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Interactions Features KAIST's Human-Computer Interaction Lab
Interactions, a bi-monthly magazine published by the Association for Computing Machinery (ACM), the largest educational and scientific computing society in the world, featured an article introducing Human-Computer Interaction (HCI) Lab at KAIST in the March/April 2015 issue (http://interactions.acm.org/archive/toc/march-april-2015).
Established in 2002, the HCI Lab (http://hcil.kaist.ac.kr/) is run by Professor Geehyuk Lee of the Computer Science Department at KAIST. The lab conducts various research projects to improve the design and operation of physical user interfaces and develops new interaction techniques for new types of computers. For the article, see the link below:
ACM Interactions, March and April 2015
Day in the Lab: Human-Computer Interaction Lab @ KAIST
http://interactions.acm.org/archive/view/march-april-2015/human-computer-interaction-lab-kaist
2015.03.02 View 10731 -
The Real Time Observation of the Birth of a Molecule
From right to left: Dr. Kyung-Hwan Kim, Professor Hyotcherl Lhee, and Jong-Gu Kim, a Ph.D. candidate
Professor Hyotcherl Lhee of the Department of Chemistry at KAIST and Japanese research teams jointly published their research results showing that they have succeeded in the direct observation of how atoms form a molecule in the online issue of Nature on February 19, 2015.
The researchers used water in which gold atoms ([Au(CN) 2- ]) are dissolved and fired X-ray pulses over the specimen in femtosecond timescales to study chemical reactions taking place among the gold atoms. They were able to examine in real time the instant process of how gold atoms bond together to become a molecule, to a trimer or tetramer state.
This direct viewing of the formation of a gold trimer complex ([Au(CN) 2- ] 3 ) will provide an opportunity to understand complex chemical and biological systems.
For details, please see the following press release that was distributed by the High Energy Accelerator Research Organization, KEK, in Japan:
Direct Observation of Bond Formations
February 18, 2015
A collaboration between researchers from KEK, the Institute for Basic Science (IBS), the Korea Advanced Institute of Science and Technology (KAIST), RIKEN, and the Japan Synchrotron Radiation Research Institute (JASRI) used the SACLA X-ray free electron laser (XFEL) facility for a real time visualization of the birth of a molecular that occurs via photoinduced formation of a chemical bonds. This achievement was published in the online version of the scientific journal “Nature” (published on 19 February 2015).
Direct “observation” of the bond making, through a chemical reaction, has been longstanding dream for chemists. However, the distance between atoms is very small, at about 100 picometer, and the bonding is completed very quickly, taking less than one picosecond (ps). Hence, previously, one could only imagine the bond formation between atoms while looking at the chemical reaction progressing in the test-tube.
In this study, the research group focused on the process of photoinduced bond formation between gold (Au) ions dissolved in water. In the ground state (S 0 state in Fig. 1) Au ions that are weakly bound to each other by an electron affinity and aligned in a bent geometry. Upon a photoexcitation, the S 0 state rapidly converts into an excited (S 1 state in Fig. 1) state where Au-Au covalent bonds are formed among Au ions aligned in a linear geometry. Subsequently, the S 1 state transforms to a triplet state (T 1 state in Fig. 1) in 1.6 ps while accompanying further contraction of Au-Au bonds by 0.1 Å. Later, the T 1 state of the trimer converts to a tetramer (tetramer state in Fig. 1) on nanosecond time scale. Finally, the Au ions returned to their original loosely interacting bent structure.
In this research, the direct observation of a very fast chemical reaction, induced by the photo-excitation, was succeeded (Fig. 2, 3). Therefore, this method is expected to be a fundamental technology for understanding the light energy conversion reaction. The research group is actively working to apply this method to the development of viable renewable energy resources, such as a photocatalysts for artificial photosynthesis using sunlight.
This research was supported by the X-ray Free Electron Laser Priority Strategy Program of the MEXT, PRESTO of the JST, and the the Innovative Areas "Artificial Photosynthesis (AnApple)" grant from the Japan Society for the Promotion of Science (JSPS).
Publication: Nature , 518 (19 February 2015)
Title: Direct observation of bond formation in solution with femtosecond X-ray scattering
Authors: K. H. Kim 1 , J. G. Kim 1 , S. Nozawa 1 , T. Sato 1 , K. Y. Oang, T. W. Kim, H. Ki, J. Jo, S. Park, C. Song, T. Sato, K. Ogawa, T. Togashi, K. Tono, M. Yabashi, T. Ishikawa, J. Kim, R. Ryoo, J. Kim, H. Ihee, S. Adachi. ※ 1: These authors contributed equally to the work.
DOI: 10.1038/nature14163
Figure 1. Structure of a gold cyano trimer complex (Au(CN) 2 - ) 3 .
Figure 2. Observed changes in the molecular structure of the gold complex
Figure 3. Schematic view of the research of photo-chemical reactions by the molecular movie
2015.02.27 View 12952 -
KAIST Develops Subminiature, Power-Efficient Air Pollution Sensing Probe
Professor Inkyu Park and his research team from the Department of Mechanical Engineering at KAIST have developed a subminiature, power-efficient air-pollution sensing probe that can be applied to mobile devices. Their research findings were published online in the January 30th issue of Scientific Reports.
As air pollution has increased, people have taken greater interest in health care. The developed technology could allow people to measure independently the air pollution level of their surrounding environments.
Previous instruments used to measure air pollution levels were bulky and consumed a lot of power. They also often produced inaccurate results when measuring air pollution in which different toxic gases were mixed. These problems could not be resolved with existing semiconductor manufacturing process.
Using local temperature field control technology, Professor Park’s team succeeded in integrating multiple heterogeneous nanomaterials and fitting them onto a small, low-power electronic chip. This microheating sensor can heat microscale regions through local hydrothermal synthesis. Because it requires a miniscale amount of nanomaterials to manufacture, the sensor is most suitable for mobile devices.
Professor Park said, “Our research will contribute to the development of convergence technology in such field as air pollution sensing probes, biosensors, electronic devices, and displays.”
The team's research was supported by the Ministry of Education and the Ministry of Science, ICT and Future Planning, Republic of Korea.
Figure 1 – The Concept of Multiple Nanomaterial Device and Numerical Simulation Results of Precursor Solutions
Figure 2 - Multiple Nanomaterial Manufactured in a Microscale Region
2015.02.27 View 11174 -
KAIST Team Wins International Hacking Competition, "SECCON CTF 2014"
KAIST’s white hacker team, “TOFEL Beginner,” secured the first place in an international hacking competition, SECCON CTF 2014. SECCON is an international hacking competition which has operated for more than 20 years. It uses the Capture the Flag (CTF) method. Last year’s competition was held in Tokyo on December 7, 2014.
The TOFEL Beginner team consisted of two KAIST graduate students and two researchers from a private security company based in Korea: In-Soo Yoon of Computer Science, Eun-Soo Kim of the Graduate School of Information Security (GSIS), and Jong-Ho Lee and Jung-Hoon Lee of Raon Secure.
Of 4,186 competitors, 24 teams made it to the finals. The TOFEL Beginner took the lead with 4,506 points compared with HITCON (3,112 points) of Taiwan and PPP (2,858 points) of the USA.
With this victory, the KAIST team qualified to participate in the most renowned international hacking competition, the DEF CON Hacking Conference in 2015.
Professor Yongdae Kim of the Electrical Engineering Department at KAIST, who advised the TOEFL Beginner team, said, “Our members have achieved an outstanding result. By taking advantage of this opportunity, KAIST will continue to offer the best programs in information security in Korea and hopefully beyond.”
2015.02.24 View 10466 -
Professor Kwang-Hyun Cho Recognzied by "Scientist of the Month" Award
Professor Kwang-Hyun Cho of KAIST’s Department of Bio and Brain Engineering received the “Scientist of the Month” award in February 2015 from the Ministry of Science, ICT, and Future Planning of the Republic of Korea and the National Research Foundation of Korea. The award was in recognition of Professor Cho’s contribution to the advanced technique of controlling the death of cancer cells based on systems biology, a convergence research in information technology (IT) and biotechnology.
Professor Cho has published around 140 articles in international journals, including 34 papers in renowned science journals such as Nature, Science, and Cell in the past three years. His work also includes systems biology textbooks and many entries in international academic encyclopaedia.
His field, systems biology, is a new biological research paradigm that identifies and controls the fundamental principles of organisms on a systems level.
A well-known tumour suppressor protein, p53, is known to suppress abnormal cell growth and promote apoptosis of can cells, and thus was a focus of research by many scientists, but its effect has been insignificant and brought many side effects. This was due to the complex function of p53 that controls various positive and negative feedbacks. Therefore, there was a limit to understanding the protein with the existing biological approach.
However, Professor Cho found the kinetic change and function of p53 via a systems biology approach. By applying IT technology to complex biological networks, he also identified the response to stress and the survival and death signal transduction pathways of cardiomyocytes and developed new control methods for cancer cells.
Professor Cho said, “This award served as a momentum to turn over a new leaf.” He added, “I hope convergence research such as my field will bring more innovative ideas on the boundaries of academia.”
2015.02.09 View 13554 -
News Article: Flexible, High-performance Nonvolatile Memory Developed with SONOS Technology
Professor Yang-Kyu Choi of KAIST’s Department of Electrical Engineering and his team presented a research paper entitled “Flexible High-performance Nonvolatile Memory by Transferring GAA Silicon Nanowire SONOS onto a Plastic Substrate” at the conference of the International Electron Devices Meeting that took place on December 15-17, 2014 in San Francisco.
The Electronic Engineering Journal (http://www.eejournal.com/) recently posted an article on the paper:
Electronic Engineering Journal, February 2, 2015
“A Flat-Earth Memory”
Another Way to Make the Brittle Flexible
http://www.techfocusmedia.net/archives/articles/20150202-flexiblegaa/?printView=true
2015.02.03 View 8006 -
KAIST Develops a Method to Transfer Graphene by Stamping
Professor Sung-Yool Choi’s research team from KAIST's Department of Electrical Engineering has developed a technique that can produce a single-layer graphene from a metal etching. Through this, transferring a graphene layer onto a circuit board can be done as easily as stamping a seal on paper.
The research findings were published in the January 14th issue of Small as the lead article.
This technology will allow different types of wafer transfer methods such as transfer onto a surface of a device or a curved surface, and large surface transfer onto a 4 inch wafer. It will be applied in the field of wearable smart gadgets through commercialization of graphene electronic devices.
The traditional method used to transfer graphene onto a circuit board is a wet transfer. However, it has some drawbacks as the graphene layer can be damaged or contaminated during the transfer process from residue from the metal etching. This may affect the electrical properties of the transferred graphene.
After a graphene growth substrate formed on a catalytic metal substrate is pretreated in an aqueous poly vinyl alcohol (PVA) solution, a PVA film forms on the pretreated substrate. The substrate and the graphene layers bond strongly. The graphene is lifted from the growth substrate by means of an elastomeric stamp.
The delaminated graphene layer is isolated state from the elastomeric stamp and thus can be freely transferred onto a circuit board. As the catalytic metal substrate can be reused and does not contain harmful chemical substances, such transfer method is very eco-friendly.
Professor Choi said, “As the new graphene transfer method has a wide range of applications and allows a large surface transfer, it will contribute to the commercialization of graphene electronic devices.” He added that “because this technique has a high degree of freedom in transfer process, it has a variety of usages for graphene and 2 dimensional nano-devices.”
This research was sponsored by the Ministry of Science, ICT and Future Planning, the Republic of Korea.
Figure 1. Cover photo of the journal Small which illustrates the research findings
Figure 2. Above view of Graphene layer transferred through the new method
Figure 3. Large surface transfer of Graphene
2015.01.23 View 11657 -
KAIST Announces the Recipients of Distinguished Alumni Awards
The KAIST Alumni Association (KAA) announced four “Proud KAIST Alumni” awards recipients for the year 2014: Sung-Wook Park, the Chief Executive Officer and President of SK Hynix; Seung Ho Shin, the President of Kangwon National University; Kew-Ho Lee, the President of the Korea Research Institute of Chemical Technology; and Mun-Kee Choi, the former Minister of Science, ICT and Future Planning of the Republic of Korea. The award ceremony took place during the 2015 KAA’s New Year's ceremony on January 17, 2015 at the Palace Hotel in Seoul.
Sung-Wook Park (M.S. ’82 and Ph.D. ’88, Department of Materials Science and Engineering), the Chief Executive Officer and President of SK Hynix, has worked as an expert in the field of memory semi-conductors for the past 30 years. He developed innovative technology and improved production efficiency, enabling the Korean semi-conductor industry to become a global leader.
Seung Ho Shin (M.S. ’79 and Ph.D. ’87, Department of Physics), the President of Kangwon National University (KNU), worked in the field of optical information processing, producing excellent research achievements and teaching the next generation of scientists. As the president of KNU, he has set an exemplary leadership in higher education.
Kew-Ho Lee (M.S. ’75, Department of Chemistry), the President of the Korea Research Institute of Chemical Technology, pioneered the field of separation film production which contributed greatly to Korean technological developments. He led several domestic and international societies to facilitate dynamic exchanges between industry and academia and with the international community.
Mun-Kee Choi (M.S. ’76, Department of Industrial and Systems Engineering), the former Minister of Science, ICT and Future Planning, the Republic of Korea, is a great contributor to the information and communications technology in Korea, working as a leader in the field of broadband integrated service digital network. He is also an educator for gifted students in science and technology, and a manager of the Electronics and Telecommunications Research Institute.
The Alumni Association established the “Proud KAIST Alumni Awards” in 1992 to recognize its alumni’s outstanding contributions to Korea and KAIST.
Pictured from left to right, Sung-Wook Park (the Chief Executive Officer and President of SK Hynix), Seung Ho Shin (the President of Kangwon National University), Kew-Ho Lee (the President of the Korea Research Institute of Chemical Technology), and Mun-Kee Choi (the former Minister of Science, ICT and Future Planning)
2015.01.19 View 15330 -
Hierarchically-Porous Polymers with Fast Absorption
KAIST's Professor Myungeun Seo and his research team from the Graduate School of Nanoscience and Technology has developed a method to form micropores of less than 2 nanometers within porous polymers where 10 nanometers long mesopores connect like a net. The advantage of the porous polymers is fast absorption of molecules.
Porous polymers with micropores of less than 2 nanometers, like a zeolite, have a large surface area. They are used as a means to store hydrogen-based molecules or as a catalytic support that can be used as a surface to convert a material into a desired form. However, because the size of the pores in its path was too small for the molecules, it took a long time to spread into the pores and reach the surface.
To reach the surface efficiently, a lung cell or the vein of a leaf has a structure wherein the pores are subdivided into different sizes so that the molecule can spread throughout the organ. A technology that can create not only micropores but also bigger pores was necessary in order to create such structure.
The research team solved the issue by implementing a "self-assembly" of block polymers to easily form a net-like nanostructure from mesopores of 10 nanometers.
The team created hierarchically-porous polymers consisting of two different types of pores by using a hypercrosslinking reaction along with the "self-assembly" method. The reaction creates micropores within the chain after the polymer chain is confined by a chemical bond.
This porous polymer has micropores that are smaller than 2 nanometers on the walls of mesopores while 10 nanometers long mesopores forming 3-dimensional net structures. Because of the "self-assembly" method, the size of mesopores can be adjusted within the range of 6 to 15 nanometers.
This is the first case where a porous polymer has both well-defined mesopores and micropores. The research team verified the effect of hierarchically-porous structures on absorption of molecules by confirming that the porous polymer had faster absorption speeds than a polymer consisting only of micropores.
Professor Seo said, “The study has found a simple way to create different sizes of pores within a polymer.” He expected that the hierarchically-porous polymers can be used as a catalytic support in which fast diffusion of molecules is essential, or for molecule collection.
The research was sponsored by National Research Foundation of Korea and published online in the Journal of the American Chemical Society.
Figure 1 – Net-like Structure of Hierarchically-Porous Polymers with Mesopores and Micropores on the walls of Mesopores.
Figure 2 - Hierarchically-Porous Polymers
Figure 3 – Comparison of Porous-Polymers consisting of Mesopores only (left), and Mesopores and Micropores (right)
2015.01.13 View 9073 -
Professor Eunjoon Kim Is KAIST's Person of the Year 2014
KAIST announced that it has named Chair Professor Eunjoon Kim of the Department of Biological Sciences as its “Person of the Year 2014.” The award ceremony took place at the auditorium on campus on January 5, 2014.
Established in 2001, the award has been presented to a KAIST faculty member who has made great achievements in research and education, thereby contributing to the advancement of KAIST.
Professor Kim was the first to identify the mechanism of synapse formation between neurons during his post-doctoral program at Harvard Medical School in 1995. The research was published in Nature.
In 2011, Professor Kim discovered that the lack of protein GIT1, a neuronal synapse in the brain, caused ADHD (Attention Deficit Hyperactivity Disorder). He is widely recognized for his work concerning synapse proteins and brain disease related research that set the foundation for future medical developments.
In his award speech, Professor Kim said, “Whenever a research finding concerning a new drug therapy or research is published, I receive many inquiries from the parents of children with ADHD or autism. As a scientist, I would like to focus my research ultimately to help those in pain, rather than just pursuing research excellence or reputation.”
2015.01.06 View 10870 -
A Key Signal Transduction Pathway Switch in Cardiomyocyte Identified
A KAIST research team has identified the fundamental principle in deciding the fate of cardiomyocyte or heart muscle cells. They have determined that it depends on the degree of stimulus in β-adrenergic receptor signal transduction pathway in the cardiomyocyte to control cells' survival or death. The findings, the team hopes, can be used to treat various heart diseases including heart failure.
The research was led by KAIST Department of Bio and Brain Engineering Chair Professor Kwang-Hyun Cho and conducted by Dr. Sung-Young Shin (lead author) and Ph.D. candidates Ho-Sung Lee and Joon-Hyuk Kang. The research was conducted jointly with GIST (Gwangju Institute of Science and Technology) Department of Biological Sciences Professor Do-Han Kim’s team. The research was supported by the Ministry of Science, ICT and Future Planning, Republic of Korea, and the National Research Foundation of Korea. The paper was published in Nature Communications on December 17, 2014 with the title, “The switching role of β-adrenergic receptor signalling in cell survival or death decision of cardiomyocytes.”
The β-adrenergic receptor signal transduction pathway can promote cell survival (mediated by β2 receptors), but also can result in cell death by inducing toxin (mediated by β1 receptors) that leads to various heart diseases including heart failure. Past attempts to identify the fundamental principle in the fate determining process of cardiomyocyte based on β-adrenergic receptor signalling concluded without much success.
The β-adrenergic receptor is a type of protein on the cell membrane of cardiomyocyte (heart muscle cell) that when stimulated by neurohormones such as epinephrine or norepinephrine would transduce signals making the cardiomyocyte contract faster and stronger.
The research team used large-scale computer simulation analysis and systems biology to identify ERK* and ICER** signal transduction pathways mediated by a feed-forward circuit as a key molecular switch that decides between cell survival and death.
Weak β-adrenergic receptor stimulations activate ERK signal transduction pathway, increasing Bcl-2*** protein expression to promote cardiomyocyte survival. On the other hand, strong β-adrenergic receptor stimulations activate ICER signal transduction pathway, reducing Bcl-2 protein expression to promote cardiomyocyte death.
Researchers used a systems biology approach to identify the mechanism of B-blocker****, a common drug prescribed for heart failure. When cardiomyocyte is treated with β1 inhibitor, strong stimulation on β-adrenergic receptor increases Bcl-2 expression, improving the chance of cardiomyocyte survival, a cell protection effect.
Professor Kwang-Hyun Cho said, “This research used systems biology, an integrated, convergence research of IT (information technology) and BT (biotechnology), to successfully identify the mechanism in deciding the fate of cardiomyocytes based on the β-adrenergic receptor signal transduction pathway for the first time. I am hopeful that this research will enable the control of cardiomyocyte survival and death to treat various heart diseases including heart failure.”
Professor Cho’s team was the first to pioneer a new field of systems biology, especially concerning the complex signal transduction network involved in diseases. Their research is focused on modelling, analyzing simulations, and experimentally proving signal pathways. Professor Cho has published 140 articles in international journals including Cell, Science, and Nature.
* ERK (Extracellular signal-regulated kinases): Signal transduction molecule involved in cell survival
** ICER (Inducible cAMP early repressor): Signal transduction molecule involved in cell death
*** Bcl-2 (B-cell lymphoma 2): Key signal transduction molecule involved in promotion of cell survival
**** β-blocker: Drug that acts as β-adrenergic receptor inhibitor known to slow the progression of heart failure, hence used most commonly in medicine.
Picture: A schematic diagram for the β-AR signalling network
2015.01.05 View 14135 -
Broadband and Ultrathin Polarization Manipulators Developed
Professor Bumki Min from the Department of Mechanical Engineering at KAIST has developed a technology that can manipulate a polarized light in broadband operation with the use of a metamaterial.
It is expected that this technology will lead to the development of broadband optical devices that can be applied to broadband communication and display.
When an object or its structure is analyzed by using a polarized light such as a laser, the results are generally affected by the polarized state of the light. Therefore, in an optics laboratory, the light is polarized by various methods.
In such cases, researchers employ wave plates or photoactive materials. However, the performance of these devices depend vastly on wavelength, and so they are not suitable to be used as a polarizer, especially in broadband.
There were many attempts to make artificial materials that are very photoactive by using metamaterials which have a strong resonance. Nonetheless, because the materials had an unavoidable dispersion in the resonance frequency, they were not adequate for broadband operation.
Professor Min’s research team arranged and connected helical metamaterials that are smaller than the wavelength of light. They verified theoretically and experimentally that polarized light can be constantly rotated regardless of the wavelength by super-thin materials that have thickness less than one-tenth of the wavelength of the light. The experiment which confirmed the theory was conducted in the microwave band.
Broadband polarized rotational 3D metamaterials were found to rotate the polarized microwave within the range of 0.1 GHz to 40 GHz by 45 degrees regardless of its frequency. This nondispersive property is quite unnatural because it is difficult to find a material that does not change in a wide band.
In addition, the research team materialized the broadband nondispersive polarized rotational property by designing the metamaterial in a way that it has chirality, which determines the number of rotations proportional to the wavelength.
Professor Min said, “As the technology is able to manipulate ultrathin polarization of light in broadband, it will lead to the creation of ultra-shallow broadband optical devices.”
Sponsored by the Ministry of Science, ICT and Future Planning of the Republic of Korea and the National Research Foundation of Korea, this research was led by a PhD candidate, Hyun-Sung Park, under the guidance of Professor Min. The research findings were published online in the November 17th issue of Nature Communications.
Figure 1 – Broadband and Ultrathin Polarization Manipulators Produced by 3D Printer
Figure 2 – Concept of Broadband and Ultrathin Polarization Manipulators
2014.12.03 View 12123