Kaist

KAIST Develops Core Technology for Ultra-small 3D ..

(from left: Dr. Jong-Bum Yo, PhD candidate Seong-Hwan Kimand Professor Hyo-Hoon Park) A KAIST research team developed a silicon optical phased array (OPA) chip, which can be a core component for three-dimensional image sensors. This research was co-led by PhD candidate Seong-Hwan Kim and Dr. Jong-Bum You from the National Nanofab Center (NNFC). A 3D image sensor adds distance information to a two-dimensional image, such as a photo, to recognize it as a 3D image. It plays a vital role in various electronics including autonomous vehicles, drones, robots, and facial recognition systems, which require accurate measurement of the distance from objects. Many automobile and drone companies are focusing on developing 3D image sensor systems, based on mechanical light detection and ranging (LiDAR) systems. However, it can only get as small as the size of a fist and has a high possibility of malfunctioning because it employs a mechanical method for laser beam-steering. OPAs have gained a great attention as a key component to implement solid-state LiDAR because it can control the light direction electronically without moving parts. Silicon-based OPAs are small, durable, and can be mass-produced through conventional Si-CMOS processes. However, in the development of OPAs, a big issue has been raised about how to achieve wide beam-steering in transversal and longitudinal directions. In the transversal direction, a wide beam-steering has been implemented, relatively easily, through a thermo-optic or electro-optic control of the phase shifters integrated with a 1D array. But the longitudinal beam-steering has been remaining as a technical challenge since only a narrow steering was possible with the same 1D array by changing the wavelengths of light, which is hard to implement in semiconductor processes. If a light wavelength is changed, characteristics of element devices consisting the OPA can vary, which makes it difficult to control the light direction with reliability as well as to integrate a wavelength-tunable laser on a silicon-based chip. Therefore, it is essential to devise a new structure that can easily adjust the radiated light in both transversal and longitudinal directions. By integrating tunable radiator, instead of tunable laser in a conventional OPA, Professor Hyo-Hoon Park from the School of Electrical Engineering and his team developed an ultra-small, low-power OPA chip that facilitates a wide 2D beam-steering with a monochromatic light source. This OPA structure allows the minimizing of the 3D image sensors, as small as a dragonfly’s eye. According to the team, the OPA can function as a 3D image sensor and also as a wireless transmitter sending the image data to a desired direction, enabling high-quality image data to be freely communicated between electronic devices. Kim said, “It’s not an easy task to integrate a tunable light source in the OPA structures of previous works. We hope our research proposing a tunable radiator makes a big step towards commercializing OPAs.” Dr. You added, “We will be able to support application researches of 3D image sensors, especially for facial recognition with smartphones and augmented reality services. We will try to prepare a processing platform in NNFC that provides core technologies of the 3D image sensor fabrication.” This research was published in Optics Letters on January 15. Figure 1.The manufactured OPA chip Figure 2. Schematic feature showing an application of the OPA to a 3D image sensor

KAIST Presents Innovations at CES 2019

Ten of the most innovative technologies spun off from KAIST made a debut at the Consumer Electronics Show (CES) 2019, the world’s largest consumer electronics and IT exhibition being held in Las Vegas from January 8 to 11. The KAIST booth at the CES featured technologies made by KAIST research teams and five startup companies including LiBEST, Memslux, and Green Power. In particular, the KAIST Alumni Association invited 33 aspiring alumni entrepreneurs selected from the KAIST Startup Competition to the show. At the exhibition, KAIST is presenting innovations in the fields of AI and Bio-IT convergence for the Fourth Industrial Revolution. These include real-time upscaling from Full HD to 4K UHD using AI deep learning-based convolutional neural networks (Professor Munchurl Kim, School of Electrical Engineering) and an AI conversation agent that responds to user’s emotions (Professor Soo-Young Lee, School of Electrical Engineering). Other technologies include optimal drug target identification by cancer cell type through drug response prediction to be used in personalized cancer treatments (Professor Kwang-Hyun Cho, Department of Bio and Brain Engineering), a nanofiber-based color changing gas sensor with greater sensitivity than conventional paper-based color changing sensors (Professor Il-Doo Kim, Department of Materials Science and Engineering), and functional near-infrared spectroscopy (fNIRS) for brain imaging and muscle fatigue measurement (Professor Hyeonmin Bae, School of Electrical Engineering).  The KAIST booth also features startups founded by KAIST alumni including LiBEST with a flexible lithium polymer secondary cell optimized for smart wearable devices and Rempus with a high-performance lithium ion cell packaging technology for outstanding safety, high capacity, long life, and fast charging. Green Power and Smart Radar Systems are also joining the booth with a highly efficient and eco-friendly wireless charging system for electrical cars, and a 4D image radar sensor that detects 3D images and speed in real time for applications in self-driving cars, drones, and security systems respectively. Faculty-founded startup Memslux (CEO Jun-Bo Yoon, School of Electrical Engineering) is presenting a transparent surface light source solution for next-generation display devices. Associate Vice President of Office of University-Industry Cooperation Kyung Cheol Choi said, “I believe that universities should play a role in connecting technological innovations to business startups for creating value at a global level. In that sense, it is a great opportunity to present innovative technologies from KAIST and promote outstanding KAIST startups at CES 2019. Hopefully, this experience will lead to joint R&D, investment, cooperation, and international technology transfer contracts with leading companies from around the world.” Here are the five key technologies presented by KAIST at CES 2019.

A Comprehensive Metabolic Map for Production of Bi..

A KAIST research team completed a metabolic map that charts all available strategies and pathways of chemical reactions that lead to the production of various industrial bio-based chemicals. The team was led by Distinguished Professor Sang Yup Lee, who has produced high-quality metabolic engineering and systems engineering research for decades, and made the hallmark chemicals map after seven years of studies. The team presented a very detailed analysis on metabolic engineering for the production of a wide range of industrial chemicals, fuels, and materials. Surveying the current trends in the bio-based production of chemicals in industrial biotechnology, the team thoroughly examined the current status of industrial chemicals produced using biological and/or chemical reactions. This comprehensive map is expected to serve as a blueprint for the visual and intuitive inspection of biological and/or chemical reactions for the production of interest from renewable resources. The team also compiled an accompanying poster to visually present the synthetic pathways of chemicals in the context of their microbial metabolism. As metabolic engineering has become increasing powerful in addressing limited fossil resources, climate change, and other environmental issues, the number of microbially produced chemicals using biomass as a carbon source has increased substantially. The sustainable production of industrial chemicals and materials has been explored with micro-organisms as cell factories and renewable nonfood biomass as raw materials for alternative petroleum. The engineering of these micro-organism has increasingly become more efficient and effective with the help of metabolic engineering – a practice of engineering using the metabolism of living organisms to produce a desired metabolite. With the establishment of systems metabolic engineering – the integration of metabolic engineering with tools and strategies from systems biology, synthetic biology and evolutionary engineering – the speed at which micro-organisms are being engineered has reached an unparalleled pace. In order to evaluate the current state at which metabolically engineered micro-organisms can produce a large portfolio of industrial chemicals, the team conducted an extensive review of the literature and mapped them out on a poster. This resulting poster, termed the bio-based chemicals map, presents synthetic pathways for industrial chemicals, which consist of biological and/or chemical reactions. Industrial chemicals and their production routes are presented in the context of central carbon metabolic pathways as these key metabolites serve as precursors for the chemicals to be produced. The resulting biochemical map allows the detection and analysis of optimal synthetic pathways for a given industrial chemical. In addition to the poster, the authors have compiled a list of chemicals that have successfully been produced using micro-organisms and a list of the corresponding companies producing them commercially. This thorough review of the literature and the accompanying analytical summary will be an important resource for researchers interested in the production of chemicals from renewable biomass sources. Metabolically engineered micro-organisms have already made a huge contribution toward the sustainable production of chemicals using renewable resources. Professor Lee said he wanted a detailed survey of the current state and capacity of bio-based chemicals production. “We are so excited that this review and poster will expand further discussion on the production of important chemicals through engineered micro-organisms and also combined biological and chemical means in a more sustainable manner,” he explained. This work was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biofineries from the Ministry of Science and ICT through the National Research Foundation of Korea. For further information, Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering at KAIST ( leesy＠kaist.ac.kr , Tel: ＋82-42-350-3930) Figure: Bio-based chemicals production through biological and chemical routes. This metabolic map describes representative chemicals that can be produced either by biological and/or chemical means. Red arrows represent chemical routes and blue arrows represent biological routes. Intermediate metabolites in the metabolism of a living organism can serve as a platform toward the production of industrially relevant chemicals. A more comprehensive map presented by the team can be found as a poster in the review.

[AI＋X Forum] AI ＋ Politics

The KAIST School of Computing is excited to announce AI＋X Forum, a series of talks and discussions designed to ask how AI can impact various aspects of our society, including but not limited to politics, policy, education, law, labor, life, and art. Our first event will be on AI＋Politics with two distinguished speakers. Please refer to the poster below for details. Refreshments will be provided from 9:30. The talks and discussion will be in English. Date & Time: 10:00-12:00, Jan. 17, 2019 (Thu) Location: N1-201 Speakers: - Co-designing Policy and Technology for AI (Prof. So Young Kim, KAIST) - Mapping Political Communities: A Statistical Analysis of Lobbying Networks in Legislative Politics (Prof. In Song Kim, MIT) Best, AI＋X Forum Organizers (Sung-Hyon Myaeng, Alice Oh, Meeyoung Cha, Juho Kim) https://irnlpkaist.wixsite.com/aix-kaist

Distinguished Alumni Awardees 2018

The KAIST Alumni Association (KAA) announced four recipients of the Distinguished Alumni Awards 2018. The Distinguished Alumni Awards recognize graduates who have achieved outstanding accomplishments in their professional and personal lives, and who have been an inspiration to fellow alumni and students in Korea and around the globe. Since the establishment of the award in 1992, a total of 99 alumni at home and abroad have been honored as recipients. The awards ceremony will take place during the New Year Alumni Reception on January 19 in Seoul. Yeungnam University President Gil-Soo Sur (’75 MS, ’78 PhD in Chemistry) has demonstrated leadership in higher education and gained trust in academia for playing a leading role in educational innovation as well as serving as an educator who has fostered outstanding research talents for decades. Professor Kwang-Soo Kim (’77 MS, ’79 PhD in Life Science) is the director of the Molecular Neurobiology Laboratory at McLean Hospital at Harvard Medical School. He has more than 20 years of experience investigating molecular and developmental neurobiology of the midbrain dopamine neuronal system. He has contributed to developing cell replacement therapy for Parkinson’s disease and has pioneered a generation of safe human-induced pluripotent stem cells through the direct delivery of reprogrammed proteins. Young-Hwan Moon (’82 MS, ’87 PhD in Chemistry and Biomolecular Engineering) is the CEO of Coretech, which specializes in producing specialty gases and environmental catalysts required for chemical processes. He was recognized for enhancing national competence by securing competitive technology for manufacturing products. Young-Hyun Jun (’84 MS, ’86 PhD in Electrical Engineering), the CEO of Samsung SDI, is a globally renowned expert in memory semiconductors. By bringing about innovative technology to enhance productivity and processes, he led Samsung Electronics to become the number one company at the global level in the field of semiconductors.

KAIST Class of ’78 Celebrates 40-Year Reunion

(from left: Chairman Hyung Kyu Lim from the KAIST Alumni Scholarship Foundation and KAIST President Sung-Chul Shin) The Class of 1978 reunited on May 26 at the College of Business on the KAIST Seoul Campus, which was the main campus when they were students 40 years ago. Now leaders of Korea in the sectors of industry, academia, and research, the Class of ’78 held a homecoming event in celebration of the 40th anniversary of their graduation. Approximately 120 guests attended the event, including the head of the KAIST Alumni Association Ki-Chul Cha, Emeritus Professor Jae-Kyoon Kim, and Emeritus Professor Choong-Ki Kim from the School of Electrical Engineering. The Class of ’78 includes Man Gi Paik from the Ministry of Trade, Industry and Energy, Chairman Hyung Kyu Lim from the KAIST Alumni Scholarship Foundation, President Sang Hyuk Son from Daegu Gyeongbuk Institute of Science & Technology, and Provost and Executive Vice President O Ok Park from KAIST. At the event, the Class of ‘78 donated a scholarship worth 1.5 billion KRW. Chairman Lim said, “We will put every effort into helping KAIST students who will be future leaders. We hope this fund will go toward students who will create new value and contribute to society.” President Shin added, “The effort and affection of the alumni will be a strong foundation for KAIST taking the next big step. In response to the support and affection of 61,125 KAIST alumni, KAIST will make every effort to become a world-leading university.”

Do Not Erect a Wall, Build a Bridge

(Mr. Ban gave a lecture on UN and Global Citizenship at KAIST)  “People are saying that multilateralism is under threat, but I believe that it has helped others keep away from wars. There are currently invisible walls among countries. But do not erect the wall, build the bridge！” On December 7, KAIST invited one of the most admired people by Korea’s younger generation to give a lecture on UN and Global Citizenship, as the final session of the Global Leaders Lecture Series 2018. He is the 33th Minister of Foreign Affairs and the 8th Secretary-General of the United Nations, Ban Ki-Moon. Mr. Ban is recognized for making significant contributions to world peace and environmental preservation during his term at the UN. Mr. Ban first opened his lecture by explaining his great expectations for KAIST students. “KAIST is one of the outstanding universities that fosters the world’s best scientists and for that I have a great expectations for your role in the era of the Fourth Industrial Revolution. In this rapidly changing society, acquiring global citizenship is most important,” he said. Who are global citizens? According to UNESCO, they are ‘active promoters of more peaceful, tolerant, inclusive, secure and sustainable societies’. He stated that global leaders lacking global citizenship has resulted in so many disputes among countries and concerns for themselves. This concept of global citizenship came to him when he studied abroad in the U.S as a young man and met John F. Kennedy. He said, “It touched my heart although I was young. He (John F. Kennedy) told me that the world leaders were not getting along well. During the hype of the Cold War, national boundaries were meaningless. The question was whether I could help others. He then encouraged me, telling me that I could change it because I was young.” Mr. Ban proposed four required mindsets for global citizenship. The first is to have respect, empathy, and trustworthiness for others. He believes that speaking is the foundation of knowledge, while listening is the foundation of wisdom. Although the concept of philosophy might vary between the East and West, listening to others is very important for gaining respect, empathy, and trustworthiness. The second is to be future-oriented, particularly for scientists who have the potential to change civilization. He encouraged the audience to look to the future by sharing his story about climate change. “During my term, I received strong advice from scientists that led me to prioritize the issue of climate change. I focused on climate change for better living conditions around the world.” He also added, “This cannot be done by one country. We need to all work together to live harmoniously with nature.” Third, having a critical mindset is important, especially for scientists because it helps with solving problems by taking a scientific approach, without missing any of the small things. It is essential for scientists to find out new things, particularly in the era of the Fourth Industrial Revolution and informatization; however, they need to keep in mind how their findings will affect us. For instance, they need to question how robotics will change humans’ living patterns, as well as their role and how it links to humanity. Last but not least, passion, which goes along with compassion, is required for helping others. Ban thinks people without passion are like the walking dead. When pursuing policies, they need to have the passion to drive it. At the same time, they need to have compassion for creating a happier life for everyone. Mr. Ban ended by saying to the students, “You did not lead the era of informatization, but you are the beneficiaries of it. Acquiring global citizenship, you need to think how you can help even out the growth across the globe through the development of science during this era.”

Fabrication of Shape-conformable Batteries Based o..

(from left: Dr. Bok Yeop Ahn, Dr. Chanhoon Kim, Professor Il-Doo Kim and Professor Jennifer A. Lewis) Flexible, wireless electronic devices are rapidly emerging and have reached the level of commercialization; nevertheless, most of battery shapes are limited to either spherical and/or rectangular structures, which results in inefficient space use. Professor Il-Doo Kim’s team from the Department of Materials Science at KAIST has successfully developed technology to significantly enhance the variability of battery design through collaboration research with Professor Jennifer A. Lewis and her team from the School of Engineering and Applied Sciences at Harvard University. Most of the battery shapes today are optimized for coin cell and/or pouch cells. Since the battery as an energy storage device occupies most of the space in microelectronic devices with different designs, new technology to freely change the shape of the battery is required. The KAIST-Harvard research collaboration team has successfully manufactured various kinds of battery shapes, such as ring-type, H, and U shape, using 3D printing technology. And through the research collaboration with Dr. Youngmin Choi at the Korea Research Institute of Chemical Technology (KRICT), 3D-printed batteries were applied to small-scale wearable electronic devices (wearable light sensor rings). The research group has adopted environmentally friendly aqueous Zn-ion batteries to make customized battery packs. This system, which uses Zn2＋ instead of Li＋ as charge carriers, is much safer compared with the conventional lithium rechargeable batteries that use highly inflammable organic electrolytes. Moreover, the processing conditions of lithium-ion batteries are very complicated because organic solvents can ignite upon exposure to moisture and oxygen. As the aqueous Zn-ion batteries adopted by the research team are stable upon contact with atmospheric moisture and oxygen, they can be fabricated in the ambient air condition, and have advantages in packaging since packaged plastic does not dissolve in water even when plastic packaging is applied using a 3D printer. To fabricate a stable cathode that can be modulated in various forms and allows high charge-discharge, the research team fabricated a carbon fiber current collector using electrospinning process and uniformly coated electrochemically active polyaniline conductive polymer on the surface of carbon fiber for a current collector-active layer integrated cathode. The cathode, based on conductive polyaniline consisting of a 3D structure, exhibits very fast charging speeds (50％ of the charge in two minutes) and can be fabricated without the detachment of active cathode materials, so various battery forms with high mechanical stability can be manufactured. Prof. Kim said, “Zn-ion batteries employing aqueous electrolytes have the advantage of fabrication under ambient conditions, so it is easy to fabricate the customized battery packs using 3D printing.” “3D-printed batteries can be easily applied for niche applications such as wearable, personalized, miniaturized micro-robots, and implantable medical devices or microelectronic storage devices with unique designs,” added Professor Lewis. With Dr. Chanhoon Kim in the Department of Materials Science and Engineering at KAIST and Dr. Bok Yeop Ahn School of Engineering and Applied Sciences at Harvard University participating as equally contributing first authors, this work was published in the December issue of ACS Nano. This work was financially supported by the Global Research Laboratory (NRF-2015K1A1A2029679) and Wearable Platform Materials Technology Center (2016R1A5A1009926). Figure 1.Fabrication of shape-conformable batteries based on 3D-printing technology and the application of polyaniline carbon nanofiber cathodes and wearable electronic devices Figure 2.Fabricated shape-conformable batteries based on a 3D-printing method Meanwhile, Professor Il-Doo Kim was recently appointed as an Associate Editor of ACS Nano, a highly renowned journal in the field of nanoscience. Professor Kim said, “It is my great honor to be an Associate Editor of the highly renowned journal ACS Nano, which has an impact factor reaching 13.709 with 134,596 citations as of 2017. Through the editorial activities in the fields of energy, I will dedicate myself to improving the prominence of KAIST and expanding the scope of Korea’s science and technology. I will also contribute to carrying out more international collaborations with world-leading research groups.” (Associate Editor of ACS Nano Professor Il-Doo Kim)

Sound-based Touch Input Technology for Smart Table..

(from left: MS candidate Anish Byanjankar, Research Assistant Professor Hyosu Kim and Professor Insik Shin) Time passes so quickly, especially in the morning. Your hands are so busy brushing your teeth and checking the weather on your smartphone. You might wish that your mirror could turn into a touch screen and free up your hands. That wish can be achieved very soon. A KAIST team has developed a smartphone-based touch sound localization technology to facilitate ubiquitous interactions, turning objects like furniture and mirrors into touch input tools. This technology analyzes touch sounds generated from a user’s touch on a surface and identifies the location of the touch input. For instance, users can turn surrounding tables or walls into virtual keyboards and write lengthy e-mails much more conveniently by using only the built-in microphone on their smartphones or tablets. Moreover, family members can enjoy a virtual chessboard or enjoy board games on their dining tables. Additionally, traditional smart devices such as smart TVs or mirrors, which only provide simple screen display functions, can play a smarter role by adding touch input function support (see the image below). Figure 1.Examples of using touch input technology: By using only smartphone, you can use surrounding objects as a touch screen anytime and anywhere. The most important aspect of enabling the sound-based touch input method is to identify the location of touch inputs in a precise manner (within about 1cm error). However, it is challenging to meet these requirements, mainly because this technology can be used in diverse and dynamically changing environments. Users may use objects like desks, walls, or mirrors as touch input tools and the surrounding environments (e.g. location of nearby objects or ambient noise level) can be varied. These environmental changes can affect the characteristics of touch sounds. To address this challenge, Professor Insik Shin from the School of Computing and his team focused on analyzing the fundamental properties of touch sounds, especially how they are transmitted through solid surfaces. On solid surfaces, sound experiences a dispersion phenomenon that makes different frequency components travel at different speeds. Based on this phenomenon, the team observed that the arrival time difference (TDoA) between frequency components increases in proportion to the sound transmission distance, and this linear relationship is not affected by the variations of surround environments. Based on these observations, Research Assistant Professor Hyosu Kim proposed a novel sound-based touch input technology that records touch sounds transmitted through solid surfaces, then conducts a simple calibration process to identify the relationship between TDoA and the sound transmission distance, finally achieving accurate touch input localization. The accuracy of the proposed system was then measured. The average localization error was lower than about 0.4 cm on a 17-inch touch screen. Particularly, it provided a measurement error of less than 1cm, even with a variety of objects such as wooden desks, glass mirrors, and acrylic boards and when the position of nearby objects and noise levels changed dynamically. Experiments with practical users have also shown positive responses to all measurement factors, including user experience and accuracy. Professor Shin said, “This is novel touch interface technology that allows a touch input system just by installing three to four microphones, so it can easily turn nearby objects into touch screens.” The proposed system was presented at ACM SenSys, a top-tier conference in the field of mobile computing and sensing, and was selected as a best paper runner-up in November 2018. (The demonstration video of the sound-based touch input technology)

KAIST Mechanical Engineering department promotiona..

Crystal size of organic semiconductors can be cont..

(from left: MS cadidate Jeong-Chan Lee, Professor Steve Park and PhD candidate Jin-Oh Kim) A KAIST research team led by Professor Steve Park from the Department of Materials Science and Engineering Recently, solution-processable organic semiconductors are being highlighted for their potential application in printed electronics, becoming a feasible technique to fabricate large-area flexible thin film at a low cost. The field-effect mobility of small-molecule organic semiconductors is dependent on the crystallinity, crystal orientation, and crystal size. A variety of solution-based coating techniques, such as ink-jet printing, dip-coating, and solution shearing have been developed to control the crystallinity and crystal orientation, but a method for developing techniques to increase the crystal size of organic semiconductors is still needed. To overcome this issue, the research team developed an inorganic polymer micropillar-based solution shearing system to increase the crystal size of an organic semiconductor with pillar size. Using this technique, the crystallization process of organic semiconductors can be controlled precisely, and therefore large-area organic semiconductor thin film with controlled crystallinity can be fabricated. A variety of solution-based coating techniques cannot control the fluid-flow of solutions appropriately, so the solvent evaporates randomly onto the substrate, which has difficulty in the fabrication of organic semiconductor thin film with a large crystal size. The research team integrated inorganic polymer microstructures into the solution shearing blade to solve this issue. The inorganic polymer can easily be microstructured via conventional molding techniques, has high mechanical durability, and organic solvent resistance. Using the inorganic polymer-based microstructure blade, the research team controlled the size of small molecule organic semiconductors by tuning the shape and dimensions of the microstructure. The microstructures in the blade induce the sharp curvature regions in the meniscus line that formed between the shearing blade and the substrate, and therefore nucleation and crystal growth can be regulated. Hence, the research team fabricated organic semiconductor thin-film with large crystals, which increases the field-effect mobility. The research team also demonstrated a solution shearing process on a curved surface by using a flexible inorganic polymer-based shearing blade, which expands the applicability of solution shearing. Professor Park said, “Our new solution shearing system can control the crystallization process precisely during solvent evaporation.” He added, “This technique adds another key parameter that can be utilized to tune the property of thin films and opens up a wide variety of new applications. The results of this work entitled “Inorganic Polymer Micropillar-Based Solution Shearing of Large-Area Organic Semiconductor Thin Films with Pillar-Size-Dependent Crystal Size” was published in the July 2018 issue of Advanced Materials as a cover article. Figure 1. Cover article of the July 2018 Issue of Advanced Materials Figure 2. Chemical structure of inorganic polymer (AHPCS) and the fabrication process of a microstructured AHPCS shearing blade. Figure 3.The increasing trend of organic semiconductor crystal size with increasing the microstructure dimension.