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On the basis of bivariate data, assumed to be observations of independent copies of a random vector (S,N), we consider testing the hypothesis that the distribution of (S,N) belongs to the parametric class of distributions that arise with the compound Poisson exponential model. Typically, this model is used in stochastic hydrology, with N as the number of raindays, and S as total rainfall amount during a certain time period, or in actuarial science, with N as the number of losses, and S as total loss expenditure during a certain time period. The compound Poisson exponential model is characterized in the way that a specific transform associated with the distribution of (S,N) satisfies a certain differential equation. Mimicking the function part of this equation by substituting the empirical counterparts of the transform we obtain an expression the weighted integral of the square of which is used as test statistic. We deal with two variants of the latter, one of which being invariant under scale transformations of the S-part by fixed positive constants. Critical values are obtained by using a parametric bootstrap procedure. The asymptotic behavior of the tests is discussed. A simulation study demonstrates the performance of the tests in the finite sample case. The procedure is applied to rainfall data and to an actuarial dataset. A multivariate extension is also discussed.
Advances in polymer science have significantly increased polymer applications in life sciences. We report the use of free-standing, ultra-thin polydimethylsiloxane (PDMS) membranes, called CellDrum, as cell culture substrates for an in vitro wound model. Dermal fibroblast monolayers from 28- and 88-year-old donors were cultured on CellDrums. By using stainless steel balls, circular cell-free areas were created in the cell layer (wounding). Sinusoidal strain of 1 Hz, 5% strain, was applied to membranes for 30 min in 4 sessions. The gap circumference and closure rate of un-stretched samples (controls) and stretched samples were monitored over 4 days to investigate the effects of donor age and mechanical strain on wound closure. A significant decrease in gap circumference and an increase in gap closure rate were observed in trained samples from younger donors and control samples from older donors. In contrast, a significant decrease in gap closure rate and an increase in wound circumference were observed in the trained samples from older donors. Through these results, we propose the model of a cell monolayer on stretchable CellDrums as a practical tool for wound healing research. The combination of biomechanical cell loading in conjunction with analyses such as gene/protein expression seems promising beyond the scope published here.
This study reviews the practice of brake tests in freight railways, which is time consuming and not suitable to detect certain failure types. Public incident reports are analysed to derive a reasonable brake test hardware and communication architecture, which aims to provide automatic brake tests at lower cost than current solutions. The proposed solutions relies exclusively on brake pipe and brake cylinder pressure sensors, a brake release position switch as well as radio communication via standard protocols. The approach is embedded in the Wagon 4.0 concept, which is a holistic approach to a smart freight wagon. The reduction of manual processes yields a strong incentive due to high savings in manual
labour and increased productivity.
Inhaltsverzeichnis - Bachelorarbeiten
1. The impact of the EU non-financial reporting directive on sustainability reporting practices of DAX 30 companies
- Lene Christin Blöcker 4 - 29
2. Kurzarbeit als Krisenbewältigungsinstrument – Die arbeitsrechtlichen Voraussetzungen für die wirksame Einführung von Kurzarbeit
- Julia Esser 30 - 87
3. Die virtuelle Hauptversammlung der Aktiengesellschaft – Notlösung während der Corona-Pandemie oder dauerhafte Alternative?
- Pauline Hengstebeck 88 - 152
4. Die psychische Gesundheit am Arbeitsplatz – Aktuelle Problematik, Ursachenforschung, Folgen, rechtliche Rahmenbedingungen und geeignete Präventionsmaßnahmen aus Arbeitgebersicht
- Carolin Venrath 153 - 224
Inhaltsverzeichnis – Masterarbeiten
The influence of religion on the representation of women in politics
- Eva Scholtes 225 - 345
Inhaltsverzeichnis - Bachelorarbeiten
1. Testamentsgestaltung bei Patchworkfamilien – Lösungsansätze für typische
Praxisprobleme unter Berücksichtigung der Interessenlagen der Parteien
- Ronja Bundrock 4 - 58
2. Die Haftung des AG-Vorstands gegenüber der Gesellschaft in unterneh-
mensinternen und -externen Krisen
- Nico Kremers 59 - 122
3. The Relationship of the Ex-Ante Uncertainty about the Value of a Stock
and its IPO Underpricing – An Analysis of the German Market
- Lennard Pankok 123 - 179
4. Attractiveness Bias in Venture Capital – An Analysis of Investor Decision
Making in “Die Höhle der Löwen”
- Theresa Maria Weisheit 180 - 242
Inhaltsverzeichnis – Masterarbeiten
Erhöhung der Energieautarkie in der Backbranche – Anwendung von bidi-
rektionalem Laden und dessen Auswirkungen auf die Geschäftsprozesse
und Informationssysteme
- Jasper Spoede 243 - 355
The fourth industrial revolution presents a multitude of challenges for industries, one of which being the increased flexibility required of manufacturing lines as a result of increased consumer demand for individualised products. One solution to tackle this challenge is the digital twin, more specifically the standardised model of a digital twin also known as the asset administration shell. The standardisation of an industry wide communications tool is a critical step in enabling inter-company operations. This paper discusses the current state of asset administration shells, the frameworks used to host them and their problems that need to be addressed. To tackle these issues, we propose an event-based server capable of drastically reducing response times between assets and asset administration shells and a multi-agent system used for the orchestration and deployment of the shells in the field.
aco : eine digitale Anwendung zur Verbesserung der Lebensqualität
von Neurodermitis-Patient:innen
(2022)
Neurodermitis hat in den letzten Jahrzehnten deutlich zugenommen. Etwa 10 bis 15 Prozent der Kinder und 2,5 bis 3,5 Prozent der Erwachsenen sind davon betroffen. Für sie stellen Auswirkungen der Hautkrankheit auf Körper und Psyche eine enorme Einschränkung der Lebensqualität dar.
Die App „aco“ möchte Neurodermitis-Patient:Innen dabei unterstützen, ihre Behandlung selbst in die Hand zu nehmen. Eine ganzheitliche Therapie umfasst eben nicht nur Fachpersonen, sondern auch Patient:Innen selbst. Durch eine regelmäßige Dokumentation ermöglicht die Anwendung eine aktive Auseinandersetzung mit der Krankheit. Triggerfaktoren werden ausgewertet und es wird Wissen über Behandlungsmöglichkeiten vermittelt. Zudem wird ein Austausch ermöglicht, der emotionale und praktische Unterstützung bieten soll. Damit möchte „aco“ Betroffenen eine Möglichkeit geben, das Ruder selbst in die Hand zu nehmen und leistet damit einen wichtigen Beitrag zur Therapie von Neurodermitis.
Wo einst fast lückenlos Laubwälder wuchsen, steht heute nur noch ein Drittel der ursprünglichen Waldfläche. Echte Urwälder gibt es hier schon lange nicht mehr: Die Rede ist vom deutschen Wald.
Unsere Welt ist im Wandel. Auch in unseren heimischen Wäldern lassen sich die Einflüsse von Mensch und Klimawandel auf die Biodiversität beobachten.
Die illustrierte Publikation „Adapt or die“ lädt mit mehr als 80 großformatigen Artenportraits, Habitat-Kartierungen und gestalteten Themenklappenseiten zur Auseinandersetzung mit dem Wandel unserer heimischen Wälder ein. Dabei sensibilisiert sie für einen bewussteren Umgang mit Umwelt und Natur. Erweiterungen durch Augmented Reality bieten vereinzelt neben dem Printprodukt aktualisierbare Prognosen, digital und ressourcenschonend.
Das komplexe Ökosystem des Waldes reagiert empfindlich auf Veränderungen: Wer sich nicht anpassen kann, wird verschwinden.
Sleep spindles are neurophysiological phenomena that appear to be linked to memory formation and other functions of the central nervous system, and that can be observed in electroencephalographic recordings (EEG) during sleep. Manually identified spindle annotations in EEG recordings suffer from substantial intra- and inter-rater variability, even if raters have been highly trained, which reduces the reliability of spindle measures as a research and diagnostic tool. The Massive Online Data Annotation (MODA) project has recently addressed this problem by forming a consensus from multiple such rating experts, thus providing a corpus of spindle annotations of enhanced quality. Based on this dataset, we present a U-Net-type deep neural network model to automatically detect sleep spindles. Our model’s performance exceeds that of the state-of-the-art detector and of most experts in the MODA dataset. We observed improved detection accuracy in subjects of all ages, including older individuals whose spindles are particularly challenging to detect reliably. Our results underline the potential of automated methods to do repetitive cumbersome tasks with super-human performance.
In order to realistically predict and optimize the actual performance of a concentrating solar power (CSP) plant sophisticated simulation models and methods are required. This paper presents a detailed dynamic simulation model for a Molten Salt Solar Tower (MST) system, which is capable of simulating transient operation including detailed startup and shutdown procedures including drainage and refill. For appropriate representation of the transient behavior of the receiver as well as replication of local bulk and surface temperatures a discretized receiver model based on a novel homogeneous two-phase (2P) flow modelling approach is implemented in Modelica Dymola®. This allows for reasonable representation of the very different hydraulic and thermal properties of molten salt versus air as well as the transition between both. This dynamic 2P receiver model is embedded in a comprehensive one-dimensional model of a commercial scale MST system and coupled with a transient receiver flux density distribution from raytracing based heliostat field simulation. This enables for detailed process prediction with reasonable computational effort, while providing data such as local salt film and wall temperatures, realistic control behavior as well as net performance of the overall system. Besides a model description, this paper presents some results of a validation as well as the simulation of a complete startup procedure. Finally, a study on numerical simulation performance and grid dependencies is presented and discussed.
Bacterial cellulose (BC) is a biopolymer produced by different microorganisms, but in biotechnological practice, Komagataeibacter xylinus is used. The micro- and nanofibrillar structure of BC, which forms many different-sized pores, creates prerequisites for the introduction of other polymers into it, including those synthesized by other microorganisms. The study aims to develop a cocultivation system of BC and prebiotic producers to obtain BC-based composite material with prebiotic activity. In this study, pullulan (PUL) was found to stimulate the growth of the probiotic strain Lactobacillus rhamnosus GG better than the other microbial polysaccharides gellan and xanthan. BC/PUL biocomposite with prebiotic properties was obtained by cocultivation of Komagataeibacter xylinus and Aureobasidium pullulans, BC and PUL producers respectively, on molasses medium. The inclusion of PUL in BC is proved gravimetrically by scanning electron microscopy and by Fourier transformed infrared spectroscopy. Cocultivation demonstrated a composite effect on the aggregation and binding of BC fibers, which led to a significant improvement in mechanical properties. The developed approach for “grafting” of prebiotic activity on BC allows preparation of environmentally friendly composites of better quality.
Wearable EEG has gained popularity in recent years driven by promising uses outside of clinics and research. The ubiquitous application of continuous EEG requires unobtrusive form-factors that are easily acceptable by the end-users. In this progression, wearable EEG systems have been moving from full scalp to forehead and recently to the ear. The aim of this study is to demonstrate that emerging ear-EEG provides similar impedance and signal properties as established forehead EEG. EEG data using eyes-open and closed alpha paradigm were acquired from ten healthy subjects using generic earpieces fitted with three custom-made electrodes and a forehead electrode (at Fpx) after impedance analysis. Inter-subject variability in in-ear electrode impedance ranged from 20 kΩ to 25 kΩ at 10 Hz. Signal quality was comparable with an SNR of 6 for in-ear and 8 for forehead electrodes. Alpha attenuation was significant during the eyes-open condition in all in-ear electrodes, and it followed the structure of power spectral density plots of forehead electrodes, with the Pearson correlation coefficient of 0.92 between in-ear locations ELE (Left Ear Superior) and ERE (Right Ear Superior) and forehead locations, Fp1 and Fp2, respectively. The results indicate that in-ear EEG is an unobtrusive alternative in terms of impedance, signal properties and information content to established forehead EEG.
Aeroux
(2022)
Aeroux ist eine Formstudie über die Gestalt einer Luftschiffgondel. Luftschiffe bzw. Zeppeline werden oft mit dem Unglück der Hindenburg in Lakehurst in Verbindung gebracht. Aeroux versucht diese Assoziation zu überwinden und Luftschiffe in der Gegenwart zu verankern.
Durch die gezielte, psychologisch inspirierte Gestaltung soll Sicherheit und Ruhe vermittelt werden, sollen spezifische Assoziationen geweckt werden, die weg führen von Bildern vergangener Tage eines brennenden Luftschiffs, um so Zeppeline als klimafreundlichere Alternative zum Flugzeug wieder ins Spiel zu bringen.
Aeroux ist ein hybrides Verkehrsmittel, dass in der Lage ist, sowohl Güter als auch Personen in verschiedenen Szenarien zu transportieren. Zeppeline bauchen keine befestigten Landebahnen oder Pisten. Regionen, die über Straßen schwer zugänglich sind, können so in den Warenhandel integriert werden. Gleichermaßen können aber auch Meschen in Regionen befördert werden, die durch Straßen oder Landebahnen nicht oder unzureichend erschlossen sind. Darüber hinaus kann Aeroux ein Ansatz sein die Unverträglichkeit von Fliegen und Klimaschutz aufzulösen.
Nicht zuletzt liegt in der gemächlichen Art der Bewegung ein besonderer Zauber. Reisen könnten einen neuen Charakter erhalten: durch die großen Fensterfronten und die geringe Flughöhe können Landschaften auf der Reise neu wahrgenommen werden, der Weg wird wieder Teil des Reisens.
Die Arbeit ist in erster Linie eine Auseinandersetzung mit der Form. Wie wirkt Form, wie lassen sich Assoziationen wecken, lenken, leiten. Wie kann technischer Anspruch, gesellschaftliche Bedingung, ökologisches Bewusstsein und nicht zuletzt Genuss in einem Objekt resultieren.
Digitale und analoge Fertigung spielen im Zuge der Arbeit ineinander. So entstand das Design der Gondel, nach ersten händischen Skizzen, digital. Das Model der Gondel wurde aus diesen Daten 3D gedruckt und die Darstellung der Traghülle ebenfalls auf Grundlage dieser Daten gelasert.
Aeroux möchte Lust auf alternatives Sehen, Denken und Handeln machen. Es gilt viel zu bewegen.
Altered gastrocnemius contractile behavior in former achilles tendon rupture patients during walking
(2022)
Achilles tendon rupture (ATR) remains associated with functional limitations years after injury. Architectural remodeling of the gastrocnemius medialis (GM) muscle is typically observed in the affected leg and may compensate force deficits caused by a longer tendon. Yet patients seem to retain functional limitations during—low-force—walking gait. To explore the potential limits imposed by the remodeled GM muscle-tendon unit (MTU) on walking gait, we examined the contractile behavior of muscle fascicles during the stance phase. In a cross-sectional design, we studied nine former patients (males; age: 45 ± 9 years; height: 180 ± 7 cm; weight: 83 ± 6 kg) with a history of complete unilateral ATR, approximately 4 years post-surgery. Using ultrasonography, GM tendon morphology, muscle architecture at rest, and fascicular behavior were assessed during walking at 1.5 m⋅s–1 on a treadmill. Walking patterns were recorded with a motion capture system. The unaffected leg served as control. Lower limbs kinematics were largely similar between legs during walking. Typical features of ATR-related MTU remodeling were observed during the stance sub-phases corresponding to series elastic element (SEE) lengthening (energy storage) and SEE shortening (energy release), with shorter GM fascicles (36 and 36%, respectively) and greater pennation angles (8° and 12°, respectively). However, relative to the optimal fascicle length for force production, fascicles operated at comparable length in both legs. Similarly, when expressed relative to optimal fascicle length, fascicle contraction velocity was not different between sides, except at the time-point of peak series elastic element (SEE) length, where it was 39 ± 49% lower in the affected leg. Concomitantly, fascicles rotation during contraction was greater in the affected leg during the whole stance-phase, and architectural gear ratios (AGR) was larger during SEE lengthening. Under the present testing conditions, former ATR patients had recovered a relatively symmetrical walking gait pattern. Differences in seen AGR seem to accommodate the profound changes in MTU architecture, limiting the required fascicle shortening velocity. Overall, the contractile behavior of the GM fascicles does not restrict length- or velocity-dependent force potentials during this locomotor task.
Retinal vessels are similar to cerebral vessels in their structure and function. Moderately low oscillation frequencies of around 0.1 Hz have been reported as the driving force for paravascular drainage in gray matter in mice and are known as the frequencies of lymphatic vessels in humans. We aimed to elucidate whether retinal vessel oscillations are altered in Alzheimer's disease (AD) at the stage of dementia or mild cognitive impairment (MCI). Seventeen patients with mild-to-moderate dementia due to AD (ADD); 23 patients with MCI due to AD, and 18 cognitively healthy controls (HC) were examined using Dynamic Retinal Vessel Analyzer. Oscillatory temporal changes of retinal vessel diameters were evaluated using mathematical signal analysis. Especially at moderately low frequencies around 0.1 Hz, arterial oscillations in ADD and MCI significantly prevailed over HC oscillations and correlated with disease severity. The pronounced retinal arterial vasomotion at moderately low frequencies in the ADD and MCI groups would be compatible with the view of a compensatory upregulation of paravascular drainage in AD and strengthen the amyloid clearance hypothesis.
In der Arbeit »An den Rand gedrängt–Die Marginalisierung unserer Städte« wird anhand des Flächenverbrauchs des ruhenden Verkehrs erörtert, inwieweit der private Pkw die Entwicklung unserer Städte bestimmt. Die Zusammenstellung verschiedener Texte, Raumbeobachtungen und fotografischer Zeitdokumente soll die Problematik und Aktualität des Themas verstärken. Schritt für Schritt sollen die Leser:innen einen neuen Blick auf die eigene Stadt gewinnen und für das Problem der akuten Flächenknappheit sensibilisiert werden. Das Werk versteht sich als Aufruf, unseren Straßenraum zu entkarbonisieren, ihn neu zu entdecken und die möglichen Chancen im Wandel zu erkennen. Dabei geht es zunächst nicht um die Aufzählung von Klimaschäden, die Abschaffung von Parkplätzen oder gar des Autos, sondern um die Auswirkungen, die Parkplätze auf unser Leben haben und vor allem um ihr Potenzial für die Zukunft.
Edge-based and face-based smoothed finite element methods (ES-FEM and FS-FEM, respectively) are modified versions of the finite element method allowing to achieve more accurate results and to reduce sensitivity to mesh distortion, at least for linear elements. These properties make the two methods very attractive. However, their implementation in a standard finite element code is nontrivial because it requires heavy and extensive modifications to the code architecture. In this article, we present an element-based formulation of ES-FEM and FS-FEM methods allowing to implement the two methods in a standard finite element code with no modifications to its architecture. Moreover, the element-based formulation permits to easily manage any type of element, especially in 3D models where, to the best of the authors' knowledge, only tetrahedral elements are used in FS-FEM applications found in the literature. Shape functions for non-simplex 3D elements are proposed in order to apply FS-FEM to any standard finite element.
This work introduces a novel method for the detection of H₂O₂ vapor/aerosol of low concentrations, which is mainly applied in the sterilization of equipment in medical industry. Interdigitated electrode (IDE) structures have been fabricated by means of microfabrication techniques. A differential setup of IDEs was prepared, containing an active sensor element (active IDE) and a passive sensor element (passive IDE), where the former was immobilized with an enzymatic membrane of horseradish peroxidase that is selective towards H₂O₂. Changes in the IDEs’ capacitance values (active sensor element versus passive sensor element) under H₂O₂ vapor/aerosol atmosphere proved the detection in the concentration range up to 630 ppm with a fast response time (<60 s). The influence of relative humidity was also tested with regard to the sensor signal, showing no cross-sensitivity. The repeatability assessment of the IDE biosensors confirmed their stable capacitive signal in eight subsequent cycles of exposure to H₂O₂ vapor/aerosol. Room-temperature detection of H₂O₂ vapor/aerosol with such miniaturized biosensors will allow a future three-dimensional, flexible mapping of aseptic chambers and help to evaluate sterilization assurance in medical industry.