@misc{Weiser2009, author = {Weiser, Martin}, title = {On goal-oriented adaptivity for elliptic optimal control problems}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11192}, number = {09-08}, year = {2009}, abstract = {The paper proposes goal-oriented error estimation and mesh refinement for optimal control problems with elliptic PDE constraints using the value of the reduced cost functional as quantity of interest. Error representation, hierarchical error estimators, and greedy-style error indicators are derived and compared to their counterparts when using the all-at-once cost functional as quantity of interest. Finally, the efficiency of the error estimator and generated meshes are demonstrated on numerical examples.}, language = {en} } @misc{Kruber2009, type = {Master Thesis}, author = {Kruber, Nico}, title = {DHT Load Balancing with Estimated Global Information}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11514}, school = {Zuse Institute Berlin (ZIB)}, year = {2009}, abstract = {One of the biggest impacts on the performance of a Distributed Hash Table (DHT), once established, is its ability to balance load among its nodes. DHTs supporting range queries for example suffer from a potentially huge skew in the distribution of their items since techniques such as consistent hashing can not be applied. Thus explicit load balancing schemes need to be deployed. Several such schemes have been developed and are part of recent research, most of them using only information locally available in order to scale to arbitrary systems. Gossiping techniques however allow the retrieval of fairly good estimates of global information with low overhead. Such information can then be added to existing load balancing algorithms that can use the additional knowledge to improve their performance. Within this thesis several schemes are developed that use global information like the average load and the standard deviation of the load among the nodes to primarily reduce the number of items an algorithm moves to achieve a certain balance. Two novel load balancing algorithms have then been equipped with implementations of those schemes and have been simulated on several scenarios. Most of these variants show better balance results and move far less items than the algorithms they are based on. The best of the developed algorithms achieves a 15-30\% better balance and moves only about 50-70\% of the number of items its underlying algorithm moves. This variation is also very robust to erroneous estimates and scales linearly with the system size and system load. Further experiments with self-tuning algorithms that set an algorithm's parameter according to the system's state show that even more improvements can be gained if additionally applied. Such a variant based on the algorithm described by Karger and Ruhl shows the same balance improvements of 15-30\% as the variant above but reduces the number of item movements further to 40-65\%.}, language = {en} } @misc{GottwaldTolksdorf2009, author = {Gottwald, Susanne and Tolksdorf, Robert}, title = {Planning Teams with Semantic Web Technologies}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11523}, number = {09-33}, year = {2009}, abstract = {When planning teams for projects with specific goals, employees of a company have to group together so well, that all necessary knowledge for conquering the project's challenges are met within the member's skills. A tool that facilitates semantic web technologies can support the team recruiter, who is responsible for chosing the members of the team, in terms of finding the most efficient combinations of the company's employees based on their expertises.}, language = {en} } @misc{MoserHaridiShafaatetal.2009, author = {Moser, Monika and Haridi, Seif and Shafaat, Tallat and Sch{\"u}tt, Thorsten and H{\"o}gqvist, Mikael and Reinefeld, Alexander}, title = {Transactional DHT Algorithms}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11532}, number = {09-34}, year = {2009}, abstract = {We present a framework for transactional data access on data stored in a DHT. It allows to atomically read and write items and to run distributed transactions consisting of a sequence of read and write operations on the items. Items are symmetrically replicated in order to achieve durability of data stored in the SON. To provide availability of items despite the unavailability of some replicas, operations on items are quorum-based. They make progress as long as a majority of replicas can be accessed. Our framework processes transactions optimistically with an atomic commit protocol that is based on Paxos atomic commit. We present algorithms for the whole framework with an event based notation. Additionally we discuss the problem of lookup inconsistencies and its implications on the one-copy serializability property of the transaction processing in our framework.}, language = {en} } @misc{Kuberek2009, author = {Kuberek, Monika}, title = {Strategien f{\"u}r die Zukunft der regionalen Informationsinfrastruktur - der Kooperative Bibliotheksverbund Berlin-Brandenburg (KOBV)}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11546}, number = {09-35}, year = {2009}, abstract = {Eines der Hauptanliegen bei der Initiierung des Kooperativen Bibliotheksverbundes Berlin-Brandenburg (KOBV) war die Schaffung einer modernen, leistungsf{\"a}higen Informationsinfrastruktur unter Einbeziehung m{\"o}glichst aller Bibliotheken der in ihrer Dichte und Vielfalt in Deutschland einmaligen Bibliothekslandschaft. Sie wurde beim Aufbau des KOBV durch die Wahl des Verbundmodelles mit seinen offenen, integrativen Strukturen bef{\"o}rdert. Die Ziele und Strategien des KOBV leiten sich aus dem Grundauftrag der Bibliotheken her, ihre NutzerInnen optimal mit Medien und Informationen zu versorgen. Mit dem KOBV haben die Bibliotheken eine gemeinsame Plattform und ein regionales Netzwerk geschaffen, mit deren Hilfe sie die Informationsinfrastruktur in Berlin und Brandenburg zusammen aufgebaut und grundlegend verbessert haben. Nach rund elf Jahren ist der KOBV in eine neue Phase eingetreten, indem er - unter Wahrung seiner institutionellen Eigenst{\"a}ndigkeit - eine Strategische Allianz mit dem Bibliotheksverbund Bayern (BVB) eingegangen ist und die bislang auf die Region bezogene Kooperation der Bibliotheken {\"u}berregional ausgeweitet hat. Wenn auch die Universalbibliotheken des KOBV in dieser Zusammenarbeit einen Kurswechsel zur zentralen Katalogisierung vollziehen, bedeutet dies f{\"u}r den KOBV insgesamt keinen Paradigmenwechsel: Er bleibt ein dezentraler Verbund und wird sein flexibles technisches Mischkonzept von verteilter und zentraler Datenhaltung fortf{\"u}hren. Dieses l{\"a}sst den Bibliotheken die Freiheit zu entscheiden, ob sie zentral oder dezentral katalogisieren m{\"o}chten. Die KOBV-Zentrale, die im KOBV keine Aufgaben in der Katalogisierung wahrnimmt, wird wie bislang allen Mitgliedsbibliotheken die ASP-Dienste und weiteren Angebote gleichermaßen zur Verf{\"u}gung stellen und die Dienstleistungen f{\"u}r NutzerInnen und Bibliotheken weiter ausbauen. Mit dem vorhandenen Know How, der eingesetzten modernen Technologie und der strategischen Entscheidung, Ressourcen und Kompetenzen mit dem BVB zu b{\"u}ndeln und durch verbund{\"u}bergreifende arbeitsteilige Verfahren Synergien zu gewinnen, ist der KOBV gut aufgestellt, um die Herausforderungen der kommenden Jahre anzugehen und das Leistungsspektrum der KOBV-Bibliotheken durch die Entwicklung neuer Dienste auszuweiten.}, language = {de} } @misc{Mauter2009, type = {Master Thesis}, author = {Mauter, Daniel}, title = {Ein eingebettetes Hauptspeicher-Datenbanksystem mit Snapshot-Reads}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11552}, school = {Zuse Institute Berlin (ZIB)}, year = {2009}, abstract = {Entwurf und Entwicklung eines eingebetteten Hauptspeicher-Datenbanksystems mit Snapshot-Reads.}, language = {de} } @misc{SchielaWeiser2009, author = {Schiela, Anton and Weiser, Martin}, title = {Barrier methods for a control problem from hyperthermia treatment planning}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11567}, number = {09-36}, year = {2009}, abstract = {We consider an optimal control problem from hyperthermia treatment planning and its barrier regularization. We derive basic results, which lay the groundwork for the computation of optimal solutions via an interior point path-following method. Further, we report on a numerical implementation of such a method and its performance at an example problem.}, language = {en} } @misc{Woelk2009, type = {Master Thesis}, author = {W{\"o}lk, Bertram}, title = {Generierung hybrider Gitter f{\"u}r die Str{\"o}mungssimulation auf komplexen anatomischen Geometrien}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11588}, school = {Zuse Institute Berlin (ZIB)}, year = {2009}, abstract = {Basierend auf einem vorhandenen Ansatz zur Einf{\"u}hrung von anisotropen Tetraedern im Randbereich eines reinen Tetraedergitters wird ein Gittergenerator f{\"u}r hybride Gitter implementiert. Das hybride Gitter besteht in Randn{\"a}he prim{\"a}r aus anisotropen Prismen und im Inneren der Geometrie aus isotropen Tetraedern. Eine erh{\"o}hte Aufl{\"o}sung im Randbereich soll zu besseren Ergebnissen von numerischen Str{\"o}mungssimulationen f{\"u}hren, f{\"u}r welche eine problemangepasste Diskretisierung des zu untersuchenden Gebietes ben{\"o}tigt wird. In dem zuvor genannten Ansatz wird eine Reihe von {\"U}bergangselementen vorgeschlagen, die an scharfen Kanten der Oberfl{\"a}che platziert werden sollen. Im Rahmen dieser Diplomarbeit wird die Idee der {\"U}bergangselemente aufgegriffen und bei hybriden Gittern eingesetzt, um auch komplexe Eingabegeometrien vergittern zu k{\"o}nnen. Der urspr{\"u}ngliche Gittergenerierungprozess wird {\"u}berarbeitet und erweitert. Eine neue Menge an {\"U}bergangselementen wird eingef{\"u}hrt, es werden gekr{\"u}mmte Extrusionsvektoren verwendet und es wird die Auswertung der medialen Oberfl{\"a}che vorgenommen, um {\"U}berschneidungen im hybriden Gitter zu vermeiden. Der Gittergenerator wird als Modul in das Visualisierungs- und Analyseprogramm Amira implementiert und die erstellten hybriden Gitter werden auf ihre Elementqualit{\"a}t und die G{\"u}te der Str{\"o}mungssimulationsergebnisse hin {\"u}berpr{\"u}ft.}, language = {de} } @phdthesis{Zschiedrich2009, author = {Zschiedrich, Lin}, title = {Transparent boundary conditions for Maxwell's equations: Numerical concepts beyond the PML method}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:188-fudissthesis000000013994-8}, year = {2009}, abstract = {Optical technologies are ubiquitously used in hi-tech devices. As a common feature of such devices one finds structures with dimensions in the order of the wavelength of the used light. To design and produce such devices, the wave nature of light must be taken into account. Accordingly, robust simulation tools are required which are based on rigorously solving Maxwell's equations, the governing equations of light propagation within macroscopic media. This thesis contributes to the modeling and the numerical computation of light scattering problems: Light scattering problems are typically posed on the entire space. The Perfectly-Matched -Layer method (PML) is widely used to restrict the simulation problem onto a bounded computational domain. We propose an adaptive PML method which exhibits a good convergence even for critical problems where standard PML implementations fail. Besides the computation of the near field, that is the electromagnetic field within the computational domain, it is of major interest to evaluate the electromagnetic field in the exterior domain and to compute the far field. So far, this was numerically only possible for simple geometries such as homogeneous exterior domains or layered media. To deal with more complicated devices, for example with waveguide inhomogeneities, we develop an evaluation formula based on the PML solution which allows for an exterior domain field evaluation in a half space above the device. Finally, we generalize the PML method to problems with multiply structured exterior domains. The term "multiply structured exterior domain" is defined in this thesis and means that the exterior domain exhibits several half-infinite structures. Mathematically, this gives rise to various complications. For example, no analytical solutions to Maxwell's equations for standard light sources are available in the exterior domain, which are needed to describe the incoming field in a light scattering problem. To tackle this we propose a new light scattering problem formulation which fits well into the PML method framework and which may be regarded as an extension of classical contributions by Sommerfeld, Wiener and Hopf. An exterior domain evaluation formula for multiply structured exterior domains with an extended illumination is derived as well.}, language = {en} } @phdthesis{Roeblitz2009, author = {R{\"o}blitz, Susanna}, title = {Statistical Error Estimation and Grid-free Hierarchical Refinement in Conformation Dynamics}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:188-fudissthesis000000008079-9}, year = {2009}, abstract = {The understanding of geometric structures and dynamical properties of molecular conformations gives insight into molecular long-term behavior. The identification of metastable conformations together with their life times and transition patterns is the intention of conformation dynamics. Conformation dynamics is a multi-scale approach that leads to a reduced description of the dynamical system in terms of a stochastic transition probability matrix. The present thesis deals with the error analysis of computed matrices and the resulting matrix functions. Since conformational membership vectors, as they are computed by the Robust Perron Cluster Analysis (PCCA+), form an invariant subspace of the transition matrix, subspace-based error estimators are of particular interest. The decomposition of the state space into basis functions and the approximation of integrals by Monte-Carlo quadrature give rise to row-wise correlated random matrices, for which stochastic norms are computed. Together with an appropriate statistical model for the distribution of matrix rows, this allows for the calculation of error bounds and error distributions of the invariant subspace and other variables of interest. Equilibration of errors among the basis functions can be achieved by enhanced sampling in regions where the trajectories are mixing slowly. Hierarchical refinement of such basis functions systematically improves the clustering into metastable conformations by reducing the error in the corresponding invariant subspace. These techniques allow for an evaluation of simulation results and pave the way for the analysis of larger molecules. Moreover, the extension of PCCA+ to non-reversible Markov chains, verified by the corresponding perturbation theory, and the modification of the objective function for the case of soft membership vectors represent a further generalization of the clustering method, thus continuing the development from PCCA over PCCA+ to PCCA++. The methods developed in this thesis are useful for but not limited to conformation dynamics. In fact, they are applicable to a broader class of problems which combine domain decomposition with Monte-Carlo quadrature. Possible application areas may include the chemical master equation or quantum dynamical systems.}, language = {en} } @misc{KilianMuench2009, author = {Kilian, Susanne and M{\"u}nch, Matthias}, title = {A new generalized domain decomposition strategy for the efficient parallel solution of the FDS-pressure equation. Part I: Theory, Concept and Implementation}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11332}, number = {09-19}, year = {2009}, abstract = {A world-wide used program for the simulation of fire-induced flows is the Fire Dynamics Simulator (FDS) which originally was developed for a purely serial execution on single-processor computing systems. Due to steadily increasing problem sizes and accuracy requirements as well as restrictions in storage capacity and computing power on single-processor systems, the efficient simulation of the considered fire scenarios can only be achieved on modern high-performance systems based on multi-processor architectures. The transition to those systems requires the elaborate parallelization of the underlying numerical methods which must guarantee the same result for a given problem as the corresponding serial execution. Unfortunately, one fundamental serial serial solver of FDS, the pressure solver, only possesses a low degree of inherent parallelizm. Its current parallelization may cause additional numerical errors, casually leading to significant losses of accuracy or even numerical instabilities. In order to ensure that the parallelization errors are limited by the leading error of the numerical scheme such that second order convergence for the whole method can be acchieved, optimized parallelization concepts must be designed. With respect to these considerations this articles gives an overview of the current parallel pressure solver as well as the problems related to it and presents an alternative method, SCARC, to overcome the existing complicacies. Part I explains the theory, concept and implementation of this new strategy, whereas Part II describes a series of validation and verification tests to proof its correctness.}, language = {en} } @misc{MuenchKilian2009, author = {M{\"u}nch, Matthias and Kilian, Susanne}, title = {A new generalized domain decomposition strategy for the efficient parallel solution of the FDS-pressure equation. Part II: Verification and Validation}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11340}, number = {09-20}, year = {2009}, abstract = {Because CFD programs, like FDS, generally consist of a large number of different components representing the variety of participating numerical algorithms and chemical / physical processes, it is nearly impossible to verify such codes in their entirety, for example with comparisons of fire tests. Instead, a careful verification and validation with respect to the underlying mathematical conditions and applied numerical schemes is indispensable. In particular, error cancelations between single program components can only be detected by such detailed component-level tests. In part I of this article series a conceptual deficiency of the FDS program package with regard to multi-mesh computations was illustrated and an alternative domain decomposition strategy FDS-ScaRC was introduced. In this second part we will present the structure of a comprehensive test concept and the needs for a more mathematically and numerically orientated test procedure that is much more suited for a reliable evaluation than only a simple visual comparison of the numerical results with experimental fire tests. After a general introduction of our test concept we will demonstrate the high potential of the new FDS-\scarc{} technique compared to the FDS-FFT technique which is used in the FDS program package as yet. Based on this concept, we will present a comprehensive set of analytical and numerical test results.}, language = {en} } @misc{RuprechtKleinMajda2009, author = {Ruprecht, Daniel and Klein, Rupert and Majda, Andrew J.}, title = {Moisture-Gravity Wave Interactions in a Multiscale Environment}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11358}, number = {09-21}, year = {2009}, abstract = {Starting from the conservation laws for mass, momentum and energy together with a three species, bulk microphysic model, a model for the interaction of internal gravity waves and deep convective hot towers is derived by using multiscale asymptotic techniques. From the resulting leading order equations, a closed model is obtained by applying weighted averages to the smallscale hot towers without requiring further closure approximations. The resulting model is an extension of the linear, anelastic equations, into which moisture enters as the area fraction of saturated regions on the microscale with two way coupling between the large and small scale. Moisture reduces the effective stability in the model and defines a potential temperature sourceterm related to the net effect of latent heat release or consumption by microscale up- and downdrafts. The dispersion relation and group velocity of the system is analyzed and moisture is found to have several effects: It reduces energy transport by waves, increases the vertical wavenumber but decreases the slope at which wave packets travel and it introduces a lower horizontal cutoff wavenumber, below which modes turn into evanescent. Further, moisture can cause critical layers. Numerical examples for steadystate and timedependent mountain waves are shown and the effects of moisture on these waves are investigated.}, language = {en} } @misc{Massing2009, type = {Master Thesis}, author = {Massing, Andr{\´e}}, title = {1D-Reduktion thermal signifikanter Aderstr{\"a}nge in der Hyperthermie-Modellierung}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11407}, school = {Zuse Institute Berlin (ZIB)}, year = {2009}, abstract = {In dieser Arbeit wird ein neuer Ansatz zur Modellierung von thermal signifikanten Gef{\"a}ßstr{\"a}ngen im Hyperthermie-Kontext betrachtet. Ausgehend von einer Konvektions-Diffusions-Gleichung wird durch Reskalierung des Massenflussterms eine Reduktion des Adergebietes auf eine 1D-Struktur erreicht. Nach numerischen Vorbetrachtungen wird die Grenzgleichung innerhalb einer verallgemeinerten Sobolev-Algebra formuliert. Die Untersuchung der L{\"o}sungsfamilie in klassischen Funktionenr{\"a}umen zeigt, dass deren schwacher Grenzwert die L{\"o}sung der korrespondierenden Diffusions-Gleichung ist. Die Diskretisierung einer formalen Grenzgleichung mit Linienstromanteil stellt jedoch eine gute Approximation an die Diskretisierung des urspr{\"u}nglichen Problems dar, wenn man die lokale Maschenweite an die Gef{\"a}ßradien koppelt und bei erh{\"o}htem Genauigkeitsbedarf auf ein vollst{\"a}ndiges 3D-Modell umschaltet.}, language = {de} } @misc{SchmidtOevermannBastiaansetal.2009, author = {Schmidt, Heiko and Oevermann, Michael and Bastiaans, Rob J.M. and Kerstein, Alan R.}, title = {A Priori Tabulation of Turbulent Flame Speeds via a Combination of a Stochastic Mixing Model and Flamelet Generated Manifolds, Extended to Incorporate Strain Effects}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11214}, number = {09-09}, year = {2009}, abstract = {In this paper we revisit the a priori turbulent flame speed tabulation (TFST) technique for a given parameter space within the region of flamelet combustion-regimes. It can be used as a subgrid-scale (SGS) model in Large Eddy Simulation (LES). In a first step, stationary laminar flamelets are computed and stored over the progress variable following the ideas of flamelet generated manifolds (FGM). In a second step, the incompressible one-dimensional Navier-Stokes equations supplemented by the equation for the progress variable are solved on a grid that resolves all turbulent scales. Additionally, turbulent transport is implemented via the linear eddy model (LEM). The turbulent flame structures are solved until a statistically stationary mean value of the turbulent flame speed has been reached. The results are stored in a table that could be used by large scale premixed combustion models, e.g. front tracking schemes. First results are compared quantitatively with direct numerical simulations (DNS) taken from literature. Then it is illustrated in one example how the new method could help to fix constants in algebraic models for turbulent flame speeds. Further it is shown how the technique can be extended to incorporate turbulent strain effects. Finally we investigate the effect of the use of detailed and tabulated chemistry under unsteady conditions.}, language = {en} } @misc{GroetschelLuegger2009, author = {Gr{\"o}tschel, Martin and L{\"u}gger, Joachim}, title = {Ver{\"a}nderungen der Publikations- und Kommunikationswelt: Open Access, Google, etc.}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11223}, number = {09-10}, year = {2009}, abstract = {Vorbemerkung Beim Schreiben dieses Artikels, der auf Ver{\"a}nderungen der Kommunikations- und Publikationstechniken und ihre Bedeutung hinweist, ist uns mehr als je zuvor bewusst geworden, wie beschr{\"a}nkt das Medium Papier ist. Es gibt z. B. keine Hyperlinks, durch die man unmittelbar das Erw{\"a}hnte erleben oder {\"u}berpr{\"u}fen kann. Ein schneller Wechsel vom Wort zum Bild, zum Ton oder Video ist nicht m{\"o}glich. Wer will schon lange URLs abtippen und Medienbr{\"u}che erleiden? Wir haben uns daher entschlossen, eine textidentische Version dieses Artikels mit allen URLs - sie liegt Ihnen hier vor - elektronisch anzubieten und in der f{\"u}r die "Gegenworte" (BBAW) gek{\"u}rzten Fassung nur durch [URL] anzudeuten, dass der Leser an dieser Stelle einfach in der elektronischen Version einen Klick ins Internet machen sollte. Und damit sind wir bereits mitten im Thema.}, language = {de} } @misc{MaiwaldPetersKottig2009, author = {Maiwald, Gunar and Peters-Kottig, Wolfgang}, title = {Ergebnisse aus dem BVB-KOBV-Entwicklungsprojekt "Literaturverwaltungsprogramme": Handreichung f{\"u}r Bibliotheken}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11285}, number = {09-16}, year = {2009}, abstract = {Zwischen dem Bibliotheksverbund Bayern (BVB) und dem Kooperativen Bibliotheksverbund Berlin-Brandenburg (KOBV) besteht seit Ende 2007 eine Strategische Allianz, die auf zwei S{\"a}ulen beruht: einer langfristigen Entwicklungspartnerschaft einerseits und der Kooperation im Dienstleistungsbereich mit der Integration der Verbundkataloge andererseits. Ende 2008 wurde das erste Entwicklungsprojekt "Literaturverwaltungsprogramme" abgeschlossen, dessen Ergebnisse in dieser Handreichung in Form von Handlungsempfehlungen f{\"u}r Bibliotheken vorgestellt werden. Ziel des Projekts war es, den Datenaustausch zwischen den Bibliotheks- und Verbundkatalogen des BVB und KOBV und g{\"a}ngigen Literaturverwaltungsprogrammen zu optimieren. Neben Handlungsempfehlungen f{\"u}r die Implementierung neuer Exportschnittstellen und die Verbesserung bestehender Exportm{\"o}glichkeiten werden Hinweise auf verbesserte Nutzerf{\"u}hrung gegeben. Die Empfehlungen beziehen sich vorwiegend auf den Datenaustausch zwischen den Bibliothekssystemen Aleph 500, MetaLib und WebOPAC/InfoGuide und den Literaturverwaltungsprogrammen Citavi, EndNote, RefWorks und Zotero.}, language = {de} } @misc{TsarevWolf2009, author = {Tsarev, Sergey and Wolf, Thomas}, title = {Hyperdeterminants as integrable discrete systems}, issn = {1438-0064}, arxiv = {http://arxiv.org/abs/0903.3864}, doi = {10.1088/1751-8113/42/45/454023}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11292}, number = {09-17}, year = {2009}, abstract = {We give the basic definitions and some theoretical results about hyperdeterminants, introduced by A.~Cayley in 1845. We prove integrability (understood as \$4d\$-consistency) of a nonlinear difference equation defined by the \$2 \times 2 \times 2\$ - hyperdeterminant. This result gives rise to the following hypothesis: the difference equations defined by hyperdeterminants of any size are integrable. We show that this hypothesis already fails in the case of the \$2\times 2\times 2\times 2\$ - hyperdeterminant.}, language = {en} } @misc{OPUS4-1130, title = {Jahresbericht 2008}, issn = {0934-5892}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11307}, number = {2008}, year = {2009}, language = {de} } @misc{FranckKleinKubereketal.2009, author = {Franck, Hildegard and Klein, Thoralf and Kuberek, Monika and Lohrum, Stefan and Maiwald, Gunar}, title = {Automatisierte Fernleihe im KOBV - Handbuch f{\"u}r Bibliotheken - 3. Auflage}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11429}, number = {09-26}, year = {2009}, abstract = {Im Kooperativen Bibliotheksverbund Berlin-Brandenburg (KOBV) wird f{\"u}r die automatisierte Fernleihe der Zentrale-Fernleihserver (ZFL-Server) der Firma Sisis eingesetzt. Die Software ist in der KOBV-Zentrale installiert. Der ZFL-Server dient im KOBV sowohl f{\"u}r die Bestellung von Monographien als auch f{\"u}r die Bestellung von Aufsatzkopien aus Zeitschriften. Prinzipiell gibt es zwei Verfahren, mit denen sich Bibliotheken an der automatisierten Fernleihe beteiligen k{\"o}nnen: das E-Mail-Verfahren und das SLNP-Verfahren. Auf beide wird im Handbuch eingegangen. Die automatisierte Fernleihe wurde im KOBV eingef{\"u}hrt, um die Fernleihe f{\"u}r die Benutzer zu beschleunigen, das Verfahren f{\"u}r die Bibliotheksmitarbeiter zu vereinfachen und den Arbeitsaufwand zu reduzieren. Sie basiert darauf, dass eine Bestellung anhand eines gefundenen Treffers ausgel{\"o}st wird - d.h. die bibliographischen Daten sind bereits verifiziert und in einem Katalog nachgewiesen. Anschließend wird die Bestellung {\"u}ber den ZFL-Server automatisch ausgef{\"u}hrt und verwaltet - sowohl in der regionalen KOBV-Fernleihe als auch in der verbund{\"u}bergreifenden Fernleihe mit den deutschen Bibliotheksverb{\"u}nden. Der ZFL-Server besteht aus verschiedenen technischen Komponenten. Eine dieser Komponenten ist das Bibliothekskonto, eine Internetanwendung, in der die Bestellverwaltung des ZFL-Servers f{\"u}r die Bibliotheksbediensteten transparent abl{\"a}uft. Dazu hat jede Bibliothek im Bibliothekskonto eine eigene, Passwort-gesch{\"u}tzte Dienstoberfl{\"a}che. Im Laufe des Jahres 2009 hat die KOBV-Zentrale das Bibliothekskonto grundlegend {\"u}berarbeitet; die neue Version wurde im September 2009 freigegeben. Neben der {\"U}berabeitung des Interfaces - so wird den Bibliotheken auf der Startseite nun eine {\"U}bersicht ihrer laufenden Bestellungen angezeigt und dient als direkter Einstieg in die Bearbeitung - wurde das Bibliothekskonto um folgende Funktionen erweitert: Bestellung zur{\"u}cklegen (HOLD), Vormerkungen, Bestellungen zur Anfrage, Abbruch des Leitweges (auch verbund{\"u}bergreifend), erweiterte Kommentarfunktion, Bestellnummernsuche in allen Verb{\"u}nden. Das Handbuch, das die Vorg{\"a}nge der Bestellverwaltung im Bibliothekskonto beschreibt, wurde in der nun vorliegenden 3. Auflage um die Beschreibung der neuen Funktionen erg{\"a}nzt. An dieser Stelle ein Dank an die Kolleginnen und Kollegen aus den KOBV-Bibliotheken - Frau Bruske (UB der Freien Universit{\"a}t Berlin), Frau Ebert (UB der Europa-Universit{\"a}t Viadrina Frankfurt (Oder)), Frau Preuß (UB der Technischen Universit{\"a}t Berlin) und Herrn Ringmayer (Zentral- und Landesbibliothek Berlin) - f{\"u}r die tatkr{\"a}ftige Unterst{\"u}tzung bei der Entwicklung der neuen Funktionen.}, language = {de} } @misc{Weber2009, author = {Weber, Marcus}, title = {A Subspace Approach to Molecular Markov State Models via an Infinitesimal Generator}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11432}, number = {09-27}, year = {2009}, abstract = {Supercomputers can simulate complex molecular systems. However, there is a very large gap between the fastest oscillations of covalent bonds of a molecule and the time-scale of the dominant processes. In order to extract the dominant time-scales and to identify the dominant processes, a clustering of information is needed. This thesis shows that only the subspace-based Robust Perron Cluster Analysis (PCCA+) can solve this problem correctly by the construction of a Markov State Model. PCCA+ allows for time-extrapolation in molecular kinetics. This thesis shows the difference between molecular dynamics and molecular kinetics. Only in the molecular kinetics framework a definition of transition rates is possible. In this context, the existence of an infinitesimal generator of the dynamical processes is discussed. If the existence is assumed, the Theorem of Gauß can be applied in order to compute transition rates efficiently. Molecular dynamics, however, is not able to provide a suitable statistical basis for the determination of the transition pattern.}, language = {en} }