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Recent news reports stated that the National Security Agency has pursued new methods that have allowed the agency to monitor telephone and online communication, encrypted information that was thought to be virtually immune to eavesdropping. What steps can and should computer scientists take in response to this privacy threat? How will the recent revelations affect the future of cryptography—the field of encoding and decoding electronic communication and transmissions for the purposes of privacy, reliability and efficiency?
To address these questions, the Johns Hopkins University Information Security Institute will host an hour-long roundtable discussion, moderated by Anton Dahbura, interim executive director of the Information Security Institute, and Avi Rubin, the institute’s technical director. Other participants will include Johns Hopkins cyber-security experts Matthew Green, Stephen Checkoway and Giuseppe Ateniese.
The event will be streamed live at https://connect.johnshopkins.edu/jhuisicrypto/, and also will be posted online following the event.
NOTE: Seating at this public event will be limited. Members of the media who plan to cover the discussion are asked to RSVP to Phil Sneiderman, email@example.com.
Join the Department of Mechanical Engineering for the 22nd annual James F. Bell Memorial Lecture in Continuum Mechanics. Frans Spaepen, the John C. and Helen F. Franklin Professor of Applied Physics at Harvard University, will present “Mechanical Properties of Colloidal Crystals.” The lecture begins at 3 p.m. in 210 Hodson Hall on Thursday, October 27. A reception will follow in the second floor lobby area of Hodson Hall.
Colloidal particles in suspension can form liquid, crystalline and glassy phases similar to those formed by atoms. Since the particles are “fat” (~1µm) and “slow” (~0.1s), they can be individually tracked in space and time by confocal microscopy. Dense colloidal systems therefore serve as “analog computers” to study the mechanics of crystals and glasses. Colloidal crystals and glasses have small (~ mPa) but non-zero elastic constants of largely entropic origin, which can be measured in a number of ways, for example from thermal fluctuations or variations in lattice constant. The non-zero stiffness of these phases creates elastic stress fields that can interact. This will be illustrated by observations of the nucleation and propagation of misfit dislocations during the epitaxial growth of colloidal single crystals. Nucleation and propagation of dislocations upon plastic deformation, such indentation, as well as their interaction with grain boundaries can be observed directly. By measuring the local strain fields in glasses, the Eshelby-like shear transformations that govern plastic deformation in these structures can be identified, and their dynamics can be observed directly.
Frans Spaepen is the John C. and Helen F. Franklin Professor of Applied Physics at Harvard University. He received his undergraduate degree in Metallurgical Engineering at the K.U. Leuven in 1971, and a PhD in Applied Physics from Harvard University in 1975. He joined the faculty of the Division of Applied Sciences at Harvard in 1977 as Assistant Professor, was appointed Associate Professor in 1981, and Full Professor in 1983. From 1990 till 1998 he was Director of the Harvard Materials Research Laboratory/Materials Research Science and Engineering Center. From 2002 to 2013 he was the Director of the Rowland Institute at Harvard. In 2008-9 he was Interim Dean of the School of Engineering and Applied Sciences and in 2009-10 Interim Director of Center for Nanoscale Systems. His research interests span a wide range of experimental and theoretical topics in materials science, such as amorphous metals and semiconductors (viscosity, diffusion, mechanical properties), the structure and thermodynamics of interfaces (crystal/melt, amorphous/crystalline semiconductors, grain boundaries), mechanical properties of thin films, the perfection of silicon crystals for metrological applications, and colloidal systems as models for the study of dynamics and defects in crystals and glasses.
Laurent Younes, professor and chair of the Department of Applied Mathematics and Statistics at Johns Hopkins University, will present “Change Point Estimation of Brain Shape Data in Relation with Alzheimer’s Disease.”
Abstract: The manifestation of an event, such as the onset of a disease, is not always immediate and often requires some time for its repercussions to become observable. Slowly progressing diseases, and in particular neuro-degenerative disorders such as Alzheimer’s disease (AD), fall into this category. The manifestation of such diseases is related to the onset of cognitive or functional impairment and, at the time when this occurs, the disease may have already had been affecting the brain anatomically and functionally for a considerable time. We consider a statistical two-phase regression model in which the change point of a disease biomarker is measured relative to another point in time, such as the manifestation of the disease, which is subject to right-censoring (i.e., possibly unobserved over the entire course of the study). We develop point estimation methods for this model, based on maximum likelihood, and bootstrap validation methods. The effectiveness of our approach is illustrated by numerical simulations, and by the estimation of a change point for atrophy in the context of Alzheimer’s disease, wherein it is related to the cognitive manifestation of the disease. This work is a collaboration with Marilyn Albert, Xiaoying Tang and Michael Miller, and was partially supported by the NIH.
For those who cannot make it to the Homewood campus, the seminar will be video-conferenced to Traylor 709 on the School of Medicine campus.
For those who attend at Homewood, lunch will be provided at noon.
The Johns Hopkins Department of Mechanical Engineering hosts the 23rd Annual James F. Bell Memorial Lecture in Continuum Mechanics. Subra Suresh, president-designate and Distinguished University Professor ad the Nanyang Technological University, will present “Study of Human Diseases at the Intersections of Engineering, Sciences, and Medicine.”