Shape Analysis of Complex 3D Geometry Created Using Photogrammetric 3D Digitization on the Example of Iconostases

Predmet istraživanja u okviru doktorske disertacije može se podeliti na nekoliko osnovnih tema. Kako se kao osnovni problem istraživanja postavlja analiza oblika kompleksne geometrije kreirane fotogrametrijskom 3D digitalizacijom, fokus istraživanja predstavlja primenu metode analize oblika, zasnovane na numeričkoj deskripciji, u cilju određivanja jasnih relacija između karakteristika oblika i stilskog pravca. Istraživanje u okviru doktorske disertacije bazira se na materijalnom kulturnom nasleđu, koje obuhvata ikonostase, kao jedinstvene elemente kulturnog nasleđa sa izrazito kompleksnom geometrijom. Osnovni cilj istraživanja predstavlja numeričku analizu i stilsku klasifikaciju karakteristika oblika kompleksne geometrije ikonostasa, kreirane fotogrametrijskom 3D digitalizacijom. U svrhu realizacije datog cilja, primenjen je multidisciplinarni pristup koji obuhvata širi kontekst tehnologija i znanja iz oblasti računarske grafike i matematike, koje se koriste za 3D digitalizaciju i analizu oblika. U cilju određivanja jasnih relacija između karakteristika oblika i stilskog pravca ikonostasa, predložen je metod za klasifikaciju oblika glavnih elemenata ikonostasa u odnosu na karakteristike stilskog pravca, zasnovan na metodi 2D analize oblika. Tehnike analize oblika, zasnovane na metodi deskripcije korišćene su za numeričko opisivanje i klasifikaciju stilskih karakteristika razmatranih karakteristika oblika glavnih strukturnih elemenata digitalizovanih modela ikonostasa. Primenjeni su 2D globalni deskriptori i njima pridružene mere oblika, koje su zasnovane na dimenzijama i proporcijama pojedinih elemenata ikonostasa, a koje su dizajnirane tako da odražavaju karakteristične atribute stvarnih oblika. U svrhu 3D digitalizacije, korišćena je fotogrametrijska digitalizacija, kao pouzdan i pristupačan način 3D rekonstrukcije realnih prostornih struktura. Istraživanje u okviru doktorske disertacije obuhvata i analizu i primenu metoda segmentacije oblaka tačaka i detektovanja kontura, u cilju kreiranja preciznih 2D modela kompleksne geometrije ikonostasa, koji se dalje mogu koristiti za 2D analizu oblika. Metod za 2D analizu oblika kompleksne 3D geometrije kreirane fotogrametrijskom 3D digitalizacijom, predložen u okviru doktorske disertacije, ilustrovan je na reprezentativnim primerima tri ikonostasa, nastala na području nekadašnje Karlovačke mitropolije u periodu umetničkih pravaca Baroka i Klasicizma. Rezultati istraživanja ukazali su na to da predložene metode i tehnnologije mogu biti korisne za 2D analizu oblika kompleksne geometrije digitalizovanih objekata kulturnog nasleđa. Naučni doprinos doktorske disertacije ogleda se u numeričkom pristupu analizi oblikovnih karakteristika kulturnog nasleđa, za koje se, zbog prirode kompleksne geometrije ne mogu jasno odrediti pravila oblikovanja, niti pripadnost određenom stilskom pravcu. Rezultati istraživanja takođe doprinose proširenju teorijskih znanja, dopunjujući ih saznanjima o numeričkim karakteristikama oblika analiziranih stilskih pravaca.The subject of the research is divided into several main topics. The basic problem defined within the dissertation was the shape analysis of complex geometry created by photogrammetric 3D digitization. According to that, the main focus of the research was the application of shape analysis, based on the numerical description, to determine clear relations between shape characteristics and stylistic movement. The research includes iconostases, as unique elements of material cultural heritage, characterized by complex geometry. The aim of the research was the numerical shape analysis and classification of the stylistic characteristics of the complex geometry of the iconostasis, created by photogrammetric 3D digitization. To achieve this goal, a multidisciplinary approach was applied, which includes a broader context of technologies and knowledge in the field of computer graphics and mathematics, which were used for 3D digitization and shape analysis. To determine relations between the shape characteristics and the stylistic movement of the iconostases, a method based on 2D shape analysis has beenproposed for the classification of the main iconostasis elements concerning the stylistic period to which it belongs. Shape analysis method, based on the description techniques, was used for numerical description and classification of stylistic characteristics of the considered shape characteristics of the main structural elements of the digitized iconostasis. The concept was based on the application of 2D global shape descriptors and associated shape measures. The shape measures were based on the dimensions and proportions of individual elements of the iconostasis and were designed to reflect the characteristic attributes of real shapes. For 3D digitization of iconostases, photogrammetric digitization was used, as a reliable and accessible way of 3D reconstruction of real spatial structures. In addition, the research included consideration and application of an approach to obtain 2D CAD-like visualizations of complex geometry from photogrammetric models so that the detected contours of particular object elements can be used for 2D shape analysis. The proposed method for 2D shape analysis based on photogrammetric 3D models was illustrated on representative examples of three iconostases, originated from the Baroque and Classicism art movements on the territory of the former Metropolitanate of Karlovci, in the Vojvodina region. The results indicated that the proposed methods and techniques, with certain improvements, could be useful for 2D shape analysis of complex geometry of digitized objects of cultural heritage. The dissertation contribution is reflected in the numerical approach to the shape analysis of cultural heritage characteristics, whereas the rules of design or belonging to a particular artistic style are not always obvious, due to the complex geometry. The obtained results also contribute to the broadening theoretical knowledge, supplementing it with the metric characteristics of the shapes of the analyzed stylistic directions

Shape Analysis of Complex 3D Geometry Created Using Photogrammetric 3D Digitization on the Example of Iconostases

Predmet istraživanja u okviru doktorske disertacije može se podeliti na nekoliko osnovnih tema. Kako se kao osnovni problem istraživanja postavlja analiza oblika kompleksne geometrije kreirane fotogrametrijskom 3D digitalizacijom, fokus istraživanja predstavlja primenu metode analize oblika, zasnovane na numeričkoj deskripciji, u cilju određivanja jasnih relacija između karakteristika oblika i stilskog pravca. Istraživanje u okviru doktorske disertacije bazira se na materijalnom kulturnom nasleđu, koje obuhvata ikonostase, kao jedinstvene elemente kulturnog nasleđa sa izrazito kompleksnom geometrijom. Osnovni cilj istraživanja predstavlja numeričku analizu i stilsku klasifikaciju karakteristika oblika kompleksne geometrije ikonostasa, kreirane fotogrametrijskom 3D digitalizacijom. U svrhu realizacije datog cilja, primenjen je multidisciplinarni pristup koji obuhvata širi kontekst tehnologija i znanja iz oblasti računarske grafike i matematike, koje se koriste za 3D digitalizaciju i analizu oblika. U cilju određivanja jasnih relacija između karakteristika oblika i stilskog pravca ikonostasa, predložen je metod za klasifikaciju oblika glavnih elemenata ikonostasa u odnosu na karakteristike stilskog pravca, zasnovan na metodi 2D analize oblika. Tehnike analize oblika, zasnovane na metodi deskripcije korišćene su za numeričko opisivanje i klasifikaciju stilskih karakteristika razmatranih karakteristika oblika glavnih strukturnih elemenata digitalizovanih modela ikonostasa. Primenjeni su 2D globalni deskriptori i njima pridružene mere oblika, koje su zasnovane na dimenzijama i proporcijama pojedinih elemenata ikonostasa, a koje su dizajnirane tako da odražavaju karakteristične atribute stvarnih oblika. U svrhu 3D digitalizacije, korišćena je fotogrametrijska digitalizacija, kao pouzdan i pristupačan način 3D rekonstrukcije realnih prostornih struktura. Istraživanje u okviru doktorske disertacije obuhvata i analizu i primenu metoda segmentacije oblaka tačaka i detektovanja kontura, u cilju kreiranja preciznih 2D modela kompleksne geometrije ikonostasa, koji se dalje mogu koristiti za 2D analizu oblika. Metod za 2D analizu oblika kompleksne 3D geometrije kreirane fotogrametrijskom 3D digitalizacijom, predložen u okviru doktorske disertacije, ilustrovan je na reprezentativnim primerima tri ikonostasa, nastala na području nekadašnje Karlovačke mitropolije u periodu umetničkih pravaca Baroka i Klasicizma. Rezultati istraživanja ukazali su na to da predložene metode i tehnnologije mogu biti korisne za 2D analizu oblika kompleksne geometrije digitalizovanih objekata kulturnog nasleđa. Naučni doprinos doktorske disertacije ogleda se u numeričkom pristupu analizi oblikovnih karakteristika kulturnog nasleđa, za koje se, zbog prirode kompleksne geometrije ne mogu jasno odrediti pravila oblikovanja, niti pripadnost određenom stilskom pravcu. Rezultati istraživanja takođe doprinose proširenju teorijskih znanja, dopunjujući ih saznanjima o numeričkim karakteristikama oblika analiziranih stilskih pravaca.The subject of the research is divided into several main topics. The basic problem defined within the dissertation was the shape analysis of complex geometry created by photogrammetric 3D digitization. According to that, the main focus of the research was the application of shape analysis, based on the numerical description, to determine clear relations between shape characteristics and stylistic movement. The research includes iconostases, as unique elements of material cultural heritage, characterized by complex geometry. The aim of the research was the numerical shape analysis and classification of the stylistic characteristics of the complex geometry of the iconostasis, created by photogrammetric 3D digitization. To achieve this goal, a multidisciplinary approach was applied, which includes a broader context of technologies and knowledge in the field of computer graphics and mathematics, which were used for 3D digitization and shape analysis. To determine relations between the shape characteristics and the stylistic movement of the iconostases, a method based on 2D shape analysis has beenproposed for the classification of the main iconostasis elements concerning the stylistic period to which it belongs. Shape analysis method, based on the description techniques, was used for numerical description and classification of stylistic characteristics of the considered shape characteristics of the main structural elements of the digitized iconostasis. The concept was based on the application of 2D global shape descriptors and associated shape measures. The shape measures were based on the dimensions and proportions of individual elements of the iconostasis and were designed to reflect the characteristic attributes of real shapes. For 3D digitization of iconostases, photogrammetric digitization was used, as a reliable and accessible way of 3D reconstruction of real spatial structures. In addition, the research included consideration and application of an approach to obtain 2D CAD-like visualizations of complex geometry from photogrammetric models so that the detected contours of particular object elements can be used for 2D shape analysis. The proposed method for 2D shape analysis based on photogrammetric 3D models was illustrated on representative examples of three iconostases, originated from the Baroque and Classicism art movements on the territory of the former Metropolitanate of Karlovci, in the Vojvodina region. The results indicated that the proposed methods and techniques, with certain improvements, could be useful for 2D shape analysis of complex geometry of digitized objects of cultural heritage. The dissertation contribution is reflected in the numerical approach to the shape analysis of cultural heritage characteristics, whereas the rules of design or belonging to a particular artistic style are not always obvious, due to the complex geometry. The obtained results also contribute to the broadening theoretical knowledge, supplementing it with the metric characteristics of the shapes of the analyzed stylistic directions

ANFIS based prediction of the aluminum extraction from boehmite bauxite in the Bayer process

This paper presents the results of nonlinear statistical modeling of the bauxite leaching process, as part of Bayer technology for alumina production. Based on the data, collected during the year 2011 from the industrial production in the alumina factory Birač, Zvornik (Bosnia and Herzegovina), nonlinear statistical modeling of the industrial process was performed. The model was developed as an attempt to defi ne the dependence of the Al2O3 degree of recovery as a function of input parameters of the leaching process: content of Al2O3, SiO2 and Fe2O3 in the bauxite, as well as content of Na2Ocaustic and Al2O3 in the starting sodium aluminate solution. As the statistical modeling tool, Adaptive Network Based Fuzzy Inference System (ANFIS) was used. The model, defi ned by the ANFIS methodology, expressed a high fi tting level and accordingly can be used for the effi cient prediction of the Al2O3 degree of recovery, as a function of the process inputs under the industrial conditions

Artificial neural network prediction of aluminum extraction from bauxite in the Bayer process

This paper presents the results of statistical modeling of the bauxite leaching process, as part of Bayer technology for an alumina production. Based on the data, collected during the period between 2008 - 2009 (659 days) from the industrial production in the alumina factory Birač, Zvornik (Bosnia and Herzegovina), the statistical modeling of the above mentioned process was performed. The dependant variable, which was the main target of the modeling procedure, was the degree of Al2O3 recovery from boehmite bauxite during the leaching process. The statistical model was developed as an attempt to define the dependence of the Al2O3 degree of recovery as a function of input variables of the leaching process: composition of bauxite, composition of the sodium aluminate solution and the caustic module of the solution before and after the leaching process. As the statistical modeling tools, Multiple Linear Regression Analysis (MLRA) and Artificial Neural Networks (ANNs) were used. The fitting level, obtained by using the MLRA, was R2 = 0.463, while ANN resulted with the value of R2 = 0.723. This way, the model, defined by using the ANN methodology, can be used for the efficient prediction of the Al2O3 degree of recovery as a function of the process inputs, under the industrial conditions of the alumina factory Birač, Zvornik. The proposed model also has got a universal character and, as such, is applicable in other factories practicing the Bayer technology for alumina production

Artificial neural network prediction of the aluminum extraction from bauxite in the Bayer process

This paper presents the results of statistical modeling of the bauxite leaching process, as part of Bayer technology for an alumina production. Based on the data, collected during the period between 2008 - 2009 (659 days) from the industrial production in the alumina factory Birač, Zvornik (Bosnia and Herzegovina), the statistical modeling of the above mentioned process was performed. The dependant variable, which was the main target of the modeling procedure, was the degree of Al2O3 recovery from boehmite bauxite during the leaching process. The statistical model was developed as an attempt to define the dependence of the Al2O3 degree of recovery as a function of input variables of the leaching process: composition of bauxite, composition of the sodium aluminate solution and the caustic module of the solution before and after the leaching process. As the statistical modeling tools, Multiple Linear Regression Analysis (MLRA) and Artificial Neural Networks (ANNs) were used. The fitting level, obtained by using the MLRA, was R2 = 0.463, while ANN resulted with the value of R2 = 0.723. This way, the model, defined by using the ANN methodology, can be used for the efficient prediction of the Al2O3 degree of recovery as a function of the process inputs, under the industrial conditions of the alumina factory Birač, Zvornik. The proposed model also has got a universal character and, as such, is applicable in other factories practicing the Bayer technology for alumina production

ANFIS based prediction of the aluminum extraction from boehmite bauxite in the Bayer process

This paper presents the results of nonlinear statistical modeling of the bauxite leaching process, as part of Bayer technology for alumina production. Based on the data, collected during the year 2011 from the industrial production in the alumina factory Birač, Zvornik (Bosnia and Herzegovina), nonlinear statistical modeling of the industrial process was performed. The model was developed as an attempt to defi ne the dependence of the Al2O3 degree of recovery as a function of input parameters of the leaching process: content of Al2O3, SiO2 and Fe2O3 in the bauxite, as well as content of Na2Ocaustic and Al2O3 in the starting sodium aluminate solution. As the statistical modeling tool, Adaptive Network Based Fuzzy Inference System (ANFIS) was used. The model, defi ned by the ANFIS methodology, expressed a high fi tting level and accordingly can be used for the effi cient prediction of the Al2O3 degree of recovery, as a function of the process inputs under the industrial conditions

Two-Dimensional Shape Analysis of Complex Geometry Based on Photogrammetric Models of Iconostases

Three-dimensional digitization technologies have been proved as reliable methods for detailed and accurate spatial data collection from existing cultural heritage. In addition, the point segmentation techniques are particularly relevant for contour detection and classification of the unstructured point cloud. This paper describes an approach to obtain 2D CAD-like visualizations of complex geometry from photogrammetric models so that the detected contours of particular object elements can be used for 2D shape analysis. The work process uses the point clouds derived from photogrammetric models to create the plane visualization of the object’s geometry by segmenting points based on the verticality geometric feature. The research presented is on the case studies of iconostases as the specific art and architectural elements of the Christian Orthodox church that can be appreciated only in situ. To determine relations between the characteristics of the particular shapes and the iconostases’ style origins, the mathematical method of shape analysis was applied. This study aims to numerically describe the stylistic characteristics of the shapes of the main parts of the iconostasis concerning the artistic period to which it belongs to. The concept was based on the consideration of global shape descriptors and associated shape measurements which were used to analyze and classify the stylistic characteristics of the iconostases. The methodology was applied to the representative examples of three iconostases from the Baroque and Classicism art movements. The results illustrated that the proposed methods and techniques, with certain improvements, could be helpful for CAD visualization and shape analysis of complex geometry