Home << 1 2 3 4 >>
List View
 | 
Citations
 | 
Details
   web
Records
Author Gielis, J.; Shi, P.; Caratelli, D.
Title Universal equations : a fresh perspective Type A1 Journal article
Year 2022 Publication Growth and Form Abbreviated Journal
Volume Issue Pages (up)
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract A uniform description of natural shapes and phenomena is an important goal in science. Such description should check some basic principles, related to 1) the complexity of the model, 2) how well its fits real objects, phenomena and data, and 3) ia direct connection with optimization principles and the calculus of variations. In this article, we present nine principles, three for each group, and we compare some models with a claim to universality. It is also shown that Gielis Transformations and power laws have a common origin in conic sections
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:189317 Serial 7224
Permanent link to this record
 
 
Author Gielis, J.; Shi, P.; Beirinckx, B.; Caratelli, D.; Ricci, P.E.
Title Lamé-Gielis curves in biology and geometry Type P3 Proceeding
Year 2021 Publication Abbreviated Journal
Volume Issue Pages (up)
Keywords P3 Proceeding; 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:178828 Serial 8145
Permanent link to this record
 
 
Author Gielis, J.; Potters, G.
Title Proceedings of the 9th World Bamboo Congress, Antwerp 2012 Type P3 Proceeding
Year 2012 Publication Abbreviated Journal
Volume Issue Pages (up)
Keywords P3 Proceeding; Engineering sciences. Technology; 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 no
Call Number UA @ admin @ c:irua:97756 Serial 8413
Permanent link to this record
 
 
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 P3 Proceeding
Year 2013 Publication Abbreviated Journal
Volume Issue Pages (up)
Keywords P3 Proceeding; Engineering sciences. Technology; 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 no
Call Number UA @ admin @ c:irua:108672 Serial 8555
Permanent link to this record
 
 
Author Tavkhelidze, I.; Gielis, J.
Title Structure of the dm knives and process of cutting of GML(man) or GRT(man) bodies Type A3 Journal article
Year 2019 Publication Sn – 1512-0066 Abbreviated Journal
Volume 33 Issue Pages (up)
Keywords A3 Journal article; Engineering sciences. Technology; 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 no
Call Number UA @ admin @ c:irua:164897 Serial 8588
Permanent link to this record
 
 
Author Gielis, J.; Ding, Y.; Shi, P.
Title Towards a geometrical theory of morphology and morphogenesis Type P3 Proceeding
Year 2016 Publication Abbreviated Journal
Volume Issue Pages (up)
Keywords P3 Proceeding; Engineering sciences. Technology; 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 no
Call Number UA @ admin @ c:irua:144548 Serial 8677
Permanent link to this record
 
 
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 A1 Journal article
Year 2024 Publication Botany letters Abbreviated Journal
Volume Issue Pages (up)
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.
Address
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 1.5 Times cited Open Access
Notes Approved Most recent IF: 1.5; 2024 IF: NA
Call Number UA @ admin @ c:irua:205955 Serial 9140
Permanent link to this record
 
 
Author Gielis, J.; Caratelli, D.; Shi, P.; Ricci, P.E.
Title A note on spirals and curvature Type A1 Journal article
Year 2020 Publication Growth and form Abbreviated Journal
Volume 1 Issue 1 Pages (up) 1-8
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Starting from logarithmic, sinusoidal and power spirals, it is shown how these spirals are connected directly with Chebyshev polynomials, Lamé curves, with allometry and Antonelli-metrics in Finsler geometry. Curvature is a crucial concept in geometry both for closed curves and equiangular spirals, and allowed Dillen to give a general definition of spirals. Many natural shapes can be described as a combination of one of two basic shapes in nature—circle and spiral—with Gielis transformations. Using this idea, shape description itself is used to develop a novel approach to anisotropic curvature in nature. Various examples are discussed, including fusion in flowers and its connection to the recently described pseudo-Chebyshev functions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-02-23
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:167061 Serial 6569
Permanent link to this record
 
 
Author Li, Y.; Quinn, B.K.; Niinemets, Ü.; Schrader, J.; Gielis, J.; Liu, M.; Shi, P.
Title Ellipticalness index : a simple measure of the complexity of oval leaf shape Type A1 Journal article
Year 2022 Publication Pakistan journal of botany : An official publication of pakistan botanical society Abbreviated Journal Pak J Bot
Volume 54 Issue 6 Pages (up) 1-8
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Plants have diverse leaf shapes that have evolved to adapt to the environments they have experienced over their evolutionary history. Leaf shape and leaf size can greatly influence the growth rate, competitive ability, and productivity of plants. However, researchers have long struggled to decide how to properly quantify the complexity of leaf shape. Prior studies recommended the leaf roundness index (RI = 4πA/P2) or dissection index (DI = ), where P is leaf perimeter and A is leaf area. However, these two indices merely measure the extent of the deviation of leaf shape from a circle, which is usually invalid as leaves are seldom circular. In this study, we proposed a simple measure, named the ellipticalness index (EI), for quantifying the complexity of leaf shape based on the hypothesis that the shape of any oval leaf can be regarded as a variation from a standard ellipse. 2220 leaves from nine species of Magnoliaceae were sampled to check the validity of the EI. We also tested the validity of the Montgomery equation (ME), which assumes a proportional relationship between leaf area and the product of leaf length and width, because the EI actually comes from the proportionality coefficient of the ME. We also compared the ME with five other models of leaf area. The ME was found to be the best model for calculating leaf area based on consideration of the trade-off between model fit vs. complexity, which strongly supported the robustness of the EI for describing oval leaf shape. The new index can account for both leaf shape and size, and we conclude that it is a promising method for quantifying and comparing oval leaf shapes across species in future studies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000814279700028 Publication Date 2022-05-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0556-3321 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.2 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.2
Call Number UA @ admin @ c:irua:188469 Serial 7153
Permanent link to this record
 
 
Author De Tommasi, E.; Rogato, A.; Caratelli, D.; Mescia, L.; Gielis, J.
Title Following the photons route : mathematical models describing the interaction of diatoms with light Type H1 Book chapter
Year 2022 Publication Abbreviated Journal
Volume Issue Pages (up) 1-53
Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The interaction of diatoms with sunlight is fundamental in order to deeply understand their role in terrestrial ecology and biogeochemistry, essentially due to their massive contribution to global primary production through photosynthesis and its e↵ect on carbon, oxygen and silicon cycles. Following the journey of light through natural waters, its propagation through the intricate frustule micro- and nano-structure and, finally, its fate inside the photosynthetic machinery of the living cell requires several mathematical and computational models in order to accurately describe all the involved phenomena taking place at di↵erent space scales and physical regimes. In this chapter, we review the main analytical models describing the underwater optical field, the essential numerical algorithms for the study of photonic properties of the diatom frustule seen as a natural metamaterial, as well as the principal models describing photon harvesting in diatom plastids and methods for complex EM propagation problems and wave propagation in dispersive materials with multiple relaxation times. These mathematical methods will be integrated in a unifying geometric perspective.
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 978-1-119-74985-1 Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:186731 Serial 7165
Permanent link to this record
 
 
Author Gielis, J.; Grigolia, R.
Title Lamé curves and Rvachev's R-functions Type A3 Journal article
Year 2022 Publication Sn – 1512-0066 Abbreviated Journal
Volume 37 Issue Pages (up) 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.
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:189316 Serial 7178
Permanent link to this record
 
 
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 A3 Journal article
Year 2011 Publication Bamboo Science & Culture Abbreviated Journal
Volume 24 Issue 1 Pages (up) 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
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 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
Permanent link to this record
 
 
Author De Tommasi, E.; Gielis, J.; Rogato, A.
Title Diatom frustule morphogenesis and function : a multidisciplinary survey Type A1 Journal article
Year 2017 Publication Marine Genomics Abbreviated Journal
Volume 35 Issue Pages (up) 1-18
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Diatoms represent the major component of phytoplankton and are responsible for about 2025% of global primary production. Hundreds of millions of years of evolution led to tens of thousands of species differing in dimensions and morphologies. In particular, diatom porous silica cell walls, the frustules, are characterized by an extraordinary, species-specific diversity. It is of great interest, among the marine biologists and geneticists community, to shed light on the origin and evolutionary advantage of this variability of dimensions, geometries and pore distributions. In the present article the main reported data related to frustule morphogenesis and functionalities with contributions from fundamental biology, genetics, mathematics, geometry and physics are reviewed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000412957700001 Publication Date 2017-07-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1874-7787 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:144546 Serial 7807
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 A1 Journal article
Year 2014 Publication The teaching of mathematics Abbreviated Journal
Volume 17 Issue 1 Pages (up) 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 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 A1 Journal article
Year 2023 Publication Botany letters Abbreviated Journal
Volume Issue Pages (up) 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 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 A1 Journal article
Year 2023 Publication Botany letters Abbreviated Journal
Volume Issue Pages (up) 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
Permanent link to this record
 
 
Author Gielis, J.; Tavkhelidze, I.
Title The general case of cutting of Generalized Möbius-Listing surfaces and bodies Type A1 Journal article
Year 2020 Publication 4Open Abbreviated Journal
Volume 3 Issue Pages (up) 7-48
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The original motivation to study Generalized Möbius-Listing GML surfaces and bodies was the observation that the solution of boundary value problems greatly depends on the domains. Since around 2010 GML’s were merged with (continuous) Gielis Transformations, which provide a unifying description of geometrical shapes, as a generalization of the Pythagorean Theorem. The resulting geometrical objects can be used for modeling a wide range of natural shapes and phenomena. The cutting of GML bodies and surfaces, with the Möbius strip as one special case, is related to the field of knots and links, and classifications were obtained for GML with cross sectional symmetry of 2, 3, 4, 5 and 6. The general case of cutting GML bodies and surfaces, in particular the number of ways of cutting, could be solved by reducing the 3D problem to planar geometry. This also unveiled a range of connections with topology, combinatorics, elasticity theory and theoretical physics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2557-0250 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:174471 Serial 7992
Permanent link to this record
 
 
Author Tavkhelidze, I.; Cassisa, C.; Gielis, J.; Ricci, P.E.
Title About “bulky” links, generated by generalized Möbius Listing's bodies GML3n Type A1 Journal article
Year 2013 Publication Matematica e applicazioni : atti della Accademia nazionale dei Lincei Abbreviated Journal
Volume 24 Issue 1 Pages (up) 11-38
Keywords A1 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'', which appear after cutting a Generalized Möbius Listing's GMLn3 body (whose radial cross section is a plane 3-symmetric figure with three vertices) along different Generalized Möbius Listing's surfaces GMLn2 situated in it. This article is aimed to investigate the number and geometric structure of the independent objects appearing after such a cutting process of GMLn3 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 000316567700002 Publication Date 2013-03-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1120-6357 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:107174 Serial 7405
Permanent link to this record
 
 
Author Vermander, C.; De Wael, J.; Gielis, J.
Title De kleine boerderij : twee bijzondere tuinkamers Type A2 Journal article
Year 2019 Publication Groencontact Abbreviated Journal
Volume 45 Issue 5 Pages (up) 14-19
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 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
Permanent link to this record
 
 
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 A1 Journal article
Year 2021 Publication Advanced Studies : Euro-Tbilisi Mathematical Journal Abbreviated Journal
Volume 14 Issue 4 Pages (up) 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.
Address
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 Nicolau, F.; Gielis, J.; Simeone, A.L.; Simoes Lopes, D.
Title Exploring and selecting supershapes in virtual reality with line, quad, and cube shaped widgets Type P1 Proceeding
Year 2022 Publication Abbreviated Journal
Volume Issue Pages (up) 21-28
Keywords P1 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Supershapes are used in Parametric Design to model, literally, thou-sands of natural and man-made shapes with a single 6 parameter formula. However, users are left to probe such a rich yet dense collection of supershapes using a set of independent 1-D sliders. Some of the formula’s parameters are non-linear in nature, making them particularly difficult to grasp with conventional 1-D sliders alone. VR appears as a promising setting for Parametric Design with supershapes since it empowers users with more natural visual inspection and shape browsing techniques, with multiple solutions being displayed at once and the possibility to design more interesting forms of slider interaction. In this work, we propose VR shape widgets that allow users to probe and select supershapes from a multitude of solutions. Our designs take leverage on thumbnails, mini-maps, haptic feedback and spatial interaction, while supporting 1-D, 2-D and 3-D supershape parameter spaces. We conducted a user study (N = 18) and found that VR shape widgets are effective, more efficient, and natural than conventional VR 1-D sliders while also usable for users without prior knowledge on supershapes. We also found that the proposed VR widgets provide a quick overview of the main supershapes, and users can easily reach the desired solution without having to perform fine-grain handle manipulations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000828657500003 Publication Date 2022-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-6654-9617-9 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:188471 Serial 7161
Permanent link to this record
 
 
Author Li, Y.; Quinn, B.K.; Gielis, J.; Li, Y.; Shi, P.
Title Evidence that supertriangles exist in nature from the vertical projections of Koelreuteria paniculata fruit Type A1 Journal article
Year 2022 Publication Symmetry Abbreviated Journal Symmetry-Basel
Volume 14 Issue 1 Pages (up) 23
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Many natural radial symmetrical shapes (e.g., sea stars) follow the Gielis equation (GE) or its twin equation (TGE). A supertriangle (three triangles arranged around a central polygon) represents such a shape, but no study has tested whether natural shapes can be represented as/are supertriangles or whether the GE or TGE can describe their shape. We collected 100 pieces of Koelreuteria paniculata fruit, which have a supertriangular shape, extracted the boundary coordinates for their vertical projections, and then fitted them with the GE and TGE. The adjusted root mean square errors (RMSEadj) of the two equations were always less than 0.08, and >70% were less than 0.05. For 57/100 fruit projections, the GE had a lower RMSEadj than the TGE, although overall differences in the goodness of fit were non-significant. However, the TGE produces more symmetrical shapes than the GE as the two parameters controlling the extent of symmetry in it are approximately equal. This work demonstrates that natural supertriangles exist, validates the use of the GE and TGE to model their shapes, and suggests that different complex radially symmetrical shapes can be generated by the same equation, implying that different types of biological symmetry may result from the same biophysical mechanisms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000746030100001 Publication Date 2021-12-27
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 OpenAccess
Notes Approved Most recent IF: 2.7
Call Number UA @ admin @ c:irua:186453 Serial 7158
Permanent link to this record
 
 
Author Gielis, J.
Title Er bestaan geen absurde, irrationele, onregelmatige of onderling niet-onmeetbare meetkundige getallen Type A2 Journal article
Year 2021 Publication Wiskunde en onderwijs Abbreviated Journal
Volume 47 Issue 188 Pages (up) 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
Permanent link to this record
 
 
Author Gielis, J.; Tavkhelidze, I.
Title The Mӧbius phenomenon in Generalized Mӧbius-Listing bodies with cross sections of odd and even polygons Type A3 Journal article
Year 2020 Publication Sn – 1512-0066 Abbreviated Journal
Volume 34 Issue Pages (up) 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
 
 
Author Gielis, J.
Title Phi-bonacci in Ancient Greece Type A1 Journal article
Year 2021 Publication Symmetry : culture and science Abbreviated Journal
Volume 32 Issue 1 Pages (up) 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 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 A1 Journal article
Year 2024 Publication Journal of forestry research Abbreviated Journal
Volume 35 Issue 1 Pages (up) 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
Permanent link to this record
 
 
Author Gielis, J.; Tavkhelidze, I.
Title A note on Generalized Möbius-Listing Bodies Type P1 Proceeding
Year 2023 Publication Abbreviated Journal
Volume Issue Pages (up) 31-39 T2 - Proceedings of the 1st International Sy
Keywords P1 Proceeding; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Generalized Möbius-Listing surfaces and bodies generalize Möbius bands, and this research was 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. These conditions are based on congruence and rotational symmetry of the resulting cross sections after cutting, and on the knife cutting the origin
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2023-11-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-90-833839-0-3 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:201047 Serial 9063
Permanent link to this record
 
 
Author Shi, P.; Gielis, J.; Niklas, K.J.
Title Comparison of a universal (but complex) model for avian egg shape with a simpler model Type Editorial
Year 2022 Publication Annals of the New York Academy of Sciences Abbreviated Journal Ann Ny Acad Sci
Volume 1514 Issue 1 Pages (up) 34-42
Keywords Editorial; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Recently, a universal equation by Narushin, Romanov, and Griffin (hereafter, the NRGE) was proposed to describe the shape of avian eggs. While NRGE can simulate the shape of spherical, ellipsoidal, ovoidal, and pyriform eggs, its predictions were not tested against actual data. Here, we tested the validity of the NRGE by fitting actual data of egg shapes and compared this with the predictions of our simpler model for egg shape (hereafter, the SGE). The eggs of nine bird species were sampled for this purpose. NRGE was found to fit the empirical data of egg shape well, but it did not define the egg length axis (i.e., the rotational symmetric axis), which significantly affected the prediction accuracy. The egg length axis under the NRGE is defined as the maximum distance between two points on the scanned perimeter of the egg's shape. In contrast, the SGE fitted the empirical data better, and had a smaller root-mean-square error than the NRGE for each of the nine eggs. Based on its mathematical simplicity and goodness-of-fit, the SGE appears to be a reliable and useful model for describing egg shape.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000803394100001 Publication Date 2022-06-01
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
Call Number UA @ admin @ c:irua:188470 Serial 7139
Permanent link to this record
 
 
Author Dattoli, G.; Di Palma, E.; Gielis, J.; Licciardi, S.
Title Parabolic trigonometry Type A1 Journal article
Year 2020 Publication International journal of applied and computational mathematics Abbreviated Journal
Volume 6 Issue 2 Pages (up) 37
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-03-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2349-5103 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:167049 Serial 6578
Permanent link to this record
 
 
Author Mescia, L.; Chiapperino, M.A.; Bia, P.; Lamacchia, C.M.; Gielis, J.; Caratelli, D.
Title Design of electroporation process in irregularly shaped multicellular systems Type A1 Journal article
Year 2019 Publication Electronics (Basel) Abbreviated Journal
Volume 8 Issue 1 Pages (up) 37
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Electroporation technique is widely used in biotechnology and medicine for the transport of various molecules through the membranes of biological cells. Different mathematical models of electroporation have been proposed in the literature to study pore formation in plasma and nuclear membranes. These studies are mainly based on models using a single isolated cell with a canonical shape. In this work, a spacetime (x,y,t) multiphysics model based on quasi-static Maxwells equations and nonlinear Smoluchowskis equation has been developed to investigate the electroporation phenomenon induced by pulsed electric field in multicellular systems having irregularly shape. The dielectric dispersion of the cell compartments such as nuclear and plasmatic membranes, cytoplasm, nucleoplasm and external medium have been incorporated into the numerical algorithm, too. Moreover, the irregular cell shapes have been modeled by using the Gielis transformations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000457142800037 Publication Date 2019-01-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2079-9292 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:157203 Serial 7765
Permanent link to this record