@inbook{19836, author = {{Schindelhauer, Christian and Voß, Kerstin}}, booktitle = {{Proc. of 4th International Conference on Ad-Hoc Networks & Wireless (ADHOC-NOW 2005)}}, isbn = {{9783540291329}}, issn = {{0302-9743}}, pages = {{271--284}}, title = {{{Probability Distributions for Channel Utilisation}}}, doi = {{10.1007/11561354_23}}, year = {{2005}}, } @inproceedings{19837, author = {{Schindelhauer, Christian and Weikum, Gerhard and Hales, David and Triantafillou, Peter}}, booktitle = {{European Conference on Complex Systems (ECCS 2005)}}, title = {{{Towards Self-Organizing Query Routing and Processing for Peer-to-Peer Web Search}}}, year = {{2005}}, } @inproceedings{19871, abstract = {{Data has become the most valuable asset for many companies; loosing important data can cause companies to fail quite immediately. The protection of data inside storage systems is mostly achieved by using a RAID scheme that adds redundant data to user data, enabling recovery from single or multiple disk failures. This protection against data loss in case of a disk failure can be achieved either by dedicated hardware or a software RAID solution.

One major advantage of software RAID is that it comes for free as a built-in functionality in many operating systems like Linux or Microsoft Windows. The drawback of the built-in functionality is that it is not suited to run in multiple server environments; synchronization and recovery processes can be corrupted if more than a single server is allowed to access a software RAID volume.

In this paper, we present an enhancement for the Linux md-driver that enables a consistent usage of RAID in multiple server environments. Based on the V:DRIVE virtualization environment, RAID volumes can be consistently synchronized and recovered even in distributed environments. Besides the architectural concepts, we present measurements that indicate the viability of this enhanced, distributed version of md.}}, author = {{Brinkmann, André and Effert, Sascha and Heidebuer, Michael and Vodisek, Mario}}, booktitle = {{In Proceedings of the International Workshop on Storage Network Architecture and Parallel I/Os}}, pages = {{81 -- 88}}, title = {{{Distributed MD}}}, year = {{2005}}, } @inproceedings{19872, abstract = {{Recent developments both in the business and the technological domain have led to a significant increase in demand for Business Intelligence (BI) infrastructures that can handle huge amounts of data in small time frames. BI applications are increasingly used by large user bases on all management levels; support tasks spanning the complete value chain are based on transactional data and are directly coupled with operational systems in ”closed loop” approaches.

To effectively handle the resulting data volume turns out to be an extremely challenging task which encompasses a variety of issues on different levels. We propose an integrated multi layer tool for monitoring, benchmarking, analyzing, and optimizing the performance of such BI infrastructures.

Inside this paper we give a coarse outline of the tool’s architecture and demonstrate the value of distinct measurement points at operating system layer. For that purpose we introduce a kernel based benchmark environment and present first measurement results. The gathered data clearly indicates that a meaningful analysis of performance benchmarks without kernel trace points is of limited value - which shows the necessity to consider a separate component within the tool’s architecture.}}, author = {{Brinkmann, André and Effert, Sascha and Heidebuer, Michael and Vodisek, Mario and Baars, Henning}}, booktitle = {{In Proceedings of the International Workshop on Storage Network Architecture and Parallel I/Os}}, pages = {{1--8}}, title = {{{An integrated Architecture for Business Intelligence support from Application down to Storage}}}, year = {{2005}}, } @inproceedings{19888, author = {{Klein, Jan and Zachmann, Gabriel}}, booktitle = {{ACM SIGGRAPH 2005 Posters on - SIGGRAPH '05}}, title = {{{The expected running time of hierarchical collision detection}}}, doi = {{10.1145/1186954.1187087}}, year = {{2005}}, } @inproceedings{19890, author = {{Klein, Jan and Zachmann, Gabriel}}, booktitle = {{Proceedings of the 13-th International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision'2005 (WSCG'2005)}}, pages = {{163--170}}, title = {{{Interpolation Search for Point Cloud Intersection}}}, doi = {{10.1145/1186223.1186329}}, year = {{2005}}, } @inproceedings{19912, author = {{Loeser, Chris and Schomaker, Gunnar and Brinkmann, André and Vodisek, Mario and Heidebuer, Michael}}, booktitle = {{Proceedings of the 4th International Conference on Networking}}, isbn = {{9783540253389}}, issn = {{0302-9743}}, pages = {{800--810}}, title = {{{Content Distribution in Heterogenous Video-on-Demand P2P Networks with ARIMA Forecasts}}}, doi = {{10.1007/978-3-540-31957-3_90}}, volume = {{3421}}, year = {{2005}}, } @article{26278, author = {{Ziegler, Martin and Fuchssteiner, Benno}}, issn = {{0020-7748}}, journal = {{International Journal of Theoretical Physics}}, pages = {{693--717}}, title = {{{Nonlinear Reformulation of Heisenberg's Dynamics}}}, doi = {{10.1007/s10773-005-7048-9}}, year = {{2005}}, } @inproceedings{28987, author = {{Schindelhauer, Christian and Schomaker, Gunnar}}, booktitle = {{SPAA 2005: Proceedings of the 17th Annual ACM Symposium on Parallelism in Algorithms and Architectures, Las Vegas, Nevada, USA}}, title = {{{Weighted distributed hash tables}}}, doi = {{10.1145/1073970.1074008}}, year = {{2005}}, } @inbook{26991, author = {{Rührup, Stefan and Schindelhauer, Christian}}, booktitle = {{Algorithms – ESA 2005}}, issn = {{0302-9743}}, title = {{{Online Routing in Faulty Meshes with Sub-linear Comparative Time and Traffic Ratio}}}, doi = {{10.1007/11561071_5}}, year = {{2005}}, } @phdthesis{17413, author = {{Fischer, Matthias}}, isbn = {{3-935433-73-5}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{Design, analysis, and evaluation of a data structure for distributed virtual environments}}}, volume = {{164}}, year = {{2005}}, } @article{17414, abstract = {{Nowadays companies operate in a difficult environment: the dynamics of innovations increase and product life cycles become shorter. Furthermore products and the corresponding manufacturing processes get more and more complex. Therefore, companies need new methods for the planning of manufacturing systems. One promising approach in this context is digital factory/virtual production—the modeling and analysis of computer models of the planned factory with the objective to reduce time and costs. For the modeling and analysis various simulation methods and programs have been developed. They are a highly valuable support for planning and visualizing the manufacturing system. But there is one major disadvantage: only experienced and long trained experts are able to operate with these programs. The graphical user interface is very complex and not intuitive to use. This results in an extensive and error-prone modeling of complex simulation models and a time-consuming interpretation of the simulation results. To overcome these weak points, intuitive and understandable man–machine interfaces like augmented and virtual reality can be used. This paper describes the architecture of a system which uses the technologies of augmented and virtual reality to support the planning process of complex manufacturing systems. The proposed system assists the user in modeling, the validation of the simulation model, and the subsequent optimization of the production system. A general application of the VR- and AR-technologies and of the simulation is realized by the development of appropriate linking and integration mechanisms. For the visualization of the arising 3D-data within the VR- and AR-environments, a dedicated 3D-rendering library is used.}}, author = {{Dangelmaier, Wilhelm and Fischer, Matthias and Gausemeier, Jürgen and Grafe, Michael and Matysczok, Carsten and Mueck, Bengt}}, issn = {{0166-3615}}, journal = {{Computers in Industry}}, pages = {{371--383}}, title = {{{Virtual and augmented reality support for discrete manufacturing system simulation}}}, doi = {{10.1016/j.compind.2005.01.007}}, year = {{2005}}, } @inproceedings{17415, author = {{Fischer, Matthias and Mueck, B. and Mahajan, K. and Kortenjan, M. and Laroque, C. and Dangelmaier, W.}}, booktitle = {{Proceedings of the Winter Simulation Conference}}, isbn = {{0780395190}}, title = {{{Multi-User Support and Motion Planning of Humans and Humans Driven Vehicles in Interactive 3D Material Flow Simulations}}}, doi = {{10.1109/wsc.2005.1574470}}, year = {{2005}}, } @article{18763, abstract = {{Property testing is a relaxation of classical decision problems which aims at distinguishing between functions having a predetermined property and functions being far from any function having the property. In this paper we present a novel framework for analyzing property testing algorithms. Our framework is based on a connection of property testing and a new class of problems which we call abstract combinatorial programs . We show that if the problem of testing a property can be reduced to an abstract combinatorial program of small dimension , then the property has an efficient tester. We apply our framework to a variety of problems. We present efficient property testing algorithms for geometric clustering problems, for the reversal distance problem, and for graph and hypergraph coloring problems. We also prove that, informally, any hereditary graph property can be efficiently tested if and only if it can be reduced to an abstract combinatorial program of small size. Our framework allows us to analyze all our testers in a unified way, and the obtained complexity bounds either match or improve the previously known bounds. Furthermore, even if the asymptotic complexity of the testers is not improved, the obtained proofs are significantly simpler than the previous ones. We believe that our framework will help to understand the structure of efficiently testable properties.}}, author = {{Czumaj, Artur and Sohler, Christian}}, issn = {{0097-5397}}, journal = {{SIAM Journal on Computing}}, number = {{3}}, pages = {{580--615}}, title = {{{Abstract Combinatorial Programs and Efficient Property Testers}}}, doi = {{10.1137/s009753970444199x}}, volume = {{34}}, year = {{2005}}, } @inproceedings{18768, author = {{Bădoiu, Mihai and Czumaj, Artur and Indyk, Piotr and Sohler, Christian}}, booktitle = {{Proc. of the 32nd International Colloquium on Automata, Languages and Programming (ICALP)}}, isbn = {{9783540275800}}, issn = {{0302-9743}}, pages = {{866--877}}, title = {{{Facility Location in Sublinear Time}}}, doi = {{10.1007/11523468_70}}, year = {{2005}}, } @inproceedings{18787, abstract = {{A dynamic geometric data stream consists of a sequence of m insert/delete operations of points from the discrete space {1,..., ∆} d [26]. We develop streaming (1 + ɛ)-approximation algorithms for k-median, k-means, MaxCut, maximum weighted matching (MaxWM), maximum travelling salesperson (MaxTSP), maximum spanning tree (MaxST), and average distance over dynamic geometric data streams. Our algorithms maintain a small weighted set of points (a coreset) that approximates with probability 2/3 the current point set with respect to the considered problem during the m insert/delete operations of the data stream. They use poly(ɛ −1, log m, log ∆) space and update time per insert/delete operation for constant k and dimension d. Having a coreset one only needs a fast approximation algorithm for the weighted problem to compute a solution quickly. In fact, even an exponential algorithm is sometimes feasible as its running time may still be polynomial in n. For example one can compute in poly(log n, exp(O((1+log(1/ɛ)/ɛ) d−1))) time a solution to k-median and k-means [21] where n is the size of the current point set and k and d are constants. Finding an implicit solution to MaxCut can be done in poly(log n, exp((1/ɛ) O(1))) time. For MaxST and average distance we require poly(log n, ɛ −1) time and for MaxWM we require O(n 3) time to do this.}}, author = {{Sohler, Christian and Frahling, Gereon}}, booktitle = {{Proceedings of the 37th ACM Symposium on Theory of Computing (STOC)}}, pages = {{209--217}}, title = {{{Coresets in Dynamic Geometric Data Streams}}}, year = {{2005}}, } @article{18790, author = {{Czumaj, Artur and Sohler, Christian}}, issn = {{0304-3975}}, journal = {{Theoretical Computer Science}}, number = {{1}}, pages = {{37--52}}, title = {{{Testing hypergraph colorability}}}, doi = {{10.1016/j.tcs.2004.09.031}}, volume = {{331}}, year = {{2005}}, } @article{18855, abstract = {{We consider the problem of computing the weight of a Euclidean minimum spanning tree for a set of n points in $\mathbb R^d$. We focus on the setting where the input point set is supported by certain basic (and commonly used) geometric data structures that can provide efficient access to the input in a structured way. We present an algorithm that estimates with high probability the weight of a Euclidean minimum spanning tree of a set of points to within $1 + \eps$ using only $\widetilde{\O}(\sqrt{n} \, \text{poly} (1/\eps))$ queries for constant d. The algorithm assumes that the input is supported by a minimal bounding cube enclosing it, by orthogonal range queries, and by cone approximate nearest neighbor queries. Read More: https://epubs.siam.org/doi/10.1137/S0097539703435297 }}, author = {{Czumaj, Artur and Ergün, Funda and Fortnow, Lance and Magen, Avner and Newman, Ilan and Rubinfeld, Ronitt and Sohler, Christian}}, issn = {{0097-5397}}, journal = {{SIAM Journal on Computing}}, number = {{1}}, pages = {{91--109}}, title = {{{Approximating the Weight of the Euclidean Minimum Spanning Tree in Sublinear Time}}}, doi = {{10.1137/s0097539703435297}}, volume = {{35}}, year = {{2005}}, } @inproceedings{18867, abstract = {{Modern computer graphics systems are able to render sophisticated 3D szenes consisting of millions of polygons. In this paper we address the problem of occlusion culling. Aila, Miettinen, and Nordlund suggested to implement a FIFO buffer on graphics cards which is able to delay the polygons before drawing them. When one of the polygons within the buffer is occluded or masked by another polygon arriving later from the application, the rendering engine can drop the occluded one without rendering, saving important rendering time.
We introduce a theoretical online model to analyse these problems in theory using competitive analysis. For different cost measures addressed we invent the first competitive algorithms for online occlusion culling. Our implementation shows that these algorithms outperform known ones for real 3D scenes as well.}}, author = {{Frahling, Gereon and Krokowski, Jens}}, booktitle = {{Proc. of the 13th Annual European Symposium on Algorithms (ESA 2005)}}, isbn = {{9783540291183}}, issn = {{0302-9743}}, pages = {{758--769}}, publisher = {{Springer}}, title = {{{Online Occlusion Culling}}}, doi = {{10.1007/11561071_67}}, volume = {{3669}}, year = {{2005}}, } @inproceedings{18912, abstract = {{We consider Dynamic Page Migration (DPM) problem, one of the fundamental subproblems of data management in dynamically changing networks. We investigate a hybrid scenario, where access patterns to the shared object are dictated by an adversary, and each processor performs a random walk in X. We extend the previous results of [4]: we develop algorithms for the case where X is a ring, and prove that with high probability they achieve a competitive ratio of O~(min{D−−√4,n}), where D is the size of the shared object and n is the number of nodes in the network. These results hold also for any d-dimensional torus or mesh with diameter at least Ω~(D−−√).}}, author = {{Bienkowski, Marcin and Korzeniowski, Miroslaw}}, booktitle = {{Proc. of the European Conference in Parallel Processing (Euro-Par)}}, isbn = {{9783540287001}}, issn = {{0302-9743}}, title = {{{Dynamic Page Migration Under Brownian Motion}}}, doi = {{10.1007/11549468_105}}, year = {{2005}}, }