• Journal of the Korean Geophysical Society
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• v.2 no.1
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• pp.27-38
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• 1999

The errors between track segments or at the cross-over points of shipborne gravity were successfully reduced by applying a cross-over error adjustment technique using satellite gravity. The integration of shipborne and satellite altimeter-implied free-air gravity anomalies after the cross-over error adjustment resulted in a high resolution gravity map which contains both short and long wavelength components. The successful adjustment of the cross-over errors in the shipborne gravity using the satellite gravity suggests that the shipborne gravity can be combined with the satellite anomalies characterized by a stable and long wavelength component. The resulting free-air anomaly map is evenly harmonized with both short and long wavelength anomalies. Thus the corrected anomaly map can be better used for the geological interpretation. Free-air anomalies with more than 140 mGal in total variations generally correspond to the seafloor topographic changes in their regional patterns. A series of gravity highs are aligned from the Korea Plateau to the Oki Island, which are interpreted to be caused by seamounts or volcanic topographies. The gravity minima along the western and southern shelf edge are associated not only with the local basement morphology and thick sediment fill at the continental margin, but also possibly with the crustal edge effect known for passive continental margins. Series of NE-trending linear anomalies are possibly caused by a swarm of volcanic intrusions followed the initial opening of the Ulleung Basin. The linear high anomalies in the Ulleung Plateau are terminated by the straightly NNW-trending anomalies with a sharp gradient in its western boundary which indicates a fault-line scarp. The opposite side adjoined with the fault-line scarp shows no correlation with the fault-line scarp in geometry indicating that the block might be horizontally slided from the north. A gravity high in contrast to the deepening in seafloor toward the northeastern central Ulleung Basin is probably responsible for the thin crust and shallow seated mantle. The gravity minima along the western and southern shelf edge are associated not only with the local basement morphology and thick sediment fill at the continental margin, but also possibly with the crustal edge effect known for passive continental margins. Series of NE-trending linear anomalies are possibly caused by a swarm of volcanic intrusions followed the initial opening of the Ulleung Basin. The linear high anomalies in the Ulleung Plateau are terminated by the straightly NNW-trending anomalies with a sharp gradient in its western boundary which indicates a fault-line scarp. The opposite side adjoined with the fault-line scarp shows no correlation with the fault-line scarp in geometry indicating that the block might be horizontally slided from the north. A gravity high in contrast to the deepening in seafloor toward the northeastern central Ulleung Basin is probably suggestive of a thin crust and shallow seated mantle.

• 한국지구물리탐사학회:학술대회논문집
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• 2002.09a
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• pp.24-45
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• 2002

For the last several decades, high-resolution shallow marine seismic technique has been used for various resources, engineering and geological surveys. Even though the multichannel method is powerful to image subsurface structures, single channel analog survey has been more frequently employed in shallow water exploration, because it is more expedient and economical. To improve the quality of the high-resolution seismic data economically, we acquired digital seismic data using a small air gun, 6 channel streamer and PC-based system, performed data processing and produced high-resolution seismic sections. For many years, such test acquisitions were performed with other studies which have different purposes in the area of off Pohang, Yellow Sea and Gyeonggi-bay. Basic data processing was applied to the acquired data and the processing sequence included gain recovery, deconvolution, filtering, normal moveout, static corrections, CMP gathering and stacking. Examples of digitally processed sections were shown and compared with analog sections. Digital seismic sections have a much higher resolution after data processing. The results of acquisition and processing show that the high-resolution shallow marine seismic surveys using a small air gun, 6 channel streamer and PC-based system may be an effective way to image shallow subsurface structures precisely.

• Geophysics and Geophysical Exploration
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• v.15 no.1
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• pp.39-46
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• 2012

Recently, stratigraphic reservoirs are getting more attention than structural reservoirs which have mostly developed. However, recognizing stratigraphic thin gas reservoirs in a stacked section is usually difficult because of tuning effects. Moreover, if the reflections from the brine-saturated region of a thin layer have the same polarity with those from the gas-saturated region, we could not easily identify the gas reservoir with conventional data processing technique. In this study, we introduced a way to delineate the gas-saturated region in a thin layer reservoir using a spectral decomposition method. First of all, amplitude spectrum with the variation of the frequency and the incident angle was investigated for the medium which represents property of Class 3, Class 1 or Class 4 AVO response. The results show that the maximum difference in the amplitude spectra between brine and gas-saturated thin layers occurs around the peak frequency independent of the incident angle and the type of AVO responses. In addition, the amplitude spectra of the gas-saturated zone are greater than those of brine-saturated one in Class 3 and Class 4 at the peak frequency while those of phenomenon occur oppositely in Class 1. Based on the results, we applied spectral decomposition method to the stacked section in order to distinguish the gas-saturated zone from the brine-saturated zone in a thin layer reservoir. To verify our new method, we constructed a thin-layer velocity model which contains both gas and brine-saturated zones which have the same reflection polarities. As a result, in the spectral decomposed sections near the peak frequency obtained by Wigner-Ville Distribution (WVD), we could identify the difference between reflections from gas- and brinesaturated region in the thin layer reservoir, which was hardly distinguishable in the stacked section.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.37.1-37
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• 1981

Even through the methods of improving hearing are widely practiced in Korea, with its 30 years of history, there are many different opinions regarding the selection of surgical technique and the materials to be used in tympanoplasty. Also there are varying standards of postoperative evaluations. Therefore, we have done research to evaluate hearing improvement which in one of the objective of the middle ear surgery. The research was conducted for one year, January to December 1980. This research compared the level of hearing improvement after tympanoplasty, according to materials used in tympanoplasty and collumelization. Following are the data we have obtained; 1) Total number of cases we have reviewed were 306. Out of this, 35% of the cases were tympanoplasty type 1, 12.7% of the cases were collumelization with mastoidectomy, and 11.9% of the cases received collumelization without mastoidectomy. 2) We have conducted audiometry on 41.1% of the tympanoplasty type 1, 64.1% of the collumelization with mastoidectomy, and 45.7% of the collumelization without mastoidectomy. 3) We have observed above 11 dB hearing improvement in 70% of the tympanoplasty type 1, 36% of the collumelization with mastoidectomy, and 44% of the collumelization without mastoidectomy. 4) Over 11 dB decrease of air-bone gap in 61% of the tympanoplasty type 1,32% of the collumelization with mastoidectomy, and 63% of the collumelization without mastoidectomy. 5) If we look at the hearing improvement according to the materials used in the tympanoplasty, there was above 11 dB improvement of the air conduction in 63% with cartilage and 54% with fascia. In air-bone gap, 56% with cartilage and 52% with fascia. 6) If we look at the hearing improvement according to the materials used in the collumelization, there was above 11 dB improvement in 50% with cartilage, 14% with homograft, 55% with autograft. In air-bone gap, 56%, 21%, and 55% respectively.

• Journal of Korea Water Resources Association
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• v.51 no.9
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• pp.827-837
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• 2018

The stabilities of sliding and overturning of caisson and bearing capacity of mound against eccentric and inclined loads, which possibly happen to a composite caisson breakwaters, have been analyzed by using the technique of multiple failure modes. In deterministic approach, mathematical functions have been first derived from the ultimate limit state equations. Using those functions, the minimum cross section of caisson can straightforwardly be evaluated. By taking a look into some various deterministic analyses, it has been found that the conflict between failure modes can be occurred, such that the stability of bearing capacity of mound decreased as the stability of sliding increased. Therefore, the multiple failure modes for the composite caisson breakwaters should be taken into account simultaneously even in the process of deterministically evaluating the design cross section of caisson. Meanwhile, the reliability analyses on multiple failure modes have been implemented to the cross section determined by the sliding failure mode. It has been shown that the system failure probabilities of the composite breakwater are very behaved differently according to the variation of incident waves. The failure probabilities of system tend also to increase as the crest freeboards of caisson are heightening. The similar behaviors are taken place in cases that the water depths above mound are deepening. Finally, the results of the first-order modal are quite coincided with those of the second-order modal in all conditions of numerical tests performed in this paper. However, the second-order modal have had higher accuracy than the first-order modal. This is mainly due to that some correlations between failure modes can be properly incorporated in the second-order modal. Nevertheless, the first-order modal can also be easily used only when one of failure probabilities among multiple failure modes is extremely larger than others.

• Journal of Life Science
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• v.17 no.10
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• pp.1309-1314
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• 2007

Investigation on health conditions of Thai koi (Anabas testudineus) were carried out through clinical and histopathological observations from different farms of Mymensingh district for seven months during August 2006 to February 2007. Fish sampling and water quality parameters (temperature, dissolved oxygen and pH) were monitored on a monthly basis. Clinical examination of fishes was also carried out for any kind of abnormalities at monthly intervals. Samples of skin, muscle, gill, liver and kidney were observed by histological technique. Among the water quality parameters the values of water temperature, dissolved oxygen were found to be at unfavorable level for fish during the colder months in the farms. Clinically it was observed that fishes were more affected from December to January and almost normal in appearance during August to September and February. Different clinical symptoms like scale loss, dermal lesion, ulcer and loss of caudal fin were noticed in December and January. In histopathological study, structures of fish organs were normal from August to September. In the months of October and November, minor pathologies were found to be started. Marked pathological changes like necrosis, pyknosis, inflammation, hemorrhage, hypertrophy, hyperplasia, missing of primary and secondary gill lamellae were observed in the months of December and January. Whereas, in the month of February the pathological condition of fish gradually reduced. Again when considered individual fish farm, fishes of Reliance Aqua Farm were more affected than Sotota Matshya Hatchery. The study showed that severity of clinical and pathological changes were increased in December and January. During the period EUS and protozoan diseases were noticed in A. testudineus of the investigated farms.

• Journal of Life Science
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• v.27 no.12
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• pp.1445-1451
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• 2017

Mitochondria play a central role in energy generation by using electron transport coupled with oxidative phosphorylation. They also participate in other important cellular functions including metabolism, apoptosis, signaling, and reactive oxygen species production. Therefore, mitochondrial dysfunction is known to contribute to a variety of human diseases. Furthermore, there are various inherited diseases of energy metabolism due to mitochondrial DNA (mtDNA) mutations. Unfortunately, therapeutic options for these inherited mtDNA diseases are extremely limited. In this regard, mitochondrial replacement techniques are taking on increased importance in developing a clinical approach to inherited mtDNA diseases. In this study, green fluorescence protein (GFP)-tagged mitochondria were isolated by differential centrifugation from a mammalian cell line. Using microinjection technique, the isolated GFP-tagged mitochondria were then transferred to bovine oocytes that were triggered for early development. During the early developmental period from bovine oocytes to blastocysts, the transferred mitochondria were observed using fluorescent microscopy. The microinjected mitochondria were dispersed rapidly into the cytoplasm of oocytes and were passed down to subsequent cells of 2-cell, 4-cell, 8-cell, morula, and blastocyst stages. Together, these results demonstrate a successful in vitro transfer of isolated mitochondria to oocytes and provide a model for mitochondrial replacement implicated in inherited mtDNA diseases and animal cloning.

• Journal of Korean Home Economics Education Association
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• v.32 no.1
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• pp.107-125
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• 2020

The purpose of this study was to analyze the dietary life units of Korean and American high school home economics textbook according to Habermas's three systems of action and to find out how the three systems of action are reflected in the learning objectives and activity tasks of the textbook. To achieve this purpose, this study analyzed the learning objectives and activity tasks of the dietary life units in the textbooks of 'technology & home economics' and 'home economics science' in Korea, and 'succeeding in life and career' in America using a content analysis technique based on Habermas's three systems of action. In analyzing the content, each learning objective or activity was matched with one of the three systems of action by examining the context. In some cases, two or more systems of actions were integrated in one activity. This is a case where a series of learning tasks that involve different action system were grouped into one. The numbers of learning objectives and activities of the units of 'technology & home economics', 'home economics science' textbooks of Korean high schools and 'succeeding in life and career' dietary life of American high schools were 3, 26, and 248, respectively. In Korean textbooks, the percentage of communicative action was highest among the three systems, that is, 66.7% for 'technology & home economics' textbooks and 50% for 'home economics science' textbooks. In comparison technical action was the highest in American textbooks at 66.5%. Activities related to technical action included cooking, conducting research on health and food, or conducting experiments. The activities related to communicative action included role play related to health and table manners, or writing reports after conducting surveys or interviewing professionals. The activities related to emancipative action were to social participation activities such as service project in relation to health and food, or to find problems that occur in dietary life and think about be best solution through practical reasoning.

• Tuberculosis and Respiratory Diseases
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• v.63 no.1
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• pp.59-66
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• 2007

Background: Surgical lung biopsy is required to establish the etiology and stage of interstitial lung disease(ILD). and this procedure can be safe and meaningful for making clinical decisions. We wanted to determine the safety of surgical lung biopsy(SLB) in patients with interstitial lung disease(ILD). Methods: We conducted a retrospective review of 40 patients with suspected ILD and they underwent surgical lung biopsy from January 2001 to June 2006 at Chungnam University Hospital. We analyzed retrospectively according to their age, gender, pulmonary function, chest tube duration, the arterial blood gases, the procedural technique, and the requirement for supplemental oxygen and mechanical ventilation(MV) at the time of SLB. Results: The mean age of the patients was 56.4${\pm}$16.13 years(range: 21 to 77 years). Overall, the 30-day and 90-day mortality rates were 15% and 20%, respectively. The predictors of perioperative mortality were either the need for mechanical ventilation(MV) at the time of SLB or the need for supplemental oxygen prior to undergoing SLB. Among the 32 patients who were 90-day survivors, the proportion of those patients using the oxygen supplement was 28.1% (n=9). All 8 patients who were 90-day non-survivors used oxygen supplement (p=0.000). The use of the MV was 12.5% (n=4) in the 90-day survivors (n=32) and 62.5% (n=5) in the 90-day non-survivors (n=8); there was a significant difference between the 90-day survivors and non-survivors (p=0.000). Conclusion: Patients who require MV and supplemental oxygen are associated with an increased risk for death following SLB.

• Journal of the Korea Concrete Institute
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• v.14 no.1
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• pp.126-135
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• 2002

Plate bonding technique has been widely used in strengthening of existing concrete structures, although it has often a serious problem of premature falure such as interface separation and rip-off. However, this premature failure problem has not been well explored yet especially in view of local failure mechanism around the interface of plate ends. The purpose of the present study is, therefore, to identify the local failure of strengthened plates and to derive a separation criterion at the interface of plates. To this end, a comprehensive experimental program has been set up. The double lap pull-out tests considering pure shear force and half beam tests considering combined flexure-shear force were performed. The main experimental parameters include plate thickness, adhesive thickness, and plate end arrangement. The strains along the longitudinal direction of steel plates have been measured and the shear stress were calculated from those measures strains. The effects of plate thickness, bonded length, and plate end treatment have been also clarified from the present test results. Nonlinear finite element analysis has been performed and compared with test results. The Interface properties are also modeled to present the separation failure behavior of strengthened members. The cracking patterns as well as maximum failure loads agree well with test data. The relation between maximum shear and normal stresses at the interface has been derived to propose a separation failure criterion of strengthened members. The present study allows more realistic analysis and design of externally strengthened flexural member with steel plates.