Category: Graduate Programs
When a bug in Pentium processors was discovered that gave rise to incorrect solutions of scientific and mathematical calculations, the company was forced to take action. The result? Public outcry and the loss of $475 million worth of earnings.
It’s been almost two decades since the Pentium FDIV bug made headlines, but its discovery led to a new research thrust in computer science and engineering – one that Professor Sharad Malik, Chair of the Department of Electrical Engineering at Princeton University, knows quite well.
“It’s an instance of how real practical concerns have driven solutions to real, fundamental problems,” said Malik.
The incident brought the examination of Boolean Satisfiability or SAT, the challenge of determining if a logic formula will ever evaluate to true, to the forefront. In proving the correctness, this problem has a direct application to hardware and software and more specifically, avoiding costly bugs. SAT was already well known in computer science, but theoretical analysis deemed it to be too difficult to be applied in practice.
Malik is one of the nation’s experts on the topic, and his group has made several critical contributions to the field of SAT solvers that are now widely used in practice. On January 29, he visited Boston University to share his findings during the Department of Electrical & Computer Engineering Distinguished Lecture Series, which brings groundbreaking engineers to campus.
Currently, there is a strong motivation to discover useful SAT solvers thanks to all of the potential practical uses, such as in applications in artificial intelligence, circuit synthesis, and malware analysis.
“It’s already very widely used in hardware verification and we’re seeing an increasing use of the theory in software verification,” added Malik.
Though the SAT problem may be relatively unknown outside computer science and engineering, a very active community of researchers exists and can be found sharing their research and questions on the website, SAT Live!
Malik notes that the biggest change he’s noticed with SAT studies over the years is a revolution in how the topic is approached.
“There has been a significant shift from theoretical interest in SAT to how it can have a practical impact,” he said. What was once considered practically impossible due to its theoretical hardness is now within reach thanks to challenge-driven algorithmic and experimental research.
Malik’s talk was the first in the three-part Spring 2014 Distinguished Lecture Series. The next talk features Professor C. V. Hollot of University of Massachusetts, Amherst, who will speak on the topic, “Regulation of Cell Populations in Individuals Using Feedback-Based Drug-Dosing Protocols.” Hear him on March 5, 2014, at 4 p.m. in Room 211 of the Photonics Center, located at 8 Saint Mary’s St.
-Rachel Harrington (email@example.com)
After the Boston Marathon bombings last year, it took authorities just three days to sift through an abundance of footage and find their suspects – light speed compared to the weeks it took to find those responsible for the London bombings in 2005.
Still, can this happen faster? Professor Venkatesh Saligrama (ECE, SE) thinks so, and he’s working to making that vision a reality.
The Office of Naval Research awarded him $900K for his project, Video Search and Retrieval, which will focus on developing a visual search system. Think Google but for security videos.
“Our initial idea was to develop a system that could annotate web videos,” said Saligrama, who collaborated with Pierre-Marc Jodoin at the University of Sherbrooke on early stages of this research. “That project turned out to be extremely challenging so we started to focus on surveillance videos, where the footage is obtained in a controlled environment.”
Manually searching large archives of footage can be both time-consuming and monotonous. Saligrama and Ph.D. students, Greg Castanon (ECE) and Yuting Chen (SE), are now working closely with the U.S. Naval Research Laboratory to help change this.
Chen said she is looking forward to working on this project with Saligrama, who she first encountered while conducting her own research.
“I spent almost a year and a half working on an idea that employs correlating motion clues to calibrating camera networks,” she said. “When I came to BU Systems Engineering and browsed the research papers, I found the exact idea implemented by Venkatesh’s group. I was surprised and just a little bit bitter.”
From there, she knew that she wanted to study with Saligrama.
“He is an experienced researcher and just as passionate and curious as a young freshman,” she said. “I find that one sentence from him can help me through a problem that’s been troubling me for weeks.”
Chen, Castanon and Saligrama hope that together, they can make the process of searching through security footage more automated and responsive to user query video searches.
“Currently, for many YouTube videos, there are textual meta-tags that are used in the search process,” Saligrama explained. “For surveillance videos, we do not often have this so our searches need to be based purely on visual features and patterns.”
One of the challenges in video search is that activity patterns can be highly inconsistent and can occur for unpredictable amounts of time.
“Unlike image search though, videos have some temporal patterns we can exploit,” said Saligrama.
In the future, Saligrama hopes that the research will not only improve security but improve medical database searches as well.
For more information about the project, visit our Research Spotlight page.
-Rachel Harrington (firstname.lastname@example.org)
Features tour of ENG’s new design, manufacturing studio
The Engineering Product Innovation Center (EPIC) hadn’t yet opened for its inaugural semester, and it already had a wait list of students eager to register for classes in the sleek, glass-fronted Commonwealth Avenue building that not too long ago was the Guitar Center. That bodes well for the College of Engineering and the University officials and corporate sponsors who made the new facility possible.
ENG will host EPIC’s ribbon-cutting ceremony this Thursday, January 23. Among those present will be President Robert A. Brown, ENG Dean Kenneth Lutchen, local dignitaries, and key corporate partners, including representatives from principal industry sponsors GE Aviation, Procter & Gamble, PTC, and Schlumberger.
Lutchen, who is also an ENG professor of biomedical engineering, says that EPIC’s opening “now begins the opportunity for us to transform our engineering education at the undergraduate level to really create a much more powerfully enabled graduate who understands the process of designing products from conception to deployment.”
Those skills are particularly important, and valuable, now that manufacturing is making a comeback in the United States. US manufacturers have added at least 500,000 new workers since the end of 2009, energy costs have dropped, and labor costs in competing countries such as China and India have been inching upward.
Companies like Apple and GE are bringing high-tech facilities back home from overseas. While a positive development, “the problem is now there aren’t enough engineers trained in highly technological methods,” says Bruce Jordan, ENG assistant dean of development and alumni relations.
EPIC could help fill that void. “We’re hoping to set a standard for the training of engineers for the future manufacturing economy in this country,” says EPIC director Gerry Fine, an ENG professor of the practice.
Funded through the University, ENG alumni and friends, and regional industry, EPIC’s 20,000-square-foot space houses a computer-aided design (CAD) studio, demonstration areas, fabrication facilities, materials testing, and project management software available to engineering students in all specialties — from computer and electrical engineering to biomedical engineering and nanotechnology. The facility has a flexible design and offers students supply chain management software, 3-D printers, robotics, laser processing, and around-the-clock digital access to the studio’s online resources.
A representative from each principal industry sponsor, GE Aviation, Procter & Gamble, PTC, and Schlumberger, will sit on EPIC’s Industrial Advisory Board, whose primary function will be to offer suggestions on how the ENG undergraduate curriculum might be redesigned to better prepare students for employment in the years ahead.
“We want to create as many options for our graduating students as possible,” Fine says. “By teaching them some of the things that regional industry wants, we think we’re giving our students more options. And we’re making our students more desirable to potential employers.”
Representatives from the principal sponsors will also participate in guest lectures and provide case studies and projects, and the companies will offer internship and employment opportunities to qualified students.
While other universities have manufacturing-oriented centers, most focus on basic research, but EPIC allows engineering students to put theory into practice by converting their ideas into products that could one day benefit society.
Fine has given tours of the facility to at least five teams from other universities since June. “We’re not aware of anyone who’s invested in this scale and made this commitment to undergraduate education,” he says.
“When I first heard from Dean Lutchen about the idea of EPIC, I was thrilled,” says Michael Campbell (ENG ’94), executive vice president of PTC’s CAD segment, who will serve on EPIC’s advisory board. “I always felt that my engineering education lacked that real-world perspective, that real-world exposure to the challenges, processes, and complexities of collaboration and the sophistication of tools. Now we have a chance to share all of that with students.”
J. David Rowatt, research director and technical advisor at Schlumberger, echoes that sentiment. “There were so many things I didn’t learn in school that I picked up on the job,” he says. “Some of these are clearly being addressed by what EPIC is trying to do,” which is exposing students to the entire engineering process — from conception and manufacturing to working on deadlines and understanding resource constraints.
Greg Morris, strategy and business development leader for additive manufacturing with GE Aviation, says this generation of students grew up in a world where computers and software were second nature, but tinkering under the hood of a car was not. EPIC will provide engineering students with the hands-on experience that gives them an advantage in the marketplace. “I can’t tell you how much that resonates with an employer,” he says.
Both BU and its partners see EPIC as a win-win. ENG faculty and students will benefit from a revamped curriculum and access to global leaders in innovation and manufacturing, while industry partners will interact with the University’s deep bench of cutting-edge researchers and get exposure to a new crop of engineers.
“If we tap into EPIC,” says Bruno De Weer, the vice president of global engineering at Procter & Gamble, “we can find ourselves connected with another hub of innovation that brings the very best.”
The EPIC ribbon-cutting ceremony will be held at 4:30 p.m. on Thursday, January 23, at 750 Commonwealth Ave., followed by a reception and tours for those invited. The event is not open to the public.
-Leslie Friday, BU Today
Boston University students have big ideas – whether they’re aiming to prevent cyber attacks or using GPS data to improve cattle herding. As good as their work is though, they don’t always know the best way to present their research.
Ph.D. students, Yasaman Khazaeni, Greg Castanon, and Jing Wang, initially came up with the idea for the event last semester and hoped it would give their classmates a chance to practice speaking in front of a large audience.
“One of the main issues we have as students becomes clear at conferences,” said Khazaeni. “We’ve done great research but don’t present it well.”
Often times, she added, engineering students come from international backgrounds and don’t have enough confidence to present in English.
“By speaking in front of a friendly audience, as opposed to a conference where you’d know few people in the audience, your classmates and professors can offer feedback and really help you smooth out your final presentation,” said Khazaeni.
Khazaeni, who helped choose 14 students to present out of a pool of 23 applicants, said that the event also allowed CISE students to learn from classmates and discover more about the projects they’ve been working on.
Among those she learned from were Ph.D. students, Morteza Hashemi and Delaram Motamedvaziri, who took home the Best CISE Presenter awards.
Hashemi, who is advised by Professor Ari Trachtenberg (ECE, SE), spoke about his project, Coded Data Sharing in Intra-Car Wireless Sensor Networks. He has been working with Trachtenberg, Professor David Starobinski (ECE, SE), Ph.D. student, Wei Si, and General Motors Research to determine if using wireless sensor networks (WSN) might allow for a greener way to construct tomorrow’s vehicles. The work previously won the Center for Reliable Information Systems and Cybersecurity Award as well as the Provost’s Award at Scholars Day last year.
Advised by Professor Venkatesh Saligrama (ECE, SE), Motamedvaziri spoke about her work, “Poisson Statistics and the Future of Internet Marketing.”
“The effectiveness of search engine marketing is dropping while the power of social media marketing is rising,” she explained. “Mathematics would suggest that social media is now the better advertising strategy.”
She said that though her research focused on total hits advertisements received, she’d like to expand her work in the future by looking at data concerning how long a person stayed on a website.
“Ultimately, we’re more interested in seeing transactions occur as opposed to clicks,” said Motamedvaziri.
Also honored at a reception at the BU Castle following the presentations were Setareh Ariafar, the Most Attentive CISE Student, and Professor David Castañón (ECE, SE), awarded for his contributions to CISE. Because 20 students attended all fourteen presentations, the most attentive of them was chosen by raffle.
In case any students left the workshop having doubts about their speaking skills, Professor Christos Cassandras (ECE, SE) closed the day by offering some advice, including “never overestimate the intelligence of your audience” and “the maximum pieces of information that should appear on a slide is two.”
“Giving a good talk is a difficult thing,” he said. “It’s as much of an art as a science.”
-Rachel Harrington (email@example.com)
Goldberg, Wong named to coordinate teaching, recruitment
It’s a fitting acronym: STEM is the basis for budding careers, for the growing of cutting-edge research, and for increased competence across a range of disciplines. While Boston University has long shown a strong commitment to education in STEM fields — science, technology, engineering, and mathematics — it has recently launched an initiative to improve that commitment by boosting interdisciplinary cooperation, recruiting more students in underrepresented populations, and arming the University with even more of a competitive edge in seeking outside funding.
Jean Morrison, University provost and chief academic officer, recently named two BU faculty members to take STEM to the next level. Bennett Goldberg, a College of Arts & Sciences professor of physics and a College of Engineering professor of electrical and computer engineering and of biomedical engineering, has been appointed director of BU’s STEM Education Initiatives. Joyce Y. Wong, an ENG professor of biomedical engineering and of materials science and engineering, has been named director of a new University effort to advance women in STEM fields.
Goldberg will be responsible for oversight and coordination of efforts to “increase effectiveness of instruction” in STEM subjects, says Morrison in announcing the appointment. “A world-class scientist, innovator, and teacher, who has devoted his career to impactful interdisciplinary scholarship, Professor Goldberg is exceptionally equipped for this responsibility,” she says. The new post includes four major areas of oversight: leading an effort to “articulate the aspirations” of BU faculty for undergraduate STEM education; working with schools and colleges and the Center for Excellence and Innovation in Teaching to advance the “sharing of best practices”; working to boost recruitment of students, including women and minorities, underrepresented in STEM programs; and directing the development, writing, and submission of grants supporting STEM education at the University.
“STEM education at BU has a fair amount of innovation, but we don’t have a really coordinated effort or strategic plan,” says Goldberg. “If you look at what’s happening in higher education in the United States, there are a lot of pressures, and our model for the future must include high-engagement learning — moving away from the traditional talking head at the front of the class.” In STEM education in particular, the talking head model reaches “a very small fraction of our students,” he says.
STEM education at BU is already embracing this move away from the traditional lecture model, but Goldberg will coordinate the establishment of more interactive learning studios, more peer learning, more small seminars like those used in some engineering courses, and more roundtable teaching. “My job is really to figure out what kind of support is necessary and how we can create a collective vision,” he says. “It’s planning, it’s discussing, it’s developing, and it’s implementing.”
Goldberg, who was named BU’s 2013 United Methodist Scholar-Teacher of the Year, has long held an active interest in improving education in math and the sciences. Director of the Center for Nanoscience and Nanobiotechnology since 2004, he earned a bachelor’s from Harvard University and a master’s and a doctorate from Brown University. Of Goldberg’s work cultivating clean energy sources, developing new drug delivery systems, and diagnostic methods, Morrison says that he “has committed himself to breaking boundaries, working across fields of scientific research in a way that pushes the limits of our capabilities.”
Wong is “uniquely positioned to help BU emerge as a leader in addressing the underrepresentation of women” in STEM fields, according to Morrison. She notes that while BU attracts outstanding female students and faculty in these fields, “there is more work to be done both in recruitment and retention and in our endeavors to support their success.” Wong’s undergraduate and doctoral degrees are from the Massachusetts Institute of Technology. Her research focuses on the development of biological materials that could aid in detecting cancer and cardiovascular disease.
“I look forward to engaging all members of the BU community and to reaching out to the many people on campus who are running excellent programs at all levels, precollege, undergraduate, graduate, postdoctoral, and faculty, to advance STEM in an equitable manner,” says Wong.
-Susan Seligson, BU Today
Telecommunications companies – those that allow us to talk on the phone, communicate over the Internet and watch cable television – used to operate under the notion that there was an infinite amount of fiber bandwidth available to transmit these signals. Then we moved into the Y2K era.
“There was a big explosion of data around the year 2000,” said Larry A. Coldren, the Fred Kavli Professor of Optoelectronics and Sensors at the University of California, Santa Barbara. “Computers were also getting faster and faster at this time and the demand for bandwidth was rising quickly.”
Coldren and his team had started looking at photonic integrated circuits (PICs), devices that allow signals to travel on optical waves on semiconductor chips, back in the 1980s and discovered that they could viably be produced much like analogous electronic integrated circuits (ICs) that generally use electrical wires for transferring data.
Last month, he spoke about his research during Boston University’s Electrical & Computer Engineering Distinguished Lecture Series. He suggested that PICs could be the key component in the future of telecommunications.
Just a couple of decades ago, wavelength-division multiplexing (WDM) was introduced to meet the demand for more fiber bandwidth. This method allowed a number of signals to be simultaneously transferred on a single optical fiber. However, at the terminals where the WDM channels must be either combined or separated, the optical and electronic equipment became more and more complex as the channel count and signal speed increased. That’s where Coldren’s research comes into play.
“PICs have the potential of improved performance, reliability and cost while also reducing the size, weight and power of the equipment,” said Coldren.
PICs for various applications have been made using indium phosphide, silica on silicon, polymer technologies, and silicon photonics. Electronic ICs, however, usually use silicon as a dominant ingredient. Coldren’s team currently focuses on a monolithic indium phosphide integration platform.
“Ultimately, we may find that the best results will come from a hybrid solution using more than one of these materials,” said Coldren.
Today, PICs are widely deployed commercially and outperform many discrete device approaches, but Coldren is optimistic that they can work even better in the future and hopefully result in more environmentally friendly supercomputers and data centers.
“Our efforts have always been focused on making PICs very efficient and very fast,” said Coldren. “Now we need to look at how they can be used to create more green data centers.”
Assistant Professor Jonathan Klamkin (ECE), who introduced Coldren at the lecture, previously had an opportunity to study with Coldren while earning his Ph.D. at UC Santa Barbara.
“I benefitted immensely from his guidance and even use his books in my class here,” Klamkin said. “It’s a pleasure having him on our campus.”
Prior to teaching, Coldren worked at Bell Labs, where he studied surface-acoustic-wave signal processing devices and tunable coupled-cavity lasers. He continued his work at UC Santa Barbara, where he has developed more widely-tunable DBR lasers and efficient, high-speed vertical-cavity-surface-emitting lasers (VCSELs) in addition to his PIC research.
Coldren is a member of the National Academy of Engineering and a Fellow of the Institute of Electrical and Electronics Engineers (IEEE), the Optical Society (OSA) and the Institution of Electrical Engineers (IEE).
Coldren’s talk was the third in the three-part Fall 2013 Distinguished Lecture Series. The seminars will resume in Spring 2014.
-Rachel Harrington (firstname.lastname@example.org)
Over the last few weeks, nearly 20 million Americans tried accessing a broken United States health care site that couldn’t handle the traffic, among other problems. And even if you weren’t one of the many applying for health coverage, you’ve probably experienced network congestion at some point.
Typically, network congestion occurs if a link or node is carrying too much data; as a result, the quality of service drops. The most severe form of communication disruption is deadlocks. A deadlock happens when several messages mutually block each other so that their delivery is not just delayed but stopped permanently.
“This is a long-standing problem, which is practically important and theoretically challenging,” said Distinguished Professor Lev Levitin (ECE, SE). “It has been attracting the efforts of many researchers for decades.”
Professors Levitin and Mark Karpovsky (ECE) have been working with their students on this problem for several years, developing new algorithms, specifically turn prohibition algorithms, to help direct data and essentially prevent information from being stuck in a deadlock as it travels through communication networks. This work covered a lot of ground by establishing lower and upper bounds for an optimal solution, outlining their discovery of a new class of algorithms, and developing a few algorithms that could actually solve the initial optimization problem.
The last advance on this project was achieved this year by Levitin and his team – ECE alum, Ye Wu (MEng ’13), and Visiting Scholar, Mehmet Mustafa. They have been working on developing new algorithms, specifically turn prohibition algorithms, to help direct data and essentially prevent information from being stuck in a deadlock as it travels through communication networks.
“Without changing the topology of existing networks, we managed to improve saturation points so that congestion is less likely to happen and latency is reduced which means lower waiting time for users,” said Wu.
The team recently presented their work at OPNETWORK 2013, a conference that focused on advancing the state of application and network performance management. Impressed by their research, “A Study of Modified Turn Prohibition Algorithms for Deadlock Prevention in Networks,” the judges awarded them Best Technical Paper.
“Computer experiments, executed earlier and in the latest work by Ye Wu and other students under the guidance of Dr. Mustafa, clearly showed the superior performance of our algorithms versus different algorithms suggested by other research groups,” said Levitin. He went on to add that the majority of publications in the field are on ad hoc algorithms as opposed to the “tree-free” algorithms he and his team explored.
The work gave Wu a chance to travel to Washington, D.C., and deliver the presentation at the Ronald Reagan Building and International Trade Center.
“I met some really nice students and professors from different countries who were happy to talk about their research,” said Wu. “The audience, I think, was also smart enough to understand the key points of our project and asked really good questions.”
Now a Boston University graduate, Wu looks back at his professor fondly, describing Levitin as open-minded, even when his student was questioning his own theories.
“Professor Levitin is the best professor I’ve ever known,” said Wu. “Even when we had no idea how to begin a project, he’d point us in the right direction.”
-Rachel Harrington (email@example.com)
NSF Research Program Helps ENG Vets Shape Careers
US military personnel return from active duty with highly marketable knowledge and skills, but many find it difficult to quickly parlay their experience into well-paying jobs. To help rectify the situation, the National Science Foundation (NSF) funds the Veteran’s Research Supplement (VRS) program, which allows veterans at selected colleges and universities to participate in industrially relevant research in science, technology, engineering, and mathematics (STEM) — fields in which job openings far outpace the supply of qualified US applicants.
Since the inception of VRS in 2011, the College of Engineering’s NSF Industry/University Collaborative Research Center for Biophotonic Sensors & Systems has welcomed the opportunity to engage veterans in research through this program.
“Vets come to us with an unusually strong work ethic and high confidence but often lack the experience to be comfortable in taking on a big research project,” said BU Photonics Center Director and Professor Thomas Bifano (ME, MSE). “VRS gives them the opportunity to take on such projects and pursue careers in research, which is the main engine of our economy.”
So far two veterans have thrived in faculty-supervised summer projects funded by VRS, emerging not only with new research skills but also a more well-defined career path.
Cliff Chan: From Technician to Engineer
Cliff Chan, who deployed four times in the Middle East and Southeast Asia as an Air Force Guidance and Control Specialist, came to BU seeking to take his skillset to the next level. With a B.S. in mathematics and computer science from the University of California, San Diego, two years developing software for an electronic health records company, and four years maintaining aircraft control systems for the Air Force under his belt, Chan aspired to learn how to design the kinds of technologies he came across during his military service.
To transform himself from a technician to an engineer, he sought a way to earn a master’s degree in electrical engineering in a reasonable timeframe without having to start from scratch, and he found it in the College of Engineering’s Late Entry Accelerated Program (LEAP). Like all LEAP students, Chan spent his first year taking undergraduate engineering courses to get up to speed, but got his first taste of engineering design the following summer (2011), thanks to the VRS program. Working for three months in Professor Jerome Mertz’s (BME) Biomicroscopy Lab within BU’s Center for Biophotonic Sensors and Systems, he developed software that enables microscopes to provide high-contrast images of biological samples in real time.
“The project was a real transition for me, as I had to solve a problem by first figuring out what I needed to learn, and then how to apply it,” recalled Chan, who was used to getting more explicit instructions in the Air Force and had never worked in a research lab. “It opened up my eyes to another world.”
Subsequently hired to work full-time in the Biomicroscopy Lab while completing his Master of Engineering in electrical engineering, Chan has continued to advance microscopy techniques aimed at improving medical diagnostic imaging. The experience has led him to consider working in research and development for defense and other industries, conducting experiments and designing devices with real-world applications.
It has also prepared him to work through the inevitable unexpected challenges that arise in advancing new technologies.
“What I like about Cliff is that he’s undaunted,” said Mertz. “He wants to learn everything that’s out there to tackle his work. The problems we faced were much more complex than I had anticipated, but Cliff’s efforts definitely kept us on track, and kept us progressing.”
Chris Stockbridge: From Defusing Roadside Bombs to Protecting Future Soldiers
Chris Stockbridge returned to civilian life after five years as an officer and combat engineer in the Army that included two tours of duty in Iraq. During each deployment he came to appreciate the engineering behind technologies used to protect soldiers, including devices used to search for and destroy roadside bombs. Equipped with those experiences and a B.S. in mechanical engineering from the US Military Academy at West Point, he applied to the PhD program in mechanical engineering at BU with the goal of working as a civilian engineer at a national military research lab.
“I came to BU to study micro-electro-mechanical systems (MEMS), particularly those which could be of great value in military applications, and because I knew that the Photonics Center has a strong relationship with the US Army Research Laboratory,” said Stockbridge.
Supported last summer by the VRS program to serve as the lead student in an NSF-funded project in Bifano’s Precision Optics Research Lab, he began fabricating MEMS for a new deformable mirror design for use in the Keck and other very large telescopes. Aimed at supplying the telescopes with mirrors that have more pixels for finer imaging control, his work could enable astronomers to make observations that shed light on the origin of the universe and the existence of life on extra-solar planets.
“The primary benefit to me from this project was spending more time doing hands-on MEMS fabrication work,” said Stockbridge, who had already spent two years working on the design of deformable mirrors in Bifano’s lab. “While I would prefer to work more in design after graduation, the hands-on skills are important for getting an appreciation of each process step that goes into building a MEMS mirror.”
As he has cultivated those skills, Stockbridge has proven to be an invaluable asset in Bifano’s lab.
“Chris is a consummate engineer who seems to thrive on tackling problems that are both thorny and hard, and I can see in his work the experience and training that he gained while serving in the Army,” said Bifano. “He is a natural collaborator, and all of the other students in my lab and in the labs of my close colleagues have come to rely on him for his strong sense of mechanical design and for his eagerness to help those around him. Chris will make a great professional engineer.”
-Rachel Harrington (firstname.lastname@example.org)
Each day, we find ourselves sharing our personal information across the internet – whether it’s to pay a bill or buy a gift on Amazon.
As we send more of our data through these channels, there is a growing concern about privacy. Earlier this month, a breach at Adobe, for example, impacted more than 38 million users. Cases like this are not uncommon and as a result, cyber security has become a major area of research for electrical and computer engineers.
Last week, Professor George J. Pappas, the Chair of the Department of Electrical and Systems Engineering at the University of Pennsylvania, visited Boston University and shared his own work on the topic.
Pappas is looking at how differential privacy, a method that aims to maximize the accuracy of information extracted from databases while also minimizing the chance of records being identified, can be applied to systems like smart grids and intelligent transportation systems.
“Privacy breaches are generally due to side information that a company collects,” Pappas explained. He believes that by using a differentially private mechanism to transfer information, it’ll be possible to hide secure data.
“You’re trying to hide in the noise and make it hard to know who’s who,” he said.
Pappas believes that one of the greatest challenges is figuring out how to give companies like Google and eBay the information they need without the sensitive data they don’t.
An advantage of differential privacy, he said, is that once you indicate a particular segment of information is private, it stays private even after the data is sent to another system. Pappas believes that by adding noise during the streaming process, secure information can be blocked. The trick is figuring out how much noise should be added.
Pappas is a Fellow of IEEE and has received several awards including the Antonio Ruberti Young Research Prize, the George S. Axelby Award, and the National Science Foundation PECASE. In addition to differential privacy, his research focuses on control theory and, in particular, hybrid systems, embedded systems, hierarchical and distributed control systems, with application to unmanned aerial vehicles, distributed robotics, green buildings, and biomolecular networks.
Pappas’s talk was the second in the three-part Fall 2013 Distinguished Lecture Series. The next talk will feature Professor Larry A. Coldren, University of California, Santa Barbara, who will speak on the topic, “Photonic Integrated Circuits as Key Enablers for Coherent Sensor and Communication Systems.” Hear him on Wednesday, November 20, at 4 p.m. in PHO 211.
-Rachel Harrington (email@example.com)
New Laser Technique Boosts Accuracy of DNA Sequencing Method
Low-cost, ultra-fast DNA sequencing would revolutionize healthcare and biomedical research, sparking major advances in drug development, preventative medicine and personalized medicine. By gaining access to the entire sequence of your genome, a physician could determine the probability that you’ll develop a specific genetic disease or tolerate selected medications. In pursuit of that goal, Associate Professor Amit Meller (BME, MSE) has spent much of the past decade spearheading a method that uses solid state nanopores — two-to-five-nanometer-wide holes in silicon chips that read DNA strands as they pass through — to optically sequence the four nucleotides (A, C, G, T) encoding each DNA molecule.
Now Meller and a team of researchers at Boston University — Professor Theodore Moustakas (ECE, MSE) and research assistants Nicolas Di Fiori (Physics, PhD ’13) and Allison Squires (BME, PhD ’14) — and Technion-Israel Institute of Technology — have discovered a simple way to improve the sensitivity, accuracy and speed of the method, making it an even more viable option for DNA sequencing or characterization of small proteins.
In the November 3 online edition of Nature Nanotechnology, the team demonstrated that focusing a low-power, commercially available green laser on a nanopore increases current near walls of the pore, which is immersed in salt water. As the current increases, it sweeps the salt water along with it in the opposite direction of incoming samples. The onrushing water, in turn, acts as a brake, slowing down the passage of DNA through the pore. As a result, nanoscale sensors in the pore can get a higher-resolution read of each nucleotide as it crosses the pore, and identify small proteins in their native state that could not previously be detected.
“The light-induced phenomenon that we describe in this paper can be used to switch on and off the ‘brakes’ acting on individual biopolymers, such as DNA or proteins sliding through the nanopores, in real time,” Meller explained. “This critically enhances the sensing resolution of solid-state nanopores and can be easily integrated in future nanopore-based DNA sequencing and protein detection technologies.”
Slowing down DNA is essential to DNA or RNA sequencing with nanopores, so that nanoscale sensors, like sports referees, can make the right call on what’s passing through.
“The goal is to hold a base pair of DNA nucleotides in the nanopore’s sensing volume long enough to ‘call the base’ (i.e, determine if it’s an A, C, G or T),” said Squires, who fabricated nanopores and ran experiments in the study. “The signal needs to be sufficiently different for each base for sensors in the nanopore to make the call. If the sample proceeds through the sensing volume too quickly, it’s hard for the sensors to interpret the signal and make the right call.”
Other methods designed to slow down DNA in nanopores change the sensing properties of the pore, making it more difficult to ensure accuracy of detected base pairs. Shining laser light on the nanopore alters only the local surface charge, an effect that’s completely reversible within milliseconds by switching the laser off.
As an added bonus, the researchers found that the sudden increase in surface charge and resulting flow of water reliably unblocks clogged nanopores, which can take a long time to clean, significantly extending their lifetime.
Meller and his team characterized the amount of increase in current under varying illumination in many different-sized nanopores. They next aim to explore in greater detail the mechanism underlying the increase in surface current when the green laser is applied to a nanopore, information that could lead to even more sensitivity and accuracy in DNA sequencing.
The research is funded by a $4.2 million grant from the National Institute of Health’s National Human Genome Research Institute under its “Revolutionary Sequencing Technology Development — $1,000 Genome” program, which seeks to reduce the cost of sequencing a human genome to $1,000.