• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.607-616
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• 2015

The demand for cars has been so steadily increasing based on the economic growth that the number of registered cars reached 18,870,000 as of the end of December, 2012. Due to this, the demand for the parking lots also rises continuously. Because of the limited ground space, the buildings ever becoming larger, and the trend of underground parking spaces, recent parking spaces are generally constructed underground. Accordingly, the parking lot ramps slope is limited to less than 17% by relevant laws to ensure the driver safety. However, when a driver enters a parking lot ramps whose slope is slightly steep, he frequently experiences his car body colliding with ramp brackets and often sees the scratches on ramp floor. Thus, this study is intended to prevent any damage to a structure and to contribute to ensuring the riding comfort and safety of drivers and passengers by presenting the details of proper vertical curve to prevent the collision of vehicles with ramp brackets through a vertical analysis of the first and last parts of a parking lot ramps. Because it is necessary to decide the appropriate and suitable vertical slope of a parking lot ramps, this study first identified the problems through site inspection, targeting the parking lot ramps of large buildings frequently that are used by many random people. Next, the possibility of mutual collision was assessed through a theoretical analysis of the first and last parts of a parking lot ramps. Lastly, the vertical curve of a parking ramp was analyzed to estimate its details, which was presented in this study. In conclusion, if the vertical curve presented through this study is used, it will help prevent any damage to the cars and structures, ensure the riding comfort and safety of the drivers, and further reestablish the criteria for vertical installation of a parking lot ramps.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.68.1-68.1
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• 2012

The best part of graphene is - charge-carriers in it are mass less particles which move in near relativistic speeds. Comparing to other materials, electrons in graphene travel much faster - at speeds of $10^8cm/s$. A graphene sheet is pure enough to ensure that electrons can travel a fair distance before colliding. Electronic devices few nanometers long that would be able to transmit charge at breath taking speeds for a fraction of power compared to present day CMOS transistors. Many researches try to check a possibility to make it a perfect replacement for silicon based devices. Graphene has shown high potential to be used as interconnects in the field of high frequency electrical devices. With all those advantages of graphene, we demonstrate characteristics of electrical and optical properties of graphene such as the effect of graphene geometry on the microwave properties using the measurements of S-parameter in range of 500 MHz - 40 GHz at room temperature condition. We confirm that impedance and resistance decrease with increasing the number of graphene layer and w/L ratio. This result shows proper geometry of graphene to be used as high frequency interconnects. This study also presents the optical properties of graphene oxide (GO), which were deposited in different substrate, or influenced by oxygen plasma, were confirmed using different characterization techniques. 4-6 layers of the polycrystalline GO layers, which were confirmed by High resolution transmission electron microscopy (HRTEM) and electron diffraction analysis, were shown short range order of crystallization by the substrate as well as interlayer effect with an increase in interplanar spacing, which can be attributed to the presence of oxygen functional groups on its layers. X-ray photoelectron Spectroscopy (XPS) and Raman spectroscopy confirms the presence of the $sp^2$ and $sp^3$ hybridization due to the disordered crystal structures of the carbon atoms results from oxidation, and Fourier Transform Infrared spectroscopy (FTIR) and XPS analysis shows the changes in oxygen functional groups with nature of substrate. Moreover, the photoluminescent (PL) peak emission wavelength varies with substrate and the broad energy level distribution produces excitation dependent PL emission in a broad wavelength ranging from 400 to 650 nm. The structural and optical properties of oxygen plasma treated GO films for possible optoelectronic applications were also investigated using various characterization techniques. HRTEM and electron diffraction analysis confirmed that the oxygen plasma treatment results short range order crystallization in GO films with an increase in interplanar spacing, which can be attributed to the presence of oxygen functional groups. In addition, Electron energy loss spectroscopy (EELS) and Raman spectroscopy confirms the presence of the $sp^2$ and $sp^3$ hybridization due to the disordered crystal structures of the carbon atoms results from oxidation and XPS analysis shows that epoxy pairs convert to more stable C=O and O-C=O groups with oxygen plasma treatment. The broad energy level distribution resulting from the broad size distribution of the $sp^2$ clusters produces excitation dependent PL emission in a broad wavelength range from 400 to 650 nm. Our results suggest that substrate influenced, or oxygen treatment GO has higher potential for future optoelectronic devices by its various optical properties and visible PL emission.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.1
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• pp.55-68
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• 2020

In order to investigate the hydraulic characteristics of a boundary layer streaming over the beach cusps appeared in swells prevailing mild seas, we numerically simulated the shoaling process of Edge waves over the beach cusp. Synchronous Edge waves known to sustain the beach cusps could successfully be duplicated by generating two obliquely colliding Edge waves in front of beach cusps. The amplitude A_B and length L_B of Beach Cusp were elected to be 1.25 m and 18 m, respectively based on the measured data along the Mang-Bang beach. Numerical results show that boundary layer streaming was formed at every phase of shoaling process without exception, and the maximum boundary layer streaming was observed to occur at the crest of sand bar. In RUN 1 where the shortest waves were deployed, the maximum boundary layer streaming was observed to be around 0.32 m/s, which far exceeds the amplitude of free stream by two times. It is also noted that the maximum boundary layer streaming mentioned above greatly differs from the analytical solution by Longuet-Higgins (1957) based on wave Reynolds stress. In doing so, we also identify the recovery procedure of natural beaches in swells prevailing mild seas, which can be summarized such as: as the infra-gravity waves formed in swells by the resonance wave-wave interaction arrives near the breaking line, the sediments ascending near the free surface by the Phase II waves orbital motion were carried toward the pinnacle of foreshore by the shoreward flow commenced at the steep front of breaking waves, and were deposited near the pinnacle of foreshore due to the infiltration.

• Journal of The Korean Association For Science Education
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• v.41 no.5
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• pp.429-440
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• 2021

In this article, we explored the value of interculturalism in developing the discourses of international cooperation in science education. By doing so, we interviewed four teachers who had an experience in teaching science in developing countries, and analyzed their experiences and perceptions in the lens of interculturalism and dialogue. Our analysis of teacher narratives shows the transition in the teachers' perspectives from volunteering and transmission to collaboration and learning. The transition from volunteering to collaboration occurred as the teachers learned how to meet 'the others' as themselves being strangers in the foreign context. Through intervening and colliding, teachers were able to reposition their identities as teachers. Furthermore, their science teaching practices show how the teachers tried to negotiate between the universal or idealistic value of science education and the heterogeneities formed by the country's cultural and specific situation of science education. Through these experiences, the teachers began to understand the importance of the culturally specific 'need' for science education. In conclusion, we proposed a discourse of science education collaboration based on interculturalism in terms of the diversity and complexity of science education practices in developing countries, teacher professionalism, culturally relevant pedagogy and sustainable policy.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.10
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• pp.1331-1340
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• 2020

Object detection in maritime means that the captain detects floating objects that has a risk of colliding with the ship using the computer automatically and as accurately as human eyes. In conventional ships, the presence and distance of objects are determined through radar waves. However, it cannot identify the shape and type. In contrast, with the development of AI, cameras help accurately identify obstacles on the sea route with excellent performance in detecting or recognizing objects. The computer must calculate high-volume pixels to analyze digital images. However, the CPU is specialized for sequential processing; the processing speed is very slow, and smooth service support or security is not guaranteed. Accordingly, this study developed maritime object detection software and implemented it with FPGA to accelerate the processing of large-scale computations. Additionally, the system implementation was improved through embedded boards and FPGA interface, achieving 30 times faster performance than the existing algorithm and a three-times faster entire system.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.300-307
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• 2022

Time-resolved serial femtosecond crystallography (TR-SFX) is a powerful technique for determining temporal variations in the structural properties of biomacromolecules on ultra-short time scales without causing structure damage by employing femtosecond X-ray laser pulses generated by an X-ray free electron laser (XFEL). The mixing rate of reactants and biomolecule samples, as well as the hit rate between crystal samples and x-ray pulses, are critical factors determining TR-SFX performance, such as accurate image acquisition and efficient sample consumption. We here develop two distinct sample delivery systems that enable ultra-fast mixing and on-demand droplet injecting via pneumatic application with a square pulse signal. The first strategy relies on inertial mixing, which is caused by the high-speed collision and subsequent coalescence of droplets ejected through a double nozzle, while the second relies on on-demand pneumatic jetting embedded with a 3D-printed micromixer. First, the colliding behaviors of the droplets ejected through the double nozzle, as well as the inertial mixing within the coalesced droplets, are investigated experimentally and numerically. The mixing performance of the pneumatic jetting system with an integrated micromixer is then evaluated by using similar approaches. The sample delivery system devised in this work is very valuable for three-dimensional biomolecular structure analysis, which is critical for elucidating the mechanisms by which certain proteins cause disease, as well as searching for antibody drugs and new drug candidates.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.1
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• pp.44-51
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• 2023

The Convention on the International Regulations for Preventing Collisions at Sea, 1972 (COLREGs) was adopted to prevent ships from colliding with other ships or any object such as the seabed. COLREGs have been codified and refined since the mid-19th century, and have reached the present. Therefore, the terms and sentences used in COLREGs also have distinct academic and legal connotations. However, in the Maritime Safety Act of the Republic of Korea, which translated COLREGs into domestic law, the "risk of collision" and the "danger of collision" was used in the law without distinguishing their meanings. Accordingly, the difference between "risk" and "danger" was analyzed with reference to the definition of risk by an authoritative international organization of the United Nations such as the International Maritime Organization and the International Organization for Standardization as a well-known and authoritative non governmental organization. In addition, the cases codified in COLREGs and translated cases in the Maritime Safety Act were analyzed to highlight the need for amending the Maritime Safety Act. From the perspective of safe navigation, it is expected that the Maritime Safety Act in the future would distinguish between "danger" and "risk" so that the efforts of watch officers to prevent collisions could be further systematized.

• Korean Journal of Culture and Social Issue
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• v.29 no.4
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• pp.617-636
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• 2023

The goal of this study was to explain the phenomenon of making efforts to overcome the need-reality collision as a cultural characteristic of Koreans. Specifically, we examined whether the behavior varies depending on the degree of relational agency in the situation where conflicts between one's needs and reality have occurred. To this end, a total of 217 participants participated in the online experiment, and the data of 156 participants were finally analyzed. After responding to the relational agency scale, the participants were exposed to a decision-making scenario in which conflicting factors existed. The scenario were about buying a house and making a wedding hall contract, and in each scenario, two important values were set to conflict with each other in the market. Participants read the scenario and entered the level they wanted for each value. After that, they encounter a situation in which he or she has not found the candidate site corresponding to the level he or she wants. Then, the participants responded to their willingness to make additional efforts themselves. As a result of the study, the degree of relational agency of the participants showed a positive relationship with the degree of additional effort. In addition, the degree of the desired level beyond the reality (expectancy discrepancy) showed a nonlinear (reverse U-shape) influence on the additional effort while controlling for individual difference. Furthermore, the interaction effect between relational agency and expectancy discrepancy was significant. Specifically, individuals with low agency did not have a significant relationship between the degree of expectancy discrepancy and the dependent variable, but individuals with high relational agency had a significant non-linear relationship between the degree of expectancy discrepancy and the dependent variable. Based on the results of the study, the role and function of Koreans' psychological characteristics (relational agency) in the scene of managing needs-reality collision were discussed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.2
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• pp.1-13
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• 2012

This study aimed at learning the values and meanings of the letters carved on the rocks all over Mt. Sangdu located at the boundary between Kimje-si and Jeongeup-si of Jeollabuk-do by grasping the current state of them, investigating the patterns and contents of them, and understanding the spatial and landscape properties of the region where the rocks are scattered. The results of this study are as follows; The name of Mt. Sangdu came from the mountain with the same name located in India where Buddha were seeking the truth, and means auspicious. With the recognition of ancient maps and books, various propitious spots also made the landscape symbols of Mt. Sangdu solidify. Whoam, Chaangsuk-Kim, Weolgye Young-Cho Song and the members of Cheonggye Society like Dongcho Seok-Gon Kim led the creation of the rocks, and the 41 letter-carved rocks all over four water systems were found out and all of them were carved with Chinese characters. The letters were usually carved on flat and broad rocks, and they mainly had the shape of a small waterfall and a wide waterfall of under 1 meter height. 25(60.9%) of the carved letters were about moral training, and it seemed that they wanted to protect their pride under the shackle of the Japanese colonization over Korea. The styles of handwriting are Hangseo and Jeonseo except for names, and show various and complex styles. The mix composition of the carved letters of 'Yusubulbu(流水不腐)' of Choseo and the rocks of Takjok(濯足) is extraordinary, and the letters carved as the shape of Nakkwan(落款) have artistic value and degree of finishing. It seemed that intellectuals during the Japanese colonization over Korea in the 1930s considered Mt. Sangduasa highly valuable region because they expressed their hope and wish for the new world on the rocks. The letters on the rocks of Mt. Sangdu are invaluable cultural landscaping elements for the improvement of landscaping symbolism of Mt. Sangdu because of colliding values and spirits of the time of 'the anguish and pain of intellectuals' and 'the status of living joyfully outside of the mundane world.'

• Journal of Haehwa Medicine
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• v.27 no.1
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• pp.9-20
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• 2018

Objectives : Ten heavenly stems(10天干) and Twelve earthly branches(12地支) are symbols exposing change order in heaven and earth, and are a very important sign in studying oriental philosophy and oriental medicine. Especially, 10 heavenly stems(10天干) and 12 earthly branches(12地支) are indispensable for the study of Five Circuits And Six Qi(오운육기), and a deep study is needed. Methods : I have examined Yin Yang combination(음양배합), Five elements combination(오행배합), Six Qi 3Yin 3Yang combination(육기삼음삼양배합), viscera combination(장부배합), Mutual collision(상충), Six combination(육합), Three combination(삼합), etc. of 12 earthly branches(12지지) by referring to books such as "Yellow Emperor Internal Classic" ("黃帝內經") and "Principle of universe change" ("우주변화의 원리"). Results & Conclusions : Zi Yin Chen Wu Shen Xu(子 寅 辰 午 申 戌) become Yang(陽), Chou Mao Si Wei You Hai(丑 卯 巳 未 酉 亥) become Yin(陰), Zi Si Yin Mao Chen Si(子 丑 寅 卯 辰 巳) become Yang, and Wu Wei Shen You Xu Hai(午 未 申 酉 戌 亥) become Yin. Twelve earthly branches can be divided into five movements by its original meaning, where YinMao(인묘) is tree, SiWu(사오) is a fire, ShenYou(신유) is a gold, HaiZi(해자) is water, and ChenXuChouWei(진술축미) mediate in the middle of four movements So they become soil(土). SiHai(巳亥) is JueYin Wind Tree(궐음 풍목), ZiWu(子午) is ShaoYin Monarch Fire(소음 군화), ChouWei(丑未) is TaiYin Humid Soil(태음 습토), YinShen(寅申) is ShaoYang Ministerial Fire(소양 상화), MaoYou(卯酉) is YangMing Dry Gold(양명 조금), and ChenXu(辰戌) is TaiYang Cold Water(태양 한수). Viscera combination(장부배합) combines Zi(子) and Bile(膽), Chou(丑) and Liver(肝), Yin(寅) and Lung(肺), Mao(卯) and Large intestine(大腸), Chen(辰) and Stomach(胃), Si(巳) and Spleen(脾), Wu(午) and Heart(心), Wei(未) and Small intestine(小腸), Shen(申) and Bladder(膀胱), You(酉) and Kidney(腎), Xu(戌) and Pericardium(心包), Hai(亥) and Tri-energizer(三焦), Which means that the function of the viscera and channels is the most active at that time. Twelve earthly branches mutual collisions collide with Zi(子) and Wu(午), Chou(丑) and Wei(未), Yin(寅) and Shen(申), Mao(卯) and You(酉), Chen(辰) and Xu(戌), and Si(巳) and Hai(亥). The two colliding earthly branches are on opposite sides, facing each other and restricting each other by the relation of Yin-Yin and Yang-Yang it rejects each other so a collision occurs. Six Correspondences(六合) coincide with Zi(子) and Chou(丑), Yin(寅) and Hai (亥), Mao(卯) and Xu(戌), Chen(辰) and You(酉) and Si(巳) and Shen(申) Wu(午) and Wei(未). Three combination(三合) is composed of ShenZiChen(申子辰), SiYouChou(巳酉丑), YinWuXu(寅午戌), and HaiMaoWei(亥卯未). Three combination(三合) is composed of ShenZiChen(申子辰), SiYouChou(巳酉丑), YinWuXu(寅午戌), and HaiMaoWei(亥卯未). This is because the time Six Qi(六氣) shifts in these three years are the same.