185 research outputs found
Uncertainties in the design of support structures and foundations for offshore wind turbines
Offshore wind industry has exponentially grown in the last years. Despite this growth, there are still many uncertainties in this field. This paper analyzes some current uncertainties in the offshore wind market, with the aim of going one step further in the development of this sector. To do this, some already identified uncertainties compromising offshore wind farm structural design have been identified and described in the paper. Examples of these identified uncertainties are the design of the transition piece and the difficulties for the soil properties characterization. Furthermore, this paper deals with other uncertainties not identified yet due to the limited experience in the sector. To do that, current and most used offshore wind standards and recommendations related to
the design of foundation and support structures (IEC 61400-1, 2005; IEC 61400-3, 2009; DNV-OS-J101, Design of Offshore Wind Turbine, 2013 and Rules and Guidelines Germanischer Lloyd, WindEnergie, 2005) have been analyzed. These new identified uncertainties are related to the lifetime and return period, loads combination, scour phenomenon and its protection, Morison e Froude Krilov and
diffraction regimes, wave theory, different scale and liquefaction. In fact, there are a lot of improvements to make in this field. Some of them are mentioned in this paper, but the future experience in the matter will make it possible to detect more issues to be solved and improved
The geopolitics of Boko Haram and Nigeria's ‘war on terror’
The April 2014 kidnapping of the schoolgirls at Chibok, north-eastern Nigeria, has meant that Boko Haram is now widely discussed by Western governments and in Western media. Yet within Nigeria the group has been well known for several years. Boko Haram's activities, or actions attributed to the group, have developed in a range of ways, many contradictory, including bombings, kidnappings of Europeans within Nigeria and neighbouring Cameroon, killing of medical personnel, and overtures for dialogue with the Federal Government. There are recurrent reports of links to Al Qaeda in the Islamic Maghreb, and in the past few years the United States has taken a much more active role in the region. Some of the wider geopolitical issues relate to the French-led intervention in Mali; a country to which Nigeria has also sent troops. This article tries to disentangle these different questions. It looks first at who Boko Haram are, and their history. It situates the group within the wider context of Nigerian politics, and to discuss the biopolitical and geopolitical elements of their operations and of the actions of the Nigerian security services and other actors towards them. It ends by relating what is happening within and beyond Nigeria to the wider context of the ‘war on terror’
Understanding and enhancing future infrastructure resiliency: a socio-ecological approach
The resilience of any system, human or natural, centres on its capacity to adapt its structure, but not necessarily its function, to a new configuration in response to long-term socio-ecological change. In the long term, therefore, enhancing resilience involves more than simply improving a system's ability to resist an immediate threat or to recover to a stable past state. However, despite the prevalence of adaptive notions of resilience in academic discourse, it is apparent that infrastructure planners and policies largely continue to struggle to comprehend longer-term system adaptation in their understanding of resilience. Instead, a short-term, stable system (STSS) perspective on resilience is prevalent. This paper seeks to identify and problematise this perspective, presenting research based on the development of a heuristic 'scenario-episode' tool to address, and challenge, it in the context of United Kingdom infrastructure resilience. The aim is to help resilience practitioners to understand better the capacities of future infrastructure systems to respond to natural, malicious threats
Field, capital and the policing habitus: nderstanding Bourdieu through The NYPD’s post-9/11 counterterrorism practices
This article extends existing Bourdieusian theory in criminology and
security literature through examining the practices of the New York City
Police Department in the post-9/11 counterterrorism field. This article
makes several original contributions. First, it explores the resilient nature
of the policing habitus, extending Bourdieusian criminological findings
that habitus are entrenched and difficult to change. Second, this article
examines the way the resilient habitus drives subordinate factions to
displace dominant factions in a field’s established social hierarchy
through boundary-pushing practices, a concept previously unexamined in
Bourdieusian criminology. Drawing on original documentary analysis, this
article uses the illustrative example of the NYPD’s post-9/11
counterterrorism practices, exploring how it sought to displace the
existing social structure by using its aggressive policing habitus and an
infusion of ‘War on Terror’ capital to challenge the dominant position of
the FBI in the post-9/11 counterterrorism field. The NYPD’s habitus
driven counterterrorism practices were novel and unprecedented,
creating strain with both the FBI and local communities
National Commission on Terrorist Attacks Upon the United States
Provides access to information about the Commission and data produced by the Commission in pursuit of its mission to prepare a full and complete account of the circumstances surrounding the September 11, 2001 terrorist attacks and to provide recommendations designed to guard against future attacks. Includes archived transcripts, videos of the public hearings held by the Commission, and full text of final report
Effectiveness of antioxidants in preventing oxidation of palm oil enriched with heme iron: A model for iron fortification in baked products
Bakery products such as biscuits, cookies, and pastries represent a good medium for iron fortification in food products, since they are consumed by a large proportion of the population at risk of developing iron deficiency anemia, mainly children. The drawback, however, is that iron fortification can promote oxidation. To assess the extent of this, palm oil added with heme iron and different antioxidants was used as a model for evaluating the oxidative stability of some bakery products, such as baked goods containing chocolate. The palm oil samples were heated at 220°C for 10 min to mimic the conditions found during a typical baking processing. The selected antioxidants were a free radical scavenger (tocopherol extract (TE), 0 and 500 mg/kg), an oxygen scavenger (ascorbyl palmitate (AP), 0 and 500 mg/kg), and a chelating agent (citric acid (CA), 0 and 300 mg/kg). These antioxidants were combined using a factorial design and were compared to a control sample, which was not supplemented with antioxidants. Primary (peroxide value and lipid hydroperoxide content) and secondary oxidation parameters (p-anisidine value, p-AnV) were monitored over a period of 200 days in storage at room temperature. The combination of AP and CA was the most effective treatment in delaying the onset of oxidation. TE was not effective in preventing oxidation. The p-AnV did not increase during the storage period, indicating that this oxidation marker was not suitable for monitoring oxidation in this model
Monograph on Terrorist Financing, Staff Report to the Commission (August 21, 2004)
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9/11 and Terrorist Travel, Staff Report of the National Commission on Terrorist Attacks Upon the United States (August 21, 2004)
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