• Geophysics and Geophysical Exploration
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• v.27 no.2
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• pp.119-128
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• 2024

Marine magnetic surveys provide a rapid and cost-effective method for pioneer geophysical survey for many purposes. Sea-surface magnetometers offer high accuracy but are limited to measuring the scalar total magnetic field and require dedicated cruise missions. Shipboard three-component magnetometers, on the other hand, can collect vector three components and applicable to any cruise missions. However, correcting for the ship's magnetic field, particularly viscous magnetization, still remains a challenge. This study proposes a new additional correction method for ship's viscous magnetization effect in vector data acquired by shipboard three-component magnetometer. This method utilizes magnetic data collected simultaneously with a sea-surface magnetometer providing total magnetic field measurements. Our method significantly reduces deviations between the two datasets, resulting in corrected vector anomalies with errors as low as 7-25 nT. These tiny errors are possibly caused by the vector magnetic anomaly and its related viscous magnetization. This method is expected to significantly improve the accuracy of shipborne magnetic surveys by providing corrected vector components. This will enhance magnetic interpretations and might be useful for understanding plate tectonics, geological structures, hydrothermal deposits, and more.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.65-70
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• 2008

Asphalt concrete pavements are susceptible to deformation and failure compared to cement concrete pavements. Epoxy is commonly used to enhance the bonding and durability of structures. Based on this concept, an epoxy and ceramics combined mixture was developed and applied to the field to estimate the pavement performance, Laboratory and field performance tests were conducted to observe the applicability of epoxy and ceramics composite materials compared to the conventional one. In this research, the epoxy and ceramics composite mixturewas used in two ways. 7 mm and 15 mm of thin surface layers using the mixture were constructed on cement and asphalt concrete pavements, respectively, after surface treatment. 12 months of field performance surveys were conducted to observe the resistances to the crack and deformation. According to the field performance tests, epoxy and ceramics combined mixture showed better bonding and field performances than the conventional one.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.894-896
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• 2003

Koh Chang Island is located near the east border of Thailand. The government of Thailand promotes the island as a model of eco-tourism spots. The Island undeveloped until recent years, is expected to change to major tourist attraction. 'Digital Koh Chang project' has thus. The main objective of this project is to monitor the environment and land use status of the island and to support its sound development. In March 2003, a field survey of this project was planned and field data were collected using both airborne and ground platforms and an ocean vessel. These data were combined with satellite data in the laboratory. This presentation is all balloon-born system field operation. A 5-meter length balloon filled with Helium gas was used, whose payload consisted of two RGB standard color digital still cameras, two directional rotating servo motors, a camera mount cradle as well as signal transmitting and receiving components. A series of aerial high-resolution digital images were rather easily obtained using this inexpensive system, making it possible to monitor intended landscape features in a specific field. Design of simple, low-cost and easily transportable flying platforms and local field surveys using them are useful for getting local ground truth data to calibrate satellite or airborne-based RS data. The design analysis to upgrade the system is further investigated.

• Journal of The Korean Astronomical Society
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• v.49 no.1
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• pp.37-44
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• 2016

The Korea Microlensing Telescope Network (KMTNet) is a wide-field photometric system installed by the Korea Astronomy and Space Science Institute (KASI). Here, we present the overall technical specifications of the KMTNet observation system, test observation results, data transfer and image processing procedure, and finally, the KMTNet science programs. The system consists of three 1.6 m wide-field optical telescopes equipped with mosaic CCD cameras of 18k by 18k pixels. Each telescope provides a 2.0 by 2.0 square degree field of view. We have finished installing all three telescopes and cameras sequentially at the Cerro-Tololo Inter-American Observatory (CTIO) in Chile, the South African Astronomical Observatory (SAAO) in South Africa, and the Siding Spring Observatory (SSO) in Australia. This network of telescopes, which is spread over three different continents at a similar latitude of about -30 degrees, enables 24-hour continuous monitoring of targets observable in the Southern Hemisphere. The test observations showed good image quality that meets the seeing requirement of less than 1.0 arcsec in I-band. All of the observation data are transferred to the KMTNet data center at KASI via the international network communication and are processed with the KMTNet data pipeline. The primary scientific goal of the KMTNet is to discover numerous extrasolar planets toward the Galactic bulge by using the gravitational microlensing technique, especially earth-mass planets in the habitable zone. During the non-bulge season, the system is used for wide-field photometric survey science on supernovae, asteroids, and external galaxies.

• Atmosphere
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• v.21 no.3
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• pp.319-336
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• 2011

The objective of this study was to assess the meteorological capability of Korea by comparing with that of the U.S. and Japan as of 2010. The research was conducted based on various indices and surveys, and quantified the results using the Gordon's scoring model. The index assessment used 11 items derived from 9 segments - surface observation, advanced observation and observations quality in the observation field; data assimilation, numerical model and infrastructure in the data processing field; forecast accuracy in the forecast field; climate prediction and climate change in the climate field - in this research, we classified the meteorological technology into four fields. In the survey assessment, another 10 items in addition to the above 11 ones (total 21 items) were used. In the field of climate, Korea was found to lag far behind the U.S. (96.5p) and Japan (90.5p) with 77.6 points out of 100, which is 18.9 and 12.9 points lower than them respectively. On the other hand, Korea showed the narrowest gap with Japan (95.3p) and the U.S. (94.2) in the forecasting field, recording 90.3 points. Particularly, in surface observation, infrastructure and forecast accuracy segment, Korea was on a par with the U.S. and Japan, boasting 100.5 percent compared to their counterparts. However, in advanced observation, data quality and climate change segment, Korea was only at the level of 81.5 percent compared to that of the U.S. and Japan. All in all, the technological prowess of Korea, scoring 84.6 points, stood at 89.7 percent of that of the U.S. (94.3p) and 91.9 percent of Japan (92.1p).

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.413-424
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• 2014

Objectives: The purpose of this study was to seek measures for improvement and management of farm work safety and health by conducting questionnaire surveys and on-site investigations to ascertain the present state of occurrence of safety accidents and safety and health management levels among swine farmers. In particular, the purpose of this study is to provide basic data for the establishment of measures for the management of safety and health suitable to the characteristics of related working environments. Methods: Questionnaire surveys were conducted among 223 farmers engaged in swine farming in 14 regions, and 10 farms were visited in order to implement multilateral methods, including in-depth interviews, along with field surveys. Results: The surveys indicated that 26.2% of all respondents experienced farm-work related safety accidents and body-reaction related accidents showed a high ratio at 31.1% of all respondents. With regard to cause materials of safety accidents, work other than that directly related to swine raising showed high ratios of safety accidents, with pigsty facility related accidents at 26.6%. Although most workers recognized the dangers latent in the working environments, their behavior and responses to the prevention of safety accidents were still insufficient due to a lack of understanding of safety and health management. In the survey on the present state of personal hygiene and wearing of protective equipment, workers were found to have been exposed to dangerous and harmful environments both inside and outside pigsties, but the actual states of their wearing protective safety equipment were very poor. Conclusion: Given the results of this study, swine farmers well recognize problems in their control of safety accidents and management of safety and health, but their knowledge about safety and health education and management guidelines was insufficient. Therefore, safety and health education, public relations, and customized personal protective equipment suitable for swine raising work should be developed in order to address the foregoing problem.

• Korean Journal of Heritage: History & Science
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• v.52 no.3
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• pp.4-37
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• 2019

Buncheong Ware, which was produced for approximately 200 years from the end of the Goryeo Dynasty to the beginning of the Joseon Dynasty, was used for royal house and state affairs during the early Joseon Dynasty. Records of Buncheong Ware can be found with Jagiso and Dogiso, considered the place of production, in the 'Sejongsylrok jiliji'. This is notable, unlike celadon and white porcelain. However, compared to Gyeongsangnam-do and Gyeongsangbuk-do, the study of Jagiso and Dogiso in Jeollanam-do and Jeollabuk-do has been unsatisfactory. In this paper, we examined the locations of Jagiso and Dogiso in the Jeollanam-do prefecture. This study is focused on Najumok, located in the western part of Jeollanam-do. The following research results were obtained: First, the locations of Jagiso and Dogiso in nine areas were examined. These nine areas comprised Najumok and its immediate provinces of Haejingun, Yeongamgun, Yeonggwanggun, Hampyeonghyeon, Muanhyeon, Gochanghyeon, Heungdeokhyeon and Jangseonghyeon. Previous research results exist for some of the regions; however, only Buncheong Ware was used to estimate Jagiso and Dogiso. In this paper, we tried to discover a more accurate position of Jagiso and Dogiso through a comparison of the place names recorded in the 'Sejongsylrok jiliji' and the place names recorded in the 'Hoguchoungsu'. Also, pottery-related area names and Buncheong Ware obtained from the field survey were reviewed. Table 2 shows the specific positions of Jagiso and Dogiso in the areas examined. Second, it would appear that pottery was produced not only in Jagiso but also in Dogiso. This is because much of Buncheong Ware was unearthed in Najumok, Yeongamgun, and Muanhyeon Dogiso. However, it was only excavated from the Buncheong Kiln Site in Yucheon Village, Sangweol-ri, Yeongam-gun; there could be limitations regarding to the rest of the areas because only a field survey was conducted, not an excavation. A recent excavation at Donggok Village in Cheongdo-ri, Gimje also confirmed a Buncheong Kiln Site. There were two Buncheong Ware ('公', '上') artifacts excavated from the site, believed to be Gongnapjagi. In addition, Cheongdo-ri, where the Buncheong Kiln Site is located, was found to be an area in Wurimgokmyeon, a former Wurimgok at a Dogiso in Jeonjubu. Consequently, it would seem that Dogiso also produced porcelain (Buncheong Ware). If more data can be obtained from the excavations at sites considered to be Dogiso, the results of Dogiso-related research will be strengthened. Third, in previous surveys, field surveys and excavation surveys were based on estimates using artifacts, but the name of the location of the Jagiso and Dogiso may be confirmed more accurately by tracking the changes in the names of the administrative areas. Therefore, although it is important to conduct research using the results of surveys or excavations, changes in the place names or places related to porcelain must not be overlooked.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.3
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• pp.153-179
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• 2022

The purpose of this study, was to examine and understand the possibility of introducing a standard field training semester system and the possibility of operating an autonomous field training semester system that can be operated without payment and propose a response strategy based on their perception survey conducted with the field training institutions. As a result of the study, first, it is apparent that the practice institution shows a very low perception of operating hours and operating methods, including the allocation of job-related training hours. Second, the introduction status of standard field practice turned out to be very low, while the introduction status of standard field practice, operation and agreement, change of standard field practice, specific details of standard field practice contract, and satisfaction of standard field practice turned out to be very low. Based on which, this study considers the introduction of standard field practice based on the reference research including surveys, such as the amendments of the relevan laws, adoption of standard field practice semesters or autonomous field practice semesters, securing and sharing sufficient field practice manuals, among others.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.1-8
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• 2003

Velocity data were acquired at a series of stations in the chordwise direction above a delta wing with leading edge extension, using a triple axis hot film anemometry. Surveys normal to planform yield velocity field data at incidence angle of 24$^{\circ}$and 32$^{\circ}$at a centerline chord Reynolds number of $1.76{\times}10^6$. Experimental results of velocity measurements of mean velocity of three components gave a confidence to quantitative investigate the vortical flow field over a LEX-delta wing with this probe. The present experiments indicated the existence of both wing and LEX vortex where the local mean axial velocity is maximum. It also shown the development of secondary vortex of opposite sign of rotating above the wing surface near the leading edge. The insertion of probe across the flow field was found to have little influence on the position of the vortex core.

• The Journal of Korean Medicine
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• v.20 no.1 s.37
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• pp.30-43
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• 1999

This is a fundamental study for bibliometric analysis investigating the general, research, copyright activities and cited literature related to the field of Oriental Medicine, The data used for this study included theses published by the Journal of Korean Oriental Medicine Society over a period of nine years, from 1990 to 1998, We investigated the productivity of national authors, distribution of cited literature and subject analysis about Oriental Medicine and its authors quantitatively, So we were able to reach several conclusions: 1. The rule of Lotka is applied considerably to analyze the productivity of authors in the field of Oriental Medicine, When it comes to the analysis of national authors it was found that most authors in this field of study published 2 to 10 volumes, likewise other studies. And the rate of co-authorships was high, because most surveys are clinical. 2. When it comes to distribution of cited literatures, independent volumes were cited more than journals. This represents that the citing style of Oriental Medicine has a tendency to follow the methodology of historical research. 3. Scholars in the field of Oriental Medicine mainly tend to cite self-subjects among cited literatures. After analysing self-subjects in this field, the result is that the order of frequency used as cited literatures is as follows: Internal Medicine, Herbology and Oriental Prescription, Acupuncture & Moxibustion. Acupuncture point, and subjects with the circulatory system diseases were mainly cited as far as subordinary subjects of Internal Medicine.