Complex+systems+and+statistical+physics+lab
-
Dong Ah Newspaper Publish '100 Koreans who will Represent Korea in 10 years'
The 2011 list of ‘100 Koreans who will Represent Korea in 10 years’ published by Dong Ah Newspaper includes people of varying ages, vocation, and gender.
In terms of University Professors, five professors from each of KAIST and SNU (Seoul National University) were selected. Especially Professor Charles Ahn received the most votes due to his world class talent, potential, and dedication.
Professor Kim Sang Wook of the Department of Materials Science and Engineering is the world leading expert in the field of ‘Atom Construction Nanotechnology’ which deals with using macromolecules, carbon nanotubes, and grapheme to form various structures. His work on ‘low cost, large area nano patterning technology’ is expected to overcome the limits of nano treatment processes and its application in semi-conductors or displays carries great promise.
Professor Kim Eun Sung of the Department of Physics discovered a new quantum behavior, supersolidity, in a low temperature, solid Helium for the first time in the world and is the leading scientist that leads the mechanics behind such a phenomenon. Professor Kim is leading the field of supersolidity through his works on hidden phase in a low temperature solid Helium, the understanding the role of crystalline faults in the supersolidity phenomenon, and the destruction of the supersolid’s macromolecular phenomenon through spinning solids.
Professor Charles Ahn of the Graduate School of Innovation and Technology Management has been working as the developer of the V3 series (an anti-computer virus Vaccine Program) since 1988. He established the ‘Charles Ahn Research Center’ in 1995 and his solid and practical management style won him rave reviews. Professor Ahn was appointed as the Professor of the Graduate School of Innovation and Technology Management and has been teaching entrepreneurial perspective and Technology Management.
Professor Lee Sang Yeop of the Department of Biology and Chemical Engineering developed world’s most efficient production method of succinic acid, developed high efficiency, tailored, culture for the production of key amino acids, Valine and Threonine, developed the production culture off bio-buthanol which is superior to bio-ethanol, and is widely known as one of the leaders in the field of metabolic engineering.
Professor Jeong Ha Woong of the Department of Physics is being regarded as world leader in the field of Complex System Network Sciences. He implemented Statistical Physics to Complex Systems and also used the concept of ‘Networks’ and published 80 papers, including 5 which were published in Nature Magazine.
2011.04.30 View 12481 -
Scaling Laws between Population and Facility Densities Found
A research team led by Prof. Ha-Woong Jeong of the Department of Physics, KAIST, has found a positive correlation between facilities and population densities, university authorities said on Tuesday (Sept. 2). The research was conducted in the cooperation with a research team of Prof. Beom-Jun Kim at Sungkyunkwan University.
The researchers investigated the ideal relation between the population and the facilities within the framework of an economic mechanism governing microdynamics.
In previous studies based on the global optimization of facility positions in minimizing the overall travel distance between people and facilities, the relation between population and facilities should follow a simple law. The new empirical analysis, however, determined that the law is not a fixed value but spreads in a broad range depending on facility types.
To explain this discrepancy, the researchers proposed a model based on economic mechanism that mimics the competitive balance between the profit of the facilities and the social opportunity cost for population.
The results were published in the Proceedings of the National Academy of Sciences of the United States on Aug. 25.
2009.09.04 View 11952
-
KAIST Professor Finds Paradox in Human Behaviors on Road
-Strange as it might seem, closing roads can cut delays
A new route opened to ease traffic jam, but commuting time has not been reduced.Conversely, motorists reached their destinations in shorter times after a big street was closed. These paradoxical phenomena are the result of human selfishness, according to recent findings of a research team led by a KAIST physics professor.
Prof. Ha-Woong Jeong, 40, at the Department of Physics, conducted a joint research with a team from Santa Fe Institute of the U.S. to analyze the behaviors of drivers in Boston, New York and London. Their study found that when individual drivers, fed with traffic information via various kinds of media, try to choose the quickest route, it can cause delays for others and even worsen congestion.
Prof. Jeong and his group"s study will be published in the Sept. 18 edition of the authoritative Physical Review Letters. The London-based Economist magazine introduced Prof. Jeong"s finding in its latest edition.
Prof. Jeong, a pioneer in the study of "complex system," has published more than 70 research papers in the world"s leading science journals, including Nature, PNAS and Physical Review Letters. "Initially, my study was to reduce annoyance from traffic jam during rush hours," Prof. Jeong said. "Ultimately, it is purposed to eliminate inefficiency located in various corners of social activities, with the help of the network science."
The Economist article read (in part):
"...when individual drivers each try to choose the quickest route it can cause delays for others and even increase hold-ups in the entire road network.
"The physicists give a simplified example of how this can happen: trying to reach a destination either by using a short but narrow bridge or a longer but wide motorway. In their hypothetical case, the combined travel time of all the drivers is minimized if half use the bridge and half the motorway. But that is not what happens. Some drivers will switch to the bridge to shorten their commute, but as the traffic builds up there the motorway starts to look like a better bet, so some switch back. Eventually the traffic flow on the two routes settles into what game theory calls a Nash equilibrium, named after John Nash, the mathematician who described it. This is the point where no individual driver could arrive any faster by switching routes.
"The researchers looked at how this equilibrium could arise if travelling across Boston from Harvard Square to Boston Common. They analysed 246 different links in the road network that could be used for the journey and calculated traffic flows at different volumes to produce what they call a “price of anarchy” (POA). This is the ratio of the total cost of the Nash equilibrium to the total cost of an optimal traffic flow directed by an omniscient traffic controller. In Boston they found that at high traffic levels drivers face a POA which results in journey times 30% longer than if motorists were co-ordinated into an optimal traffic flow. Much the same thing was found in London (a POA of up to 24% for journeys between Borough and Farringdon Underground stations) and New York (a POA of up to 28% from Washington Market Park to Queens Midtown Tunnel).
"Modifying the road network could reduce delays. And contrary to popular belief, a simple way to do that might be to close certain roads. This is known as Braess’s paradox, after another mathematician, Dietrich Braess, who found that adding extra capacity to a network can sometimes reduce its overall efficiency.
"In Boston the group looked to see if the paradox could be created by closing any of the 246 links. In 240 cases their analysis showed that a closure increased traffic problems. But closing any one of the remaining six streets reduced the POA of the new Nash equilibrium. Much the same thing was found in London and New York. More work needs to be done to understand these effects, say the researchers. But even so, planners should note that there is now evidence that even a well intentioned new road may make traffic jams worse."
2008.09.18 View 13261