Operational strategies for offshore wind turbines to mitigate failure rate uncertainty on operational costs and revenue

Several operational strategies for offshore wind farms have been established and explored in order to improve understanding of operational costs with a focus on heavy lift vessel strategies. Additionally, an investigation into the uncertainty surrounding failure behaviour has been performed identifying the robustness of different strategies. Four operational strategies were considered: fix on fail, batch repair, annual charter and purchase. A range of failure rates have been explored identifying the key cost drivers and under which circumstances an operator would choose to adopt them. When failures are low, the fix on fail and batch strategies perform best and allow flexibility of operating strategy. When failures are high, purchase becomes optimal and is least sensitive to increasing failure rate. Late life failure distributions based on mechanical and electrical components behaviour have been explored. Increased operating costs because of wear-out failures have been quantified. An increase in minor failures principally increase lost revenue costs and can be mitigated by deploying increased maintenance resources. An increase in larger failures primarily increases vessel and repair costs. Adopting a purchase strategy can negate the vessel cost increase; however, significant cost increases are still observed. Maintenance actions requiring the use of heavy lift vessels, currently drive train components and blades are identified as critical for proactive maintenance to minimise overall maintenance costs

A study of project planning on Libyan construction projects

Construction projects are regularly faced by scheduling problems causing the projects to finish beyond their predetermined due date; this is a global phenomenon. The main purpose of this study is to consider the problems associated with project planning generally, with specific reference to construction projects in Libya. This study is unique in two respects. First, despite the recent high volume of infrastructure work in the country, there have been few investigations into construction delays in Libya. Secondly, earlier studies have considered the causes or the effects of project delays, whereas the present aim is to evaluate the potential of applying a planning and scheduling technique that is entirely novel in the Libyan context. The paper reports the results of Phase I of this research

Executive functioning affects health behaviour in older people too

Peer reviewedPublisher PD

Better Barking for ABS: Reform Proposals for the Asset-Backed Securities Market

The market for asset-backed securities (ABS) – financial instruments backed by underlying assets such as mortgages – suffered a major setback in 2007, as a cascade of downgrades and defaults brought turmoil to credit markets and the world economy. Authorities in the United States have since proposed sweeping changes to the ABS market. The Canadian Securities Administrators, representing provincial securities commissions, recently released a discussion paper proposing similar reforms, which would require: (i) sharply enhanced transparency in ABS structures, (ii) CEO certification of the adequacy of such structures, and (iii) disclosure of previous asset repurchases by the securities’ sponsor.Financial Services, asset-backed securities (ABS), credit markets

Analysis of offshore wind turbine operation & maintenance using a novel time domain meteo-ocean modeling approach

This paper presents a novel approach to repair modeling using a time domain Auto-Regressive model to represent meteo-ocean site conditions. The short term hourly correlations, medium term access windows of periods up to days and the annual distibution of site data are captured. In addition, seasonality is included. Correlation observed between wind and wave site can be incorporated if simultaneous data exists. Using this approach a time series for both significant wave height and mean wind speed is described. This allows MTTR to be implemented within the reliability simulation as a variable process, dependent on significant wave height. This approach automatically captures site characteristics including seasonality and allows for complex analysis using time dependent constaints such as working patterns to be implemented. A simple cost model for lost revenues determined by the concurrent simulated wind speed is also presented. A preliminary investigation of the influence of component reliability and access thresholds at various existing sites on availability is presented demonstrating the abiltiy of the modeling approach to offer new insights into offshore wind turbine operation and maintenance

Identification of Cirrus over Wausau during the 1986 FIRE IFO from ground-based radiometer data

The potential of using irradiation data to indicate episodes of cirrus cloudiness during the daylight hours is explored. Thresholds separating cirrus from other clouds and clear skies are determined using four days of irradiation data, hourly weather observations, sky photographs, sky video, and occasional lidar observations. Data were gathered during the First International Satellite Cloud Climatology Program (ISCCP) Regional Experiment (FIRE) Intensive Field Observations (IFO) cirrus project. Thresholds are tested using data from the remaining 17 days of the IFO. Cirrus episodes are defined as intervals when the sky cover is primarily cirrus. Measurements of incoming shortwave and near infrared full hemispheric and diffuse irradiation, and atmospheric infrared irradiation were made at Wausau, Wisconsin Municipal Airport. Data were collected between October 13 and November 2, 1986 and are one minute averages of ten second samples. Data from October 23 and from October 27 to 29 were used for threshold determination. Using weather observations, lidar output, photographs and video, sky conditions were grouped into three categories: noncirrus cloudy, cirrus, and clear. Irradiation data from all periods falling under each of the sky categories were then examined and thresholds denoting a change from one sky category to another were determined. Variables with only a small amount of overlap between sky categories were selected as key indicators

The Canadian ABS Market: Where Do We Go From Here?

The asset-backed securities (ABS) market suffered a major setback during the financial crisis that began in 2007. Its role in the broader market collapse has been well documented, but the need to restore a healthy ABS market is equally clear. Indeed, North American policymakers have readily acknowledged that this market must play a major role in the global economic recovery and policymakers have recently moved beyond addressing the urgency of restarting the ABS market to considering its reform. An analysis of current reform proposals guides suggestions for a policy approach that reflects Canadian market realities. Specifically, it would be prudent in the Canadian context to impose new disclosure requirements for all public market medium-term note issuance.Financial Services, asset-backed securities (ABS), ABS market reforms, Canadian ABS market, global economic recovery

Agricultural Policy Reform and Industry Adjustment in Australia and New Zealand

Some sectors of Australian and New Zealand farming have been heavily assisted in the past. New Zealand underwent an economy-wide deregulation in the mid-to-late 980s that included abrupt removal of practically all agricultural assistance. Policy reform in Australia has been more gradual and is industry focused, but in some cases substantial industry assistance has been withdrawn. Deregulation of the Australian dairy industry, and that of the sheep and beef sector in New Zealand, are discussed as case studies of these deregulations. Conclusions are drawn from these experiences, a major one being that previously-assisted farmers can successfully make the transition to market-driven agriculture.agricultural adjustment, policy reform, Australia, New Zealand, Agricultural and Food Policy,

Education in Pediatrics in US Colleges and Schools of Pharmacy

Objective. To determine the extent to which pediatrics is taught at US doctor of pharmacy (PharmD) programs and to characterize what is being taught and how. Methods. A 40-question online survey instrument was sent to accredited and candidate-status US PharmD programs. Results. Of 86 participating programs (67.2% response rate), 81 (94.2%) indicated that pediatric topics were included in their required classroom curricula (mean, 21.9 contact hours). A pediatric elective course was offered by 61.0% of programs (mean, 25.9 contact hours). Advanced pharmacy practice experiences (APPEs) in pediatrics were offered by 97.4% of programs, with an average of 27 students per program completing this practice experience annually. Conclusions. Almost all responding programs incorporated pediatrics in their required curricula. Pediatric elective courses provided an adequate mean number of contact hours, but 39.0% of programs did not offer an elective course. One-fifth of students completed a pediatric APPE prior to graduation. Continued expansion of pediatric-focused classroom and experiential curricula across US PharmD programs is recommended

New mobilities across the lifecourse: a framework for analysing demographically-linked drivers of migration

Migration, along with fertility and mortality, is one of the fundamental drivers of population change. Taking the lifecourse as the central concern, the authors set out a theoretical framework and define some key research questions for a programme of research that explores how the linked lives of mobile people are situated in time-space within the economic, social and cultural structures of contemporary society. Drawing on methodologically innovative techniques, these perspectives can offer conceptually significant and policy relevant insights into the changing nature and meanings of migration across the lifecourse