bluuebunny/crossref_metadata_2025_split huggingface dataset:
A DATABASE OF NERC RADIOCARBON MEASUREMENTS DETERMINED BY ACCELERATOR MASS SPECTROMETRY
Authors: Garnett M H , Bryant C L , Freeman S P H T , Gulliver P , Ascough P L 
Published: March 2023

ABSTRACTRadiocarbon (14C) measurements undertaken by the NERC Radiocarbon Laboratory using accelerator mass spectrometry (AMS) are now freely available on a new online database. The data presented covers measurement of the wide range of sample types that are processed for research projects in the fields of Earth and environmental science, supported by the United Kingdom’s Natural Environment Research Council. Sample types within the database include organic remains, soils, sediments, carbonates, dissolved organic and inorganic carbon, and carbon dioxide. Currently, the database contains 14C data for over 2400 individual samples that were measured and reported between 2005 and 2013, but it is envisaged that this will expand considerably as more data are made available. Contextual information such as sampling location and associated publications are provided where available, and searches can be performed on sample location, sample type, project number, and publication code. This new database compliments an existing, publicly available database of measurements performed using radiometric methods by the laboratory which has recently been expanded to present over 2000 measurements. It is hoped that this archive will prove useful to workers in the community who would benefit from greater availability of measurements for particular locations or sample types, and for the purposes of performing meta-analyses, and/or synthesis of larger datasets.
Part I: For the nacelle at a steady incidence
Authors: Sheu M. J. , Hancock G. J. 
Published: March 2023

SummaryA simple nacelle comprising a thin cylindrical shell of uniform diameter enclosing an engine, idealised by an actuator disc, is analysed at incidence to a low speed uniform stream for various engine mass flow rates on the basis of a vortex lattice model.Loadings along the length of the nacelle are calculated, together with the overall normal force, the leading edge thrust on the nacelle nose, and the overall pitching moment. Most of the loading arises over the front part of the nacelle, which is well known. However, there is a significant contribution to the overall pitching moment from the nacelle nose for a nacelle, with engine, at incidence; this effect is absent from a through flow nacelle without an engine. Formulae for ∂CN/∂α and ∂CM/∂α as functions of mass flow rate are derived for a length/diameter ratio of 3:0.
Effect of wing nose shape on the flow in a wing/body junction
Authors: Mehta R. D. 
Published: March 2023

SummaryA powerful mechanism for the generation of secondary flow, which does not rely on viscous or turbulent stress, is lateral skewing of a shear layer such as that encountered by the body boundary layer in a wing/body junction. For a given entry shear, the characteristics of the secondary flow (a horse-shoe vortex) will depend on the wing nose shape. The effects of three wing nose shapes on the size, position and strength of the horse-shoe vortex have been studied in low-speed flow. As expected, the vortex size and strength increased with nose bluntness; quantitative data describing this effect are presented in this paper. The results include contours of streamwise velocity and secondary velocity plots from which vorticity contours and a non-dimensional circulation were derived. The results should be of use in wing design where this secondary flow needs to be controlled.
A sub-contractor’s viewpoint
Authors: Howard R. W. 
Published: March 2023

The management of civil aircraft airworthiness must embrace three requirements.1. To establish a working system which ensures that airworthiness is achieved.2. To demonstrate to the certification authorities that it has
been achieved and3. To ensure that airworthiness is maintained throughout the
life of the aircraft.The sub-contractor’s task has traditionally been one of carrying out appropriate analysis and testing and then to supply to the prime contractor (usually the aircraft constructor) the data on his equipment which is required to satisfy these three requirements. Subsequently he must support this, as necessary, with the operators until the end of the life of the aircraft.
The city helistop
Authors: Brown E. M. 
Published: March 2023

The large number of enquiries received by the BHAB show that there is a need for basic guidelines on this subject. These are given here but more detailed information is available from the Civil Aviation Authority, AS4.Any owner of a piece of ground may use it as a helicopter landing facility without any kind of permission, provided the following conditions are met:a.It is not in a congested area, as defined in Article 90 of the Air Navigation Order 1976, that is, any area which is substantially used for residential, industrial, commercial or recreational purposes.(Note: In this context, the CAA considers the term “substantial’ to mean 50% or more.)b.No structure is erected in connection with its use as a helicopter landing area, eg concrete landing pad, hangar,etc, other than a temporary structure such as a windsock.c.Its usage is confined to the private or business use of the owner, his employees or anyone specifically visiting him for social or business purposes.d.A pilot using the site will be able to conform with Rule 5 of the Rules of the Air and Air Traffic Control Regulations 1976.
Experimental determination of the aerodynamic characteristics of ski-jumpers
Authors: Ward-Smith A. J. , Clements D. 
Published: March 2023

SummaryThe aerodynamic pitching moment, lift and drag forces acting on a ski-jumper during the free flight and landing phases were measured using scaled models in a wind tunnel. Comparisons are made between those meaurements and observations of actual ski-jumps.It is shown that the high angles of incidence (typically α varies from 35° to 55°) adopted by ski-jumpers during free flight is determined by the need to prevent tumbling. Over this range of incidence angles, the opposing moments due to weight distribution and aerodynamic pressure distribution are approximately in equilibrium, and small out-of-balance moments can be accommodated by arm movements. The maximum lift/drag ratio on a ski-jumper in free flight occurs at α ≃ 25°. If it were possible to avoid tumbling at low incidence angles, maximum jump lengths would be achieved at α ≃ 8°.
Advances in manufacturing technology
Authors: Turner Frank 
Published: March 2023

In this presentation I will review the advances in manufacturing technology applied to the manufacture of large civil aero engines, but first I think we ought to look back and put these advances into some sort of historical perspective.Traditionally the level of automation in civil aero engine manufacture has been relatively low. However, the level of technology in the component and that applied to the individual manufacturing operations has been very high.Automation, from the start of the Industrial Revolution has been directed to the mass production of high volumes of relatively simple stable design components using conventional materials and production processes.
Direct and inverse integral calculation methods for three-dimensional turbulent boundary layers
Authors: Smith P. D. 
Published: March 2023

It is both a privilege and a pleasure to be asked to contribute to an edition of the Aeronautical Journal to celebrate Professor Alec Young's 70th birthday. He has been my mentor for nearly a quarter of a century.The subject of integral prediction methods for boundary layers is one with which Alec Young has long been associated. Starting with a method for laminar compressible flow he has guided the development of, amongst others, integral methods for compressible laminar flow with heat transfer, three-dimensional laminar flow, three-dimensional turbulent flow and flows with pressure gradients normal to the surface.This paper attempts to describe the integral methods for compressible turbulent boundary layers which are most widely used in aerodynamic design and to discuss the application of inverse integral methods to three-dimensional separated flows.
Airline flight departure procedures — choosing between noise abatement, minimum fuel consumption and minimum cost
Authors: Jones R. E. 
Published: March 2023

The advent of the commercial jet air liner, two decades ago, and growing public awareness of the noise of aircraft operations, led to the adoption by airlines of two distinct take-off departure procedures. A Standard Procedure for aircraft departures is usually recommended by the aircraft manufacturer, such that the air liner is operated in a safe and expeditious manner. A Noise Abatement Procedure was devised to reduce the noise impact of airline operations in the airport community environs. Generally, noise abatement procedures were thought to increase pilot work load and, therefore, reduce margins of safety, and increase fuel consumption.In the 1960s, when most of the air liners were powered by low by-pass ratio engines, the noise abatement procedure included a so called cut-back. This procedure included throttling back from take-off thrust (TOT) to less than climb thrust shortly after take-off (during cut-back) to benefit those communities living close to the airport. Subsequently climb thrust (MCLT) would be applied.
Flexible spacecraft attitude control using a simple P + D algorithm
Authors: Fenton J. , Gill K. F. 
Published: March 2023

Two philosophies for the attitude control of space vehicles with flexible appendages have appeared in the literature, these are:
(i)control of the rigid centre body to lie within some bounded region while the flexural vibrations are allowed to behave in an uncontrolled manner;(ii)control of all plant states to some finite value as time tends to infinity.The former method does not require flexural information and therefore avoids the on-board computational burden associated with state estimation, or the cost of additional instrumentation. However, attitude degradation has been observed and reported indicating a clear need to compensate for structural vibrations.
On the choice of axes systems for aircraft dynamic calculations
Authors: Hitch H. 
Published: March 2023

In the places in the UK where these things are discussed, there is a reconsideration of the pros and cons of the two axes systems commonly used for aircraft dynamic calculations.The first of these is a system fixed in the body and moving therefore with it: this system is referred to as ‘body axes’ and is used by the ‘stability and control’ specialists for assessing rigid aircraft behaviour.The second is a fixed inertial frame fixed in the earth and is used by the flutter specialists for assessing a variety of behaviours of the flexible aircraft. It is the purpose of this paper to point out the very simple correspondence between these two systems in the case of small perturbations from an equilibrium position of the rigid aircraft flying straight and level. The first section presents unpublished work from the Vickers Aircraft Company’s files done in 1952 which is confined to the symmetric motion at constant speed (i.e. with the phugoid suppressed).
Sophisticated aircraft structure developments — combat aeroplanes
Authors: Sellars R. J. , Terry G. 
Published: March 2023

Throughout its existence the organisation now known as British Aerospace, Warton Division has been primarily concerned with the design and manufacture of advanced combat aircraft. Often it is in this class of aircraft that the advantages of developments in structures and materials are first realised on a production basis.This paper briefly describes some of the currrent involvement of Warton structural engineers in material selection, technology demonstrators and future projects for the next generation of combat aircraft.
An assessment of the universal Strouhal number concepts for two-dimensional bluff bodies
Authors: Awbi H. B. 
Published: March 2023

SummaryThe ‘universal’ Strouhal number, SB, which was derived by Bearman using the Kronauer vortex stability criterion is presented for two-dimensional rectangular-section prisms of depth to width ratio, d/h, from 1 to 5, for a flat plate with and without splitter plates, for a circular cylinder with splitter plates and for a circular cylinder with two blowing slots to control its wake width. A value of SB close to Bearman's value of 0·181 is obtained for the prisms of small d/h, for the plate without a splitter plate, for the cylinder with small splitter plates and for the cylinder for low blowing rates. For the other cases, however, SB is found to vary within the range 0·137 to 0·208 which is an indication that the general application of this concept to two-dimensional bluff bodies is superficial.
An analytical study of the induced drag of canard-wing-tail aircraft configurations with various levels of static stability
Authors: Butler G. F. 
Published: March 2023

SummaryThe prospect of reducing the induced drag of an aircraft by using both a canard and tailplane for trimming is investigated and results are compared with those for conventional tail-aft and canard arrangements. It is concluded that improvements of approximately 20% in lift-drag ratio are theoretically possible at high lift coefficients by the use of an additional trimming surface.
Dynamics of a delayed population patch model with the dispersion matrix incorporating population loss
Authors: Huang Dan , Chen Shanshan 
Published: March 2023

AbstractIn this paper, we consider a general single population model with delay and patch structure, which could model the population loss during the dispersal. It is shown that the model admits a unique positive equilibrium when the dispersal rate is smaller than a critical value. The stability of the positive equilibrium and associated Hopf bifurcation are investigated when the dispersal rate is small or near the critical value. Moreover, we show the effect of network topology on Hopf bifurcation values for a delayed logistic population model.
Learning second language morphosyntax in dialogue under explicit and implicit conditions: An experimental study with advanced adult learners of German
Authors: Koch Eva M. , de Vos Johanna F. , Housen Alex , Godfroid Aline , Lemhöfer Kristin 
Published: March 2023

AbstractWe investigate the role of awareness in learning non-salient grammar features in a second language during oral interaction. We conducted a learning experiment during which forty-eight adult Dutch-speaking advanced learners of German and a native German-speaking experimenter engaged in a scripted oral dialogue game. The experimenter and learner in turn produced sentences based on pictures eliciting German strong verbs with stem-vowel alternations, a morphosyntactic feature that represents a persistent learning difficulty. While learners in the implicit condition were merely instructed to focus on sentence meaning, learners in the explicit condition were encouraged to also pay attention to and learn from the target structure in the experimenter's input. Although the explicit group achieved higher accuracy scores overall, both groups had similar (absolute) learning gains, showing that oral input provided during interactive exchanges can lead to substantial learning not only under explicit, learning-targeted conditions, but also without an explicit directive to learn.
FIRST-ORDER RELEVANT REASONERS IN CLASSICAL WORLDS
Authors: FERENZ NICHOLAS 
Published: March 2023

AbstractSedlár and Vigiani [18] have developed an approach to propositional epistemic logics wherein (i) an agent’s beliefs are closed under relevant implication and (ii) the agent is located in a classical possible world (i.e., the non-modal fragment is classical). Here I construct first-order extensions of these logics using the non-Tarskian interpretation of the quantifiers introduced by Mares and Goldblatt [12], and later extended to quantified modal relevant logics by Ferenz [6]. Modular soundness and completeness are proved for constant domain semantics, using non-general frames with Mares–Goldblatt truth conditions. I further detail the relation between the demand that classical possible worlds have Tarskian truth conditions and incompleteness results in quantified relevant logics.
The Influence of Psychosocial Factors according to Gender and Age in Hospital Care Workers
Authors: Cañavate Germán , Meneghel Isabella , Salanova Marisa 
Published: March 2023

Abstract
Even though psychosocial risks can affect the entire working population regardless of demographic variables, multiple publications claim that women are more exposed to psychosocial risks and that psychosocial risks affect people in a different way, depending on their age. This study aims to investigate demographic differences (i.e., sex and age) in health care workers, with an aim which is twofold: (i) To know if these geographic differences lead to differences in perception of psychosocial risks; and (ii) to identify the job demands and resources with the highest impact on work engagement and performance. A sample of 4,451 people from the sanitary sector, pertaining to 75 Spanish hospitals, was analyzed to test the hypotheses. ANOVA results demonstrated that women show significantly higher impact values in job demands than men, as well as higher values in job resources. Moreover, the group of younger people (< 40 years) showed significantly lower levels in demands, and significantly higher in job resources, wellbeing, and organizational outcomes. Finally, multi-group SEM analyses showed that the impact of job demands and resources on work engagement and performance is significant, regardless of sex and age, although there are changes in the coefficients. The differences in the perception of job demands and resources of the different demographic groups can be used to develop specific psychosocial intervention in health care workers.
Sub‐Auroral Flows and Associated Magnetospheric and Ionospheric Phenomena Developed During 7–8 September 2017
Authors: Horvath Ildiko , Lovell Brian C. 
Published: March 2023

AbstractThis study investigates the Sub‐Auroral Polarization Streams (SAPS) and Sub‐Auroral Ion Drifts (SAID) along with the associated magnetospheric and ionospheric phenomena developed during 7–8 September 2017. Then, a series of substorms occurred before and during the geomagnetic storm (SYM‐Hmin = −146 nT). Results are obtained by utilizing multi‐point observations. These show that during the pre‐storm period, when the ElectroMagnetic Ion‐Cyclotron waves resulted in drop‐out events, a series of sunward (westward) SAID‐in‐SAPS flows developed in the dusk‐midnight sector due to the small‐scale flow bursts reaching the SAPS channel and the westward SAPS flows were streaming antisunward after midnight. During the storm period, dawnside sunward (eastward) SAPS also developed, Kelvin‐Helmholtz (K‐H) vortices rolled along the magnetopause and the hot zone became structured by reflected K‐H waves near the plasmapause leading to auroral undulations (AUs). New findings include the correlation of AUs and K‐H waves in the structured hot zone implying that the Near‐Earth Plasma Sheet acted as a resonator after activation by the K‐H vortices on the magnetopause. Further evidence is provided by the dayside Equatorward Boundary Intensification and Poleward Moving Auroral Forms of which development was supported by the K‐H vortices on the magnetopause by carrying the magnetosheath plasma into the magnetosphere. Adding to previous studies, new results also include the correlated observations of storm‐enhanced density (SED) plume and poleward drifts underlying both the equatorward plasma bubbles and the higher latitude plasma density depletions, and thus verifying their poleward movement within the SED base and SED plume.
Local Earthquake Seismic Tomography Reveals the Link Between Crustal Structure and Volcanism in Tenerife (Canary Islands)
Authors: Koulakov Ivan , D'Auria Luca , Prudencio Janire , Cabrera‐Pérez Iván , Barrancos José , Padilla Germán D. , Abramenkov Sergei , Pérez Nemesio M. , Ibáñez Jesús M. 
Published: March 2023

AbstractVolcanic activity on Tenerife Island is extremely diverse. Three radial rift zones are characterized by cinder cones from basaltic fissure eruptions. A triple junction in central Tenerife exhibits a complex of merged, predominantly phonolitic, stratovolcanoes. The Las Cañadas caldera and widespread ignimbrite deposits reveal high explosive potential. We investigated the crustal and upper mantle structure beneath Tenerife using local earthquake data recorded by two dense seismic networks on the island. For our tomographic inversion, we selected >130,000 P‐ and S‐wave arrivals from ∼6,300 events that occurred during seismic unrests in 2004–2005 and 2017–2021. Synthetic tests confirmed that we could robustly resolve seismic velocity structures to ∼20 km depth. In the upper crust (down to ∼7 km) beneath central Tenerife, a prominent high‐velocity anomaly represents the rigid core of the volcanic complex; at greater depths, a strong low‐velocity anomaly reveals abrupt crustal thickening. Vp and Vs contour lines of 5.2 and 2.85 km/s, respectively, reveal Moho depth variation; crustal thickness beneath Las Cañadas reaches ∼17 km, whereas that beneath other parts of Tenerife is ∼10 km. An anomaly at ∼5 km beneath the caldera with low Vp, low Vs, and high Vp/Vs might be associated with a major phonolitic magma reservoir. Similar anomalies at ∼ sea level may represent shallow magma sources responsible for recent eruptions. Seismicity occurs in a columnar area of high Vp, high Vs, and low Vp/Vs, and may represent hydrothermal fluid migration through brittle media. Based on our results, we constructed a conceptual model of volcanic activity on Tenerife.
Eddy‐Freshwater Interaction Using Regional Ocean Modeling System in the Bay of Bengal
Authors: Paul Nihar , Sukhatme Jai , Gayen Bishakhdatta , Sengupta Debasis 
Published: March 2023

AbstractEddy‐freshwater interaction is studied in the north Bay of Bengal (BoB) with a high‐resolution simulation using the Regional Ocean Modeling System. Following observations, the model simulates the trapping and homogenization of river water by a cyclonic mesoscale eddy on a submonthly time scale from October to November 2015. As fresh river water is trapped in the eddy, it is characterized by strong vertical and lateral gradients in salinity. Within a few weeks, these gradients relax along with the progressive homogenization of freshwater within the eddy. A mixed‐layer salinity budget shows the importance of ageostrophic vertical advection in addition to lateral advection during the evolution of salinity within the eddy. An analysis of the eddy kinetic energy (EKE) budget in the upper ocean indicates the development of barotropic and baroclinic instabilities. The vertical profiles of EKE conversion terms reveal that the surface freshwater was involved in the evolution of baroclinic instability within the mixed layer. In addition, an eddy available potential energy (EPE) budget shows that the entrainment of the river water raises the EPE, which is due to an increase in lateral salinity gradients across the eddy during the trapping event. Subsequently, the salinity homogenization leads to a decrease in the EPE, and its rate of decay is modulated by a correlation between surface buoyancy fluxes and density anomalies. Finally, reanalysis data show similar trapping and homogenization of freshwater events across multiple years, highlighting the importance of this mechanism on the subseasonal time scale in the BoB.