bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intake ground vortex and computational modelling of foreign object ingestion
Authors: MacManus D.G. , Slaby M. 
Published: February 2016

AbstractWhen an aero-engine is operating on the ground the formation of a potent inlet ground vortex can arise which has the ability to ingest foreign object debris. The ingestion of foreign objects can cause notable damage to engine components as well as overall performance degradation. The assessment of foreign object ingestion has been conducted using a combination of computational fluid dynamics, analytical modelling and an Euler-Lagrange uncoupled discrete phase particle tracking method. The flow fields for a full-scale aero-engine have been simulated for a range of ground clearances and intake velocity ratios under crosswind conditions. The sensitivity of the debris ingestion thresholds and characteristics to particle size and material density has been evaluated. The characteristics of the ingestion location within the intake are also considered for a range of operating conditions and particle parameters.
Autonomous obstacle avoidance for fixed-wing unmanned aerial vehicles
Authors: de Ruiter A. H. J. , Owlia S. 
Published: February 2016

AbstractThis paper investigates a method for autonomous obstacle avoidance for fixed-wing unmanned aerial vehicles (UAVs), utilising potential fluid flow theory. The obstacle avoidance algorithm needs only compute the instantaneous local potential velocity vector, which is passed to the flight control laws as a direction command. The approach is reactive, and can readily accommodate real-time changes in obstacle information. UAV manoeuvring constraints on turning or pull-up radii, are accounted for by approximating obstacles by bounding rectangles, with wedges added to their front and back to shape the resulting fluid pathlines. It is shown that the resulting potential flow velocity field is completely determined by the obstacle field geometry, allowing one to determine a non-dimensional relationship between obstacle added wedge-length and the corresponding minimum pathline radius of curvature, which can then be readily scaled in on-board implementation. The efficacy of the proposed approach has been demonstrated numerically with an Aerosonde UAV model.
Simulation and system identification of helicopter dynamics using support vector regression
Authors: Manso S. 
Published: February 2016

AbstractThis paper provides an overview of techniques developed for the application of support vector regression in the domain of simulation and system identification of helicopter dynamics. A generic high fidelity FLIGHTLAB helicopter model is used to train and validate a number of pitch response SVR models. These models are then trained using flight data from a Sikorsky Seahawk helicopter. The SVR simulation results show significant promise in the ability to represent aspects of a helicopter’s dynamics at a high fidelity. To achieve this, it is important to provide the SVR kernel with knowledge of past inputs that encompass the delay characteristics of the helicopter dynamic system. In this case, the use of nonlinear auto regressive eXogenous input network architecture achieves this goal. Good performance was achieved using input data that encompassed between 300 to 500ms worth of historic response.
CFD simulation of flapped rotors
Authors: Dehaeze F. , Baverstock K. D. , Barakos G. N. 
Published: February 2016

AbstractThe use of active trailing edge flaps on rotors may lead to performance benefits as well as noise and vibration reduction. In this work, computational fluid dynamics, using the HMB2 solver, is used to assess the effect of the trailing edge flaps on the whole flight domain of a modern main rotor. Starting from a baseline blade design, multiple techniques are demonstrated. The flap is first assessed using 2D pitching aerofoil simulations, followed by dMdt simulations, that account for the simultaneous variations of pitch and Mach around the azimuth. It was shown that enhanced lift was obtained while inspection of the moment coefficient showed negative damping for the flap for a limited set of conditions. Due to the 2D formulation, dMdt computations are fast to perform and can be used to inform codes predicting the rotor performance. The flap was then assessed in hover, and only allowed for limited improvement in blade performance at high thrust. In forward flight, the flap was actuated at a frequency of 1 per revolution, and was found to have a strong effect on the loads on the retreating side. The effect on the moments was even stronger. The flight envelope of the blade was explored, and clean and flapped cases were compared. The most noticeable changes occur at high and medium thrust. The CFD method was found to be efficient and robust, without any substantial penalties in CPU time, due to the flap modelling, over the tested conditions.
Design and construction of aeroelastic wind tunnel models
Authors: Stenfelt G. , Ringertz U. 
Published: February 2016

AbstractThe design and building of accurately scaled aeroelastic wind-tunnel models is difficult, time consuming and very costly. With the increasing usefulness of computational methods for predicting aeroelastic phenomena, few complex models have been built in recent years. New fighter aircraft projects are also becoming more and more scarce, and transport aircraft have essentially the same configuration since half a decade. This also significantly reduces the need for aeroelastic wind-tunnel models. However, there still is an interest in the results from aeroelastic testing. In some cases new and radical configurations may warrant wind-tunnel testing and in other cases complex phenomena arising in fight testing may need carefully performed experiments to resolve problems. However, there is definitely a trend towards building models and performing testing in the support of the development of computational methods.The developments in computer technology do not only improve the computational methods for aeroelasticity. Modern Computer Aided Design and Manufacturing techniques can significantly improve the quality and efficiency of the design and build process for aeroelastic models. There have also been some recent improvements in measurement techniques which have proven very useful for testing of aeroelastic wind-tunnel models. The paper will present some new design and build techniques developed for the manufacturing of a large scale wind-tunnel model of a canard delta wing fighter aircraft configuration. In the build process fiber-reinforced composites will be used, hence, challenges and possible solutions concerning the ability to produce a model with well defined material properties and fiber angles will be discussed. Further challenges arise when both measurement equipment and adjustable control surfaces should be attached inside the model using techniques that are possible to describe with computational methods. In addition, equipment, such as pressure taps, and control surface mechanics need to fit and function in a flexible structure. As a result, the above requirements will lead to necessary compromises in the design, hence, the paper will present the choices taken during the build process and for which reasons. The use of an optical positioning measurement system will also be discussed for both the validation of model properties and non-contact measurement of model deformations during wind-tunnel testing.
Trace fossils and tropical karst
Authors: DONOVAN STEPHEN K. 
Published: February 2016

AbstractTwo crinoid pluricolumnals from Permian rocks of Timor show similar patterns of external pitting. Platycrinitid sp. preserves circular, parabolic pits that do not cross-cut between columnals, some have raised rims and at least one columnal shows a growth deformity. These pits are interpreted as the trace fossil Oichnus paraboloides Bromley. Crinoid sp. indet. has particularly dense pits cross-cutting columnals on one side of the pluricolumnal only and extending onto the contiguous limestone; it is a Holocene microkarstic solution feature. Care must be taken to separate true bioerosive trace fossils from modern microkarstic features in limestones in the tropics.
Lower Wenlock black shales in the northern Holy Cross Mountains, Poland: sedimentary and geochemical controls on the Ireviken Event in a deep marine setting
Authors: SMOLAREK JUSTYNA , TRELA WIESŁAW , BOND DAVID P. G. , MARYNOWSKI LESZEK 
Published: February 2016

AbstractThe stratigraphic variability and geochemistry of Llandovery/Wenlock (L/W) Series boundary sediments in Poland reveals that hemipelagic sedimentation under an anoxic/euxinic water column was interrupted by low-density bottom currents or detached diluted turbid layers that resulted in intermittent seafloor oxygenation. Total organic carbon values and inorganic proxies throughout the Wilków 1 borehole section suggest variable redox conditions. U/Mo ratios > 1 throughout much of the Aeronian and Telychian stages, together with an absence of pyrite framboids, suggest oxygenated conditions prevailed. However, elevated total organic carbon near the Aeronian/Telychian boundary, together with increased U/Th and V/(V + Ni) ratios and populations of small pyrite framboids are consistent with the development of dysoxic/anoxic conditions at that time. U/Th, V/Cr and V/(V + Ni) ratios, as well as Uauthigand Mo concentrations, suggest that during the Ireviken black shale deposition, bottom-water conditions deteriorated from oxic during Telychian time to mostly suboxic/anoxic immediately prior to the L/W boundary, before a brief reoxygenation at the end of the Ireviken black shale sedimentation in the Sheinwoodian Stage. Rapid fluctuations in U/Mo during the Ireviken Event are characteristic of fluctuating redox conditions that culminated in an anoxic/euxinic seafloor in Sheinwoodian time. Following Ireviken black shale deposition, conditions once again became oxygen deficient with the development of a euxinic zone in the water column. The Aeronian to Sheinwoodian deep-water redox history was unstable, and rapid fluctuations of the chemocline across the L/W Series boundary probably contributed to the Ireviken Event extinctions, which affected mainly pelagic and hemipelagic fauna.
The specificity of Pavlovian regulation is associated with recovery from depression
Authors: Huys Q. J. M. , Gölzer M. , Friedel E. , Heinz A. , Cools R. , Dayan P. , Dolan R. J. 
Published: February 2016

BackgroundChanges in reflexive emotional responses are hallmarks of depression, but how emotional reflexes make an impact on adaptive decision-making in depression has not been examined formally. Using a Pavlovian-instrumental transfer (PIT) task, we compared the influence of affectively valenced stimuli on decision-making in depression and generalized anxiety disorder compared with healthy controls; and related this to the longitudinal course of the illness.MethodA total of 40 subjects with a current DSM-IV-TR diagnosis of major depressive disorder, dysthymia, generalized anxiety disorder, or a combination thereof, and 40 matched healthy controls performed a PIT task that assesses how instrumental approach and withdrawal behaviours are influenced by appetitive and aversive Pavlovian conditioned stimuli (CSs). Patients were followed up after 4–6 months. Analyses focused on patients with depression alone (n= 25).ResultsIn healthy controls, Pavlovian CSs exerted action-specific effects, with appetitive CSs boosting active approach and aversive CSs active withdrawal. This action-specificity was absent in currently depressed subjects. Greater action-specificity in patients was associated with better recovery over the follow-up period.ConclusionsDepression is associated with an abnormal influence of emotional reactions on decision-making in a way that may predict recovery.
‘They really get you motivated’: Experiences of a life-first employment programme from the perspective of long-term unemployed Australians
Authors: WALKER RUTH , BROWN LYNSEY , MOSKOS MEGAN , ISHERWOOD LINDA , OSBORNE KATY , PATEL KATE , KING DEB 
Published: February 2016

AbstractLong-term unemployment can negatively impact health and well-being, and is a central focus of governments seeking to address poverty and social exclusion. Little is known about how individuals experience programmes aimed at addressing long-term unemployment and consequently the client-centred indicators of ‘success’. In-depth interviews were carried out with 31 long-term unemployed individuals engaged in a ‘life-first’ programme integrating vocational assistance with intensive personal strengths-based support. The participants in this programme faced multiple disadvantages including employment and educational barriers as well as a range of significant personal issues. They equated successful outcomes in the programme with receiving a wealth of psychosocial and practical assistance in addition to vocational support, and having a case manager who approached these issues as a whole. Findings suggest that, in order to provide the best chance of gaining and maintaining employment, programmes should address, in tandem, personal and vocational barriers facing those who are long-term unemployed.
Virginia Farmers' Soil Conservation Decisions: An Application of Tobit Analysis
Authors: Norris Patricia E. , Batie Sandra S. 
Published: February 2016

AbstractUsing data from a survey of farm operators in two Virginia counties, the authors analyze farmers' soil conservation decisions. Results indicate that financial factors, including income and debt, are the most important influences on the sample farmers' use of conservation practices. Additional factors such as perception of erosion, education level, off-farm employment, and tenancy also influence conservation expenditures. Factors influencing conservation tillage acreage differ from those influencing expenditures for other conservation practices. In particular, age and race of the operator and on-farm erosion potential are significantly related to the use of conservation tillage but not other practices. These results are discussed in terms of their implications for conservation programs.
Incidence of West Nile virus infection in the Dallas–Fort Worth metropolitan area during the 2012 epidemic
Authors: WILLIAMSON P. C. , CUSTER B. , BIGGERSTAFF B. J. , LANCIOTTI R. S. , SAYERS M. H. , EASON S. J. , DIXON M. R. , WINKELMAN V. , LANTERI M. C. , PETERSEN L. R. , BUSCH M. P. 
Published: February 2016

SUMMARYThe 2012 West Nile virus (WNV) epidemic was the largest since 2003 and the North Texas region was the most heavily impacted. We conducted a serosurvey of blood donors from four counties in the Dallas–Fort Worth area to characterize the epidemic. Blood donor specimens collected in November 2012 were tested for WNV-specific antibodies. Donors positive for WNV-specific IgG, IgM, and neutralizing antibodies were considered to have been infected in 2012. This number was adjusted using a multi-step process that accounted for timing of IgM seroreversion determined from previous longitudinal studies of WNV-infected donors. Of 4971 donations screened, 139 (2·8%) were confirmed WNV IgG positive, and 69 (1·4%) had IgM indicating infection in 2012. After adjusting for timing of sampling and potential seroreversion, we estimated that 1·8% [95% confidence interval (CI) 1·5–2·2] of the adult population in the Dallas–Fort Worth area were infected during 2012. The resulting overall estimate for the ratio of infections to reported WNV neuroinvasive disease (WNND) cases was 238:1 (95% CI 192–290), with significantly increased risk of WNND in older age groups. These findings were very similar to previous estimates of infections per WNND case, indicating no change in virulence as WNV evolved into an endemic infection in the United States.
Multimodality cardiac imaging in Turner syndrome
Authors: Mortensen Kristian H. , Gopalan Deepa , Nørgaard Bjarne L. , Andersen Niels H. , Gravholt Claus H. 
Published: February 2016

AbstractCongenital and acquired cardiovascular diseases contribute significantly to the threefold elevated risk of premature death in Turner syndrome. A multitude of cardiovascular anomalies and disorders, many of which deleteriously impact morbidity and mortality, is frequently left undetected and untreated because of poor adherence to screening programmes and complex clinical presentations. Imaging is essential for timely and effective primary and secondary disease prophylaxis that may alleviate the severe impact of cardiovascular disease in Turner syndrome. This review illustrates how cardiovascular disease in Turner syndrome manifests in a complex manner that ranges in severity from incidental findings to potentially fatal anomalies. Recommendations regarding the use of imaging for screening and surveillance of cardiovascular disease in Turner syndrome are made, emphasising the key role of non-invasive and invasive cardiovascular imaging to the management of all patients with Turner syndrome.
Analysis of Patient Load Data From the 2002 FIFA World Cup Korea/Japan
Authors: Morimura Naoto , Katsumi Atsushi , Koido Yuichi , Sugimoto Katsuhiko , Fuse Akira , Asai Yasfumi , Ishii Noboru , Ishihara Toru , Fujii Chiho , Sugiyama Mitsugi , Henmi Hiroshi , Yamamoto Yasuhiro 
Published: February 2016

AbstractIntroduction:Past history of mass casualties related to international football games brought the importance of practical planning, preparedness, simulation training, and analysis of potential patient presentations to the forefront of emergency research.Methods:The Japanese Ministry of Health, Labor, and Welfare established the Health Research Team (HRT-MHLW) for the 2002 FIFA World Cup game (FIFAWC). The HRT-MHLW collected patient data related to the games and analyzed the related factors regarding patient presentations.Results:A total of 1,661 patients presented for evaluation and care from all 32 games in Japan. The patient presentation rate per 1,000 spectators per game was 1.21 and the transport-to-hospital rate was 0.05. The step-wise regression analysis identified that the patient presentations rate increased where access was difficult. As the number of total spectators increased, the patient presentation rate decreased. (p <0.0001, r = 0.823, r2 = 0.677).Conclusion:In order to develop mass-gathering medical-care plans in accordance with the types and sizes of mass gatherings, it is necessary to collect data and examine risk factors for patient presentations for a variety of events.
Prehospital Rapid Sequence Intubation in an Emergency Medical Services System with Two Advanced Life Support Providers
Authors: Merlin Mark A. , Safdar Huma , Calabrese Susan , Lewinsky Alex , Manfre Joseph , Pelt Stephen Van , Marques-Baptista Andreia 
Published: February 2016

AbstractObjective:A rapid sequence intubation (RSI) method was introduced to a university-based emergency medical services (EMS) system. This is a report of the initial experience with the first 50 patients in a unique, two-tiered, two-advanced life support (ALS) providers system.Methods:The data were evaluated prospectively after an extensive RSI training period, consisting of didactic information and skills performance. Fifty consecutive patient records that documented the procedure were abstracted. Data abstracted included end-tidal CO2, heart rate, blood pressure, and pulse oximetry at various time intervals. Intubation success rates and number of attempts were documented. The consistency of proper documentation also was noted on patient care records.Results:No differences were noted in heart rate prior to RSI and one and five minutes after the RSI procedure was begun. No differences in blood pressure at one and five minutes were noted. Statistically significant improvements were found in pulse oximetry comparing prior to RSI and one minute after (p < 0.001; 95% CI = 3.15–11.41) as well as prior to RSI and five minutes after RSI was started (p < 0.0002; 95% CI = 4.60–13.33). No differences were observed in end-tidal CO2 at one and five minutes. Overall intubation success rate was 96%, with 82% on first attempt and 92% on two or less attempts. Documentation for individual vitals was consistently <75%.Conclusions:Patients had no significant worsening of vital signs during the RSI procedure and mild improvement in pulse oximetry. Intubation success rates were consistent with national averages. Proper documentation was lacking in more than one quarter of the charts. These data add to a body of literature that raises further concerns regarding prehospital RSI.
International Consensus on Key Concepts and Data Definitions for Mass-gathering Health: Process and Progress
Authors: Turris Sheila A. , Steenkamp Malinda , Lund Adam , Hutton Alison , Ranse Jamie , Bowles Ron , Arbuthnott Katherine , Anikeeva Olga , Arbon Paul 
Published: February 2016

AbstractMass gatherings (MGs) occur worldwide on any given day, yet mass-gathering health (MGH) is a relatively new field of scientific inquiry. As the science underpinning the study of MGH continues to develop, there will be increasing opportunities to improve health and safety of those attending events. The emerging body of MG literature demonstrates considerable variation in the collection and reporting of data. This complicates comparison across settings and limits the value and utility of these reported data. Standardization of data points and/or reporting in relation to events would aid in creating a robust evidence base from which governments, researchers, clinicians, and event planners could benefit. Moving towards international consensus on any topic is a complex undertaking. This report describes a collaborative initiative to develop consensus on key concepts and data definitions for a MGH “Minimum Data Set.” This report makes transparent the process undertaken, demonstrates a pragmatic way of managing international collaboration, and proposes a number of steps for progressing international consensus. The process included correspondence through a journal, face-to-face meetings at a conference, then a four-day working meeting; virtual meetings over a two-year period supported by online project management tools; consultation with an international group of MGH researchers via an online Delphi process; and a workshop delivered at the 19thWorld Congress on Disaster and Emergency Medicine held in Cape Town, South Africa in April 2015. This resulted in an agreement by workshop participants that there is a need for international consensus on key concepts and data definitions.TurrisSA,SteenkampM,LundA,HuttonA,RanseJ,BowlesR,ArbuthnottK,AnikeevaO,ArbonP.International consensus on key concepts and data definitions for mass-gathering health: process and progress.Prehosp Disaster Med.2016;31(2):220–223.
A Nonparametric Analysis of Efficiency for a Sample of Kansas Beef Cow Farms
Authors: Featherstone Allen M. , Langemeier Michael R. , Ismet Mohammad 
Published: February 2016

AbstractCompetitive pressures in the cow-calf sector increased in 1995 because of a decline of 27% in calf prices. Technical, allocative, and scale efficiency measures were used to examine the competitiveness of a sample of Kansas beef cow farms. On average, the farms were 78% technically efficient, 81% allocatively efficient, and 95% scale efficient. Enterprise profitability was correlated positively with the efficiency measures. Inefficiency was related to herd size and degree of specialization. Producers should focus on using capital, feed, and labor more efficiently rather than increasing their size. Increased concentration of the cow-calf sector will not result in large cost savings given the current technology.