• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.54.2-54.2
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• 2021

Galaxy clusters are the largest structures in the universe located at the top of the cosmological hierarchical model, so the evolution of the universe can be understood by studying clusters of galaxies. Therefore, finding a larger number of galaxy clusters plays an important role in exploring how the universe evolves. A large number of catalogs for galaxy clusters in the northern sky have been published; however, there are few catalogs in the southern sky due to the lack of wide sky survey data. KMTNet Synoptic Survey of Southern Sky(KS4) project, which observes a wide area of the southern sky about 7000 deg² with KMTNet telescopes for two years, is in progress under the SNU Astronomy Research Center. We use the KS4 multi-wavelength optical data and measure photometric redshifts of galaxies for finding galaxy clusters at redshift z<1. Currently, the KS4 project has observed approximately 33% of the target region, and a pipeline that measures photometric redshifts of galaxies has been created. When the project is completed, we expect to find more than a hundred thousand galaxy clusters, and this will improve the study of galaxy clusters in the southern sky.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.68.2-68.2
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• 2021

Galaxy clusters are the largest structures in the universe located at the top of the cosmological hierarchical model, so the evolution of the universe can be understood by studying clusters of galaxies. Therefore, finding a larger number of galaxy clusters plays an important role in exploring how the universe evolves. A large number of catalogs for galaxy clusters in the northern sky have been published; however, there are few catalogs in the southern sky due to the lack of wide sky survey data. KMTNet Synoptic Survey of Southern Sky(KS4) project, which observes a wide area of the southern sky about 7000 deg² with KMTNet telescopes for two years, is in progress under the SNU Astronomy Research Center. We use the KS4 multi-wavelength optical data and measure photometric redshifts of galaxies for finding galaxy clusters at redshift z<1. Currently, the KS4 project has observed approximately 50% of the target region, and a pipeline that measures photometric redshifts of galaxies has been created. When the project is completed, we expect to find more than a hundred thousand galaxy clusters, and this will improve the study of galaxy clusters in the southern sky.

• Radiation Oncology Journal
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• v.29 no.3
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• pp.147-155
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• 2011

Purpose: This study was designed to determine the influencing factors and clinical course of pathologically proven cases of radiation-induced brain injury (RIBI). Materials and Methods: The pathologic records of twelve patients were reviewed; these patients underwent surgery following radiotherapy due to disease progression found by follow-up imaging. However, they were finally diagnosed with RIBI. All patients had been treated with 3-dimensional conventional fractionated radiotherapy and/or radiosurgery for primary or metastatic brain tumors with or without chemotherapy. The histological distribution was as follows: two falx meningioma, six glioblastoma multiform (GBM), two anaplastic oligodendroglioma, one low grade oligodendroglioma, and one small cell lung cancer with brain metastasis. Results: Radiation necrosis was noted in eight patients and the remaining four were diagnosed with radiation change. Gender (p = 0.061) and biologically equivalent dose $(BED)_3$ (p = 0.084) were the only marginally influencing factors of radiation necrosis. Median time to RIBI was 7.3 months (range, 0.5 to 61 months). Three prolonged survivors with GBM were observed. In the subgroup analysis of high grade gliomas, RIBI that developed <6 months after radiotherapy was associated with inferior overall survival rates compared to cases of RIBI that occurred ${\geq}6$ months (p = 0.085). Conclusion: Our study demonstrated that RIBI could occur in early periods after conventional fractionated brain radiotherapy within normal tolerable dose ranges. Studies with a larger number of patients are required to identify the strong influencing factors for RIBI development.

• Anxiety and mood
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• v.18 no.2
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• pp.101-108
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• 2022

Objective : The purpose of this study was to investigate depression, anxiety, trauma experience, and suicidal tendency among patients who were hospitalized in a community treatment center and to identify the factors that were associated with each symptom. Methods : A total of 213 patients who were hospitalized in the Tae-reung community treatment center between March 16, 2020 and April 30, 2020 were recruited into this study. A self-report questionnaire or interview by mental health professionals was used to assess PHQ-2, GAD-7, PC-PTSC and P4 screener. In 90 patients who completed the survey, multiple regression modeling was conducted to identify the burden of each psychiatric symptoms and associated demographic characteristics. Results : Female gender was significantly positively associated with GAD-7 score, score of each GAD-7 subscale of 1, 2, 3 or 4 (nervous, control of worry, worry, and trouble relaxing), and sum of GAD-7 subscale scores reflecting cognitive and emotional experience of anxiety (1. nervous+2. control of worry+3. worry+7. afraid). Previous psychiatric history and, number of counseling service used were significantly positively associated with the PHQ-2 score and the duration of isolation was significantly negatively associated with the PHQ-2 score. Conclusion : These results showed that depression and anxiety symptoms were more prevalent in COVID-19 patients at the community treatment center than in the general population. Among the demographic characteristics, female gender was positively associated with cognitive and emotional experience of anxiety. It shows the necessity of an appropriate psychiatric intervention protocol and health-policy preparation for community treatment centers.

• Proceedings of the Korean Vacuum Society Conference
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• 2003.02a
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• pp.85-85
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• 2003

• Gut and Liver
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• v.13 no.1
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• pp.5-6
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• 2019

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.117.1-117.1
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• 2007

• 한국전기화학회:학술대회논문집
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• 1999.10a
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• pp.6-7
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• 1999

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.115-117
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• 1998

• Proceedings of the Microbiological Society of Korea Conference
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• 1997.04a
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• pp.54.1-54.1
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• 1997