17,335 research outputs found
Identifying Security-Critical Cyber-Physical Components in Industrial Control Systems
In recent years, Industrial Control Systems (ICS) have become an appealing
target for cyber attacks, having massive destructive consequences. Security
metrics are therefore essential to assess their security posture. In this
paper, we present a novel ICS security metric based on AND/OR graphs that
represent cyber-physical dependencies among network components. Our metric is
able to efficiently identify sets of critical cyber-physical components, with
minimal cost for an attacker, such that if compromised, the system would enter
into a non-operational state. We address this problem by efficiently
transforming the input AND/OR graph-based model into a weighted logical formula
that is then used to build and solve a Weighted Partial MAX-SAT problem. Our
tool, META4ICS, leverages state-of-the-art techniques from the field of logical
satisfiability optimisation in order to achieve efficient computation times.
Our experimental results indicate that the proposed security metric can
efficiently scale to networks with thousands of nodes and be computed in
seconds. In addition, we present a case study where we have used our system to
analyse the security posture of a realistic water transport network. We discuss
our findings on the plant as well as further security applications of our
metric.Comment: Keywords: Security metrics, industrial control systems,
cyber-physical systems, AND-OR graphs, MAX-SAT resolutio
Smart Grid Security: Threats, Challenges, and Solutions
The cyber-physical nature of the smart grid has rendered it vulnerable to a
multitude of attacks that can occur at its communication, networking, and
physical entry points. Such cyber-physical attacks can have detrimental effects
on the operation of the grid as exemplified by the recent attack which caused a
blackout of the Ukranian power grid. Thus, to properly secure the smart grid,
it is of utmost importance to: a) understand its underlying vulnerabilities and
associated threats, b) quantify their effects, and c) devise appropriate
security solutions. In this paper, the key threats targeting the smart grid are
first exposed while assessing their effects on the operation and stability of
the grid. Then, the challenges involved in understanding these attacks and
devising defense strategies against them are identified. Potential solution
approaches that can help mitigate these threats are then discussed. Last, a
number of mathematical tools that can help in analyzing and implementing
security solutions are introduced. As such, this paper will provide the first
comprehensive overview on smart grid security
EXAMINING QUALITY INDICATOR RATES FOR OLDER HOME CARE CLIENTS WITH DUAL SENSORY IMPAIRMENT (DSI) AND EXPLORING THE HETEROGENEITY WITHIN DSI.
Older adults with impairments in both hearing and vision, called dual sensory impairment (DSI), are at an increased risk of negative health outcomes such as impaired communication and difficulties with mobility. It is unknown whether DSI is associated with potential quality of care issues. This study used a set of home care quality indicators (HCQIs) to examine potential quality issues in older clients (65+) with DSI. Further, it looked to explore how HCQI rates differed based on the geographic region of care and whether the client’s level of hearing and vision impairment was related to certain HCQIs. The HCQIs were generated from data collected using the Resident Assessment Instrument for Home Care and capture undesirable outcomes (e.g., falls, cognitive decline). Higher rates indicate a greater frequency of experiencing the issue. In this sample (n=352,656), the average age was 82.8 years (sd=7.9), the majority were female (63.2%), and 20.5% experienced DSI. Compared to those without DSI, clients with DSI had higher rates across 20 of the 22 HCQIs. The HCQI rates differed by geographic region, with specific regions consistently performing worse than others. Finally, the level of hearing and vision impairment was related to certain HCQIs more than others, for example hearing impairment appeared to be more related to the quality indicator measuring communication difficulty. Overall, the hope is that this information can help to identify some of the potential issues around quality and in turn, assist in continually improving the services being provided to these clients
Underpaid or Overpaid? Wage Analysis for Nurses Using Job and Worker Attributes
The nursing labor market presents an apparent puzzle. Hospitals report chronic shortages, yet standard wage analysis shows that nursing wages have increased over time and greatly exceed those received by other college-educated women. This paper addresses this puzzle. Data from the Current Population Survey (CPS) are matched with detailed job content descriptors from the Occupational Information Network (O*NET). Nursing jobs require higher levels of skills and more difficult working conditions than do jobs for other college educated workers. A standard CPS-only wage regression shows a registered nurse (RN) wage advantage of .22 log points compared to a pooled male/female group of college-educated workers. Control for O*NET job attributes reduces the RN gap to .08, while an arguably preferable nonparametric estimator produces a wage gap estimate close to zero. We conclude that nurses receive compensation close to long-run opportunity costs, narrowing if not resolving the RN wage-shortage puzzle.nursing, wage differentials, job attributes
Continuous maintenance and the future – Foundations and technological challenges
High value and long life products require continuous maintenance throughout their life cycle to achieve required performance with optimum through-life cost. This paper presents foundations and technologies required to offer the maintenance service. Component and system level degradation science, assessment and modelling along with life cycle ‘big data’ analytics are the two most important knowledge and skill base required for the continuous maintenance. Advanced computing and visualisation technologies will improve efficiency of the maintenance and reduce through-life cost of the product. Future of continuous maintenance within the Industry 4.0 context also identifies the role of IoT, standards and cyber security
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