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Seattle, WA, United States

Seattle University , commonly referred to as Seattle U, is a Jesuit Catholic university in the northwestern United States, located in the Capitol Hill neighborhood of Seattle, Washington.SU is the largest independent university in the Northwest US, with over 7,500 students enrolled in undergraduate and graduate programs within eight schools, and is one of 28 member institutions of the Association of Jesuit Colleges and Universities. In its "Best Colleges 2015" edition, U.S. News & World Report ranked Seattle University the 5th best school in the West, a category for institutions that offer a full range of programs up to master's degree and some doctoral programs. Seattle University School of Law has the #1 legal writing program in the nation, a rank held for six consecutive years. In 2014, Bloomberg Businessweek ranked Seattle University #1 in the nation for macroeconomics.Among all colleges nationally, Seattle University graduates, with a degree in either the Liberal Arts or science, are the 10th highest paid in the country. Wikipedia.

Smith-Pardo J.P.,Seattle University
Engineering Structures | Year: 2012

This manuscript presents the development of charts that structural engineering practitioners can use to quickly quantify the restraining effect at the bases of columns and walls supported on shallow foundations. The formulation is derived based on compatibility, equilibrium, and a simplified constitutive relation that uses two basic parameters to characterize the soil-foundation: the subgrade modulus - the stiffness parameter and the ultimate bearing capacity - the strength parameter. The model captures the intrinsic non-linear behavior of the soil with increasing loading, and the coupling between moments and axial loads. Using the proposed charts, calculated rocking responses for rigid footing models under combined axial load and moment are found to compare reasonably well with experimental results. © 2011 Elsevier Ltd. Source

Bretherton C.S.,Seattle University
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2015

Cloud feedbacks are a leading source of uncertainty in the climate sensitivity simulated by global climate models (GCMs). Low-latitude boundarylayer and cumulus cloud regimes are particularly problematic, because they are sustained by tight interactions between clouds and unresolved turbulent circulations. Turbulence-resolving models better simulate such cloud regimes and support the GCM consensus that they contribute to positive global cloud feedbacks. Large-eddy simulations using sub-100m grid spacings over small computational domains elucidate marine boundary-layer cloud response to greenhouse warming. Four observationally supported mechanisms contribute: 'thermodynamic' cloudiness reduction from warming of the atmosphere-ocean column, 'radiative' cloudiness reduction from CO2- and H2O-induced increase in atmospheric emissivity aloft, 'stability-induced' cloud increase fromincreased lower tropospheric stratification, and 'dynamical' cloudiness increase from reduced subsidence. The cloudiness reduction mechanisms typically dominate, giving positive shortwave cloud feedback. Cloudresolving models with horizontal grid spacings of a few kilometres illuminate how cumulonimbus cloud systems affect climate feedbacks. Limited-area simulations and superparameterized GCMs show upward shift and slight reduction of cloud cover in a warmer climate, implying positive cloud feedbacks. A global cloud-resolving model suggests tropical cirrus increases in a warmer climate, producing positive longwave cloud feedback, but results are sensitive to subgrid turbulence and ice microphysics schemes. © 2015 The Author(s) Published by the Royal Society. All rights reserved. Source

Studies have shown that the unpredictability and variability of wind power is reduced in systems with large numbers of geographically diverse wind plants. These effects are caused by the decreased correlation of power output between wind plants as their separation and diversity in terrain increases. One way that system operators have increased geographic diversity is by enlarging balancing areas through the physical or administrative connection of adjacent systems. This strategy can be extended from the regional level to the transcontinental level. As such, it is important to study the correlation and statistical characteristics of aggregate wind power between large, distant systems. This paper analyzes multi-year historical data from four North American system operators - Bonneville Power Administration, Electric Reliability Council of Texas, Midwest Independent Transmission System Operator and PJM - to see how effective transcontinental interconnection of systems is at enabling wind plant integration. The effects of separation and timescale on correlations of instantaneous and hourly variations are analyzed. The analysis is complemented by a study of a hypothetical transcontinental connection of the systems across yearly, monthly, daily and hourly timescales. The results show that correlations between large systems exhibit similar characteristics as the correlations between individual wind plants, but are somewhat larger in magnitude. The transcontinental system exhibits a close to normal distribution of power output and decreased variability, but there is still appreciable and statistically significant correlation at the longer timescales driven by seasonal and diurnal forcing, as well as synoptic weather systems. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd. Source

When modeling wind power from several sources, consideration of the dependency structure of the sources is of critical importance. Failure to appropriately account for the dependency structure can lead to unrealistic models, which may result in erroneous conclusions from wind integration studies and other analyses. The dependency structure is fully described by the multivariate joint distribution function of the wind power. However, few - if any - explicit joint distribution models of wind power exist. Instead, copulas can be used to create joint distribution functions, provided that the selected copula family reasonably approximates the dependency structure. Unfortunately, there is little guidance on which copula family should be used to model wind power. The purpose of this paper is to investigate which copula families are best suited to model wind power dependency structures. Bivariate copulas are considered in particular. The paper focuses on power from wind plants - collections of wind turbines with a common interconnection point - but the methodology can be generally extended to consider power from individual wind turbines or even aggregate wind power from entire systems. Twelve Archimedean and elliptical copulas are evaluated using hourly data from 500 wind plant pairs in the National Renewable Energy Laboratory's Eastern Dataset. The evaluation is based on χ2 and Cramér-von Mises statistics. Application guidelines recommending which copula family to use are developed. It is shown that a default assumption of Gaussian dependence is not justified and that the use of Gumbel copulas can result in improved models. An illustrative example shows the application of the guidelines to model dependence of wind power sources in Monte Carlo simulations. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd. Source

Sushkov A.O.,Yale University | Kim W.J.,Seattle University | Dalvit D.A.R.,Los Alamos National Laboratory | Lamoreaux S.K.,Yale University
Nature Physics | Year: 2011

Quantum theory predicts the existence of the Casimir force between macroscopic bodies, a force arising from the zero-point energy of electromagnetic field modes around them. A thermal Casimir force, due to thermal rather than quantum fluctuations of the electromagnetic field at finite temperature, was theoretically predicted long ago. Here we report the experimental observation of the thermal Casimir force between two gold plates. We measured the attractive force between a flat and a spherical plate for separations between 0.7μm and 7μm. An electrostatic force caused by potential patches on the plates' surfaces is included in the analysis. Previous measurements of the quantum-fluctuation-induced force have been unable to clearly settle the question of whether the correct low-frequency form of the dielectric constant dispersion for calculating Casimir forces is the Drude model or the plasma model. Our experimental results are in excellent agreement (reduced χ2 of 1.04) with the Casimir force calculated using the Drude model, including the T=300 K thermal force, which dominates over the quantum fluctuation-induced force at separations greater than 3μm. The plasma model result is excluded in the measured separation range. © 2011 Macmillan Publishers Limited. All rights reserved. Source

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