Conferences, Lectures, & Seminars
Events for May
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Astani CEE Dept. Seminar
Wed, May 01, 2013 @ 03:30 AM - 04:30 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Philip L-F. Liu , Class of 1912 Professor in Engineering, School of Civil and Environmental Engineering, Cornell University
Talk Title: Some Recent Advancement in Tsunami Research
Abstract: Dr. Liu plans to give a brief progress report on two on-going research projects, related to coastal effects of tsunamis.
The first problem concerns the effects of coastal forest on wave propagation and dissipation. A mathematical model for wave propagation in a lattice-like array of vertical cylinders is developed, where the macro-scale variation of waves is derived from the dynamics in the micro-scale cells. Assuming infinitesimal waves, periodic lattice configuration and strong contrast between the lattice spacing and the typical wavelength, the perturbation theory of homogenization (multiple scales) is used to derive the effective equations governing the macro-scale wave dynamics. The constitutive coefficients are computed from the solution of micro-scale boundary value problem for a finite number of unit cells. Eddy viscosity in a unit cell is determined by balancing the time averaged rate of dissipation and the rate of work done by wave force on the forest at a finite number of macro stations. While the spirit is similar to RANS scheme, less computational effort is needed. Using one fitting parameter, the theory is used to simulate three existing experiments with encouraging results. Limitations of the present theory are also pointed out.
The second research topic aims to establish the correlations among bed shear stress, the near-bed velocity and the surface elevation of a leading tsunami wave form during the run-up and down-rush. To this end, a new shear plate device is designed and constructed, consists of a small shear plate attached to the housing via vertical supports that provide a restoring force. The plate is subject to fluid shear and pressure forces and these can be measured via the displacement of the plate and pressure tapings. The average shear stress on the plate can then be calculated. Experiments have been conducted using this device on a sloping ââ¬Ëbeachââ¬â¢ at Oregon State Universityââ¬â¢s Hinsdale Wave Research Laboratory in the Long Wave Flume and in a constant depth at Cornellââ¬â¢s DeFrees Laboratory in the Small Wave Flume. The laminar bed shear stress measurements under a solitary wave agree well with the theory and existing PIV data. Bed shear stress measurements for a breaking solitary wave on a slope are collected in the surf zone and swash zone. Temporal and spatial variations of bed shear stress are correlated to the near-bed velocity and water depth.
Biography: Dr. Liu earned his bachelorââ¬â¢s degree in civil engineering from National Taiwan University, his masterââ¬â¢s degree in civil engineering from Massachusetts Institute of Technology (MIT), and his doctoral degree in hydrodynamics from MIT. Dr. Liu is the Director of the School of Civil and Environmental Engineering at Cornell University, where he has served as professor for his entire career. Dr. Liu has made major research contributions in developing water wave theories and modeling methodologies for tsunami dynamics. His research has yielded practical results including those obtained by his COMCOT (Cornell Multi-grid Coupled Tsunami) and COBRAS (Cornell Breaking Waves and Structures) models and from the field data from multiple post-tsunami field surveys, including Sri Lanka. Among his many awards, Dr. Liu received ASCEââ¬â¢s Walter L. Huber Civil Engineering Research Prize in 1978, ASCEââ¬â¢s John G. Moffatt-Frank E. Nichol Harbor and Coastal Engineering Award in 1997, and ASCEââ¬â¢s International Coastal Engineering Award in 2004. He also received a fellowship from the J.S. Guggenheim Foundation in 1980 and an Alexander von Humboldt Research Award in 2009. Dr. Liu was elected fellow of the American Geophysical Union in 2006 and is an elected ASCE distinguished member.
Host: Astani CEE Dept.
Location: Kaprielian Hall (KAP) - 209
Audiences: Everyone Is Invited
Contact: Cassie Cremeans
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Astani CEE Dept. Seminar
Thu, May 02, 2013 @ 02:00 PM - 03:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Christine Shoemaker, Joseph P. Ripley Professor, School of Civil and Environmental Engineering &Cornell University
Talk Title: Optimization of Computationally Expensive Environmental Models Including Application to Monitoring Multi-Phase Subsurface flow from Carbon Sequestration
Abstract: This talk will first give an overview of my research on optimization and uncertainty quantification and its application to a range of environmental topics. Our new algorithms (available as open source software) are very efficient for these applications and other multi-modal, computationally expensive simulation models because the algorithms are designed to reduce significantly the number of simulations required for finding the global optimal solution to a problem with multiple local minima. Our approach is to iteratively approximate the objective function or likelihood function f(x) with Radial Basis Functions (RBF) based on all previous simulations to guide the selection of the next expensive function evaluation. The applications incorporate issues related to monitoring, forecasting, uncertainty quantification, and risk analysis as well parameter estimation and design.
Estimation of sequestered CO2 and pressure plumes is very important for risk analysis but difficult because the multiphase PDE model is very nonlinear and computationally expensive, monitoring data is very sparse, and the inverse optimization problem has multiple local minima. Each objective function evaluation requires expensive forward simulation of 3-D, highly nonlinear, multi-phase, multi-constituent set of PDEs (which can take hours per simulation). Iââ¬â¢ll present results using TOUGH2 that give good current estimates and forecasts of plumes with our global optimization algorithm Stochastic RBF with a small number of original model simulations, and Iââ¬â¢ll use our SOARS algorithm to assess uncertainty.
Biography: Prof. Shoemaker received a PhD in Mathematics from USC supervised by Richard Bellman on dynamic programming and control. She is interested in surface and subsurface contaminant transport applications as well as in developing new computationally efficient distributed (HPC) optimization and control methods. Environmental topics she has worked on include watershed contaminant transport, groundwater remediation, global climate models (CLM4.5) and optimization of stochastic hydropower systems (BPA). . She is a member of the National Academy of Engineering and a Distinguished Member in ASCE. She is also a Fellow in INFORMS (Operations Research) and in AGU (hydrology).
Host: Astani CEE Dept.
Location: Kaprielian Hall (KAP) - 209
Audiences: Everyone Is Invited
Contact: Cassie Cremeans
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CEE Ph.D. Seminar
Fri, May 03, 2013 @ 04:00 PM - 05:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Nan Li and Mahmoud Kamalzare, USC Astani Department of Civil and Environmental Engineering Graduate Students
Talk Title: A Radio Frequency Based Indoor Localization Framework for Supporting Building Emergency Response Operations
Abstract:
Second Presenter:
Mahmoud Kamalzare â⬓
Ttile: ââ¬ÅComputationally Efficient Design of Optimal Strategies for Semiactive Damping Devicesââ¬Â
Pizza is served at 5:00pm in KAP 209
Location: John Stauffer Science Lecture Hall (SLH) - 102
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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CEE Ph.D. Seminar
Fri, May 10, 2013 @ 04:00 PM - 05:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Leon Alkalai, , Jet Propulsion Laboratory
Talk Title: ââ¬ÅSolar Systems Exploration - Mission Formulation Systems Engineeringââ¬Â by Leon Alkalai, JPL
Abstract: TBA
Biography: Dr. Leon Alkalai received his MSc and PhD degrees from the UCLA Computer Science Department in 1986 and 1989 respectively and has since then been working at NASAââ¬â¢s Jet Propulsion Laboratory, California Institute of Technology.
He is currently a program manager at JPL responsible for the next NASA Discovery and New Frontiers program mission portfolios as part of JPLââ¬â¢s Solar System Exploration Program Directorate.
For the first 14 years of his career at JPL, Leon worked on technology development of advanced micro-avionics and micro-systems technologies for deep-space exploration.
For the past 10 years, Leon has been in the forefront of mission formulation activities at JPL.
From 2005 â⬓ 2007 he was the JPL Capture Lead for the Gravity Recovery And Interior Laboratory (GRAIL) mission proposal which won the NASA Discovery-11 competition and successfully launched in September 2011 to the Moon.
In 2012, Leon was the Capture Lead for the InSight mission to Mars, which won the NASA Discovery-12 competition and is scheduled to launch in 2016.
Last year, NASA awarded Dr. Leon Alkalai the Individual Distinguished Achievement Medal for the successful formulation of GRAIL and for winning the Discovery-11 competition.
Leon Alkalai is an active Full Member of the International Academy of Astronautics (IAA).
Location: Seeley G. Mudd Building (SGM) - 101
Audiences: Everyone Is Invited
Contact: Evangeline Reyes