• Title/Summary/Keyword: $In_2S_3$

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THE STUDY ON THE EFFECTS OF THE INSULIN-LIKE GROWTH FACTOR-I ON THE BIOLOGICAL ACTIVITY OF THE HUMAN PERIODONTAL LIGAMENT CELLS (Insulin-like growth factor-I 이 치주인대세포의 생물학적 활성도에 미치는 영향에 대한 연구)

  • Kim, Seong-Jin;Lee, Jae-Mok;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.24 no.2
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    • pp.219-237
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    • 1994
  • The ultimate goal of clinical periodontal therapy is to achieve regeneration of a healthy connective tissue reattachment. Conventional therapy including scaling, root planing, gingival curettage, gingivectomy and flap procedures of various types results primarily in repair rather than regeneration of the periodontium. In order for periodontal regeneration to occur, progenitor periodontal ligament cells must migrate to the denuded root surface, attach to it, proliferate and mature into an organized and functional fibrous attachment apparatus. Polypeptide growth factors belong to a class of potent biologic mediators which regulate cell differentiation, proliferation, migration and metabolism. Insulin-like growth factor-I (IGF- I ) of these factors appear to have an important role in periodontal wound healing and bone formation. The purpose of this study is to evaluate the effects of IGF- I on the periodontal ligament cells to use as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were obtained from periodontal tissue explants culture of the first premolar tooth extracted for the orthodontic treatment. Cells were cultured in Dulbecco's modified Eagle medium(DMEM) with 10% fetal bovine serum. Fourth to seventh passage cells were plated in 24 well tissue culture plates and medium changed to serum-free medium prior to addition of growth factors. Cell proliferation was measured by the incorporation of $[^3H]-thymidine$ into DNA, Protein synthesis was determined by measurement of $[^3H]-proline$ incorporation into collagenase-digestible protein(CDP) and noncollagenous protein(NCP) according to the method of Peterkofsky and Diegelmann (1971), And alkaline phosphatase activity was measured as one parameter of osteoblastic differentiation. The results were as follows : The DNA synthetic activity was increased in a dose-dependent manner with IGF- I except for 0.1ng/ml concentration of IGF- I At the concentration of 10, 100ng/ml, IGF- I significantly increased the DNA synthetic activity(P<0.05) The total protein, collagen and noncollagen synthesis was increased in a dose-dependent manner with IGF- I except for 0.1ng/ml concentration of IGF- I. At the concentration of 1, 10, 100ng/ml, IGF- I significantly increased the total protein, collagen and noncollagen synthesis activity(P<0.95, P<0.001). The % of collagen was not effected according to the concentration of IGF- I. The alkaline phosphatase activity was increased in a dose-, time-dependent manner with IGF- I (10, 100ng/ml). In conclusions, the present study shows that IGF- I has a potentiality to enhance the DNA synthesis of periodontal ligament cells with including the increase of the total protein and collagen synthetic activity. The use of IGF- I to mediate biological stimulation of periodontal ligament cells shows promise for future therapeutic applications.

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Environmental Assessment for Acid Mine Drainage by Past Coal Mining Activities in the Youngwol, Jungseon and Pyungchang areas, Korea (영월, 정선 및 평창지역 폐 석탄광 산성광산배수의 환경오염 평가)

  • 정명채
    • Economic and Environmental Geology
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    • v.36 no.2
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    • pp.111-121
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    • 2003
  • The objective of this study is to investigate the physical and chemical properties for environmental assessment of water system affected by acid mine drainage (AMD) from coal mining activities in the Youngwol, Jungseon and Pyungchang areas in Korea. During November 2000 to July 2002, 6 times of water samples were collected season-ally from acid mine drainage and nearby streams at 13 coal mines in the study area. The physical and chemical properties including pH, Eh, TDS, salinity, bicarbonates and DO were measured in the field. Eighteen cations includ-ing Al, Ca, Fe, Mg, Mn and Zn, and 6 anions including nitrates and sulfates were also analyzed by ICP-AES and If, respectively. Acid water from the Jungam coal mine has typical characteristics of AMD with very low pH(3∼4) and high TDS(1,000∼5,000 mg/1). Relatively high concentrations(mg/kg) of heavy meals, especially for Al(380), Fe(80), Mn(44) and Zn(8), were found in water samples from the Jungam coal mine area. Water samples from the Seojin, Sebang and Sungjin coal mines also contained over 50 mg/l of Al, >100 mg/1 of Fe and )10 mg/1 of Mn. In addition to anioins, over 1,000 mg/l of sulfate was found in several water samples. Seasonally, the concentrations of metals and sulfates varied; wet season samples were relatively higher in metals and sulfates than dry season samples. It is needed to establish the proper remediation and environmental monitoring of the AMD continuously.

Social Network Analysis for the Effective Adoption of Recommender Systems (추천시스템의 효과적 도입을 위한 소셜네트워크 분석)

  • Park, Jong-Hak;Cho, Yoon-Ho
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.305-316
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    • 2011
  • Recommender system is the system which, by using automated information filtering technology, recommends products or services to the customers who are likely to be interested in. Those systems are widely used in many different Web retailers such as Amazon.com, Netfix.com, and CDNow.com. Various recommender systems have been developed. Among them, Collaborative Filtering (CF) has been known as the most successful and commonly used approach. CF identifies customers whose tastes are similar to those of a given customer, and recommends items those customers have liked in the past. Numerous CF algorithms have been developed to increase the performance of recommender systems. However, the relative performances of CF algorithms are known to be domain and data dependent. It is very time-consuming and expensive to implement and launce a CF recommender system, and also the system unsuited for the given domain provides customers with poor quality recommendations that make them easily annoyed. Therefore, predicting in advance whether the performance of CF recommender system is acceptable or not is practically important and needed. In this study, we propose a decision making guideline which helps decide whether CF is adoptable for a given application with certain transaction data characteristics. Several previous studies reported that sparsity, gray sheep, cold-start, coverage, and serendipity could affect the performance of CF, but the theoretical and empirical justification of such factors is lacking. Recently there are many studies paying attention to Social Network Analysis (SNA) as a method to analyze social relationships among people. SNA is a method to measure and visualize the linkage structure and status focusing on interaction among objects within communication group. CF analyzes the similarity among previous ratings or purchases of each customer, finds the relationships among the customers who have similarities, and then uses the relationships for recommendations. Thus CF can be modeled as a social network in which customers are nodes and purchase relationships between customers are links. Under the assumption that SNA could facilitate an exploration of the topological properties of the network structure that are implicit in transaction data for CF recommendations, we focus on density, clustering coefficient, and centralization which are ones of the most commonly used measures to capture topological properties of the social network structure. While network density, expressed as a proportion of the maximum possible number of links, captures the density of the whole network, the clustering coefficient captures the degree to which the overall network contains localized pockets of dense connectivity. Centralization reflects the extent to which connections are concentrated in a small number of nodes rather than distributed equally among all nodes. We explore how these SNA measures affect the performance of CF performance and how they interact to each other. Our experiments used sales transaction data from H department store, one of the well?known department stores in Korea. Total 396 data set were sampled to construct various types of social networks. The dependant variable measuring process consists of three steps; analysis of customer similarities, construction of a social network, and analysis of social network patterns. We used UCINET 6.0 for SNA. The experiments conducted the 3-way ANOVA which employs three SNA measures as dependant variables, and the recommendation accuracy measured by F1-measure as an independent variable. The experiments report that 1) each of three SNA measures affects the recommendation accuracy, 2) the density's effect to the performance overrides those of clustering coefficient and centralization (i.e., CF adoption is not a good decision if the density is low), and 3) however though the density is low, the performance of CF is comparatively good when the clustering coefficient is low. We expect that these experiment results help firms decide whether CF recommender system is adoptable for their business domain with certain transaction data characteristics.

Underweight Related Factors in School-Aged Children in Daegu (대구지역 초등학생의 저체중 현황파악 및 관련요인 분석)

  • Yun, Young-Hee;Park, Kyong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1592-1599
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    • 2013
  • Despite numerous studies regarding overweight or obese children, only a limited number of studies have investigated the effect of underweight. The purpose of this study is to investigate the determinants of underweight among school-aged children. A total of 493 students (86 underweight and 407 normal weight students) aged 11 to 13 years were included in our study. Socio-demographic characteristics, eating habits, health information, self-perception of weight, weight-control efforts and birth-related information were collected by using survey questionnaires for children and parents. Dietary information was obtained by two 24-hour food records, which were completed by both children and their parents. The prevalence of underweight was significantly higher in girls than boys, and the frequency of medical treatment and flu symptoms were higher in underweight children than normal ones. Overall, girls tended to overestimate their own weight; this misclassification was greater among underweight girls. Birthweight was positively correlated with current weight (P<0.05) and height (P<0.01) in girls, but these correlations were not seen in boys. In conclusion, underweight girls had inappropriate self-perception of weight, and underweight in girls may be related with birthweight and inadequate dietary intakes. Therefore, it is important to build a well-designed framework that integrates efforts of home, school, and community to maintain a healthy weight with balanced diet and exercise throughout the lifetime.

Construction of Tomato yellow leaf curl virus Clones for Resistance Assessment in Tomato Plants (토마토 작물의 TYLCV 저항성 평가에 이용할 수 있는 감염성 클론 개발)

  • Choi, Seung Kook;Choi, Hak Soon;Yang, Eun Young;Cho, In Sook;Cho, Jeom Deog;Chung, Bong Nam
    • Horticultural Science & Technology
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    • v.31 no.2
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    • pp.246-254
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    • 2013
  • Five isolates of Tomato yellow leaf curl virus (TYLCV) collected from various regions of Korea were amplified using PCR and determined the sequences of full-length genome, respectively. The PCR-amplified DNA of each TYLCV isolate was introduced into a binary vector to construct infectious clone containing 1.9 copies of the corresponding viral genome. Various cultivars and breeding lines of tomato were inoculated with Agrobacterium tumefaciens harboring infectious clone of each TYLCV isolate to assess resistance against TYLCV. Susceptible cultivar 'Super-sunread' revealed typical yellowing and narrowing of the upper leaves. In contrast, breeding linesTY12, GC9, GC171, and GC173, which contained the TY-1 and/or TY-3 genes that confer resistance against TYLCV in nature, were completely symptomless, suggesting that the lines were resistant to challenging TYLCV isolates. Symptoms of TYLCV in susceptible tomato cultivars are significantly different from those of TYLCV in the resistant tomato cultivars at 30 days after agroinfiltration. Although genomic DNAs of TYLCV were detected from the breeding lines TY12, GC9, GC171, and GC173 using real-time PCR analysis with specific primers, levels of TYLCV DNA accumulation in the resistant breeding lines were much lower than those of TYLCV DNA accumulation in susceptible tomato cultivars. Similar symptom severity and levels of TYLCV DNA accumulation were observed from TYLCV infections mediated by Bemisia tabaci in the resistant and susceptible tomato cultivars. Concentration of agrobacterium did not affect the response of tomato cultivars against TYLCV inoculation. Taken together, these results suggest that TYLCV inoculation via agroinfiltration is as effective as inoculation through Bemisia tabaci and is useful for breeding programs of TYLCV-resistant tomato.

Application of Photosynthetic Pigment Analysis Using a HPLC and CHEMTAX Program to Studies of Phytoplankton Community Composition (HPLC를 이용한 광합성색소 분석과 CHEMTAX 프로그램을 이용한 식물플랑크톤 군집조성 연구)

  • Lee, Yong-Woo;Park, Mi-Ok;Kim, Yoon-Suk;Kim, Seong-Su;Kang, Chang-Keun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.3
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    • pp.117-124
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    • 2011
  • Many studies of the phytoplankton community structure have been conducted using the CHEMTAX program on the basis of the photosynthetic pigment concentrations measured by a HPLC (High-Performance Liquid Chromatography) technique. The CHEMTAX program determines the contribution of each phytoplankton class to total phytoplankton biomass (chlorophyll a) based on the ratios of marker pigment to chlorophyll a of phytoplankton group. In this study, the marker pigment/chlorophyll a ratios were investigated in phytoplankton species isolated from marine waters around the Korean peninsula. These results were used as the input pigment ratios of the CHEMTAX program to investigate phytoplankton community structure in Korean coastal waters (Yeoja and Gamak Bay). There were significant differences in the ratios of marker pigment to chlorophyll a among the different species within the same algal class. There was a significant difference between the values of our ratios and the previously used ratios in other regions of the world. When phytoplankton community composition was calculated using our initial ratios in Yeoja and Gamak Bay, our results were significantly different from the results calculated on the basis of initial ratios of marker pigment in phytoplankton suggested in other marine waters. The estimates of the contributions of the major algal groups (bacillariophyceae and dinophytes) to total chlorophyll a varied within 5% depending on the initial ratios chosen. The variations of estimates for the pico- and nanoplankton (cyanophytes and prasinophytes), which have relatively low contributions to total chlorophyll a, were higher than those for major algal group. Although the HPLC-pigment measurements combined with CHEMTAX analysis are useful for identifying and qualifying phytoplankton community structure, further researches for the pigment ratios of the dominant phytoplankton species presenting in a given area are also needed.

Occupational Stress of Hospital Workers (병원종사자의 직업성 스트레스에 관한 연구 - 서울시내 500병상 이상 병원종사자를 중심으로 -)

  • Lee, Woo-Cheon
    • Korea Journal of Hospital Management
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    • v.3 no.1
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    • pp.1-33
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    • 1998
  • The purpose of this thesis is to study theoretical access to the methods that have been used for the research of occupational stress, thereby providing management methods of occupational stress of hospital workers. With a stress model of hospital workers set up from the viewpoint of organization management, 929 sets of questionnaires were collected from intern doctors, resident doctors, nurses, nursing aides, pharmacists, medical technicians, workers in patient affairs(reception and medical insurance workers), administrators and clerks from the 8 hospitals in Seoul with more than 500 beds. Upon variance analysis, correlation analysis and regression analysis of the collected questionnaires, this work examined how differences in stress caused by specific occupations and formulated a method of stress management for the hospital workers. The results are as follows. 1) If some duties of the nurses suffering from role-overloaded stress are transferred to the nursing aides dissatisfied with insufficient role, the two grunting groups can be satisfied at the same time. It is also necessary to transfer some jobs of the overloaded workers in patient affairs to the administrators, or the other way around. To reduce stress of conflict and ambiguity of role caused by the obscure division of roles between the workers, the role of each occupation should be delineated and the clear division of roles should be translated into action strictly according to that delineated. 2) Stress of inefficiency of organization from which the student doctors suffer can be relieved by management of participation. If they have access to the process of decision-making in general hospital affairs and consequently their understanding and the autonomy of job performance are promoted, such stress will be reduced. 3) To cope with stress of career development from which nurses, medical technicians, administrators, workers in patient affairs suffer, it is necessary to establish whether they have a chance to revive their careers, whether there are any ways of remotivation for less contributive workers, and whether they encourage each other to develope their careers. If they are given a chance to develope their careers, such stress will be relieved. 4) Pharmacists, suffering from stresses of living and personal relations, have strong cohesive power among themselves and organize a well-integrated team; thereby reducing the stress of personal relations and increasing productivity. 5) For administrators and student doctors confined to lesser social supports and for nurses and workers in patient affairs whose recognition of stress and job satisfaction are affected by social supports, emotional and informational supports for job performance help alleviate an individual's mental, and physical stress. 6) In addition to the above-mentioned stress-management methods, if an organizational coping strategy is provided according to the types of stress from the general viewpoint of the whole group of hospital workers, it would be of great help to managing stress. For example, the redesign of jobs, the management of objective, the improvement of working environment, the formation of an autonomous working group and various working plans can be set up for those who suffer from stress related to inappropriate role, while career counseling and development of career process can be provided for those dissatisfied with career development. Participation in the process of decision-making and the restructuring of the organization are needed for those who suffer from stress of malfunctioning organization, whereas creation of a supportive organizational atmosphere is desired for those who feel stressed due to personal relations. As well, such organizational coping strategies. as the increase of welfare facilities, seminars and educational programs and provision of health-promotion facilities can be provided.

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A study on names of weapons in martial arts book, Unhae in Joseon Dynasty (조선시대 무예서 언해에 나타난 무기명 고찰)

  • Kwak, Nak-hyun;Lee, Hyun-Ju
    • (The)Study of the Eastern Classic
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    • no.57
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    • pp.263-299
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    • 2014
  • This study aims to look into weapons names mentioned in "Unhae", a book of traditional martial arts annotated into Korean. Comprehensive conclusions drawn from this are as follow. First, the annotated martial arts book is compiled to the order of Muyejaebo of year 1598, Muyejaebobunyuksokjib(A annotated attachment to Mooyejebo) of year 1610, Moojesinbo of year 1759, and Muyedobotongji of year 1790. Second, in the martial arts book are a total of 24 weapons with 4 types of spears, swords, bare hands & poles, and horseback weapons. Weapon names of ?Unhae? taken into detailed analysis, spears are 5 types of Jangchang (long spears), Jukjangchang (long spears made of bamboo), Keechang (flagged spears), Dgangpa (skewered spears), and Nangseon (forked spears). Swords are 10 types of Ssangsoodo (two-handed swords), Yedo (pointed swords), Waegum (Japanese swords), Waegumkyojun (Japanese battle swords), Jedokgum (Admiral's swords), Bongukgum (native swords), Ssanggum (coupled swords), Woldo (moon swords), Hyupdo (narrow swords), Deungpae (swords made of rattan). Bare hands & poles are 3 types of Gwonbeop (fists), 7070 Gonbang (clubs), and Pyeon-gon (flailed clubs). Horseback weapons are 6 types of flagged spears, MasangSsanggum (coupled horseback spears), MasangWoldo (horseback moon swords), MasangPyeon-gon (horseback flailed clubs), Kyukgoo (striking poles), and Masangjae (horse postures). Third, spears of the martial arts book, "Unhae" had the function as long weapons and were used for military drills of the infantry. Swords had the function as short weapons, and were used for military drills of the infantry. Bare hands & poles had the function as short weapons and were used for military drills of the infantry. Horseback weapons composed of short and long weapons were used for military drills of the cavalry. In addition to these, Kyukgoo (striking poles), and Masangjae (horse postures) were martial arts to which entertaining elements were added. Fourth, the difference in its compiling is that Mooyejebo and A annotated attachment to Mooyejebo place both Chinese characters and Korean annotation in the context together with introduction of weapons while Moojedobo Tongji explains weapons in Chinese and compiles a separate copy of Korean annotation that explains mainly postures in each lineage of martial arts for soldiers to acquire practical skills.

Study on the Effect of Self-Disclosure Factor on Exposure Behavior of Social Network Service (자기노출 요인이 소셜 네트워크 서비스의 노출행동에 미치는 영향에 관한 연구)

  • Do Soon Kwon;Seong Jun Kim;Jung Eun Kim;Hye In Jeong;Ki Seok Lee
    • Information Systems Review
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    • v.18 no.3
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    • pp.209-233
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    • 2016
  • Internet companies that utilize social network have increased in number. The introduction of diverse social media services facilitated innovative changes in e-business. Social network service (SNS), which is a domain of social media, is a web-based service designed to strengthen human relations in the Internet and build new social relations. The remarkable growth of social network services and the profit generation and perception of this service are the new growth engines of this digital age. Given this development, many global IT companies views SNS as the most powerful form of social media. Thus, they invest efforts to develop business models using SNS.2) This study verifies the impact of privacy exposure in SNS as a result of privacy invasion. This study examines the purpose of using the SNS and user's awareness of the significance of personal information, which are key factors that affect self-disclosure of personal information. This study utilizes theory of reasoned action (TRA) to provide a theoretical platform that describes the specific behavior and emotional response of individuals. This study presents a research model that considers negative attitude (negatude). In this model, self-disclosure in SNS is considered a TRA. TRA is a subjective norm, a behavioral intention, and a key variable of exposure behavior. A survey was conducted on college students at Y university in Seoul to empirically verify the research model. The students have experiences in using SNS. A total of 198 samples were collected. Path analysis was applied to analyze the relations of factors. The results of path analysis show the statistically insignificant impact of privacy invasion on negatude, subjective norm, behavioral intention, and exposure behavior. The impact of unrecognized privacy invasion was also considered insignificant. The impacts of intention to use SNS on negatude, subjective norm, behavioral intention, and exposure behavior was significant. A significant impact was also found for the significance of personal information on subjective norm, behavioral intention, and exposure behavior, whereas the impact on negatude was insignificant. The impact of subjective norm on behavioral intention was significant. Lastly, the impact of behavioral intention on exposure behavior was insignificant. These findings are significant because the study examined the process of self-disclosure by integrating psychological and social factors based on theoretical discussion.

Betweenness Centrality-based Evacuation Vulnerability Analysis for Subway Stations: Case Study on Gwanggyo Central Station (매개 중심성 기반 지하철 역사 재난 대피 취약성 분석: 광교중앙역 사례연구)

  • Jeong, Ji Won;Ahn, Seungjun;Yoo, Min-Taek
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.3
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    • pp.407-416
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    • 2024
  • Over the past 20 years, there has been a rapid increase in the number and size of subway stations and underground structures worldwide, and the importance of safety for subway users has also continuously grown. Subway stations, due to their structural characteristics, have limited visibility and escape routes in disaster situations, posing a high risk of human casualties and economic losses. Therefore, an analysis of disaster vulnerabilities is essential not only for existing subway systems but also for deep underground facilities like GTX. This paper presents a case study applying a betweenness centrality-based disaster vulnerability analysis framework to the case of Gwanggyo Central Station. The analysis of Gwanggyo Central Station's base model and various disaster scenarios revealed that the betweenness centrality distribution is symmetrical, following the symmetrical spatial structure of the station, with high centrality concentrated in the central areas of basement levels one and two. These areas exhibited values more than 220% above the average, indicating a high likelihood of bottleneck phenomena during evacuation in disaster situations. To mitigate this vulnerability, scenarios were proposed to distribute evacuation flows concentrated in the central areas, enhancing the usability of peripheral areas as evacuation routes by connecting staircases continuously. This modification, when considered, showed a decrease in centrality concentration, confirming that the proposed addition of evacuation paths could effectively contribute to dispersing the flow of evacuation in Gwanggyo Central Station. This case study demonstrates the effectiveness of the proposed framework for assessing evacuation vulnerability in enhancing subway station user safety and can be effectively applied in disaster response and management plans for major underground facilities.