• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.101-108
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• 2019

Background: To date, a variety of surgical approaches have been used to reconstruct the medial orbital wall fracture. Still however, there is still a controversy as to their applicability because of postoperative scars, injury of anatomical structures and limited visual fields. The purpose of this study was to introduce a useful additional medial subbrow approach for better reduction and securement more accurate implant pocket of medial orbital wall fracture with the subciliary technique. Methods: We had performed our technique for a total of 14 patients with medial orbital wall fracture at our medical institution between January 2016 and July 2017. All fractures were operated through subciliary technique combined with the additional medial subbrow approach. They underwent subciliary approach accompanied by medial wall dissection using a Louisville elevator through the slit incision of the medial subbrow procedure. This facilitated visualization of the medial wall fracture site and helped to ensure a more accurate pocket for implant insertion. Results: Postoperative outcomes showed sufficient coverage without displacement. Twelve cases of preoperative diplopia improved to two cases of postoperative diplopia. More than 2 mm enophthalmos was 14 cases preoperatively, improving to 0 case postoperatively. Without damage such as major vessels or extraocular muscles, enophthalmos was corrected and there was no restriction of eyeball motion. Conclusion: Our ancillary procedure was useful in dissecting the medial wall, and it was a safe method as to cause no significant complications in our clinical series. Also, there is an only nonvisible postoperative scar. Therefore, it is a recommendable surgical modality for medial orbital wall fracture.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.6
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• pp.263-269
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• 2018

Changes in water depth caused by underwater earthquakes and landslides cause sea surface undulations, which in turn propagate to the coast and result in significant damage as wave heights normally increase due to the wave shoaling process. Various types of numerical models have been developed to simulate the generation and propagation of tsunami waves. Most of tsunami models determine the initial surface of the water based on the assumption that the movement of the seabed is immediately and identically transmitted to the sea surface. However, this approach does not take into account the characteristics of underwater earthquakes that occur with time history and spatial variation. Thus, such an incomplete description on the initial generation of tsunami waves is totally reflected in the error during the simulation. In this study, the analytical solution proposed by Hammack (1973) was applied in the tsunami model in order to simulate the generation of initial water surface elevation by the change of water depth with time history and its propagation. The developed solution is expected to identify the relationship among various type of seabed motions, initial surface undulations, and wave speeds of elevated water surfaces.

• Journal of The Korean Society For Urban Railway
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• v.6 no.4
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• pp.327-337
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• 2018

Since the track of the ballastless steel plate girder bridge is connected to a main girder without a deck and a ballast, the impact generated by train passage is transferred directly to bridge main members, and it can cause frequent damage of the bridge as well as higher noise and vibration level. Applying the CWR (Continuously Welded Rail) technology can reduce this structural problems, and, to this end, it is necessary to understand the characteristics of factors influencing vehicle-track or track-bridge interaction. In this paper, experimental study results are presented for examining the longitudinal resistance characteristics of the track, including a rail fastener, a sleeper fastener, and a track skeleton, installed on a ballastless steel plate girder bridge. The experiment is conducted using a disposed bridge from service, which is transported to a laboratory. The experimental results show that the rail fastener satisfies the performance criteria of the longitudinal resistance presented in KRS TR 0014-15, and the longitudinal resistance of old and new type sleeper fasteners is higher than the values provided in the existing research. Also, the unloaded longitudinal resistance of the ballastless track is between the ballast and the concrete tracks.

• Journal of Aerospace System Engineering
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• v.15 no.3
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• pp.45-56
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• 2021

Demand for UAM (Urban Air Mobility) aircraft is rapidly increasing in countries around the world due to the problem of traffic congestion in urban areas. Through research and development, various e-VTOL aircraft concepts are being prepared for commercialization, for which airworthiness certification is required, since it is a manned transportation mode for people to board. Factors that pose a fatal threat to the safe operation of UAM aircraft include lightning strikes that can cause damage to structures and disturb the navigation system, as well as icing that impairs flight stability. Since the current UAM aircraft-related lightning and icing certification technology development is insufficient, there is need to develop appropriate airworthiness certification guidelines. In this study, after analyzing the laws and regulations related to aircraft by the FAA and the EASA, we tried to incorporate the lightning and icing certification guidelines for the UAM aircraft. We also analyzed the effects of lightning and icing on UAM aircraft using computational simulation, and presented the basis for establishing practical guidelines for the certification of UAM aircraft to be adopted in the future.

• Journal of Forest and Environmental Science
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• v.37 no.1
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• pp.52-61
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• 2021

Decay fungi can decompose plant debris to recycle carbon in the ecosystem. Still, they can also be fungal pathogens, which can damage living trees and/or wood material and cause a large amount of timber loss. We isolated and identified basidiomycetous fungi from the decayed bark of Mongolian oak wrapped with sticky roll traps. The degrading enzyme activities were then tested for all fungal isolates. The decay ability of selected isolates was assessed based on the weight loss of wood discs after inoculating with culture suspension of decay fungi under the different humidity levels. A total of 46 basidiomycetous fungal isolates belonged to 12 species, and 10 genera were obtained from Jong Myo (16 isolates), Chang Kyung palace (7 isolates), Cheong Gye (10 isolates), and Gun Po (13 isolates). Gymnopus luxurians was the most dominant fungus in the present study, and this species distributed in all survey sites with 9 isolates in Jong Myo, followed by 3 isolates in Chang Kyung palace, while Cheong Gye and Gun Po had only 1 isolate each. Among 46 isolates, 44 isolates secreted at least one enzyme, while 25 isolates produced both cellulase and phenol oxidase enzymes, and 2 isolates produced neither. The assessment of decay ability by artificial inoculation indicated that the weight loss of wood discs was significantly influenced by humidity conditions when inoculated with bark decay fungi. The percent weight losses by G. luxurians inoculation in RH of 90-100% and RH of 65-75% were 4.61% and 2.45%, respectively. The weight loss caused by Abortiporus biennis were 6.67% and 0.46% in RH of 90-100% and RH of 45-55%, respectively. The humidity reduction approach should be applied for further studies to control the growth and spread of bark decay fungi on the trunks wrapped with sticky roll traps.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.327-334
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• 2020

Oxidative stress is common cause of neurodegenerative diseases. The purpose of this study is to investigate the in vitro free radical scavenging activity and protective effect of three Glycyrrhiza species including Glycyrrhiza uralensis, G. glabra, and a new variety of Glycyrrihza (Shinwongam, SW) against hydrogen peroxide-induced oxidative stress in C6 glial cells. In vitro assays, radical scavenging activities of G. uralensis, G. glabra, and SW against 2,2-diphenyl-1-picrylhydrazyl, ·OH, and O2- increased as concentration-dependent manner. In addition, the SW was found to contain the highest polyphenol and flavonoid contents. The treatment of H2O2 to C6 glial cell induced oxidative stress, whereas G. uralensis, G. glabra, and SW significantly increased the cell viability as dose-dependent manner. In particular, SW exerted stronger protective effect on H2O2-induced cytotoxicity, than G. uralensis and G. glabra. Furthermore, reactive oxygen species (ROS) formation was significantly elevated by H2O2 in C6 glial cells. However, treatments of G. uralensis, G. glabra, and SW decreased ROS formation. In addition, SW decreased pro-inflammatory related protein expression levels such as inducible nitric oxide synthase and cyclooxygenase-2, compared to H2O2-treated control group. These results indicated that G. uralensis and G. glavra, especially SW, may be useful for preventing from oxidative stress-induced neuronal damage by regulating inflammatory reaction.

• Journal of Cadastre & Land InformatiX
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• v.50 no.2
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• pp.221-235
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• 2020

The development and utilization of underground spaces are increasing as the use of land based on ground surface became limited due to rapid urbanization triggered by population growth and industrialization. Despite its merit of efficient use of limited land and space, it may contribute to occurrence of various disasters such as sinkholes and damage to underground facilities. After the sinkholes formed and occurred across the country in 2014, there has been an effort to establish Underground Space Integration Map containing 15 types of underground information. Still, there is an increasing demand to improve the quality of underground information stemmed from continuation of such events including the rupture of the hot water pipe in Goyang-si and the fire in the KT site in Ahyeon-dong, Seoul. Hereby, with the aim to improve the quality of Underground Space Integration Map, this study analyzes quality standards, regulations, and guidelines related to spatial data to improve quality inspection standards and methods included in the production rules for the Underground Space Integration Map. In particular, it suggests improvement plan for data quality management for pipe-type underground facilities, known as lifelines, which are essential part of daily life of the citizens, and the largest cause for accidents according to 15 types of underground information managed through the Underground Space Integration Map.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.6
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• pp.37-47
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• 2005

Recently, the malicious e-mail worm-viruses have been widely spreaded over the Internet. If the recipient opens the e-mail attachment or an e-mail itself that contains the worm-virus, the worm-virus can be activated and then cause a tremendous damage to the system by propagating itself to everyone on the mailing list in the user's e-mail package. In this paper, we have designed and implemented two methods blocking e-mail worm-viruses. In the fist method, each e-mail is transmitted only by sender activity such as the click of button on a mail client application. In the second one, we insert the two modules into the sender side, where the one module transforms a recipient's address depending on a predefined rule only in time of pushing button and the other converts the address reversely with the former module whenever an e-mail is sent. The lader method also supports a polymorphism model in order to cope with the new types of e-mail worm-virus attacks. The two methods are designed not to work for the e-mail viruses. There is no additional fraction on the receiver's side of the e-mail system. Experimental results show that the proposed methods can screen the e-mail worm-viruses efficiently with a low overhead.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.589-602
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• 2020

As can be seen in many earthquakes, liquefaction causes differential settlement, which sometimes produces serious damages such as building destruction and ground subsidence. There are many possible active faults near the Busan city and the Yangsan, Dongrae, and Ilgwang faults among them pass through the city. The Busan city is also located within the influence of recent earthquakes, which occurred in the Gyeongju, Pohang, and Kumamoto (Japan). Along the wide fault valleys in the city, the Quaternary unconsolidated alluvial sediments are thickly accumulated, and the reclaimed lands with beach sediments are widely distributed in the coastal area. A large earthquake near or in the Busan city is thus expected to cause major damage due to liquefaction in urban areas. This study conducted an assessment of the liquefaction hazard according to seismic recurrence intervals across the Busan city. As a result, although there are slight differences in degree depending on seismic recurrence intervals, it is predicted that the liquefaction potential is very high in the areas of the Nakdonggang Estuary, Busan Bay, Suyeong Bay, and Songjeong Station. In addition, it is shown that the shorter the seismic recurrence interval, the greater difference the liquefaction potential depending on site periods.

• Smart Media Journal
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• v.9 no.4
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• pp.81-90
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• 2020

Due to the recent economic development and the improvement of income level in China, the desire for quality medical services is increasing compared to the past. As an alternative to satisfy these needs, various applications using smart phones and the like are being developed. The new corona that occurred in December 2019 began to show great interest in non-face-to-face telemedicine services using smart phones due to the worldwide spread of the coronavirus. Therefore, in this study, a total of 200 people were surveyed on the top three mobile medical applications in China, and the data of 120 people who actually used medical applications were analyzed based on Venkatesh's UTAUT2 theory. A study was conducted on the intent to use and the factors affecting the in-law behavior. First, it has become clear that the interactive characteristics, expectations for effort, price value, interest in privacy, habits, and promotional conditions have a positive impact on the user's use. Second, it was investigated that the user's intention to use influences the behavior of use, and among the intentions of use, it was found that the mobilization characteristic expectation, hedonistic motivation, price value, habits, and promotion conditions affect the use behavior. Third, a study result was derived that the controlling variables such as gender, age, school age, and annual income do not affect the user's intention to use mobile medical applications as a controlling variable. Finally, due to the nature of mobile devices that use the Internet, various security vulnerabilities exist, and this can cause great damage or personal and social impact. Therefore, for the development of mobile medical services in China, it is necessary to re-establish a research model through comprehensive and in-depth considerations to supplement these problems in the future.