Topological Performance Measures as Surrogates for Physical Flow Models for Risk and Vulnerability Analysis for Electric Power Systems

Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist that can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. In this article, we suggest a classification of these models, which span from simple topologically‐oriented models to advanced physical‐flow‐based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this article is to compare performance estimates achieved with a spectrum of approaches typically used for risk and vulnerability analysis of electric power systems and evaluate if more simplified topological measures can be combined using statistical methods to be used as a surrogate for physical flow models. The results of our work provide guidance as to appropriate models or combinations of models to use when analyzing large‐scale critical infrastructure systems, where simulation times quickly become insurmountable when using more advanced models, severely limiting the extent of analyses that can be performed.     

Path to “Stardom” in Globally Distributed Hybrid Teams: An Examination of a Knowledge‐Centered Perspective using Social Network Analysis

Although distributed teams have been researched extensively in information systems and decision science disciplines, a review of the literature suggests that the dominant focus has been on understanding the factors affecting performance at the team level. There has however been an increasing recognition that specific individuals within such teams are often critical to the team's performance. Consequently, existing knowledge about such teams may be enhanced by examining the factors that affect the performance of individual team members. This study attempts to address this need by identifying individuals who emerge as “stars” in globally distributed teams involved in knowledge work such as information systems development (ISD). Specifically, the study takes a knowledge‐centered view in explaining which factors lead to “stardom” in such teams. Further, it adopts a social network approach consistent with the core principles of structural/relational analysis in developing and empirically validating the research model. Data from U.S.–Scandinavia self‐managed “hybrid” teams engaged in systems development were used to deductively test the proposed model. The overall study has several implications for group decision making: (i) the study focuses on stars within distributed teams, who play an important role in shaping group decision making, and emerge as a result of a negotiated/consensual decision making within egalitarian teams; (ii) an examination of emergent stars from the team members’ point of view reflects the collective acceptance and support dimension decision‐making contexts identified in prior literature; (iii) finally, the study suggests that the social network analysis technique using relational data can be a tool for a democratic decision‐making technique within groups.     

Household debt and financial assets: evidence from Germany, Great Britain and the USA

Summary.  We explore the determinants of debt, financial assets and net worth at the household level by using survey data for Germany, Great Britain and the USA. To identify which households are potentially vulnerable to adverse changes in the economic environment, we also explore the determinants of a range of measures of financial pressure: the probability that a household has negative net worth; the debt-to-income ratio; mortgage income gearing; the saving-to-income ratio. Our empirical findings suggest that the poorest and the youngest households are the most vulnerable to adverse changes in their financial circumstances.     

The Permeable Border: Examining Responses to North American Integration in Video Art

Abstract

In this essay, I suggest that artistic production provides valuable insights into the nature of the Canada-US border during the late-twentieth century when significant changes were occurring to dominant understandings of Canada in relation to North America. Focusing on the medium of video art, I trace the sustained engagement of Canadian contemporary artists to respond to and comment on the move towards continental integration through free trade. I contextualize my discussion in relation to trade developments that opened Canada’s border with the US, such as the 1989 implementation of the Canada-US Free Trade Agreement. This agreement, along with the later North American Free Trade Agreement, led to increasing continental integration at the end of the twentieth century, as well as hope for hemispheric integration with the subsequent negotiations towards the Free Trade Area of the Americas. With attention to works by Lisa Steele and Kim Tomczak, Eva Manly, and Clive Robertson, I foreground cultural contributions to redefining the Canada-US borderlands. Here, I chart the artists’ intention to echo narratives of the border’s porousness and address the power dynamics between the Canadian state and its trade partners. Examining themes of cultural imperialism, colonialism, and national identity, I point to the importance of cultural production in assessing the borderlands and, more broadly, histories of free trade in North America.     

Complex Interrelations of Trait Vulnerabilities in Mothers and their Infants

Despite the developmental and clinical relevance of this area of inquiry, no studies have examined the interrelations of trait vulnerabilities in the affective, behavioral, and interpersonal domains between mothers and their infants. Thus, this study examined the interrelations of three trait vulnerabilities (i.e., negative affective intensity, impulsivity, and insecure attachment) between mothers and their 12‐ to 23‐month‐old infants, focusing in particular on the unique and interactive influence of these maternal trait vulnerabilities on the expression of and precursors to these traits in their infants. Mother–infant dyads (N = 101) completed several laboratory procedures, and mothers reported on their own and their infants' expressions of the trait vulnerabilities of interest. Findings from this study provide preliminary evidence for intergenerational relations between these traits and suggest that it is the confluence of trait vulnerabilities in mothers that relates to the early expression of some of these traits in infants.     

Fell runners and walking walls: towards a sociology of living landscapes and aesthetic atmospheres as an alternative to a Lakeland picturesque

This article draws on analysis of data generated by way of an ethnography of fell running in the English Lake District and suggests that participants who have lived and run in the area for many years experience a particular mode of aesthetic. The Lake District has long been valued for its outstanding scenery represented in the aesthetic of the picturesque comprising relatively static landscapes that should be conserved. Established fell runners who have run in the area for many decades apprehend and appreciate the landscape in more complex, rooted and situated ways. The anthropologist Ingold, distinguishes between landscape and landsceppan, and this insight is instructive for grasping the way in which the runners do not simply scope scenery but work with the land: they shape it and are shaped by it. Fell runners are elements within the living environment and along with walls, sheep, becks, sun, rain – what Ingold evocatively calls the ‘weather‐world’ – are mobile. Movement is central to their aesthetic, they enjoy not so much the scenic but rather a fellsceppan and do so through their fast eye‐gait‐footwork and their lively, variable occupation with the terrain. The fells infiltrate and interpenetrate the runners and movement through the fells generates a somatic aesthetic. The pleasure in turn breeds existential capital an embodied gratification that serves as an attractor that binds those who appreciate feelings of being alive with and in the fells.     

Estimating carbon storage in urban forests of New York City

Urban Ecosystems - Forests play an important role in mitigating many of the negative effects of climate change. One of the ways trees mitigate impacts of climate change is by absorbing carbon...