18,043 results match your criteria Aircraft Engineering And Aerospace Technology[Journal]


Experiments and Finite Element Simulations of Composite Laminates Following Low Velocity On-Edge Impact Damage.

Polymers (Basel) 2022 Apr 25;14(9). Epub 2022 Apr 25.

Laboratory of Aircraft Structure and Strength, Shanghai Jiao Tong University, Shanghai 20024, China.

Composites are widely used in aircraft structures that have free edges and are vulnerable to impact events during manufacturing and maintenance. On-edge impact may have a great contribution in terms of the compression strength loss of composites, but the influence remains unclear. This paper presents experiments and simulations of carbon-fiber-reinforced plastic (CFRP) materials with on-edge impact and compression after edge impact (CAEI). Read More

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Improving Electromagnetic Interference Shielding While Retaining Mechanical Properties of Carbon Fiber-Based Composites by Introducing Carbon Nanofiber Sheet into Laminate Structure.

Polymers (Basel) 2022 Apr 20;14(9). Epub 2022 Apr 20.

Shanghai Collaborative Innovation Center of High Performance Fibers and Composite (Province-Ministry Joint), Center for Civil Aviation Composites, Donghua University, Shanghai 201620, China.

The demands for carbon fiber reinforced composites (CFRCs) are growing in the aviation industry for fuel consumption savings, despite the increasing risk of electromagnetic interference (EMI). In this work, polyacrylonitrile (PAN) sheets were prepared by electrospinning. Carbon nanofiber (CNF) sheets were obtained by the carbonization of PAN sheets. Read More

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The Prevalence of Dietary Supplement Usage in Military Aviators.

Int J Environ Res Public Health 2022 Apr 20;19(9). Epub 2022 Apr 20.

German Air Force Centre of Aerospace Medicine, Section Experimental Aerospace Medicine Research, Flughafenstrasse 1, 51147 Cologne, Germany.

Background: The prevalence of dietary supplement (DS) and energy drink (ED) usage in military personnel differs from branch to branch and is between 55% and 76% (higher values in special operations forces). Aviators with highly demanding tasks might be especially interested in using dietary supplements. To date, there are only limited data available for this special profession inside the military. Read More

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Integrated Multiomics Analysis of Salivary Exosomes to Identify Biomarkers Associated with Changes in Mood States and Fatigue.

Int J Mol Sci 2022 May 9;23(9). Epub 2022 May 9.

The Drug Discovery Lab, Department of Neurology, David Geffen School of Medicine, 710 Westwood Plaza, University of California Los Angeles, Los Angeles, CA 90095, USA.

Fatigue and other deleterious mood alterations resulting from prolonged efforts such as a long work shift can lead to a decrease in vigilance and cognitive performance, increasing the likelihood of errors during the execution of attention-demanding activities such as piloting an aircraft or performing medical procedures. Thus, a method to rapidly and objectively assess the risk for such cognitive fatigue would be of value. The objective of the study was the identification in saliva-borne exosomes of molecular signals associated with changes in mood and fatigue that may increase the risk of reduced cognitive performance. Read More

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The Lighter Side of Aviation Medicine during World War 2: Aero Medical Training Cartoons.

Authors:
Jay B Dean

FASEB J 2022 May;36 Suppl 1

Molecular Pharmacology & Physiology, University of South Florida at Tampa, Tampa, FL.

The air war of 1939-1945 was the world's first high-speed, high-altitude air war. The limiting factor in aerial combat was no longer the warplane's performance, but rather, the aviator's limited tolerances for exposure to the rarefied, anoxic, subzero atmosphere. Aviators flew unpressurized planes to altitudes of 20,000-35,000 feet during reconnaissance and bombing missions to evade enemy interceptors and anti-aircraft fire. Read More

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Fault Estimation Observer Design for Markovian Jump Systems With Nondifferentiable Actuator and Sensor Failures.

IEEE Trans Cybern 2022 May 13;PP. Epub 2022 May 13.

This article addresses the simultaneous actuator and sensor fault estimation (FE) problem for a class of Markovian jump systems (MJSs) with nondifferentiable actuator failures. In order to overcome the difficulties brought by the nondifferentiable actuator failures, we construct an extended vector composed of states, sensor faults, and disturbances, where the derivatives of actuator failures are not required in this augmented system. Then, two novel observer-based approaches are developed for the augmented descriptor system to cope with the FE problem. Read More

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Moderate hypoxia decreases selective attention performance as assessed via a domain-specific gamified assessment.

FASEB J 2022 May;36 Suppl 1

Kinesiology, Indiana University, Bloomington, IN.

Introduction: The effect of acute hypoxia on cognition is a function of the magnitude and duration of hypoxia and the assessed cognitive domain. For example, there is little effect of acute exposure to a fraction of inspired oxygen (F O ) of 11-14% on simple cognitive tasks. However, performance on more complex tasks, such as those involving aspects of executive function, can be hindered under the same conditions. Read More

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A gamified assessment does not identify alterations in cross-domain cognitive performance with acute moderate hypoxia.

FASEB J 2022 May;36 Suppl 1

Kinesiology, Indiana University, Bloomington, IN.

Introduction: The acute effect of hypoxia on cognition is dependent on the magnitude and duration of the hypoxia, and the assessed cognitive domain. For example, there is little effect of ~1 h exposure to a fraction of inspired oxygen (F O ) of ~14% on simple cognitive tasks that measure reaction time. However, complex or novel cognitive tasks can be hindered under the same conditions. Read More

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Fixed-Wing Motorized Aircraft Accidents: Analysis of Injury Severity and Concomitant Factors (2000-2019).

Aerosp Med Hum Perform 2022 May;93(5):442-449

There is a paucity of research on general aviation accidents in Germany. The authorities investigate only a fraction of all national accidents. The current study analyzes existing accident reports and aims to identify injury severity in regard to concomitant risk factors. Read More

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Assessing work role strain, burnout, and job satisfaction among remotely piloted aircraft operators: the moderating role of unit social support.

Psychol Health Med 2022 May 13:1-14. Epub 2022 May 13.

Aerospace Medicine Department, U.S. Air Force School of Aerospace Medicine, Wright-Patterson Air Force Base, Ohio, USA.

Utilizing the Job Demands-Resources (JD-R) theory as a guiding framework, the current study examined the relationships between job demands (work role strain) and occupational outcomes (burnout and job satisfaction) and assessed how job resources (team member social support and leader social support) mitigated the impact of high job demands for U.S. Air Force remotely piloted aircraft (RPA) operators. Read More

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Crystal structure and Hirshfeld surface analysis of ()-1-[2,2-di-bromo-1-(4-nitro-phen-yl)ethen-yl]-2-(4-fluoro-phen-yl)diazene.

Acta Crystallogr E Crystallogr Commun 2022 May 28;78(Pt 5):530-535. Epub 2022 Apr 28.

Department of Chemistry, M.M.A.M.C (Tribhuvan University) Biratnagar, Nepal.

In the title compound, CHBrFNO, the 4-fluoro-phenyl ring and the nitro-substituted phenyl ring form a dihedral angle of 64.37 (10)°. Mol-ecules in the crystal are connected by C-H⋯O and C-H⋯F hydrogen bonds into layers parallel to (011). Read More

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3D Biomechanical Modeling for Sitting Contact Stress Analysis.

J Biomech Eng 2022 May 12. Epub 2022 May 12.

Department of Aerospace Engineering, Ryerson University, Toronto, Canada, 350 Victoria Street, Toronto, ON, CA, M5B 2K3.

This paper proposes a 3D biomechanical model of the upper body and analyzes the interaction between the upper body and aircraft seat backrest for different sitting postures and backrest recline angles. The reclined sitting postures of the upper body are defined based on the available spine biomechanical data and the multibody inverse kinematics method. The contact loadings on each contacted spine segment are calculated based on the Newton-Euler dynamic formulation. Read More

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A bioinspired revolving-wing drone with passive attitude stability and efficient hovering flight.

Sci Robot 2022 May 11;7(66):eabg5913. Epub 2022 May 11.

Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Hong Kong SAR, China.

Among small rotorcraft, the use of multiple compact rotors in a mechanically simple design leads to impressive agility and maneuverability but inevitably results in high energetic demand and acutely restricted endurance. Small spinning propellers used in these vehicles contrast with large lifting surfaces of winged seeds, which spontaneously gyrate into stable autorotation upon falling. The pronounced aerodynamic surfaces and delayed stalls are believed key to efficient unpowered flight. Read More

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Assessment of in-cabin noise of wide-body aircrafts.

Appl Acoust 2022 Jun 6;194:108809. Epub 2022 May 6.

Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore.

The aviation industry has seen dramatic growth over the decades till the recent disruption due to the COVID-19 pandemic. Moreover, long-haul routes with a distance of more than 4000 km are common for major airlines worldwide. Therefore, aircraft cabin noise assessment is essential, especially in long-haul flights, for passenger and flight crew health wellness. Read More

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Helicopter inter-hospital transfer for patients undergoing extracorporeal membrane oxygenation: a retrospective 12-year analysis of a service system.

Scand J Trauma Resusc Emerg Med 2022 May 7;30(1):33. Epub 2022 May 7.

Department of Anaesthesiology and Intensive Care Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.

Background: Patients undergoing extracorporeal membrane oxygenation (ECMO) are critically ill and show high mortality. Inter-hospital transfer of these patients has to be safe, with high survival rates during transport without potentially serious and life-threatening adverse events. The Swiss Air-Rescue provides 24-h/7-days per week inter-hospital helicopter transfers that include on-site ECMO cannulation if needed. Read More

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Torsional vibration analysis of shaft with multi inertias.

Authors:
Tao Peng Qun Yan

Sci Rep 2022 May 5;12(1):7333. Epub 2022 May 5.

Aviation Science and Technology Key Laboratory of Aviation Acoustics and Vibration, Joint Laboratory of Turboprop Aircraft Vibration and Noise Reduction Technology, Aircraft Strength Research Institute of China, No. 86, Electronic 2nd Road, Yanta District, Xi'an, 710065, Shaanxi, China.

An analytical method is proposed to investigate the torsional vibration of the uniform circular shaft with multiple concentrated inertias. The governing equation is established based on the Hamiltonian principle and verified by the dynamical method. The theoretical solutions of frequencies and mode shapes under different boundary conditions are obtained using the separation variable method and integral transformation. Read More

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Vibration Control of a Helicopter Rescue Simulator on a Flexible Base.

Comput Intell Neurosci 2022 25;2022:7173421. Epub 2022 Apr 25.

Naval Architecture and Ocean Engineering College, Dalian Maritime University, DaLian 116026, Liaoning, China.

The vibration compensation control of a hovering helicopter rescue simulator mounted on a crane beam is studied in this research. A Stewart platform is used as the motion generator of the helicopter simulation cabin and the vibration compensation device of the beam, simultaneously. This study describes how the dynamic model of the Stewart platform with consideration of the beam vibration is established. Read More

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UAS-based real-time water quality monitoring, sampling, and visualization platform (UASWQP).

Authors:
Jae Hyeon Ryu

HardwareX 2022 Apr 11;11:e00277. Epub 2022 Feb 11.

University of Idaho, United States.

Urbanization, land use change, and agricultural activities continue to affect water quality standards at the urban-rural interface, such as the Boise River System located in Idaho, USA. This project demonstrates how the off-the-shelf unmanned aircraft system (UAS, also known as drone) equipped with other necessary hardware attachments can be used to monitor real-time water quality components, including pH, water temperature, electric conductivity (EC), and dissolved oxygen at open waterbodies. The proposed UAS-based hardware platform for water quality studies (UASWQP) appears a promising tool to advance environmental research activities, especially for impaired waterways (e. Read More

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Neural-Fly enables rapid learning for agile flight in strong winds.

Sci Robot 2022 May 4;7(66):eabm6597. Epub 2022 May 4.

Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, USA.

Executing safe and precise flight maneuvers in dynamic high-speed winds is important for the ongoing commoditization of uninhabited aerial vehicles (UAVs). However, because the relationship between various wind conditions and its effect on aircraft maneuverability is not well understood, it is challenging to design effective robot controllers using traditional control design methods. We present Neural-Fly, a learning-based approach that allows rapid online adaptation by incorporating pretrained representations through deep learning. Read More

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Impact of aeroplane noise on mental and physical health: a quasi-experimental analysis.

BMJ Open 2022 May 2;12(5):e057209. Epub 2022 May 2.

Health Policy and Management, Columbia University Mailman School of Public Health, New York, New York, USA.

Objectives: Historically, departures at New York City's LaGuardia airport flew over a large sports complex within a park. During the US Open tennis games, flights were diverted to fly over a heavily populated foreign-born neighbourhood for roughly 2 weeks out of the year so that the tennis match was not disturbed (the 'TNNIS' departure). In 2012, the use of the TNNIS departure became year-round to better optimise flight patterns around the metropolitan area. Read More

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[Flying and COVID-19: options to reduce the risk of transmission].

Ned Tijdschr Geneeskd 2022 02 16;166. Epub 2022 Feb 16.

Contact: Gerard Hageman

With air travel continuing after the SARS-CoV-2 pandemic as before, is there a risk of in-flight-transmission? We found 18 papers describing a total number of 306 index patients on 150 flights, 79 infected passengers and four infected cabin crew. Infection transmission within the aircraft cabin depends on flight occupancy, proximity to the index patient, duration of flight and the prevailing virus variant. A negative PCR-test has a sensitivity of 95 %, around 5 % of travelers will get a false negative result. Read More

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February 2022

TransEffiDet: Aircraft Detection and Classification in Aerial Images Based on EfficientDet and Transformer.

Comput Intell Neurosci 2022 21;2022:2262549. Epub 2022 Apr 21.

College of Systems Engineering, National University of Defense Technology, Changsha 410082, China.

In recent years, analysis and optimization algorithm based on image data is a research hotspot. Aircraft detection based on aerial images can provide data support for accurately attacking military targets. Although many efforts have been devoted, it is still challenging due to the poor environment, the vastness of the sky background, and so on. Read More

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Spatio-Temporal Coding-Based Helicopter Trajectory Planning for Pulsed Neural Membrane System.

Comput Intell Neurosci 2022 17;2022:1787013. Epub 2022 Mar 17.

Department of Information Engineering, PLA Army Academy of Artillery and Air Defense, Hefei City, Anhui Province 230031, China.

For the trajectory planning problem under the nonlinear and strongly coupled characteristics of unmanned helicopters, membrane computing with distributed parallel processing capability is introduced for unmanned helicopter trajectory planning. The global and local spatial information is temporally characterized; the temporal characterization algorithm under mapping information is designed; the hierarchical discriminant regression algorithm is designed based on incremental principal component analysis to realize the process of building and identifying trees in trajectory planning; and the pulsed neural membrane system (PNMS) with spatio-temporal coding function under membrane computing is constructed. Compared with the RRT algorithm in two experimental environments, the original path length, the trimmed path length, the time used to plan the trajectory, and the number of search nodes have different levels of improvement; the feasibility and effectiveness of the PNMS in unmanned helicopter trajectory planning are verified. Read More

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Visual Landing Based on the Human Depth Perception in Limited Visibility and Failure of Avionic Systems.

Comput Intell Neurosci 2022 22;2022:4320101. Epub 2022 Apr 22.

Department of Aerospace Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.

This paper introduces a novel visual landing system applicable to the accurate landing of commercial aircraft utilizing human depth perception algorithms, named a 3D Model Landing System (3DMLS). The 3DMLS uses a simulation environment for visual landing in the failure of navigation aids/avionics, adverse weather conditions, and limited visibility. To simulate the approach path and surrounding area, the 3DMLS implements both the inertial measurement unit (IMU) and the digital elevation model (DEM). Read More

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A PVA/LiCl/PEO interpenetrating composite electrolyte with a three-dimensional dual-network for all-solid-state flexible aluminum-air batteries.

RSC Adv 2021 Dec 13;11(62):39476-39483. Epub 2021 Dec 13.

Earth Engineering Center, Center for Advanced Materials for Energy and Environment, Department of Earth and Environmental Engineering, Columbia University New York NY 10027 USA

Aluminum-air batteries are promising electronic power sources because of their low cost and high energy density. However, traditional aluminum-air batteries are greatly restricted from being used in the field of flexible electronics due to the rigid battery structure, and the irreversible corrosion of the anode by the alkaline electrolyte, which greatly reduces the battery life. To address these issues, a three-dimensional dual-network interpenetrating structure PVA/LiCl/PEO composite gel polymer electrolyte (GPE) is proposed. Read More

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December 2021

Droplet deposition and pest control efficacy on pine trees from aerial application.

Pest Manag Sci 2022 May 1. Epub 2022 May 1.

College of Electronic Engineering, South China Agricultural University, Guangzhou, 510642, China.

Background: Aerial application, a spraying method with aircraft as the application platform, is one of the most important contents of pest control in pine forests. This work aimed to investigate the movement and distribution patterns of droplets and the pest control effectiveness of helicopter spraying on Masson pine (MP) and Korean pine (KP) trees. In particular, three nozzle types (CP02, CP03 and CP04) were evaluated and compared at the same spray volume rate (15 L·ha ) in both wind tunnel and field trials. Read More

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Assessment of the mental workload of trainee pilots of remotely operated aircraft using functional near-infrared spectroscopy.

BMC Neurol 2022 Apr 30;22(1):160. Epub 2022 Apr 30.

Department of Neurology, the First Medical Centre of Chinese PLA General Hospital, Haidian District, No.28 Fuxing Road, Beijing, 100089, China.

Background: Operating an aircraft is associated with a large mental workload; however, knowledge of the mental workload of ROV operators is limited. The purpose of this study was to establish a digital system for assessing the mental workload of remotely operated vehicle (ROV) operators using hemodynamic parameters, and compare results of different groups with different experience levels.

Method: Forty-one trainee pilots performed flight tasks once daily for 5 consecutive days in a flight simulation. Read More

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A method for continuous study of soaring and windhovering birds.

Sci Rep 2022 Apr 29;12(1):7038. Epub 2022 Apr 29.

RMIT University, Melbourne, Australia.

Avian flight continues to inspire aircraft designers. Reducing the scale of autonomous aircraft to that of birds and large insects has resulted in new control challenges when attempting to hold steady flight in turbulent atmospheric wind. Some birds, however, are capable of remarkably stable hovering flight in the same conditions. Read More

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3D Conformal Fabrication of Piezoceramic Films.

Adv Sci (Weinh) 2022 Apr 28:e2106030. Epub 2022 Apr 28.

Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China.

Piezoceramic films are an essential class of energy-conversion materials that have been widely used in the electronics industry. Although current methods create a great freedom for fabricating high-quality piezoceramic films, it requires well-controlled synthesis conditions, including special high-cost equipment and planar substrates particularly. The limited substrate selections hinder the applications of piezoceramic films in 3D conformal structures where most objects possess complex curvilinear surfaces. Read More

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Human drone interaction in delivery of medical supplies: A scoping review of experimental studies.

PLoS One 2022 28;17(4):e0267664. Epub 2022 Apr 28.

Health Service Research Working Group | Acute Care, Department of Internal Medicine, Faculty of Medicine, University Medicine Halle (Saale), Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.

Background: The COVID-19 pandemic, ageing populations and the increasing shortage of skilled workers pose great challenges for the delivery of supplies for people with and without care needs. The potential of drones, as unmanned air vehicles, in healthcare are huge and are discussed as an effective new way to delivery urgent medicines and medical devices, especially in rural areas. Although the advantages are obvious, perspectives of users are important particularly in the development process. Read More

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