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Vortex-Free Flight Corridors for Aircraft Executing Compressed Landing Operations

Vernon J. Rossow
2006 Journal of Aircraft  
, and in-service performance of the materials, particularly regarding the cause and nature of damage that may be sustained.  ...  Integration of corridors and buffer zones into existing air-traffic management systems and procedures at airports is being studied by others [15-19].  ... 
doi:10.2514/1.21614 fatcat:z3qlpwx6w5gkfeigblbchiy7ge

Mathematical Models and Computer Simulations of Aerial Spraying and Droplets Distribution in a Target Site

Robert S. Rowiński
2019 Transactions on Aerospace Research  
The results of experimental studies were presented and compared with theoretical calculations.  ...  Mathematical models describing aerial spraying and the distribution of liquid droplets on a target were presented.  ...  Determination of optimal conditions for aerial spraying and identification of buffer zones. 4. Competence of pilots.  ... 
doi:10.2478/tar-2019-0015 fatcat:frycju52dbby7ko6qx4sxsskle

Far field wake vortex evolution of two aircraft formation flight and implications on young contrails

S. Unterstrasser, A. Stephan
2020 Aeronautical Journal  
Even though the case-by-case variability of the wake vortex behaviour across the various formation flight scenarios is large, the final plume dimensions after vortex dissolution are in general substantially  ...  Large-eddy simulations (LES) have been employed to investigate the far-field four-vortex wake vortex evolution over 10min behind an aircraft formation.  ...  Computational resources for EULAG-LCM simulations were made available by the German Climate Computing Center (DKRZ) through support from the German Federal Ministry of Education and Research (BMBF) and  ... 
doi:10.1017/aer.2020.3 fatcat:f5d4rc5aanbsjhsad6fgofiiue

Safe Zone for Closely Spaced Parallel Approaches

Steven J. Landry, Alfred Lynam
2011 Journal of Guidance Control and Dynamics  
GUIDANCE, VOL. 34, NO. 2: consider wake; extensions to downwind cases can be handled by predicting the position of the wake vortex and adjusting the protection time or by actively avoiding the wake [19  ...  Inside of 2500 ft, the runways are considered dependent, and standard wake vortex separation of at least 2.5 n mile longitudinally must be provided.  ... 
doi:10.2514/1.52567 fatcat:i7pb333sb5hndbfriplm6brksa

Rotor Design for Diffuser Augmented Wind Turbines

Søren Hjort, Helgi Larsen
2015 Energies  
Then, power efficiency versus thrust is computed with the swirled actuator disk (AD) code for low and high values of tip-speed ratios (TSR), for different centerbodies, and for different spanwise rotor  ...  We address high-performance diffusers, and investigate the design requirements for a DAWT rotor to efficiently convert the available energy to shaft energy.  ...  the expansion of the surrounding wake causes a sustained low pressure along and past the centerbody, thereby reducing the risk of surface stall and/or vortex breakdown.  ... 
doi:10.3390/en81010736 fatcat:otwcyd6umvginltqdnec3kysue

Big data analysis of irregular operations: Aborted approaches and their underlying factors

L. Sherry, Zhenming Wang, H. K. Kourdali, J. Shortle
2013 2013 Integrated Communications, Navigation and Surveillance Conference (ICNS)  
These procedures serve as "pressure release valves" and in this way are symptoms of the occurrence of infrequent phenomena that impact efficiency and safety margins.  ...  OOOI data) that is the basis for NAS performance analysis today.  ...  The final section provides a discussion of the implications of these results and future work.  ... 
doi:10.1109/icnsurv.2013.6548548 fatcat:n6kcskioxfgoxoenpyhul4lhby

Flow-induced vibrations of in-line cylinder arrangements at low Reynolds numbers

Kintak Raymond Yu, Stéphane Étienne, Yves-Marie Scolan, Alexander Hay, Emmanuel Fontaine, Dominique Pelletier
2016 Journal of Fluids and Structures  
and support.  ...  In a brief investigation, numerically showed that three freely oscillating cylinders arranged in-line, in a uniform flow at the Reynolds number of Re = 200 and at a fixed reduced velocity of U r = 8, can  ...  The implication from the findings may ultimately demand a revision of the safety best practice for offshore engineering riser interference.  ... 
doi:10.1016/j.jfluidstructs.2015.10.005 fatcat:gkimb36b4vhzhmucrxumhzrcca

Agent-Based Assessment of Trajectory-Oriented Operations with Limited Delegation

Todd Callantine, Everett Palmer, Jeff Homola, Joey Mercer, Thomas Prevot
2006 2006 ieee/aiaa 25TH Digital Avionics Systems Conference  
The results indicate the concept represents an advance toward higher-efficiency NGATS operations, and emphasize the importance of shared information and air traffic controller decision support tools.  ...  The assessment focuses on how controller strategies and automation tools impact CDA operations.  ...  For aircraft scheduled at their wake vortex separation with no extra buffer, the fifteen second tolerance means a slight speed adjustment may still be required at some point before landing.  ... 
doi:10.1109/dasc.2006.313662 fatcat:jwuymgprw5c2jmzzq67kajgwki

Vortex Trapping Cavity on Airfoil: High-Order Penalized Vortex Method Numerical Simulation and Water Tunnel Experimental Investigation

Dominik Błoński, Katarzyna Strzelecka, Henryk Kudela
2021 Energies  
Apart from performing flow analysis, drag and lift coefficients for different shapes were measured to assess the effect of vortex trapping cavity on aerodynamic performance.  ...  The purpose of this article is to investigate the fundamentals of the vortex trapping cavity.  ...  In this paper, the authors try to present the impact of a vortex trapping cavity on airfoil performance.  ... 
doi:10.3390/en14248402 fatcat:5mopr2n2vjdsbmmxky6mq7wjyq

Mass-Dependent Integral Curves in Unsteady Vector Fields

Tobias Günther, Alexander Kuhn, Benjamin Kutz, Holger Theisel
2013 Computer graphics forum (Print)  
We demonstrate the applicability of our method, using a number of real-world and artificial data sets, in which mass is a crucial parameter.  ...  This comprises the extension of common concepts, i.e., path lines, streak lines, and time lines.  ...  Especially the wake of the rotor is influenced, hindered and deflected by the ground. This flow regime is known to be highly unsteady and threedimensional.  ... 
doi:10.1111/cgf.12108 fatcat:ddj5pwjd3rdppplrzpuusxng6y

Presence and Seeding Activity of Pathological Prion Protein (PrPTSE) in Skeletal Muscles of White-Tailed Deer Infected with Chronic Wasting Disease

Martin L. Daus, Johanna Breyer, Katja Wagenfuehr, Wiebke M. Wemheuer, Achim Thomzig, Walter J. Schulz-Schaeffer, Michael Beekes, Jason Bartz
2011 PLoS ONE  
The presence and seeding activity of PrP TSE in skeletal muscle from CWD-infected cervids suggests prevention of such tissue in the human diet as a precautionary measure for food safety, pending on further  ...  Here, we report for the first time a direct biochemical demonstration of pathological prion protein PrP TSE and of PrP TSE -associated seeding activity, the static and dynamic biochemical markers for biological  ...  Wasting Disease (CWD) transmission to humans using non-human primates'' of the Alberta Prion Research Institute (APRI) as a part of which this study was carried out.  ... 
doi:10.1371/journal.pone.0018345 pmid:21483771 pmcid:PMC3069970 fatcat:wpnt6a7uxrc7rnayoehn2aszfa

Quantification of histamine in various fish samples using square wave stripping voltammetric method

Ummihan Taskoparan Yilmaz, Derya Inan
2015 Journal of food science and technology  
to check fish quality and health safety. ✓ Determination of histamine in canned anchovy, frozen tinca tinca and cyprinus carpio fish samples  ...  The effect of common excipients and metal ions on the peak height of Cuhistamine complex peak was studied.  ...  Five grams of previously homogenized various fish samples were weighed out into test tube and 40 mL of distilled water added; the mixture was vortex, stirred for 5 min and then placed in an ultrasound  ... 
doi:10.1007/s13197-015-1748-9 pmid:26396415 pmcid:PMC4573168 fatcat:juxwgagkercfxb6u2dhq5cyyrm

Pilot Study: Nutritional and Preclinical Safety Investigation of Fermented Hispidin-Enriched Sanghuangporus sanghuang Mycelia: A Promising Functional Food Material to Improve Sleep

I-Chen Li, Fang-Chia Chang, Ching-Chuan Kuo, Hsin-Tung Chu, Tsung-Ju Li, Chin-Chu Chen
2022 Frontiers in Nutrition  
Despite 75 mg/kg of GKSS ethanolic extract does not affect wakefulness, rapid eye movement (REM) sleep and non-REM (NREM) sleep, GKSS ethanolic extract at 150 mg/kg significantly decreased wakefulness  ...  After the safety of GKSS is confirmed, the sleep-promoting effect of GKSS ethanolic extract enriched with hispidin was further assessed.  ...  The hexane layer was re-extract with hexane, vortex and centrifuge at 3,600 × g for 5 min.  ... 
doi:10.3389/fnut.2021.788965 pmid:35111796 pmcid:PMC8801445 fatcat:a7gr6k6sz5ecxlnn7zgukd36ty

Brodifacoum residues in fish three years after an island-wide rat eradication attempt in the tropical Pacific

Shane Siers, Aaron Shiels, Steven Volker, Kristen Rex
2020 Management of Biological Invasions  
human health and safety.  ...  Three years after ~ 18,000 kg of 25 mg/kg brodifacoum bait was broadcast across Wake Atoll to eliminate rats, we collected whole-body fish samples from six near-shore sites and one intermittently landlocked  ...  Acknowledgements The following personnel conducted fish sample collection on Wake: Thomas McAuliffe, Heather Coad, Joel Helm, George Hartzog, and Phol Srimartr. This work was funded by the Pacific Air  ... 
doi:10.3391/mbi.2020.11.1.08 fatcat:p5ru7yy2erdsjhfrmiu2oysule

Exosomes and Metabolic Function in Mice Exposed to Alternating Dark-Light Cycles Mimicking Night Shift Work Schedules

Abdelnaby Khalyfa, Valeriy A. Poroyko, Zhuanhong Qiao, Alex Gileles-Hillel, Ahamed A. Khalyfa, Mahzad Akbarpour, Isaac Almendros, Ramon Farré, David Gozal
2017 Frontiers in Physiology  
Disruptions of sleep in circadian rhythm are common in modern societies and are associated with increased risk of developing cardiometabolic disorders.  ...  Thus, gut microbiota and the cargo of plasma exosomes are altered by periodic shifts in environmental lighting, and effectively alter metabolic function, possibly via induction of systemic inflammation  ...  AUTHOR CONTRIBUTIONS AK performed experiments, analyzed data and drafted the initial version of the manuscript. VP, ZQ, AG, AAK, and MA performed experiments and analyzed data.  ... 
doi:10.3389/fphys.2017.00882 pmid:29163218 pmcid:PMC5673652 fatcat:wjgzwgixlnezzmmc5ligxasvsq
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