@inproceedings{18925, abstract = {{The dynamic page migration problem citedynamic-page-migration is defined in
a distributed network of $n$ mobile nodes sharing one indivisible memory page
of size $D$. During runtime, the nodes can both access a unit of data from
the page and move with a constant speed, thus changing the costs of communication.
The problem is to compute online a schedule of page movements
to minimize the total communication cost.

In this paper we construct and analyze the first deterministic algorithm for this problem.
We prove that it achieves an (up to a constant factor) optimal competitive ratio
$O(n cdot sqrtD)$. We show that the randomization of this algorithm
improves this ratio to $O(sqrtD cdot log n)$ (against an oblivious adversary).
This substantially improves an $O(n cdot sqrtD)$ upper bound from citedynamic-page-migration.
We also give an almost matching lower bound of $Omega(sqrtD cdot sqrtlog n)$ for this problem.}}, author = {{Bienkowski, Marcin and Dynia, Miroslaw and Korzeniowski, Miroslaw}}, booktitle = {{Proc. of the 22nd Symposium on Theoretical Aspects of Computer Science (STACS)}}, isbn = {{9783540249986}}, issn = {{0302-9743}}, pages = {{365--376}}, title = {{{Improved Algorithms for Dynamic Page Migration}}}, doi = {{10.1007/978-3-540-31856-9_30}}, year = {{2005}}, } @inbook{17988, author = {{Köhler, Sven and Schindelhauer, Christian and Ziegler, Martin}}, booktitle = {{Fundamentals of Computation Theory}}, isbn = {{9783540281931}}, issn = {{0302-9743}}, title = {{{On Approximating Real-World Halting Problems}}}, doi = {{10.1007/11537311_40}}, year = {{2005}}, } @inbook{17989, author = {{Meer, Klaus and Ziegler, Martin}}, booktitle = {{Fundamentals of Computation Theory}}, isbn = {{9783540281931}}, issn = {{0302-9743}}, title = {{{An Explicit Solution to Post’s Problem over the Reals}}}, doi = {{10.1007/11537311_41}}, year = {{2005}}, } @inproceedings{18280, abstract = {{The sometimes so-called Main Theorem of Recursive Analysis implies that any computable real function is necessarily continuous. We consider three relaxations of this common notion of real computability for the purpose of treating also discontinuous functions f:R->R:
*) non-deterministic computation;
*) relativized computation, specifically given access to oracles like 0' or 0'';
*) encoding input x and/or output y=f(x) in weaker ways according to the Real Arithmetic Hierarchy.
It turns out that, among these approaches, only the first one provides the required power.}}, author = {{Ziegler, Martin}}, booktitle = {{Proc. CiE 2005: New Computational Paradigms}}, isbn = {{9783540261797}}, issn = {{0302-9743}}, pages = {{562--571}}, publisher = {{Springer}}, title = {{{Computability and Continuity on the Real Arithmetic Hierarchy and the Power of Type-2 Nondeterminism}}}, doi = {{10.1007/11494645_68}}, volume = {{3526}}, year = {{2005}}, } @inbook{16468, author = {{Bienkowski, Marcin and Korzeniowski, Miroslaw and Meyer auf der Heide, Friedhelm}}, booktitle = {{Peer-to-Peer Systems IV}}, isbn = {{9783540290681}}, issn = {{0302-9743}}, title = {{{Dynamic Load Balancing in Distributed Hash Tables}}}, doi = {{10.1007/11558989_20}}, year = {{2005}}, } @inbook{16469, author = {{Bienkowski, Marcin and Meyer auf der Heide, Friedhelm}}, booktitle = {{Mathematical Foundations of Computer Science 2005}}, isbn = {{9783540287025}}, issn = {{0302-9743}}, title = {{{Page Migration in Dynamic Networks}}}, doi = {{10.1007/11549345_1}}, year = {{2005}}, } @inproceedings{16470, abstract = {{We present a web computing library (PUBWCL) in Java that allows to execute strongly coupled, massively parallel algorithms in the bulk-synchronous (BSP) style on PCs distributed over the internet whose owners are willing to donate their unused computation power. PUBWCL is realized as a peer-to-peer system and features migration and restoration of BSP processes executed on it. The use of Java guarantees a high level of security and makes PUBWCL platform independent. In order to estimate the loss of efficiency inherent in such a Java-based system, we have compared it to our C-based PUB-Library. }}, author = {{Bonorden, Olaf and Gehweiler, Joachim and Meyer auf der Heide, Friedhelm}}, booktitle = {{Proceeedings of 6th International Conference on Parallel Processing and Applied Mathematics (PPAM)}}, isbn = {{9783540341413}}, issn = {{0302-9743}}, pages = {{801--808}}, title = {{{A Web Computing Environment for Parallel Algorithms in Java}}}, doi = {{10.1007/11752578_96}}, year = {{2005}}, } @inproceedings{16471, abstract = {{We compare different load balancing strategies for Bulk-Synchronous Parallel (BSP) programs in a web computing environment. In order to handle the influence of the fluctuating available computation power, we classify the external work load. We evaluate the load balancing algorithms using our web computing library for BSP programs in Java (PUBWCL). Thereby we simulated the external work load in order to have repeatable testing conditions. With the best performing load balancing strategy we could save 39% of the execution time averaged and even up to 50% in particular cases.}}, author = {{Bonorden, Olaf and Gehweiler, Joachim and Meyer auf der Heide, Friedhelm}}, booktitle = {{Proceeedings of 6th International Conference on Parallel Processing and Applied Mathematics (PPAM)}}, isbn = {{9783540341413}}, issn = {{0302-9743}}, pages = {{839--846}}, title = {{{Load Balancing Strategies in a Web Computing Environment}}}, doi = {{10.1007/11752578_101}}, year = {{2005}}, } @inproceedings{15156, author = {{Böttcher, Stefan and Steinmetz, Rita}}, booktitle = {{Secure Data Management, Second VLDB Workshop, SDM 2005}}, isbn = {{9783540287988}}, issn = {{0302-9743}}, pages = {{143--154}}, publisher = {{Springer}}, title = {{{Detecting Privacy Violations in Sensitive XML Databases}}}, doi = {{10.1007/11552338_10}}, year = {{2005}}, } @inproceedings{19692, author = {{Briest, Patrick and Brockhoff, Dimo and Degener, Bastian and Englert, Matthias and Gunia, Christian and Heering, Oliver and Jansen, Thomas and Leifhelm, Michael and Plociennik, Kai and Röglin, Heiko and Schweer, Andrea and Sudholt, Dirk and Tannenbaum, Stefan and Wegener, Ingo}}, booktitle = {{Parallel Problem Solving from Nature - PPSN VIII}}, isbn = {{9783540230922}}, issn = {{0302-9743}}, title = {{{The Ising Model: Simple Evolutionary Algorithms as Adaptation Schemes}}}, doi = {{10.1007/978-3-540-30217-9_4}}, year = {{2004}}, } @inbook{3011, author = {{Blömer, Johannes and Guajardo, Jorge and Krummel, Volker}}, booktitle = {{Selected Areas in Cryptography}}, isbn = {{9783540243274}}, issn = {{0302-9743}}, pages = {{69--83}}, publisher = {{Springer Berlin Heidelberg}}, title = {{{Provably Secure Masking of AES}}}, doi = {{10.1007/978-3-540-30564-4_5}}, year = {{2004}}, } @inbook{3012, author = {{Blömer, Johannes and May, Alexander}}, booktitle = {{Public Key Cryptography – PKC 2004}}, isbn = {{9783540210184}}, issn = {{0302-9743}}, pages = {{1--13}}, publisher = {{Springer Berlin Heidelberg}}, title = {{{A Generalized Wiener Attack on RSA}}}, doi = {{10.1007/978-3-540-24632-9_1}}, year = {{2004}}, } @inbook{3014, author = {{May, Alexander}}, booktitle = {{Public Key Cryptography – PKC 2004}}, isbn = {{9783540210184}}, issn = {{0302-9743}}, pages = {{218--230}}, publisher = {{Springer Berlin Heidelberg}}, title = {{{Secret Exponent Attacks on RSA-type Schemes with Moduli N=p^{r}q}}}, doi = {{10.1007/978-3-540-24632-9_16}}, year = {{2004}}, } @inbook{3015, author = {{May, Alexander}}, booktitle = {{Advances in Cryptology – CRYPTO 2004}}, isbn = {{9783540226680}}, issn = {{0302-9743}}, pages = {{213--219}}, publisher = {{Springer Berlin Heidelberg}}, title = {{{Computing the RSA Secret Key Is Deterministic Polynomial Time Equivalent to Factoring}}}, doi = {{10.1007/978-3-540-28628-8_13}}, year = {{2004}}, } @inproceedings{18778, abstract = {{Given a point set P in the d-dimensional unit hypercube, we give upper bounds on the maximal expected number of extreme points when each point is perturbed by small random noise chosen independently for each point from the same noise distribution Δ. Our results are parametrized by the variance of the noise distribution. For large variance we essentially consider the average case for distribution Δ while for variance 0 we consider the worst case. Hence our results give upper bounds on the number of extreme points where our input distributions range from average case to worst case.
Our main contribution is a rather general lemma that can be used to obtain upper bounds on the expected number of extreme points for a large class of noise distributions. We then apply this lemma to obtain explicit bounds for random noise coming from the Gaussian normal distribution of variance σ² and the uniform distribution in a hypercube of side length &epsilon. For these noise distributions we show upper bounds of O( (1/ σ )^d * log^3/2 * d - 1 n ) and O( ( (n log n) / ε )^d/(d+1) ), respectively. Besides its theoretical motivation our model is also motivated by the observation that in many applications of convex hull algorithms the input data is inherently noisy, e.g. when the data comes from physical measurement or imprecise arithmetic is used.}}, author = {{Damerow, Valentina and Sohler, Christian}}, booktitle = {{Proceedings of the 12th European Symposium on Algorithms (ESA'04)}}, isbn = {{9783540230250}}, issn = {{0302-9743}}, title = {{{Extreme Points Under Random Noise}}}, doi = {{10.1007/978-3-540-30140-0_25}}, year = {{2004}}, } @inproceedings{18263, abstract = {{We generalize univariate multipoint evaluation of polynomials of degree n at sublinear amortized cost per point. More precisely, it is shown how to evaluate a bivariate polynomial p of maximum degree less than n, specified by its n^2 coefficients, simultaneously at n^2 given points using a total of O(n^2.667) arithmetic operations. In terms of the input size N being quadratic in n, this amounts to an amortized cost of O(N^0.334) per point.}}, author = {{Nüsken, Michael and Ziegler, Martin}}, booktitle = {{Proc. 12th Annual Symposium on Algorithms (ESA'04)}}, isbn = {{9783540230250}}, issn = {{0302-9743}}, pages = {{544--555}}, publisher = {{Springer}}, title = {{{Fast Multipoint Evaluation of Bivariate Polynomials}}}, doi = {{10.1007/978-3-540-30140-0_49}}, volume = {{3221}}, year = {{2004}}, } @inproceedings{18279, abstract = {{For $c in REAL$, a $c$-spanner is a subgraph of a complete Euclidean graph satisfying that between any two vertices there exists a path of weighted length at most $c$ times their geometric distance. Based on this property to approximate a complete weighted graph, sparse spanners have found many applications, e.g., in FPTAS, geometric searching, and radio networks. For geometric searching, it turned out to suffice whether the radius rather than the length of some path between any two vertices is bounded relatively to their geometric distance; this is the defining property of weak spanners. Finally regarding radio network applications, a power spanner accounts for the total energy afforded for a wireless transmission with the requirement that the sum of the squares of the lengths of some path between any two planar vertices must be bounded relatively to the square of their geometric distance (or higher powers up to 6 or even 8).

While it is known that any $c$-spanner is also both a weak $C_1$-spanner and a $C_2$-power spanner (for appropriate $C_1,C_2$ depending only on $c$ but not on the graph under consideration), we show that the converse fails: There exists a family of $c_1$-power spanners that are no weak $C$-spanners and also a family of weak $c_2$-spanners that are no $C$-spanners for any fixed $C$ (and thus no uniform spanners, either). However the deepest result of the present work reveals that, surprisingly, any weak spanner is also a uniform power spanner. We further generalize the latter notion by considering $(c,delta)$-power spanners where the sum of the $delta$-th powers of the lengths has to be bounded; so $(cdot,2)$-power spanners coincide with the usual power spanners and $(cdot,1)$-power spanners are classical spanners. Interestingly, these $(cdot,delta)$-power spanners form a strict hierarchy where the above results still hold for any $deltageq2$; some even hold for $delta>1$ while counterexamples reveal others to fail for $delta<2$. In fact we show that in general every self-similar curve of fractal dimension $d>delta$ is no $(C,delta)$-power spanner for any fixed $C$. }}, author = {{Schindelhauer, Christian and Volbert, Klaus and Ziegler, Martin}}, booktitle = {{Proc. of 15th Annual International Symposium on Algorithms and Computation (ISAAC'04)}}, isbn = {{9783540241317}}, issn = {{0302-9743}}, pages = {{805--821}}, publisher = {{Springer }}, title = {{{Spanners, Weak Spanners, and Power Spanners for Wireless Networks}}}, doi = {{10.1007/978-3-540-30551-4_69}}, volume = {{3341}}, year = {{2004}}, } @inproceedings{16474, abstract = {{Given n distinct points p1, p2, ... , pn in the plane, the map labeling problem with four squares is to place n axis-parallel equi-sized squares Q1, ... ,Qn of maximum possible size such that pi is a corner of Qi and no two squares overlap. This problem is NP-hard and no algorithm with approximation ratio better than 1/2 exists unless P = NP [10]. In this paper, we consider a scenario where we want to visualize the information gathered by smart dust, i.e. by a large set of simple devices, each consisting of a sensor and a sender that can gather sensor data and send it to a central station. Our task is to label (the positions of) these sensors in a way described by the labeling problem above. Since these devices are not positioned accurately (for example, they might be dropped from an airplane), this gives rise to consider the map labeling problem under the assumption, that the positions of the points are not fixed precisely, but perturbed by random noise. In other words, we consider the smoothed complexity of the map labeling problem. We present an algorithm that, under such an assumption and Gaussian random noise with sufficiently large variance, has linear smoothed complexity.}}, author = {{Bansal, Vikas and Meyer auf der Heide, Friedhelm and Sohler, Christian}}, booktitle = {{12th Annual European Symposium on Algorithms (ESA 2004)}}, isbn = {{9783540230250}}, issn = {{0302-9743}}, title = {{{Labeling Smart Dust}}}, doi = {{10.1007/978-3-540-30140-0_9}}, volume = {{3221}}, year = {{2004}}, } @inproceedings{13618, author = {{Walder, Herbert and Platzner, Marco}}, booktitle = {{Proceedings of the 14th International Conference on Field Programmable Logic and Applications (FPL)}}, isbn = {{9783540229896}}, issn = {{0302-9743}}, pages = {{831--835}}, publisher = {{Springer}}, title = {{{A Runtime Environment for Reconfigurable Hardware Operating Systems}}}, doi = {{10.1007/978-3-540-30117-2_84}}, year = {{2004}}, } @inbook{3016, author = {{Blömer, Johannes and May, Alexander}}, booktitle = {{Advances in Cryptology - CRYPTO 2003}}, isbn = {{9783540406747}}, issn = {{0302-9743}}, pages = {{27--43}}, publisher = {{Springer Berlin Heidelberg}}, title = {{{New Partial Key Exposure Attacks on RSA}}}, doi = {{10.1007/978-3-540-45146-4_2}}, year = {{2003}}, }