60,662 research outputs found
Resilience markers for safer systems and organisations
If computer systems are to be designed to foster resilient
performance it is important to be able to identify contributors to resilience. The
emerging practice of Resilience Engineering has identified that people are still a
primary source of resilience, and that the design of distributed systems should
provide ways of helping people and organisations to cope with complexity.
Although resilience has been identified as a desired property, researchers and
practitioners do not have a clear understanding of what manifestations of
resilience look like. This paper discusses some examples of strategies that
people can adopt that improve the resilience of a system. Critically, analysis
reveals that the generation of these strategies is only possible if the system
facilitates them. As an example, this paper discusses practices, such as
reflection, that are known to encourage resilient behavior in people. Reflection
allows systems to better prepare for oncoming demands. We show that
contributors to the practice of reflection manifest themselves at different levels
of abstraction: from individual strategies to practices in, for example, control
room environments. The analysis of interaction at these levels enables resilient
properties of a system to be ‘seen’, so that systems can be designed to explicitly
support them. We then present an analysis of resilience at an organisational
level within the nuclear domain. This highlights some of the challenges facing
the Resilience Engineering approach and the need for using a collective
language to articulate knowledge of resilient practices across domains
Architectural mismatch tolerance
The integrity of complex software systems built from existing components is becoming more dependent on the integrity of the mechanisms used to interconnect these components and, in particular, on the ability of these mechanisms to cope with architectural mismatches that might exist between components. There is a need to detect and handle (i.e. to tolerate) architectural mismatches during runtime because in the majority of practical situations it is impossible to localize and correct all such mismatches during development time. When developing complex software systems, the problem is not only to identify the appropriate components, but also to make sure that these components are interconnected in a way that allows mismatches to be tolerated. The resulting architectural solution should be a system based on the existing components, which are independent in their nature, but are able to interact in well-understood ways. To find such a solution we apply general principles of fault tolerance to dealing with arch itectural mismatche
A user-oriented network forensic analyser: the design of a high-level protocol analyser
Network forensics is becoming an increasingly important tool in the investigation of cyber and computer-assisted crimes. Unfortunately, whilst much effort has been undertaken in developing computer forensic file system analysers (e.g. Encase and FTK), such focus has not been given to Network Forensic Analysis Tools (NFATs). The single biggest barrier to effective NFATs is the handling of large volumes of low-level traffic and being able to exact and interpret forensic artefacts and their context – for example, being able extract and render application-level objects (such as emails, web pages and documents) from the low-level TCP/IP traffic but also understand how these applications/artefacts are being used. Whilst some studies and tools are beginning to achieve object extraction, results to date are limited to basic objects. No research has focused upon analysing network traffic to understand the nature of its use – not simply looking at the fact a person requested a webpage, but how long they spend on the application and what interactions did they have with whilst using the service (e.g. posting an image, or engaging in an instant message chat). This additional layer of information can provide an investigator with a far more rich and complete understanding of a suspect’s activities. To this end, this paper presents an investigation into the ability to derive high-level application usage characteristics from low-level network traffic meta-data. The paper presents a three application scenarios – web surfing, communications and social networking and demonstrates it is possible to derive the user interactions (e.g. page loading, chatting and file sharing ) within these systems. The paper continues to present a framework that builds upon this capability to provide a robust, flexible and user-friendly NFAT that provides access to a greater range of forensic information in a far easier format
Specification of complementary participatory methods for SEAMLESS-IF
Environmental Economics and Policy,
Recovering from External Disturbances in Online Manipulation through State-Dependent Revertive Recovery Policies
Robots are increasingly entering uncertain and unstructured environments.
Within these, robots are bound to face unexpected external disturbances like
accidental human or tool collisions. Robots must develop the capacity to
respond to unexpected events. That is not only identifying the sudden anomaly,
but also deciding how to handle it. In this work, we contribute a recovery
policy that allows a robot to recovery from various anomalous scenarios across
different tasks and conditions in a consistent and robust fashion. The system
organizes tasks as a sequence of nodes composed of internal modules such as
motion generation and introspection. When an introspection module flags an
anomaly, the recovery strategy is triggered and reverts the task execution by
selecting a target node as a function of a state dependency chart. The new
skill allows the robot to overcome the effects of the external disturbance and
conclude the task. Our system recovers from accidental human and tool
collisions in a number of tasks. Of particular importance is the fact that we
test the robustness of the recovery system by triggering anomalies at each node
in the task graph showing robust recovery everywhere in the task. We also
trigger multiple and repeated anomalies at each of the nodes of the task
showing that the recovery system can consistently recover anywhere in the
presence of strong and pervasive anomalous conditions. Robust recovery systems
will be key enablers for long-term autonomy in robot systems. Supplemental info
including code, data, graphs, and result analysis can be found at [1].Comment: 8 pages, 8 figures, 1 tabl
Rice and Water: The Final Frontier
Outlines the threat of diminishing water resources for rice crops, the economic and social dimensions of the droughts' potential effects, and the new cultural systems and adapted rice varieties being pursued as potential solutions
- …