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Development and Evaluation of Silicon Passive Layer Dosimeter Based Lead-Monoxide for Measuring Skin Dose (피부선량 측정을 위한 Lead-Monoxide 기반의 Silicon Passive layer PbO 선량계 개발 및 평가)

  • Yang, Seung-Woo;Han, Moo-Jae;Jung, Jae-Hoon;Bae, Sang-Il;Moon, Young-Min;Park, Sung-Kwang;Kim, Jin-Young
    • Journal of the Korean Society of Radiology
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    • v.15 no.6
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    • pp.781-788
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    • 2021
  • Due to the high sensitivity to radiation, excessive exposure needs to be prevented by accurately measuring the dose irradiated to the skin during radiation therapy. Although clinical trials use dosimeters such as film, OSLD, TLD, glass dosimeter, etc. to measure skin dose, these dosimeters have difficulty in accurate dosimetry on skin curves. In this study, to solve these problems, we developed a skin dosimeter that can be attached according to human flexion and evaluated its response characteristics. For the manufacture of the dosimeter, lead oxide (PbO) with high atomic number (ZPb: 82, ZO: 8) and density (9.53 g/cm3) and silicon binders that can bend according to human flexion were used. In the case of a dosimeter made of PbO material, the performance degradation has been prevented by using parylene and others due to the presence of degradation due to oxidation, but the previously used parylene is affected by bending, so a new form of passive layer was produced and applied to the skin dosimeter. The characteristic evaluation of the skin dosimeter was evaluated by analyzing SEM, reproducibility, and linearity. Through SEM analysis, bending was evaluated, reproducibility and linearity at 6 MeV energy were evaluated, and applicability was assessed with a skin dosimeter. As a result of observing the dosimeter surface through SEM analysis, the parylene passive layer PbO dosimeter with the positive layer raised to the parylene produced cracks on the surface when bent. On the other hand, no crack was observed in the silicon passive layer PbO dosimeter, which was raised to silicon passive layer. In the reproducibility measurement results, the RSD of the silicon passive layer PbO dosimeter was 1.47% which satisfied the evaluation criteria RSD 1.5% and the linearity evaluation results showed the R2 value of 0.9990, which satisfied the evaluation criteria R2 9990. The silicon passive layer PbO dosimeter was evaluated to be applicable to skin dosimeters by demonstrating high signal stability, precision, and accuracy in reproducibility and linearity, without cracking due to bending.

Changes in prevalence of obesity according to gender in Korea adults: Using a population-based Korea National Health Check-up Database, 2011-2013 (우리나라 성인의 성별에 따른 비만유병률의 변화 : 국민건강보험 건강검진(2011-2013) 자료 이용)

  • Choi, Oh-Jong;Cho, Sung-Il
    • Korean Public Health Research
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    • v.44 no.4
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    • pp.87-97
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    • 2018
  • Background: Recently, the prevalence of obesity (body mass index [BMI] ${\geq}25kg/m^2$) has been increasing rapidly worldwide over a short period. In Korea, the prevalence of obesity has also increased rapidly due to the rapid socio-economic development and lifestyle changes, with differing patterns according to gender. This study aimed to compare the change in obesity prevalence according to gender among the adult population in Korea using representative data, the National Health Check-up Database (NHCD), to follow-up individuals who had undergone checkups during both years in Korea (2011~2013). Methods: To analyze the changes in obesity prevalence in the recent two years, data regarding men and women who had undergone health check-ups in both two years (2011, 2013) were extracted. The final study population comprised 144,934 persons: 83,604 (58%) males and 61,330 (42%) females. Chi-square test within a univariate analysis, and the level of factor difference was verified with t-test, one-way ANOVA and multiple comparison. Results: In 2011, one out of three participants was obese (BMI ${\geq}25kg/m^2$; male, 37.7%; female, 27.3%) and more than half of the subjects were overweight (BMI ${\geq}23kg/m^2$; male, 65.6%; female, 50.4%) requiring obesity management. For the two years, the BMI of the participants significantly increased (p < .0001) and the prevalence of obesity increased among both males and females. The prevalence of obesity was higher among both genders with a longer duration of smoking, more smoking, family history of hypertension, and family history of diabetes. However, residence, income level, drinking status, psychiatric disorder, disability status and severity of disability were the opposite gender. Conclusion: In the analysis of data, the prevalence of obesity among both men and women was increasing. The degree of change in the prevalence of obesity among men and women was different in each variable. Thus, it will need to consider gender in developing health policies for obesity mediation and to provide integrated healthcare and management for those people.

A Study on Classification System for Gong-Po-Do Style in Tomb Wall Paintings of Koguryo (고구려 고분벽화 공포도 형식의 분류체계에 관한 연구)

  • Hwang, Se-Ok
    • Korean Journal of Heritage: History & Science
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    • v.49 no.2
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    • pp.20-55
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    • 2016
  • Koguryo's tomb mural paintings in North Korea are our precious cultural heritage which have been designated as UNESCO World Heritage property receiving high praise in the following criterion, i) exceptional creativeness of human being, ii) representative value showing the stage of development in construction history of East-Asia, iii) aesthetic superiority iv) uniqueness of building construction including tombs' ceiling. Mural paintings have been found from almost 100 tombs of the Koguryo dynasty out of 130 which are scattered across Huanren County, Lianoning Province, Ji'an, Jilin Province in China and Pyongyang in North Korea. Especially, most of them are gathered in Pyongyang from 4th and 5th century. Peculiarly, some of them have been constructed before King Jangsu's transfer of the capital to Pyongyang(AD 427). It can be regarded that Pyongyang territory had been under control of Koguryo and to become a new capital in the near future. And dense emergence of such tombs since the capital transfer from Gungnae City to Pyongyang during the reign of Jangsu is linked closely to the construction of tombs for rulers under strengthen royal authority of Jangsu and centralized system of authoritarian rule. Tomb mural paintings describe the owner's figure pictorially based on the truth just as in his living years. General lifestyles of ruling powers and sovereigns can be seen from the wall paintings portraying several buildings with various styles, figures, manners of living, which are considered that the tomb owner had led politically and sociologically in his life. In spite of not enough proofs to approve figure of architectures or "Gong-Po" in wall paintings on the tombs as those of Koguryo, it is persuasive with consideration for painting and decoration inside the tomb like wooden building in real life for the purpose of reenacting and continuing the tomb owner's luxurious life after death. "Du-Gong-Po-Zak" had appeared in company with Koguryo tomb murals and it can be found in most of the murals. And the emergence of substantial "Gong-Po-Do" can be counted more than a century ahead of the figure in murals. It could be a reasonable assumption as regards Koguryo tomb murals time of appearance match up with production period of Gahyungmyunggi(家形明器) and Hwasangseok(畵像石) Hwasangjeon(畵像塼) Design in the Mural Painting of the East-Han(東漢) Ancient Tombs in China. On this study, architectural "Gong-Po"s described in Koguryo tomb murals are categorized largely in "Bi(non)-Po-Zak-kye", "Jun(semi)-Po-Zak-kye", and "Po-Zak-kye" based on presence of "Ju-Du", "Cheom-Cha", and "Cheom-Cha-Sal-Mi" with developmental aspect, and, "Po-zak" is subdivided as "Bi(non)-Cheul-Mok" and "Cheul-Mok" types.

A Study on the Verification of an Indoor Test of a Portable Penetration Meter Using the Cone Penetration Test Method (자유낙하 콘관입시험법을 활용한 휴대용 다짐도 측정기의 실내시험을 통한 검증 연구)

  • Park, Geoun Hyun;Yang, An Seung
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.2
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    • pp.41-48
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    • 2019
  • Soil compaction is one of the most important activities in the area of civil works, including road construction, airport construction, port construction and backfilling construction of structures. Soil compaction, particularly in road construction, can be categorized into subgrade compaction and roadbed compaction, and is significant work that when done poorly can serve as a factor causing poor construction due to a lack of compaction. Currently, there are many different types of compaction tests, and the plate bearing test and the unit weight of soil test based on the sand cone method are commonly used to measure the degree of compaction, but many other methods are under development as it is difficult to secure economic efficiency. For the purpose of this research, a portable penetration meter called the Free-Fall Penetration Test (FFPT) was developed and manufactured. In this study, a homogeneous sample was obtained from the construction site and soil was classified through a sieve analysis test in order to perform grain size analysis and a specific gravity test for an indoor test. The principle of FFPT is that the penetration needle installed at the tip of an object put into free fall using gravity is used to measure the depth of penetration into the road surface after subgrade or roadbed compaction has been completed; the degree of compaction is obtained through the unit weight of soil test according to the sand cone method and the relationship between the degree of compaction and the depth of the penetration needle is verified. The maximum allowable grain size of soil is 2.36 mm. For $A_1$ compaction, a trend line was developed using the result of the test performed from a drop height of 10 cm, and coefficient of determination of the trend line was $R^2=0.8677$, while for $D_2$ compaction, coefficient of determination of the trend line was $R^2=0.9815$ when testing at a drop height of 20 cm. Free fall test was carried out with the drop height adjusted from 10 cm to 50 cm at increments of 10 cm. This study intends to compare and analyze the correlation between the degree of compaction obtained from the unit weight of soil test based on the sand cone method and the depth of penetration of the penetration needle obtained from the FFPT meter. As such, it is expected that a portable penetration tester will make it easy to test the degree of compaction at many construction sites, and will lead to a reduction in time, equipment, and manpower which are the disadvantages of the current degree of compaction test, ultimately contributing to accurate and simple measurements of the degree of compaction as well as greater economic feasibility.

Anti-inflammatory Effect of Heat-Killed Enterococcus faecalis, EF-2001 (열처리 사균체 엔테로코커스 패칼리스 EF-2001의 항염증 효과)

  • Choi, Moon-Suk;Chang, Sang-Jin;Chae, Yuri;Lee, Myung-Hun;Kim, Wan-Joong;Iwasa, Masahiro;Han, Kwon-Il;Kim, Wan-Jae;Kim, Tack-Joong
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1361-1368
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    • 2018
  • Inflammation is the most common condition in the human body. Tissue damage triggers inflammation, together with vasodilation and increased blood flow at the inflamed site, resulting in edema. Inflammatory responses are also triggered by lipopolysaccharide (LPS), a Toll-like receptor Enterococcus faecalis, a gram-positive organism, has been reported to possess immunomodulatory and preventive activities; however, its use may present risks of sepsis and other systemic infections. Heat-killed Enterococcus faecalis (EF-2001) has been reported to induce antitumor activity, but its effects on inflammation are not known. In the present study, we investigated the effect of EF-2001 on LPS-induced macrophage inflammatory responses. EF-2001 treatment reduced nitric oxide (NO) production, indicating suppression of inflammatory reactions. EF-2001 showed no cytotoxicity in macrophages. Further investigation of the anti-inflammatory mechanism of EF-2001 indicated that EF-2001 reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2. EF-2001 also reduced f the LPS induction of several inflammatory molecules involved in the nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) and mitogen-activated protein kinase pathways, including ERK, JNK, and p38 phosphorylation, in a concentration-dependent manner. Additionally, EF-2001 inhibited Akt phosphorylation and increased the expression of the inhibitory ${\kappa}B$ ($I{\kappa}B$) protein, an inhibitor of $NF-{\kappa}B$. EF-2001 also inhibited the nuclear translocation of p65. These results suggest that EF-2001 has anti-inflammatory properties and may be useful for treating inflammatory diseases.

'Dual Transformation' of Freedom of Information Movements and Civic Participation (정보공개운동의 '이중적 전환'과 시민참여 : <참여연대 정보공개사업단>과 <투명사회를 위한 정보공개센터> 비교를 중심으로)

  • Hong, Il-Pyo
    • The Korean Journal of Archival Studies
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    • no.22
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    • pp.37-76
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    • 2009
  • This paper aims-through comparative research on two organizations and use of political process theory-to analyze the historical development of, current issues related to and the characteristics of the new transformation of the Freedom of Information Movements (FOIMs) in South Korea. In the ten years since the Freedom of Information Act (FOIA) took effect in 1998, Korean FOIMs have developed along the following course: 'emergence' (1998), 'expansion and extension' (1999-2004), 'institutionalization and retro-institutionalization-' (2005-2008). Specifically, in the early stage of FOIMs, the Freedom of Information (FOI) department of the People's Solidarity for Participatory Democracy, established in 1998, had led the FOI movement by initiating reform of the FOI institution and advocating an end to old practices. Paradoxically, however, following the institutional progress of FOI under the Roh Moo Hyun government, the vitality of FOIMs seemed to be weakening. And under the Lee Myung Bak government, which is showing regression in both the FOI institution and practices, the 'dual transformation' of the FOIMs is being led not by old groups but by new ones. The Center for Freedom of Information and Transparent Society(CFOI), which was founded in 2008, has journalists, researchers of archival studies, citizens, lawyers and nongovernmental activists as members. Through its blog style Homepage, countless reports are becoming "open to the public" and "share with the public." And its various civic education programs are interactive bridges which enable mutual communication between the Center and citizens. CFOI is expanding the FOI movement in different ways than the traditional activists such as the FOI department of the PSPD department, which worked through methods such as policy proposals, disclosing information litigation, comments and public statements, and hosting forums. CFOI is leading the 'dual process of transformation' of FOIMs, namely the transformation from an 'advocacy' movement to an 'empowerment' movement and transformation of the FOI movement's framework from "open to the public" to "share with the public."

Seedling Quality, and Early Growth and Fruit Productivity after Transplanting of Squash as Affected by Plug Cell Size and Seedling Raising Period (플러그 셀 크기와 육묘일수에 따른 애호박의 묘 소질, 정식 후 초기 생육 및 과실 생산성)

  • Kim, Yeong Sook;Park, Yoo Gyeong;Jeong, Byoung Ryong
    • Journal of Bio-Environment Control
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    • v.28 no.3
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    • pp.185-196
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    • 2019
  • Abstract. This research was conducted to figure out the optimal size of the plug cell and seedling raising period in 'Nongwoo' and 'Nonghyeop' cultivars. In the first experiment on effect of plug cell size on growth of squash, seedlings were transplanted into hydroponic cultivation beds at different growing stages: Those in 32-cell trays with 3-4 true leaves at 25 days after sowing, those in 50-cell trays with 2 true leaves at 15 days after sowing, those in 105-cell trays just before a true leaf development, and those in 162-cell trays with only cotyledons at 8 days after sowing. In the second experiment on effect of seedling raising period on growth of squash, it was conducted to have different sowing dates. But the same transplanting date, based on the results of Experiment 1, and compared the differences in growth and fruit productivity as affected by plug cell size in the same way with experiment 1 including the cultivars and environmental conditions. After setting the transplanting date in advance, the number of days for sowing were calculated back for each treatment. In the first experiment, plant height was the greatest in 105-cell trays followed by 162, 50 and 32-cell trays in both cultivars. The best fruit quality was found in different treatments depending on the cultivars, although it was the lowest in 32-cell trays in both cultivars. The fruit quality was not significantly different among those from cell sizes. Therefore, when raising seedlings in 105-cell trays, the period of raising seedlings can be shortened as compared with the conventional 32-cell trays, and this change could reduce the workforce required for growing and transplanting seedlings. In the second experiment, after transplanting, shoot height and leaf width in the first measurement in both cultivars were greater in the 32-cell treatment. However, the last measurement after four weeks showed no significant difference in plant height, but significantly greatest leaf width in the smallest cell treatment, even as compared with that in 32-cell treatment. In case of 'Nongwoo', length and weight of the first harvested fruit showed the highest values in the treatment of 105-cell trays. In case of 'Nonghyeop' the 162-cell treatment along with the 105-cell treatment showed greatest length and weight of the first fruits. From these results, zucchini plug seedlings can be raised in plug trays with reduced cell sizes than the conventional 32-cell trays with improved fruit productivity.

Status of Exotic Plant Species with in the Cultural Properties in Seongju-gun, Gyeongsangbuk-do (성주지역 문화재 지정(보호)구역 내 외래식물의 현황)

  • Shin, Hyun Tak;Kim, Yong Shik;Yi, Myung Hoon;Yoon, Jung Won
    • Korean Journal of Heritage: History & Science
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    • v.44 no.1
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    • pp.162-181
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    • 2011
  • The purpose of this study was to analyze the current status of both exotic and naturalized plants in the designated Cultural Preservation Area located in Seongju-gun, Gyeongsangbuk-do in order to identify traditional cultural places and to provide basic information to prepare a conservation strategy. The vascular plant species was identified as having 114 taxa: 50 families, 93 genera, 94 species, 16 varieties and 4 forms in King Sejong's Prince Taesil. Among them are 15 taxa of the exotic plant species and 16 taxa of naturalized plant species, which resulted in 14.04% of the Naturalization Rate and 5.90% of the Urbanization Index. The vascular plant species was identified as 68 taxa: 40 families, 64 genus, 57 species, 8 varieties and 4 forms in the Seongju Hyanggyo. Among them, the exotic plants recorded 17 taxa with 30 taxa of naturalized plants. The Naturalization Rate was 44.12% and Urbanization Index was 11.07%. The Seongbaksup, which was a grove outside of the Seongju Fortress recorded 61 taxa: 34 families, 58 genera, 55 species, 5 varieties and 1 form. Among them, the exotic plant species consisted of 10 taxa with 17 taxa of naturalized plants, with a 27.87% Naturalization Rate and a 6.27% Urbanization Index. The vascular plant species was recorded as 230 taxa: 92 families, 183 genus, 182 species, 1 subspecies, 32 varieties and 14 forms in Hangae Village. Among them, exotic plants consist of 28 taxa with 85 naturalized plant species, with a Naturalization Rate of 37.12% and Urbanization Index of 31.37%. The vascular plant species in the Seongsan Ancient Tomb is recorded as having 131 taxa: 55 families, 107 genus, 106 species 19 varieties and 6 forms. Among them, exotic plants consist of 18 classifications, and naturalized plants consist of 22 classifications with a Naturalization Rate of 16.79% and an Urbanization Index of 8.12%. The Seongju Hangyo recorded the highest Naturalization Rate among all surveyed sites in Hangae Village. All five of these surveyed sites will require a management plan to eradicate both exotic and naturalized plant species. Hangae Village especially needs to prepare a management plan. The invasion of ragweed in Seongju Hanggyo and Hangae Village, which is one of the most invasive plant species to disturb the ecosystem, is in need of management to eradicate it.

A Study on Setup for Preliminary Decision Criterion of Continuum Rock Mass Slope with Fair to Good Rating (양호한 연속체 암반사면의 예비 판정기준 설정 연구)

  • Kim, Hyung-Min;Lee, Su-gon;Lee, Byok-Kyu;Woo, Jae-Gyung
    • The Journal of Engineering Geology
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    • v.29 no.2
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    • pp.85-97
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    • 2019
  • It can be observed that steep slopes ($65^{\circ}$ to $80^{\circ}$) consist of rock masses were kept stable for a long time. In rock-mass slopes with similar ground condition, steeper slopes than 1 : 0.5 ($63^{\circ}$) may be applied if the discontinuities of rock-mass slope are distributed in a direction favorable to the stability of the slope. In making a decision the angle of the slope, if the preliminary rock mass conditions applicable to steep slope are quantitatively setup, they may be used as guidance in design practice. In this study, the above rock mass was defined as a good continuum rock mass and the quantitative setup criterion range was proposed using RMR, SMR and GSI classifications for the purpose of providing engineering standard for good continuum rock mass conditions. The methods of study are as follows. The stable slope at steep slopes ($65^{\circ}$ to $80^{\circ}$) for each rock type was selected as the study area, and RMR, SMR and GSI were classified to reflect the face mapping results. The results were reviewed by applying the calculated shear strength to the stable analysis of the current state of rock mass slope using the Hoek-Brown failure criterion. It is intended to verify the validity of the preliminary criterion as a rock mass condition that remains stable on a steep slope. Based on the analysis and review by the above research method, it was analyzed that a good continuum rock mass slope can be set to Basic RMR ${\geq}50$ (45 in sedimentary rock), GSI and SMR ${\geq}45$. The safety factor of the LEM is between Fs = 14.08 and 67.50 (average 32.9), and the displacement of the FEM is 0.13 to 0.64 mm (average 0.27 mm). This can be seen as a result of quantitative representation and verification of the stability of a good continuum rock mass slope that has been maintained stable for a long period of time with steep slopes ($65^{\circ}$ to $80^{\circ}$). The setup guideline for a good continuum rock mass slope will be able to establish a more detailed setup standard when the data are accumulated, and it is also a further study project. If stable even on steep slopes of 1 : 0.1 to 0.3, the upper limit of steep slopes is 1 : 0.3 with reference to the overseas design standards and report, thus giving the benefit of ensuring economic and eco-friendlyness. Also, the development of excavation technology and plantation technology and various eco-friendly slope design techniques will help overcome psychological anxiety and rapid weathering and relaxation due to steep slope construction.

A Study on the Development of Assessment Index for Catastrophic Incident Warning Sign at Refinery and Pertrochemical Plants (정유 및 석유화학플랜트 중대사고 전조신호 평가지표 개발에 관한 연구)

  • Yun, Yong Jin;Park, Dal Jae
    • Korean Chemical Engineering Research
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    • v.57 no.5
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    • pp.637-651
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    • 2019
  • In the event of a major accident such as an explosion in a refinery or a petrochemical plant, it has caused a serious loss of life and property and has had a great impact on the insurance market. In the case of catastrophic incidents occurring in process industries such as refinery and petrochemical plants, only the proximate causes of loss have been drawn and studied from inspectors or claims adjustors responsible for claims of property insurers, incident cause investigators, and national forensic service workers. However, it has not been done well for conducting root cause analysis (RCA) and identifying the factors that contributed to the failure and establishing preventive measures before leading to chemical plant's catastrophic incidents. In this study, the criteria of warning signs on CCPS catastrophic incident waning sign self-assessment tool which was derived through the RCA method and the contribution factor analysis method using the swiss cheese model principle has been reviewed first. Secondly, in order to determine the major incident warning signs in an actual chemical plant, 614 recommendations which have been issued during last the 17 years by loss control engineers of global reinsurers were analyzed. Finally, in order to facilitate the assessment index for catastrophic incident warning signs, the criteria for the catastrophic incident warning sign index at chemical plants were grouped by type and classified into upper category and lower category. Then, a catastrophic incident warning sign index for a chemical plant was developed using the weighted values of each category derived by applying the analytic hierarchy process (pairwise comparison method) through a questionnaire answered by relevant experts of the chemical plant. It is expected that the final 'assessment index for catastrophic incident warning signs' can be utilized by the refinery and petrochemical plant's internal as well as external auditors to assess vulnerability levels related to incident warning signs, and identify the elements of incident warning signs that need to be tracked and managed to prevent the occurrence of serious incidents in the future.