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KAIST researchers find sleep delays more prevalent in countries of particular culture than others
Sleep has a huge impact on health, well-being and productivity, but how long and how well people sleep these days has not been accurately reported. Previous research on how much and how well we sleep has mostly relied on self-reports or was confined within the data from the unnatural environments of the sleep laboratories. So, the questions remained: Is the amount and quality of sleep purely a personal choice? Could they be independent from social factors such as culture and geography? < From left to right, Sungkyu Park of Kangwon National University, South Korea; Assem Zhunis of KAIST and IBS, South Korea; Marios Constantinides of Nokia Bell Labs, UK; Luca Maria Aiello of the IT University of Copenhagen, Denmark; Daniele Quercia of Nokia Bell Labs and King's College London, UK; and Meeyoung Cha of IBS and KAIST, South Korea > A new study led by researchers at Korea Advanced Institute of Science and Technology (KAIST) and Nokia Bell Labs in the United Kingdom investigated the cultural and individual factors that influence sleep. In contrast to previous studies that relied on surveys or controlled experiments at labs, the team used commercially available smartwatches for extensive data collection, analyzing 52 million logs collected over a four-year period from 30,082 individuals in 11 countries. These people wore Nokia smartwatches, which allowed the team to investigate country-specific sleep patterns based on the digital logs from the devices. < Figure comparing survey and smartwatch logs on average sleep-time, wake-time, and sleep durations. Digital logs consistently recorded delayed hours of wake- and sleep-time, resulting in shorter sleep durations. > Digital logs collected from the smartwatches revealed discrepancies in wake-up times and sleep-times, sometimes by tens of minutes to an hour, from the data previously collected from self-report assessments. The average sleep-time overall was calculated to be around midnight, and the average wake-up time was 7:42 AM. The team discovered, however, that individuals' sleep is heavily linked to their geographical location and cultural factors. While wake-up times were similar, sleep-time varied by country. Individuals in higher GDP countries had more records of delayed bedtime. Those in collectivist culture, compared to individualist culture, also showed more records of delayed bedtime. Among the studied countries, Japan had the shortest total sleep duration, averaging a duration of under 7 hours, while Finland had the longest, averaging 8 hours. Researchers calculated essential sleep metrics used in clinical studies, such as sleep efficiency, sleep duration, and overslept hours on weekends, to analyze the extensive sleep patterns. Using Principal Component Analysis (PCA), they further condensed these metrics into two major sleep dimensions representing sleep quality and quantity. A cross-country comparison revealed that societal factors account for 55% of the variation in sleep quality and 63% of the variation in sleep quantity. Countries with a higher individualism index (IDV), which placed greater emphasis on individual achievements and relationships, had significantly longer sleep durations, which could be attributed to such societies having a norm of going to bed early. Spain and Japan, on the other hand, had the bedtime scheduled at the latest hours despite having the highest collectivism scores (low IDV). The study also discovered a moderate relationship between a higher uncertainty avoidance index (UAI), which measures implementation of general laws and regulation in daily lives of regular citizens, and better sleep quality. Researchers also investigated how physical activity can affect sleep quantity and quality to see if individuals can counterbalance cultural influences through personal interventions. They discovered that increasing daily activity can improve sleep quality in terms of shortened time needed in falling asleep and waking up. Individuals who exercise more, however, did not sleep longer. The effect of exercise differed by country, with more pronounced effects observed in some countries, such as the United States and Finland. Interestingly, in Japan, no obvious effect of exercise could be observed. These findings suggest that the relationship between daily activity and sleep may differ by country and that different exercise regimens may be more effective in different cultures. This research published on the Scientific Reports by the international journal, Nature, sheds light on the influence of social factors on sleep. (Paper Title "Social dimensions impact individual sleep quantity and quality" Article number: 9681) One of the co-authors, Daniele Quercia, commented: “Excessive work schedules, long working hours, and late bedtime in high-income countries and social engagement due to high collectivism may cause bedtimes to be delayed.” Commenting on the research, the first author Shaun Sungkyu Park said, "While it is intriguing to see that a society can play a role in determining the quantity and quality of an individual's sleep with large-scale data, the significance of this study is that it quantitatively shows that even within the same culture (country), individual efforts such as daily exercise can have a positive impact on sleep quantity and quality." "Sleep not only has a great impact on one’s well-being but it is also known to be associated with health issues such as obesity and dementia," said the lead author, Meeyoung Cha. "In order to ensure adequate sleep and improve sleep quality in an aging society, not only individual efforts but also a social support must be provided to work together," she said. The research team will contribute to the development of the high-tech sleep industry by making a code that easily calculates the sleep indicators developed in this study available free of charge, as well as providing the benchmark data for various types of sleep research to follow.
2023.07.07
View 4854
2023 Global Entrepreneurship Summer School in Silicon Valley Successfully Concluded
< 2023 Silicon Valley Global Entrepreneurship Summer School Participants > The 2023 KAIST Global Entrepreneurship Summer School (GESS) was successfully held. Co-hosted by the Center for Global Strategies and Planning (GSP) (Director Man-Sung Yim) and the Startup KAIST (Director Hyeonmin Bae), the 2023 KAIST GESS was the second one of the summer programs, repeating the Silicon Valley global entrepreneurship bootcamp of 2022 (2022 GESC), based on industry-academia collaboration. This program was designed to provide students with the opportunity to visit Silicon Valley, the global hub of entrepreneurship, and personally experience the Silicon Valley culture while developing human networks that would serve as a foundation for their overseas startup development. A total of 20 participants were selected earlier this year, including potential KAISTian entrepreneurs and early-stage entrepreneurs from KAIST within one year of incorporation. In particular, a number of foreign students of various nationalities such as Vietnam, Azerbaijan, Honduras, Indonesia, Philippines, and Kazakhstan, increased significantly, demonstrating the enthusiasm for entrepreneurship across national boundaries along with the program's growing international status. This year's event was also open to 20 Impact MBA and Social Entrepreneur (SE) students from KAIST's College of Business for the Silicon Valley program. For the past two months, the participants have trained on business model development and pitching at KAIST's main campus in Daejeon. From June 21st to the 30th, they visited the campuses of leading universities, such as, Stanford University, UC Santa Cruz, and UC Berkeley, as well as KOTRA Silicon Valley Trade Center (Manager Hyoung il Kim), and local alumni companies and Apple company to experience the global technology startups. The start-ups by KAIST alums including B Garage (CEO Aiden Kim), ImpriMed (CEO Sungwon Lim), Medic Life Sciences (CEO Kyuho Han), and VESSL AI (CEO Jaeman Ahn) participated in the program and gave lectures and company tours to inspire the participants to have passion to take on the entrepreneurial endeavors and challenges. On the last day, the participants gave presentations on their team’s business items in front of local venture capitalists in Silicon Valley. After receiving continuous coaching from Silicon Valley's professional accelerators through remote video conferencing and face-to-face mentoring for the last two months, the participants developed their business models and presented their creative and innovative ideas, revealing their potential as future global entrepreneurs. At the final competition, Team Sparky that developed “Snoove” won the first prize. Snoove is a scientifically-proven mattress accessory that applies mild vibration to the mattress to aid users in achieving better sleep, a method previously used to soothe infants. < GESS Pitching Day Presentation > Kevin Choi from the Team Sparky said, "Seeing and experiencing the realities of entrepreneurship in Silicon Valley, a global startup scene, made me think about the importance of unlearning, challenging, and failing to be a global entrepreneur who contributes to our society." Man-Sung Yim, the Associate Vice President of the International Office, who organized the event added, "Through this experience, we expect KAIST students to grow to become global leaders who would create global values and enhance the international reputation of our university." Meanwhile, the GSP and Startup KAIST commented that they will to continue to develop the KAIST GESS program to foster prospective entrepreneurs who can compete in the global market based on the success of this program.
2023.07.05
View 7197
KAIST gearing up to train physician-scientists and BT Professionals joining hands with Boston-based organizations
KAIST (President Kwang Hyung Lee) announced on the 29th that it has signed MOUs with Massachusetts General Hospital, a founding member of the Mass General Brigham health care system and a world-class research-oriented hospital, and Moderna, a biotechnology company that developed a COVID-19 vaccine at the Langham Hotel in Boston, MA, USA on the morning of April 28th (local time). The signing ceremony was attended by officials from each institution joined by others headed by Minister LEE Young of the Korean Ministry of SMEs and Startups (MSS), and Commissioner LEE Insil of the Korean Intellectual Property Office. < Photo 1. Photo from the Signing of MOU between KAIST-Harvard University Massachusetts General Hospital and KAIST-Moderna > Mass General is the first and largest teaching hospital of Harvard Medical School in Boston, USA, and it is one of the most innovative hospitals in the world being the alma mater of more than 13 Nobel Prize winners and the home of the Mass General Research Institute, the world’s largest hospital-based research program that utilizes an annual research budget of more than $1.3 billion. KAIST signed a general agreement to explore research and academic exchange with Mass General in September of last year and this MOU is a part of its follow-ups. Mass General works with Harvard and the Massachusetts Institute of Technology (MIT), as well as local hospitals, to support students learn the theories of medicine and engineering, and gain rich clinical research experience. Through this MOU, KAIST will explore cooperation with an innovative ecosystem created through the convergence of medicine and engineering. In particular, KAIST’s goal is to develop a Korean-style training program and implement a differentiated educational program when establishing the science and technology-oriented medical school in the future by further strengthening the science and engineering part of the training including a curriculum on artificial intelligence (AI) and the likes there of. Also, in order to foster innovative physician-scientists, KAIST plans to pursue cooperation to develop programs for exchange of academic and human resources including programs for student and research exchanges and a program for students of the science and technology-oriented medical school at KAIST to have a chance to take part in practical training at Mass General. David F.M. Brown, MD, Mass General President, said, “The collaboration with KAIST has a wide range of potentials, including advice on training of physician-scientists, academic and human resource exchanges, and vitalization of joint research by faculty from both institutions. Through this agreement, we will be able to actively contribute to global cooperation and achieve mutual goals.” Meanwhile, an MOU between KAIST and Moderna was also held on the same day. Its main focus is to foster medical experts in cooperation with KAIST Graduate School of Medical Science and Engineering (GSMSE), and plans to cooperate in various ways in the future, including collaborating for development of vaccine and new drugs, virus research, joint mRNA research, and facilitation of technology commercialization. In over 10 years since its inception, Moderna has transformed from a research-stage company advancing programs in the field of messenger RNA (mRNA) to an enterprise with a diverse clinical portfolio of vaccines and therapeutics across seven modalities. The Company has 48 programs in development across 45 development candidates, of which 38 are currently in active clinical trials. “We are grateful to have laid a foundation for collaboration to foster industry experts with the Korea Advanced Institute of Science and Technology, a leader of science and technology innovation in Korea,” said Arpa Garay, Chief Commercial Officer, Moderna. “Based on our leadership and expertise in developing innovative mRNA vaccines and therapeutics, we hope to contribute to educating and collaborating with professionals in the bio-health field of Korea.“ President Kwang Hyung Lee of KAIST, said, “We deem this occasion to be of grave significance to be able to work closely with Massachusetts General Hospital, one of the world's best research-oriented hospitals, and Moderna, one of the most influential biomedical companies.” President Lee continued, "On the basis of the collaboration with the two institutions, we will be able to bring up qualified physician-scientists and global leaders of the biomedical business who will solve problems of human health and their progress will in turn, accelerate the national R&D efforts in general and diversify the industry."
2023.04.29
View 10317
KAIST Holds 2023 Commencement Ceremony
< Photo 1. On the 17th, KAIST held the 2023 Commencement Ceremony for a total of 2,870 students, including 691 doctors. > KAIST held its 2023 commencement ceremony at the Sports Complex of its main campus in Daejeon at 2 p.m. on February 27. It was the first commencement ceremony to invite all its graduates since the start of COVID-19 quarantine measures. KAIST awarded a total of 2,870 degrees including 691 PhD degrees, 1,464 master’s degrees, and 715 bachelor’s degrees, which adds to the total of 74,999 degrees KAIST has conferred since its foundation in 1971, which includes 15,772 PhD, 38,360 master’s and 20,867 bachelor’s degrees. This year’s Cum Laude, Gabin Ryu, from the Department of Mechanical Engineering received the Minister of Science and ICT Award. Seung-ju Lee from the School of Computing received the Chairman of the KAIST Board of Trustees Award, while Jantakan Nedsaengtip, an international student from Thailand received the KAIST Presidential Award, and Jaeyong Hwang from the Department of Physics and Junmo Lee from the Department of Industrial and Systems Engineering each received the President of the Alumni Association Award and the Chairman of the KAIST Development Foundation Award, respectively. Minister Jong-ho Lee of the Ministry of Science and ICT awarded the recipients of the academic awards and delivered a congratulatory speech. Yujin Cha from the Department of Bio and Brain Engineering, who received a PhD degree after 19 years since his entrance to KAIST as an undergraduate student in 2004 gave a speech on behalf of the graduates to move and inspire the graduates and the guests. After Cha received a bachelor’s degree from the Department of Nuclear and Quantum Engineering, he entered a medical graduate school and became a radiation oncology specialist. But after experiencing the death of a young patient who suffered from osteosarcoma, he returned to his alma mater to become a scientist. As he believes that science and technology is the ultimate solution to the limitations of modern medicine, he started as a PhD student at the Department of Bio and Brain Engineering in 2018, hoping to find such solutions. During his course, he identified the characteristics of the decision-making process of doctors during diagnosis, and developed a brain-inspired AI algorithm. It is an original and challenging study that attempted to develop a fundamental machine learning theory from the data he collected from 200 doctors of different specialties. Cha said, “Humans and AI can cooperate by humans utilizing the unique learning abilities of AI to develop our expertise, while AIs can mimic us humans’ learning abilities to improve.” He added, “My ultimate goal is to develop technology to a level at which humans and machines influence each other and ‘coevolve’, and applying it not only to medicine, but in all areas.” Cha, who is currently an assistant professor at the KAIST Biomedical Research Center, has also written Artificial Intelligence for Doctors in 2017 to help medical personnel use AI in clinical fields, and the book was selected as one of the 2018 Sejong Books in the academic category. During his speech at this year’s commencement ceremony, he shared that “there are so many things in the world that are difficult to solve and many things to solve them with, but I believe the things that can really broaden the horizons of the world and find fundamental solutions to the problems at hand are science and technology.” Meanwhile, singer-songwriter Sae Byul Park who studied at the KAIST Graduate School of Culture Technology will also receive her PhD degree. Natural language processing (NLP) is a field in AI that teaches a computer to understand and analyze human language that is actively being studied. An example of NLP is ChatGTP, which recently received a lot of attention. For her research, Park analyzed music rather than language using NLP technology. To analyze music, which is in the form of sound, using the methods for NLP, it is necessary to rebuild notes and beats into a form of words or sentences as in a language. For this, Park designed an algorithm called Mel2Word and applied it to her research. She also suggested that by converting melodies into texts for analysis, one would be able to quantitatively express music as sentences or words with meaning and context rather than as simple sounds representing a certain note. Park said, “music has always been considered as a product of subjective emotion, but this research provides a framework that can calculate and analyze music.” Park’s study can later be developed into a tool to measure the similarities between musical work, as well as a piece’s originality, artistry and popularity, and it can be used as a clue to explore the fundamental principles of how humans respond to music from a cognitive science perspective. Park began her Ph.D. program in 2014, while carrying on with her musical activities as well as public and university lectures alongside, and dealing with personally major events including marriage and childbirth during the course of years. She already met the requirements to receive her degree in 2019, but delayed her graduation in order to improve the level of completion of her research, and finally graduated with her current achievements after nine years. Professor Juhan Nam, who supervised Park’s research, said, “Park, who has a bachelor’s degree in psychology, later learned to code for graduate school, and has complete high-quality research in the field of artificial intelligence.” He added, “Though it took a long time, her attitude of not giving up until the end as a researcher is also excellent.” Sae Byul Park is currently lecturing courses entitled Culture Technology and Music Information Retrieval at the Underwood International College of Yonsei University. Park said, “the 10 or so years I’ve spent at KAIST as a graduate student was a time I could learn and prosper not only academically but from all angles of life.” She added, “having received a doctorate degree is not the end, but a ‘commencement’. Therefore, I will start to root deeper from the seeds I sowed and work harder as a both a scholar and an artist.” < Photo 2. From left) Yujin Cha (Valedictorian, Medical-Scientist Program Ph.D. graduate), Saebyeol Park (a singer-songwriter, Ph.D. graduate from the Graduate School of Culture and Technology), Junseok Moon and Inah Seo (the two highlighted CEO graduates from the Department of Management Engineering's master’s program) > Young entrepreneurs who dream of solving social problems will also be wearing their graduation caps. Two such graduates are Jun-seok Moon and Inah Seo, receiving their master’s degrees in social entrepreneurship MBA from the KAIST College of Business. Before entrance, Moon ran a café helping African refugees stand on their own feet. Then, he entered KAIST to later expand his business and learn social entrepreneurship in order to sustainably help refugees in the blind spots of human rights and welfare. During his master’s course, Moon realized that he could achieve active carbon reduction by changing the coffee alone, and switched his business field and founded Equal Table. The amount of carbon an individual can reduce by refraining from using a single paper cup is 10g, while changing the coffee itself can reduce it by 300g. 1kg of coffee emits 15kg of carbon over the course of its production, distribution, processing, and consumption, but Moon produces nearly carbon-neutral coffee beans by having innovated the entire process. In particular, the company-to-company ESG business solution is Moon’s new start-up area. It provides companies with carbon-reduced coffee made by roasting raw beans from carbon-neutral certified farms with 100% renewable energy, and shows how much carbon has been reduced in its making. Equal Table will launch the service this month in collaboration with SK Telecom, its first partner. Inah Seo, who also graduated with Moon, founded Conscious Wear to start a fashion business reducing environmental pollution. In order to realize her mission, she felt the need to gain the appropriate expertise in management, and enrolled for the social entrepreneurship MBA. Out of the various fashion industries, Seo focused on the leather market, which is worth 80 trillion won. Due to thickness or contamination issues, only about 60% of animal skin fabric is used, and the rest is discarded. Heavy metals are used during such processes, which also directly affects the environment. During the social entrepreneurship MBA course, Seo collaborated with SK Chemicals, which had links through the program, and launched eco-friendly leather bags. The bags used discarded leather that was recycled by grinding and reprocessing into a biomaterial called PO3G. It was the first case in which PO3G that is over 90% biodegradable was applied to regenerated leather. In other words, it can reduce environmental pollution in the processing and disposal stages, while also reducing carbon emissions and water usage by one-tenth compared to existing cowhide products. The social entrepreneurship MBA course, from which Moon and Seo graduated, will run in integration with the Graduate School of Green Growth as an Impact MBA program starting this year. KAIST plans to steadily foster entrepreneurs who will lead meaningful changes in the environment and society as well as economic values through innovative technologies and ideas. < Photo 3. NYU President Emeritus John Sexton (left), who received this year's honorary doctorate of science, poses with President Kwang Hyung Lee > Meanwhile, during this day’s commencement ceremony, KAIST also presented President Emeritus John Sexton of New York University with an honorary doctorate in science. He was recognized for laying the foundation for the cooperation between KAIST and New York University, such as promoting joint campuses. < Photo 4. At the commencement ceremony of KAIST held on the 17th, President Kwang Hyung Lee is encouraging the graduates with his commencement address. > President Kwang Hyung Lee emphasized in his commencement speech that, “if you can draw up the future and work hard toward your goal, the future can become a work of art that you create with your own hands,” and added, “Never stop on the journey toward your dreams, and do not give up even when you are met with failure. Failure happens to everyone, all the time. The important thing is to know 'why you failed', and to use those elements of failure as the driving force for the next try.”
2023.02.20
View 12861
KAIST confers Honorary Doctorate of Science on NYU President Emeritus John Edward Sexton
< Photo 1. NYU President Emeritus John Edward Sexton posing with KAIST President Kwang Hyung Lee holding the Honorary Doctorate at the KAIST Commencement Ceremony > KAIST (President Kwang Hyung Lee) announced that it conferred an honorary doctorate of science degree on NYU President Emeritus John Edward Sexton at the Commencement Ceremony held on the 17th. An official from KAIST explained, "KAIST is conferring an honorary doctorate for President Sexton's longstanding leadership in higher education, and for his contributions to the process of establishing the groundwork for collaboration with NYU through which KAIST is to become a leading global value-creating university." President Emeritus Sexton served as the president of NYU from 2002 to 2015, establishing two degree-granting campuses and several global academic sites of NYU around the world. Because of its steady rise in university rankings, such as its medical school earning the number two position in the United States, not only has NYU joined the ranks of first-class universities, but it has also achieved remarkable growth, with the number of students increasing dramatically from 29,000 to 60,000. In addition, during his tenure as president at NYU, President Emeritus Sexton successfully expanded fundraising to support the University’s academic goals. During his 14-year tenure as president, he organized initiatives such as 'Raise $1 Million Every Day' and 'Call to Action' to raise $4.9 billion in donations, the largest in NYU history to date. President Emeritus Sexton is famous for teaching full time even during his presidential tenure and for the anecdotes about his special care for students, addressing the school members as “family”. In particular, he is famous for giving hugs to all graduates at the commencement ceremony. Minister Park Jin of the Ministry of Foreign Affairs of Korea, who graduated from NYU School of Law in 1999 with a Master of Studies in Law, is one of the graduates who received President Sexton's hug. President Emeritus Sexton, born in 1942, visited KAIST on the 17th to receive the honorary doctorate and to encourage the expedited development of the KAIST-NYU Joint Campus, for which he helped lay the foundation. President Emeritus Sexton said, "I like the slogan, 'Onward and upward together,'" and added, "I look forward to having the two universities achieve their shared vision of becoming the world-class universities together through cooperation to establish the KAIST-NYU Joint Campus." < Photo 2. NYU President Emeritus John Edward Sexton giving the acceptance speech at the KAIST Commencement Ceremony > The US Ambassador to Korea, the Honorable Philip Goldberg, also attended the commencement ceremony at KAIST to congratulate President Emeritus Sexton on the conferment of the honorary doctorate. Ambassador Goldberg has been serving as the US Ambassador to Korea since July of last year. President Kwang Hyung Lee said, “President Emeritus Sexton was a president best described as an innovator who promoted diversity in education and pursued academic excellence throughout his life.” He went on to say, “The KAIST-NYU Joint Campus, which will be completed on the foundation laid by President Emeritus Sexton, will serve as the focal point that will attract global talents flooding into New York by the driving force created from the synergy of the two universities as well as serving as a starting point for KAIST's outstanding talents to pursue their dreams toward the world.” KAIST signed a cooperation agreement with NYU in June of 2022 to build a joint campus, and held a presentation of signage for the KAIST-NYU Joint Campus in September. Currently, about 60 faculty members are planning to begin joint research initiatives in seven fields, including robotics, AI, brain sciences, and climate change. In addition, cooperation in the field of education, including student exchange, minors, double majors, and joint degrees, is under discussion.
2023.02.17
View 6577
A Quick but Clingy Creepy-Crawler that will MARVEL You
Engineered by KAIST Mechanics, a quadrupedal robot climbs steel walls and crawls across metal ceilings at the fastest speed that the world has ever seen. < Photo 1. (From left) KAIST ME Prof. Hae-Won Park, Ph.D. Student Yong Um, Ph.D. Student Seungwoo Hong > - Professor Hae-Won Park's team at the Department of Mechanical Engineering developed a quadrupedal robot that can move at a high speed on ferrous walls and ceilings. - It is expected to make a wide variety of contributions as it is to be used to conduct inspections and repairs of large steel structures such as ships, bridges, and transmission towers, offering an alternative to dangerous or risky activities required in hazardous environments while maintaining productivity and efficiency through automation and unmanning of such operations. - The study was published as the cover paper of the December issue of Science Robotics. KAIST (President Kwang Hyung Lee) announced on the 26th that a research team led by Professor Hae-Won Park of the Department of Mechanical Engineering developed a quadrupedal walking robot that can move at high speed on steel walls and ceilings named M.A.R.V.E.L. - rightly so as it is a Magnetically Adhesive Robot for Versatile and Expeditious Locomotion as described in their paper, “Agile and Versatile Climbing on Ferromagnetic Surfaces with a Quadrupedal Robot.” (DOI: 10.1126/scirobotics.add1017) To make this happen, Professor Park's research team developed a foot pad that can quickly turn the magnetic adhesive force on and off while retaining high adhesive force even on an uneven surface through the use of the Electro-Permanent Magnet (EPM), a device that can magnetize and demagnetize an electromagnet with little power, and the Magneto-Rheological Elastomer (MRE), an elastic material made by mixing a magnetic response factor, such as iron powder, with an elastic material, such as rubber, which they mounted on a small quadrupedal robot they made in-house, at their own laboratory. These walking robots are expected to be put into a wide variety of usage, including being programmed to perform inspections, repairs, and maintenance tasks on large structures made of steel, such as ships, bridges, transmission towers, large storage areas, and construction sites. This study, in which Seungwoo Hong and Yong Um of the Department of Mechanical Engineering participated as co-first authors, was published as the cover paper in the December issue of Science Robotics. < Image on the Cover of 2022 December issue of Science Robotics > Existing wall-climbing robots use wheels or endless tracks, so their mobility is limited on surfaces with steps or irregularities. On the other hand, walking robots for climbing can expect improved mobility in obstacle terrain, but have disadvantages in that they have significantly slower moving speeds or cannot perform various movements. In order to enable fast movement of the walking robot, the sole of the foot must have strong adhesion force and be able to control the adhesion to quickly switch from sticking to the surface or to be off of it. In addition, it is necessary to maintain the adhesion force even on a rough or uneven surface. To solve this problem, the research team used the EPM and MRE for the first time in designing the soles of walking robots. An EPM is a magnet that can turn on and off the electromagnetic force with a short current pulse. Unlike general electromagnets, it has the advantage that it does not require energy to maintain the magnetic force. The research team proposed a new EPM with a rectangular structure arrangement, enabling faster switching while significantly lowering the voltage required for switching compared to existing electromagnets. In addition, the research team was able to increase the frictional force without significantly reducing the magnetic force of the sole by covering the sole with an MRE. The proposed sole weighs only 169 g, but provides a vertical gripping force of about *535 Newtons (N) and a frictional force of 445 N, which is sufficient gripping force for a quadrupedal robot weighing 8 kg. * 535 N converted to kg is 54.5 kg, and 445 N is 45.4 kg. In other words, even if an external force of up to 54.5 kg in the vertical direction and up to 45.4 kg in the horizontal direction is applied (or even if a corresponding weight is hung), the sole of the foot does not come off the steel plate. MARVEL climbed up a vertical wall at high speed at a speed of 70 cm per second, and was able to walk while hanging upside down from the ceiling at a maximum speed of 50 cm per second. This is the world's fastest speed for a walking climbing robot. In addition, the research team demonstrated that the robot can climb at a speed of up to 35 cm even on a surface that is painted, dirty with dust and the rust-tainted surfaces of water tanks, proving the robot's performance in a real environment. It was experimentally demonstrated that the robot not only exhibited high speed, but also can switch from floor to wall and from wall to ceiling, and overcome 5-cm high obstacles protruding from walls without difficulty. The new climbing quadrupedal robot is expected to be widely used for inspection, repair, and maintenance of large steel structures such as ships, bridges, transmission towers, oil pipelines, large storage areas, and construction sites. As the works required in these places involves risks such as falls, suffocation and other accidents that may result in serious injuries or casualties, the need for automation is of utmost urgency. One of the first co-authors of the paper, a Ph.D. student, Yong Um of KAIST’s Department of Mechanical Engineering, said, "By the use of the magnetic soles made up of the EPM and MRE and the non-linear model predictive controller suitable for climbing, the robot can speedily move through a variety of ferromagnetic surfaces including walls and ceilings, not just level grounds. We believe this would become a cornerstone that will expand the mobility and the places of pedal-mobile robots can venture into." He added, “These robots can be put into good use in executing dangerous and difficult tasks on steel structures in places like the shipbuilding yards.” This research was carried out with support from the National Research Foundation of Korea's Basic Research in Science & Engineering Program for Mid-Career Researchers and Korea Shipbuilding & Offshore Engineering Co., Ltd.. < Figure 1. The quadrupedal robot (MARVEL) walking over various ferrous surfaces. (A) vertical wall (B) ceiling. (C) over obstacles on a vertical wall (D) making floor-to-wall and wall-to-ceiling transitions (E) moving over a storage tank (F) walking on a wall with a 2-kg weight and over a ceiling with a 3-kg load. > < Figure 2. Description of the magnetic foot (A) Components of the magnet sole: ankle, Square Eletro-Permanent Magnet(S-EPM), MRE footpad. (B) Components of the S-EPM and MRE footpad. (C) Working principle of the S-EPM. When the magnetization direction is aligned as shown in the left figure, magnetic flux comes out of the keeper and circulates through the steel plate, generating holding force (ON state). Conversely, if the magnetization direction is aligned as shown in the figure on the right, the magnetic flux circulates inside the S-EPM and the holding force disappears (OFF state). > Video Introduction: Agile and versatile climbing on ferromagnetic surfaces with a quadrupedal robot - YouTube
2022.12.30
View 12399
EE Professor Youjip Won Elected as the President of Korean Institute of Information Scientists and Engineers for 2024
< Professor Youjip Won of KAIST School of Electrical Engineering > Professor Youjip Won of KAIST School of Electrical Engineering was elected as the President of Korean Institute of Information Scientists and Engineers (KIISE) for the Succeding Term for 2023 on November 4th, 2022. Professor Won will serve as the 39th President of KIISE for one year starting from Jan. 1, 2024. He is one of the leading experts on Operating Systems, with a particular emphasis on storage systems. Korean Institute of Information Scientists and Engineers (KIISE), one of the most prestigious Korean academic institutions in the field of computer and software, was founded in 1973 and boasts a membership of over 42,000 people and 437 special/group members. KIISE is responsible for annually publishing 72 periodicals and holding 50 academic conferences.
2022.11.15
View 4015
NYC-KAIST Cooperation Agreement Signed in New York for KAIST NYU Joint Campus
A ceremony was held to celebrate the signing of the Cooperative Agreement between NYC and KAIST and the presentation of the signage for KAIST NYU Joint Campus at NYU’s Kimmel Center in Manhattan. KAIST President Kwang Hyung Lee (left) and NYU President Andrew Hamilton (right) KAIST (President Kwang Hyung Lee) signed a cooperative agreement with the City of New York and had an official showing of the signage for the Joint Campus of KAIST and New York University (NYU) on September 21 at 4:00 pm (Eastern Standard Time) at NYU’s Kimmel Center in New York City with the NYC Mayor Eric Adams, the Korean Minister of Science and ICT Dr. Lee Jong-ho, NYU Chairman William Berkley, NYU President Andrew Hamilton, and other distinguished guests in attendance. KAIST and NYU signed a Memorandum of Understanding in June about building a joint campus in an effort to educate global talent. As a follow-up measure, NYU has provided KAIST with space to begin joint research programs and held a ceremony to present the signage designed for the future KAIST NYU Campus. In line with these efforts, KAIST has also signed an agreement with New York City, the administrative authority in charge of the establishment of the campus, for mutual cooperation. NYU is a prestigious university headquartered in Manhattan, New York. It has nurtured outstanding talents in the humanities, art, and basic sciences, including 38 Nobel Prize winners, 5 Fields Prize winners, 26 Pulitzer Prize winners, and 38 Academy Award winners to be deserving of the evaluation. The proposed joint campus is to be centered on science, technology, engineering, and mathematics (STEM) by combining NYU's excellent basic sciences and convergence research capabilities with KAIST's globally renowned science and technology capabilities. The joint initiative is expected to launch in 2023; its programs will focus on areas such as AI Basic Science, AI Convergence Brain Science, AI-Applied Cyber Security, Cyber Security, and Sustainable High-Tech Smart City/Climate Change in order to lead the Digital Era and to solve the problems that surfaced following the COVID-19 pandemic. In addition, in order to prepare for the Post-AI Era, it was decided to create the “New Engineering” program for undergraduate program that employs a hyper-convergence learning model that combines project-based, problem-solving learning (PBL, PSL) pedagogy. ▲ Biomedical Engineering- Research and development of technology to respond to the entire cycle (prevention-treatment-diagnosis-prediction) for a new infectious disease (Disease X) by converging new technologies such as IT and NT with biomedical technologies ▲ AI Convergence Neuroscience- Research on brain-machine interaction and brain-based machine learning through AI technology convergence ▲ AI Science- Algorithm development and in-depth research in preparation for the post AI era ▲ Sustainability and Climate Change- R&DB for advanced smart cities, sustainability for the global environment and carbon zero ▲ Next-generation Wireless Communications- From ICT to AIT: Research on 6G/7G related technologies, new communications theories, and etc. ▲ Cyber Security- Advanced research on protection of digital information and information safety/reliability KAIST President Kwang Hyung Lee (left) and NYC Mayor Eric Adams (right) The KAIST NYU Joint Campus has started enlisting professors and researchers from both institutions to participate in the collaboration. The campus will also function as the headquarter that will oversee the operation of the joint research program. At Daejeon, KAIST is also setting up a location for NYU on its main campus to provide space for NYU researchers upon their visit to KAIST. The KAIST NYU Joint Campus, which has begun to take basic shape with the space for collaboration rendered this time, is to be upgraded to “KAIST New York Campus” in the future to function also as an industry-academic cooperation campus in which that promotes strategic cooperation with industries and expands start-up opportunities. To this end, the related procedures from the detailing of the establishment plans through a preliminary feasibility studies, to deliberation and decision on whether to proceed with the establishment by the KAIST Board of Trustees, will be taken. The KAIST NYU Campus is expected to serve as a stepping stone for the outstanding talents of KAIST to pursue their dreams in the global market and research environment while seizing the attention of the world-class talents drawn to New York at the same time. In addition, by combining NYU's strong basic academic capabilities with KAIST’s strengths, it is expected to contribute to achieving 'global innovation' by creating synergies in various fields such as education, research, and entrepreneurship. The future KAIST-NYU Campus is also expected to encompass an industry-academic cooperation campus with industrial partners and startups. Meanwhile, KAIST is planning to expand its excellent scientific and technological capabilities to the global stage through the cooperative agreement with New York City, and to prepare a pathway for KAIST students, faculty, and startups to enter their respective fields in the global markets. In the future, KAIST plans to explore areas of cooperation in different fields, such as education, economy, society, and culture, to prepare and implement detailed cooperation plans. < KAIST-New York City Cooperation Items (Example) > ▲ Education: Joint degree program with a university in New York City, training of key talents in the field of artificial intelligence, etc. ▲ Economy: A hub for technology startups, job creation in the tech sector, etc. ▲ Society: Economics, finance, media-related engineering research, etc. ▲ Culture: Diversity-based culture and art-tech research, etc.▲ Etc: Joint research in the field of artificial intelligence healthcare, etc. As a global mecca for startups, education, and investment, New York has a well-developed global network for cultural diversity and successful career development, and has great power to attract various resources including funds and talented individuals. Based on this, it has established itself as a mecca of global tech companies and global top media groups, and is building the reputation as 'Silicon Alley' in addition to its legends of the ‘Wall Street'. Dr. Andrew Hamilton, the president of NYU, said, “We’re delighted by our newly established partnership with KAIST. We see great potential in the opportunities to collaborate on development of courses, research, cutting edge technologies, university-level courses, degrees, entrepreneurship initiatives and industrial partnerships, and exchanges. We believe this partnership is very much in line with NYU’s commitment to global engagement and will make important contributions to New York’s tech sector. It’s exciting to think how much NYU and KAIST have much to learn from one another, and how much we may accomplish together.” New York City Mayor Eric Adams said, “We’re proud to have helped facilitate this partnership between KAIST and New York University, which will be a real win for students and help drive continued innovation in our city.” He added, “From the time that senior members of our administration learned about this opportunity during a recent trip to South Korea, we have worked closely with KAIST to develop strategies for increasing their presence and investments in New York. This is the start of a relationship that I am confident will bring even more academic, business, and technological opportunities to the five boroughs.” Dr. Kwang Hyung Lee, the president of KAIST, urged, “Based on the KAIST-NYU partnership, we must create an interdisciplinary hyper-convergence model of collaboration and use cutting-edge tools to create an innovative model for new type of problem-solving engineering education to prepare to solve the challenges facing the world.” He went on to stress, “The new fusion engineering degree program will leverage the unique strengths of the two institutions to provide a uniquely colored education not found anywhere else.” In addition, he added, “KAIST will utilize the advantages that are unique to the global city of New York to contribute to advancing the science and technology research in New York City and creating jobs in the tech sector to lead the renaissance of Silicon Alley.”
2022.09.27
View 10426
Phage resistant Escherichia coli strains developed to reduce fermentation failure
A genome engineering-based systematic strategy for developing phage resistant Escherichia coli strains has been successfully developed through the collaborative efforts of a team led by Professor Sang Yup Lee, Professor Shi Chen, and Professor Lianrong Wang. This study by Xuan Zou et al. was published in Nature Communications in August 2022 and featured in Nature Communications Editors’ Highlights. The collaboration by the School of Pharmaceutical Sciences at Wuhan University, the First Affiliated Hospital of Shenzhen University, and the KAIST Department of Chemical and Biomolecular Engineering has made an important advance in the metabolic engineering and fermentation industry as it solves a big problem of phage infection causing fermentation failure. Systems metabolic engineering is a highly interdisciplinary field that has made the development of microbial cell factories to produce various bioproducts including chemicals, fuels, and materials possible in a sustainable and environmentally friendly way, mitigating the impact of worldwide resource depletion and climate change. Escherichia coli is one of the most important chassis microbial strains, given its wide applications in the bio-based production of a diverse range of chemicals and materials. With the development of tools and strategies for systems metabolic engineering using E. coli, a highly optimized and well-characterized cell factory will play a crucial role in converting cheap and readily available raw materials into products of great economic and industrial value. However, the consistent problem of phage contamination in fermentation imposes a devastating impact on host cells and threatens the productivity of bacterial bioprocesses in biotechnology facilities, which can lead to widespread fermentation failure and immeasurable economic loss. Host-controlled defense systems can be developed into effective genetic engineering solutions to address bacteriophage contamination in industrial-scale fermentation; however, most of the resistance mechanisms only narrowly restrict phages and their effect on phage contamination will be limited. There have been attempts to develop diverse abilities/systems for environmental adaptation or antiviral defense. The team’s collaborative efforts developed a new type II single-stranded DNA phosphorothioation (Ssp) defense system derived from E. coli 3234/A, which can be used in multiple industrial E. coli strains (e.g., E. coli K-12, B and W) to provide broad protection against various types of dsDNA coliphages. Furthermore, they developed a systematic genome engineering strategy involving the simultaneous genomic integration of the Ssp defense module and mutations in components that are essential to the phage life cycle. This strategy can be used to transform E. coli hosts that are highly susceptible to phage attack into strains with powerful restriction effects on the tested bacteriophages. This endows hosts with strong resistance against a wide spectrum of phage infections without affecting bacterial growth and normal physiological function. More importantly, the resulting engineered phage-resistant strains maintained the capabilities of producing the desired chemicals and recombinant proteins even under high levels of phage cocktail challenge, which provides crucial protection against phage attacks. This is a major step forward, as it provides a systematic solution for engineering phage-resistant bacterial strains, especially industrial bioproduction strains, to protect cells from a wide range of bacteriophages. Considering the functionality of this engineering strategy with diverse E. coli strains, the strategy reported in this study can be widely extended to other bacterial species and industrial applications, which will be of great interest to researchers in academia and industry alike. Fig. A schematic model of the systematic strategy for engineering phage-sensitive industrial E. coli strains into strains with broad antiphage activities. Through the simultaneous genomic integration of a DNA phosphorothioation-based Ssp defense module and mutations of components essential for the phage life cycle, the engineered E. coli strains show strong resistance against diverse phages tested and maintain the capabilities of producing example recombinant proteins, even under high levels of phage cocktail challenge.
2022.08.23
View 8969
KAIST Research Team Proves How a Neurotransmitter may be the Key in Controlling Alzheimer’s Toxicity
With nearly 50 million dementia patients worldwide, and Alzheimers’s disease is the most common neurodegenerative disease. Its main symptom is the impairment of general cognitive abilities, including the ability to speak or to remember. The importance of finding a cure is widely understood with increasingly aging population and the life expectancy being ever-extended. However, even the cause of the grim disease is yet to be given a clear definition. A KAIST research team in the Department of Chemistry led by professor Mi Hee Lim took on a lead to discovered a new role for somatostatin, a protein-based neurotransmitter, in reducing the toxicity caused in the pathogenic mechanism taken towards development of Alzheimer’s disease. The study was published in the July issue of Nature Chemistry under the title, “Conformational and functional changes of the native neuropeptide somatostatin occur in the presence of copper and amyloid-β”. According to the amyloid hypothesis, the abnormal deposition of Aβ proteins causes death of neuronal cells. While Aβ agglomerations make up most of the aged plaques through fibrosis, in recent studies, high concentrations of transitional metal were found in the plaques from Alzheimer’s patients. This suggests a close interaction between metallic ions and Aβ, which accelerates the fibrosis of proteins. Copper in particular is a redox-activating transition metal that can produce large amounts of oxygen and cause serious oxidative stress on cell organelles. Aβ proteins and transition metals can closely interact with neurotransmitters at synapses, but the direct effects of such abnormalities on the structure and function of neurotransmitters are yet to be understood. Figure 1. Functional shift of somatostatin (SST) by factors in the pathogenesis of Alzheimer's disease. Figure 2. Somatostatin’s loss-of-function as neurotransmitter. a. Schematic diagram of SST auto-aggregation due to Alzheimer's pathological factors. b. SST’s aggregation by copper ions. c. Coordination-prediction structure and N-terminal folding of copper-SST. d. Inhibition of SST receptor binding specificity by metals. In their research, Professor Lim’s team discovered that when somatostatin, the protein-based neurotransmitter, is met with copper, Aβ, and metal-Aβ complexes, self-aggregates and ceases to perform its innate function of transmitting neural signals, but begins to attenuate the toxicity and agglomeration of metal-Aβ complexes. Figure 3. Gain-of-function of somatostatin (SST) in the dementia setting. a. Prediction of docking of SST and amyloid beta. b. SST making metal-amyloid beta aggregates into an amorphous form. c. Cytotoxic mitigation effect of SST. d. SST mitigating the interaction between amyloid beta protein with the cell membrane. This research, by Dr. Jiyeon Han et al. from the KAIST Department of Chemistry, revealed the coordination structure between copper and somatostatin at a molecular level through which it suggested the agglomeration mechanism, and discovered the effects of somatostatin on Aβ agglomeration path depending on the presence or absence of metals. The team has further confirmed somatostatin’s receptor binding, interactions with cell membranes, and effects on cell toxicity for the first time to receive international attention. Professor Mi Hee Lim said, “This research has great significance in having discovered a new role of neurotransmitters in the pathogenesis of Alzheimer’s disease.” “We expect this research to contribute to defining the pathogenic network of neurodegenerative diseases caused by aging, and to the development of future biomarkers and medicine,” she added. This research was conducted jointly by Professor Seung-Hee Lee’s team of KAIST Department of Biological Sciences, Professor Kiyoung Park’s Team of KAIST Department of Chemistry, and Professor Yulong Li’s team of Peking University. The research was funded by Basic Science Research Program of the National Research Foundation of Korea and KAIST. For more information about the research team, visit the website: https://sites.google.com/site/miheelimlab/1-professor-mi-hee-lim.
2022.07.29
View 10335
KAIST Partners with Korea National Sport University
KAIST President Kwang Hyung Lee signed an MOU with Korea National Sport University (KNSU) President Yong-Kyu Ahn for collaboration in education and research in the fields of sports science and technology on April 5 at the KAIST main campus. The agreement also extends to student and credit exchanges between the two universities. With this signing, KAIST plans to develop programs in which KAIST students can participate in the diverse sports classes and activities offered at KNSU. Officials from KNSU said that this collaboration with KAIST will provide a new opportunity to recognize the importance of sports science more extensively. They added that KNSU will continue to foster more competitive sports talents who understand the convergence between sports science and technology. The two universities also plan to conduct research on body mechanics optimizing athletes’ best performance, analyze how the muscles of different events’ athletes move, and will propose creative new solutions utilizing robot rehabilitation and AR technologies. It is expected that the research will extend to the physical performance betterment of the general public, especially for aged groups and the development of training solutions for musculoskeletal injury prevention as Korean society deals with its growing aging population. President Lee said, “I look forward to the synergic impact when KAIST works together with the nation’s top sports university. We will make every effort to spearhead the wellbeing of the general public in our aging society as well as for growth of sports.” President Ahn said, “The close collaboration between KAIST and KNSU will revitalize the sports community that has been staggering due to the Covid-19 pandemic and will contribute to the advancement of sports science in Korea.”
2022.04.07
View 4011
Scientist Discover How Circadian Rhythm Can Be Both Strong and Flexible
Study reveals that master and slave oscillators function via different molecular mechanisms From tiny fruit flies to human beings, all animals on Earth maintain their daily rhythms based on their internal circadian clock. The circadian clock enables organisms to undergo rhythmic changes in behavior and physiology based on a 24-hour circadian cycle. For example, our own biological clock tells our brain to release melatonin, a sleep-inducing hormone, at night time. The discovery of the molecular mechanism of the circadian clock was bestowed the Nobel Prize in Physiology or Medicine 2017. From what we know, no one centralized clock is responsible for our circadian cycles. Instead, it operates in a hierarchical network where there are “master pacemaker” and “slave oscillator”. The master pacemaker receives various input signals from the environment such as light. The master then drives the slave oscillator that regulates various outputs such as sleep, feeding, and metabolism. Despite the different roles of the pacemaker neurons, they are known to share common molecular mechanisms that are well conserved in all lifeforms. For example, interlocked systems of multiple transcriptional-translational feedback loops (TTFLs) composed of core clock proteins have been deeply studied in fruit flies. However, there is still much that we need to learn about our own biological clock. The hierarchically-organized nature of master and slave clock neurons leads to a prevailing belief that they share an identical molecular clockwork. At the same time, the different roles they serve in regulating bodily rhythms also raise the question of whether they might function under different molecular clockworks. Research team led by Professor Kim Jae Kyoung from the Department of Mathematical Sciences, a chief investigator at the Biomedical Mathematics Group at the Institute for Basic Science, used a combination of mathematical and experimental approaches using fruit flies to answer this question. The team found that the master clock and the slave clock operate via different molecular mechanisms. In both master and slave neurons of fruit flies, a circadian rhythm-related protein called PER is produced and degraded at different rates depending on the time of the day. Previously, the team found that the master clock neuron (sLNvs) and the slave clock neuron (DN1ps) have different profiles of PER in wild-type and Clk-Δ mutant Drosophila. This hinted that there might be a potential difference in molecular clockworks between the master and slave clock neurons. However, due to the complexity of the molecular clockwork, it was challenging to identify the source of such differences. Thus, the team developed a mathematical model describing the molecular clockworks of the master and slave clocks. Then, all possible molecular differences between the master and slave clock neurons were systematically investigated by using computer simulations. The model predicted that PER is more efficiently produced and then rapidly degraded in the master clock compared to the slave clock neurons. This prediction was then confirmed by the follow-up experiments using animal. Then, why do the master clock neurons have such different molecular properties from the slave clock neurons? To answer this question, the research team again used the combination of mathematical model simulation and experiments. It was found that the faster rate of synthesis of PER in the master clock neurons allows them to generate synchronized rhythms with a high level of amplitude. Generation of such a strong rhythm with high amplitude is critical to delivering clear signals to slave clock neurons. However, such strong rhythms would typically be unfavorable when it comes to adapting to environmental changes. These include natural causes such as different daylight hours across summer and winter seasons, up to more extreme artificial cases such as jet lag that occurs after international travel. Thanks to the distinct property of the master clock neurons, it is able to undergo phase dispersion when the standard light-dark cycle is disrupted, drastically reducing the level of PER. The master clock neurons can then easily adapt to the new diurnal cycle. Our master pacemaker’s plasticity explains how we can quickly adjust to the new time zones after international flights after just a brief period of jet lag. It is hoped that the findings of this study can have future clinical implications when it comes to treating various disorders that affect our circadian rhythm. Professor Kim notes, “When the circadian clock loses its robustness and flexibility, the circadian rhythms sleep disorders can occur. As this study identifies the molecular mechanism that generates robustness and flexibility of the circadian clock, it can facilitate the identification of the cause of and treatment strategy for the circadian rhythm sleep disorders.” This work was supported by the Human Frontier Science Program. -PublicationEui Min Jeong, Miri Kwon, Eunjoo Cho, Sang Hyuk Lee, Hyun Kim, Eun Young Kim, and Jae Kyoung Kim, “Systematic modeling-driven experiments identify distinct molecularclockworks underlying hierarchically organized pacemaker neurons,” February 22, 2022, Proceedings of the National Academy of Sciences of the United States of America -ProfileProfessor Jae Kyoung KimDepartment of Mathematical SciencesKAIST
2022.02.23
View 7084
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