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Determination of household area and number of occupants for residential buildings based on census data and 3D CityGML building models for entire municipalities in Germany
No full textInformation on household areas and the corresponding number of occupants is very important in order to derive realistic demand profiles for water or electricity as part of holistic urban energy modeling. However, this data is usually not available. Therefore, this paper presents a method that uses 3D building models and national census data to derive this information on single-building level for residential buildings. The methodology is validated in three German counties of different population density and geographical location, divided into 141 municipalities. Results show that simulation and statistical data mostly vary between -15 % and +15 %, with highest accuracies for municipalities closest to the national average
Assessing the Practical Benefit of Automated Short-Answer Graders
Get PDFShort-Answer Grading (SAG) is a task where student answers to open questions are automatically graded with the support of Natural Language Processing and Machine Learning (ML), saving manual effort. Two main challenges remain in small-scale testing scenarios: (1) ML models work best given large amounts of manually graded training instances, and (2) published evaluation results for pre-trained models do not translate well to new data sets, making automated grading intransparent for teachers and students. We present a grader evaluation workflow that teachers can use for their individual situation
Structured Digital Writing Lab - Workflow, Application and Evaluation
No full textThe importance of writing and publishing is well understood in the academic world and is gaining importance in business applications as well. Students need to gain corresponding skills during their studies. The process itself can be structured and is repeatable. However, students are not familiar with the process and need some guidance to achieve high quality results. Typical writing seminars may be quite theoretical and do not sufficiently guide the writing in teams, reviewing and publication process. This paper presents the Scientific Workflow Guide SWOFI that can be used to guide collaborative academic writing and publishing in a structured process, which resembles the guided process in lab-based education. The results which have been achieved in different seminars at two different institutions are analyzed and discussed
How Empowerment Can Help to Reduce Change-Related Uncertainty in Young Employees
No full textChange can affect employee work behavior and well-being in a variety of ways. The mediating and moderating factors that produce these effects, however, are not fully understood. This study examines the mediating role of uncertainty on affective commitment and organizational attractiveness and assesses whether psychological empowerment can mitigate the effects of change-related uncertainty. Survey data stems from 971 young German banking sector employees during a change period. Results reveal a negative relationship between change and affective commitment as well as between change and organizational attractiveness, with both relationships mediated by uncertainty. Furthermore, empowerment does not moderate this mediation for affective commitment but does for organizational attractiveness. Thus, there are fewer negative effects of uncertainty on organizational attractiveness when psychological empowerment is high. This has several implications for practice: uncertainty should be counteracted during change processes, for example, through transparent communication, and psychological empowerment should be promoted before and during change processes
Interests of (In)frequent Bike Users: Analysis of Differing Target Groups’ Needs Concerning the RouteMeSafe Application
No full textCycling is an emission-free and healthy mode of transportation. However, the share of cycling in the modal split is still low. Perceived safety during cycling could be a reason for that. The RouteMeSafe application is developed at Stuttgart University of Applied Sciences with the aim of tackling this issue. A safety routing function is supposed to increase the short-term safety of cycling by showing safe paths for cyclists. Long-term safety is supposed to be increased with the feedback function enabling cyclists to share their evaluation of the cycling infrastructure with the city administration. The safety routing function is currently in the design phase and the feedback function in prototype phase. To develop the application user-friendly, target groups for both functions need to be defined and their expectations considered in the development process. Two studies with infrequent and frequent cyclists have been conducted to do so. Study 1, a user experience study based on a student sample, showed that infrequent cyclists could be a target group for the safety routing function and frequent cyclists could be a target group for the feedback function. The latter was confirmed in study 2, a technology acceptance study based on a sample with frequent cyclists of Stuttgart. Future studies on the application should investigate the long-term technology acceptance of the two groups. This could help to find out whether both groups can serve as target groups on the long run
Applied RFID in Logistics Testing RFID technology for its application in the fast-moving consumer goods and apparel industries
No full textIn this chapter, a research-oriented lecture on RFID application in logistics is provided. The chapter explains the theoretical background of UHF RFID and is driven by a user story, based on an industry-like scenario in a food & beverages supply chain. Indeed, the second section of this chapter will deep dive into the user story, allowing the reader to personify a supply chain management consultant into a pilot implementation of RFID technologies in the food & beverages sector. Also, the lecture presented in this chapter is strictly connected with practical lab experience. By means of QR codes,
in fact, readers might be linked to supplementary resources, such as data repositories or even experiments, performed either in batch (i.e. readers specify the experimental settings, and then the experiment is performed and the results are provided at a later time) or remotely (i.e. readers become experimenters by remotely accessing and operating lab resources). When carrying out the lab experience, readers are encouraged to work in groups of 2–4 people to set and/or perform the experiments, and to analyze experimental results. The aim of this group work is to foster cooperative learning, especially when this chapter is adopted in higher or vocational education classes or courses
An Assembly Sequence Planning Framework for Complex Data using General Voronoi Diagram
No full textWe present the first realization of an assembly sequence planning framework for large-scale and complex 3D real-world CAD scenarios. Other than in academic benchmark data sets, in our scenario each assembled part is allowed to contain flexible fastening elements and the number of assembled parts is quite high. With our framework we are able to derive a meaningful assembly priority graph for the parts. Our framework divides the disassembly motion of each part into a NEAR- and a subsequent FAR planning phase and uses existing specialized motion planners for each phase. To reduce the number of unsuccessful motion planning requests we use a general Voronoi diagram graph and a novel collision perceiving method which significantly speed up our framework. At the end, we create an assembly priority graph to indicate which parts must be disassembled before others. In our experiments, we show that our framework is the first one which is able to generate a priority graph for a representative data set from the automotive industry. Moreover, the reported disassembly motions for the individual parts are shorter and can be computed faster than with other state-of-the-art frameworks
Connecting Spatially Separated Laboratory Environments by Combining Virtual and Augmented Reality Technology
No full textThis paper proposes a technical solution to connect an existing Virtual Reality laboratory to a real-world laboratory by combining Augmented Reality glasses (Microsoft HoloLens 2) and a Virtual Reality Headset (HTC Vive Pro) in a single networking application. Furthermore, it investigates educational opportunities and challenges of combining both a virtual and a real lab for higher engineering education
A faster method for the simulation-based parametric optimization of structural shading
No full textOptimal shading provides effective shielding of solar radiation to prevent overheating, while ensuring the use of solar gains. To achieve this goal with structural shading elements, a common method is to find the ideal parameters using time-consuming thermal simulations to evaluate possible shader dimensions. In this paper a new method was developed that requires a single ideal thermal reference simulation. Following the simulation the TRNSYS beam solar preprocessing and simulation processes were used to generate the optimal structural shading parameters instead of just evaluating them. The function of the developed method was demonstrated through the successful application to a single zone model
Assembly Sequence Planning for Complex real-world CAD data
No full textThis work investigates algorithms for digital assembly sequence planning. The focus here is on finding feasible assembly sequences for a real-world data set from the automotive industry. Flexible fastening elements that have to be deformed when being disassembled, a large workspace in which the components are located and a very high number of assembled parts push conventional assembly sequence algorithms to their technical and temporal limits when it comes to real-world data. In three consecutive chapters of this work, we investigate how to push these boundaries into the feasible range, meaning that we are conducting pioneering research into the calculation of feasible assembly sequences for real-world data.
The first part of this thesis presents an approximation of a general Voronoi diagram which subdivides the workspace at the maximum clearance. We combine a common voxel propagation algorithm with a novel memory-saving data structure. We then discuss different ways to extract a general Voronoi diagram graph. This graph is a roadmap which provides a roughly estimated translational disassembly path for assembled parts, called Voronoi path. The second part of this work introduces our new path planner Expansive Voronoi Tree (EVT). For a given part, the EVT searches along the according Voronoi path for a collision-free disassembly path, consisting of arbitrary translations and rotations. Our experiments show that the EVT finds shorter paths more reliably within shorter calculation time than conventional path planning algorithms. In the third part, we present our framework for finding feasible assembly sequences. We are the first to calculate feasible assembly sequences for a real-world data set. By using two new algorithms, we detect parts that are still enclosed, which significantly reduces the number of path planning requests and, in turn, calculation time. Our framework divides the disassembly process for an assembled part into a NEAR- and FAR planning phase. Using the path planner from Hegewald et al. (2022) which is designed for deformable fasteners, we unlock parts in the NEAR range and then, in the FAR planning phase, navigate them to a nearby goal position using our EVT. The disassembly paths found are then presented in our new, informative and easy-to-read Assembly Priority Graph. Compared to other representation methods our graph is compact but also shows a high number of feasible assembly sequences. This graph is the result of the interplay of all previously mentioned findings and thus the final result of this work.In dieser Arbeit werden Algorithmen zur virtuellen Montageplanung untersucht. Der Fokus liegt hierbei auf dem Finden von zulaessigen Montagereihenfolgen fur einen Realdatensatz aus der Automobilbranche. Flexible Befestigungselemente, welche während des Ausbauprozesses deformiert werden mussen, ein großer Arbeitsraum, in dem sich die Bauteile befinden sowie die sehr große Anzahl von Montageteilen bringen die gängigen Montagesequenz-Algorithmen bei Realdaten an ihre technischen und zeitlichen Grenzen. In dieser Arbeit werden diese Grenzen in drei aufeinander aufbauenden Kapiteln zum Machbaren hin verschoben, so dass wir als Erste zul¨assige Montagesequenzen fur Realdaten berechnen koennen. Im ersten Teil der Arbeit wird die Approximation eines general Voronoi diagrams vorgestellt, welches den Arbeitsraum an den Stellen mit maximalem Freiraum unterteilt. Der Voxel-propagierende Algorithmus arbeitet auf unserer neuartigen, Arbeitsspeicher sparenden Datenstruktur. Anschließend diskutieren wir verschiedene Möglichkeiten einen general Voronoi diagram graph zu extrahieren. Dieser Graph wird als Straßennetz interpretiert, welches einen grob geschätzten, translatorischen Ausbaupfad (sogenannter Voronoi Pfad) fur montierte Bauteile liefert. Der zweite Teil der Arbeit stellt unseren neuartigen Pfadplaner Expansive Voronoi Tree (EVT) vor. Dieser sucht fur ein Bauteil anhand seines Voronoi Pfades nach einem kollisionsfreien Ausbaupfad, welcher aus beliebigen Translationen und Rotationen besteht. Unsere Experimente zeigen, dass der EVT schneller und zuverl¨assiger kurzere Pfade findet als gängige
Pfadplanungsalgorithmen. Im dritten Teil stellen wir unser Framework zum Finden von zulässigen Montagesequenzen vor. Wir sind die Ersten, die fur einen Realdatensatz zulässige Montagesequenzen berechnen können. Wir erkennen mit zwei neuartigen Algorithmen aktuell noch eingeschlossene Bauteile, verringern somit die Anzahl von Pfadplanungsanfragen und folglich die Berechnungsdauer enorm. Unser Framework unterteilt den Demontagevorgang von einem montierten Bauteil in einen Nah- und Fernbereich. Wir lösen mit dem fur deformierbare Befestigungselemente ausgelegten Pfadplaner von Hegewald u. a. (2022) Bauteile im Nahbereich und navigieren diese anschließend mittels unserem EVT im Fernbereich zu einer nahegelegenen Zielposition.
Die gefundenen Ausbaupfade werden anschließend in unserem neuartigen, aussagekräftigen und leicht zu lesenden Assembly Priority Graph präsentiert. Verglichen mit gängigen Darstellungsmethoden ist unser Graph kompakt, beinhaltet aber dennoch eine Vielzahl von unterschiedlichen Montagesequenzen. Dieser Graph ist das Resultat
vom Zusammenspiel aller erwähnten Ergebnisse und somit das finale Ergebnis dieser Arbeit