Abstract: Labeling schemes lie at the core of query processing for many XML database management systems. Designing labeling schemes for dynamic XML documents is an important problem that has received a lot of research attention. Existing dynamic labeling schemes, however, often sacrifice query performance and introduce additional labeling cost to facilitate arbitrary updates even when the documents actually seldom get updated. Since the line between static and dynamic XML documents is often blurred in practice, we believe it is important to design a labeling scheme that is compact and efficient regardless of whether the documents are frequently updated or not. In this paper, we propose a novel labeling scheme called DDE (for Dynamic DEwey) which is tailored for both static and dynamic XML documents. For static documents, the labels of DDE are the same as those of dewey which yield compact size and high query performance. When updates take place, DDE can completely avoid re-labeling and its label quality is most resilient to the number and order of insertions compared to the existing approaches. In addition, we introduce Compact DDE (CDDE) which is designed to optimize the performance of DDE for insertions. Both DDE and CDDE can be incorporated into existing systems and applications that are based on dewey labeling scheme with minimum efforts. Experiment results demonstrate the benefits of our proposed labeling schemes over the previous approaches.

Abstract: Active XML is a high-level specification language tailored to data-intensive, distributed, dynamic Web services. Active XML is based on XML documents with embedded function calls. The state of a document evolves depending on the result of internal function calls (local computations) or external ones (interactions with users or other services). Function calls return documents that may be active, and so may activate new subtasks. The focus of this article is on the verification of temporal properties of runs of Active XML systems, specified in a tree-pattern-based temporal logic, Tree-LTL, which allows expressing a rich class of semantic properties of the application. The main results establish the boundary of decidability and the complexity of automatic verification of Tree-LTL properties.

Abstract: Semiconductor device and method for fabricating the same, is disclosed, which can maintain a threshold voltage constant despite of decreased channel width, the device including a first, and a second conductive type wells in a substrate, a first, and a second gate insulating films on the first, and the second conductive type wells, a first gate electrode on the first gate insulating film, the first gate electrode being doped with a second conductive type except for edges of the first gate electrode in a channel width direction counter doped with a first conductive type, a second gate electrode on the second gate insulating film, the second gate electrode being doped with a first conductive type except for edges of the second gate electrode in a channel width direction counter doped with a second conductive type, and isolating regions formed between the first, and second conductive type wells, the first, and second gate insulating films, and the first, and second gate electrodes.

Abstract: The eXtensible Markup Language (XML) has been gaining extraordinary acceptance from many diverse enterprise software companies for their object repositories, data interchange, and development tools. Further, many different domains, organizations and content providers have been publishing and exchanging information via internet by the usage of XML and standard schemas. Efficient implementation of XML in these domains requires well designed XML schemas. In this point of view, design of XML schemas plays an extremely important role in software development process and needs to be quantified for ease of maintainability. In this paper, an attempt has been made to evaluate the quality of XML schema documents (XSD) written in W3C XML Schema language. We propose a metric, which measures the complexity due to the internal architecture of XSD components, and due to recursion. This is the single metric, which cover all major factors responsible for complexity of XSD. The metric has been empirically and theoretically validated, demonstrated with examples and supported by comparison with other well known structure metrics applied on XML schema documents.

Abstract: An apparatus, system, and method are disclosed for efficient content indexing of streaming XML document content A forest generator generates an XML pattern forest from a set of structured index path expressions, the XML pattern forest includes trees and twigs generated from structured index path expressions uniquely associated with a namespace indicator for an XML node The XML node is identified in a stream of at least one XML document A comparison module compares the XML node to nodes of trees and twigs of the XML pattern forest A determination module determines a match between the XML node and an index node in one of a tree and a twig of the XML pattern forest The index node has a path from an ancestor node to the index node that matches the axis steps of at least one of the structured index path expressions A storage module stores an index entry for the XML node in response to the determined match, the index entry includes a XML document identifier, an XML node name, a namespace indicator for the XML node, and XML node content

Abstract: With the rapid emergence of XML as a data exchange and data transfer medium over the Web, querying XML data has become a major concern. Labeling schemes have been developed to optimize query retrieval, since they provide a quick way to determine the type of relationships that are present among the nodes. In this paper, we analyze how each approach works, as well as its advantages and disadvantages. In addition, we discuss some of the current trends in labeling methods, which indicate a clear shift towards hybrid approaches. Hybrid systems open the possibility of balancing one technology’s weakness with another technology’s strengths.

Abstract: The structural heterogeneity and complexity of XML repositories makes query formulation challenging for users who have little knowledge of XML. To assist its users, an XML retrieval system can have a keyword-based interface, relegating the task of combining textual and structural clues to the retrieval algorithm. In this work, we propose an automatic query refinement method to transform a keyword query into structured XML queries that capture the original information need and conform to the underlying XML data. We formulate query generation as a search problem, and show the effectiveness of the method in generating accurate content-and-structure queries.

Abstract: One of the key challenges in a peer-to-peer (P2P) network is to efficiently locate relevant data sources across a large number of participating peers With the increasing popularity of the extensible markup language (XML) as a standard for information interchange on the Internet, XML is commonly used as an underlying data model for P2P applications to deal with the heterogeneity of data and enhance the expressiveness of queries In this paper, we address the problem of efficiently locating relevant XML documents in a P2P network, where a user poses queries in a language such as XPath We have developed a new system called psiX that runs on top of an existing distributed hashing framework Under the psiX system, each XML document is mapped into an algebraic signature that captures the structural summary of the document An XML query pattern is also mapped into a signature The query's signature is used to locate relevant document signatures Our signature scheme supports holistic processing of query patterns without breaking them into multiple path queries and processing them individually The participating peers in the network collectively maintain a collection of distributed hierarchical indexes for the document signatures Value indexes are built to handle numeric and textual values in XML documents These indexes are used to process queries with value predicates Our experimental study on PlanetLab demonstrates that psiX provides an efficient location service in a P2P network for a wide variety of XML documents

Abstract: XML queries are frequently based on path expressions where their elements are connected to each other in a tree-pattern structure, called query tree pattern (QTP). Therefore, a key operation in XML query processing is finding those elements which match the given QTP. In this paper, we propose a novel method, called S^3, which can selectively process the document's nodes. In S^3, unlike all previous methods, path expressions are not directly executed on the XML document, but first they are evaluated against a guidance structure, called QueryGuide. Enriched by information extracted from the QueryGuide, a query execution plan, called SMP, is generated to provide focused pattern matching and avoid document access as far as possible. Moreover, our experimental results confirm that S^3 and its optimized version OS^3 substantially outperform previous QTP processing methods w.r.t. response time, I/O overhead, and memory consumption - critical parameters in any real multi-user environment.

Abstract: The XML Business Reporting Language (XBRL) is a standard for business and financial information reporting. It is based on XML so instance documents based on XBRL, e.g. a quarterly report, are highly constrained by the XML document-oriented nature. This makes more difficult to perform queries that mix information from filings from different dates, companies, or accounting principles than with a formalism based on a graph model instead of a tree model. Semantic Web technologies provide a graph model that facilitates mashing-up different XBRL sources. We have put into practice this approach mapping the XBRL filings available from the SEC’s EDGAR program to Resource Description Framework (RDF) and the XML Schema taxonomies these filings are based on to Web Ontology Language (OWL). The resulting semantic metadata, though highly tied to the XML structure it is mapped from, benefits from Semantic Web technologies and tools in order to facilitate integration and crossquerying, even together with other parts of the Web of Linked Data.

Abstract: The tremendous acceptance of web applications, or more specifically, rich media applications are about to be extended to embedded devices such as mobile phones, digital picture frames or TV sets. The Extensible Markup Language (XML) is one important pillar when we deal with such internet applications. XML is known as the interchange language of the web. Besides its outstanding features, in the domain of embedded devices, XML is difficult to handle due to the processing overhead and the verbosity associated with its use. This paper evaluates the efficient access of rich internet applications especially in the domain of resource limited embedded devices such as digital picture frames. For this purpose, typical XML source information models for rich internet applications, such as Silverlight and SVG, are evaluated. In this context, the new Efficient XML Interchange (EXI) format is applied and studied. Finally a generic adaption of the EXI format is developed to even increase the efficiency. The paper concludes with the proposal for further studies on an integration of EXI-based typed interfaces to reduce the processing complexity for rich media applications on embedded devices.

Abstract: The XML signature wrapping attack is one of the most discussed security issues of the Web Services security community during the last years. Until now, the issue has not been solved, and all countermeasure approaches proposed so far were shown to be insufficient.In this paper, we present yet another way to perform signature wrapping attacks by using the XML namespace injection technique. We show that the interplay of XML Signature, XPath, and the XML namespace concept has severe flaws that can be exploited for an attack, and that XML namespaces in general pose real troubles to digital signatures in the XML domain. Additionally, we present and discuss some new approaches in countering the proposed attack vector.

Abstract: A method and apparatus are provided for building and using a persistent XML tree index for navigating an XML document. The XML tree index is stored separately from the XML document content, and thus is able to optimize performance through the use of fixed-sized index entries. The XML document hierarchy need not be constructed in volatile memory, so creating and using the XML tree index scales even for large documents. To evaluate a path expression including descendent or ancestral syntax, navigation links can be read from persistent storage and used directly to find the nodes specified in the path expression. The use of an abstract navigational interface allows applications to be written that are independent of the storage implementation of the index and the content. Thus, the XML tree index can index documents stored at least in a database, a persistent file system, or as a sequence of in memory.

Abstract: The extensible markup language XML has become the de facto standard for information representation and interchange on the Internet. XML parsing is a core operation performed on an XML document for it to be accessed and manipulated. This operation is known to cause performance bottlenecks in applications and systems that process large volumes of XML data. We believe that parallelism is a natural way to boost performance. Leveraging multicore processors can offer a cost-effective solution, because future multicore processors will support hundreds of cores, and will offer a high degree of parallelism in hardware. We propose a data parallel algorithm called ParDOM for XML DOM parsing, that builds an in-memory tree structure for an XML document. ParDOM has two phases. In the first phase, an XML document is partitioned into chunks and parsed in parallel. In the second phase, partial DOM node tree structures created during the first phase, are linked together (in parallel) to build a complete DOM node tree. ParDOM offers fine-grained parallelism by adopting a flexible chunking scheme --- each chunk can contain an arbitrary number of start and end XML tags that are not necessarily matched. ParDOM can be conveniently implemented using a data parallel programming model that supports map and sort operations. Through empirical evaluation, we show that ParDOM yields better scalability than PXP [23] --- a recently proposed parallel DOM parsing algorithm --- on commodity multicore processors. Furthermore, ParDOM can process a wide-variety of XML datasets with complex structures which PXP fails to parse.

Abstract: Constraints are important for a variety of XML recommendations and applications. Consequently, there are numerous opportunities for advancing the treatment of XML semantics. In particular, suitable notions of keys will enhance XML's capabilities of modeling, managing and processing native XML data. However, the different ways of accessing and comparing XML elements make it challenging to balance expressiveness and tractability.We investigate XML keys which uniquely identify XML elements based on a very general notion of value-equality: isomorphic subtrees with the identity on data values. Previously, an XML key fragment has been recognised that is robust in the sense that its implication problem can be expressed as the reachability problem in a suitable digraph. We analyse the impact of extending this fragment by structural keys that uniquely identify XML elements independently of any data. We establish a sound and complete set of inference rules for this expressive fragment of XML keys, and encode these rules in an algorithm that decides the associated implication problem in time quadratic in the size of the input keys. Consequently, we gain significant expressiveness without any loss of efficiency in comparison to less expressive XML key fragments.

Abstract: In a traditional keyword-search system over XML data, a user composes a keyword query, submits it to the system, and retrieves relevant subtrees. In the case where the user has limited knowledge about the data, often the user feels "left in the dark" when issuing queries, and has to use a try-and-see approach for finding information. In this paper, we study a new information-access paradigm for XML data, called "Inks," in which the system searches on the underlying data "on the fly" as the user types in query keywords. Inks extends existing XML keyword search methods by interactively answering queries. We propose effective indices, early-termination techniques, and efficient search algorithms to achieve a high interactive speed. We have implemented our algorithm, and the experimental results show that our method achieves high search efficiency and result quality.

Abstract: XML has conquered its place as the most used standard for representing Web data. An XML schema may be employed for similar purposes of those from database schemas. There are different languages to write an XML schema, such as DTD and XSD. In this paper, we provide a general view, an X-Ray, on Web-available XSD files by identifying which XSD constructs are more and less frequently used. Furthermore, we provide an evolution perspective, showing results from XSD files collected in 2005 and 2008. Hence, we can also draw some conclusions on what trends seem to exist in XSD usage. The results of such study provide relevant information for developers of XML applications, tools and algorithms in which the schema has a distinguished role.

Abstract: This paper presents a novel approach for mapping an existing object-oriented database into XML and vice versa. The major motivation to carry out this study is the fact that it is necessary to facilitate platform independent exchange of the content of object oriented databases and the need to store XML in a structured database. There are more common features between the object-oriented model and XML and thus the the two-way mapping from object-oriented databases into XML (and vice versa) should be less problematic. To achieve the mapping, what we call the object graph is derived based on characteristics of the schema to be mapped. For object-oriented schema, the object graph simply summarizes and includes all nesting and inheritance links, which are the basics of the object-oriented model. Then, the inheritance is simulated in terms of nesting to get a simulated object graph. This way, everything in a simulated object graph is directly representable in XML format. Finally, we handle the mapping of the actual data from the objectoriented database into corresponding XML document(s). On the other hand, the common features between the object-oriented model and XML make it is more attractive to map from XML into object-oriented database; such mapping preserves database specifics. To achieve the mapping, the object graph is derived based on characteristics of the XML schema; it simply summarizes and includes all complex and simple elements and the links, which are the basics of the XML schema. Then, the links are simulated in terms of nesting to get a simulated object graph. This way, everything in a simulated object graph is directly representable in object-oriented database. Finally, we handle the mapping of the actual data from XML document(s) into the corresponding object-oriented database. Povzetek: Prispevek predstavlja izvirno dvostransko preslikavo med objektnimi podatkovnimi bazami in XML.

Abstract: Efficient XML filtering has been the fundamental technique in recent Web service and XML publish/subscribe applications. In this article, we consider the problem of filtering a streaming XML data efficiently against a large number of branch XPath queries. To improve the performance of XML filtering, branch queries are grouped into similar queries, and the common paths between queries in the same group are identified. After performing structural matching of queries, queries are organized in a way that multiple queries can be evaluated simultaneously in the post-processing phase. In the post-processing phase, join operations are executed in a pipeline fashion, and intermediate join results are shared amongst the queries in the same group. As a result, the total number of join operations performed in the post-processing phase is significantly reduced. In addition, we also present how to efficiently return all matching elements for each matching branch query. Experiments show that our proposal is efficient and scalable compared to previous work.

Abstract: Extensible markup language (XML) has become a standard for persistent storage and data interchange via the Internet due to its openness, self-descriptiveness, and flexibility This article proposes a systematic approach to reverse engineer arbitrary XML documents to their conceptual schema–extended DTD graphs?which is a DTD graph with data semantics The proposed approach not only determines the structure of the XML document, but also derives candidate data semantics from the XML element instances by treating each XML element instance as a record in a table of a relational database One application of the determined data semantics is to verify the linkages among elements Implicit and explicit referential linkages are among XML elements modeled by the parent-children structure and ID/IDREF(S) respectively As a result, an arbitrary XML document can be reverse engineered into its conceptual schema in an extended DTD graph format

Abstract: There is much effort to develop comprehensive support for the storage and querying of XML data in database management systems. The major developers have extended their systems to handle XML data natively. These have the advantage over stand-alone XML database systems that relational and XML data can be queried mutually. Indeed, recent SQL standards specify means to query relational and XML data together (called SQL/XML). These systems also now support XQuery, in addition to SQL. It is thus possible to mix the processing of relational and XML data via either query language. While there has been significant progress in efficient native storage systems for XML, there remain numerous challenges to handle efficiently queries over XML. There are efforts to adapt the strong optimization techniques used for relational ("SQL") queries for XML (and mixed) queries as well. One such technique, the materialized view, has been well studied, and well adopted, over the last decade as an effective technique for optimizing relational queries. Our work extends the use of materialized views for SQL/XML, and could be applied to XQuery. Within IBM DB2 9 (Viper), we implement query rewrite rules that enable the use of materialized views in the evaluation of queries over XML. % (We enable views over queries that employ XMLTable.) To accomplish this, it was necessary to extend the existing query matching and compensation framework in DB2 with new functionality. We consider what types of query rewrites based on XMLTable are possible, and which are feasible. We present a linear-time algorithm to determine the locality (self-containment) of XPath expressions within a schema-unaware environment, which we have implemented. We demonstrate the efficacy of our techniques via an experimental evaluation over a representative suite of SQL/XML queries and materialized views, executed over our DB2 prototype.

Abstract: An aspect of the present invention provides a technique to automatically merge information contained in two or more XML documents in to a single merged XML document. The merging technique is based on a comparison logic that involves comparing XML elements of one of the XML document with elements of the other XML document and this element comparison is based on at least one XML attribute associated with the elements of the XML documents and termed as a merge attribute in the embodiments of the invention. An aspect of the present invention involves parsing the XML documents and providing a list of attributes asscociated with the elements of the XML documents and allowing a user to select one or more attributes as merge attributes. In yet another embodiment the XML:ID-type is selected as the default merge attribute.

Abstract: Much research work has recently focused on the problem of representing historical information in XML. This paper describes a number of temporal XML data models and provides their comparison according to the following properties: time dimension (valid time, transaction time), support of temporal elements and attributes, querying possibilities, association to XML Schema/DTD, and influence on XML syntax. We conclude that the approaches of managing time information using XML mostly do not require changes of current standards.

Abstract: Most of the time information handled by organizations has been collected and processed by computers and transmitted across networks to other computers. How can we protect this information from unauthorized access when it is being transmitted? Encryption provides confidentiality by protecting sensitive information from being read by intruders. In this paper, we present two patterns: a Symmetric Encryption pattern that describes a basic type of algorithms and XML Encryption that describes how to apply symmetric and asymmetric encryption to XML messages.

Abstract: Due to an explosive increase of XML documents, it is imperative to manage XML data in an XML data warehouse. XML warehousing imposes challenges, which are not found in the relational data warehouses. In this paper, we firstly present a framework to build an XML data warehouse schema. For the purpose of scalability due to the increase of data volume, we propose a number of partitioning techniques for multi-version XML data warehouses, including document based partitioning, schema based partitioning, and cascaded (mixed) partitioning model. Finally, we formulate cost models to evaluate various types of queries for an XML data warehouse.