TY  - GEN
A1  - Hullebus, Marc Antony
A1  - Tobin, Stephen J.
A1  - Gafos, Adamantios I.
T1  - Speaker-specific structure in German voiceless stop voice onset times
T2  - 19th Annual confernce of the international speech communication association (INTERSPEECH 2018), VOLS 1-6: speech research for emerging markets in multilingual societies
N2  - Voice onset time (VOT), a primary cue for voicing in many languages including English and German, is known to vary greatly between speakers, but also displays robust within-speaker consistencies, at least in English. The current analysis extends these findings to German. VOT measures were investigated from voiceless alveolar and velar stops in CV syllables cued by a visual prompt in a cue-distractor task. Comparably to English, a considerable portion of German VOT variability can be attributed to the syllable’s vowel length and the stop’s place of articulation. Individual differences in VOT still remain irrespective of speech rate. However, significant correlations across places of articulation and between speaker-specific mean VOTs and standard deviations indicate that talkers employ a relatively unified VOT profile across places of articulation. This could allow listeners to more efficiently adapt to speaker-specific realisations.
KW  - speech production
KW  - speech variability
KW  - voice onset time
Y1  - 2018
SN  - 978-1-5108-7221-9
U6  - https://doi.org/10.21437/Interspeech.2018-2288
SN  - 2308-457X
SP  - 1403
EP  - 1407
PB  - ISCA-International Speech Communication Association
CY  - Baixas
ER  - 
TY  - GEN
A1  - Sukmana, Muhammad Ihsan Haikal
A1  - Torkura, Kennedy A.
A1  - Cheng, Feng
A1  - Meinel, Christoph
A1  - Graupner, Hendrik
T1  - Unified logging system for monitoring multiple cloud storage providers in cloud storage broker
T2  - 32ND International Conference on Information Networking (ICOIN)
N2  - With the increasing demand for personal and enterprise data storage service, Cloud Storage Broker (CSB) provides cloud storage service using multiple Cloud Service Providers (CSPs) with guaranteed Quality of Service (QoS), such as data availability and security. However monitoring cloud storage usage in multiple CSPs has become a challenge for CSB due to lack of standardized logging format for cloud services that causes each CSP to implement its own format. In this paper we propose a unified logging system that can be used by CSB to monitor cloud storage usage across multiple CSPs. We gather cloud storage log files from three different CSPs and normalise these into our proposed log format that can be used for further analysis process. We show that our work enables a coherent view suitable for data navigation, monitoring, and analytics.
KW  - Unified logging system
KW  - Cloud Service Provider
KW  - cloud monitoring
KW  - data integration
KW  - security analytics
Y1  - 2018
SN  - 978-1-5386-2290-2
U6  - https://doi.org/10.1109/ICOIN.2018.8343081
SP  - 44
EP  - 49
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Torkura, Kennedy A.
A1  - Sukmana, Muhammad Ihsan Haikal
A1  - Strauss, Tim
A1  - Graupner, Hendrik
A1  - Cheng, Feng
A1  - Meinel, Christoph
T1  - CSBAuditor
BT  - proactive security risk analysis for cloud storage broker systems
T2  - 17th International Symposium on Network Computing and Applications (NCA)
N2  - Cloud Storage Brokers (CSB) provide seamless and concurrent access to multiple Cloud Storage Services (CSS) while abstracting cloud complexities from end-users. However, this multi-cloud strategy faces several security challenges including enlarged attack surfaces, malicious insider threats, security complexities due to integration of disparate components and API interoperability issues. Novel security approaches are imperative to tackle these security issues. Therefore, this paper proposes CSBAuditor, a novel cloud security system that continuously audits CSB resources, to detect malicious activities and unauthorized changes e.g. bucket policy misconfigurations, and remediates these anomalies. The cloud state is maintained via a continuous snapshotting mechanism thereby ensuring fault tolerance. We adopt the principles of chaos engineering by integrating Broker Monkey, a component that continuously injects failure into our reference CSB system, Cloud RAID. Hence, CSBAuditor is continuously tested for efficiency i.e. its ability to detect the changes injected by Broker Monkey. CSBAuditor employs security metrics for risk analysis by computing severity scores for detected vulnerabilities using the Common Configuration Scoring System, thereby overcoming the limitation of insufficient security metrics in existing cloud auditing schemes. CSBAuditor has been tested using various strategies including chaos engineering failure injection strategies. Our experimental evaluation validates the efficiency of our approach against the aforementioned security issues with a detection and recovery rate of over 96 %.
KW  - Cloud-Security
KW  - Cloud Audit
KW  - Security Metrics
KW  - Security Risk Assessment
KW  - Secure Configuration
Y1  - 2018
SN  - 978-1-5386-7659-2
U6  - https://doi.org/10.1109/NCA.2018.8548329
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Bin Tareaf, Raad
A1  - Berger, Philipp
A1  - Hennig, Patrick
A1  - Meinel, Christoph
T1  - ASEDS
BT  - Towards automatic social emotion detection system using facebook reactions
T2  - IEEE 20th International Conference on High Performance Computing and Communications; IEEE 16th International Conference on Smart City; IEEE 4th International Conference on Data Science and Systems (HPCC/SmartCity/DSS))
N2  - The Massive adoption of social media has provided new ways for individuals to express their opinion and emotion online. In 2016, Facebook introduced a new reactions feature that allows users to express their psychological emotions regarding published contents using so-called Facebook reactions. In this paper, a framework for predicting the distribution of Facebook post reactions is presented. For this purpose, we collected an enormous amount of Facebook posts associated with their reactions labels using the proposed scalable Facebook crawler. The training process utilizes 3 million labeled posts for more than 64,000 unique Facebook pages from diverse categories. The evaluation on standard benchmarks using the proposed features shows promising results compared to previous research. The final model is able to predict the reaction distribution on Facebook posts with a recall score of 0.90 for "Joy" emotion.
KW  - Emotion Mining
KW  - Psychological Emotions
KW  - Machine Learning
KW  - Social Media Analysis
KW  - Natural Language Processing
Y1  - 2018
SN  - 978-1-5386-6614-2
U6  - https://doi.org/10.1109/HPCC/SmartCity/DSS.2018.00143
SP  - 860
EP  - 866
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Lehmann, Frederike
A1  - Binet, Silvia
A1  - Franz, Alexandra
A1  - Taubert, Andreas
A1  - Schorr, Susan
T1  - Cation and anion substitutions in hybrid perovskites
BT  - solubility limits and phase stabilizing effects
T2  - 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC)
N2  - Organic or inorganic (A) metal (M) halide (X) perovskites (AMX(3)) are semiconductor materials setting the basis for the development of highly efficient, low-cost and multijunction solar energy conversion devices. The best efficiencies nowadays are obtained with mixed compositions containing methylammonium, formamidinium, Cs and Rb as well as iodine, bromine and chlorine as anions. The understanding of fundamental properties such as crystal structure and its effect on the band gap, as well as their phase stability is essential. In this systematic study X-ray diffraction and photoluminescense spectroscopy were applied to evaluate structural and optoelectronic properties of hybrid perovskites with mixed compositions.
Y1  - 2018
SN  - 978-1-5386-8529-7
U6  - https://doi.org/10.1109/PVSC.2018.8547645
SN  - 2159-2330
SN  - 2159-2349
SP  - 1555
EP  - 1558
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Teusner, Ralf
A1  - Matthies, Christoph
A1  - Staubitz, Thomas
T1  - What Stays in Mind?
BT  - Retention Rates in Programming MOOCs
T2  - IEEE Frontiers in Education Conference (FIE)
Y1  - 2018
SN  - 978-1-5386-1174-6
U6  - https://doi.org/10.1109/FIE.2018.8658890
SN  - 0190-5848
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Staubitz, Thomas
A1  - Meinel, Christoph
T1  - Collaborative Learning in MOOCs - Approaches and Experiments
T2  - 2018 IEEE Frontiers in Education (FIE) Conference
N2  - This Research-to-Practice paper examines the practical application of various forms of collaborative learning in MOOCs. Since 2012, about 60 MOOCs in the wider context of Information Technology and Computer Science have been conducted on our self-developed MOOC platform. The platform is also used by several customers, who either run their own platform instances or use our white label platform. We, as well as some of our partners, have experimented with different approaches in collaborative learning in these courses. Based on the results of early experiments, surveys amongst our participants, and requests by our business partners we have integrated several options to offer forms of collaborative learning to the system. The results of our experiments are directly fed back to the platform development, allowing to fine tune existing and to add new tools where necessary. In the paper at hand, we discuss the benefits and disadvantages of decisions in the design of a MOOC with regard to the various forms of collaborative learning. While the focus of the paper at hand is on forms of large group collaboration, two types of small group collaboration on our platforms are briefly introduced.
KW  - MOOC
KW  - Collaborative learning
KW  - Peer assessment
KW  - Team based assignment
KW  - Teamwork
Y1  - 2018
SN  - 978-1-5386-1174-6
SN  - 0190-5848
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Matthies, Christoph
A1  - Teusner, Ralf
A1  - Hesse, Günter
T1  - Beyond Surveys
BT  - Analyzing software development artifacts to assess teaching efforts
T2  - 2018 IEEE Frontiers in Education (FIE) Conference
KW  - software engineering
KW  - capstone course
KW  - development artifacts
KW  - Kanban
KW  - Scrum
KW  - Educational Data Mining
Y1  - 2018
SN  - 978-1-5386-1174-6
SN  - 978-1-5386-1175-3
SN  - 0190-5848
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Plauth, Max
A1  - Polze, Andreas
T1  - Towards improving data transfer efficiency for accelerators using hardware compression
T2  - Sixth International Symposium on Computing and Networking Workshops (CANDARW)
N2  - The overhead of moving data is the major limiting factor in todays hardware, especially in heterogeneous systems where data needs to be transferred frequently between host and accelerator memory. With the increasing availability of hardware-based compression facilities in modern computer architectures, this paper investigates the potential of hardware-accelerated I/O Link Compression as a promising approach to reduce data volumes and transfer time, thus improving the overall efficiency of accelerators in heterogeneous systems. Our considerations are focused on On-the-Fly compression in both Single-Node and Scale-Out deployments. Based on a theoretical analysis, this paper demonstrates the feasibility of hardware-accelerated On-the-Fly I/O Link Compression for many workloads in a Scale-Out scenario, and for some even in a Single-Node scenario. These findings are confirmed in a preliminary evaluation using software-and hardware-based implementations of the 842 compression algorithm.
KW  - Data compression
KW  - hardware
KW  - data transfer
KW  - accelerator architectures
Y1  - 2018
SN  - 978-1-5386-9184-7
U6  - https://doi.org/10.1109/CANDARW.2018.00031
SP  - 125
EP  - 131
PB  - IEEE
CY  - New York
ER  - 
TY  - GEN
A1  - Sprinz, Detlef F.
ED  - Luterbacher, Urs
ED  - Sprinz, Detlef F.
T1  - Our Conclusions
T2  - Global Climate Policy: Actors, Concepts, and Enduring Challenges
Y1  - 2018
SN  - 978-0-262-53534-2
SN  - 978-0-262-03792-1
SP  - 323
EP  - 335
PB  - MIT Press
CY  - Cambridge
ER  - 
TY  - GEN
A1  - Luterbacher, Urs
A1  - Sprinz, Detlef F.
ED  - Luterbacher, Urs
ED  - Sprinz, Detlef F.
T1  - Foreword
T2  - Global climate policy: actors, concepts, and enduring challenges
Y1  - 2018
SN  - 978-0-262-53534-2
SN  - 978-0-262-03792-1
SP  - IX
EP  - XI
PB  - MIT Press
CY  - Cambridge
ER  - 
TY  - GEN
A1  - Stojanovic, Vladeta
A1  - Trapp, Matthias
A1  - Richter, Rico
A1  - Döllner, Jürgen Roland Friedrich
T1  - A service-oriented approach for classifying 3D points clouds by example of office furniture classification
T2  - Web3D 2018: Proceedings of the 23rd International ACM Conference on 3D Web Technology
N2  - The rapid digitalization of the Facility Management (FM) sector has increased the demand for mobile, interactive analytics approaches concerning the operational state of a building. These approaches provide the key to increasing stakeholder engagement associated with Operation and Maintenance (O&M) procedures of living and working areas, buildings, and other built environment spaces. We present a generic and fast approach to process and analyze given 3D point clouds of typical indoor office spaces to create corresponding up-to-date approximations of classified segments and object-based 3D models that can be used to analyze, record and highlight changes of spatial configurations. The approach is based on machine-learning methods used to classify the scanned 3D point cloud data using 2D images. This approach can be used to primarily track changes of objects over time for comparison, allowing for routine classification, and presentation of results used for decision making. We specifically focus on classification, segmentation, and reconstruction of multiple different object types in a 3D point-cloud scene. We present our current research and describe the implementation of these technologies as a web-based application using a services-oriented methodology.
KW  - Indoor Models
KW  - 3D Point Clouds
KW  - Machine
KW  - Learning
KW  - BIM
KW  - Service-Oriented
Y1  - 2018
SN  - 978-1-4503-5800-2
U6  - https://doi.org/10.1145/3208806.3208810
SP  - 1
EP  - 9
PB  - Association for Computing Machinery
CY  - New York
ER  - 
TY  - GEN
A1  - Müller, Gesine
A1  - Locane, Jorge Joaquin
A1  - Loy, Benjamin
T1  - Introduction
T2  - Re-mapping World Literature: Writing, Book Markets and Epistemologies between Latin America and the Global South / Escrituras, mercados y epistemologías entre América Latina y el Sur Global
Y1  - 2018
SN  - 978-3-11-054957-7
SN  - 978-3-11-054952-2
U6  - https://doi.org/10.1515/9783110549577-001
SN  - 2513-0757
SP  - 1
EP  - 12
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - GEN
A1  - Bartz, Christian
A1  - Yang, Haojin
A1  - Meinel, Christoph
T1  - SEE: Towards semi-supervised end-to-end scene text recognition
T2  - Proceedings of the Thirty-Second AAAI Conference on Artificial Intelligence, Thirtieth Innovative Applications of Artificial Intelligence Conference, Eight Symposium on Educational Advances in Artificial Intelligence
N2  - Detecting and recognizing text in natural scene images is a challenging, yet not completely solved task. In recent years several new systems that try to solve at least one of the two sub-tasks (text detection and text recognition) have been proposed. In this paper we present SEE, a step towards semi-supervised neural networks for scene text detection and recognition, that can be optimized end-to-end. Most existing works consist of multiple deep neural networks and several pre-processing steps. In contrast to this, we propose to use a single deep neural network, that learns to detect and recognize text from natural images, in a semi-supervised way. SEE is a network that integrates and jointly learns a spatial transformer network, which can learn to detect text regions in an image, and a text recognition network that takes the identified text regions and recognizes their textual content. We introduce the idea behind our novel approach and show its feasibility, by performing a range of experiments on standard benchmark datasets, where we achieve competitive results.
Y1  - 2018
SN  - 978-1-57735-800-8
VL  - 10
SP  - 6674
EP  - 6681
PB  - ASSOC Association for the Advancement of Artificial Intelligence
CY  - Palo Alto
ER  - 
TY  - GEN
A1  - Bosser, Anne-Gwenn
A1  - Cabalar, Pedro
A1  - Dieguez, Martin
A1  - Schaub, Torsten
T1  - Introducing temporal stable models for linear dynamic logic
T2  - 16th International Conference on Principles of Knowledge Representation and Reasoning
N2  - We propose a new temporal extension of the logic of Here-and-There (HT) and its equilibria obtained by combining it with dynamic logic over (linear) traces. Unlike previous temporal extensions of HT based on linear temporal logic, the dynamic logic features allow us to reason about the composition of actions. For instance, this can be used to exercise fine grained control when planning in robotics, as exemplified by GOLOG. In this paper, we lay the foundations of our approach, and refer to it as Linear Dynamic Equilibrium Logic, or simply DEL. We start by developing the formal framework of DEL and provide relevant characteristic results. Among them, we elaborate upon the relationships to traditional linear dynamic logic and previous temporal extensions of HT.
Y1  - 2018
UR  - https://www.dc.fi.udc.es/~cabalar/del.pdf
SP  - 12
EP  - 21
PB  - ASSOC Association for the Advancement of Artificial Intelligence
CY  - Palo Alto
ER  - 
TY  - GEN
A1  - Discher, Sören
A1  - Richter, Rico
A1  - Döllner, Jürgen Roland Friedrich
ED  - Spencer, SN
T1  - A scalable webGL-based approach for visualizing massive 3D point clouds using semantics-dependent rendering techniques
T2  - Web3D 2018: The 23rd International ACM Conference on 3D Web Technology
N2  - 3D point cloud technology facilitates the automated and highly detailed digital acquisition of real-world environments such as assets, sites, cities, and countries; the acquired 3D point clouds represent an essential category of geodata used in a variety of geoinformation applications and systems. In this paper, we present a web-based system for the interactive and collaborative exploration and inspection of arbitrary large 3D point clouds. Our approach is based on standard WebGL on the client side and is able to render 3D point clouds with billions of points. It uses spatial data structures and level-of-detail representations to manage the 3D point cloud data and to deploy out-of-core and web-based rendering concepts. By providing functionality for both, thin-client and thick-client applications, the system scales for client devices that are vastly different in computing capabilities. Different 3D point-based rendering techniques and post-processing effects are provided to enable task-specific and data-specific filtering and highlighting, e.g., based on per-point surface categories or temporal information. A set of interaction techniques allows users to collaboratively work with the data, e.g., by measuring distances and areas, by annotating, or by selecting and extracting data subsets. Additional value is provided by the system's ability to display additional, context-providing geodata alongside 3D point clouds and to integrate task-specific processing and analysis operations. We have evaluated the presented techniques and the prototype system with different data sets from aerial, mobile, and terrestrial acquisition campaigns with up to 120 billion points to show their practicality and feasibility.
KW  - 3D Point Clouds
KW  - web-based rendering
KW  - point-based rendering
Y1  - 2018
SN  - 978-1-4503-5800-2
U6  - https://doi.org/10.1145/3208806.3208816
SP  - 1
EP  - 9
PB  - Association for Computing Machinery
CY  - New York
ER  - 
TY  - GEN
A1  - Combi, Carlo
A1  - Oliboni, Barbara
A1  - Weske, Mathias
A1  - Zerbato, Francesca
ED  - Trujillo, JC Davis
T1  - Conceptual modeling of processes and data
BT  - Connecting different perspectives
T2  - Conceptual Modeling, ER 2018
N2  - Business processes constantly generate, manipulate, and consume data that are managed by organizational databases. Despite being central to process modeling and execution, the link between processes and data is often handled by developers when the process is implemented, thus leaving the connection unexplored during the conceptual design. In this paper, we introduce, formalize, and evaluate a novel conceptual view that bridges the gap between process and data models, and show some kinds of interesting insights that can be derived from this novel proposal.
Y1  - 2018
SN  - 978-3-030-00847-5
SN  - 978-3-030-00846-8
U6  - https://doi.org/10.1007/978-3-030-00847-5_18
SN  - 0302-9743
SN  - 1611-3349
VL  - 11157
SP  - 236
EP  - 250
PB  - Springer
CY  - Cham
ER  - 
TY  - GEN
A1  - Frank, Mario
A1  - Kreitz, Christoph
T1  - A theorem prover for scientific and educational purposes
T2  - Electronic proceedings in theoretical computer science
N2  - We present a prototype of an integrated reasoning environment for educational purposes. The presented tool is a fragment of a proof assistant and automated theorem prover. We describe the existing and planned functionality of the theorem prover and especially the functionality of the educational fragment. This currently supports working with terms of the untyped lambda calculus and addresses both undergraduate students and researchers. We show how the tool can be used to support the students' understanding of functional programming and discuss general problems related to the process of building theorem proving software that aims at supporting both research and education.
Y1  - 2018
U6  - https://doi.org/10.4204/EPTCS.267.4
SN  - 2075-2180
IS  - 267
SP  - 59
EP  - 69
PB  - Open Publishing Association
CY  - Sydney
ER  - 
TY  - GEN
A1  - Alviano, Mario
A1  - Romero Davila, Javier
A1  - Schaub, Torsten
T1  - Preference Relations by Approximation
T2  - Sixteenth International Conference on Principles of Knowledge Representation and Reasoning
N2  - Declarative languages for knowledge representation and reasoning provide constructs to define preference relations over the set of possible interpretations, so that preferred models represent optimal solutions of the encoded problem. We introduce the notion of approximation for replacing preference relations with stronger preference relations, that is, relations comparing more pairs of interpretations. Our aim is to accelerate the computation of a non-empty subset of the optimal solutions by means of highly specialized algorithms. We implement our approach in Answer Set Programming (ASP), where problems involving quantitative and qualitative preference relations can be addressed by ASPRIN, implementing a generic optimization algorithm. Unlike this, chains of approximations allow us to reduce several preference relations to the preference relations associated with ASP’s native weak constraints and heuristic directives. In this way, ASPRIN can now take advantage of several highly optimized algorithms implemented by ASP solvers for computing optimal solutions
Y1  - 2018
SP  - 2
EP  - 11
PB  - AAAI Conference on Artificial Intelligence
CY  - Palo Alto
ER  - 
TY  - GEN
A1  - Schäpers, Björn
A1  - Niemueller, Tim
A1  - Lakemeyer, Gerhard
A1  - Gebser, Martin
A1  - Schaub, Torsten
T1  - ASP-Based Time-Bounded Planning for Logistics Robots
T2  - Twenty-Eighth International Conference on Automated Planning and Scheduling (ICAPS 2018)
N2  - Manufacturing industries are undergoing a major paradigm shift towards more autonomy. Automated planning and scheduling then becomes a necessity. The Planning and Execution Competition for Logistics Robots in Simulation held at ICAPS is based on this scenario and provides an interesting testbed. However, the posed problem is challenging as also demonstrated by the somewhat weak results in 2017. The domain requires temporal reasoning and dealing with uncertainty. We propose a novel planning system based on Answer Set Programming and the Clingo solver to tackle these problems and incentivize robot cooperation. Our results show a significant performance improvement, both, in terms of lowering computational requirements and better game metrics.
Y1  - 2018
SN  - 2334-0835
SN  - 2334-0843
SP  - 509
EP  - 517
PB  - ASSOC Association for the Advancement of Artificial Intelligence
CY  - Palo Alto
ER  -