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91.
Idilio Drago Rafael R. R. Barbosa Ramin Sadre Aiko Pras Jürgen Schönwälder 《Journal of Network and Systems Management》2011,19(2):298-304
Following the success of the First Workshop on the Usage of NetFlow/IPFIX (Pras et al. in J Netw Syst Manag 17(4), 2009) in 2008, the European EMANICS Network of Excellence organized a second workshop
in October 2009, held at Jacobs University Bremen. This report summarizes the workshop and presents its main conclusions. 相似文献
92.
Waser J Ribičić H Fuchs R Hirsch C Schindler B Blöschl G Gröller ME 《IEEE transactions on visualization and computer graphics》2011,17(12):1872-1881
Flood disasters are the most common natural risk and tremendous efforts are spent to improve their simulation and management. However, simulation-based investigation of actions that can be taken in case of flood emergencies is rarely done. This is in part due to the lack of a comprehensive framework which integrates and facilitates these efforts. In this paper, we tackle several problems which are related to steering a flood simulation. One issue is related to uncertainty. We need to account for uncertain knowledge about the environment, such as levee-breach locations. Furthermore, the steering process has to reveal how these uncertainties in the boundary conditions affect the confidence in the simulation outcome. Another important problem is that the simulation setup is often hidden in a black-box. We expose system internals and show that simulation steering can be comprehensible at the same time. This is important because the domain expert needs to be able to modify the simulation setup in order to include local knowledge and experience. In the proposed solution, users steer parameter studies through the World Lines interface to account for input uncertainties. The transport of steering information to the underlying data-flow components is handled by a novel meta-flow. The meta-flow is an extension to a standard data-flow network, comprising additional nodes and ropes to abstract parameter control. The meta-flow has a visual representation to inform the user about which control operations happen. Finally, we present the idea to use the data-flow diagram itself for visualizing steering information and simulation results. We discuss a case-study in collaboration with a domain expert who proposes different actions to protect a virtual city from imminent flooding. The key to choosing the best response strategy is the ability to compare different regions of the parameter space while retaining an understanding of what is happening inside the data-flow system. 相似文献
93.
Jürgen Abel 《Software》2010,40(9):751-777
The lossless Burrows–Wheeler compression algorithm has received considerable attention over recent years for both its simplicity and effectiveness. It is based on a permutation of the input sequence—the Burrows–Wheeler transformation (BWT)—which groups symbols with a similar context close together. In the original version, this permutation was followed by a Move‐To‐Front transformation and a final entropy coding stage. Later versions used different algorithms, placed after the BWT, since the following stages have a significant influence on the compression rate. This paper describes different algorithms and improvements for these post BWT stages including a new context‐based approach. The results for compression rates are presented together with compression and decompression times on the Calgary corpus, the Canterbury corpus, the large Canterbury corpus and the Lukas 2D 16‐bit medical image corpus. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
94.
95.
Three training methods to improve attention management skills in process control were compared. Forty students from technical disciplines participated in a five-hour module of emphasis shift training (EST), EST combined with situation awareness training (EST/SA), and drill and practice (D&P) on a simulated process control task. Participants were then tested three times for 45 min each (immediately after training, two weeks after training, and six weeks after training) for system control performance and diagnostic performance on familiar and nonfamiliar fault states. D&P led to superior diagnostic performance on familiar system faults. EST/SA training supported the diagnosis of novel system faults. EST was less effective than expected for system control performance. Implications for training design in process control are discussed. 相似文献
96.
Tristan Behrens Mehdi Dastani Jürgen Dix Michael Köster Peter Novák 《Annals of Mathematics and Artificial Intelligence》2010,59(3-4):277-311
The Multi-Agent Programming Contest is an annual international event on programming multi-agent systems: Teams of agents participate in a simulated cooperative scenario. It started in 2005 and is organised in 2010 for the sixth time. The contest is an attempt to stimulate research in the area of multi-agent system development and programming by (i) identifying key problems in the field and (ii) collecting suitable benchmarks that can serve as milestones for testing multi-agent programming languages, platforms and tools. This article provides a short history of the contest since it started and reports in more detail on the cows and cowboys scenario implemented for the 2008, 2009 and 2010 contest editions. We briefly discuss the underlying technological background and conclude with a critical discussion of the experiences and lessons learned. 相似文献
97.
Waser J Fuchs R Ribicić H Schindler B Blöschl G Gröller E 《IEEE transactions on visualization and computer graphics》2010,16(6):1458-1467
In this paper we present World Lines as a novel interactive visualization that provides complete control over multiple heterogeneous simulation runs. In many application areas, decisions can only be made by exploring alternative scenarios. The goal of the suggested approach is to support users in this decision making process. In this setting, the data domain is extended to a set of alternative worlds where only one outcome will actually happen. World Lines integrate simulation, visualization and computational steering into a single unified system that is capable of dealing with the extended solution space. World Lines represent simulation runs as causally connected tracks that share a common time axis. This setup enables users to interfere and add new information quickly. A World Line is introduced as a visual combination of user events and their effects in order to present a possible future. To quickly find the most attractive outcome, we suggest World Lines as the governing component in a system of multiple linked views and a simulation component. World Lines employ linking and brushing to enable comparative visual analysis of multiple simulations in linked views. Analysis results can be mapped to various visual variables that World Lines provide in order to highlight the most compelling solutions. To demonstrate this technique we present a flooding scenario and show the usefulness of the integrated approach to support informed decision making. 相似文献
98.
In last years, Face recognition based on 3D techniques is an emergent technology which has demonstrated better results than
conventional 2D approaches. Using texture (180° multi-view image) and depth maps is supposed to increase the robustness towards
the two main challenges in Face Recognition: Pose and illumination. Nevertheless, 3D data should be acquired under highly
controlled conditions and in most cases depends on the collaboration of the subject to be recognized. Thus, in applications
such as surveillance or control access points, this kind of 3D data may not be available during the recognition process. This
leads to a new paradigm using some mixed 2D-3D face recognition systems where 3D data is used in the training but either 2D
or 3D information can be used in the recognition depending on the scenario. Following this concept, where only part of the
information (partial concept) is used in the recognition, a novel method is presented in this work. This has been called Partial
Principal Component Analysis (P2CA) since they fuse the Partial concept with the fundamentals of the well known PCA algorithm. This strategy has been proven
to be very robust in pose variation scenarios showing that the 3D training process retains all the spatial information of
the face while the 2D picture effectively recovers the face information from the available data. Furthermore, in this work,
a novel approach for the automatic creation of 180° aligned cylindrical projected face images using nine different views is
presented. These face images are created by using a cylindrical approximation for the real object surface. The alignment is
done by applying first a global 2D affine transformation of the image, and afterward a local transformation of the desired
face features using a triangle mesh. This local alignment allows a closer look to the feature properties and not the differences.
Finally, these aligned face images are used for training a pose invariant face recognition approach (P2CA). 相似文献
99.
Jürgen Bernard Jan Brase Dieter Fellner Oliver Koepler Jörn Kohlhammer Tobias Ruppert Tobias Schreck Irina Sens 《International Journal on Digital Libraries》2010,11(2):111-123
Digital Library support for textual and certain types of non-textual documents has significantly advanced over the last years.
While Digital Library support implies many aspects along the whole library workflow model, interactive and visual retrieval
allowing effective query formulation and result presentation are important functions. Recently, new kinds of non-textual documents
which merit Digital Library support, but yet cannot be fully accommodated by existing Digital Library technology, have come
into focus. Scientific data, as produced for example, by scientific experimentation, simulation or observation, is such a
document type. In this article we report on a concept and first implementation of Digital Library functionality for supporting
visual retrieval and exploration in a specific important class of scientific primary data, namely, time-oriented research
data. The approach is developed in an interdisciplinary effort by experts from the library, natural sciences, and visual analytics
communities. In addition to presenting the concept and to discussing relevant challenges, we present results from a first
implementation of our approach as applied on a real-world scientific primary data set. We also report from initial user feedback
obtained during discussions with domain experts from the earth observation sciences, indicating the usefulness of our approach. 相似文献
100.
Jürgen Taeger 《Datenschutz und Datensicherheit - DuD》2010,34(4):246-249
Das Bundesdatenschutzgesetz (BDSG) und das Telemediengesetz (TMG) verpflichten datenerhebende und -verarbeitende Stellen,
bei Betroffenen Transparenz über die Verarbeitung ihrer Daten herzustellen. Nach § 13 Abs. 1 TMG hat der Anbieter über die
Verarbeitung von Daten bei der Nutzung eines Teledienstes zu informieren. Nutzt der Betroffene ein internetf?higes Handy als
mobiles Endger?t, ist das Darstellungsvolumen auf kleinen Displays allerdings beschr?nkt. Anbieter müssen sich bei der Umsetzung
der bu?geldbewehrten Informationspflicht darauf einstellen. 相似文献