• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1505-1514
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• 2022

Image matching is a crucial preprocessing step for effective utilization of multi-temporal and multi-sensor very high resolution (VHR) satellite images. Deep learning (DL) method which is attracting widespread interest has proven to be an efficient approach to measure the similarity between image pairs in quick and accurate manner by extracting complex and detailed features from satellite images. However, Image matching of VHR satellite images remains challenging due to limitations of DL models in which the results are depending on the quantity and quality of training dataset, as well as the difficulty of creating training dataset with VHR satellite images. Therefore, this study examines the feasibility of DL-based method in matching pair extraction which is the most time-consuming process during image registration. This paper also aims to analyze factors that affect the accuracy based on the configuration of training dataset, when developing training dataset from existing multi-sensor VHR image database with bias for DL-based image matching. For this purpose, the generated training dataset were composed of correct matching pairs and incorrect matching pairs by assigning true and false labels to image pairs extracted using a grid-based Scale Invariant Feature Transform (SIFT) algorithm for a total of 12 multi-temporal and multi-sensor VHR images. The Siamese convolutional neural network (SCNN), proposed for matching pair extraction on constructed training dataset, proceeds with model learning and measures similarities by passing two images in parallel to the two identical convolutional neural network structures. The results from this study confirm that data acquired from VHR satellite image database can be used as DL training dataset and indicate the potential to improve efficiency of the matching process by appropriate configuration of multi-sensor images. DL-based image matching techniques using multi-sensor VHR satellite images are expected to replace existing manual-based feature extraction methods based on its stable performance, thus further develop into an integrated DL-based image registration framework.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.497-510
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• 2022

Agricultural reservoirs are essential structures for water supplies during dry period in the Korean peninsula, where water resources are temporally unequally distributed. For efficient water management, systematic and effective monitoring of medium-small reservoirs is required. Synthetic Aperture Radar (SAR) provides a way for continuous monitoring of those, with its capability of all-weather observation. This study aims to evaluate the applicability of SAR in monitoring medium-small reservoirs using Sentinel-1 (10 m resolution) and Capella X-SAR (1 m resolution), at Chari (CR), Galjeon (GJ), Dwitgol (DG) reservoirs located in Ulsan, Korea. Water detected results applying Z fuzzy function-based threshold (Z-thresh) and Chan-vese (CV), an object detection-based segmentation algorithm, are quantitatively evaluated using UAV-detected water boundary (UWB). Accuracy metrics from Z-thresh were 0.87, 0.89, 0.77 (at CR, GJ, DG, respectively) using Sentinel-1 and 0.78, 0.72, 0.81 using Capella, and improvements were observed when CV was applied (Sentinel-1: 0.94, 0.89, 0.84, Capella: 0.92, 0.89, 0.93). Boundaries of the waterbody detected from Capella agreed relatively well with UWB; however, false- and un-detections occurred from speckle noises, due to its high resolution. When masked with optical sensor-based supplementary images, improvements up to 13% were observed. More effective water resource management is expected to be possible with continuous monitoring of available water quantity, when more accurate and precise SAR-based water detection technique is developed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.2
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• pp.63-77
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• 2022

Our aim was to reduce estimation errors of a wind velocity model used as an early warning system for weather risk management in the agricultural sector. The Rural Development Administration (RDA) agricultural weather observation network's wind velocity data and its corresponding estimated data from January to December 2020 were used to calculate linear regression equations (Y = aX + b). In each linear regression, the wind estimation error at 87 points and eight time slots per day (00:00, 03:00, 06:00, 09.00, 12.00, 15.00, 18.00, and 21:00) is the dependent variable (Y), while the estimated wind velocity is the independent variable (X). When the correlation coefficient exceeded 0.5, the regression equation was used as the wind velocity correction equation. In contrast, when the correlation coefficient was less than 0.5, the mean error (ME) at the corresponding points and time slots was substituted as the correction value instead of the regression equation. To enable the use of wind velocity model at a national scale, a distribution map with a grid resolution of 250 m was created. This objective was achieved b y performing a spatial interpolation with an inverse distance weighted (IDW) technique using the regression coefficients (a and b), the correlation coefficient (R), and the ME values for the 87 points and eight time slots. Interpolated grid values for 13 weather observation points in rural areas were then extracted. The wind velocity estimation errors for 13 points from January to December 2019 were corrected and compared with the system's values. After correction, the mean ME of the wind velocities reduced from 0.68 m/s to 0.45 m/s, while the mean RMSE reduced from 1.30 m/s to 1.05 m/s. In conclusion, the system's wind velocities were overestimated across all time slots; however, after the correction model was applied, the overestimation reduced in all time slots, except for 15:00. The ME and RMSE improved b y 33% and 19.2%, respectively. In our system, the warning for wind damage risk to crops is driven by the daily maximum wind speed derived from the daily mean wind speed obtained eight times per day. This approach is expected to reduce false alarms within the context of strong wind risk, by reducing the overestimation of wind velocities.

• (The) Research of the performance art and culture
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• no.43
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• pp.145-172
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• 2021

Shin Myung-soon's is based on the taboo 'bombing of the Han River Bridge'. The reality of the bombing of the Han River Bridge in 1950 and the shooting of Colonel Choi Chang-sik was known only as a word of mouth. At that time, the ruling class did not want to reveal the painful mistakes of the unfavorable war situation in the early days of the war and the false broadcasting of the president. The truth of the case, which was kept completely secret even to the bereaved family, could only be revealed after the regime change. After that, the bereaved family of Colonel Choi Chang-sik confirmed the innocence of the deceased through a request for retrial, and then the was born. However, the fate of was not so smooth. At the time, the performance officials vividly remember the difficulties they had with the text. Despite passing the pre-screening of the script, the performance was canceled just before the performance. The fact that the National Theater, officials from the Ministry of Culture and Education, and even military generals visited the practice room to stop the performance, on the contrary, was a testimony to the dangers of . It can be summarized as a crack in official history and a move to stop it. was later adapted into a special TV drama in 1981 and was first released to the public. This was a very meaningful step in terms of dealing with politically sensitive subjects on television, but the inconsistency of in the first place has largely disappeared. After that, in 1988, only after democracy entered the phase of appeasement, could be performed in its full form. In short, can be said to be an example of a process in which the history of the Korean War recorded from the standpoint of an established order and the counter-memory that crack it up are transformed according to the changes of the times and media.

• Annals of Clinical Microbiology
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• v.22 no.1
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• pp.9-13
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• 2019

Background: The isolation of carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly common. Continuous surveillance for these organisms is essential because their infections are closely related to outbreaks of illness and are associated with high mortality rates. The aim of this study was to develop and evaluate multiplex PCR as a means of detecting several important CPE genes simultaneously. Methods: We aimed to develop a multiplex PCR that could detect seven CPE genes simultaneously. The multiplex PCR was composed of seven primer sets for the detection of KPC, IMP, VIM, NDM-1, GES, OXA-23, and OXA-48. We designed different PCR product sizes of at least 100 bp. We evaluated the performance of this new test using 69 CPE-positive clinical isolates. Also, we confirmed the specificity to rule out false-positive reactions by using 71 carbapenem-susceptible clinical strains. Results: A total of 69 CPE clinical isolates showed positive results and were correctly identified as KPC (N=14), IMP (N=13), OXA-23 (N=12), OXA-48 (N=11), VIM (N=9), GES (N=5), and NDM (N=5) by the multiplex PCR. All 71 carbapenem-susceptible clinical isolates, including Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, showed negative results. Conclusion: This multiplex PCR can detect seven CPE genes at a time and will be useful in clinical laboratories.

• Journal of Korean Historical Folklife
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• no.33
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• pp.31-72
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• 2010

At first, I extract materials on folk religion from four encyclopedic literatures of late Chosun dynasty-Lee, Ji-Bong-Ryu-Seol(『芝峯類說』) by Soo-Kwang(李晬光), San-Lim-Kyung-Jae(『山林經濟』) by Hong, Man-Sun(洪萬選), Sung-Ho-Sa-Seol(『星湖僿說』) by Lee-Ik(李瀷), O-Ju-Yeon-Moon-Jang-Jun-San-Go(『五洲衍文長箋散稿』) by Lee, Kyu-Kyung(李圭景), and present these materials by tables. Second, I examined the contents and characters of these materials on folk religion. The conclusions from this research are as follows. ① There are common features and points of difference between these four encyclopedic literatures. One of common features are that all these four are encyclopedic works, but San-Lim-Kyung-Jae is more practical than another three. ② These encyclopedic literatures regard folk religion as a negative culture, because these literatures based on Confucianism. But they did not deny miraculous virtues of folk religion. ③ These encyclopedic literatures give us many informations on gods and spirits of Korean folk religion, i.e. city gods(城隍神)·Yup-Sin(업신)·spirits of disease, god Kim-Bu(金傅大王神)·god Jung-Duk-Yang(鄭得揚)·god of King Kuan-u(關王神)·god Bu-keun(付根神) etc. So I review these gods and spirits referenced in encyclopedic literatures. ④ These encyclopedic literatures show much interest in ghost in common. The reason of interest is that authors of these encyclopedic literatures are all scholars of Sung Confucianism and Sung Confucian was concern about ghost. The Sung Confucianism denied the ghost as personal being whom Korean folk religion regards to a kind of spirits. Instead of beliefs in ghost of folk religion, they insist on the ghost as Ki(氣), a kind of cosmic principle. But these encyclopedic literatures acknowledge some parts of folk religion's beliefs in ghost, because they admit the miraculous virtues of these parts. ⑤ There are many items on divination in these encyclopedic literatures. But they show dual attitude on divinations. The one is negative attitude to divinations on individual destiny and the other one is positive attitude to divinations on agriculture. ⑥ There are also many items on witchcrafts in these encyclopedic literatures. Through these items, I assumed pervasiveness of beliefs on witchcraft at that time. ⑦ Shamans, as religious specialist, are stand on a central position of Korean folk religion. So it is a matter of course that these encyclopedic literatures concerned on Korean shaman. As Confucians, authors of these encyclopedic literatures did not regards shamans as positive one. But they did not deny miraculous virtues of shamans. In spite of these encyclopedic literatures have negative view points to, and include false informations Korean folk religion, I would like to emphasis on importance of these encyclopedic literatures to understand Korean folk religions, especially Korean folk religions of late Yi Dynasty.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1353-1369
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• 2023

In the event of a disaster accident at sea, the scale of damage will vary due to weather effects such as wind, currents, and tidal waves, and it is obligatory to minimize the scale of damage by establishing appropriate control plans through quick on-site identification. In particular, it is difficult to identify pollutants that exist in a thin film at sea surface due to their relatively low viscosity and surface tension among pollutants discharged into the sea. Therefore, this study aims to develop an algorithm to detect suspended pollutants on the sea surface in RGB images using imaging equipment that can be easily used in the field, and to evaluate the performance of the algorithm using input data obtained from actual waters. The developed algorithm uses image enhancement techniques to improve the contrast between the intensity values of pollutants and general sea surfaces, and through histogram analysis, the background threshold is found,suspended solids other than pollutants are removed, and finally pollutants are classified. In this study, a real sea test using substitute materials was performed to evaluate the performance of the developed algorithm, and most of the suspended marine pollutants were detected, but the false detection area occurred in places with strong waves. However, the detection results are about three times better than the detection method using a single threshold in the existing algorithm. Through the results of this R&D, it is expected to be useful for on-site control response activities by detecting suspended marine pollutants that were difficult to identify with the naked eye at existing sites.

• Journal of the Korean Society of Radiology
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• v.81 no.4
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• pp.886-898
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• 2020

Purpose The purpose of our study was to evaluate digital breast tomosynthesis as a breast cancer screening modality for women with gynecologic cancer. Materials and Methods This retrospective study included patients with underlying gynecologic malignancies who underwent screening digital breast tomosynthesis for breast cancer. The cancer detection rate, recall rate, sensitivity, specificity, and positive predictive value (PPV) were calculated. PPV1 was defined as the percentage of all positive screening exams that have a tissue diagnosis of cancer within a year. PPV2 was defined as the percentage of all diagnostic exams (and Breast Imaging Reporting and Data System category 4, 5 from screening setting) with a recommendation for tissue diagnosis that have cancer within a year. PPV3 was defined as the percentage of all known biopsies actually performed that resulted in a tissue diagnosis of cancer within the year. For each case of screen-detected cancer, we analyzed the age, type of underlying gynecologic malignancy, breast density, imaging features, final Breast Imaging Reporting and Data System assessment, histologic type, T and N stages, molecular subtype, and Ki-67 index. Results Among 508 patients, 7 with breast cancer were identified after a positive result. The cancer detection rate was 13.8 per 1000 screening exams, and the recall rate was 17.9%. The sensitivity was 100%, and the specificity was 83.2%. The false negative rate was 0 per 1000 exams. The PPV1, PPV2, and PPV3 were 7.7, 31.8, and 31.8, respectively. Conclusion Digital breast tomosynthesis may be a promising breast cancer screening modality for women with gynecologic cancer, based on the high cancer detection rate, high sensitivity, high PPV, and high detection rate of early-stage cancer observed in our study.

• Journal of Korea Water Resources Association
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• v.57 no.3
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• pp.181-193
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• 2024

The increasing atmospheric imbalance caused by climate change leads to an elevation in precipitation, resulting in a heightened frequency of flooding. Consequently, there is a growing need for technology to detect and monitor these occurrences, especially as the frequency of flooding events rises. To minimize flood damage, continuous monitoring is essential, and flood areas can be detected by the Synthetic Aperture Radar (SAR) imagery, which is not affected by climate conditions. The observed data undergoes a preprocessing step, utilizing a median filter to reduce noise. Classification techniques were employed to classify water bodies and non-water bodies, with the aim of evaluating the effectiveness of each method in flood detection. In this study, the Otsu method and Support Vector Machine (SVM) technique were utilized for the classification of water bodies and non-water bodies. The overall performance of the models was assessed using a Confusion Matrix. The suitability of flood detection was evaluated by comparing the Otsu method, an optimal threshold-based classifier, with SVM, a machine learning technique that minimizes misclassifications through training. The Otsu method demonstrated suitability in delineating boundaries between water and non-water bodies but exhibited a higher rate of misclassifications due to the influence of mixed substances. Conversely, the use of SVM resulted in a lower false positive rate and proved less sensitive to mixed substances. Consequently, SVM exhibited higher accuracy under conditions excluding flooding. While the Otsu method showed slightly higher accuracy in flood conditions compared to SVM, the difference in accuracy was less than 5% (Otsu: 0.93, SVM: 0.90). However, in pre-flooding and post-flooding conditions, the accuracy difference was more than 15%, indicating that SVM is more suitable for water body and flood detection (Otsu: 0.77, SVM: 0.92). Based on the findings of this study, it is anticipated that more accurate detection of water bodies and floods could contribute to minimizing flood-related damages and losses.

• Sim-seong Yeon-gu
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• v.25 no.2
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• pp.194-223
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• 2010

I tried here to interpret german fairy tale "Three Dogs" from the aspect of analytical psychology. A poor young shepherd will be 'hero'accidently while wandering the world to find good luck. When he was exhausted and frustrated in wandering life, a stranger appeared before him. A stranger offered barter. So he exchanged three sheep with three black dogs which a stranger had. One dog can bring the food. Another dog can tear everything. The last one can break even steel and iron. After that, shepherd led a satisfactory wandering life. On the way, he met a sad princess who should sacrifice herself for the piece of the country to the dragon which swallows a young girl yearly. But the strong black dog which tears everything, killed the dragon and saved the princess from the sacrifice. After that, a young shepherd promised princess to come back to her after three years of wandering life. In the meanwhile a horse driver played hero false. But the princess couldn't reveal the truth because of the threat of horse driver. Three years later, the young shepherd appeared in the castle. But the true hero was caught in the prison and finally cried out the strongest dog and succeeded in escaping from the prison. And with help of another dog which bring food to him, he could meet the princess and finally married her. So they lived happy life for a long time. But he remembered the poor younger sister. So he wanted to live together with her. After that, three dogs left him with saying, they stayed to see whether he shares his good fortune with his younger sister. Then they turned into birds and disappeared in the air. In this fairy tale can we find many important symbols. With the amplification of symbols and the interpretation of this fairy tale in terms of Jung's analytical psychology, I tried to find the meaning of individuation process in this fairy tale. Hero kills the dragon which could symbolize negative mother archetype. After overcoming the negative mother complex, he could get princess which could be expressive of Anima. This marriage could symbolize coniunctio oppositorum, an important process in individuation. Each fairy tale tells us the individuation process in a different way. And the fairy tale works always in our mind with plain, simple, pure, crystal like nature. Through it can we take precious treasure like wisdom for life.