• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.7-17
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• 2005

The determination of seismic velocities in refractors for near-surface seismic refraction investigations is an ill-posed problem. Small variations in the computed time parameters can result in quite large lateral variations in the derived velocities, which are often artefacts of the inversion algorithms. Such artefacts are usually not recognized or corrected with forward modelling. Therefore, if detailed refractor models are sought with model based inversion, then detailed starting models are required. The usual source of artefacts in seismic velocities is irregular refractors. Under most circumstances, the variable migration of the generalized reciprocal method (GRM) is able to accommodate irregular interfaces and generate detailed starting models of the refractor. However, where the very-near-surface environment of the Earth is also irregular, the efficacy of the GRM is reduced, and weathering corrections can be necessary. Standard methods for correcting for surface irregularities are usually not practical where the very-near-surface irregularities are of limited lateral extent. In such circumstances, the GRM smoothing statics method (SSM) is a simple and robust approach, which can facilitate more-accurate estimates of refractor velocities. The GRM SSM generates a smoothing 'statics' correction by subtracting an average of the time-depths computed with a range of XY values from the time-depths computed with a zero XY value (where the XY value is the separation between the receivers used to compute the time-depth). The time-depths to the deeper target refractors do not vary greatly with varying XY values, and therefore an average is much the same as the optimum value. However, the time-depths for the very-near-surface irregularities migrate laterally with increasing XY values and they are substantially reduced with the averaging process. As a result, the time-depth profile averaged over a range of XY values is effectively corrected for the near-surface irregularities. In addition, the time-depths computed with a Bero XY value are the sum of both the near-surface effects and the time-depths to the target refractor. Therefore, their subtraction generates an approximate 'statics' correction, which in turn, is subtracted from the traveltimes The GRM SSM is essentially a smoothing procedure, rather than a deterministic weathering correction approach, and it is most effective with near-surface irregularities of quite limited lateral extent. Model and case studies demonstrate that the GRM SSM substantially improves the reliability in determining detailed seismic velocities in irregular refractors.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.3
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• pp.39-48
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• 2019

This research is based on the analysis of in-depth interviews of designers who participated in the design of the Yeonnam-dong section, which was completed in 2016. The case study site has received many domestic and foreign awards and is receiving very positive reviews from actual users. 53 concepts were derived from the open coding of the ground theory methodology. Thirty-four higher categories incorporated the concepts and 18 higher categories that reintegrated them. Later, the six categories of the ground theory were interpreted as the paradigm, and it was determined that the aspects of 'will of client' and 'work efficiency', 'site resources' and 'field manager's specialty' were the categories that had the greatest positive impact on the park construction. The key category of this park's construction was interpreted as "a park-construction model with active empathy and communication." The results of the study and are linked to the following research proposals. First, the need to improve the trust between the client and the landscape designer and the need to improve the customary administrative procedures; second, the importance of the input of landscape experts into the park construction process; third, the importance of all efforts to develop the design; fourth, the importance of on-site circular resources and landscape preservation; and fifth active social participation to increase the opportunity. This study, which seeks to grasp the facts that existed behind the park's construction, which received excellent internal and external evaluations, and has a qualitative, objective and structural interpretation of the social network related to the park's construction, in contrast to the conventional quantitative post-evaluation. It is expected that the administration and system improvements related to landscaping will be further improved through the continuation of in-depth post-evaluation studies.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.1
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• pp.76-87
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• 2019

The purpose of this study was to evaluate the performance of and to derive future maintenance-management measures of the constructed alternative habitat for the Kaloula borealis at the University of Seoul, examining the period between 2015-2017. The research was constructed in 2014 and in a $191m^2$ area. The performance evaluation was divided into maintaining the habitat of the target species, maintaining the population and reproduction rates of the target species, maintaining the habitat of the wild species, the resilience of natural ecosystems, and the harmony with the surrounding environment. In terms of maintaining the habitat of the target species, soil collected from the existing habitat of the Kaloula borealis and was the depth was increased to 30cm in the alternative habitat. An artificial water supply was required every year during the supporting the spawning and hatching of other amphibians along with the Kaloula borealis. The sources of water of the alternative habitat were both rain and tap water, as it cannot be maintained naturally. Additionally, the Kaloula borealis thrived because it inhabited the research site and the average temperature was $26.2^{\circ}C$ from April-June, which is when the Kaloula borealis spawns. In terms of maintaining the population and reproduction rates of the Kaloula borealis, they were evaluated to have stable rates of reproduction. In terms of maintaining the habitat of the wild species, studies on vegetation and the structure of the characteristics of prey or predators will be needed. Also, alien species, such as Humulus japonicus and Bidens frondosa needed to be removed to maintain the wetland ecosystem of the wild species. In the assessment of the resilience of the natural ecosystems, the mud was monitored, noting the changes in the depth of water, with steps taken to reduce the leakage of water. The mud collected from the Haneul Pond wetland, which is located around the research site was piled up. Also, partial mowing management and the inducement of a natural vegetation colony was required for vegetation management. It was also necessary to create porous spaces, such as old trees and tree branches to create a habitat with hiding places and feeding and spawning places for small organisms. In terms of the harmony with the surrounding environment, the following threat factors needed to be managed: amphibian roadkill by vehicles and pedestrians and artificial draining due to nearby user access. Based on the monitoring results, alternative habitat management measures presented the promoting various waterside structures, in which amphibians can spawn and hide in, managing the water environment consistently, managing the vegetation, focused on the habitat of the wild species, and managing the surrounding environment for the habitat. The creation of an alternative habitat should be managed through monitoring, reflecting the characteristics of the changes in the site. Also continuing efforts are also needed to improve the habitat of the target species.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.543-557
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• 2021

Because aerosols have different spectral characteristics according to the size and composition of the particle and to the satellite sensors, a comparative analysis of aerosol products from various satellite sensors is required. In South Korea, however, a comprehensive study for the comparison of various official satellite AOD (Aerosol Optical Depth) products for a long period is not easily found. In this paper, we aimed to assess the performance of the AOD products from MODIS (Moderate Resolution Imaging Spectroradiometer), VIIRS (Visible Infrared Imaging Radiometer Suite), Himawari-8, and Sentinel-3 by referring to the AERONET (Aerosol Robotic Network) sun photometer observations for the period between January 2015 and December 2019. Seasonal and geographical characteristics of the accuracy of satellite AOD were also analyzed. The MODIS products, which were accumulated for a long time and optimized by the new MAIAC (Multiangle Implementation of Atmospheric Correction) algorithm, showed the best accuracy (CC=0.836) and were followed by the products from VIIRS and Himawari-8. On the other hand, Sentinel-3 AOD did not appear to have a good quality because it was recently launched and not sufficiently optimized yet, according to ESA (European Space Agency). The AOD of MODIS, VIIRS, and Himawari-8 did not show a significant difference in accuracy according to season and to urban vs. non-urban regions, but the mixed pixel problem was partly found in a few coastal regions. Because AOD is an essential component for atmospheric correction, the result of this study can be a reference to the future work for the atmospheric correction for the Korean CAS (Compact Advanced Satellite) series.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.196-209
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• 2022

This study compared and analyzed the spatial division function and role of partitions by comparing the entire space and the spatial changes before and after the installation of partitions in <Donggwoldo>, which was manufactured in the late Joseon Dynasty. As a research method, a set standard was prepared to decompose the space of <Donggwoldo> into a unit space, and the standard was set according to the role and height of the space by classifying it into a main space, sub space, and transition space. Two convex maps were prepared according to before and after the installation of the Panjang, and the values of connectivity, control, and integration, which are spatial syntax variables, were calculated and analyzed. The results of the study are as follows. First, the partition in <Donggwoldo(東闕圖)> did not affect the overall spatial arrangement and control or connection of Donggwol, but the movement and access of space is limited to specific areas. Second, the partition was a facility intensively distributed in Naejeon(內殿) and Donggung(東宮) to be used actively in the way of space utilization. It shows that the unit space increased rapidly due to the installation of the partition. Since the partition was installed in the spaces that were open and under high control in the case of Naejeon(內殿), it helped to secure private spaces as closed ones under low control. On the other hand, for Donggung(東宮), the spaces were compartmented and divided with the partition to guide the movement path through narrow gates of the partition and increase the depth of the space. This helped to create spaces that are free and can be hidden as it increased the number of spaces coming through. Third, In addition to the functions of "eye blocking, space division, and movement path control" revealed in prior research, the partition has created a "space that is easy to control" within a specific area. The installation of the partition reduced the scale through the separation of spaces, but it occurred the expansion of the movement path and space. Also, the partition functioned to strengthen hiding and closure or increase openness as well through space division. This study is significant in that it revealed the value of the spatial control function of panjang through the analysis of spatial control and depth by analyzing the function of the partition with a mathematical model in addition to the analysis and study of the function and role of panjang. In addition, it is valuable in that it has prepared a framework for analysis tools that can be applied to traditional residential complexes similar to palaces by applying space syntax to <Donggungdo> to create convex spaces according to unit space division and connection types of palace architecture and landscape elements.

• Journal of The Korean Association For Science Education
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• v.43 no.2
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• pp.139-150
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• 2023

This study started with the awareness of the need to explore various aspects of science education and was conducted according to the necessity of practical research on science cultural activities targeting adults. Accordingly, adults' book discussions of science fiction were selected as research cases, and science-related attitudes in science cultural activities were explored. There are four participants in the study, all of whom have engaged in a book club and have not majored or are working in science disciplines. Three science fictions were selected after establishing specific standards for the selection discussed with participants. For four months, a total of three unstructured book discussions of science fiction, post-interviews for each discussion, and in-depth individual interviews after the end of the entire activity were conducted. Various data such as recorded and transcribed reading discussion discourse, post- and in-depth individual interviews, researchers' observation records, and participants' book journals were collected and analyzed using a continuous comparison method. As a result of the study, as scientific thinking is illustrated in SF, the participants also demonstrated scientific attitudes during their discussions. In addition, the textual feature(storytelling) of science fiction was found to lessen cognitive overload and the burden of understanding science by providing scientific knowledge with context. Finally they demonstrated a shift in attitude toward science, valuing science cultural activities in themselves, rather than simply viewing science as a subject of understanding and learning. The conclusions and meanings of this study based on the above results are presented to enhance a positive attitude toward science for adults even after school education.

• Journal of Popular Narrative
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• v.25 no.4
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• pp.45-71
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• 2019

Through the expansion of platforms in the media era, this paper notes the phenomenon in which 'high-teen romance drama,' a genre which had been marginalized in the past, began to re-emerge. It analyzes the 'high-teen romance drama,' which is moving from TV to the Web and being produced in various ways, while successfully returning to the TV drama format. This study sums up the latest trends in TV and web-based high-teen romance dramas, and as a case study, this paper examines the characteristics of the 'high-teen romance drama' in relation to the platform's environment through the web drama A-Teen, TV drama 18 Moment. Due to the restriction of ratings, high-teen romance dramas have been one of the largely marginalized genres on television. But in the web space, high-teen romance dramas are no longer non-mainstream. The high-teen romance drama has been solidifying its position through the Web, with absolute support from young viewers. Web dramas are gradually expanding their influence on the genre and subject of TV dramas. The high-teen romance drama is one of the most prominent examples of this trend. The popular interest and success of the high-teen romance web drama has brought the forgotten high-teen romance drama back to TV. The web drama A-Teen is a high-teen romance drama about everyday life and love of high school students, and became one of the most popular and popular web dramas, leading to a Season 2. A-Teen actively utilizes teenage culture and expression, and a strategy that leads to empathy among teenage viewers. In A-Teen, love is recreated in a way that relieves the depth of overconsumption emotions. Instead of dealing in depth with the inner conflict over love, it takes an approach ofpresenting the emotional change of love in real time and forming a consensus with the acceptor. The TV drama 18 Moment is one of the programs that has helped refocus attention to TV-hitting romance dramas. 18 Moment underlines the growth of the characters, with the main characters reaching maturity through love as fresh and innocent teenagers. The TV drama 18 Moment is a high-teen romance drama that has been transformed into a way to apply the web-fadding high-times grammar while retaining the typicality of existing TV hagwons to suit the TV broadcasting environment. As the Internet becomes more ubiquitous, video content is changing based on the newly emerging platforms. Dramas no longer mean just traditional television media. While considering the limitations of TV, this paper analyzed the background of the rebirth of the high-teen romance drama, which had been marginalized, through the web platform. This is meaningful in that it identifies and considers the increasing popularity of this genre of drama.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.365-369
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• 2008

This study analyzed the incidence of wound infection after the operation of mandibular third molar extraction in relation with antibiotic prophylaxis with the object of young and healthy patients. The study object was 1,177 mandibular third molars of 850 men of 20 to 25 years old without any specific systemic disease. Three methods of preventive antibiotic medication were selected according to the preventive antibiotic medication previously reported; three experimental groups were selected based on them, and the antibiotic used was amoxicillin($^{(R)}Kymoxin$, Yuhanyanghaeng, Seoul). The group 1 includes the patients that took the antibiotic orally before the operation(one hour earlier, 500mg) and for three days after the operation(250mg per time, three times/day), the group 2 is the ones that took the same antibiotic orally only once about one hour before the operation(500mg), and the group 3 did not take any antibiotics before and after the operation. And to compare the difficulties and the degrees of extraction during operations which can be possibly related to the wound infection after the operations, the mandibular third molars' impacted depths and extraction methods were investigated as well. To check if the wound was infected, observations with an internal of one week were performed twice after the operation, and the meaningfulness of the infection incidence was verified through Chi-square test using SPSS program(SPSS Inc., IL, USA). There was no statistically significant difference between the antibiotic medication methods and the wound infection incidence after the operation among the experimental groups. As examining the relations between the mandibular third molar operation methods and the wound infection incidence after the operation, there existed a statistically meaningful difference in the infection incidence according to the operation methods(p=0.020). And there was no statistically significant difference in the wound infection incidence according to the impacted depth of the mandibular third molar. Therefore, it is thought that there exists little necessity of prophylatic antibiotics medication when extracting the mandibular third molar of young and healthy men without any systemic disease in general; however, in case when it is expected that the possibility of infection will be high or the wound on the tissue will be severe, it is sure that the prophylactic antibiotics medication will be necessary.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.12 s.138
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• pp.1644-1654
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• 2004

As globalization has been accelerating in recent years, more people have opportunities to live abroad for an extended period of time, which is known to have strong influence on consumers. The main purposes of this study were to examine if and how sojourning experience could bring changes to people in general and in clothing styles with focus on Korean adults. The researchers conducted in-depth interviews on a total of thirty-six women and twenty-one men who lived in foreign countries more than two years and have been back in Korea longer than one year. The major results indicated that in addition to personalities, age, length of stay, activities during stay, gender, and cultural distances played important roles in bringing long-term changes on people. Re-established self-identity, changes in values, and openness toward diversity were major common changes observed in the interviewees. In addition, they became educated consumers with good knowledge of diverse brands and prices, and emphasized value as opposed to price. Changes in clothing styles were noted mainly among women. They placed high importance on having their own style, coordination and appropriateness, which were consistent with the general changes. Influences of different cultures were also noted.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.4
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• pp.23-30
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• 1998

During an earthquake, there are three components of excitation : horizontal excitation of the ground, vertical excitation of the pile due to superstructure feedback produced by vertical excitation of the ground, and the seawater excitation by the vertical ground shaking, that is, "the seaquake." These excitations could have effects on the pore pressure buildup mode induced in the near-field of open-ended pile and the soil plugs in open-ended pipe piles installed at offshore sites. While the ground and pile excitation could be modeled by exciting the soil and pile with simulated motions, seaquake excitation induced by the vertical ground shaking can be modeled by pulsing the water pressure at the seabed. The objectives of this study were to observe buildup trend for the porewater pressures developed in near-field of open-ended pipe pile installed in the calibration chamber during the simulated earthquake and seaquake and, also to confirm the cause for reduction of soil plugging according to pore pressure buildup. During the simulated horizontal seismic motion, there was no upward flow through soil plug because the similar magnitude of excess porewater pressure were occurred at the top and under the toe of soil plug. During the horizontal seismic motion, relatively higher hydraulic gradients caused upward flow in the soil plug and then the degradation of plugging resistance was about 20%. During seaquake, in the case of the open-ended pile installed in a deep sea with more than 220m of water depth, soil plug failed completely because of high upward hydraulic gradients through soil plug.soil plug.