@article{AngerGebserJanhunenetal.2006, author = {Anger, Christian and Gebser, Martin and Janhunen, Tomi and Schaub, Torsten}, title = {What's a head without a body?}, year = {2006}, language = {en} } @article{Konczak2006, author = {Konczak, Kathrin}, title = {Weak order equivalence for Logic Programs with Prefernces}, year = {2006}, language = {en} } @article{Konczak2006, author = {Konczak, Kathrin}, title = {Voting Theory in Answer Set Programming}, year = {2006}, language = {en} } @article{SteuerHumburgSelbig2006, author = {Steuer, Ralf and Humburg, Peter and Selbig, Joachim}, title = {Validation and functional annotation of expression-based clusters based on gene ontology}, series = {BMC bioinformatics}, volume = {7}, journal = {BMC bioinformatics}, number = {380}, publisher = {BioMed Central}, address = {London}, issn = {1471-2105}, doi = {10.1186/1471-2105-7-380}, pages = {12}, year = {2006}, abstract = {Background: The biological interpretation of large-scale gene expression data is one of the paramount challenges in current bioinformatics. In particular, placing the results in the context of other available functional genomics data, such as existing bio-ontologies, has already provided substantial improvement for detecting and categorizing genes of interest. One common approach is to look for functional annotations that are significantly enriched within a group or cluster of genes, as compared to a reference group. Results: In this work, we suggest the information-theoretic concept of mutual information to investigate the relationship between groups of genes, as given by data-driven clustering, and their respective functional categories. Drawing upon related approaches (Gibbons and Roth, Genome Research 12: 1574-1581, 2002), we seek to quantify to what extent individual attributes are sufficient to characterize a given group or cluster of genes. Conclusion: We show that the mutual information provides a systematic framework to assess the relationship between groups or clusters of genes and their functional annotations in a quantitative way. Within this framework, the mutual information allows us to address and incorporate several important issues, such as the interdependence of functional annotations and combinatorial combinations of attributes. It thus supplements and extends the conventional search for overrepresented attributes within a group or cluster of genes. In particular taking combinations of attributes into account, the mutual information opens the way to uncover specific functional descriptions of a group of genes or clustering result. All datasets and functional annotations used in this study are publicly available. All scripts used in the analysis are provided as additional files.}, language = {en} } @article{ShenoyKrauledatBlankertzetal.2006, author = {Shenoy, Pradeep and Krauledat, Matthias and Blankertz, Benjamin and Rao, Rajesh P. N. and M{\"u}ller, Klaus-Robert}, title = {Towards adaptive classification for BCI}, doi = {10.1088/1741-2560/3/1/R02}, year = {2006}, abstract = {Non-stationarities are ubiquitous in EEG signals. They are especially apparent in the use of EEG-based brain- computer interfaces (BCIs): (a) in the differences between the initial calibration measurement and the online operation of a BCI, or (b) caused by changes in the subject's brain processes during an experiment (e.g. due to fatigue, change of task involvement, etc). In this paper, we quantify for the first time such systematic evidence of statistical differences in data recorded during offline and online sessions. Furthermore, we propose novel techniques of investigating and visualizing data distributions, which are particularly useful for the analysis of (non-) stationarities. Our study shows that the brain signals used for control can change substantially from the offline calibration sessions to online control, and also within a single session. In addition to this general characterization of the signals, we propose several adaptive classification schemes and study their performance on data recorded during online experiments. An encouraging result of our study is that surprisingly simple adaptive methods in combination with an offline feature selection scheme can significantly increase BCI performance}, language = {en} } @article{MeinelKlotz2006, author = {Meinel, Christoph and Klotz, Volker}, title = {The first 10 years of the ECCC digital library}, doi = {10.1145/1107458.1107484}, year = {2006}, language = {en} } @article{BlankertzDornhegeKrauledatetal.2006, author = {Blankertz, Benjamin and Dornhege, Guido and Krauledat, Matthias and M{\"u}ller, Klaus-Robert and Kunzmann, Volker and Losch, Florian and Curio, Gabriel}, title = {The Berlin brain-computer interface : EEG-based communication without subject training}, issn = {1534-4320}, doi = {10.1109/Tnsre.2006.875557}, year = {2006}, abstract = {The Berlin Brain-Computer Interface (BBCI) project develops a noninvasive BCI system whose key features are 1) the use of well-established motor competences as control paradigms, 2) high-dimensional features from 128-channel electroencephalogram (EEG), and 3) advanced machine learning techniques. As reported earlier, our experiments demonstrate that very high information transfer rates can be achieved using the readiness potential (RP) when predicting the laterality of upcoming left-versus right-hand movements in healthy subjects. A more recent study showed that the RP similarily accompanies phantom movements in arm amputees, but the signal strength decreases with longer loss of the limb. In a complementary approach, oscillatory features are used to discriminate imagined movements (left hand versus right hand versus foot). In a recent feedback study with six healthy subjects with no or very little experience with BCI control, three subjects achieved an information transfer rate above 35 bits per minute (bpm), and further two subjects above 24 and 15 bpm, while one subject could not achieve any BCI control. These results are encouraging for an EEG-based BCI system in untrained subjects that is independent of peripheral nervous system activity and does not rely on evoked potentials even when compared to results with very well-trained subjects operating other BCI systems}, language = {en} } @article{BlankertzMuellerKrusienskietal.2006, author = {Blankertz, Benjamin and M{\"u}ller, Klaus-Robert and Krusienski, Dean and Schalk, Gerwin and Wolpaw, Jonathan R. and Schl{\"o}gl, Alois and Pfurtscheller, Gert and Millan, Jos{\´e} del R. and Schr{\"o}der, Michael and Birbaumer, Niels}, title = {The BCI competition III : validating alternative approaches to actual BCI problems}, issn = {1534-4320}, doi = {10.1109/Tnsre.2006.875642}, year = {2006}, abstract = {A brain-computer interface (BCI) is a system that allows its users to control external devices with brain activity. Although the proof-of-concept was given decades ago, the reliable translation of user intent into device control commands is still a major challenge. Success requires the effective interaction of two adaptive controllers: the user's brain, which produces brain activity that encodes intent, and the BCI system, which translates that activity into device control commands. In order to facilitate this interaction, many laboratories are exploring a variety of signal analysis techniques to improve the adaptation of the BCI system to the user. In the literature, many machine learning and pattern classification algorithms have been reported to give impressive results when applied to BCI data in offline analyses. However, it is more difficult to evaluate their relative value for actual online use. BCI data competitions have been organized to provide objective formal evaluations of alternative methods. Prompted by the great interest in the first two BCI Competitions, we organized the third BCI Competition to address several of the most difficult and important analysis problems in BCI research. The paper describes the data sets that were provided to the competitors and gives an overview of the results.}, language = {en} } @phdthesis{Huang2006, author = {Huang, Wanjun}, title = {Temporary binding for dynamic middleware construction and web services composition}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-7672}, school = {Universit{\"a}t Potsdam}, year = {2006}, abstract = {With increasing number of applications in Internet and mobile environments, distributed software systems are demanded to be more powerful and flexible, especially in terms of dynamism and security. This dissertation describes my work concerning three aspects: dynamic reconfiguration of component software, security control on middleware applications, and web services dynamic composition. Firstly, I proposed a technology named Routing Based Workflow (RBW) to model the execution and management of collaborative components and realize temporary binding for component instances. The temporary binding means component instances are temporarily loaded into a created execution environment to execute their functions, and then are released to their repository after executions. The temporary binding allows to create an idle execution environment for all collaborative components, on which the change operations can be immediately carried out. The changes on execution environment will result in a new collaboration of all involved components, and also greatly simplifies the classical issues arising from dynamic changes, such as consistency preserving etc. To demonstrate the feasibility of RBW, I created a dynamic secure middleware system - the Smart Data Server Version 3.0 (SDS3). In SDS3, an open source implementation of CORBA is adopted and modified as the communication infrastructure, and three secure components managed by RBW, are created to enhance the security on the access of deployed applications. SDS3 offers multi-level security control on its applications from strategy control to application-specific detail control. For the management by RBW, the strategy control of SDS3 applications could be dynamically changed by reorganizing the collaboration of the three secure components. In addition, I created the Dynamic Services Composer (DSC) based on Apache open source projects, Apache Axis and WSIF. In DSC, RBW is employed to model the interaction and collaboration of web services and to enable the dynamic changes on the flow structure of web services. Finally, overall performance tests were made to evaluate the efficiency of the developed RBW and SDS3. The results demonstrated that temporary binding of component instances makes slight impacts on the execution efficiency of components, and the blackout time arising from dynamic changes can be extremely reduced in any applications.}, subject = {Middleware}, language = {en} } @article{GerbserSchaub2006, author = {Gerbser, Martin and Schaub, Torsten}, title = {Tableau calculi for answer set programming}, issn = {0302-9743}, doi = {10.1007/11799573}, year = {2006}, language = {en} } @book{Juergensen2006, author = {J{\"u}rgensen, Helmut}, title = {Synchronization}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, volume = {2006, 5}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, publisher = {Univ.}, address = {Potsdam}, issn = {0946-7580}, pages = {21 S.}, year = {2006}, language = {en} } @article{WilligMitschke2006, author = {Willig, Andreas and Mitschke, Robert}, title = {Results of bit error measurements with sensor nodes and casuistic consequences for design of energy-efficient error control schemes}, isbn = {978-3-540-32158-3}, year = {2006}, abstract = {For the proper design of energy-efficient error control schemes some insight into channel error patterns is needed. This paper presents bit error and packet loss measurements taken with sensor nodes running the popular RFM}, language = {en} } @phdthesis{Buchholz2006, author = {Buchholz, Henrik}, title = {Real-time visualization of 3D city models}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13337}, school = {Universit{\"a}t Potsdam}, year = {2006}, abstract = {An increasing number of applications requires user interfaces that facilitate the handling of large geodata sets. Using virtual 3D city models, complex geospatial information can be communicated visually in an intuitive way. Therefore, real-time visualization of virtual 3D city models represents a key functionality for interactive exploration, presentation, analysis, and manipulation of geospatial data. This thesis concentrates on the development and implementation of concepts and techniques for real-time city model visualization. It discusses rendering algorithms as well as complementary modeling concepts and interaction techniques. Particularly, the work introduces a new real-time rendering technique to handle city models of high complexity concerning texture size and number of textures. Such models are difficult to handle by current technology, primarily due to two problems: - Limited texture memory: The amount of simultaneously usable texture data is limited by the memory of the graphics hardware. - Limited number of textures: Using several thousand different textures simultaneously causes significant performance problems due to texture switch operations during rendering. The multiresolution texture atlases approach, introduced in this thesis, overcomes both problems. During rendering, it permanently maintains a small set of textures that are sufficient for the current view and the screen resolution available. The efficiency of multiresolution texture atlases is evaluated in performance tests. To summarize, the results demonstrate that the following goals have been achieved: - Real-time rendering becomes possible for 3D scenes whose amount of texture data exceeds the main memory capacity. - Overhead due to texture switches is kept permanently low, so that the number of different textures has no significant effect on the rendering frame rate. Furthermore, this thesis introduces two new approaches for real-time city model visualization that use textures as core visualization elements: - An approach for visualization of thematic information. - An approach for illustrative visualization of 3D city models. Both techniques demonstrate that multiresolution texture atlases provide a basic functionality for the development of new applications and systems in the domain of city model visualization.}, language = {en} } @misc{Lunemann2006, type = {Master Thesis}, author = {Lunemann, Carolin}, title = {Quantum cryptography : security analysis of multiuser quantum communication with embedded authentication}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12756}, school = {Universit{\"a}t Potsdam}, year = {2006}, abstract = {Three quantum cryptographic protocols of multiuser quantum networks with embedded authentication, allowing quantum key distribution or quantum direct communication, are discussed in this work. The security of the protocols against different types of attacks is analysed with a focus on various impersonation attacks and the man-in-the-middle attack. On the basis of the security analyses several improvements are suggested and implemented in order to adjust the investigated vulnerabilities. Furthermore, the impact of the eavesdropping test procedure on impersonation attacks is outlined. The framework of a general eavesdropping test is proposed to provide additional protection against security risks in impersonation attacks.}, language = {en} } @article{BordihnHolzer2006, author = {Bordihn, Henning and Holzer, Markus}, title = {Programmed grammars and their relation to the LBA problem}, series = {Acta informatica}, volume = {43}, journal = {Acta informatica}, publisher = {Elsevier}, address = {New York}, issn = {0001-5903}, doi = {10.1007/s00236-006-0017-9}, pages = {223 -- 242}, year = {2006}, abstract = {We consider generating and accepting programmed grammars with bounded degree of non-regulation, that is, the maximum number of elements in success or in failure fields of the underlying grammar. In particular, it is shown that this measure can be restricted to two without loss of descriptional capacity, regardless of whether arbitrary derivations or left-most derivations are considered. Moreover, in some cases, precise characterizations of the linear bounded automaton problem in terms of programmed grammars are obtained. Thus, the results presented in this paper shed new light on some longstanding open problem in the theory of computational complexity.}, language = {en} } @book{BalanJuergensen2006, author = {Balan, Sakthin M. and J{\"u}rgensen, Helmut}, title = {Peptide computing : universality and theoretical model}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, volume = {2006, 1}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, publisher = {Univ.}, address = {Potsdam}, issn = {0946-7580}, pages = {15 S.}, year = {2006}, language = {en} } @book{BalanJuergensen2006, author = {Balan, Sakthin M. and J{\"u}rgensen, Helmut}, title = {On the universality of peptide computing}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, volume = {2006, 9}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, publisher = {Univ.}, address = {Potsdam}, issn = {0946-7580}, pages = {ca. 23 S.}, year = {2006}, language = {en} } @article{LaubRothBuhmannetal.2006, author = {Laub, Julian and Roth, Volker and Buhmann, Joachim and M{\"u}ller, Klaus-Robert}, title = {On the information and representation of non-Euclidean pairwise data}, issn = {0031-3203}, doi = {10.1016/j.patcog.2006.04.016}, year = {2006}, abstract = {Two common data representations are mostly used in intelligent data analysis, namely the vectorial and the pairwise representation. Pairwise data which satisfy the restrictive conditions of Euclidean spaces can be faithfully translated into a Euclidean vectorial representation by embedding. Non-metric pairwise data with violations of symmetry, reflexivity or triangle inequality pose a substantial conceptual problem for pattern recognition since the amount of predictive structural information beyond what can be measured by embeddings is unclear. We show by systematic modeling of non-Euclidean pairwise data that there exists metric violations which can carry valuable problem specific information. Furthermore, Euclidean and non-metric data can be unified on the level of structural information contained in the data. Stable component analysis selects linear subspaces which are particularly insensitive to data fluctuations. Experimental results from different domains support our pattern recognition strategy.}, language = {en} } @article{GressmannJanhunenMerceretal.2006, author = {Gressmann, Jean and Janhunen, Tomi and Mercer, Robert E. and Schaub, Torsten and Thiele, Sven and Tichy, Richard}, title = {On probing and multi-threading in platypus}, year = {2006}, language = {en} } @article{GressmannJanhunenMerceretal.2006, author = {Gressmann, Jean and Janhunen, Tomi and Mercer, Robert E. and Schaub, Torsten and Thiele, Sven and Tichy, Richard}, title = {On probing and multi-threading in platypus}, year = {2006}, language = {en} }