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David Bradwell MNG ?06, a doctoral candidate in Professor Donald Sadoway?s lab, was selected for his efforts to build a cheap, reliable battery that could store renewable energy.
Timothy Lu ?03, MNG ?03, PhD ?08, an assistant professor of electrical engineering and computer science and a member of the Research Laboratory of Electronics, was recognized for engineering viruses to destroy biofilms.
Jacob Hanna, a fellow at the Whitehead Institute, was named to the list for his work in reprogramming cells to combat diseases;
Philip Low, a research affiliate in the MIT Media Lab's Synthetic Neurobiology group, was cited for his work on portable devices for monitoring brain activity.
?Each year, Technology Review selects 35 innovators under the age of 35 who we believe are transforming technology. Discovering these amazing young men and women is one of the highlights of the year for us,? said Jason Pontin, the magazine?s editor in chief and publisher. ?We celebrate their success and look forward to their continued advancement of technology in their respective fields.?
Bradwell, Hanna, Lu, Low and the other TR35 winners for 2010 will be featured in the September/October issue of Technology Review and online at www.technologyreview.com/tr35/. In addition, the EmTech@MIT 2010 Conference, to be held Sept. 21-23 at MIT, will honor the winners with a dedicated awards ceremony and in a series of ?Meet the TR35? presentations.
[On July 1, 2010, ESG joined DUE as part of the Office of Experiential Learning]
If you travel to the sixth floor of Building 24, you will find a unique freshman learning community. Instead of lecture halls, you will find small, informal classrooms. The common space, which includes couches, a hammock and a kitchen, encourages students to gather and discuss ideas, work through challenges, and connect as a community. The environment fosters frequent interaction between students, faculty and staff both inside and outside the classroom. This is the home of the Experimental Study Group (ESG).
Experimental Study Group (ESG): A dynamic educational community
Each year, 50 freshmen enroll in ESG?s alternative academic program that offers a more personalized approach to the core freshman subjects. What exactly does that mean? It means that ESG students take the same subjects as their mainstream peers, such as 18.01, 8.01 or a HASS subject, but they do so in a learning environment where:
Class size = 5-10 students;
Classes are highly interactive;
Students influence the pace of the classes;
Teaching is the priority
ESG embraces the philosophy that ?education works best when everyone is involved and active.? The small classes provide many opportunities for students to interact with the instructors and fellow students. In the classroom, students are encouraged to ask questions and experiment with novel ways of learning the material. Outside the classroom, collaborative learning is fundamental to the ESG community environment. Opportunities for students to engage faculty, staff and peers in problem solving and discussions are pervasive.
"Normativity is a careful, rigorous account of the meanings of the basic normative terms: good, virtue, correct, ought, should, and must. Along the way, Thomson refutes almost everything other philosophers have said about these topics. It is a very important book." ? Gilbert Harman, Princeton University
Groundbreaking treatise
Is there such a thing as an ideal world, one to which people are striving when they make judgments about what is "good" or "bad"? Is saying a person is "good" the same as saying a toaster is "good?" Is "correctness" the same as "goodness?"
These and other fundamental ethical questions were up for debate as distinguished moral philosophers gathered at MIT on June 11 for a daylong conference on Normativity ? a groundbreaking treatise by MIT philosophy professor emeritus Judith Jarvis Thomson. An expanded version of Thomson's Carus Lectures, the treatise illuminates the branch of philosophy concerned with value.
?Debate was vigorous, lively and good humored ? in all the ways that humor can be good!? said Professor Richard Holton, head of the Philosophy Section, who planned the conference, which filled Room D461 at the Stata Center to capacity.
Distinguished moral philosophers gather
Providing context for the event, Holton noted, ?Ethics has always been a central question in philosophy, both because many people look to philosophy for answers on what we can do, and because it can seem hard to fit ethics into our picture of the world. Judy has never been shy of using philosophy to say what we can do (she has, for example, famous views on the rights of abortion and of self-defense), but in this volume she is concerned with the more theoretical question of the nature of ethics, and of normativity more generally.?
Some of the most important moral philosophers of the day attended the gathering, among them Professor Frances Kamm of Harvard University and Professor Jonathan Vogel of Amherst College. Three eminent scholars gave presentations at the event: Michael Smith, the McCosh Professor of Philosophy at Princeton University; Peter Railton, the John Stephenson Perrin Professor of Philosophy at the University of Michigan; and Gideon Rosen, the Stuart Professor of Philosophy and chair of the Council of the Humanities at Princeton.
Thomson concludes that "consequentialism" is flawed
One major conclusion Thomson draws in her work is that the theory called "consequentialism," which argues that goodness is determined by what will maximize happiness, is fatally flawed.
?There are many classical objections [to consequentialism],? Thomson said. ?For example, what if by killing one person I could make people as a whole a lot happier? That?s not going to make it OK to kill the one. So that theory looks just false. A deeper objection is that it is incoherent.?
"This much anticipated book intriguingly and surprisingly broadens the scope of the philosophy of normativity. Impressively broad and deeply insightful." ? Ernest Sosa, Rutgers University
How things ought to behave
Thomson?s ambitious book separates normative judgments into two sub-kinds: directives, which concern what people ought to do (or what functions objects ought to perform); and evaluatives, which deal with how well someone or something performs.
Examples of directives include that A ought to be nice to his brother and that B ought to mop up that spill. Examples of evaluatives include that C is a good soccer player and that D is a good toaster, as well as that E is a good human being. In Normativity, Thomson describes how judgments of these two sub-kinds interconnect and what makes them true when they are true.
?[Thomson] arrives at a simple answer to the question of how things ought to behave,? Holton said. ?If a toaster didn't toast it would be defective; if an umbrella didn't keep you dry it would be defective. In general a thing ought to do whatever it needs to do to avoid being defective. And this is true of human beings too.?
A lively debate ? with humor
Speakers raised various objections to Thomson?s theories, which prompted a lively debate. Smith and Railton are both consequentialsts, and so both sought to defend their views from Thomson's criticism, Holton said. Smith wanted to dispute her whole approach, and Railton sought to reformulate consequentialism so that her criticisms had no bite, he said.
Rosen questioned whether what a thing ought to do is really what saves it from being defective. ?What do we say when the light comes on to tell you that your car's ignition system is not working? Should we say that the light ought to be on? In a sense, yes, if the ignition system is indeed faulty. But in another sense no, since the system ought not to be faulty,? Holton summarized, noting that Rosen concluded that there is more to the use of 'ought' than Thomson allows.
Normativity goes beyond 'good' and 'bad'
In an interview after the conference, Thomson said, ?People get focused on the words ?good? and ?bad,? but there?s a lot more to normativity than that. There are a lot of judgments that are evaluative that aren?t about whether something is good or bad. You might say about a certain comedy that it?s a witty comedy, for example; that is an evaluative judgment about it."
While judging something to be witty might appear to be an expression of pure preference, Thomson said that such a judgment is factual as well as evaluative. ?Suppose someone asks me for an example of a witty story, and I say that ?John walked downstairs? is a witty story. Then I spoke falsely, because if that is the whole of the story, then as a matter of fact, it isn?t a witty story. (Though people might well think my offering that as an example of a witty story was itself funny),? she said.
?People have the sense that there?s an uncrossable gap between evaluative and non-evaluative judgments, and that?s a serious mistake,? Thomson said. ?It makes the evaluative appear to be mysterious and undecidable.?
A book with catalyzing force
MIT?s conference was one of several events sparked by the publication of Thomson?s book. In April, the American Philosophical Association?s Pacific Division held a symposium on the book, which will be published in a forthcoming issue of the journal Philosophical Studies, and another symposium on the book will be published in a forthcoming issue of the English journal Analysis.
A plane that lands like a bird
Everyone knows what it's like for an airplane to land: the slow maneuvering into an approach pattern, the long descent, and the brakes slamming on as soon as the plane touches down, which seems to just barely bring it to a rest a mile later. Birds, however, can switch from barreling forward at full speed to lightly touching down on a target as narrow as a telephone wire. Why can't an airplane be more like a bird?
MIT researchers have demonstrated a new control system that allows a foam glider with only a single motor on its tail to land on a perch, just like a pet parakeet. The work could have important implications for the design of robotic planes, greatly improving their maneuverability and potentially allowing them to recharge their batteries simply by alighting on power lines.
Birds can land so precisely because they take advantage of a complicated physical phenomenon called "stall." Even when a commercial airplane is changing altitude or banking, its wings are never more than a few degrees away from level. Within that narrow range of angles, the airflow over the plane's wings is smooth and regular, like the flow of water around a small, smooth stone in a creek bed.
A bird approaching its perch, however, will tilt its wings back at a much sharper angle. The airflow over the wings becomes turbulent, and large vortices ? whirlwinds ? form behind the wings. The effects of the vortices are hard to predict: If a plane tilts its wings back too far, it can fall out of the sky. Hence the name "stall."
The smooth airflow over the wings of a normally operating plane is well-understood mathematically; as a consequence, engineers are highly confident that a commercial airliner will respond to the pilot's commands as intended. But stall is a much more complicated phenomenon: Even the best descriptions of it are time-consuming to compute.
Reap the whirlwind
To design their control system, MIT Associate Professor Russ Tedrake, a member of the Computer Science and Artificial Intelligence Laboratory, and Rick Cory, a PhD student in Tedrake's lab who defended his dissertation this spring, first developed their own mathematical model of a glider in stall. For a range of launch conditions, they used the model to calculate sequences of instructions intended to guide the glider to its perch. "It gets this nominal trajectory," Cory explains. "It says, 'If this is a perfect model, this is how it should fly.'" But, he adds, "because the model is not perfect, if you play out that same solution, it completely misses."
So Cory and Tedrake also developed a set of error-correction controls that could nudge the glider back onto its trajectory when location sensors determined that it had deviated from it. By using innovative techniques developed at MIT's Laboratory for Information and Decision Systems, they were able to precisely calculate the degree of deviation that the controls could compensate for. The addition of the error-correction controls makes a trajectory look like a tube snaking through space: The center of the tube is the trajectory calculated using Cory and Tedrake's model; the radius of the tube describes the tolerance of the error-correction controls.
The control system ends up being, effectively, a bunch of tubes pressed together like a fistful of straws. If the glider goes so far off course that it leaves one tube, it will still find itself in another. Once the glider is launched, it just keeps checking its position and executing the command that corresponds to the tube in which it finds itself. The design of the system earned Cory Boeing?s 2010 Engineering Student of the Year Award.
The measure of air resistance against a body in flight is known as the "drag coefficient." A cruising plane tries to minimize its drag coefficient, but when it's trying to slow down, it tilts its wings back in order to increase drag. Ordinarily, it can't tilt back too far, for fear of stall. But because Cory and Tedrake's control system takes advantage of stall, the glider, when it's landing, has a drag coefficient that's four to five times that of other aerial vehicles.
A high-speed video of the researchers' computer-controlled glider landing on a suspended string perch. Video courtesy of Russ Tedrake and Rick Cory (view more videos and images)
From spy planes to fairies
For some time, the U.S. Air Force has been interested in the possibility of unmanned aerial vehicles that could land in confined spaces and has been funding and monitoring research in the area. "What Russ and Rick and their team is doing is unique," says Gregory Reich of the Air Force Research Laboratory. "I don't think anyone else is addressing the flight control problem in nearly as much detail." Reich points out, however, that in their experiments, Cory and Tedrake used data from wall-mounted cameras to gauge the glider's position, and the control algorithms ran on a computer on the ground, which transmitted instructions to the glider. "The computational power that you may have on board a vehicle of this size is really, really limited," Reich says. Even though the MIT researchers' course correction algorithms are simple, they may not be simple enough.
Tedrake believes, however, that computer processors powerful enough to handle his and Cory's control algorithms are only a few years off. In the meantime, his lab has already begun to address the problem of moving the glider's location sensors onboard, and although Cory will be moving to California to take a job researching advanced robotics techniques for Disney, he hopes to continue collaborating with Tedrake. "I visited the air force, and I visited Disney, and they actually have a lot in common," Cory says. "The air force wants an airplane that can land on a power line, and Disney wants a flying Tinker Bell that can land on a lantern. But the technology's similar."
Don Sadoway on innovation in energy storage
In a lecture that could have been titled, "Better Education through Chemistry," Don Sadoway begins with solar energy, grid-level storage and liquid metal batteries and moves into education innovation, sharing creative ways to teach chemistry.
"How do we think against the grain? Pose the right question." ? Donald Sadoway