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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.

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.

The purpose of this paper is to test a positive spiral of self-efficacy among public employees. The spiral proposes that self-efficacy is positively related to extra-role behaviors. These behaviors in turn are positively related to subsequent self-efficacy.

A total of 260 public employees participated in three waves of data collection: self-efficacy (T1); extra-role behaviors (T2); self-efficacy (T3).

The results confirmed the existence of a positive spiral of self-efficacy. There was a positive and significant link from self-efficacy of employees (T1) to extra-role behaviors (T2). In addition, it was found a positive and significant relationship between extra-role behaviors (T2) and subsequent self-efficacy (T3) once the link from self-efficacy in T1 and T3 was controlled for. The mediation role of extra-role behaviors was also confirmed.

The examination of positive spirals is one of the critical challenges of the investigation of personal resources. In the current research study, the authors test the positive spiral of a critical personal resource such as self-efficacy. Additionally, the lagged design permits a solid test of the aforementioned spiral.

This paper analyzes the effect of strategic context on managerial compensation design, and the interactive influence on firm performance for a set of Spanish companies. Specifically, this study examines the performance implications of the fit between different managerial compensation systems and diverse firm’s strategic orientations – representing various levels of managerial discretion. Based on a framework combining agency theory and managerial discretion concept, a research design with both archival and survey data is used to test hypotheses in a sample of 82 firms. The findings offer sufficient confirmation of theoretical arguments, providing extensions of this research stream for non‐U.S. firms. Results show that firms benefit from the design of managerial compensation systems when they match the managerial control and risk‐bearing requirements imposed by the strategic context. Specifically, risk‐encouraging compensation systems are better for prospector firms – high level of managerial discretion – whereas risk‐discouraging compensation systems are better for defender firms – low level of managerial discretion.

Discusses research ideas on the distinctions between data, information and knowledge, the categories of knowledge and knowledge‐processing activities in Holsapple and Whinston’s (HW’s) taxonomy (1987, 1988a, 1988b), and their application to markets and the activities of the firm. Describes a manufacturing firm’s inputs, production processes and outputs in terms of HW’s taxonomy, pointing out that management must filter the information surrounding the firm to turn it into knowledge of various types, e.g. descriptive, derived, assimilative etc. Considers the role of information for customers of and investors in the firm; and the relationship between knowledge and efficiency. Identifies three types of knowledge workers (builders, stewards and appliers) and calls for further research on the taxonomy of knowledge and standards of knowledge within the finance discipline.

Outlines the strategic challenges faced by multinationals (e.g. the conflict between globalization and localization, environmental volatility etc.) and argues that the use of nonlinear systems theory (chaos theory) can help. Explains how “phase planes” can provide insight into changes in the international environment and illustrates their use in choosing intervention strategies to respond to changing risk ratings in Mexico and Brazil over time. Summarizes the advantages of this dynamic approach over traditional linear analysis methods and believes that it can be universally applied to financial, operational or economic measures.

This work addresses what Michael E. Brown calls the immanence of sociality to individuality. It does so by focusing on the essentially social nature of human consciousness. I explore Durkheim’s analysis of human consciousness, beginning with totemism and concluding with his analysis of German consciousness at the time of World War I. I do so in order to provide some insight into the rise and nature of political movements, with a focus on extreme right wing political groups and leaders today as well as the spirit of the French Revolution in European and American history. With reference to Marx’s early writings on consciousness, spiritual nourishment, and the fettering of forces of production and his later writings on the critical significance of fetishism, and the role of “fictitious” capital, I conclude by claiming that bringing together the insights of Durkheim, Marx, and Spinoza can provide a way to analyze and address the interlocking social, political, economic, and cultural crises of today.

Outlines previous research on the effects of insider trading on share prices and reactions to the tightening up of US laws against illegal trading. Calculates returns for a sample of large managerial purchases made after the new legislation (1993‐1995) and announced in the Wall Street Journal to test for the presence of asymmetric information, agency conflicts and undervaluation; using firm size, market‐to‐book ratio, Q ratio and price‐earnings ratio as proxies. Finds that share prices react positively to large managerial purchases, especially if the firm is small, undervalued and/or experiencing conflicts between managers and shareholders; and that this effect is not reversed within a year.

This paper analyzes the links among executive compensation, a firm’s strategic orientation, and firm performance. A number of key questions relative to the relationships among these elements remain unanswered because prior research on this subject has reported mixed results, and, moreover, has been confined almost exclusively to U.S. firms. We develop a framework that draws on arguments from agency theory to identify such links. A research design with both archival and survey data is used to test hypotheses in a sample of 253 Spanish companies. We found that top managers’ compensation systems are linked with a firm’s strategic orientations, but in a different form than that of previous studies. Results show two differentiated groups of firms: (1) prospective firms that adapt their managerial compensation systems to the requirements of strategic context, consequently obtaining positive performance effects; and (2) conservative firms that design managerial compensation systems independent of strategic context, consequently not obtaining additional performance benefits.

Through a survey of 200 employees working in five of the thirty establishments analysed in previous research about the microeconomic effects of reducing the working time (Cahier 25), the consequences on employees of such a reduction can be assessed; and relevant attitudes and aspirations better known.