This paper faces the problem of the limited availability of datasets for Aspect-Based Sentiment Analysis (ABSA) in the Cultural Heritage domain. Currently, the main datasets for ABSA are product or restaurant reviews. We expand this to book reviews. Our methodology employs an LLM to maintain domain relevance while preserving the linguistic authenticity and natural variations found in genuine reviews. Entity types are annotated through the tool Text2AMR2FRED and evaluated manually. Additionally, we finetuned Llama 3.1 8B as a baseline model that not only performs ABSA, but also performs Entity Typing (ET) with a set of classes from DOLCE foundational ontology, enabling precise categorization of target aspects within book reviews. We present three key contributions as a step forward expanding ABSA: 1) a semi-synthetic set of book reviews, 2) an evaluation of Llama-3-1-Instruct 8B on the ABSA task, and 3) a fine-tuned version of Llama-3-1-Instruct 8B for ABSA.

In recent years, anonymity on the internet has come under intense scrutiny for enabling criminal behaviors like cyberbullying, disinformation, child exploitation, and illicit financial activities. Nevertheless, strong advocates highlight its importance as a protective space for legitimate and ethical actions that individuals may prefer to keep separate from their real-world identities. This paper presents a protocol for authenticated anonymity, enabling anonymous usage that remains unlinkable to real identities unless criminal activity is detected. Blockchain offers a robust and secure framework to manage these needs. While existing solutions — e.g., self-sovereign identities — grant users full control over their disclosure, they lack proper accountability. To address this limitation, the proposed protocol employs a blockchain-driven mechanism that supports anonymous yet verifiable identities. De-anonymization is achieved exclusively through multi-party consensus on the blockchain, t riggered by explicit and non-repudiable requests. We provide the formal mathematical model of the protocol and offer some evaluations of its robustness and fault tolerance, even under large-scale identity management scenarios.

Abstract In this paper we introduce a new class of software tools engaged in delivering successful explanations of complex processes on top of basic Explainable AI (XAI) software systems. These tools, that we call cumulatively Explanatory AI (YAI) systems, enhance the quality of the basic output of a XAI by adopting a user-centred approach to explanation that can cater to the individual needs of the explainees with measurable improvements in usability. Our approach is based on Achinstein’s theory of explanations, where explaining is an illocutionary (i.e., broad yet pertinent and deliberate) act of pragmatically answering a question. Accordingly, user-centrality enters in the equation by considering that the overall amount of information generated by answering all questions can rapidly become overwhelming and that individual users may perceive the need to explore just a few of them. In this paper, we give the theoretical foundations of YAI, formally defining a user-centred explanatory tool and the space of all possible explanations, or explanatory space, generated by it. To this end, we frame the explanatory space as an hypergraph of knowledge and we identify a set of heuristics and properties that can help approximating a decomposition of it into a tree-like representation for efficient and user-centred explanation retrieval. Finally, we provide some old and new empirical results to support our theory, showing that explanations are more than textual or visual presentations of the sole information provided by a XAI.

Many standards and guidelines have been proposed over the years to help web developers produce accessible content. Being designed to be suitable for application to the widest possible number of web technologies, such guidelines are often perceived as hard to understand, not suitable for practical problem solving, and under some circumstances even not really useful in order to develop an accessible website or application.As a consequence, many accompanying resources have been proposed to support developers in understanding accessibility guidelines and applying them to their projects, as well as a variety of testing tools to let them check the presence of accessibility issues in their code and provide guidance in fixing them. Yet, most web content available on the Inter.net still exhibit critical accessibility issues.In our opinion, this approach is non satisfactory, as the personal understanding of the developers is always mediated by written reports and indirect information that are not immediately understandable and actionable. In this paper we propose our approach to increase integration between development tools and accessibility testing tools in usual web development workflows. In particular they should be capable of mapping accessibility related concepts onto familiar and immediately perceivable information, so that developers can immediately pin ìssues and plan for solving them without lengthy and wordy reports.

Explainable AI was born as a pathway to allow humans to explore and understand the inner working of complex systems. Though, establishing what is an explanation and objectively evaluating explainability, are not trivial tasks. With this paper, we present a new model-agnostic metric to measure the Degree of Explainability of (correct) information in an objective way, exploiting a specific theoretical model from Ordinary Language Philosophy called the Achinstein’s Theory of Explanations, implemented with an algorithm relying on deep language models for knowledge graph extraction and information retrieval. In order to understand whether this metric is actually behaving as explainability is expected to, we have devised an experiment on two realistic Explainable AI-based systems for healthcare and finance, using famous AI technology including Artificial Neural Networks and TreeSHAP. The results we obtained suggest that our proposed metric for measuring the Degree of Explainability is robust on several scenarios.

We propose a new method for generating explanations with Artificial Intelligence (AI) and a tool to test its expressive power within a user interface. In order to bridge the gap between philosophy and human-computer interfaces, we show a new approach for the generation of interactive explanations based on a sophisticated pipeline of AI algorithms for structuring natural language documents into knowledge graphs, answering questions effectively and satisfactorily. With this work, we aim to prove that the philosophical theory of explanations presented by Achinstein can be actually adapted for being implemented into a concrete software application, as an interactive and illocutionary process of answering questions. Specifically, our contribution is an approach to frame illocution in a computer-friendly way, to achieve user-centrality with statistical question answering. Indeed, we frame the illocution of an explanatory process as that mechanism responsible for anticipating the needs of the explainee in the form of unposed, implicit, archetypal questions, hence improving the user-centrality of the underlying explanatory process. Therefore, we hypothesise that if an explanatory process is an illocutionary act of providing content-giving answers to questions, and illocution is as we defined it, the more explicit and implicit questions can be answered by an explanatory tool, the more usable (as per ISO 9241-210) its explanations. We tested our hypothesis with a user-study involving more than 60 participants, on two XAI-based systems, one for credit approval (finance) and one for heart disease prediction (healthcare). The results showed that increasing the illocutionary power of an explanatory tool can produce statistically significant improvements (hence with a P value lower than .05) on effectiveness. This, combined with a visible alignment between the increments in effectiveness and satisfaction, suggests that our understanding of illocution can be correct, giving evidence in favour of our theory.

Standards, rules and principles that offer useful recommendations for producing accessible content do exist, but conformance is often not adequately enforced by actual implementations. It is fairly frequent for content authors to produce material that ends up not being accessible without them even noticing it, even when using specialized tools and services. In addition to a well-known scarcity of awareness and even interest, an important reason for this is the difficulty of evaluating and perceiving, for non disabled designers and developers, the impact of accessibility issues on people with disabilities, and existing tools do little or nothing to reduce this “handicap”. Under these assumptions, we plan to work on a new approach based on declarative markup to improve the design and evaluation of accessible content and services. In particular, our strategy encompasses the combined usage of a declarative framework of accessible web components, (to significantly reduce the efforts and knowledge required to produce accessible content), automated accessibility testing tools (tightly integrated in the traditional development workflows), and innovative direct testing tools that let non-disabled people represent accessibility issues in their works as perceptions in ways they are more familiar with. We argue that, in contrast with the more traditional approach to web accessibility based on highly specialized competency and reliance on external tools, our approach has the potential to make accessibility more accessible for development teams that neither have the necessary knowledge to produce accessible content and implement accessible services, nor can afford the cost to acquire them from the outside.

International Private Law (PIL) is a complex legal domain that presents frequent conflicting norms between the hierarchy of legal sources, legal domains, and the adopted procedures. Scientific research on PIL reveals the need to create a bridge between European and national laws. In this context, legal experts have to access heterogeneous sources, being able to recall all the norms and to combine them using case-laws and following the principles of interpretation theory. This clearly poses a daunting challenge to humans, whenever Regulations change frequently or are big-enough in size. Automated reasoning over legal texts is not a trivial task, because legal language is very specific and in many ways different from a commonly used natural language. When applying state-of-the-art language models to legalese understanding, one of the challenges is always to figure how to optimally use the available amount of data. This makes hard to apply state-of-the-art sub-symbolic question answering algorithms on legislative texts, especially the PIL ones, because of data scarcity. In this paper we try to expand previous works on legal question answering, publishing a larger and more curated dataset for the evaluation of automated question answering on PIL.

We propose a new method for explanations in Artificial Intelligence (AI) and a tool to test its expressive power within a user interface. In order to bridge the gap between philosophy and human-computer interfaces, we show a new approach for the generation of interactive explanations based on a sophisticated pipeline of AI algorithms for structuring natural language documents into knowledge graphs, answering questions effectively and satisfactorily. Among the mainstream philosophical theories of explanation we identified one that in our view is more easily applicable as a practical model for user-centric tools: Achinstein’s Theory of Explanation. With this work we aim to prove that the theory proposed by Achinstein can be actually adapted for being implemented into a concrete software application, as an interactive process answering questions. To this end we found a way to handle the generic (archetypal) questions that implicitly characterise an explanatory processes as preliminary overviews rather than as answers to explicit questions, as commonly understood. To show the expressive power of this approach we designed and implemented a pipeline of AI algorithms for the generation of interactive explanations under the form of overviews, focusing on this aspect of explanations rather than on existing interfaces and presentation logic layers for question answering. Accordingly, through the identification of a minimal set of archetypal questions it is possible to create a generator of explanatory overviews that is generic enough to significantly ease the acquisition of knowledge by humans, regardless of the specificities of the users outside of a minimum set of very broad requirements (e.g. people able to read and understand English and capable of performing basic common-sense reasoning). We tested our hypothesis on a well-known XAI-powered credit approval system by IBM, comparing CEM, a static explanatory tool for post-hoc explanations, with an extension we developed adding interactive explanations based on our model. The results of the user study, involving more than 100 participants, showed that our proposed solution produced a statistically relevant improvement on effectiveness (U=931.0, p=0.036) over the baseline, thus giving evidence in favour of our theory.

This paper presents an AI use-case developed in the project “Study on legislation in the era of artificial intelligence and digitization” promoted by the EU Commission Directorate-General for Informatics. We propose a hybrid technical framework where AI techniques, Data Analytics, Semantic Web approaches and LegalXML modelisation produce benefits in legal drafting activity. This paper aims to classify the corrigenda of the EU legislation with the goal to detect some criteria that could prevent errors during the drafting or during the publication process. We use a pipeline of different techniques combining AI, NLP, Data Analytics, Semantic annotation and LegalXML instruments for enriching the non-symbolic AI tools with legal knowledge interpretation to offer to the legal experts.

This study discusses the interplay between metrics used to measure the explainability of the AI systems and the proposed EU Artificial Intelligence Act. A standardisation process is ongoing: several entities (e.g. ISO) and scholars are discussing how to design systems that are compliant with the forthcoming Act and explainability metrics play a significant role. This study identifies the requirements that such a metric should possess to ease compliance with the AI Act. It does so according to an interdisciplinary approach, i.e. by departing from the philosophical concept of explainability and discussing some metrics proposed by scholars and standardisation entities through the lenses of the explainability obligations set by the proposed AI Act. Our analysis proposes that metrics to measure the kind of explainability endorsed by the proposed AI Act shall be risk-focused, model-agnostic, goal-aware, intelligible & accessible. This is why we discuss the extent to which these requirements are met by the metrics currently under discussion.

This paper presents the Open Knowledge Extraction (OKE) tools combined with natural language analysis of the sentence in order to enrich the semantic of the legal knowledge extracted from legal text. In particular the use case is on international private law with specific regard to the Rome I Regulation EC 593/2008, Rome II Regulation EC 864/2007, and Brussels I bis Regulation EU 1215/2012. A Knowledge Graph (KG) is built using OKE and Natural Language Processing (NLP) methods jointly with the main ontology design patterns defined for the legal domain (e.g., event, time, role, agent, right, obligations, jurisdiction). Using critical questions, underlined by legal experts in the domain, we have built a question answering tool capable to support the information retrieval and to answer to these queries. The system should help the legal expert to retrieve the relevant legal information connected with topics, concepts, entities, normative references in order to integrate his/her searching activities.

The way humans and algorithms look at and understand differences between versions and variants of the same text may be very different. While correctness and overall byte length are fundamental aspects of good outputs of diff algorithms, they do not usually provide immediately interesting values for humans trying to make sense of the events that lead from one version to another of a text.

There are several domains in which the documents are made of reusable pieces. Template languages have been widely studied by the document engineering community to deal with common structures and textual fragments. Though, templating mechanisms are often hidden in mainstream word-precessors and even unknown by common users.

Recently, several proposals and discussions have tried to push the use of HTML for preparing and sharing research works within the scholarly domain. Therefore, several native HTML-based templates and formats have been introduced for allowing researchers to write scientific documents, which could be access even with assistive technologies, e.g., screen readers. While HTML can be a good basis for guaranteeing accessibility of such papers, several issues are still in place when we consider the inclusion of non-textual entities in the main text, such as complex formulas and figures. In this paper we experiment on the use of one of such HTML formats, i.e., the Research Articles in Simplified HTML (RASH) format, extended for creating accessible graphs automatically out of CSV data. In particular, we introduce an extension to RASH to let the creation of accessible graphs. Moreover, we analyze the outcomes of some preliminary experiments we have done by using different screen readers on several operating systems and browsers.

The most used format for submitting and publishing papers in the academic domain is the Portable Document Format (PDF), since its possibility of being rendered in the same way independently from the device used for visualising it. However, the PDF format has some important issues as well, among which the lack of interactivity and the low degree of accessibility. In order to address these issues, recently some journals, conferences, and workshops have started to accept also HTML as Web-first submission/publication format. However, most of the people are not able to produce a well-formed HTML5 article from scratch, and they would, thus, need an appropriate interface, e.g. a word processor, for creating such HTML-compliant scholarly article. To provide a solution to the aforementioned issue, in this paper we introduce the RASH JavaScript Editor (a.k.a. RAJE), which is a multi platform word processor for writing scholarly articles in HTML natively. RAJE allows authors to write research papers by means of a user-friendly interface hiding the complexities of HTML5. We also discuss the outcomes of a user study where we asked some researchers to write a scientific paper using RAJE.

Akoma Ntoso is an OASIS Committee Specification Draft standard for the electronic representations of parliamentary, normative and judicial documents in XML. Recently, it has been officially adopted by the United Nations (UN) as the main electronic format for making UN documents machine-processable. However, Akoma Ntoso does not force nor define any formal ontology for allowing the description of real-world objects, concepts and relations mentioned in documents. In order to address this gap, in this paper we introduce the United Nations System Document Ontology (UNDO), i.e. an OWL 2 DL ontology developed and adopted by the United Nations that aims at providing a framework for the formal description of all these entities.

Summary There are two main approaches to manage changes in XML documents, change‐tracking and diff. Change‐tracking tools, which record edit actions while they are performed on the source document, are able to capture the exact editing process. That is much more difficult for diff algorithms, which have to reconstruct it by comparing two different versions. Interestingly, these algorithms process both text‐centric and data‐centric XML documents the same way. In this paper, we show that more accurate, clear, and human‐readable results can be achieved on text‐centric resources, by employing specific models and algorithms. We describe and discuss a specialized diff algorithm for such a class of documents. We also compare a Java implementation of the algorithm, named JNDiff, with other general‐purpose or data‐oriented diff tools, focusing on the quality of their output. Copyright © 2014 Copyright © 2014 John Wiley & Sons, Ltd.

Bibliographies are fundamental components of academic papers and both the scientific research and its evaluation are fundamentally organized around the correct examination and classification of scientific bibliographies. Currently, most digital libraries publish bibliographic information about their content for free, and many include the citations (outgoing and in some cases even incoming) to the papers they manage. Unfortunately no sophistication is spent for these lists: monolithic pieces of text where it is even difficult to tell automatically the authors, the title and publication details, and where users are provided with no mechanisms to filter and access full context of each citation. For instance, there is no way to know in which sentence a work was cited (the citation context) and why (the citation function).

We present a REST approach to build Health services on the Web. Our proposal originates by the necessity of evolving the current regional health service to accommodate emerging needs that are too complex to accomplish with the current system. The original system extends on the regional scale of Emilia-Romagna, and it is one of the most advanced in Italy. Our architecture inherits some of the basic Web methodologies and techniques to implement an highly scalable and flexible system that is capable to satisfy the current needs and their planned evolutions. Moreover, our approach should allow for an effortlessly addressing of future requirements not foreseen at the moment. Without revolutionizing the current IT infrastructure, our approach introduces a new paradigm that could be implemented by a sophisticated interface to access data and resources.

This paper presents the application of the Akoma Ntoso XML standard to the Swiss Federal Chancellery, in particular to the Official Publications Centre document workflow in relation of the IRIs/URIs naming convention. A robust proof-of-concept was conducted on a variety of document types and a IRIs/URIs resolver was implemented for managing the dereferencing to the official sources.

Evaluating collections of XML documents without paying attention to the schema they were written in may give interesting insights into the expected characteristics of a markup language, as well as any regularity that may span vocabularies and languages, and that are more fundamental and frequent than plain content models. In this paper we explore the idea of structural patterns in XML vocabularies, by examining the characteristics of elements as they are used, rather than as they are defined. We introduce from the ground up a formal theory of 8 plus 3 structural patterns for XML elements, and verify their identifiability in a number of different XML vocabularies. The results allowed the creation of visualization and content extraction tools that are completely independent of the schema and without any previous knowledge of the semantics and organization of the XML vocabulary of the documents.

Recognising textual structures (paragraphs, sections, etc.) provides abstract and more general mechanisms for describing documents independent of the particular semantics of specific markup schemas, tools and presentation stylesheets. In this paper we propose an algorithm that allows us to identify the structural role of each element in a set of homogeneous scientific articles stored as XML files.

We present here the workshop DH-CASE 2013, aimed at investigating the state of art in the field of collaboration in text annotation, by exploring methods, tools and techniques used in the domain of the Digital Humanities (DH).

This paper presents ALLOT, an ontology based on Akoma Ntoso to describe entities referenced in legal documents. The focus is on the use of ALLOT to bridge heterogeneous knowledge bases. We present some experiments in integrating heterogeneous legal datasets through ALLOT. We also discuss the lessons learned in the development of this ontology, lessons that can highlight some issues with the current landscape of legal formats and data.

Ontologies are knowledge constructs essential for creation of the Web of Data. Good documentation is required to permit people to understand ontologies and thus employ them correctly, but this is costly to create by tradition authorship methods, and is thus inefficient to create in this way until an ontology has matured into a stable structure. The authors describe three tools, LODE, Parrot and the OWLDoc-based Ontology Browser, that can be used automatically to create documentation from a well-formed OWL ontology at any stage of its development. They contrast their properties and then report on the authors’ evaluation of their effectiveness and usability, determined by two task-based user testing sessions.

XML is among the preferred formats for storing the structure of documents such as scientific articles, manuals, documentation, literary works, etc. Sometimes publishers adopt established and well-known vocabularies such as DocBook and TEI, other times they create partially or entirely new ones that better deal with the particular requirements of their documents. The (explicit and implicit) requirements of use in these vocabularies often follow well-established patterns, creating meta-structures (the block, the container, the inline element, etc.) that persist across vocabularies and authors and that describe a truer and more general conceptualization of the documents' building blocks. Addressing such meta-structures not only gives a better insight of what documents really are composed of, but provides abstract and more general mechanisms to work on documents regardless of the availability of specific schemas, tools and presentation stylesheets. In this paper we introduce a schemaindependent theory based on eleven structural patterns. We provide a definition of such patterns and how they synthesize characteristics emerging from real markup documents. Additionally, we propose an algorithm that allows us to identify the pattern of each element in a set of homogeneous markup documents.

The semantic enhancement of a traditional scientific paper is not a straightforward operation, since it involves many different aspects or facets. In this paper we propose eight different semantic lenses through which these facets may be viewed, and describe and exemplify the ontologies by which these lenses may be implemented.

SUMMARY The problem of line breaking consists of finding the best way to split paragraphs into lines. It has been cleverly addressed by the total‐fit algorithm exposed by Knuth and Plass in a well‐known paper. Similarly, page‐breaking algorithms break the content flow of a document into page units. Formatting languages—such as the World Wide Web Consortium standard Extensible Stylesheet Language Formatting Objects (XSL‐FO)—allow users to set which content should be kept in the same page and how many isolated lines are acceptable at the beginning/end of each page. The strategies most formatters adopt to meet these requirements, however, are not satisfactory for many publishing contexts as they very often generate unpleasant empty areas. In that case, typographers are required to manually craft the results in order to completely fill pages. This paper presents a page‐breaking algorithm that extends the original Knuth and Plass line‐breaking approach and produces high‐quality documents without unwanted empty areas. The basic idea consists of delaying the definitive choice of breaks in the line‐breaking process in order to provide a larger set of alternatives to the actual pagination step. The algorithm also allows users to decide the set of properties to be adjusted for pagination and their variation ranges. An application of the algorithm to XSL‐FO is also presented, with an extension of the language that allows users to drive the pagination process. The tool, named FOP+, is a customized version of the open‐source Apache Formatting Objects Processor formatter. Copyright © 2011 John Wiley & Sons, Ltd.

Overlapping structures in XML are not symptoms of a misunderstanding of the intrinsic characteristics of a text document nor evidence of extreme scholarly requirements far beyond those needed by the most common XML-based applications. On the contrary, overlaps have started to appear in a large number of incredibly popular applications hidden under the guise of syntactical tricks to the basic hierarchy of the XML data format. Unfortunately, syntactical tricks have the drawback that the affected structures require complicated workarounds to support even the simplest query or usage. In this article, we present Extremely Annotational Resource Description Framework (RDF) Markup (EARMARK), an approach to overlapping markup that simplifies and streamlines the management of multiple hierarchies on the same content, and provides an approach to sophisticated queries and usages over such structures without the need of ad-hoc applications, simply by using Semantic Web tools and languages. We compare how relevant tasks (e.g., the identification of the contribution of an author in a word processor document) are of some substantial complexity when using the original data format and become more or less trivial when using EARMARK. We finally evaluate positively the memory and disk requirements of EARMARK documents in comparison to Open Office and Microsoft Word XML-based formats.

In this paper we propose a novel approach to markup, called Extreme Annotational RDF Markup (EARMARK), using RDF and OWL to annotate features in text content that cannot be mapped with usual markup languages. EARMARK provides a unifying framework to handle tree-based XML features as well as more complex markup for non-XML scenarios such as overlapping elements, repeated and non-contiguous ranges and structured attributes. EARMARK includes and expands the principles of XML markup, RDFa inline annotations and existing approaches to overlapping markup such as LMNL and TexMecs. EARMARK documents can also be linearized into plain XML by choosing any of a number of strategies to express a tree-based subset of the annotations as an XML structure and fitting in the remaining annotations through a number of "tricks", markup expedients for hierarchical linearization of non-hierarchical features. EARMARK provides a solid platform for providing vocabulary-independent declarative support to advanced document features such as transclusion, overlapping and out-of-order annotations within a conceptually insensitive environment such as XML, and does so by exploiting recent semantic web concepts and languages.

This paper presents a legal metadata interchange framework for adding semantics on top of the CEN Metalex standard. Indeed for exploiting its potentialities CEN Metalex needs to be enriched with a legal document ontology and moreover to an intermediate layer called LMIF for managing in automatic way the mapping between different local metadata on the general structural layer.

Semantic search engines rely on the existence of a rich set of semantic connections between the concepts associated to documents and those used for the queries. With folksonomies, this is not always guaranteed. Creating clusters of folksonomic tags around terms of controlled ontological vocabularies is a potentially sophisticated approach, but algorithms abound for this clustering and no clear cut winner exists. In this paper we introduce FolksEngine, a parametric search engine for folksonomies allowing to specify any clustering algorithm as a three step process: the user’s query is expanded according to semantic rules associated to the terms of the query, the new query is then executed on the plain folksonomy search engine, and the results are ranked according to semantic rules associated to the folksonomic tags actually used for the documents.

Validation of XML documents is required in order to maintain consistency in large XML document bases, including document bases of legal texts such as acts, judgments, hansards. Current W3C standards for XML validation either do not provide enough precision (DTD) or are too complex to be immediately authored and read by humans (XML Schema). DTD++ has been proposed as an alternative, and relevant legal standards such as Norme In Rete (Italy), Akoma Ntoso (UN for Africa) and CEN Metalex (European CEN standard) are first written in DTD++ and then converted for standard purposes into XML schema and/or DTD. XDTD is a followup of DTD++, and is a shorter and simplified syntax for XML Schema. XDTD combines the power of the XML Schema model with the readability of DTD. The whole set of features of the XML Schema language, including the new ones in the forthcoming 1.1 version of the language, is available in XDTD, while maintaining the same readability and compactness of the original DTD language. In this paper we show how XDTD simplifies the compilation of vocabularies, with attention to legal standards such as the Akoma Ntoso, Norme In Rete and CEN Metalex legal standards.

Existing layout languages provide support for geometric properties allowing - and in a sense forcing - users to give a complete geometric description of the desired output: if the characteristics of the output medium change, the layout of the whole document has to be reworked completely, as the properties set by the user are no longer appropriate for the modified context.

Technical challenges for non-experts in creating content for e-learning are not trivial. Many more issues raise when that content is required to be universal, usable and accessible. The high-quality of the output, however, seems to be still indissoluble from the high-complexity of the authoring processes. This paper proposes a novel approach to lighten the burden to authors, and to make them produce sophisticated learning objects with little effort. We also describe ISA-WebLob, an authoring platform which takes that approach to implementation.

Wiki content templating enables reuse of content structures among wiki pages. In this paper we present a thorough study of this widespread feature, showing how its two state of the art models (functional and creational templating) are sub-optimal. We then propose a third, better, model called lightly constrained (LC) templating and show its implementation in the Moin wiki engine. We also show how LC templating implementations are the appropriate technologies to push forward semantically rich web pages on the lines of (lowercase) semantic web and microformats.

In the past few years, a number of constraint languages for XML documents has been proposed. They are cumulatively called schema languages or validation languages and they comprise, among others, DTD, XML Schema, RELAX NG, Schematron, DSD, xlinkit. One major point of discrimination among schema languages is the support of co-constraints, or co-occurrence constraints, e.g., requiring that attribute A is present if and only if attribute B is (or is not) presentin the same element. Although there is no way in XML Schema to express these requirements, they are in fact frequently used in many XML document types, usually only expressed in plain human-readable text, and validated by means of special code modules by the relevant applications. In this paper we propose SchemaPath, a light extension of XML Schema to handle conditional constraints on XML documents. Two new constructs have been added to XML Schema: conditions -- based on XPath patterns -- on type assignments for elements and attributes; and a new simple type, xsd:error, for the direct expression of negative constraints (e.g. it is prohibited for attribute A to be present if attribute B is also present). A proof-of-concept implementation is provided. A Web interface is publicly accessible for experiments and assessments of the real expressiveness of the proposed extension.

In the linking model of the World Wide Web each link is stored in the referring document within an attribute of the A tag. All the hyperlink defined this way can reference a single resource or a single fragment. With the evolution of Web technologies more powerful linking languages (XLink and XPointer) have been proposed.Here we introduce XLinkProxy, a Web application that allows sophisticated hyperlink (defined using XLink and XPointer) to be defined outside referring documents, giving users the chance to build dynamic multidestination, multidirectional links databases.

In this paper we describe an experience in designing a groupware application distributed over the WWW to solve a conference management problem. The system we design coordinates the activities of several people engaged in reviewing and selecting papers submitted for a scientific conference. We discuss why such an application is interesting and describe how we designed it. The architecture we suggest implements what we call an active Web, because it includes entities which we are able to use and provide services offered through WWW infrastructures. Users, agents, and active documents can interoperate using a set of basic services for communication and synchronization. The active Web infrastructure we describe here is based on coordination technology integrated with Java.

The use of the World Wide Web as a communication medium for knowledge engineers and software designers is limited by the lack of tools for writing, sharing, and verifying documents written with design notations. For instance, the Z language has a rich set of mathematical characters, and requires graphic-rich boxes and schemas for structuring a specification document. It is difficult to integrate Z specifications and text on WWW pages written with HTML, and traditional tools are not suited for the task. On the other hand, a newly proposed standard for markup languages, namely XML, allows one to define any set of markup elements; hence, it is suitable for describing any kind of notation. Unfortunately, the proposed standard for rendering XML documents, namely XSL, provides for text-only (although sophisticated) rendering of XML documents, and thus it cannot be used for more complex notations. We present a Java-based tool for applying any notation to elements of XML documents. These XML documents can thus be shown on current-generation WWW browsers with Java capabilities. A complete package for displaying Z specifications has been implemented and integrated with standard text parts. Being a complete rendering engine, text parts and Z specifications can be freely intermixed, and all the standard features of XML (including HTML links and form elements) are available outside and inside Z specifications. Furthermore, the extensibility of our engine allows any additional notations to be supported and integrated with the ones we describe.

The original Web did not support multiuser, interactive applications. This shortcoming is being studied, and several approaches have been proposed to use the Web as a platform for programming Internet applications. However, most existing approaches are oriented to centralized applications at servers, or local programs within clients. To overcome this deficit, we introduce PageSpace, that is a reference architecture for designing interactive multiagent applications. We describe how we control agents in PageSpace, using variants of the coordination language Linda to guide their interactions. Coordination technology is integrated with the standard Web technology and the programming language Java. Several kinds of agents live in the PageSpace: user interface agents, personal homeagents, agents that implement applications, and agents which interoperate with legacy systems. Within our architecture, it is possible to support fault-tolerance and mobile agents as well.

Currently, the Web does not support distributed applications well. Existing approaches are oriented towards centralized applications at servers, or local programs within clients. To overcome this deficit, the PageSpace platform was designed for distributed, coordinated agents in the Web. We take a specific approach to coordinate agents in PageSpace applications, namely variants of coordination language Linda that support rules and services to guide their cooperation. This technology is integrated with the standard Web technology and the language Java. Several kinds of agents live in the PageSpace: user interface agents, personal home agents, the agents that implement applications, and the kernel agents of the platform. Within the architecture it is possible to support fault tolerance and mobile agents as well.