Search

OK, DNA! is an intuitive conversational interface designed to assist biologists and clinicians, who generally have little computer science expertise, in retrieving data from genomic databases. Through this novel technology, complex bioinformatics queries are abstracted to a dialogue interface, that does not require any specific knowledge on querying languages. The power of OK, DNA! is that it exploits the conversation with two goals - as a guide to assist biologists and clinicians during the creation of the entire search process, and as a natural language interface to formulate queries on multiple heterogeneous genomic datasets.

Data management is continuously evolving for serving the needs of an increasingly connected society. New challenges apply not only to systems and technology, but also to the models and abstractions for capturing new application requirements. In this paper, we describe several models and abstractions which have been progressively designed to capture new forms of data-centered interactions in the last twenty five years – a period of huge changes due to the spreading of web-based applications and the increasingly relevant role of social interactions. We initially focus on Web-based applications for individuals, then discuss applications among enterprises, then we discuss how these applications may include rankings which are computed using services or using crowds; we conclude with hints to a recent research discussing how social sources can be used for capturing emerging knowledge.

Social media response to catastrophic events, such as natural disasters or terrorist attacks, has received a lot of attention. However, social media are also extremely important in the context of planned events, such as fairs, exhibits, festivals, as they play an essential role in communicating them to fans, interest groups, and the general population. These kinds of events are geo-localized within a city or territory and are scheduled within a public calendar. We consider a specific scenario, the Milano Fashion Week (MFW), which is an important event in our city. We focus our attention on the coverage of social content in space, measuring the propagation of the event in the territory. We build different clusters of fashion brands, we characterize several features of propagation in space and we correlate them to the popularity of involved actors. We show that the clusters along space and popularity dimensions are loosely correlated, and that domain experts are typically able to understand and identify only popularity aspects, while they are completely unaware of spatial dynamics of social media response to the events.

As a wealth of data services is becoming available on the Web, building and querying Web applications that effectively integrate their content is increasingly important. However, schema integration and ontology matching with the aim of registering data services often requires a knowledge-intensive, tedious, and error-prone manual process. We tackle this issue by presenting a bottom-up, semi-automatic service registration process that refers to an external knowledge base and uses simple text processing techniques in order to minimize and possibly avoid the contribution of domain experts in the annotation of data services. The first by-product of this process is a representation of the domain of data services as an entity-relationship diagram, whose entities are named after concepts of the external knowledge base matching service terminology rather than being manually created to accommodate an application-specific ontology. Second, a three-layer annotation of service semantics (service interfaces, access patterns, service marts) describing how services “play” with such domain elements is also automatically constructed at registration time. When evaluated against heterogeneous existing data services and with a synthetic service dataset constructed using Google Fusion Tables, the approach yields good results in terms of data representation accuracy. We subsequently demonstrate that natural language processing methods can be used to decompose and match simple queries to the data services represented in three layers according to the preceding methodology with satisfactory results. We show how semantic annotations are used at query time to convert the user's request into an executable logical query. Globally, our findings show that the proposed registration method is effective in creating a uniform semantic representation of data services, suitable for building Web applications and answering search queries.

This article presents the adaptation of a general search computing framework for exploratory search over Web data as suggested by the specificity of location-based data services. The result is a conceptual model of geographic entities, the spatial functions operating on them, and a special-purpose exploratory interface that lets users search combinations of georeferenced objects directly on a map. Such modifications help the general framework provide ranked extraction of relevant objects and their combinations, custom ranking functions, and cost-based access to location-based services.

Search computing focuses on building answers to complex search queries (for example, "Where can I attend an interesting conference in my field near a sunny beach?") by interacting with a constellation of cooperating search services, and using result ranking and joining as the dominant factors for service composition. The service computing paradigm has so far been neutral to the specific features of search applications and services. To address this weakness, search computing advocates a new approach in which search, join, and ranking are the central aspects for service composition.

A combined approach of deductive and inductive reasoning can leverage the clear separation between the evolving (streaming) and static parts of online knowledge at conceptual and technological levels. What are the hottest topics discussed on Twitter? Which topics have my close friends discussed in the last hour? Which movie is my friend most likely to watch next? Which Tuscan red wine should I recommend? With many popular social networks publishing microblogs and feeds, the information required to answer these queries is becoming available on the Web.

In recent years, while search engines have become more and more powerful, several specialized search engines have been developed for different domains (e.g. library services, services dedicated to specific business sectors, geographic services, and so on). While such services beat generic search engines in their specific domain, they do not enable cross-references; therefore, they are of little use when queries require input from two or more of such services (e.g., ''find papers in VLDB 2000 authored by a member of a specified department'' or ''books sold online written by prolific database authors'' or ''vegetarian restaurants in the surroundings of San Francisco''). In this paper, we study how to join heterogeneous search engines and get a unique answer that satisfies conjunctive queries, where each query can be routed to a specialized engine. The paper includes both the theoretical framework for stating such problem and the description of pragmatic solutions based on web service technology. We present several algorithms for the efficient computation of join results under several cost model assumptions.

Accessibility has been recently defined by the W3C WAI (Web Accessibility Initiative) as the need to “create Web content that is perceivable, operable and understandable by the broadest range of users, and robust enough to work with current and future technologies” [WAI03]. The WAI initiative acts as the central point for setting accessibility guidelines for the Web; in addition, many other contributions in the literature propose accessibility criteria (see for example [TR03]). But the application of guidelines is often insufficient to guarantee accessibility; a recent research conducted on 1000 UK Web sites on behalf of the UK’s Disability Rights Commission [Hud04] demonstrates that most of these sites are quite hard to access, and that 45% of the discovered problems cannot be referred to WAI guidelines violations, but rather to unclear and confusing organization of pages, and confusing and disorienting navigation mechanisms.

Crowd-based computing is an increasingly popular paradigm for building Web applications, which uses the collective strength of human actors for performing tasks that are more suited to humans than computers. Interaction with the crowds was originally confined to specifically designed crowdsourcing platforms, such as Amazon Mechanical Turk. More recently, crowd-based computing has been reconsidered and extended, targeting social networks such as Facebook, Twitter, or LinkedIn, or including basic and direct interaction mechanisms, such as routing personal emails or tweets. Crowdsearcher, the system presented here, fosters interoperability and adaptation in crowd-based applications -- for example, the ability of supporting multiplatform applications and adapting them in reaction to events. This approach specifically supports dynamic interoperability (that is, the ability to modify the execution platforms while the application is ongoing) as a reaction to crowd behavior, which is hardly predictable. The authors show how to specify interoperability control at a high, declarative level and then implement it using active rules, thereby obtaining answers from crowds engaged in different communities. They also show the approach's effect on precision, delay, and cost.

Designing and maintaining Web applications is one of the major challenges for the software industry of the year 2000. In this paper we present Web Modeling Language (WebML), a notation for specifying complex Web sites at the conceptual level. WebML enables the high-level description of a Web site under distinct orthogonal dimensions: its data content (structural model), the pages that compose it (composition model), the topology of links between pages (navigation model), the layout and graphic requirements for page rendering (presentation model), and the customization features for one-to-one content delivery (personalization model). All the concepts of WebML are associated with a graphic notation and a textual XML syntax. WebML specifications are independent of both the client-side language used for delivering the application to users, and of the server-side platform used to bind data to pages, but they can be effectively used to produce a site implementation in a specific technological setting. WebML guarantees a model-driven approach to Web site development, which is a key factor for defining a novel generation of CASE tools for the construction of complex sites, supporting advanced features like multi-device access, personalization, and evolution management. The WebML language and its accompanying design method are fully implemented in a pre-competitive Web design tool suite, called ToriiSoft.

The integrated design of the Web interface and of data content gives several advantages in the design of data-intensive Web sites. The main objectives of this design process are (a) associating the Web with a high-level description of its content, that can be used for querying, evolution, and maintenance; (b) providing multiple views of the same data; (c) separating the de nition of information content from Web page composition, navigation, and presentation, which should be de ned independently and autonomously; (d) storing the meta-information collected during the design process within a repository used for the dynamic generation of Web pages; (e) collecting information about the Web site usage, obtained both statically (user registration) and dynamically (user tracking); (f) supporting selective access to information based on users' requirements and needs; (g) using business rules to improve the generation of e ective Web pages and to present each user with personalised views of the Web site. We identify ten general principles that should be considered when implementing a Web site managing large amounts of data, yielding the following decalogue

Commercial tools for software engineering include many development environments to support the design process. These integrated tools are usually distributed through traditional retail channels, with vendors increasingly giving customers the option of downloading products from the Web. The tools are installed on user client machines and are usually duplicated for actual tool use at customer sites. Users are responsible for installation, maintenance and upgrade procedures. We developed Web Lab as part of a project sponsored by the European Commission to advance rule-based, object-oriented technologies for developing database applications. The Web Lab was designed to help disseminate the research results. It enables remote use of a design environment for database applications, including a repository for application development that provides a protected workspace. However, as software becomes more and more a commodity, we expect vendors to begin selling software use rather than tools, an option that is particularly attractive in the context of thin clients running on network computers. Web Lab demonstrates the feasibility of this idea for commercial software distribution. We describe the Web Lab project, its implementation, and plans for further development.

Web search effectiveness is hampered by several factors, including the existence of several similar resources, ambiguous queries posed by users, and the varied profiles and objectives of users who submit the same query. This chapter focuses on recommendation and diversification techniques as possible solutions to these issues. Recommendation systems aim at predicting the level of preferences of users towards some items, with the purpose of suggesting ones they may like, among a set of elements they haven’t considered yet. Diversification is a technique that aims at removing redundancy in search results, with the purpose of reducing the information overload and providing more satisfying and diverse information items to the user. Both techniques, although typically “hidden behind the curtains” to the end user, result in dramatically enhancing user satisfaction with the performance of retrieval systems.

During the last 20 years a number of techniques to publish data on the Web have emerged. They range from the inexpensive approach of setting up a Web form to query a database, to the costly one of publishing Linked Data. So far none of these techniques has emerged as the preferable one, but search engine rich snippets are rapidly changing this game. Search engine optimization is becoming the driving business model for data publishing. This chapter surveys, in chronological order, the different techniques data owners have been using to publish data on the Web, provides a mean to comparatively evaluate them, and presents an outlook on the near future of Web data publishing.

Web users are increasingly relying on social interaction to complete and validate the results of their search activities. While search systems are superior machines to get world-wide information, the opinions collected within friends and expert/local communities can ultimately determine our decisions: human curiosity and creativity is often capable of going much beyond the capabilities of search systems in scouting "interesting" results, or suggesting new, unexpected search directions. Such personalized interaction occurs in most times aside of the search systems and processes, possibly instrumented and mediated by a social network; when such interaction is completed and users resort to the use of search systems, they do it through new queries, loosely related to the previous search or to the social interaction. In this paper we propose CrowdSearcher, a novel search paradigm that embodies crowds as first-class sources for the information seeking process. CrowdSearcher aims at filling the gap between generalized search systems, which operate upon world-wide information - including facts and recommendations as crawled and indexed by computerized systems - with social systems, capable of interacting with real people, in real time, to capture their opinions, suggestions, emotions. The technical contribution of this paper is the discussion of a model and architecture for integrating computerized search with human interaction, by showing how search systems can drive and encapsulate social systems. In particular we show how social platforms, such as Facebook, LinkedIn and Twitter, can be used for crowdsourcing search-related tasks; we demonstrate our approach with several prototypes and we report on our experiment upon real user communities.

With Fusion Tables, Google has made available a huge repository that allows users to share, visualize and manage structured data. Since 2009, thousands of tables have been shared online, encompassing data from virtually any domain and entered by all kinds of users, from professional to non-experts. While Fusion Tables are a potentially precious source of freely available structured information for all sorts of applications, complex querying and composing them is not supported natively, as it requires understanding both the structure and content of tables' data, which are heterogeneous and produced "bottom-up". In this paper, we discuss ongoing and future work concerning the integration of Fusion Tables in the aim of efficiently integrating, visualizing, and querying them.

In this chapter, we propose a set of methodological guidelines for defining exploratory search applications upon structured contents distributed on the Web and accessible through a service-oriented paradigm. We first motivate our work by describing our vision and our entity-based service registration framework; we then describe how applications can be designed by using a pattern-based method. Evidence of the feasibility of the approach is given by showing some deployed applications at work, and the general architecture of our software framework.

In many settings, the human opinion provided by an expert or knowledgeable user can be more useful than factual information retrieved by a search engine. Search systems do not capture the subjective opinions and recommendations of friends, or fresh, online-provided information that require contextual or domain-specific expertise. Search results obtained from conventional search engines can be complemented by crowdsearch, an online interaction with crowds, selected among friends, experts, or people who are presently at a given location; an interplay between conventional and search-based queries can occur, so that the two search methods can support each other. In this paper, we use a model-driven approach for specifying and implementing a crowdsearch application; in particular we define two models: the "Query Task Model", representing the meta-model of the query that is submitted to the crowd and the associated answers; and the "User Interaction Model", showing how the user can interact with the query model to fulfil her needs. Our solution allows for a top-down design approach, from the crowd-search task design, down to the crowd answering system design. Our approach also grants automatic code generation, thus leading to quick prototyping of crowd-search applications.

Recent years witnessed an exponential increase in the number of data services available on the Web. Many popular Web sites, including social networks, offer API for interacting with their information, and open data initiative such as the Linked Data project promise to achieve the vision of the Web of data. Unfortunately, access to Web data is typically limited by the constraints imposed by the query interface, and by technical limitations such as the network latency, or the number and frequency of allowed daily service invocations. Moreover, several sources may independently publish data about the same real-world objects; in such case, their combined use for assembling all available information about those objects requires duplicate removal, reconciliation and integration. This paper describes various data materialization problems, defining properties such as source coverage and data alignment of the materialized data, and then focuses on a specific problem, the reseeding of data access methods by using available information from previous calls in order to build a materialization of maximum size.

Current search engines do not support queries that require a complex combination of information. Problems such as "Which theatre offers an at least-three-stars action movie in London close to a good Italian restaurant" can only be solved by asking multiple queries, possibly to different search engines, and then manually combining results, thereby performing "data integration in the brain." While searching the Web is the preferred method for accessing information in everyday's practice, users expect that search systems will soon be capable of mastering complex queries. However, combining information requires a drastic change of perspective: a new generation of search computing systems is needed, capable of going beyond the capabilities of current search engines. In this paper we show how search computing should open to modular composition, as many other kinds of software computations. We first motivate our work by describing our vision, and then describe how the challenges of multi-domain search are addressed by a prototype framework, whose internal "anatomy" is disclosed.

Search Computing (SeCo) aims at building search applications that bridge the gap between general-purpose and vertical search engines. SeCo queries extract ranked information about several interconnected domains, such as "hotels", "restaurants" or "concerts", by interacting with Web data sources which are wrapped as search services; an example of query is: "Find a good Jazz concert close to the user's current location, together with close-by good restaurants and hotels". The SeCo system supports the deployment of search applications, by providing a generic software architecture and the tools for service and query registration, for query formulation and execution, and for result browsing. In this demo paper, we focus on the Liquid Query (LQ) interface which supports the iteration over query formulation, result visualization and query refinement, with commands for perusing the result set, changing the visualization of data based on their type (e.g., geographical or temporal) and interacting with the remote search services. It also supports an exploratory search approach, where the user starts by accessing one data source (e.g., an event listing for finding interesting concerts), then is assisted in progressively joining other correlated sources in an interactive exploration of the search space. The exploration paths can be chosen on the fly and the navigation history can be browsed back and forth for cross-checking the retrieved options.

Web search is considered a playground for a few giants—such as Google, Yahoo! and Bing—that relegate the other players to market niches. However, Web search is far from satisfying all information needs, because many search queries are complex, require information integration, and go beyond what can be offered by a single Web page; on these queries, generalized search engines do not perform well enough. This paper addresses a new paradigm for search-driven data integration, called Search Computing, based on combining data extraction from distinct sources and data integration by means of specialized integration engines. The Search Computing project has the ambitious goal of lowering the technological barrier required for building complex search applications, thereby enabling the development of many new applications which will cover relevant search needs.

Search Computing is a novel discipline that focuses on exploratory search of multi-domain Web queries like "Where can I attend an interesting conference in my field close to a sunny beach?". The approach is based on the interaction between cooperating search services, using ranking and joining of results as the dominant factors for service composition. This paper sketches the main characteristics of search computing and discusses how software engineering and model-driven engineering are challenged by the search computing problems. We present Search Computing applications from a model-driven perspective, in terms of (1) the models describing the objects of interest, (2) the specification of applications through model transformations, and (3) the definition of a domain specific language (DSL) defined for the specification of search query plans. This work provides a first exploration of MDE approaches applied to search computing and poses a set of challenges to the model transformation community.

Search Computing defines a new class of applications, which enable end users to perform exploratory search processes over multi-domain data sources available on the Web. These applications exploit suitable software frameworks and models that make it possible for expert users to configure the data sources to be searched and the interfaces for query submission and result visualization. We describe some usage scenarios and the reference architecture for Search Computing systems.

Search Computing (SeCo) is a project funded by the European Research Council (ERC). It focuses on building the answers to complex search queries like "Where can I attend an interesting conference in my field close to a sunny beach?" by interacting with a constellation of cooperating search services, using ranking and joining of results as the dominant factors for service composition. SeCo started on November 2008 and will last 5 years. This paper will give a general introduction to the Search Computing approach and then focus on its query optimization and execution engine, the aspect of the project which is most tightly related to "objects and databases" technologies.

This paper reports the main findings of a panel about trends in search engine interaction, focused upon the use of search engines for performing complex processes1. The discussion focuses on the different evolutionary path followed by search engines with respect to other Web and information management solutions, making end users acquainted with the simplistic and never changing keyword-based query paradigm. The analysis delves into the pros and cons of personalization, contextualization, and exploration of Web information, with special attention to the presentation and user interaction aspects. In the end, we also wonder if the keyword-based query paradigm will ever change.

In this paper we propose the Liquid Query paradigm, to support users in finding responses to multi-domain queries through exploratory information seeking across structured information sources (Web documents, deep Web data, and personal data repositories), wrapped by means of a uniform notion of search service. Liquid Query aims at filling the gap between general-purpose search engines, which are unable to find information spanning multiple topics, and domain-specific search systems, which cannot go beyond their domain limits. The Liquid Query interface consists of interaction primitives that let users pose questions and explore results spanning over multiple sources incrementally, thus getting closer and closer to the sought information. We demonstrate our approach with a prototype built upon the YQL (Yahoo! Query Language) framework.

“Who are the strongest European competitors on software ideas? Who is the best doctor to cure insomnia in a nearby hospital? Where can I attend an interesting conference in my field close to a sunny beach?” This information is available on the Web, but no software system can accept such queries nor compute the answer. We hereby propose search computing as a new multi-disciplinary science which will provide the abstractions, foundations, methods, and tools required to answer these and many similar queries. While state-of-art search systems answer generic or domain-specific queries, search computing enables answering questions via a constellation of dynamically selected, cooperating search services. Search computing requires innovation in software principles, languages, interfaces and protocols, as well as contributions from other sciences such as mathematics, operations research, psychology, sociology, economical and legal sciences.

Although Semantic Web Services are expected to produce a revolution in the development of Web-based systems, very few enterprise-wide design experiences are available; one of the main reasons is the lack of sound Software Engineering methods and tools for the deployment of Semantic Web applications. In this chapter, we present an approach to software development for the Semantic Web based on classical Software Engineering methods (i.e., formal business process development, computer-aided and component-based software design, and automatic code generation) and on semantic methods and tools (i.e., ontology engineering, semantic service annotation and discovery).

Search computing is a novel discipline whose goal is to answer complex, multi-domain queries. Such queries typically require combining in their results domain knowledge extracted from multiple Web resources; therefore, conventional crawling and indexing techniques, which look at individual Web pages, are not adequate for them. In this paper, we sketch the main characteristics of search computing and we highlight how various classical computer science disciplines - including software engineering, Web engineering, service-oriented architectures, data management, and human-computing interaction - are challenged by the search computing approach.

While business process definition is becoming more and more popular as an instrument for describing human activities, there is a growing need for software tools supporting business process abstractions to help users organize and monitor their desktop work. Tools are most effective when they embed some knowledge about the process, e.g., in terms of the typical activities required by the process, so that users can execute the activities without having to define them. Tools must be lightweight and flexible, so as to enable users to create or change the process as soon as there is a new need. In this article, we first describe an application-independent approach to flexible process support by discussing the abstractions required for modeling, creating, enacting, and modifying flexible processes. Then, we show our approach at work in the context of project-centered learning. In this application, learners are challenged to perform concrete tasks in order to master specific subjects; in doing so, they have to conduct significant projects and cope with realistic (or even real-life) working conditions and scenarios. Often, students are geographically dispersed or under severe timing constraints, because these activities intertwine with their normal university activity. As a result, they need communication technology in order to interact and workflow technology in order to organize their work. The developed platform provides a comprehensible, e-learning-specific set of activities and process templates, which can be combined through a simple Web interface into project-centered collaboration processes. We discuss how the general paradigm of flexible processes was adapted to the learning concept, implemented, and experienced by students.

Mashup languages offer new graphic interfaces for service composition. Normally, composition is limited to simple services, such as RSS or Atom feeds, but users can potentially use visual mashup languages for complex service compositions, with typed parameters and well-defined I/O interfaces. Composing search services introduces new issues, however, such as determining the optimal sequence of search invocations and separately composing ranked entries into a globally ranked result. Enabling end users to mash up services through suitable abstractions and tools is a viable option for improving service-based computations.

Where can I attend an interesting database workshop close to a sunny beach? Who are the strongest experts on service computing based upon their recent publication record and accepted European projects? Can I spend an April weekend in a city served by a low-cost direct flight from Milano offering a Mahler's symphony? We regard the above queries as multi-domain queries, i.e., queries that can be answered by combining knowledge from two or more domains (such as: seaside locations, flights, publications, accepted projects, conference offerings, and so on). This information is available on the Web, but no general-purpose software system can accept the above queries nor compute the answer. At the most, dedicated systems support specific multi-domain compositions (e.g., Google-local locates information such as restaurants and hotels upon geographic maps). This paper presents an overall framework for multi-domain queries on the Web. We address the following problems: (a) expressing multi-domain queries with an abstract formalism, (b) separating the treatment of "search" services within the model, by highlighting their differences from "exact" Web services, (c) explaining how the same query can be mapped to multiple "query plans", i.e., a well-defined scheduling of service invocations, possibly in parallel, which complies with their access limitations and preserves the ranking order in which search services return results; (d) introducing cross-domain joins as first-class operation within plans; (e) evaluating the query plans against several cost metrics so as to choose the most promising one for execution. This framework adapts to a variety of application contexts, ranging from end-user-oriented mash-up scenarios up to complex application integration scenarios.

Although Semantic Web Services are expected to produce a revolution in the development of Web-based systems, very few concrete design experiences are available; only recently, Software Engineering methods and tools have started to embrace the deployment of Semantic Web applications. In this paper, we show how classical Software Engineering methods (i.e., formal business process development, computer-aided and component-based software design, and automatic code generation) combine with semantic methods and tools (i.e., ontology engineering, semantic service annotation and discovery) to forge a new approach to software development for the Semantic Web. In particular, we present our experience in the participation to the Semantic Web Service (SWS) challenge 2006, where the proposed approach achieved very good results in solving the proposed problems.

Research in data management at Politecnico di Milano has a long and solid tradition; forefront books on distributed databases, conceptual database design, logical databases, and active databases contributed to shape the foundations of this discipline in the last two decades. Historically, our work has addressed both all aspects of innovation in the technology of modern data management systems and the consequent support of design methods and tools.

This work presents a retrospective analysis of how we have addressed new challenges in Web technologies and applications. WebML, which was first defined about 10 years ago, has been an incubator for research concerning abstractions, methods, tools, and technologies, acting as a glue within a group of people spread among universities, technology transfer centres, and a spin-off. In this paper, we first illustrate the common approach to innovation, and then show such approach at work in two contexts. One of them, dealing with "Service-Oriented Architectures" (SOA), has reached a mature state; the other one, "Semantic Web Services" (SWS), is at its infancy, but promises to deliver very interesting results in the forthcoming years.

More and more Web users ask for contents and services highly tailored to their particular contexts of use. Especially due to the increasing affordability of new and powerful mobile communication devices, they also appreciate the availability of ubiquitous access, independent from the device actually in use. Due to such premises, traditional software design methods need to be extended, and new issues and requirements need to be addressed for supporting context-aware access to services and applications. In this paper we propose a model-driven approach towards adaptive, context-aware Web applications, accompanied by a general-purpose execution framework enabling active context-awareness. Whereas conventional adaptive hypermedia systems address the problem of adapting HTML pages in response to user-generated requests, in this work we especially stress the importance of user-independent, context-triggered adaptivity actions. This finally leads us to interpret the context as an active actor, operating independently from users during their navigations.

Finding a previously visited page during a Web navigation is avery common and important kind of interaction. Most commercialbrowsers incorporate history mechanisms, which typically aresimple indexes of visited pages, sorted according to the timedimension. Such mechanisms are not very effective and are quitefar from giving users the impression of a semantically aware,long-term memory, as it is available to the human brain. Inparticular they lack associative, semantic-based mechanisms thatare essential for supporting information retrieval. This paperintroduces xMem (eXtended Memory Navigation) as a new method toaccess users' navigation history, based upon semantic andassociative access. Its aim is to emulate some of the features ofthe human memory, so as to give users a better understanding ofthe context of their searches, by exploiting semantic cuescharacterizing contents of visited pages.

This paper presents a CASE tool for the high-level specification of web applications integrated with web services. The CASE tool is based on WebML, a conceptual modelling language used for the specification of the front end of web applications. WebML, extended with new primitives for modelling web services, allows one to specify complex interactions between a web application, driven by the user, and remote processes, represented by services. The CASE tool also allows the specification and deployment of application functionalities as web services and automatically generates the running code, including web pages, web services calls and the exposed web services. In this paper, we describe the primitives for web services modelling, the architecture of the CASE tool for designing the applications, and the runtime architecture of the generated applications. Finally, we give an overview of some industrial applications developed with the described approach.

We present a framework for designing and developing Semantic Web Service applications that span over several enterprises by applying techniques, methodologies, and notations offered by Software engineering, Web engineering, and Business Process modeling. In particular, we propose to exploit existing standards for the specification of business processes (e.g., BPMN), for modeling the cross enterprise process, combined with powerful methodologies, tools and notations (e.g., WebML) borrowed from the Web engineering field for designing and developing semantically rich Web applications, with semi-automatic elicitation of semantic descriptions (i.e., WSMO Ontologies, Goals, Web Services and Mediators) from the design of the applications, with huge advantages in terms of efficiency of the design and reduction of the extra work necessary for semantically annotating the information crossing the organization boundaries.

The Adaptive Web is a new research area addressing the personalization of the Web experience for each user. In this paper we propose a new high-level model for the specification of Web applications that take into account the manner users interact with the application for supplying appropriate contents or gathering profile data. We therefore consider entire processes (rather than single properties) as smallest information units, allowing for automatic restructuring of application components. For this purpose, a high-level Event-Condition-Action (ECA) paradigm is proposed, which enables capturing arbitrary (and timed) clicking behaviors.

Significant efforts are currently invested in application integration to enable the interaction and composition of business processes of different companies, yielding complex; multi-party processes. Web service standards, based on WSDL, have been adopted as a process-to-process communication paradigm. This paper presents an industrial experience in integrating data-intensive and process-intensive Web applications through Web services. Design of sites and of Web services interaction exploits modern Web engineering methods, including conceptual modeling, model verification, visual data marshalling and automatic code generation. In particular, the applied method is based on a declarative model for specifying data-intensive Web applications that enact complex interactions, driven by the user, with remote processes implemented as services. We describe the internal architecture of the CASE tool that has been used, and give an overview of three industrial applications developed with the described approach.

The Adaptive Web is a new research area addressing the personalization of the Web experience for each user. In this paper we propose a new high-level model for the specification of Web applications that take into account the manner users interact with the application for supplying appropriate contents or gathering profile data. We therefore consider entire processes (rather than single properties) as smallest information units, allowing for automatic restructuring of application components. For this purpose, a high-level Event-Condition-Action (ECA) paradigm is proposed, which enables capturing arbitrary (and timed) clicking behaviors. Also, a possible architecture as well as a first prototype implementation are discussed.

While Web applications evolve towards ubiquitous, enterprise-wide or multi-enterprise information systems, their features must cover new requirements, such as the capability of managing complex processes spanning multiple users and organizations, by interconnecting software provided by different organizations. Significant efforts are currently being invested in application integration, to support the composition of business processes of different companies, so as to create complex, multi-party business scenarios. In this setting, Web applications, which were originally conceived to allow the user-to-system dialogue, are extended with Web services, which enable system-to-system interaction, and with process control primitives, which permit the implementation of the required business constraints. This talk presents new Web engineering methods for the high-level specification of applications featuring business processes and remote services invocation. Process- and service-enabled Web applications benefit from the high-level modeling and automatic code generation techniques that have been fruitfully applied to conventional Web applications, broadening the class of Web applications that take advantages of these powerful software engineering techniques. All the concepts presented in this talk are fully implemented within a CASE tool.

Significant effort is currently invested in application integration, enabling business processes of different companies to interact and form complex multiparty processes. Web service standards, based on WSDL (Web Service Definition Language), have been adopted as process-to-process communication paradigms. However, the conceptual modeling of applications using Web services has not yet been addressed. Interaction with Web services is often specified at the level of the source code; thus, Web service interfaces are buried within a programmatic specification.In this article, we argue that Web services should be considered first-class citizens in the specification of Web applications. Thus, service-enabled Web applications should benefit from the high-level modeling and automatic code generation techniques that have long been advocated for Web application design and implementation. To this end, we extend a declarative model for specifying data-intensive Web applications in two directions: (i) high-level modeling of Web services and their interactions with the Web applications which use them, and (ii) modeling and specification of Web applications implementing new, complex Web services.Our approach is fully implemented within a CASE tool allowing the high-level modeling and automatic deployment of service-enabled Web applications.