Which Technologies Get Better Faster?

In a nutshell, the researchers found that the greater a technology's complexity, the more slowly it changes and improves over time. They devised a way of mathematically modeling complexity, breaking a system down into its individual components and then mapping all the interconnections between these components.

"It gives you a way to think about how the structure of the technology affects the rate of improvement," says Jessika Trancik, assistant professor of engineering systems at MIT. Trancik wrote the paper with James McNerney, a graduate student at Boston University (BU); Santa Fe Institute Professor Doyne Farmer; and BU physics professor Sid Redner. It appears online this week in theProceedings of the National Academy of Sciences.

The team was inspired by the complexity of energy-related technologies ranging from tiny transistors to huge coal-fired powerplants. They have tracked how these technologies improve over time, either through reduced cost or better performance, and, in this paper, develop a model to compare that progress to the complexity of the design and the degree of connectivity among its different components.

The authors say the approach they devised for comparing technologies could, for example, help policymakers mitigate climate change: By predicting which low-carbon technologies are likeliest to improve rapidly, their strategy could help identify the most effective areas to concentrate research funding. The analysis makes it possible to pick technologies"not just so they will work well today, but ones that will be subject to rapid development in the future," Trancik says.

Besides the importance of overall design complexity in slowing the rate of improvement, the researchers also found that certain patterns of interconnection can create bottlenecks, causing the pace of improvements to come in fits and starts rather than at a steady rate.

"In this paper, we develop a theory that shows why we see the rates of improvement that we see," Trancik says. Now that they have developed the theory, she and her colleagues are moving on to do empirical analysis of many different technologies to gauge how effective the model is in practice."We're doing a lot of work on analyzing large data sets" on different products and processes, she says.

For now, she suggests, the method is most useful for comparing two different technologies"whose components are similar, but whose design complexity is different." For example, the analysis could be used to compare different approaches to next-generation solar photovoltaic cells, she says. The method can also be applied to processes, such as improving the design of supply chains or infrastructure systems."It can be applied at many different scales," she says.

Koen Frenken, professor of economics of innovation and technological change at Eindhoven University of Technology in the Netherlands, says this paper"provides a long-awaited theory" for the well-known phenomenon of learning curves."It has remained a puzzle why the rates at which humans learn differ so markedly among technologies. This paper provides an explanation by looking at the complexity of technology, using a clever way to model design complexity."

Frenken adds,"The paper opens up new avenues for research. For example, one can verify their theory experimentally by having human subjects solve problems with different degrees of complexity." In addition, he says,"The implications for firms and policymakers {are} that R&D should not only be spent on invention of new technologies, but also on simplifying existing technologies so that humans will learn faster how to improve these technologies."

Ultimately, the kind of analysis developed in this paper could become part of the design process -- allowing engineers to"design for rapid innovation," Trancik says, by using these principles to determine"how you set up the architecture of your system."

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Physicist Accelerates Simulations of Thin Film Growth

Jacques Amar, Ph.D., professor of physics at the University of Toledo (UT), studies the modeling and growth of materials at the atomic level. He uses Ohio Supercomputer Center (OSC) resources and Kinetic Monte Carlo (KMC) methods to simulate the molecular beam epitaxy (MBE) process, where metals are heated until they transition into a gaseous state and then reform as thin films by condensing on a wafer in single-crystal thick layers.

"One of the main advantages of MBE is the ability to control the deposition of thin films and atomic structures on the atomic scale in order to create nanostructures," explained Amar.

Thin films are used in industry to create a variety of products, such as semiconductors, optical coatings, pharmaceuticals and solar cells.

"Ohio's status as a worldwide manufacturing leader has led OSC to focus on the field of advanced materials as one of our areas of primary support," noted Ashok Krishnamurthy, co-interim co-executive director of the center."As a result, numerous respected physicists, chemists and engineers, such as Dr. Amar, have accessed OSC computation and storage resources to advance their vital materials science research."

Recently, Amar leveraged the center's powerful supercomputers to implement a"first-passage time approach" to speed up KMC simulations of the creation of materials just a few atoms thick.

"The KMC method has been successfully used to carry out simulations of a wide variety of dynamical processes over experimentally relevant time and length scales," Amar noted."However, in some cases, much of the simulation time can be 'wasted' on rapid, repetitive, low-barrier events."

While a variety of approaches to dealing with the inefficiencies have been suggested, Amar settled on using a first-passage-time (FPT) approach to improve KMC processing speeds. FPT, sometimes also called first-hitting-time, is a statistical model that sets a certain threshold for a process and then estimates certain factors, such as the probability that the process reaches that threshold within a certain amount time or the mean time until which the threshold is reached.

"In this approach, one avoids simulating the numerous diffusive hops of atoms, and instead replaces them with the first-passage time to make a transition from one location to another," Amar said.

In particular, Amar and colleagues from the UT department of Physics and Astronomy targeted two atomic-level events for testing the FPT approach: edge-diffusion and corner rounding. Edge-diffusion involves the"hopping" movement of surface atoms -- called adatoms -- along the edges of islands, which are formed as the material is growing. Corner rounding involves the hopping of adatoms around island corners, leading to smoother islands.

Amar compared the KMC-FPT and regular KMC simulation approaches using several different models of thin film growth: Cu/Cu(100), fcc(100) and solid-on-solid (SOS). Additionally, he employed two different methods for calculating the FPT for these events: the mean FPT (MFPT), as well as the full FPT distribution.

"Both methods provided"very good agreement" between the FPT-KMC approach and regular KMC simulations," Amar concluded."In addition, we find that our FPT approach can lead to a significant speed-up, compared to regular KMC simulations."

Amar's FPT-KMC approach accelerated simulations by a factor of approximately 63 to 100 times faster than the corresponding KMC simulations for the fcc(100) model. The SOS model was improved by a factor of 36 to 76 times faster. For the Cu/Cu(100) tests, speed-up factors of 31 to 42 and 22 to 28 times faster were achieved, respectively, for simulations using the full FPT distribution and MFPT calculations.

Amar's research was supported through multiple grants from the National Science Foundation, as well as by a grant of computer time from OSC.

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Beyond Smart Phones: Sensor Network to Make 'Smart Cities' Envisioned

Computer scientists, electrical and computer engineers, and mathemati­cians at the TU Darmstadt and the University of Kassel have joined forces and are working on implementing that vision under their"Cocoon" project. The backbone of a"smart" city is a communications network consisting of sen­sors that receive streams of data, or signals, analyze them, and trans­mit them onward. Such sensors thus act as both receivers and trans­mit­ters, i.e., represent trans­ceivers. The networked communications involved oper­ates wire­lessly via radio links, and yields added values to all partici­pants by analyzing the input data involved. For example, the"Smart Home" control system already on the market allows networking all sorts of devices and automatically regulating them to suit demands, thereby alleg­edly yielding energy savings of as much as fifteen percent.

"Smart Home" might soon be followed by"Smart Hospital,""Smart Indus­try," or"Smart Farm," and even"smart" systems tailored to suit mobile net­works are feasible. Traffic jams may be avoided by, for example, car-to-car or car-to-environment (car-to-X) communications. Health-service sys­tems might also benefit from mobile, sensor communications whenever patients need to be kept supplied with information tailored to suit their health­care needs while underway. Furthermore, sensors on their bodies could assess the status of their health and automatically transmit calls for emergency medical assistance, whenever necessary.

"Smart" and mobile, thanks to beam forming

The researchers regard the ceaseless travels of sensors on mobile systems and their frequent entries into/exits from instrumented areas as the major hurdle to be overcome in implementing their vision of"smart" cities. Sensor-aided devices will have to deal with that by responding to subtle changes in their environments and flexibly, efficiently, regulating the quali­ties of received and transmitted signals. Beam forming, a field in which the TU Darmstadt's Institute for Communications Technology is active, should help out there. On that subject, Prof. Rolf Jakoby of the TU Darmstadt's Electrical Engineering and Information Technology Dept. remarked that,"Current types of antennae radiate omnidirectionally, like light bulbs. We intend to create conditions, under which antennae will, in the future, behave like spotlights that, once they have located a sought device, will track it, while suppressing interference by stray electromag­netic radiation from other devices that might also be present in the area."

Such antennae, along with transceivers equipped with them, are thus recon­figurable, i.e., adjustable to suit ambient conditions by means of onboard electronic circuitry or remote controls. Working in col­lab­or­a­tion with an industrial partner, Jakoby has already equipped terres­trial digital-television (TDTV) transmitters with reconfigurable amplifiers that allow amplifying transmitted-signal levels by as much as ten percent. He added that,"If all of Germany's TDTV‑transmitters were equipped with such amp­li­fiers, we could shut down one nuclear power plant."

Frequency bands are a scarce resource

Reconfigurable devices also make much more efficient use of a scarce resource, freq­uency bands. Users have thus far been allocated rigorously defined frequency bands, where only fifteen to twenty percent of the capacities of even the more popular ones have been allocated. Beam forming might allow making more efficient use of them. Jakoby noted that,"This is an area that we are still taking a close look at, but we are well along the way toward understand­ing the system better." However, only a few uses of beam forming have emerged to date, since currently available systems are too expensive for mass applications.

Small, model networks are targeted

Yet another fundamental problem remains to be solved before"smart" cities may become realities. Sensor communications requires the cooper­a­tion of all devices involved, across all communications protocols, such as"Bluetooth," and across all networks, such as the European Global System for Mobile Communications (GSM) mobile-telephone network or wireless local-area networks (WLAN), which cannot be achieved with current devices, communications protocols, and networks. Jakoby explained that,"Con­verting all devices to a common communications protocol is infeas­ible, which is why we are seeking a new protocol that would be superim­posed upon everything and allow them to communicate via several proto­cols." Transmission channels would also have to be capable of handling a mas­sive flood of data, since, as Prof. Abdelhak Zoubir of the TU Darm­stadt's Electrical Engineer­ing and Information Technology Dept., the"Cocoon" project's coordinator, put it,"A"smart" Darm­stadt alone would surely involve a million sensors communicating with one another via satel­lites, mobile telephones, computers, and all of the other types of devices that we already have available. Furthermore, since a single, mobile sensor is readily capable of generating several hundred Meg­a­bytes of data annu­ally, new models for handling the communications of millions of such sen­sors that will more densely compress data in order to provide for error-free com­munica­tions will be needed. Several hurdles will thus have to be over­come before"smart" cities become reality. Nevertheless, the scientists working on the"Cocoon" project are convinced that they will be able to simulate a"smart" city incorporating various types of devices employing early versions of small, model networks.

Over the next three years, scientists at the TU Darmstadt will be receiving a total of 4.5 million Euros from the State of Hesse's Offensive for Devel­op­ing Scientific-Economic Excellence for their researches in conjunction with their"Cocoon -- Cooperative Sensor Communications" project.

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New Algorithm Offers Ability to Influence Systems Such as Living Cells or Social Networks

However, an MIT researcher has come up with a new computational model that can analyze any type of complex network -- biological, social or electronic -- and reveal the critical points that can be used to control the entire system.

Potential applications of this work, which appears as the cover story in the May 12 issue ofNature, include reprogramming adult cells and identifying new drug targets, says study author Jean-Jacques Slotine, an MIT professor of mechanical engineering and brain and cognitive sciences.

Slotine and his co-authors applied their model to dozens of real-life networks, including cell-phone networks, social networks, the networks that control gene expression in cells and the neuronal network of the C. elegans worm. For each, they calculated the percentage of points that need to be controlled in order to gain control of the entire system.

For sparse networks such as gene regulatory networks, they found the number is high, around 80 percent. For dense networks -- such as neuronal networks -- it's more like 10 percent.

The paper, a collaboration with Albert-Laszlo Barabasi and Yang-Yu Liu of Northeastern University, builds on more than half a century of research in the field of control theory.

Control theory -- the study of how to govern the behavior of dynamic systems -- has guided the development of airplanes, robots, cars and electronics. The principles of control theory allow engineers to design feedback loops that monitor input and output of a system and adjust accordingly. One example is the cruise control system in a car.

However, while commonly used in engineering, control theory has been applied only intermittently to complex, self-assembling networks such as living cells or the Internet, Slotine says. Control research on large networks has been concerned mostly with questions of synchronization, he says.

In the past 10 years, researchers have learned a great deal about the organization of such networks, in particular their topology -- the patterns of connections between different points, or nodes, in the network. Slotine and his colleagues applied traditional control theory to these recent advances, devising a new model for controlling complex, self-assembling networks.

"The area of control of networks is a very important one, and although much work has been done in this area, there are a number of open problems of outstanding practical significance," says Adilson Motter, associate professor of physics at Northwestern University. The biggest contribution of the paper by Slotine and his colleagues is to identify the type of nodes that need to be targeted in order to control complex networks, says Motter, who was not involved with this research.

The researchers started by devising a new computer algorithm to determine how many nodes in a particular network need to be controlled in order to gain control of the entire network. (Examples of nodes include members of a social network, or single neurons in the brain.)

"The obvious answer is to put input to all of the nodes of the network, and you can, but that's a silly answer," Slotine says."The question is how to find a much smaller set of nodes that allows you to do that."

There are other algorithms that can answer this question, but most of them take far too long -- years, even. The new algorithm quickly tells you both how many points need to be controlled, and where those points -- known as"driver nodes" -- are located.

Next, the researchers figured out what determines the number of driver nodes, which is unique to each network. They found that the number depends on a property called"degree distribution," which describes the number of connections per node.

A higher average degree (meaning the points are densely connected) means fewer nodes are needed to control the entire network. Sparse networks, which have fewer connections, are more difficult to control, as are networks where the node degrees are highly variable.

In future work, Slotine and his collaborators plan to delve further into biological networks, such as those governing metabolism. Figuring out how bacterial metabolic networks are controlled could help biologists identify new targets for antibiotics by determining which points in the network are the most vulnerable.

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Razing Seattle's Viaduct Doesn’t Guarantee Nightmare Commutes, Model Says

University of Washington statisticians have, for the first time, explored a different subject of uncertainty, namely surrounding how much commuters might benefit from the project. They found that relying on surface streets would likely have less impact on travel times than previously reported, and that different options' effects on commute times are not well known.

The research, conducted in 2009, was originally intended as an academic exercise looking at how to assess uncertainties in travel-time projections from urban transportation and land-use models. But the paper is being published amid renewed debate about the future of Seattle's waterfront thoroughfare.

"In early 2009 it was decided there would be a tunnel, and we said, 'Well, the issue is settled but it's still of academic interest,'" said co-author Adrian Raftery, a UW statistics professor."Now it has all bubbled up again."

The study was cited last month in a report by the Seattle Department of Transportation reviewing the tunnel's impact. It is now available online, and will be published in an upcoming issue of the journalTransportation Research: Part A.

The UW authors considered 22 commuter routes, eight of which currently include the viaduct. They compared a business-as-usual scenario, where a new elevated highway or a tunnel carries all existing traffic, against a worst-case scenario in which the viaduct is removed and no measures are taken to increase public transportation or otherwise mitigate the effects.

The study found that simply erasing the structure in 2010 would increase travel times a decade later for the eight routes that currently include the viaduct by 1.5 minutes to 9.2 minutes, with an average increase of 6 minutes. The uncertainty was fairly large, with zero change within the 95 percent confidence range for all the viaduct routes, and more than 20 minutes increase as a reasonable projection in a few cases. In the short term some routes along Interstate 5 were slightly slower, but by 2020 the travel times returned to today's levels.

"This indicates that over time removing the structure would increase commute times for people who use the viaduct by about six minutes, although there's quite a bit of uncertainty about exactly how much," Raftery said."In the rest of the region, on I-5, there's no indication that it would increase commute times at all."

The Washington State Department of Transportation had used a computer model in 2008 to explore travel times under various project scenarios. It found that the peak morning commute across downtown would be 10 minutes longer if the state relied on surface transportation. Shortly thereafter state and city leaders decided to build a tunnel.

The UW team in late 2009 ran the same travel model but added an urban land-use component that allows people and businesses to adapt over time -- for instance by moving, switching jobs or relocating businesses. It also included a statistical method that puts error bars around the travel-time projections.

"There is a big interest among transportation planners in putting an uncertainty range around modeling results," said co-author Hana Sevcikova, a UW research scientist who ran the model.

"Often in policy discussions there's interest in either one end or the other of an interval: How bad could things be if we don't make an investment, or if we do make an investment, are we sure that it's necessary?" Raftery said."The ends of the interval can give you a sense of that."

The UW study used a method called Bayesian statistics to combine computer models with actual data. Researchers used 2000 and 2005 land-use data and 2005 commute travel times to fine-tune the model. Bayesian statistics improves the model's accuracy and provides an uncertainty range around the model's projections.

The study used UrbanSim, an urban simulation model developed by co-author and former UW faculty member Paul Waddell, now a professor at the University of California, Berkeley. The model starts running in the year 2000, the viaduct is taken down in 2010 and the study focuses on peak morning commutes in the year 2020.

Despite renewed discussion, the authors are not taking a position on the debate.

"This is a scientific assessment. People could well say that six minutes is a lot, and it's worth whatever it takes {to avoid it}," Raftery said."To some extent it comes down to a value judgment, factoring in the economic and environmental impacts."

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Evolutionary Lessons for Wind Farm Efficiency

Senior Lecturer Dr Frank Neumann, from the School of Computer Science, is using a"selection of the fittest" step-by-step approach called"evolutionary algorithms" to optimise wind turbine placement. This takes into account wake effects, the minimum amount of land needed, wind factors and the complex aerodynamics of wind turbines.

"Renewable energy is playing an increasing role in the supply of energy worldwide and will help mitigate climate change," says Dr Neumann."To further increase the productivity of wind farms, we need to exploit methods that help to optimise their performance."

Dr Neumann says the question of exactly where wind turbines should be placed to gain maximum efficiency is highly complex."An evolutionary algorithm is a mathematical process where potential solutions keep being improved a step at a time until the optimum is reached," he says.

"You can think of it like parents producing a number of offspring, each with differing characteristics," he says."As with evolution, each population or 'set of solutions' from a new generation should get better. These solutions can be evaluated in parallel to speed up the computation."

Other biology-inspired algorithms to solve complex problems are based on ant colonies.

"Ant colony optimisation" uses the principle of ants finding the shortest way to a source of food from their nest.

"You can observe them in nature, they do it very efficiently communicating between each other using pheromone trails," says Dr Neumann."After a certain amount of time, they will have found the best route to the food -- problem solved. We can also solve human problems using the same principles through computer algorithms."

Dr Neumann has come to the University of Adelaide this year from Germany where he worked at the Max Planck Institute. He is working on wind turbine placement optimisation in collaboration with researchers at the Massachusetts Institute of Technology.

"Current approaches to solving this placement optimisation can only deal with a small number of turbines," Dr Neumann says."We have demonstrated an accurate and efficient algorithm for as many as 1000 turbines."

The researchers are now looking to fine-tune the algorithms even further using different models of wake effect and complex aerodynamic factors.

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EEG Headset With Flying Harness Lets Users 'Fly' by Controlling Their Thoughts

Creative director and Rensselaer MFA candidate Yehuda Duenyas describes the"Infinity Simulator" as a platform similar to a gaming console -- like the Wii or the Kinect -- writ large.

"Instead of you sitting and controlling gaming content, it's a whole system that can control live elements -- so you can control 3-D rigging, sound, lights, and video," said Duenyas, who works under the moniker"xxxy.""It's a system for creating hybrids of theater, installation, game, and ride."

Duenyas created the"Infinity Simulator" with a team of collaborators, including Michael Todd, a Rensselaer 2010 graduate in computer science. Duenyas will exhibit the new system in the art installation"The Ascent" on May 12 at Curtis R. Priem Experimental Media and Performing Arts Center (EMPAC).

Ten computer programs running simultaneously link the commercially available EEG headset to the computer-controlled 3-D flying harness and various theater systems, said Todd.

Within the theater, the rigging -- including the harness -- is controlled by a Stage Tech NOMAD console; lights are controlled by an ION console running MIDI show control; sound through MAX/MSP; and video through Isadora and Jitter. The"Infinity Simulator," a series of three C programs written by Todd, acts as intermediary between the headset and the theater systems, connecting and conveying all input and output.

"We've built a software system on top of the rigging control board and now have control of it through an iPad, and since we have the iPad control, we can have anything control it," said Duenyas."The 'Infinity Simulator' is the center; everything talks to the 'Infinity Simulator.'"

The May 12"The Ascent" installation is only one experience made possible by the new platform, Duenyas said.

"'The Ascent' embodies the maiden experience that we'll be presenting," Duenyas said."But we've found that it's a versatile platform to create almost any type of experience that involves rigging, video, sound, and light. The idea is that it's reactive to the users' body; there's a physical interaction."

Duenyas, a Brooklyn-based artist and theater director, specializes in experiential theater performances.

"The thing that I focus on the most is user experience," Duenyas said."All the shows I do with my theater company and on my own involve a lot of set and set design -- you're entering into a whole world. You're having an experience that is more than going to a show, although a show is part of it."

The"Infinity Simulator" stemmed from an idea Duenyas had for such a theatrical experience.

"It started with an idea that I wanted to create a simulator that would give people a feeling of infinity," Duenyas said. His initial vision was that of a room similar to a Cave Automated Virtual Environment -- a room paneled with projection screens -- in which participants would be able to float effortlessly in an environment intended to evoke a glimpse into infinity.

At Rensselaer, Duenyas took advantage of the technology at hand to explore his idea, first with a video game he developed in 2010, then -- working through the Department of the Arts -- with EMPAC's computer-controlled 3-D theatrical flying harness.

"The charge of the arts department is to allow the artists that they bring into the department to use technology to enhance what they've been doing already," Duenyas said."In coming here (EMPAC), and starting to translate our ideas into a physical space, so many different things started opening themselves up to us."

The 2010 video game, also developed with Todd, tracked the movements -- pitch and yaw -- of players suspended in a custom-rigged harness, allowing players to soar through simulated landscapes. Duenyas said that that game (also called the"Infinity Simulator") and the new platform are part of the same vision.

EMPAC Director Johannes Goebel saw the game on display at the 2010 GameFest and discussed the custom-designed 3-D theatrical flying rig in EMPAC with Duenyas. Working through the Arts Department, Duenyas submitted a proposal to work with the rig, and his proposal was accepted.

Duenyas and his team experimented -- first gaining peripheral control over the system, and then linking it to the EEG headset -- and created the Ascent installation as an initial project. In the installation, the Infinity Simulator is programmed to respond to relaxation.

"We're measuring two brain states -- alpha and theta -- waking consciousness and everyday brain computational processing," said Duenyas."If you close your eyes and take a deep breath, that processing power decreases. When it decreases below a certain threshold, that is the trigger for you to elevate."

As a user rises, their ascent triggers a changing display of lights, sound, and video. Duenyas said he wants to hint at transcendental experience, while keeping the door open for a more circumspect interpretation.

"The point is that the user is trying to transcend the everyday and get into this meditative state so they can have this experience. I see it as some sort of iconic spiritual simulator. That's the serious side," he said."There's also a real tongue-in-cheek side of my work: I want clouds, I want Terry Gilliam's animated fist to pop out of a cloud and hit you in the face. It's mixing serious religious symbology, but not taking it seriously."

The humor is prompted, in part, by the limitations of this earliest iteration of Duenyas' vision.

"It started with, 'I want to have a glimpse of infinity,' 'I want to float in space.' Then you get in the harness and you're like 'man, this harness is uncomfortable,'" he said."In order to achieve the original vision, we had to build an infrastructure, and I still see development of the infinity experience is a ways off; but what we can do with the infrastructure in a realistic time frame is create 'The Ascent,' which is going to be really fun, and totally other."

Creating the"Infinity Simulator" has prompted new possibilities.

"The vision now is to play with this fun system that we can use to build any experience," he said."It's sort of overwhelming because you could do so many things -- you could create a flight through cumulus clouds, you could create an augmented physicality parkour course where you set up different features in the room and guide yourself to different heights. It's limitless."

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Scientists Afflict Computers With 'Schizophrenia' to Better Understand the Human Brain

The researchers used a virtual computer model, or"neural network," to simulate the excessive release of dopamine in the brain. They found that the network recalled memories in a distinctly schizophrenic-like fashion.

Their results were published in April inBiological Psychiatry.

"The hypothesis is that dopamine encodes the importance-the salience-of experience," says Uli Grasemann, a graduate student in the Department of Computer Science at The University of Texas at Austin."When there's too much dopamine, it leads to exaggerated salience, and the brain ends up learning from things that it shouldn't be learning from."

The results bolster a hypothesis known in schizophrenia circles as the hyperlearning hypothesis, which posits that people suffering from schizophrenia have brains that lose the ability to forget or ignore as much as they normally would. Without forgetting, they lose the ability to extract what's meaningful out of the immensity of stimuli the brain encounters. They start making connections that aren't real, or drowning in a sea of so many connections they lose the ability to stitch together any kind of coherent story.

The neural network used by Grasemann and his adviser, Professor Risto Miikkulainen, is called DISCERN. Designed by Miikkulainen, DISCERN is able to learn natural language. In this study it was used to simulate what happens to language as the result of eight different types of neurological dysfunction. The results of the simulations were compared by Ralph Hoffman, professor of psychiatry at the Yale School of Medicine, to what he saw when studying human schizophrenics.

In order to model the process, Grasemann and Miikkulainen began by teaching a series of simple stories to DISCERN. The stories were assimilated into DISCERN's memory in much the way the human brain stores information-not as distinct units, but as statistical relationships of words, sentences, scripts and stories.

"With neural networks, you basically train them by showing them examples, over and over and over again," says Grasemann."Every time you show it an example, you say, if this is the input, then this should be your output, and if this is the input, then that should be your output. You do it again and again thousands of times, and every time it adjusts a little bit more towards doing what you want. In the end, if you do it enough, the network has learned."

In order to model hyperlearning, Grasemann and Miikkulainen ran the system through its paces again, but with one key parameter altered. They simulated an excessive release of dopamine by increasing the system's learning rate-essentially telling it to stop forgetting so much.

"It's an important mechanism to be able to ignore things," says Grasemann."What we found is that if you crank up the learning rate in DISCERN high enough, it produces language abnormalities that suggest schizophrenia."

After being re-trained with the elevated learning rate, DISCERN began putting itself at the center of fantastical, delusional stories that incorporated elements from other stories it had been told to recall. In one answer, for instance, DISCERN claimed responsibility for a terrorist bombing.

In another instance, DISCERN began showing evidence of"derailment"-replying to requests for a specific memory with a jumble of dissociated sentences, abrupt digressions and constant leaps from the first- to the third-person and back again.

"Information processing in neural networks tends to be like information processing in the human brain in many ways," says Grasemann."So the hope was that it would also break down in similar ways. And it did."

The parallel between their modified neural network and human schizophrenia isn't absolute proof the hyperlearning hypothesis is correct, says Grasemann. It is, however, support for the hypothesis, and also evidence of how useful neural networks can be in understanding the human brain.

"We have so much more control over neural networks than we could ever have over human subjects," he says."The hope is that this kind of modeling will help clinical research."

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Robot Engages Novice Computer Scientists

A product of CMU's famed Robotics Institute, Finch was designed specifically to make introductory computer science classes an engaging experience once again.

A white plastic, two-wheeled robot with bird-like features, Finch can quickly be programmed by a novice to say"Hello, World," or do a little dance, or make its beak glow blue in response to cold temperature or some other stimulus. But the simple look of the tabletop robot is deceptive. Based on four years of educational research sponsored by the National Science Foundation, Finch includes a number of features that could keep students busy for a semester or more thinking up new things to do with it.

"Students are more interested and more motivated when they can work with something interactive and create programs that operate in the real world," said Tom Lauwers, who earned his Ph.D. in robotics at CMU in 2010 and is now an instructor in the Robotics Institute's CREATE Lab."We packed Finch with sensors and mechanisms that engage the eyes, the ears -- as many senses as possible."

Lauwers has launched a startup company, BirdBrain Technologies, to produce Finch and now sells them online atwww.finchrobot.comfor$99 each.

"Our vision is to make Finch affordable enough that every student can have one to take home for assignments," said Lauwers, who developed the robot with Illah Nourbakhsh, associate professor of robotics and director of the CREATE Lab. Less than a foot long, Finch easily fits in a backpack and is rugged enough to survive being hauled around and occasionally dropped.

Finch includes temperature and light sensors, a three-axis accelerometer and a bump sensor. It has color-programmable LED lights, a beeper and speakers. With a pencil inserted in its tail, Finch can be used to draw pictures. It can be programmed to be a moving, noise-making alarm clock. It even has uses beyond a robot; its accelerometer enables it to be used as a 3-D mouse to control a computer display.

Robot kits suitable for students as young as 12 are commercially available, but often cost more than the Finch, Lauwers said. What's more, the idea is to use the robot to make computer programming lessons more interesting, not to use precious instructional time to first build a robot.

Finch is a plug-and-play device, so no drivers or other software must be installed beyond what is used in typical computer science courses. Finch connects with and receives power from the computer over a 15-foot USB cable, eliminating batteries and off-loading its computation to the computer. Support for a wide range of programming languages and environments is coming, including graphical languages appropriate for young students. Finch currently can be programmed with the Java and Python languages widely used by educators.

A number of assignments are available on the Finch Robot website to help teachers drop Finch into their lesson plans, and the website allows instructors to upload their own assignments or ideas in return for company-provided incentives. The robot has been classroom-tested at the Community College of Allegheny County, Pa., and by instructors in high school, university and after-school programs.

"Computer science now touches virtually every scientific discipline and is a critical part of most new technologies, yet U.S. universities saw declining enrollments in computer science through most of the past decade," Nourbakhsh said."If Finch can help motivate students to give computer science a try, we think many more students will realize that this is a field that they would enjoy exploring."

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Revolutionary New Paper Computer Shows Flexible Future for Smartphones and Tablets

"This is the future. Everything is going to look and feel like this within five years," says creator Roel Vertegaal, the director of Queen's University Human Media Lab."This computer looks, feels and operates like a small sheet of interactive paper. You interact with it by bending it into a cell phone, flipping the corner to turn pages, or writing on it with a pen."

The smartphone prototype, called PaperPhone is best described as a flexible iPhone -- it does everything a smartphone does, like store books, play music or make phone calls. But its display consists of a 9.5 cm diagonal thin film flexible E Ink display. The flexible form of the display makes it much more portable that any current mobile computer: it will shape with your pocket.

Dr. Vertegaal will unveil his paper computer on May 10 at 2 pm at the Association of Computing Machinery's CHI 2011 (Computer Human Interaction) conference in Vancouver -- the premier international conference of Human-Computer Interaction.

Being able to store and interact with documents on larger versions of these light, flexible computers means offices will no longer require paper or printers.

"The paperless office is here. Everything can be stored digitally and you can place these computers on top of each other just like a stack of paper, or throw them around the desk" says Dr. Vertegaal.

The invention heralds a new generation of computers that are super lightweight, thin-film and flexible. They use no power when nobody is interacting with them. When users are reading, they don't feel like they're holding a sheet of glass or metal.

An article on a study of interactive use of bending with flexible thinfilm computers is to be published at the conference in Vancouver, where the group is also demonstrating a thinfilm wristband computer called Snaplet.

The development team included researchers Byron Lahey and Win Burleson of the Motivational Environments Research Group at Arizona State University (ASU), Audrey Girouard and Aneesh Tarun from the Human Media Lab at Queen's University, Jann Kaminski and Nick Colaneri, director of ASU's Flexible Display Center, and Seth Bishop and Michael McCreary, the VP R&D of E Ink Corporation.

For more information, articles, videos, and high resolution photos, visithttp://www.humanmedialab.org/paperphone/andhttp://www.youtube.com/watch?v=Rl-qygUEE2c

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College Students' Use of Kindle DX Points to E-Reader’s Role in Academia

The UW last year was one of seven U.S. universities that participated in a pilot study of the Kindle DX, a larger version of the popular e-reader. UW researchers who study technology looked at how students involved in the pilot project did their academic reading.

"There is no e-reader that supports what we found these students doing," said first author Alex Thayer, a UW doctoral student in Human Centered Design and Engineering."It remains to be seen how to design one. It's a great space to get into, there's a lot of opportunity."

Thayer is presenting the findings in Vancouver, B.C. at the Association for Computing Machinery's Conference on Human Factors in Computing Systems, where the study received an honorable mention for best paper.

"Most e-readers were designed for leisure reading -- think romance novels on the beach," said co-author Charlotte Lee, a UW assistant professor of Human Centered Design and Engineering."We found that reading is just a small part of what students are doing. And when we realize how dynamic and complicated a process this is, it kind of redefines what it means to design an e-reader."

Some of the other schools participating in the pilot project conducted shorter studies, generally looking at the e-reader's potential benefits and drawbacks for course use. The UW study looked more broadly at how students did their academic reading, following both those who incorporated the e-reader into their routines and those who did not.

"We were not trying to evaluate the device, per se, but wanted to think long term, really looking to the future of e-readers, what are students trying to do, how can we support that," Lee said.

The researchers interviewed 39 first-year graduate students in the UW's Department of Computer Science& Engineering, 7 women and 32 men, ranging from 21 to 53 years old.

By spring quarter of 2010, seven months into the study, less than 40 percent of the students were regularly doing their academic reading on the Kindle DX. Reasons included the device's lack of support for taking notes and difficulty in looking up references. (Amazon Corp., which makes the Kindle DX, has since improved some of these features.)

UW researchers continued to interview all the students over the nine-month period to find out more about their reading habits, with or without the e-reader. They found:

• Students did most of the reading in fixed locations: 47 percent of reading was at home, 25 percent at school, 17 percent on a bus and 11 percent in a coffee shop or office.
• The Kindle DX was more likely to replace students' paper-based reading than their computer-based reading.
• Of the students who continued to use the device, some read near a computer so they could look up references or do other tasks that were easier to do on a computer. Others tucked a sheet of paper into the case so they could write notes.
• With paper, three quarters of students marked up texts as they read. This included highlighting key passages, underlining, drawing pictures and writing notes in margins.
• A drawback of the Kindle DX was the difficulty of switching between reading techniques, such as skimming an article's illustrations or references just before reading the complete text. Students frequently made such switches as they read course material.
• The digital text also disrupted a technique called cognitive mapping, in which readers used physical cues such as the location on the page and the position in the book to go back and find a section of text or even to help retain and recall the information they had read.

Lee predicts that over time software will help address some of these issues. She even envisions niche software that could support reading styles specific to certain disciplines.

"You can imagine that a historian going through illuminated texts is going to have very different navigation needs than someone who is comparing algorithms," Lee said.

It's likely that desktop computers, laptops, tablet computers and yes, even paper, will play a role in academic reading's future. But the authors say e-readers will also find their place. Thayer imagines the situation will be similar to today's music industry, where mp3s, CDs and LPs all coexist in music-lovers' listening habits.

"E-readers are not where they need to be in order to support academic reading," Lee concludes. But asked when e-readers will reach that point, she predicts:"It's going to be sooner than we think."

Other co-authors are Linda Hwang, Heidi Sales, Pausali Sen and Ninad Dalal of the UW.

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