Akzeptierte Fassung
Refine
Year of publication
Document Type
- Conference Proceeding (30)
- Article (7)
- Bachelor Thesis (6)
- Other (3)
- Working Paper (3)
- Master's Thesis (1)
- Study Thesis (1)
Is part of the Bibliography
- yes (51) (remove)
Keywords
- Building Information Modeling (2)
- Landschaftsarchitektur (2)
- Quality Management (2)
- Agri-Food Chain (1)
- Akademisierung (1)
- Ambiguity (1)
- Anreizsysteme (1)
- Artificial Intelligence (1)
- Aufnahmequote (1)
- BIM-basierter Bauantrag (1)
Institute
In this paper, we evaluate the application of Bayesian Optimization (BO) to discrete event simulation (DES) models. In a first step, we create a simple model, for which we know the optimal set of parameter values in advance. We implement the model in SimPy, a framework for DES written in Python. We then interpret the simulation model as a black box function subject to optimization. We show that it is possible to find the optimal set of parameter values using the open source library GPyOpt. To enhance our evaluation, we create a second and more complex model. To better handle the complexity of the model, and to add a visual component, we build the second model in Simio, a commercial off-the-shelf simulation modeling tool. To apply BO to a model in Simio, we use the Simio API to write an extension for optimization plug-ins. This extension encapsulates the logic of the BO algorithm, which we deployed as a web service in the cloud.
The fact that simulation models are black box functions with regard to their behavior and the influence of their input parameters makes them an apparent candidate for Bayesian Optimization (BO). Simulation models are multivariable and stochastic, and their behavior is to a large extent unpredictable. In particular, we do not know for sure which input parameters to adjust to maximize (or minimize) the model’s outcome. In addition, the complex models can take a substantial amount of time to run.
Bayesian Optimization is a sequential and self-learning algorithm to optimize black box functions similar to as we find them in simulation models: they contain a set of parameters for which we want to identify the optimal set, they are expensive to evaluate, and they exhibit stochastic noise. BO has proven to efficiently optimize black box functions from varius disciplines. Among those, and most notably, it is successfully applied in machine learning algorithms to optimize hyperparameters.
Background:
The evaluation of somatosensory dysfunction is important for diagnostics and may also have implications for prognosis and management. The current standard to evaluate somatosensory dysfunction is quantitative sensory testing (QST), which is expensive and time consuming. This study describes a low-cost and time-efficient clinical sensory test battery (CST), and evaluates its concurrent validity compared to QST.
Method: Three patient cohorts with carpal tunnel syndrome (CTS, n=86), non-specific neck and arm pain (NSNAP, n=40) and lumbar radicular pain/radiculopathy (LR n=26) were included. The CST consisted of 13 tests, each corresponding to a QST parameter and evaluating a broad spectrum of sensory functions using mechanical and thermal detection and pain thresholds and testing both loss and gain of function. Agreement rate, significance and strength of correlation between CST and QST were calculated.
Results: Several CST parameters (cold and warm detection, cold pain, mechanical detection, mechanical pain for loss of function, pressure pain) were significantly correlated with QST, with a majority demonstrating >60% agreement rates and weak to relatively strong correlations. However, agreement varied among cohorts. Gain of function parameters showed stronger correlation in the CTS and NSNAP cohort, whereas loss of function parameters performed better in the LR cohort. Other CST parameters (vibration detection, heat pain, mechanical pain for gain of function, windup ratio) did not significantly correlate with QST.
Conclusion: Some, but not all tests in the CST battery can detect somatosensory dysfunction as determined with QST. The CST battery may perform better when the somatosensory phenotype is more pronounced.
Unter Enclothed Cognition versteht die Wissenschaft den Einfluss der Kleidung einer Person auf ihre eigenen kognitiven Prozesse. In vergangenen Studien erzielten etwa Pro-band:innen in Arztkitteln höhere Werte bei Konzentrationstests und formell gekleidete Personen beschrieben ihren Charakter mit anderen Adjektiven als Menschen in neutraler Kleidung. Sofern solche intrapersonellen Effekte der eigenen Kleidung auf die mensch-liche Kognition konstant und in verschiedenen Kontexten auftreten sollten, sind sie von Interesse, wann immer Fähigkeiten und Persönlichkeit eines Menschen valide einge-schätzt werden sollen. Dies ist etwa in Personalauswahlverfahren der Fall, weil dort von den Ergebnissen der verwendeten Tests und Fragebögen oft wichtige Personalentschei-dungen abhängen. Um zu untersuchen, inwiefern die Kleidung eines Bewerbers oder ei-ner Bewerberin durch intrapersonelle Effekte die Ergebnisse von Auswahlverfahren be-einflusst, wurde von Mai bis November 2021 ein Laborexperiment mit studentischen 100 Proband:innen im nordwestdeutschen Osnabrück durchgeführt. Dabei wurden die Ver-suchspersonen unter Verhüllung des eigentlichen Studienzwecks entweder einer formel-len (Sakko/Blazer und Hemd/Bluse) oder einer zwanglosen Kleidungskondition (Kapu-zenpullover und Jeans) zugewiesen, in der sie zum Experiment erscheinen sollten. Dort wurden sie verschiedenen Fragebögen und Tests unterzogen. Es zeigte sich weder in der allgemeinen und situationsspezifischen Selbstwirksamkeit noch in Leistungsmotivation, Konzentration und kognitiver Leistung ein Unterschied zwischen formeller und zwang-loser Kleidung. Die vorliegende Arbeit beschreibt den theoretischen Hintergrund und die Methoden der Studie und diskutiert ihre Ergebnisse.
Hintergrund: Instrumentalisten leiden häufig unter spielbedingten (neuro-) muskuloskelettalen Erkrankungen. Diese zeigen sich bei Streichern, wie Violinisten, Bratschisten und Cellisten, am häufigsten in Form von Beschwerden im Oberkörper – insbesondere im Schulter-Nacken-Bereich. Die apparative Bewegungsanalyse hat sich bereits als hilfreich bei der Beurteilung von muskuloskelettalen Erkrankungen und schädlichen Bewegungsmustern erwiesen und wird für die Diagnostik bei funktionellen Störungen empfohlen. Es wurde bereits gezeigt, dass die apparative biomechanische Bewegungsanalyse ein valides und klinisch praktikables Werkzeug für die genaue und objektive Untersuchung von Bewegungen bei Streichern ist, jedoch ist ihr Einsatz in der klinischen Konsultation immer noch sehr unüblich. Aus diesem Grund existiert ein Mangel an gut etablierten Bewegungsanalyse-Protokollen zur Untersuchung funktioneller Störungen bei Streichern unter Einsatz biomechanischer Instrumente in einem klinischen Umfeld wie der Physiotherapie.
Ziel ist es daher, die Entwicklung und Anwendung eines solchen Protokolls vorzustellen für die Beurteilung der funktionellen Spielbewegungen des Oberkörpers bei sowohl hohen als auch tiefen Streichern in einem physiotherapeutischen Umfeld.
Methode: Zunächst wurden auf Basis einer klinischen Fragestellung relevante Symptombereiche und Messparameter bestimmt. Anschließend wurden beteiligte Segmente, Gelenke und Muskeln selektiert. Darauf basierend wurde ein umfassendes (mechanisches) Modell des Oberkörpers sowie die dazugehörigen Koordinatensysteme und Rotationssequenzen definiert. Dies lenkte sowohl die Spezifikation eines speziell angefertigten Marker-Sets sowie fortgeschrittener Ansätze wie zur funktionellen Bestimmung von Gelenkzentren und -achsen, als auch die Auswahl und Platzierung von Oberflächenelektroden. Schließlich wurden Aktivitäten zur Kalibrierung und Untersuchung der Bewegungsfunktion sowie relevante Analyseparameter und deren Darstellungsformen festgelegt.
Die Protokolldurchführung beinhaltet zunächst die Auswahl der zu untersuchenden Segmente, Gelenke und Muskeln ausgehend von einer oder mehreren klinischen (Arbeits-)Hypothesen bzw. von den spezifischen Symptombereichen. Darauf basierend werden die benötigten Marker und Oberflächenelektroden konfiguriert und platziert. Anschließend werden die festgelegten Kalibrierungsmessungen und Bewegungsaufgaben durchgeführt. Schließlich werden die relevanten Ergebnisparameter zur Überprüfung der Hypothesen extrahiert.
Der klinische Einsatz der Methode wird exemplarisch anhand einer Violinistin mit spielbedingten Schmerzen erläutert.
Klinische Implikationen: Die potenzielle Anwendung des vorgestellten Vorgehens ist die intra-individuelle Evaluation von gleichzeitig der Gelenk- als auch der Muskelfunktion bei hohen und tiefen Streichern während der physiotherapeutischen Konsultation. Dies soll sowohl zur Diagnose funktioneller Erkrankungen des Bewegungsapparates in Form einer objektiven, umfassenden und dennoch klinisch praktikablen diagnostischen Untersuchung als auch zum prä-post-interventionellen Vergleich beitragen.
Purpose
Attracting skilled students is an important aim of many cities in a knowledge-based society. This paper focuses on urban factors of attractiveness from a student's perspective and analyses their influence on locational choices of students. The criteria found were also used to evaluate how the City of Osnabrück, Germany, is rated in terms of these criteria and to reveal the greatest discrepancies.
Design / Methodology / Approach
The paper is based on a multi-level empirical research concept, including qualitative and quantitative approaches. A survey of 2,300 students was conducted in Osnabrück on the basis of focus group discussions with students and interviews with various experts such as a neighbourhood manager, an urban planner, a district mayor, a college president, a real estate manager.
Originality/value
To date, little research has been undertaken to empirically examine the specific requirements that German students look for in a place to live and study. According to the author’s present state of knowledge (January 2018), a comparable study has not been done.
The main contribution of this paper is the empirical analysis of what makes cities attractive to students. In contrast to the findings of Richard Florida about the Creative Class, the cleanliness of a city, beautiful city scenery, and attractive apartments are more important to students than cultural offers, interesting job opportunities, or a multicultural population.
Practical Implications
Insights from the empirical survey can both help to analyse important factors in students' decision-making process and provide possible measures that the city stakeholders can take.
Keywords
1. Knowledge-based urban development
2. Mobility decisions by students and skilled professionals
3. Location factors
4. Place branding
Proposed paper: Academic Research Paper
Background:
Contact tracing apps are potentially useful tools for supporting national COVID-19 containment strategies. Various national apps with different technical design features have been commissioned and issued by governments worldwide.
Objective:
Our goal was to develop and propose an item set that was suitable for describing and monitoring nationally issued COVID-19 contact tracing apps. This item set could provide a framework for describing the key technical features of such apps and monitoring their use based on widely available information.
Methods:
We used an open-source intelligence approach (OSINT) to access a multitude of publicly available sources and collect data and information regarding the development and use of contact tracing apps in different countries over several months (from June 2020 to January 2021). The collected documents were then iteratively analyzed via content analysis methods. During this process, an initial set of subject areas were refined into categories for evaluation (ie, coherent topics), which were then examined for individual features. These features were paraphrased as items in the form of questions and applied to information materials from a sample of countries (ie, Brazil, China, Finland, France, Germany, Italy, Singapore, South Korea, Spain, and the United Kingdom [England and Wales]). This sample was purposefully selected; our intention was to include the apps of different countries from around the world and to propose a valid item set that can be relatively easily applied by using an OSINT approach.
Results:
Our OSINT approach and subsequent analysis of the collected documents resulted in the definition of the following five main categories and associated subcategories: (1) background information (open-source code, public information, and collaborators); (2) purpose and workflow (secondary data use and warning process design); (3) technical information (protocol, tracing technology, exposure notification system, and interoperability); (4) privacy protection (the entity of trust and anonymity); and (5) availability and use (release date and the number of downloads). Based on this structure, a set of items that constituted the evaluation framework were specified. The application of these items to the 10 selected countries revealed differences, especially with regard to the centralization of the entity of trust and the overall transparency of the apps’ technical makeup.
Conclusions:
We provide a set of criteria for monitoring and evaluating COVID-19 tracing apps that can be easily applied to publicly issued information. The application of these criteria might help governments to identify design features that promote the successful, widespread adoption of COVID-19 tracing apps among target populations and across national boundaries.
This paper presents an optimized algorithm for estimating static and dynamic gait parameters. We use a marker- and contact-less motion capture system that identifies 20 joints of a person walking along a corridor.
Based on the proposed gait cycle detection basic metrics as walking frequency, step/stride length, and support phases are estimated automatically. Applying a rigid body model, we are capable to calculate static and dynamic gait stability metrics. We conclude with initial results of a clinical study evaluating orthopaedic technical support.
Besides yield reduction weeds have positive effects, like enhancing biodiversity or reducing soil erosion. The aim of the work is to enhance biodiversity without yield losses. In growing season 2021/22 a field experiment with winter triticale was conducted to experience the impact of mechanical weed control, sowing date and sowing rate. Especially hoeing had a positive impact on vegetative growth and grain yield while weed growth was inhibited but weed biodiversity stayed equal or increased. A lower seed rate or an earlier sowing date made in general no difference at flowering or harvesting stage.