arXiv subjects

Michael Neumann

Publications and source records attributed to Michael Neumann.

At least 37 records · Page 2Linked to original sources

arXiv2023

Navigating Cultural Diversity: Barriers and Potentials in Multicultural Agile Software Development Teams

Context: Social aspects are of high importance for being successful using agile methods in software development. People are influenced by their cultural imprint, as the underlying cultural values are guiding us in how we think and act. Thus, one may assume that in multicultural agile software development teams, cultural characteristics influence the result in terms of quality of the team work and consequently, the product to be delivered. Objective: We aim to identify barriers and potentials that may arise in multicultural agile software development teams to provide valuable strategies for both researchers and practitioners faced with barriers or unrealized potentials of cultural diversity. Method: The study is designed as a single-case study with two units of analysis using a mixed-method design consisting quantitative and qualitative methods. Results: First, our results suggest that the cultural characteristics at the team level need to be analyzed individually in intercultural teams, Second, we identified key potentials regarding cultural characteristics providing key potentials such as a individual team subculture that fits agile values like open communication. Third, we derived strategies supporting the potentials of cultural diversity in agile software development teams. Conclusion: Our findings show, that a deeper understanding of cultural influences in multicultural agile software development teams is needed. Based on the results, we already prepare future work to validate the results in other industries.

cs.SE↗

arXiv2023

Organic molecules as origin of visible-range single photon emission from hexagonal boron nitride and mica

The discovery of room-temperature single-photon emitters (SPEs) hosted by two-dimensional hexagonal boron nitride (2D hBN) has sparked intense research interest. Although emitters in the vicinity of 2 eV have been studied extensively, their microscopic identity has remained elusive. The discussion of this class of SPEs has centered on point defects in the hBN crystal lattice, but none of the candidate defect structures have been able to capture the great heterogeneity in emitter properties that is observed experimentally. Employing a widely used sample preparation protocol but disentangling several confounding factors, we demonstrate conclusively that heterogeneous single-photon emission ~2 eV associated with hBN originates from organic molecules, presumably aromatic fluorophores. The appearance of those SPEs depends critically on the presence of organic processing residues during sample preparation, and emitters formed during heat treatment are not located within the hBN crystal as previously thought, but at the hBN/substrate interface. We further demonstrate that the same class of SPEs can be observed in a different 2D insulator, fluorophlogopite mica.

physics.optics↗

arXiv2023

Spectral signatures of a unique charge density wave in Ta$_2$NiSe$_7$

Charge Density Waves (CDW) are commonly associated with the presence of near-Fermi level states which are separated from others, or "nested", by a wavector of $\mathbf{q}$. Here we use Angle-Resolved Photo Emission Spectroscopy (ARPES) on the CDW material Ta$_2$NiSe$_7$ and identify a total absence of any plausible nesting of states at the primary CDW wavevector $\mathbf{q}$. Nevertheless we observe spectral intensity on replicas of the hole-like valence bands, shifted by a wavevector of $\mathbf{q}$, which appears with the CDW transition. In contrast, we find that there is a possible nesting at $\mathbf{2q}$, and associate the characters of these bands with the reported atomic modulations at $\mathbf{2q}$. Our comprehensive electronic structure perspective shows that the CDW-like transition of Ta$_2$NiSe$_7$ is unique, with the primary wavevector $\mathbf{q}$ being unrelated to any low-energy states, but suggests that the reported modulation at $\mathbf{2q}$, which would plausibly connect low-energy states, might be more important for the overall energetics of the problem.

cond-mat.str-el↗

arXiv2023

Characterizing The Impact of Culture on Agile Methods: The MoCA Model

Agile methods are well-known approaches in software development and used in various settings, which may vary wrt. organizational size, culture, or industrial sector. One important facet for the successful use of agile methods is the strong focus on social aspects. We know, that cultural values influence the behaviour of humans. Thus, an in-depth understanding of the influence of cultural aspects on agile methods is necessary to be able to adapt agile methods to various cultural contexts. In this paper we focus on an enabler to this problem. We want to better understand the influence of cultural factors on agile practices. The core contribution of this paper is MoCA: A model describing the impact of cultural values on agile elements.

cs.SE↗

arXiv2022

Key Challenges with Agile Culture -- A Survey among Practitioners

Context: Within agile transformations, there are a lot of different challenges coming up. One very important but less considered and treated in research are cultural challenges. Although research shows that cultural clashes and general organizational resistance to change are part of the most significant agile adoption barriers. Objective: Thus, our objective is to tackle this field and come up with important contributions for further research. To this end, we want to identify challenges that arise from the interplay between agility and organizational culture. Method: This is done based on an iterative research approach. On the one hand, we gathered qualitative data among our network of agile practitioners. Then, we derived in sum 15 challenges with agile culture. On the other hand, we gathered quantitative data by means of a questionnaire study with 92 participants. Results: We identified 7 key challenges out of the 15 challenges with agile culture. The results that are presented in a conceptual model show a focus on human aspects that we need to deal with more in future. Conclusion: Based on our results, we started deriving future work aspects to do more detailed research on the topic of cultural challenges while transitioning or using agile methods in software development and beyond.

cs.SE↗

arXiv2022

Die Einflüsse von Arbeitsbelastung auf die Arbeitsqualität agiler Software-Entwicklungsteams

Due to the Covid 19 pandemic and the associated effects on the world of work, the burden on employees has been brought into focus. This fact also applies to agile software development teams in many companies due to the extensive switch to remote work. Too high a workload can lead to various negative effects, such as increased sick leave, the well-being of employees, or reduced productivity. It is also known that the workload in knowledge work impacts the quality of the work results. This research article identifies potential factors of the workload of the agile software development team members at Otto GmbH & Co KG. Based on the factors, we present measures to reduce workload and explain our findings, which we have validated in an experiment. Our results show that even small-scale actions, such as the introduction of rest work phases during the working day, lead to positive effects, for example, increased ability to concentrate and how these affect the quality of the work results.

cs.SE↗

arXiv2022

When is Good Good Enough? Context Factors for Good Remote Work of Agile Software Development Teams. The Otto Case

The Covid-19 pandemic led to several challenges in everybody working life. Many companies worldwide enabled comprehensive remote work settings for their employees. Agile Software Development Teams are affected by the switch to remote work as agile methods setting communication and collaboration in focus. The well-being and motivation of software engineers and developers, which impacting their performance, are influenced by specific context factors. This paper aims to analyze identify specific context factors for a good remote work setting. We designed a single case study at a German ecommerce company and conducted an experiment using a gamification approach including eight semi-structured interviews. Our results show, that the agile software development team members to their health. Furthermore, most the team members value the gamification approach to put more focus on physical activities and the health well-being. We discuss several practical implications and provide recommendations for other teams and companies.

cs.SE↗

arXiv2021

How a 4-day Work Week affects Agile Software Development Teams

Context: Agile software development (ASD) sets social aspects like communication and collaboration in focus. Thus, one may assume that the specific work organization of companies impacts the work of ASD teams. A major change in work organization is the switch to a 4-day work week, which some companies investigated in experiments. Also, recent studies show that ASD teams are affected by the switch to remote work since the Covid 19 pandemic outbreak in 2020. Objective: Our study presents empirical findings on the effects on ASD teams operating remote in a 4-day work week organization. Method: We performed a qualitative single case study and conducted seven semi-structured interviews, observed 14 agile practices and screened eight project documents and protocols of agile practices. Results: We found, that the teams adapted the agile method in use due to the change to a 4-day work week environment and the switch to remote work. The productivity of the two ASD teams did not decrease. Although the stress level of the ASD team member increased due to the 4-day work week, we found that the job satisfaction of the individual ASD team members is affected positively. Finally, we point to affects on social facets of the ASD teams. Conclusions: The research community benefits from our results as the current state of research dealing with the effects of a 4-day work week on ASD teams is limited. Also, our findings provide several practical implications for ASD teams working remote in a 4-day work week.

cs.SE↗

arXiv2021

The Integrated List of Agile Practices -- A Tertiary Study

Context: Companies adapt agile methods, practices or artifacts for their use in practice since more than two decades. This adaptions result in a wide variety of described agile practices. For instance, the Agile Alliance lists 75 different practices in its Agile Glossary. This situation may lead to misunderstandings, as agile practices with similar names can be interpreted and used differently. Objective: This paper synthesize an integrated list of agile practices, both from primary and secondary sources. Method: We performed a tertiary study to identify existing overviews and lists of agile practices in the literature. We identified 876 studies, of which 37 were included. Results: The results of our paper show that certain agile practices are listed and used more often in existing studies. Our integrated list of agile practices comprises 38 entries structured in five categories. Contribution: The high number of agile practices and thus, the wide variety increased steadily over the past decades due to the adaption of agile methods. Based on our findings, we present a comprehensive overview of agile practices. The research community benefits from our integrated list of agile practices as a potential basis for future research. Also, practitioners benefit from our findings, as the structured overview of agile practices provides the opportunity to select or adapt practices for their specific needs.

cs.SE↗

arXiv2021

Imagination-enabled Robot Perception

Many of today's robot perception systems aim at accomplishing perception tasks that are too simplistic and too hard. They are too simplistic because they do not require the perception systems to provide all the information needed to accomplish manipulation tasks. Typically the perception results do not include information about the part structure of objects, articulation mechanisms and other attributes needed for adapting manipulation behavior. On the other hand, the perception problems stated are also too hard because -- unlike humans -- the perception systems cannot leverage the expectations about what they will see to their full potential. Therefore, we investigate a variation of robot perception tasks suitable for robots accomplishing everyday manipulation tasks, such as household robots or a robot in a retail store. In such settings it is reasonable to assume that robots know most objects and have detailed models of them. We propose a perception system that maintains its beliefs about its environment as a scene graph with physics simulation and visual rendering. When detecting objects, the perception system retrieves the model of the object and places it at the corresponding place in a VR-based environment model. The physics simulation ensures that object detections that are physically not possible are rejected and scenes can be rendered to generate expectations at the image level. The result is a perception system that can provide useful information for manipulation tasks.

cs.RO↗

arXiv2021

Agile Methods in Higher Education: Adapting and Using eduScrum with Real World Projects

This Innovative Practice Full Paper presents our learnings of the process to perform a Master of Science class with eduScrum integrating real world problems as projects. We prepared, performed, and evaluated an agile educational concept for the new Master of Science program Digital Transformation organized and provided by the department of business computing at the University of Applied Sciences and Arts - Hochschule Hannover in Germany. The course deals with innovative methodologies of agile project management and is attended by 25 students. We performed the class due the summer term in 2019 and 2020 as a teaching pair. The eduScrum method has been used in different educational contexts, including higher education. During the approach preparation, we decided to use challenges, problems, or questions from the industry. Thus, we acquired four companies and prepared in coordination with them dedicated project descriptions. Each project description was refined in the form of a backlog (list of requirements). We divided the class into four eduScrum teams, one team for each project. The subdivision of the class was done randomly. Since we wanted to integrate realistic projects into industry partners' implementation, we decided to adapt the eduScrum approach. The eduScrum teams were challenged with different projects, e.g., analyzing a dedicated phenomenon in a real project or creating a theoretical model for a company's new project management approach. We present our experiences of the whole process to prepare, perform and evaluate an agile educational approach combined with projects from practice. We found, that the students value the agile method using real world problems. The paper contributes to the distribution of methods for higher education teaching in the classroom and distance learning.

cs.SE↗

arXiv2021

Investigating the Utility of Multimodal Conversational Technology and Audiovisual Analytic Measures for the Assessment and Monitoring of Amyotrophic Lateral Sclerosis at Scale

We propose a cloud-based multimodal dialog platform for the remote assessment and monitoring of Amyotrophic Lateral Sclerosis (ALS) at scale. This paper presents our vision, technology setup, and an initial investigation of the efficacy of the various acoustic and visual speech metrics automatically extracted by the platform. 82 healthy controls and 54 people with ALS (pALS) were instructed to interact with the platform and completed a battery of speaking tasks designed to probe the acoustic, articulatory, phonatory, and respiratory aspects of their speech. We find that multiple acoustic (rate, duration, voicing) and visual (higher order statistics of the jaw and lip) speech metrics show statistically significant differences between controls, bulbar symptomatic and bulbar pre-symptomatic patients. We report on the sensitivity and specificity of these metrics using five-fold cross-validation. We further conducted a LASSO-LARS regression analysis to uncover the relative contributions of various acoustic and visual features in predicting the severity of patients' ALS (as measured by their self-reported ALSFRS-R scores). Our results provide encouraging evidence of the utility of automatically extracted audiovisual analytics for scalable remote patient assessment and monitoring in ALS.

eess.AS↗

arXiv2021

Investigations on Audiovisual Emotion Recognition in Noisy Conditions

In this paper we explore audiovisual emotion recognition under noisy acoustic conditions with a focus on speech features. We attempt to answer the following research questions: (i) How does speech emotion recognition perform on noisy data? and (ii) To what extend does a multimodal approach improve the accuracy and compensate for potential performance degradation at different noise levels? We present an analytical investigation on two emotion datasets with superimposed noise at different signal-to-noise ratios, comparing three types of acoustic features. Visual features are incorporated with a hybrid fusion approach: The first neural network layers are separate modality-specific ones, followed by at least one shared layer before the final prediction. The results show a significant performance decrease when a model trained on clean audio is applied to noisy data and that the addition of visual features alleviates this effect.

cs.SD↗

arXiv2020

URoboSim -- An Episodic Simulation Framework for Prospective Reasoning in Robotic Agents

Anticipating what might happen as a result of an action is an essential ability humans have in order to perform tasks effectively. On the other hand, robots capabilities in this regard are quite lacking. While machine learning is used to increase the ability of prospection it is still limiting for novel situations. A possibility to improve the prospection ability of robots is through simulation of imagined motions and the physical results of these actions. Therefore, we present URoboSim, a robot simulator that allows robots to perform tasks as mental simulation before performing this task in reality. We show the capabilities of URoboSim in form of mental simulations, generating data for machine learning and the usage as belief state for a real robot.

cs.AI↗

arXiv2020

ADVISER: A Toolkit for Developing Multi-modal, Multi-domain and Socially-engaged Conversational Agents

We present ADVISER - an open-source, multi-domain dialog system toolkit that enables the development of multi-modal (incorporating speech, text and vision), socially-engaged (e.g. emotion recognition, engagement level prediction and backchanneling) conversational agents. The final Python-based implementation of our toolkit is flexible, easy to use, and easy to extend not only for technically experienced users, such as machine learning researchers, but also for less technically experienced users, such as linguists or cognitive scientists, thereby providing a flexible platform for collaborative research. Link to open-source code: https://github.com/DigitalPhonetics/adviser

cs.CL↗

arXiv2018

Cross-lingual and Multilingual Speech Emotion Recognition on English and French

Research on multilingual speech emotion recognition faces the problem that most available speech corpora differ from each other in important ways, such as annotation methods or interaction scenarios. These inconsistencies complicate building a multilingual system. We present results for cross-lingual and multilingual emotion recognition on English and French speech data with similar characteristics in terms of interaction (human-human conversations). Further, we explore the possibility of fine-tuning a pre-trained cross-lingual model with only a small number of samples from the target language, which is of great interest for low-resource languages. To gain more insights in what is learned by the deployed convolutional neural network, we perform an analysis on the attention mechanism inside the network.

cs.CL↗

arXiv2017

Attentive Convolutional Neural Network based Speech Emotion Recognition: A Study on the Impact of Input Features, Signal Length, and Acted Speech

Speech emotion recognition is an important and challenging task in the realm of human-computer interaction. Prior work proposed a variety of models and feature sets for training a system. In this work, we conduct extensive experiments using an attentive convolutional neural network with multi-view learning objective function. We compare system performance using different lengths of the input signal, different types of acoustic features and different types of emotion speech (improvised/scripted). Our experimental results on the Interactive Emotional Motion Capture (IEMOCAP) database reveal that the recognition performance strongly depends on the type of speech data independent of the choice of input features. Furthermore, we achieved state-of-the-art results on the improvised speech data of IEMOCAP.

cs.CL↗

arXiv1998

Hermitian Positive Semidefinite Matrices Whose Entries Are 0 Or 1 in Modulus

We show that a matrix is a Hermitian positive semidefinite matrix whose nonzero entries have modulus 1 if and only if it similar to a direct sum of all $1's$ matrices and a 0 matrix via a unitary monomial similarity. In particular, the only such nonsingular matrix is the identity matrix and the only such irreducible matrix is similar to an all 1's matrix by means of a unitary diagonal similarity. Our results extend earlier results of Jain and Snyder for the case in which the nonzero entries (actually) equal 1. Our methods of proof, which rely on the so called principal submatrix rank property, differ from the approach used by Jain and Snyder.

math.RA↗