5650965
L-Tree: A Dynamic Labeling Structure for Ordered XML Data
With the ever growing use of XML as a data representation format, we see an increasing need for robust, high performance XML database systems While most of the recent work focuses on efficient XML query processing, XML databases also need to support efficient updates To speed up query processing, various labeling schemes have been proposed However, the vast majority of these schemes have poor update performance In this paper, we introduce a dynamic labeling structure for XML data: L-Tree and its order-preserving labeling scheme with O(log n) amortized update cost and O(log n) bits per label L-Tree has good performance on updates without compromising the performance of query processing We present the update algorithm for L-Tree and analyze its complexity.
365943
Modeling and Storing Scientific Protocols
We propose an abstract model for scientific protocols, where several atomic operators are proposed for protocol composition We distinguish two different layers associated with scientific protocols: design and implementation, and discuss the mapping between them We illustrate our approach with a representative example and describe ProtocolDB, a scientific protocol repository currently in development Our approach benefits scientists by allowing the archiving of scientific protocols with the collected data sets to constitute a scientific portfolio for the laboratory to query, compare and revise protocols.
1747046
UCSOA: User-Centric Service-Oriented Architecture
This paper introduces a new user-centric service-oriented architecture (UCSOA) that allows end users to compose applications. UCSOA is an extension of consumer-centric service-oriented architecture (CCSOA), which is an extension of conventional SOA. The conventional SOA is producer-centric because service providers publish their services and service consumers must search available services to compose their applications. CCSOA is different as it allows consumers publish their needs including workflows and services, and let producers to produce services to meet the requirements. Based on CCSOA, UCSOA provides support for end users. An application builder is an engineer who has both domain and programming knowledge, while an end user has little knowledge on programming and thus UCSOA needs to allow nontechnical persons to compose their applications. This paper presents the concepts, architecture, enabling techniques, and illustrative examples
129842
BLAS: an efficient XPath processing system
We present BLAS, a Bi-LAbeling based System, for efficiently processing complex XPath queries over XML data. BLAS uses P-labeling to process queries involving consecutive child axes, and D-labeling to process queries involving descendant axes traversal. The XML data is stored in labeled form, and indexed to optimize descendent axis traversals. Three algorithms are presented for translating complex XPath queries to SQL expressions, and two alternate query engines are provided. Experimental results demonstrate that the BLAS system has a substantial performance improvement compared to traditional XPath processing using D-labeling.
2771147
Autonomous hot patching for Web-based applications
Patching technologies are commonly applied to improve the dependability of software after release. This paper proposes an autonomous hot patching (AHP) framework to fully automate the reasoning for the causes of failures, and to patch the binary code of Web-based applications. AHP admits the hardness for rooting out all faults before product release, and autonomously patches problems of application programs. By directly operating on binary code, AHP is universal to virtually all applications. A promising application of AHP is to shortcut the remote maintenance center (RMC) and hence to reduce the turn around time for patches.
5453537
Testability of Software in Service-Oriented Architecture
Service-oriented architecture (SOA) is a system architecture in which a collection of loosely coupled services communicate with each other using standard interfaces and message-exchanging protocols. As an emerging technology in software development, the SOA presents a new paradigm, and it affects the entire software development cycle including analysis, specification, design, implementation, verification, validation, maintenance and evaluation. This paper proposes several testability evaluation criteria for SOA software, which serves as a reference for both service providers and application builders to evaluate the test support to SOA software. The proposed evaluation criteria are illustrated in a stock-trading case study
20308502
Object signatures for supporting efficient navigation in object-oriented databases
Most methods that have been proposed to improve query processing in object-oriented databases are designed for the aggregation hierarchy. Although the structure of the generalization hierarchy is similar to the aggregation hierarchy, techniques developed for the aggregation hierarchy cannot fully use the characteristics of the generalization hierarchy to improve performance. We devise a new object signature for the generalization hierarchy. The object signature consists of two parts: a reference signature and a structure signature. The former can be used to eliminate objects that do not match the nested predicates specified in the query, and the latter can be used to eliminate objects that do not belong to the target classes. We propose some processing methods using the object signatures for queries that involve generalization hierarchies. In addition, we define cost models of the object signature and then compare the performance of the traditional query processing method with the object signature method. The results show that using the object signatures can effectively reduce the number of disk accesses in a query.
28422069
Exploration of Coreference Resolution: The ACE Entity Detection and Recognition Task
In this paper, we consider the coreference resolution problem in the context of information extraction as envisioned by the DARPA Automatic Content Extraction (ACE) program Given a set of entity mentions referring to real world entities and a similarity matrix that characterizes how similar those mentions are, we seek a set of entities that are uniquely co-referred to by those entity mentions The quality of the clustering of entity mentions into unique entities significantly depends on the quality of (1) the similarity matrix and (2) the clustering algorithm We explore the coreference resolution problem along those two dimensions and clearly show the tradeoff among several ways of learning similarity matrix and using it while performing clustering.
31504377
Mapping DTDs to object-oriented schemas
As a subset of SGML, XML (Extensible Markup Language) is becoming a dominant standard for representing data in the World Wide Web and therefore the efficient treatment of XML data is important for information transfer over a network. One way towards this goal is to integrate database technology into document management and bring the very nature of database systems into this area, such as query processing, efficient management of secondary storage, version and update control, etc. We propose a new method to map DTDs (Document Type Definition) into object-oriented schemas. In this way, any complicated DTD structure can be treated uniformly. That is, using the concepts of classification/generalization and aggregation of the object-oriented model, any complex nested and recursive structure in a DTD as well as multiple appearance of element types can be represented. These issues can not be addressed if we map a DTD into a relational schema.
2306448
The TheaterLoc Virtual Application
Although much has been written about various information integration technologies, little has been said regarding how to combine these technologies together to build an entire “virtual” application. In this paper, we describe the design and implementation of TheaterLoc, an information integration application that allows users to retrieve information about theaters and restaurants for a variety of cities in the United States, including an interactive map depicting their relative locations and video trailers of the movies playing at the selected theaters. The data retrieved by TheaterLoc comes from five distinct heterogeneous and distributed sources. The enabling technology used to achieve the integration includes the Ariadne information mediator and wrappers for each of the web-based data sources. We focus in detail on the mediator technologies, such as data modeling, source axiom compilation, and query planning. We also describe how the wrappers present an interface for querying data on web sites, aiding in information retrieval used during data integration. Finally, we discuss some of the major integration challenges we encountered and our plans to address them.
3166137
Integrating Temporal Logics
In this paper, we study the predicative semantics of different temporal logics and the relationships between them. We use a notation called generic composition to simplify the manipulation of predicates. The modalities of possibility and necessity become generic composition and its inverse of converse respectively. The relationships between different temporal logics are also characterised as such modalities. Formal reasoning is carried out at the level of predicative semantics and supported by the higher-level laws of generic composition and its inverse. Various temporal domains are unified under a notion called resource cumulation. Temporal logics based on these temporal domains can be readily defined, and their axioms identified. The formalism provides a framework in which human experience about system development can be formalised as refinement laws. The approach is demonstrated in the transformation from Duration Calculus to Temporal Logic of Actions. A number of common design patterns are studied. The refinement laws identified are then applied to the case study of water pump controlling.