Dear SIAM members,
June is kicking off in high gear! This month we’re preparing for the launch of the new and improved SIAM News Online website, which consolidates all of our online news channels (SIAM News, Connect, Blogs) into one place. Plus, the Annual Meeting (AN16) countdown has begun! Find out more about these and other SIAM happenings in this month’s issue!
Quantitative radiography is an imaging technique that uses electromagnetic radiation, such as X-rays, to gather quantitative data about the interior of nontransparent objects that vary in density and composition. For example, radiography is particularly helpful when reconstructing objects composed of multiple materials, such as different types of metal. In order to generate these images, most high-energy technologies pulse X-rays through the “scene” in question; objects in the scene absorb some of the rays, while a scintillator – which measures the strength of the passing X-rays – collects the rest and fluoresces (emits visible light) in response to the collected rays. Possible scenes include parts of the human body, thermal explosions, nuclear testing sites, and other applications of national security. The resulting images directly measure the intensity of visible light, yielding information about the objects’ internal structure.
According to the Vision Council of America, roughly 75% of adults in the United States require some form of vision correction. Yet only 10% of Americans wear contact lenses. Studies estimate that one in four initial contact-users finds the lenses uncomfortable and stops wearing them. Thus, increasing the comfort level of contact lenses and expanding the market is a continual objective in the vision industry.
In order to understand the factors that contribute to lens comfort, it is important to study the solid and fluid mechanics of a lens’ interaction with an eye. In an article publishing this week in the SIAM Journal on Applied Mathematics, authors David Ross, Kara Maki, and Emily Holz design an equilibrium model to demonstrate the elastic stresses and suction pressure distribution between a soft hydrogel contact lens and an eye. Read the rest of this entry »
Image segmentation, the process of separating a digital image into multiple sections for individual examination, is frequently used in medical image analysis. For example, segmentation in ultrasound footage helps identify boundaries and regions of interest (ROI) that facilitate image interpretation. Efficient segmentation of ultrasound videos, however, is often complicated by low contrast, shadow effects, and complex “noise” statistics (unexplained variations). In addition, real-time applications such as navigation during operational surgery require efficient algorithms.
In an article published this month in the SIAM Journal on Imaging Sciences, authors Jiulong Liu, Xiaoqun Zhang, Bin Dong, Zuowei Shen, and Lixu Gu propose a video segmentation model to recognize ROI in ultrasounds. Read the rest of this entry »
Physical and biological models often have hundreds of inputs, many of which may have a negligible effect on a model’s response. Establishing parameters that can be fixed at nominal values without significantly affecting model outputs is often difficult; sometimes these parameters cannot be simply discerned by the outputs. Thus, verifying that a parameter is noninfluential is both computationally challenging and quite expensive. Read the rest of this entry »
Whether taking photos recreationally or professionally, photographers understandably want their snapshots to appear sharp and clear. Image clarity is dependent on exposure time, or the amount of time that a camera’s sensor is exposed to light while a photograph is being taken. During this period, the shutter opens and the camera counts the number of photons emitted by the subject. Read the rest of this entry »
SIAM is proud to be a member of the Conference Board of the Mathematical Sciences (CBMS). This year, the National Science Foundation has announced support for two NSF-CBMS Regional Research Conferences to be held in 2016, bringing the number of such conferences since the NSF-CBMS Regional Research Conference Series began in 1969 to 358!
These conferences are intended to stimulate interest and activity in mathematical research. Each five day conference features a distinguished lecturer who delivers ten lectures on a topic of important current research in one sharply focused area of the mathematical sciences. The lecturer subsequently prepares an expository monograph based upon these lectures, which is normally published as a part of a regional conference series. Depending upon the conference topic, the monograph may be published by SIAM, the American Mathematical Society, or jointly by the American Statistical Association and the Institute of Mathematical Statistics.
Support for about 30 participants is provided (though deadlines are quickly approaching) and the conference organizer invites both established researchers and interested newcomers, including postdoctoral fellows and graduate students, to attend. Learn more and get registered early.
Discrete Painleve Equations
Nalini Joshi, lecturer
May 16-20 at the University of Texas Rio Grande Valley
Baofeng Feng and Andras Balogh, organizers
Topological Data Analysis: Topology, Geometry, and Statistics
Sayan Mukherjee, lecturer
May 31- June 4 at the University of Texas at Austin
Lizhen Lin, Peter Mueller, and Rachel Ward, organizers
2017 Request for Proposals
Information about submitting proposals for future conferences may be found at Call for Proposals for the 2017 NSF-CBMS Regional Research Conferences. Institutions that are interested in increasing their research activity and profile are especially encouraged to apply. Proposals for conferences to be held in 2017 are due by April 29, 2016. Questions should be directed to
1529 18th St. NW
Washington DC 20036
Jupiter, which has a mass more than twice that of all the planets combined, continues to fascinate researchers. The planet is characterized most often by its powerful jet streams and Great Red Spot (GRS), the biggest and longest-lasting known atmospheric vortex. Although still images provide some insight into the features of Jupiter’s atmosphere, the atmosphere itself is unsteady and turbulent, and its features are time-dependent.
In a paper published this month in SIAM Review, authors Alireza Hadjighasem and George Haller use video footage to analyze Jupiter’s transport barriers and examine prior conclusions about Jupiter’s atmosphere. Read the rest of this entry »
Adaptive control techniques can help manage pests more effectively
As population growth, greater food consumption, competition for land use, and climate change pose challenges to world food production, managing loss of crop due to pests and weeds becomes increasingly important. While chemical pesticides offer effective means for control, potential loss of crop yield is still significant, as is cost. Global potential loss from pests has been estimated to be between 50% and 80% of yield based on crop type.
In a paper published last week in the SIAM Journal on Applied Mathematics, authors Chris Guiver et al propose adaptive control techniques to model pest dynamics and management as a control system. Read the rest of this entry »