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An Exploratory Study on Smartphone Abuse among College Students
Professor Uichin Lee Professor Uichin Lee of the Department of Knowledge Service Engineering, KAIST, and his research team developed a system that automatically diagnoses the levels of smartphone addiction based on an analysis of smartphone use records. Professor Lee investigated the usage patterns of 95 smartphone users (college students) by conducting surveys and interviews and collecting logged data. The research team divided participants into “risk” and “non-risk” groups based on a self-reported rating scale to evaluate their abuse of smartphones. As a result, 36 students were categorized as “high risk” and 59 were categorized as “low risk.” The researchers collected over 50,000 hours of smartphone use encompassing power levels, screen, battery status, application use, internet use, calling, and texting. The results showed that the “high risk” group used only 1~2 applications, focusing on mobile messengers (Kakotalk, etc.) and SNS (Facebook, etc.). In addition, a relationship was found between alarm function and addiction levels. Users who set alarms for Kakaotalk messages and SNS comments used smartphones for an additional 38 minutes per day on average. Results also showed that “high risk” students were on their smartphones for 4 hours and 13 minutes per day, 46 minutes longer than “low risk” students who used smartphones for 3 hours and 27 minutes. The difference was prevalent during 6 am and noon, and 6pm and midnight. In addition, “high risk” students accessed their smartphones 11.4 times more than “low risk” students. Based on the collected data, Professor Lee developed an automatic system that distinguished users into “high risk” or “low risk” categories with 80% accuracy. The new system is expected to give an early diagnosis of addiction to smartphone users, thereby allowing for early treatment and intervention before the user becomes addicted. Professor Lee commented that, "the conventional addiction analysis based on self-analysis surveys did not provide real-time data and were largely inaccurate. The new system overcomes these limitations through data science and personal big data analysis" and that he is "developing an application that monitors smartphone abuse." Figure 1. Usage amount: overall and application-specific results Figure 2. Usage frequency: overall and application-specific results Figure 3. Overall diurnal usage time and frequency
2014.06.05
View 7948
KAIST-Coursera Course: Introduction to Acoustics Engineering
Professor Yang-Hann Kim of Mechanical Engineering at KAIST has been offering an online course entitled “Introduction to Acoustics” on Corsera, the world’s largest MOOCs (Massive Open Online Courses) provider, from May 12th. KAIST offered three Coursera classes during a spring semester in 2014, and Professor Kim’s course was the first one provided by the university to global learners. Professor Kim has immersed himself in research and education on acoustics engineering for the past 30 years. His Coursera class has received positive responses from students, and some important data follows below: For the past ten days, over 6,000 students from all around the world have enrolled the class. The student population consists of 33% in North America (United States and Canada), 32% in Europe, 23% in Asia, 8% in South America, and 2% in Africa. Arranged in order of countries, 25% of access originated from the United States, 8% from India, and 3% or 4% each from Brazil, Britain, Spain, Canada, Germany, Mexico, China, Russia, and France, and 2% from Korea. The other two KAIST-Coursera classes are “Supply Chain Management: A Learning Perspective” and “Introduction to Light, Color, and Life.” For more information, please visit https://www.coursera.org/kaist.
2014.05.25
View 10053
KAIST Made Great Improvements of Nanogenerator Power Efficiency
The energy efficiency of a piezoelectric nanogenerator developed by KAIST has increased by almost 40 times, one step closer toward the commercialization of flexible energy harvesters that can supply power infinitely to wearable, implantable electronic devices. NANOGENERATORS are innovative self-powered energy harvesters that convert kinetic energy created from vibrational and mechanical sources into electrical power, removing the need of external circuits or batteries for electronic devices. This innovation is vital in realizing sustainable energy generation in isolated, inaccessible, or indoor environments and even in the human body. Nanogenerators, a flexible and lightweight energy harvester on a plastic substrate, can scavenge energy from the extremely tiny movements of natural resources and human body such as wind, water flow, heartbeats, and diaphragm and respiration activities to generate electrical signals. The generators are not only self-powered, flexible devices but also can provide permanent power sources to implantable biomedical devices, including cardiac pacemakers and deep brain stimulators. However, poor energy efficiency and a complex fabrication process have posed challenges to the commercialization of nanogenerators. Keon Jae Lee, Associate Professor of Materials Science and Engineering at KAIST, and his colleagues have recently proposed a solution by developing a robust technique to transfer a high-quality piezoelectric thin film from bulk sapphire substrates to plastic substrates using laser lift-off (LLO). Applying the inorganic-based laser lift-off (LLO) process, the research team produced a large-area PZT thin film nanogenerators on flexible substrates (2cm x 2cm). “We were able to convert a high-output performance of ~250 V from the slight mechanical deformation of a single thin plastic substrate. Such output power is just enough to turn on 100 LED lights,” Keon Jae Lee explained. The self-powered nanogenerators can also work with finger and foot motions. For example, under the irregular and slight bending motions of a human finger, the measured current signals had a high electric power of ~8.7 μA. In addition, the piezoelectric nanogenerator has world-record power conversion efficiency, almost 40 times higher than previously reported similar research results, solving the drawbacks related to the fabrication complexity and low energy efficiency. Lee further commented, “Building on this concept, it is highly expected that tiny mechanical motions, including human body movements of muscle contraction and relaxation, can be readily converted into electrical energy and, furthermore, acted as eternal power sources.” The research team is currently studying a method to build three-dimensional stacking of flexible piezoelectric thin films to enhance output power, as well as conducting a clinical experiment with a flexible nanogenerator. This research result, entitled “Highly-efficient, Flexible Piezoelectric PZT Thin Film Nanogenerator on Plastic Substrates,” was published as the cover article of the April issue of Advanced Materials. (http://onlinelibrary.wiley.com/doi/10.1002/adma.201305659/abstract) YouTube Link: http://www.youtube.com/watch?v=G_Fny7Xb9ig Over 100 LEDs operated by self-powered flexible piezoelectric thin film nanogenerator Flexible PZT thin film nanogenerator using inorganic-based laser lift-off process Photograph of large-area PZT thin film nanogenerator (3.5cm × 3.5cm) on a curved glass tube and 105 commercial LEDs operated by self-powered flexible piezoelectric energy harvester
2014.05.19
View 14889
KAIST Offers Massive Open Online Courses (MOOCs) to Global Learners
Global learners can now take premier engineering courses offered by the Korea Advanced Institute of Science and Technology (KAIST) through one of the leading online education providers, Coursera. KAIST has begun offering three massive open online courses (MOOCs) to reach millions of students on the Internet. Collaborating with Coursera to provide a MOOC platform, KAIST will extend its excellence in science and engineering to a broader global audience while using technology to enhance the classroom experience for its students on campus. Three courses are offered in the following areas: sound engineering (as of May 12th); an interdisciplinary approach of physics, life science, and industrial design (to be launched in late May); and business management (to be launched in June). Professor Yang-Hann Kim of Mechanical Engineering, an instructor who will teach the “Introduction to Acoustics” course, explained his decision to participate in MOOCs: “I have been teaching acoustics engineering at KAIST over the past 30 years. I wanted to share my knowledge and expertise with researchers and students who are otherwise unable to receive a quality education in a traditional education setting. This is a great opportunity to offer my talent to the global community.” The Center for Excellence in Learning & Teaching at KAIST has worked with professors to design online courses, record video lectures, and create student assignments. Students will learn in 10- to 15-minute lesson segments over a ten-week period, with an anticipated workload of 4-6 hours per week, on average. KAIST made a partnership agreement with Coursera in October 2013 to provide free online courses for Korean and global learners. Beginning with three courses, the university plans to increase the number of classes incrementally. To get more information about KAIST’s MOOC offerings, please visit https://www.coursera.org/kaist. Founded by two computer science professors at Stanford University in 2012, Coursera offers free online education to anyone interested in learning and equipped with the Internet, including students, professionals, and life-long learners, to empower them with knowledge and skills. As of April 2014, Coursera has 7.1 million users in 641 courses from 108 institutions.
2014.05.14
View 10189
Clear Display Technology Under Sunlight Developed
The late Professor Seung-Man Yang The last paper of the late Professor Seung-Man Yang, who was a past master of colloids and fluid mechanics Practical patterning technology of the next generation optical materials, photonic crystals The mineral opal does not possess any pigments, but it appears colorful to our eyes. This is because only a particular wavelength is reflected due to the regular nano-structure of its surface. The material that causes selective reflection of the light is called photonic crystals. The deceased Professor Seung-Man Yang and his research team from KAIST’s Chemical and Biomolecular Engineering Department ha ve developed micro-pattern technology using photolithographic process. This can accelerate the commercialization of photonic crystals, which is hailed as the next generation optics material. The research results were published in the April 16th edition of Advanced Materials, known as the most prestigious world-renowned journal in the field of materials science. The newly developed photonic crystal micro-pattern could be used as a core material for the next generation reflective display that is clearly visible even under sunlight. Since it does not require a separate light source, a single charge is enough to last for several days. Until now, many scientists have endeavored to make photonic crystals artificially, however, most were produced in a lump and therefore lacked efficiency. Also, the low mechanical stability of the formed structure prevented from commercialization. In order to solve these problems, the research team has copied the nano-structure of opals. Glass beads were arranged in the same nano-structure as the opal on top of the photoresist material undergoing photocuring by ultraviolet light. The glass beads were installed in the photoresist materials, and UV light was selectively exposed on micro regions. The remaining region was developed by photolithographic process to successfully produce photonic crystals in micro-patterns. The co-author of the research, KAIST Chemical and Biomolecular Engineering Department’s Professor Sin-Hyeon Kim, said, “Combining the semiconductor process technology with photonic crystal pattern technology can secure the practical applications for photonic crystals.”He also predicted “This technology can be used as the key optical material that configures the next generation reflective color display device with very low power consumption.” The late Professor Seung-Man Yang was a world-renowned expert in the field of colloids and fluid mechanics. Professor Yang published over 193 papers in international journals and continued his research until his passing in last September. He received Du Pont Science and Technology Award in 2007, KAIST Person of the Year 2008, Gyeong-Am Academy Award in 2009, as well as the President’s Award of the Republic of Korea in March 2014. The researchers devoted the achievement of this year’s research to Professor Yang in his honor. Research was conducted by KAIST Photonic-fluidic Integrated Devices Research Team, as a part of the Creative Research Program funded by the Ministry of Science, ICT and Future Planning, Republic of Korea. Figure 1. Opal [left] and the nano glass bead arrangement structure within the opal [right] Figure 2. Process chart of the photonic crystal micro-pattern formation based on photolithography Figure 3. Opal structure [left] and inverted structure of the opal [right] Figure 4. Photonic crystal micro-pattern in solid colors Figure 5. Photonic crystal micro-pattern that reflects two different crystals (Red, Green) [left] and pixelated pattern of photonic crystal in three primary colors (Red, Green, Blue) [right] that is applicable to reflective displays
2014.05.14
View 12934
KAIST leaps to 2nd place in 2014 QS Asian University Rankings
The highest record ever made by a Korean university since the rankings were published in 2009 KAIST jumped four places to rank #2 from #6 last year, following the National University of Singapore In the "2014 Quacquarelli Symonds (QS) University Rankings: Asia," KAIST advanced four places compared to 2013 and was ranked 2nd best university in Asia. QS, an English institution for global university evaluation, and Chosun Newspaper, a leading daily newspaper in Korea, announced the results of the QS Asia University Rankings on April 12th. The result was a record high for a Korean University since the start of annual rankings in 2009. KAIST has consistently ranked within the top ten, ranking 7th in 2009 and 2012, and 6th in 2013. The sudden jump from the 6th to the 2nd place was attributed to the increase in the number of published papers per professor and the number of citations per paper. In particular, KAIST received high marks for research contributions, which shows that the young faculty members hired since 2006 is now becoming very productive. For details regarding the 2014 QS University Rankings: Asia, please visit http://www.topuniversities.com/university-rankings-articles/asian-university-rankings/top-10-universities-asia-2014. President Steve Kang of KAIST commented, “We are reaping the rewards of recruiting some of the most promising young professors. KAIST will continue its development towards becoming one of the top ten universities in the world.” The QS Asia University Rankings have evaluated higher education institutions of Asia for the past six years. It evaluates 491 universities across 17 nations. Criterion for evaluation includes academic evaluation (30%), number of published papers per staff (15%), citation frequency (15%), number of students per staff (20%), alumni reputation, and internationalization (10%). Please also refer to the Korean-American Science and Technology News (KASTN), dated June 4, 2014, for further information on the rankings. Another Rankings, Pages 4-5 Chosun Ilbo, May 12, 2014 “Chosun-QS Rankings” KAIST Soars to 2nd Place in Asian Rakings http://www.phy.duke.edu/~myhan/b_14-12.pdf
2014.05.14
View 13677
KAIST ranked third in the top 100 universities under 50 years old
The Times Higher Education (THE) released on April 30, 2014 its annual ranking of 100 top universities whose history is under 50 years. KAIST placed 3rd, holding the same spot from last year. The (THE) 100 Under 50 ranking used 13 indicators across five factors to measure the performance of institutions: research, citations, teaching, international outlook, and industry income. The indicators included research volume and income, reputation, learning environment, staff-to-student ratio, scholarly papers produced, and the percentage of international staff as part of the institution’s faculty. Phil Baty, editor of the Times ranking, compared younger and older universities as follows: “Young universities are free to be more agile, lean, and risk-taking, giving them an advantage in a rapidly changing global marketplace. They are also free to offer innovative teaching and focus their research in niche, high-impact areas.” KAIST and Pohang University of Science and Technology (ranked first) are the only Korean universities that made the ranking list. For the full list, please go to: http://www.timeshighereducation.co.uk/world-university-rankings/2014/one-hundred-under-fifty This information was provided by the Times Higher Education 100 Under 50.
2014.05.03
View 11354
Binding Regulatory Mechanism of Protein Biomolecules Revealed
Professor Hak-Sung Kim A research team led by Professor Hak-Sung Kim of Biological Sciences, KAIST, and Dr. Mun-Hyeong Seo, KAIST, has revealed a regulatory mechanism that controls the binding affinity of protein’s biomolecules, which is crucial for the protein to recognize molecules and carry out functions within the body. The research results were published in the April 24th online edition of Nature Communications. The protein, represented by enzyme, antibody, or hormones, specifically recognizes a variety of biomolecules in all organisms and implements signaling or immune response to precisely adjust and maintain important biological processes. The protein binding affinity of biomolecules plays a crucial role in determining the duration of the bond between two molecules, and hence to determine and control the in-vivo function of proteins. The researchers have noted that, during the process of proteins’ recognizing biomolecules, the protein binding affinity of biomolecules is closely linked not only to the size of non-covalent interaction between two molecules, but also to the unique kinetic properties of proteins. To identify the basic mechanism that determines the protein binding affinity of biomolecules, Professor Kim and his research team have made mutation in the allosteric site of protein to create a variety of mutant proteins with the same chemical binding surface, but with the binding affinity vastly differing from 10 to 100 times. The allosteric site of the protein refers to a region which does not directly bind with biomolecules, but crucially influences the biomolecule recognition site. Using real-time analysis at the single-molecule level of unique kinetic properties of the produced mutant proteins, the researchers were able to identify that the protein binding affinity of biomolecules is directly associated with the protein’s specific kinetic characteristics, its structure opening rate. Also, by proving that unique characteristics of the protein can be changed at the allosteric site, instead of protein’s direct binding site with biomolecules, the researchers have demonstrated a new methodology of regulating the in-vivo function of proteins. The researchers expect that these results will contribute greatly to a deeper understanding of protein’s nature that governs various life phenomena and help evaluate the proof of interpreting protein binding affinity of biomolecules from the perspective of protein kinetics. Professor Kim said, “Until now, the protein binding affinity of biomolecules was determined by a direct interaction between two molecules. Our research has identified an important fact that the structure opening rate of proteins also plays a crucial role in determining their binding affinity.” [Picture] A correlation graph of opening rate (kopening) and binding affinity (kd) between protein’s stable, open state and its unstable, partially closed state.
2014.05.02
View 10229
Leon Chua, the founder of the circuit theory called "memristor," gave a talk at KAIST
Dr. Leon Ong Chua is a circuit theorist and professor in the Department of Electrical Engineering and Computer Sciences at the University of California, Berkeley. He visited KAIST on April 16, 2014 and gave a talk entitled “Memristor: New Device with Intelligence.” Dr. Chua contributed to the development of nonlinear circuit theory and cellular neural networks (CNN). He was also the first to conceive of memristor which combines the characteristics of memory and resistor. Memristor is a type of resistor, remembering the direction and charge of electrical current that has previously flowed through the resistor. In other words, memristor can retain memory without power. Today, memristor is regarded as the fourth fundamental circuit element, together with capacitors, inductors, and resistors. In 2008, researchers at Hewlett-Packard (HP) Labs developed the first working model of memristor, which was reported in Nature (May 1st , 2008). In addition, Dr. Chua is an IEEE fellow and has received numerous awards including the IEEE Kirchhoff Award, the IEEE Neural Network Pioneer Award, the IEEE Third Millennium Medal, and the Top 15 Most Cited Author in Engineering Award.
2014.04.21
View 10514
Thermoelectric generator on glass fabric for wearable electronic devices
Wearable computers or devices have been hailed as the next generation of mobile electronic gadgets, from smart watches to smart glasses to smart pacemakers. For electronics to be worn by a user, they must be light, flexible, and equipped with a power source, which could be a portable, long-lasting battery or no battery at all but a generator. How to supply power in a stable and reliable manner is one of the most critical issues to commercialize wearable devices. A team of KAIST researchers headed by Byung Jin Cho, a professor of electrical engineering, proposed a solution to this problem by developing a glass fabric-based thermoelectric (TE) generator that is extremely light and flexible and produces electricity from the heat of the human body. In fact, it is so flexible that the allowable bending radius of the generator is as low as 20 mm. There are no changes in performance even if the generator bends upward and downward for up to 120 cycles. To date, two types of TE generators have been developed based either on organic or inorganic materials. The organic-based TE generators use polymers that are highly flexible and compatible with human skin, ideal for wearable electronics. The polymers, however, have a low power output. Inorganic-based TE generators produce a high electrical energy, but they are heavy, rigid, and bulky. Professor Cho came up with a new concept and design technique to build a flexible TE generator that minimizes thermal energy loss but maximizes power output. His team synthesized liquid-like pastes of n-type (Bi2Te3) and p-type (Sb2Te3) TE materials and printed them onto a glass fabric by applying a screen printing technique. The pastes permeated through the meshes of the fabric and formed films of TE materials in a range of thickness of several hundreds of microns. As a result, hundreds of TE material dots (in combination of n and p types) were printed and well arranged on a specific area of the glass fabric. Professor Cho explained that his TE generator has a self-sustaining structure, eliminating thick external substrates (usually made of ceramic or alumina) that hold inorganic TE materials. These substrates have taken away a great portion of thermal energy, a serious setback which causes low output power. He also commented, "For our case, the glass fabric itself serves as the upper and lower substrates of a TE generator, keeping the inorganic TE materials in between. This is quite a revolutionary approach to design a generator. In so doing, we were able to significantly reduce the weight of our generator (~0.13g/cm2), which is an essential element for wearable electronics." When using KAIST's TE generator (with a size of 10 cm x 10 cm) for a wearable wristband device, it will produce around 40 mW electric power based on the temperature difference of 31 °F between human skin and the surrounding air. Professor Cho further described about the merits of the new generator: "Our technology presents an easy and simple way of fabricating an extremely flexible, light, and high-performance TE generator. We expect that this technology will find further applications in scale-up systems such as automobiles, factories, aircrafts, and vessels where we see abundant thermal energy being wasted." This research result was published online in the March 14th issue of Energy & Environmental Science and was entitled "Wearable Thermoelectric Generator Fabricated on Glass Fabric." Youtube Link: http://www.youtube.com/watch?v=BlN9lvEzCuw&feature=youtu.be [Picture Captions] Caption 1: The picture shows a high-performance wearable thermoelectric generator that is extremely flexible and light. Caption 2: A thermoelectric generator developed as a wristband. The generator can be easily curved along with the shape of human body. Caption 3: KAIST’s thermoelectric generator can be bent as many as 120 times, but it still shows the same high performance.
2014.04.21
View 20817
KAIST and Hancom Inc. Join Hands for Software Development Projects
KAIST (Steve Kang) and Hancom Inc. (Sang-Chul Kim) made an agreement on the 8th of April for a partnership to jointly develop software industry. After the ceremony, a TFT (Task Force Team) for industry-university collaboration was established and a seminar to discuss cooperative projects ensued. KAIST and Hancom Inc. agreed to cooperate in three main areas at the seminar. They included enhancing manpower in the Korean software industry, the technical development of software applications, and creating a business model for the expansion of the Korean software market globally. KAIST president Steve Kang said, "Noteworthy research achievements will result from this great partnership with Hancom Inc. I believe this alliance will play an important role in the development of Korean software industry." “The combination of KAIST's excellent talents and Hancom's software know-hows will produce market-winning results. We hope that mutual developments from the two organizations through this practical industry-university collaboration will inspire many software companies to follow suit,” said Sang-Chul Kim, the president of Hancom Inc.
2014.04.11
View 7972
Strawberries Delivered by A Miniature Drone at KAIST Spring Festival
The "HAPPY KAIST 2014 Spring Festival" held at KAIST from 4th April The Cherry Blossoms Festival under the theme of "Cherry Blossoms: Light and Fantasy" held on 4th April The Strawberry Party with strawberries exclusively delivered by a miniature drone on 11th April KAIST is holding a spring festival from April 4th through 11th. As a part of the "HAPPY KAIST 2014" event, cherry blossoms festival and strawberry party will be held at KAIST campus starting on April 4th. This event has been organized with the purpose of creating a new culture and tradition for members of KAIST to unite. Faculty members, staff, and students have all contributed to making the festival a success. The cherry blossoms festival, held under the theme of "Cherry Blossoms: Light and Fantasy," takes place at the road in front of the KAIST north dormitory, which provides a spectacular view of cherry blossom trees. It begins on the night of April 4th and continues until the 8th of April. Around the cherry blossom tree road displays an art exhibition by the Design Rangers, a student club of graduate and doctorate students from the Department of Industrial Design at KAIST. The exhibition includes the "Fantasy Cherry Blossoms" and "Let’s Walk Together." Following on the 11th will be the "Strawberry Party" to take place throughout the campus. The strawberry party began in 1995 in order to help the local strawberry farmers. Now, it has become KAIST’s own unique tradition attended by faculty, student clubs, and laboratory members. This year, the fruit party becomes a unique event in that there will be a demonstration of strawberry delivery by an unmanned vehicle or an unmanned aerial vehicle (a miniature drone). When a customer orders strawberries via a smart phone application, the user's current location is sent to the central system of an unmanned vehicle. Either the unmanned vehicle (UV) transports strawberries or for places inaccessible by the UV such as on a lawn, the drone delivers the fruit to the customer . This demonstration has been organized by Professor Hyunchul Shim from the Department of Aerospace Engineering at KAIST. Professor Shim said, “If the unmanned logistics system, such as the one being demonstrated at the Strawberry Party, is commercialized, both cost and time in the logistics industry can be significantly reduced.” The HAPPY KAIST 2014, organized by the College of Engineering, is an annual event, consisting of a total of five programs, with the purpose to make the campus happier and healthier.
2014.04.07
View 9949
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