TY - JOUR
A1 - Kossmann, Jan
A1 - Halfpap, Stefan
A1 - Jankrift, Marcel
A1 - Schlosser, Rainer
T1 - Magic mirror in my hand, which is the best in the land?
BT - an experimental evaluation of index selection algorithms
JF - Proceedings of the VLDB Endowment
N2 - Indexes are essential for the efficient processing of database workloads. Proposed solutions for the relevant and challenging index selection problem range from metadata-based simple heuristics, over sophisticated multi-step algorithms, to approaches that yield optimal results. The main challenges are (i) to accurately determine the effect of an index on the workload cost while considering the interaction of indexes and (ii) a large number of possible combinations resulting from workloads containing many queries and massive schemata with possibly thousands of attributes.
In this work, we describe and analyze eight index selection algorithms that are based on different concepts and compare them along different dimensions, such as solution quality, runtime, multi-column support, solution granularity, and complexity. In particular, we analyze the solutions of the algorithms for the challenging analytical Join Order, TPC-H, and TPC-DS benchmarks. Afterward, we assess strengths and weaknesses, infer insights for index selection in general and each approach individually, before we give recommendations on when to use which approach.
Y1 - 2020
U6 - https://doi.org/10.14778/3407790.3407832
SN - 2150-8097
VL - 13
IS - 11
SP - 2382
EP - 2395
PB - Association for Computing Machinery
CY - New York
ER -
TY - JOUR
A1 - Koumarelas, Ioannis
A1 - Jiang, Lan
A1 - Naumann, Felix
T1 - Data preparation for duplicate detection
JF - Journal of data and information quality : (JDIQ)
N2 - Data errors represent a major issue in most application workflows. Before any important task can take place, a certain data quality has to be guaranteed by eliminating a number of different errors that may appear in data. Typically, most of these errors are fixed with data preparation methods, such as whitespace removal. However, the particular error of duplicate records, where multiple records refer to the same entity, is usually eliminated independently with specialized techniques. Our work is the first to bring these two areas together by applying data preparation operations under a systematic approach prior to performing duplicate detection.
Our process workflow can be summarized as follows: It begins with the user providing as input a sample of the gold standard, the actual dataset, and optionally some constraints to domain-specific data preparations, such as address normalization. The preparation selection operates in two consecutive phases. First, to vastly reduce the search space of ineffective data preparations, decisions are made based on the improvement or worsening of pair similarities. Second, using the remaining data preparations an iterative leave-one-out classification process removes preparations one by one and determines the redundant preparations based on the achieved area under the precision-recall curve (AUC-PR). Using this workflow, we manage to improve the results of duplicate detection up to 19% in AUC-PR.
KW - data preparation
KW - data wrangling
KW - record linkage
KW - duplicate detection
KW - similarity measures
Y1 - 2020
U6 - https://doi.org/10.1145/3377878
SN - 1936-1955
SN - 1936-1963
VL - 12
IS - 3
PB - Association for Computing Machinery
CY - New York
ER -
TY - JOUR
A1 - Kossmann, Jan
A1 - Schlosser, Rainer
T1 - Self-driving database systems
BT - a conceptual approach
JF - Distributed and parallel databases
N2 - Challenges for self-driving database systems, which tune their physical design and configuration autonomously, are manifold: Such systems have to anticipate future workloads, find robust configurations efficiently, and incorporate knowledge gained by previous actions into later decisions. We present a component-based framework for self-driving database systems that enables database integration and development of self-managing functionality with low overhead by relying on separation of concerns. By keeping the components of the framework reusable and exchangeable, experiments are simplified, which promotes further research in that area. Moreover, to optimize multiple mutually dependent features, e.g., index selection and compression configurations, we propose a linear programming (LP) based algorithm to derive an efficient tuning order automatically. Afterwards, we demonstrate the applicability and scalability of our approach with reproducible examples.
KW - database systems
KW - self-driving
KW - recursive tuning
KW - workload prediction
KW - robustness
Y1 - 2020
U6 - https://doi.org/10.1007/s10619-020-07288-w
SN - 0926-8782
SN - 1573-7578
VL - 38
IS - 4
SP - 795
EP - 817
PB - Springer
CY - Dordrecht
ER -
TY - JOUR
A1 - Hartung, Niklas
A1 - Borghardt, Jens Markus
T1 - A mechanistic framework for a priori pharmacokinetic predictions of orally inhaled drugs
JF - PLoS Computational Biology : a new community journal
N2 - Author summary
The use of orally inhaled drugs for treating lung diseases is appealing since they have the potential for lung selectivity, i.e. high exposure at the site of action -the lung- without excessive side effects. However, the degree of lung selectivity depends on a large number of factors, including physiochemical properties of drug molecules, patient disease state, and inhalation devices. To predict the impact of these factors on drug exposure and thereby to understand the characteristics of an optimal drug for inhalation, we develop a predictive mathematical framework (a "pharmacokinetic model"). In contrast to previous approaches, our model allows combining knowledge from different sources appropriately and its predictions were able to adequately predict different sets of clinical data. Finally, we compare the impact of different factors and find that the most important factors are the size of the inhaled particles, the affinity of the drug to the lung tissue, as well as the rate of drug dissolution in the lung. In contrast to the common belief, the solubility of a drug in the lining fluids is not found to be relevant. These findings are important to understand how inhaled drugs should be designed to achieve best treatment results in patients.
The fate of orally inhaled drugs is determined by pulmonary pharmacokinetic processes such as particle deposition, pulmonary drug dissolution, and mucociliary clearance. Even though each single process has been systematically investigated, a quantitative understanding on the interaction of processes remains limited and therefore identifying optimal drug and formulation characteristics for orally inhaled drugs is still challenging. To investigate this complex interplay, the pulmonary processes can be integrated into mathematical models. However, existing modeling attempts considerably simplify these processes or are not systematically evaluated against (clinical) data. In this work, we developed a mathematical framework based on physiologically-structured population equations to integrate all relevant pulmonary processes mechanistically. A tailored numerical resolution strategy was chosen and the mechanistic model was evaluated systematically against data from different clinical studies. Without adapting the mechanistic model or estimating kinetic parameters based on individual study data, the developed model was able to predict simultaneously (i) lung retention profiles of inhaled insoluble particles, (ii) particle size-dependent pharmacokinetics of inhaled monodisperse particles, (iii) pharmacokinetic differences between inhaled fluticasone propionate and budesonide, as well as (iv) pharmacokinetic differences between healthy volunteers and asthmatic patients. Finally, to identify the most impactful optimization criteria for orally inhaled drugs, the developed mechanistic model was applied to investigate the impact of input parameters on both the pulmonary and systemic exposure. Interestingly, the solubility of the inhaled drug did not have any relevant impact on the local and systemic pharmacokinetics. Instead, the pulmonary dissolution rate, the particle size, the tissue affinity, and the systemic clearance were the most impactful potential optimization parameters. In the future, the developed prediction framework should be considered a powerful tool for identifying optimal drug and formulation characteristics.
Y1 - 2020
U6 - https://doi.org/10.1371/journal.pcbi.1008466
SN - 1553-734X
SN - 1553-7358
VL - 16
IS - 12
PB - PLoS
CY - San Fransisco
ER -
TY - JOUR
A1 - Bludau, Mark-Jan
A1 - Brüggemann, Viktoria
A1 - Busch, Anke
A1 - Dörk, Marian
T1 - Reading traces
BT - scalable exploration in elastic visualizations of cultural heritage data
JF - Computer graphics forum : journal of the European Association for Computer Graphics
N2 - Through a design study, we develop an approach to data exploration that utilizes elastic visualizations designed to support varying degrees of detail and abstraction. Examining the notions of scalability and elasticity in interactive visualizations, we introduce a visualization of personal reading traces such as marginalia or markings inside the reference library of German realist author Theodor Fontane. To explore such a rich and extensive collection, meaningful visual forms of abstraction and detail are as important as the transitions between those states. Following a growing research interest in the role of fluid interactivity and animations between views, we are particularly interested in the potential of carefully designed transitions and consistent representations across scales. The resulting prototype addresses humanistic research questions about the interplay of distant and close reading with visualization research on continuous navigation along several granularity levels, using scrolling as one of the main interaction mechanisms. In addition to presenting the design process and resulting prototype, we present findings from a qualitative evaluation of the tool, which suggest that bridging between distant and close views can enhance exploration, but that transitions between views need to be crafted very carefully to facilitate comprehension.
Y1 - 2020
U6 - https://doi.org/10.1111/cgf.13964
SN - 0167-7055
SN - 1467-8659
VL - 39
IS - 3
SP - 77
EP - 87
PB - Wiley
CY - Hoboken
ER -
TY - THES
A1 - Taeumel, Marcel
T1 - Data-driven tool construction in exploratory programming environments
T1 - Datengetriebener Werkzeugbau in explorativen Programmierumgebungen
N2 - This work presents a new design for programming environments that promote the exploration of domain-specific software artifacts and the construction of graphical tools for such program comprehension tasks. In complex software projects, tool building is essential because domain- or task-specific tools can support decision making by representing concerns concisely with low cognitive effort. In contrast, generic tools can only support anticipated scenarios, which usually align with programming language concepts or well-known project domains.
However, the creation and modification of interactive tools is expensive because the glue that connects data to graphics is hard to find, change, and test. Even if valuable data is available in a common format and even if promising visualizations could be populated, programmers have to invest many resources to make changes in the programming environment. Consequently, only ideas of predictably high value will be implemented. In the non-graphical, command-line world, the situation looks different and inspiring: programmers can easily build their own tools as shell scripts by configuring and combining filter programs to process data.
We propose a new perspective on graphical tools and provide a concept to build and modify such tools with a focus on high quality, low effort, and continuous adaptability. That is, (1) we propose an object-oriented, data-driven, declarative scripting language that reduces the amount of and governs the effects of glue code for view-model specifications, and (2) we propose a scalable UI-design language that promotes short feedback loops in an interactive, graphical environment such as Morphic known from Self or Squeak/Smalltalk systems.
We implemented our concept as a tool building environment, which we call VIVIDE, on top of Squeak/Smalltalk and Morphic. We replaced existing code browsing and debugging tools to iterate within our solution more quickly. In several case studies with undergraduate and graduate students, we observed that VIVIDE can be applied to many domains such as live language development, source-code versioning, modular code browsing, and multi-language debugging. Then, we designed a controlled experiment to measure the effect on the time to build tools. Several pilot runs showed that training is crucial and, presumably, takes days or weeks, which implies a need for further research.
As a result, programmers as users can directly work with tangible representations of their software artifacts in the VIVIDE environment. Tool builders can write domain-specific scripts to populate views to approach comprehension tasks from different angles. Our novel perspective on graphical tools can inspire the creation of new trade-offs in modularity for both data providers and view designers.
N2 - Diese Arbeit schlägt einen neuartigen Entwurf für Programmierumgebungen vor, welche den Umgang mit domänenspezifischen Software-Artefakten erleichtern und die Konstruktion von unterstützenden, grafischen Werkzeugen fördern. Werkzeugbau ist in komplexen Software-Projekten ein essentieller Bestandteil, weil spezifische, auf Domäne und Aufgabe angepasste, Werkzeuge relevante Themen und Konzepte klar darstellen und somit effizient zur Entscheidungsfindung beitragen können. Im Gegensatz dazu sind vorhandene, traditionelle Werkzeuge nur an allgemeinen, wiederkehrenden Anforderungen ausgerichtet, welche im Spezialfall Gedankengänge nur unzureichend abbilden können.
Leider sind das Erstellen und Anpassen von interaktiven Werkzeugen teuer, weil die Beschreibungen zwischen Information und Repräsentation nur schwer auffindbar, änderbar und prüfbar sind. Selbst wenn relevante Daten verfügbar und vielversprechende Visualisierungen konfigurierbar sind, müssten Programmierer viele Ressourcen für das Verändern ihrer Programmierumgeben investieren. Folglich können nur Ideen von hohem Wert umgesetzt werden, um diese Kosten zu rechtfertigen. Dabei sieht die Situation in der textuellen Welt der Kommandozeile sehr vielversprechend aus. Dort können Programmierer einfach ihre Werkzeuge in Form von Skripten anpassen und kleine Filterprogramme kombinieren, um Daten zu verarbeiten.
Wir stellen eine neuartige Perspektive auf grafische Werkzeuge vor und vermitteln dafür ein Konzept, um diese Werkzeuge mit geringem Aufwand und in hoher Qualität zu konstruieren. Im Detail beinhaltet das, erstens, eine objekt-orientierte, daten-getriebene, deklarative Skriptsprache, um die Programmierschnittstelle zwischen Information und Repräsentation zu vereinfachen. Zweitens ist dies eine skalierbare Entwurfssprache für Nutzerschnitt-stellen, welche kurze Feedback-Schleifen und Interaktivität kombiniert, wie es in den Umgebungen Self oder Squeak/Smalltalk typisch ist.
Wir haben unser Konzept in Form einer neuartigen Umgebung für Werkzeugbau mit Hilfe von Squeak/Smalltalk und Morphic umgesetzt. Die Umgebung trägt den Namen VIVIDE. Damit konnten wir die bestehenden Werkzeuge von Squeak für Quelltextexploration und ausführung ersetzen, um unsere Lösung kontinuierlich zu verbessern. In mehreren Fallstudien mit Studenten konnten wir beobachten, dass sich VIVIDE in vielen Domänen anwenden lässt: interaktive Entwicklung von Programmiersprachen, modulare Versionierung und Exploration von Quelltext und Fehleranalyse von mehrsprachigen Systemen. Mit Blick auf zukünftige Forschung haben wir ebenfalls ein kontrolliertes Experiment entworfen. Nach einigen Testläufen stellte sich die Trainingsphase von VIVIDE als größte, und somit offene, Herausforderung heraus.
Im Ergebnis sind wir davon überzeugt, dass Programmierer in VIVIDE direkt mit greifbaren, interaktiven Darstellungen relevanter Software-Artefakte arbeiten können. Im Rahmen des Werkzeugbaus können Programmierer kompakte, angepasste Skripte schreiben, die Visualisierungen konfigurieren, um Programmieraufgaben spezifisch aus mehreren Blickwinkeln zu betrachten. Unsere neuartige Perspektive auf grafische Werkzeuge kann damit sowohl das Bereitstellen von Informationen, als auch den Entwurf interaktiver Grafik positiv beeinflussen.
KW - programming
KW - tool building
KW - user interaction
KW - exploration
KW - liveness
KW - immediacy
KW - direct manipulation
KW - scripting languages
KW - Squeak/Smalltalk
KW - Programmieren
KW - Werkzeugbau
KW - Nutzerinteraktion
KW - Exploration
KW - Lebendigkeit
KW - Direkte Manipulation
KW - Skriptsprachen
KW - Squeak/Smalltalk
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-444289
ER -
TY - JOUR
A1 - Hollmann, Susanne
A1 - Frohme, Marcus
A1 - Endrullat, Christoph
A1 - Kremer, Andreas
A1 - D’Elia, Domenica
A1 - Regierer, Babette
A1 - Nechyporenko, Alina
T1 - Ten simple rules on how to write a standard operating procedure
JF - PLOS Computational Biology
N2 - Research publications and data nowadays should be publicly available on the internet and, theoretically, usable for everyone to develop further research, products, or services. The long-term accessibility of research data is, therefore, fundamental in the economy of the research production process. However, the availability of data is not sufficient by itself, but also their quality must be verifiable. Measures to ensure reuse and reproducibility need to include the entire research life cycle, from the experimental design to the generation of data, quality control, statistical analysis, interpretation, and validation of the results. Hence, high-quality records, particularly for providing a string of documents for the verifiable origin of data, are essential elements that can act as a certificate for potential users (customers). These records also improve the traceability and transparency of data and processes, therefore, improving the reliability of results. Standards for data acquisition, analysis, and documentation have been fostered in the last decade driven by grassroot initiatives of researchers and organizations such as the Research Data Alliance (RDA). Nevertheless, what is still largely missing in the life science academic research are agreed procedures for complex routine research workflows. Here, well-crafted documentation like standard operating procedures (SOPs) offer clear direction and instructions specifically designed to avoid deviations as an absolute necessity for reproducibility. Therefore, this paper provides a standardized workflow that explains step by step how to write an SOP to be used as a starting point for appropriate research documentation.
Y1 - 2020
VL - 16
IS - 9
PB - PLOS
CY - San Francisco
ER -
TY - JOUR
A1 - Chauhan, Ankit
A1 - Friedrich, Tobias
A1 - Rothenberger, Ralf
T1 - Greed is good for deterministic scale-free networks
JF - Algorithmica : an international journal in computer science
N2 - Large real-world networks typically follow a power-law degree distribution. To study such networks, numerous random graph models have been proposed. However, real-world networks are not drawn at random. Therefore, Brach et al. (27th symposium on discrete algorithms (SODA), pp 1306-1325, 2016) introduced two natural deterministic conditions: (1) a power-law upper bound on the degree distribution (PLB-U) and (2) power-law neighborhoods, that is, the degree distribution of neighbors of each vertex is also upper bounded by a power law (PLB-N). They showed that many real-world networks satisfy both properties and exploit them to design faster algorithms for a number of classical graph problems. We complement their work by showing that some well-studied random graph models exhibit both of the mentioned PLB properties. PLB-U and PLB-N hold with high probability for Chung-Lu Random Graphs and Geometric Inhomogeneous Random Graphs and almost surely for Hyperbolic Random Graphs. As a consequence, all results of Brach et al. also hold with high probability or almost surely for those random graph classes. In the second part we study three classical NP-hard optimization problems on PLB networks. It is known that on general graphs with maximum degree Delta, a greedy algorithm, which chooses nodes in the order of their degree, only achieves a Omega (ln Delta)-approximation forMinimum Vertex Cover and Minimum Dominating Set, and a Omega(Delta)-approximation forMaximum Independent Set. We prove that the PLB-U property with beta>2 suffices for the greedy approach to achieve a constant-factor approximation for all three problems. We also show that these problems are APX-hard even if PLB-U, PLB-N, and an additional power-law lower bound on the degree distribution hold. Hence, a PTAS cannot be expected unless P = NP. Furthermore, we prove that all three problems are in MAX SNP if the PLB-U property holds.
KW - random graphs
KW - deterministic properties
KW - power-law
KW - approximation
KW - APX-hardness
Y1 - 2020
U6 - https://doi.org/10.1007/s00453-020-00729-z
SN - 0178-4617
SN - 1432-0541
VL - 82
IS - 11
SP - 3338
EP - 3389
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Barkowsky, Matthias
A1 - Giese, Holger
T1 - Hybrid search plan generation for generalized graph pattern matching
JF - Journal of logical and algebraic methods in programming
N2 - In recent years, the increased interest in application areas such as social networks has resulted in a rising popularity of graph-based approaches for storing and processing large amounts of interconnected data. To extract useful information from the growing network structures, efficient querying techniques are required.
In this paper, we propose an approach for graph pattern matching that allows a uniform handling of arbitrary constraints over the query vertices. Our technique builds on a previously introduced matching algorithm, which takes concrete host graph information into account to dynamically adapt the employed search plan during query execution. The dynamic algorithm is combined with an existing static approach for search plan generation, resulting in a hybrid technique which we further extend by a more sophisticated handling of filtering effects caused by constraint checks. We evaluate the presented concepts empirically based on an implementation for our graph pattern matching tool, the Story Diagram Interpreter, with queries and data provided by the LDBC Social Network Benchmark. Our results suggest that the hybrid technique may improve search efficiency in several cases, and rarely reduces efficiency.
KW - graph pattern matching
KW - search plan generation
Y1 - 2020
U6 - https://doi.org/10.1016/j.jlamp.2020.100563
SN - 2352-2208
VL - 114
PB - Elsevier
CY - New York
ER -
TY - JOUR
A1 - Hacker, Philipp
A1 - Krestel, Ralf
A1 - Grundmann, Stefan
A1 - Naumann, Felix
T1 - Explainable AI under contract and tort law
BT - legal incentives and technical challenges
JF - Artificial intelligence and law
N2 - This paper shows that the law, in subtle ways, may set hitherto unrecognized incentives for the adoption of explainable machine learning applications. In doing so, we make two novel contributions. First, on the legal side, we show that to avoid liability, professional actors, such as doctors and managers, may soon be legally compelled to use explainable ML models. We argue that the importance of explainability reaches far beyond data protection law, and crucially influences questions of contractual and tort liability for the use of ML models. To this effect, we conduct two legal case studies, in medical and corporate merger applications of ML. As a second contribution, we discuss the (legally required) trade-off between accuracy and explainability and demonstrate the effect in a technical case study in the context of spam classification.
KW - explainability
KW - explainable AI
KW - interpretable machine learning
KW - contract
KW - law
KW - tort law
KW - explainability-accuracy trade-off
KW - medical malpractice
KW - corporate takeovers
Y1 - 2020
U6 - https://doi.org/10.1007/s10506-020-09260-6
SN - 0924-8463
SN - 1572-8382
VL - 28
IS - 4
SP - 415
EP - 439
PB - Springer
CY - Dordrecht
ER -
TY - JOUR
A1 - Bordihn, Henning
A1 - Vaszil, György
T1 - Deterministic Lindenmayer systems with dynamic control of parallelism
JF - International journal of foundations of computer science
N2 - M-rate 0L systems are interactionless Lindenmayer systems together with a function assigning to every string a set of multisets of productions that may be applied simultaneously to the string. Some questions that have been left open in the forerunner papers are examined, and the computational power of deterministic M-rate 0L systems is investigated, where also tabled and extended variants are taken into consideration.
KW - parallel rewriting
KW - Lindenmayer systems
KW - restricted parallelism
KW - determinism
KW - developmental systems
KW - formal languages
Y1 - 2019
U6 - https://doi.org/10.1142/S0129054120400031
SN - 0129-0541
SN - 1793-6373
VL - 31
IS - 1
SP - 37
EP - 51
PB - World Scientific
CY - Singapore
ER -
TY - JOUR
A1 - Lambers, Leen
A1 - Weber, Jens
T1 - Preface to the special issue on the 11th International Conference on Graph Transformation
JF - Journal of Logical and Algebraic Methods in Programming
N2 - This special issue contains extended versions of four selected papers from the 11th International Conference on Graph Transformation (ICGT 2018). The articles cover a tool for computing core graphs via SAT/SMT solvers (graph language definition), graph transformation through graph surfing in reaction systems (a new graph transformation formalism), the essence and initiality of conflicts in M-adhesive transformation systems, and a calculus of concurrent graph-rewriting processes (theory on conflicts and parallel independence).
KW - graph transformation
KW - graph languages
KW - conflicts and dependencies in
KW - concurrent graph rewriting
Y1 - 2020
U6 - https://doi.org/10.1016/j.jlamp.2020.100525
SN - 2352-2208
VL - 112
PB - Elsevier
CY - Amsterdam
ER -
TY - BOOK
A1 - Scherbaum, Frank
A1 - Mzhavanadze, Nana
A1 - Arom, Simha
A1 - Rosenzweig, Sebastian
A1 - Müller, Meinard
ED - Scherbaum, Frank
T1 - Tonal Organization of the Erkomaishvili Dataset: Pitches, Scales, Melodies and Harmonies
T3 - Computational Analysis Of Traditional Georgian Vocal Music
N2 - In this study we examine the tonal organization of a series of recordings of liturgical chants, sung in 1966 by the Georgian master singer Artem Erkomaishvili. This dataset is the oldest corpus of Georgian chants from which the time synchronous F0-trajectories for all three voices have been reliably determined (Müller et al. 2017). It is therefore of outstanding importance for the understanding of the tuning principles of traditional Georgian vocal music.
The aim of the present study is to use various computational methods to analyze what these recordings can contribute to the ongoing scientific dispute about traditional Georgian tuning systems. Starting point for the present analysis is the re-release of the original audio data together with estimated fundamental frequency (F0) trajectories for each of the three voices, beat annotations, and digital scores (Rosenzweig et al. 2020). We present synoptic models for the pitch and the harmonic interval distributions, which are the first of such models for which the complete Erkomaishvili dataset was used. We show that these distributions can be very compactly be expressed as Gaussian mixture models, anchored on discrete sets of pitch or interval values for the pitch and interval distributions, respectively. As part of our study we demonstrate that these pitch values, which we refer to as scale pitches, and which are determined as the mean values of the Gaussian mixture elements, define the scale degrees of the melodic sound scales which build the skeleton of Artem Erkomaishvili’s intonation. The observation of consistent pitch bending of notes in melodic phrases, which appear in identical form in a group of chants, as well as the observation of harmonically driven intonation adjustments, which are clearly documented for all pure harmonic intervals, demonstrate that Artem Erkomaishvili intentionally deviates from the scale pitch skeleton quite freely. As a central result of our study, we proof that this melodic freedom is always constrained by the attracting influence of the scale pitches. Deviations of the F0-values of individual note events from the scale pitches at one instance of time are compensated for in the subsequent melodic steps. This suggests a deviation-compensation mechanism at the core of Artem Erkomaishvili’s melody generation, which clearly honors the scales but still allows for a large degree of melodic flexibility. This model, which summarizes all partial aspects of our analysis, is consistent with the melodic scale models derived from the observed pitch distributions, as well as with the melodic and harmonic interval distributions. In addition to the tangible results of our work, we believe that our work has general implications for the determination of tuning models from audio data, in particular for non-tempered music.
T3 - Computational Analysis Of Traditional Georgian Vocal Music - 1
KW - computational ethnomusicology
KW - traditional Georgian music
KW - Georgian chant
KW - Artem Erkomaishvili
KW - musical scales
KW - computergestützte Musikethnologie
KW - traditionelle Georgische Musik
KW - Georgische liturgische Gesänge
KW - Artem Erkomaishvili
KW - musikalische Tonleitern
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-476141
SN - 2702-2641
IS - 1
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - JOUR
A1 - Teichmann, Malte
A1 - Ullrich, André
A1 - Wenz, Julian
A1 - Gronau, Norbert
T1 - Herausforderungen und Handlungsempfehlungen betrieblicher Weiterbildungspraxis in Zeiten der Digitalisierung
T1 - Challenges and recommended actions for in-company vocational training in times of digitization
JF - HMD Praxis der Wirtschaftsinformatik
N2 - Die Digitalisierung von Produktionsprozessen schreitet mit einer hohen Intensität voran. Weiterbildung hat eine hohe Relevanz für betriebliche Transformationsprozesse. Die betriebliche Weiterbildungspraxis ist den aktuellen Herausforderungen der Digitalisierung jedoch nicht gewachsen. Herausforderungen sind Kompetenzlücken der Mitarbeiter, ungewisse Anforderungsprofile und Tätigkeitstypen, demographischer Wandel sowie veraltete didaktische Ansätze. Zudem wird bestehender inhaltlicher und pädagogischer Freiraum bei der Gestaltung von Weiterbildung oftmals nur unzureichend ausgenutzt. Die skizzierte Situation führt dazu, dass der Mehrwert gegenwärtiger Qualifizierungsangebote sowohl für Unternehmen als auch Beschäftigte nicht ausgeschöpft wird. Ausgehend von Veränderungen durch Digitalisierung in der Produktion und deren Auswirkungen auf die Kompetenzentwicklung diskutiert dieser Beitrag Herausforderungen gegenwärtiger betrieblicher Weiterbildung. Er leitet Handlungsempfehlungen ab, die mithilfe von Beispielen gewerkschaftlich unterstützter Weiterbildungspraxis illustriert werden. Im Ergebnis erhalten Interessierte einen Überblick über gegenwärtige Herausforderungen und Handlungsempfehlungen für die Gestaltung und Durchführung von Weiterbildung in Zeiten der Digitalisierung.
N2 - The digital transformation of production processes is constantly progressing. The human workforce is a central success factor, but employees must be prepared for the requirements induced by change, using inter alia competence development. In reality, however, the content-related and pedagogical freedom to design vocational training is often inadequately addressed. Based on the changes trough digitization in production processes, the challenges of current continuing vocational training in enterprises are discussed. Recommendations for action are then derived and illustrated by examples. The recommendations for action can serve as a basis for the design and implementation of their further vocational training practice.
KW - betriebliche Weiterbildungspraxis
KW - Digitalisierung von Produktionsprozessen
KW - gewerkschaftlich unterstützte Weiterbildungspraxis
KW - Kompetenzentwicklung
KW - vocational training
KW - digitization of production processes
KW - labour union education
KW - competence development
Y1 - 2020
U6 - https://doi.org/10.1365/s40702-020-00614-x
SN - 1436-3011
SN - 2198-2775
VL - 57
SP - 512
EP - 527
PB - Springer Vieweg
CY - Wiesbaden
ER -
TY - GEN
A1 - Hollmann, Susanne
A1 - Frohme, Marcus
A1 - Endrullat, Christoph
A1 - Kremer, Andreas
A1 - D’Elia, Domenica
A1 - Regierer, Babette
A1 - Nechyporenko, Alina
T1 - Ten simple rules on how to write a standard operating procedure
T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2 - Research publications and data nowadays should be publicly available on the internet and, theoretically, usable for everyone to develop further research, products, or services. The long-term accessibility of research data is, therefore, fundamental in the economy of the research production process. However, the availability of data is not sufficient by itself, but also their quality must be verifiable. Measures to ensure reuse and reproducibility need to include the entire research life cycle, from the experimental design to the generation of data, quality control, statistical analysis, interpretation, and validation of the results. Hence, high-quality records, particularly for providing a string of documents for the verifiable origin of data, are essential elements that can act as a certificate for potential users (customers). These records also improve the traceability and transparency of data and processes, therefore, improving the reliability of results. Standards for data acquisition, analysis, and documentation have been fostered in the last decade driven by grassroot initiatives of researchers and organizations such as the Research Data Alliance (RDA). Nevertheless, what is still largely missing in the life science academic research are agreed procedures for complex routine research workflows. Here, well-crafted documentation like standard operating procedures (SOPs) offer clear direction and instructions specifically designed to avoid deviations as an absolute necessity for reproducibility. Therefore, this paper provides a standardized workflow that explains step by step how to write an SOP to be used as a starting point for appropriate research documentation.
T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1201
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-525877
SN - 1866-8372
IS - 9
ER -
TY - THES
A1 - Risch, Julian
T1 - Reader comment analysis on online news platforms
N2 - Comment sections of online news platforms are an essential space to express opinions and discuss political topics. However, the misuse by spammers, haters, and trolls raises doubts about whether the benefits justify the costs of the time-consuming content moderation. As a consequence, many platforms limited or even shut down comment sections completely. In this thesis, we present deep learning approaches for comment classification, recommendation, and prediction to foster respectful and engaging online discussions. The main focus is on two kinds of comments: toxic comments, which make readers leave a discussion, and engaging comments, which make readers join a discussion. First, we discourage and remove toxic comments, e.g., insults or threats. To this end, we present a semi-automatic comment moderation process, which is based on fine-grained text classification models and supports moderators. Our experiments demonstrate that data augmentation, transfer learning, and ensemble learning allow training robust classifiers even on small datasets. To establish trust in the machine-learned models, we reveal which input features are decisive for their output with attribution-based explanation methods. Second, we encourage and highlight engaging comments, e.g., serious questions or factual statements. We automatically identify the most engaging comments, so that readers need not scroll through thousands of comments to find them. The model training process builds on upvotes and replies as a measure of reader engagement. We also identify comments that address the article authors or are otherwise relevant to them to support interactions between journalists and their readership. Taking into account the readers' interests, we further provide personalized recommendations of discussions that align with their favored topics or involve frequent co-commenters. Our models outperform multiple baselines and recent related work in experiments on comment datasets from different platforms.
N2 - Kommentarspalten von Online-Nachrichtenplattformen sind ein essentieller Ort, um Meinungen zu äußern und politische Themen zu diskutieren. Der Missbrauch durch Trolle und Verbreiter von Hass und Spam lässt jedoch Zweifel aufkommen, ob der Nutzen die Kosten der zeitaufwendigen Kommentarmoderation rechtfertigt. Als Konsequenz daraus haben viele Plattformen ihre Kommentarspalten eingeschränkt oder sogar ganz abgeschaltet. In dieser Arbeit stellen wir Deep-Learning-Verfahren zur Klassifizierung, Empfehlung und Vorhersage von Kommentaren vor, um respektvolle und anregende Online-Diskussionen zu fördern. Das Hauptaugenmerk liegt dabei auf zwei Arten von Kommentaren: toxische Kommentare, die die Leser veranlassen, eine Diskussion zu verlassen, und anregende Kommentare, die die Leser veranlassen, sich an einer Diskussion zu beteiligen. Im ersten Schritt identifizieren und entfernen wir toxische Kommentare, z.B. Beleidigungen oder Drohungen. Zu diesem Zweck stellen wir einen halbautomatischen Moderationsprozess vor, der auf feingranularen Textklassifikationsmodellen basiert und Moderatoren unterstützt. Unsere Experimente zeigen, dass Datenanreicherung, Transfer- und Ensemble-Lernen das Trainieren robuster Klassifikatoren selbst auf kleinen Datensätzen ermöglichen. Um Vertrauen in die maschinell gelernten Modelle zu schaffen, zeigen wir mit attributionsbasierten Erklärungsmethoden auf, welche Teile der Eingabe für ihre Ausgabe entscheidend sind. Im zweiten Schritt ermutigen und markieren wir anregende Kommentare, z.B. ernsthafte Fragen oder sachliche Aussagen.
Wir identifizieren automatisch die anregendsten Kommentare, so dass die Leser nicht durch Tausende von Kommentaren blättern müssen, um sie zu finden. Der Trainingsprozess der Modelle baut auf Upvotes und Kommentarantworten als Maß für die Aktivität der Leser auf.
Wir identifizieren außerdem Kommentare, die sich an die Artikelautoren richten oder anderweitig für sie relevant sind, um die Interaktion zwischen Journalisten und ihrer Leserschaft zu unterstützen. Unter Berücksichtigung der Interessen der Leser bieten wir darüber hinaus personalisierte Diskussionsempfehlungen an, die sich an den von ihnen bevorzugten Themen oder häufigen Diskussionspartnern orientieren. In Experimenten mit Kommentardatensätzen von verschiedenen Plattformen übertreffen unsere Modelle mehrere grundlegende Vergleichsverfahren und aktuelle verwandte Arbeiten.
T2 - Analyse von Leserkommentaren auf Online-Nachrichtenplattformen
KW - machine learning
KW - Maschinelles Lernen
KW - text classification
KW - Textklassifikation
KW - social media
KW - Soziale Medien
KW - hate speech detection
KW - Hasserkennung
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-489222
ER -
TY - JOUR
A1 - Luther, Laura
A1 - Tiberius, Victor
A1 - Brem, Alexander
T1 - User experience (UX) in business, management, and psychology
BT - a bibliometric mapping of the current state of research
JF - Multimodal technologies and interaction : open access journal
N2 - User Experience (UX) describes the holistic experience of a user before, during, and after interaction with a platform, product, or service. UX adds value and attraction to their sole functionality and is therefore highly relevant for firms. The increased interest in UX has produced a vast amount of scholarly research since 1983. The research field is, therefore, complex and scattered. Conducting a bibliometric analysis, we aim at structuring the field quantitatively and rather abstractly. We employed citation analyses, co-citation analyses, and content analyses to evaluate productivity and impact of extant research. We suggest that future research should focus more on business and management related topics.
KW - bibliometric analysis
KW - co-citation analysis
KW - co-occurrence analysis
KW - citation analysis
KW - user experience
KW - UX
Y1 - 2020
U6 - https://doi.org/10.3390/mti4020018
SN - 2414-4088
VL - 4
IS - 2
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Doerr, Benjamin
A1 - Kötzing, Timo
T1 - Multiplicative Up-Drift
JF - Algorithmica
N2 - Drift analysis aims at translating the expected progress of an evolutionary algorithm (or more generally, a random process) into a probabilistic guarantee on its run time (hitting time). So far, drift arguments have been successfully employed in the rigorous analysis of evolutionary algorithms, however, only for the situation that the progress is constant or becomes weaker when approaching the target. Motivated by questions like how fast fit individuals take over a population, we analyze random processes exhibiting a (1+delta)-multiplicative growth in expectation. We prove a drift theorem translating this expected progress into a hitting time. This drift theorem gives a simple and insightful proof of the level-based theorem first proposed by Lehre (2011). Our version of this theorem has, for the first time, the best-possible near-linear dependence on 1/delta} (the previous results had an at least near-quadratic dependence), and it only requires a population size near-linear in delta (this was super-quadratic in previous results). These improvements immediately lead to stronger run time guarantees for a number of applications. We also discuss the case of large delta and show stronger results for this setting.
KW - drift theory
KW - evolutionary computation
KW - stochastic process
Y1 - 2020
U6 - https://doi.org/10.1007/s00453-020-00775-7
SN - 0178-4617
SN - 1432-0541
VL - 83
IS - 10
SP - 3017
EP - 3058
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Ghahremani, Sona
A1 - Giese, Holger
T1 - Evaluation of self-healing systems
BT - An analysis of the state-of-the-art and required improvements
JF - Computers
N2 - Evaluating the performance of self-adaptive systems is challenging due to their interactions with often highly dynamic environments. In the specific case of self-healing systems, the performance evaluations of self-healing approaches and their parameter tuning rely on the considered characteristics of failure occurrences and the resulting interactions with the self-healing actions. In this paper, we first study the state-of-the-art for evaluating the performances of self-healing systems by means of a systematic literature review. We provide a classification of different input types for such systems and analyse the limitations of each input type. A main finding is that the employed inputs are often not sophisticated regarding the considered characteristics for failure occurrences. To further study the impact of the identified limitations, we present experiments demonstrating that wrong assumptions regarding the characteristics of the failure occurrences can result in large performance prediction errors, disadvantageous design-time decisions concerning the selection of alternative self-healing approaches, and disadvantageous deployment-time decisions concerning parameter tuning. Furthermore, the experiments indicate that employing multiple alternative input characteristics can help with reducing the risk of premature disadvantageous design-time decisions.
KW - self-healing
KW - failure model
KW - performance
KW - simulation
KW - evaluation
Y1 - 2020
U6 - https://doi.org/10.3390/computers9010016
SN - 2073-431X
VL - 9
IS - 1
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - de Wiljes, Jana
A1 - Pathiraja, Sahani Darschika
A1 - Reich, Sebastian
T1 - Ensemble transform algorithms for nonlinear smoothing problems
JF - SIAM journal on scientific computing
N2 - Several numerical tools designed to overcome the challenges of smoothing in a non-linear and non-Gaussian setting are investigated for a class of particle smoothers. The considered family of smoothers is induced by the class of linear ensemble transform filters which contains classical filters such as the stochastic ensemble Kalman filter, the ensemble square root filter, and the recently introduced nonlinear ensemble transform filter. Further the ensemble transform particle smoother is introduced and particularly highlighted as it is consistent in the particle limit and does not require assumptions with respect to the family of the posterior distribution. The linear update pattern of the considered class of linear ensemble transform smoothers allows one to implement important supplementary techniques such as adaptive spread corrections, hybrid formulations, and localization in order to facilitate their application to complex estimation problems. These additional features are derived and numerically investigated for a sequence of increasingly challenging test problems.
KW - data assimilation
KW - smoother
KW - localization
KW - optimal transport
KW - adaptive
KW - spread correction
Y1 - 2019
U6 - https://doi.org/10.1137/19M1239544
SN - 1064-8275
SN - 1095-7197
VL - 42
IS - 1
SP - A87
EP - A114
PB - Society for Industrial and Applied Mathematics
CY - Philadelphia
ER -
TY - GEN
A1 - Studen, Laura
A1 - Tiberius, Victor
T1 - Social Media, Quo Vadis?
BT - Prospective Development and Implications
T2 - Postprints der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe
N2 - Over the past two decades, social media have become a crucial and omnipresent cultural and economic phenomenon, which has seen platforms come and go and advance technologically. In this study, we explore the further development of social media regarding interactive technologies, platform development, relationships to news media, the activities of institutional and organizational users, and effects of social media on the individual and the society over the next five to ten years by conducting an international, two-stage Delphi study. Our results show that enhanced interaction on platforms, including virtual and augmented reality, somatosensory sense, and touch- and movement-based navigation are expected. AIs will interact with other social media users. Inactive user profiles will outnumber active ones. Platform providers will diversify into the WWW, e-commerce, edu-tech, fintechs, the automobile industry, and HR. They will change to a freemium business model and put more effort into combating cybercrime. Social media will become the predominant news distributor, but fake news will still be problematic. Firms will spend greater amounts of their budgets on social media advertising, and schools, politicians, and the medical sector will increase their social media engagement. Social media use will increasingly lead to individuals’ psychic issues. Society will benefit from economic growth and new jobs, increased political interest, democratic progress, and education due to social media. However, censorship and the energy consumption of platform operators might rise.
T3 - Zweitveröffentlichungen der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe - 131
KW - Delphi study
KW - individual effects
KW - interactive technologies
KW - news media
KW - social media
KW - societal effects
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-482934
SN - 1867-5808
IS - 131
ER -
TY - JOUR
A1 - Studen, Laura
A1 - Tiberius, Victor
T1 - Social Media, Quo Vadis?
BT - Prospective Development and Implications
JF - Future Internet
N2 - Over the past two decades, social media have become a crucial and omnipresent cultural and economic phenomenon, which has seen platforms come and go and advance technologically. In this study, we explore the further development of social media regarding interactive technologies, platform development, relationships to news media, the activities of institutional and organizational users, and effects of social media on the individual and the society over the next five to ten years by conducting an international, two-stage Delphi study. Our results show that enhanced interaction on platforms, including virtual and augmented reality, somatosensory sense, and touch- and movement-based navigation are expected. AIs will interact with other social media users. Inactive user profiles will outnumber active ones. Platform providers will diversify into the WWW, e-commerce, edu-tech, fintechs, the automobile industry, and HR. They will change to a freemium business model and put more effort into combating cybercrime. Social media will become the predominant news distributor, but fake news will still be problematic. Firms will spend greater amounts of their budgets on social media advertising, and schools, politicians, and the medical sector will increase their social media engagement. Social media use will increasingly lead to individuals’ psychic issues. Society will benefit from economic growth and new jobs, increased political interest, democratic progress, and education due to social media. However, censorship and the energy consumption of platform operators might rise.
KW - Delphi study
KW - individual effects
KW - interactive technologies
KW - news media
KW - social media
KW - societal effects
Y1 - 2020
U6 - https://doi.org/10.3390/fi12090146
SN - 1999-5903
VL - 12
IS - 9
PB - MDPI
CY - Basel
ER -
TY - GEN
A1 - Luther, Laura
A1 - Tiberius, Victor
A1 - Brem, Alexander
T1 - User experience (UX) in business, management, and psychology
BT - a bibliometric mapping of the current state of research
T2 - Postprints der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe
N2 - User Experience (UX) describes the holistic experience of a user before, during, and after interaction with a platform, product, or service. UX adds value and attraction to their sole functionality and is therefore highly relevant for firms. The increased interest in UX has produced a vast amount of scholarly research since 1983. The research field is, therefore, complex and scattered. Conducting a bibliometric analysis, we aim at structuring the field quantitatively and rather abstractly. We employed citation analyses, co-citation analyses, and content analyses to evaluate productivity and impact of extant research. We suggest that future research should focus more on business and management related topics.
T3 - Zweitveröffentlichungen der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe - 136
KW - bibliometric analysis
KW - co-citation analysis
KW - co-occurrence analysis
KW - citation analysis
KW - user experience
KW - UX
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-472534
SN - 1867-5808
IS - 136
ER -
TY - BOOK
A1 - Maximova, Maria
A1 - Schneider, Sven
A1 - Giese, Holger
T1 - Compositional analysis of probabilistic timed graph transformation systems
N2 - The analysis of behavioral models is of high importance for cyber-physical systems, as the systems often encompass complex behavior based on e.g. concurrent components with mutual exclusion or probabilistic failures on demand. The rule-based formalism of probabilistic timed graph transformation systems is a suitable choice when the models representing states of the system can be understood as graphs and timed and probabilistic behavior is important. However, model checking PTGTSs is limited to systems with rather small state spaces.
We present an approach for the analysis of large scale systems modeled as probabilistic timed graph transformation systems by systematically decomposing their state spaces into manageable fragments. To obtain qualitative and quantitative analysis results for a large scale system, we verify that results obtained for its fragments serve as overapproximations for the corresponding results of the large scale system. Hence, our approach allows for the detection of violations of qualitative and quantitative safety properties for the large scale system under analysis. We consider a running example in which we model shuttles driving on tracks of a large scale topology and for which we verify that shuttles never collide and are unlikely to execute emergency brakes. In our evaluation, we apply an implementation of our approach to the running example.
N2 - Die Analyse von Verhaltensmodellen ist für cyber-physikalische Systeme von hoher Bedeutung, da die Systeme häufig komplexes Verhalten umfassen, das z.B. parallele Komponenten mit gegenseitigem Ausschluss oder probabilistischen Fehlern bei Bedarf umfasst. Der regelbasierte Formalismus probabilistischer zeitgesteuerter Graphtransformationssysteme ist eine geeignete Wahl, wenn die Modelle, die Zustände des Systems darstellen, als Graphen verstanden werden können und zeitgesteuertes und probabilistisches Verhalten wichtig ist. Modelchecking von PTGTSs ist jedoch auf Systeme mit relativ kleinen Zustandsräumen beschränkt.
Wir präsentieren einen Ansatz zur Analyse von Großsystemen, die als probabilistische zeitgesteuerte Graphtransformationssysteme modelliert wurden, indem ihre Zustandsräume systematisch in überschaubare Fragmente zerlegt werden. Um qualitative und quantitative Analyseergebnisse für ein Großsystem zu erhalten, überprüfen wir, ob die für seine Fragmente erhaltenen Ergebnisse als Überannäherungen für die entsprechenden Ergebnisse des Großsystems dienen. Unser Ansatz ermöglicht es daher, Verstöße gegen qualitative und quantitative Sicherheitseigenschaften für das untersuchte Großsystem zu erkennen. Wir betrachten ein Beispiel, in dem wir Shuttles modellieren, die auf Gleisen einer großen Topologie fahren, und für die wir überprüfen, dass Shuttles niemals kollidieren und wahrscheinlich keine Notbremsungen ausführen. In unserer Auswertung wenden wir eine Implementierung unseres Ansatzes auf das Beispiel an.
T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 133
KW - cyber-physical systems
KW - graph transformation systems
KW - qualitative analysis
KW - quantitative analysis
KW - probabilistic timed systems
KW - compositional analysis
KW - model checking
KW - Cyber-physikalische Systeme
KW - Graphentransformationssysteme
KW - qualitative Analyse
KW - quantitative Analyse
KW - probabilistische zeitgesteuerte Systeme
KW - Modellprüfung
KW - kompositionale Analyse
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-490131
SN - 978-3-86956-501-9
SN - 1613-5652
SN - 2191-1665
IS - 133
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - JOUR
A1 - von Steinau-Steinrück, Robert
A1 - Beismann, Lukas
T1 - (Corona-)Homeoffice und betriebliche Übung
JF - NJW spezial
N2 - Homeoffice und mobiles Arbeiten haben sich infolge der Covid-19-Pandemie bei vielen Unternehmen bekanntlich etabliert. Die Anweisung bzw. „Duldung“ des Homeoffice beruhte allerdings meist mehr auf tatsächlicher als auf rechtlicher Grundlage. Letztere könnte aber aus betrieblicher Übung erwachsen. Dieser Beitrag geht dem rechtlichen Rahmen dafür nach.
Y1 - 2020
UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-626-N-1
SN - 1613-4621
VL - 17
IS - 20
SP - 626
EP - 627
PB - C.H. Beck
CY - München
ER -
TY - JOUR
A1 - von Steinau-Steinrück, Robert
A1 - Jöris, Nils
T1 - Arbeitsschutz bei Corona
BT - Versuch einer Entwirrung
JF - NJW spezial
N2 - Den Überblick im Arbeitsschutzrecht zu behalten, ist schwierig. Der Arbeitsschutz spielt sich in unterschiedlichen Bereichen und auf verschiedenen Ebenen ab. Außerdem sind die einschlägigen Rechtsnormen überaus verästelt. Der folgende Beitrag soll daher zur Entwirrung beitragen.
Y1 - 2020
UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-370-N-1
SN - 1613-4621
VL - 17
IS - 12
SP - 370
EP - 371
PB - C.H. Beck
CY - München
ER -
TY - GEN
A1 - von Steinau-Steinrück, Robert
T1 - Gesetzesentwurf zu Corona-bedingten Änderungen des ArbGG/SGG
T2 - NJW spezial
Y1 - 2020
UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-340-N-2
SN - 1613-4621
VL - 17
IS - 11
SP - 340
EP - 340
PB - C.H. Beck
CY - München
ER -
TY - GEN
A1 - von Steinau-Steinrück, Robert
T1 - Koalitionsausschuss beschließt Verlängerung des Kurzarbeitergelds
T2 - NJW spezial
Y1 - 2020
UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-596-N-2
SN - 1613-4621
VL - 17
IS - 19
SP - 596
EP - 596
PB - C.H. Beck
CY - München
ER -
TY - BOOK
A1 - Bein, Leon
A1 - Braun, Tom
A1 - Daase, Björn
A1 - Emsbach, Elina
A1 - Matthes, Leon
A1 - Stiede, Maximilian
A1 - Taeumel, Marcel
A1 - Mattis, Toni
A1 - Ramson, Stefan
A1 - Rein, Patrick
A1 - Hirschfeld, Robert
A1 - Mönig, Jens
T1 - SandBlocks
T1 - SandBlocks
BT - Integration visueller und textueller Programmelemente in Live-Programmiersysteme
BT - integration of visual and textual elements in live programming systems
N2 - Visuelle Programmiersprachen werden heutzutage zugunsten textueller Programmiersprachen nahezu nicht verwendet, obwohl visuelle Programmiersprachen einige Vorteile bieten. Diese reichen von der Vermeidung von Syntaxfehlern, über die Nutzung konkreter domänenspezifischer Notation bis hin zu besserer Lesbarkeit und Wartbarkeit des Programms. Trotzdem greifen professionelle Softwareentwickler nahezu ausschließlich auf textuelle Programmiersprachen zurück.
Damit Entwickler diese Vorteile visueller Programmiersprachen nutzen können, aber trotzdem nicht auf die ihnen bekannten textuellen Programmiersprachen verzichten müssen, gibt es die Idee, textuelle und visuelle Programmelemente gemeinsam in einer Programmiersprache nutzbar zu machen. Damit ist dem Entwickler überlassen wann und wie er visuelle Elemente in seinem Programmcode verwendet.
Diese Arbeit stellt das SandBlocks-Framework vor, das diese gemeinsame Nutzung visueller und textueller Programmelemente ermöglicht. Neben einer Auswertung visueller Programmiersprachen, zeigt es die technische Integration visueller Programmelemente in das Squeak/Smalltalk-System auf, gibt Einblicke in die Umsetzung und Verwendung in Live-Programmiersystemen und diskutiert ihre Verwendung in unterschiedlichen Domänen.
N2 - Nowadays, visual programming languages exist but are rarely used because textual languages dominate the field. Even though visual languages can offer many virtues - such as protection from syntax errors, concise notation for specific domains, improved readability and maintainability of programs – professional software developers tend to only employ textual programming languages.
We propose an approach to combine both textual and visual elements in a shared programming system. Developers can rely on the familiar textual representation of source code but also leverage the programming experience with a visual language as needed.
This work presents the SandBlocks framework, which enables a joint experience of visual and textual programming elements. It discusses the virtues of visual languages and related work, describes a technical integration of visual elements into the Squeak/Smalltalk programming system, sketches potential workflows in live programming systems, and illustrates applications for several domains.
T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 132
KW - Programmieren
KW - Benutzerinteraktion
KW - visuelle Sprachen
KW - Liveness
KW - Smalltalk
KW - programming
KW - user interaction
KW - visual languages
KW - liveness
KW - Smalltalk
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-439263
SN - 978-3-86956-482-1
SN - 1613-5652
SN - 2191-1665
IS - 132
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - JOUR
A1 - Torkura, Kennedy A.
A1 - Sukmana, Muhammad Ihsan Haikal
A1 - Cheng, Feng
A1 - Meinel, Christoph
T1 - CloudStrike
BT - chaos engineering for security and resiliency in cloud infrastructure
JF - IEEE access : practical research, open solutions
N2 - Most cyber-attacks and data breaches in cloud infrastructure are due to human errors and misconfiguration vulnerabilities. Cloud customer-centric tools are imperative for mitigating these issues, however existing cloud security models are largely unable to tackle these security challenges. Therefore, novel security mechanisms are imperative, we propose Risk-driven Fault Injection (RDFI) techniques to address these challenges. RDFI applies the principles of chaos engineering to cloud security and leverages feedback loops to execute, monitor, analyze and plan security fault injection campaigns, based on a knowledge-base. The knowledge-base consists of fault models designed from secure baselines, cloud security best practices and observations derived during iterative fault injection campaigns. These observations are helpful for identifying vulnerabilities while verifying the correctness of security attributes (integrity, confidentiality and availability). Furthermore, RDFI proactively supports risk analysis and security hardening efforts by sharing security information with security mechanisms. We have designed and implemented the RDFI strategies including various chaos engineering algorithms as a software tool: CloudStrike. Several evaluations have been conducted with CloudStrike against infrastructure deployed on two major public cloud infrastructure: Amazon Web Services and Google Cloud Platform. The time performance linearly increases, proportional to increasing attack rates. Also, the analysis of vulnerabilities detected via security fault injection has been used to harden the security of cloud resources to demonstrate the effectiveness of the security information provided by CloudStrike. Therefore, we opine that our approaches are suitable for overcoming contemporary cloud security issues.
KW - cloud security
KW - security chaos engineering
KW - resilient architectures
KW - security risk assessment
Y1 - 2020
U6 - https://doi.org/10.1109/ACCESS.2020.3007338
SN - 2169-3536
VL - 8
SP - 123044
EP - 123060
PB - Institute of Electrical and Electronics Engineers
CY - Piscataway
ER -
TY - JOUR
A1 - Bin Tareaf, Raad
A1 - Berger, Philipp
A1 - Hennig, Patrick
A1 - Meinel, Christoph
T1 - Cross-platform personality exploration system for online social networks
BT - Facebook vs. Twitter
JF - Web intelligence
N2 - Social networking sites (SNS) are a rich source of latent information about individual characteristics. Crawling and analyzing this content provides a new approach for enterprises to personalize services and put forward product recommendations. In the past few years, commercial brands made a gradual appearance on social media platforms for advertisement, customers support and public relation purposes and by now it became a necessity throughout all branches. This online identity can be represented as a brand personality that reflects how a brand is perceived by its customers. We exploited recent research in text analysis and personality detection to build an automatic brand personality prediction model on top of the (Five-Factor Model) and (Linguistic Inquiry and Word Count) features extracted from publicly available benchmarks. Predictive evaluation on brands' accounts reveals that Facebook platform provides a slight advantage over Twitter platform in offering more self-disclosure for users' to express their emotions especially their demographic and psychological traits. Results also confirm the wider perspective that the same social media account carry a quite similar and comparable personality scores over different social media platforms. For evaluating our prediction results on actual brands' accounts, we crawled the Facebook API and Twitter API respectively for 100k posts from the most valuable brands' pages in the USA and we visualize exemplars of comparison results and present suggestions for future directions.
KW - Big Five model
KW - personality prediction
KW - brand personality
KW - machine
KW - learning
KW - social media analysis
Y1 - 2020
U6 - https://doi.org/10.3233/WEB-200427
SN - 2405-6456
SN - 2405-6464
VL - 18
IS - 1
SP - 35
EP - 51
PB - IOS Press
CY - Amsterdam
ER -
TY - JOUR
A1 - Kaitoua, Abdulrahman
A1 - Rabl, Tilmann
A1 - Markl, Volker
T1 - A distributed data exchange engine for polystores
JF - Information technology : methods and applications of informatics and information technology
JF - Information technology : Methoden und innovative Anwendungen der Informatik und Informationstechnik
N2 - There is an increasing interest in fusing data from heterogeneous sources. Combining data sources increases the utility of existing datasets, generating new information and creating services of higher quality. A central issue in working with heterogeneous sources is data migration: In order to share and process data in different engines, resource intensive and complex movements and transformations between computing engines, services, and stores are necessary.
Muses is a distributed, high-performance data migration engine that is able to interconnect distributed data stores by forwarding, transforming, repartitioning, or broadcasting data among distributed engines' instances in a resource-, cost-, and performance-adaptive manner. As such, it performs seamless information sharing across all participating resources in a standard, modular manner. We show an overall improvement of 30 % for pipelining jobs across multiple engines, even when we count the overhead of Muses in the execution time. This performance gain implies that Muses can be used to optimise large pipelines that leverage multiple engines.
KW - distributed systems
KW - data migration
KW - data transformation
KW - big data
KW - engine
KW - data integration
Y1 - 2020
U6 - https://doi.org/10.1515/itit-2019-0037
SN - 1611-2776
SN - 2196-7032
VL - 62
IS - 3-4
SP - 145
EP - 156
PB - De Gruyter
CY - Berlin
ER -
TY - JOUR
A1 - Dreseler, Markus
A1 - Boissier, Martin
A1 - Rabl, Tilmann
A1 - Uflacker, Matthias
T1 - Quantifying TPC-H choke points and their optimizations
JF - Proceedings of the VLDB Endowment
N2 - TPC-H continues to be the most widely used benchmark for relational OLAP systems. It poses a number of challenges, also known as "choke points", which database systems have to solve in order to achieve good benchmark results. Examples include joins across multiple tables, correlated subqueries, and correlations within the TPC-H data set. Knowing the impact of such optimizations helps in developing optimizers as well as in interpreting TPC-H results across database systems.
This paper provides a systematic analysis of choke points and their optimizations. It complements previous work on TPC-H choke points by providing a quantitative discussion of their relevance. It focuses on eleven choke points where the optimizations are beneficial independently of the database system. Of these, the flattening of subqueries and the placement of predicates have the biggest impact. Three queries (Q2, Q17, and Q21) are strongly ifluenced by the choice of an efficient query plan; three others (Q1, Q13, and Q18) are less influenced by plan optimizations and more dependent on an efficient execution engine.
Y1 - 2020
U6 - https://doi.org/10.14778/3389133.3389138
SN - 2150-8097
VL - 13
IS - 8
SP - 1206
EP - 1220
PB - Association for Computing Machinery
CY - New York
ER -
TY - CHAP
A1 - Abramova, Olga
T1 - Does a smile open all doors?
BT - understanding the impact of appearance disclosure on accommodation sharing platforms
T2 - Proceedings of the 53rd Hawaii International Conference on System Sciences
N2 - Online photographs govern an individual’s choices across a variety of contexts. In sharing arrangements, facial appearance has been shown to affect the desire to collaborate, interest to explore a listing, and even willingness to pay for a stay. Because of the ubiquity of online images and their influence on social attitudes, it seems crucial to be able to control these aspects. The present study examines the effect of different photographic self-disclosures on the provider’s perceptions and willingness to accept a potential co-sharer. The findings from our experiment in the accommodation-sharing context suggest social attraction mediates the effect of photographic self-disclosures on willingness to host. Implications of the results for IS research and practitioners are discussed.
KW - The Sharing Economy
KW - airbnb
KW - online photographs
KW - self-disclosure
KW - sharing economy
KW - social attraction
Y1 - 2020
SN - 978-0-9981331-3-3
SP - 831
EP - 840
PB - HICSS Conference Office University of Hawaii at Manoa
CY - Honolulu
ER -
TY - BOOK
A1 - Zhang, Shuhao
A1 - Plauth, Max
A1 - Eberhardt, Felix
A1 - Polze, Andreas
A1 - Lehmann, Jens
A1 - Sejdiu, Gezim
A1 - Jabeen, Hajira
A1 - Servadei, Lorenzo
A1 - Möstl, Christian
A1 - Bär, Florian
A1 - Netzeband, André
A1 - Schmidt, Rainer
A1 - Knigge, Marlene
A1 - Hecht, Sonja
A1 - Prifti, Loina
A1 - Krcmar, Helmut
A1 - Sapegin, Andrey
A1 - Jaeger, David
A1 - Cheng, Feng
A1 - Meinel, Christoph
A1 - Friedrich, Tobias
A1 - Rothenberger, Ralf
A1 - Sutton, Andrew M.
A1 - Sidorova, Julia A.
A1 - Lundberg, Lars
A1 - Rosander, Oliver
A1 - Sköld, Lars
A1 - Di Varano, Igor
A1 - van der Walt, Estée
A1 - Eloff, Jan H. P.
A1 - Fabian, Benjamin
A1 - Baumann, Annika
A1 - Ermakova, Tatiana
A1 - Kelkel, Stefan
A1 - Choudhary, Yash
A1 - Cooray, Thilini
A1 - Rodríguez, Jorge
A1 - Medina-Pérez, Miguel Angel
A1 - Trejo, Luis A.
A1 - Barrera-Animas, Ari Yair
A1 - Monroy-Borja, Raúl
A1 - López-Cuevas, Armando
A1 - Ramírez-Márquez, José Emmanuel
A1 - Grohmann, Maria
A1 - Niederleithinger, Ernst
A1 - Podapati, Sasidhar
A1 - Schmidt, Christopher
A1 - Huegle, Johannes
A1 - de Oliveira, Roberto C. L.
A1 - Soares, Fábio Mendes
A1 - van Hoorn, André
A1 - Neumer, Tamas
A1 - Willnecker, Felix
A1 - Wilhelm, Mathias
A1 - Kuster, Bernhard
ED - Meinel, Christoph
ED - Polze, Andreas
ED - Beins, Karsten
ED - Strotmann, Rolf
ED - Seibold, Ulrich
ED - Rödszus, Kurt
ED - Müller, Jürgen
T1 - HPI Future SOC Lab – Proceedings 2017
T1 - HPI Future SOC Lab – Proceedings 2017
N2 - The “HPI Future SOC Lab” is a cooperation of the Hasso Plattner Institute (HPI) and industry partners. Its mission is to enable and promote exchange and interaction between the research community and the industry partners.
The HPI Future SOC Lab provides researchers with free of charge access to a complete infrastructure of state of the art hard and software. This infrastructure includes components, which might be too expensive for an ordinary research environment, such as servers with up to 64 cores and 2 TB main memory. The offerings address researchers particularly from but not limited to the areas of computer science and business information systems. Main areas of research include cloud computing, parallelization, and In-Memory technologies.
This technical report presents results of research projects executed in 2017. Selected projects have presented their results on April 25th and November 15th 2017 at the Future SOC Lab Day events.
N2 - Das Future SOC Lab am HPI ist eine Kooperation des Hasso-Plattner-Instituts mit verschiedenen Industriepartnern. Seine Aufgabe ist die Ermöglichung und Förderung des Austausches zwischen Forschungsgemeinschaft und Industrie.
Am Lab wird interessierten Wissenschaftlern eine Infrastruktur von neuester Hard- und Software kostenfrei für Forschungszwecke zur Verfügung gestellt. Dazu zählen teilweise noch nicht am Markt verfügbare Technologien, die im normalen Hochschulbereich in der Regel nicht zu finanzieren wären, bspw. Server mit bis zu 64 Cores und 2 TB Hauptspeicher. Diese Angebote richten sich insbesondere an Wissenschaftler in den Gebieten Informatik und Wirtschaftsinformatik. Einige der Schwerpunkte sind Cloud Computing, Parallelisierung und In-Memory Technologien.
In diesem Technischen Bericht werden die Ergebnisse der Forschungsprojekte des Jahres 2017 vorgestellt. Ausgewählte Projekte stellten ihre Ergebnisse am 25. April und 15. November 2017 im Rahmen der Future SOC Lab Tag Veranstaltungen vor.
T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 130
KW - Future SOC Lab
KW - research projects
KW - multicore architectures
KW - In-Memory technology
KW - cloud computing
KW - machine learning
KW - artifical intelligence
KW - Future SOC Lab
KW - Forschungsprojekte
KW - Multicore Architekturen
KW - In-Memory Technologie
KW - Cloud Computing
KW - maschinelles Lernen
KW - Künstliche Intelligenz
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-433100
SN - 978-3-86956-475-3
SN - 1613-5652
SN - 2191-1665
IS - 130
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - CHAP
A1 - Dehnert, Maik
ED - Buchmann, Robert Andrei
ED - Polini, Andrea
ED - Johansson, Björn
ED - Karagiannis, Dimitris
T1 - Organizational change toward IT-supported personal advisory in incumbent banks
T2 - Perspectives in business informatics research
N2 - Due to changing customer behavior in digitalization, banks urge to change their traditional value creation in order to improve interaction with customers. New digital technologies such as core banking solutions change organizational structures to provide organizational and individual affordances in IT-supported personal advisory. Based on adaptive structuration theory and with qualitative data from 24 German banks, we identify first, second and third order issues of organizational change in value creation, which are connected with a set of affordances and constraints as the outcomes for customer interaction.
Y1 - 2020
SN - 978-3-030-61139-2
SN - 978-3-030-61140-8
U6 - https://doi.org/10.1007/978-3-030-61140-8_14
VL - 398
SP - 205
EP - 219
PB - Springer
CY - Cham
ER -