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This paper aims to assess recent foresight exercises applied to cities by evaluating three major issues. Have foresight practitioners understood cities complexity? Have urban planners used adequate tools to generate plausible future visions? Are city policy makers using foresight studies to limit urban uncertainty?

In total, 20 city foresight examples were selected which either have international relevance or which constitute good examples of future-oriented initiatives. Case studies were classified into five taxonomies: European Union initiatives; local initiatives; academic initiatives; corporate initiatives; and architectural initiatives. A set of assessment criteria was established: city complexity conceptualization; methodological approach; and study impact.

Preliminary research outcomes show growing doubts about the appropriateness of the foresight tools used in cities and about the competency of foresight practitioners in understanding the complex and dynamic nature of contemporary cities. Furthermore, policy makers do not seem to grasp the potential of foresight to formulate urban strategies.

Some of the initiatives studied are relatively recent, so impact analysis has been limited by available data. Mostly, secondary documented sources were used to validate cases’ assessment. Research suggests a number of areas in which foresight studies may have a practical application to the urban realm.

The value of the present work lies in the effort for assessing and improving forward-looking activities undertaken at cities through a set of criteria which take into consideration the complexity and diversity of contemporary cities.

The purpose of this paper is to examine the need to go beyond the “monumentalist” vision in restoration of built heritage and embrace principles of sustainability in this architectural practice.

Case studies as conceptual reference. Architectural typology.

The environmental crisis that is currently recognized as one of the most important problems that contemporary society must address urgently is a situation that still has not permeated enough in the practice of monumental restoration, which is still carried out using unlimited resources.

In that sense, the close relationship between the built and the natural environment as an essential ingredient of the vernacular is analysed.

Much of the sustainable principles, that have been put forward as an example to be followed, are elements that have hundreds of years in the constructive tradition.

In this context, vernacular architecture has much to contribute in the field of conservation by the enormous accumulated knowledge that its shapes, materials and social use represent.

This experience must be retrieved, but not as an aseptic laboratory experiment, but through its updated application and active implementation to improve the quality of life for inhabitants and contribute to the preservation of our cultural and natural environments.

To overview and discuss the technical, economical, legal, and social reasons why public key infrastructures (PKIs) have failed so far, summarizing the lessons learned, and giving expectations about the future development of the field.

A detailed analysis of the developments in the PKI field, pointing out the achievements so far and the issues that still remain unsolved.

The possible reasons for the failure of PKI technology.

Identifies and analyses the problems of PKIs considering the different perspectives, i.e. not only the technical issues but also other issues like the economical, legal, and social issues that have also influenced the failure of PKIs.

Distributed systems usually contain objects with heterogeneous security requirements that pose important challenges for the underlying security mechanisms and especially in access control systems. Access control in distributed systems often relies on centralised security administration. Existing solutions for distributed access control do not provide the flexibility and manageability required. This paper presents the XML‐based secure content distribution (XSCD) infrastructure, which is based on the production of protected software objects that convey contents (software or data) and can be distributed without further security measures because they embed the access control enforcement mechanism. It also provides means for integrating privilege management infrastructures (PMIs). Semantic information is used in the dynamic instantiation and semantic validation of policies. XSCD is scalable, facilitates the administration of the access control system, guarantees the secure distribution of the contents, enables semantic integration and interoperability of heterogeneous sources, provides persistent protection and allows actions (such as payment) to be bound to the access to objects.

This paper aims to analyze the security issues that arise when integrating wireless sensor networks (WSN) and the internet. Also, it seeks to review whether existing technology mechanisms are suitable and can be applied in this context.

The paper considers the possible approaches that can be used to connect a WSN with the internet, and analyzes the security of their interactions.

By providing the services of the network through a front‐end proxy, a sensor network and the internet can interact securely. There are other challenges to be solved if the sensor nodes are integrated into the internet infrastructure, although there exists interesting advances on his matter.

The complete integration of sensor networks and the internet still remains as an open issue.

With the current state of the art, it is possible to develop a secure sensor network that can provide its services to internet hosts with certain security properties.

The paper studies the interactions between sensor networks and the internet from the point of view of security. It identifies both solutions and research challenges.

The purpose of this paper is to verify the existence of financial constraints for investment in Brazil, an emerging market with growing international visibility.

Using panel data methodology and generalized method of moments (GMM), the paper estimates dynamic investment models based on the Euler equation and Tobin's q for a panel data set of 199 Brazilian non-financial firms for the time period 1995-2006.

Results show that Brazilian firms face financial constraints since their investments depend on internally generated funds. Results are robust to different investment models based on the Euler equation, also controlling for growth opportunities. Significant investment-cash flow sensitivity has been found for the whole sample of firms. Subsamples of firms considered as under financial constraints, according to dividend payout and equity issuance policies, have higher investment-cash flow sensitivity. Investment-cash flow sensitivity of financially constrained firms in Brazil is higher than that in the UK and in Romania, a transition economy.

The results extend empirical evidence of financial constraints in Brazil. The paper contributes to the literature by assessing the firms’ financial constraint status on an annual basis, and by using panel data methodology and GMM to estimate dynamic models of investment that take into account the proposals of the hierarchy of finance theory. In addition, the paper controls for growth opportunities. Capital market imperfections affect firm investment in Brazil and such effects are even stronger for financially constrained firms.

Provide a secure solution for web services (WS). A new interoperable and distributed access control for WS is presented.

Based on the separation of the access control (AC) and authorization function.

Mechanisms presented allow seamless integration of external authorization entities in the AC system. The Semantic Policy Language (SPL) developed facilitates specification of policies and semantic policy validation. SPL specifications are modular and can be composed without ambiguity. Also addressed was the problem of the association of policies to resources (WS or their operations) in a dynamic, flexible and automated way.

The ACProxy component is currently under development. Ongoing work is focused on achieving a richer “use control” for some types of WS.

Administrators of WS can specify AC policies and validate them to find syntactic and semantic errors. Components for automated validation of policies at different levels are included. This ensures that the AC policies produce the desired effects, facilitating the creation and maintenance of policies. It also provides mechanisms for the use of interoperable authorizations.

A practical system that provides a secure solution to AC for WS. To the best of one's knowledge, no other system provides mechanisms for semantic validation of policies based on external authorization entities. Likewise, the mechanisms for interoperability of external authorization entities are also novel. The system provides content‐based access control and a secure, decentralized and dynamic solution for authorization that facilitates the management of complex systems and enhances the overall security of the AC.

As a value‐added service to deliver important data over the internet with guaranteed receipt for each successful delivery, certified email has been discussed for years and a number of research papers appeared in the literature. This paper aims to present two optimized multi‐party certified email protocols.

Reviews two existing email protocols and provides a modified version to overcome their security flaws and weaknesses. Extends the two‐party protocol to a multi‐party scenario.

Both of the protocols have three major features. A sender could notify multiple recipients of the same information while only those recipients who acknowledged are able to get the information. Both the sender and the recipients can end a protocol run at any time without breach of fairness. The exchange protocols are optimized, each of which has only three steps, and the trusted third party will not be involved unless an exception (e.g. a network failure or a party's misbehavior) occurs.

Provides a focus on a value‐added service – certified email.

To provide a cryptographic protocol for anonymously accessing services offered on the web. Such anonymous accesses can be disclosed or traced under certain conditions.

The “traceable signature” scheme was used in conjunction with the “privilege management infrastructure”.

The cryptographic primitive provides a suitable tool for anonymous and unlinkable access to web resources based on the privileges that users hold. Moreover, the scheme allows for anonymity revocation and tracing of unlinkable accesses.

The power of the attribute authority should be divided into several entities, one of them being a trusted third party, to avoid illicit disclosing of information.

New systems with support for anonymous access to web resources can be developed.

This paper adds the unlinkability property to anonymous accesses together with a tracing facility to existing proposals.