bluuebunny/crossref_metadata_2025 huggingface dataset:
Prenatal Sex Role Stereotypes: Gendered Expectations and Perceptions of (Expectant) Parents
Authors: Imhoff Roland , Hoffmann Lisa
Published: March 2023

People assign attributes to a different degree to other persons depending on whether these are male or female (sex role stereotypes). Such stereotypes continue to exist even in countries with lower gender inequality. The present research tested the idea that parents develop sex role consistent expectations of their babies’ attributes based on fetal sex (by ultrasound diagnostic), as well as gendered perceptions of their recently newborn babies. A total of 304 dyads of predominantly White expecting parents from Germany were followed over the course of pregnancy until after the birth and completed a sex role inventory on their babies’ expected (before birth) as well as perceived traits (after birth). Specifically, they rated to what extent they expected their babies to have normatively feminine traits (e.g., soft-spoken and warm) and normatively masculine traits (e.g., independent and assertive) twice before birth (first half of pregnancy, six weeks before due date) and to what extent they perceived their baby to have these traits eight weeks after birth. The results suggested that fathers held gendered expectations and perceptions, whereas mothers did not. These results suggest that male and female babies are likely to encounter sex role stereotypes about their alleged attributes as soon as their birth.
The origin of free-floating planets
Authors: Miret-Roig Núria
Published: March 2023

Free-floating planets (FFPs) are the lightest products of star formation and they carry important information on the initial conditions of the environment in which they were formed. They were first discovered in the 2000 s but still few of them have been identified and confirmed due to observational challenges. This is a review of the last advances in the detection of these objects and the understanding of their origin. Several studies indicate that the observed fraction of FFPs outnumbers the prediction of turbulent fragmentation and suggest that many were formed in planetary systems that were later abandoned. The JWST will certainly constitute a new step further in the detection and characterisation of FFPs. To interpret these new observations, precise ages for the nearby star-forming regions in which they were formed will be necessary.
Data modeling and NLP-based scoring method to assess the relevance of environmental regulatory announcements
Authors: Thimm Heiko
Published: March 2023

The constantly growing body of global environmental legislation necessitates that corporate environmental compliance managers frequently assess the relevance of new regulations and regulation revisions for each of their sites. Companies are pressured to streamline and automate this crucial task through digital workflows and specialized IT-based assistance systems. This has recently piqued the interest of researchers working in different disciplines, such as intelligent systems, machine learning, and natural language processing. The article describes the latest results of our long-term research program on IT-based support for corporate compliance management, offering insights for these, and other disciplines. The context and the main aspects of environmental regulation announcements and the relevance assessment task are analyzed. An extensive conceptual data model is developed that serves as a foundation for tailoring a generic method to perform a relevance assessment that considers site-specific individual environmental compliance facts. The method uses heuristic data operations and various text processing techniques from the field of natural language understanding. In order to exemplify the method, two application scenarios are described in which the relevance of new waste management directives are assessed for a multi-site production company.
Is Rational Manipulation Permissible?
Authors: Breakey Hugh
Published: March 2023

Rational manipulationis constituted by the following conditions: (i) A aims to persuade B of thesis X; (ii) A holds X to be true and rationally justifiable; (iii) A knows of the existence of evidence, argument or information Y. While Y is not itself misinformation (Y is factually correct), A suspects B might take Y as important evidence for not-X; (iv) A deliberately chooses not to mention Y to B, out of a concern that it could mislead B into believing not-X; and, (v) B has no compelling reason to expect A will avoid mentioning Y in this way. A’s behavior isrationalinsofar as A aims to use reasons to persuade B to believe a thesis that A holds as true and justified. Yet it ismanipulationbecause A deliberately avoids furnishing B with information that B might regard as relevant, to ensure B arrives at the correct belief. I argue that we have good reason to think that A’s action will be wrongly manipulative because it disrespects B’s consent, epistemic autonomy, and personal autonomy. That said, context is critical, and there are many times evidence is intentionally occluded that are not rational manipulation. Even so, ethical arguers should beware of ambiguous contexts, such as when there are conflicting expectations about argumentation roles and goals.
Greenlandic glacial rock flour improves crop yield in organic agricultural production
Authors: Gunnarsen Klara Cecilia , Jensen Lars Stoumann , Rosing Minik T. , Dietzen Christiana
Published: March 2023

The application of mechanically crushed silicate minerals to agricultural soils has been proposed as a method for both improving crop yields and sequestering inorganic carbon through enhanced mineral weathering. In Greenland, large quantities of finely grained glacial rock flour (GRF) are naturally produced by glacial erosion of bedrock and deposited in easily accessible lacustrine and marine deposits, without the need for energy-intensive grinding. To determine if this material can improve crop yields, we applied 10 and 50 t GRF ha−1 to a sandy, organic agricultural field in Denmark. Two field trials were carried out to test the first-year yield response to GRF in both maize and potatoes, residual effects on potato yields in the year after application, and second and third-year residual effects on spring wheat. Reference-K treatments were included for comparison to determine if the beneficial effects of GRF were primarily due to its K content (3.5% K2O). This alternative source of silicate minerals improved crop yields in the year of application. Though there was no improvement in yield with the reference-K treatments, for each additional ton of GRF applied, maize dry yield increased by 59 kg ha−1 and potato tuber yield by an additional 90 kg ha−1. No residual effects on crop yields were observed in the following years, but we suspect that benefits might persist over multiple seasons at sites with lower initial fertility. The increase in yields achieved with GRF could offset some of the costs of applying silicate minerals as a CO2 sequestration scheme.
SGPAC: generalized scalable spatial GroupBy aggregations over complex polygons
Authors: Abdelhafeez Laila , Magdy Amr , Tsotras Vassilis J.
Published: March 2023

This paper studies the spatial group-by query over complex polygons. Given a set of spatial points and a set of polygons, the spatial group-by query returns the number of points that lie within the boundaries of each polygon. Groups are selected from a set of non-overlapping complex polygons, typically in the order of thousands, while the input is a large-scale dataset that contains hundreds of millions or even billions of spatial points. This problem is challenging because real polygons (like counties, cities, postal codes, voting regions, etc.) are described by very complex boundaries. We propose a highly-parallelized query processing framework to efficiently compute the spatial group-by query on highly skewed spatial data. We also propose an effective query optimizer that adaptively assigns the appropriate processing scheme based on the query polygons. Our experimental evaluation with real data and queries has shown significant superiority over all existing techniques.
Industrial Design education in Australia: a competence analysis across primary, secondary and tertiary education levels
Authors: Deighton Kathryn , Kuys Blair , Tyagi Shivani
Published: March 2023

Industrial Design education is poorly understood by laypeople but is present in Australian curricula from primary through to tertiary education levels. Designers and design researchers have long recognised the value of the broad-ranging skills, knowledge fields, and personal qualities design education imparts, but this understanding is generally not shared by the wider community who may see design as surface decoration. This research identifies indicators of value and relevance taken from the twenty-first century competences literature, then measures their presence in four different Industrial Design education settings. Two studies were undertaken. First, Industrial Design educators from primary, secondary, and tertiary levels were surveyed. Then diverse Industrial Design education stakeholders from education and non-education settings were interviewed. The studies gathered both quantitative and qualitative data on the value and relevance of current Industrial Design education in Australia. The result is a comprehensive analysis of the twenty-first century competences present in Australian Industrial Design education, which concludes with recommendations for ways Industrial Design education can benefit twenty-first century learners, as well as ways it should evolve to remain relevant.
Implementation of non-linear mixed effects models defined by fractional differential equations
Authors: Kaikousidis Christos , Dokoumetzidis Aristides
Published: March 2023

Fractional differential equations (FDEs), i.e. differential equations with derivatives of non-integer order, can describe certain experimental datasets more accurately than classic models and have found application in pharmacokinetics (PKs), but wider applicability has been hindered by the lack of appropriate software. In the present work an extension of NONMEM software is introduced, as a FORTRAN subroutine, that allows the definition of nonlinear mixed effects (NLME) models with FDEs. The new subroutine can handle arbitrary user defined linear and nonlinear models with multiple equations, and multiple doses and can be integrated in NONMEM workflows seamlessly, working well with third party packages. The performance of the subroutine in parameter estimation exercises, with simple linear and nonlinear (Michaelis–Menten) fractional PK models has been evaluated by simulations and an application to a real clinical dataset of diazepam is presented. In the simulation study, model parameters were estimated for each of 100 simulated datasets for the two models. The relative mean bias (RMB) and relative root mean square error (RRMSE) were calculated in order to assess the bias and precision of the methodology. In all cases both RMB and RRMSE were below 20% showing high accuracy and precision for the estimates. For the diazepam application the fractional model that best described the drug kinetics was a one-compartment linear model which had similar performance, according to diagnostic plots and Visual Predictive Check, to a three-compartment classic model, but including four less parameters than the latter. To the best of our knowledge, it is the first attempt to use FDE systems in an NLME framework, so the approach could be of interest to other disciplines apart from PKs.
Techno-economic evaluation of buffered accelerated weathering of limestone as a CO2 capture and storage option
Authors: De Marco Serena , Varliero Selene , Caserini Stefano , Cappello Giovanni , Raos Guido , Campo Francesco , Grosso Mario
Published: March 2023

Carbon dioxide storage technologies are needed not only to store the carbon captured in the emissions of hard-to-abate sectors but also for some carbon dioxide removal technologies requiring a final and permanent storage of CO2. The pace and scale of geological CO2 storage deployment have fallen short of expectations, and there is a growing interest in ocean-based CO2 storage options. As complementary to geological storage, buffered accelerated weathering of limestone (BAWL) has been proposed to produce a buffered ionic solution at seawater pH, derived from the reaction in seawater between a CO2 stream and a micron-sized powder of calcium carbonate (CaCO3), within a long tubular reactor. The addition of calcium hydroxide to buffer the unreacted CO2 before the discharge in seawater is also envisaged. BAWL avoids the risks of CO2 degassing back into the atmosphere and does not induce seawater acidification. This work presents a mass and energy balance and preliminary cost analysis of the technology for different configurations of discharge depth (100, 500, 3,000 m), pipeline length (10, 25, 100 km) and diameter of CaCO3 particles (1, 2, 10 µm) fed in the tubular reactor. The total energy consumption to capture and store 1 t of CO2 generated by a steam-methane reforming (SMR) process ranges from 1.3 to 2.2 MWh. The CO2 released from the CaCO3 calcination to produce the buffering solution leads to a total CO2 storage requirement 43–85% higher than the CO2 derived by SMR. The total cost to capture and store 1 t of CO2 from SMR is estimated in the range 142–189 €.
A differentiated approach to Indigenous pedagogies: addressing gaps in teachers’ knowledge
Authors: Funk Johanna , Woodroffe Tracy
Published: March 2023

Acknowledging Australian Indigenous cultural diversity involves respecting local Indigenous knowledge and perspectives. This can be difficult for teachers who do not know about Indigenous people and their knowledge. The Differentiated Indigenous Pedagogies project evaluated digitally available information describing Indigenous in this paper, ‘Indigenous’ will be used when referring to First Nations and Aboriginal and Torres Strait Islander peoples, pedagogies, policies, and institutional contexts in Australia apart from references used which use other terminology. The authors acknowledge the contested nature of terminology and use the term ‘Indigenous’ as it is consistent with the title of the research project on which this article is based pedagogies in the Northern Territory. The purpose was to consolidate findings to increase positive intercultural actions in the wider education community. An important aspect of the project is addressing gaps in western, non-Indigenous teacher knowledge pertinent to the diversity within Indigenous language groups and regions. Through searching for available Indigenous pedagogies as a teacher might, we found information differs in description and levels of relationality. Pedagogies are presented in numerous ways which complicates teachers’ cultural understandings. Common themes from search results and Indigenist educational research are used to define ways teachers can actively engage in more respectful, relational, and reconciliatory ways to develop a differentiated approach for themselves to use when working with Indigenous pedagogies.
When Men Fell from the Sky
Authors: Andrieu Claire
Published: March 2023

Between 1940 and 1945, more than 100,000 airmen were shot down over Europe, a few thousand of whom survived and avoided being arrested. When Men Fell from the Sky is a comparative history of the treatment of these airmen by civilians in France, Germany and Britain. By studying the situation on the ground, Claire Andrieu shows how these encounters reshaped societies at a local level. She reveals how the fall of France in 1940 may have concealed an insurrection nipped in the bud, that the 'People's War' in Britain was not merely a myth, and that in Germany, the 'racial community of the people' had in fact become a social reality with Allied airmen increasingly subjected to lynching from 1943 onwards. By considering why the treatment of these airmen contrasted so strongly in these countries, Andrieu sheds new light on how civilians reacted when confronted with the war 'at home'.
The size of a Markovian SIR epidemic given only removal data
Authors: Ball Frank , Neal Peter
Published: March 2023

During an epidemic outbreak, typically only partial information about the outbreak is known. A common scenario is that the infection times of individuals are unknown, but individuals, on displaying symptoms, are identified as infectious and removed from the population. We study the distribution of the number of infectives given only the times of removals in a Markovian susceptible–infectious–removed (SIR) epidemic. Primary interest is in the initial stages of the epidemic process, where a branching (birth–death) process approximation is applicable. We show that the number of individuals alive in a time-inhomogeneous birth–death process at time
$t \geq 0$
, given only death times up to and including time t, is a mixture of negative binomial distributions, with the number of mixing components depending on the total number of deaths, and the mixing weights depending upon the inter-arrival times of the deaths. We further consider the extension to the case where some deaths are unobserved. We also discuss the application of the results to control measures and statistical inference.
The Many Faces of Nationalism
Authors: Malešević Siniša
Published: March 2023

This article reviews three recent books on nationalism, each focusing on a different aspect of this multifaceted phenomenon. Mylonas and Radnitz’s volume explores the relationships between nationalism and the politics of treason, Hadžidedic’s book zooms in on the historical interdependence of capitalism and nationalism, while Maxwell’s historical monograph explores nationalist habitus as a form of lived experience. These three insightful contributions show the diversity and plasticity of nationalist ideology and practice.
An experimental investigation of the aerodynamic characteristics of a cascade of circulation controlled aerofoils
Authors: Flint W. L. , Holliday C. I.
Published: March 2023

Typical performance characteristics are presented for a cascade of two-dimensional bluff aerofoils employing circulation control from a tangential blowing jet. The cascade was tested in various configurations at a freestream Mach number of 0·3 and Reynolds number of approximately 1·5 x 105. Lift and drag coefficients and stream deflection are related to the blowing jet momentum coefficient. The expressions employed for lift and drag eliminate the direct effect of the blowing jet on measured performance, which was found to be influenced strongly by vortex shedding at low jet blowing rates.

For the configurations employed, tests showed that the economical application of circulation control on an uncambered blade could produce flow turning angles up to 20°.
System characteristics of direct broadcasting
Authors: Blonstein Larry
Published: March 2023

This paper is intended to set the scene for the presentations that will follow. It looks at the characteristics of the direct broadcast TV services that were agreed internationally at the 1977 World Administrative Radio Conference (WARC) and at the effects of these characteristics on the communications link and thus on the spacecraft that will provide the services.
L-SAT direct broadcast applications
Authors: Clouston D.
Published: March 2023

The first major step in the L-SAT programme was the publication by ESA in 1979 of the report ESA/EXEC (79) 3, (known as the ‘Blue Book’) which identified the market potential for a ‘large’ communication spacecraft and many of the essential features required to service the market needs. One of these features was the desirability for a multi-purpose platform which is now the basis of the overall L-SAT programme and the prime objective of the L-SAT 1 mission.
A commercial view of DBS
Authors: Flach Dennis
Published: March 2023

Most of the new services and facilities which, we are told, are going to provide us with new images on the TV screen in the next decade, are led by technology rather than by any established need by the viewer or consumer.

In looking at the commercial viability of DBS services it is necessary to consider how the viewer is likely to react, not only with regard to acquiring receiver equipment but also the extent to which he is going to use it.
Vibration of waffle cylinders
Authors: Karmakar R.
Published: March 2023

A vibration analysis of waffle cylinders with various stiffener configurations is made using the energy method. The frequency factors of the stiffened cylinders are obtained in terms of various non-dimensional parameters. To make a comparative study, the frequency factors are maximised for a fixed cylinder mass and stiffener eccentricity ratio. It is observed that spiral and circumferential configurations are efficient whereas axial stiffening is detrimental.
Preliminary report on the engineering development of the Magnus Aerospace Corp. LTA 20-1 heavy-lift aircraft
Authors: Delaurier J. D. , McKinney W. D. , Kung W. L. , Green G. M. , Scholaert H. S. B.
Published: March 2023

Within the past few years, there has been a growing interest in the utilisation of airships for a variety of missions. Studies funded by NASA and the US Navy have shown that modern airships not only could perform certain tasks more economically and silently than other aeronautical vehicles (short-haul passenger and freight transport, and long-duration ocean patrol), but that they could perform unique missions, such as the V/STOL transportation of bulky loads an order of magnitude beyond helicopter capability.

The types of modern airships envisioned fall into two categories: modernised blimps and heavy-load carriers. Blimps are receiving reconsideration for their traditional role of patrol and surveillance because of their fuel efficiency and the development of modern sensing devices which require a quiet, stationary vehicle for deployment.
Testability—a military users point of view
Authors: Lawrence G. F. , Webber S. T. , Witcombe P. J.
Published: March 2023

The topic of testability in equipment appears to generate as many different views as people asked to express an opinion. Certainly, a manufacturer's perceptive of testability appears to vary from the equipment user view. Both will agree that testability is an essential characteristic of equipment but its need is driven by different requirements. This paper presents a view of testability as seen by the users of complex military equipment in the three services. The general thesis is that the testability needs of the Royal Navy, Army and Royal Air Force must receive greater attention than at present given and that each element of the Armed Forces is faced with maintaining equipment for 20 years or more whereas industry has a much shorter period of interest.

In developing this thesis the paper starts by discussing the military requirements for testability and outlining the maintenance philosophies adopted by the three services. Procedures for establishing an effective testability programme, as part of the overall design effort, are then considered and a possible technique for the numerical assessment of testability is mentioned. Finally the paper emphasises the importance the three Services attach to the transportability of test software.
Reliability testing for GW systems
Authors: O'Connor Patrick D. T.
Published: March 2023

Reliability testing for GW systems can be considered as comprising five categories of test:

1.

Development testing, including environmental testing, to ensure that the design is capable of performing to the technical requirements.

2.

Reliability demonstration testing, to provide assurance that the reliability requirements will be, or are being, met.

3.

Production Testing.

4.

Acceptance testing, to provide assurance that production missiles are achieving the required reliability.

5.

In-service testing, to ensure that reliability is maintained during Service conditions.

This paper surveys the particular problems experienced when applying these categories of reliability testing to guided weapons. The paper considers only the equipment in the missile, and not GW sub-systems fitted to launch vehicles, since such sub-systems are basically the same as other avionic, ground or ship-based systems from the reliability test point of view.
The European transonic wind-tunnel ETW: A cryogenic solution
Authors: Hartzuiker J. P.
Published: March 2023

The history of the European Transonic Wind-tunnel is briefly described.

After a discussion of the tunnel specifications and performance, a general description of the facility is provided.

The results of an investigation into the expected future use of the tunnel are summarised.

Information on the pilot tunnel PETW is presented, as well as some results on flow quality obtained in an aerodynamic test rig.

Finally, some reference is made to a supporting programme on cryogenic technology.
Part II: For the nacelle in oscillatory motion
Authors: Sheu M. J. , Hancock G. J.
Published: March 2023

The vortex lattice model developed in Part I has been extended to estimate the overall loads and moments on a cylindrical nacelle alone and on a cylindrical nacelle, enclosing an engine, when the configuration oscillates in simple harmonic motion in an air stream. Results are presented for a range of frequency parameter and thrust conditions. Although the problem is properly posed for low speed flow through the ‘engine’, there is doubt over the model formulation when density changes need to be accounted for.
Technology for profitable transportation
Authors: Burgess Pat
Published: March 2023

With the close relationship which exists between the airline industry and aerospace, it is appropriate to begin an aerospace technology symposium with a short review of what the airline industry has achieved and where it is now going. The timing is similarly appropriate because it is the 50th anniversary of the true beginnings of the airline industry. Boeing introduced its B247 into service at the end of 1933, and Douglas followed with its DC2 in 1934. Both aircraft were major steps from previous technology, and created the equipment base from which air transportation could develop. At the same time, the Air Mail Act of 1934 created the organisational environment in which the industry could flourish and, inter alia, compelled Boeing and United Aircraft to divest themselves of airline interests and marked the true beginning of United Air Lines. TWA and American had preceded it by a few months, while General Motors were persuaded to sell off Eastern Air Linesonly a few weeks later.
The first spacelab payload (FSLP)
Authors: Shapland D. J.
Published: March 2023

The objectives of the first flight of Spacelab (to be launched in September 1983) are to verify the Spacelab performance and to demonstrate its use as a tool for experimentation in a variety of scientific and technical disciplines. The latter objective will be achieved by the operation of a joint ESA-NASA payload wherein about 50% of the available resources are allocated to the complements of each Agency. The total payload amounts to 2785 kg and consumes about 2 kW of power. The configuration chosen for the first mission (orbital inclination 57°, altitude 250 km, duration nine days) is a long module plus one pallet and some 70 experiments will be on-board.

The paper describes the total payload but particular attention is given to the European portion — FSLP (First Spacelab Payload). The scientific objectives of the mission are presented and representative experiments from the various disciplines (Atmospheric Physics, Earth Observations, Material Sciences, Plasma Physics, Astronomy and Solar Physics, Life Sciences and Technology) are described. The tasks associated with check-out and integration of the individual experiments and their related software into the FSLP are explained and the associated ground operations and flight operations planning portrayed. In the latter context, the Tracking and Data Relay Satellite System (TDRSS) and the Payload Operations Control Center (POCC) play an important part. The role of the on-board crew is stressed and the general advantages of man-in-the-loop are discussed.

Finally, some of the complex management inter faces are illustrated and the paper explains how this challenge has been met. It is concluded that the considerable experience gained from this international joint venture into manned space flight must be retained for the optimum fulfilment of future European man-tended space experimentation.
The cost definition phase of a new commercial aircraft programme
Authors: Loeken W.G.
Published: March 2023

A commercial aircraft programme has always been an undertaking with significant risk. Accurately estimating potential sales and production costs of these aircraft is an essential part of containing this risk. This paper addresses the cost estimating process and cost management of the latest Boeing programme — the 757.

Substantial resources are required for a new programme. The number of people involved, of course, varies with the stage of production, but Boeing will employ approximately 10,000 at peak production rates. In a typical Boeing programme, a network of over 1000 suppliers of material, parts and equipment will employ another 20 000 people at peak production so that total employment is in the 30 000 range.
Hydrodynamics and aerodynamics — cross fertilisation in research and design
Authors: Pearcey H.H.
Published: March 2023

Hydrodynamics and aerodynamics start as one science and retain an extensive common base, including, for example, a wealth of fundamental theory and observation of streamline flows, boundary layers and vortical motions, (Plate 1).

But research and design have opened up the two frontiers in different directions, to support and often to lead the evolution and development of the respective fields of application — ships and aeroplanes, or ships and helicopters, or helicopters and other marine structures.

We are reminded of how far the helicopter has become an integral and indispensible part of the maritime scene and of so many maritime operations, and this is one of the best tributes to the great pioneering genius, drive and enthusiasm of Raoul Hafner who is very much in our minds as we consider the possibilities and prospects for cross fertilisation.
The role of information feedback in aircrew training and its impact on the debriefing facilities
Authors: Waag W. L.
Published: March 2023

In the few moments that I have, I would like to discuss in very general terms the role of information feedback in aircrew training and make the case that there is a need for improved computer-based debriefing aids. I am sure that there is little disagreement today that flight simulators offer a range of benefits. Such things as cost savings, reduced energy expenditure, safety and availability have been mentioned again and again. However, the most important benefit to be derived, namely training, is often-times overlooked. The assumption is often made that a good simulator, in terms of its fidelity, will lead to good training. While there are certainly examples of this, there are also cases of good simulators providing poor training because of improper utilisation, and cases of poor simulators providing very good training. The key appears to be in the proper utilisation of the simulator as a trainer, which in turn, is partially based on the simulators instructional features.
Low cost aircrew training devices
Authors: Knight M. A. G.
Published: March 2023

The purpose of this talk is to describe some of the more simple aids used in the training of aircrew and to illustrate how they can be integrated with flight simulators and aircraft to form a systematic approach to aircrew training. Of course, low cost aids do not solve all training problems, neither can they replace the aircraft or the flight simulator for many tasks, but they are worth examining for reasons which will appear in this paper.

As a start, it might be useful to look at a typical flight simulator and note some of its characteristics as a teaching device.
The micro revolution comes to civil air transport
Authors: Ryland Mark
Published: March 2023

The microprocessor revolution can in no way be described as a ‘silent’ revolution, unusually perhaps, a technological advance has caught the imagination of the mass media, who are fond of postulating its effect on our lives.

Within the Air Transport industry much coverage has been given to the development of ‘visibly’ different avionic equipment such as cathode ray tube (CRT) flight instrumentation, active control technology and flight management systems. These advances have been made possible solely on account of the microprocessor, which has, in addition, also revolutionised existing avionic disciplines.
Peaked velocity profile generation
Authors: Laws E. M.
Published: March 2023

Morgan and Saunders have shown that highly peaked velocity profiles can be produced in a pipe downstream of a partial gauze screen, a screen pierced by a central hole. By systematically varying the ratio of hole size, d, to pipe diameter, D they obtained peaked profiles with different values of profile peakiness û/ū.

The investigation showed that two different velocity profiles with the same value of û/ū. could be produced from a particular gauze, one from a screen with d/D <0·5 and the other with d/D>0·5.
A user’s view
Authors: Lucking A. J.
Published: March 2023

Though billed as an honorary consultant to the Air Transport Users Committee, I must underline that I speak for no one but myself, as irritated BEA advocates used to point out to the Air Transport Licensing Board in the old days.

The airline user is concerned with the real price of his ticket, or freight invoice, though he realises that this is related to the cost of producing the service. His complaints are first, that the fare structure is often unfair, and furthermore fails to maximise the revenue earning opportunity: and secondly, many airlines’ staff costs are far too high.
Practical application of the rapid frequency sweep technique for structural frequency response measurement
Authors: White R. G. , Pinnington R. J.
Published: March 2023

The rapid frequency sweep technique is the result of a considerable amount of research into the development of a transient method for the rapid measurement of structural frequency response, digital data analysis procedures being used to derive the required dynamic characteristics. Theoretical analyses, together with the results of experimental studies and experience gained during structural testing are presented here which illustrate practical considerations and limitations of the method; these range from discussion of exciter attachment, effects of transducers and choice of instrumentation to signal processing methods and related criteria. A simple guide to practical structural testing is given in the final section which outlines procedures to be followed during testing and signal acquisition.
The aircraft manufacturer’s approach to airworthiness
Authors: Troughton J. , Grigg R.
Published: March 2023

Airworthiness — fitness for flight — is one of the main factors influencing aircraft design. This joint paper discusses the problems of managing airworthiness and some of the methods used in an aircraft design organisation dealing with new and development designs and ‘in service’ aircraft.

External standards of airworthiness are set by many national and international authorities and it is vital that the aircraft manufacturer plays his part in setting these standards so that the implication on operational economics and production liability are considered. In addition the manufacturer sets his own internal standards of airworthiness. The relationship between civil and military airworthiness requirements are reviewed.
The urban heliport
Authors: Ward D. J.
Published: March 2023

There seems to be a preconceived notion amongst an element of urban society that a heliport in its midst can contribute nothing worthwhile to it. The uneducated conjure fears of noise, added road congestion and hazard to both person and property. The prejudiced choose to think in terms of pandering to the privileged. In reality the effect of a heliport upon its urban environment, once the dust of cautious suspicion has settled, is likely to be unnoticeable by all but a very few persons. Noise levels need not be onerous, demands on roads and real estate are likely to be minimal whilst safety may remain fundamentally inviolate.
The IFR heliport
Authors: Free F. W.
Published: March 2023

A heliport criteria exclusively for major metropolitan heliports was developed by the International Air Transport Association (IATA) as far back as 1955 and was developed to provide guidance to the helicopter operator and to those concerned with the planning, construction and regulation and operation of heliports. It is interesting to note that although at that time there had been no operating experience with either turbine powered helicopters or multi-engined helicopters this criteria has remained in broad outlines very similar over the years. It is however, sad to relate that some 27 years after this IATA criteria was drafted we still do not have a full IFR Metropolitan heliport as then envisaged. I hope to examine some of the reasons for this and to review the current prospects and requirements for a full IFR heliport.
A supersonic V/STOL fighter design project
Authors: Fielding J. P.
Published: March 2023

The College of Aeronautics performs an annual group design project as a major part of its Aircraft Design MSc programme. Projects are chosen to be representative of current areas of interest and the programme is carried out in a manner which is as close as possible.to that of aircraft manufacturers.

Vice Admiral Forrest S. Peterson, Commander Naval Air Systems Command, said at the AIAA/NASA-Ames V/STOL Conference in 1977 that:

V/STOL appeared to be the most effective, most economical means of addressing many of our major military needs: dispersal of air assets over a broad geographic range, reducing the present reliance on relatively few ships and large permanent bases and reducing the cost of maintaining an adequate, efficient air arm.
Cost control of aircraft manufacture a modern approach
Authors: Jackson E. T.
Published: March 2023

Bonus schemes have tended to fall into disrepute and have been neglected; this is a pity because they are an extremely powerful tool when applied successfully. One of the weakest areas of the individual bonus scheme for cost control was the setting of standards through individual negotiation influenced by many factors, rather than by estimating the work content.

During 1975, the individual bonus scheme was suspended at British Aerospace Weybridge-Bristol Division, Filton Site, and a start was made on the development of a cost control system based on work measurement and using modern computing techniques. The new system had to contain two essential features. First, the speedy identification of jobs giving problems on the shop floor, since it was realised that the suspension of the individual bonus scheme would slow down this process, secondly the provision of a fast and reliable method of checking the work issued to the shops against the original estimates.
Initial design of stringer stiffened bend boxes using geometric programming
Authors: Snell M. B. , Bartholomew P.
Published: March 2023

The technique of geometric programming is applied to the design of optimum wing bend boxes in sheet-stringer-rib construction. The work extends the previous application in multi-spar design and the results for the different configurations are compared. Closed-form design equations are given for the case of buckling constraints whereas more complex formulations with stress constraint were solved by computer.
Noise research
Authors: Cheeseman I. C.
Published: March 2023

The development of the jet engine produced jet noise problems. Most of the understanding of jet noise was and is performed in universities. The fundamental and quite exceptional work of Lighthill was followed by that of Curie. Powell and Ffowcs Williams at Southampton in the early 1950s and was paralleled by experimental investigations on noise suppression by for example. Lilley at Cranfield. This university work was used to form the basis of a programme of research into jet engine noise at Ministry of Aviation establishments with considerable university inputs which established a commanding lead for the United Kingdom in the understanding of jet noise.

The formation of the Institute of Sound and Vibration Research at the University of Southampton under the inspiration of Professor E. J. Richards was a step which placed university research at a different level to that usually observed in the United Kingdom by concentrating in one place some 40-50 people all devoted to research and postgraduate education.
Structures and materials
Authors: Davies G. A. O.
Published: March 2023

Universities should be able to do two things which industry may not be able to do, and which should be valuable. We are supposed to be able to have time to think instead of continuously meeting deadlines (this is hardly true anymore) and so we can:

1.

Take a risk and embark on a novel idea which may not come off. If the gamble works then we publish and promote it for the general good.

2.

Recognise that industry has to meet deadlines, and often produce an answer to a problem which is only partially understood. We can then look at the problem in depth, and with better understanding point the way to future development.
Contribution to RAeS discussion evening
Authors: Young A. D.
Published: March 2023

I hope that it will be clear from the brief accounts you have just heard that not only have the universities in the UK made a major contribution to the status and health of the aerospace industry but, given a modicum of encouragement, they can continue to do so. Indeed, I maintain for reasons that I shall make clear that the part that they can and should play is of greater importance now than ever.
Development of European Avionics Standards — 20th Anniversary of EUROCAE
Authors: McWiggan T. J.
Published: March 2023

The role of the International Civil Aviation Organisation (ICAO) in developing standards and recommended practices for communication, navigation and surveillance systems is well known. The emphasis is on system characteristics and the definition of airborne equipment is limited to essential characteristics. For many years, the world’s airlines have collaborated in the Airline Electronic Engineering Committee of ARINC to produce engineering characteristics to ensure interchangeability and hence freedom of choice in their selection of airborne equipments. Thus ‘box’ dimensions, types and pin connection, interfaces cabling, coding etc are covered.

For the electronics industry designing equipment to meet the needs of both the aircraft constructors and their customers, the airlines and the Airworthiness Authorities responsible for the certification of equipment installed in passenger carrying aircraft more detailed specifications are essential. This problem was recognised in the USA and a solution was found in the formation of the Radio Technical Commission for Aeronautics (RTCA). With the direct support and involvement of USA Government Departments, the Electronics and Aircraft Construction Industry, the Airlines and General Aviation operating as ‘Special Committees’ of experts, RTCA developed Minimum Performance Standards. These documents are used by the FAA as the basis for equipment certification.
Saving fuel with the wide-chord fan
Authors: Cundy John
Published: March 2023

More than ten years of development have gone into the Rolls-Royce wide-chord fan, which will provide a 2½ per cent fuel saving when it enters service in 1984. This new and highly efficient fan is one of the advanced features of the 535E4 engine, which will have a fuel consumption 10 per cent better than that of the initial Rolls-Royce engine for the Boeing 757, the 535C.

How has this advanced fan been developed and what are its advantages? This article surveys the reasons for its development and the factors involved in this technical advance pioneered by Rolls-Royce.
Digital simulation of counterspun nutation damper operation under non-ideal operating conditions
Authors: Clements R. R. , Wright J. H. , Tonkin S.W.
Published: March 2023

Previous analysis of the operation of the counterspun nutation damper has been restricted to small nutation angles and to axisymmetric spacecraft. This paper develops equations for the dynamics of nutation damper/spacecraft combinations in which the spacecraft is non-axisymmetric and may adopt large nutation angles. In addition, a mechanism to model the growth of nutation due to energy dissipative mechanisms on board the spacecraft is introduced.

The dynamic equations were programmed in a digital simulation language. The effects of three probable imperfections in the construction and operation of nutation dampers on the operating characteristics of the dampers were investigated by simulation. The implications of these non-ideal conditions for the design of counterspun nutation dampers are identified.
Assessment of certain merits of FSW and effect of the sign of the sweep angle on the stressing of a wing structure
Authors: Souahi A.
Published: March 2023

Forward Swept Wings have a number of advantages over Aft Swept Wings which have been appreciated for a number of years. In the past, however, their use has been restricted to limited degrees of sweep because of the severe weight penalty necessary to prevent aerolastic divergence. Recently, it has been shown that the outstanding directional properties of fibrous composites could help overcome this problem by adequate selection of ply orientations and laminate thickness distribution of the wing skin.
A note on the representation of bimodal distributions
Authors: Campion M. C.
Published: March 2023

Reference 1 provides the stimulus for this note, containing, as it does, a trap into which many engineers and statisticians fall. Referring to Fig. 6 of that paper (this was incorrectly labelled — it should have been Fig. 4), a set of observed data is presented on normal probability paper, together with a straight line representing the fitted normal distribution. Since none of the points is far from the line, the conclusion is drawn that the data are well-fitted by a normal distribution.

However, a closer look at the figure shows that the scatter of the ‘observed’ points about the fitted line is not random, but systematic; the first four points all lie above the line, the next six below the line, the next eight above the line, and the last two below the line.
A vectored-thrust rotor for helicopter anti-torque applications
Authors: Molyneux W. G.
Published: March 2023

A rotor concept is described that enables the generation of a controlled thrust vector in any direction within the rotor’s sphere of action. It is suggested that a rotor of this kind might replace the entire tail unit of the ‘conventional’ single-rotor helicopter to provide a lighter, more compact layout of improved performance. An active control system might be required for the ‘flying-tail’ layout envisaged.

Some of the structural and mechanical design problems that are posed by a vectored-thrust (VT) rotor are briefly discussed and are seemingly tractable by exploiting the potential of advanced composite materials.

No assessment is made of the aerodynamic performance of a VT rotor, nor of the helicopter configurations or operational scenarios where a VT rotor might prove advantageous. Some limited assessments of this kind seem merited.
Observations on the highly coned propeller
Authors: Molyneux W. G.
Published: March 2023

The unique aerodynamic features of the highly coned propeller, with cyclic and collective control of blade pitch, are discussed in simplistic terms.

The configuration poses severe structural design problems and, while fibre reinforced composites fabrication might enable these to be surmounted, there will be weight penalties in overcoming them that will limit potential applications.

No outstanding prospect for the propeller is identified, but specialised applications may merit a closer scrutiny of the concept.