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2017-01 09

[Academics]Treating Aftereffects of Brain-Related Diseases

Professor Koh Seong-ho of the Department of Neurology is a doctor and a researcher who is interested in treating the aftereffects of Alzheimer's disease and cerebral infarction. He received his doctorate degree from Hanyang University and used to work at Harvard University as a research fellow. Koh is general affairs manager of the Korean Dementia Association, and associate managing editor of the Journal of Clinical Neurology. His recent paper, “Neuroprotective Effects of Acetyl-L-Carnitine Against Oxygen-Glucose Deprivation-Induced Neural Stem Cell Death”, focuses on acetyl-L-carnitine’s function of protecting and enhancing the regeneration of neural stem cells. Koh explains the neuroprotective function of acetyl-L-carnitine. Acetyl-L-carnitine, or ALCAR for short, is a source of energy. It is an ingredient for mitochondria inside stem cells as well as other cells. When cerebral infarction occurs, which is when arteries in the brain get clogged, oxygen and glucose become deprived as blood circulation is blocked. In this situation, when oxygen glucose deprivation (OGD) occurs, mitochondria receive damage as well. The coenzyme inside the mitochondria, which makes energy for the stem cells, is pushed out, resulting in cell death. There are three well-known types of cell death, which are necrosis, apoptosis, and autophagy. Koh’s research is focused on apoptosis where cell death occurs gradually, unlike necrosis. ALCAR can assist apoptosis in preserving and reviving the cells. Koh conducted an experiment using neural stem cells extracted from rats, and exposed the cells to an OGD environment similar to cerebral infarction. By increasing the concentration levels of ALCAR to that of stem cells that died of OGD, Koh found that they could be revived owing to ALCAR. “What we found out from our study is that ALCAR is not only a supporting material for mitochondria’s metabolism, but it also protects and regenerates stem cells,” Koh said. Neural stem cells of rats. Nestin, Ki67, and DAPI are markers that show that these are neural stem cells. (Photo coutesy of Koh) “When a cell dies, free oxygen radicals are created. Free oxygen radicals can be emerged as a response to stress caused by diseases. Too much free oxygen radicals may stop proteins from functioning, induce inflammation, cause even more cell death and increase pathogens,“ described Koh. ALCAR can help reserve some cells to proliferate when cell death occurs. This can be done by passing on energy, and reducing free oxygen radicals and oxidative stress caused by the radicals. “Through the research, we found out that in an OGD environment where the survival rate of the cell was only 40%, the cells regenerated up to 80% with ALCAR- twice as much,” Koh explained. The bar graph shows the cell survival rate and the line graph shows the cell death rate. The black bar shows an OGD state where ALCAR does not exist. From this graph, we can clearly see that ALCAR revives the dead cells. (Photo courtesy of Koh) The distinct contrast between cell population (purple dots) and the second and third petri dishes shows ALCAR'S capacity for regenerating cells. The graph below it shows the population of cells before and after ALCAR exposure. (Photos courtesy of Koh) “What we discovered is ALCAR’s function of manipulating survival-related proteins and death-related proteins, which reduces apoptosis,” Koh reiterated. Cells are immensely complicated systems, and one of those receive various signals sent by proteins with regard to their types and locations in the human body. The study concentrated on the signals that PI3K (phosphoinositide 3-kinase) send which are significant to the survival, proliferation, and differentiation of cells. ALCAR activates PI3K, thereby controlling the survival and death of related proteins. “We examined protein levels and then used a blocker that obstruct the signal path of PI3K. We could see that the effects of ALCAR was impeded as well due to the blockage, proving that ALCAR is associated with PI3K and its pathway,” Koh elaborated. "Bad results could turn out to be a trigger for another good research." According to Koh, there isn't much treatment for the aftereffects of brain-related diseases such as cerebral infarction and Alzheimer’s disease, even though a lot of patients suffer from them. However, if Koh’s research continues and neural stem cells can be conserved and recovered, those aftereffects could see improvement. Currently there are many projects in line with his study, funded by Korea's Ministry of Science, ICT and Future Planning and the Ministry of Health and Welfare. Koh is also participating in a joint study with Harvard University, which centers on the connection and networks between cells and neural cells in a pathologic condition, and whether that would lead to a recovery or not. “When doing research, it is nice to get the results you desire, but this isn’t easy in most cases. I try to think positively though, because I believe that even bad results could turn out to be a trigger for another good research,” remarked Koh with a smile. The ultimate goal of Koh’s study is developing treatment for patients who are already diagnosed with brain-related diseases, by studying the proliferation and regeneration of neural stem cells. Koh added that he is also interested in researching how to enhance patients' memory and their cognitive functions. “It's regrettably sad how lot of research has been done, but there is no specific treatment for neural diseases. As a doctor responsible for curing patients, I want to try my best to help them by improving their conditions through my research, also contributing to the development of science as I go,” said Koh. Koh continues to seek methods to enhance patients' conditions who are already diagnosed with cerebral infarction and Alzheimer's disease. Jang Soo-hyun luxkari@hanyang.ac.kr Photos by Moon Ha-na

2017-01 02

[Academics][Researcher of the Month] Scientific Integration Approach to Programmable Nuclease (1)

When a baby is identified to have been born with a rare, incurable disease, it would bring about concerns and sorrow to the newborn and the parents. However, with the prospective research on CRISPR Cas-9 system, or a programmable nuclease, a host of diseases will prevented without further ado. Professor Bae Sang-su of the Department of Chemistry explains the mechanism of the CRISPR Cas-9 system through his research “Structural roles of guide RNAs in the nuclease activity of Cas-9 endonuclease”. Also, he reveals the course of his life towards scientific integration that shapes the bright future of scientific studies. Structural properties and significance of CRISPR Cas-9 The significance of this research paper is that it explains the structural mechanisms of the CRISPR Cas-9 system and how it can modify or edit DNAs in cells. CRISPR-Cas 9 stands for Clustered Regularly Interspaced Short Palindromic Repeats, which relies on a protein named Cas-9. As it is called by the name of 'molecule scissors', it introduces the new spectrum of genome editing technology. Even though there already have been two programmable nuclease systems which are the Zinc Finger Nuclease and the TALENs(Transcriptor Activator Like Effector Nuclease System). The former is the first generation of the genome editing system that is compiled of one zinc finger and three to four nucleases. The title originated from the chemical component zinc, because this DNA contained certain amount of zinc. Then the second generation of genome editing system developed, which was called the TALENs that contained the base named xanthomonas originating from vegetable pathogens. “These two generations were startling contributions to scientific development, but with the advent of the third generation of genome editing, the CRISPR Cas-9 system, the scientific world could not contain its surprise,” said Bae. The CRISPR Cas-9 system was simpler in application to various circumstances and in the modification of DNAs. The significance of the CRISPR Cas-9 system is that it can enhance the welfare of human life in various aspects. “This technology is currently being applied to plants and animals, and also is in process of availing itself to humans by amending laws. Application of the system to humans will take 10 years at the most, since the research is developing at a fast pace,” explained Bae. An example of genome-modified plant through the CRISPR Cas-9 system that Bae provided was a modified mushroom in the United States. Discoloration of mushrooms by time lapse was prevented due to the CRISPR Cas-9 system, and the mushroom could maintain its original color for a long time. Bae explained that “not only does the CRISPR Cas-9 system treat incurable diseases of humans, but it can also modify DNAs in plants and animals to increase marketability.” Bae is explaining the significance of the CRISPR Cas-9 system. However, the genome editing system has been controversial in the scientific academia due to its resemblance to genetically modified organisms, also called GMO. According to Bae, there is a blunt difference between the two because GMO requires DNAs extracted from other organisms to modify the sample, while the CRISPR Cas-9 system modifies DNAs in the sample itself. “Even though some experts call the CRISPR Cas-9 system a part of GMO, the American Food and Drug Administration has acknowledged the genome editing program as a discrete system,” said Bae. Another controversy that the CRISPR Cas-9 system is incurring is the occurrence risk of a tailored baby. Even though there is a low possibility in creation of so called 'monsters', the prospect of the system is inexhaustible that the scientific academia can’t forecast the future application of the CRISPR Cas-9 system. “The application of the system should be discreetly considered and contemplated, in order to prevent any accounts of abuse incurred by a little crack of regulations,” said Bae. Scientific integration approach and its synergy effects One of the reasons why Bae could successfully reveal the mechanism of this newly found technology was due to his academic background. Bae got his bachelor’s, master’s, and doctoral degrees in physics, while pursuing chemical studies in his post-doctoral program. Once he became a professor in the chemistry department, he encountered the Method of the Year- 2013 published by Nature Method, which was introducing the new technology, the CRISPR Cas-9 system. As Bae was carried away by the astonishment, he got involved in the genome engineering research in earnest. “Although there could be some drawbacks for me to research biological technology because I majored in physics and chemistry, I thought that I can sublimate these flaws into advantages through scientific integration,” said Bae. Because he majored in physics, he could access the research in a physician’s perspective of ‘how and why’, instead of a biologist’s perspective of ‘so.’ According to Bae, he demonstrated his full potential and capabilities in this research as both physician and chemist, because he could inquire the structural mechanisms of the system and create programs using various physical means like razors. In his teenage years, Bae was interested in studying science since he was a student of natural sciences and engineering. Moment by moment, Bae immersed himself in scientific research, and in his graduate school years, he spent great energy and time researching for scientific development. Due to his diverse academic background, Bae could successfully pursue his amalgamative research in different scientific fields. Now, another approach to scientific integration is in progress, as the CRISPR Cas-9 system is being applied to different fields. “As a scientist researching the CRISPR Cas-9 system, I have to cooperate with experts from profoundly dissimilar fields. Lack of knowledge between each others’ academic branches and hardship in communication may bring about discord. Thus, efforts to understand and study each others’ academic knowledge through cooperation is the key to successful results,” said Bae. A scientific integration approach has been the key to successful research on the CRISPR Cas-9 system. Bae's ultimate goal is to apply this original research of CRISPR Cas-9 system to different fields through joint research. To the question of how he will encourage and foster junior scholars at Hanyang University, he answered with ‘confidence.’ “I have studied and researched at various universities with different experts, and I have realized that students of Hanyang University are equally capable to these scientists. With confidence and courage to carry on their majors with tenacity, students of Hanyang University can demonstrate their capabilities to the fullest,” said Bae. Kim Ju-hyun kimster9421@hanyang.ac.kr Photos by Kim Youn-soo

2016-12 27 Important News

[Academics]Semi-Conductors for Convenience

Professor Park Jea-gun of the Department of Electronic Engineering is an expert in the field of semi-conductors, having researched it for 31 years now. His paper, “Effect of double MgO tunneling barrier on thermal stability and TMR ratio for perpendicular MTJ spin-valve with tungsten layers“, discusses the magnetic memory, which is a totally different type of memory device in the current market other than the DRAM (dynamic random-access memory) and the NAND (negative-AND) flash memory. As semi-conductors are made into smaller models, it becomes faster as the electric power it needs gets lower, and the cost to produce the model gets lower as well. In the world of IT, the reading and writing of information should get faster as time goes. But since there are limits to the current technology in reducing the size of the semi-conductors smaller than 10 nanometers, there have been attempts to make a different type of model that could replace the DRAM technology. Park explains about the magnetic memory being developed at HYU. Tohoku University (THU) in Japan came up with the idea of magnetic memory from which Hanyang University (HYU), along with Samsung Electronics, SK Hynix, and the Korean government invested 40 billion won to develop a semi-conductor research facility. There are only two other facilities that are able to produce such novel technology, which are in the United States and Belgium. Since the idea provided by THU was not a fully developed one, Park changed the material needed to produce it into tungsten. The result has been quite successful in that it can now be activated even at 400 degrees while what was proposed at THU could only hold up to 300 degrees. The original memory types used to have what is called a capacitor. By charging electrons in it or discharging it, the digital signal becomes 1 and 0 respectively. As for the magnetic memory, it has two magnetic layers. One has fixed electron while the other has a free one. In between the two layers, there is an insulation layer. The fixed electron always flows in the same direction while the free electron flows in the direction of the electric power. Once the two electrons are flowing in the same direction, more electric power flows and it has lower resistance, which reads data 0 state while the opposite means data 1. In other words, it can be said that the way to produce D0 and D1 is different from the original type in charging the electrons and discharging them, or by letting the electrons flow in either the same or opposite direction. The sizes of DRAM and NAND would be difficult to get smaller than 10 nm. (Photo courtesy of Park) Evidently, there are advantages to the magnetic memory in that the changes in the direction of flow of electrons are very fast. Charging and discharging capacitors take much longer and consumes more electric power as well. In addition, the capacitor needs a certain surface area, while this new form of memory gets faster as the size gets smaller. It can be said that this nano structure element is an absolute must when it comes to scaling down the size of memory storage. It is believed that this technology would be necessary in developing the internet of things, or IOT technology, once it has been stabilized. Magnetic memory has now been successfully installed onto a System on Chip (SoC). This technology is crucial for IOT technology, and it is predicted that the memory technology at this stage will not be in use by 2022 to 2025. Park wishes that his technology would make people's lives more easier. Park believes that by developing the original technology and being credited for the paper would eventually be a huge contribution to the Korean society where the semi-conductor industry accounts for about 5% of Korean GDP. Through his technology, Park aims to make people feel the comfort of advanced technology when it comes to our daily lives and the information-oriented era. Kim Seung-jun nzdave94@hanyang.ac.kr Photo by Kim Youn-soo

2016-12 18 Important News

[Academics]Improving the Bioavailability of Fruit Wastes

Professor Jeon Byong-hun of the Department of Earth Resources and Environmental Engineering has been studying and experimenting with the objective of increasing the bioavailability of food wastes through the process of biomass pretreatment, which is a part of the process of biofuel production. Specifically centralizing on the energy recovery of fruit peels and wastes, Jeon has successfully managed to increase the rate in which he derived the energy recovery from micro-algae to 46%. Considering that the record of deriving energy recovery from any types of biomass was 41%, he regards this result as a significant progress in increasing the bioavailability of biomass. Biomass and pretreatment Humans can take in food freely and absorb the nutrients through digestion, but microorganisms have a different means of doing so. Microorganisms must utilize organic matters and generate energy from them, which corresponds to the process of producing biofuel. In an aqueous solution, microorganisms make contact with organic matters and drag them inwards, meaning that the finer and more dispersed the organic matters are, the easier and more efficient a microorganism can derive energy from them. This gives rise to the concept of bioavailability, which plays an influential role in determining how much biofuel can be converted from organic matter to energy recovery. In other words, the form in which the organic matter is structured determines the bioavailability. In this context, the pretreatment of biomass can be a decisive step. Jeon explains that pretreatment of biomass plays a significant role. The form previously mentioned does not only come in the size of the organic matter but also in the type of the biomass. The three big categories of usable biomass are carbohydrates, lipids, and proteins. “Consider this example. When trying to formulate alcohol, which comes from carbohydrates, it would be optimal if the carbohydrate is uncombined with any other biomasses. If it is, then the microorganism will have less convenience in deriving energy from it- thus, decreasing bioavailability. It is only when the biomass is in the desired form that the microorganism will convert the most energy from the organic matter,” explained Jeon. Jeon and his laboratory researchers have been ultimately seeking to turn a variety of different biomass into various forms of bioenergy. “Making use of biomass such as fruit wastes, micro-algae, and food rubbish to extract the maximum amount of bioenergy in forms of bio-gas, bio-alcohol, and biodiesel has been our goal,” remarked Jeon. In a broader sense, his research includes turning the three big categories of biomass—carbohydrates, lipids, and proteins—into the most productive and accessible bioenergy. Jeon hopes to increase the bioavailability of biomass and convert them into sustainable, eco-friendly energy. Bioenergy and its advantages Jeon also shed light on the flexible versatility of bioenergy, putting emphasis on its convenience and portability. Unlike other forms of energy such as solar power, wind power or electricity, bioenergy is portable and storable. In the case of solar or wind power, the energy must be converted into forms of electricity and be put in a battery for storage and transportation. Electricity always necessitates cables, wires, and power transmission systems, whereas bioenergy is free from all these requirements. On the same note, petroleum, gas, and diesel could also be the most convenient forms of energy—satisfying both portability and storability—which is why it is being used worldwide. Nonetheless, the reason Jeon still argues for bioenergy is because of its eco-friendly aspect. “Research and development of bioenergy is an indispensable task for humans. Our perpetual goal is to devise the method of producing bioenergy with stability, drawing the most from the limited, given biomass. We must find a way to obtain bioenergy with sustainability, converting carbohydrates, lipids, and proteins into sustainable biofuels,” concluded Jeon. Microalgae being converted into biofuel in storable form. Jeon Chae-yun chaeyun111@hanyang.ac.kr Photos by Moon Ha-na

2016-12 11 Important News

[Academics]Structural Roles of gRNAs in the CRISPR-Cas9 System

Professor Bae Sang-su of Department of Chemistry is an expert in the field of CRISPR-Cas9 system, which recognizes target DNA with the help of two gRNAs (Guide RNA): tracrRNA (trans-activating CRISPR RNA) and crRNA (CRISPR RNA). DNA (deoxyribonucleic acid) is the carrier of genetic information which is the main constituent of chromosomes, and RNA (ribonucleic acid) is a messenger that carries instructions from DNA for controlling the synthesis of protein. CRISPR-Cas9 stands for Clustered Regularly Interspaced Short Palindromic Repeats, which relies on the protein named Cas9. Also known by the name of 'molecule scissors' that introduces mutations and changes into DNAs, Bae reveals the mechanism of the CRISPR-Cas9 system through his research paper, "Structural roles of guide RNAs in the nuclease activity of Cas9 endonuclease". Mechanism of the CRISPR-Cas9 system All living things are composed of cells and in them exist DNAs. Thus, if the mechanism of DNAs is feasible to be identified in every sequence, modifications or alternations in mutation become possible. Along with the development of artificial intelligence studies, research on the CRISPR-Cas9 system has recently been nominated as the momentous scientific work of the year by Nature Method, the most authoritative magazine in the chemical field. “This paper reveals the mechanism of how the CRISPR-Cas9 system can detect and modify the faulty areas of a given DNA. The process can be described as a surgical operation which should be performed precisely, since the surgeon has to accurately whittle down morbid parts of organs,” said Bae. Bae also remarked on the importance of research in the single molecule level. According to Bae, in order to utilize and apply the CRISPR-Cas9 system into remedying rare hereditary diseases or creating novel organisms, intricate research and experimentation in the rudimentary levels are crucial. “The process of experimentation took a little more than two years, until this research thesis was produced. I majored in physics, obtained a doctorate degree in chemistry, and this research I am currently working on biology. Convergence in science is needed because the biological application of the research mandates physical methodology and chemical materials,” said Bae. He also accounted for the process minutely that the physical methodology he employed was using razors to inquire into the fundamental states of the CRISPR DNA acting as molecule scissors to amputate the accurate parts of DNA. CRISPR-Cas9 cleavage activity with various mutated targets of DNA. (Photo courtesy of Nature) Legal regulation demands on research Although the research of CRISPR DNA embarked in 2013, the three-year study developed rapidly, that the legal regulations regarding the employment of CRISPR technology are not yet procured. “Now is the time to amend the laws considering the development of CRISPR research and bioethics. Regarding the current pace of research, application of the CRISPR DNA would take effect in 10 years, and if properly used, this technology is practicable to save a host of people, and also improve the quality of life,” added Bae. Referring to Bae, this field of science will change the world, in that the CRISPR molecule scissors can bring out alternations in humans, animals, plants, and even viruses. “The advent of DNA modification in all living things is becoming feasible. In the movie ‘Gattaca,’ the future world discriminates humans born naturally with recessive genes, as the ones with modified genes are considered dominant. As so, concerns regarding negative employments of CRISPR DNA are prevalent, and this adjures the judicial amendments to delicately take account for this technology,” said Bae. There are numerous advantages this technology accompanies: remedying hereditary diseases, protecting endangered animals, and plants, and more. Thus, in order to properly apply the technology to real life, the government should arrange for regulations rightfully, unlike the employment of nuclear power that entailed tragic courses. Professor Bae Sang-su emphasizes the significance of law amendments regarding the CRISPR-Cas9 technology. Promising developments Despite the short time span of research, in the course of three years, the South Korean research team is in the lead in CRISPR experiments and applications, along with the top five groups of the world, including Harvard, MIT, UC Berkeley and more. “The ultimate goal of my research team is to create ingenious and distinctive technology that is distinguished from other countries’ research teams,” said Bae. According to him, the South Korean research team is ahead of others in areas of CRISPR DNA investigation and application. In 2017, rice rectified through CRISPR modification will be made public, along with CRISPR DNA-rectified pigs. This will incite further developments in remedying diseases like cancer and other incurable diseases. In order to increase the spectrum of research applications, the South Korean government and experts from the fields of law and science are gathering to amend laws. There are advancements in the judicial and scientific joint consultations that will be initiated on December 21st, 2016, by the Korean Genome Editing Society. Kim Ju-hyun kimster9421@hanyang.ac.kr Photo by Moon Ha-na

2016-12 05

[Academics]Earthquake Spectra and Sound Structures

Professor Han Sang-whan of Department of Architectural Engineering is an expert in the field of earthquake and structural engineering. “More recently from the earthquake that hit Gyeongju on September 12th this year, there is an increasing awareness regarding the safety of buildings,” said Han. Thus, he has been researching on improving the standards of buildings before and after it is constructed. His recent papers, “Effect of connection rotation capacities on seismic performance of IMF systems” and “Building Height Limits for Steel Intermediate Moment Frames” specifically shed light on enduring an earthquake's seismic power. Accurate prediction of seismic loading and production There are three different steps to the research when it comes to evaluating a building’s performance regarding its safety. “First, it is essential to predict and calculate accurate magnitude of an earthquake force when one is trying to build a building at a specific place,” said Han. The research used the program that predicts possible earthquake activities and its effect on other different regions within Korea. It is able to do so as the program considers all the past earthquakes which occurred in Korea, all differing in location and magnitude. With this program model that shows the scale of magnitude that affects farther locations, it is able to anticipate other possible earthquakes and their effects. An example of a simulated ground motion due to the Gyeongju earthquake. (Photo courtesy of Han) Developing an analysis model to evaluate the safety of a building The next step is also critical, which is to establish a precise analysis model to evaluate a seismic performance of a building. It is important to know whether a structure is capable of enduring the effect of earthquake. “It can be done by an experiment in a lab, but it is hard to do so with large buildings due to its size and financial issues. As an alternative, an analysis model can be used as an alternative to evaluate instead through a computer program,” said Han. It is crucial for the analysis model to be on the point to exactly evaluate other buildings’ performances. “One of the top priorities of a building when an earthquake hits, is to prevent loss of human lives. Thus, the analysis accurately predict responses of buildings structure subjected to not only small earthquake ground motion but also large earthquake ground motion causing the buildings to collapse,” said Han. Such analysis model is based on the conventional mechanics theory. But the theory itself cannot solely explain the rotation capacities of various factors inside a building due to the complexity of the components and their connections of building. It is therefore necessary to conduct experimental tests for the component of building structures to develop and improve analysis models for every parts of the building. Experiments of different parts of components are also combined to make analysis models more accurate. (Photo courtesy of Han) Last but not least, by using the developed analysis model and seismic force, it is able to evaluate the safety of a building towards an earthquake. The method of evaluating the seismic performance of a building has been developed, which can accurately assess the safety of the building both before and after it is constructed. Within the flow of Han’s research, the paper specifically contains an experiment on this level, which is evaluating the seismic performance of IMF (Intermediate Moment Frames) with connections having a rotation capacity of 0.02 radian. To put it easily, as mentioned above, it refers to the moment connections of a building and 0.02 radian is a designated minimum rotation capacity of moment connections that was defined by US seismic design standard AISC 341-10(a model standard of Korean seismic design). Through the research and experiments went on, it was observed that the rotation capacity of 0.02 radian could not successfully guarantee the satisfactory seismic performance of IMFs. Thus, the paper suggested the number of rotation capacity to improve the safety standard. The following research that Han and his co-researchers are committed to is quite promising, as it is currently being introduced to the architectural standards of the US. “We hope our research could later motivate domestic buildings to meet safer standards,” concluded Han. "I hope my research could contribute to the making of a safer world against earthquakes." Yun Ji-hyun uni27@hanyang.ac.kr Photo by Choi Min-ju

2016-11 28 Important News

[Academics]Unified Model of a Minute World

Professor Cho Jun-hyeong of Department of Physics is interested in the study of low-dimension nanomaterial of one and two dimensional nanostructures formed on the surface of solid matters. Working as an editorial staff of Scientific Reports, a sister magazine of Nature, Cho is the member of the Korean Physical Society, American Physical Society, and the Korean Vaccum Society. Cho's paper, completed with a second editor, Lee Se-ho (Physics, Doctoral program), 'Dimensionality and Valency Dependent Quantum Growth of Metallic Nanostructures: A Unified Perspective', suggests a unitary, simple model that explains the preferred length and thickness of nanowires and nanofilms made by various kinds of metals, by using diameter of the nanostructure and the phenomenon called Friedel Oscillations. Cho embodies himself in the field of nanostructures. (Photo courtesy of Cho) The atoms of a solid mass are arranged in a periodical manner. However, there is a phenomenon which breaks this periodicity, called crystallographic defect. For example, if an atom is not present where it should be situated, it is called point defect. In addition, planar defect occurs when many atoms do not exist in a surface form. Nanowires that are covered in Cho’s paper have point defect from a certain place of their infinite length. On the other hand, nanofilms have planar defect from some amount of their infinite width. When defects of a solid mass occur, the electrons of solid matter and the defects interact together, forming a density wave named Friedel Oscillations. Friedel Oscillations are a similar to water waves made when a rock is thrown on the surface of a calm lake. In the study, Cho discovered that nanowires are energetically stable at the length that matches the wavelength of Friedel Oscillations. The period of Friedel Oscillations is determined by the composition and diameter of the nanostructure. Cho found that the preferred length of the nanowire and thickness of nanofilm, called magic length and magic thickness, differentiates depending on the diameter of the nanowire and its metal component. Cho found out that as the diameter of nanowire extended, the period where magic length occurs differs in length in accordance with the type of metal. The period of alkali metals and group IB metals (copper, silver, gold) increased as the diameter of nanowire elongated. In the case of transition metals and groups IIIA to VA metals, the period decreased. The structure of nanomaterials (left) and the magic length of nanowires composed of diverse metals (right). (Photo courtesy of Cho) Cho confirmed the structural stability of nanowires by changing their diameters. When the diameter of a nanowire is more than 10Å [Å: angstrom, unit of length equal to 6990100000000000000♠10−10 m], it can be called a nanoisland. If the diameter of the nanowire becomes infinitely large, it will become a nanofilm. “In this study, we found that when the diameter of the nanowire is increased, the vibration period becomes the same as that of the nanofilm, also being saturated,” Cho said. This means that when the diameter of the nanowire becomes larger, the magic length equals the magic thickness of the nanofilm. The reason for this saturation of the oscillation period is because the Friedel Oscillations are the same in the case of the above two systems. There was a need for a comprehensive theory that encompasses studies on nanowires and nanofilms that have been ensuing for the past 30 years, because there was a lack of unified understanding about different magic lengths, and the thickness of nanowires and nanofilms from diverse substances. “I believe that finding new puzzle pieces has a lot of meaning but putting those piled pieces together into a big picture is also very significant,” Cho emphasized. “This research may spur motivation for other research on new nanostructures, since it explained a preferred length and thickness in a uniform approach when low-dimensional nanostructures are formed,” he added. Currently, Cho is handling a joint study with University of Science and Technology of China (USTC) and Zhengzhou University's research teams, as well as continuing theoretical research on different nanostructures. The research plan of Cho’s laboratory is to proceed with a study which combines surface, nano, and topology fields. Not only has Cho achieved great accomplishments in the field of nanostructures, but he is concerned about his students who would lead the scientific domain in the future. “I am trying to offer students a lot of experiences, such as encouraging them to attend academic conferences. I also try to converse with them, because science can advance in that way- through involvement and communication,” he said. Cho thinks what professors, schools, and the government should aim to create suitable atmospheric and foundational provisions for science students for them to focus on their work. Jang Soo-hyun luxkari@hanyang.ac.kr

2016-11 20 Important News

[Academics]Institutionalization of the green certification scheme

Professor Kim Hong-bae of the Department of Urban Planning & Engineering is an expert in the field of urban planning. His paper, “A cost-benefit analysis for the institutionalization of the green certification scheme”, discusses about what would be beneficial when it comes to achieving the green certification. Green certification is the standardized certificate used to prove the suitability of Green technology and products. As for other developed countries, there has been green certifications since the 1990s following the concerns of environmental pollution. For instance, Great Britain has the BREEAM, Japan has CASBEE and United States has the LEED. These institutionalized green certificates are competing to become the world standard. Although Korea now has GBCC, it is not institutionally stabilized compared to other countries yet. Other countries provide the green certification in terms of community, rather than single building itself while Korea is on its way to broadening its spectrum towards giving communities the green certification. ▲ Kim explains about the green certification What is so special about Kim’s paper was that it has provided a deep insight into whether green certification was something that really provides people with benefits in life or not. Through the cost benefit analysis, he has provided the guidelines to how the system would be generally constructed. By providing low carbonizing 45 sectors ranging from industry to policies, Kim has divided the qualification standard and it has its meanings in that social costs and benefits are derived. Most of the standards are very straightforward. However, there are some of the ambiguous points to be digitized into measurements which include pride or self-esteem. Most of the measurements are easier to make for instance, the market value of the house that individuals live in. However, it is hard to show the pride in terms of numerical values to be seen. This is where the contingent valuation method (CVM) comes into action. This explains the “willingness to pay” and digitizes the inherent value inside individuals. ▲ Kim expresses that energy should be saved Some of the studies that Kim is engaged in currently is related to energy harvesting. By recycling the energy wasted into creating a new source of energy, it has its huge meanings. Also, Kim has pointed out a special point in that electric cars do not actually lower the carbon dioxide level nationally. “Although in regions where electric cars operate will show lower signs of carbon dioxide level, the regions where electricity is produced will show greater levels of carbon dioxide which means that nationally, it breaks even,” said Kim. The goal of Kim’s studies leads to one simple logic. In order to achieve low carbon, low energy comes first. The responsibility to saving energy would lead to a lower level of carbon dioxide, which is believed to be one of the worst factors that affect global warming. People need to actively engage in actions such as car sharing or even the smallest actions such as saving water, electricity and the environment as a whole. Kim Seung-jun nzdave94@hanyang.ac.kr

2016-11 14

[Academics]Architecture Over the Centuries

Professor Nam Sung-taek of the Department of Architecture holds his prime interest in the comprehensive theory of symphonizing diverse scales of artificial environmental design from a small-scaled objet—a French word meaning object, material, or thing—to a large-scaled city. In his paper, 'The Effect of Everyday Objects on Indoor Remodeling: Loos and Le Corbusier, 'Housing Professors' ', Nam minutely elucidated the relationship between objets and space, which all together contribute to the principles of architecture. He also accounted for the change of the roles of architects and the definition of architecture design as a result of the shift in production of goods from artisan’s craftsmanship to mass production in factories as industrialization took place in the 20th century. Shift in the Role of Architects ▲ Nam explains that an architect is not a form master but a housing professor. Up until the early 20th century, the idea of total art was dominant in the field of architecture. It is a system in which an architect designs not only the architecture itself but also what is contained within and stands around that construction, from the objets that relate to everyday life including spoons and chairs to the entire city at large. In other words, an architect used to design everything from an objet to the whole city, becoming a “form master” who created and designed small objets, spaces, and architectures that eventually expanded and came together to form a city. It was not only the buildings themselves that portray the architect’s work but also what is in the building and how the objets were put in place as well. This convention often emphasized the artistic work that regarded the whole city as one architect’s art work, giving rise to the concept of total art again. The architects who sought the ideals of total art were tossed with an insurmountable dilemma—whether to reject or accept the shift—as the industrialized city began producing things that could not be hand-made and that which were more readily accessible, suggesting an alternative option for the residents to design their own homes instead of entrusting the experts. In the face of such confusion, two architects who proposed a new notion at the time were Adolf Loos of Austria and Le Corbusier of Switzerland. The two architects embraced the on-going change and adjusted the principles of architecture accordingly, pioneering a concept called 'housing professor', which pointed out that architects are no longer form masters but teachers who educate people on residence and living: that is, training them how to select the appropriate objets for individual’s houses, rather than designing every little piece in a work. Their proposition allowed the residents to scheme their own houses by choosing objets that suited their taste and personality, creating what is like a personal 'museum' or 'gallery'. “I admire the two outstanding architects in many aspects. They did not simply encage themselves within the traditional boundaries of architecture and rejected external factors such as changes or surrounding environments but attentively examined all the potential influences around them that might have an impact on their work. Embracing and incorporating the on-going circumstance candidly was the key to permitting further improvements to breakthrough. To create every piece of a complete architecture from an objet at small to a city at large, the two architects observed and applied the outside forces into their architecture and did not hesitate to change their views if necessary,” noted Nam. Contemporary Architecture It was not so strange in the past for an individual to seek the help of an architect to design the doors and tables to be placed in their houses. However, industrialization pivoted this perspective, by letting individuals to freely choose and customize the designs of their houses. Consequently, the opposite is true today. people seldom desire guidance of architects and prefer to independently pick the objets and sketch their own rooms when it comes to architecture. On this note, with people having much interest in designing their residences, Nam hopes those interests connect to the study of architecture, which became too cultural to be solely considered as an academic branch nowadays. He hopes that architecture will mean something more than just a part of industry and highlight its cultural aspect which can be a crucial part in our history. ▲ Nam pinpointed that architecture is part of our culture and history. Jeon Chae-yun chaeyun111@hanyang.ac.kr Photos by Choi Min-ju

2016-11 07

[Academics]Finding a Way to Develop Better Algorithms

Professor Koh Young-woo of the Department of Economics and Finance is an expert in the field of microeconomic theory, market design and mechanism design. His main research interest is relevant to studies of matching and auction theory. His recent paper, “Decentralized College Admissions” researched on decentralized college admissions with uncertain student preferences. Since schools strategically target students when students’ preferences of schools are unknown, a matching between colleges and students is often inefficient and unfair. Koh wrote the paper to detect unfairness in college admissions. “When colleges admit students every new year, they strategically accept some students who are possibly overlooked by other colleges, or competitors. When that happens, highly ranked students, who are better qualified in their scores, essays, or interviews perhaps, may receive fewer admissions or have a higher chance of receiving no admissions than those students who are ranked below,” explained Koh. In the paper, there are two colleges, each with its limited capacity of students they can admit, and a unit mass of students. Colleges make admission decisions based on two attributes of a student: a score that is common to all colleges, and a ‘fit’ that is college specific (essays, exams, or extra-curricular activities). Colleges rank students according to their scores and fits but they have no way to observe students’ preferences, which causes uncertainty. While such uncertainty leads to unfair outcomes, it also shows inefficient equilibrium as some colleges leave their seats unfilled although there are unmatched students who could have been welcomed by other colleges. “Thus, strategic targeting and biased admissions make the outcome also unfair in other dimensions. It creates what is called ‘justified envy’, when a mass of students are unable to enroll in their preferred schools because the schools are taking students who are ranked below them,” said Koh. To cope with such congestion, colleges employ additional measures like restricting the number of applications students can apply to or admitting students in sequence by putting them on the waiting list. However, it is hard to say that these additional measures eliminate aforementioned undesirable outcomes. Even when colleges make their waiting lists, it is hard to determine or expect which students will enroll as time is limited for the students to make their choices. The solution to this problem could be to centralize the matching through ‘deferred acceptance’. Deferred acceptance can be seen when students apply to high schools. It was actually devised and used in New York. Students report their preference orders to the clearing house, which then the information is used to simulate the following algorithm: at the first round, students apply to their most preferred schools, and the schools tentatively admit favorable students up to their capacities and reject the rest. The rejected students then apply to their second choice, and the schools reject lower-ranked students below their capacities. This process is repeated until no further applications are made. “More students are satisfied by this method, as more students and schools can find a better match for one another,” said Koh. Unfortunately, it is hard to expect a centralized admission in colleges as there are different qualifications schools want from students unlike high schools. Different and complex admissions are less likely to be perfectly merged into a single algorithm. “Thus, more research and studies have to be followed to develop a better algorithm to reduce unfairness, and to increase efficiency and effectiveness of the matches,” added Koh. “I think new ways of matching in many other circumstances like donating organs and allocating teachers in public schools can improve the outcomes better,” asserted Koh. “While the resources are limited and there are more people who want it, we can better utilize resources just by allocating with more efficiency, leaving more people satisfied as a result.” Koh will be researching further on matching. Its mechanisms is hoped to be applied to different circumstances in our society. Yun Ji-hyun uni27@hanyang.ac.kr Photos by Choi Min-ju

2016-11 01

[Academics][Researcher of the Month] Professor Paik Un-gyu

Professor Paik Un-gyu of the Department of Energy Engineering is November's Researcher of the Month for his active role in exploring the field of energy engineering. Recently, he has led a research team in developing significant improvement of sodium-ion batteries (SIBs), explained in the paper, 'SB@C coaxial nanotubes as a superior long-life and high-rate anode for sodium ion batters'. This specific study focuses on ways to increase the efficiency of the sodium-ion battery, which can possibly replace the popular lithium-ion batteries. Paik spoke about his study as well as his experience as a professor. (Photo courtesy of Paik) “There are other excellent professors who deserve this honor for than me. Yet, I am still very thankful for it,” said Paik. “The research was about sodium-ion batteries, which is rarely known to the public. The main objective was to reduce problems and improve effectiveness of sodium-ion batteries to replace lithium-ion batteries in the future.” Currently, lithium-ion batteries are commonly used in various electronic devices including smartphones. However, the main problem of lithium-ion batteries is the cost of lithium itself. There are certain limits for the Korean government to secure enough lithium mines from overseas. Therefore, a more parallel, affordable solution is to replace lithium with sodium in making ion batteries. Similar to lithium-ion batteries, sodium-ion batteries have issues of rapid operating-capacity fading due to large volume expansion during sodiation. Sodiation is the process of using sodium for a battery. Smartphone batteries bubbling up like a balloon is an example of volume expansion in lithium-ion batteries. “To reduce volume expansion, we tuned the morphology and structure at the nanoscale using carbonaceous materials as the buffer layer,” explained Paik. “Hence, a carbon-coating with a thermal reduction strategy was developed to create a unique tube-like structure, known as Sb@C coaxial nanotubes.” In other words, the hollow space within the specially-created tube can make space available for the accommodation of volume expansion. Another way to increase sodium-ion batteries' efficiency is to improve the charge and discharge system. The charging speed of a battery depends on electron conduction; how fast electrons move within its electric field. Carbon-coated nanotube, a conduction material, allows the conduction of electrons to quicken and enables diffusion to take place, making both sides of the tubes accessible for the charging system. Therefore, by reducing the risk of volume expansion and enhancing the charge system, sodium-ion batteries can be applicable in replacing lithium-ion batteries. The nanotube enhances the quality of sodium-ion batteries. (Photo courtesy of RSC Publisher) Other than this specific study, Paik has contributed immensely in researching applicable, practical studies of nanoparticles and nanodevices used in semiconductors. Most of his studies focus on what can be done to improve technology by working with industries in various sectors. “I personally believe that the reason why I am a researcher is to find practical ways to help the society. The fundamental studies are also important, but I tend to use the basic principles to apply them to real and effective technology,” said Paik. His passion for energy engineering has led him to become one of the professors to have published the most research papers at Hanyang University. Like his accomplishment in energy engineering research, Paik emphasized the need for passion for students who strive for success. “Today, we are facing a more skill-intensified society where work requires advanced expertise in an area. As learners, students must have passion for studying,” said Paik. “Even though the society is rapidly changing at each moment, if students take consistent steps through learning, it can be a strong benefit for them once they have amassed required knowledge.” As a professor, Paik has guided many students in taking the same steps that he himself has gone through for the past 24 years of learning and researching. “In science, understanding the boundaries of each important experiment is necessary, which must be overcome to produce an outcome. Likewise, I hope my role as a professor can assist students to overcome those limitations.” As a professor, Paik guides students to strive for success. (Photo courtesy of Paik) Park Min-young minyoungpark118@gmail.com

2016-10 24

[Academics]Buddha-in-Eye Community, Utopian Solution for Contemporary Society

Professor Lee Do-heum of the Department of Korean Language and Literature is interested in finding solutions to problems in the current society by comparing and contrasting Eastern and Western philosophy and Buddhism. He is the chairman of an alternative university established by the Knowledge Circulation Cooperation Association, was an editor for the Buddhism Review, and the head of HYU Research Institute for Korean Studies until 2008. His paper, “Buddhist Countermeasure against Obstacles to Sustainable Development”, explains how to solve environmental and economic crises of the modern day with Buddhistic solutions. The paper was presented at the 2016 Asia Youth Academy and Asian Theology forum held on August 24th this year, which drew in scholars from 14 nations. Professor Lee is interested in finding solutions for problems of the modern society by observing philosophical thoughts of the East and West, including Buddhism. “Today's environmental crisis is severe enough to render all of human civilization extinct. 38% of life on Earth has already diminished, and there are approximately 1.8 billion who are starving to death, or are in desperate need of clean water.” According to Lee, if societies continue as they are, the world would be at the verge of dystopia or might not exist altogether by the 22th and 23th century. Lee says that the core reason for these issues is capitalism, and that coming up with a new form of societal order is the responsibility of every human being. “The fundamental obstacle that prevents sustainable development is capitalism. Capitalistic societies do not have respect toward humans, life or ecology. Every value is converted to money.” According to Lee, mud flats are destroyed to secure more lands and develop constructions, eliminating living things and thus destroying nature. A criminal can kill a woman, a wife and a mother of two children, for 150,000 won, with no consideration for her family or friends. Lee said that capitalism could not last long, pointing out that the earned gains, which stood at 46% in the year 1869, is now greatly reduced to 5%. In addition, government debts have exceeded GDP at present. As a solution for the problems caused by capitalism, Lee suggested his own idea of society, named 'Buddha-in-eye community'. Buddha-in-eye community is a world that breaks the law of competition. Individuals find freedom by aiding others, reach self-realization by laboring, and reform by performing ascetism. Buddha-in-eye means that we acknowledge people's differences by looking into one another's eyes. Accepting discrepancy for coexistence is very important in order to prevent evil and the violence that occur due to reinforcements for conformity. Lee referred to the Nazis' hate speech, which brainwashed Germans to oppress the Jews, as a corresponding example that intensifies the idea of extreme 'oneness'. This led to tragedies such as the Holocaust. When one is aware and receptive of diversity among people, one should sympathize with others’ pain with love and mercy and try to help one another. Lee believes that all humans possess the nature of Buddhahood, which allows them to form a moral society by cooperating towards ethical development- not only for individuals but for entire communities. “Buddha-in-eye community is operated through a system of shared economy. For instance, if a design corporation needs more energy, the company would receive it via a control tower from where the leftover energy is. Then the company may offer a design program to where it was granted energy- like a barter economy.” Lee also gave real-life examples of Buddha-in-eye community. Sungshimdang, a famous bakery in Daejeon for its fabulous taste and its hearty business culture, donates 3,000 loaves of bread to 150 places and pays employees only 15% of its profits. Currently, Lee is trying to apply this concept to the real world by establishing an alternative university in 2015, located in Eunpyung-gu, Seoul, to allow students to learn the spirit of cooperation and sympathy in political, economic, cultural, and social aspects. Professor Lee believes that we are able to develop an ideal society where coexistence and fair allocation prevail. Lee is planning to continue developing ideas that merge philosophical thoughts of the East and West, and actualizing beliefs by putting his ideas to practice in the local society even after his retirement. Coming up with ideas that deal with environmental and economic problems of the modern society, participating in social movements, and instituting alternative universities are his plans. “Some say my ideas are great but difficult to materialize in reality. Even so, consider the fact that in the 18th century, it was preposterous to think that every man should be treated equally.” Lee believes that if an idea is legitimate, it has the potential to be fulfilled. Ideal dreams and limitations of reality coexist. Perceiving the confines of reality and suggesting the kind of utopia that fits in with the situation at hand is needed for the creation of a better society. Jang Soo-hyun luxkari@hanyang.ac.kr Photos by Kim Youn-soo