bluuebunny/crossref_metadata_2025 huggingface dataset:
N‐Doped sp2/sp3 Carbon Derived from Carbon Dots to Boost the Performance of Ruthenium for Efficient Hydrogen Evolution Reaction
Authors: Liu Zonglin , Li Baoqiang , Feng Yujie , Jia Dechang , Li Caicai , Zhou Yu
Published: July 2022

The structure and properties of the carrier significantly affect the catalytic activity of the active centers for supported electrocatalysts. Therefore, elaborate design and regulation of the physicochemical properties of carbon carriers are essential to improve the activity and stability of the carbon‐supported ruthenium‐based catalysts. Herein, enlightened by the unique characteristics of coexisting sp2 and sp3 carbon nuclei in N‐doped carbon dots (NCDs), a hybrid structure of N‐doped carbon substrates featuring N‐doped sp2/sp3 carbon interfaces loaded with Ru nanoparticles (Ru/NCDs) is obtained. Spectroscopic analysis and density functional theory calculations illustrate that the interaction between Ru and NCDs effectively modulates the electronic structure of the active center Ru, and the formed N‐doped sp2/sp3 carbon interface lowers the energy barrier of the intermediates in hydrogen evolution reaction (HER) and balances the hydrogen adsorption and desorption and, thereby, greatly improves the activity of Ru/NCDs. Remarkably, Ru/NCDs exhibit excellent HER activity and stability in comparison to Pt/C, which merely requires overpotentials as low as 37 and 14 mV at 10 mA cm−2 in alkaline and acidic electrolytes, respectively. This finding will provide more thoughts about the influence of substrate properties on the catalytic activity and rational design of carbon‐loaded electrocatalysts.
Polyethyleneimine Grafted H2O2‐Oxidized Starch Nanocrystals as a Biomaterial for Adsorptive Removal of Cr(VI)
Authors: Chen QiJie , You Na , Zhao YaLan , Liang ChunYan , Liu Zhuo , Zhao WenGuang
Published: July 2022

In this study, a novel biomaterial polyethyleneimine grafted H2O2‐oxidized starch nanocrystals (OSNCs‐PEI) is successfully prepared to remove hexavalent chromium (Cr(VI)) in the solution. The fourier transform infrared spectroscopy and energy dispersive X‐ray spectroscopy confirm that the hydroxyl groups on starch nanocrystals (SNCs) are oxidized to aldehyde groups, and PEI is successfully grafted on the OSNCs. When the pH is 3, the zeta potential of OSNCs‐0.1wt%PEI, OSNCs‐1.0wt%PEI, and OSNCs‐3.0wt%PEI reach the maximum value of +30.4, +43.2, and +46.3 mV, respectively. The effects of contact time, pH, initial concentration, and temperature on the adsorption behavior are investigated. The process of removing Cr(VI) from aqueous solution by OSNCs‐PEI is more suitable when pH is 3 and the adsorption time is 60 min. When the initial concentration of Cr(VI) is 1000 mg L–1, the adsorption capacity of Cr(VI) by OSNCs‐0.1wt%PEI, OSNCs‐1.0wt%PEI, and OSNCs‐3.0wt%PEI are up to 103.56, 173.91, and 184.35 mg g–1, respectively. The adsorption of Cr(VI) by OSNCs‐PEI follows the pseudo‐second‐order kinetic model and the adsorption experimental data fits well the Freundlich adsorption isotherm model. The adsorption of Cr(VI) by OSNCs‐PEI is a spontaneous and endothermic process.
Sentiment Analysis Using State of the Art Machine Learning Techniques
Authors: Balci Salih , Demirci Gozde Merve , Demirhan Hilmi , Sarp Salih
Published: July 2022

Sentiment analysis is one of the essential and challenging tasks in the Artificial Intelligence field due to the complexity of the languages. Models that use rule-based and machine learning-based techniques have become popular. However, existing models have been under-performing in classifying irony, sarcasm, and subjectivity in the text. In this paper, we aim to deploy and evaluate the performances of the State-of-the-Art machine learning sentiment analysis techniques on a public IMDB dataset. The dataset includes many samples of irony and sarcasm. Long-short term memory (LSTM), bag of tricks (BoT), convolutional neural networks (CNN), and transformer-based models are developed and evaluated. In addition, we have examined the effect of hyper-parameters on the accuracy of the models.
Multi-annual comparisons of summer and under-ice phytoplankton communities of a mountain lake
Authors: Obertegger Ulrike , Flaim Giovanna , Corradini Stefano , Cerasino Leonardo , Zohary Tamar
Published: July 2022

Little is known on the dynamics of under-ice phytoplankton communities. We investigated phytoplankton communities in the upper (0–20 m) and lower (30–35 m) layer of oligotrophic Lake Tovel, Brenta Dolomites (Italy) over 6 years during summer and under ice. Winter conditions were different from  one year to another with respect to ice thickness and snow cover. Proxies for light transmission (Secchi disc transparency, light attenuation) were similar between seasons, even though the incident solar radiation was lower in winter. Algal richness and chlorophyll-a were not different between seasons while biomass was higher during summer. In four of the 6 years, Bacillariophyta dominated during summer and Miozoa (class Dinophyceae) under ice while in 2 years Bacillariophyta also dominated under ice. Generally, a shift to larger size classes from summer to under ice was observed for Bacillariophyta, Chlorophyta, and Ochrophyta (class Chrysophyceae) while Dinophyceae showed the opposite pattern. No strong links between phytoplankton community composition and abiotic factors (under-ice convective mixing, snow on ice, under-ice light) were found. We suggest that inter-species relationships and more precise indicators of under-ice light should be considered to better understand under-ice processes.
Type IV Radio Bursts and Associated Active Regions in Sunspot Cycle 24
Authors: Kumari Anshu
Published: July 2022

We study the association of solar Type IV radio bursts with the location of active regions on the Sun during Solar Cycle 24. The active regions associated with moving and stationary Type IV bursts are categorized as close to disk center and far from disk center, based on their location on the solar surface (i.e. $\leq 45^{\circ}$
≤

45
∘

or $\geq 45^{\circ}$
≥

45
∘

, respectively). The location of active regions associated with Type IV bursts accompanied with coronal mass ejections (CMEs) are also studied. We found that ≈ 30 – 40% of the active regions are located far from disk center for all the bursts. However, it is found that most of the active regions associated with stationary Type IV bursts are close to disk center (≈ 60 – 70%). The active regions associated with moving Type IV bursts are more evenly distributed across the surface, i.e. $\approx 56 \%$
≈
56
%
and $\approx 44 \%$
≈
44
%
, close to disk center and far from disk center, respectively. The fact that most of the bursts have active regions close to disk center indicates that these bursts can be used to obtain physical properties such as electron density and magnetic fields of the CMEs responsible for geomagnetic storms.
How Does an Authoritarian State Co-opt Its Social Scientists Studying Civil Society?
Authors: Ma Ji
Published: July 2022

What channels can an authoritarian state employ to steer social science research towards topics preferred by the regime? I researched the Chinese coauthor network of civil society studies, examining 14,088 researchers and their peer-reviewed journal articles published between 1998 and 2018. Models with individual and time fixed-effects reveal that scholars at the center of the network closely follow the narratives of the state’s policy plans and could serve as effective state agents. However, those academics who connect different intellectual communities tend to pursue novel ideas deviating from the official narratives. Funding is an ineffective direct means for co-opting individual scholars, possibly because it is routed through institutions. Combining these findings, this study proposes a preliminary formation ofauthoritarian knowledge regimethat consists of (1) the state’s official narrative, (2) institutionalized state sponsorship, (3) co-opted intellectuals centrally embedded in scholarly networks, and (4) intellectual brokers as sources of novel ideas.
Congenital Splenic Cyst; Video Case Presentation and Literature Review
Authors: Mutlu Sütcüoğlu Bengü , Karabacak Onur
Published: July 2022

Congenital splenic cysts have been reported to usually regress spontaneously within a few months postnatally. A splenic cyst was detected in the ultrasonography of a 27-year-old pregnant woman at her 34th week of gestation. The size of the splenic cyst remained constant in the follow-up of the patient. In the ultrasonography performed in the postnatal 1st year, it was determined that the cyst persisted and remained the same size. There is no algorithm for the follow up of cysts in the literature, and information about congenital splenic cysts will be presented in this case report and review.
La pandemia diabete in Italia
Authors: Bonora Enzo
Published: July 2022

Sommario

In Italia vivono circa 4 milioni di persone con il diabete e ogni anno ci sono circa 350 mila nuove diagnosi. Le persone con diabete ricevono prescrizioni di farmaci, esami di laboratorio e strumentali e richiedono ricoveri ospedalieri più spesso delle persone senza il diabete. Il diabete è gravato da aumentata mortalità e accorcia la vita, soprattutto nelle persone di media età. La qualità della cura nelle persone con diabete è subottimale, soprattutto fra chi non è assistito nei centri diabetologici (che, peraltro, rappresentano dei luoghi “salvavita”). Il diabete contribuisce fortemente alla spesa sanitaria e comporta ingenti spese, non tutte specificamente sanitarie. Nonostante tutto questo e nonostante leggi nazionali e regionali, documenti di indirizzo nazionali e regionali, PDTA regionali e locali, promesse e proponimenti di varia provenienza, la pandemia diabete non riceve le attenzioni che merita.
Leber Hereditary Optic Neuropathy in Southwestern Ontario: A Growing List of Mutations
Authors: McDonald Heather M. , Sadikovic Bekim , Sheldon Claire A. , Bursztyn Lulu L.C.D.
Published: July 2022

Background:

Leber hereditary optic neuropathy (LHON) is a rare but bilaterally blinding disease. Three characteristic disease-causing point mutations, and other less common mutations, are most often found on the mitochondrially encoded genes of NADH-ubiquinone oxidoreductase core subunits (MT-ND). The purpose of this study is to provide an overview of LHON mutations in Southwestern Ontario and to describe the associated demographic and clinical characteristics.

Methods:

A retrospective genetic and clinical chart review was performed from January 2015 to 2020. Patients were identified within a mitochondrial mutation database and included if a mutation was detected on the MT-ND1, -ND4, or -ND6 genes. A clinical chart review was done on all available patients.

Results:

Forty-five of 63 patients identified had classic disease-causing mutations (6.7% m.3460G>A, 44.4% m.11778G>A, and 48.9% m.14484T>C). Several of the remaining 18 patients had rare mutations previously documented in association with LHON. Of the 14 patients with clinical charts accessible for review, 12 had symptomatic disease, and all but one had bilateral optic neuropathies. Nine patients had classic LHON mutations and 3 had possible novel mutations; 7 were males; 9 had final visual acuity ≤ 20/200 in at least one eye; and 6 of those had ≤20/400 in both eyes.

Conclusions:

This study adds to the literature on LHON in Canada, and specifically Southwestern Ontario. The demographic and clinical data regarding LHON in this geographic location, as well as possible novel disease-causing mutations, provide important information to aid clinicians in recognizing cases of LHON that may otherwise be disregarded.
Freedom of Commercial Expression and Public Health Protection at the European Court of Human Rights
Authors: Dzehtsiarou Kanstantsin , Garde Amandine
Published: July 2022

This contribution considers the case law of European Court of Human Rights (ECtHR) and focuses on the extent to which the Contracting Parties to the European Convention on Human Rights (ECHR) can regulate the tobacco, alcohol, and food industries in a manner compatible with their ECHR obligations. After briefly presenting the two key cases dealing specifically with tobacco advertising, this contribution considers the main factors that the ECtHR takes into account when balancing competing concerns, and in particular freedom of commercial expression and public health protection. It concludes that none of these factors is absolute, as the Court considers the strength of each one of them on the facts of each case. Nevertheless, it is clear from its case law that States have a wide margin of appreciation to regulate marketing practices that are inimical to public health and the prevention of non-communicable diseases more specifically, to the extent that even extensive advertising restrictions can be compatible with Article 10 of the ECHR.
Optimizing Ethics Engagement in Research: Learning from the Ethical Complexities of Studying Opioid Use in Pregnancy
Authors: Shah Seema K. , Gross Marielle , Nebeker Camille
Published: July 2022

Research on opioid use in pregnancy is critically important to understand how the opioid epidemic has affected a generation of children, but also raises significant ethical and legal challenges. Embedded ethicists can help to fill the gaps in ethics oversight for such research, but further guidance is needed to help strike the balance between integration and independence.
COVID-19 Law Lab: Building Strong Legal Evidence
Authors: Aneja Kashish , Ginsbach Katherine , Gottschalk Katie , Halabi Sam , Nardi Francesca
Published: July 2022

The COVID-19 Law Lab platform enables quantitative representation of epidemic law and policies in a given country for multiple years, enabling governments and researchers to compare countries, and learn about the impacts and drivers of policy choices. The Law Lab initiative is designed to address the urgent need for quality legal information to support the study of how law and policy can be used to effectively manage this, and future, pandemic(s).
The role of CFD in aerodynamics, off-design
Authors: Spalart P. R. , Bogue D. R.
Published: July 2022

We discuss the status, trends and long-term ambitions of Computational Fluid Dynamics (CFD) when applied away from the design point or concept, and therefore in the historically weak areas of CFD. This includes both undesirable flight conditions, such as stall, and undesirable products of the flow, such as noise. All pose the great challenge of turbulence, and accuracy is as dependent on the ideas behind the turbulence treatment as it is on computing power. A measured shift from Reynolds-averaged representations to large-eddy simulations will take place. Empiricism, both turbulence and engineering related, will recede only step by step over many years. Yet, CFD will make full use of every increase in computer power of this century. Increasingly, CFD will compete with flight tests, not just with wind tunnels, and will be validated by flight tests. Integration with other disciplines will allow us to predict crucial phenomena such as flutter, sonic fatigue, and pilot-induced oscillations. A gap will remain at any time between the phenomena amenable to a ‘grand challenge’ calculation and those amenable to a fully CFD-based design process, because certification involves thousands of conditions. The highest demand currently is in community and cabin noise for which industrial-accuracy methods are non-existent. On the other hand, gratifying progress has occurred in the area of stall and spin.
The future of rotorcraft
Authors: Byham G. M.
Published: July 2022

In writing this essay on rotorcraft I have chosen to confine my interests to the flying machines themselves, their development and the pressures that are shaping their future.
Vortices, sound and flames — a damaging combination
Authors: Dowling A. P.
Published: July 2022

The interaction between vortices, sound and combustion can lead to self-excited oscillations of such large amplitudes that structural damage is done. These occur because any small unsteadiness in the rate of combustion is a source of sound, generating pressure and velocity fluctuations. However, the velocity fluctuations perturb the flame, thereby altering the instantaneous rate of heat release. Instability is then possible because while acoustic waves perturb the combustion, the unsteady combustion generates yet more sound! Combustion oscillations can occur in afterburners and at idle in conventional aeroengine combustors. Lean premixed, prevapourised technology has tremendous potential to reduce NOxemissions, but is proving highly susceptible to self-excited oscillations. An overview of the physics of the interaction between vortices, sound and flames is presented, and illustrated by examples of instability in generic premixed ducted flames and in aeroengine combustors. The potential for both passive and active control is discussed.
Investigation of the upstream end effect on the flow characteristics of yawed circular cylinders
Authors: Gatto A. , Ahmed N. A. , Archer R. D.
Published: July 2022

The flow over a yawed circular cylinders is a research area of current interest in aerodynamics due to the inherent similarities with that of the swept wing configuration. These models however, must be carefully mounted in order to suppress a phenomenon known as attachment line contamination. This contamination occurs when models span the entire test section width, exposing the flow to the highly disruptive test section wall turbulent boundary layers. One way of suppressing this phenomenon is to mount the upstream end of the model off the test section wall, whereby eliminating the interaction between the boundary layer and the model. Mounting the model with the upstream end free of the wall however, introduces end effects which are transported inboard from the downwash over the free end.
Future SST engines with particular reference to Olympus 593 evolution and Concorde experience
Authors: Calder P. H. , Gupta P. C.
Published: July 2022

As the result of over a decade of intensive Anglo-French effort on both the airframe and the powerplant, the Concorde supersonic transport has completed its development and has convincingly demonstrated its ability to cross the Atlantic non-stop at Mach 2·0 with a full payload.

This represents a major milestone in the evolution of aviation where increases in speed and reduction of journey times have always attracted traffic. It also represents a major break-through in reducing passenger travel fatigue as has been demonstrated to a large number of people during the recent route-proving trials.
Aerodynamics
Authors: Haines A. B.
Published: July 2022

This Convention poses a challenge to the lecturers. It asks us to gaze into a crystal ball and to forecast the future on the basis of the research of today. My contribution is to review the aerodynamics scene. I am the first specialist lecturer; this is perhaps a recognition that many of the significant advances of the past have been aerodynamically inspired. It is natural to start by thinking back 20 years and asking whether we would then have predicted what has come true today. In aerodynamics, there is obviously a clear answer to this question.
The problem of certifying helicopters for flight in icing conditions
Authors: Lake H. B. , Bradley J.
Published: July 2022

The idea of this pair of lectures is to give some idea of the problems which face an official organisation when it is given the task and the responsibility of making recommendations to allow a helicopter to operate in icing conditions. The principles of the problems are not new— they will be recognised by all quality assurance people, from those who have to vet the design of the Severn Bridge to those who have to certify the safety of a new dog food. We are engaged on another chapter of the everlasting question: how do we define the environment; how do we find the test condition; and, how do we interpolate or extrapolate from what we have tested to what will be found by the operator?
The initial roll-up of a thick, two-dimensional wake behind a wing of finite span
Authors: Portnoy H.
Published: July 2022

Many investigators have studied the rolling-up of the vortex wake behind a wing of finite span. The earliest step in this study was the work of Kaden who found an analytical solution for the rolling-up with time of a semi-infinite, straight, two-dimensional vortex sheet. This solution must represent the situation very close to the edges of a finite-span vortex sheet of zero thickness, in two or three dimensions, during the initial stage of the rolling-up process. An important result following from Kaden’s work is that, from the very onset of rolling-up, due to the infinite velocity at the sheet edge, a spiral of near-axi-symmetric form, with an infinite number of turns, is established at the edge. This is a consequence of the assumption of zero thickness for the sheet.
“Errors due to pulsation in orifice meters” Comments on the paper by J. Grimson and N. Hay
Authors: Jeffery B. J.
Published: July 2022

The technical note “Errors due to Pulsation in Orifice Meters” by J. Grimson and N. Hay in the April 1971 issue of the Aeronautical Journal adds some welcome data to a field in which there is insufficient experimental evidence from which an explanation of the characteristics of orifice meters operating under pulsating flow conditions might be obtained.
The farmers' point of view
Authors: Huntington F. P. H.
Published: July 2022

It is with some trepidation that I face an audience with so large a combined technical knowledge and experience of agricultural aviation. When one considers the relationship between the agricultural contractor using aircraft for his work and the farmer, it is clear to me, that we, as the end users, play a relatively small part, all be it a vital one, in the total operation. An operation which clearly requires a high degree of technical skill, exacting safety standards and a high degree of accuracy; backed by high capital investment, sound salesmanship and strict management control.
The farmers' point of view
Authors: Walgate J. R.
Published: July 2022

When I first became interested in the field of agricultural aviation, I thought I had better find someone who had a thorough knowledge, backed up by a great amount of practical experience; so I sought the help of Ron Amsden, who, I am sure, most of you will have heard of. This was about four years ago.

Sometime during last summer, I was asked by Ron Amsden if I would be interested in attending a get-together of interested people on the subject of agricultural aviation and its problems. I had little idea then, that I should be called upon to give my views to such a distinguished gathering of experts. However, in my short experience of agricultural flying, I have gained some useful experience as a pilot and also a good understanding of the problems that arise out of this work.
Contributions of the Bell Helicopter Company to helicopter development
Authors: Kelley Bartram
Published: July 2022

It is a great privilege for me to give the Twelfth Cierva Memorial Lecture. The title, which was suggested by the Society, might imply a mere recitation of past deeds. This would hardly be a fitting tribute to a great inventor like Cierva. Such men are usually impatient with the past and eager to explore the future. Accordingly I will deal with Bell's history as briefly as possible, and then discuss some aspects of helicopter rotor systems which have recently come to light.
Remarks on Pontryagin's Maximum Principle applied to a structural optimisation problem
Authors: Boykin W. H. , Sierakowski R. L.
Published: July 2022

In a recent publication, Professor L. Dixon applied to a structural optimisation problem elements of the Pontryagin theory of optimal processes; well known in control systems. The problem considered was that of the minimum deflection of a cantilever beam under its own weight with constraints on the geometry. Digital and hybrid solutions of the two point boundary value problem arising from the optimisation problem were presented. Significant differences in the digital and hybrid solutions by the hill-climbing method were found. The present authors have examined the numerical methods for solving the optimisation equations, have developed a computing method which does not have the inherent convergence problem of the methods of Dixon, have re-examined the governing equation, and have noted a correction to these equations.
All weather operations—present achievements
Authors: Smith K. W.
Published: July 2022

When I was invited to address this distinguished gathering on the subject of All-Weather Operations it was with some trepidation that I accepted. It always strikes me that, to an audience the majority of whose members are not directly involved in furthering the cause of bad weather landing, yet another progress report on this topic must sound rather like the Continuing Story of Peyton Place—a complex intrigue of interwoven plots with little defined end result. I personally do not believe that the situation is really as depressing as this, and my task is to try and convince you that this is so, hopefully, by presenting objectives and achievements in simple terms. I will try (not completely successfully I fear) to avoid the plethora of jargon that the international civil aviation fraternity has necessarily had to employ in its complex debate and arguments. If, as a result, I can be accused of oversimplification, I apologise to the experts, and only hope that it is of genuine assistance to the non-experts.
Aircraft tyres—an analysis of performance and development criteria for the 70s
Authors: Clifton R. G. , Leonard J. L.
Published: July 2022

In this paper the many aspects of tyre performance criteria are discussed, as they have developed over the last decade. The corresponding tyre developments that have been effected to date are set out in considerable detail, together with the forward developments which are currently engaging the skills of modern tyre designers.

For the most part the paper deals with the present standard aircraft tyre, of conventional or cross-ply construction (Fig. 1), but the future role of the radial ply tyre (Fig. 2) is treated in some detail.
Theoretical velocity distributions downstream of non-uniform single and multiple smoothing screens
Authors: Jackson N. A.
Published: July 2022

Smoothing screens are frequently used in wind tunnels and other ducts to minimise irregularities in velocity profiles and reduce turbulence.

There is an optimum value for the screen pressure drop coefficient which, for wire gauzes, corresponds to an open area ratio less than 0·5 if only one screen is used. However, screens with open area ratios of about 0·5 or lower, produce lateral non-uniformities in the downstream flow due to jet coalescence. To avoid coalescence, two or more relatively open screens may be used in succession, either so close as to behave more or less as a single screen or more spaced out with each screen operating independently. It is the latter situation which is considered in detail in this note.

Because of inevitable manufacturing tolerances there will always be errors in the characteristic screen parameters, which will make the screen impose its own irregularities on the downstream flow.
An end to aircraft noise?
Authors: Dawson L. G. , Sills T. D.
Published: July 2022

Everyone agrees that the noise from aircraft has become an unreasonable nuisance to people living around airports. Because of it aviation is now extremely unpopular in some quarters and there is energetic public resistance both to the extension of existing airports and to the creation of new ones. The restriction on night take-off of jet aircraft from London airport is another illustration of the problem. This public attitude is understandable and it is tending to obscure the fact that transport aviation has made a great contribution to improving the quality of life. Taking one small example, without aviation the package tour holiday, which represents good value for money, would hardly be possible.

The purpose of this paper is to take the advantages of aviation for granted and to explain that it is technically feasible to build a subsonic aircraft and engine combination quiet enough not to annoy the public.
Pilcher and the multiplane—A neglected aspect of a pioneer's work
Authors: Jarrett Philip
Published: July 2022

“A little onward lend thy guiding hand

To these dark steps, a little further on;”

Milton - Samson Agonistes, 1671

It is suggested that those wishing to familiarise themselves with the general history of Pitcher's work consult “Aviation” by C. H. Gibbs-Smith, HMSO, 1970, pages 85-90, and items 1 and 2 in the references at the end of this paper, although it should be remembered that this paper amends some of the information contained in these sources.

When dealing with famous men in history, perhaps one of the most persistent and difficult questions is that of their relative importance. It is very easy, in a bout of enthusiasm or contempt, to over- or underestimate the influence that a person may have had upon his contemporaries. This applies no less in aeronautics than elsewhere. The example of Percy Sinclair Pilcher (Fig. 1), the British gliding pioneer, is a case in point.
“Supersonic” flow in the animal world
Authors: Black Joseph
Published: July 2022

The analogy between the formation of large amplitude waves (hydraulic jumps) on the surface of shallow flowing water, and shock waves in supersonic air flow is well-known. In addition to the correspondence between the wave patterns the variation in water depth can be related to the pressure distribution.

This “hydraulic analogy” is usually demonstrated in the laboratory in a tank which produces a shallow flow of water over a horizontal surface, on which the appropriately shaped body is mounted. The resulting stationary wave patterns may then be examined. Fig. 1 shows a typical bow-wave on a double-wedge.
Air transport development between the UK and Europe—the next twenty years
Authors: Wilkinson K. G.
Published: July 2022

This invitation to lecture to the Swindon Branch of the Society coincided with a period of crisis and change in the air transport industry where events stemming from growth, new technology, commercial challenge and political action were bringing about unprecedented ferment. Admittedly it could be said that the manufacturing industry has known this condition continuously for 20 years. But whereas the manufacturing industry has run into problems arising from retrenchment in military procurement, there is no sign that commercial air transport will do other in the long term than continue to expand. The main question is, what is the most beneficial nature of the expansion? A correct analysis of the present situation is important to the transport industry and also to the design and manufacturing organisations that are interested in building aircraft to meet the needs of the expansion ahead.
Air Transport Group
Authors: Brewer George F.
Published: July 2022

A favourite device of lecturers is to take a key word in the title of their speech and quote its definition from the pages of Webster's dictionary. Even though this may be mildly insulting to the audience—especially if the word being defined is something simple like “aviation”—it immediately gets the listeners onto the same track with the speaker. If nothing else, it proves the speaker at least knows how to spellthe key word in his speech and establishes his credentials as an expert in the field being discussed.

I would like to show you how informed I am by starting with a Webster's dictionary definition of “general aviation”, the key element in my speech title. Unfortunately, I cannot find it in my dictionary, and I doubt if you can find it in your Oxford dictionary. In the eyes of the lexicographers, “general aviation” simply does not exist. But you and I know it doesexist, and I would still like to start with a definition of it.
Historical Group
Authors: Beamont R. P.
Published: July 2022

Much has been said and written about the last-minute preparation of the Royal Air Force for war after Munich, and of how disaster was so narrowly averted by inspired activity to produce fighters and train fighter pilots. Albeit there was more than a little luck on our side in the inability of the enemy to exploit a unique opportunity to attack this country immediately upon the outbreak of war in September 1939. We really were too weak to have stopped them at that time.

We were not only unprepared in numbers, but also to some extent in terms of tactical thinking and training. One of my earliest recollections of the Service was finding with something of a shock that as a newcomer, and at 18 scarcely more than a schoolboy, I had different ideas about the tactical use of fighters to those being taught at the time.
Wind tunnel interference in dynamic measurements
Authors: Molyneux W. Q.
Published: July 2022

The main object of tests on models in wind tunnels is to obtain results of direct application to aircraft in flight. Unfortunately, the flow about a model in a wind tunnel is subject to constraints that are absent in flight, and so allowance must be made for these wind tunnel interference effects for the results to be meaningful.

There is a considerable body of information on the sources of wind tunnel interference and, so far as effects in steady flow are concerned, methods of estimating the corrections to be applied are generally available. They enable results of wind tunnel tests to be reduced to equivalent flight results with some measure of confidence. The situation is far less satisfactory for oscillating models. The additional interference effects due to frequency of the motion may be of too complex a nature or require too tedious a computation (particularly for a deforming model) for a reliable reduction of the results to flight conditions to be practicable.
Energy flow diagrams
Authors: Le Claire R.
Published: July 2022

Although the concepts of “efficiency” or “coefficient of performance” are useful in relating the output to input energies of a system, they do not give any indication of the manner in which this input energy varies within the system.

This shortcoming may be overcome by using “energy flow diagrams” which have the great advantage of providing a pictorial, yet mathematically accurate, representation of the energy balance of the system, from which an overall appreciation of the energy variations can be obtained at a glance.
The state of the art in remote sensing from space
Authors: Simmons N.
Published: July 2022

In many disciplines, cartography included, it is a requirement to discover or to measure what is on or in the Earth. Detailed investigation on the surface by itself is clearly non-optimum, for logistic and other reasons. Even in Roman times, when labour was cheap, it is learned that mineral deposits in this country were located by observation from high ground of places where the early morning frost first cleared under the rising sun; presumably this was followed up by detailed work on the identified spots.
Air Law Group
Authors: Cheng Bin
Published: July 2022

The Convention for the Suppression of Unlawful Seizure of Aircraft—to give the treaty its official title—was drafted by a subcommittee of the Legal Committee of the International Civil Aviation Organisation (ICAO) in September/October 1969, considered by the Legal Committee itself in February/March 1970, signed at a diplomatic conference meeting at The Hague on 16th December 1970, and came into force on 14th October 1971 amongst those States that had ratified it. While the coming into being of the Hague Convention has been fairly expeditious, so far only 15 States (Bulgaria, Costa Rica, Ecuador, Gabon, Hungary, Israel, Japan, Jordan, Mali, Niger, Norway, Sweden, Switzerland, USA, USSR) have accepted it. It is to be hoped that the United Kingdom, which took a leading part in developing this Convention, will do so before long, especially as the necessary legis-lation has already been passed—the Hijacking-Act which received the Royal Assent on 5th August 1971.
The induced drag on a rolling wing
Authors: Hancock G. J.
Published: July 2022

In a recent paper Garner discusses, among other topics, the induced (inviscid) drag or lift dependent drag, on finite wings which have effective antisymmetric incidence distributions. One example concerns a finite wing whose incidence varies linearly in the spanwise direction as

This wing experiences an overall induced drag which is made up from two contributions.
Engines for civil V/STOL
Authors: White E. A. , Wilde G. L.
Published: July 2022

The rising demand for short-haul air transport with its attendant problems of community disturbance, airport congestion and increasingly longer total journey times is well recognised in many parts of the world. Equally accepted is the need for a radically new solution to these problems with a major V/STOL transport sub-system which can both be integrated with operations at existing airports and extended as necessary to new airports in urban areas without sterilising large areas of real-estate. All this has been argued at great length many times in many places and there have been many “solutions in search of the problem”. This paper reviews some of the possibilities from the engine manufacturers’ point of view without commenting on the relative merits of rival aircraft proposals.
UK aerospace—a personal view
Authors: Edwards George
Published: July 2022

In the first Henry Tizard Memorial Lecture presentee here at Boscombe Down on the 28th October 1964, Professor R. V. Jones gave a masterly survey of the life and times of Sir Henry, as one who knew him well and it will be no part of my plan to retrace the story of this great man tonight.

While re-reading Jones’ paper I was reminded of the men of stature who were around in the aviation business in the years immediately before the Second World War. It was one of Henry Tizard's great tasks to harness these giants at a time when this country led the world in scientific research.

I, personally, had little to do with Tizard as in those days my job was to carry the bags for those who had the message to convey. This in no way detracts from my admiration of him as a quite outstanding person and a rare example of a real scientist who understood the practical problems associated with the interpretation of new ideas.

It is a great honour for me to be asked to give this, the Sixth Henry Tizard Memorial Lecture.
Advances in helicopter avionics
Authors: Nethaway J. E.
Published: July 2022

When one attempts to define “advances in helicopter avionics” it is possible to do one of two things:

(a) either describe in some depth the development of one particular aspect of helicopter avionics, or

(b) illustrate the broader impact of avionics on the increased use of helicopters in general.

In the present context the latter appears to be the more important because otherwise it is possible to give the misleading impression that helicopter avionics is a limited or narrow field, as it was in the past, whereas it is very wide and covers the whole spectrum of helicopter operations. The importance of avionics can hardly be over emphasised because in many ways avionics transforms the basic helicopter attributes of vertical flight and flexibility, and the continued development of helicopter avionics will be inevitable. It will also be inevitable because, in order to survive, our forces must continually improve their operational capabilities and avionics developments can allow them to do so. Now the most rapid advances in helicopter avionics may be achieved by adapting fixedwing aircraft technology although there are situations where entirely new techniques are called for. In any event the primary task is one of defining and tailoring equipment to the helicopter and its environment.
The application of nodal stress concepts to the bending of plates and shells
Authors: Jobson D. A.
Published: July 2022

When a continuum is represented in lumped terms as a set of nodes which are regularly connected in a specified sense, the state of stress at each interior node may be inferred from the forces which act on it. These ideas require some extension for plates and shells, whose flexure and twisting is basically governed by the Love-Kirchhoff hypothesis. The latter requires that the mid-plane stresses be combined with bending and torsional stress couples acting on interfaces perpendicular to the mid-plane.
The Effect of Static Deflection on the Harmonic Resonance of a System with a Hardening Non-Linear Spring
Authors: Reif Z. F.
Published: July 2022

In a vibrating system with a non-linear restoring force the effect of gravity, if it influences the equilibrium of motion, is not completely balanced by the static deflection force. This produces in most cases an increase of the magnitude of non-linearity because of the displacement of the static equilibrium point on the restoring force characteristic. The static deflection parameter thus offers a more complete definition of this effect and is consequently used in the vibration equation in preference to the force of gravity. Previous investigation of the free vibration indicates that the existence of a static deflection must result in considerable changes of the forced vibration response.
Sea Dart
Authors: Bridle G. W.
Published: July 2022

The subject of management techniques needs to cover a wider field than the rather narrow interpretation given in much current discussion of its tools. To cover the relevant area, it is intended to use the managerial concepts pioneered by the Frenchman—Henri Fayol. Fayol suggested management activity is made up of five parts:

Planning

Organising

Commanding

Co-ordinating

Controlling

The machinery used for the management of the development of the Sea Dart missile will be reviewed under those five parts.
Project Management Techniques of Rapier
Authors: King G. E.
Published: July 2022

The Rapier project began to emerge shortly after the publication of the report of the committee which sat under Sir Solly Zuckerman to consider the management and control of Research and Development. The “Zuckerman” formula was applied to Rapier and feasibility studies were followed by a project study, a holding contract, and eventually full development.

Meanwhile another committee under Mr. W. G. Downey had been considering the management of large development projects, and some of the techniques advocated by them have already been applied to Rapier.

Rapier, therefore, can be said to span the Zuckerman-Downey period, a period which has seen modern management techniques applied in more and more depth throughout the aerospace industry.
Shock Tunnel Operation with an Expansive Area Change at the Main Diaphragm
Authors: Gore M. M. , Stalker R. J.
Published: July 2022

The use of an expansive area change immediately following the diaphragm has afforded considerable convenience in shock tube applications and has been studied by a number of authors. It allows the use of a smaller diaphragm, thereby reducing the disturbance to the shock tube flow caused by the diaphragm opening, and it also permits greater flexibility in the choice of driver section configurations for a given shock tube size.

It is natural to consider the extension of this idea to shock tunnel operation. This has been encouraged by the possibility of applying area change to operation of an arc-driven shock-tunnel. Some early success in employing arc-heated drivers for shock tunnels has been reported by Warren et al. However, the configuration they studied employed a long driver section to achieve correspondingly long test times. In addition, to achieve a constant shock velocity it was necesssary that electrical energy was added so that the gas was heated uniformly before the diaphragm ruptured. This necessitated a fast discharge condenser bank, with a high discharge voltage, the latter to enable an arc to be sustained over the length of the driver section. In the present application, a constriction between the driver section and the shock tube is employed, allowing the driver section to be treated as a constant pressure reservoir of gas. It is anticipated that this will allow the use of shorter drivers, thereby permitting the adoption of lower discharge voltages, and will also allow energy to be added relatively slowly while the shock tunnel is operating. This will produce substantial economies in provision of the large energy storage facilities required for shock-tunnel operation.
Reinforced Circular Holes in Cylindrical Shells
Authors: Rao K. P. , Davies G. A. O.
Published: July 2022

The analysis of a cylindrical shell with cut-outs, which are reinforced to reduce the stress concentrations, is of importance in many engineering fields, particularly in aircraft structures. The most common assumptions made are that the curvature effect is negligible and that the reinforcement is a compact flexible bead. In the analysis of holes in fuselage shells the neglect of the effect of curvature may lead to serious errors as shown theoretically by Lurie and Vandyke and experimentally by Houghton and Rothwell. In some cases the bending stresses are of the same order as the membrane stresses which themselves may be much higher than the flat plate solution. Lurie obtained a perturbation solution for an unreinforced hole by expanding in powers of curvature parameter β, the results being valid for small values of β. Vandyke extended this solution up to β=4 by using a collocation procedure. In fact, if the collocation method is used it seems possible to obtain a convergent series solution for any β, the only limitations being the shallowness of the shell and the restriction that the deflections are not large.
Use of an Altitude Test Facility in Engine Development
Authors: Hartley R. M. , Boal J.
Published: July 2022

The first three papers of this all-day symposium, held on 20th November 1969, were published in the March issue of the JOURNAL. The final papers and the discussion are printed below.

It can be said that the main cause of premature failure or malfunction of any engineering component is attributable to the design being below the standard required for the environment in which it had to exist. This idea is neither surprising nor new, and applies throughout the whole field of engineering, especially in the aircraft industry which is extremely conscious of the need to design and develop its systems to suit the environmental conditions of flight.

In the air-breathing engine industry this need has been recognised almost from the inception of flight. For the successful development of an aero engine there is, therefore, the need to use all the resources of past flight experience to provide initial design information for the engine and its components, and then to test the engine or components to determine that the requirements have been fulfilled.
The History of the Avro Vulcan
Authors: Davies S. D.
Published: July 2022

The series of Chadwick Memorial Lectures was started in 1956 by Harold Rogerson who gave a very complete picture of Roy Chadwick's life and experience as an aircraft designer. Since then lectures in this series have mainly concerned problems on future projects, which would certainly have excited his lively interest, rather than nostalgic reviews of the past.

However, when I was honoured by being asked to give the 14th Lecture of the series it occurred to me that nothing would be more appropriate than a paper on the History of the Vulcan, since it was not only a major Avro enterprise in its own right, but it was also the last project with which Roy Chadwick was intimately concerned. It had a peculiar fascination for him, because he had, all the time I knew him, an enthusiasm for the all-wing transport as the ultimate in aerodynamic and structural efficiency
Recent Progress in All-Weather Landing Techniques
Authors: Craig D. K.
Published: July 2022

When Mr. McManus and I first agreed to give this lecture, we did not realise that the audience would be likely to contain so many pilots. It could be construed that our job is to automate pilots out of business. However, I wish to assure you all that this is far from the truth. Our job is to completely automate the whole flight envelope so that pilots become “Systems Managers”. The result will be more accurate, reliable and safe flying, with the pilot assuming manual control on a minimum number of occasions consistent with keeping in practice.