Cranfield University is a British postgraduate and research-based university with two campuses. The main campus is at Cranfield, Bedfordshire and the second is the Defence Academy of the United Kingdom at Shrivenham, Oxfordshire. The main campus is unique in the United Kingdom for having an operational airport next to the main campus. The airport facilities are used by Cranfield University's own aircraft in the course of aerospace teaching and research. Wikipedia.
Sullman M.J.M.,Cranfield University
Transportation Research Part F: Traffic Psychology and Behaviour | Year: 2012
This study set out to investigate the proportion of UK drivers who engage in some form of distracting behaviour whilst driving. Data were collected by roadside observation in six urban centres in the South of England. The observations took place on randomly selected roads at three different time periods during two consecutive Tuesdays. The data revealed that 14.4% of the 7168 drivers observed were found to be engaged in a distracting activity. The most frequently observed distraction was talking to a passenger, followed by smoking and using a mobile phone. Younger drivers were significantly more likely to be distracted in general and by talking to passengers, while older drivers were less likely to be distracted by adjusting controls or using a mobile phone. © 2012 Elsevier Ltd. All rights reserved.
Rickson R.J.,Cranfield University
Science of the Total Environment | Year: 2014
The detrimental impact of sediment and associated pollutants on water quality is widely acknowledged, with many watercourses in the UK failing to meet the standard of 'good ecological status'. Catchment sediment budgets show that hill slope erosion processes can be significant sources of waterborne sediment, with rates of erosion likely to increase given predicted future weather patterns. However, linking on-site erosion rates with off-site impacts is complicated because of the limited data on soil erosion rates in the UK and the dynamic nature of the source-pathway-receptor continuum over space and time. Even so, soil erosion control measures are designed to reduce sediment production (source) and mobilisation/transport (pathway) on hill slopes, with consequent mitigation of pollution incidents in watercourses (receptors). The purpose of this paper is to review the scientific evidence of the effectiveness of erosion control measures used in the UK to reduce sediment loads of hill slope origin in watercourses. Although over 73 soil erosion mitigation measures have been identified from the literature, empirical data on erosion control effectiveness are limited. Baseline comparisons for the 18 measures where data do exist reveal erosion control effectiveness is highly variable over time and between study locations. Given the limitations of the evidence base in terms of geographical coverage and duration of monitoring, performance of the different measures cannot be extrapolated to other areas.This uncertainty in effectiveness has implications for implementing erosion/sediment risk reduction policies, where quantified targets are stipulated, as is the case in the EU Freshwater Fish and draft Soil Framework Directives. Also, demonstrating technical effectiveness of erosion control measures alone will not encourage uptake by land managers: quantifying the costs and benefits of adopting erosion mitigation is equally important, but these are uncertain and difficult to express in monetary terms. © 2013 Elsevier B.V.
Gohardani O.,Cranfield University
Progress in Aerospace Sciences | Year: 2011
High speed of aero vehicles including commercial and military aircraft, missiles, unmanned air vehicles, as well as conceptual aircraft of the future are imposing larger restrictions on the materials of these vehicles and highlight the importance of adequate quantification of material behavior and performance during different flight conditions. Erosion due to weather conditions and other present particles such as hydrometeors; rain, hail and ice, as well as sand, volcanic ash and dust resulting from residues in the atmosphere are eminent as hazardous on the structure of a flying vehicle and may adversely influence the lifecycle of the structure. This study outlines an extensive review of research efforts on erosion in aviation and provides a basis for comparison between different apparatus simulating rain erosion and their usage within the aerospace industry. The significant aspects of erosion testing and future prospects for erosion impact are further addressed for forthcoming generations of flying vehicles. © 2011 Elsevier Ltd. All Rights Reserved.
Shafiee M.,Cranfield University
Renewable Energy | Year: 2015
Logistics and supply chain management of maintenance is a very critical task in the offshore wind energy industry. A failure to deliver proper maintenance services may adversely affect the wind farm availability and thereby reducing power output as well as profitability. The organization of maintenance logistics for offshore wind farms has received a reasonable attention in the literature to date. The purpose of this article is to review the state-of-the-art of maintenance logistics in offshore wind energy. It proposes a classification scheme involving three echelons of strategic, tactical and operational decision-making. The strategic echelon deals with decisions regarding wind farm design for reliability, location and capacity of maintenance accommodations, selection of wind farm maintenance strategy, and outsourcing the repair services. The tactical echelon embraces spare parts inventory management, maintenance support organization, and all decisions regarding purchase or lease of maintenance resources. The operational echelon includes scheduling of maintenance tasks, routing of vessels, and measuring the maintenance performance. Our findings indicate that the strategic decisions of maintenance logistics have received the most attention in the literature, followed by the tactical and operational decisions. Also, three categories of selection of maintenance strategy, maintenance support organization and scheduling of maintenance tasks are the most addressed areas of research. © 2014 Elsevier Ltd.
Silson P.M.G.,Cranfield University
IEEE Transactions on Instrumentation and Measurement | Year: 2011
This paper presents a novel estimation method for fast initial coarse alignment of a ship's strapdown inertial attitude reference system using only inertial measurement unit (IMU) measurements for quasi-static alignment and IMU measurements with GPS aiding for moving-base alignment. Unlike several current techniques, the presented estimation method is effective with any initial attitude error. The estimator is based on the decomposition of the attitude quaternion into separate Earth motion, inertial rate, and alignment quaternions. The alignment quaternion is estimated using a minimum variance fit between loci of body- and navigation-frame velocity vectors using solutions to Wahba's problem. One set of vectors is derived from time integrals of measured vehicle motions, and the second set is derived from Earth motion and GPS data (when moving). For the case of quasi-static alignment, an algebraic expression for the covariance of the attitude estimate as a function of the variance of navigation-frame velocity disturbances is developed. It is shown that, by averaging and interleaving the velocity vectors, the resulting attitude estimate is improved over sequential sampling techniques. It is further shown, for a maneuvering vessel, that a continuous estimate of the attitude error covariance can be generated from the IMU data. This latter feature allows direct initialization of a follow-on fine-alignment stochastic estimator's covariance matrix. Results are presented for quasi-static alignment using inertial sensors only and for full in-motion alignment using navigation-frame GPS velocity and position aiding. © 2011 IEEE.