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Die Nachfrage nach flexiblen Arbeitsmodellen und damit Remote Work steigt und wird zunehmend zum Kriterium bei der Jobauswahl. Trotz der vielen Vorteile gibt es in der „Remote-Arbeitswelt“ aber immer noch einige Herausforderungen. Remote Arbeitende haben eine andere, teils nachteilige Erfahrung gegenüber Kollegen vor Ort.
Um dafür eine nutzerzentrierte Lösung zu finden, lag der Fokus bei dieser Arbeit auf den Auswirkungen und Bedürfnissen des arbeitenden Menschen. Basierend hierauf wurde ein Dienstleistungsservice konzipiert. Dieser unterstützt Unternehmen, Selbstständige und Mitarbeitende durch passende Angebote und Dienstleistungen in den Bereichen Ausstattung, Technik, Gesundheit, Corporate Benefits u.Ä. Dies ermöglicht auch Arbeitgebenden Aufgaben auszulagern und die Attraktivität und Konkurrenzfähigkeit auf dem Arbeitsmarkt zu steigern. Das wird zukünftig im „war for digitals talents“ immer wichtiger werden.
The proposed Den Haag Zuidwest district heating system of the city of The Hague consists of a deep doublet in a Jurassic sandstone layer that is designed for a production temperature of 75 °C and a reinjection temperature of 40 °C at a flow rate of 150 m3 h−1. The prediction of reservoir temperature and production behavior is crucial for success of the proposed geothermal doublet. This work presents the results of a study of the important geothermal and geohydrological issues for the doublet design. In the first phase of the study, the influences of the three-dimensional (3D) structures of anticlines and synclines on the temperature field were examined. A comprehensive petrophysical investigation was performed to build a large scale 3D-model of the reservoir. Several bottomhole temperatures (BHTs), as well as petrophysical logs were used to calibrate the model using thermal conductivity measurements on 50 samples from boreholes in different lithological units in the study area. Profiles and cross sections extracted from the calculated temperature field were used to study the temperature in the surrounding areas of the planned doublet. In the second phase of the project, a detailed 3D numerical reservoir model was set up, with the aim of predicting the evolution of the producer and injector temperatures, and the extent of the cooled area around the injector. The temperature model from the first phase provided the boundary conditions for the reservoir model. Hydraulic parameters for the target horizons, such as porosity and permeability, were taken from data available from the nearby exploration wells. The simulation results are encouraging as no significant thermal breakthrough is predicted. For the originally planned location of the producer, the extracted water temperature is predicted to be around 79 °C, with an almost negligible cooling in the first 50 years of production. When the producer is located shallower parts of the reservoir, the yield water temperatures is lower, starting at ≈76 °C and decreasing to ≈74 °C after 50 years of operation. This comparatively larger decrease in temperature with time is caused by the structural feature of the reservoir, namely a higher dip causes the cooler water to easily move downward. In view of the poor reservoir data, the reservoir simulation model is constructed to allow iterative updates using data assimilation during planned drilling, testing, and production phases. Measurements during an 8 h pumping test carried out in late 2010 suggest that a flow rate of 150 m3 h−1 is achievable. Fluid temperatures of 76.5 °C were measured, which is very close to the predicted value.
The methodological discourse of mixed-methods research offers general procedures to combine quantitative and qualitative methods for investigating complex fields of research such as higher education. However, integrating different methods still poses considerable challenges. To move beyond general recommendations for mixed-methods research, this chapter proposes to discuss methodological issues with respect to a particular research domain. Taking current studies on the transition to higher education as an example, the authors first provide an overview of the potentials and limitations of quantitative and qualitative methods in the research domain. Second, they show the need for a conceptual framework grounded in the theory of the research object to guide the integration of different methods and findings. Finally, an example study that investigates transition with regard to the interplay of the individual student and the institutional context serves to illustrate the guiding role of theory. The framework integrates different theoretical perspectives on transition, informs the selection of the research methods, and defines the nexus of the two strands that constitute the mixed-methods design. As the interplay of individual and context is of concern for teaching and learning in general, the example presented may be fruitful for the wider field of higher education research.
The hot spots conjecture is only known to be true for special geometries. This paper shows numerically that the hot spots conjecture can fail to be true for easy to construct bounded domains with one hole. The underlying eigenvalue problem for the Laplace equation with Neumann boundary condition is solved with boundary integral equations yielding a non-linear eigenvalue problem. Its discretization via the boundary element collocation method in combination with the algorithm by Beyn yields highly accurate results both for the first non-zero eigenvalue and its corresponding eigenfunction which is due to superconvergence. Additionally, it can be shown numerically that the ratio between the maximal/minimal value inside the domain and its maximal/minimal value on the boundary can be larger than 1 + 10− 3. Finally, numerical examples for easy to construct domains with up to five holes are provided which fail the hot spots conjecture as well.
The hybrid K+/Ca2+ sensor based on laser scanned silicon transducer for multi-component analysis
(2002)
Rocket engine test facilities and launch pads are typically equipped with a guide tube. Its purpose is to ensure the controlled and safe routing of the hot exhaust gases. In addition, the guide tube induces a suction that effects the nozzle flow, namely the flow separation during transient start-up and shut-down of the engine. A cold flow subscale nozzle in combination with a set of guide tubes was studied experimentally
to determine the main influencing parameters.
This thesis introduces the Integrated Emitter Turn-Off (IETO) Thyristor as a new high-power device. Known state-of-the-art research activities like the Dual GCT, the ETO thyristor and the ICT were presented and critically reviewed. A comparison with commercialized solutions identifies the pros and cons of each type of device family. Based on this analysis, the IETO structure is proposed, covering most benefits of each device class. In particular the combination of a MOS-assisted turn-off with a thyristor-based device allows a voltage-controlled MOS switching and the low on-state voltage of the thyristors. The following synthesis of an IETO device stands on a three-dimensional field of optimization spanned by electric, mechanical and thermal aspects. From an electric point of view, the lowest possible parasitic inductance and resistance within the commutation path are optimization criteria. The mechanical construction has to withstand the required contact pressure of multiple kilo Newtons. Finally, thermal borders limit the maximum average current of the device. FEM simulations covering these three aspects are performed for several design proposals. An IETO prototype is constructed and measurements on various test benches attest thermal, mechanical and electric performance. A local decoupling of the external driver stage and the presspack housing is presented by a cable connection. This separation enables a thermal and mechanical independence, which is advantageous in terms of vibrations and thermal cycles including increased reliability. The electric pulse performance of the prototype device is a factor of 3.1 above today''s solutions. In single-pulse measurements, a current up to 1600 A was successfully turned off at 115°C with an active silicon area of 823 mm². One reason for this increased turn-off capability is the extremely low-inductive construction. Additional functionality of the IETO thyristor like over-current self-protection and defined short-circuit failure state are successfully verified.
The inverse scattering problem for a conductive boundary condition and transmission eigenvalues
(2018)
In this paper, we consider the inverse scattering problem associated with an inhomogeneous media with a conductive boundary. In particular, we are interested in two problems that arise from this inverse problem: the inverse conductivity problem and the corresponding interior transmission eigenvalue problem. The inverse conductivity problem is to recover the conductive boundary parameter from the measured scattering data. We prove that the measured scatted data uniquely determine the conductivity parameter as well as describe a direct algorithm to recover the conductivity. The interior transmission eigenvalue problem is an eigenvalue problem associated with the inverse scattering of such materials. We investigate the convergence of the eigenvalues as the conductivity parameter tends to zero as well as prove existence and discreteness for the case of an absorbing media. Lastly, several numerical and analytical results support the theory and we show that the inside–outside duality method can be used to reconstruct the interior conductive eigenvalues.
The Inverted Rotary Pendulum: Facilitating Practical Teaching in Advanced Control Engineering
(2024)
This paper outlines a practical approach to teach control engineering principles, with an inverted rotary pendulum, serving as an illustrative example. It shows how the pendulum is embedded in an advanced course of control engineering. This approach is incorporated into a flipped-classroom concept, as well as classical teaching concepts, offering students practical experience in control engineering. In addition, the design of the pendulum is shown, using a Raspberry Pi as the target platform for Matlab Simulink. This pendulum can be used in the classroom to evaluate the controller design mentioned above. It is analysed if the use of the pendulum generates a deeper understanding of the learning contents.
Analyzing thermodynamic non-equilibrium processes, like the laminar and turbulent fluid flow, the dissipation is a key parameter with a characteristic minimum condition. That is applied to characterize laminar and turbulent behaviour of the Couette flow, including its transition in both directions. The Couette flow is chosen as the only flow form with constant shear stress over the flow profile, being laminar, turbulent or both. The local dissipation defines quantitative and stable criteria for the transition and the existence of turbulence. There are basic results: The Navier Stokes equations cannot describe the experimental flow profiles of the turbulent Couette flow. But they are used to quantify the dissipation of turbulent fluctuation. The dissipation minimum requires turbulent structures reaching maximum macroscopic dimensions, describing turbulence as a “non-local” phenomenon. At the transition the Couette flow profiles and the shear stress change by a factor ≅ 5 due to a change of the “apparent” turbulent viscosity by a calculated factor ≅ 27. The resulting difference of the laminar and the turbulent profiles results in two different Reynolds numbers and different loci of transition, which are identified by calculation.
The join of a geographical situation display system and a platform independent C2 information system
(2000)
The Last Sketch
(2021)
Das Projekt thematisiert, in Form eines Animationsfilms, den Umgang eines Vaters mit dem Tod seines Kindes
und den Versuch den Weg zurück zu sich selbst und ins Leben zu finden.
Das Ziel war es die Emotionen der Schauspieler in einen Animationsfilm authentisch zu implementieren. Um den Animationsfilm situationsgerecht erzählen zu können, wurde das Verständnis für Trauer in den Vordergrund gestellt.
Dazu wurden digitale Drehs durchgeführt und viele Bereiche der 3D Gestaltung angewendet.
Viele der Betroffenen erleben besonders in den ersten Tagen nach dem Verlust ihres Kindes nicht das notwendige Verständnis für ihre Trauer.
Diese Projektarbeit möchte aufzeigen, wie unterschiedlich Menschen trauern und wie sie sich in ihrer Verschiedenheit verlieren können,
besonders wenn es um das gemeinsame Kind geht.
Wenn ein Kind im Sterben liegt, steht für die Eltern sein Wohlbefinden an erster Stelle. Sie wollen alles richtig machen.
Der Protagonist des Films (Teo) und seine Frau Mia haben jedoch unterschiedliche Vorstellung davon, was das Richtige ist und auch nach dem
Tod ihres Kindes haben sie unterschiedliche Bewältigungsstrategien, um mit diesem Schicksalsschlag umzugehen.
Einer der Gründe, warum 80% der Ehepaare sich nach so einem Schicksalsschlag trennen liegt in genau dieser Problematik, weswegen es wichtig ist, diese Thematik zu beleuchten.
Das Projekt thematisiert das Leben im Hospiz. Diese Arbeit liefert mittels authentischer Fotografien von Räumlichkeiten und Details sowie durch intensive Porträts von drei Bewohnenden einen realistischen Einblick in ein Hospiz. Durch diese Aufnahmen werden die Betrachtenden mit dem Thema „Tod“ konfrontiert und es so diesem Thema näher gebracht, um eventuelle Vorurteile einer solchen Einrichtung gegenüber abzulegen. Innerhalb des Bildbands sieht man Fotografien von Fluren, Dekoration, Räumen und Porträtaufnahmen. Begleitend zu den Porträtfotos der Bewohnenden finden sich im Bildband Berichte der selbigen, über ihre alltäglichen Gedanken im Umgang mit dem bevorstehenden eigenen Lebensende. Im Zuge der Recherche zu diesem Projekt hat außerdem ein ausführliches Interview mit einer Pflegekraft des thematisierten Hospizes dabei geholfen, einen realistischen Einblick in die Arbeit vor Ort zu bekommen.