406,951 research outputs found
Dynamic deployment of context-aware access control policies for constrained security devices
Securing the access to a server, guaranteeing a certain level of protection over an encrypted communication channel, executing particular counter measures when attacks are detected are examples of security requirements. Such requirements are identi ed based on organizational purposes and expectations in terms of resource access and availability and also on system vulnerabilities and threats. All these requirements belong to the so-called security policy. Deploying the policy means enforcing, i.e., con guring, those security components and mechanisms so that the system behavior be nally the one speci ed by the policy. The deployment issue becomes more di cult as the growing organizational requirements and expectations generally leave behind the integration of new security functionalities in the information system: the information system will not always embed the necessary security functionalities for the proper deployment of contextual security requirements. To overcome this issue, our solution is based on a central entity approach which takes in charge unmanaged contextual requirements and dynamically redeploys the policy when context changes are detected by this central entity. We also present an improvement over the OrBAC (Organization-Based Access Control) model. Up to now, a controller based on a contextual OrBAC policy is passive, in the sense that it assumes policy evaluation triggered by access requests. Therefore, it does not allow reasoning about policy state evolution when actions occur. The modi cations introduced by our work overcome this limitation and provide a proactive version of the model by integrating concepts from action speci cation languages
Cities and climate change: Strategic options for philanthropic support
Now, more than ever, cities are at the front lines of U.S. climate action. As national action stalls,
there is still a daunting amount to be done in reducing human-generated climate emissions.
Fortunately, this report comes in the wake of a groundswell of initiatives to engage on climate
change by cities, countries, and states across the U.S. Several important and thorough reports
on the types of mitigation actions cities can take have recently been released. We already have
examples of cities taking significant leadership roles in reducing their own climate emissions,
from New York and Boston to Austin, Boulder, and Los Angeles - yet U.S. climate emissions
continue to rise, and cities have an outsized role to play.
The purpose of this project is to review current U.S. city climate activities in order to identify
areas where additional investment by foundations could help accelerate city action to reduce
urban greenhouse gas emissions. The focus of the inquiry is on aggressive actions cities can take
that significantly increase their âlevel of ambitionâ to achieve emissions reductions on an
accelerated timetable. City strategies on climate adaptation are not encompassed in this
project. [TRUNCATED
Modelling and Analysis Using GROOVE
In this paper we present case studies that describe how the graph transformation tool GROOVE has been used to model problems from a wide variety of domains. These case studies highlight the wide applicability of GROOVE in particular, and of graph transformation in general. They also give concrete templates for using GROOVE in practice. Furthermore, we use the case studies to analyse the main strong and weak points of GROOVE
Sustainability experiments in the agri-food system : uncovering the factors of new governance and collaboration success
In recent years, research, society and industry recognize the need to transform the agri-food system towards sustainability. Within this process, sustainability experiments play a crucial role in transforming the structure, culture and practices. In literature, much attention is given to new business models, even if the transformation of conventional firms toward sustainability may offer opportunities to accelerate the transformation. Further acceleration could be achieved through collaboration of multiple actors across the agri-food system, but this calls for a systems approach. Therefore, we developed and applied a new sustainability experiment systems approach (SESA) consisting of an analytical framework that allows a reflective evaluation and cross-case analysis of multi-actor governance networks based on business and learning evaluation criteria. We performed a cross-case analysis of four agri-food sustainability experiments in Flanders to test and validate SESA. Hereby, the key factors of the success of collaboration and its performance were identified at the beginning of a sustainability experiment. Some of the key factors identified were risk sharing and the drivers to participate. We are convinced that these results may be used as an analytical tool for researchers, a tool to support and design new initiatives for policymakers, and a reflective tool for participating actors
Recommended from our members
The National Transport Data Framework
Report by Professor Peter Landshoff (Cambridge University) and
Professor John Polak (Imperial College London) on a project for
the Department for Transport.
emails: [email protected] [email protected] NTDF is designed to be a resource for data owners to deposit descriptions
into a central catalogue, so that people can search for data and find data
and understand their characteristics. The value of this is to individuals, to
commercial organizations, and to public bodies. For example, services that
provide better information to travellers will help to make their journey
less stressful and persuade them to make more use of public transport.
Transport operators need very diverse information to help them
plan developments to their services: demographic, geographical, economic etc.
And policy makers need a similar range of information to help them decide
how to divide their budget and afterwards to evaluate how valuable it has
been.This work was supported by the Department for Transport (DfT)
When grassroots innovation movements encounter mainstream institutions: implications for models of inclusive innovation
Grassroots innovation movements (GIMs) can be regarded as initiators or advocates of alternative pathways of innovation. Sometimes these movements engage with more established science, technology and innovation (STI) institutions and development agencies in pursuit of their goals. In this paper, we argue that an important aspect to encounters between GIMs and mainstream STI institutions is the negotiation of different framings of grassroots innovation and development of policy models for inclusive innovation. These encounters can result in two different modes of engagement by GIMs; what we call insertion and mobilization. We illustrate and discuss these interrelated notions of framings and modes of engagement by drawing on three case studies of GIMs: the Social Technologies Network in Brazil, and the Honey Bee Network and People's Science Movements in India. The cases highlight that inclusion in the context of GIMs is not an unproblematic, smooth endeavour, and involves diverse interpretations and framings, which shape what and who gets included or excluded. Within the context of increasing policy interest, the analysis of encounters between GIMs and STI institutions can offer important lessons for the design of models of inclusive innovation and development
State intervention, local indebtedness, investment overheating and their systemic background during global crisis in China
This paper focuses on the immediate economic and systemic reasons of steadily increasing local government indebtedness and investment overheating in China. These two phenomena emerged between 2008 and 2011 as a direct consequence of an external shock caused by the global crisis and the subsequent internal reaction in the form of intensified stimulating state intervention. New chances for resource distribution and investments through state intervention mobilized distribution priorities and politically rational economic behavior of actors, characteristic to party-state systems. Locations of mobilization were defined by the decentralized Chinese system specifics along the intertwined institutional party-state structure. Systemic characteristics and its Chinese specifics together resulted in investment overheating, and steadily growing local indebtedness through large and state-owned enterprises and local governments. This process was further amplified by the characteristics of transforming economy in China as actors in the private sphere were mobilized by the increased input demand of those privileged by the systemic priorities of state intervention
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