P180 - BTW2011 - Datenbanksysteme für Business, Technologie und Web
Auflistung nach:
Auflistung P180 - BTW2011 - Datenbanksysteme für Business, Technologie und Web nach Erscheinungsdatum
1 - 10 von 57
Treffer pro Seite
Sortieroptionen
- Editiertes Buch
- KonferenzbeitragQSQLp: Eine Erweiterung der probabilistischen Many-World- Semantik um Relevanzwahrscheinlichkeiten(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Lehrack, Sebastian; Saretz, Sascha; Schmitt, IngoDie traditionelle Auswertung einer Datenbankanfrage ermittelt für jedes Tupel entweder den Wahrheitswert Wahr oder Falsch. Für viele Anwendungsszenarien ist diese Auswertungssemantik zu restriktiv, insbesondere wenn ein differenzierteres Anfrageergebnis benö- tigt wird. Ein etablierter probabilistischer Ansatz zum Erreichen dieser Ausdifferenzierung ist die Verwendung sogenannter Relevanzwahrscheinlichkeiten: Mit welcher Wahrscheinlichkeit ist ein Dokument oder ein Datenobjekt bezüglich einer gestellten Anfrage relevant? Neben den IR-motivierten Relevanzwahrscheinlichkeiten hat sich in der Datenbankforschung das Gebiet der probabilistischen Datenbanken etabliert. Auch hier wird ein striktes, deterministisches Auswertungsmodell als nicht mehr ausreichend angesehen. In probabilistischen Datenbanksystemen werden daher mehrere mögliche Zustände für ein und dasselbe System in einer gemeinsamen Datenbank verwaltet. Die vorliegende Arbeit verbindet diese beiden probabilistischen Ansätze zu einem semantisch reicheren Anfragemodell.
- KonferenzbeitragMapReduce and PACT - comparing data parallel programming models(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Alexandrov, Alexander; Ewen, Stephan; Heimel, Max; Hueske, Fabian; Kao, Odej; Markl, Volker; Nijkamp, Erik; Warneke, DanielWeb-Scale Analytical Processing is a much investigated topic in current research. Next to parallel databases, new flavors of parallel data processors have recently emerged. One of the most discussed approaches is MapReduce. MapReduce is highlighted by its programming model: All programs expressed as the second-order functions map and reduce can be automatically parallelized. Although MapReduce provides a valuable abstraction for parallel programming, it clearly has some deficiencies. These become obvious when considering the tricks one has to play to express more complex tasks in MapReduce, such as operations with multiple inputs. The Nephele/PACT system uses a programming model that pushes the idea of MapReduce further. It is centered around so called Parallelization Contracts (PACTs), which are in many cases better suited to express complex operations than plain MapReduce. By the virtue of that programming model, the system can also apply a series of optimizations on the data flows before they are executed by the Nephele runtime system. This paper compares the PACT programming model with MapReduce from the perspective of the programmer, who specifies analytical data processing tasks. We discuss the implementations of several typical analytical operations both with MapReduce and with PACTs, highlighting the key differences in using the two programming models.
- KonferenzbeitragFeature-based graph similarity with co-occurrence histograms and the earth mover's distance(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Wichterich, Marc; Ivanescu, Anca Maria; Seidl, ThomasGraph structures are utilized to represent a wide range of objects including naturally graph-like objects such as molecules and derived graph structures such as connectivity graphs for region-based image retrieval. This paper proposes to extend the applicability of the Earth Mover's Distance [RTG98] (EMD) to graph objects by deriving a similarity model with a representation of structural graph features that is compatible with the feature signatures of the EMD. The aim is to support the search for a graph in a database from which the query graph may have originated through limited structural modification. Such query graphs with missing or additional vertices or edges may be the result of natural processes of decay or mutation or may stem from measuring methods that are inherently error-prone, to name a few examples.
- KonferenzbeitragImproving service discovery through enriched service descriptions(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) AbuJarour, Mohammed; Naumann, FelixThe increasing popularity of the Software-as-a-Service and Cloud Computing trends has been among the main factors behind the increasing number of public web services in several domains, e.g., e-commerce, enterprise, education, government, etc. Moreover, the functionalities of such web services are becoming more complex due to the complexities of modern business needs and marketplaces. Additionally, it has been observed that service providers, who represent the single source of information about web services, typically release poor service descriptions. Due to the aforementioned factors, service discovery has become one of the main challenges in Service-oriented Computing (SOC). In this demo, we show how to enrich service descriptions enabling enhanced service discovery. In our approach, web services are enriched with annotations (textual descriptions and tags) that are automatically extracted from the websites of their providers and from the analysis of their invocations.
- KonferenzbeitragStreamCars – Datenstrommanagementbasierte Verarbeitung von Sensordaten im Fahrzeug(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Bolles, André; Geesen, Dennis; Grawunder, Marcro; Jacobi, Jonas; Nicklas, Daniela; Appelrath, Hans-Jürgen; Hannibal, Marco; Köster, FrankWir präsentieren StreamCars, eine datenstrommanagementbasierte Architektur für die flexible Verarbeitung von Sensordaten im Fahrzeug. Das Datenstrommanagementsystem Odysseus stellt Anfrageverarbeitungsmechanismen zur Objektverfolgung und zum Aufbau eines Kontextmodells bereit. Auf dieses wird dann über kontinuierliche Datenstromanfragen zugegriffen, sodass spezifische Informationen an unterschiedliche Assistenzfunktionen in Fahrzeugen weitergeleitet werden können.
- KonferenzbeitragOnline hot spot prediction in road networks(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Häsner, Maik; Junghans, Conny; Sengstock, Christian; Gertz, MichaelAdvancements in GPS-technology have spurred major research and development activities for managing and analyzing large amounts of position data of mobile objects. Data mining tasks such as the discovery of movement patterns, classification and outlier detection in the context of object trajectories, and the prediction of future movement patterns have become basic tools in extracting useful information from such position data. Especially the prediction of future movement patterns of vehicles, based on historical or recent position data, plays an important role in traffic management and planning. In this paper, we present a new approach for the online prediction of so-called hot spots, that is, components of a road network such as intersections that are likely to experience heavy traffic in the near future. For this, we employ an efficient path prediction model for vehicle movements that only utilizes a few recent position data. Using an aggregation model for hot spots, we show how regional information can be derived and connected substructures in a road network can be determined. Utilizing the behavior of such hot spot regions over time in terms of movement or growth, we introduce different types of hot spots and show how they can be determined online. We demonstrate the effectiveness of our approach using a real large-scale road network and different traffic simulation scenarios.
- KonferenzbeitragCloudy transactions: cooperative XML authoring on Amazon S3(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Gropengießer, Francis; Baumann, Stephan; Sattler, Kai-UweOver the last few years cloud computing has received great attention in the research community. Customers are entitled to rent infrastructure, storage, and even software in form of services. This way they just have to pay for the actual use of these components or services. Cloud computing also comes with great opportunities for distributed design applications, which often require multiple users to work cooperatively on shared data. In order to enable cooperation, strict consistency is necessary. However, cloud storage services often provide only eventual consistency. In this paper, we propose a system that allows for strict consistent and cooperative XML authoring in distributed environments based on Amazon S3. Our solution makes use of local and distributed transactions, which are synchronized in an optimistic fashion, in order to ensure correctness. An important contribution of this paper is the evaluation of our system in a real deployment scenario upon Amazon S3. We show the strong impact of write operations to S3 on the transaction throughput. Furthermore, we show that fragmenting data increases write performance and reduces storage costs.
- KonferenzbeitragMeasuring energy consumption of a database cluster(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Hudlet, Volker; Schall, DanielEnergy consumption of database servers is a growing concern for companies as it is a critical part of a data center's cost. To address the rising cost and the waste of energy, a new paradigm called GreenIT arose. Hardware and software developers are aiming at more energy-efficient systems. To improve the energy footprint of database servers, we developed a cluster of small-scale nodes, that can be dynamically powered dependent on the workload. This demo shows the measurement framework we set up to measure hardware components as well as an entire cluster of nodes. We'll exhibit the measurement devices for components and servers and show the system's behavior under varying workloads. Attendees will be able to adjust workloads and experience their impact on energy consumption.
- KonferenzbeitragMOAW: an agile visual modeling and exploration tool for irregularly structured data(Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Werner, Horst; Bornhoevd, Christof; Kubis, Robert; Voigt, HannesThe Mother of all Whiteboards (MOAW) is an innovative visual modeling and exploration tool for semi-structured information. It combines gesture-based user interaction with deep zooming, particle dynamics and the powerful data processing capabilities of SAP's newly developed Active Information Store. This application has been designed to convey complex information by easily created visual models which are backed by a formal representation and thus allow the fluid navigation to unlimited levels of detail and creation of different angles of view.