University of Applied Sciences Emden Leer
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Trust, Perspicuity, Efficiency: Important UX Aspects to Consider for the Successful Adoption of Collaboration Tools in Organisations
No full textCollaboration tools are heavily used in work, education, and leisure. Yet, what makes a good collaboration tool is not well researched. This study focuses on what users expect of collaboration tools by investigating how they are used and which UX aspects are important to users when using them. In a survey, 184 participants described their use of collaboration tools and then rated the importance of 19 given UX aspects in their specific scenario. Results show that seven UX aspects are almost universally seen as most important. Additionally, five aspects seem to be especially relevant in specific usage domains. It is indicated that the context of use, especially the usage domain, influences which UX aspects are important to users. These results can be used by organisations as a guideline when selecting a collaboration tool suitable for their members in order to successfully adopt a tool
Influence of Demographic Variables and Usage Behaviour on the Perceived User Experience
No full textUsers form an overall impression concerning the user experience (UX) based on their perception of special UX qualities. Therefore, measuring users’ perceptions of these particular UX aspects is essential for determining the UX of a product. The measured hedonic qualities, e.g. stimulation or aesthetics, and pragmatic qualities, e.g. efficiency or learnability, form a suitable overall impression of the perceived user experience of the product. In practice, the measurement of such qualities is often carried out with the help of standardized questionnaires such as the SUS, UMUX, or UEQ. However, the same product sometimes shows large differences in the ratings of different users. It is conceivable that other factors, for example, demographics, usage frequency, or experience with a product, can influence UX ratings. In a previous study (Kollmorgen, Schrepp & Thomaschewski, 2022), the four products Netflix, Microsoft PowerPoint, BigBlueButton, and Zoom were examined for differences in the UX ratings according to such factors. In the present paper, the data set was extended by two additional products of different product categories to deepen and broaden the investigation of the influences of external factors on the perceived UX of products, with a specific focus on their impact on pragmatic and hedonic qualities
Navigating and Manoeuvring of modern Wind powered Ships – Status and Requirements from a legal and practical View
No full textSafe and effective navigating and manoeuvring of ships is an essential part of ship operation. The manoeuvrability of ships under sail differs significantly from engine power driven vessels. Ships purely powered by the wind can hardly predict their manoeuvrability as it depends on varying wind conditions and
the status or mode of the wind propulsion system, e.g. full sails set or sails reefed. If a sailing vessel and an engine powered ship encounter under risk of collision the international regulations to avoid collision (COLREGs) [IMO, 1972] apply a hierarchical order of ship categories and prescribe manoeuvring action to avoid collision guided by the principle that ships with full manoeuvrability have full responsibility whereas ships restricted in their manoeuvrability are relieved as they cannot contribute effectively to avoid collision.
Thus, engine powered vessels have to give way towards sailing vessels. COLREGs take the restricted manoeuvrability of sailing vessels as a fact. Pure sailing vessels have always been part of the shipping fleet and need to be considered for the objective of safe navigation and traffic flow.
Differently, the manoeuvring standards for ships laid down in IMO guideline MSC.137 [IMO, 2002] are addressed to ships of any kind of rudder and propulsion with a length of 100 metres and over, and chemical and gas tankers regardless of the length. It can be assumed that MSC.137 does not consider sailing vessels for their low relevance in commercial shipping. From a regulatory view this could imply that all sailing vessels shall be suited with redundant propulsion to be operated as engine powered vessels. Thus, sailing vessels with engine propulsion can be operated in three different modes: as pure sailing vessels, pure engine powered vessels or as hybrid powered ships. There are no specific regulations and requirements on manoeuvrability of ships operated in these modes nor for the change over from one mode to another. This may turn out to be a “grey zone” for navigators on wind powered vessels of the future.
This paper looks at the manoeuvrability of modern wind powered vessels in regard to regulations and practical requirements for navigation and collision avoidance. The focus is on the applicability of current regulations from the navigator’s view based on the operational experience of first modern wind assisted vessels. The legal gaps that are identified and their situational context may lead to insights and approaches for the revision of relevant rules and regulations, examples are given. The paper presents the kick-off phase of the funded “Cargo Sailing Vessel” ship design study performed by Emden/Leer University of Applied Sciences and their partners. An investigation on the manoeuvrability of wind powered ships under operational conditions is in preparation under the project’s framework
Economic and environmental assessments to support the decision-making process in the offshore wind farm decommissioning projects
No full textThe wind energy sector has experienced a significant expansion during the past two decades. With the current global appetite for the further expansion of offshore wind farms (OWFs) as one of the main renewable energy resources, a vast number of OWFs are expected to enter the decommissioning stage in the near future which may potentially create serious environmental and economic challenges to different countries. Hence, effective decision-making procedures are required to protect the environment, taxpayers, and local communities against the potential economic and environmental impacts of OWF assets at the end of their lifetime. The main contribution of this study is to develop a new approach for the economic and environmental assessments of OWF decommissioning projects based on a bottom-up model. The approach formulates the costs and emissions based on the available data and experience in the field and tries to provide appropriate assumptions to predict the costs and emissions caused by the different decommissioning activities. To validate and show the applicability of the approach, the economic and environmental assessments of two OWF decommissioning case studies in the UK continental shelf are investigated; the Lincs and Gunfleet Sands OWFs. A cost sensitivity analysis is also performed for different duration and vessel/equipment leasing parameters to identify the most sensitive parameters in the OWF decommissioning projects. The study suggests a set of interesting conclusions on the economic and environmental assessments of OWF decommissioning projects that may be beneficial for policymakers, operators, and local communities in the wind energy sector
Patterns for Visualizing the Aesthetic Qualities of Business Processes
No full textThis chapter focuses on how to bring knowledge to life in business processes. It provides an example of metaphor as a product of theorizing—see Table 2.1 in Chap. 2. The chapter applies the metaphor of the atmosphere to describe a different type of business process. The traditional business process is a series of tasks performed in a sequence that has a beginning and an ending. The aesthetic business process is made up of experiences—much like how one experiences the atmosphere—as a result of the elements and conditions present in the business process. Where the traditional business process improves outcomes by linking services or tasks in parallel (e.g., horizontally across different functional departments), focusing on the aesthetic business process improves the overall outcome in different ways, by constructing various “atmospheres,” in particular working on the “thinking” atmosphere (engendering independent thinking in constructing business processes) and the “sensing” atmosphere (feeling what works in a business process). The concept of aesthetic business processes aims to stimulate aesthetic satisfaction in digitalized business processes so that new thinking necessary for business process design becomes possible
Tailoring the Curing Kinetics of NBR-Based Rubber Compounds for Additive Manufacturing of Rod Seals
No full textThe additive manufacturing (AM) of elastomeric parts based on high-viscosity reinforced rubbers has increasingly become a topic of scientific research in recent years. In addition to the viscosity, which is several decades higher during processing than the viscosities of thermoplastics, the flowability of the compound after the printing process and the necessary chemical crosslinking of the printed component play a decisive role in producing an elastic, high-quality, and geometrically stable part. After the first technological achievements using the so-called additive manufacturing of elastomers (AME) process, the knowledge gained has to be transferred first to concrete industrial parts. Therefore, in this study, the cure kinetics of a conventional rubber compound are tailored to match the specific requirements for scorch safety in the additive manufacturing of an industrial 2-component rod seal based on an acrylonitrile butadiene rubber O-ring in combination with a thermoplastic polyurethane as the base body. Experimental tests on a test rig for rod seals demonstrate the functionality of this additively manufactured 2-component rod seal
Simulation Strategy for Fluid-Structure Interaction of a Pre-tensioned Dynamic Seal
No full textAfter their assembly, dynamic seals operate in a highly deformed and, therefore, pre-tensioned configuration. The geometrically enforced elastic pre-stress is essential for the sealing effect, which minimises the fluid passing through the seal gap. When moving, a thin film of the fluid is transported through the seal gap to the opposite side of the seal. The mechanics of this fluid film can be described, for instance, using the Reynolds equation for thin-film flow. However, the Reynolds equation is limited to the thin gap and can hardly be applied outside; the “thin gap assumption” is avoided here. Additionally, the geometry penetration of the undeformed seal leads to a system that cannot be meshed at the start of a coupled fluid-structure simulation. We provide a method for solving this type of system using COMSOL Multiphysics. In the first step, solid body contact builds up the elastic pretension. In the following step, the solid body contact is incrementally replaced by fluid pressure induced by an increasing rod movement. The developed model is capable of describing the full loss of solid body contact. It can be applied to simulate local fluid backflow in the vicinity of the seal gap
Exploring the context of use for voice user interfaces: Toward context-dependent user experience quality testing
No full textVoice user interface (VUI) systems, such as Alexa, Siri, and Google Assistant, are popular and widely available. Still, challenges such as privacy and the ability to have a dialog remain. In the latter example, the user expects a human-like conversation, that is, that the VUI understands the dialog and its context. However, this VUI feature of context-aware interaction is rather error prone. For this reason, we intend to explore the VUI context of use and its impact on interaction, that is, relevant user experience (UX). We see a demand for context-dependent UX measurement because analyzing the context of use and UX assessment are both critical human-centered design (HCD) methods. Therefore, we examine the VUI context of use by asking users about how, where, and for what they use VUIs, as well as their UX and improvement proposals. We interviewed people with disabilities who rely on VUIs and people without disabilities who use VUIs for convenience or fun. We identified VUI context-of-use categories and factors and explored their impacts on relevant UX qualities. Our result is a matrix containing these elements; thus, it provides an overview of the contextual UX of our target group's VUI interaction. We intend to develop a VUI context-of-use conceptual structure in the future based on this matrix, which is needed to create an automated context-dependent UX measurement recommendation tool for VUIs. This conceptual structure could also be useful for automated UX testing in the context of VUI
Shift Toward Value-Based Learning: Applying Agile Approaches in Higher Education
No full textDue to circumstances such as digital teaching during the coronavirus pandemic and the emergence of powerful artificial intelligence tools (e.g., ChatGPT), digitization in higher education has increased rapidly in recent years. For this reason, innovative didactic concepts are being applied, and new teaching methods are being tested. One of these is value-based learning, an approach that aims to develop students’ values alongside specialist knowledge. The objective of this research is to investigate how value-based learning can be implemented in higher education through agile practices and agile values. Thus, we have chosen a multiple case study research method that includes three case studies at different German universities of applied sciences. The results show that the application of agile practices and values varies by context and is individualized. Therefore, we developed a conceptual model that shows how value-based learning can be applied to higher education through agile practices and agile values. This conceptual model shows how courses and modules, as well as students and lecturers, evolve through continuous feedback over the course of a semester. Moreover, it allows students to be taught competencies that enable them to adapt to continuous change