Conferences, Lectures, & Seminars
Events for April
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Seismic Analysis and Protection of Highway Bridges Including Soil-Structure Interaction I
Mon, Apr 03, 2006 @ 11:00 AM - 11:50 AM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:
Jian Zhang
Department of Civil Engineering
University of California Los AngelesAbstract: This seminar presents results from my doctoral studies that examine the efficiency of supplemental energy dissipation devices to suppress the seismic response of highway bridges. Recognizing that soil-structure interaction affects appreciably the earthquake response of highway overcrossings, the study concentrates on the development and validation of a simple yet dependable method to estimate the seismic response of freeway overcrossings. Firstly, approximate analytical solutions and finite element results are compared to conclude on a simple procedure that allows for the estimation of the kinematic response functions and dynamic stiffnesses of approach embankments. Secondly, the study proceeds with the validation of a step- by-step analysis procedure through two case studies of instrumented conventional highway bridges. The proposed method adopts the substructure approach where all dynamic stiffnesses of approach embankments and pile groups are approximated with frequency-independent springs and dashpots. Excellent agreement between the simulated and recorded response has been achieved using the proposed procedure. Finally, the proposed procedure is used to analyze the seismic response of a newly constructed freeway overcrossing that is equipped with energy dissipation devices. The nonlinear behavior of columns as well as hysteretic behavior of seismic protection devices (elastomeric bearings and viscous fluid dampers) are included. The emphasis is placed to understand the effect of supplemental damping in association with the ability of the structure to dissipate energy through soil-structure-interaction. It is concluded that the as-built supplemental energy dissipation devices are partially effective in controlling displacement demands for this model bridge when soil-structure-interaction effect is included. In some occasions the bridge with protection devices under performs the bridge with conventional design (i.e. integral abutment). Soil-structure interaction is partially responsible for reducing the efficiency of the protection devices. --------------------------------------------------------------------------------Location: Kaprielian Hall (KAP) - 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Digital Image Correlation to Evaluate Particle-Scale Deformation in Sand
Tue, Apr 04, 2006 @ 12:00 PM - 12:50 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:Roshanak VarjavandUSC, CE Graduate Student
Location: Kaprielian Hall (KAP) - rielian Hall, Room 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Getting the Big Picture: Cyberinfrastructure and its Role in System-Oriented Science
Fri, Apr 07, 2006 @ 11:00 AM - 11:50 AM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Carl Kesselman
USC - Information Science Institute
April 7th, 2006 Cyberinfrastructure offers the promise of enabling scientific discovery at a scale not otherwise possible. By leveraging these infrastructure advances, it is not only possible to model phenomena with more detail then previously possible, but also to understand the behavior of increasingly more complex systems. For example, in the Southern California Earthquake Center, we combine models for rupture dynamics, fault systems, and wave propagation to determine what surface motion we are likely to see at various points in Southern California. The goal is to not only model the response of the earth, but also to couple it with the bridges and buildings on the surface to create a complete system model of Los Angeles from the perspective of understanding earthquake response. The potential of such systems-oriented science is one of the biggest benefits that cyberinfrastructure can bring. These complex models for system-level science draw on many aspects of our information technology infrastructure, including numerical simulation on high-performance computers, data bases, access to sensor networks, knowledge-based systems, and data mining to name but a few. Hence the issues facing the scientist are more then simply "writing a program" but rather on how components and resources can be flexibly integrated to a computational system that addresses the scientific problem being explored. This flexible integration is one of the primary objectives behind the creation of cyberinfrastructure in general, and the motivation behind Grid infrastructure in particular. In this talk, I will describe the creation of a large-scale cyberinfrastructure and illustrate with the Globus Toolkit, which is a widely deployed Grid infrastructure. I will discuss a range of different applications that are currently leveraging this infrastructure. Finally, I will identify some of the future directions and challenges that remain in order to achieve the potential from systems-level science from the perspective of core computer science research as well as domain-specific advances.Location: Kaprielian Hall (KAP) - rielian Hall, Room 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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An overview of current air pollution control strategy on in-use light and medium duty vehicle in Ca
Fri, Apr 07, 2006 @ 01:00 PM - 02:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Jerry Ho, Staff Air Pollution Specialist and
Air Resources Engineer
El Monte, CAABSTRACT: The State of California use different air pollution control strategies between newer and older vehicles. Since most of the new vehicles for sale in California with On Board Diagnostic (OBD) generate very low emissions from tailpipe, the emission impact from the older vehicles become more significant over time. ARB estimated that evaporative emissions will soon surpass tailpipe emissions from all vehicle source in 2010. New effort will be focused on evaporative emissions control for the older vehicles in California.Location: Kaprielian Hall (KAP) - rielian Hall 156
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Multifunctional Materials: A New Horizon in Engineering Science
Mon, Apr 10, 2006 @ 11:00 PM - 11:50 AM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:Prof. Sia Nemat-Nasser
Department of Mechanical and Aerospace Engineering
Center of Excellence for Advanced Materials
9500 Gilman Drive, La Jolla, CA 92093-0416
University of California San DiegoAbstract:Multifunctional materials and structures are systems designed and manufactured to possess one or more integrated functionality, in addition to their required mechanical and load-bearing attributes. Essentially all biological systems have integrated multifunctional capabilities. Few traditional structural systems are multifunctional. Development of multifunctional materials and hence structures requires a multidisciplinary approach that has been the hallmark of Engineering Science. Recent years have witnessed an avalanche of governmental initiative for research in multifunctional materials and structures. In this talk, I will review a class of multifunctional lightweight composites which have tuned electromagnetic (EM) signature management and sensing, self-crack-healing, thermal management, as well as being structurally strong and tough. The EM functionality is produced by integrating into the composite's fabric minute amounts of conductors of optimal configuration, which leads to composites with desired electric permittivity and magnetic permeability. For example, a solid composite of this kind can be tuned to have an index of refraction of 1 over a desired frequency range, rendering the solid fully EM-transparent in that frequency range. The wire conductors are integrated into the composite's fiber reinforcing braids that also include Kevlar, glass, or other desired strengthening constituents. For the matrix material, we are considering a newly developed polymer in which micro-cracks can heal, reversibly and at the molecular level, through the application of moderate heat and pressure. The conductive wires embedded in the composites can be used as resistive elements to heat the material, as sensors to detect internal damage, and as electrical conductors to tune the electromagnetic properties of the system. The next step is to add information-based properties into such multifunctional composites, mimicking nature's approach to local and global information acquisition, processing, and communication. Time permitting, the lecture will also explore some of the interwoven challenges that must be successfully met in order to create intelligently-sensing composite materials that are aware of their environmental and internal changes; and can selectively acquire, process, and store or communicate information locally and globally. Multifunctional composites of this kind enhance the role of structural materials from mere load-bearing systems to lightweight structures with many additional attributes. Short Bio:Nemat-Nasser is a Distinguished Professor of Mechanics of Materials, and has held the John Dove Isaacs Chair in Natural Philosophy (1995-2000) at UCSD, where he has been a faculty member, 1966-70, and Professor and Director of CEAM, 1985-present. As a Professor, he taught mechanics and mathematics at Northwestern University (1970-85). He was awarded the International Technology Institute's Willard Rockwell Medal in 2003, the William Prager Medal in Solid Mechanics by the Society of Engineering Science in 2002, and the ASME Nadai Medal in 2002. He was elected a member of the National Academy of Engineering in 2001, an Honorary Member of the prestigious World Innovation Foundation, in 2004, and an Honorary Member of ASME in 2005. Three times (1994-95, 1996-97, and 2000-01) he has been selected by the graduating seniors as the best teacher of the year; has supervised over 40 Ph.D. students, has authored or coauthored over 400 scientific papers, over 20 books and proceedings; has received ASME's Aerospace Division's Best Paper of the Year Award, Adaptive Structures and Materials Systems [Nemat-Nasser, S. "Micromechanics of Actuation of Ionic Polymer-metal Composites," Journal of Applied Physics, Vol. 92, No. 5 (2002) 2899-2915]; has published two major books: (1) Nemat-Nasser, S. and Hori, M., Micromechanics: Overall Properties of Heterogeneous Solids, Elsevier Science Publishers, 1st edition (1993), 730 pages; 2nd Edition (1999) 810 pages, and (2) Nemat-Nasser, S., Plasticity: A Treatise On Finite Deformation of Heterogeneous Inelastic Materials, Cambridge University Press (2004) 730 pages. His research includes: experimentally-based analytical/computational, nano-scale modeling of response and failure modes of materials, particularly multifunctional structural systems, e.g., structural composites with tunable electromagnetic functionality, thermal management, self-healing, and self-sensing; polyelectrolytes and ionic polymer metal composites as soft-actuators and sensors; shape-memory alloys; bio-hybrid interfaces and their short- and long-term functionality; advanced metals and ceramics; elastomers; granular materials; and hybrid composites. He has been consultant to many companies and has served in a number of national scientific panels. For a complete list of publications and other information, please refer to the website: http://www-mae.ucsd.edu/RESEARCH/NEMAT-NASSER/Location: Kaprielian Hall (KAP) - rielian Hall, Room 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Microbial Fuel Cells: Little Bugs Could Make a Big Difference
Fri, Apr 14, 2006 @ 01:00 PM - 02:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Orianna Bretschger
Ph.D. candidate in the Mork Family Department of Chemical Engineering and Materials Science in collaboration with the USC Geobiology program
University of Southern CaliforniaAbstract
A microbial fuel cell is a system that utilizes the catalytic activity of microbes to convert the chemical energy of fuel into electrical energy. Microbial fuel cells (MFCs) utilize a broad range of materials for fuel and a microbe (or microbial communities) as the catalyst. Given these components, MFCs are a very flexible technology that can be used in many applications. For example, MFCs have been employed in South Korea to treat waste water and yield a by-product of electricity for over 5 years! Additionally, MFC's are being explored as tools for understanding microbial physiology and are being optimized for portable power applications.
Future MFC applications will be enabled when the current densities produced by MFCs are improved, which will be dependent upon a better understanding of the molecular mechanisms involved in the microbial production of electricity. MFC design is an additional factor that must be considered for future applications. When these biological and engineering issues are fully understood and addressed, it should be possible to move up in scale to industrial applications, and down in scale to micro- and nano-applications: then MFC applications may only be limited by the imagination of the investigator!
Location: Kaprielian Hall (KAP) - rielian Hall, Room 156
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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A Digital Solid Model of the Human Liver
Tue, Apr 18, 2006 @ 12:00 PM - 12:50 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:
Brian Kannard
CE Graduate StudentLocation: Kaprielian Hall (KAP) - 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Trilinos Tutorial: Overview and Basic Concepts
Fri, Apr 21, 2006 @ 11:00 AM - 11:50 AM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Mike Heroux
Distinguished Member of Technical Staff
Numerical and Applied Mathematics Department
Sandia National LaboratoriesAbstract:
The Trilinos Project is an effort to facilitate the design, development, integration and ongoing support of mathematical software libraries within an object-oriented framework for the solution of large-scale, complex multi-physics engineering and scientific problems. Trilinos addresses two fundamental issues of developing software for these problems: (i) Providing a streamlined process and set of tools for development of new algorithmic implementations and (ii) promoting interoperability of independently developed software packages to enable solution of large-scale multi-physics problems.
Trilinos uses a two-level software structure designed around collections of packages. A Trilinos package is an integral unit usually developed by a small team of experts in a particular algorithms area such as algebraic preconditioners, nonlinear solvers, etc. Packages exist underneath the Trilinos top level, which provides a common look-and-feel, including configuration, documentation, licensing, and bug-tracking. Here we present the overall Trilinos design, illustrating the value of the package architecture. We discuss the services that Trilinos provides to a prospective package and how these services are used by various packages. We discuss how to get started using Trilinos via a simple example. We also show how packages can be combined to rapidly develop new algorithms. Finally, we discuss how Trilinos facilitates high quality software engineering practices that are increasingly required from simulation software.
Location: Kaprielian Hall (KAP) - rielian Hall, Room 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes