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Multiple line outages that occur together show a variety of spatial patterns in the power transmission network. Some of these spatial patterns form network contingency motifs, which we define as the patterns of multiple outages that occur much more frequently than multiple outages chosen randomly from the network. We show that choosing N-k contingencies from these commonly occurring contingency motifs accounts for most of the probability of multiple initiating line outages. This result is demonstrated using historical outage data for two transmission systems. It enables N-k contingency lists that are much more efficient in accounting for the likely multiple initiating outages than exhaustive listing or random selection. The N-k contingency lists constructed from motifs can improve risk estimation in cascading outage simulations and help to confirm utility contingency selection.

We quantify resilience with metrics extracted from the historical outage data that is routinely recorded by many distribution utilities. The outage data is coordinated with wind data to relate average outage rates in an area to wind speed measured at a nearby weather station. A past investment in wind hardening would have reduced the outage rates, and the effect of this on metrics can be calculated by sampling a reduced number of historical outages and recomputing the metrics. This quantifies the impact that the hardening would have had on customers. This is a tangible way to relate an investment in wind resilience to the benefits it would have had on the lived experience of customers that could help make the case for the investment to the public and regulators. We also quantify the impact of earlier or faster restoration on customer metrics and compare this to the impact of investment in hardening. Overall, this is a new and straightforward approach to quantify resilience and justify resilience investments to stakeholders that is directly driven by utility data. The approach driven by data avoids complicated models or modeling assumptions.

It is well known that interdependence between electric power systems and other infrastructures can impact energy reliability and resilience, but it is less clear which particular interactions have the most impact. There is a need for methods that can rank the relative importance of these interdependencies. This paper describes a new tool for measuring resilience and ranking interactions. This tool, known as Computing Resilience of Infrastructure Simulation Platform (CRISP), samples from historical utility data to avoid many of the assumptions required for simulation-based approaches to resilience quantification. This paper applies CRISP to rank the relative importance of four types of interdependence (natural gas supply, communication systems, nuclear generation recovery, and a generic restoration delay) in two test cases: the IEEE 39-bus test case and a 6394-bus model of the New England/New York power grid. The results confirm industry studies suggesting that a loss of the natural gas system is the most severe specific interdependence faced by this region.

We discuss ways to measure duration in a power transmission system resilience event by modeling outage and restore processes from utility data. We introduce novel Poisson process models that describe how resilience events progress and verify that they are typical using extensive outage data collected across North America. Some usual duration metrics show impractically high statistical variability, and we recommend new duration metrics that perform better. Moreover, the Poisson process models have parameters that can be estimated from observed network data under different weather conditions, and are promising new models of typical resilience events.

Security concerns have been raised about cascading failure risks in evolving power grids. This article reveals, for the first time, that the risk of cascading failures can be increased at low network demand levels when considering security-constrained generation dispatch. This occurs because critical transmission corridors become very highly loaded due to the presence of centralized generation dispatch, e.g., large thermal plants far from demand centers. This increased cascading risk is revealed in this work by incorporating security-constrained generation dispatch into the risk assessment and mitigation of cascading failures. A security-constrained AC optimal power flow, which considers economic functions and security constraints (e.g., network constraints, $N - 1$ security, and generation margin), is used to provide a representative day-ahead operational plan. Cascading failures are simulated using two simulators, a quasi-steady state DC power flow model, and a dynamic model incorporating all frequency-related dynamics, to allow for result comparison and verification. The risk assessment procedure is illustrated using synthetic networks of 200 and 2,000 buses. Further, a novel preventive mitigation measure is proposed to first identify critical lines, whose failures are likely to trigger cascading failures, and then to limit power flow through these critical lines during dispatch. Results show that shifting power equivalent to 1% of total demand from critical lines to other lines can reduce cascading risk by up to 80%.

Poisson process models are defined in terms of their rates for outage and restore processes in power system resilience events. These outage and restore processes easily yield the performance curves that track the evolution of resilience events, and the area, nadir, and duration of the performance curves are standard resilience metrics. This letter analyzes typical resilience events by analyzing the area, nadir, and duration of mean performance curves. Explicit and intuitive formulas for these metrics are derived in terms of the Poisson process model parameters, and these parameters can be estimated from utility data. This clarifies the calculation of metrics of typical resilience events, and shows what they depend on. The metric formulas are derived with lognormal, exponential, or constant rates of restoration. The method is illustrated with a typical North American transmission event. Similarly nice formulas are obtained for the area metric for empirical power system data.

This paper summarizes the report prepared by an IEEE PES Task Force. Resilience is a fairly new technical concept for power systems, and it is important to precisely delineate this concept for actual applications. As a critical infrastructure, power systems have to be prepared to survive rare but extreme incidents (natural catastrophes, extreme weather events, physical/cyber-attacks, equipment failure cascades, etc.) to guarantee power supply to the electricity-dependent economy and society. Thus, resilience needs to be integrated into planning and operational assessment to design and operate adequately resilient power systems. Quantification of resilience as a key performance indicator is important, together with costs and reliability. Quantification can analyze existing power systems and identify resilience improvements in future power systems. Given that a 100% resilient system is not economic (or even technically achievable), the degree of resilience should be transparent and comprehensible. Several gaps are identified to indicate further needs for research and development.

Earthquakes cause outages of power transmission system components due to direct physical damage and also through the initiation of cascading processes. This article explores what are the optimal capacity investments to increase the resilience of electric power transmission systems to earthquakes and how those investments change with respect to two issues: (1) the impact of including cascades in the investment optimization model and (2) the impact of focusing more heavily on the early stages of the outages after the earthquake in contrast to more evenly focusing on outages across the entire restoration process. A cascading outage model driven by the statistics of sample utility data is developed and used to locate the cascading lines. We compare the investment plans with and without the modeling of the cascades and with different levels of importance attached to outages that occur during different periods of the restoration process. Using a case study of the Eastern Interconnect transmission grid, where the seismic hazard stems mostly from the New Madrid Seismic Zone, we find that the cascades have little effect on the optimal set of capacity enhancement investments. However, the cascades do have a significant impact on the early stages of the restoration process. Also, the cascading lines can be far away from the initial physically damaged lines. More broadly, the early stages of the earthquake restoration process is affected by the extent of the cascading outages and is critical for search and rescue as well as restoring vital services. Also, we show that an investment plan focusing more heavily on outages in the first 3 days after the earthquake yields fewer outages in the first month, but more outages later in comparison with an investment plan focusing uniformly on outages over an entire 6-month restoration process.

CONGRATULATIONS on the article on public sector envy ('Demanding times,' National, July 20). It needed to be said. The once lowly workers of Canada have made it to the big [...]

Your tribute to our fallen soldiers ('Last letters from Kandahar,' National, Nov. 12) gives a small glimpse of their human decency, character and courage. My heart goes out to their […]

This paper develops a two-stage stochastic program and solution procedure to optimize the selection of seismic retrofit strategies to increase the resilience of electric power systems against earthquake hazards. The model explicitly considers the range of earthquake events that are possible and, for each, an approximation of the distribution of damage experienced. This is important because electric power systems are spatially distributed and so their performance is driven by the distribution of component damage. We test this solution procedure against the nonlinear integer solver in LINGO 13and apply the formulation and solution strategy to the Eastern Interconnection, where seismic hazard stems from the New Madrid seismic zone.

The Australian university sector has grown rapidly over the past two decades but the acceleration in numbers of students has far exceeded that of staff. Moreover numbers of staff in administration and support roles have grown more sharply that those of teaching staff. The key reason for the disproportionate growth in administrators is the way in which federal governments of both persuasions have introduced polices that require more and detailed accountability from universities. [ABSTRACT FROM AUTHOR]

Australian academics' response to the Changing Academic Profession (CAP) survey indicates that they are among the least satisfied academics in the world. This dissatisfaction has been expressed after two decades of rapid growth in the student body and structural changes in the academic workforce, particularly an expansion in the amount of teaching provided by casual staff. The growth in casual staff numbers is a factor which has simultaneously created a precariously employed but cheaper and more flexible workforce along with higher levels of stress among the full-time teachers responsible for managing and supervising casual teachers. The academic profession has an important role to play in creating a highly educated workforce for Australia and in generating export income by teaching international students. Careful attention needs to be paid to this situation especially in light of the need to replenish the ageing academic workforce. [ABSTRACT FROM AUTHOR]

Finnish universities are about to enter a period of radical change. This paper considers the reforms expected of a new Universities Act currently before parliament and a set of institutional mergers. When passed, the new act will provide universities with independent legal status, change their relationship with the government in several ways, affect university governance arrangements, and alter the relationship between staff and their university employers. Although these reforms will be radical for the university sector itself, many of the changes will be all but invisible to those outside the106 sector. The change that will be noticed is the creation of the new Aalto University through a merger between three existing institutions. The new university will be highly visible to all as it tries to meet the government's aspirations for it to become a world-class university. [ABSTRACT FROM AUTHOR]

We compare and test statistical estimates of failure propagation in data from versions of a probabilistic model of loading-dependent cascading failure and a power system blackout model of cascading transmission line overloads. The comparisons suggest mechanisms affecting failure propagation and are an initial step toward monitoring failure propagation from practical system data. Approximations to the probabilistic model describe the forms of probability distribution of cascade sizes.

We propose an analytically tractable model of loading-dependent cascading failure that captures some of the salient features of large blackouts of electric power transmission systems. This leads to a new application and derivation of the quasibinomial distribution and its generalization to a saturating form with an extended parameter range. The saturating quasibinomial distribution of the number of failed components has a power-law region at a critical loading and a significant probability of total failure at higher loadings.

We analyze a 15-year time series of North American electric power transmission system blackouts for evidence of self-organized criticality (SOC). The probability distribution functions of various measures of blackout size have a power tail and rescaled range analysis of the time series shows moderate long-time correlations. Moreover, the same analysis applied to a time series from a sandpile model known to be self-organized critical gives results of the same form. Thus, the blackout data seem consistent with SOC. A qualitative explanation of the complex dynamics observed in electric power system blackouts is suggested. [ABSTRACT FROM AUTHOR]

Academic staff and the academic research, teaching and scholarship they undertake are quite properly the prime focus in universities. However, in the modern university, these functions could not be carried out without the input of general (AKA "non-academic") staff. Staff who are not members of academe represent about 50% of all staff, and as a group are treated with antipathy by many academics. The terms "governance" and "administration" are misunderstood by many academics and used interchangeably when it suits them. This paper considers the binary divide between "academic" and "non-academic" staff, and considers the importance of terminology in ensuring that the total university can operate as efficiently as possible. [ABSTRACT FROM AUTHOR]

The release of Professor Linke's report on performance indicators in Australia refocussed the attention of institutional researchers on an analysis of student inputs/outputs in tertiary institutions. Data files routinely despatched to the Department of Employment, Education and Training by all institutions were used in this study. The study examines the student progress unit (SPU), defined as the ratio of load successfully completed by the student to the total assessed student load by the student. The study examines the determinants of student progress units for bachelor courses in Victorian higher education institutions in 1990, as reported in 1991. Variables examined include discipline group, sex, age, tertiary entrance score, attendance type and other social indicators. It explores the implications of findings of the study to student admission policies and identifies possible areas of future research.The results of this study were first reported at the 3rd Australasian Association for Institutional Research (AAIR) Forum, held in Auckland New Zealand during November 1992.

Several letters to the editor are presented in response to articles in previous issues including "Toronto stinks," in the July 27, 2009 issue and "Why do you leave the one you love?" by Mark Steyn and "Autistic license," both of which appeared in the July 20, 2009 issue.

Presents several letters to the editor in response to articles appearing in previous issues of "Maclean's." Response to the article "A time to die," in the September 5, 2005 issue; Comments about the article "Rumble on the Rock," in the September 5 issue; Discussion of the article "Lady-killers," in the September 5 issue; Others.

Several letters to the editor are presented concerning the prospects on railfreight flows, driver-only operated (DOO) trains, and the proposal for the electrification of the Valley lines from Cardiff, Wales.

Several letters to the editor are presented in response to the articles in the previous issues on the Supply Management journal including the intention of the Office of Government Commerce to ship and supply gas, posted on the April 27, 2006 issue, the failure of the government to met its recycling target, and in the idea of the quantity of effort to be exerted in the submission of a tender, by Paul Wright in the May 11, 2006 issue.

Presents letters to the editor in response to articles in previous issues including "Buyers Beware," in the September 22, 2005 issue, "Viewpoint," in the September 22, 2005 issue, "Benefits of Embracing CSR," in the October 6, 2005 issue, "Col Tim Collin's Contribution to CIPS Premier Conference," in the October 6, 2005 issue and "Wembley Construction Project," in the October 6, 2005 issue.

Offers cost-cutting tips to electricity and gas purchasers in Great Britain. Aim of the New Electricity Trading Arrangements to encourage a competitive market in wholesale electricity; Increase in gas price; Monitoring of the energy market.

The article reviews the 2015 issue of the periodical "Australian Universities' Review."

The article reviews the journal "Australian Universities' Review" or AUR.

A letter to the editor is presented which discusses the workings for the West Highland Railway in Great Britain.

A letter to the editor is presented in response to an article in the July 20, 2006 issue about the Chartered Institute of Purchasing and Supply in Great Britain.

Comments on the slow progress made by successive Australian governments to improve university access for young people from disadvantaged backgrounds. Proportion of university students from low socioeconomic backgrounds; Reasons behind the lack of progress; Contribution of the country's educational financial support system to the situation.