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Two Alumni Win the Korea Best Scientist and Technologist Awards
Vice Chairman Ki-Nam Kim (Left) and Distinguished Professor Sukbok Chang (Right)
<ⓒ Photo by MSIT and KOFST>
Distinguished KAIST Professor Sukbok Chang from the Department of Chemistry and Vice Chairman Ki-Nam Kim of Samsung Electronics were selected as the winners of the “2019 Korea Best Scientist and Technologist Awards” by the Ministry of Science and ICT (MSIT) and the Korean Federation of Science and Technology Societies (KOFST). The awards, which were first handed out in 2003, are the highest honor bestowed to the two most outstanding scientists in Korea every year, and this year’s awardees are of greater significance as they are both KAIST alumni.
Professor Chang was recognized for his pioneering achievements and lifetime contributions to the development of carbon-hydrogen activation strategies, especially for carbon-carbon, carbon-nitrogen, and carbon-oxygen formations. His research group has also been actively involved in the development of highly selective catalytic systems allowing the controlled defunctionalization of bio-derived platform substrates under mild conditions, and opening a new avenue for the utilization of biomass-derived platform chemicals. The results of his study have been introduced worldwide through many prestigious journals including Science, Nature Chemistry, and Nature Catalysis, making him one of the world's top 1% researchers by the number of references made to his papers by his peers over four consecutive years from 2015 to 2018.
Vice Chairman Kim, who received his M.E. degree from KAIST’s School of Electrical Engineering in 1983, has been credited with playing a leading role in the development of system semiconductors.
The awards were conferred on July 4 at the opening ceremony of the 2019 Korea Science and Technology Annual Meeting.
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2019.07.09 View 9703 -
Hydrogen-Natural Gas Hydrates Harvested by Natural Gas
A hydrogen-natural gas blend (HNGB) can be a game changer only if it can be stored safely and used as a sustainable clean energy resource. A recent study has suggested a new strategy for stably storing hydrogen, using natural gas as a stabilizer. The research proposed a practical gas phase modulator based synthesis of HNGB without generating chemical waste after dissociation for the immediate service.
The research team of Professor Jae Woo Lee from the Department of Chemical and Biomolecular Engineering in collaboration with the Gwangju Institute of Science and Technology (GIST) demonstrated that the natural gas modulator based synthesis leads to significantly reduced synthesis pressure simultaneously with the formation of hydrogen clusters in the confined nanoporous cages of clathrate hydrates. This approach minimizes the environmental impact and reduces operation costs since clathrate hydrates do not generate any chemical waste in both the synthesis and decomposition processes.
For the efficient storage and transportation of hydrogen, numerous materials have been investigated. Among others, clathrate hydrates offer distinct benefits. Clathrate hydrates are nanoporous inclusion compounds composed of a 3D network of polyhedral cages made of hydrogen-bonded ‘host’ water molecules and captured ‘guest’ gas or liquid molecules.
In this study, the research team used two gases, methane and ethane, which have lower equilibrium conditions compared to hydrogen as thermodynamic stabilizers. As a result, they succeeded in stably storing the hydrogen-natural gas compound in hydrates. According to the composition ratio of methane and ethane, structure I or II hydrates can be formed, both of which can stably store hydrogen-natural gas in low-pressure conditions.
The research team found that two hydrogen molecules are stored in small cages in tuned structure I hydrates, while up to three hydrogen molecules can be stored in both small and large cages in tuned structure II hydrates. Hydrates can store gas up to about 170-times its volume and the natural gas used as thermodynamic stabilizers in this study can also be used as an energy source.
The research team developed technology to produce hydrates from ice, produced hydrogen-natural gas hydrates by substitution, and successfully observed that the tuning phenomenon only occurs when hydrogen is involved in hydrate formation from the start for both structures of hydrates.
They expect that the findings can be applied to not only an energy-efficient gas storage material, but also a smart platform to utilize hydrogen natural gas blends, which can serve as a new alternative energy source with targeted hydrogen contents by designing synthetic pathways of mixed gas hydrates.
The research was published online in Energy Storage Materials on June 6, with the title ‘One-step formation of hydrogen clusters in clathrate hydrates stabilized via natural gas blending’.
Professor Lee said, “HNGB will utilize the existing natural gas infrastructure for transportation, so it is very likely that we can commercialize this hydrate system. We are investigating the kinetic performance through a follow-up strategy to increase the volume of gas storage.
This study was funded by the National Research Foundation of Korea and BK21 plus program.
(Figure1. Schematics showing the storage method for hydrogen in a natural gas hydrate using a substitution method and storage method directly from ice to a hydrogen-natural gas hydrate.)
(Figure 2. Artificially synthesized and dissociated hydrogen-natural gas hydrates. The Raman spectra of tuned sI and sII hydrate showing the hydrogen clusters in each cage.)
2019.06.21 View 39766 -
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 View 42321 -
KAIST Researchers Receive Awards at the 13th Asian Congress on Biotechnology
(From left: Seon Young Park, Dr. So Young Choi, and Yoojin Choi)
Researchers in the laboratory of KAIST Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering swept awards at the 13th Asian Congress on Biotechnology held in Thailand last month. The conference awarded a total of eight prizes in the areas of best research and best poster presentation. This is an exceptional case in which members of one research team received almost half of the awards at an international conference.
Dr. So Young Choi received the Best Research Award, while Ph.D. candidates Yoojin Choi and Seon Young Park each received the Best Poster Presentation Award at the conference held in Khon Kaen, Thailand from July 23 to 27.
The Asian Congress on Biotechnology is an international conference in which scientists and industry experts in Asia and from around the world gather to present recent research findings in the field of biotechnology. At the conference, around 400 researchers in biotechnology from 25 countries, including Korea, gathered to present and discuss various research findings under the theme of “Bioinnovation and Bioeconomy.”
Distinguished Professor Sang Yup Lee attended the conference to give the opening plenary lecture on the topic of ‘Systems Strategies in Biotechnology.’ Professor Lee announced, “I have attended international conferences with students for the last 20 years, but this is the first in which my team received three awards at an international conference that only honors a total of eight awards, three for Best Research and five for Best Presentation.”
Dr. Choi presented research results on poly (lactate-co-glycolate) (PLGA) synthesis through a biological method using micro-organisms and received the Best Research Award. PLGA is a random copolymer of DL-lactic and glycolic acids and is a biopolymer widely used for biomedical applications. PLGA is biodegradable, biocompatible, and nontoxic, and thus has been approved by the US Food and Drug Administration (FDA) for its use in implants, drug delivery, and sutures.
Dr. Choi’s research was deemed to be innovative for synthesizing PLGA from glucose and xylose in cells through metabolic engineering of E.Coli. Dr. Choi received her Ph.D. under the supervision of Distinguished Professor Lee this February and is currently conducting post-doc research.
Ph.D. candidate Choi presented her research on the use of recombinant E.Coli for the biological synthesis of various nanoparticles and received the Best Poster Presentation award. Choi used recombinant E.Coli-expressing proteins and peptides that adsorb to heavy metals to biologically synthesize diverse metal nanoparticles such as single-nanoparticle including gold and silver, quantum dots, and magnetic nanoparticles for the first time. The synthesized nanoparticles can be used in the fields of bio-imaging, diagnosis, environment, and energy.
Ph.D. candidate Park, who also received the Best Poster Presentation award, synthesized and increased production of astanxanthin, a strong antioxidant found in nature, in E.Coli using metabolic engineering. Astanxanthin is a carotenoid pigment found in salmon and shrimp that widely used in health products and cosmetics.
2017.08.01 View 12754 -
A Transport Technology for Nanowires Thermally Treated at 700 Celsius Degrees
Professor Jun-Bo Yoon and his research team of the Department of Electrical Engineering at KAIST developed a technology for transporting thermally treated nanowires to a flexible substrate and created a high performance device for collecting flexible energy by using the new technology.
Mr. Min-Ho Seo, a Ph.D. candidate, participated in this study as the first author. The results were published online on January 30th in ACS Nano, an international journal in the field of nanoscience and engineering. (“Versatile Transfer of an Ultralong and Seamless Nanowire Array Crystallized at High Temperature for Use in High-performance Flexible Devices,” DOI: 10.1021/acsnano.6b06842)
Nanowires are one of the most representative nanomaterials. They have wire structures with dimensions in nanometers. The nanowires are widely used in the scientific and engineering fields due to their prominent physical and chemical properties that depend on a one-dimensional structure, and their high applicability.
Nanowires have much higher performance if their structure has unique features such as an excellent arrangement and a longer-than-average length. Many researchers are thus actively participating in the research for making nanowires without much difficulty, analyzing them, and developing them for high performance application devices.
Scientists have recently favored a research topic on making nanowires chemically and physically on a flexible substrate and applies the nanowires to a flexible electric device such as a high performance wearable sensor.
The existing technology, however, mixed nanowires from a chemical synthesis with a solution and spread the mixture on a flexible substrate. The resultant distribution was random, and it was difficult to produce a high performance device based on the structural advantages of nanowires. In addition, the technology used a cutting edge nano-process and flexible materials, but this was not economically beneficial. The production of stable materials at a temperature of 700 Celsius degrees or higher is unattainable, a great challenge for the application.
To solve this problem, the research team developed a new nano-transfer technology that combines a silicon nano-grating board with a large surface area and a nano-sacrificial layer process. A nano-sacrificial layer exists between nanowires and a nano-grating board, which acts as the mold for the nano-transfer. The new technology allows the device undergo thermal treatment. After this, the layer disappears when the nanowires are transported to a flexible substrate.
This technology also permits the stable production of nanowires with secured properties at an extremely high temperature. In this case, the nanowires are neatly organized on a flexible substrate. The research team used the technology to manufacture barium carbonate nanowires on top of the flexible substrate. The wires secured their properties at a temperature of 700℃ or above. The team employed the collection of wearable energy to obtain much higher electrical energy than that of an energy collecting device designed based on regular barium titanate nanowires.
The researchers said that their technology is built upon a semiconductor process, known as Physical Vapor Deposition that allows various materials such as ceramics and semiconductors to be used for flexible substrates of nanowires. They expected that high performance flexible electric devices such as flexible transistors and thermoelectric elements can be produced with this method.
Mr. Seo said, “In this study, we transported nanowire materials with developed properties on a flexible substrate and showed an increase in device performance. Our technology will be fundamental to the production of various nanowires on a flexible substrate as well as the feasibility of making high performance wearable electric devices.”
This research was supported by the Leap Research Support Program of the National Research Foundation of Korea.
Fig. 1. Transcription process of new, developed nanowires (a) and a fundamental mimetic diagram of a nano-sacrificial layer (b)
Fig. 2. Transcription results from using gold (AU) nanowires. The categories of the results were (a) optical images, (b) physical signals, (c) cross-sectional images from a scanning electron microscope (SEM), and (d-f) an electric verification of whether the perfectly arranged nanowires were made on a large surface.
Fig. 3. Transcription from using barium titanate (BaTiO3) nanowires. The results were (a) optical images, (b-e) top images taken from an SEM in various locations, and (f, g) property analysis.
Fig. 4. Mimetic diagram of the energy collecting device from using a BaTiO3 nanowire substrate and an optical image of the experiment for the miniature energy collecting device attached to an index finger.
2017.03.22 View 8366 -
Continuous Roll-Process Technology for Transferring and Packaging Flexible Large-Scale Integrated Circuits
A research team led by Professor Keon Jae Lee from KAIST and by Dr. Jae-Hyun Kim from the Korea Institute of Machinery and Materials (KIMM) has jointly developed a continuous roll-processing technology that transfers and packages flexible large-scale integrated circuits (LSI), the key element in constructing the computer’s brain such as CPU, on plastics to realize flexible electronics.
Professor Lee previously demonstrated the silicon-based flexible LSIs using 0.18 CMOS (complementary metal-oxide semiconductor) process in 2013 (ACS Nano, “In Vivo Silicon-based Flexible Radio Frequency Integrated Circuits Monolithically Encapsulated with Biocompatible Liquid Crystal Polymers”) and presented the work in an invited talk of 2015 International Electron Device Meeting (IEDM), the world’s premier semiconductor forum.
Highly productive roll-processing is considered a core technology for accelerating the commercialization of wearable computers using flexible LSI. However, realizing it has been a difficult challenge not only from the roll-based manufacturing perspective but also for creating roll-based packaging for the interconnection of flexible LSI with flexible displays, batteries, and other peripheral devices.
To overcome these challenges, the research team started fabricating NAND flash memories on a silicon wafer using conventional semiconductor processes, and then removed a sacrificial wafer leaving a top hundreds-nanometer-thick circuit layer. Next, they simultaneously transferred and interconnected the ultrathin device on a flexible substrate through the continuous roll-packaging technology using anisotropic conductive film (ACF). The final silicon-based flexible NAND memory successfully demonstrated stable memory operations and interconnections even under severe bending conditions. This roll-based flexible LSI technology can be potentially utilized to produce flexible application processors (AP), high-density memories, and high-speed communication devices for mass manufacture.
Professor Lee said, “Highly productive roll-process was successfully applied to flexible LSIs to continuously transfer and interconnect them onto plastics. For example, we have confirmed the reliable operation of our flexible NAND memory at the circuit level by programming and reading letters in ASCII codes. Out results may open up new opportunities to integrate silicon-based flexible LSIs on plastics with the ACF packing for roll-based manufacturing.”
Dr. Kim added, “We employed the roll-to-plate ACF packaging, which showed outstanding bonding capability for continuous roll-based transfer and excellent flexibility of interconnecting core and peripheral devices. This can be a key process to the new era of flexible computers combining the already developed flexible displays and batteries.”
The team’s results will be published on the front cover of Advanced Materials (August 31, 2016) in an article entitled “Simultaneous Roll Transfer and Interconnection of Silicon NAND Flash Memory.” (DOI: 10.1002/adma.201602339)
YouTube Link: https://www.youtube.com/watch?v=8OJjAEm27sw
Picture 1: This schematic image shows the flexible silicon NAND flash memory produced by the simultaneous roll-transfer and interconnection process.
Picture 2: The flexible silicon NAND flash memory is attached to a 7 mm diameter glass rod.
2016.09.01 View 10140 -
GSIS Graduates Its First Doctor
The Graduate School of Information Security at KAIST (GSIS) granted its first doctoral degree to Il-Goo Lee at the university’s 2016 commencement on February 19, 2016.
Lee received the degree for his dissertation entitled “Interference-Aware Secure Communications for Wireless LANs.”
He explained the background of his research:
“As we use wireless technology more and more in areas of the Internet of Things (IoT), unmanned vehicles, and drones, information security will become an issue of major concern. I would like to contribute to the advancement of communications technology to help minimize wireless interference between devices while ensuring their optimal performance.”
Based on his research, he developed a communications technique to increase wireless devices’ energy efficiency and the level of their security, and created a prototype to showcase that technique.
He plans to continue his research in the development of the next generation WiFi chip sets to protect the information security of IoT and wireless devices.
Since its establishment in March 2011, KAIST’s GSIS has conferred 50 master’s and one doctoral degrees.
2016.02.18 View 7645 -
Public Forum on the Development of High-Performance Supercomputing System
KAIST hosted a public forum on the development of high-performance supercomputing systems at the K Hotel in Seoul on December 17, 2015.
About 100 participants attended the forum, including Steve Kang, the President of KAIST; Jae-Moon Park, the Director General of Science, ICT and Future Planning of the Republic of Korea; Sun-Hwa Hahn, the President of the Korea Institute of Science and Technology Information; Sang-Gyu Park, the Director of the Electronics and Telecommunications Research Institute; Soon-Chill Lee, the Dean of KAIST’s Natural Sciences College; Jangwoo Kim, the Professor of Computer Science and Engineering of Pohang University of Science and Technology; and Kyung-Hak Suh, the Director of Convergence Technology Division at the National Research Foundation of Korea.
Also attending the forum were representatives from the private sector, including Sung-Soon Park, the President of Gluesys; Myung-Chul Lee, the Director of IMB Korea; Jin-Hyun Choi, the President of Cray Korea; and Chung-Gun Yoo, the Director of HP Korea.
KAIST created the High-performance Computing Development Forum in July this year. Since then, the forum has held four conferences and workshops to discuss issues related to the growth of supercomputing power in Korea.
This public forum consisted of a keynote speech on the “Policy Proposal for the Development of Supercomputers” by Professor Hyuk-Jae Lee of the Electrical and Computer Engineering Department at Seoul National University and panel discussions presided over by President Kang on the topic of “Development and Implementation Strategies to Build Korean Supercomputers.”
President Kang said, “I hope this public forum can serve as a place for designing the future of Korean supercomputers, and what we have discussed at the forum will be duly delivered to the government to help them develop policies necessary to build the computers.”
2015.12.16 View 6445 -
Public Lectures by KAIST's Humanities and Social Sciences Research Center
The Humanities and Social Sciences Research Center at KAIST offers public lectures at the International Seminar Hall of the Humanities and Social Sciences building on campus from November 12, 2015 to December 10, 2015. There will be four lectures, all of which will be available in Korean only.
The theme of the lectures is “social issues and strategic solutions.” Experts in various fields including women’s studies, criminal psychology, Go (a Chinese board game) and its philosophy, and Korean studies will participate, offering multifaceted analysis and solutions for social issues in Korea.
Joo-Hee Kim, a researcher at the Korean Women’s Institute of Ewha Women’s University, will lecture on “Problems of Loan Products Exclusively for Women” and discuss the background of "micro-loans" which are often targeted at women, while evaluating the logic of financial corporations behind marketing such products.
Lectures by Professor Ji-Sun Park from the Department of Social Psychology at Ewha Women’s University on “Understanding of Criminal Psychology from Letters,” Professor Soo-Hyun Jeong from the Department of Go at Myeongji University on “Life Lessons and Strategies from Playing Go,” and Professor Seung-Taek Ahn from Kyujanggak Institute for Korean Studies of Seoul National University on “Community Problems in Folk Culture” will follow.
The organizer of the lectures, Professor Jung-Hoon Kim of the Department of Humanities and Social Sciences at KAIST said,
“These lectures will provide local citizens and the KAIST family a wonderful opportunity to understand important social issues from the perspective of social science. It will also serve as a valuable time to think about how our social conflicts could differ from those of other countries, helping us to find solutions.”
To register for these free lectures, go to http://hss.kaist.ac.kr by November 9, 2015.
2015.11.06 View 6195 -
KAIST Invites Entrepreneurs and Experts to Participate in a Social Technology Innovation Symposium
The Research Institute for Social Technology and Innovation (RISTI) at KAIST hosted the Social Technology Innovation Symposium on November 4, 2015 in KI building, to which 100 social business entrepreneurs and experts in the field were invited.
Social businesses refer to activities of companies, which strive to resolve social problems such as environmental issues, income inequality, and aging societies while seeking profit at the same time. This is different from companies taking social responsibility and non-profit organization serving the community in that they attempt to solve social problems through a sustainable business model.
Held under the theme of “technology capabilities of companies and social business strategies,” this symposium was the first to gather representatives from social venture companies, medium-sized enterprises, and major companies at one place to share their experiences in a social business and to discuss future tasks.
The symposium was divided into sessions with three different topics ranging from social business strategies using information technology, a social business and its business model, and social business strategies of major companies.
The symposium started with keynote speeches delivered by Professor HongKyu Lee, RISTI, and Professor Hong-Tak Lim, RISTI, who discussed the role of technology in a social business. It was followed by plenary sessions led by CEOs who are running social businesses such as the Sharing and Technologies Incorporated Project, Simwon Technology, Ecojun Company, Underdogs, and the Farming Fund as well as by representatives from a social responsibility section of CJ management team and the social responsibility council of SK. In the future, these talks will serve as a medium to share their experiences in social businesses and to discuss the role of technology in the business. Some talks touched upon topics such as development of platforms for social innovation, social businesses employing disabled workers, and crowd funding for farming.
The Director of RISTI, Professor HongKyu Lee said, “The symposium will be the first to have people from leading companies in social businesses in Korea in one place.” He added, “This will be a great opportunity for anyone to know what will be the future of social businesses, which were created to solve the social problems caused by capitalism.”
The symposium was sponsored by the Ministry of Trade, Industry, and Energy of Korea.
2015.10.30 View 7436 -
Dong-Young Lee, a Doctoral Candidate, Receives the Best Paper Award
Dong-Young Lee, a Ph.D. candidate in the Mechanical Engineering Department, KAIST, received the Best Paper Award at the 18th International Conference on Composite Structures (ICCS). The event was held in Lisbon, Portugal, on June 15-18, 2015. Mr. Lee’s adviser is Professor Dai-Gil Lee of the same department.
The ICCS is held every other year, and is one of the largest and long-established conferences on composite materials and structures in the world. At this year’s conference, a total of 680 papers were presented, among which, two papers were chosen for the Best Paper Award, including Mr. Lee’s.
The paper, entitled “Gasket-integrated Carbon and Silicon Elastomer Composite Bipolar Plate for High-temperature PEMFC,” will be published in the September issue of Composite Structures which is one of the top journals in mechanical engineering as judged by the Google Scholar Metrics rankings.
Mr. Lee dropped the conventional method of PEMFC (Proton Exchange Membrane Fuel Cells) assembly and instead developed a gasket-integrated carbon and silicone elastomer composite bipolar plate. This technology significantly increased the energy efficiency of fuel cells and their productivity.
Mr. Lee said, “I would like to thank the many people who supported me, especially my Ph.D. adviser, Professor Dai-Gil Lee. Without their encouragement, I would have not won this award. I hope my research will contribute to solving energy problems in the future.”
In addition, Professor Joon-Woo Im from Chonbuk National University, Senior Researcher Il-Bum Choi from the Agency for Defense Development, and a fellow doctoral candidate Soo-Hyun Nam from KAIST participated in this research project.
2015.07.09 View 8060 -
Professor Sang Yup Lee Appointed Founding Board Member of Cell Systems
Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering at KAIST has been appointed a member of the founding editorial board of the newly established journal Cell Systems.
Cell Systems will be a sister journal of Cell, one of the three most prestigious scientific journals along with Nature and Science, that publishes a wide range of papers on biological engineering. The first issue of Cell Systems will be published this July.
Cell Systems plans to publish innovative discoveries, reviews of various research instruments, and research findings on integrated and quantified systems in the field of biology.
Professor Lee is a pioneer in metabolic engineering of microorganism with a focus on biopolymers and metabolites production. He is the editor-in-chief of Biotechnology Journal and serves on the editorial board of numerous international journals. He is also a member of the Global Agenda Council of the World Economic Forum and the Presidential Advisory Committee on Science and Technology in Korea.
Professor Lee said, “Cell Systems will present research findings that discuss whole biological systems methodically.” He continued, “I hope many research findings of Korean scholars will be published in Cell Systems, which will become a representative journal of systems biology and systems biological engineering.”
2015.02.13 View 8549