EE Graduate Seminar

High Power Mid-Infrared Quantum Cascade Laser
Arrays for Standoff Photoacoustic Chemical Detection

Xing Chen, PhD (EE) Student
Computer Science and Electrical Engineering, UMBC

11:30am-12:45pm, Friday, 30 March 2012, ITE 237

Quantum cascade lasers (QCLs) are compact, powerful, mid-infrared, Semiconductor laser sources. High power QCLs are very important to infrared counter measures (IRCM) and standoff chemical detection applications, as well as others. The performance of such systems critically depend on the amount of power that QCLs can produce. One way to achieve high power operation is to use multi-emitter phase-locked laser arrays.

The first part of the seminar presents the issues and challenges to design, fabricate, and characterize multi-emitter phase-locked QCL arrays for achieving high power operation. The second part of the seminar discusses using high power mid-infrared QCLs to perform standoff photoacoustic (PA) chemical detection. The PA effect is a photo-matter effect involving generation and detection of an acoustic signal when a gas sample absorbs electromagnetic energy (particularly of light).

In recent years, with the help of the development of mid-infrared QCLs, significant progress has been made in their use for PA chemical detection, and sensitivity has been improved significantly. Our theoretical and experimental studies of standoff photoacoustic chemical detection, using QCLs as the laser source, will be presented.

Xing Chen received the BS degree in Opto-Electronics Engineering from Huazhong University of Science and Technology in 2007, and the MSEE degree from UMBC in 2009. He is currently a PhD (EE) candidate at UMBC. Mr. Chen's research interest includes design and fabrication of high power mid-infrared phase-locked QCL arrays and application to standoff photoacoustic chemical detection.

Host: Prof. Joel M. Morris

The English Department’s Christopher Corbett will be featured Saturday, April 14 at the CityLit Project at Baltimore’s Enoch Pratt Free Library in a panel discussion on the art of writing biography. Corbett is the author of Orphans Preferred: The Twisted Truth and Lasting Legend of the Pony Express (Random House/Broadway Books) and The Poker Bride: The First Chinese in the Wild West (Atlantic Monthly).

http://www.citylitproject.org/index.cfm?page=news&newsid=113

Maryland DNR, Aquatic Resource Education Department is excited to participate in the Chesapeake Bay Trust’s Chesapeake Conservation Corps, in which an opportunity exists for a stipend Volunteer to spend a one-year term of service working with the department. The intern would support  programs for schools such as Raising Horseshoe Crabs in the Classroom, Maryland Envirothon, Green Eggs and Sand curriculum; developing new activities and updating current programs to incorporate climate change and invasive species data;  outreach events such as wade ins, the Maryland Seafood Festival, and professional conferences; and other educational opportunities.  In addition, the Volunteer will participate in activities with the full Corps.  The purpose of the Corps is 1) to enable stipend volunteers to work with host organizations and communities throughout Maryland to implement on-the-ground restoration and energy conservation projects, and 2) to provide leadership and training opportunities for young adults pursuing environmental and conservation careers. 

Interested applicants should apply directly through the Chesapeake Bay Trust by following instructions at www.cbtrust.org/chesapeakeconservationcorps; however, they are encouraged to contact us as well at 410-260-8775 or by email at sepperson@dnr.state.md.us.  The application deadline is May 14, 2012, with the one-year service term to begin in late August, 2012.

From the White House

Apply to be a Fall 2012 White House Intern

We are reaching out to remind you that the application for the Fall 2012 program is now open. If you or anyone else you know is interested in the program, we encourage you to forward this information and apply by April 1, 2012 at: http://www.whitehouse.gov/about/internships/apply/application

White House Interns have the chance to work with government officials in offices such as the Office of the First Lady, the Office of the Chief of Staff, the Office of Public Engagement and Intergovernmental Affairs, the National Economic Council and the Domestic Policy Council. Assignments vary dependent on an intern’s office, but interns conduct research, attend meetings with officials, write memos and requests, participate in speaker series’ with senior staff members, engage in service projects, and staff and plan events. By dedicating their time, talents, energy and service, interns become part of the White House team and work to improve the community and the nation.

Ph.D. Defense

Multivariate Time Series Analysis
of Physiological and Clinical Data

Patti Ordóñez Rozo

1:00pm Thursday, 29 March 29 2012, ITE 325b UMBC

The complexity and volume of collected medical data is greater now than at any point in the history of medicine. Medical providers are expected to examine large volumes of data and identify correlations among parameters based on their own clinical experience to detect significant medical events or conditions. The information overload that providers may face may hinder the diagnostic process. Most existing visualizations of the data to assist the provider in analyzing the information consist of a table or plot of values for a particular parameter as a function of time. Automated techniques for discovering these correlations not only may assist the provider in making a diagnosis but may help to identify hidden patterns within the data associated with specific medical conditions or events. Current visualization and machine learning techniques show promise for extracting this information.

This dissertation presents three novel representations and two visualizations to assist in the analysis of multivariate time series data. It focuses on physiological and clinical data, in particular, because this type of data captures the complexity of a human being, and thus, the multivariate time series in this type of data are more interdependent and synchronized than most. The three representations are the Multivariate Time Series Amalgam (MTSA), the Stacked Bags-of-Patterns (Stacked BoP), and the Multivariate Bag-of-Patterns (Multivariate BoP). Each provides an integrated, multivariate approach for representing multivariate time series data. An evaluation of the latter two techniques against two techniques that use univariate techniques of multiple variables, Ensemble Voting with Bag-of-Patterns and Multivariate Piecewise Dynamic Time Warping in five diverse datasets yields interesting insights into the classification of multivariate time series.

The MTSA representation is the foundation for two visualizations – the MTSA Visualization and the Fixed Dual MTSA Visualization. These animated visualizations capture the rate of change of provider-selected parameters and the relationships among them. While both visualizations were created for the medical domain, they generalize to domains where multiple variables measure the state of an entity as a function of time. An evaluation of the Fixed Dual MTSA Visualization was carried out with 23 pediatric residents at Johns Hopkins University School of Medicine. The results indicate that the visualization merits further investigation for use as a diagnostic tool.

Committee

• Dr. Tim Oates (co-chair)
• Dr. Marie desJardins (co-chair)
• Dr. Anupam Joshi
• Dr. Jim Fackler, JHMI
• Dr. Christoph U. Lehmann, JHMI

With the passing of today’s 5:00 p.m. deadline, the Election Board now has a preliminary list of candidates. Please note that this list is subject to verification by the Election Board and candidate eligibility checks. Please also note that this is not necessarily the order in which candidates’ names will appear on the ballot, as the order of names will be randomized prior to the actual election.

The SGA Student Vote website will be under construction for the next few days, but it will return with information about all the candidates running for SGA elected positions–be sure to use this as a resource as you follow the campaign. The SGA Election will take place Monday, April 23 through Wednesday, April 25.

And without further delay, here is the unofficial list:

President (3 candidates)

Nana Asare (running mate = David Stonko)
Nathaniel Buechler (running mate = Drew Kelly)
Kayleswari Ramu (running mate = Kian Larijani)

Executive Vice President (3 candidates)

Drew Kelly (running mate = Nathaniel Buechler)
Kian Larijani (running mate = Kayleswari Ramu)
David Stonko (running mate = Nana Asare)

Vice President for Student Organizations (1 candidate)

Michelle Kuah

Treasurer (2 candidates)

Chisom Ebinama
Samantha Spehr

Finance Board Representative – 5 positions (6 candidates)

Joshua Day
Macy Bokhari
Mani Gupta
Damani Lewis
Mark Crenshaw
Tavien Kimbrough

Senator – 11 positions (13 candidates)

Amaedi Etukudo
Valerie Parks
Jacqueline Scott
Tyler McCafferty
Max Barnhart
Benjamin Garmoe
Hannah Khan
Morgan Russo
Yasmin Wands
Ganesh Mysore
Fabian Omenankiti
Rebecca Behnke
Angela Mensah

The GOP presidential primary is drawing more attention in Maryland than usual, AP reports, given the protracted fight for the nomination among the top candidates. Anticipating a low primary election turn-out among Maryland Republicans, which already comprise a relatively small group, former Gov. Ehrlich suggests the results are “difficult to predict.”

Don Norris, UMBC professor and chair of public policy, disagrees. “I think it’s going to go for Romney,” he says, “because even the base in Maryland is not as conservative of a base as…some other states.”