How is the Semantic Web evolving? A dynamic social network perspective

Finding how the Semantic Web has evolved can help understand the status of Semantic Web community and predict the diffusion of the Semantic Web. One of the promising applications of the Semantic Web is the representation of personal profiles using Friend of a Friend (FOAF). A key characteristic of such social networks is their continual change. However, extant analyses of social networks on the Semantic Web are essentially static in that the information about the change of social networks is neglected. To address the limitations, we analyzed the dynamics of a large-scale real-world social network in this paper. Social network ties were extracted from both within and between FOAF documents. The former was based on knows relations between persons, and the latter was based on revision relations. We found that the social network evolves in a speckled fashion, which is highly distributed. The network went through rapid increase in size at an early stage and became stabilized later. By examining the changes of structural properties over time, we identified the evolution patterns of social networks on the Semantic Web and provided evidence for the growth and sustainability of the Semantic Web community.     

Laying the foundations for a World Wide Argument Web

This paper lays theoretical and software foundations for a World Wide Argument Web (WWAW): a large-scale Web of inter-connected arguments posted by individuals to express their opinions in a structured manner. First, we extend the recently proposed Argument Interchange Format (AIF) to express arguments with a structure based on Walton's theory of argumentation schemes. Then, we describe an implementation of this ontology using the RDF Schema Semantic Web-based ontology language, and demonstrate how our ontology enables the representation of networks of arguments on the Semantic Web. Finally, we present a pilot Semantic Web-based system, ArgDF, through which users can create arguments using different argumentation schemes and can query arguments using a Semantic Web query language. Manipulation of existing arguments is also handled in ArgDF: users can attack or support parts of existing arguments, or use existing parts of an argument in the creation of new arguments. ArgDF also enables users to create new argumentation schemes. As such, ArgDF is an open platform not only for representing arguments, but also for building interlinked and dynamic argument networks on the Semantic Web. This initial public-domain tool is intended to seed a variety of future applications for authoring, linking, navigating, searching, and evaluating arguments on the Web.     

Semantic Web computing in industry

The Semantic Web has attracted significant attention during the last decade. On the one hand, many research groups have changed their focus towards Semantic Web research and research funding agencies particularly in Europe have explicitly mentioned Semantic Web in their calls for proposals. On the other hand, industry has also begun to watch developments with interest and a number of large companies have started to experiment with Semantic Web technologies to ascertain if these new technologies can be leveraged to add more value for their customers or internally within the company, while there are already several offers of vendors of Semantic Web solutions on the market. The essence of the Semantic Web is to structure Web-based information to make it more interoperable, machine-readable and thereafter to provide a means to relate various information concepts more easily and in a reusable way. The Semantic Web acts as an additional layer on the top of the Web, and is built around explicit representations of information concepts and their relationships such as ontologies and taxonomies. Furthermore, Semantic Web technologies are not only valuable on an open environment like the Web, but also in closed systems such as in industrial settings. Hence, these technologies can be efficiently deployed for domains including Web Services, Enterprise Application Integration, Knowledge Management and E-Commerce, fulfilling existing gaps in current applications. This paper focuses on this synthesis between Semantic Web technologies and systems problems within industrial applications. There will be a short review of Semantic Web standards, languages and technologies followed by a more detailed review of applications of Semantic Web computing in industry. The paper covers theoretical considerations as well as use cases and experience reports on the topic, and we also present some current challenges and opportunities in the domain.     

Metcalfe's law, Web 2.0, and the Semantic Web

The power of the Web is enhanced through the network effect produced as resources link to each other with the value determined by Metcalfe's law. In Web 2.0 applications, much of that effect is delivered through social linkages realized via social networks online. Unfortunately, the associated semantics for Web 2.0 applications, delivered through tagging, is generally minimally hierarchical and sparsely linked. The Semantic Web suffers from the opposite problem. Semantic information, delivered through ontologies of varying amounts of expressivity, is linked to other terms (within or between resources) creating a link space in the semantic realm. However, the use of the Semantic Web has yet to fully realize the social schemes that provide the network of users. In this article, we discuss putting these together, with linked semantics coupled to linked social networks, to deliver a much greater effect.     

一种基于Agent的语义Web服务编制框架

针对动态、开放网络环境下复杂多变的业务需求,本文在前期语义编程语言SPL研究的基础上,提出一种基于Agent和本体的语义Web服务编制方法,形成一个以语义编程语言SPL为核心的、可适用于将语义Web服务与多A-gent技术无缝集成起来的,进行语义Web服务编制的技术框架。框架实现基于SPL开发和运行支撑平台,该平台为语义Web服务和软件Agent提供必要的运行支持。     

What would it mean to blog on the semantic web?

The phenomenon known as Web logging (“blogging”) has helped realize an initial goal of the Web: to turn Web content consumers (i.e., end users) into Web content producers. As the Semantic Web unfolds, we feel there are two questions worth posing: (1) do blog entries have semantic structure that can be usefully captured and exploited? (2) Is blogging a natural way to encourage growth of the Semantic Web? We explore empirical evidence for answering these questions in the affirmative and propose means to bring blogging into the mainstream of the Semantic Web, including ontologies that extend the RSS 1.0 specification and an XSL transform for handling RSS 0.9x/2.0 files. To demonstrate the validity of our approach we have constructed a semantic blogging environment based on Haystack. We argue that with tools such as Haystack, semantic blogging will be an important paradigm by which metadata authoring will occur in the future.     

Effektive Handhabung von Service-Informationen im Internet der Dienste

Business Webs apply the idea of value networks to the WWW. The underlying delivery platform is commonly referred to as the Internet of Services and will certainly have to deal with a great variety and amount of information about services along several service information dimensions. As soon as brokerage, discovery, or community feedback parts are decentralized, there emerge a number of service information challenges (modeling the information in a holistic way, documentation, interlinkage, tool interoperability, distributed querying, inconsistent information, and cooperation of different stakeholders). In this paper, we propose to counter such service information challenges by two artifacts. First, we contribute a Service Ontology based on a sound and rigid foundational ontology. The Service Ontology provides a holistic and consistent way of capturing service information. We apply the recommendations of the W3C Semantic Web Activity whose recent standardization has already opened new possibilities for tool interoperability, interlinkage of information, and distributed querying on the web. However, building and prescribing an ontology in standardized languages is not enough to address all service information challenges. Therefore, as a second contribution, we provide a method around the ontology including a governance framework, guidelines for applying the W3C Semantic Web recommendations, a lifecycle-spanning tool chain, and different levels of applicability. We label our method Semantic Business Web approach, since we build on W3C Semantic Web standards, use and extend them in the Business Web setting. Both artifacts are constructed in an interdisciplinary way by experts participating in the German lighthouse project THESEUS/TEXO. The project’s scenario also serves as a proof of concept evaluation of the artifacts.     

Relevance feedback between hypertext and Semantic Web search: Frameworks and evaluation

We investigate the possibility of using Semantic Web data to improve hypertext Web search. In particular, we use relevance feedback to create a ‘virtuous cycle’ between data gathered from the Semantic Web of Linked Data and web-pages gathered from the hypertext Web. Previous approaches have generally considered the searching over the Semantic Web and hypertext Web to be entirely disparate, indexing, and searching over different domains. While relevance feedback has traditionally improved information retrieval performance, relevance feedback is normally used to improve rankings over a single data-set. Our novel approach is to use relevance feedback from hypertext Web results to improve Semantic Web search, and results from the Semantic Web to improve the retrieval of hypertext Web data. In both cases, an evaluation is performed based on certain kinds of informational queries (abstract concepts, people, and places) selected from a real-life query log and checked by human judges. We evaluate our work over a wide range of algorithms and options, and show it improves baseline performance on these queries for deployed systems as well, such as the Semantic Web Search engine FALCON-S and Yahoo! Web search. We further show that the use of Semantic Web inference seems to hurt performance, while the pseudo-relevance feedback increases performance in both cases, although not as much as actual relevance feedback. Lastly, our evaluation is the first rigorous ‘Cranfield’ evaluation of Semantic Web search.     

基于本体的语义Web研究

语义Web与本体的关系极为特殊,本体在语义Web本身的体系结构中扮演着极为重要的角色,同时,位于语义Web体系结构的其它层的XML、RDF(S)等与本体也有着千丝万缕的联系。为阐述两者的关系,探讨基于本体的语义Web的特点及应用,介绍了本体和语义Web的产生和发展,在此基础上对基于本体的语义Web进行研究,重点分析了本体在描述语义方面弥补了XML、RDF(S)等的不足,并结合Web服务检索的实例介绍了本体在Web服务上的应用。     

POLYPHONET: An advanced social network extraction system from the Web

Social networks play important roles in the Semantic Web: knowledge management, information retrieval, ubiquitous computing, and so on. We propose a social network extraction system called POLYPHONET, which employs several advanced techniques to extract relations of persons, to detect groups of persons, and to obtain keywords for a person. Search engines, especially Google, are used to measure co-occurrence of information and obtain Web documents.

Several studies have used search engines to extract social networks from the Web, but our research advances the following points: first, we reduce the related methods into simple pseudocodes using Google so that we can build up integrated systems. Second, we develop several new algorithms for social network mining such as those to classify relations into categories, to make extraction scalable, and to obtain and utilize person-to-word relations. Third, every module is implemented in POLYPHONET, which has been used at four academic conferences, each with more than 500 participants. We overview that system. Finally, a novel architecture called Iterative Social Network Mining is proposed. It utilizes simple modules using Google and is characterized by scalability and relate–identify processes: identification of each entity and extraction of relations are repeated to obtain a more precise social network.     

Piggy Bank: Experience the Semantic Web inside your web browser

The Semantic Web Initiative envisions a Web wherein information is offered free of presentation, allowing more effective exchange and mixing across web sites and across web pages. But without substantial Semantic Web content, few tools will be written to consume it; without many such tools, there is little appeal to publish Semantic Web content.To break this chicken-and-egg problem, thus enabling more flexible information access, we have created a web browser extension called Piggy Bank that lets users make use of Semantic Web content within Web content as users browse the Web. Wherever Semantic Web content is not available, Piggy Bank can invoke screenscrapers to re-structure information within web pages into Semantic Web format. Through the use of Semantic Web technologies, Piggy Bank provides direct, immediate benefits to users in their use of the existing Web. Thus, the existence of even just a few Semantic Web-enabled sites or a few scrapers already benefits users. Piggy Bank thereby offers an easy, incremental upgrade path to users without requiring a wholesale adoption of the Semantic Web's vision.To further improve this Semantic Web experience, we have created Semantic Bank, a web server application that lets Piggy Bank users share the Semantic Web information they have collected, enabling collaborative efforts to build sophisticated Semantic Web information repositories through simple, everyday's use of Piggy Bank.     

Using the Semantic Web for linking and reusing data across Web 2.0 communities

Large volumes of content (bookmarks, reviews, videos, etc.) are currently being created on the “Social Web”, i.e. on Web 2.0 community sites, and this content is being annotated and commented upon. The ability to view an individual's entire contribution to the Social Web would be an interesting and valuable service, particularly important as social networks are often being formed through created content and things that people have in common (“object-centred sociality”). SIOC is a Semantic Web research project that aims to describe online communities on the Social Web. This paper describes how SIOC and the Semantic Web can enable linking and reuse scenarios of data from Web 2.0 community sites, and introduces a SIOC Types module to further specify the type of content items and act as a “glue” between user posts and the content items created and annotated by users.     

Ontology-based semantic search on the Web and its combination with the power of inductive reasoning

Semantic Web search is currently one of the hottest research topics in both Web search and the Semantic Web. In previous work, we have presented a novel approach to Semantic Web search, which allows for evaluating ontology-based complex queries that involve reasoning over the Web relative to an underlying background ontology. We have developed the formal model behind this approach, and provided a technique for processing Semantic Web search queries, which consists of an offline ontological inference step and an online reduction to standard Web search. In this paper, we continue this line of research. We further enhance the above approach by the use of inductive rather than deductive reasoning in the offline inference step. This increases the robustness of Semantic Web search, as it adds the important ability to handle inconsistencies, noise, and incompleteness, which are all very likely to occur in distributed and heterogeneous environments such as the Web. The inductive variant also allows to infer new (not logically deducible) knowledge (from training individuals). We report on a prototype implementation of (both the deductive and) the inductive variant of our approach in desktop search, and we provide extensive new experimental results, especially on the running time and the precision and the recall of our new?approach.     

KAoS policy management for semantic Web services

Web Services power through explicit representations of Web resources underlying semantics and the development of an intelligent Web infrastructure that can fully exploit them. Semantic Web languages, such as OWL, extend RDF to let users specify ontologies comprising taxonomies of classes and inference rules. Both people and software agents can effectively use Semantic Web Services.' Agents will increasingly use the combination of semantic markup languages and Semantic Web Services to understand and autonomously manipulate Web content in significant ways. Agents will discover, communicate, and cooperate with other agents and services and-as we' 11 describe -will rely on policy-based management and control mechanisms to ensure respect for human-imposed constraints on agent interaction. Policy-based controls of Semantic Web Services can also help govern interaction with traditional (nonagent) clients.     

OIL: an ontology infrastructure for the Semantic Web

Researchers in artificial intelligence first developed ontologies to facilitate knowledge sharing and reuse. Ontologies play a major role in supporting information exchange across various networks. A prerequisite for such a role is the development of a joint standard for specifying and exchanging ontologies. The authors present OIL, a proposal for such a standard. Ontologies applied to the World Wide Web are creating the Semantic Web.     

Social networks applied

Social networks have interesting properties. They influence our lives enormously without us being aware of the implications they raise. The authors investigate the following areas concerning social networks: how to exploit our unprecedented wealth of data and how we can mine social networks for purposes such as marketing campaigns; social networks as a particular form of influence, i.e.., the way that people agree on terminology and this phenomenon's implications for the way we build ontologies and the Semantic Web; social networks as something we can discover from data; the use of social network information to offer a wealth of new applications such as better recommendations for restaurants, trustworthy email senders, or (maybe) blind dates; investigation of the richness and difficulty of harvesting FOAF (friend-of-a-friend) information; and by looking at how information processing is bound to social context, the resulting ways that network topology's definition determines its outcomes.     

Semantic Web search based on ontological conjunctive queries

Many experts predict that the next huge step forward in Web information technology will be achieved by adding semantics to Web data, and will possibly consist of (some form of) the Semantic Web. In this paper, we present a novel approach to Semantic Web search, called Serene, which allows for a semantic processing of Web search queries, and for evaluating complex Web search queries that involve reasoning over the Web. More specifically, we first add ontological structure and semantics to Web pages, which then allows for both attaching a meaning to Web search queries and Web pages, and for formulating and processing ontology-based complex Web search queries (i.e., conjunctive queries) that involve reasoning over the Web. Here, we assume the existence of an underlying ontology (in a lightweight ontology language) relative to which Web pages are annotated and Web search queries are formulated. Depending on whether we use a general or a specialized ontology, we thus obtain a general or a vertical Semantic Web search interface, respectively. That is, we are actually mapping the Web into an ontological knowledge base, which then allows for Semantic Web search relative to the underlying ontology. The latter is then realized by reduction to standard Web search on standard Web pages and logically completed ontological annotations. That is, standard Web search engines are used as the main inference motor for ontology-based Semantic Web search. We develop the formal model behind this approach and also provide an implementation in desktop search. Furthermore, we report on extensive experiments, including an implemented Semantic Web search on the Internet Movie Database.     

基于语义距离度量模型的语义Web服务匹配排序机制

随着语义Web服务技术研究工作的不断深入,因特网上语义Web服务数量急剧增加。如何快速便捷地定位可用语义Web服务已经成为一个迫切且关键的问题。在语义Web服务匹配技术研究中,其中一个重要的研究主题就是语义Web服务匹配结果的排序机制。本文在综合概括和分析各种关于语义Web服务匹配结果排序机制的基础上,提出了一种基于语义距离度量模型的语义Web服务匹配结果排序机制,利用该排序机制,计算待匹配语义Web服务的语义相似度量,并依据此度量对语义Web服务匹配结果进行排序。该度量模型将语义Web服务引用概念间的语义关系转换成可精确比较的量化度量值,对属于相同语义匹配类型的匹配候选服务也能够分别计算语义距离,区分出相同匹配类型的候选服务与服务请求的匹配程度,从而达到改善用户对语义Web服务的搜索体验的目的。