A damage model based on failure threshold weakening

A variety of studies have modeled the physics of material deformation and damage as examples of generalized phase transitions, involving either critical phenomena or spinodal nucleation. Here we study a model for frictional sliding with long range interactions and recurrent damage that is parameterized by a process of damage and partial healing during sliding. We introduce a failure threshold weakening parameter into the cellular-automaton slider-block model which allows blocks to fail at a reduced failure threshold for all subsequent failures during an event. We show that a critical point is reached beyond which the probability of a system-wide event scales with this weakening parameter. We provide a mapping to the percolation transition, and show that the values of the scaling exponents approach the values for mean-field percolation (spinodal nucleation) as lattice size $L$ is increased for fixed $R$. We also examine the effect of the weakening parameter on the frequency-magnitude scaling relationship and the ergodic behavior of the model

LexOWL: A Bridge from LexGrid to OWL

The Lexical Grid project is an on-going community driven initiative that provides a common terminology model to represent multiple vocabulary and ontology sources as well as a scalable and robust API for accessing such information. In order to add more powerful functionalities to the existing infrastructure and align LexGrid more closely with various Semantic Web technologies, we introduce the LexOWL project for representing the ontologies modeled within the LexGrid environment in OWL (Web Ontology Language). The crux of this effort is to create a “bridge” that functionally connects the LexBIG (a LexGrid API) and the OWL API (an interface that implements OWL) seamlessly. In this paper, we discuss the key aspects of designing and implementing the LexOWL bridge. We compared LexOWL with other OWL converting tools and conclude that LexOWL provides an OWL mapping and converting tool with well-defined interoperability for information in the biomedical domain

Integrated management of hierarchical levels: towards a CAPE tool

The integration of decision-making procedures usually assigned to different hierarchical production systems requires the use of complex mathematical models and high computational efforts, in addition to the need of an extensive management of data and knowledge within the production systems. This work addresses this integration problem and proposes a comprehensive solution approach, as well as guidelines for Computer Aided Process Engineering (CAPE) tools managing the corresponding cyberinfrastructure. This study presents a methodology based on a domain ontology which is used as the connector between the introduced data, the different available formulations developed to solve the decision-making problem, and the necessary information to build the finally required problem instance. The methodology has demonstrated its capability to help exploiting different available decision-making problem formulations in complex cases, leading to new applications and/or extensions of these available formulations in a robust and flexible way.Peer ReviewedPostprint (author's final draft

Digital technology and governance in transition: The case of the British Library

Comment on the organizational consequences of the new information and communications technologies (ICTs) is pervaded by a powerful imagery of disaggregation and a tendency for ?virtual? forms of production to be seen as synonymous with the ?end? of bureaucracy. This paper questions the underlying assumptions of the ?virtual organization?, highlighting the historically enduring, diversified character of the bureaucratic form. The paper then presents case study findings on the web-based access to information resources now being provided by the British Library (BL). The case study evidence produces two main findings. First, radically decentralised virtual forms of service delivery are heavily dependent on new forms of capacity-building and information aggregation. Second, digital technology is embedded in an inherently contested and contradictory context of institutional change. Current developments in the management and control of digital rights are consistent with the commodification of the public sphere. However, the evidence also suggests that scholarly access to information resources is being significantly influenced by the ?information society? objectives of the BL and other institutional players within the network of UK research libraries

Housing professionalism in the United Kingdom: the final curtain or a new age?

The unusually large, predominantly municipal, housing sector in the UK has provided the context for a large occupational grouping of "housing managers" that has claimed professional status. However, within the post-1945 British welfare state this professional project enjoyed limited success and social housing remained a fragile professional domain. This article explores the consequences for housing professionalism of the recent displacement of the bureau-professional "organisational settlement" by that characterising an emerging "managerial state". Managerialism constitutes a clear challenge to established forms of "professionalism", especially a weak profession such as housing management. However, professionalism is temporally and culturally plastic. Hence, the demands of managerialism, within the specific context of New Labour's quest for "community" cohesion, may be providing opportunities for a new urban network professionalism founded on claims to both generic and specific skills and also a knowledge base combining abstraction with local concreteness. The prominence in these networks of erstwhile "housing" practitioners may become the basis for a new, quite different, professional project. This argument is developed through both conceptual exploration and reference to empirical research. The latter involves reference to recent work by the authors on, first, the perception of housing employers of the changing nature and demands of "housing" work and its consequences for professionalism and, secondly, the professional project implications of the increasing prominence of neighbourhood management.</p

"If they come they will build it" : managing and building e-democracy from the ground up

The possibilities for using online media to promote deliberative democracy and enhance civic participation have been identified by many. At the same time, the ‘e-democracy score card’ is decidedly mixed, with the tendency of established institutions in both government and the mainstream media to promote a ‘push’ model of communication and information provision, which fails to adapt to the decentralized, networked, interactive and many-to-many forms of communication enabled by the Internet. This paper will discuss the experience of the National Forum, which is building an Australian e-Democracy site of which is the first stage. It aims to be a combination of town-square, shopping centre of ideas, and producers’ co-operative which will allow citizens, talkers, agitators, researchers and legislators to interact with each other individually and through their organisations. Its aim will be to facilitate conversations, and where required, action. This project can be understood from a myriad of angles. At one level it is an open source journalism project, at another it deals with knowledge management. It can also be approached as a forum, an archive, an internet arketing initiative and an eCommerce resource for civil society. Central to the project is the development of feedback mechanisms so that participants can better understand the debates and where they stand in them as well as gauging the mood, desires and interests of the nation on a continuous basis. This paper deals with the practice, theories and economic models underlying the project, and considers the contribution of such sites to community formation and the development of social capital

From the 'governance of security' to 'governance failure' : refining the criminological agenda

Over the past three decades, an on-going debate has developed around the ways and extent to which the hierarchical, state-led provision of security and policing has been displaced by a move toward a polycentric, network-oriented mode of governance. This paper, firstly, analytically reconstructs the debate, suggesting that it is characterised by descriptive concordance, explanatory confluence, and normative dissonance. In other words, the major area of contention has been around the social and political implications of the State’s decentring by a networked provision of security, a transition that is accepted as having actually taken place. It is argued, secondly, that the debate has neglected to some considerable extent the inherent functional (as opposed to normative) limitations of networked governance, and that all parties to the debate may have been somewhat precipitous in accepting that such modes for delivering security can be functionally efficacious. Drawing on social theoretical explorations of ‘governance failure’, I identify three distinctive failure tendencies inherent in nodal networks, and evaluate their implications for the wider debate on the future of security provision