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The Medici Effect: Highly Flexible, Wearable Displays Born in KAIST
(Ph.D. candidate Seungyeop Choi)
How do you feel when technology you saw in a movie is made into reality? Collaboration between the electrical engineering and textile industries has made TVs or smartphone screens displaying on clothing a reality.
A research team led by Professor Kyung Cheol Choi at the School of Electrical Engineering presented wearable displays for various applications including fashion, IT, and healthcare. Integrating OLED (organic light-emitting diode) into fabrics, the team developed the most highly flexible and reliable technology for wearable displays in the world.
Recently, information displays have become increasingly important as they construct the external part of smart devices for the next generation. As world trends are focusing on the Internet of Things (IoTs) and wearable technology, the team drew a lot of attention by making great progress towards commercializing clothing-shaped ‘wearable displays’.
The research for realizing displays on clothing gained considerable attention from academia as well as industry when research on luminescence formed in fabrics was introduced in 2011; however, there was no technology for commercializing it due to its surface roughness and flexibility.
Because of this technical limitation, clothing-shaped wearable displays were thought to be unreachable technology. However, the KAIST team recently succeeded in developing the world’s most highly efficient, light-emitting clothes that can be commercialized.
The research team used two different approaches, fabric-type and fiber-type, in order to realize clothing-shaped wearable displays. In 2015, the team successfully laminated a thin planarization sheet thermally onto fabric to form a surface that is compatible with the OLEDs approximately 200 hundred nanometers thick. Also, the team reported their research outcomes on enhancing the reliability of operating fiber-based OLEDs. In 2016, the team introduced a dip-coating method, capable of uniformly depositing layers, to develop polymer light-emitting diodes, which show high luminance even on thin fabric.
Based on the research performance in 2015 and 2016, Ph.D. candidate Seungyeop Choi took the lead in the research team and succeeded in realizing fabric-based OLEDs, showing high luminance and efficiency while maintaining the flexibility of the fabric.
The long-term reliability of this wearable device that has the world’s best electrical and optical characteristics was verified through their self-developed, organic and inorganic encapsulation technology. According to the team, their wearable device facilitates the operation of OLEDs even at a bending radius of 2mm.
According to Choi, “Having wavy structures and empty spaces, fiber plays a significant role in lowering the mechanical stress on the OLEDs.”
“Screen displayed on our daily clothing is no longer a future technology,” said Professor Choi. “Light-emitting clothes will have considerable influence on not only the e-textile industry but also the automobile and healthcare industries.”
Moreover, the research team remarked, “It means a lot to realize clothing-shaped OLEDs that have the world’s best luminance and efficiency. It is the most flexible fabric-based light-emitting device among those reported. Moreover, noting that this research carried out an in-depth analysis of the mechanical characteristics of the clothing-spared, light-emitting device, the research performance will become a guideline for developing the fabric-based electronics industry.”
This research was funded by the Ministry of Trade, Industry and Energy and collaborated with KOLON Glotech, INC. The research performance was published in Scientific Reports in July.
(OLEDs operating in fabrics)
(Current-voltage-luminance and efficiency of the highly flexible, fabric-based OLEDs;Image of OLEDs after repetitive bending tests;Verification of flexibility through mechanical simulation)
2017.08.24 View 15073 -
Making Graphene Using Laser-induced Phase Separation
IBS & KAIST researchers clarify how laser annealing technology can lead to the production of ultrathin nanomaterials
All our smart phones have shiny flat AMOLED (active-matrix organic light-emitting diode) displays. Behind each single pixel of these displays hides at least two silicon transistors which are mass-manufactured using laser annealing technology. While the traditional methods to make the transistors use temperature above 1,000°C, the laser technique reaches the same results at low temperatures even on plastic substrates (melting temperature below 300°C). Interestingly, a similar procedure can be used to generate crystals of graphene. Graphene is a strong and thin nano-material made of carbon, its electric and heat-conductive properties have attracted the attention of scientists worldwide.
Professor Keon Jae Lee of the Materials Science and Engineering Department at KAIST and his research group at the Center for Multidimensional Carbon Materials within the Institute for Basic Science (IBS), as well as Professor Sung-Yool Choi of the Electrical Engineering School at KAIST and his research team discovered graphene synthesis mechanism using laser-induced solid-state phase separation of single-crystal silicon carbide (SiC). This study, available in Nature Communications, clarifies how this laser technology can separate a complex compound (SiC) into its ultrathin elements of carbon and silicon.
Although several fundamental studies presented the effect of excimer lasers in transforming elemental materials like silicon, the laser interaction with more complex compounds like SiC has rarely been studied due to the complexity of compound phase transition and ultra-short processing time.
With high resolution microscope images and molecular dynamic simulations, scientists found that a single-pulse irradiation of xenon chloride excimer laser of 30 nanoseconds melts SiC, leading to the separation of a liquid SiC layer, a disordered carbon layer with graphitic domains (about 2.5 nm thick) on top surface and a polycrystalline silicon layer (about 5 nm) below carbon layer. Giving additional pulses causes the sublimation of the separated silicon, while the disordered carbon layer is transformed into a multilayer graphene.
"This research shows that the laser material interaction technology can be a powerful tool for the next generation of two dimensional nanomaterials," said Professor Lee.
Professor Choi added: "Using laser-induced phase separation of complex compounds, new types of two dimensional materials can be synthesized in the future."
High-resolution transmission electron microscopy shows that after just one laser pulse of 30 nanoseconds, the silicon carbide (SiC) substrate is melted and separates into a carbon and a silicon layer. More pulses cause the carbon layer to organize into graphene and the silicon to leave as gas.
Molecular dynamics simulates the graphene formation mechanism. The carbon layer on the top forms because the laser-induced liquid SiC (SiC (l)) is unstable.
(Press Release by Courtesy of the Institute for Basic Science (IBS))
2016.12.01 View 11161 -
Graphene-Based Transparent Electrodes for Highly Efficient Flexible OLEDs
A Korean research team developed an ideal electrode structure composed of graphene and layers of titanium dioxide and conducting polymers, resulting in highly flexible and efficient OLEDs.
The arrival of a thin and lightweight computer that even rolls up like a piece of paper will not be in the far distant future. Flexible organic light-emitting diodes (OLEDs), built upon a plastic substrate, have received greater attention lately for their use in next-generation displays that can be bent or rolled while still operating.
A Korean research team led by Professor Seunghyup Yoo from the School of Electrical Engineering, KAIST and Professor Tae-Woo Lee from the Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH) has developed highly flexible OLEDs with excellent efficiency by using graphene as a transparent electrode (TE) which is placed in between titanium dioxide (TiO2) and conducting polymer layers. The research results were published online on June 2, 2016 in Nature Communications.
OLEDs are stacked in several ultra-thin layers on glass, foil, or plastic substrates, in which multi-layers of organic compounds are sandwiched between two electrodes (cathode and anode). When voltage is applied across the electrodes, electrons from the cathode and holes (positive charges) from the anode draw toward each other and meet in the emissive layer. OLEDs emit light as an electron recombines with a positive hole, releasing energy in the form of a photon. One of the electrodes in OLEDs is usually transparent, and depending on which electrode is transparent, OLEDs can either emit from the top or bottom.
In conventional bottom-emission OLEDs, an anode is transparent in order for the emitted photons to exit the device through its substrate. Indium-tin-oxide (ITO) is commonly used as a transparent anode because of its high transparency, low sheet resistance, and well-established manufacturing process. However, ITO can potentially be expensive, and moreover, is brittle, being susceptible to bending-induced formation of cracks.
Graphene, a two-dimensional thin layer of carbon atoms tightly bonded together in a hexagonal honeycomb lattice, has recently emerged as an alternative to ITO. With outstanding electrical, physical, and chemical properties, its atomic thinness leading to a high degree of flexibility and transparency makes it an ideal candidate for TEs. Nonetheless, the efficiency of graphene-based OLEDs reported to date has been, at best, about the same level of ITO-based OLEDs.
As a solution, the Korean research team, which further includes Professors Sung-Yool Choi (Electrical Engineering) and Taek-Soo Kim (Mechanical Engineering) of KAIST and their students, proposed a new device architecture that can maximize the efficiency of graphene-based OLEDs. They fabricated a transparent anode in a composite structure in which a TiO2 layer with a high refractive index (high-n) and a hole-injection layer (HIL) of conducting polymers with a low refractive index (low-n) sandwich graphene electrodes. This is an optical design that induces a synergistic collaboration between the high-n and low-n layers to increase the effective reflectance of TEs. As a result, the enhancement of the optical cavity resonance is maximized. The optical cavity resonance is related to the improvement of efficiency and color gamut in OLEDs. At the same time, the loss from surface plasmon polariton (SPP), a major cause for weak photon emissions in OLEDs, is also reduced due to the presence of the low-n conducting polymers.
Under this approach, graphene-based OLEDs exhibit 40.8% of ultrahigh external quantum efficiency (EQE) and 160.3 lm/W of power efficiency, which is unprecedented in those using graphene as a TE. Furthermore, these devices remain intact and operate well even after 1,000 bending cycles at a radius of curvature as small as 2.3 mm. This is a remarkable result for OLEDs containing oxide layers such as TiO2 because oxides are typically brittle and prone to bending-induced fractures even at a relatively low strain. The research team discovered that TiO2 has a crack-deflection toughening mechanism that tends to prevent bending-induced cracks from being formed easily.
Professor Yoo said, “What’s unique and advanced about this technology, compared with previous graphene-based OLEDs, is the synergistic collaboration of high- and low-index layers that enables optical management of both resonance effect and SPP loss, leading to significant enhancement in efficiency, all with little compromise in flexibility.” He added, “Our work was the achievement of collaborative research, transcending the boundaries of different fields, through which we have often found meaningful breakthroughs.”
Professor Lee said, “We expect that our technology will pave the way to develop an OLED light source for highly flexible and wearable displays, or flexible sensors that can be attached to the human body for health monitoring, for instance.”
The research paper is entitled “Synergistic Electrode Architecture for Efficient Graphene-based Flexible Organic Light-emitting Diodes” (DOI. 10.1038/NCOMMS11791). The lead authors are Jae-Ho Lee, a Ph.D. candidate at KAIST; Tae-Hee Han, a Ph.D. researcher at POSTECH; and Min-Ho Park, a Ph.D. candidate at POSTECH.
This study was supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF) through the Center for Advanced Flexible Display (CAFDC) funded by the Ministry of Science, ICT and Future Planning (MSIP); by the Center for Advanced Soft-Electronics funded by the MSIP as a Global Frontier Project; by the Graphene Research Center Program of KAIST; and by grants from the IT R&D Program of the Ministry of Trade, Industry and Energy of Korea (MOTIE).
Figure 1: Application of Graphene-based OLEDs
This picture shows an OLED with the composite structure of TiO2/graphene/conducting polymer electrode in operation. The OLED exhibits 40.8% of ultrahigh external quantum efficiency (EQE) and 160.3 lm/W of power efficiency. The device prepared on a plastic substrate shown in the right remains intact and operates well even after 1,000 bending cycles at a radius of curvature as small as 2.3 mm.
Figure 2: Schematic Device Structure of Graphene-based OLEDs
This picture shows the new architecture to develop highly flexible OLEDs with excellent efficiency by using graphene as a transparent electrode (TE).
2016.06.07 View 13808 -
Professor Keon-Jae Lee Lectures at IEDM and ISSCC Forums
Professor Keon-Jae Lee of KAIST’s Materials Science and Engineering Department delivered a speech at the 2015 Institute of Electrical and Electronics Engineers (IEEE) International Electron Devices Meeting (IEDM) held on December 7-9, 2015 in Washington, D.C.
He will also present a speech at the 2016 International Solid-State Circuits Conference scheduled on January 31-February 4, 2016 in San Francisco, California.
Both professional gatherings are considered the world’s most renowned forums in electronic devices and semiconductor technology. It is rare for a Korean researcher to be invited to speak at these global conferences.
Professor Lee was recognized for his research on flexible NAND chips. The Korea Times, an English language daily newspaper in Korea, reported on his participation in the forums and his recent work. An excerpt of the article follows below:
“KAIST Professor to Lecture at Renowned Tech Forums”
By Lee Min-hyung, The Korea Times, November 26, 2015
Recently he has focused on delivering technologies for producing flexible materials that can be applied to everyday life. The flexible NAND flash memory chips are expected to be widely used for developing flexible handsets. His latest research also includes flexible light-emitting diodes (LED) for implantable biomedical applications.
Lee is currently running a special laboratory focused on developing new flexible nano-materials. The research group is working to develop what it calls “self-powered flexible electronic systems” using nanomaterials and electronic technology.
Lee’s achievement with flexible NAND chips was published in the October edition of Nano Letters, the renowned U.S.-based scientific journal.
He said that flexible memory chips will be used to develop wearable computers that can be installed anywhere.
2015.11.26 View 11157 -
Open KAIST 2015
KAIST’s research environment and its most recent achievements were open to the public.
KAIST hosted “Open KAIST 2015” over two days from November 5-6, 2015 in which its 17 departments and three research centers were open to the public. The event is one of the largest events that KAIST holds, which permits such public viewings of its facilities. It is the eighth time it has taken place.
During this event, the departments and centers offered 64 programs including laboratory tours, research achievement exhibitions, department introductions, and special lectures.
The “Motion Capture System”of Professor Jun-Yong Noh’s lab (Graduate School of Culture Technology) drew particular attention.
The “Motion Capture System” expresses human and animal motion in three-dimensional (3D) space using infrared cameras and optic markers, which can then be applied to various industries such as movies, games, and animation. During the program, researchers themselves demonstrated the recording of the movement and its conversion into 3D characters.
Professor Yong-Hoon Cho’s laboratory introduced the scientific mechanism behind the Light Emitting Diode (LED) as well as its manufacturing process under the topic:“A to Z of LED Production.” The reserachers explained that how green LED is much more efficient compared to previous light sources and presented applications that how it is widely used in everyday life in smart phones, electronic displays, and other mobile gadgets.
Professor Jun-tani of the Department of Electronic and Electrical Engineering introduced “Humanoid Robot Nao’s Imitation of Human Motions.” Nao is an autonomous, programmable humanoid robot developed by a French robotics company based in Paris. Nao has an artificial neural circuit, which is the functional equivalent of a human brain, and can thus mimic the subject’s motions through learning.
In addition, Professor Hyo-Choong Bang (Department of Aerospace Engineering) in his lecture on “Unmanned Vehicle Research and Nano Satellites” and Professor Hyun Myung (Department of Civil and Environmental Engineering) on his lecture on “Future Civilization Robot System: the Jellyfish Elimination Robotic Swarm and the Wall-Climbing Drone” provided information on the progress of their respective research.
KAIST also displayed its most recent research achievements. A lecture on “Information Technology Convergence” offered a showroom for “Dr. M,” which is a mobile healthcare platform. Dr. M is a mobile healthcare system that collects and analyzes biosignals via a smart sensor attached to the human body that shows around 20 advanced technologies.
The Satellite Technology Research Center introduced the public to its “Get to Know Satellites” program on Korea’s first satellite “Our Star 1” in addition to showing the satellite assembly room and the satellite communication center.
Special lectures were also held for visitors. Professor Min-Hyuk Kim and Hye-Yeon Oh of the School of Computing talked about “Computer Graphics and Advanced Video Technology” and “Man and the Computer,” respectively, from the perspective of non-experts.
Another interesting feature was the “Wearable Computer Competition” in which college students held fashion shows with computers attached to their clothes.
Professor Jung Kwon Lee, the Dean of the College of Engineering, who led this event, said that “the Open KAIST, which is being held for the eighth time this year, is an excellent opportunity for the general public to experience KAIST’s research environment.” He hoped this could motivate young adults to widen their spectrum of scientific knowledge and raise affection for science.
2015.11.13 View 10720 -
Professors Sukbok Chang and Jang-Wook Choi Receive the 2015 Knowledge Award from the Korean Government
The Ministry of Science, ICT and Future Planning (MISP) of the Republic of Korea announced the 2015 Knowledge Awards on October 20, 2015. Two KAIST professors received the award.
Established in 2009, the awards are presented to Korean scientists whose publications have contributed to the international science community. Specifically, the MISP used the two biggest science databases, Science Citation Index Expanded (SCIE) and Scopus, to identify ten highly cited papers ranked in the top 1% by total citations in the past ten years.
Professor Sukbok Chang of Chemistry (left in the picture below) is a global authority in the field of catalytic hydrocarbon functionalization. His paper entitled “Palladium-catalyzed C-H Functionalization of Pyridine N-Oxides: Highly Selective Alkenylation and Direct Arylation with Unactivated Arenes,” which was published in the Journal of the American Chemical Society in 2008, was once selected by Thomson Reuters as one of the “Most Influential Research Papers of the Month.” In 2011, the American Chemical Society included his paper in the list of the top 20 research papers that were most frequently cited in the last three years.
Professor Jang-Wook Choi of the Graduate School of EEWS (Energy, Environment, Water, and Sustainability) has been known for his leading research in rechargeable battery, supercapacitor, and materials chemistry. In particular, his work on secondary fuel cells attracted significant attention from academia and industry in Korea. Professor Choi developed a super-thin flexible lithium-ion battery this year, thinner than a credit card, which lasts longer than the existing batteries and with greater performance. He also developed new electrode materials for next-generation sodium-ion and magnesium secondary fuel cells.
Professor Sukbok Chang (left) and Professor Jang-Wook Choi (right)
2015.10.23 View 11704 -
KAIST holds the 2015 KAIST-MIT-Technion International Symposium on Nano Science
The 2015 KAIST-MIT-Technion International Symposium on Nano Science was held on August 11, 2015 at the KAIST campus. The event took place under three subtopics: Materials for Production and Storage of Renewable Energy, Functional Materials, and Multiferroic Materials.
The joint symposium invited more than 300 experts in material science and engineering including ten speakers and panelists. From MIT (Massachusetts Institute of Technology), Professors Harry L. Tuller and Geoffrey S. Beach in the Department of Material Engineering, as well as Professor Gregory Rutledge in the Department of Chemical Engineering joined the symposium. Professor Avner Rothschild in the Department of Material Engineering and Professor Yair Ein-Eli in the Department of Chemical Engineering at Technion Institute of Technology in Israel also participated.
From KAIST, Professors Il-Doo Kim, Byong-Guk Park, and Yeon-Sik Jung in the Department of Materials Science and Engineering, Professor Chan-Ho Yang in the Department of Physics, and Professor Doh-Chang Lee in the Department of Chemical and Biomolecular Engineering spoke at the event. The list of topics included “Next Generation Lithium-Air Battery,” “Nano Materials for High Performance Energy Storage System,” and “Iron Oxide Nanoparticles Photoelectrode for the Conversion and Storage of Solar Energy.”
In its efforts to promote cooperation among the three universities, KAIST plans to send six students to MIT and one student to Technion for joint research.
Professor Il-Doo Kim, who organized the symposium said, “We believe this kind of international gathering will serve as an opportunity for scholars from leading universities to share their expertise in material science and help them better understand on the recent trends in nanoscience and its related technology.”
2015.08.12 View 8401 -
The College of Information Science & Technology names its Alumnus of the Year 2014
The College of Information Science & Technology (CIST), KAIST, selected Tae-Kyung Yoo, the Chief Executive Officer of Lumens, Inc., a Korean company producing semiconductors and light emitting diodes (LEDs), as its Alumnus of the Year 2014.
The award ceremony took place on September 19, 2014 at the KAIST Institute with the participation of the university’s senior management and students.
Mr. Yoo was recognized for his pioneering work to develop the LED industry in Korea as the next-generation growth engine for the nation’s economy.
After the ceremony, he gave a talk entitled “The Past and Future of the LED Industry: Its Important Role in the Change of Korean Industry.”
The CIST created the Alumnus of the Year 2014 award, for the first time this year, to appreciate its alumni’s contribution to the advancement of the industrial and academic sectors of Korean information science and technology, and it will continue presenting the award from this year onwards.
2014.09.22 View 7423 -
Opening of "Education Donation Center" for Knowledge Sharing
KAIST is a leader in knowledge-sharing services for the educationally underprivileged. KAIST held the opening ceremony of the Education Donation Center at its Munji Campus on July 4, 2014 and was appointed as a “2014 Chungcheong-Gangwon province model local education donation center” sponsored by the Education Ministry of Korea and Korea Foundation for the Advancement of Science and Creativity.
The Education Donation Center (EDC) will integrate programs run by the Chungcheong-Gangwon province education donation organizations and introduce them to local chapter organizations. The EDC will recommend new donation organizations to the organizations in need. To ensure efficient donation, the EDC will consult programs of donation organizations. The EDC will also suggest regionally suitable education donation programs. KAIST will provide three staff members, six graduate students, and one to manage the career counselor to the center.
Joo-Sung Lee of the Business & Technology Management Department is the professor in charge of the EDC. He explained, “The center is the medium between the newly participating education donation organizations and the demand organizations. I will invest every effort to provide high-quality educational benefits to educationally underprivileged people."
KAIST has also been running an education service group called ‘Midam Scholarship’, an online education donation group called ‘Chalk’, and science camp programs for youth to establish the sharing and collaboration culture of KAIST.
2014.07.10 View 9128 -
Professor Won Do Heo on LED Light Technology for Controlling Proteins in Living Cells
With the newly developed LED technology, Professor Won Do Heo at the College of Life Science and Bioengineering, KAIST, was able to suppress cell migration and division when cells are exposed to LED light. This suggests a breakthrough to apply in future cancer cell research.
Professor Heo talked about the impact of his research in the following excerpt from a news article:
“We are already conducting research on the spread of cancer, as well as brain science in animal models with the Light-Activated Reversible Inhibition by Assembled Trap. I believe this technology will be a breakthrough in investigating cancer treatments and the function of neurons in a complex neural network, which existing technologies have not been able to do.”
From EE Times Europe, June 19, 2014
“LED Light Technology Controls Proteins in Living Cells”
http://www.ledlighting-eetimes.com/en/led-light-technology-controls-proteins-in-living-cells.html?cmp_id=7&news_id=222909336
2014.06.22 View 8011 -
Professor Kyu-Young Whang receives the PAKDD Distinguished Contributions Award
Professor Kyu-Young Whag
Dr. Kyu-Young Whang, Distinguished Professor from the Department of Computer Science, KAIST, has received the 2014 Distinguished Contributions Award from the Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD). PAKDD is the leading academic international conference on data mining held in Asia/Pacific. This year’s international conference was held from 13th to 15th May at Tainan, Taiwan.
As a life member of the PAKDD Steering Committee, Professor Whang worked for the development of the data mining field in the Asia-Pacific region, and his contribution to the international database and data-mining field has been widely recognized.
The PAKDD Distinguished Contributions Award has been awarded to a total of six people until now, including Professor Whang, and he is the first Korean to receive this award.
Professor Whang has also a history of receiving the Outstanding Contributions Award in 2011 from the Database Systems for Advanced Applications (DASFAA), the prestigious database academic conference in the Asia-Pacific region. The database and data mining field in the region was barren 20 years ago, but through the efforts and contributions of many researchers, including Professor Whang, it has now leapt to the level of being the equal of North American and European researchers.
In fact, three academic organizations in the current international database field are led by professors in the Asia-Pacific region. The IEEE ICDE (Institute of Electrical and Electronics Engineers Technical Committee on Data Engineering) is led by Professor Whang; the VLDB (Very Large Data Base) Endowment by Professor Beng Chin Ooi from National University of Singapore (NUS); and the ACM SIGMOD (Association for Computing Machinery Special Interest Group on Management of Data) by Professor Don Kossmann from ETH Zurich.
2014.05.26 View 8877 -
An Education Donation Club at KAIST Received the Education Minister's Award in 2013
Chalk, one of the student clubs at KAIST, shares knowledge by providing free online classes to teenage students in Korea via Internet.
Chalk, a KAIST student club which donates their educational knowledge, received an award from the Education Minister of the Republic of Korea at the 2nd Donation for Education Award held on December 16th, 2013 at the Plaza Hotel in Seoul.
The Donation for Eduation Award aims to find and reward corporations, organizations, and individuals, which have actively contributed to growing the dreams and talents of students, as well as revitalizing the culture of donation for education. It has been awarded by the Ministry of Education since 2012 to promote the awareness and participation of students for education.
Chalk provides free online video lectures on www.playchalk.com and runs a mentoring-based education program. The club has been recognized for offering online courses, math and science classes in particular, to teenage students who are from socially and economically less privileged backgrounds.
Chalk was founded by five KAIST students in 2011. Their ultimate goal is to create a society where students can fully enjoy the benefits of education, regardless of their economic conditions. About 60 undergraduate students currently participate in the club, with more than 5,000 students attending over 160 lectures without any cost.
2014.01.07 View 9769