• Journal of the Society of Naval Architects of Korea
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• v.53 no.5
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• pp.435-446
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• 2016

In this study, hydrodynamic and mooring analysis for LNG FSRU moored by an internal turret with 9 mooring lines are numerically performed using commercial softwares, Hydrostar and Ariane. Met-ocean combinations for screening method are taken from wave governed condition(BV Rule Note NR 493) with relative heading between wave and wind between −45° and +45° and relative heading between wind and current between −30° and +30°. Extreme mooring analysis and sensitivity analysis are performed for intact and damaged (=one line missing) conditions and the parameters for sensitivity analysis are wave peak period, peak enhancement factor and line pretension. In the viewpoint of the design tension in mooring line, chain diameter is designed to satisfy safety factor for each conditions. As the chain diameter is increased from 152mm to 171mm, the designtension is reduced while the minimum breaking load is increased.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.15.2-15.2
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• 2009

Manufacturing of printed electronics using printing technology has begun to get into the hot issue in many ways due to the low cost effectiveness to existing semi-conductor process. This technology with both low cost and high productivity, can be applied in the production of organic thin film transistor (OTFT), solar cell, radio frequency identification (RFID) tag, printed battery, E-paper, touch screen panel, black matrix for liquid crystal display (LCD), flexible display, and so forth. The emerging technology to manufacture the products in mass production is roll-to-roll printing technology which is a manufacturing method by printings of multi-layered patterns composed of semi-conductive, dielectric and conductive layers. In contrary to the conventional printing machines in which printing precision is about $50~100{\mu}m$, the printing machines for printed electronics should have a precision under $30{\mu}m$. In general, in order to implement printed electronics, narrow width and gap printing, register of multi-layer printing by several printing units, and printing accuracy of under $30{\mu}m$ are all required. We developed the roll-to-roll printing equipment used for printed electronics, which is composed of un-winder, re-winder, tension measurement system, feeding units, dancer systems, guide unit, printing unit, vision system, dryer units, and various auxiliary devices. The equipment is designed based on cantilever type in which all rollers except printing ones have cantilever types, which could give more accurate machine precision as well as convenience for changing rollers and observing the process.

• Progress in Superconductivity and Cryogenics
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• v.11 no.4
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• pp.12-15
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• 2009

The $I_c$ degradation behavior of critical current in differently processed YBCO and SmBCO CC tapes with IBAD template has been investigated. It has been known that the residual strain in the CC tape will influence the shape of the $I_c$-strain window; $I_c$ may show a peak value if there exist a residual strain induced in the tape during manufacturing. The difference of residual strain may be resulted from the adopted different deposition techniques. In this study, bending test of CC tapes has been done using the Goldacker bending test rig which can produce both compressive and tensile bending strain continuously or alternately to the sample. For SmBCO CC tapes, in continuous compressive bending test, $I_c$ showed a minimal increase and did not degrade up to the largest strain that can be applied using the bending rig equivalent to 1.15% based on the sample thickness. However, in the case of alternate application of compressive and tensile bending strain, $I_c$ showed a larger degradation and a lower reversible limit when compared with the case of continuous application of the bending strain. When $I_c$ started to degrade significantly at the tension side, the reversibility ended, also at the compression side which is resulted from the permanent deformation like delamination or cracks that was induced due to tensile bending strain.

• Korean Journal of Radiology
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• v.24 no.8
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• pp.752-760
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• 2023

Radiologists and trauma surgeons should monitor for early killers among patients with thoracic trauma, such as tension pneumothorax, tracheobronchial injuries, flail chest, aortic injury, mediastinal hematomas, and severe pulmonary parenchymal injury. With the advent of cutting-edge technology, rapid volumetric computed tomography of the chest has become the most definitive diagnostic tool for establishing or excluding thoracic trauma. With the notion of "time is life" at emergency settings, radiologists must find ways to shorten the turnaround time of reports. One way to interpret chest findings is to use a systemic approach, as advocated in this study. Our interpretation of chest findings for thoracic trauma follows the acronym "ABC-Please" in which "A" stands for abnormal air, "B" stands for abnormal bones, "C" stands for abnormal cardiovascular system, and "P" in "Please" stands for abnormal pulmonary parenchyma and vessels. In the future, utilizing an artificial intelligence software can be an alternative, which can highlight significant findings as "warm zones" on the heatmap and can re-prioritize important examinations at the top of the reading list for radiologists to expedite the final reports.

• Korean journal of communication and information
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• v.41
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• pp.75-107
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• 2008

The paper aims to figure out the meaning of money in terms of communication in which we can find the specific communicative and cultural form of money. In the modern capitalist society, we cannot limit money within the economical terms - for example, store of value, medium of exchange, unit of account and means of payment - because money mediates all human activities beyond the economic boundary and conveys specific meaning in the social and the cultural area. Money can be the medium of the cultural and the communicational as well as the medium of the economic. In this respect, we've try to articulate money with linguistic or semiotic insight. Through this theoretical dialogue, we find two significations of money as a medium of communication. The first signification is meta-signification which drives the individual to the unlimited accumulation of the money. Meta-signification displace the second signification of the money that is the singular, over-determined and the mosaic significations. In this process money can be the signifier without signification. And then, money is the Master signifier which all sign should be identified imaginary. Finally, Money is not only the re-presense (Darstellung) of all sings but also the representative (Vertretung) of all signs. But this double position creates some tensions and makes master signifier of money unstable. Man's analysis of Bonapartism, which shares the linguistic or semiotic insight, shows the crack of the re-presence between the representative. Like Marx's analysis, the money has the tension between two signification which makes the room for the struggle to signify.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.21-29
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• 2023

In this study, the stress characteristics of temporary fixed steel rods were analyzed in the "temporary fixing system using internal prestressing tension", which is mainly applied to the construction of superstructures by FCM. It was difficult to confirm the changes in initial tensile force in this system because the steel rod was internally connected to the pier and the PSC BOX. Therefore, measurement was performed before and after the completion of each segment using an FBG sensor to measure the change in the micro length of the steel rod. The results of the analysis showed that 75% to 90% of the maximum vertical contraction of the steel rod that occurred until the completion of the cantilever segment occurred in the fixing ~ 1segment, and the maximum loss of initial prestressing force was 39%. Such excessive loss of tension force to 1 segment means that tension is needed to improve the precision of construction during the fixation, and re-tension is needed to secure stability for conduction of cantilever segments after the completion of 1segment. In the 2 ~ last segment, the stress of the steel rod decreased gradually, and in the summer, the decrease in stress tended to partially recover due to the increase in the length of the steel rod corresponding to the increase in the vertical volume of PSC BOX. The dominant factor in the stress change in 2~ last segment in this phenomenon is judged to be the change in the length of the steel rod according to the temperature. Unlike the change in length, the relaxation was 1.2-2.7%, which was mostly offset by the opposite stress corresponding to the temperature stress. Therefore, a plan was proposed to improve the internal stress, such as adjusting the fixation time.

• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.275-283
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• 2012

Steel Plate for Rebar Connection was recently developed to splice rebars in delayed slab-wall joints in high-rise building, slurry wall-slab joints, temporary openings, etc. It consists of several couplers and a thin steel plate with shear key. Cyclic loading tests on slab-wall joints were conducted to verify structural behavior of the joints having Steel Plate for Rebar Connection. For comparison, joints with Rebend Connection and without splices were also tested. The joints with Steel Plate for Rebar Connection showed typical flexural behavior in the sequence of tension re-bar yielding, sufficient flexural deformation, crushing of compression concrete, and compression rebar buckling. However, the joints with Rebend Connection had more bond cracks in slabs faces and spalling in side cover-concrete, even though elastic behavior of the joints was similar to that of the joints with Steel Plate for Re-bar Connection. Consequently, the joints with Rebend Connection had less strengths and deformation capacities than the joints with Steel Plate for Re-bar Connection. In addition, stiffness of the joints with Rebend Connection degraded more rapidly than the other joints as cyclic loads were applied. This may be caused by low elastic modulus of re-straightened rebars and restraightening of kinked bar. For two types of diameters (13mm and 16mm) and two types of grades (SD300 and SD400) of rebars, the joints with Steel Plate for Rebar Connection had higher strength than nominal strength calculated from actual material properties. On the contrary, strengths of the joints with Rebend Connection decreased as bar diameter increased and as grade becames higher. Therefore, Rebend Connection should be used with caution in design and construction.

• Advances in pediatric surgery
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• v.17 no.2
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• pp.170-178
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• 2011

Hiatal hernia is a very rare disease in the pediatric population. However information from our esophageal atresia postoperative follow-up program has hypotheses; "Hiatal hernia may more frequently occur in postoperative esophageal atresia patients (EA group) than in the general pediatric population (GP group)" and "The tension on the esophagus after esophageal anastomosis may be an important etiologic factor of hiatal hernia in EA group". To prove the first hypotheses, we compared the incidence of hiatal hernia in the GP group with the incidence in the EA group. The Incidence in the GP group was obtained from national statistic data from Statistics Korea and Health Insurance Review and Assessment Service of Korea. The incidence in the EA group was obtained from the medical record and the imaging studies of our esophageal atresia postoperative follow-up program. To prove the second hypothesis, the presumptive risk factors for the development of hiatal hernia in EA group, such as the type of esophageal atresia, degree of esophageal gap, the stage operation and the redo-operation with resection and re-anastomosis of esophagus were analyzed statistically. The total number of patients in the EA group was ninety-nine and there were 5 hiatus hernias. The incidence of EA group (5 %) is significantly higher than incidence of GP group (0.024 %). (p=0.0001) The statistical analysis of the presumptive risk factors for hiatal hernia development in EA group failed to show any evidence of correlation between postoperative esophageal tension and the hiatal hernia. This study shows that the postoperative patients with esophageal atresia have high occurrence of hiatal hernia and should be followed up carefully to detect hiatal hernia.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.162-176
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• 2022

In Lead-based reactor (LBR) severe accident, the meltdown and migration inside the reactor core will lead to fuel fragment concentration, which may further cause re-criticality and even core disintegration. Accurately predicting the migration and solidification behavior of melt in LBR severe accidents is of prime importance for safety analysis of LBR. In this study, the Moving Particle Semi-implicit (MPS) method is validated and used to simulate the migration and solidification behavior. Two main surface tension models are validated and compared. Meanwhile, the MPS method is validated by the L-plate solidification test. Based on the improved MPS method, the migration and solidification behavior of melt in LBR severe accident was studied furthermore. In the Pb-Bi coolant, the melt flows upward due to density difference. The migration and solidification behavior are greatly affected by the surface tension and viscous resistance varying with enthalpy. The whole movement process can be divided into three stages depending on the change in velocity. The heat transfer of core melt is determined jointly by two heat transfer modes: flow heat transfer and solid conductivity. Generally, the research results indicate that the MPS method has unique advantage in studying the migration and solidification behavior in LBR severe accident.

• Journal of Conservation Science
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• v.27 no.4
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• pp.403-414
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• 2011

This study is re-creational experiment of Goryeo gold-painted decoration based on the research of the gold remaining and gold painting technique on the two pieces of Goryeo gold-painted celadon and the three pieces of Chinese gold-painted porcelain on North Song period which ones have been owned by National Museum of Korea since 2007. For the observation of glue state and color developing ability, four kinds of agglutinative agent and gold powder were mixed over the porcelain sherds, then gradually fired from $100^{\circ}C$ to $1200^{\circ}C$. Visual effect and ideal temperature were measured. Among of them, oil and glue showed the best results in glue state and color developing ability. Through those results, the entire Goryeo engraved celadon were reproduced in modern facilities. Oil and glue were gold-painted over the glaze then it was fired at the ideal temperature 700 to $800^{\circ}C$. For observation the binding condition, the gold-painting cross section was looked by the scanning electron microscope (SEM). As the result, oil and glue did not make much difference in Agglutinative agent, but gold was good, the color developing ability, however, in the case of oil, the edge of gold is curled because of its interfacial tension, and it is not dried well at room temperature so the working property is not as good as the glue. Glue more effective in terms of work efficiency, but color developing ability to fall slightly in this experiment were able to see through.