Category Archives: Internet

Computers that explain themselves

Machines that predict the future, robots that patch wounds, and wireless emotion-detectors are just a few of the exciting projects that came out of MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) this year. Here’s a sampling of 16 highlights from 2016 that span the many computer science disciplines that make up CSAIL.

Robots for exploring Mars — and your stomach

  • A team led by CSAIL director Daniela Rus developed an ingestible origami robot that unfolds in the stomach to patch wounds and remove swallowed batteries.
  • Researchers are working on NASA’s humanoid robot, “Valkyrie,” who will be programmed for trips into outer space and to autonomously perform tasks.
  • A 3-D printed robot was made of both solids and liquids and printed in one single step, with no assembly required.

Keeping data safe and secure

  • CSAIL hosted a cyber summit that convened members of academia, industry, and government, including featured speakers Admiral Michael Rogers, director of the National Security Agency; and Andrew McCabe, deputy director of the Federal Bureau of Investigation.
  • Researchers came up with a system for staying anonymous online that uses less bandwidth to transfer large files between anonymous users.
  • A deep-learning system called AI2 was shown to be able to predict 85 percent of cyberattacks with the help of some human input.

Advancements in computer vision

  • A new imaging technique called Interactive Dynamic Video lets you reach in and “touch” objects in videos using a normal camera.
  • Researchers from CSAIL and Israel’s Weizmann Institute of Science produced a movie display called Cinema 3D that uses special lenses and mirrors to allow viewers to watch 3-D movies in a theater without having to wear those clunky 3-D glasses.
  • A new deep-learning algorithm can predict human interactions more accurately than ever before, by training itself on footage from TV shows like “Desperate Housewives” and “The Office.”
  • A group from MIT and Harvard University developed an algorithm that may help astronomers produce the first image of a black hole, stitching together telescope data to essentially turn the planet into one large telescope dish.

Tech to help with health

  • A team produced a robot that can help schedule and assign tasks by learning from humans, in fields like medicine and the military.
  • Researchers came up with an algorithm for identifying organs in fetal MRI scans to extensively evaluate prenatal health.
  • A wireless device called EQ-Radio can tell if you’re excited, happy, angry, or sad, by measuring breathing and heart rhythms.

Algorithms, systems and networks

  • A system called “Polaris” was found to load web pages 34 percent faster by decreasing network trips.
  • A team analyzed ant-colony behavior to create better algorithms for network communication, for applications such as social networks and collective decision-making among robot swarms.
  • Researchers trained neural networks to explain themselves by providing rationales for their decisions.

Data sets while preserving their fundamental

One way to handle big data is to shrink it. If you can identify a small subset of your data set that preserves its salient mathematical relationships, you may be able to perform useful analyses on it that would be prohibitively time consuming on the full set.

The methods for creating such “coresets” vary according to application, however. Last week, at the Annual Conference on Neural Information Processing Systems, researchers from MIT’s Computer Science and Artificial Intelligence Laboratory and the University of Haifa in Israel presented a new coreset-generation technique that’s tailored to a whole family of data analysis tools with applications in natural-language processing, computer vision, signal processing, recommendation systems, weather prediction, finance, and neuroscience, among many others.

“These are all very general algorithms that are used in so many applications,” says Daniela Rus, the Andrew and Erna Viterbi Professor of Electrical Engineering and Computer Science at MIT and senior author on the new paper. “They’re fundamental to so many problems. By figuring out the coreset for a huge matrix for one of these tools, you can enable computations that at the moment are simply not possible.”

As an example, in their paper the researchers apply their technique to a matrix — that is, a table — that maps every article on the English version of Wikipedia against every word that appears on the site. That’s 1.4 million articles, or matrix rows, and 4.4 million words, or matrix columns.

That matrix would be much too large to analyze using low-rank approximation, an algorithm that can deduce the topics of free-form texts. But with their coreset, the researchers were able to use low-rank approximation to extract clusters of words that denote the 100 most common topics on Wikipedia. The cluster that contains “dress,” “brides,” “bridesmaids,” and “wedding,” for instance, appears to denote the topic of weddings; the cluster that contains “gun,” “fired,” “jammed,” “pistol,” and “shootings” appears to designate the topic of shootings.

Joining Rus on the paper are Mikhail Volkov, an MIT postdoc in electrical engineering and computer science, and Dan Feldman, director of the University of Haifa’s Robotics and Big Data Lab and a former postdoc in Rus’s group.

The researchers’ new coreset technique is useful for a range of tools with names like singular-value decomposition, principal-component analysis, and latent semantic analysis. But what they all have in common is dimension reduction: They take data sets with large numbers of variables and find approximations of them with far fewer variables.

In this, these tools are similar to coresets. But coresets are application-specific, while dimension-reduction tools are general-purpose. That generality makes them much more computationally intensive than coreset generation — too computationally intensive for practical application to large data sets.

The researchers believe that their technique could be used to winnow a data set with, say, millions of variables — such as descriptions of Wikipedia pages in terms of the words they use — to merely thousands. At that point, a widely used technique like principal-component analysis could reduce the number of variables to mere hundreds, or even lower.

The researchers’ technique works with what is called sparse data. Consider, for instance, the Wikipedia matrix, with its 4.4 million columns, each representing a different word. Any given article on Wikipedia will use only a few thousand distinct words. So in any given row — representing one article — only a few thousand matrix slots out of 4.4 million will have any values in them. In a sparse matrix, most of the values are zero.

Crucially, the new technique preserves that sparsity, which makes its coresets much easier to deal with computationally. Calculations become lot easier if they involve a lot of multiplication by and addition of zero.

System ranked most powerful in New England

The new TX-Green computing system at the MIT Lincoln Laboratory Supercomputing Center (LLSC) has been named the most powerful supercomputer in New England, 43rd most powerful in the U.S., and 106th most powerful in the world. A team of experts at TOP500 ranks the world’s 500 most powerful supercomputers biannually. The systems are ranked based on a LINPACK Benchmark, which is a measure of a system’s floating-point computing power, i.e., how fast a computer solves a dense system of linear equations.

Established in early 2016, the LLSC was developed to enhance computing power and accessibility for more than 1,000 researchers across the laboratory. The LLSC uses interactive supercomputing to augment the processing power of desktop systems to process large sets of sensor data, create high-fidelity simulations, and develop new algorithms. Located in Holyoke, Massachusetts, the new system is the only zero-carbon supercomputer on the TOP500 list; it uses energy from a mixture of hydroelectric, wind, solar, and nuclear sources.

In November, Dell EMC installed a new petaflop-scale system, which consists of 41,472 Intel processor cores and can compute 1015 operations per second. Compared to LLSC’s previous technology, the new system provides 6 times more processing power and 20 times more bandwidth. This technology enables research in several laboratory research areas, such as space observation, robotic vehicles, communications, cybersecurity, machine learning, sensor processing, electronic devices, bioinformatics, and air traffic control.

The LLSC mission is to address supercomputing needs, develop new supercomputing capabilities and technologies, and collaborate with MIT campus supercomputing initiatives. “The LLSC vision is to enable the brilliant scientists and engineers at Lincoln Laboratory to analyze and process enormous amounts of information with complex algorithms,” says Jeremy Kepner, Lincoln Laboratory Fellow and head of the LLSC. “Our new system is one of the largest on the East Coast and is specifically focused on enabling new research in machine learning, advanced physical devices, and autonomous systems.”

Because the new processors are similar to the prototypes developed at the laboratory more than two decades ago, the new petaflop system is compatible with all existing LLSC software. “We have had many years to prepare our computing system for this kind of processor,” Kepner says. “This new system is essentially a plug-and-play solution.”

After establishing the Supercomputing Center and one of the top systems in the world, the LLSC team will continue to upgrade and expand supercomputing at the laboratory. Says Kepner: “Our hope is that this system is the first of many such large-scale systems at Lincoln Laboratory.”

Technology work together

“When you’re part of a community, you want to leave it better than you found it,” says Keertan Kini, an MEng student in the Department of Electrical Engineering, or Course 6. That philosophy has guided Kini throughout his years at MIT, as he works to improve policy both inside and out of MIT.

As a member of the Undergraduate Student Advisory Group, former chair of the Course 6 Underground Guide Committee, member of the Internet Policy Research Initiative (IPRI), and of the Advanced Network Architecture group, Kini’s research focus has been in finding ways that technology and policy can work together. As Kini puts it, “there can be unintended consequences when you don’t have technology makers who are talking to policymakers and you don’t have policymakers talking to technologists.” His goal is to allow them to talk to each other.

At 14, Kini first started to get interested in politics. He volunteered for President Obama’s 2008 campaign, making calls and putting up posters. “That was the point I became civically engaged,” says Kini. After that, he was campaigning for a ballot initiative to raise more funding for his high school, and he hasn’t stopped being interested in public policy since.

High school was also where Kini became interested in computer science. He took a computer science class in high school on the recommendation of his sister, and in his senior year, he started watching computer science lectures on MIT OpenCourseWare (OCW) by Hal Abelson, a professor in MIT’s Department of Electrical Engineering and Computer Science.

“That lecture reframed what computer science was. I loved it,” Kini recalls. “The professor said ‘it’s not about computers, and it’s not about science’. It might be an art or engineering, but it’s not science, because what we’re working with are idealized components, and ultimately the power of what we can actually achieve with them is not based so much on physical limitations so much as the limitations of the mind.”

In part thanks to Abelson’s OCW lectures, Kini came to MIT to study electrical engineering and computer science. Kini is currently pursuing an MEng in electrical engineering and computer science, a fifth-year master’s program following his undergraduate studies in electrical engineering and computer science.

Combining two disciplines

Kini set his policy interest to the side his freshman year, until he took 6.805J (Foundations of Information Policy), with Abelson, the same professor who inspired Kini to study computer science. After taking Abelson’s course, Kini joined him and Daniel Weitzner, a principal research scientist in the Computer Science and Artificial Intelligence Laboratory, in putting together a big data and privacy workshop for the White House in the wake of the Edward Snowden leak of classified information from the National Security Agency. Four years later, Kini is now a teaching assistant for 6.805J.

With Weitzner as his advisor, Kini went on to work on a SuperUROP, an advanced version of the Undergraduate Research Opportunities Program in which students take on their own research project for a full year. Kini’s project focused on making it easier for organizations that had experienced a cybersecurity breach to share how the breach happened with other organizations, without accidentally sharing private or confidential information as well.

Typically, when a security breach happens, there is a “human bottleneck,” as Kini puts it. Humans have to manually check all information they share with other organizations to ensure they don’t share private information or get themselves into legal hot water. The process is time-consuming, slowing down the improvement of cybersecurity for all organizations involved. Kini created a prototype of a system that could automatically screen information about cybersecurity breaches, determining what data had to be checked by a human, and what was safe to send along.

Once finished with his SuperUROP, Kini became involved in the development of Votemate, a web app designed to simplify the voter registration process in all 50 states.

Kini’s interest in Votemate wasn’t only about increasing voter registration. “I think most people in this nation are centrist, and one of the reasons our political system gets polarized is because people who are polarized primarily turn out to vote,” he says. “I think the only reliable way to fix that is to get more people to turn out to vote.”

Shaping policy on campus

Kini is also involved in making changes within the Institute. “I feel like the same interest that’s gotten me interested in policy is the same thing that’s gotten me interested in working with the Department of Electrical Engineering and Computer Science,” Kini admits.

As a member of the Undergraduate Student Advisory Group (USAGE), Kini has been involved in exploring ways to revitalize the electrical engineering curriculum, redesigning the undergraduate lounge, and compiling a list of the resources available to Course 6 students. On the reason for the list of resources, Kini recalls, “When I was a senior, I realized there were some resources that I had no idea about. And this was after I had been involved in the department and USAGE for 5 years! I should have known.”

Paving a path to medicine

During January of her junior year at MIT, Caroline Colbert chose to do a winter externship at Massachusetts General Hospital (MGH). Her job was to shadow the radiation oncology staff, including the doctors that care for patients and medical physicists that design radiation treatment plans.

Colbert, now a senior in the Department of Nuclear Science and Engineering (NSE), had expected to pursue a career in nuclear power. But after working in a medical environment, she changed her plans.

She stayed at MGH to work on building a model to automate the generation of treatment plans for patients who will undergo a form of radiation therapy called volumetric-modulated arc therapy (VMAT). The work was so interesting that she is still involved with it and has now decided to pursue a doctoral degree in medical physics, a field that allows her to blend her training in nuclear science and engineering with her interest in medical technologies.

She’s even zoomed in on schools with programs that have accreditation from the Commission on Accreditation of Medical Physics Graduate Programs so she’ll have the option of having a more direct impact on patients. “I don’t know yet if I’ll be more interested in clinical work, research, or both,” she says. “But my hope is to work in a hospital setting.”

Many NSE students and faculty focus on nuclear energy technologies. But, says Colbert, “the department is really supportive of students who want to go into other industries.”

It was as a middle school student that Colbert first became interested in engineering. Later, in a chemistry class, a lesson about nuclear decay set her on a path towards nuclear science and engineering. “I thought it was so cool that one element can turn into another,” she says. “You think of elements as the fundamental building blocks of the physical world.”

Colbert’s parents, both from the Boston area, had encouraged her to apply to MIT. They also encouraged her towards the medical field. “They loved the idea of me being a doctor, and then when I decided on nuclear engineering, they wanted me to look into medical physics,” she says. “I was trying to make my own way. But when I did look seriously into medical physics, I had to admit that my parents were right.”

At MGH, Colbert’s work began with searching for practical ways to improve the generation of VMAT treatment plans. As with another form of radiation therapy called intensity-modulated radiation therapy (IMRT), the technology focuses radiation doses on the tumor and away from the healthy tissue surrounding it. The more accurate the dosing, the fewer side effects patients have after therapy.

With VMAT, a main challenge is in devising an accurate individualized treatment plan. Each plan is customized specifically to the patient’s anatomy. This design process is well defined for IMRT, which uses a set of intersecting beams to deliver radiation. VMAT also intersects beams but rotates them around the patient. “There are more degrees of freedom, so it should provide more accurate treatment, but it’s also more computationally difficult to optimize an individual treatment plan,” says Colbert.

Colbert spent the second half of her junior year developing improved algorithms under the supervision of Michael Young, a medical physics doctoral student at the University of Massachusetts and a research assistant at MGH. The idea was to use existing IMRT plans from anatomically similar patients as a starting point for developing a customized VMAT plan. “We needed to start the optimization algorithm in a place that was already good enough and would only get better from there,” she says.

Her work involved helping to build a database of existing IMRT radiation therapy plans used to treat MGH patients. She then worked on determining the search criteria required to pull the best information from the database to seed a starter plan that is primed for optimization for VMAT. The work drew on Colbert’s side-interest in computer science, which had grown out of a programming course she’d taken during an earlier January session at MIT.