• 한국해양공학회지
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• 제15권1호
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• pp.36-44
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• 2001

To predict the influence on fish stocks which were caused by environmental change in the fishing ground of shallow sea areas, we have developed the Shallow-Sea Ecological Model(SSEM) which that focuses on living organisms, especially fish and benthos. By applying the SSEM in the Seto-Inland Sea of Japan, we have simulated another aspect of influence on fish stocks that was caused by oxygen deficient water mass and nutrient loads. From the simulated result of the fish stocks, it was indicated that the stock of fish and benthos has shown a relative difference between the western sea and the eastern sea in the Seto-Inland Sea. According the to prediction, results of fish stocks that were caused by oxygen deficient water mass, it was estimated that the pelagicfish stock increases about 6 %, whereas the stocks of demersalfish and benthos decreases about 30% and 70%, respectively. On the other hand, it seemed that there was an increased in the fish stocks of demersalfish and benthos in the eastern sea of Seto-Inland Sea by nutrient loads reduction.

• Ocean and Polar Research
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• 제40권1호
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• pp.1-13
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• 2018

Previous studies have indicated a great regional difference in Sea Level Rise (SLR) in the Pacific and it has been suggested that this is linked to climate variability over the past two decades. In this study, we seek to identify the possible linkage between regional sea level and Pacific climate variability from altimetry-based sea level data (1993-2012) and further investigate how the Pacific sea level has changed spatially and temporally over the past 60 years from long-term sea level reconstruction data (1953-2008). Based on the same method as Zhang and Church (2012), the Inter-annual Climate Index (ICI) associated with the El $Ni{\tilde{n}}o-Southern$ Oscillation (ENSO) and the Decadal Climate Index (DCI) associated with Pacific Decadal Oscillation (PDO) are defined and then the multiple variable linear regression is used to analyze quantitatively the impact of inter-annual and decadal climate variability on the regional sea levels in the Pacific. During the altimeter period, the ICI that represents ENSO influence on inter-annual time scales strongly impacts in a striking east-west "see-saw mode" on sea levels across the tropical Pacific. On the other hand, the decadal sea level pattern that is linked to the DCI has a broad meridional structure that is roughly symmetric in the equator with its North Pacific expression being similar to the PDO, which largely contributes to a positive SLR trend in the western Pacific and a negative trend in the eastern Pacific over the two most recent decades. Using long-term sea level reconstruction data, we found that the Pacific sea levels have fluctuated in the past over inter-annual and decadal time scales and that strong regional differences are presented. Of particular interest is that the SLR reveals a decadal shift and presents an opposite trend before and after the mid-1980s; i.e., a declining (rising) trend in the western (eastern) Pacific before the mid-1980s, followed by a rising (declining) trend from the mid-1980s onward in the western (eastern) Pacific. This result indicates that the recent SLR patterns revealed from the altimeters have been persistent at least since the mid-1980s.

• 한국환경과학회지
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• 제20권7호
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• pp.857-872
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• 2011

The variation of groundwater level in Jeju Island is analyzed with the data of precipitation observed from 48 monitoring post and groundwater level observed from 84 monitoring wells during 2001 to 2009. The groundwater level rises in summer and falls in winter. The rise of groundwater level by precipitation is fast and small in the eastern region and slow and large in the western region. However, the speed of fall during the period of no rain is slower in the eastern region than in the western region. It tells that permeability is greater in the eastern region than in the western region. In this paper, we set up the base level of groundwater and calculate recharge volume between the base level and groundwater surface. During the period, the average recharge volume was $9.83{\times}10^9m^3$ and the maximum recharge volume was $2.667{\times}10^{10}m^3$ after the typhoon Nari. With these volume and the recharge masses obtained by applying the recharge ratio of 46.1%, estimated by Jeju Province (2003), the porous ratio over the whole Jeju Island is 16.8% in average and 4.6% in the case of maximum recharge volume just after typhoon Nari. A large difference in the two ratios is because that it takes time for groundwater permeated through the ground just after rain fall to fill up the empty porous part. Although the porous ratios over the whole Jeju Island obtained in this way has a large error, they give us the advantage to roughly estimate the amount of recharged groundwater mass directly from observing the groundwater level.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• 제25권1호
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• pp.1-13
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• 1997

This paper presents a precise geoid (PNU95 Geoid) over the southern half of the Korean peninsula. The geoid using the OSU91A reference gravity model to degree and order of 167 with an integration radius of 27 km fits to the well-distributed 71 GPS data best. The RMS difference between the modeled geoid and the GPS/leveling-implied geoid is 0.15 m, and its accuracy with respect to the GPS/leveling distance is 1.1 ppm. The resulting PNU95 Geoid varies from 21.8 m at the western part of the peninsula, Kanghwa-Do, to 30.2 m at the south-eastern part. Kyungju, generally increasing eastward.

• 대한원격탐사학회지
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• 제38권4호
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• pp.365-374
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• 2022

Mining activity causes environmental pollution and geological hazards such as ground subsidence or landslide of which continuous monitoring is necessary. In this study, the activity on the Fushun West Open-Pit Mine (FWOPM), one of the largest open-pit coal mines in Asia located in Fushun, Liaoning Province, China, was analyzed by using a time-series Sentinel-1 InSAR coherence dataset. By using the difference between the two Digital Elevation Models (DEM) of the area, it was possible to confirm that there was a stockpiling activity in the western area of the FWOPM while excavation activity in the eastern area. By using RGB composite images using the yearly-averaged InSAR coherence images, the activity of the mine was confirmed by period, which was confirmed by Google Earth optical images. As a result, it was possible to confirm three landslides and the related activities on the northwest slope and the dumping activity on the west slope of FWOPM.

• 항공우주의학회지
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• 제30권2호
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• pp.75-79
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• 2020

This study focuses on the comparative and quantitative analysis of the epidemiologic trends and aspects of severe fever with thrombocytopenia syndrome (SFTS) outbreaks between Korea and Japan from 2013 to 2017. The following factors were analyzed; cumulative incidence rate (CIR), cases-fatality rate (CFR), and the epidemic aspects, including cases related to gender, male-to-female morbidity ratio (MFMR), age, seasonal, and geographical distributions. We observed 607 SFTS cases with CIR in Korea during the period 2013 to 2017 were as 0.24 per 100,000 populations and with a 127 fatal-cases (F.C.s), corresponding to a CFR of 20.9%, respectively. During the same period in Japan, 319 SFTS cases with a CIR of 0.05 and with 60 F.C.s to a CFR of 18.8% observed. When compared, the CIR of SFTS in Korea was significantly higher than in Japan (P<0.01), but there were no significant differences levels of the CFR and MFMR between Korea and Japan. Also, a higher incidence of SFTS was observed in people aged over 50-years or elders in Korea and those of 60-years or elders in Japan (P<0.01). The seasonal distribution of SFTS outbreak cases showed that the incidence in summer through autumn in Korea (92.4% of total cases) was higher than in Japan (65.2%), while the outbreaks of SFTS in spring was much higher in Japan (31.0%) than in Korea (7.4%), (P<0.01). The regional distribution revealed no significant difference between the eastern area (44.8%) and the western area (46.8%) of the Korean peninsula except Jeju-island (8.4%). However, in Japan, the incidence only occurred in Chubu-Kinki-Chugoku (30.3%), Shikoku (25.7%), Kyushu (42.6%) and Okinawa (0.3%), which are the western and southern areas of Japan. These differences in SFTS occurrence may reflect the influences of vector/hosts, climate, and geographical and cultural characteristics between the two countries.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.864-867
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• 2006

Thermal infrared images of Landsat-5 TM and Landsat-7 ETM+ sensors have been unrivalled sources of high resolution thermal remote sensing (60m for ETM+, 120m for TM) for more than two decades. Atmospheric effect that degrades the accuracy of Sea Surface Temperature (SST) measurement significantly, however, can not be corrected as the sensors have only one thermal channel. Recently, MODIS sensor onboard Terra satellite is equipped with dual-thermal channels (31 and 32) of which the difference of at-satellite brightness temperature can provide atmospheric correction with 1km resolution. In this study we corrected the atmospheric effect of Landsat SST by using MODIS data obtained almost simultaneously. As a case study, we produced the Landsat SST near the eastern and western coast of Korea. Then we have obtained Terra/MODIS image of the same area taken approximately 30 minutes later. Atmospheric correction term was calculated by the difference between the MODIS SST (Level 2) and the SST calculated from a single channel (31 of Level 1B). This term with 1km resolution was used for Landsat SST atmospheric correction. Comparison of in situ SST measurements and the corrected Landsat SSTs has shown a significant improvement in $R^2$ from 0.6229 to 0.7779. It is shown that the combination of the high resolution Landsat SST and the Terra/MODIS atmospheric correction can be a routine data production scheme for the thermal remote sensing of ocean.

• 한방재활의학과학회지
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• 제23권3호
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• pp.125-132
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• 2013

Objectives The purpose of this study was to compare the effects of acupuncture treatment with those of collaborative treatment regarding acute Bell's palsy. Methods Twenty-six patients who received outpatient treatment between March 2012 and February 2013 were divided into 2 groups. The East-West treatment group (EW group, n=12) received prednisolone and then acupuncture afterwards. The Eastern treatment group (E group, n=14) received just acupuncture. Acupuncture was administered 3 to 4 times a week, and both groups were educated to practice facial muscle exercises at home. Evaluations were made before treatment, after 1 week, 2 weeks, and 3 weeks using the House-Brackmann facial nerve grading system. Results Compared to before treatment, the House-Brackmann grades of both EW and E groups after 1, 2 and 3 weeks of treatment significantly decreased (p<0.05). Regarding group comparison, the House-Brackmann grade of the EW group was significantly lower than the E group at 1 week (p=0.043), but there was no significant difference at 2 and 3 weeks. Regarding improvement of House-Brackmann grades, there was no significant difference between the two groups at 1, 2 and 3 weeks (p>0.05). Conclusions Compared to just acupuncture treatment, collaborative treatment with prednisolone significantly improved the House-Brackmann grade after 1 week, but there was no difference as time passed. Because early intervention determines the prognosis of Bell's palsy, collaborative treatment at the early stage will be clinically helpful to patients.

• International Journal of Contents
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• 제16권4호
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• pp.84-97
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• 2020

Since national image video advertisements are a means of public relations with wide delivery and major repercussions at home and abroad, this study performs a comparative analysis of video advertisements aired by previous governments as reported by Daejung Kim, Moohyun Roh, Myungbak Lee, and Geunhye Park. The characteristics of the previous governments, whether or not social trends were reflected, and the importance of traditional and modern elements were examined. As we describe, there are clear differences in video advertisements by government regime, and while messages expressing traditional values of Eastern culture have gradually decreased, reflecting the trends of the times, the messages emphasizing the modern values of the West have gradually increased. Our research confirmed that traditional elements such as 'Samulnori' and 'Taekwondo' are gradually disappearing. In addition, it was confirmed that the collective values, traditional values, and humanism represented by the 'large crowd' and 'traditional elements' in the Kim Dae-jung and Roh Moo-hyun administration changed in the Lee Myung-bak and Park Geun-hye administrations to more individualistic, materialistic, Western values. This study is meaningful in that it analyzed the components and characteristics of national image advertisements by governments in the past, how social trends were reflected, and the weight difference between traditional and modern elements. Based on this research, the significance of the current Moon Jae-in government's groundwork for follow-up research should not be understated.

• 해양환경안전학회지
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• 제5권1호
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• pp.19-27
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• 1999

This paper is to estimate the long and short term variations of mean sea level in Korean coastal waters by identifying interrelations among the mean sea level, atmospheric pressure and air temperature along the coast. For this, long-term tidal data observed at tidal and weather observation stations were brought into a statistical analysis. It was noted that, in a general sense, an inverse relationship exists between the sea level and the atmospheric pressure and a positive relationship between the sea level and air temperature, respectively. The maximum difference of monthly mean sea level was in the range of 21 to 25 cm at the eastern and southeastern coasts, meanwhile more than 30 cm being in both in southern and western coasts. It was also noted that mean sea level continues to rise in a long-term basis. Long-term variation of mean sea level trends to rise 0.10 ∼ 0.44 cm per year for each region. However, the long-term variation of mean sea level in the isolated islands shows a different trend, Ullngdo being 0.41 cm fall per year and Chejudo being 0.44 cm rise per year.