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

Collaboration in electronic resource provision in university libraries: SHEDL, a Scottish case study

This case study examines the growth of collaboration among Scottish higher education institutions. Following a summary of the work of the Scottish Confederation of University and Research Libraries (SCURL), more detailed information is provided on collaboration in the fields of acquisition, licensing, selection, and purchasing. Some of the UK background is outlined, relating to NESLi2 in particular, in order to illuminate the options within Scotland. The origins of negotiations on electronic resource provision within Scotland are described, drawing on developments in other countries including Ireland and Scandinavia. After initial setbacks, the implementation of the Scottish Higher Education Digital Library (SHEDL) from 2007 to 2009 is detailed. Current benefits arising from SHEDL are explained, and some possible future developments are discussed

The collection efficiency of the Value Added Tax: Theory and international evidence

This paper evaluates the political economy and structural factors explaining the collection efficiency of the Value Added Tax (VAT), where the collection efficiency is determined by the probability of audit and by the penalty on underpaying, and implementation lags imply that the present policy maker determines the efficiency of the tax system next period. Theory suggests that the collection efficiency is affected by political economy considerations - greater polarization and political instability would reduce the efficiency of the tax collection, and collection is impacted by structural factors affecting the ease of tax evasion (such as urbanization, agriculture share, openness). We evaluate the VAT collection efficiency (VAT revenue over the aggregate consumption divided by the standard VAT rate) in a panel of 44 countries over 1970-99. A one standard deviation increase in durability of political regime, and in the ease and fluidity of political participation, increases the VAT collection efficiency by 3.1% and 3.6%, respectively. A one standard deviation increase in urbanization, trade openness and the share of agriculture, changes the VAT collection efficiency by 12.7%, 3.9% and -4.8%, respectively. Qualitatively identical results apply for the ratio of VAT revenue to GDP divided by the standard VAT

Transatlantic Issues in Electronic Commerce

The global and dynamic e-commerce marketplace will increasingly impact the nature of national and international economic and government relations. This paper highlights three areas where the United States and European Union (EU) governments differ in their approaches as to how best to serve their domestic constituencies: treatment of trade flows, approach to tax regimes, manner of protecting personal data. Because the Internet marketplace is global but policy jurisdictions remain local, policy conflicts can develop. Policymakers on both sides need to harness technology and promote incentives for the private sector to help solve problems caused by the jurisdictional overlap. In addition to cross-border jurisdictional overlap, problems within a country can develop from issue convergence and policy overlap. That is, because the e-commerce marketplace is so integrated, the policy toward handling one issue, even within the national context, has implications for the policy set that is available to policymakers on other issues. Therefore, policies within a country must be more carefully meshed with each other with an eye toward consistency in the face of the forces of electronic commerce.transatlantic issues, electronic commerce

A Network Topology Approach to Bot Classification

Automated social agents, or bots, are increasingly becoming a problem on social media platforms. There is a growing body of literature and multiple tools to aid in the detection of such agents on online social networking platforms. We propose that the social network topology of a user would be sufficient to determine whether the user is a automated agent or a human. To test this, we use a publicly available dataset containing users on Twitter labelled as either automated social agent or human. Using an unsupervised machine learning approach, we obtain a detection accuracy rate of 70%

Sex Hormone-Binding Globulin Levels Are Inversely Associated With Nonalcoholic Fatty Liver Disease in HIV-Infected and -Uninfected Men.

BackgroundNonalcoholic fatty liver disease (NAFLD) is a leading cause of liver disease worldwide. Elevated sex hormone-binding globulin (SHBG) levels have been observed in the setting of HIV and may protect against some metabolic disorders. We aimed to investigate whether higher SHBG levels may protect against NAFLD in men with/without HIV.MethodsNAFLD was assessed using noncontrast computed tomography in 530 men in the Multicenter AIDS Cohort Study (MACS) who drank <3 alcoholic drinks/d and were uninfected with chronic hepatitis C or B (340HIV+, 190HIV-). Morning serum samples were tested for SHBG, total testosterone (TT), and adiponectin. Multivariable logistic regression was used to assess associations between HIV, SHBG, TT, adiponectin, and NAFLD.ResultsMedian SHBG was highest among HIV+/NAFLD- men and lowest among HIV-/NAFLD+ men. Adjusted for demographics, HIV, visceral adiposity, HOMA-IR, TT, and PNPLA3 genotype, higher SHBG was associated with lower odds of NAFLD (odds ratio [OR], 0.52 per doubling; 95% confidence interval [CI], 0.34-0.80). In separate multivariable models without SHBG, HIV (OR, 0.46; 95% CI, 0.26-0.79) and higher adiponectin (OR, 0.66 per doubling; 95% CI, 0.49-0.89) were associated with lower NAFLD odds, whereas TT was not significantly associated (OR, 0.74 per doubling; 95% CI, 0.53-1.04). Adjusting for SHBG attenuated the associations of HIV (OR, 0.61; 95% CI, 0.34-1.08) and adiponectin (OR, 0.74; 95% CI, 0.54-1.02) with NAFLD.ConclusionsSHBG levels were higher among HIV+ men, were independently associated with lower NAFLD, and could partially explain the associations of HIV and higher adiponectin with lower NAFLD in our cohort. These findings suggest that SHBG may protect against NAFLD, supporting further prospective and mechanistic studies

Can mothers judge the size of their newborn? Assessing the determinants of a mother's perception of a baby's size at birth

Birth weight is known to be closely related to child health, although as many infants in developing countries are not weighed at birth and thus will not have a recorded birth weight it is difficult to use birth weight when analysing child illness. It is common to use a proxy for birth weight instead, namely the mother’s perception of the baby’s size at birth. Using DHS surveys in Cambodia, Kazakhstan and Malawi the responses to this question were assessed to indicate the relationship between birth weight and mother’s perception. The determinants of perception were investigated using multilevel ordinal regression to gauge if they are different for infants with and without a recorded birth weight, and to consider if there are societal or community influences on perception of size. The results indicate that mother’s perception is closely linked to birth weight, although there are other influences on the classification of infants into size groups. On average, a girl of the same birth weight as a boy will be classified into a smaller size category. Likewise, infants who died by the time of the survey will be classified as smaller than similarly heavy infants who are still alive. There are significant variations in size perception between sampling districts and clusters, indicating that mothers mainly judge their child for size against a national norm. However, there is also evidence that the size of infants in the community around the newborn also has an effect on the final size perception classification. Overall the results indicate that mother’s perception of size is a good proxy for birth weight in large nationally representative surveys, although care should be taken to control for societal influences on perception

Investigating the role of VAT in the changing landscape of Educational Services: A case study of a digital educational services provider

Given the funding crisis in South African universities, investigation was carried out with respect to the role which Value Added Tax (VAT) plays in the educational services sector. It was found that there are difficulties in accounting for and apportioning VAT due to the diversification of revenue streams, especially with historically government-funded institutions. Furthermore, it was found that the application of current VAT legislation can face difficulties in regards to application of legislation with the move towards digital educational services providers, especially when looking at the role of agency through providing digital educational services on behalf of another institution. Lastly, the role of the VAT exempt status of educational services was seen to be one which can be improved upon so as to remove inefficiencies in the funding process of governmentally funded institutions, and to possible remove the benefit afforded to privately owned institutions

Evaluation of European electric vehicle support schemes

Electric vehicles can reduce carbon dioxide emissions, increase energy efficiency, and help to reduce the dependency on oil imports. However, today's technical and economic challenges are preventing mass-market adoption. In order to create an early market and support economies of scale in production, some European countries have already established support schemes. This research study aims to provide an overview of the existing support schemes in Europe and to assess them using four criteria: effectiveness, efficiency, practicability, and political acceptance. The study concludes with an impact analysis of today's economic support schemes which considers the total costs of ownership. While one-time support schemes help to reduce the large initial investments for EVs, recurring instruments are often more effective and efficient but also smaller in volume. The comparison of the different regional incentive schemes reveals that EVs today are only economically attractive in Denmark and Norway, but at relatively high prices. Thus, regulators need to increase the volume and efficiency of the support schemes, establish high scoring instruments, and align these on a European scale. In addition, non-monetary support, e.g. free-parking, can help to overcome technical or smaller economic hurdles. --

Working Paper 86 - A Review of Ex - ante Poverty Impact Assessments of Macroeconomic Policies in Cameroon and Ghana

This paper summarizes two extensive case studies of experiences with ex-ante poverty impact assessments of macroeconomic policies in Cameroon and Ghana during the last ten years. The paper provides a short description and critique of the studies and models that have been used in one way or the other for such assessments. It shows that much more needs to be done to provide policy makers with critical information to reduce poverty more effectively. The paper also reviews briefly the key institutional issues that constrain the more extensive analysis of the impact of macroeconomic policies on poverty, which are related to data constraints, capacity constraints, and power structures. The paper closes with a variety of recommendations, covering methodological, political, and data issues as well as suggestions for more evidence-based policy-making.