1,720,990 research outputs found
Enforcing workflow authorization constraints using triggers
No full textWorkflow design involves modeling different aspects of a business process as well as security requirements. This paper presents an approach based on triggers to specify and enforce workflow authorization constraints for a flexible assignment of tasks to roles and agents. The approach has been conceived in the framework of the WIDE workflow management system. Authorization triggers specify when and how the set of authorizations for a given workflow should be changed and which actions should be taken by the system or by the administrator. A basic set of triggers is provided enforcing security policies common to workflow systems. Methodological issues related to trigger design for a given workflow application are discussed and an approach based on authorization patterns is illustrated. The paper shows how authorization patterns can be instantiated into triggers and discusses briefly aspects related to the analysis of a set of authorization triggers defined for a given workflow applicatio
Fuzzy service selection in a distributed object-oriented environment
No full textIn network-centered execution environments, client objects can transparently invoke services offered by remote server objects, according to their published interface. The object selection problem requires the evaluation of the fitness of a pool of candidate server objects on the basis of the available information about their functional and nonfunctional features. Network-centered systems usually store such information in a trader agent that can be browsed or queried by client objects. In this paper, a fuzzy data model is proposed as the basis of the design of such a trader system, taking into account synergy between objects’ features. Our trader is based on a fuzzy query algebra allowing for deriving operator definitions (therefore, query execution mechanisms) at run time, on the basis of user-selected semantics
Improving Interaction in Integrated Chronic Care Management
Full text linkHealth and social care services are under increasing pressure to come up with adequate solutions to manage the demand and supply equation. Integrated care is one way to deal with this wicked problem, but new approaches and service implementation strategies are necessary to realize its full value and quality of outcome. Focusing on the four relevant ‘blocks of interaction’ identified by Prahalad and Ramaswamy, the paper examines the key role of information and communication technology (ICT) in facilitating the integrated care effort. It then develops those insights into a set of DART-informed guiding principles of practical use to decision-makers and IS/IT developers in the design of resource integration mechanisms for the management of chronic care settings. The paper uses home care services as a blueprint
Automated derivation of global authorizations for database federations
No full textGlobal authorizations in database federations can be derived from local authorizations exported by the databases composing the federation. Particularly, when several component databases participate in the federation and a high number of users and protection objects are involved, techniques are needed for defining and managing global access privileges. This paper describes an automated approach for the derivation of global authorizations according to the policy of decentralized minimum privilege, based on the analysis of authorizations exported by component databases. The approach rakes into account both the security requirements of the constituent databases, to preserve their local authorization autonomy, and cooperation requirements, to concurrently enable flexible data sharing between the constituent databases. A federation authorization model and abstraction criteria to derive global authorizations that are consistent with the exported local ones are presented. Different abstraction strategies can be applied for derivation, depending on the nature of the global objects to be protected and on the security requirements of the federated system
Managing Workflow Authorization Constraints Through Active Database Technology
No full textThe execution of workflow processes requires authorizations for enforcing the assignment of tasks to agents. either human or automated, according to the security policy of the organization. This paper presents a workflow authorization framework based on roles and organizational levels, and on authorization constraints. To facilitate the assignment of tasks to agents, roles and organizational levels are organized into hierarchies. Authorization constraints are introduced to specify instance-dependent, time-dependent. and history-dependent authorizations. Authorization constraints are specified in terms of active rules, used also for authorization management. The Workflow Management System determines authorized agents on the basis of the contents of an authorization base maintained through the active rules defined in the system
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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