bluuebunny/crossref_metadata_2025 huggingface dataset:
TrkC Intracellular Signalling in the Brain Fear Network During the Formation of a Contextual Fear Memory
Authors: Silva Francisca , Masella Gianluca , Madeira Maria Francisca , Duarte Carlos B. , Santos Mónica
Published: March 2023

Learned fear is orchestrated by a brain fear network that comprises the amygdala, hippocampus and the medial prefrontal cortex. Synaptic plasticity within this network is critical for the formation of proper fear memories. Known for their role in the promotion of synaptic plasticity, neurotrophins position as obvious candidates in the regulation of fear processes. Indeed, recent evidence from our laboratory and others associates dysregulated signalling through neurotrophin-3 and its receptor TrkC with the pathophysiology of anxiety and fear-related disorders. Here, we put wild-type C57Bl/6J mice through a contextual fear conditioning paradigm in order to characterize TrkC activation and expression in the main brain regions involved in (learned) fear – amygdala, hippocampus, and prefrontal cortex – during the formation of a fear memory. We report an overall decreased activation of TrkC in the fear network during fear consolidation and reconsolidation. During reconsolidation, hippocampal TrkC downregulation was accompanied by a decrease in the expression and activation of Erk, a critical signalling pathway in fear conditioning. Moreover, we did not find evidence that the observed decrease of TrkC activation was caused by altered expression of dominant negative form of TrkC, neurotrophin-3, or the PTP1B phosphatase. Our results indicate hippocampal TrkC inactivation through Erk signalling as a potential mechanism in the regulation of contextual fear memory formation.
High-performance flexible all-solid-state asymmetric supercapacitors based on binder-free MXene/cellulose nanofiber anode and carbon cloth/polyaniline cathode
Authors: Bi Xiaoyu , Li Meichun , Zhou Guoqiang , Liu Chaozheng , Huang Runzhou , Shi Yang , Xu Ben Bin , Guo Zhanhu , Fan Wei , Algadi Hassan , Ge Shengbo
Published: March 2023

The search for wearable electronics has been attracted great efforts, and there is an ever-growing demand for all-solid-state flexible energy storage devices. However, it is a challenge to obtain both positive and negative electrodes with excellent mechanical strength and match positive and negative charges to achieve high energy densities and operate voltages to satisfy practical application requirements. Here, flexible MXene (Ti3C2Tx)/cellulose nanofiber (CNF) composite film negative electrodes (MCNF) were fabricated with a vacuum filtration method, as well as positive electrodes (CP) by combining polyaniline (PANI) with carbon cloth (CC) using an in-situ polymerization method. Both positive and negative free-standing electrodes exhibited excellent electrochemical behavior and bendable/foldable flexibility. As a result, the all-pseudocapacitance asymmetric device of MCNF//CP assembled with charge-matched between anode and cathode achieves an extended voltage window of 1.5 V, high energy density of 30.6 Wh·kg−1 (1211 W·kg−1), and 86% capacitance retention after 5000 cycles, and the device maintains excellent bendability, simultaneously. This work will pave the way for the development of all-pseudocapacitive asymmetric supercapacitors (ASC) with simultaneously preeminent mechanical properties, high energy density, and wide operating voltage window.
Exploring deep residual network based features for automatic schizophrenia detection from EEG
Authors: Siuly Siuly , Guo Yanhui , Alcin Omer Faruk , Li Yan , Wen Peng , Wang Hua
Published: March 2023

Schizophrenia is a severe mental illness which can cause lifelong disability. Most recent studies on the Electroencephalogram (EEG)-based diagnosis of schizophrenia rely on bespoke/hand-crafted feature extraction techniques. Traditional manual feature extraction methods are time-consuming, imprecise, and have a limited ability to balance accuracy and efficiency. Addressing this issue, this study introduces a deep residual network (deep ResNet) based feature extraction design that can automatically extract representative features from EEG signal data for identifying schizophrenia. This proposed method consists of three stages: signal pre-processing by average filtering method, extraction of hidden patterns of EEG signals by deep ResNet, and classification of schizophrenia by softmax layer. To assess the performance of the obtained deep features, ResNet softmax classifier and also several machine learning (ML) techniques are applied on the same feature set. The experimental results for a Kaggle schizophrenia EEG dataset show that the deep features with support vector machine classifier could achieve the highest performances (99.23% accuracy) compared to the ResNet classifier. Furthermore, the proposed model performs better than the existing approaches. The findings suggest that our proposed strategy has capability to discover important biomarkers for automatic diagnosis of schizophrenia from EEG, which will aid in the development of a computer assisted diagnostic system by specialists.
Content of phenol and stilbene compounds and gene expression related to fruit development during ripening in Ampelopsis
Authors: Lee Hae In , Kim Seung Heui , Yun Hae Keun
Published: March 2023

Grapes are used worldwide and are rich in polyphenols, such as anthocyanins and stilbene compounds. Wild grapes contain abundant stilbene compounds, which are beneficial to humans. This study examined the polyphenol content and gene expression involved in skin coloration in the ripening stage of Ampelopsis spp. Accession compared to ‘VC-1’ (Vitis coignetiae) and ‘Super Hamburg’ (V. labruscana). The flavonoid content was generally higher in the Ampelopsis fruit than in the other grape lines, and the highest content among Ampelopsis accessions was found in ‘YG10075’ at 9.67 mg quercetin equivalent (QE) per g fresh weight. The anthocyanin content was highest in ‘VC-1’ at 1.2% (w/w), and the Ampelopsis accession with the highest anthocyanin content was ‘YG10062’ with 0.27%. The resveratrol content was highest in ‘VC-1’ at 70.4 μg/g, and the Ampelopsis accession with the highest resveratrol content was ‘YG10075’ with 48.5 μg/g. Expression levels of genes involved in skin color development increased during maturation in ‘VC-1’ and ‘Super Hamburg’, but decreased with maturation in Ampelopsis ‘YG10042’, ‘YG10075’, and ‘YG10062’. The expression of the genes related to stilbene compound synthesis, skin coloration, and reactive oxygen species (ROS) was high in the leaves of ‘YG10045’, young berries of ‘YG10075’, and ripe berries ‘YG-Songni4’. The gene expression showed different patterns depending on the accession of Ampelopsis, the organ, and the ripening stage. Our results indicate that ‘YG-Songni4’ is the most valuable Ampelopsis spp. accession with the highest expression of genes related to synthesis of stilbenic compounds throughout all organs. This accession could be a useful genetic resource in grape breeding programs.
Memory-Enhanced Transformer for Representation Learning on Temporal Heterogeneous Graphs
Authors: Li Longhai , Duan Lei , Wang Junchen , He Chengxin , Chen Zihao , Xie Guicai , Deng Song , Luo Zhaohang
Published: March 2023

Temporal heterogeneous graphs can model lots of complex systems in the real world, such as social networks and e-commerce applications, which are naturally time-varying and heterogeneous. As most existing graph representation learning methods cannot efficiently handle both of these characteristics, we propose a Transformer-like representation learning model, named THAN, to learn low-dimensional node embeddings preserving the topological structure features, heterogeneous semantics, and dynamic patterns of temporal heterogeneous graphs, simultaneously. Specifically, THAN first samples heterogeneous neighbors with temporal constraints and projects node features into the same vector space, then encodes time information and aggregates the neighborhood influence in different weights via type-aware self-attention. To capture long-term dependencies and evolutionary patterns, we design an optional memory module for storing and evolving dynamic node representations. Experiments on three real-world datasets demonstrate that THAN outperforms the state-of-the-arts in terms of effectiveness with respect to the temporal link prediction task.
Comparing South Africa’s Sustainability and Circular Economic Roadmap to The Rest of the World
Authors: Hoosain Mohamed Sameer , Paul Babu Sena , Doorsamy Wesley , Ramakrishna Seeram
Published: March 2023

In 2015, the United Nations Member States developed a collective blueprint for sustainability and development. The 2030 Plan includes the 17 UN-SDGs, which are an immediate call for action from all countries in the form of a global collaboration. To date, a number of countries have made significant strides in achieving the goals. One solution is the transition from a linear economy to a circular economy. Together with this, new 4IR innovative technologies has helped many countries in their transition to a circular economy as well as achieving the SDGs. Countries and organizations have also adopted environmental, social, and governance reporting as another technique, and have become mandatory in some regions and organizations. The economy of South Africa is beset by poverty and inequality, considerable unemployment, carbon-intensive, water insecurity and slow GDP growth. Furthermore, the COVID-19 epidemic has caused the economic crisis to worsen further and emphasizes the need for a new development strategy to spur economic recovery. In this paper, we will compare South Africa’s sustainability and circular economic road map to the rest of the world, and we suggest solutions and policies that can be put in place for the future benefit of the country.
The phygital transformation: a systematic review and a research agenda
Authors: Mele Cristina , Spena Tiziana Russo , Marzullo Marialuiza , Di Bernardo Irene
Published: March 2023

The label “phygital” (physical plus digital) has been proposed to describe how companies try to engage customers due to the exploitation of smart technologies. Although used mainly by practitioners, research into phygital’s theoretical development is lacking. We conduct a systematic literature review to obtain an overall vision of the phenomenon and to understand how the scientific debate uses the term. The in-depth analysis allows for the identification of four main aspects: (1) objects and applications, (2) context (space/place), (3) customer journey, and (4) shopping (retail) experience. Using the antecedents, decisions, and outcomes model, we offer an interpretation of the phenomenon in a more comprehensive framework. The development and use of physical and digital objects and applications (i.e., phygital resources) in a phygital context (i.e., spaces and places) affect the customer journey in a phygital manner to enable the development of new forms of phygital experience. We suggest specific research avenues to develop the phygital construct.
Common Elements Approaches to Implementation Research and Practice: Methods and Integration with Intervention Science
Authors: Engell Thomas , Stadnick Nicole A. , Aarons Gregory A. , Barnett Miya L.
Published: March 2023

We propose that common elements approaches can advance implementation research and practice and facilitate pragmatic use of intervention and implementation evidence. Common elements are practices or processes frequently shared by interventions or implementations. Traditional common elements methodologies use synthesis, distillation, and statistics to describe and evaluate the merit of common ingredients in effective interventions. Recent developments include identifying and testing common configurations of elements, processes, and context variables across the literature of effective interventions and implementations. While common elements thinking has grown popular in intervention science, it has rarely been utilized in implementation science, and specifically, combined with the intervention literature. The goals of this conceptual methodology paper are to (1) provide an overview of the common elements concept and how it may advance implementation research and usability for practice, (2) give a step-by-step guide to systematic common elements reviews that synthesizes and distills the intervention and implementation literature together, and (3) offer recommendations for advancing element-level evidence in implementation science. A narrative review of the common elements literature was conducted with attention to applications to implementation research. A six-step guide to using an advanced common elements methodology was provided. Examples of potential results are presented, along with a review of the implications for implementation research and practice. Finally, we reviewed methodological limitations in current common elements approaches, and identified steps towards realizing their potential. Common elements methodologies can (a) synthesize and distill the implementation science literature into practical applications, (b) generate evidence-informed hypotheses about key elements and determinants in implementation and intervention processes and mechanisms, and (c) promote evidence-informed precision tailoring of intervention and implementation to context. To realize this potential, common elements approaches need improved reporting of details from both successful and unsuccessful intervention and implementation research, more data availability, and more testing and investigation of causal processes and mechanisms of change from diverse theories.
Measuring the unmeasurable: defining and rating precarity with the aid of EU-LFS data
Authors: Symeonaki Maria , Stamatopoulou Glykeria , Parsanoglou Dimitrios
Published: March 2023

Precarity has been established as a central theoretical issue in labour market research and numerous attempts have been made in the past to provide indicators that measure it. Precarity has also been present in political discourse and linked to specific new forms of employment (temporary, part-time, insecure, and atypical amongst others) and certain social groups often defined as vulnerable groups (youth, women, ethnic minorities). However, precarity still remains a phenomenon that needs to be quantified with the use of reliable data. The present paper aims at providing a methodology for measuring individuals that are in precarious employment with data drawn from the EU-Labour Force Survey (EU-LFS). Thus, it presents a way of identifying individuals in the core of precarity and others that belong to this set to a lesser degree. More specifically, four different levels of precarity are identified and the methodology is illustrated and tested for a specific case study, that of Greece. However, the proposed technique can be applied with no or minor modifications to other data sets of EU member states, where the common EU-LFS questionnaire is used. An effort is also made to recognise the socio-demographic characteristics of the individuals that are identified as being precarious belonging to the four levels of precarity and to specify their differences. The analysis yields that as we move from the fist level of weak precarity to the last one of strong precarity the individuals become younger, worse paid and better educated.
The Uncertain World of Samson Agonistes
Authors: Shawcross John T.
Published: March 2023

Ambiguity, present in all aspects of the poem, is seen as central to Milton's authorial intentions.
European Union and the Right to Open Internet: To Boldly go where no One has Gone before
Authors: ROJSZCZAK Marcin
Published: March 2023

The discussion of the need to establish a ‘right to the internet’, ongoing now for over thirty years, has not brought about a clear resolution. Despite the growing importance of online services to both the economy and social life, there is no consensus on the limits of such a right, nor on the need to define it at all—not to mention controversy over its inclusion in the catalogue of fundamental rights.

However, the discussion about the right to internet access in the context of the EU legal system now seems obsolete. This is so, because—not through the direct modernisation of the Charter of Fundamental Rights but as part of new telecommunications legislation—a new subjective right, called the right to open internet, has emerged.

The aim of this Article is to clarify the content of this right and its relationship to the principle of network neutrality. Against this background, recent judgments of the Court of Justice will be examined and discussed. Although closely related to the telecommunications market, these judgments may serve as a starting point for further discussion on the meaning of the right to open internet in the EU legal system, including its relation to the protection of human rights.
A National Survey of Hospital Cyber Attack Emergency Operation Preparedness
Authors: Sullivan Natalie , Tully Jeffery , Dameff Christian , Opara Chibuzo , Snead Mackenzie , Selzer Jordan
Published: March 2023

Objective:

Cyberattacks on healthcare systems are increasing in frequency and severity. Hospitals need to integrate cybersecurity preparedness into their emergency operations planning and response to mitigate adverse outcomes during increasingly likely cyber events. No data currently exist regarding the level of preparedness of United States hospital systems for cybersecurity attacks. We surveyed hospital emergency managers to assess cybersecurity preparedness for these events.

Methods:

Fifty-seven emergency managers representing hospitals across the United States participated in an online Qualtrics survey regarding current preparedness and response procedures for cybersecurity hazards.

Results:

Survey responses between April 2019 and May 2021 demonstrated that a majority of hospital systems surveyed included cybersecurity disasters in their HVA (82.4%; 47/57), and most ranked it as 1 of their top 5 priorities (57.4%; 27/47). However, over half denied specifically mentioning cybersecurity in their Emergency Operations Plans (EOPs; 52.6%; 30/57). Fourteen of the 57 hospital systems (24.5%) endorsed previously activating an emergency response for a cybersecurity incident unrelated to information technology (IT) failure.

Conclusions:

The survey results suggest that American hospitals are currently underprepared for cybersecurity disasters. We emphasize the importance of prioritizing cybersecurity in Hazard Vulnerability Analyses (HVAs) and implementing specific EOP annexes for cybersecurity emergencies.
Unpacking the Black Box of China’s State Capitalism
Authors: Du Ming
Published: March 2023

Much ink has been splashed on the ideological, conceptual, and practical challenges that China’s state capitalism has posed to global trade rules. There is a growing perception that the current international trade rules are neither conceptually coherent nor practically effective in tackling China’s state capitalism. This perception has not only led to the emergence of new trade rules in regional trade agreements, but also culminated in the US-China trade war, only further aggravated by the Covid-19 pandemic. This Article contributes to the debate of what trade rules may be needed to counteract China’s state capitalism by unpacking the black box of China’s state capitalism. Based on an analysis of the nature of China’s state capitalism, this Article provides a preliminary evaluation of current trade rules taken to counteract China’s state capitalism, in particular the new rules in the Comprehensive and Progressive Agreement for Trans-Pacific Partnership, and explain why they are unlikely to be successful.
Single-frequency upconverted laser generation by phase summation
Authors: Zeng Xin , Cui Shuzhen , Jiang Huawei , Ruan Bowen , Cheng Xin , Zhou Jiaqi , Lin Zhiquan , Yang Xuezong , Chen Weibiao , Feng Yan
Published: March 2023

The phase summation effect in sum-frequency mixing process is utilized to avoid a nonlinearity obstacle in the power scaling of single-frequency visible or ultraviolet lasers. Two single-frequency fundamental lasers are spectrally broadened by phase modulation to suppress stimulated Brillouin scattering in fiber amplifier and achieve higher power. After sum-frequency mixing in a nonlinear optical crystal, the upconverted laser returns to single frequency due to phase summation, when the phase modulations on two fundamental lasers have a similar amplitude but opposite sign. The method was experimentally proved in a Raman fiber amplifier-based laser system, which generated a power-scalable sideband-free single-frequency 590 nm laser. The proposal manifests the importance of phase operation in wave-mixing processes for precision laser technology.
Shear-thickening suspensions down inclines: from Kapitza to Oobleck waves
Authors: Darbois Texier Baptiste , Lhuissier Henri , Metzger Bloen , Forterre Yoël
Published: March 2023

We investigate experimentally and theoretically the stability of a shear-thickening suspension flowing down an inclined plane. In a previous paper (Darbois Texier et al., Commun. Phys., vol. 3, 2020), we have shown that for particle volume fractions

$\phi$

above the discontinuous shear-thickening fraction

$\phi _{DST}$

, long surface waves grow spontaneously at a flow Reynolds number much below 1. This motivated a simplified analysis based on a purely inertialess mechanism, called the ‘Oobleck waves’ mechanism, which couples the negatively sloped rheology of the suspension with the free-surface deflection and captures well the experimental instability threshold and the wave speed, for

$\phi >\phi _{DST}$

. However, neglecting inertia does not allow us to describe the inertial Kapitza regime observed for

$\phi <\phi _{DST}$

, nor does it allow us to discriminate between Oobleck waves and other inertial instabilities expected above

$\phi _{DST}$

. This paper fills this gap by extending our previous analysis, based on a depth-averaged approach and the Wyart–Cates constitutive shear-thickening rheology, to account for inertia. The extended analysis recovers quantitatively the experimental instability threshold in the Kapitza regime, below

$\phi _{DST}$

, and in the Oobleck waves regime, above

$\phi _{DST}$

. By providing additional measurements of the wave growth rate and investigating theoretically the effect of a strain delay in the rheology, it also confirms that the instability observed above

$\phi _{DST}$

stems from the non-inertial Oobleck wave mechanism, which is specific to free-surface flows and dominates modes of inertial origin. These results emphasize the variety of instability mechanisms for shear-thickening suspensions and might be relevant to free-surface flows of other complex fluids displaying velocity-weakening rheology.
A note on the differentiability of discrete Palmer's linearization
Authors: Castañeda Álvaro , Jara Néstor
Published: March 2023

In the context of discrete nonautonomous dynamics, we prove that the homeomorphisms in the linearization theorem are $C^2$ diffeomorphisms. In contrast to other related works, our result does not involve non-resonance conditions or spectral gaps. Our approach is based on the interlacing of the properties of nonautonomous hyperbolicity of the linear part, and boundedness and Lipschitzness of the nonlinearities. Moreover, we propose a functional approach to find conditions for regularity of arbitrary degree.
Design of control laws to implement ACT benefits
Authors: Jones J. G.
Published: March 2023

The emergence of active control technology (ACT) as a design feature of future combat aircraft raises three fundamental requirements (a) the identification of those areas where active control is likely to make for more efficient designs (b) the development of a capability to produce system hardware and software satisfying the stringent integrity requirements which the envisaged ACT applications demand, and (c) the development of a capability to implement successfully the ACT benefits, emerging from (a), by means of appropriate control laws.

This paper is concerned primarily with Item (c). Subjects considered include the design of control laws for fast target acquisition and precise tracking, the design of ride-smoothing systems, control laws for manoeuvre limiting at high angles of attack, and flying qualities problems associated with aerodynamically-unstable air-craft.

The design of control laws takes place through a series of steps including initial computer-aided studies followed by ground-based simulation with the pilbt-in-the-loop and ultimate validation (probably with re-tuning of control-loop parameters) through flight test.
New technology in commercial aircraft design for minimum operating cost
Authors: Stewart D. J. , Campion B. S.
Published: March 2023

Traffic growth and the replacement of the older, less efficient and noisier aircraft—60% of Western World capacity may be regarded as in this category—provide the opportunity for applying new technologies to subsonic commercial transports. Reduction of operating cost continues to provide the major incentive, though increasing emphasis is being placed on low fuel consumption and low noise.

In this paper, the term ‘advanced technology’ is taken to embrace significant engineering advances which are not commonplace on aircraft flying today. In general, it is wrong to think of such advances as new inventions. Almost without exception they have evolved over the years, with few quantum jumps. There are, of course, exceptions to this and a recent example as regards engine development might be the introduction of high bypass ratio engines in the late 1960s, which brought about a 25% improvement in specific fuel consumption. However, even this major step could be regarded as an evolutionary development from engines of bypass ratio about 1·0, which themselves had conferred significant gains relative to the straight turbo-jet engines of the late 1950s.
The efficiency of aerial spraying
Authors: Spillman J. J.
Published: March 2023

Nobody would deny that a major objective of the peoples of the world is to improve standards of health and hygiene and an essential part of this must be to increase the quantity of food produced. To do this it is essential to use supplementary nutrients and exercise effective pest management. It has been shown that the yields of basic foods, such as rice, can be doubled by using the right seed strains, fertilisers and crop protection techniques. Crop yield losses because of insects alone are estimated at 5% in Europe where insecticides are used widely and as much as 21% in Asia where insecticides are used only in a few of the better organised cultural areas.
The use of the power spectral density function to measure the effects of motion on an aircraft simulation
Authors: Ekin W. H. , McCloy D.
Published: March 2023

Although hundreds of moving base simulators exist in the world today, there is a paucity of objective and quantitative methods of assessing the necessity for, and the effectiveness of the motion provided. This paper describes a quantitative method of assessing the effects of motion on an aircraft simulation when there is short-term interactive control of the aircraft by the pilot.
Finite elements for honeycomb sandwich plates and shells
Authors: Holt P. J. , Webber J. P. H.
Published: March 2023

The honeycomb sandwich type of construction in plate and shell shapes is playing an increasing role in aerospace structures where structural efficiency is important. In some applications, such as wing or control surface trailing edges, the core is of non-constant thickness, and in others, such as engine thrust reverser buckets, the shell shape is doubly curved. Faceplates are commonly manufactured from aluminium, stainless steel or other metals, but the use of anisotropic materials, such as carbon fibre reinforced plastics (CFRP) can be expected to increase in the future.

In finite element analysis, as in analytical work, sandwich plates and shells have received far less attention than thin plates and shells. However, elements have been developed specifically for sandwich plates by Barnard, Cook and Bartelds and Ottens. Of these, only the latter allows a non-constant core thickness. Evidently, such elements could be used in a facet shell representation. Only two general (as opposed to axisymmetric) curved elements specifically formulated to deal with sandwich shells seem to have appeared in the literature. Both are subject to deficiencies as noted for thin shells by Morris, and Webber discusses certain geometrical errors in the doubly curved element of Reference 5. Furthermore, both are of limited practical application. It may be concluded, therefore, that there is a need for a honeycomb sandwich shell element which is easy to use and accurate while being capable of modelling the full range of materials and shapes found in practical structures. To this end, a family of elements for use in the linear elastic finite element method is formulated. They are of general doubly curved shape and can be used to approximate thick and thin shells of positive, zero and negative Gaussian curvature in a simple and straightforward manner. They also include anisotropic faces and non-constant core thickness. Degrees of freedom are limited to three displacements at each node, and this allows mixing with other element types.
The role of aircraft in the management of insect populations in crops in the year 2000
Authors: Schaefer G. W.
Published: March 2023

Although 2000 AD is but 20 years away, even so this is a long period in terms of the rate of recent technological development. My remarks about the possible future state of this subject must therefore be somewhat speculative. The projections will be based, however, on research carried out over the past 10 years, and I hope this will provide an element of usefulness.

I shall refer to both agricultural and forestry crops. Our most extensive agricultural experience has been with cotton and its pests in the Sudan, particularly the cotton bollworm moth; and with cereals in the UK, particularly cereal aphids. Our forestry experience has been with softwoods and the spruce budworm moth in eastern Canada, and with lodge-pole pine forests and the pine beauty moth in Scotland. In terms of techniques our experience has ranged over ground-based and airborne radars, a full range of ground and airborne meteorological instrumentation, the study of insect flight behaviour by sensitive infra-red opto-electronic devices, the turbulent dispersal of spray droplets and their deposition on foliage and insects, the study and quantification of insect population dynamics, and the use of many biological techniques, including suction traps and light traps.
Aerial photography as an aid to pest forecasting
Authors: Hooper A. J.
Published: March 2023

Control of agricultural pests and diseases has been attempted for well over one thousand years, but it is only during the present century that the means have been available to combat the problems on a large scale by the use of pesticides. The contribution which pesticides have made to the reduction of crop losses is enormous. However, the fact that significant losses of production still occur shows that they are not a complete or simple answer to the problems.

When used in the broadest sense the term ‘pest' applies to a wide range of plant and animal organisms which adversely affect the crops grown by man. Attention here will be restricted to invertebrate pests and crop diseases.
Developments in aircraft power flying control hydraulics
Authors: Honey N.J.
Published: March 2023

As we are all aware, an aircraft in flight has six degrees of freedom. Three translational, that is, lateral, longitudinal and vertical and three rotational that is, rotation about the roll pitch and yaw axes. It is the actuation and control of the surfaces which cause rotation that will be discussed.

For the vast majority of aircraft, control in the three axes of rotation is achieved by three distinct movable surfaces which are elevators for pitch control, ailerons for roll control and rudder for yaw control. The effects of these controls are as follows—Fig. 1 the elevators will alter the angle of attack of the aircraft to the air and unless power is increased will result in a reduction in airspeed. If the airspeed is allowed to drop too much there will be a loss of lift on the wing and eventually a stall will occur. The ailerons will cause the aircraft to roll and alter the angle of bank. In so doing however the aircraft will begin to side slip, thus as there is more surface area aft of the cg than before it, the aircraft will turn.
The development of the composite material engine nacelle
Authors: Bennett H. W.
Published: March 2023

Design studies have shown that the successful application of carbon fibre composites to suitable components in the RB 211 engine nacelle could achieve initially a weight saving of 200 to 250 kg per power plant.

In the future the employment of the long mixed flow nacelle, and possibly higher by-pass ratio cycles, aimed at optimising engine design for maximum fuel and operating economy, will emphasise even further the need for lightweight nacelle structures.
Flight simulation at Cranfield Institute of Technology
Authors: Golding R. J.
Published: March 2023

Is flight simulation of academic interest? As we have a fairly substantial involvement at Cranfield, the answer must be ‘Yes'—although the amount of student involvement is small and our main activity is in contract work. This is explained later in the paper.

Most of the flight simulation work takes place in the Aeronautical Instrumentation and Data Processing Laboratories of the College of Aeronautics. Some takes place in the School of Electronic Systems Design.
The role of simulation in automatic flight control systems research
Authors: Prasad R. A. , Saoullis S. L. A. , Tsitsilonis L.
Published: March 2023

Of all the branches of engineering, we regard aeronautical engineering as that which most needs simulation as an essential element of its constitution. Not even by choice may an aeronautical engineer be unfamiliar with simulation, for its advantages in the phases of design, production, and operation of aircraft are recognised by every aeronautical organisation, and its effectiveness, either in producing acceptable answers to flight problems, or in demonstrating flight characteristics, is the authority by which academics can insist upon the inclusion of the elements of simulation in their syllabuses. It is our belief that simulation has come to occupy this central position mainly as a result of the fundamental problems of safe flight.
An objective method of assessing the realism of a simulation of a simple control system
Authors: Ekin W. H. , McCloy D.
Published: March 2023

Although the latest aircraft flight simulators incorporate much recent technical development and are becoming increasingly accepted by the world's airlines, government regulatory agencies and air forces for pilot training and checking, there does not exist any completely satisfactory objective method for assessing their realism. If an objective method of measuring the realism of an aircraft simulator could be developed, it might be possible to reduce the often lengthy period needed by the simulator manufacturer in making final adjustments (tweaking) before customer acceptance, or to monitor the realism in service (15 year service life being typical), or to achieve the same degree of realism with equipment of a significantly lower specification and therefore much lower cost.
Swedenborg's flying saucer
Authors: Hart Clive
Published: March 2023

As early as 1714, when he was 26, Emanuel Swedenborg (1688-1772) showed an interest in the possibility of building a flying machine. Writing from Rostock on 8th September 1714 to his brother-in-law Erik Benzelius, he ambitiously listed 14 inventions which he had under way and about which he had prepared manuscript notes. The projected inventions included ‘a kind of flying chariot, or the possibility of being sustained in the air and of being carried through it’. Two years later, in 1716, Swedenborg founded Sweden's first scientific journal, Daedalus Hyperboreus, in the fourth number of which he anonymously published a short article entitled ‘Utkast til en Machine at flyga i wädret’ (Sketch of a Machine for Flying in the Air).
Views of air carriers British Airways
Authors: Stuart Charles
Published: March 2023

This last year has shown how delicate a balance exists between all constituent parts of our travel industry. Airlines, airports, air navigation, governments, travel trade, hoteliers, tourism institutions, aircraft manufacturers and above all, consumers have faced uncertainty and change. Most changes have been sudden, some have been successful, and others have proved difficult.

Main beneficiaries of recent relaxations in price and entry rules have, so far, been some scheduled airlines (through increased revenue) and some passengers (through lower fares). Airports, charter airlines, people living near airports, tourism institutions, even governments, have all shown less enthusiasm (especially at peak times).
British Caledonian Airways
Authors: Thomson Adam
Published: March 2023

It is said that 1978 was a great year for the consumer: IATA's face was pushed in the mud; President Carter had a great new freedom of the skies policy; and the CAB had a new deregulation policy. At long last the consumer benefited from the massive new spread of low fares.

This is a gross exaggeration; low fares have been around for a long, long time. European inclusive tours, for instance, through the fifties, sixties and seventies, through trials and disasters, have grown to be a new way of life for the holidaymaker and vacationer from Northern Europe, who vacates Northern Europe en masse in the spring, in the summer, through the autumn and goes to the Mediterranean. No other way could that have been done without the promotion of low fares as part of a total package.
Aeroport de Paris
Authors: Ailleret F.
Published: March 2023

To begin I should like to point out that Aeroport de Paris is a public establishment, somewhat similar in structure to the British Airports Authority, whose role is to conceive, study, build and operate civil airports in the Paris region. Our two major commercial airports are Orly and Roissy-Charles de Gaulle. In 1978 their cumulated traffic amounted to 23·5 million passengers, 500 000 metric tons of freight and 290 000 aircraft movements.

The recent history of world air transport is marked with profound upheavals: the advent of jet aircraft, then of jumbo jets, the growth of charter airlines, the creation of airlines by countries having obtained their independence, oil crises, … the latest of these events laden with consequences is without doubt the fundamental questioning of the tariff system as demonstrated by IATA's breakdown, the American deregulation and the re-negotiation of bilateral agreements.
Effects on tourism British Tourist Authority
Authors: Lickorish L. J.
Published: March 2023

'Low-Fares’ is a misleading term. Low compared with what? It certainly implies change. Perhaps ‘lower’ fares are what the debate is all about. There are tourism as well as aviation conditions.

Fares are vital to tourism. A quarter of a century of low fares has supported the world tourism boom, making tourism the biggest single factor in world trade, and produced a growth rate of 8-9%, considerably higher than that for world trade as a whole. In particular, the trans-Atlantic fare revolution is not new.

The journal of the ITA gave an illustration of this, comparing a package tour New York/Rome for Holy Year 1950 priced at $585 and the same offer for the second Holy Year 1975 at $580. Taking into account the equivalent dollar purchasing power, the 1950 offer represented a price of $1400. ‘Eternal bliss', said the ITA reporter, ‘at half the price!’
Aerospatiale AS.350 and AS.355
Authors: Boulet J.
Published: March 2023

The five-six seater single-engine helicopters represent a large share of the civil market. The market studies show that the main target to be reached in this field is to succeed in having a purchase price and operating costs significantly lower than those of current aircraft.

But the quality aspect of the helicopter should not be overlooked: the comfort and performance data should remain at a competitive level; the helicopter should have a high reliability level and offer easy maintenance characteristics.

Therefore the light advanced helicopter should represent an excellent cost efficiency compromise. This was the constant target kept in mind all along the design, development and production phases of the AS.350 (see Fig. 1).
Short haul transport for the 1990s
Authors: Robinson P. , Brown D.G.
Published: March 2023

One big problem found during the course of preparing this lecture, was the vastness of the subject. So there will probably be many things that should be said that will be left unsaid, but it is hoped that all the main factors have been considered at some point, even if they only get a passing mention. One point should be made, the freight and cargo market are not considered, as the majority of freight is carried in converted passenger aircraft or in the holds of passenger aircraft particularly in the large wide-body types. This trend seems likely to continue and it is unlikely that specialised freight aircraft will be developed for short haul operations.
Supersonic combat aircraft design
Authors: Fletcher J. , Burns B. R. A.
Published: March 2023

It should be fairly obvious that, in contemplating the design of a future combat aircraft, it is important at the outset to relate the effort to some forecast definition of what is needed. This may take the form of an official or an unofficial requirement; however, its precise form is immaterial to the central argument. Either way, it is necessary to recognise several limitations to a so-called requirement:

i)

the chances of it being ‘right’, some 10-20 years before the realisation of its potential wartime application, is fairly remote. This is particularly true with today’s rapid advancement in, for example, weapons and sensor technology. These developments make it doubly difficult to predict the nature and strength of the threat force;

ii)

the postulated scenarios will change from day to day, and indeed, during the day–according to the course of the main battle; therefore the military commander's requirements of the forces at his disposal can change by the hour;

iii)

the environment, both militarily and climatically, plays a large part in the definition of a design. The variability of the environment is neglected only with grave risk to the eventual utility of the weapon system.
Combat aircraft development–looking backward to look forward 1935–1990
Authors: Boot R. D.
Published: March 2023

It is traditional in looking to the future to analyse past experience. In this paper the processes of development of 25 UK combat (or fighter-bomber) types covering a period of 45 years have been analysed and compared with available data on 20 US types.

In this analysis:

(i)

Date of the project has been taken as date of Instruction to Proceed rather than the more usual first flight or entry into service dates, as it is felt that this more accurately represents technological projections involved.

(ii)

Of necessity aircraft empty weight has been used as a basic parameter. While AMPR weight is more conventional in modern estimating, it is impossible to obtain such data for older types, but in a broad review such as this empty weight would seem to be an acceptable parameter.

(iii)

Costs have been corrected to 1978 monetary values using curves deduced from cost of living and aerospace product data for both UK and USA.
Continuing structural airworthiness of civil transport aircraft
Authors: Richards P. F.
Published: March 2023

The keynote address given by Mr. Chouffot to this convention summarises the reasons for the growing concern of the airworthiness authorities and industry alike for the structural integrity of ageing civil transport aircraft and the measures taken to ensure their continued safety.

This paper explains in greater depth the background for these concerns and the actions taken.

I would like first to briefly review the airworthiness philosophy underlying the structural development of presentday aircraft.
Airworthiness of long-life jet transport structures
Authors: Goranson U. G. , Hall John
Published: March 2023

Boeing has recently completed a structural integrity reassessment of 707 aircraft models, and released a Supplemental Inspection Document (SID). Similar activities are now progressing for model 727. Structural reassessments are continuous over the operational life of all Boeing aircraft models and used for developing inspection information directed toward detecting structural damage before it becomes a serious problem in the fleet.

The fail-safe design concept requires interaction between the designer /manufacturer and the airline operators. Within this concept, maintenance and inspection are equally important as the basic design. It is important for operators to provide continuous vigilance of aircraft structure to detect damage and perform timely maintenance. Knowledge of damage that is occurring in the fleet is essential to the manufacturer to provide timely advice through service bulletins or other publications. This interchange is depicted in Fig. 1, and is the foundation of the fail-safe design concept.
MRCA Tornado: Achievement by international collaboration
Authors: Heath B. O.
Published: March 2023

In this lecture I wish to cover:

1.

What the Tornado is.

2.

What the starting conditions for it were.

3.

Overall formal management aspects.

4.

Detailed and pragmatic aspects of management.

5.

Achievement.

6.

General remarks.

It is usual to say that views expressed are personal and do not necessarily represent those of the Companies concerned. This seems somewhat ironic to me, involved in international collaboration, where most statements of any definition do have international agreement, but reference in depth to my many colleagues on such a wide aspect has not been possible.
Advances in aeroacoustic wind tunnel testing techniques for aircraft noise research
Authors: Williams J. , Holbeche T. A.
Published: March 2023

To ensure meaningful evaluation and prediction of configuration and flight effects on aircraft noise generation and propagation, reliable representation and measurement of relevant aerodynamic flow conditions as well as of acoustic characteristics must be possible. Acoustic wind tunnels, with models mounted in a quiet test section airstream surrounded by an anechoic working chamber, have now been established as primary tools for noise-model research work and should next be exploited also for the direct support of specific quiet aircraft projects. The special advantages of such tunnels in ensuring a more sheltered and controlled environment than outdoor mobile-model facilities and flight testing include capability of continuous operation, repeatable test conditions, high productivity, good measurement accuracy, testing flexibility, and the precise alleviation of reflections from neighbouring surfaces. Of course the recent experience on noise testing under forward speed conditions and on associated techniques is still very limited at both model scale and full scale, as compared with extensive and continuous aerodynamic testing over half a century. However, many of the problem areas associated with subsonic tunnel design and application for noise-model testing, as identified over five years ago, have now been clarified. Also, the special treatments or limitations involved have become quantifiable in many respects, as discussed later under the convenient main headings of tunnel test section requirements (section 2), tunnel circuit design (section 3), special measurement and analysis techniques (section 4) and model scale simulation (section 5).