bluuebunny/crossref_metadata_2025_split huggingface dataset:
Triticale out-performs wheat on range of UK soils with a similar nitrogen requirement
Authors: ROQUES S. E. , KINDRED D. R. , CLARKE S. 
Published: August 2016

SUMMARYTriticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.
Effectiveness of 3 per cent boric acid in 70 per cent alcohol versus 1 per cent clotrimazole solution in otomycosis patients: a randomised, controlled trial
Authors: Romsaithong S , Tomanakan K , Tangsawad W , Thanaviratananich S 
Published: August 2016

AbstractObjectives:To compare the clinical effectiveness and adverse events for 3 per cent boric acid in 70 per cent alcohol versus 1 per cent clotrimazole solution in the treatment of otomycosis.Methods:A total of 120 otomycosis patients were randomly assigned to receive either 1 per cent clotrimazole solution (intervention group) or 3 per cent boric acid in 70 per cent alcohol (control group) at the Khon Kaen Hospital ENT out-patient department. Treatment effectiveness was determined based on the otomicroscopic absence of fungus one week after therapy, following a single application of treatment.Results:After 1 week of treatment, there were data for 109 participants, 54 in the clotrimazole group and 55 in the boric acid group. The absolute difference in cure rates between 1 per cent clotrimazole solution and 3 per cent boric acid in 70 per cent alcohol was 17.9 per cent (95 per cent confidence interval, 2.3 to 33.5; p = 0.028) and the number needed to treat was 6 (95 per cent confidence interval, 3.0 to 43.4). Adverse events for the two agents were comparable.Conclusion:One per cent clotrimazole solution is more effective than 3 per cent boric acid in 70 per cent alcohol for otomycosis treatment.
Aerodynamic Noise
Authors: Lilley G. M. 
Published: August 2016

The heading aerodynamic noise includes all cases where sound is generated by fluid flows. It includes aeolian harps, edge tones and related phenomena as well as vortex, boundary layer, wake and jet noise. In the strict sense it does not include propeller noise and the direct noise generated by; bodies in motion. However, in view of their importance as sources of aircraft noise some of their more important aspects will be discussed briefly and compared with the similar properties of pure aerodynamic noise.In general it is audible aerodynamic noise which is of major interest at present, but it would be unwise to neglect entirely the ultrasonic aspects. These have received little attention as yet.
Some Aspects of the Mechanical Properties, uses and Manipulation of Aluminium Alloys
Authors: Smith F. R. C. 
Published: August 2016

It may be said that the title of this paper covers too wide a scope to be dealt with satisfactorily in the time available and that as a consequence the treatment of each section will be of a sketchy nature.This is undoubtedly a justifiable criticism, particularly from the point of view of a specialist, but the aim has been to present what it is hoped will be helpful information of a practical nature to builders of aircraft rather than aero engines. There is no intention to enter deeply into the technical aspects of the applications of aluminium and its alloys to aircraft, but rather to review some of the many problems and enquiries which have been encountered during several years' contact with the aircraft industry.
Notes on Aero Engine Research
Authors: Rayner P. H. 
Published: August 2016

When the writer undertook the preparation of this paper, he rapidly discovered that it was not easy to find any branch of the subject which had not already been dealt with exhaustively by far abler pens than his. One or two matters have, however, been chosen about which information is somewhat meagre or scattered, and which may not, perhaps, be familiar to the aircraft engineer.First a review will be made of the various types of electronic engine indicator which have been developed up to the present time; this instrument is coming into prominence now, and although it has by no means reached a state of perfection, it is a valuable asset in the hands of the research engineer for the study of fuel problems and other minor points.
The Influence of Aircraft Gross Weight upon the Size and Weight of Hulls and Fuselages
Authors: Rosenthal L. W. 
Published: August 2016

In this paper an attempt has been made to trace the influence of gross weight, as the accepted measure of size, upon the dimensions of hulls and fuselages and from this, to evaluate the probable trend of the weights of these components with increasing gross weight.During the past few years the size and gross weight of aircraft have rapidly increased and there appears at the moment little, if any, structural limit upon the size and gross weights attainable, since it can be shown that the percentage weights of hulls and fuselages tend to decrease as size increases.
The General Theory of Cylindrical and Conical Tubes under Torsion and Bending Loads
Authors: Hadji-Argyris J. , Dunne P. C. 
Published: August 2016

In 3.2.1 it was indicated that ξi, ηi may be found from the appropriate co-factors of the secular equation and appear directly as functions of the geometric and elastic properties of the root cross-section. The method will be applied in 5.6.2 for the four-boom tube, in 5.7.3 for the n-boom tube, and in 5.8 for the trapezoidal tube with direct stress carrying top and bottom panels. This procedure is advantageous when it is desired to study the effect on ξ, η of varying particular parameters of the cross-section.However, when in any case the h-functions have to be obtained, it is often more expedient to determine ξ, η by one of the following procedures.
Relative Eddy and its Effects on the Performance of a Radial Bladed Centrifugal Impeller
Authors: Reddy K. R. 
Published: August 2016

SummaryMathematical and experimental methods for estimating the relative eddy velocity in a radial bladed impeller channel have been determined to replace the empirical velocity so far used in designing and predetermining the performance. The effect of this relative eddy velocity on rotor performance has been experimentally determined on a specially designed compressor and compared with mathematical calculation.
Determination of the Buckling Load of Struts with Successive Approximations
Authors: Ratzersdorfer J. 
Published: August 2016

In cases of tapered struts with hinged or built-in ends where the exact determination of the buckling load is complicated it may be useful to apply a method of successive approximations.Let us first consider a bar of the length l with hinged ends under the action
of the compressive force P. The differential equation of the bending line becomeswhere v is the deflection at the section u, v with the moment of inertia I (u) and E is Young's modulus. At the ends of the bar the deflection v is equal to zero (Fig. I).
Cascade Blade Flutter and Wake Excitation
Authors: Parry J. F. W. , Pearson H. 
Published: August 2016

A new method of presenting the aerodynamic data for a compressor or turbine blade cascade is shown, with particular reference to flutter excitation or damping. The application of these results to wake excitation is demonstrated.The basic equations for flutter excitation or damping are derived in the paper “The Aerodynamics of Compressor Blade Vibration” presented by H. Pearson at the 1953 Anglo-American Conference (London). No new equations are derived but the method of plotting the relevant data leads to a simpler appreciation of the criteria.
Influence of Recent Civil Airworthiness Requirements on Aircraft Design
Authors: Tye W. 
Published: August 2016

In preparing this lecture I found it necessary, when considering recent changes in aircraft design, constantly to ask myself the question “Is this particular change due to airworthiness requirements or does it arise from reasons other than airworthiness?” In fact, one must consider whether requirements have any influence at all on the development of trends in design. Should design be likened to a runaway horse with requirements following some way behind, or are requirements a strict rein by which the pace and direction of design is controlled?My own answer to these questions is that the pace at which development takes place is not influenced at all by airworthiness requirements, but that requirements help to prevent design from running off the path of safety. To carry the analogy a little farther, the faster the development is, the more difficult it is to keep it running on the path of safety.
Variable Distributed Loads in the Theorem of Three Moments
Authors: Turton F. J. 
Published: August 2016

The Theorem of Three Moments in a simple form, referring to bending moments at any three consecutive supports A, B, C, of a continuous beam uniform in each bay, AB = a, BG = c, takes the formw and being constant load intensities over AB and CB respectively.On p. 159, Vol. 42 (1938), of this journal, Capt. J. Morris discussed a modification in this case (and in the more general case when the beam is in thrust) when the load intensity varies according to a parabolic law.
Primary Instability of a Panel of Integral Construction with Unflanged Stiffeners
Authors: Yusuff Syed 
Published: August 2016

SummaryA theory of primary failure of compression panels of integral construction with unflanged stiffeners is presented, involving rotation, or translation, or rotation and translation of the stiffeners with the corresponding distortion of the sheet without deformation of the cross sections in their own planes. The investigation shows that the failure may occur generally either by pure torsion of the stiffener with the associated lateral distortion of the sheet or by pure flexure in accordance with whichever mode yields a smaller stress. The theory is compared with the test results covering a fairly wide range of the dimensions involved. The theory is in complete agreement with the experiments. The accuracy of the result thus obtained indicates that the fillets at the junction of the skin and the stiffener are not important and their effects may safely be disregarded.
Effects of Fuel Type on the Performance of Aero Gas Turbine Combustion Chambers, and the Influence of Design Features
Authors: Sharp J. G. 
Published: August 2016

SummaryThe performance of aero gas turbine combustion chambers is discussed under the following headings : Combustion efficiency, combustion stability, ease of ignition, deposits, exhaust temperature variation, and smooth combustion. It is shown that, as assessed by these criteria, combustion chamber performance can be significantly affected by fuel characteristics; also that the effects of fuel type can be greatly modified by equipment design changes. The conclusion is that most of the problems- aggravated by fuel characteristics are better solved by modifications to equipment, if fuel availability and cost are not to be adversely affected.
The Use of Dummies in the Camouflage of Operational Aerodromes
Authors: Yassin E. Z. 
Published: August 2016

Dummies are particularly suitable for use in camouflaging operational aerodromes; they not only serve to mask the aircraft and equipment stationed thereon, but also make it possible to give the flying field the aspect of being unusable for flying purposes.In recent wartime practice, dummies have been extensively used for aerodrome camouflage, and have proved particularly effective, since an enemy flying over the area in which an operational aerodrome is situated, will usually omit to take notice of dummies imitating local features of the landscape, and concealing the purpose for which the terrain is actually being used.
High Wing Loading and Some of Its Problems from the Pilot’s Point of View
Authors: Fraser H. P. 
Published: August 2016

It is indeed a very great honour for so new a member to be accorded the privilege of reading a paper before the Royal Aeronautical Society, and I would like to express my sincere thanks to the President and the Council of the Society for the invitation extended to me.We have heard from designers and experts in all branches of aeronautics what problems confront them and how they propose to solve them. I am going to discuss, from the point of view of a pilot, some of the problems that seem to me to arise from high performance and increased wing loadings, and to indicate what appear to me to be possible solutions. I propose to consider these problems under five headings :—
(1)Take-off.(2)Irreversible Aileron Control.(3)The Approach.(4)Flattening Out(5)Touching Down.
Some Economic Aspects of Transport Aeroplane Performance
Authors: Mentzer W. C. , Nourse Hal E. 
Published: August 2016

AbstractTotal air transport operating costs are divided into three general classifications : (1) Significant operating costs which are defined as those resulting from the flight of an aeroplane or those affected by variation of aeroplane size, power, initial cost, and aerodynamic efficiency. Equations for the development of significant costs are presented. (2) Passenger service costs which are defined as those which vary with the number of passengers aboard an aeroplane are enumerated. (3) Overhead costs in air transportation are also dwelled upon and it is concluded that these costs change their proportion to significant costs when the physical and performance characteristics of the aeroplane being considered change.The marked effect on significant cost of varying aeroplane utilisation is brought out. Utilisation is also shown to be chiefly a function of trip length, with block speed, seasonal schedule variation and other factors being secondary functions.The effect on significant cost of varying block speed either by increasing cruising power or improving aerodynamic efficiency is investigated for one type of transport aeroplane. Increased block speed obtained by increasing cruising power is found to increase significant cost very rapidly. Increased block speed obtained by improving aerodynamic efficiency is found to decrease significant cost appreciably and relatively large increases in aeroplane first cost are found to be justified if aerodynamic efficiency is improved. The adverse effect on significant cost of increasing trip length is investigated. The effect of changing specific fuel consumption is discussed.It is pointed out that economic factors apart from those associated with fundamental aeroplane design and performance, such as interior arrangement, safety records, competition and general economic conditions, play the major role in the economic outcome of air transportation.
The Calculation of the Loads and Bending Moments in Rigid Jointed Frames with Special Regard to Variation in Section of Members
Authors: Morris J. 
Published: August 2016

The main object of this paper is to put forward a routine method for taking acccount of the variation in section in the stressing of rigid jointed frames. The formulæ in general use which mainly apply to members of uniform section are suitably modified so as to be applicable to cases where members may be of variable section. The underlying feature of the method is to base the treatment of a rigid jointed frame on the properties of cantilevers loaded at their free ends. Certain deflection coefficients are involved and as shown may be found separately as required for each member. These coefficients may be computed either analytically or graphically. The importance of taking account of variation in section is brought out by practical examples. In certain cases it is shown that very considerable errors may arise if instead of having regard to the actual variable section a mean value is assumed as being sufficiently close from the point of view of the resulting loads. From experience already gained in the application of the method to an actual structure the labour involved is not much in excess of that for the case of the same structure with the sections averaged.The method does not take end load deflection effects into account and an extension of the method to do this seems desirable. There are, however, many cases in which end load deflection effects are not serious, and in any case it seems useful to have a solution in which these are neglected in the absence of means for obtaining a more comprehensive analysis.
Strength of Metals in the Light of Modern Physics
Authors: Gough H. J. , Wood W. A. 
Published: August 2016

SummaryThe strengths of the metals at present available to industry are of especial importance to the aeronautical engineer who is also in a position to appreciate the need for greatly improved materials, the absence of which often places restriction on much needed developments. Although the materials of the future may become available by the somewhat fortuitous development methods at present employed, it is undeniable that greatly accelerated developments would result if a correct understanding was obtained of the fundamental characteristics of the cohesion and fracture of metals, of which the former belongs to the field of the atomic physicist.It has been found possible, for the first time, to show that failure under static and fatigue stressing is associated with changes in the crystalline structure which are identical. These changes are (1) a dislocation of the initially perfect grains into large components which vary in orientation from that of the internal grain by amounts up to about 2°,(2) the formation of “crystallites,” approximately 10-4to 10-5cm. in size, whose orientation varies widely from that of the original grains, and (3) the presence of severe internal stresses in the crystallites. At fracture, whatever the type of applied stressing, the whole of the specimen behaves to the X-ray beam as a medium of crystallites showing marked lattice distortion and oriented completely at random. X-ray diffraction methods are shown to distinguish clearly between the effects of the application of safe and unsafe ranges of stress; the first method that has been successful in this respect.In order to show the relationship between the new work described and previous work dealing with the use of X-rays in studying the deformation characteristics of metals, a preliminary section of the paper deals with cold-rolling and drawing. A survey is also presented of the present position regarding strength and atomic structure, together with references to various theories regarding the imperfections of crystals as encountered in practice. An introductory section describes briefly the atomic structure of metals, as revealed by X-rays.
Metallurgical Problems of Aero Engine Manufacture
Authors: Gadd E. R. 
Published: August 2016

The modern internal combustion engine, particularly the power unit developed for aircraft propulsion, provides a subject of great metallurgical interest and speculation.The requirements of the aero engine designer for greater engine power while retaining a low weight/power ratio has inspired research into fuels of improved characteristics, and on the metallurgical side into materials of superior properties to those previously available.
Aerodrome Design
Authors: Norman Nigel 
Published: August 2016

The present paper is confined to matters concerned with the requirements for landing and take-off of aircraft at land aerodromes, that is to the landing area.In the selection of sites the questions that arise are size and over-all gradients. In development of a selected site account must be taken of directions of landing, dimensions of flightways or runways, local gradients or undulations, nature of surface. Finally, to ensure safety of flight the site must be protected by zoning.The subsequent problems of detailed layout, of civil engineering in construction, of control and equipment, and of design of administrative and terminal buildings, though susceptible of more popular treatment, come later in sequence. My first more detailed study is therefore devoted to what may be termed the aircraft's point of view as to what it would like in order to bring in and take out its load in the most economical manner.
New Results and Problems in Medical Stratosphere
Research
Authors: Strughold H. 
Published: August 2016

Flight is the most 'perfect and unconstrained form of animal motion; it is also the most widespread, since it offers the most favourable conditions of survival in the struggle for existence. Animal species losing the power of flight, are an easy prey for their enemies, and speedily become extinct.Man, having achieved the power of mechanical flight by technical skill, has now introduced the art of flying in his own struggle for existence, as abundantly proved by the history of the past thirty years. Research, and not engineering research alone, has stood in the forefront of this development: filling the rôle of the advanced reconnaissance unit in development, experimentation, and the tactical application of the power of flight.Man, aircraft-borne, now flies higher (record altitude 17,000 m.), faster (speed record 755 km./h.), and farther (long-range distance record over 12,000 km.), than any other animal. This raises a query as to the effect of flight on the human organism.
The Wing-Beat of Pigeon
Authors: Guidi G. 
Published: August 2016

RésuméAfter some general remarks upon the constant flight characteristics of birds belonging to any given species, the author describes his method of obtaining, approximately, a cinematographic reproduction of three geometrical projections of the wing-beat. Dealing with one particular case he determines the trajectory in space of a pigeon's wing tip during an entire beat, and, also, the speed and acceleration reached by it.
The Forces on an Aerofoil at Very Low Speeds
Authors: Thom A. , Swart P. 
Published: August 2016

SummaryThe forces on an aerofoil have been measured at various angles of incidence for 0.5 < R < 2,000.Below R = 2 the lift is found to be given approximately by :—L, = (3/2) µlV sin 2xand the drag at all angles of incidence tends to:D = µlV.An approximate theoretical estimate is also given of the effect of spacing, on the drag of a series of flat plates at R → o.