MEMS
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Professor Hyunjoo Jenny Lee to Co-Chair IEEE MEMS 2025
Professor Hyunjoo Jenny Lee from the School of Electrical Engineering has been appointed General Chair of the 38th IEEE MEMS 2025 (International Conference on Micro Electro Mechanical Systems). Professor Lee, who is 40, is the conference’s youngest General Chair to date and will work jointly with Professor Sheng-Shian Li of Taiwan’s National Tsing Hua University as co-chairs in 2025.
IEEE MEMS is a top-tier international conference on microelectromechanical systems and it serves as a core academic showcase for MEMS research and technology in areas such as microsensors and actuators.
With over 800 MEMS paper submissions each year, the conference only accepts and publishes about 250 of them after a rigorous review process recognized for its world-class prestige. Of all the submissions, fewer than 10% are chosen for oral presentations.
2022.04.18 View 4644 -
Electrosprayed Micro Droplets Help Kill Bacteria and Viruses
With COVID-19 raging around the globe, researchers are doubling down on methods for developing diverse antimicrobial technologies that could be effective in killing a virus, but harmless to humans and the environment.
A recent study by a KAIST research team will be one of the responses to such efforts. Professor Seung Seob Lee and Dr. Ji-hun Jeong from the Department of Mechanical Engineering developed a harmless air sterilization prototype featuring electrosprayed water from a polymer micro-nozzle array. This study is one of the projects being supported by the KAIST New Deal R&D Initiative in response to COVID-19. Their study was reported in Polymer.
The electrosprayed microdroplets encapsulate reactive oxygen species such as hydroxyl radicals, superoxides that are known to have an antimicrobial function. The encapsulation prolongs the life of reactive oxygen species, which enable the droplets to perform their antimicrobial function effectively. Prior research has already proven the antimicrobial and encapsulation effects of electrosprayed droplets.
Despite its potential for antimicrobial applications, electrosprayed water generally operates under an electrical discharge condition, which can generate ozone. The inhalation of ozone is known to cause damage to the respiratory system of humans. Another technical barrier for electrospraying is the low flow rate problem. Since electrospraying exhibits the dependence of droplet size on the flow rate, there is a limit for the amount of water microdroplets a single nozzle can produce.
With this in mind, the research team developed a dielectric polymer micro-nozzle array to perform the multiplexed electrospraying of water without electrical discharge. The polymer micro-nozzle array was fabricated using the MEMS (Micro Electro-Mechanical System) process. According to the research team, the nozzle can carry five to 19 micro-nozzles depending on the required application.
The high aspect ratio of the micro-nozzle and an in-plane extractor were proposed to concentrate the electric field at the tip of the micro-nozzle, which prevents the electrical discharge caused by the high surface tension of water. A micro-pillar array with a hydrophobic coating around the micro-nozzle was also proposed to prevent the wetting of the micro-nozzle array.
The polymer micro-nozzle array performed in steady cone jet mode without electrical discharge as confirmed by high-speed imaging and nanosecond pulsed imaging. The water microdroplets were measured to be in the range of six to 10 μm and displayed an antimicrobial effect on Escherichia coli and Staphylococcus aureus.
Professor Lee said, “We believe that this research can be applied to air conditioning products in areas that require antimicrobial and humidifying functions.”
Publication:
Jeong, J. H., et al. (2020) Polymer micro-atomizer for water electrospray in the cone jet mode. Polymer. Vol. No. 194, 122405. Available online at https://doi.org/10.1016/j.polymer.2020.122405
Profile: Seung Seob Lee, Ph.D.
sslee97@kaist.ac.kr
http://mmst.kaist.ac.kr/
Professor
Department of Mechanical Engineering (ME)
Korea Advanced Institute of Science and Technology (KAIST)
https://www.kaist.ac.kr
Daejeon 34141, Korea
Profile: Ji-hun Jeong, Ph.D.
jiuni6022@kaist.ac.kr
Postdoctoral researcher
Department of Mechanical Engineering (ME)
Korea Advanced Institute of Science and Technology (KAIST)
https://www.kaist.ac.kr
Daejeon 34141, Korea
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2020.12.21 View 10845 -
Professor Kyoungsik Yu Receives the Young IT Engineer Award from IEEE and IEIE of Korea
Professor Kyoungsik Yu of KAIST’s Department of Electrical Engineering is the recipient of this year’s Young IT (Information Technology) Engineer Award that was co-hosted by the Institute of Electrical and Electronics Engineers (IEEE), the Institute of Electronics Engineers of Korea (IEIE), and Haedong Science Culture Foundation in Korea. The award was presented on June 22, 2015 at The Ramada Plaza Jeju Hotel on Jeju Island, Korea.
The Young IT Engineer Award is given to emerging scientists who have made significant contributions to the advancement of technology, society, environment, and creative education.
Professor Yu's main research interests are IT, energy, and imaging through miniaturization and integration of optoelectronic devices. His contribution to academic and technological development is reflected in his publication of more than 100 papers in international journals and conferences, which were cited over 2,200 times.
Professor Yu said, “I’m honored to receive this award and am encouraged by it. I also find the award meaningful because the United Nations has designated this year as the “International Year of Light and Light-based Technologies,” the field I have been involved in as a researcher.”
In addition to Korea, the IEEE has jointly hosted and presented this award to researchers in countries such as Chile, Ecuador, Peru, Singapore, and Italy.
2015.06.22 View 10004 -
Professor Young-Ho Cho elected as head of international academic conference
KAIST’s Professor Young-Ho Cho of the Department of Bio and Brain Engineering was appointed as the head of the PowerMems (Power Micro Electro Mechanical Systems) symposium to be held at Se-Jong Hotel in Seoul from November 15-18, 2011.
Professor Jo is America’s first engineering doctor in the field of MEMS and is the founding member of the BSAC (Berkeley Sensor and Actuator Center), the start of the MEMS technology.
PowerMEMS is the core of green growth and next generation energy production. It focuses on harvesting energy from minute vibrations or renewable energy sources such as sunlight or plants to harvest and store energy via micro or even nano size systems.
The symposium was first held in 2000, and it is where leading experts in the field share papers on the production and harvesting energy in the micro scale.
2011.01.14 View 10357