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El Segundo, CA, United States

Wyle is a privately held provider of specialized engineering, scientific and technical services to the Department of Defense, NASA, and a variety of commercial customers primarily in the aerospace industry. The Company offers services in the areas of test and evaluation; systems engineering and information technology; life cycle and acquisition program management; life sciences research; space medical operations and engineering; and qualification testing for systems and components.Founded in 1949, the Company is still headquartered in El Segundo, California, and has approximately 4,800 employees at more than 50 facilities nationwide. Wyle comprises three primary operating entities: Aerospace Group, CAS Group, and Integrated Science and Engineering Group. Annual revenue is approximately $1.1 billion. Wikipedia.

Hakkinen S.,NASA | Rhines P.B.,University of Washington | Worthen D.L.,Wyle
Journal of Geophysical Research: Oceans | Year: 2011

Ocean state estimates from 1958 to 2005 from the Simple Ocean Assimilation System (SODA) system are analyzed to understand circulation between subtropical and subpolar Atlantic and their connection with atmospheric forcing. This analysis shows three periods (1960s, around 1980, and 2000s) with enhanced warm, saline waters reaching high latitudes, alternating with freshwater events originating at high latitudes. It complements surface drifter and altimetry data showing the subtropical-subpolar exchange leading to a significant temperature and salinity increase in the northeast Atlantic after 2001. The warm water limb of the Atlantic meridional overturning cell represented by SODA expanded in density/salinity space during these warm events. Tracer simulations using SODA velocities also show decadal variation of the Gulf Stream waters reaching the subpolar gyre and Nordic seas. The negative phase of the North Atlantic Oscillation index, usually invoked in such variability, fails to predict the warming and salinization in the early 2000s, with salinities not seen since the 1960s. Wind stress curl variability provided a linkage to this subtropical/subpolar gyre exchange as illustrated using an idealized two-layer circulation model. The ocean response to the modulation of the climatological wind stress curl pattern was found to be such that the northward penetration of subtropical tracers is enhanced when amplitude of the wind stress curl is weaker than normal. In this case both the subtropical and subpolar gyres weaken and the subpolar density surfaces relax; hence, the polar front moves westward, opening an enhanced northward access of the subtropical waters in the eastern boundary current. Copyright 2011 by the American Geophysical Union.

Han J.,Wyle | Pan H.-L.,National Centers for Environmental Prediction Environmental Modeling Center
Weather and Forecasting | Year: 2011

A new physics package containing revised convection and planetary boundary layer (PBL) schemes in the National Centers for Environmental Prediction's Global Forecast System is described. The shallow convection (SC) scheme in the revision employs a mass flux parameterization replacing the old turbulent diffusion-based approach. For deep convection, the scheme is revised to make cumulus convection stronger and deeper to deplete more instability in the atmospheric column and result in the suppression of the excessive grid-scale precipitation. The PBL model was revised to enhance turbulence diffusion in stratocumulus regions. A remarkable difference between the new and old SC schemes is seen in the heating or cooling behavior in lower-atmospheric layers above the PBL. While the old SC scheme using the diffusion approach produces a pair of layers in the lower atmosphere with cooling above and heating below, the new SC scheme using the mass-flux approach produces heating throughout the convection layers. In particular, the new SC scheme does not destroy stratocumulus clouds off the west coasts of South America and Africa as the old scheme does. On the other hand, the revised deep convection scheme, having a larger cloud-base mass flux and higher cloud tops, appears to effectively eliminate the remaining instability in the atmospheric column that is responsible for the excessive grid-scale precipitation in the old scheme. The revised PBL scheme, having an enhanced turbulence mixing in stratocumulus regions, helps prevent too much low cloud from forming. An overall improvement was found in the forecasts of the global 500-hPa height, vector wind, and continental U.S. precipitation with the revised model. Consistent with the improvement in vector wind forecast errors, hurricane track forecasts are also improved with the revised model for both Atlantic and eastern Pacific hurricanes in 2008. © 2011 American Meteorological Society.

Joyce R.J.,National Oceanic and Atmospheric Administration | Joyce R.J.,Wyle | Xie P.,National Oceanic and Atmospheric Administration
Journal of Hydrometeorology | Year: 2011

A Kalman filter (KF)-based Climate Prediction Center (CPC) morphing technique (CMORPH) algorithm is developed to integrate the passive microwave (PMW) precipitation estimates from low-Earth-orbit (LEO) satellites and infrared (IR) observations from geostationary (GEO) platforms. With the new algorithm, the precipitation analysis at a grid box of 8 × 8 km 2 is defined in three steps. First, PMW estimates of instantaneous rain rates closest to the target analysis time in both the forward and backward directions are propagated from their observation times to the analysis time using the cloud system advection vectors (CSAVs) computed from the GEO-IR images. The "prediction" of the precipitation analysis is then defined by averaging the forward- and backward-propagated PMW estimates with weights inversely proportional to their error variance. The IR-based precipitation estimates are incorporated if the gap between the two PMW observations is longer than 90 min. Validation tests showed substantial improvements of the KF-based CMORPH against the original version in both the pattern correlation and fidelity of probability density function (PDF) of the precipitation intensity. In general, performance of the original CMORPH degrades sharply with poor pattern correlation and substantially elevated (damped) frequency for light (heavy) precipitation events when PMW precipitation estimates are available from fewer LEO satellites. The KF-based CMORPHis capable of producing high-resolution precipitation analysis with much more stable performance with various levels of availability for the PMW observations. © 2011 American Meteorological Society.

Hung M.P.,Wyle | Lin J.,Ohio State University | Wang W.,National Oceanic and Atmospheric Administration | Kim D.,Lamont Doherty Earth Observatory | And 2 more authors.
Journal of Climate | Year: 2013

This study evaluates the simulation of the Madden-Julian oscillation (MJO) and convectively coupled equatorial waves (CCEWs) in 20 models from the Coupled Model Intercomparison Project (CMIP) phase 5 (CMIP5) in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) and compares the results with the simulation of CMIP phase 3 (CMIP3) models in the IPCC Fourth Assessment Report (AR4). The results show that the CMIP5models exhibit an overall improvement over the CMIP3 models in the simulation of tropical intraseasonal variability, especially the MJO and several CCEWs. The CMIP5 models generally produce larger total intraseasonal (2-128 day) variance of precipitation than the CMIP3 models, as well as larger variances of Kelvin, equatorial Rossby (ER), and eastward inertio-gravity (EIG) waves. Nearly all models have signals of the CCEWs, with Kelvin and mixed Rossby-gravity (MRG) and EIG waves being especially prominent. The phase speeds, as scaled to equivalent depths, are close to the observed value in 10 of the 20 models, suggesting that these models produce sufficient reduction in their effective static stability by diabatic heating. The CMIP5 models generally produce larger MJO variance than the CMIP3 models, as well as a more realistic ratio between the variance of the eastward MJO and that of its westward counterpart. About one-third of the CMIP5 models generate the spectral peak of MJO precipitation between 30 and 70 days; however, the modelMJO period tends to be longer than observations as part of an overreddened spectrum, which in turn is associated with too strong persistence of equatorial precipitation. Only one of the 20 models is able to simulate a realistic eastward propagation of the MJO. © 2013 American Meteorological Society.

Husaini S.,Wyle | Husaini S.,Air Force Research Lab | Bedford R.G.,Air Force Research Lab
Applied Physics Letters | Year: 2014

Here, we report on the development of an antiresonant graphene-based one-dimensional structure which allows the control of linear and nonlinear device performance through optical confinement. A record average output in excess of 10 W is achieved by integrating this antiresonant graphene saturable absorber mirror into a vertical-external-cavity-surface-emitting-laser at 1030 nm, which leads to strong evidence of mode-locking, generating pulses with energies up to 2.8 nJ and a pulsewidth of 353 fs. © 2014 AIP Publishing LLC.

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