-
Dr. Sung-Chul Shin Selected 16th President of KAIST
(President Sung-Chul Shin)
The KAIST Board of Trustees elected Professor Sung-Chul Shin of the Department of Physics the 16th president of KAIST on February 21. Professor Shin succeeds President Sung-Mo Kang whose four-year term will end on February 23. He is the first KAIST alumnus to serve as its president.
The Board of Trustees announced, “We believe that Professor Shin’s scientific achievement, outstanding leadership, and clear vision will serve KAIST faculty, students, and staff very well. He will be the best person to help KAIST leap forward in the four years ahead.”
The newly-elected president said, “I am humbled and honored to have been elected to lead such a prestigious institute of Korea. Aiming to be one of the top ten global universities, KAIST will continue to innovate its systems.” Previously, Dr. Shin led the Daegu Gyeongbuk Institute of Science and Technology (DGIST) for six years as president since 2011.
Professor Shin joined the KAIST faculty in 1989. He graduated from Seoul National University and then earned his MS degree in condensed matter physics at KAIST in 1977. After earning his Ph.D. in material physics at Northwestern University in 1984, he worked at Eastman Kodak Research Labs as a senior research scientist for five years.
Before heading to DGIST, President Shin held key administrative positions at KAIST from the early 1990s including dean of planning, dean of the international office, and vice-dean of student affairs. During President Robert Laughlin’s tenure, the first foreign president at KAIST, he served as vice-president for two years from 2004. He also served on the Presidential Advisory Council on Science and Technology of the Korean government as vice chairperson from 2015 to 2016.
A renowned scholar in the field of nanoscience, President Shin’s research focuses on the artificial synthesis and characterization of nonmagnetic materials, magnetic anisotropy, and magneto-optical phenomena. He leads the Laboratory for Nanospinics of Spintronic Materials at KAIST and has published in 290 journals while holding 37 patents.
A fellow in the American Physical Society (APS) since 2008, he was the president of the Korean Physical Society from 2011 to 2012. He has been on the editorial board of J. Magnetism and Magnetic Materials from 2009 and was the first Korean recipient of the Asian Union of Magnetics Societies (AUMS) Award, which recognizes outstanding scientists in the field of magnetics.
President Shin envisions making KAIST’s research and education more competitive through continuing innovation. His innovation efforts will extend to the five key areas of education, research, technology commercialization, globalization, and future planning.
Among his priorities, he emphasizes multidisciplinary studies and leadership training for students. He plans to focus on undeclared major courses for undergraduates to help them expand their experience and exposure to diverse disciplines. This approach will help create well-rounded engineers, scientists, and entrepreneurs by enabling them to develop skills while leveraging a strong connection to the arts, humanities, and social sciences.
To better respond to Industry 4.0, which calls for convergence studies and collaborative work, he proposed establishing a ‘Convergence Innovation System’ by strategically selecting 10 flagship convergence research groups. In order to accelerate the technology commercialization and ecosystem of start-ups, he will strengthen entrepreneurship education, making it a prerequisite requirement for students. President Shin said he will spare no effort to incubate and spin-off ventures in which KAIST technology is being transferred. For globalization efforts, he plans to increase the ratio of foreign faculty from 9 percent to 15 percent, while doubling the current foreign student enrollment ratio of 5 percent. For future strategic innovation, he will implement a long-term innovation strategic plan dubbed ‘Vision 2031.’
2017.02.22 View 9242 -
Controlling Turtle Motion with Human Thought
KAIST researchers have developed a technology that can remotely control an animal’s movement with human thought.
In the 2009 blockbuster “Avatar,” a human remotely controls the body of an alien. It does so by injecting human intelligence into a remotely located, biological body. Although still in the realm of science fiction, researchers are nevertheless developing so-called ‘brain-computer interfaces’ (BCIs) following recent advances in electronics and computing. These technologies can ‘read’ and use human thought to control machines, for example, humanoid robots.
New research has demonstrated the possibility of combining a BCI with a device that transmits information from a computer to a brain, or known as a ‘computer-to-brain interface’ (CBI). The combination of these devices could be used to establish a functional link between the brains of different species. Now, researchers from the Korea Advanced Institute of Science and Technology (KAIST) have developed a human-turtle interaction system in which a signal originating from a human brain can affect where a turtle moves.
Unlike previous research that has tried to control animal movement by applying invasive methods, most notably in insects, Professors Phill-Seung Lee of the Mechanical Engineering Department and Sungho Jo of the Computing School propose a conceptual system that can guide an animal’s moving path by controlling its instinctive escape behavior. They chose a turtle because of its cognitive abilities as well as its ability to distinguish different wavelengths of light. Specifically, turtles can recognize a white light source as an open space and so move toward it. They also show specific avoidance behavior to things that might obstruct their view. Turtles also move toward and away from obstacles in their environment in a predictable manner. It was this instinctive, predictable behavior that the researchers induced using the BCI.
The entire human-turtle setup is as follows: A head-mounted display (HMD) is combined with a BCI to immerse the human user in the turtle’s environment. The human operator wears the BCI-HMD system, while the turtle has a 'cyborg system'—consisting of a camera, Wi-Fi transceiver, computer control module, and battery—all mounted on the turtle’s upper shell. Also included on the turtle’s shell is a black semi-cylinder with a slit, which forms the ‘stimulation device.’ This can be turned ±36 degrees via the BCI.
The entire process works like this: the human operator receives images from the camera mounted on the turtle. These real-time video images allow the human operator to decide where the turtle should move. The human provides thought commands that are recognized by the wearable BCI system as electroencephalography (EEG) signals. The BCI can distinguish between three mental states: left, right, and idle. The left and right commands activate the turtle’s stimulation device via Wi-Fi, turning it so that it obstructs the turtle’s view. This invokes its natural instinct to move toward light and change its direction. Finally, the human acquires updated visual feedback from the camera mounted on the shell and in this way continues to remotely navigate the turtle’s trajectory.
The research demonstrates that the animal guiding scheme via BCI can be used in a variety of environments with turtles moving indoors and outdoors on many different surfaces, like gravel and grass, and tackling a range of obstacles, such as shallow water and trees. This technology could be developed to integrate positioning systems and improved augmented and virtual reality techniques, enabling various applications, including devices for military reconnaissance and surveillance.
***
Reference: “Remote Navigation of Turtle by Controlling Instinct Behavior via Human Brain-computer Interface,” Journal of Bionic Engineering, July 2016 (DOI: 10.1016/S1672-6529(16)60322-0)
Depiction of Cyborg System
A human controller influences the turtle’s escape behavior by sending left and right signals via Wi-Fi to a control system on the back of the turtle.
2017.02.21 View 13731 -
The 2016 Research Highlights
KAIST has selected the ten most outstanding projects of 2016 conducted by its faculty and researchers. This selection embodies the KAIST research portfolios that translate their discoveries into meaningful and measurable impact toward a better world. All of them demonstrate exceptional creativity, which open new research paths for each field in its novelty, innovation, and impact.
The following list has been reviewed by a committee of faculty peers headed by Associate Vice President for Research. Following are the 2016 KAIST research highlights:
□ Commercialization of 3D Holographic Microscopy
By YongKeun Park of the Department of Physics
Professor YongKeun Park and his colleagues develop a powerful technique to measure 3D images of live cells without labeling agents. This technique, called 3D holographic microscopy or holotomography, will open a new avenue for the study of cell biology and its applications in medical diagnosis. This research also led to the founding of a start-up company Tomocube Inc. and the successful commercialization of the technique.
Professor Park and his research team developed a solution based on digital holography technology used to visualize 3D refractive index tomograms of live cells without staining. This allowed the real-time observation of biological cells in 2D, 3D, and 4D without the use of labeling agents. Conventional techniques for 3D cell imaging requires the use of labeling agents such as fluorescence dyes and proteins, which prevent from investigating the physiology of intact untreated cells. In particular, label-free imaging capability becomes more important in several emerging fields such as stem cell research and immunotherapy.
The team employs the concept of 3D digital holography to achieve the optical measurements of 3D refractive index tomograms of live cells and tissues. Also, a digital micromirror device (DMD), which has been used for DLPTM projectors, was utilized to steer a laser beam for 3D measurements.
Tomocube, founded from seed money funded by the EndRun Project of the Institute for Startup KAIST, succeeded in the commercialization of the 3D holographic microscopy and established an international distribution network in more than ten countries. It now has started exporting the product to several countries. The microscopes are being used in several leading research institutes including MIT, German Cancer Center, Pittsburg Medical Center, and Seoul National University Hospital Selected as one of the top ten mechanical technologies of 2016 by the Korean Society of Mechanical Engineers, the team raised four billion KRW investment from industry leaders including Soft Bank Venture Korea, Hanmi Pharmaceutical, and InterVest investment.
(Figure: Images of cells measured by 3D microscopy)
□ Designer Proteins with Chemical Modifications
By Hee-Sung Park and Hee Yoon Lee of the Department of Chemistry
Professor Hee-Sung Park developed a new strategy for installing authentic post-translational modifications (PTM) into recombinant proteins. Most essential biological processes are controlled by PTM, which plays a critical role in metabolic changes. However, abnormal protein modification aroused by environmental or genetic factors induce diverse diseases such as neurodegenerative diseases, cancer, and many other chronic diseases.
Professor Park has conceived a novel chemical biology route to achieve authentic and selective chemical modifications in proteins.He first used the established O-phosphoserine (Sep) orthogonal translational system to create a Sep-containing protein. The Sep residue is then dephosphorylated to dehydroalanine (Dha). Finally, Zn-Cu is conjugated to Dha of alkyl iodides, which enables it to form chemo-selective carbon-carbon bonds.
This approach offers a powerful tool to engineer designer proteins with diverse chemical modifications, providing a novel platform for investigating numerous diseases and drug development including for cancer and Alzheimer's. Furthermore, this research will allow mass production of abnormally modified proteins that could induce diseases, opening up new prospects in disease treatment research. It will help to enable investigation and discovery of new drug inhibitors that directly target abnormally modified proteins.
(Figure: Application of Customized Protein Modification Technology)
□ Lanthanum-Catalyzed Synthesis of Microporous 3D Graphene-Like Carbons in a Zeolite Template
By Ryong Ryoo, of the Department of Chemistry
Professor Ryong Ryoo’s team presented a scaled-up carbon synthesis viable for practical applications such as Li-ion batteries and catalyst supports.
Zeolite-templated carbon has an extremely large surface area and a regular microporous structure. As a result, it was expected to show excellent performance in various applications, such as for electrode materials or catalyst supports. However, until recently difficulties in synthesis have hindered research on application and properties of zeolited-templated carbon compared to other porous carbon materials.
Professor Ryoo’s team demonstrated that lanthanum ions embedded in zeolite pores lowered the temperature for carbonization of ethylene or acetylene. In this contribution, a graphene-like carbon structure was selectively formed inside zeolite template without the non-selective carbon deposition. Single crystal X-ray diffraction data revealed that carbon formed along the micropore surface. After removal of zeolite template, the carbon framework showed high electrical conductivity.
His synthesis method not only allowed selectivity in ethylene carbonization inside zeolite pore but permitted the diffusion of carbon material even when a large amount of zeolites was synthesized at once, allowing mass production of carbon. Thus, this method is expected to accelerate research on the application and properties of zeolite-templated carbon.
(Figure: Electron density distribution of zeolite that underwent selective pore carbonization. The structure of carbon determined by electron density distributions of carbon atoms, shown in yellow and red, within the framework of zeolite, shown in blue, can be observed.)
□ Complete Prevention of Blood Loss by Self-Sealing Hemostatic Needles
By Haeshin Lee of the Department of Chemistry
Professor Haeshin Lee’s team invented a hemostatic hypodermic needle, which prevented bleeding of punctured tissue during and after injections.
Bleeding unavoidably accompanies injections when a conventional needle penetrates tissue. Though the scale of bleeding from controlled injections does not cause harm to healthy individuals, uncontrolled bleeding may bring serious complications for those who suffer from hemophilia, coagulopathy, or who have been exposed to infectious diseases.
Professor Lee’s hemostatic hypodermic needle is coated with partially cross-linked catechol-functionalized chitosan that undergoes a solid-to-gel phase transition in situ to seal-seal punctured tissues. The team reported a complete prevention of blood loss following intravenous and intramuscular injections in animal models. They observed a 100% survival rate in hemophiliac mice following a syringe injection into a jugular vein.
The self-sealing hemostatic needles may help to prevent complications associated with bleeding in clinical settings such as for diabetic patients who experience delayed hemostasis and in the procedure of biopsy thereby preventing profuse bleeding.
□ An Immunological Mechanism for the Contribution of Commensal Microbiota Against Herpes Simplex Virus Infection in Genital Mucosa
By Heung Kyu Lee of the Graduate School of Medical Science and Engineering
Professor Heung Kyu Lee identified an immunological mechanism of commensal microbiota against herpes virus infections. The protective mechanisms of commensal bacteria against viral infections was limited to how immune inductive signals are provided by commensal bacteria for enhancing innate and adaptive immunity. Until Professor Lee’s research discovery, whether, or how, commensal bacteria might influence the effector arm of immune responses such as effector T cells to eliminate infected virus remained unknown.
Professor Lee’s team demonstrated that dysbiosis within the vaginal microbiota resulted in severe impairment of antiviral protection against HSV-2 infection. IL-33 released into the vaginal tract after antibiotic treatment blocked the ability of effector T cells to migrate into vaginal tissues and secrete the antiviral cytokine, IFN-γ. Thus, the findings suggested a previously unstudied role of commensal bacteria in the effector phase of the antiviral immune response against genital herpes. These findings provided insight into the mechanisms by which the secretion of proteases from opportunistic pathogens in susceptibility to various sexually transmitted pathogens might induce type 2 immunity within the female genital tract.
Promoting awareness of overuse of antibiotics, the research is expected to contribute to the development of viral vaccines with enhanced defense capacity by regulating commensal bacteria to promote health.
□ Development of a Pulse-Echo Laser Ultrasonic Propagation Imaging System
By Jung-Ryul Lee of the Department of Aerospace Engineering
Professor Jung-Ryul Lee’s team for the first time developed a mobile laser ultrasonic propagation imaging system that is capable of 2500-point inspection per second and visualization of pulse-echo ultrasonic wave through the thickness of a solid medium. This novel ultrasonic propagation visualization system has been successfully prototyped for the application of in-situ and in-process nondestructive evaluation of aerospace structures.
The real world proof-of-concept was achieved by testing the new system in the inspection of a space launcher fuselage (KSLV-II), control surfaces of military transport (CN-235), and the brake disk of F-16, guided weapon fuselage. In addition, the system has passed F-16 standard specimen test done by Korea Air Force and got a US patent. The prototype which was developed over a period of two years has been successfully delivered to Korea Air Force last December.
Furthermore, Boeing has expressed interest in prototype development project and KAIST OESL has been selected as the Boeing-KAIST technical contact lab and received a two-year grant from Boeing. The second prototype is under construction for Boeing and the third prototype will be delivered to an optional research institute and used as a standard inspection instrument.
□ Birefractive Stereo Imaging for Single-Shot Depth Acquisition
By Min H. Kim of the School of Computing
Professor Min H. Kim’s team proposed a novel 3D imaging method that allows the capture of not only color pictures but also corresponding depth images while traditional cameras capture just color pictures.
Depending on the polarization state of light, the incident light on a birefringent material such as calcite can be refracted into two different angles. This physical phenomenon is called double refraction. Whereas traditional stereo imaging requires at least two stereo cameras, 3D imaging method can capture depth from a single picture of double refraction. This proposed 3D imaging technique can be applied to many graphics and computer vision applications such as AR/VR applications that require color and depth information simultaneously.
This technology, which could measure depth images, is currently needed for various industrial applications. The suggested method in this research to measure depth information from one photo using double refraction media accurately can be used in areas where system size and cost are important, such as mobile cameras, VR/ARs, driverless cars, and 3D microscopes.
(Figure: Measuring high-resolution depth of single image via bi-refringent medium)
□Development of Environment Friendly Geotechnical Construction Material Using Biopolymer
By Gye-Chun Cho of the Department of Civil and Environmental Engineering
Professor Gye-Chun Cho has succeeded in making a 100% bio-based KABS (KAIST Bio-Soil) binder using biopolymer, an eco-friendly geotechnical construction material. A biopolymer is an organic polymer produced in the course of microbial activities and thus is an eco-friendly material manufactured without generating carbon dioxide. Biopolymers have been used in food, agriculture, cosmetics, and medicine as hardener and gelling agents, but have never been applied in construction. His team verified the microscopic interaction, feasibility, and strengthening mechanism of microbial biopolymers for soils for the first time in the world, suggesting that biopolymers be an eco-friendly soil binder.
In addition to soil binders, biopolymers can also be applied to various fields of ground construction (e.g., ground improvement, grouting, erosion control, vegetation, anti-desertification, etc.). The team expects more biopolymer applications in construction since increasing demands for replacing cement-based or chemical ground materials have surged.
With KABS binder, the team has performed several field tests along with industrial technology transfer underway. In collaboration with the Korea Expressway Corporation and LH Corporation, Professor Cho’s team is working on additional commercial applications.
(Figure: Strength enhancement effect of soil grain processed by biopolymer )
□ Protein Delivery Via Engineered Exosomes
By Chulhee Choi of the Department of Bio and Brain Engineering
Professor Chulhee Choi’s team unveiled a new tool for intracellular delivery of target proteins, named “exosomes for protein loading via optically reversible protein-protein interactions” or “EXPLORs”.
Nanoparticle-mediated delivery of functional macromolecules is a promising method for treating a variety of human diseases. Among nanoparticles, cell-derived exosomes have recently gained attention as a new therapeutic strategy for the in vivo delivery of nucleotides and chemical drugs.
By integrating a reversible protein-protein interaction module controlled by blue light with the endogenous process of exosome biogenesis, the team successfully loaded cargo proteins into newly generated exosomes. Treatment with protein-loaded EXPLORs is shown to significantly increase intracellular levels of cargo proteins and their function in recipient cells in vitro and in vivo.
These results clearly indicate the potential of EXPLORs as a mechanism for the efficient intracellular transfer of protein-based therapeutics into recipient cells and tissues. This technology has been transferred to KAIST bio-venture Cellex Life Science, Incorporated for commercialization.
□ Hot Electron Detection under Catalytic Reactions
By Jeong Young Park of the Graduate School of EEWS
Professor Jeong Young Park’s team developed a novel catalytic nanodiode consisting of a thin metal catalyst deposited onto a semiconductor support. The team succeeded in observing in real-time hot electrons created in the course of catalytic reaction occurring at atmospheric pressure or at liquid-solid interfaces.
Use of a noble catalytic nanodiode is a new measurement system that detects hot electrons produced on catalyst surface through atmospheric pressure and liquid chemical reaction in real time that allows direct identification of the catalytic activity of catalytic reactions. In particular, the system allows macro-observation of hot-electron movements that change with the type of nano-catalyst without high-priced equipment in atmospheric pressure and liquidation, and thus is not limited to experimental conditions such as in ultrahigh vacuums.
Therefore, it could be applied in the future to analyze complex chemical reaction mechanisms of catalysts used in high temperature and various pressure conditions, and to develop high efficiency next-generation catalyst materials. This finding may lead not only to the fundamental understanding in the mechanism of the catalytic reactions but also to the development of next-generation catalysts with enhanced catalytic performance.
(Figure: Schematic diagrams of nano-catalyst hot electron element and graphene hot electron detector)
2017.02.20 View 13080 -
Professor Hahn Named Sangnam Business Researcher Awardee
Professor Minhi Hahn of the School of Management Engineering at the KAIST College of Business has been named the winner of the 22nd Sangnam Business Researcher Award. The Sangnam Award is the highest distinction made by the Korean Academic Society of Business Administration to recognize an outstanding scholar in the field of business & management for that year.
His research focuses on how marketing communication impacts customer choices and their satisfaction. Professor Hahn has served on the faculty of the College of Business since 1989, and has supervised more than 21 Ph.D.s and 203 master’s students while publishing more than 51 papers in domestic and foreign journals. He served as dean of the KAIST College of Business, president of the Korean Marketing Association, and president of the Korean Society of Consumer Studies. Currently Professor Hahn is a board member on the strategic committee of the College of Management at National Sun Yat-sen University in Taiwan.
Professor Hahn said, “I am pleased to receive this award on behalf of the people who are working for the development of Korean business administration. I will do my utmost to support younger scholars to continue their meaningful research." The award ceremony will take place at the Plaza Hotel in Seoul on February 23.
2017.02.19 View 6155 -
Professor Shin Honored Posthumously for Iridescent Microparticles
(The Late Professor Joong-Hoon Shin (left) and Professor Shin-Hyun Kim)
A research team co-led by Professor Shin-Hyun Kim from the Department of Chemical and Biomolecular Engineering and Professor Jong-Ryul Jeong from the Department of Materials Science and Engineering at Chungnam National University developed iridescent microparticles with a structural color gradient. The research team posthumously dedicated their research to a renowned professor in the field of nanophotonics, the late Professor Joong-Hoon Shin of the Graduate School of Nanoscience and Technology at KAIST. He passed away suddenly in a car accident last September.
The iridescent microparticles, which allow on-demand control over structural color, will be key components for next-generation reflection-mode displays with clear color realization even in direct sunlight.
Materials such as opals, Morpho butterfly wings, and peacock feathers all display beautiful colors without pigment, using regularly-spaced nanostructures. Regularly-spaced nanostructures render color, by selectively reflecting the light of a particular wave through light interference. As such, materials that possess periodic modulation of refractive index at subwavelength scale are referred to as photonic crystals.
In general, photonic crystals are only able to display a single color, so limitations exist when attempting to apply them to reflection-mode displays which call for multiple structural colors. The research team addressed the issue using inspiration from snowflakes stacking in the winter. When snow falls on the surface of a round-shaped structure, the thickness of the snow stacking differs depending on the orientation. Based on this observation, the research team created photonic microparticles with a structural color gradient by depositing two different materials on spherical microparticles.
When some material is deposited on the surface of a sphere, the material on the top is thickest and becomes thinner on the sides. The team alternately deposited titania and silica on the spherical microparticles to form periodic modulation of the refractive index. The thickness of the alternating photonic layers is reduced along the angle from the top, which yields a structural color gradient.
Consequently, the microparticles reflect long-wavelength red light from the top of the sphere and short-wavelength blue light from the side of the sphere. Any color of the visible spectrum can be selected in between the top and side depending on the orientation of the microparticles.
The research team used an external magnetic field as a way to control the orientation of the photonic microparticles and the structural colors. As magnetic iron layer was deposited underneath the alternating photonic layer, it was possible to freely control the orientation of the microparticles using a magnet, thereby allowing control of the color seen by the users.
KAIST doctoral candidate Seung Yeol Lee of the Department of Chemical and Biomolecular Engineering is the first author of this research, with support from the Midcareer Researcher Program of the National Research Foundation and funded by the Ministry of Science, ICT, and Future Planning (MSIP). This research was published in the online edition of Advanced Materials on February 6, 2017.
Figure1: Sets of an OM image of photonic Janus microspheres and an SEM image showing a cross-section of the photonic layers.
Figure 2: A series of schematics and OM images showing the color change depending on the orientation angle of the photonic Janus microsphere.
2017.02.17 View 7986 -
KAIST Celebrates the 2017 Commencement
KAIST hosted its 2017 Commencement, awarding diplomas to 2,767 members of the Class of 2017 during a ceremony on February 17. President Sung-Mo Kang, Minister Yang-hee Choi of Science, ICT, and Future Planning, and Chairman of the KAIST Board of Trustees Jang-Moo Lee joined the ceremony along with the graduates and their family and friends at the Ryu Keun Chul Sports Complex.
The graduating class included 638 Ph.D. degrees, 1,335 Master’s degrees, and 794 Bachelor’s degrees being conferred. Among them, Young-Ki Song from the Department of Electric Engineering was honored to win the Minister’s Award, the highest award bestowed to an undergraduate. The KAIST Presidential Award went to Min-Jae Park of the Department of Mathematical Sciences and the KAIST Board of Trustee Chairman’s Award was presented to Jae-Hyung Cho from the Department of Mechanical Engineering.
Including this year’s graduating class, KAIST has turned out more than 59,000 highly educated science and technology talents including 11,731 Ph.D.s since its foundation in 1971. This year, 24-year-old Seo-Hee Oh earned her Ph.D. in chemistry as the youngest Ph.D. of the year after completing her Master’s and Ph.D. combined course in three years.
President Sung-Mo Kang praised the creativity of this graduating class and their excellent ability in his charge, saying, “As future leaders of our society, you are expected to develop a sense of compassion and outstanding professionalism to contribute to the advancement of not only Korea but also the whole world.’
For full text of President Kang’s charge to the graduates, please click.
2017.02.17 View 7617 -
An Improved Carbon Nanotube Semiconductor
Professor Yang-Kyu Choi and his research team of the School of Electrical Engineering at KAIST collaborated with Professor Sung-Jin Choi of Kookmin University to develop a large-scale carbon nanotube semiconductor by using a 3-D fin-gate structure with carbon nanotubes on its top.
Dong Il Lee, a postdoctoral researcher at KAIST’s Electrical Engineering School, participated in this study as the first author. It was published in ACS Nano on November 10, 2016, and was entitled “Three-Dimensional Fin-Structured Semiconducting Carbon Nanotube Network Transistor.”
A semiconductor made with carbon nanotubes operates faster than a silicon semiconductor and requires less energy, yielding higher performance.
Most electronic equipment and devices, however, use silicon semiconductors because it is difficult to fabricate highly purified and densely packed semiconductors with carbon nanotubes (CNTs).
To date, the performance of CNTs was limited due to their low density. Their purity was also low, so it was impossible to make products that had a constant yield on a large-surface wafer or substrate. These characteristics made the mass production of semiconducting CNTs difficult.
To solve these difficulties, the research team used a 3-D fin-gate to vapor-deposit carbon nanotubes on its top. They developed a semiconductor that had a high current density with a width less than 50 nm.
The three-dimensional fin structure was able to vapor-deposit 600 carbon nanotubes per micrometer. This structure could have 20 times more nanotubes than the two dimensional structure, which could only vapor-deposit thirty in the same 1 micrometer width.
In addition, the research team used semi-conductive carbon nanotubes having a purity rating higher than 99.9% from a previous study to obtain a high yield semiconductor.
The semiconductor from the research group has a high current density even with a width less than 50 μm. The new semiconductor is expected to be five times faster than a silicon-based semiconductor and will require five times less electricity during operation.
Furthermore, the new semiconductor can be made by or will be compatible with the equipment for producing silicon-based semiconductors, so there will be no additional costs.
Researcher Lee said, “As a next generation semiconductor, the carbon nanotube semiconductor will have better performance, and its effectiveness will be higher.” He also added, “Hopefully, the new semiconductor will replace the silicon-based semiconductors in ten years.”
This study received support from the Center for Integrated Smart Sensors funded by the Ministry of Science, ICT & Future Planning of Korea as the Global Frontier Project, and from the CMOS (Complementary Metal-Oxide-Semiconductor) THz Technology Convergence Center of the Pioneer Research Center Program sponsored by the National Research Foundation of Korea.
Picture 1: 3D Diagram of the Carbon Nanotube Electronic Device and Its Scanning Electron Microscope (SEM) Image
Picture 2: 3D Transistor Device on an 8-inch Base and the SEM Image of Its Cross Section
2017.02.16 View 9542 -
New Building Endowed in Bio and Brain Engineering Department
An endowment from the former Chairman of Mirae Industries, Moon Soul Chung, was used to establish the Yang Bun Soon Building in the Bio and Brain Engineering Department at KAIST. The opening ceremony for the building took place on February 8 and was attended by President Sung-Mo Kang, KAIST administrators, faculty, and students.
The Yang Bun Soon Building, named after the wife of Chairman Chung, is a new addition to the Bio and Brain Engineering Department complex. The five-story building was erected next to the 11-story Chung Moon Soul Building, which was completed in 2003 using a portion of his first endowment to KAIST. Chairman Chung donated approximately 30 billion KRW for funding a convergence research for IT and BT in 2001.
The new building was completed with financing from Chung’s second endowment of 21.5 billion KRW in support of the fields of brain and cognitive sciences in 2014. The building will accommodate both lab facilities and lecture halls.
At the ceremony, President Kang thanked the Chungs for their continuing generosity to KAIST. He commended Chung for showing how entrepreneurs can fulfill their social responsibility by supporting Korea’s future through donations and support.
(Photo caption: Chung Moon Soul Building (left) and Yang Bun Soon Building(right))
2017.02.09 View 5190 -
Dr.M Drives Smart Healthcare Industry in Partnership with Hancom
President Sung-Mo Kang signed an agreement on January 25 with Hancom Group Chairman Sang Chul Kim to establish a smart healthcare complex in Gapyeong, Kyonggido. With the Gapyeong complex launch, KAIST will come to commercialize Dr. M system along with other Dr.M consortium members as a new growth engine to drive the smart health industry.
Dr. M is a smart healthcare platform developed by the Health Science Research Institute at KAIST in 2014. Dr. M is capable of analyzing and predicting diseases, as well as prescribing, by incorporating ICT and medical technologies. Dr. M applies diverse technologies such as healthcare sensors, wearable devices, low-power communications technology, and cloud and big data collection platforms.
Hancom Group, a leading computer software company in Korea, has participated in the project since 2015 for advancing the smart healthcare market by developing mobile healthcare software program. Hancom joined the Dr.M consortium launched last November.
(President Kang (left) poses with Hancom Chairman Kim after signing.)
2017.02.03 View 5542 -
A New Approach to 3D Holographic Displays Greatly Improves the Image Quality
With the addition of holographic diffusers or frosted glasses to wavefront modulators, KAIST researchers offer a simple and practical solution to significantly enhance the performance of 3D dynamic holographic displays by 2,600 times.
The potential applications of three-dimensional (3D) digital holograms are enormous. In addition to arts and entertainment, various fields including biomedical imaging, scientific visualization, engineering design, and displays could benefit from this technology. For example, creating full-sized organs for 3D analysis by doctors could be helpful, but it remained a challenge owing to the limitation of hologram-generation techniques.
A research team led by Professor YongKeun Park of the Physics Department at KAIST has come up with a solution and developed a 3D holographic display that performs more than 2,600 times better than existing 3D holographic displays. This study is expected to improve the limited size and viewing angle of 3D images, which were a major problem of the current holographic displays. The study was published online in Nature Photonics on January 23, 2017.
3D holograms, which often appear in science fiction films, are a familiar technology to the public, but holograms in movies are created with computer graphic effects. Methods for creating true 3D holograms are still being studied in the laboratory. For example, due to the difficulty of generating real 3D images, recent virtual reality (VR) and augmented reality (AR) devices project two different two-dimensional (2D) images onto a viewer to induce optical illusions.
To create a 3D hologram that can be viewed without special equipment such as 3D glasses, the wavefront of light must be controlled using wavefront modulators such as spatial light modulators (SLMs) and deformable mirrors (DMs). A wavefront modulator is an optical manipulation device that can control the direction of light propagation.
However, the biggest limitation to using these modulators as 3D displays is the number of pixels. The large number of pixels that are packed into high-resolution displays developed in recent years are suitable for a 2D image, and the amount of information contained in those pixels cannot produce a 3D image. For this reason, a 3D image that can be made with existing wavefront modulator technology is 1 cm in size with a narrow viewing angle of 3 degrees, which is far from practicable.
As an alternative, KAIST researchers used a DM and added two successive holographic diffusers to scatter light. By scattering light in many directions, this allows for a wider viewing angle and larger image, but results in volume speckle fields, which are caused by the interference of multiple scattered light. Random volume speckle fields cannot be used to display 3D images.
To fix the problem, the researchers employed a wavefront-shaping technique to control the fields. As a result, they succeeded in producing an enhanced 3D holographic image with a viewing angle of 35 degrees in a volume of 2 cm in length, width, and height. This yielded a performance that was about 2,600 times stronger than the original image definition generated when they used a DM without a diffuser.
Professor Park said, “Scattering light has previously been believed to interfere with the recognition of objects, but we have demonstrated that current 3D displays can be improved significantly with an increased viewing angle and image size by properly controlling the scattered light.”
Hyeonseung Yu, who is the lead author of this research article and a doctoral candidate in the Department of Physics, KAIST, noted that this technology signals a good start to develop a practical model for dynamic 3D hologram displays that can be enjoyed without the need for special eyeglasses. “This approach can also be applied to AR and VR technology to enhance the image resolution and viewing angles,” added Yu.
The research paper is entitled “Ultrahigh-definition Dynamic 3D Holographic Display by Active Control of Volume Speckle Fields.”
Figure 1. Concept of Scattering Display
The size and viewing angle of 3D images can be simultaneously increased when a scattering medium (diffuser) is introduced. By controlling the wavefront impinging on the scattering medium, the desired 3D hologram is generated.
Figure 2. Experimental Setup
The optical set-up consists of a deformable mirror and the scattering medium with two successive holographic diffusers. A high-numerical-aperture imaging unit mounted on a three-axis motorized translational system is utilized for wavefront optimization and imaging.
Figure 3. 3D Images Projected
This picture shows 3D images in a volume of 2 cm × 2 cm × 2 cm with a viewing angle of 35 degrees using one of the wavefront modulators, a digital micromirror device (DMD).
Figure 4. Artist’s Rendition of the Proposed Concept
A dynamic 3D hologram of a face is displayed.
2017.02.01 View 12632 -
KAIST Intensive Science Camp for Middle-High School Students
The KAIST Global Institute of Talented Education (Director: Dong-Soo Kwon) invited around 90 middle and high school students for an advanced science intensive camp from January 22 to 24.
This camp targeted middle and high school students in community centers or child-care institutions. It aims to increase students’ interest in science and engineering, and assist them with their career paths through programs such as special lectures on science, advanced science projects, and career mentoring.
Participating students were divided into groups of seven or eight with a KAIST student as a mentor to conduct advanced science projects such as VR controller production and robot arm programming. The camp included exploring future career options and science and engineering college admission counselling.
Jiyoung Ryu, Research Professor for the KAIST Global Institute of Talented Education, said, “KAIST started the science and engineering career experience program in 2016 with the Ministry of Education and Korea Research Institute for Vocational Education and Training (KRIVET). So far, 6000 middle and high school students from around the country have participated. The camp is more meaningful since it educates students in social responsibility, in addition to the fields of science and engineering, both of which are missions and goals that KAIST strives for.” She continued to say, “We plan to continue to expand the program in the future.”
The KAIST Global Institute of Talented Education is actively conducting research and projects on national education for talented youth such as policy research concerning gifted education, science and engineering career education, advanced science camps, training for gifted education teachers, and cyber gifted education programs.
2017.02.01 View 6937 -
EWB-KAIST Wraps up Five-Year Project in Nepal
‘Engineers Without Borders-KAIST (EWB-KAIST)’ led by Professor Tae-ho Song from the Department of Mechanical Engineering returned to Korea on January 10 after a two-week project in Nangi, Nepal.
EWB-KAIST was established in 2012 by KAIST students and professors. Since then, the team visited Nangi, in the Annapurna region of Nepal, to engage in Appropriate Technology (AT) development projects. The projects included building passive houses and small hydroelectric power, and teaching science education. In particular, passive houses that use straw as an insulator received great a reception from the locals.
This was their last visit to Nepal, since the five-year project has now come to an end. Future projects in Mongolia will be led by Professor Buhm Soon Park from the Graduate School of Science and Technology Policy.
Professor Song commented, “I am glad that the Nepal project was successfully conducted over the last five years. To make sure the support does not end here, I will personally continue to visit the Himalayas to assist the villagers.”
EWB-KAIST is a non-profit organization that conducts activities with the aim of AT development and providing support for less-developed countries in need of the benefits of technology.
( Passive house made of straws by EWB-KAIST team in Nangi, Nepal.)
2017.02.01 View 6196