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Author Gielis, J.; Caratelli, D.; Fougerolle, Y.; Ricci, P.E.; Tavkelidze, I.; Gerats, T. url  doi
openurl 
  Title Universal natural shapes : from unifying shape description to simple methods for shape analysis and boundary value problems Type 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.  
  Address  
  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 (up) UA @ admin @ c:irua:102202 Serial 8711  
Permanent link to this record
 

 
Author Tavkhelidze, I.; Cassisa, C.; Gielis, J.; Ricci, P.E. pdf  doi
openurl 
  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 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 (up) UA @ admin @ c:irua:107174 Serial 7405  
Permanent link to this record
 

 
Author Caratelli, D.; Gielis, J.; Tavkhelidze, I.; Ricci, P.E. url  doi
openurl 
  Title Spherical harmonic solution of the Robin problem for the Helmholtz equation in a supershaped shell Type 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 (up) UA @ admin @ c:irua:107177 Serial 8576  
Permanent link to this record
 

 
Author Fougerolle, Y.D.; Truchetet, F.; Demonceaux, C.; Gielis, J. pdf  doi
openurl 
  Title A robust evolutionary algorithm for the recovery of rational Gielis curves Type 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.  
  Address  
  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 (up) UA @ admin @ c:irua:107181 Serial 8485  
Permanent link to this record
 

 
Author Caratelli, D.; Gielis, J.; Tavkhelidze, I.; Ricci, P.E. url  doi
openurl 
  Title The Dirichlet problem for the Laplace equation in supershaped annuli Type A1 Journal article
  Year 2013 Publication Boundary value problems Abbreviated Journal  
  Volume Issue Pages 113-10  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The Dirichlet problem for the Laplace equation in normal-polar annuli is addressed by using a suitable Fourier-like technique. Attention is in particular focused on the wide class of domains whose boundaries are defined by 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 000325760900002&DestLinkType=CitingArticles&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7 Publication Date 2013-05-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1687-2762; 1687-2770 ISBN Additional Links UA library record; WoS citing articles; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:108644 Serial 7812  
Permanent link to this record
 

 
Author Caratelli, D.; Gielis, J.; Ricci, P.E.; Tavkhelidze, I. openurl 
  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  
  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 (up) UA @ admin @ c:irua:108672 Serial 8555  
Permanent link to this record
 

 
Author Gielis, J.; Tavkhelidze, I.; Ricci, P.E. pdf  doi
openurl 
  Title About “bulky” links generated by generalized Möbius-Listing bodies GML2n Type 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 (up) UA @ admin @ c:irua:110953 Serial 7404  
Permanent link to this record
 

 
Author Bia, P.; Caratelli, D.; Mescia, L.; Gielis, J. isbn  openurl
  Title Electromagnetic characterization of supershaped lens antennas for high-frequency applications Type H1 Book chapter
  Year 2013 Publication Abbreviated Journal  
  Volume Issue Pages 1679-1682 T2 - Proceedings of the 43rd European Mi  
  Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000330768700424 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-2-87487-031-6 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:110954 Serial 7865  
Permanent link to this record
 

 
Author Gielis, J.; Caratelli, D.; Tavkelidze, I.; Fougerolle, Y.; Ricci, P.E.; Gerats, T. isbn  openurl
  Title Bulky knots and links generated by cutting generalized Mobius-Listing bodies and applications in the natural sciences Type H2 Book chapter
  Year 2013 Publication Abbreviated Journal  
  Volume Issue Pages 167-183 T2 - Math Art Summit : Koninklijke Vlaamse  
  Keywords H2 Book chapter; 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 978-90-6569-119-4 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:110955 Serial 7569  
Permanent link to this record
 

 
Author Caratelli, D.; Gielis, J.; Tavkhelidze, I.; Ricci, P.E. url  doi
openurl 
  Title Fourier-Hankel solution of the Robin problem for the Helmholtz equation in supershaped annular domains Type A1 Journal article
  Year 2013 Publication Boundary value problems Abbreviated Journal  
  Volume Issue Pages 253  
  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 annuli is addressed by using a suitable Fourier-Hankel series technique. Attention is in particular focused on the wide class of domains whose boundaries are defined by 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 000340237600004 Publication Date 2013-11-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1687-2762; 1687-2770 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:111558 Serial 7981  
Permanent link to this record
 

 
Author Bia, P.; Caratelli, D.; Mescia, L.; Gielis, J. pdf  url
doi  openurl
  Title Analysis and synthesis of supershaped dielectric lens antennas Type A1 Journal article
  Year 2015 Publication IET microwaves, antennas and propagation Abbreviated Journal  
  Volume 9 Issue 14 Pages 1497-1504  
  Keywords A1 Journal article; Engineering sciences. Technology; Mass communications; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract A novel class of supershaped dielectric lens antennas, whose geometry is described by the three-dimensional (3D) Gielis formula, is introduced and analysed. To this end, a hybrid modelling approach based on geometrical and physical optics is adopted in order to efficiently analyse the multiple wave reflections occurring within the lens and to evaluate the relevant impact on the radiation properties of the antenna under analysis. The developed modelling procedure has been validated by comparison with numerical results already reported in the literature and, afterwards, applied to the electromagnetic characterisation of Gielis dielectric lens antennas with shaped radiation pattern. Furthermore, a dedicated optimisation algorithm based on quantum particle swarm optimisation has been developed for the synthesis of 3D supershaped lens antennas with single feed, as well as with beamforming capabilities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000364491200002 Publication Date 2015-08-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1751-8725 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:128659 Serial 7441  
Permanent link to this record
 

 
Author Gielis, J.; Verhulst, R.; Caratelli, D.; Ricci, P.E.; Tavkhelidze, I. url  openurl
  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 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 (up) UA @ admin @ c:irua:128660 Serial 8327  
Permanent link to this record
 

 
Author Shi, P.-J.; Xu, Q.; Sandhu, H.S.; Gielis, J.; Ding, Y.-L.; Li, H.-R.; Dong, X.-B. url  doi
openurl 
  Title Comparison of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship between spatial density of plants and total leaf area per plant Type A1 Journal article
  Year 2015 Publication Ecology and evolution Abbreviated Journal  
  Volume 5 Issue 20 Pages 4578-4589  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The relationship between spatial density and size of plants is an important topic in plant ecology. The self-thinning rule suggests a −3/2 power between average biomass and density or a −1/2 power between stand yield and density. However, the self-thinning rule based on total leaf area per plant and density of plants has been neglected presumably because of the lack of a method that can accurately estimate the total leaf area per plant. We aimed to find the relationship between spatial density of plants and total leaf area per plant. We also attempted to provide a novel model for accurately describing the leaf shape of bamboos. We proposed a simplified Gielis equation with only two parameters to describe the leaf shape of bamboos one model parameter represented the overall ratio of leaf width to leaf length. Using this method, we compared some leaf parameters (leaf shape, number of leaves per plant, ratio of total leaf weight to aboveground weight per plant, and total leaf area per plant) of four bamboo species of genus Indocalamus Nakai (I. pedalis (Keng) P.C. Keng, I. pumilus Q.H. Dai and C.F. Keng, I. barbatus McClure, and I. victorialis P.C. Keng). We also explored the possible correlation between spatial density and total leaf area per plant using log-linear regression. We found that the simplified Gielis equation fit the leaf shape of four bamboo species very well. Although all these four species belonged to the same genus, there were still significant differences in leaf shape. Significant differences also existed in leaf area per plant, ratio of leaf weight to aboveground weight per plant, and leaf length. In addition, we found that the total leaf area per plant decreased with increased spatial density. Therefore, we directly demonstrated the self-thinning rule to improve light interception.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000363731500008 Publication Date 2015-09-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-7758 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:128662 Serial 7691  
Permanent link to this record
 

 
Author Mescia, L.; Bia, P.; Caratelli, D.; Chiapperino, M.A.; Stukach, O.; Gielis, J. url  doi
openurl 
  Title Electromagnetic mathematical modeling of 3D supershaped dielectric lens antennas Type A1 Journal article
  Year 2016 Publication Mathematical problems in engineering: theory, methods, and applications Abbreviated Journal  
  Volume Issue Pages 8130160-10  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The electromagnetic analysis of a special class of 3D dielectric lens antennas is described in detail. This new class of lens antennas has a geometrical shape defined by the three-dimensional extension of Gielis formula. The analytical description of the lens shape allows the development of a dedicated semianalytical hybrid modeling approach based on geometrical tube tracing and physical optic. In order to increase the accuracy of the model, the multiple reflections occurring within the lens are also taken into account.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000372246600001 Publication Date 2016-02-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1024-123x; 1563-5147 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:131516 Serial 7866  
Permanent link to this record
 

 
Author Caratelli, D.; Gielis, J.; Ricci, P.E.; Tavkhelidze, I. pdf  doi
openurl 
  Title Some properties of “bulky” links, generated by Generalized Möbius Listing's bodies GML4n Type 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 (up) UA @ admin @ c:irua:133948 Serial 8554  
Permanent link to this record
 

 
Author De Tommasi, E.; Gielis, J.; Rogato, A. pdf  url
doi  openurl
  Title Diatom frustule morphogenesis and function : a multidisciplinary survey Type A1 Journal article
  Year 2017 Publication Marine Genomics Abbreviated Journal  
  Volume 35 Issue Pages 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 (up) UA @ admin @ c:irua:144546 Serial 7807  
Permanent link to this record
 

 
Author Lin, S.; Zhang, L.; Reddy, G.V.P.; Hui, C.; Gielis, J.; Ding, Y.; Shi, P. url  doi
openurl 
  Title A geometrical model for testing bilateral symmetry of bamboo leaf with a simplified Gielis equation Type A1 Journal article
  Year 2016 Publication Ecology and evolution Abbreviated Journal  
  Volume 6 Issue 19 Pages 6798-6806  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The size and shape of plant leaves change with growth, and an accurate description of leaf shape is crucial for describing plant morphogenesis and development. Bilateral symmetry, which has been widely observed but poorly examined, occurs in both dicot and monocot leaves, including all nominated bamboo species (approximately 1,300 species), of which at least 500 are found in China. Although there are apparent differences in leaf size among bamboo species due to genetic and environmental profiles, bamboo leaves have bilateral symmetry with parallel venation and appear similar across species. Here, we investigate whether the shape of bamboo leaves can be accurately described by a simplified Gielis equation, which consists of only two parameters (leaf length and shape) and produces a perfect bilateral shape. To test the applicability of this equation and the occurrence of bilateral symmetry, we first measured the leaf length of 42 bamboo species, examining >500 leaves per species. We then scanned 30 leaves per species that had approximately the same length as the median leaf length for that species. The leaf-shape data from scanned profiles were fitted to the simplified Gielis equation. Results confirmed that the equation fits the leaf-shape data extremely well, with the coefficients of determination being 0.995 on average. We further demonstrated the bilateral symmetry of bamboo leaves, with a clearly defined leaf-shape parameter of all 42 bamboo species investigated ranging from 0.02 to 0.1. This results in a simple and reliable tool for precise determination of bamboo species, with applications in forestry, ecology, and taxonomy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000385626100003 Publication Date 2016-09-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-7758 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:144547 Serial 7998  
Permanent link to this record
 

 
Author Gielis, J.; Ding, Y.; Shi, P. pdf  openurl
  Title Towards a geometrical theory of morphology and morphogenesis Type P3 Proceeding
  Year 2016 Publication Abbreviated Journal  
  Volume Issue Pages  
  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 (up) UA @ admin @ c:irua:144548 Serial 8677  
Permanent link to this record
 

 
Author Gielis, J.; Natalini, P.; Ricci, P.E. doi  isbn
openurl 
  Title A note about generalized forms of the Gielis formula Type H1 Book chapter
  Year 2017 Publication Abbreviated Journal  
  Volume 2 Issue Pages 107-116 T2 - Modeling in mathematics : proceedings  
  Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract We generalize the Gielis Superformula by extending the R. Chacon approach, but avoiding the use of Jacobi elliptic functions. The obtained results are extended to the three-dimensional case. Several new shapes are derived by using the computer algebra system Mathematica(C).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000442076400008 Publication Date 2017-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-94-6239-260-1; 978-94-6239-261-8; 2543-0300; 978-94-6239-260-1 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:144550 Serial 8318  
Permanent link to this record
 

 
Author Gielis, J.; Caratelli, D.; Fougerolle, Y.; Ricci, P.E.; Gerats, T. doi  isbn
openurl 
  Title A biogeometrical model for corolla fusion in Asclepiad flowers Type H1 Book chapter
  Year 2017 Publication Abbreviated Journal  
  Volume 2 Issue Pages 83-105 T2 - Modeling in mathematics : proceedings  
  Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The molecular genetics of flower development have been studied extensively for more than two decades. Fusion of organs and the tendency to oligomery, important characteristics of flower evolution, so far have remained fairly elusive. We present a geometric model for shape and fusion in the corolla of Asclepiads. Examples demonstrate how fusion of petals creates stable centers, a prerequisite for the formation of complex pollination structures via congenital and postgenital fusion events, with the formation of de novo organs, specific to Asclepiads. The development of the corolla reduces to simple inequalities from the MATHS-BOX. The formation of stable centers and of bell and tubular shapes in flowers are immediate and logical consequences of the shape. Our model shows that any study on flowers, especially in evo-devo perspective should be performed within the wider framework of polymery and oligomery and of fusion and synorganization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000442076400007 Publication Date 2017-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-94-6239-260-1; 978-94-6239-261-8; 2543-0300; 978-94-6239-260-1 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:144551 Serial 7561  
Permanent link to this record
 

 
Author Tavkhelidze, I.; Caratelli, D.; Gielis, J.; Ricci, P.E.; Rogava, M.; Transirico, M. doi  isbn
openurl 
  Title On a geometric model of bodies with “complex” configuration and some movements Type H1 Book chapter
  Year 2017 Publication Abbreviated Journal  
  Volume 2 Issue Pages 129-158 T2 - Modeling in mathematics : proceedings  
  Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Aim of this chapter is analytical representation of one wide class of geometric figures (lines, surfaces and bodies) and their complicated displacements. The accurate estimation of physical characteristics (such as volume, surface area, length, or other specific parameters) relevant to human organs is of fundamental importance in medicine. One central idea of this article is, in this respect, to provide a general methodology for the evaluation, as a function of time, of the volume and center of gravity featured by moving of one class of bodies used of describe different human organs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000442076400010 Publication Date 2017-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-94-6239-260-1; 978-94-6239-261-8; 2543-0300; 978-94-6239-260-1 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:144552 Serial 8326  
Permanent link to this record
 

 
Author Gielis, J.; Ricci, P.E.; Tavkhelidze, I. doi  isbn
openurl 
  Title Modeling in mathematics : proceedings of the second Tbilisi-Salerno workshop on modeling in mathematics Type ME3 Book as editor
  Year 2017 Publication Abbreviated Journal  
  Volume Issue Pages 185 p.  
  Keywords ME3 Book as editor; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2017-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-94-6239-260-1; 978-94-6239-261-8 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:144553 Serial 8263  
Permanent link to this record
 

 
Author Gielis, J. doi  isbn
openurl 
  Title The geometrical beauty of plants Type MA3 Book as author
  Year 2017 Publication Abbreviated Journal  
  Volume Issue Pages 229 p.  
  Keywords MA3 Book as author; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2017-06-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-94-6239-150-5; 978-94-6239-151-2 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:144554 Serial 7997  
Permanent link to this record
 

 
Author Mescia, L.; Chiapperino, M.A.; Bia, P.; Gielis, J.; Caratelli, D. pdf  doi
openurl 
  Title Modeling of electroporation induced by pulsed electric fields in irregularly shaped cells Type 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.  
  Address  
  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 (up) UA @ admin @ c:irua:148417 Serial 8264  
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Author de Jong van Coevorden, C.M.; Gielis, J.; Caratelli, D. url  doi
openurl 
  Title Application of Gielis transformation to the design of metamaterial structures Type A1 Journal article
  Year 2018 Publication Journal of physics : conference series Abbreviated Journal  
  Volume 963 Issue Pages Unsp 012008  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In this communication, the use of Gielis transformation to design more compact metamaterial unit cells is explored. For this purpose, transformed complementary split ring resonators and spiral resonators are coupled to micro-strip lines and theirbehaviour is investigated. The obtained results confirm that the useof the considered class of supershaped geometries enables the synthesis of very compact scalable microwave components.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000435022800008 Publication Date 2018-02-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588; 1742-6596 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:150947 Serial 7475  
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. url  doi
openurl 
  Title Why does not the leaf weight-area allometry of bamboos follow the 3/2-power law? Type 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 (up) UA @ admin @ c:irua:150948 Serial 8758  
Permanent link to this record
 

 
Author Gielis, J.; Caratelli, D.; de Jong van Coevorden, M.; Ricci, P.E. doi  isbn
openurl 
  Title The common descent of biological shape description and special functions Type H1 Book chapter
  Year 2018 Publication Abbreviated Journal  
  Volume 230 Issue Pages 119-131 T2 - Differential and difference equations  
  Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Gielis transformations, with their origin in botany, are used to define square waves and trigonometric functions of higher order. They are rewritten in terms of Chebyshev polynomials. The origin of both, a uniform descriptor and the origin of orthogonal polynomials, can be traced back to a letter of Guido Grandi to Leibniz in 1713 on the mathematical description of the shape of flowers. In this way geometrical description and analytical tools are seamlessly combined.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000451375900010 Publication Date 2018-05-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-3-319-75646-2; 2194-1009; 978-3-319-75647-9; 978-3-319-75646-2 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:150949 Serial 7685  
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Author Fougerolle, Y.; Truchetet, F.; Gielis, J. pdf  doi
openurl 
  Title Potential fields of self intersecting Gielis curves for modeling and generalized blending techniques Type P1 Proceeding
  Year 2017 Publication Modeling In Mathematics Abbreviated Journal  
  Volume 2 Issue Pages 67-81 T2 -  
  Keywords P1 Proceeding; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The definition of Gielis curves allows for the representation of self intersecting curves. The analysis and the understanding of these representations is of major interest for the analytical representation of sectors bounded by multiple subsets of curves (or surfaces), as this occurs for instance in many natural objects. We present a construction scheme based on R-functions to build signed potential fields with guaranteed differential properties, such that their zero-set corresponds to the outer, the inner envelop, or combined subparts of the curve. Our framework is designed to allow for the definition of composed domains built upon Boolean operations between several distinct objects or some subpart of self-intersecting curves, but also provides a representation for soft blending techniques in which the traditional Boolean union and intersection become special cases of linear combinations between the objects' potential fields. Finally, by establishing a connection between R-functions and Lame curves, we can extend the domain of the p parameter within the R-p-function from the set of the even positive numbers to the real numbers strictly greater than 1, i.e. p is an element of]1, +infinity[.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000442076400006 Publication Date 2017-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 978-94-6239-261-8; 978-94-6239-260-1; 978-94-6239-260-1 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:153801 Serial 8395  
Permanent link to this record
 

 
Author Tian, F.; Wang, Y.; Sandhu, H.S.; Gielis, J.; Shi, P. pdf  url
doi  openurl
  Title Comparison of seed morphology of two ginkgo cultivars Type A1 Journal article
  Year 2020 Publication Journal Of Forestry Research Abbreviated Journal J Forestry Res  
  Volume 31 Issue 3 Pages 751-758  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Ginkgo biloba L. is a precious relic tree species with important economic value. Seeds, as a vital reproductive organ of plants, can be used to distinguish cultivars of the species. We chose 400 seeds from two cultivars of ginkgo (Fozhi and Maling; 200 seeds for each cultivar) as the study material and used the Gielis equation to fit the projected shape of these seeds. The coefficients of variation (CV) in root mean squared errors (RMSE) obtained from the fitted data were used to compare the level of inter-cultivar variations in seed shape. We also used the covariance analysis to compare the allometric relationships between seed weights and projected areas of these two cultivars. The Gielis equation fitted well the seed shapes of two ginkgo cultivars. The lower CV in RMSE of cultivar Fozhi than Maling indicated a less symmetrical seed shape in the latter than the former. The bootstrap percentile method showed that the seed shape differences between the two cultivars were significant. However, there was no significant difference in the exponents between the seed weights and the projected areas of these two cultivars. Overall, the significant differences in shapes between the seeds of two ginkgo cultivars were well explained by the Gielis equation; this model can be further extended to compare morphological differences in other ginkgo cultivars, and even for plant seeds or animal eggs that have similar oval shapes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000529367600005 Publication Date 2018-07-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1007-662x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3 Times cited 3 Open Access  
  Notes ; ; Approved Most recent IF: 3; 2020 IF: 0.774  
  Call Number (up) UA @ admin @ c:irua:154987 Serial 6474  
Permanent link to this record
 

 
Author Martínez-Dueñas, E.J.R.; de Jong van Coevorden, C.M.; Stukach, O.V.; Panokin, N.V.; Gielis, J.; Caratelli, D. url  doi
openurl 
  Title Electromagnetic modeling and design of a novel class of complementary split‐ring resonators Type A1 Journal article
  Year 2019 Publication International journal of RF and microwave computer-aided engineering Abbreviated Journal  
  Volume 29 Issue 4 Pages e21582  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract This research study reports the assessment of complementary split ring resonators based on Gielis transformation as basic elements for the design of high‐performance microwave components in printed technology. From the electromagnetic simulation of said structures, suitable equivalent circuit models are extracted and analyzed. Physical prototypes are fabricated and tested for design validation. The obtained results confirm that the adoption of supershaped geometries enables the synthesis of very compact scalable microwave filters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000460308500020 Publication Date 2018-11-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1096-4290 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:155021 Serial 7867  
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