Simulation of Runway Operations with Application of Dynamic Wake Separations to Study Runway Limitations

This paper presents an evaluation of runway operations at Chicago O’Hare International Airport to estimate the impact of proposed wake vortex separation including Recategorization Phase II and III dynamic separations. The evaluation uses a Monte Carlo simulation model that considers arrival and departure operations. The simulation accounts for static and dynamic wake vortex separations, aircraft fleet mix, runway occupancy times, aircraft approach speeds, aircraft wake circulation capacity, environmental conditions, and operational error buffers. Airport data considered for this analysis are based on Airport Surface Detection Equipment Model X records from Chicago O’Hare International Airport from January to November 2016. Dynamic wake separations are tailored to each unique set of conditions by using environmental and aircraft performance parameters as input and allowing aircraft to be exposed to the same wake vortex strength as in Recategorization Phase II (RECAT II). The analysis shows that further reductions beyond RECAT II for aircraft pairs separated by 2 nautical miles or less is not operationally feasible. These wake separations already result in little to no wake dependency. When this is the case, the challenges in wake separation are to meet runway occupancy times and to make sure aircraft separations allow for human operational variations without resulting in aircraft turnarounds or double-aircraft-occupancy runway violations.

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An evaluation of the impact of wake vortex re-categorization: The case of Charlotte Douglas International airport (CLT)

Transportation Research Part A Policy and Practice ◽

10.1016/j.tra.2018.01.013 ◽

2018 ◽

Vol 109 ◽

pp. 41-49 ◽

Cited By ~ 1

Author(s):

Tony Diana

Keyword(s):

Wake Vortex ◽

International Airport ◽

The Impact

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The Generation and Detection of Sound Emitted by Aircraft Wake Vortices in Ground Effect

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech1718.1 ◽

2005 ◽

Vol 22 (5) ◽

pp. 543-554 ◽

Cited By ~ 2

Author(s):

William L. Rubin

Keyword(s):

Ground Effect ◽

Aircraft Noise ◽

Wake Vortex ◽

Wind Noise ◽

Vortex Sound ◽

Wake Vortices ◽

International Airport ◽

Aircraft Landing ◽

Aircraft Wake ◽

Noise Spectra

Abstract Sound recorded by the author in March 2002 at JFK International Airport shows that wake vortices in ground effect emit infrasound that is 1) more than 40 dB stronger than audible wake vortex sound; 2) substantially stronger than the infrasound component of wind noise and airport noise; and 3) comparable to, and often stronger than, the infrasound component of aircraft noise. Spectra and time plots of the magnitude of wake-vortex-generated sound are presented for aircraft landing on JFK runway 31R.

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Targeted Therapy for Metastatic Renal Cell Carcinoma

Journal of Clinical Oncology ◽

10.1200/jco.2006.08.5415 ◽

2006 ◽

Vol 24 (35) ◽

pp. 5601-5608 ◽

Cited By ~ 221

Author(s):

Robert J. Motzer ◽

Ronald M. Bukowski

Keyword(s):

Renal Cell Carcinoma ◽

Targeted Therapy ◽

Cell Carcinoma ◽

Phase Ii ◽

Renal Cell ◽

Progression Free Survival ◽

Targeted Agents ◽

Cell Renal Cell Carcinoma ◽

Phase Ii And Iii ◽

The Impact

The discovery of a relationship for the VHL tumor suppressor gene, hypoxia inducible factor-1 alpha, and vascular endothelial growth factor in the growth of clear-cell renal cell carcinoma (RCC) has identified a pathway for novel targeted therapy. This study evaluated the impact of these agents on metastatic RCC (mRCC), and highlights recent phase II and III trials. A systematic review examined the clinical data for novel targeted agents in mRCC, with a focus on randomized phase II and III trials of the novel targeted agents sunitinib, temsirolimus, sorafenib, and bevacizumab. Several agents, including the small-molecule targeted inhibitors sunitinib, temsirolimus, sorafenib, and the monoclonal antibody bevacizumab, have demonstrated antitumor activity in randomized trials. Superior activity was found with sunitinib and temsirolimus versus cytokines in first-line therapy. Improved progression-free survival was reported with sorafenib and bevacizumab given second-line compared with placebo. Targeted therapies show promising activity in this disease, and they have been changing patient management. Sunitinib and sorafenib were recently approved by the US Food and Drug Administration for treatment of mRCC, These drugs are currently included in clinical practice.

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Aircraft Wake Vortex Measurements at Denver International Airport

10th AIAA/CEAS Aeroacoustics Conference ◽

10.2514/6.2004-2880 ◽

2004 ◽

Cited By ~ 13

Author(s):

Robert Dougherty ◽

Frank Wang ◽

Earl Booth ◽

Michael Watts ◽

Neil Fenichel ◽

...

Keyword(s):

Wake Vortex ◽

International Airport ◽

Aircraft Wake

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Life-Cycle Costs of Selected Uniformed Health Professions (Phase II: The Impact of Constraints and Policies on the Optimal-Mix-of-Accession Model)

10.21236/ada413788 ◽

2003 ◽

Author(s):

Shayne Brannman ◽

Eric W. Christensen ◽

Ronald H. Nickel ◽

Cori Rattelman ◽

Richard D. Miller

Keyword(s):

Life Cycle ◽

Phase Ii ◽

Health Professions ◽

Life Cycle Costs ◽

Optimal Mix ◽

The Impact

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Study on the influence of linear and nonlinear distribution of crosswind on the motion of aircraft wake vortex

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410020987430 ◽

2021 ◽

pp. 095441002098743

Author(s):

Dong Li ◽

Ziming Xu ◽

Ke Zhang ◽

Zeyu Zhang ◽

Jinxin Zhou ◽

...

Keyword(s):

Numerical Simulations ◽

Dissipation Rate ◽

Vortex Pair ◽

Vertical Shear ◽

Wake Vortex ◽

Analysis Method ◽

Velocity Magnitude ◽

Aircraft Wake ◽

Linear And Nonlinear ◽

Nonlinear Distribution

Environmental crosswind can greatly affect the development of aircraft wake vortex pair. Previous numerical simulations and experiments have shown that the nonlinear vertical shear of the crosswind velocity can affect the dissipation rate of the aircraft wake vortex, causing each vortex of the vortex pair descent with different velocity magnitude, which will lead to the asymmetrical settlement and tilt of the wake vortex pair. Through numerical simulations, this article finds that uniform crosswind convection and linear vertical shear crosswind convection can also have an effect on the strength of the vortex. This effect is inversely proportional to the cube of the vortex spacing, so it is more intense on small separation vortex pair. In addition, the superposition of crosswind and vortex-induced velocities will lead to the asymmetrical pressure distribution around the vortex pair, which will also cause the tilt of the vortex pair. Furthermore, a new analysis method for wake vortex is proposed, which can be used to predict the vortex trajectory.

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Left ventricular remodeling: is there a real impact of cardiac rehabilitation?

European Journal of Preventive Cardiology ◽

10.1093/eurjpc/zwab061.366 ◽

2021 ◽

Vol 28 (Supplement_1) ◽

Author(s):

NPD Cunha ◽

I Aguiar-Ricardo ◽

T Rodrigues ◽

P Silverio Antonio ◽

S Couto Pereira ◽

...

Keyword(s):

Exercise Training ◽

Left Ventricle ◽

Cardiac Rehabilitation ◽

Phase Ii ◽

Left Ventricular ◽

Cardiac Resynchronization ◽

Left Ventricular Ejection ◽

Ventricular Ejection Fraction ◽

Ischemic Disease ◽

The Impact

Abstract Funding Acknowledgements Type of funding sources: None. Introduction A number of randomized controlled trials have examined the effect of exercise training on left ventricle (LV) remodeling in individuals with cardiovascular disease. However, the results of these trials have been inconclusive. Purpose Evaluation of the impact of a cardiac rehabilitation program (CRP) on left ventricle remodelling evaluated by echocardiogram. Methods Observational single centre study including consecutive patients, undergoing structured CRP since June 2016 until February 2020. Phase II CRP included 3 months of exercise training, aerobic and strength exercise, individually prescribed, 3 times a week, 60 minutes sessions. All patients were submitted to a clinical evaluation, echocardiogram, and cardiopulmonary exercise test before and after the CRP. Results 205 patients (62.6 ± 11 years, 83.4% men, 82.3% ischemic disease) were included in a phase II CRP. Most patients had ischemic disease (82.3%) and 23.5% of patients had left ventricular ejection fraction (LVEF) <40%. Of the cardiovascular risk factors, hypertension was the most prevalent (76%), followed by dyslipidaemia (67.4%), active smoking (45.9%) and diabetes (26.9%). After the CRP, there was a significant improvement of LVEF (from 48.3 ± 13 to 52 ± 11.6 %, p = 0.001) and a significant reduction of LV volumes (LV end-diastolic volume, LVEDV , decreased from 140 ± 81 to 121 ± 57, p = 0.002; LV end-systolic volume , LVESV , reduced from 80 ± 75 to 64 ± 48, p = 0.004). Considering only the patients with LVEF < 40% (n = 38), the improvement was even greater: LVEF increased from 30 ± 8 to 39 ± 13 (p = 0.002); LVEDV reduced from 206 ± 107 to 159 ± 81 (p = 0.001) and LVESV reduced from 142 ± 99 to 101 ± 66 (p = 0.002). 63.6%(n = 14) of these patients improved at least 10% of LVEF and only 1 of them had a cardiac resynchronization therapy device. Conclusions A phase II CR program was associated with significant improvements in left ventricular reverse remodelling irrespective of baseline EF classification. Those with reduced baseline EF derived an even greater improvement, highlighting the great importance of CR in this subgroup of patients.

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