University of Applied Sciences Emden Leer
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Analysis of Multivariate Encryption Schemes: Application to Dob
No full textIn this paper, we study the effect of two modifications to multivariate public key encryption schemes: internal perturbation (ip), and Q_+. Focusing on the Dob encryption scheme, a construction utilising these modifications, we accurately predict the number of degree fall polynomials produced in a Gröbner basis attack, up to and including degree five. The predictions remain accurate even when fixing variables. Based on this new theory we design a novel attack on the Dob encryption scheme, which breaks Dob using the parameters suggested by its designers
Concept and Case Study for a Generic Simulation as a Digital Shadow to Be Used for Production Optimisation
No full textOptimising an existing production plant is a challenging task for companies. Necessary physical test runs disturb running production processes. Simulation models are one opportunity to limit these physical test runs. This is particularly important since today’s fast and intelligent networking opportunities in production systems are in line with the call of Industry 4.0 for substantial and frequent changes. Creating simulation models for those systems requires high effort and in-depth knowledge of production processes. In the current literature, digital twins promise several advantages for production optimisation and can be used to simulate production systems, which reduce necessary physical test runs and related costs. While most companies are not able to create digital twins yet, companies using enterprise resource planning (ERP) systems have the general capability to create digital shadows. This paper presents a concept and a case study for a generic simulation of production systems in AnyLogic™ to create digital shadows as the first step towards a full digital twin. The generic simulation visualises production systems automatically and displays key performance indicators (KPIs) for the planned production program, using representational state transfer (REST) interfaces to extract product and production data from an ERP system. The case study has been applied in a learning factory of the University of Applied Life Sciences Emden/Leer. The results prove the presented concept of the generic simulation and show the limits and challenges of working with generic simulation models
Anomaly Detection in the Time Series Data from Fehn Pollux Ship with ECO Flettner Rotor
No full textAn ECO Flettner rotor has been installed on board the vessel MV Fehn Pollux to reduce the vessel’s carbon emissions and save fuel. The extent of fuel-saving is assessed using recorded data of apparent wind speed, apparent wind angle, and rotor speed by the vessel’s data acquisition and storage system. However, the data contains anomalies caused by noise, vibration, or errors. Detecting anomalies could help to understand the reason for their occurrence, improve the calculation of energy savings, and increase the accuracy of the trained models. To detect anomalies in apparent wind speed, apparent wind angle, and rotor speed, three anomaly detection approaches are proposed. The paper describes the proposed anomaly detection concepts, and it gives an insight into their implementation process. Additionally, it evaluates proposed anomaly detection capabilities
Social stress and risk of declining cognition: a longitudinal study of men and women in the United States
No full textAbstract
Limited research is available on the relationship between social stress and risk of declining cognition. We sought to examine whether social stress has adverse effects on risk of declining episodic memory and executive functioning in aging individuals. We used data from the MIDUS study, a national probability sample of non-institutionalized, English speaking respondents aged 25–74 living in the 48 contiguous states of the United States. The initial wave (1995) included 4963 non-institutionalized adults aged 32–84 (M = 55, SD = 12.4). We used an analytic sample from MIDUS-II (1996/1997) and MIDUS-III (2013) (n = 1821). The dependent variables are episodic memory and executive functioning, which were assessed with the Brief Test for Cognition (BTACT). The independent variables were social stress variables (subjective social status, family and marital stress, work stress and discrimination). To evaluate episodic memory and executive functioning changes over a time period of 10 years, we estimated adjusted linear regression models. Women report significantly lower subjective social status and more discrimination stress than men across all age groups. Controlling for education and income, age, and baseline episodic memory and executive functioning, lower subjective social status had additional adverse effects on declines in episodic memory in men and women. Marital risk had adverse effects on episodic memory in men but not in women. Daily discrimination had adverse effects on executive functioning on all individuals. Public health strategies should focus on reducing social stress in a socio-ecological perspective. Especially, subjective social status and discrimination stress might be a target for prevention efforts
Which UX Aspects Are Important for a Software Product?: Importance Ratings of UX Aspects for Software Products for Measurement with the UEQ+
No full textQuestionnaires are a popular method to measure User Experience (UX). These UX questionnaires cover different UX aspects with their scales. However, UX includes a huge number of semantically different aspects of a user’s interaction with a product. It is therefore practically impossible to cover all these aspects in a single evaluation study. A researcher must select those UX aspects that are most important to the users of the product under investigation. Some papers examined which UX aspects are important for specific product categories. Participants in these studies rated the importance of UX aspects for different product categories. These categories were described by a category name and several examples for products in this category. In principle, the results of these studies can be used to indicate which UX aspects should be measured for a particular product in the corresponding product category. This is especially useful for modular frameworks, e.g., the UEQ+, that allow to create a questionnaire by selecting the relevant scales from a catalog of predefined scales. In this paper, it is investigated how accurate the UX aspect suggestions derived from category-level studies are for individual products. The results show that the predicted importance of a UX aspect from the category is fairly precise
Development of Scenarios for Modelling of Districts’ Energy Supply and Analysis of Interdependencies between Energy and ICT
No full textThe increasing digital transformation in energy supply systems allows
greater control and possibilities for performance optimization and efficiency.
This is accompanied by increasing complexity of the system, and thus requires
the evaluation of interactions between energy and information and
communication technologies (ICT) involved. One of the goals of the project
“Zukunftslabor Energie” (Future Laboratory “Digitalization Energy”) is to
analyze these interactions in highly integrated digitalized systems for district
energy supply. For this, simulation studies must be conducted to configure
flexibilities. A first step is to define appropriate analysis scenarios. Requirements
for these scenarios, the related models, and one of the considered scenarios are
described in this paper. This allows to discuss the system, its boundaries, its
components, and their interactions. Future research requires an analysis and
discussion of requirement specifications, data collection and treatment, model
construction, model implementation, and model validation
Using artificial intelligence in financial distress: Opportunities and obstacles in the implementation of AI / ML-based methods as early warning tools
No full textThe EU Directive on Restructuring and Insolvency (EU 2019/1023)1 requires Member
States to have an early warning system to allow companies in financial distress to detect distress early (enough) to engage in a restructuring, thereby avoiding insolvency. With the absence of a common model at Member State level, this paper analyses the opportunities for artificial intelligence / machine learning-based methods at a corporate level. It is in a company’s interest to implement a system that will alert the management to the need to take action and prevent a distress situation.
The introduction sets the scene while part two discusses the theoretical framework of artificial intelligence / machine learning-based methods and distinguishes between artificial intelligence / machine learning and prediction models. Part three refers to the goal of the EU Directive on Restructuring and Insolvency for Member States to provide alert mechanisms for companies through financial distress prediction models. In Part four, the opportunities and obstacles are investigated through an empirical study with qualitative data, collected from German experts on the current status of (German) companies with respect to implementing artificial intelligence / machine learning as an early warning tool. The study finds that companies see opportunities for using artificial intelligence / machine learning-based methods as early warning tools. The conclusion summarises that there are obstacles to overcome in order to identify financial irregularities and to provide indications for future action to avoid or prevent financial distress
What Causes the Dependency between Perceived Aesthetics and Perceived Usability?
No full textSeveral studies reported a dependency between perceived beauty and perceived usability of a user interface.
But it is still not fully clear which psychological mechanism is responsible for this dependency. We suggest a new explanation based on the concept of visual clarity. This concept describes the perception of order, alignment and visual complexity. A high visual clarity supports a fast orientation on an interface and creates an impression of simplicity. Thus, visual clarity will impact usability dimensions, like efficiency and learnability.
Visual clarity is also related to classical aesthetics and the fluency effect, thus an impact on the perception of aesthetics is plausible. We present two large studies that show a strong mediator effect of visual clarity on the dependency between perceived aesthetics and perceived usability. These results support the proposed explanation. In addition, we show how visual clarity of a user interface can be evaluated by a new scale embedded in the UEQ+ framework. Construction and first evaluation results of this new scale are described
10.P. Workshop: Mental health of older people
No full textDue to a general health deterioration, decline in functional ability, accumulated stressful events related to loss and bereavement, and unfavorable socio-economic circumstances, older adults are known to be vulnerable to the development of mental health problems, sometimes leading to serious mental disorders. Approximately 20% of adults aged 60 and over, suffer nowadays from a mental or neurological disorder. This problem is possibly even more distinct in the context of the recent Covid-19 pandemic where health protecting measurements like restricting physical and social contact, disproportionally affect the mental health of older people who are already at higher risk of social isolation and loneliness. However, according to the WHO, mental health impairment in older people is still a highly under-identified, and under-estimated public health issue, often surrounded by shame and stigma, which hinders an adequate mental health promoting approach in this population. This workshop wants to contribute to new findings in the role that certain factors can play in protecting and promoting the mental health of older people. Research during circumstances of a crisis, like the Covid-19 pandemic, may reveal new insights in this context, although the long-term effects are not yet clear, and longstanding factors may not be overlooked.
Dr Sunwoo Lee (Czech Republic) performed a large survey about mental health of older adults in 27 European countries and will discuss the important role that resilience and optimism can play in promoting mental health in older adults in the midst of a pandemic crisis.
Dr. Cynthia Engels (France) investigated changes in daily activities and mental health of older adults during the lockdown period in France. She will report about the most important changes found and what it meant for peoples' wellbeing and social contacts.
Prof. Patricia De Vriendt (Belgium) further focused on the daily activities of older men and women during the Covid lockdown in Belgium and discovered a significant gender difference in the extent to which they succeed to engage in meaningful activities during this crisis. She will discuss how crucial this meaning in activities is for older adults to maintain in good mental health.
Finally, Prof. Jutta Lindert (Germany and US) will share the rather surprising findings of a large nationwide study in the United States among older adults showing how daily discrimination is related to impaired cognitive functioning in older men and women. She points to the importance of reducing discrimination, especially when the Covid-crisis is behind us, as an important factor in supporting mental health in this older population
Ich sehe was, was du auch siehst: Über die Möglichkeiten von Augmented und Virtual Reality für die digitale Beteiligung von Bürger:innen in der Bau- und Stadtplanung
No full textDigital Government eröffnet Möglichkeiten, Verwaltungs- und Regierungsprozesse kritisch zu reflektieren und sie entsprechend neu zu denken. Oblagen Bürgerbeteiligungsprozesse in der Vergangenheit zahlreichen Hürden, bietet die e‑Partizipation Möglichkeiten, sie mit modernen Technologien zu verbinden, die eine niedrigschwellige Teilhabe ermöglichen. In dem Forschungsprojekt Take Part, gefördert durch das Bundesministerium für Bildung und Forschung, werden innovative Formen der Beteiligung von Bürger:innen in der Stadt- und Bauplanung mithilfe von Augmented und Virtual Reality (AR und VR) erforscht. Dabei geht es vor allem darum, neue Anreize zu schaffen, Bürger:innen zur Beteiligung zu motivieren und durch diese das Konfliktpotential um Bauprojekte zu reduzieren. Mithilfe der innerhalb von Take Part entwickelten App können Bürger:innen Bauvorhaben diskutieren, Feedback geben oder über sie abstimmen, während sie dabei den Beteiligungsgegenstand anschaulich in AR und VR präsentiert bekommen. Zugleich können auch Initiator:innen mithilfe eines Partizipationsökosystems die Beteiligung im jeweiligen Bauvorhaben konfigurieren, indem sie sowohl vorhandene Module kombinieren und konfigurieren, als auch passende Dienstleistungen, wie beispielsweise 3D-Modellierungen, einkaufen. In diesem Beitrag sollen die konkreten technologischen Entwicklungen (u. a. Outdoor-AR-Tracking und räumlich verankerte Diskussionen), sowie das Partizipationsökosystem (Dienstentwicklungs- und Ausführungsplattform) vorgestellt werden. Erstmalig soll so der entwickelte Prototyp umfassend dargestellt werden. Auf die Herausforderung, eine e‑Partizipations-App zu entwickeln, die die Möglichkeit bietet, verschiedene Interaktionskonzepte ineinander zu integrieren und gleichzeitig eine überzeugende User-Experience bietet, soll ebenfalls eingegangen werden. Anschließend wird das Potenzial einer solchen Lösung für die digitale Mitbestimmung in lokaler Verwaltung vor allem in Bezug auf gesteigerte Vorstellungskraft und Motivation zur Teilhabe für Nutzer:innen diskutiert und in den Kontext der Covid-19 Pandemie gesetzt