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Top 10 Emerging Technologies of 2017
The World Economic Forum’s Expert Network and Global Future Councils in collaboration with Scientific American and its Board of Advisors announced the top 10 emerging technologies of 2017 on June 26 in Dalian, China where the 2017 Summer Davos Forum is being held. Each technology was chosen for its potential to improve lives, transform industries, and safeguard the planet. The KAIST delegation, headed by President Sung-Chul Shin, is participating in the forum’s diverse activities including IdeasLab and GULF (Global University Leaders Forum). KAIST is the only Korean representative participating in the IdeasLab. KAIST Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering, director of KAIST Institute, has served as a committee member of the Global Agenda Council on Emerging Technologies since 2012 and Global Future Council on the Fourth Industrial Revolution. He also chairs the Global Future Council on Biotechnologies. Professor Lee said, “Very diverse technological breakthroughs were proposed for the final list of candidates. We made the final selections through very in-depth discussion with experts in each field. We focused on the technologies which have a level of maturity that will enable them to be adopted widely within three to five years." The top 10 emerging technologies are (courtesy from https:// www.weforum.org/agenda/2017/06/these-are-the-top-10-emerging-technologies-of-2017): 2017 10대 기술. 1. Liquid biopsies Liquid biopsies mark a step forward in the fight against cancer. First, they are an alternative where traditional tissue-based biopsies are not possible. Second, they provide a full spectrum of information compared to tissue samples, which only reflect the information available in the sample. Lastly, by homing in on circulating-tumor DNA (ctDNA), genetic material that routinely finds its way from cancer cells into the bloodstream, disease progression or resistance to treatment can be spotted much faster than otherwise relying on symptoms or imaging. 2. Harvesting clean water from air The ability to extract clean water from air is not new, however existing techniques require high moisture levels and a lot of electricity. This is changing. A team from MIT and University of California, Berkeley has successfully tested a process using porous crystals that convert the water using no energy at all. 3. Deep learning for visual tasks Computers are beginning to recognize images better than humans. Thanks to deep learning, an emerging field of artificial intelligence, computer-vision technologies are increasingly being used in applications as diverse as driving autonomous vehicles, medical diagnostics, damage assessment for insurance claims, and monitoring water levels and crop yield. 4. Liquid fuels from sunshine Can we mimic the humble leaf to create artificial photosynthesis to generate and store energy? The prospects are looking increasingly positive. The answer lies in using sunlight-activated catalysts to split water molecules into water and hydrogen, and then using the same hydrogen to convert CO2 into hydrocarbons. 5. The Human Cell Atlas An international collaboration aimed at deciphering the human body, called the Human Cell Atlas, was launched in October 2016. The project aims to identify every cell type in every tissue; learn exactly which genes, proteins, and other molecules are active in each type, and the processes which control that activity. 6. Precision farming The Fourth Industrial Revolution is providing farmers with a new set of tools to boost crop yield and quality while reducing water and chemical use. Sensors, robots, GPS, mapping tools, and data-analytics software are all being used to customize the care that plants need. 7. Affordable catalysts for green vehicles Progress is being made on a promising zero-emission technology, the hydrogen-fed fuel cell. Progress to date has been stymied by the high price of catalysts which contain platinum. However, much progress has been made in reducing reliance on this rare and expensive metal, and the latest developments involve catalysts that include no platinum, or in some cases no metal at all. 8. Genomic vaccines Vaccines based on genes are superior to more conventional ones in a number of ways. They are faster to manufacture, which is crucial during violent outbreaks. Compared to manufacturing proteins in cell cultures or eggs, producing genetic material should also be simpler and less expensive. 9. Sustainable design of communities Applying green construction to multiple buildings at once has the potential to revolutionize the amount of energy and water we consume. Sending locally-generated solar power to a smart microgrid could reduce electricity consumption by half and reduce carbon emissions to zero if a project currently under development at the University of California at Berkeley goes according to plan. 10. Quantum computing Quantum computers’ almost limitless potential has only ever been matched by the difficulty and cost of their construction. This explains why today the small ones that have been built have not yet managed to exceed the power of supercomputers. But progress is being made and in 2016 the technology firm IBM provided public access to the first quantum computer in the cloud.
2017.06.28
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Why Don't My Document Photos Rotate Correctly?
John, an insurance planner, took several photos of a competitors’ new brochures. At a meeting, he opened a photo gallery to discuss the documents with his colleagues. He found, however, that the photos of the document had the wrong orientation; they had been rotated in 90 degrees clockwise. He then rotated his phone 90 degrees counterclockwise, but the document photos also rotated at the same time. After trying this several times, he realized that it was impossible to display the document photos correctly on his phone. Instead, he had to set his phone down on a table and move his chair to show the photos in the correct orientation. It was very frustrating for John and his colleagues, because the document photos had different patterns of orientation errors. Professor Uichin Lee and his team at KAIST have identified the key reasons for such orientation errors and proposed novel techniques to solve this problem efficiently. Interestingly, it was due to a software glitch in screen rotation–tracking algorithms, and all smartphones on the market suffer from this error. When taking a photo of a document, your smartphone generally becomes parallel to the flat surface, as shown in the figure above (right). Professor Lee said, “Your phone fails to track the orientation if you make any rotation changes at that moment.” This is because software engineers designed the rotation tracking software in conventional smartphones with the following assumption: people hold their phones vertically either in portrait or landscape orientations. Orientation tracking can be done by simply measuring the gravity direction using an acceleration sensor in the phone (for example, whether gravity falls into the portrait or landscape direction). Professor Lee’s team conducted a controlled experiment to discover how often orientation errors happen in document-capturing tasks. Surprisingly, their results showed that landscape document photos had error rates of 93%. Smartphones’ camera apps display the current orientation using a camera-shaped icon, but users are unaware of this feature, nor do they notice its state when they take document photos. This is why we often encounter rotation errors in our daily lives, with no idea of why the errors are occurring. The team developed a technique that can correct a phone’s orientation by tracking the rotation sensor in a phone. When people take document photos their smartphones become parallel to the documents on a flat surface. This intention of photographing documents can be easily recognizable because gravity falls onto the phone’s surface. The current orientation can be tracked by monitoring the occurrence of significant rotation. In addition, the research team discovered that when taking a document photo, the user tends to tilt the phone, just slightly, towards the user (called a “micro-tilt phenomenon”). While the tilting degree is very small—almost indistinguishable to the naked eye—these distinct behavioral cues are enough to train machine-learning models that can easily learn the patterns of gravity distributions across the phone. The team’s experimental results showed that their algorithms can accurately track phone orientation in document-capturing tasks at 93% accuracy. Their approaches can be readily integrated into both Google Android and Apple iPhones. The key benefits of their proposals are that the correction software works only when the intent of photographing documents is detected, and that it can seamlessly work with existing orientation tracking methods without conflict. The research team even suggested a novel user interface for photographing documents. Just like with photocopiers, the capture interface overlays a document shape onto a viewfinder so that the user can easily double-check possible orientation errors. Professor Lee said, “Photographing documents is part of our daily activities, but orientation errors are so prevalent that many users have difficulties in viewing their documents on their phones without even knowing why such errors happen.” He added, “We can easily detect users’ intentions to photograph a document and automatically correct orientation changes. Our techniques not only eliminate any inconvenience with orientation errors, but also enable a range of novel applications specifically designed for document capturing.” This work, supported by the Korean Government (MSIP), was published online in the International Journal of Human-Computer Studies in March 2017. In addition, their US patent application was granted in March 2017. (Photo caption: The team of Professor Lee and his Ph.D.student Jeungmin Oh developed a technique that can correct a phone’s orientation by tracking the rotation sensor in a phone.)
2017.06.27
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Face Recognition System 'K-Eye' Presented by KAIST
Artificial intelligence (AI) is one of the key emerging technologies. Global IT companies are competitively launching the newest technologies and competition is heating up more than ever. However, most AI technologies focus on software and their operating speeds are low, making them a poor fit for mobile devices. Therefore, many big companies are investing to develop semiconductor chips for running AI programs with low power requirements but at high speeds. A research team led by Professor Hoi-Jun Yoo of the Department of Electrical Engineering has developed a semiconductor chip, CNNP (CNN Processor), that runs AI algorithms with ultra-low power, and K-Eye, a face recognition system using CNNP. The system was made in collaboration with a start-up company, UX Factory Co. The K-Eye series consists of two types: a wearable type and a dongle type. The wearable type device can be used with a smartphone via Bluetooth, and it can operate for more than 24 hours with its internal battery. Users hanging K-Eye around their necks can conveniently check information about people by using their smartphone or smart watch, which connects K-Eye and allows users to access a database via their smart devices. A smartphone with K-EyeQ, the dongle type device, can recognize and share information about users at any time. When recognizing that an authorized user is looking at its screen, the smartphone automatically turns on without a passcode, fingerprint, or iris authentication. Since it can distinguish whether an input face is coming from a saved photograph versus a real person, the smartphone cannot be tricked by the user’s photograph. The K-Eye series carries other distinct features. It can detect a face at first and then recognize it, and it is possible to maintain “Always-on” status with low power consumption of less than 1mW. To accomplish this, the research team proposed two key technologies: an image sensor with “Always-on” face detection and the CNNP face recognition chip. The first key technology, the “Always-on” image sensor, can determine if there is a face in its camera range. Then, it can capture frames and set the device to operate only when a face exists, reducing the standby power significantly. The face detection sensor combines analog and digital processing to reduce power consumption. With this approach, the analog processor, combined with the CMOS Image Sensor array, distinguishes the background area from the area likely to include a face, and the digital processor then detects the face only in the selected area. Hence, it becomes effective in terms of frame capture, face detection processing, and memory usage. The second key technology, CNNP, achieved incredibly low power consumption by optimizing a convolutional neural network (CNN) in the areas of circuitry, architecture, and algorithms. First, the on-chip memory integrated in CNNP is specially designed to enable data to be read in a vertical direction as well as in a horizontal direction. Second, it has immense computational power with 1024 multipliers and accumulators operating in parallel and is capable of directly transferring the temporal results to each other without accessing to the external memory or on-chip communication network. Third, convolution calculations with a two-dimensional filter in the CNN algorithm are approximated into two sequential calculations of one-dimensional filters to achieve higher speeds and lower power consumption. With these new technologies, CNNP achieved 97% high accuracy but consumed only 1/5000 power of the GPU. Face recognition can be performed with only 0.62mW of power consumption, and the chip can show higher performance than the GPU by using more power. These chips were developed by Kyeongryeol Bong, a Ph. D. student under Professor Yoo and presented at the International Solid-State Circuit Conference (ISSCC) held in San Francisco in February. CNNP, which has the lowest reported power consumption in the world, has achieved a great deal of attention and has led to the development of the present K-Eye series for face recognition. Professor Yoo said “AI - processors will lead the era of the Fourth Industrial Revolution. With the development of this AI chip, we expect Korea to take the lead in global AI technology.” The research team and UX Factory Co. are preparing to commercialize the K-Eye series by the end of this year. According to a market researcher IDC, the market scale of the AI industry will grow from $127 billion last year to $165 billion in this year. (Photo caption: Schematic diagram of K-Eye system)
2017.06.14
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Mutations Unveiled that Predispose Lung Cancer Cells to Refractory Histologic Transformation
Cancer pedigree analysis reveals the mutations in RB1 and TP53 genes play a key role in treatment-resistant, cancer cell-type transformation during EGFR inhibitor therapy for lung cancers. Research led by Korean medical scientists has discovered that a specific type of drug resistance mechanism to EGFR inhibitor therapy in lung cancer is predisposed by mutations in two canonical cancer-related genes: RB1 and TP53. Published in Journal of Clinical Oncology on May 12, the study also found those mutations can be detectable in patients' tumors at the point of clinical diagnosis. Therefore, it can be used as strong markers in clinic for predicting poor outcome for the targeted treatment for lung adenocarcinoma. Lung adenocarcinoma is the most common type of lung cancer, and about 15% of patients in Western countries and 50% of patients in Asian countries have mutations in the EGFR gene, which is critical for the development of lung cancer. Patients with lung adenocarcinoma harboring the EGFR mutation show favorable responses to EGFR inhibitors such as erlotinib (Tarceva) or gefitinib (Iressa), but ultimately relapse with drug-resistant tumors. Since the initial report in 2006, it has been known that in about 5~15% of patients, the lung adenocarcinoma cells undergo a mysterious transformation into a very different cancer cell type called “small cell lung cancer,” a much more aggressive lung cancer subtype, common in cigarette smokers. To find out the genetic basis of this process, the researchers compared the genome sequences of multiple cancer tissues acquired during the treatment courses of patients whose tumors underwent small-cell transformation. They reconstructed the cancer cell pedigree by comparing mutations between cancer tissues, and identified that RB1 and TP53 genes are completely inactivated by mutations already in their lung adenocarcinoma tissues. "We tried to compare the somatic mutational profile of pre-EGFR inhibitor treatment lung adenocarcinomas and post-treatment small cell carcinomas and to reconstruct the pedigrees of the cancer evolution in each patient. Strikingly, both copies of RB1 and TP53 genes were already inactivated at the stage of lung adenocarcinomas in all sequenced cases," said Dr. Jake June-Koo Lee, the first author from KAIST. They further pursued the clinical implications of RB1 and TP53 inactivation by investigating 75 EGFR-mutated lung adenocarcinoma tissues from patients who received EGFR inhibitor therapy, including patients with small-cell transformation. In this analysis, the lung adenocarcinomas with a complete inactivation of both RB1 and TP53 genes tended to have a 43-times greater risk of transformation into small cell lung cancer during their EGFR inhibitor treatment courses. Dr. Young Seok Ju, the co-last author from KAIST, explained, "This study shows the power of entire genome analyses to better understand the mechanisms underlying mysterious phenomenon encountered in clinic. Upon accurate bioinformatics, we are finding cancer-specific somatic mutations from the whole-genomes of patients’ cancer cells. These mutations allow us to track the evolution of cancer cells throughout the extraordinary clinical course of a special set of lung cancers." The complete inactivation of both RB1 and TP53 tumor suppressor genes is found in a minor (<10%) subset of lung adenocarcinoma. This study suggests that the clinical course against targeted therapy is endogenously different for the cancers in the subgroup, and specific drug-resistance mechanisms are predisposed by the two genetic mutations. Indeed, RB1 and TP53 double inactivation is a genetic hallmark of primary small cell lung cancer, observed in nearly all cases. "We are actively investigating patient tumor tissues to develop optimal surveillance plans and treatment options for patients with lung adenocarcinomas more prone to small-cell transformation," said Dr. Tae Min Kim, the co-last author from Seoul National University Hospital. The researchers are implementing their findings into lung cancer clinics by screening the RB1 and TP53 mutational status in lung adenocarcinoma patients receiving EGFR inhibitor treatment, and following their treatment courses to develop a treatment strategy for those patients. This research (doi.org/10.1200/JCO.2016.71.9096) was funded by the National Research Foundation of Korea (NRF-2013H1A2A1032691 to J.-K.L., NRF-2014R1A2A2A05003665 to Y.T.K.); Korea Institute of Science and Technology Information (K-16-L03-C02-S02 to J.L.); and the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, which was funded by the Ministry of Health and Welfare (HI14C1234 to T.M.K., HI16C2387 to Y.S.J.) Figure. Phylogeny analysis of serially-acquired tumors A. Phylogeny trees of sequenced cases (LC1−LC4) are reconstructed from the WGS data. Conceptual illustrations are depicted with grey color. Circles indicate major clones of the tumors. The length of each branch is proportional to the number of mutations that occurred in the branch. Mutations of cancer-related genes in each branch are indicated with arrows. The time points of relevant treatments are summarized below the trees. B. Mutations of RB1 and TP53 in two early LADCs (LC1b and LC4a) are visualized using Integrative Genomics Viewer (left panel). Allele-specific copy number analysis shows loss of heterozygosity of chromosomes 13 and 17 in both early LADCs and EGFR TKI-resistant SCLCs (right panel). C. Clonal evolution of LC1 is described with clinical history and tumor volumes. The horizontal axis represents the time from the diagnosis (0), and the vertical axis indicates the volume of tumors calculated from the computed tomography images. Abbreviations: LADC, lung adenocarcinoma; SCLC, small cell lung cancer
2017.06.07
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Bio-based p-Xylene Oxidation into Terephthalic Acid by Engineered E.coli
KAIST researchers have established an efficient biocatalytic system to produce terephthalic acid (TPA) from p-xylene (pX). It will allow this industrially important bulk chemical to be made available in a more environmentally-friendly manner. The research team developed metabolically engineered Escherichia coli (E.coli) to biologically transform pX into TPA, a chemical necessary in the manufacturing of polyethylene terephthalate (PET). This biocatalysis system represents a greener and more efficient alternative to the traditional chemical methods for TPA production. This research, headed by Distinguished Professor Sang Yup Lee, was published in Nature Communications on May 31. The research team utilized a metabolic engineering and synthetic biology approach to develop a recombinant microorganism that can oxidize pX into TPA using microbial fermentation. TPA is a globally important chemical commodity for manufacturing PET. It can be applied to manufacture plastic bottles, clothing fibers, films, and many other products. Currently, TPA is produced from pX oxidation through an industrially well-known chemical process (with a typical TPA yield of over 95 mol%), which shows, however, such drawbacks as intensive energy requirements at high temperatures and pressure, usage of heavy metal catalysts, and the unavoidable byproduct formation of 4-carboxybenzaldehyde. The research team designed and constructed a synthetic metabolic pathway by incorporating the upper xylene degradation pathway of Pseudomonas putida F1 and the lower p-toluene sulfonate pathway of Comamonas testosteroni T-2, which successfully produced TPA from pX in small-scale cultures, with the formation of p-toluate (pTA) as the major byproduct. The team further optimized the pathway gene expression levels by using a synthetic biology toolkit, which gave the final engineered E. coli strain showing increased TPA production and the complete elimination of the byproduct. Using this best-performing strain, the team designed an elegant two-phase (aqueous/organic) fermentation system for TPA production on a larger scale, where pX was supplied in the organic phase. Through a number of optimization steps, the team ultimately achieved production of 13.3 g TPA from 8.8 g pX, which represented an extraordinary yield of 97 mol%. The team has developed a microbial biotechnology application which is reportedly the first successful example of the bio-based production of TPA from pX by the microbial fermentation of engineered E. coli. This bio-based TPA technology presents several advantages such as ambient reaction temperature and pressure, no use of heavy metals or other toxic chemicals, the removable of byproduct formation, and it is 100% environmentally compatible. Professor Lee said, “We presented promising biotechnology for producing large amounts of the commodity chemical TPA, which is used for PET manufacturing, through metabolically engineered gut bacterium. Our research is meaningful in that it demonstrates the feasibility of the biotechnological production of bulk chemicals, and if reproducible when up-scaled, it will represent a breakthrough in hydrocarbon bioconversions.” Ph.D. candidate Zi Wei Luo is the first author of this research (DOI:10.1038/ncomms15689).The research was supported by the Intelligent Synthetic Biology Center through the Global Frontier Project (2011-0031963) of the Ministry of Science, ICT & Future Planning through the National Research Foundation of Korea. Figure: Biotransformation of pX into TPA by engineered E. coli. This schematic diagram shows the overall conceptualization of how metabolically engineered E. coli produced TPA from pX. The engineered E. coli was developed through reconstituting a synthetic metabolic pathway for pX conversion to TPA and optimized for increased TPA yield and byproduct elimination. Two-phase partitioning fermentation system was developed for demonstrating the feasibility of large-scale production of TPA from pX using the engineered E. coli strains, where pX was supplied in the organic phase and TPA was produced in the aqueous phase.
2017.06.05
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Observation of the Phase Transition of Liquid Crystal Defects
KAIST researchers observed the phase transition of topological defects formed by liquid crystal (LC) materials for the first time. The phase transition of topological defects, which was also the theme of the Nobel Prize for Physics in 2016, can be difficult to understand for a layperson but it needs to be studied to understand the mysteries of the universe or the underlying physics of skyrmions, which have intrinsic topological defects. If the galaxy is taken as an example in the universe, it is difficult to observe the topological defects because the system is too large to observe some changes over a limited period of time. In the case of defect structures formed by LC molecules, they are not only a suitable size to observe with an optical microscope, but also the time period in which the phase transition of a defect occurring can be directly observed over a few seconds, which can be extended to a few minutes. The defect structures formed by LC material have radial, circular, or spiral shapes centering on a singularity (defect core), like the singularity that was already introduced in the famous movie "Interstellar,” which is the center point of black hole. In general, LC materials are mainly used in liquid crystal displays (LCDs) and optical sensors because it is easy to control their specific orientation and they have fast response characteristics and huge anisotropic optical properties. It is advantageous in terms of the performance of LCDs that the defects of the LC materials are minimized. The research team led by Professor Dong Ki Yoon in the Graduate School of Nanoscience and Technology did not simply minimize such defects but actively tried to use the LC defects as building blocks to make micro- and nanostructures for the patterning applications. During these efforts, they found the way to directly study the phase transition of topological defects under in-situ conditions. Considering the LC material from the viewpoint of a device like a LCD, robustness is important. Therefore, the LC material is injected through the capillary phenomenon between a rigid two-glass plate and the orientation of the LCs can be followed by the surface anchoring condition of the glass substrate. However, in this conventional case, it is difficult to observe the phase transition of the LC defect due to this strong surface anchoring force induced by the solid substrate. In order to solve this problem, the research team designed a platform, in which the movement of the LC molecules was not restricted, by forming a thin film of LC material on water, which is like oil floating on water. For this, a droplet of LC material was dripped onto water and spread to form a thin film. The topological defects formed under this circumstance could show the thermal phase transition when the temperature was changed. In addition, this approach can trace back the morphology of the original defect structure from the sequential changes during the temperature changes, which can give hints to the study of the formation of topological defects in the cosmos or skyrmions. Prof. Yoon said, “The study of LC crystal defects itself has been extensively studied by physicists and mathematicians for about 100 years. However, this is the first time that we have observed the phase transition of LC defects directly.” He also added, "Korea is leading in the LCD industry, but our basic research on LCs is not at the world's research level." The first author of this study is Dr. Min-Jun Gimand supported by a grant from the National Research Foundation (NRF) and funded by the Korean Government (MSIP). The research result was published on May 30, 2017 in Nature Communications. Figure 1. The phase transition of the LC topological defect on cooling. Figure 2. Polarizing optical microscopy images of topological defects depending on the strength of the director field. (a,b,e) Convergent director field arrangements of LC molecules and corresponding schematic images; (c,d,f) Divergent director field arrangements of LC molecules and corresponding schematic images.
2017.06.02
View 9726
Augmented Reality Application for Smart Tour
‘K-Culture Time Machine,’ an augmented and virtual reality application will create a new way to take a tour. Prof. Woon-taek Woo's research team of Graduate School of Culture Technology of KAIST developed AR/VR application for smart tourism. The 'K-Culture Time Machine' application (iOS App Store app name: KCTM) was launched on iOS App Store in Korea on May 22 as a pilot service that is targetting the Changdeokgung Palace of Seoul. The application provides remote experience over time and space for cultural heritage or relics thorough wearable 360-degree video. Users can remotely experience cultural heritage sites with 360-degree video provided by installing a smartphone in a smartphone HMD device, and can search information on historical figures, places, and events related to cultural heritage. Also, 3D reconstruction of lost cultural heritage can be experienced. Without using wearable HMD devices, mobile-based cultural heritage guides can be provided based on the vision-based recognition on the cultural heritages. Through the embedded camera in smartphone, the application can identify the heritages and provide related information and contents of the hertages. For example, in Changdeokgung Palace, a user can move inside the Changdeokgung Palace from Donhwa-Gate (the main gate of the Changdeokgung Palace), Injeong-Jeon(main hall), Injeong-Moon (Main gate of Injeong-Jeon), and to Huijeongdang (rest place for the king). Through the 360 degree panoramic image or video, the user can experience the virtual scene of heritages. The virtual 3D reconstruction of the seungjeongwon (Royal Secretariat) which does not exist at present can be shown of the east side of the Injeong-Jeon The functions can be experienced on a smartphone without a wearable device, and it would be a commercial application that can be utilized in the field once the augmented reality function which is under development is completed. Professor Woo and his research team constructed and applied standardized metadata of cultural heritage database and AR/VR contents. Through this standardized metadata, unlike existing applications which are temporarily consumed after development, reusable and interoperable contents can be made.Professor Woo said, "By enhancing the interoperability and reusability of AR contents, we will be able to preoccupy new markets in the field of smart tourism." The research was conducted through the joint work with Post Media (CEO Hong Seung-mo) in the CT R&D project of the Ministry of Culture, Sports and Tourism of Korea. The results of the research will be announced through the HCI International 2017 conference in Canada this July. Figure 1. 360 degree panorama image / video function screen of 'K-Culture Time Machine'. Smartphone HMD allows users to freely experience various cultural sites remotely. Figure 2. 'K-Culture Time Machine' mobile augmented reality function screen. By analyzing the location of the user and the screen viewed through the camera, information related to the cultural heritage are provided to enhance the user experience. Figure 3. The concept of 360-degree panoramic video-based VR service of "K-Culture Time Machine", a wearable application supporting smart tour of the historical sites. Through the smartphone HMD, a user can remotely experience cultural heritage sites and 3D reconstruction of cultural heritage that does not currently exist.
2017.05.30
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Extreme Materials for Fusion with Metal Cocktail
The research team under Professor Ryu Ho-jin of the Department of Nuclear and Quantum Engineering has developed a new material for facing fusion plasma environments using metal powder mixing technology. This technology is expected to extend the range of materials that can be designed for use in extreme environments such as in fusion power generators. The durability of the tokamak vessel, which holds high-temperature plasma, is very important to create fusion power reactors, which are expected to be a future energy source. Currently, high-melting-point metals, such as tungsten, are considered plasma-facing materials to protect the tokamak vessel. However, high-energy thermal shocks, plasma ions, and neutrons are fatal to the plasma-facing material during high temperature fusion plasma operation. Therefore, it is necessary to develop new high-performance materials. The ITER project, in which seven countries including the United States, the EU, and Korea participate jointly, is constructing a nuclear fusion experimental reactor in France with the goal of achieving the first plasma in 2025 and deuterium-tritium fusion operation in 2035. In Korea, the KSTAR tokamak at the National Fusion Research Institute has succeeded in maintaining high-performance plasma for 70 seconds. Researchers in Europe, the United States, and China, who are leading the research on fusion plasma-facing materials, are studying the improvement of physical properties by adding a small amount of metal elements to tungsten. However, Professor Ryu’s team reported that by mixing various metals’ powders, including tungsten, they have succeeded in producing a new material that has twice the hardness and strength of tungsten. The difference in the atomic sizes of the well-mixed elements in the alloy is very significant because it makes it difficult to deform the alloy. The team will continue its research to find alloying compositions that optimize mechanical properties as well as thermal conductivity, plasma interactions, neutron irradiation embrittlement, tritium absorption, and high-temperature oxidation properties. Professor Ryu said, "Fusion plasma-facing materials are exposed to extreme environments and no metal is capable of withstanding thermal shock, plasma, and neutron damage simultaneously. As a result of this research, attempts to develop complex metallic materials for nuclear fusion and nuclear power are expected to become more active around the world. " Ph.D. candidate Owais Ahmed Waseem is the first author of this project. The research is supported by the Ministry of Science, ICT and Future Planning, the Korea Research Foundation's Fusion Basic Research project, and the Engineering Research Center. The results were published in 'Scientific Report' on May 16. Figure 1. Tungsten-based high strengh alloy sample Figure 2. Fusion plasma facing material development by powder processing of refractory elements
2017.05.26
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Controlling 3D Behavior of Biological Cells Using Laser Holographic Techniques
A research team led by Professor YongKeun Park of the Physics Department at KAIST has developed an optical manipulation technique that can freely control the position, orientation, and shape of microscopic samples having complex shapes. The study has been published online in Nature Communications on May 22. Conventional optical manipulation techniques called “optical tweezers,” have been used as an invaluable tool for exerting micro-scale force on microscopic particles and manipulating three-dimensional (3-D) positions of particles. Optical tweezers employ a tightly-focused laser whose beam diameter is smaller than one micrometer (1/100 of hair thickness), which can generate attractive force on neighboring microscopic particles moving toward the beam focus. Controlling the positions of the beam focus enabled researchers to hold the particles and move them freely to other locations so they coined the name “optical tweezers,” and have been widely used in various fields of physical and biological studies. So far, most experiments using optical tweezers have been conducted for trapping spherical particles because physical principles can easily predict optical forces and the responding motion of microspheres. For trapping objects having complicated shapes, however, conventional optical tweezers induce unstable motion of such particles, and controllable orientation of such objects is limited, which hinder controlling the 3-D motion of microscopic objects having complex shapes such as living cells. The research team has developed a new optical manipulation technique that can trap complex objects of arbitrary shapes. This technique first measures 3-D structures of an object in real time using a 3-D holographic microscope, which shares the same physical principle of X-Ray CT imaging. Based on the measured 3-D shape of the object, the researchers precisely calculates the shape of light that can stably control the object. When the shape of light is the same as the shape of the object, the energy of the object is minimized, which provides the stable trapping of the object having the complicated shape. Moreover, by controlling the shape of light to have various positions, directions, and shapes of objects, it is possible to freely control the 3-D motion of the object and make the object have a desired shape. This process resembles the generation of a mold for casting a statue having desired shape so the researchers coined the name of the present technique “tomographic mold for optical trapping (TOMOTRAP).” The team succeeded in trapping individual human red blood cells stably, rotating them with desired orientations, folding them in an L-shape, and assembling two red blood cells together to form a new structure. In addition, colon cancer cells having a complex structure could be stably trapped and rotated at desired orientations. All of which have been difficult to be realized by the conventional optical techniques. Professor Park said, “Our technique has the advantage of controlling the 3-D motion of complex shaped objects without knowing prior information about their shape and optical characteristics, and can be applied in various fields including physics, optics, nanotechnology, and medical science.” Dr. Kyoohyun Kim, the lead author of this paper, noted that this technique can induce controlled deformation of biological cells with desired shapes. “This approach can be also applied to real-time monitoring of surgical prognosis of cellular-level surgeries for capturing and deforming cells as well as subcellular organelles,” added Kim. Figure 1. Concept of optical manipulation techniques Figure 2. Experimental setup Figure 3. Research results
2017.05.25
View 8549
Total Synthesis of Flueggenine C via an Accelerated Intermolecular Rauhut-Currier Reaction
The first total synthesis of dimeric securinega alkaloid (-)-flueggenine C was completed via an accelerated intermolecular Rauhut–Currier (RC) reaction. The research team led by Professor Sunkyu Han in the Department of Chemistry succeeded in synthesizing the natural product by reinventing the conventional RC reaction. The total synthesis of natural products refers to the process of synthesizing secondary metabolites isolated from living organisms in the laboratory through a series of chemical reactions. Each stage of chemical reaction needs to be successful to produce the final target molecule, and thus the process requires high levels of patience and creativity. For that reason, the researchers working on natural products total synthesis are often called “molecular artists”. Despite numerous reports on the total synthesis of monomeric securinegas, the synthesis of dimeric securinegas, whose monomeric units are connected by a putative enzymatic RC reaction, has not been reported to date. The team used a Rauhut-Currier (RC) reaction, a carboncarbon bond forming a reaction between two Michael acceptors first reported by Rauhut and Currier in 1963, to successfully synthesize a dimeric natural product, flueggenine C. This new work featured the first application of an intermolecular RC reaction in total synthesis. The conventional intermolecular RC reaction was driven non-selectively by a toxic nucleophilic catalyst at a high temperature of over 150°C and a highly concentrated reaction mixture, and thus has never been applied to natural products total synthesis. To overcome this long-standing problem, the research team placed a nucleophilic moiety at the γ-position of the enone derivative. As a result, the RC reaction could be induced by the simple addition of a base at ambient temperature and dilute solution, without the need of a nucleophilic catalyst. Using this newly discovered reactivity, the team successfully synthesized the natural product (-)-flueggenine C from commercially available amino acid derivative in 12 steps. Professor Han said, “Our key finding regarding the remarkably improved reactivity and selectivity of the intermolecular RC reaction will serve as a significant stepping stone in allowing this reaction to be considered a practical and reliable chemical tool with broad applicability in natural products, pharmaceuticals, and materials syntheses. ” This research was led by Ph.D. candidate Sangbin Jeon and was published in The Journal of the American Chemical Society (JACS) on May 10. This research was funded by KAIST start-up funds, HRHR (High-Risk High-Return), RED&B (Research, Education, Development & Business) projects, the National Research Foundation of Korea, and the Institute for Basic Science. (Figure 1: Representative dimeric/oligomeric securinega alkaloids) (Figure 2: Our reinvented Rauhut-Currier reaction) (Figure 3: Total Synthesis of (-)-flueggenine C)
2017.05.23
View 9313
Parasitic Robot System for Turtle's Waypoint Navigation
A KAIST research team presented a hybrid animal-robot interaction called “the parasitic robot system,” that imitates the nature relationship between parasites and host. The research team led by Professor Phil-Seung Lee of the Department of Mechanical Engineering took an animal’s locomotive abilities to apply the theory of using a robot as a parasite. The robot is attached to its host animal in a way similar to an actual parasite, and it interacts with the host through particular devices and algorithms. Even with remarkable technology advancements, robots that operate in complex and harsh environments still have some serious limitations in moving and recharging. However, millions of years of evolution have led to there being many real animals capable of excellent locomotion and survive in actual natural environment. Certain kinds of real parasites can manipulate the behavior of the host to increase the probability of its own reproduction. Similarly, in the proposed concept of a “parasitic robot,” a specific behavior is induced by the parasitic robot in its host to benefit the robot. The team chose a turtle as their first host animal and designed a parasitic robot that can perform “stimulus-response training.” The parasitic robot, which is attached to the turtle, can induce the turtle’s object-tracking behavior through repeated training sessions. The robot then simply guides it using LEDs and feeds it snacks as a reward for going in the right direction through a programmed algorithm. After training sessions lasting five weeks, the parasitic robot can successfully control the direction of movement of the host turtles in the waypoint navigation task in a water tank. This hybrid animal–robot interaction system could provide an alternative solution of the limitations of conventional mobile robot systems in various fields. Ph.D. candidate Dae-Gun Kim, the first author of this research said that there are a wide variety of animals including mice, birds, and fish that could perform equally as well at such tasks. He said that in the future, this system will be applied to various exploration and reconnaissance missions that humans and robots find it difficult to do on their own. Kim said, “This hybrid animal-robot interaction system could provide an alternative solution to the limitations of conventional mobile robot systems in various fields, and could also act as a useful interaction system for the behavioral sciences.” The research was published in the Journal of Bionic Engineering April issue.
2017.05.19
View 9955
Study Identifies the Novel Molecular Signal for Triggering Septic Shock
Professor Seyun Kim’s team at the Department of Biological Sciences reported the mechanism by which cellular signaling transduction networks are precisely controlled in mediating innate immune responses, such as sepsis, by the enzyme IPMK (Inositol polyphosphate multikinase) which is essential for inositol biosynthesis metabolism. In collaboration with Professor Hyun Seong Roh at Seoul National University, the study’s first author, Eunha Kim, a Ph.D. candidate in Department of Biological Sciences, performed a series of cellular, biochemical, and physiological experiments searching for the new function of IPMK enzymes in macrophages. The research findings were published in Science Advances on April 21. Professor Kim’s team has been investigating various inositol metabolites and their biosynthesis metabolism for several years and has multilaterally identified the signaling actions of IPMK for controlling cellular growth and energy homeostasis. This research showed that the specific deletion of IPMK enzymes in macrophages could significantly reduce levels of inflammation and increase survival rates in mice when they were challenged by microbial septic shock and endotoxins. This suggests a role for IPMK enzymes in mediating innate inflammatory responses that are directly related to a host’s defense against pathogenic bacterial infection. The team further discovered that IPMK enzymes directly bind to TRAF6 proteins, a key player in immune signaling, thus protecting TRAF6 proteins from ubiquitination reactions that are involved in protein degradation. In addition, Kim and his colleagues successfully verified this IPMK-dependent immune control by employing short peptides which can specifically interfere with the binding between IPMK enzymes and TRAF6 proteins in macrophage cells. This research revealed a novel function of IPMK enzymes in the fine tuning of innate immune signaling networks, suggesting a new direction for developing therapeutics targeting serious medical conditions such as neuroinflammation, type 2 diabetes, as well as polymicrobial sepsis that are developed from uncontrolled host immune responses. This research was funded by the Ministry of Science, ICT and Future Planning. (Figure: Deletion of IPMK (inositol polyphosphate multikinase) in macrophages reduces the stability of TRAF6 protein which is the key to innate immune signaling, thereby blocking excessive inflammation in response to pathological bacterial infection.)
2017.05.11
View 9003
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