@article{HellBrandmeierBriechleetal., author = {Hell, Maximilian and Brandmeier, Melanie and Briechle, Sebastian and Krzystek, Peter}, title = {Classification of Tree Species and Standing Dead Trees with Lidar Point Clouds Using Two Deep Neural Networks: PointCNN and 3DmFV-Net}, series = {PFG - Journal of Photogrammetry, Remote Sensing and Geoinformation Science}, volume = {90}, journal = {PFG - Journal of Photogrammetry, Remote Sensing and Geoinformation Science}, issn = {2512-2819}, doi = {10.1007/s41064-022-00200-4}, pages = {103 -- 121}, abstract = {Knowledge about tree species distribution is important for forest management and for modeling and protecting biodiversity in forests. Methods based on images are inherently limited to the forest canopy. Airborne lidar data provide information about the trees' geometric structure, as well as trees beneath the upper canopy layer. In this paper, the potential of two deep learning architectures (PointCNN, 3DmFV-Net) for classification of four different tree classes is evaluated using a lidar dataset acquired at the Bavarian Forest National Park (BFNP) in a leaf-on situation with a maximum point density of about 80 pts/m2. Especially in the case of BFNP, dead wood plays a key role in forest biodiversity. Thus, the presented approaches are applied to the combined classification of living and dead trees. A total of 2721 single trees were delineated in advance using a normalized cut segmentation. The trees were manually labeled into four tree classes (coniferous, deciduous, standing dead tree with crown, and snag). Moreover, a multispectral orthophoto provided additional features, namely the Normalized Difference Vegetation Index. PointCNN with 3D points, laser intensity, and multispectral features resulted in a test accuracy of up to 87.0\%. This highlights the potential of deep learning on point clouds in forestry. In contrast, 3DmFV-Net achieved a test accuracy of 73.2\% for the same dataset using only the 3D coordinates of the laser points. The results show that the data fusion of lidar and multispectral data is invaluable for differentiation of the tree classes. Classification accuracy increases by up to 16.3\% points when adding features generated from the multispectral orthophoto.}, language = {en} } @article{BrunnDegenWeberetal., author = {Brunn, Ansgar and Degen, Isabella and Weber, Linda and Freibott, Maximilian}, title = {3D-Vermessung der Zoolithenh{\"o}hle in der Fr{\"a}nkischen Schweiz - Eine Tropfsteinh{\"o}hle virtuell in 3D}, series = {VDV Magazin - Zeitschrift f{\"u}r Geod{\"a}sie und Geoinformatik}, journal = {VDV Magazin - Zeitschrift f{\"u}r Geod{\"a}sie und Geoinformatik}, number = {1}, publisher = {Chmielorz GmbH}, address = {Wiesbaden}, language = {de} } @inproceedings{ChizhovaBrunn, author = {Chizhova, Maria and Brunn, Ansgar}, title = {Aufbau wissenschaftlicher Partnerschaften nach Osteuropa - ein aktueller Erfahrungsbericht}, series = {DGPF-Tagung, K{\"o}ln, 2015}, booktitle = {DGPF-Tagung, K{\"o}ln, 2015}, abstract = {Der Aufbau internationaler Partnerschaften nach Osteuropa ist aktuell ein Thema f{\"u}r viele Hochschulen im deutschsprachigen Raum. Gerade die Studieng{\"a}nge der Vermessung und Geoinformatik haben oftmals Schwierigkeiten Partner im Ausland zu finden, da das Fach in vielen L{\"a}ndern nicht in der gleichen Form gelehrt wird. Dieser Beitrag zeigt aktuelle M{\"o}glichkeiten des Aufbaus von Partnerschaften nach Russland anhand der Erfahrungen der Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg-Schweinfurt auf. Dazu werden die aktuelle fachspezifische Situation in der Hochschulausbildung wie auch die Struktur der Ausbildung in Russland vorgestellt, kurz mit der Situation an der Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg-Schweinfurt verglichen sowie die M{\"o}glichkeiten der Zusammenarbeit aufgezeigt.}, language = {de} } @article{ChizhovaBrunn, author = {Chizhova, Maria and Brunn, Ansgar}, title = {ОТ ФОТОСНИМКА К ОБЛАКУ ТОЧЕК: СОЗДАНИЕ 3D-МОДЕЛЕЙ НА ОСНОВЕ ОБЛАКА ТОЧЕК, ПОЛУЧЕННЫХ ФОТОГРАММЕТРИЧЕСКИМ СПОСОБОМ}, series = {Sammelband der Akademie Iwanowo 2015}, journal = {Sammelband der Akademie Iwanowo 2015}, language = {ru} } @article{HartKoblachMoeser, author = {Hart, Lukas and Koblach, Stefan and M{\"o}ser, Michael}, title = {Automation Strategies for the Photogrammetric Reconstruction of Pipelines}, series = {PFG - Journal of Photogrammetry, Remote Sensing and Geoinformation Science}, journal = {PFG - Journal of Photogrammetry, Remote Sensing and Geoinformation Science}, number = {91}, publisher = {Springer Nature}, doi = {10.1007/s41064-023-00244-0}, pages = {313 -- 334}, abstract = {A responsible use of energy resources is currently more important than ever. For the effective insulation of industrial plants, a three-camera measurement system was, therefore, developed. With this system, the as-built geometry of pipelines can be captured, which is the basis for the production of a precisely fitting and effective insulation. In addition, the digital twin can also be used for Building Information Modelling, e.g. for planning purposes or maintenance work. In contrast to the classical approach of processing the images by calculating a point cloud, the reconstruction is performed directly on the basis of the object edges in the image. For the optimisation of the, initially purely geometrically calculated components, an adjustment approach is used. In addition to the image information, this approach takes into account standardised parameters (such as the diameter) as well as the positional relationships between the components and thus eliminates discontinuities at the transitions. Furthermore, different automation approaches were developed to facilitate the evaluation of the images and the manual object recognition in the images for the user. For straight pipes, the selection of the object edges in one image is sufficient in most cases to calculate the 3D cylinder. Based on the normalised diameter, the missing depth can be derived approximately. Elbows can be localised on the basis of coplanar neighbouring elements. The other elbow parameters can be determined by matching the back projection with the image edges. The same applies to flanges. For merging multiple viewpoints, a transformation approach is used which works with homologous components instead of control points and minimises the orthogonal distances between the component axes in the datasets.}, language = {en} } @article{OlberdingVetter, author = {Olberding, Helge and Vetter, Mark}, title = {Dynamic 3D-Cartographic Symbols for VR Geovisualizations}, series = {KN - Journal of Cartography and Geographic Information}, volume = {73}, journal = {KN - Journal of Cartography and Geographic Information}, number = {4}, issn = {2524-4965}, doi = {10.1007/s42489-023-00153-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:863-opus-53072}, pages = {265 -- 275}, abstract = {Geovisualizations that use a virtual reality headset can have a more immersive effect on users than when only a desktop application is viewed. However, to have an overview, a VR 3D map is usually viewed from a top-down perspective. On the other hand, the first-person perspective is used when the scenario is visualized as realistically as possible, and the ultimate goal is to feel present inside the 3D city. With the help of dynamic cartographic visualization methods, such as animated symbols appearing or a dynamic change of selected or complete visualization, it is possible to convey targeted information while being inside the 3D. For this purpose, techniques and ideas from cartography and video games were utilized and combined. The combination resulted in dynamically changeable symbol objects, which can be placed automatically using tables or building information, and dynamically changeable post-processing methods. Users can interactively select a predefined set of visualization methods and show/hide dynamic cartographic symbols in the running application via an interface. The study aims to develop cartographic visualization methods that can be technically used within a game engine for VR applications to improve spatial perception.}, language = {en} } @inproceedings{LangnerBrunnVoellner, author = {Langner, Normen and Brunn, Ansgar and Voellner, David}, title = {Drone-based Optimization And Validation Of Numerical Simulations Of Urban Heat Islands}, series = {SimBuild 2024 - Eleventh National Conference of IBPSA-USA, Denver, 2024}, booktitle = {SimBuild 2024 - Eleventh National Conference of IBPSA-USA, Denver, 2024}, abstract = {In this ongoing research project, advanced drone technology is employed in conjunction with simula-tion models to assess the impacts of urban climate, with a specific focus on Urban Heat Islands (UHI). The novel methodology was tested in the historical downtown areas of two German cities. Through the creation of high-resolution 3D-models of urban structures and the analysis of material properties, the research project aims to accurately predict the cli-mate impacts of urban planning decisions.The results of the project provide planners with pre-cise insights for evaluating adaptation measures and mitigating the adverse effects of climate change in cities, ultimately improving living conditions there-in. The research undertaking also pioneers the use of high-temporal-resolution drone data for analyzing temperature patterns and considers various contribu-tions to the heat island effect for comprehensive climate-adaptive urban planning.}, language = {en} } @article{MelnykBrunn, author = {Melnyk, Oleksander and Brunn, Ansgar}, title = {Analysis of Spectral Index Interrelationships for Vegetation Condition Assessment on the Example of Wetlands in Volyn Polissya, Ukraine}, series = {earth}, volume = {6}, journal = {earth}, number = {2}, doi = {10.3390/earth6020028}, pages = {21}, abstract = {The Cheremskyi Nature Reserve, situated in the Volyn region of Ukraine, constitutes a pivotal element of the European ecological network, distinguished by its distinctive mosaic of peatlands, bogs, and floodplain forests. This study utilizes Sentinel-2 satellite imagery and the Google Earth Engine (GEE) to assess the spatiotemporal patterns of various vegetation indices (NDVI, EVI, SAVI, MSAVI, GNDVI, NDRE, NDWI) from 2017 to 2024. The study aims to select the most suitable combination of vegetation spectral indices for future research. The analysis reveals significant negative trends in NDVI, SAVI, MSAVI, GNDVI, and NDRE, indicating a decline in vegetation health, while NDWI shows a positive trend, suggesting an increased vegetation water content. Correlation analysis underscores robust interrelationships among the indices, with NDVI and SAVI identified as the most significant through random forest feature importance analysis. Principal component analysis (PCA) further elucidates the primary axes of variability, emphasizing the complex interplay between vegetation greenness and moisture content. The findings underscore the utility of multi-index analyses in enhancing predictive capabilities for ecosystem monitoring and support targeted conservation strategies for the sustainable management of the Cheremskyi Nature Reserve.}, language = {en} } @inproceedings{MelnykBrunn, author = {Melnyk, Oleksandr and Brunn, Ansgar}, title = {Seasonal and Long-Term Water Regime Trends of Cheremsky Wetland: Analysis Based on Sentinel-2 Spectral Indices and Composite Indicator Development}, series = {Remote Sensing 2025}, volume = {17}, booktitle = {Remote Sensing 2025}, number = {14}, doi = {10.3390/rs17142363}, abstract = {Wetlands are critically important ecosystems, but their dynamics, especially in complex regions such as the Ukrainian Polissya, remain poorly understood. This study focuses on the Cheremsky Nature Reserve, an internationally important wetland, to assess long-term (2017-2024) seasonal (spring-summer) trends in water surface conditions. Using Sentinel-2 data and the Google Earth Engine platform, 14 spectral water indices were calculated. Their temporal trends were analyzed using Sen's method, mutual correlations, and principal component analysis (PCA) to identify the main patterns of variability. Based on the normalized trends and weights obtained from the first two principal components, an integral composite index (CI) for spring and summer seasons was developed. The results revealed seasonal differences in the behavior of the indices and their contribution to the principal components, as well as spatial differentiation of water regime trends within the reserve. The proposed CI allows for an integrated assessment of the long-term dynamics of the wetlands, which is important for the development of conservation and management strategies.}, language = {en} } @article{Brunn, author = {Brunn, Ansgar}, title = {Zwangsfreie Richtungsmessungen}, series = {zfv - Zeitschrift f{\"u}r Geod{\"a}sie, Geoinformation und Landmanagement}, volume = {149}, journal = {zfv - Zeitschrift f{\"u}r Geod{\"a}sie, Geoinformation und Landmanagement}, number = {1}, publisher = {Wißner-Verlag}, doi = {10.12902/zfv-0455-2023}, pages = {45 -- 51}, abstract = {Moderne, digitale, automatisierte Tachymeter bieten einen flexiblen Einsatz und erfordern gleichzeitig flexible Rechenverfahren. Einschr{\"a}nkungen der tradierten Auswerteverfahren in Bezug auf die Richtungsmessungen in den Zenit und in Richtung der Nullrichtung (Nullpunkt des Teilkreises) sind dabei nicht akzeptabel. Daher wird in diesem Beitrag ein neuer, auf Richtungsvektoren basierender Umgang mit Richtungsmessungen vorgeschlagen. Der direkte Vergleich des tradierten Verfahrens mit dem neuen Ansatz zeigt das neu gewonnene Potential, letztlich aber auch die Notwendigkeit, das Geod{\"a}tische Rechnen neu zu erfinden.}, language = {de} } @incollection{RuppertWoerlerBrunn, author = {Ruppert, Markus and W{\"o}rler, Jan and Brunn, Ansgar}, title = {SketchUp: Modellieren im virtuellen Raum}, series = {Technologien im Mathematikunterricht - Eine Sammlung von Trends und Ideen}, booktitle = {Technologien im Mathematikunterricht - Eine Sammlung von Trends und Ideen}, editor = {Ruppert, Markus and W{\"o}rler, Jan}, publisher = {Springer Spektrum}, address = {Wiesbaden}, isbn = {978-3-658-03007-0}, doi = {10.1007/978-3-658-03008-7_5}, pages = {135 -- 156}, abstract = {Das gesellschaftliche Interesse an virtuellen 3D-Darstellungen ist in den letzten Jahren stark gestiegen und reicht l{\"a}ngst weit {\"u}ber den Unterhaltungssektor hinaus. Damit einher schreiten auch die technischen Entwicklungen von dreidimensionalen Ein- und Ausgabem{\"o}glichkeiten unaufhaltsam fort und die Verf{\"u}gbarkeit von Laien bedienbarer digitaler Werkzeuge zur virtuellen 3D-Modellierung hat mittlerweile den Freeware-Bereich erreicht. So bietet etwa die Firma Trimble die Software „SketchUp" zum kostenlosen Download an, mit der u. a. dreidimensionale Modelle realer Geb{\"a}ude am Rechner umgesetzt und in Google Earth eingebettet werden k{\"o}nnen. Mit dem Blick auf die Einsatzm{\"o}glichkeiten der Softwareprodukte geben die Beitr{\"a}ge geben eine grundlegende Einf{\"u}hrung in ihre Bedienung und zeigen auf, wie Geb{\"a}udemodelle f{\"u}r die Verwendung mit Google Earth erstellt werden k{\"o}nnen.}, language = {de} } @article{BrunnUhlMelnyketal., author = {Brunn, Ansgar and Uhl, Anna and Melnyk, Oleksandr and Melnyk, Yuliia and Manko, Pavlo and Fesyuk, Vasyl}, title = {Remote sensing monitoring of changes in forest cover in the Volyn region}, series = {Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology}, journal = {Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology}, number = {60}, publisher = {V. N. Karazin Kharkiv National University}, doi = {10.26565/2410-7360-2024-60-19}, pages = {272 -- 283}, abstract = {This article highlights the significance of forest cover as an important indicator of the state of the environment. It discusses the findings of the Food and Agriculture Organization of the United Nations (FAO) Forest Resources Assessment (FRA) 2020 report, which states that the world's forest area has decreased by 178 million hectares since 1990. The case study of Volyn region shows how cloud processing and vegetation classification can help quantify forest dynamics from 2000 to 2020, allowing local authorities and decision makers to monitor and analyze trends in near real time. Overall, this work provides insights into the importance of monitoring forest dynamics and the potential for remote sensing technology to facilitate this process}, language = {en} } @unpublished{OkyereLuBrunn, author = {Okyere, Franz and Lu, Meng and Brunn, Ansgar}, title = {Evaluating the Quality of Open Building Datasets for Mapping Urban Inequality: A Comparative Analysis Across 5 Cities}, doi = {10.48550/arXiv.2508.12872}, language = {en} } @book{WenzelBrunn, author = {Wenzel, Daniela and Brunn, Ansgar}, title = {ЗЕМЛЕУСТРОЙСТВО В РАМКАХ ФАКУЛЬТЕТА «МЕЖЕВАНИЕ И ГЕОИНФОРМАТИКА» ИНСТИТУТА ПРИКЛАДНЫХ НАУК ВЮРЦБУРГ-ШВАЙНФУРТ (ГЕРМАНИЯ)}, series = {Sammelband der Akademie Iwanowo}, journal = {Sammelband der Akademie Iwanowo}, number = {4}, language = {ru} } @inproceedings{ErbeBrandmeierSchmittetal., author = {Erbe, Karin and Brandmeier, Melanie and Schmitt, Michael and Donbauer, Andreas and Liebscher, Jan-Andreas and Kolbe, Thomas}, title = {Detektion von Fahrradst{\"a}ndern in Luftbildern mittels Deep Learning}, series = {42. Wissenschaftlich-Technische Jahrestagung der DGPF. 5.-6. Oktober 2022 in Dresden}, volume = {30}, booktitle = {42. Wissenschaftlich-Technische Jahrestagung der DGPF. 5.-6. Oktober 2022 in Dresden}, editor = {Kersten, Thomas P. and Tilly, Nora}, issn = {0942-2870}, doi = {10.24407/KXP:1795622415}, pages = {27 -- 39}, language = {de} } @inproceedings{VetterOlberding, author = {Vetter, Mark and Olberding, Helge}, title = {Map Symbol Development for 3D Cartography suitable in VR-Environments}, series = {Abstracts ot the International Cartographic Association}, volume = {5}, booktitle = {Abstracts ot the International Cartographic Association}, doi = {10.5194/ica-abs-5-100-2022}, language = {en} } @article{ChizhovaBrunnStilla, author = {Chizhova, Maria and Brunn, Ansgar and Stilla, Uwe}, title = {Probabilistic feasibility of the HE reconstruction process of russian-orthodox churches}, series = {The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences}, volume = {XLI-B5}, journal = {The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences}, doi = {https://doi.org/10.5194/isprs-archives-XLI-B5-221-2016}, pages = {221 -- 227}, abstract = {The cultural human heritage is important for the identity of following generations and has to be preserved in a suitable manner. In the course of time a lot of information about former cultural constructions has been lost because some objects were strongly damaged by natural erosion or on account of human work or were even destroyed. It is important to capture still available building parts of former buildings, mostly ruins. This data could be the basis for a virtual reconstruction. Laserscanning offers in principle the possibility to take up extensively surfaces of buildings in its actual status. In this paper we assume a priori given 3d-laserscanner data, 3d point cloud for the partly destroyed church. There are many well known algorithms, that describe different methods of extraction and detection of geometric primitives, which are recognized separately in 3d points clouds. In our work we put them in a common probabilistic framework, which guides the complete reconstruction process of complex buildings, in our case russian-orthodox churches. Churches are modeled with their functional volumetric components, enriched with a priori known probabilities, which are deduced from a database of russian-orthodox churches. Each set of components represents a complete church. The power of the new method is shown for a simulated dataset of 100 russian-orthodox churches.}, language = {en} } @article{FroschHerrmannGrunertetal., author = {Frosch, Stefan and Herrmann, Volker and Grunert, F. and Blume, A.}, title = {Quantification of sulfur distribution on rubber surfaces by means of μ-X-ray fluorescence analysis}, series = {Polymer Testing}, volume = {128}, journal = {Polymer Testing}, number = {108237}, doi = {10.1016/j.polymertesting.2023.108237}, abstract = {A homogeneous distribution of sulfur in a rubber compound is often desired. Spatially resolved imaging techniques are useful for evaluating the distribution of this crosslinking chemical. Typical measurement methods such as SEM (scanning electron microscopy) or TEM (transmission electron microscopy) have very high resolutions. However, the sample size or the maximum area to be investigated is limited, which makes it difficult to obtain a statistically reliable determination of sulfur homogeneity across the component or sample. In this work, an alternative measurement technique is therefore presented: the μ-XRF (μ-X-ray fluorescence analysis). With the help of this method, it is possible to scan surfaces of several cm2 and to show the distribution of different chemical elements. Its measuring principle has been known for decades but has hardly been used in the rubber industry so far. The main reason for this is that its quantification process for polymeric samples is more complex than for geologic or metallic samples, which are typically been investigated with μ-XRF to date. In this paper, this issue is addressed and a solution is presented: With the help of the fundamental parameter method, the determination of sulfur homogeneity and distribution on rubber surfaces becomes possible. This opens up a variety of further possibilities for the use of μ-XRF in the rubber industry: For example, it could be used in areas of tire production, recycling of end-of-life rubber, and beyond.}, language = {en} } @article{HerrmannHanningKreyenschmidtetal., author = {Herrmann, Volker and Hanning, S. and Kreyenschmidt, M. and Wolff, A. and Ludwig, D. and Ludwig, J.}, title = {Untersuchungen zur Diffusion des Schwefels in Rezyklat-Kautschukmischungen - Teil 2: Schwefeldiffusion in Mischungen mit Gummimehl}, series = {Gummi Fasern Kunststoffe GAK}, volume = {71}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {340 -- 349}, language = {de} } @article{HerrmannSuhlFroschetal., author = {Herrmann, Volker and Suhl, L. and Frosch, S. and Endres, H.}, title = {Entwicklung eines Dynamisch-Mechanischen Indentationsmessger{\"a}ts zur Charakterisierung von Elastomeroberfl{\"a}chen auf der Mikrometerskala (µ-DMI)}, series = {Gummi Fasern Kunststoffe GAK}, volume = {75}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {30 -- 37}, language = {de} } @article{HerrmannHanningKreyenschmidt, author = {Herrmann, Volker and Hanning, S. and Kreyenschmidt, M.}, title = {Untersuchungen zur Diffusion des Schwefels in Rezyklat-Kautschukmischungen - Teil 1: Bestimmung des Diffusionskoeffizienten}, series = {Gummi Fasern Kunststoffe GAK}, volume = {71}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {232 -- 241}, language = {de} } @article{HerrmannFroschMaslowskietal., author = {Herrmann, Volker and Frosch, S. and Maslowski, T. and Werner, D.}, title = {Einsatz von definiertem Gummimehl aus NR und SBR in unterschiedlichen Matrixwerkstoffen}, series = {Gummi Fasern Kunststoffe GAK}, volume = {74}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {200 -- 207}, language = {de} } @article{BeckMaagHerrmann, author = {Beck, M. and Maag, M. and Herrmann, Volker}, title = {Konstruktion einer Entropie-Wippe zur Darstellung der Entropieelastizit{\"a}t}, series = {Gummi Fasern Kunststoffe GAK}, volume = {72}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {382 -- 385}, language = {de} } @article{HerrmannWekerle, author = {Herrmann, Volker and Wekerle, A.}, title = {Modification of Ground Rubber with Conventional Fillers by Process Engineering}, series = {Kautschuk Gummi Kunststoffe}, volume = {72}, journal = {Kautschuk Gummi Kunststoffe}, pages = {52 -- 58}, language = {en} } @article{NeckermannHerrmann, author = {Neckermann, T. and Herrmann, Volker}, title = {Simulation der Diffusion von Schwefel in Kautschukmischungen mit Gummimehl}, series = {Gummi Fasern Kunststoffe}, volume = {73}, journal = {Gummi Fasern Kunststoffe}, pages = {242 -- 246}, language = {de} } @article{HerrmannBlank, author = {Herrmann, Volker and Blank, A.}, title = {Dehnungsverhalten von Elastomeren mit Gummimehl}, series = {Gummi Fasern Kunststoffe GAK}, volume = {70}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {726 -- 736}, language = {de} } @article{Herrmann, author = {Herrmann, Volker}, title = {Nachhaltigkeit in der Gummi- und Reifenindustrie}, series = {Kautschuk Gummi Kunststoffe}, volume = {76}, journal = {Kautschuk Gummi Kunststoffe}, pages = {8 -- 9}, language = {de} } @article{SchueleinChristosKBolketal., author = {Sch{\"u}lein, Tim and Christos K., Georgantopoulos and Bolk, Lars and Herrmann, Volker and Wilhelm, Manfred}, title = {Thermo-Mechanical Degradation Kinetics of a High-Density Poly(Ethylene) Using a Closed-Cavity Rheometer}, series = {Journal of Applied Polymer Science}, volume = {142}, journal = {Journal of Applied Polymer Science}, number = {17}, doi = {10.1002/app.56784}, abstract = {Mechanical recycling of polymers is an essential aspect to achieve circular economy. High shear stress, excessive temperature, and long residence time during reprocessing cause thermo-mechanical degradation of the polymer. Therefore, it is important to understand and quantify this degradation kinetics. Common ways to simulate degradation are very time and material consuming and clear insights into the respective influence of temperature and shear stress on degradation are rare. Within this publication a method is developed using a commercially available, close-cavity rheometer to emulate processing conditions in a defined way. This allows monitoring and predicting the behavior of a high-density polyethylene (HDPE) and quantify degradation kinetics and changes in the polymer topology. HDPE is selected as a model polymer due to its large production and wide range of applications. Different treated samples are analyzed by various rheological methods. Additionally, molecular characterization is conducted. A kinetic model to predict the changes in the molecular weight as a function of in-phase shear stress, temperature and duration during treatment is presented. The calculated activation energy for the initiation reaction agrees with the activation energy for HDPE degradation from thermogravimetric analysis. This activation energy is lowered by in-phase shear stress, modified by a factor of 1.7 m3 mol-1.}, language = {en} } @article{HerrmannFroschSchueleinetal., author = {Herrmann, Volker and Frosch, Stefan and Sch{\"u}lein, Tim and Grunert, Fabian and Blume, Anke}, title = {Sulfur Diffusion Studies Imitating Recycled Ground-Rubber-Containing Compounds}, series = {Polymers}, volume = {16}, journal = {Polymers}, number = {22}, doi = {10.3390/polym16223112}, abstract = {n-rubber properties of vulcanizates deteriorate in the presence of incorporated recycled ground rubber (GR). This behavior is partly explained by a possible diffusion of sulfur from the rubber matrix into the GR. Therefore, the sulfur concentration and, thus, the crosslink density in the matrix are reduced. This phenomenon was further investigated in this research work using two spatially resolved methods that supplement each other: the diffusion of soluble sulfur in GR-containing compounds was locally investigated via Micro X-Ray Fluorescence analysis. Viscoelastic properties were also determined spatially by the Micro Dynamic-Mechanical Indentation method. Combining the results of both methods, local concentrations of sulfur were related to local viscoelastic properties, revealing great differences in crosslink density at the interface between the GR and matrix material. In this way, it is shown that sulfur is capable of diffusing several mm, which locally doubles its concentration with respect to the sulfur content of the compound formulation. This, in turn, negatively impacts the homogeneity of crosslink density in both the matrix and GR, revealing a local increase in the elastic stiffness of 100 \%. In addition, it was found that the vulcanization characteristics of the used polymers determine the amount of sulfur diffusion and, thus, the change in viscoelastic properties.}, language = {en} } @inproceedings{Herrmann, author = {Herrmann, Volker}, title = {{\"U}berlegungen und Ergebnisse zur intrinsischen Deformation von Elastomeren mit Gummimehl}, series = {113. Tagung der Regionalgruppe S{\"u}d der Deutschen Kautschuk Gesellschaft DKG, W{\"u}rzburg}, booktitle = {113. Tagung der Regionalgruppe S{\"u}d der Deutschen Kautschuk Gesellschaft DKG, W{\"u}rzburg}, language = {de} } @article{Herrmann, author = {Herrmann, Volker}, title = {Internationalisierung als m{\"o}gliche L{\"o}sung f{\"u}r das Problem des Fachkr{\"a}ftemangels}, series = {Kautschuk Gummi Kunststoffe 77}, journal = {Kautschuk Gummi Kunststoffe 77}, pages = {8 -- 9}, language = {de} } @article{DavidovicKuzmicVasicetal., author = {Davidovic, Marina and Kuzmic, Tatjana and Vasic, Dejan and Wich, Valentin and Brunn, Ansgar and Bulatovic, Vladimir}, title = {Methodology for Road Defect Detection and Administration based on Mobile Mapping Data}, series = {Computer Modeling in Engineering \& Sciences}, volume = {129}, journal = {Computer Modeling in Engineering \& Sciences}, number = {1}, doi = {https://doi.org/10.32604/cmes.2021.016071}, pages = {207 -- 226}, abstract = {A detailed inspection of roads requires highly detailed spatial data with sufficient precision to deliver an accurate geometry and to describe road defects visually. This paper presents a novel method for the detection of road defects. The input data for road defect detection included point clouds and orthomosaics gathered by mobile mapping technology. The defects were categorized in three major groups with the following geometric primitives: points, lines and polygons. The method suggests the detection of point objects from matched point clouds, panoramic images and ortho photos. Defects were mapped as point, line or polygon geometries, directly derived from orthomosaics and panoramic images. Besides the geometric position of road defects, all objects were assigned to a variety of attributes: defect type, surface material, center-of-gravity, area, length, corresponding image of the defect and degree of damage. A spatial dataset comprising defect values with a matching data type was created to perform the attribute analysis quickly and correctly. The final product is a spatial vector data set, consisting of points, lines and polygons, which contains attributes with further information and geometry. This paper demonstrates that mobile mapping suits a large-scale feature extraction of road infrastructure defects. By its simplicity and flexibility, the presented methodology allows it to be easily adapted to extract further feature types with their attributes. This makes the proposed approach a vital tool for data extraction settings with multiple mobile mapping data analysts, e.g., offline crowdsourcing.}, language = {en} } @article{SelenskiReussRothetal., author = {Selenski, J{\"u}rgen and Reuß, Oliver and Roth, Jonas and H{\"a}ndler, Verena and Badecki, Tomasz and Schirmer, Uwe and Bogner, Markus and Wagner, Andreas and Brunn, Ansgar}, title = {Integration von 3D-Laserscanning in die Rohstoffgewinnung im Untertagebau}, series = {DGPF-Jahrestagung 2023}, journal = {DGPF-Jahrestagung 2023}, editor = {Kersten, Thomas P. and Tilly, Nora}, address = {M{\"u}nchen}, pages = {251 -- 262}, language = {de} } @incollection{HerrmannMoegingerUnseld, author = {Herrmann, Volker and M{\"o}ginger, Bernhard and Unseld, Claus}, title = {Quasi Static Indentation Measurements: A Tool for Micromechanical Investigations of Interfaces in Polymer Materials}, series = {Forschungsspitzen und Spitzenforschung}, booktitle = {Forschungsspitzen und Spitzenforschung}, editor = {Zacharias, Christoph}, publisher = {Physica}, address = {Heidelberg}, isbn = {978-3-7908-2126-0}, doi = {https://doi.org/10.1007/978-3-7908-2127-7_28}, pages = {315 -- 327}, abstract = {The ongoing miniaturization, multi-layer structure parts and hybrid parts require methods to determine mechanical properties on a micro-scale. However, there is a gap in measuring techniques. On one hand there are the classical methods to measure hardness e.g. VICKERS, ROCKWELL, UNIVERSAL, IRHD etc having resolutions typically above 100μm. On the other hand there are well-developed AFM methods that allow for the determination of mechanical properties in the nanometer range. This paper describes an indentation technique that yields data of mechanical properties in the micrometer range between typically 5 to 50 μm. The measuring device and the data evaluation is presented. Results of micro-mechanical mapping are shown for NR-SBR rubber interfaces, a fuel tank and a part manufactured by two component injection moulding. Finally, the measured micro-mechanical stiffness is compared to the YOUNG's modulus of the corresponding materials.}, language = {en} } @article{HerrmannMoldovanFecheteetal., author = {Herrmann, Volker and Moldovan, Dumitrita and Fechete, Radu and Demco, Dan Eugen and Culea, Eugen and Bl{\"u}mich, Bernhard and Heinz, Manfred}, title = {Heterogeneity of Nanofilled EPDM Elastomers Investigated by Inverse Laplace Transform 1H NMR Relaxometry and Rheometry}, series = {Macromolecular Chemistry and Physics}, volume = {211}, journal = {Macromolecular Chemistry and Physics}, number = {14}, doi = {https://doi.org/10.1002/macp.201000086}, pages = {1579 -- 1594}, abstract = {The heterogeneous effects due to filler interactions and chain dynamics of reinforcing nano-filler particles were characterized on a series of filled EPDM elastomers using the Payne effect and low field NMR, 1H transverse (T2), longitudinal (T1) and longitudinal in rotating frame (T1ρ) relaxation time measurements. Measurement of the Payne effect and NMR relaxation curves were used to obtain the distribution of filler/filler interactions and chain dynamics by one-dimensional Laplace inversion. Distributions of shear-strain constants in the Payne effect reveal the existence of weak, medium and strong filler/filler interactions which were correlated to filler properties and content. The analysis of relaxation-time distributions leads to the identification of multimodal polymer network dynamics.}, language = {en} } @article{HerrmannMoldovanFecheteetal., author = {Herrmann, Volker and Moldovan, Dumitrita and Fechete, Radu and Demco, Dan Eugen and Culea, Eugen and Bl{\"u}mich, Bernhard and Heinz, Manfred}, title = {The heterogeneity of segmental dynamics of filled EPDM by 1H transverse relaxation NMR}, series = {J. Magn. Res.}, volume = {208}, journal = {J. Magn. Res.}, number = {1}, doi = {https://doi.org/10.1016/j.jmr.2010.10.019}, pages = {156 -- 162}, language = {en} } @article{HerrmannNiedermeier, author = {Herrmann, Volker and Niedermeier, W.}, title = {Interpretation of Filler Networking of Loaded Rubbers via Mastercurves}, series = {Kautschuk Gummi Kunststoffe}, volume = {63}, journal = {Kautschuk Gummi Kunststoffe}, pages = {559 -- 564}, language = {en} } @article{Herrmann, author = {Herrmann, Volker}, title = {Moderne Elastomere}, series = {Ingenieurspiegel}, journal = {Ingenieurspiegel}, number = {3}, pages = {100 -- 101}, language = {de} } @article{HerrmannHeinrich, author = {Herrmann, Volker and Heinrich, A.}, title = {Influence of the modification of ground truck tyres as an additive on the properties of a truck tread compound}, series = {International Polymer Science and Technology}, volume = {44}, journal = {International Polymer Science and Technology}, number = {5}, doi = {10.1177/0307174X1704400501}, pages = {T/1 -- T/9}, abstract = {Commercially available ground tyre rubber (GTR) made exclusively from post-consumer truck tyres was mixed into a typical truck tyre tread compound. As already shown in a previous study, this leads to a distinct deterioration in properties. The goal of the present investigation was to minimise these property losses through modification of the GTR in terms of processing methods. Modification methods already documented in the literature were used, e.g. application of sulphur and crosslinking agents to the GTR and the use of trans-polyoctenamer as well as liquid polymers, which in principle provide the potential for crosslinking of the GTR and polymer matrix through the availability of double bonds. For some methods of modification, small improvements are observed in comparison with the unmodified GTR. However, none of the GTR modifications reaches the level of the reference compound without GTR. An economic estimate for the modification with the highest potential for technical success shows that, in practice, considerable costs must be expected.}, language = {en} } @article{HerrmannSchulz, author = {Herrmann, Volker and Schulz, A.}, title = {Der Einfluss von Lkw-Reifenmehl als Additiv auf die Eigenschaften einer Lkw-Lauffl{\"a}chenmischung}, series = {Gummi Fasern Kunststoffe GAK}, volume = {69}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {698 -- 705}, abstract = {Commercially available ground tire rubber (GRT) was mixed into a typical truck tire tread compound. The GRT originated from postconsumer truck tires and differed in the manufacturing process (cryogenic and warm grinding, resp.) as well as the ageing state. Regardless of the grinding process type, the vulcanizates containing GRT became softer, mechanical properties and the abrasion resistance worse and the Payne effect decreased. Additional artificial ageing of the GRT showed no further effects regarding property changes when adding GRT. Based on the vulcameter curves it could be seen, that the curing behaviour of the compounds changed and the crosslink density of the matrix obviously decreased by adding GRT. Additional !'jXRF images and measurements for dynamic local indentation indicated increased sulphur content inside the GRT particles.}, language = {de} } @article{HerrmannNassLemmichetal., author = {Herrmann, Volker and Naß, Felix and Lemmich, Sebastian and Wachter, Florian}, title = {Einfluss des EFE-Spritzsystems auf Heizzeitreduzierung und Eigenschaften der gespritzten Bauteile - Teil 1: „Betrachtung der Heizzeitreduzierung {\"u}ber reaktionskinetische Berechnung und begleitende Untersuchungen zu Bauteil- und Vernetzungsdichte mittels NMR-Bildgebung"}, series = {Gummi Fasern Kunststoffe GAK}, volume = {66}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {37 -- 42}, language = {de} } @article{HerrmannNassLemmichetal., author = {Herrmann, Volker and Naß, Felix and Lemmich, Sebastian and Wachter, Florian}, title = {Einfluss des EFE-Spritzsystems auf Heizzeitreduzierung und Eigenschaften der gespritzten Bauteile - Teil 3: „Absch{\"a}tzung der Scherenergie und Einfluss der Drossel auf ausgew{\"a}hlte Eigenschaften der gespritzten Bauteile"}, series = {Gummi Fasern Kunststoffe GAK}, volume = {66}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {180 -- 184}, language = {de} } @article{HerrmannNassLemmichetal., author = {Herrmann, Volker and Naß, Felix and Lemmich, Sebastian and Wachter, Florian}, title = {Einfluss des EFE-Spritzsystems auf Heizzeitreduzierung und Eigenschaften der gespritzten Bauteile - Teil 2: „Einfluss der Verfahrensparameter des Spritzgießprozesses auf die Heizzeitreduzierung"}, series = {Gummi Fasern Kunststoffe GAK}, volume = {66}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {108 -- 112}, language = {de} } @article{HerrmannHeinrich, author = {Herrmann, Volker and Heinrich, A.}, title = {Einfluss der Modifikation von LKW-Reifenmehl als Additiv auf die Eigenschaften einer LKW-Lauffl{\"a}chenmischung}, series = {Gummi Fasern Kunststoffe GAK}, volume = {70}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {88 -- 95}, language = {de} } @article{HerrmannSpeyerLeiber, author = {Herrmann, Volker and Speyer, Y. and Leiber, J.}, title = {Herstellung und Verarbeitung von sortenreinem Gummimehl im Labormaßstab}, series = {Gummi Fasern Kunststoffe GAK}, volume = {70}, journal = {Gummi Fasern Kunststoffe GAK}, pages = {240 -- 247}, language = {de} } @article{HerrmannSchulz, author = {Herrmann, Volker and Schulz, A.}, title = {Influence of ground truck tires as an additive on the properties of a truck tread compound}, series = {Rubber Fibres Plastics RFP}, volume = {13}, journal = {Rubber Fibres Plastics RFP}, pages = {24 -- 30}, language = {en} } @inproceedings{HaendlerReussRothetal., author = {H{\"a}ndler, Verena and Reuß, Oliver and Roth, Jonas and Selenski, J{\"u}rgen and Brunn, Ansgar}, title = {Punktwolkenbasierte 3D-Vermessung f{\"u}r KMU in Handwerk und Bauwesen}, series = {Publikationen der Deutschen Gesellschaft f{\"u}r Photogrammetrie, Fernerkundung und Geoinformation e.V.}, volume = {30}, booktitle = {Publikationen der Deutschen Gesellschaft f{\"u}r Photogrammetrie, Fernerkundung und Geoinformation e.V.}, abstract = {Hochschulen f{\"u}r angewandte Wissenschaften entwickeln best{\"a}ndig die Lehre nicht nur f{\"u}r die eigenen Studierenden, sondern auch die Methoden f{\"u}r den Wissenstransfer in die Unternehmen weiter. Neue didaktische Konzepte werden f{\"u}r anstehende Fachthemen ausprobiert. Im Rahmen des Projekts „Fr{\"u}he Digitalisierung technischer Planungsprozesse im Bauwesen und Handwerk f{\"u}r kleine und mittlere Unternehmen" (DiTeP4KMU) sollen daher aktuelle Methoden der Wissensvermittlung (Online Lehrangebote, Blended Learning sowie hybride Lehrveranstaltungsformen) in die berufsbegleitende Weiterbildung {\"u}bertragen und realisiert werden. Das Projekt ist eine Fortsetzung und Erweiterung der bereits an der Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg-Schweinfurt umgesetzten Projekte „Digitale Photogrammetrie und Bildverarbeitung f{\"u}r kleine und mittlere Unternehmen (DiPhoBi4KMU)" und „Mobile 3D Vermessung f{\"u}r kleine und mittlere Unternehmen" (MV-3D4KMU). Ziel des aktuellen Projekts ist die Prozessoptimierung in KMU durch mobile 3D-Vermessung anhand hybrider Wissensvermittlung in Form von E-Learning Angeboten sowie Pr{\"a}senzveranstaltungen in Form von Netzwerktreffen und Aktionen. Der fachliche Fokus liegt dabei auf der st{\"a}rkeren Verbreitung der 3D-Daten f{\"u}r allt{\"a}gliche Aufgaben - insbesondere der schnell zu generierenden 3D-Punktwolken durch moderne Messsysteme - in die Arbeitsprozesse im Bauwesen und Handwerk, in Zusammenarbeit mit den beteiligten Unternehmen. Die Erfahrungen in dem Projekt zeigen bereits nach ca. sechs Monaten ein großes Interesse und best{\"a}tigen die Konzeption des Projektentwurfs.}, language = {de} } @inproceedings{MeyerBrunn, author = {Meyer, Theresa and Brunn, Ansgar}, title = {3D Point Clouds in PostgreSQL/PostGIS for Applications in GIS and Geodesy}, series = {Proceedings of the 5th International Conference on Geographical Information Systems Theory, Applications and Management}, booktitle = {Proceedings of the 5th International Conference on Geographical Information Systems Theory, Applications and Management}, publisher = {SCITEPRESS - Science and Technology Publications}, isbn = {978-989-758-371-1}, doi = {10.5220/0007840901540163}, pages = {154 -- 163}, abstract = {Besides the common approach of an exclusively file based management of 3D point clouds, meanwhile it is possible to store and process this special type of massive geodata within spatial database systems. Users benefit from the general advantages of database solutions and especially from the potentials of a combined analysis of original 3D point clouds, 2D rasters, 3D voxel stacks and 2D and 3D vector data in order to gain valuable geo- information. This paper describes the integration of 3D point clouds into an open source PostgreSQL/PostGIS database using the Pointcloud extension and functions of the Point Data Abstraction Library (PDAL). The focus is on performing three-dimensional spatial queries and the evaluation of different tiling methods for the organization of 3D point clouds into table rows, regarding memory space, performance of spatial queries and effects on interactions between point clouds and other GIS features within the database. A new approach for an optimized point cloud tiling, considering the individual geometric characteristic of a 3D point cloud, is presented. The results show that an individually selected storage structure for a point cloud is crucial for low memory consumption and high-performance 3D queries in PostGIS applications, taking account of its three-dimensional spatial extent and point density.}, language = {en} } @article{ChizhovaGurianovHessetal., author = {Chizhova, Maria and Gurianov, Andrey and Hess, Mona and Luhmann, Thomas and Brunn, Ansgar and Stilla, Uwe}, title = {Semantic segmentation of building elements using point cloud hashing}, series = {ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences}, volume = {VLII-2}, journal = {ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences}, doi = {https://doi.org/10.5194/isprs-archives-XLII-2-241-2018}, pages = {241 -- 250}, abstract = {For the interpretation of point clouds, the semantic definition of extracted segments from point clouds or images is a common problem. Usually, the semantic of geometrical pre-segmented point cloud elements are determined using probabilistic networks and scene databases. The proposed semantic segmentation method is based on the psychological human interpretation of geometric objects, especially on fundamental rules of primary comprehension. Starting from these rules the buildings could be quite well and simply classified by a human operator (e.g. architect) into different building types and structural elements (dome, nave, transept etc.), including particular building parts which are visually detected. The key part of the procedure is a novel method based on hashing where point cloud projections are transformed into binary pixel representations. A segmentation approach released on the example of classical Orthodox churches is suitable for other buildings and objects characterized through a particular typology in its construction (e.g. industrial objects in standardized enviroments with strict component design allowing clear semantic modelling).}, language = {en} } @article{ChizhovaKorovinGurianovetal., author = {Chizhova, Maria and Korovin, Dmitriyi and Gurianov, Andrey and Brodovskii, Maxim and Brunn, Ansgar and Stilla, Uwe and Luhmann, Thomas}, title = {Probabilistic Reconstruction of orthodox Churches from precision Point Clouds using Bayesian Networks and Cellular Automata}, series = {The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences}, volume = {VLII-2/W3}, journal = {The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences}, doi = {doi:10.5194/isprs-archives-XLII-2-W3-187-2017}, pages = {187 -- 194}, abstract = {The point cloud interpretation and reconstruction of 3d-buildings from point clouds has already been treated for a few decades. There are many articles which consider the different methods and workows of the automatic detection and reconstruction of geometrical objects from point clouds. Each method is suitable for the special geometry type of object or sensor. General approaches are rare. In our work we present an algorithm which develops the optimal process sequence of the automatic search, detection and reconstruction of buildings and building components from a point cloud. It can be used for the detection of the set of geometric objects to be reconstructed, independent of its destruction. In a simulated example we reconstruct a complete Russian-orthodox church starting from the set of detected structural components and reconstruct missing components with high probability.}, language = {en} }