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Novel Via-Hole-Less Multilevel Metal Interconnection Methods
Forming reliable multi-level metal interconnections is a key technology for integrating devices into organic integrated circuits (ICs). The conventional approach, called “via-hole,” locally removes the insulator and utilizes metal interconnects through the holes. Due to the high sensitivity of organic materials to chemical solvents, heat, and photo-radiation used in conventional “via-hole” methods, alternative printing methods or laser drilling methods have been developed. However, finding a reliable and practical metal interconnection for organic ICs is still challenging. The research team of KAIST Professor Sung Gap Im and Postech Professor Kim Jae-Joon reported a new interconnection method that does not require via-hole formation, “via-hole-less metal interconnection,” in Nature Communications on June 3. Metal electrodes in different layers can be isolated from each other by patterned dielectric layers, where they then can be interconnected to others in the open area where the dielectric layer is not present. See the images below. Vapor phase deposition and in-situ patterning of dielectric layer using iCVD (initiated chemical vapor deposition), used in the “via-hole-less” method, ensure a damage-free process for organic semiconductor materials and result in outstanding performance of the organic devices as multilevel metal interconnects are reliably formed. The team successfully demonstrated three-dimensional (3D) stacking of five organic transistors and integrated circuits using the proposed via-hole-less interconnect method. See the image below. Vapor phase deposition and in-situ patterning of dielectric layer using iCVD (initiated chemical vapor deposition), used in the “via-hole-less” method, ensure a damage-free process for organic semiconductor materials and result in outstanding performance of the organic devices as multilevel metal interconnects are reliably formed. The team successfully demonstrated three-dimensional (3D) stacking of five organic transistors and integrated circuits using the proposed via-hole-less interconnect method. See the image below. Professor Kim explained, “Our proposed via-hole-less interconnect method using a selectively patterned dielectric overcomes the limitations of the previous time-consuming, one-by-one via-hole formation process and provides reliable methods for creating metal interconnects in organic ICs. We expect the via-hole-less scheme to bring advances to organic IC technology.”
2019.06.18
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Play Games With No Latency
One of the most challenging issues for game players looks to be resolved soon with the introduction of a zero-latency gaming environment. A KAIST team developed a technology that helps game players maintain zero-latency performance. The new technology transforms the shapes of game design according to the amount of latency. Latency in human-computer interactions is often caused by various factors related to the environment and performance of the devices, networks, and data processing. The term ‘lag’ is used to refer to any latency during gaming which impacts the user’s performance. Professor Byungjoo Lee at the Graduate School of Culture Technology in collaboration with Aalto University in Finland presented a mathematical model for predicting players' behavior by understanding the effects of latency on players. This cognitive model is capable of predicting the success rate of a user when there is latency in a 'moving target selection' task which requires button input in a time constrained situation. The model predicts the players’ task success rate when latency is added to the gaming environment. Using these predicted success rates, the design elements of the game are geometrically modified to help players maintain similar success rates as they would achieve in a zero-latency environment. In fact, this research succeeded in modifying the pillar heights of the Flappy Bird game, allowing the players to maintain their gaming performance regardless of the added latency. Professor Lee said, "This technique is unique in the sense that it does not interfere with a player's gaming flow, unlike traditional methods which manipulate the game clock by the amount of latency. This study can be extended to various games such as reducing the size of obstacles in the latent computing environment.” This research, in collaboration with Dr. Sunjun Kim from Aalto University and led by PhD candidate Injung Lee, was presented during the 2019 CHI Conference on Human Factors in Computing Systems last month in Glasgow in the UK. This research was supported by the National Research Foundation of Korea (NRF) (2017R1C1B2002101, 2018R1A5A7025409), and the Aalto University Seed Funding Granted to the GamerLab respectively. Figure 1. Overview of Geometric Compensation Publication: Injung Lee, Sunjun Kim, and Byungjoo Lee. 2019. Geometrically Compensating Effect of End-to-End Latency in Moving-Target Selection Games. In Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems (CHI’19) . ACM, New York, NY, USA, Article 560, 12 pages. https://doi.org/10.1145/3290605.3300790 Video Material: https://youtu.be/TTi7dipAKJs Profile: Prof. Byungjoo Lee, MD, PhD byungjoo.lee@kaist.ac.kr http://kiml.org/ Assistant Professor Graduate School of Culture Technology (CT) Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon 34141, Korea Profile: Injung Lee, PhD Candidate edndn@kaist.ac.kr PhD Candidate Interactive Media Lab Graduate School of Culture Technology (CT) Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon 34141, Korea Profile: Postdoc. Sunjun Kim, MD, PhD kuaa.net@gmail.com Postdoctoral Researcher User Interfaces Group Aalto University https://www.aalto.fi Espoo 02150, Finland (END)
2019.06.11
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Early Genome Catastrophes Can Cause Non-Smoking Lung Cancer
Some teenagers harbor catastrophic changes to their genomes that can lead to lung cancer later on in life, even if they never smoke (Professor Young Seok Ju at the Graduate School of Medical Science and Engineering) Catastrophic rearrangements in the genome occurring as early as childhood and adolescence can lead to the development of lung cancer in later years in non-smokers. This finding, published in Cell, helps explain how some non-smoking-related lung cancers develop. Researchers at KAIST, Seoul National University and their collaborators confirmed that gene fusions in non-smokers mostly occur early on, sometimes as early as childhood or adolescence, and on average about three decades before cancer is diagnosed. The study showed that these mutant lung cells, harboring oncogenic seeds, remain dormant for several decades until a number of further mutations accumulate sufficiently for progression into cancer. This is the first study to reveal the landscape of genome structural variations in lung adenocarcinoma. Lung cancer is the leading cause of cancer-related deaths worldwide, and lung adenocarcinoma is its most common type. Most lung adenocarcinomas are associated with chronic smoking, but about a fourth develop in non-smokers. Precisely what happens in non-smokers for this cancer to develop is not clearly understood. Researchers analyzed the genomes of 138 lung adenocarcinoma patients, including smokers and non-smokers, with whole-genome sequencing technologies. They explored DNA damage that induced neoplastic transformation. Lung adenocarcinomas that originated from chronic smoking, referred to as signature 4-high (S4-high) cancers in the study, showed several distinguishing features compared to smoking-unrelated cancers (S4-low). People in the S4-high group were largely older, men and had more frequent mutations in a cancer-related gene called KRAS. Cancer genomes in the S4-high group were hypermutated with simple mutational classes, such as the substitution, insertion, or deletion of a single base, the building block of DNA. But the story was very different in the S4-low group. Generally, mutational profiles in this group were much more silent than the S4-high group. However, all cancer-related gene fusions, which are abnormally activated from the merging of two originally separate genes, were exclusively observed in the S4-low group. The patterns of genomic structural changes underlying gene fusions suggest that about three in four cases of gene fusions emerged from a single cellular crisis causing massive genomic fragmentation and subsequent imprecise repair in normal lung epithelium. Most strikingly, these major genomic rearrangements, which led to the development of lung adenocarcinoma, are very likely to be acquired decades before cancer diagnosis. The researchers used genomic archaeology techniques to trace the timing of when the catastrophes took place. Researchers started this study seven years ago when they discovered the expression of the KIF5B-RET gene fusion in lung adenocarcinoma for the first time. Professor Young-Seok Ju, co-lead author from the Graduate School of Medical Science and Engineering at KAIST says, “It is remarkable that oncogenesis can begin by a massive shattering of chromosomes early in life. Our study immediately raises a new question: What induces the mutational catastrophe in our normal lung epithelium.” Professor Young Tae Kim, co-lead author from Seoul National University says, “We hope this work will help us get one step closer to precision medicine for lung cancer patients.” The research team plans to further focus on the molecular mechanisms that stimulate complex rearrangements in the body, through screening the genomic structures of fusion genes in other cancer types. This study was supported by the National Research Foundation of Korea (NRF), Korea Health Industry Development Institute (KHIDI), Suh Kyungbae Foundation, the College of Medicine Research Foundations at Seoul National University and others. Figure. (Smoking-unrelated oncogenesis of lung cancers by gene fusions) Publication. Jake June-Koo Lee, Seongyeol Park et al., Tracing Oncogene Rearrangements in the Mutational History of Lung Adenocarcinoma Cell 177, June 13 2019, online publication ahead of print at May 30, 2019 https://doi.org/10.1016/j.cell.2019.05.013 Profile: Prof Young Seok Ju, MD, PhD ysju@kaist.ac.kr http://julab.kaist.ac.kr Associate Professor Graduate School of Medical Science and Engineering (GSMSE) Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141, Korea Profile: Prof Young Tae Kim, MD, PhD ytkim@snu.ac.kr Professor Seoul National University Cancer Research Institute Department of Thoracic and Cardiovascular Surgery Seoul National University Hospital Seoul 03080, Korea
2019.05.31
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Professor Cheol-Ho Jeong Honored with the DTU Lecturer of the Year
A KAIST alumnus and an associate professor at the Technical University of Denmark (DTU), Dr. Cheol-Ho Jeong was selected as the recipient of the Lecturer of the Year 2019 Award by DTU. Professor Jeong received his B.S., M.Sc., and Ph. D. degrees from KAIST’s Department of Mechanical Engineering in August 2007 under the supervision of Professor Jeong-Guon Ih, and has been serving as an assistant followed by associate professor at DTU’s Department of Electrical Engineering since October 2007. His research covers wide arrays of architectural acoustics, environmental acoustics, psychoacoustics, and structural acoustics. Every year, the students at DTU nominate one or two lecturer(s) of the year. The award celebrates and honors the selected lecturers for showing great commitment not only to education itself, but also to their communication and engagement with the students. This year, the DTU student union Polyteknisk Forening nominated Professor Jeong for his outstanding course evaluations for his excellent teaching over the years. One of the student testimonies for the award read, "Professor Jeong is one of the best teachers I have ever had at DTU. He is very humane and approachable." The awards ceremony was held on May 3 at DTU during the 2019 Annual Commemoration Party and Professor Jeong was warmly congratulated by the Crown Prince Couple of Denmark. The other award was given to Professor Robert Madsen from DTU’s Chemistry department. ©Photo and Quote: Ulrik Jantzen, Büro Jantzen, Camilla Christiane Hermann.
2019.05.30
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Professor Yim Decorated with the Chongjo Order of Merit
Professor Yong-Taek Yim from the Department of Mechanical Engineering was awarded the highest order of merit, the “Chongjo Keunjong Medal,” bestowed to public officials by the government in celebration of Invention Day on May 27. Professor Yim was recognized for his innovative achievements to increase royalty income by introducing an IP-based management system at the Korean Institute of Machinery & Materials. He served as the president of KIMM for three years from 2014. His idea led to new approaches to help explore diverse revenue creating sources such as dividend earnings and share sales, apart from simply relying on technology transfer fees. His efforts to disseminate the in-house R&D results also led to the foundation of six tech-based startups and spinoffs, which generated 11.2 billion KRW in sales. He also helped set up three spinoffs abroad. Professor Yim said, “I pushed employee invention as a new value creator at KIMM. I thank each and every researcher and staff member at KIMM who worked so hard to create such an innovative IP-based R&D environment.”
2019.05.28
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'Think Out of the Box,' Team Circos Wins the P4G Innovation Sprint
<The winning team of the P4G Innovation Sprint poses with the Crown Prince of Denmark (sixth from the left in the first row) and President Shin (fifth from the left in the first row) during the awarding ceremony.> Team Circos from KAIST and Denmark made a new sustainable business model for Hempel, a global coating supplier group in Denmark, and won the first prize at the P4G (the Partnership for Green Growth and Global Goals) Innovation Sprint held at KAIST’s Seoul campus on May 22. The six-member team was awarded one million KRW in prize money by the Crown Prince of Denmark. Two of winning team members have the privilege of traveling to visit Hempel in Denmark. The winning team thought outside the box, inspired by box wine which reduced the sales price from traditional bottled wine. Six teams made up of members from different academic disciplines spent two nights and three days brainstorming ways to resolve the challenges of corporations such as Velux and Hempel from Denmark and SK from Korea. The P4G Innovation Sprint is one of the events co-hosted by KAIST and Technological University of Denmark in celebration of the 60th anniversary of diplomatic relations establishment between Denmark and Korea and the 8th anniversary of the Green Growth Alliance between the two countries. The Crown Prince Couple also made a royal visit to Korea in honor of the 60th anniversary celebration and Green Growth Alliance between the two countries. This Innovation Sprint aimed to develop young academics’ perspectives, skills, and talents for the next generation to better research the Sustainable Development Goals set by UN. Three teams made their final five-minute pitches before the Crown Prince and President Sung-Chul Shin and responded to questions from the four-member jury. The Crown Prince of Denmark and President Shin both agreed that the collaborative and convergent ideas will address global problems. The Crown Prince stressed in his congratulatory remarks the importance of partnership in this polarizing world to achieve sustainable improvements saying, “Partnerships are only possible to sustain through collaboration and hard work while staying curious, creative, and critical. " He also shared the special relationship with KAIST. His father-in-law Professor John Donaldson used to be a visiting professor of applied mathmatics at KAIST back in 2003. President Shin added, “Collaboration across boundaries is most critical for responding to these issues. In that sense, this P4G Innovation Sprint is a shining example for demonstrating the collaborative efforts between teammates from diverse disciplines. When we work together and build convergent ideas, we will be more innovative and go further.” <Winning team member Nicolai Thorball from DTU pitches at the final in the presence of the Crown Prince of Denmark and KAIST President Shin.> “The canned packaging in the paint industry results in 40 times more carbon emission in the course of production. However, when using aluminum packaging which is recyclable, the waste amount will be cut dramatically,” pitched Nicolai Thorball from DTU on exchange at Seoul National University. Nicolai, whose major is environmental engineering, is one of two Danish students including Thomsen Xandra Flyvbjerg from the University of Southern Denmark. Flyvbjergy, majoring in business, is now on exchange at Sungkynkwan University. “I am very glad to have the chance to understand the concept of the circular economy and green growth at the sprint. It was also very challenging to make ideation from so many ideas brainstormed,” said Dong-Eun Lee, a KAIST undergraduate from the Department of Biological Sciences. He said that he learned a lot from his two other teammates who are from the Program of Green Business & Policy at KAIST College of Business, Jae-Hee Park and Kyung-Hyun Kim. Juho Park majoring in mechanical engineering at KAIST was one of the team. Circos’ solution for a sustainable model received acclaim from the jury members. DTU Senior Vice President Marianne Thellerson, one of jurors, claimed their model has very high market feasibility, saying, “Their idea could be commercialized right now into the market.” Professor Hee-Kyung Park from KAIST who helped participants’ ideation as one of four mentors said, “The winning team perfectly met all the components of the evaluation criteria, Solution, Acceleration, and Pitch.” At this sprint, 10 students from Denmark and 29 KAIST students were divided into 6 teams and given the challenges of three companies. The Danish window facility company Velux presented its future glass window system and the paint company Hempel their circular economic new business model. SK challenged the students to help it become a global clean energy solution company. The event was based on a hacker blueprint that found the optimal solution to the topics proposed.
2019.05.23
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Professor Yim Appointed As Associate Editor of Nuclear Technology
Professor Man-Sung Yim from the Department of Nuclear and Quantum Engineering was appointed as the associate editor (for the Asian region) of Nuclear Technology ― a leading international research journal of the American Nuclear Society. Professor Yim will serve his term for three years from May 2019. The American Nuclear Society, established in 1954, is comprised of more than 11,000 global members and aims to advance nuclear science, engineering, and technology while supporting the peaceful and beneficial applications of nuclear energy. Since its first publication in 1971, Nuclear Technology has been a representative journal of the society, reporting state-of-the-art information on all phases of the practical applications of nuclear technology. Professor Yim is being recognized worldwide for his pioneering nuclear education, research, and policy studies in the fields of non-proliferation, safeguards for severe accident management, and waste management. He served as the head professor of the Department of Nuclear and Quantum Engineering and established the Nonproliferation Education and Research Center (NEREC) at KAIST. Professor Yim remarked, “Asia has an important role to play at the forefront of the world’s nuclear research considering that nuclear development is most actively being carried out in the Asian region these days.”
2019.05.17
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Engineered Microbial Production of Grape Flavoring
(Image 1: Engineered bacteria that produce grape flavoring.) Researchers report a microbial method for producing an artificial grape flavor. Methyl anthranilate (MANT) is a common grape flavoring and odorant compound currently produced through a petroleum-based process that uses large volumes of toxic acid catalysts. Professor Sang-Yup Lee’s team at the Department of Chemical and Biomolecular Engineering demonstrated production of MANT, a naturally occurring compound, via engineered bacteria. The authors engineered strains of Escherichia coli and Corynebacetrium glutamicum to produce MANT through a plant-based engineered metabolic pathway. The authors tuned the bacterial metabolic pathway by optimizing the levels of AAMT1, the key enzyme in the process. To maximize production of MANT, the authors tested six strategies, including increasing the supply of a precursor compound and enhancing the availability of a co-substrate. The most productive strategy proved to be a two-phase extractive culture, in which MANT was extracted into a solvent. This strategy produced MANT on the scale of 4.47 to 5.74 grams per liter, a significant amount, considering that engineered microbes produce most natural products at a scale of milligrams or micrograms per liter. According to the authors, the results suggest that MANT and other related molecules produced through industrial processes can be produced at scale by engineered microbes in a manner that would allow them to be marketed as natural one, instead of artificial one. This study, featured at the Proceeding of the National Academy of Sciences of the USA on May 13, was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biorefineries from the Ministry of Science and ICT. (Image 2. Overview of the strategies applied for the microbial production of grape flavoring.)
2019.05.15
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Education Innovation Day Reaffirms Rewarding of Excellence
Professors Tae-Eog Lee and Il-Chul Moon from the Department of Industrial & Systems Engineering received the Linkgenesis Best Teacher Award and the Soo-Young Lee Teaching Innovation Award on May 10. They were each awarded with 10 million KRW in prize money during the Education Innovation Day ceremony held at the Chung Kun-mo conference hall. The award was endowed by KAIST Alumni Scholarship Chairman Hyung-Kyu Lim and KAIST Foundation Chairman Soo-Young Lee to support the innovation initiative and acknowledge faculty members who made significant contributions to educational innovation and benefited the general public though their innovations. “KAIST’s vision for excellence and commitment to innovation is a game changer. Educational innovation is one of five pillars of Vision 2031, and it is our priority to foster critical and creative thinking students,” said President Sung-Chul Shin at the ceremony. All the awardees made presentation on their innovative projects and shared their ideas on better pedagogical methodology for next generation. Professor Lee, dean of the KAIST Academy and the head of the Center for Excellence in Learning & Teaching was recognized for his contribution to enhancing educational quality through innovative learning and teaching methodology development. He has set up an Education 3.0 Initiative, an online education platform for flipped learning at KAIST. Professor Moon also upgraded the online education platform to the 4.0 version and extended KAIST’s massive online courses through KOOC framework. This open platform offers more than 62 courses, with more than 170 thousand users registered since 2014. Professor Song-Hong Park from the Department of Bio and Brain Engineering and Professor Jae-Woo Lee from the Department of Chemical and Biomolecular Engineering also won the Excellence Award.
2019.05.10
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Professor Ji-Hyun Lee Awarded the Sasada Prize
Professor Ji-Hyun Lee from the Graduate School of Culture Technology was awarded the Sasada Prize during the 24th annual Conference of Computer-Aided Architectural Design Research in Asia (CAADRIA) held in Wellington, New Zealand on April 15. The Sasada Award honors the late Professor Tsuyoshi Sasada (1941-2005), the former Professor of Osaka University and co-founder and fellow of CAADRIA. It is given to an individual who has contributed to the next generation of researchers and academics, to the wider profession and practice in computer-aided design and research, and has earned recognition in the academic community. Professor Lee was recognized for her development of CAAD (Computer-Aided Architectural Design) through her research work on the land price precision system using case-based reasoning. Her research team proposed a model for estimating the average apartment price in an administrative district after collecting 40 variables from the six major Korean cities, excluding Seoul and Ulsan. Their follow-up studies showed the possibility of replacing existing experts’ predictions. Professor Lee has been steadily researching for 20 years on case-based reasoning (CBR), a field of artificial intelligence, and has published more than 40 papers in the field of CBR. Meanwhile, the CAAD Future 2019 event will be held at KAIST in June.
2019.04.23
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Distinguished Professor Sang Yup Lee Honored with the 23rd NAEK Award
(Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering) Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering was honored to be the laureate of the 23rd NAEK Award. The NAEK (National Academy of Engineering of Korea) Award was instituted in 1997 to honor and recognize engineers who have made significant contributions to the development of the engineering and technology field at universities, industries, and institutions. Every year, it is conferred to only one person who has achieved original and world-leading research that has led to national development. Distinguished Professor Lee is a pioneering scholar of the field of systems metabolic engineering and he was recognized for his significant achievements in the biochemical industry by developing novel microbial bioprocesses. In particular, he is globally renowned for biological plastic synthesis, making or decomposing polymers with microorganisms instead of using fossil resources. He has produced numerous high-quality research breakthroughs in metabolic and systems engineering. In 2016, he produced an easily degradable plastic with Escherichia coli (E. coli). In 2018, he successfully produced aromatic polyesters, the main material for PET (poly ethylene terephthalate) from E. coli strains. He also identified microorganism structures for PET degradation and improved its degradability with a novel variant. His research was ranked number one in the research and development division of Top Ten Science and Technology News 2018 announced by Korean Federation of Science & Technology Societies. He is one of highly cited researchers (HCR) ranked in the top 1% by citations for their field by the Clarivate Analytics.
2019.03.21
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The Future Mobility of the Year 2019
KAIST announced the Future Mobility of the Year (FMOTY) 2019. The winners are Volvo 360C, Toyota e-Palette, and Toyota Concept-i WALK. FMOTY are the first awards that recognizes concept cars that exhibit innovative services and practical transportation technology in three categories: private mobility, public and commercial mobility, and personal mobility. Figure 1. The winner in the private mobility division, the Volvo 360C In the private mobility division, the award went to the Volvo 360C. With targeted routes of roughly 186 miles, this vehicle has an ambitious service goal to replace airplanes by traveling these routes with great comfort. Goro Okazaki, a journalist with Car and Driver Japan, said, “The Volvo 360C clearly shows how highly personalized autonomous driving can change the future.” Figure 2. The winner in the public mobility division, the Toyota e-Palette The Toyota e-Palette was the winning car in commercial mobility division. This vehicle provides the best solution as a mobile service platform by transforming itself into mobile hospitals, hotels, stores and food trucks. Carlo Calderón, a journalist for Autopista Spain, said, “It has a great strength in remodeling its indoor and outdoor spaces according to various commercial uses.” Figure 3. The winner in the personal mobility division, the Toyota Concept-i WALK In the personal mobility division, the award went to the Toyota Concept-i WALK. It was recognized for having an exquisite user environment and artificial intelligent agent, along with an excellent completion. Jun Miao, a journalist with MJ CarShow China, said, “It is aesthetically pleasing. Beyond the upright control of conventional personal mobility, it allows agile control with a joystick.” FMOTY conducted a screening process for 45 concept cars over three months and 16 renowned automotive experts from 11 countries participated as judges for this award, including Editor in Chief of BBC Top Gear Magazine Charlie Turner and European Bureau Chief of Automobile Magazine Georg Kacher. The judges said that FMOTY was born to propose a new aspect of future mobility, and in terms of evaluating technical and social values of concept cars, FMOTY carries great significance. Kyung-soo Kim, Dean of the Cho Chun Shik Graduate School of Green Transportation said, “Globally renowned experts in the automotive field participated as judges to elevate the prestige and fairness of the awards. KAIST members were excluded from the entire judging process. I believe that the FMOTY Awards will expand public attention from the present to the future.” Details can be found on the official website of FMOTY ( www.fmoty.org ).
2019.03.11
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