Institute for Information Technology

Germany

Institute for Information Technology

Germany

Time filter

Source Type

Ellen C.,Institute for Information Technology | Sieverding S.,Institute for Information Technology | Hungar H.,German Aerospace Center
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

The formal specification of functional requirements can often lead to inconsistency as well as unintended specification, especially in the early stages within the development process. In this paper, we present a formal model checking approach which tackles both of these problems and is also applicable during the requirements elicitation phase, in which no component model is available. The presented notion of consistency ensures the existence of at least one possible run of the system, which satisfies all requirements. To avoid trivial execution traces, the "intended" functional behavior of the requirements is triggered. The analysis is performed using model checking. More specifically, to reduce the overall analysis effort, we apply a bounded model checking scheme. If the set of requirements is inconsistent the method also identifies a maximal sub-set of consistent requirements. Alternatively, a minimal inconsistent sub-set can be computed. The approach is demonstrated on a railway crossing example using the BTC Embedded Specifier and the iSAT model checker. © 2014 Springer International Publishing.


Wortelen B.,Institute for Information Technology | Baumann M.,German Aerospace Center | Ludtke A.,Institute for Information Technology
Transportation Research Part F: Traffic Psychology and Behaviour | Year: 2013

The distribution of driver's attention is a crucial aspect for safe driving. The SEEV model by Wickens is a state of the art model that provides an easy but abstract way to estimate the distribution of attention for specific situations. The present paper presents an extension of the SEEV model, the Adaptive Information Expectancy (AIE) model. The AIE model is a sophisticated model of attention control, able to provide estimates based on a far more detailed simulation of human allocation of attention within a cognitive architecture. The AIE model relates attention directly to a task model, which is executed within the architecture. It is able to automatically measure task-dependent event frequencies and adapt its distribution of attention according to these frequencies. The AIE model was used to create a dynamic cognitive driver model. A driving simulator study with 21 participants has been conducted to evaluate the predictions of the driver model. Event rates for the primary driving task and an artificial secondary task have been varied, as well as the priorization of tasks. Both the SEEV and the AIE model provided estimates for percentage dwell times with similar quality, while the AIE model was able to provide estimates for further measure like gaze frequencies and link values. © 2013 Elsevier Ltd. All rights reserved.


Henze N.,University of Oldenburg | Poppinga B.,Institute for Information Technology | Boll S.,University of Oldenburg
NordiCHI 2010: Extending Boundaries - Proceedings of the 6th Nordic Conference on Human-Computer Interaction | Year: 2010

Since the introduction of application stores for mobile devices there has been an increasing interest to use this distribution platform to collect user feedback. Mobile application stores can make research prototypes widely available and enable to conduct user studies "in the wild" with participants from all over the world. Previous work published research prototypes to collect qualitative feedback or to collect quantitative attributes of specific prototypes. In this paper we explore how to conduct a study that focuses on a specific task and tries to isolate cause and effect much like controlled experiments in the lab. We compare three visualization techniques for off-screen objects by publishing a game in the Android Market. E.g. we show that the performance of the visualization techniques depends on the number of objects. Using a more realistic task and feedback from a hundred times more participants than previous studies lead to much higher external validity. We conclude that public experiments are a viable tool to complement or replace lab studies. © 2010 ACM.


Fortmann F.,Institute for Information Technology | Ludtke A.,Institute for Information Technology
IEEE International Conference on Industrial Informatics (INDIN) | Year: 2013

Building and maintaining Situation Awareness (SA) during supervisory control of a swarm of highly automated Unmanned Aerial Vehicles (UAV) is a complex and visually demanding process, which is often affected by weak scanning behaviors of the human operators. As a consequence severe errors, such as incorrect decisions, are likely to occur. This paper presents an Intelligent SA-Adaptive Interface (ISAAI) for supervisory control of a UAV swarm, which aims at optimizing the scanning behavior of a human operator with regard to his/her actual SA-needs. Therefore, the ISAAI integrates an eye movement based technique to assess human operator SA during mission execution and a technique for guiding visual attention to relevant but unattended information. © 2013 IEEE.


Blank M.,University of Oldenburg | Lehnhoff S.,Institute for Information Technology
IEEE International Conference on Industrial Informatics (INDIN) | Year: 2013

The energy system is due to substantial changes by reason of an ongoing decentralization of power supply. A challenge will be to provide ancillary services by distributed units since they are volatile regarding their power feed-in and hard to predict. This paper presents a method that allows for the evaluation of how reliable distributed units can participate in the provision of ancillary service products. This method can be used in order to assess unit coalitions with respect to their reliability. © 2013 IEEE.


Rabbath M.,Institute for Information Technology | Sandhaus P.,Institute for Information Technology | Boll S.,University of Oldenburg
WSM'10 - Proceedings of the 2nd ACM SIGMM Workshop on Social Media, Co-located with ACM Multimedia 2010 | Year: 2010

Photos are a special way to tell stories of our best memories. The representation of those photos in appealing physical photo books is highly appreciated by many people. Today, many photos are shared via social networking sites, where people upload their photos and share their stories with their friends. The members of the social network interact with the photo by commenting, adding tags or descriptions and uploading photos for the same events to their albums. While the media of different personal events are available on the social network, there is no easy way to collect and bundle them into a story and print this story as a photo book. We propose an approach to automatically detect media elements that match a query (where, when, what, who) in the user's social network and intelligently arrange and compose them into a printed photo book. We combine content analysis of text and images to automatically and semi-automatically select photos of a specific story. Photos that are highly probable to belong to the same event are clustered using an Expectation- Maximization algorithm to be able to easily retrieve them using online queries. People tags that are added to the photos are employed to select important photos by automatically calculating the individual social importance of friends. The selected content and derived semantics are employed to create an appealing layout for automatically created photo books.


Specht M.,Institute for Information Technology
Power Systems | Year: 2013

Smart Meters can be a major part of the future Smart Grid, as the are seen as a key technology to connect customers and enable the participation of the customer in the Smart Grid. Further a wide range of extended Smart Grid functionalities such as Demand and Response are supported. This chapter introduces the report of the Smart Meter Coordination Group to the European Smart Meter Mandate M/441. Furthermore, exemplary standards out of this report are described. In addition, several standards are presented, which are not included in the above mentioned report, but relevant to the standardization community. © Springer-Verlag Berlin Heidelberg 2013.


Lasche C.,Institute for Information Technology | Bode E.,Institute for Information Technology | Peikenkamp T.,Institute for Information Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

One of the effects of the radically changing energy market is that more and more offshore wind turbines are being constructed. To meet the increasing demand for renewable energy, many new companies with different levels of experience are entering the market. As the construction and maintenance of large offshore wind farms is a complex task, safety aspects of these operations are of crucial importance to avoid accidents. To this end, we introduce a method that assists in (1) identifying and precisely describing hazards of a scenario of an offshore operation, (2) quantifying their safety impact, and (3) developing risk mitigation means. Based on a guided hazard identification process, a formalization of hazardous scenarios will be proposed that unambiguously describes the risks of a given offshore operation. We will demonstrate the feasibility of our approach on a specific offshore scenario. © 2012 Springer-Verlag.


Niesse A.,Institute for Information Technology | Sonnenschein M.,University of Oldenburg
SMARTGREENS 2013 - Proceedings of the 2nd International Conference on Smart Grids and Green IT Systems | Year: 2013

Transforming the electric power system to incorporating a considerably increased share of renewable distributed generation implicates new challenges for the control of the system. To overcome the known shortcomings of centralized control, e.g. regarding scalability and robustness, a decentralized, self-organized system of agents for generators, loads and storages is widely discussed. We focus on a dynamic aggregation of these units to participate on current and future energy markets for both active power and new ancillary services products. With these units participating in system services, rescheduling of units within clusters becomes a more complex task that should reflect grid usage properties. In this work, we develop grid related cluster schedule resemblance as a metric to analyze the grid usage changes using graph theory. This metric can be used to compare different rescheduling options regarding grid usage for both dynamic clusters of distributed energy resources and for rescheduling of static clusters like virtual power plants. An example is used to show that this metric can be used as a separate optimization target for the multi-criteria optimization problem of cluster rescheduling.


Onken M.,Institute for Information Technology
Studies in Health Technology and Informatics | Year: 2012

Over the last years there has been a strong trend of publishing health data in anonymized format in order to make it available for research. This is also true for medical imaging where the DICOM standard is the predominant data format and network protocol. This paper proposes an extension to any DICOM networking infrastructure that permits sharing of medical images in an anonymized way. Standard DICOM software is utilized on client and server side. While offering researchers access to all images in anonymous format, the architecture enables authorized clinicians to access the same images including their original patient information (name, institution, etc.). Identifying parts and anonymous parts of the image data are stored to geologically different databases. Together with sophisticated network protocols, patient privacy is fully preserved. © 2012 European Federation for Medical Informatics and IOS Press. All rights reserved.

Loading Institute for Information Technology collaborators
Loading Institute for Information Technology collaborators