Hochschule Bonn-Rhein-Sieg
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Ferndetektion von schädlichen Pilzen im Weinbau durch Laserinduzierte Fluoreszenz - Weiterentwicklung des VinoLAS® Systems
No full textDer Befall mit schädlichen Pilzen führt im Weinbau zu Ertragseinbusen sowie zu ökonomischen und ökologischen Belastungen durch den präventiven Einsatz von Fungiziden. Diese könnten durch eine Früherkennung des Befalls verringert werden. Das Projekt vinoLAS® soll die kontaktlose Früherkennung des falschen Mehltaus, einer wichtigen schädlichen Pilzart im Weinbau, ermöglichen. Dabei sollen Methoden der laserinduzierten Fluoreszenzspektroskopie verwendet werden. In dieser Arbeit wird ein Detektionsmodul zur Analyse des laserinduziertem Fluoreszenzlichts in vier spektralen Kanälen entwickelt.
Die Anforderungen an das Detektionsmodul werden festgelegt und die Entwicklung erläutert. Das System lässt sich in einen optischen und elektronischen Aufbau teilen. Das Verhalten des elektronische Aufbaus wird anhand umfangreicher Messungen bestimmt und mit den Anforderungen verglichen. Es wird mit dem optischen Aufbau zu einem Gesamtsystem kombiniert. Mit diesem werden Messungen im vinoLAS® Laboraufbau durchgeführt, welche zur Verifikation mit einer Referenzmessung verglichen werden.
Die Messungen zum elektronischen Aufbau zeigen, dass alle gestellten Anforderungen erfüllt und teilweise übertroffen werden. Das entstandene Gated-Integrator System ist mit einem, deutlich teureren, kommerziellen Gated-Integrator vergleichbar, bietet dabei aber doppelt so viele Kanäle und ein 44% geringeres Rauschen. Mit der Diskussion der Messdaten werden außerdem Ansätze vorgestellt, die eine kostengünstige weiter Verbesserung des elektronischen Systems ermöglichen.
Die Messungen mit dem Gesamtsystem zeigen eine qualitative Übereinstimmung mit der Referenzmessung, es sind jedoch noch quantitative Abweichungen vorhanden, die weiter untersucht werden müssen. Außerdem zeigt sich, dass die Qualität der Messdaten durch eine Schwankung der Laserfrequenz stark eingeschränkt wird. Eine leicht implementierbare und kostengünstige Lösung für dieses Problem wird jedoch vorgestellt.
Nach Umsetzung der beiden Verbesserungsvorschläge kann das System in den vinoLAS® Aufbau integriert werden und so eine kontaktlose Früherkennung von falschem Mehltau in Weinreben ermöglichen
Introduction of Matrix-Filler Adhesion to Modelling of Elastic Moduli of Particulate Composites
No full textCube in cube elementary volume (EV) concept serves to predict a filler-content dependent Young´s moduli of particle filled composites using moduli of a matrix EM and a filler EF. Paul and Ishai-Cohen derived formulas for composites moduli considering different load transfer boundaries in the EV assuming a complete filler-matrix adhesion. In this paper it is confirmed that their models represent the upper and lower bounds, respectively, with the respect to the experimental data. However, in vast majority of composites a filler-matrix adhesion is not complete. Therefore, an adhesion factor kadh gaining values between 0 and 1 was introduced into Paul´s model to consider the reduced adhesion as the reduction of the filler-matrix contact area for glass beads filled in polar and unpolar thermoplastic matrices as well as elastomer. The evaluation of these composite systems provides reasonable adhesion coefficients of PA66 > PBT > PP > PE-LD >> BR. It was also found that stiffening only occurs if kadh exceeds the minimum value adhesion of root square of E(M) divided by E(F). The determined kadh correspond to scanning electron microscopy observations of the composites fracture surfaces. Additionally, finite element analysis of the cubic and hexagonal arrangements of the EV show that the stress distributions are different, but they affect the calculated moduli only for the filler volume contents exceeding 20 %. The introduction of the filler-matrix adhesion provides more reliable predictions of Young´s moduli of particulate composites
Bibliometric Analysis of Digital Entrepreneurial Education and Student Intention; Reviewed and Analyzed by VOSViewer from Google Scholar
No full textThe backdated research dedicated to digital entrepreneurship education is immense, which makes it difficult to create an overview. Conversely, forward-thinking bibliometric visualization mapping and clustering can assist in visualizing and structuring difficult research literature. Hence, the goal of this mapping visualization study is to thoroughly discover and create clusters of EE to convey a taxonomic structure that can oblige as a basis for upcoming research. The analyzed data, which is drawn from Google Scholar through Publish or Perish tool, contain 1000 documents published between 2007 and 2022. This taxonomy should generate stronger bonds with digital entrepreneurial education research; on the other, it should stand in international research association to boost both interdisciplinary digital entrepreneurial education and its influence on a universal basis. This work strengthens student’s understanding of current digital entrepreneurial education research by classifying and decontaminating the most powerful knowledgeable relationship among its contributions and contributors. The bibliographic analysis includes ‘citation network’, ‘author’s research area’ and ‘paper content’ regarding the desired topic. In this paper, the above three mentioned terms are integrated which produces a bibliographic model of authors, titles of their papers, keywords and abstract by using Harzing’s Publish or Perish tool for extracting data from Google Scholar and further using VOSViewer to visualize networking map of co-authorship and term co-occurrence to administer the data for an instinctive and appropriate understanding of university students concerning ‘digital entrepreneurial intention’ research. This paper uses bibliometric analysis to analyze the keyword co-occurrence and co-authorship and VOSViewer is used for visualization
Hydrogen-Bonded Cholesteric Liquid Crystals—A Modular Approach Toward Responsive Photonic Materials
No full textA supramolecular approach for photonic materials based on hydrogen-bonded cholesteric liquid crystals is presented. The modular toolbox of low-molecular-weight hydrogen-bond donors and acceptors provides a simple route toward liquid crystalline materials with tailor-made thermal and photonic properties. Initial studies reveal broad application potential of the liquid crystalline thin films for chemo- and thermosensing. The chemosensing performance is based on the interruption of the intermolecular forces between the donor and acceptor moieties by interference with halogen-bond donors. Future studies will expand the scope of analytes and sensing in aqueous media. In addition, the implementation of the reported materials in additive manufacturing and printed photonic devices is planned
Von Personal Information Management zu Vendor Management Software
No full textPersonal-Information-Management-Systeme (PIMS) gelten als Chance, um die Datensouveränität der Verbraucher zu stärken. Datenschutzbezogene Fragen sind für Verbraucher immer dort relevant, wo sie Verträge und Nutzungsbedingungen mit Diensteanbietern eingehen. Vor diesem Hintergrund diskutiert dieser Beitrag die Potenziale von VRM-Systemen, die nicht nur das Datenmanagement, sondern das gesamte Vertragsmanagement von Verbrauchern unterstützen. Dabei gehen wir der Frage nach, ob diese besser geeignet sind, um Verbraucher zu souveränem Handeln zu befähigen
Qualität der Qualitätsprüfung: Testberichte im klassischen und modernen Videospieljournalismus
No full textDie Hochzeit des gedruckten Videospieljournalismus um die Jahrtausendwende ist vorüber. Seit über 15 Jahren sind die verkauften Auflagen der klassischen Videospielzeitschriften wie Gamestar oder PC Games rückläufig. Andere Magazine wurden zwischenzeitlich aus wirtschaftlichen Gründen eingestellt, darunter PC Action oder auch der einstige Marktführer Computer Bild Spiele. Trotzdem entwickelte sich eine journalistische Gegenbewegung, die Kieron Gillen im Jahr 2004 in seinem Manifest "The New Games Journalism" begründete. Es entstanden in Deutschland Videospielzeitschriften wie GAIN oder WASD, deren Berichterstattung Videospiele weniger als Produkt, sondern zunehmend als künstlerisches Objekt wahrnehmen und sie in einen gesellschaftlichen und kulturellen Kontext einordnen.
Ungeachtet dessen erfolgt in den Redaktionen eine technische und inhaltliche Sichtung der Videospiele, die dem Publikum als Testbericht präsentiert wird. Da es sich dabei aus historischer Perspektive um den Kerninhalt von Videospielzeitschriften handelt, soll dieser als Analysegegenstand dieser Arbeit dienen und ein Indiz für die Qualität der Magazine als Ganzes sein. Mit Blick auf die unterschiedlichen Entwicklungen im Videospieljournalismus soll folgende Frage beantwortet werden: Verfügen moderne Videospielzeitschriften über eine höhere Qualität als klassische Magazine? Dazu erfolgt eine qualitative Inhaltsanalyse der Testberichte und ein Vergleich mit etablierten Qualitätsmerkmalen aus dem allgemeinen Journalismus, ebenso wie dem Fach-, Nutzwert- und Videospieljournalismus
Data cart – designing a tool for the GDPR-compliant handling of personal data by employees
No full textRemineralizing soils? The agricultural usage of silicate rock powders in the context of One Health
No full textThe concept of soil health describes the capacity of soil to fulfill essential functions and ecosystem services. Healthy soils are inextricably linked to sustainable agriculture and are crucial for the interconnected health of plants, animals, humans, and their environment ("One Health"). However, soil health is threatened through unprecedented rates of soil degradation. A major form of soil degradation is nutrient depletion, which has been seriously underestimated for potassium (K) and several micronutrients. One way to replenish K and micronutrients are multi-nutrient silicate rock powders (SRPs). Their agronomic suitability has long been questioned due to slow weathering rates, although recent studies found significant soil health improvements and challenge past objections which insufficiently addressed the factorial complexity of the weathering process. Furthermore, environmental co-benefits might arise through their mixture with livestock slurry, which could reduce the slurry’s ammonia (NH3) emissions and improve its biophysicochemical properties. However, neither SRPs effects on soil health, nor the biophysicochemical effects of mixing SRPs with livestock slurry have hitherto been comprehensively analyzed. The overall aim of this dissertation is thus to review the agricultural usage of SRPs in the context of One Health. The first part of this thesis starts with an elaboration of the health concept in general and then explores the interlinkages between soil health and One Health. Subsequently, the potentials and oftentimes bypassed problems of operationalizing soil health will be outlined, and feasible ways for its future usage are proposed. In the second part of the thesis, it is reviewed how and under which circumstances SRPs can ameliorate soil health. This is done by presenting a new framework with the most relevant factors for the usage of SRPs through which several contradictory outcomes of prior studies can be explained. A subsequent analysis of 48 crop trials reveals the potential of SRPs as K and multi-nutrient soil amendment for tropical soils, whereas the benefits for temperate soils are inconclusive. The review revealed various co-benefits that could substantially increase SRPs overall agronomic efficiency. The last part of the thesis reports about the effects of mixing two rock powders with cattle slurry. SRPs significantly increased the slurry´s CH4 emission rates, whereas the effects on NH3, CO2, and N2O emission rates were mostly insignificant. The rock powders increased the nutrient content of the slurry and altered its microbiology. In conclusion, the concept of soil health must be operationalized in more specific, practical, and context-dependent ways. Particularly in humid tropical environments, SRPs could advance low-cost soil health ameliorations, and its usage could have additional co-benefits regarding One Health. Mixing SRPs with organic materials like livestock slurry could overcome the major obstacle of their low solubility, although the effects on NH3 and greenhouse gas emissions must be further evaluated
Automatic Coding of Facial Expressions of Pain: Are We There Yet?
No full textIntroduction. The experience of pain is regularly accompanied by facial expressions. The gold standard for analyzing these facial expressions is the Facial Action Coding System (FACS), which provides so-called action units (AUs) as parametrical indicators of facial muscular activity. Particular combinations of AUs have appeared to be pain-indicative. The manual coding of AUs is, however, too time- and labor-intensive in clinical practice. New developments in automatic facial expression analysis have promised to enable automatic detection of AUs, which might be used for pain detection. Objective. Our aim is to compare manual with automatic AU coding of facial expressions of pain. Methods. FaceReader7 was used for automatic AU detection. We compared the performance of FaceReader7 using videos of 40 participants (20 younger with a mean age of 25.7 years and 20 older with a mean age of 52.1 years) undergoing experimentally induced heat pain to manually coded AUs as gold standard labeling. Percentages of correctly and falsely classified AUs were calculated, and we computed as indicators of congruency, "sensitivity/recall," "precision," and "overall agreement (F1)." Results. The automatic coding of AUs only showed poor to moderate outcomes regarding sensitivity/recall, precision, and F1. The congruency was better for younger compared to older faces and was better for pain-indicative AUs compared to other AUs. Conclusion. At the moment, automatic analyses of genuine facial expressions of pain may qualify at best as semiautomatic systems, which require further validation by human observers before they can be used to validly assess facial expressions of pain