Access Not_Open_Access: Available from 24.01.2024
Notes Approved Most recent IF: 1.5; 2023 IF: NA
Call Number UA @ admin @ c:irua:198001 Serial 8864
Permanent link to this record
 
 
Author Lian, M.; Shi, P.; Zhang, L.; Yao, W.; Gielis, J.; Niklas, K.J.
Title A generalized performance equation and its application in measuring the Gini index of leaf size inequality Type (up) A1 Journal article
Year 2023 Publication Trees: structure and function Abbreviated Journal
Volume 37 Issue Pages 1555-1565
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The goal of this study is to provide a rigorous tool to quantify the inequality of the leaf size distribution of an individual plant, thereby serving as a reference trait for quantifying plant adaptations to local environmental conditions. The tool to be presented and tested employs three components: (1) a performance equation (PE), which can produce flexible asymmetrical and symmetrical bell-shaped curves, (2) the Lorenz curve (i.e., the cumulative proportion of leaf size vs. the cumulative proportion of number of leaves), which is the basis for calculating, and (3) the Gini index, which measures the inequality of leaf size distribution. We sampled 12 individual plants of a dwarf bamboo and measured the area and dry mass of each leaf of each plant. We then developed a generalized performance equation (GPE) of which the PE is a special case and fitted the Lorenz curve to leaf size distribution using the GPE and PE. The GPE performed better than the PE in fitting the Lorenz curve. We compared the Gini index of leaf area distribution with that of leaf dry mass distribution and found that there was a significant difference between the two indices that might emerge from the scaling relationship between leaf dry mass and area. Nevertheless, there was a strong correlation between the two Gini indices (r2 = 0.9846). This study provides a promising tool based on the GPE for quantifying the inequality of leaf size distributions across individual plants and can be used to quantify plant adaptations to local environmental conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001069570200001 Publication Date 2023-08-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0931-1890; 1432-2285 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.3 Times cited Open Access Not_Open_Access: Available from 26.02.2024
Notes Approved Most recent IF: 2.3; 2023 IF: 1.842
Call Number UA @ admin @ c:irua:199562 Serial 8874
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Author Huang, L.; Ratkowsky, D.A.; Hui, C.; Gielis, J.; Lian, M.; Shi, P.
Title Inequality measure of leaf area distribution for a drought-tolerant landscape plant Type (up) A1 Journal article
Year 2023 Publication Plants Abbreviated Journal
Volume 12 Issue 17 Pages 3143-11
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Measuring the inequality of leaf area distribution per plant (ILAD) can provide a useful tool for quantifying the influences of intra- and interspecific competition, foraging behavior of herbivores, and environmental stress on plants’ above-ground architectural structures and survival strategies. Despite its importance, there has been limited research on this issue. This paper aims to fill this gap by comparing four inequality indices to measure ILAD, using indices for quantifying household income that are commonly used in economics, including the Gini index (which is based on the Lorenz curve), the coefficient of variation, the Theil index, and the mean log deviation index. We measured the area of all leaves for 240 individual plants of the species Shibataea chinensis Nakai, a drought-tolerant landscape plant found in southern China. A three-parameter performance equation was fitted to observations of the cumulative proportion of leaf area vs. the cumulative proportion of leaves per plant to calculate the Gini index for each individual specimen of S. chinensis. The performance equation was demonstrated to be valid in describing the rotated and right shifted Lorenz curve, given that >96% of root-mean-square error values were smaller than 0.004 for 240 individual plants. By examining the correlation between any of the six possible pairs of indices among the Gini index, the coefficient of variation, the Theil index, and the mean log deviation index, the data show that these indices are closely related and can be used interchangeably to quantify ILAD.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001065193100001 Publication Date 2023-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2223-7747 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:199564 Serial 8886
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Author Gielis, J.
Title Simon Stevin as a central figure in the development of abstract algebra and generic programming Type (up) A1 Journal article
Year 2023 Publication Symmetry : culture and science Abbreviated Journal
Volume 34 Issue 2 Pages 155-168
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Simon Stevin (1548-1620) is mainly known for the decimal system and his Clootkrans proof. His influence is also profound in infinitesimal calculus, mechanics, and even in abstract algebra and today’s conception of polynomials, algorithms, and generic programming. Here we review his influence as assessed in generic programming. According to Dr. Stepanov, one of the most influential researchers in generic programming, Stevin’s work on polynomials can be regarded as the essence of generic programming: an algorithm from one domain can be applied in another similar domain.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001068714100003 Publication Date 2023-07-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0865-4824 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access Not_Open_Access: Available from 08.02.2024
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:198000 Serial 8929
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Author Li, Q.; Niklas, K.J.J.; Niinemets, U.; Zhang, L.; Yu, K.; Gielis, J.; Gao, J.; Shi, P.
Title Stomatal shape described by a superellipse in four Magnoliaceae species Type (up) A1 Journal article
Year 2023 Publication Botany letters Abbreviated Journal
Volume Issue Pages 1-9
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Stomata are essential for the exchange of water vapour and atmospheric gases between vascular plants and their external environments. The stomatal geometries of many plants appear to be elliptical. However, prior studies have not tested whether this is a mathematical reality, particularly since many natural shapes that appear to be ellipses are superellipses with greater or smaller edge curvature than predicted for an ellipse. Compared with the ellipse equation, the superellipse equation includes an additional parameter that allows generation of a larger range of shapes. We randomly selected 240 stomata from each of four Magnoliaceae species to test whether the stomatal geometries are superellipses or ellipses. The stomatal geometries for most stomata (943/960) were found to be described better using the superellipse equation. The traditional “elliptical stomata hypothesis” resulted in an underestimation of the area of stomata, whereas the superellipse equation accurately predicted stomatal area. This finding has important implications for the estimation of stomatal area in studies looking at stomatal shape, geometry, and function.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001024190300001 Publication Date 2023-07-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2381-8107; 2381-8115 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.5 Times cited Open Access Not_Open_Access: Available from 12.01.2024
Notes Approved Most recent IF: 1.5; 2023 IF: NA
Call Number UA @ admin @ c:irua:197847 Serial 8935
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Author Zhang, L.; Quinn, B.K.; Hui, C.; Lian, M.; Gielis, J.; Gao, J.; Shi, P.
Title New indices to balance α-diversity against tree size inequality Type (up) A1 Journal article
Year 2024 Publication Journal of forestry research Abbreviated Journal
Volume 35 Issue 1 Pages 31-39
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The number and composition of species in a community can be quantified with alpha-diversity indices, including species richness (R), Simpson's index (D), and the Shannon-Wiener index (HGREEK TONOS). In forest communities, there are large variations in tree size among species and individuals of the same species, which result in differences in ecological processes and ecosystem functions. However, tree size inequality (TSI) has been largely neglected in studies using the available diversity indices. The TSI in the diameter at breast height (DBH) data for each of 999 20 m x 20 m forest census quadrats was quantified using the Gini index (GI), a measure of the inequality of size distribution. The generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per quadrat. We also examined the relationships of alpha-diversity indices with the GI using correlation tests. The generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions, with most root-mean-square errors (990 out of 999 quadrats) being < 0.0030. There were significant positive correlations between each of three alpha-diversity indices (i.e., R, D, and H') and the GI. Nevertheless, the total abundance of trees in each quadrat did not significantly influence the GI. This means that the TSI increased with increasing species diversity. Thus, two new indices are proposed that can balance alpha-diversity against the extent of TSI in the community: (1 – GI) x D, and (1 – GI) x H'. These new indices were significantly correlated with the original D and HGREEK TONOS, and did not increase the extent of variation within each group of indices. This study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities, especially in the face of cumulative species loss under global climate change.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001131698000001 Publication Date 2023-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1007-662x; 1993-0607 ISBN Additional Links UA library record; WoS full record
Impact Factor 3 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 3; 2024 IF: 0.774
Call Number UA @ admin @ c:irua:201972 Serial 9061
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Author Yao, W.; Hui, C.; Wang, L.; Wang, J.; Gielis, J.; Shi, P.
Title Comparison of the performance of two polar equations in describing the geometries of elliptical fruits Type (up) A1 Journal article
Year 2024 Publication Botany letters Abbreviated Journal
Volume Issue Pages
Keywords A1 Journal article; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS)
Abstract In nature, the two-dimensional (2D) profiles of fruits from many plants often resemble ellipses. However, it remains unclear whether these profiles strictly adhere to the ellipse equation, as many natural shapes resembling ellipses are actually better described as superellipses. The superellipse equation, which includes an additional parameter n compared to the ellipse equation, can generate a broader range of shapes, with the ellipse being just a special case of the superellipse. To investigate whether the 2D profiles of fruits are better described by ellipses or superellipses, we collected a total of 751 mature and undamaged fruits from 31 naturally growing plants of Cucumis melo L. var. agrestis Naud. Our analysis revealed that most adjusted root-mean-square errors (> 92% of the 751 fruits) for fitting the superellipse equation to the fruit profiles were consistently less than 0.0165. Furthermore, there were 638 of the 751 fruits (ca. 85%) with the 95% confidence intervals of the estimated parameter n in the superellipse equation not including 2. These findings suggest that the profiles of C. melo var. agrestis fruits align more closely with the superellipse equation than with the ellipse equation. This study provides evidence for the existence of the superellipse in fruit profiles, which has significant implications for studying fruit geometries and estimating fruit volumes using the solid of revolution formula. Furthermore, this discovery may contribute to a deeper understanding of the mechanisms driving the evolution of fruit shapes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001219634500001 Publication Date 2024-05-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2381-8107; 2381-8115 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:205955 Serial 9140
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Author Gielis, J.; Tavkhelidze, I.; Ricci, P.E.
Title About “bulky” links generated by generalized Möbius-Listing bodies GML2n Type (up) A2 Journal article
Year 2013 Publication Journal of mathematical sciences Abbreviated Journal
Volume 193 Issue 3 Pages 449-460
Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In this paper, we consider the bulky knots and bulky links, which appear after cutting of a Generalized MöbiusListing GMLn2 body (with the radial cross section a convex plane 2-symmetric figure with two vertices) along a different Generalized MöbiusListing surfaces GMLn2 situated in it. The aim of this report is to investigate the number and geometric structure of the independent objects that appear after such a cutting process of GMLn2 bodies. In most cases we are able to count the indices of the resulting mathematical objects according to the known classification for the standard knots and links.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2013-08-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1072-3374; 1573-8795 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:110953 Serial 7404
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Author Gielis, J.
Title Er bestaan geen absurde, irrationele, onregelmatige of onderling niet-onmeetbare meetkundige getallen Type (up) A2 Journal article
Year 2021 Publication Wiskunde en onderwijs Abbreviated Journal
Volume 47 Issue 188 Pages 23-33
Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2032-0485 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:183083 Serial 7934
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Author Vermander, C.; De Wael, J.; Gielis, J.
Title De kleine boerderij : twee bijzondere tuinkamers Type (up) A2 Journal article
Year 2019 Publication Groencontact Abbreviated Journal
Volume 45 Issue 5 Pages 14-19
Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
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Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1374-4631 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:164895 Serial 8142
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Author Caratelli, D.; Gielis, J.; Ricci, P.E.; Tavkhelidze, I.
Title Some properties of “bulky” links, generated by Generalized Möbius Listing's bodies GML4n Type (up) A2 Journal article
Year 2016 Publication Journal of mathematical sciences Abbreviated Journal
Volume 216 Issue 4 Pages 509-518
Keywords A2 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In the present paper, we consider the bulky knots and bulky links that appear after cutting of generalized MöbiusListing GML 4 n bodies (with corresponding radial cross sections square) along different generalized MöbiusListing surfaces GML 2 n situated in it. The aim of this article is to examine the number and geometric structure of independent objects that appear after such a cutting process of GML 4 n bodies. In most cases, we are able to count the indices of the resulting mathematical objects according to the known tabulation for knots and links of small complexity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2016-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1072-3374; 1573-8795 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:133948 Serial 8554
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Author Gielis, J.; Grigolia, R.
Title Lamé curves and Rvachev's R-functions Type (up) A3 Journal article
Year 2022 Publication Sn – 1512-0066 Abbreviated Journal
Volume 37 Issue Pages 1-4
Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Gielis transformations are a generalization of Lame curves. To combine domains, we can make use of the natural alliance between Lame's work and Rvachev's R-functions. A logical next step is the extension to n-valued logic dening dierent partitions.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:189316 Serial 7178
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Author Tavkhelidze, I.; Gielis, J.; Pinelas, S.
Title About some methods of analytic representation and classification of a wide set of geometric figures with “complex” configuration Type (up) A3 Journal article
Year 2020 Publication Sn – 1512-0066 Abbreviated Journal
Volume 34 Issue Pages 81-84
Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:174475 Serial 7406
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Author Düking, R.; Gielis, J.; Liese, W.
Title Carbon flux and carbon stock in a bamboo stand and their relevance for mitigating climate change Type (up) A3 Journal article
Year 2011 Publication Bamboo Science & Culture Abbreviated Journal
Volume 24 Issue 1 Pages 1-6
Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In this report we describe the basics of biological carbon fixation in bamboo forests. Confusing carbon stock with carbon flux has led to false expectations on the significance of bamboo forests as carbon sinks. Furthermore, misunderstandings about the growth of bamboo culms can lead to highly exaggerated expectations on the productivity of bamboo.
Address
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Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1535-7635 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:91091 Serial 7578
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Author Gielis, J.; Tavkhelidze, I.
Title The Mӧbius phenomenon in Generalized Mӧbius-Listing bodies with cross sections of odd and even polygons Type (up) A3 Journal article
Year 2020 Publication Sn – 1512-0066 Abbreviated Journal
Volume 34 Issue Pages 23-26
Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:174474 Serial 8257
Permanent link to this record