• Title/Summary/Keyword: 최소단위

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Diatom Assemblages and its Paleoceanography of the Holocene Glaciomarine Sediments from the Western Antarctic Peninsula shelf, Antarctica (남극반도 서 대륙붕의 빙해양 퇴적물의 규조군집 특성과 고해양 변화)

  • Shin, Yu-Na;Kim, Yea-Dong;Kang, Cheon-Yoon;Yoon, Ho-Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.3
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    • pp.152-163
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    • 2001
  • Based upon the sedimentological, geochemical and micropaleontological analyses of two sediment cores from the Antarctic Peninsula (AP), three distinct lithological units can be recognized: (1) ice-proximal an/or ice-distal diamictons in the lower part of the cores, accumulated just seaward of the grounding line of the ice shlef until 11,000 yrs BP; (2) diatomaceous mud between 6,000 and 2,500 yrs BP in the middle part, resulted from a large influx of organic materials by enhanced production of open marine condition; (3) diatomaceous sandy mud since 2,500 yrs BP, characterized by an increase in sand content and decrease in TOC and diatom abundance in the lower layers, which reflects the formation of more extensive and seasonally persistent sea ice. Based on the C-14 radiocarbon dating, the sub-ice shlef deposition of the diamicton on the AP western shelf completed around 11,000 yrs BP. Colder condition was reinstated between 12,800 and 11,600 BP with a dropin TOC content and diatom abundance, which is coincident with the Younger Dryas event in the North Atlanticregion. At this time, the ice shelf, that is now absent in the study area, appears to advance as evidenced by an abrupt increase in sea-ice taxa. A climatic optimum is recognized between 9,000 and 2,500 BP, coincide witha mid-Holocene climatic optimum 'Hypsithermal Warm Period' from the other Antarctic sites. During this time, diatomaceous mud accumulated by a large influx of organic materials by enhanced production occurred in openmarine condition. Around 2,500 BP, diatomaceous sandy mud reflects the formation of more extensive and seasonally persistent sea ice, coincident with the onset of the Neoglacial in the Antarctic. Our results provide evidence of climatic change from the Antarctic Peninsula`s western shelf that helps in determining the existence and timing of Holocene milennial-scale climatic events in the Southern Hemisphere.

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SEDATION EVALUATION USING BIS INDEX ASSESSMENT WITH AND WITHOUT THE ADDED SUBMUCOSAL MIDAZOLAM (점막하 Midazolam의 병용투여 시 BIS 분석을 이용한 진정 평가)

  • Lee, Young-Eun;Park, Mi-Kyung;Kim, So-Young;Kim, Yun-Hee;Jung, Sang-Hyuk;Baek, Kwang-Woo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.1
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    • pp.91-98
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    • 2007
  • The aim of this study was to examine the difference of the depth of sedation using the Bispectral index assessment with and without the added submucosal Midazolam to oral Chloral hydrate and Hydroxyzine for pediatric patients. Twenty seven sedation cases were performed in this study Selection criteria included good health(ASA I), 2 to 6 years of age, the need for sedation to receive dental treatment including anesthesia, and restorative procedure over at least two teeth. Patients were randomly classified into one group taking oral Chloral hydrate(60 mg/kg) and Hydroxyzine(1 mg/kg) and the other group recieving Chloral hydrate(60 mg/kg), Hydroxyzine(1 mg/kg) and submucosal Midazolam(0.1 mg/kg). Nitrous Oxide(50%) was used for both group during sedation. Patients were monitored using a pulse oximeter and a Bispectral monitor. A behavior scale was rated as quiet(Q), crying(C), movement(M), or struggling(S) every 2 minutes watching a recorded videotape. Analysis showed a significant difference in mean Bispectral index and SD during sedation across two groups(P<0.001). The group of patients injected with submucosal Midazolam in addition to oral Chloral hydrate and Hydroxyzine showed a lower mean Bispectral index and a narrower SD. PR and SpO2 for both groups remained within the normal values. Submucosal Midazolam improved the sedation quality by deepening sedation depth without compromising safety and enabled the sedation pattern to be kept more stable.

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Three Crystal Structures of Dehydrated $Ag_{12-x}Na_x-A$ (x = 4, 6, and 8) Treated with Rubidium Vapor (탈수한 $Ag_{12-x}Na_x-A$ (x = 4, 6, 및 8)를 루비듐 증기로 처리한 세가지 결정구조)

  • Lee, Hyeon Do;Kim, Un Sik;Park, Jong Yeol;Kim, Yang
    • Journal of the Korean Chemical Society
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    • v.38 no.3
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    • pp.186-196
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    • 1994
  • Three fully dehydrated partially $Ag^+$-exchanged zeolite A(Ag_4Na_8-A, Ag_6Na_6-A, and Ag_8Na_4-A) were treated at $250^{\circ}C$ with 0.1 torr Rb vapor at 4 h. Their structures were determined by singlecrystal X-ray diffraction methods in the cubic space group $Pm{\bar3}m$ (a = 12.264(4) $\AA$, a = 12.269(1) $\AA$, and a= 12.332(3) $\AA$, respectively) at $22(1)^{\circ}C$, and were refined to the final error indices, R(weighed), of 0.056 with 131 reflections, 0.068 with 108 reflections, and 0.070 with 94 reflections, respectively, for which I > $3\sigma(I).$ In these structures, Rb species are found at three different crystallographic sites; three $Rb^+$ ions per unit cell are located at 8-ring centers, ca. 6.0∼6.8 $Rb^+$ ions are found opposite 6-rings on threefold axes in the large cavity, and ca. 2.5 $Rb^+$ ions are found on three fold axes in the sodalite unit. Also, Ag species are found at two different crystallographic sites; ca. 0.6∼1.0 $Ag^+$ ion lies opposite 4-rings and about 1.8∼4.2 Ag atoms are located near the center of the large cavity. In these structures, the numbers of Ag atoms per unit cell are 1.8, 3.0, and 4.2, respectively, and these are likely to form hexasilver clusters at the centers of the large cavities. The $Rb^+$ ions, by blocking 8-rings, may have prevented silver atoms from migrating out of the structure. Each hexasilver cluster is stabilized by coordination to 6-ring, 8-ring $Rb^+$ ions, and also by coordination to a 4-ring $Ag^+$ ion.

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Three Crystal Structures of Dehydrated Partially $Co^{2+}-Exchanged$ Zeolite A Treated with Potassium Vapor (부분적으로 코발트 이온으로 치환한 제올라이트 A를 진공 탈수한 후 칼륨 증기로 반응시킨 3개의 결정구조)

  • Jeong Mi Suk;Jang Se Bok
    • Korean Journal of Crystallography
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    • v.15 no.2
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    • pp.59-68
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    • 2004
  • Three crystal structures of dehydrated partially $Co^{2+}-exchanged$ zeolite A treated with 0.6 Torr of K at $300^{\circ}C$ (for 12 hrs, 6 hrs, and 2 hrs) vapor have been determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1)$^{\circ}C(a=12.181(1)\;{\AA},\;a=12.184(1)\;{\AA},\;and\;a=12.215(1)\;{\AA})\;respectively)$. Their structures were refined to the final error indices, R(weight) of 0.090 with 10 reflections, 0.091 with 82 reflections, and 0.090 with 80 reflections, respectively, for which $1>\sigma(I)$. In each structure, all four $Co^{2+}$ and four $Na^+$ ions to be reduced by K atoms. The cobalt and sodium atoms produced are no longer found in the zeolite. K species are found at five different crystallographic sites: three $K^+$ ions lie at the planes of 8-rings, filling that position, ca. 11.5 K^+$ ions lie on threefold axes, ca. 4.0 in the large cavity and ca. 4.0 in the sodalite cavity, and ca. 0.5 $K^+$ ion is found near a 4-ring. ca. three $K^0$ atoms are found deep into the large cavity on threefold axes. In these structures, crystallographic results show that cationic tetrahedral $K_4$ (and/or triangular $K_3$) clusters have formed in the sodalites of zeolite A. The $K_4$ and/or $K_3$ clusters coordinate trigonally to three oxygens of a six-oxygen ring. The partially reduced ions of these clusters interact primarily with oxygen atoms of the zeolite structure rather than with each other. ca. 14.5K species are found per unit cell, more than the twelve $K^+$ ions needed to balance the anionic charge of zeolite framework, indicating that sorption of $K^0$ has occurred. The three $K^0$ atoms in the large cavity are closely associated with three out of four $K^+$ ions in the large cavity to form $K_7^{4+}$ clusters. The $K_7^{4+}$ cluster not interacts primarily with framework oxygens.

GPU-based dynamic point light particles rendering using 3D textures for real-time rendering (실시간 렌더링 환경에서의 3D 텍스처를 활용한 GPU 기반 동적 포인트 라이트 파티클 구현)

  • Kim, Byeong Jin;Lee, Taek Hee
    • Journal of the Korea Computer Graphics Society
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    • v.26 no.3
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    • pp.123-131
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    • 2020
  • This study proposes a real-time rendering algorithm for lighting when each of more than 100,000 moving particles exists as a light source. Two 3D textures are used to dynamically determine the range of influence of each light, and the first 3D texture has light color and the second 3D texture has light direction information. Each frame goes through two steps. The first step is to update the particle information required for 3D texture initialization and rendering based on the Compute shader. Convert the particle position to the sampling coordinates of the 3D texture, and based on this coordinate, update the colour sum of the particle lights affecting the corresponding voxels for the first 3D texture and the sum of the directional vectors from the corresponding voxels to the particle lights for the second 3D texture. The second stage operates on a general rendering pipeline. Based on the polygon world position to be rendered first, the exact sampling coordinates of the 3D texture updated in the first step are calculated. Since the sample coordinates correspond 1:1 to the size of the 3D texture and the size of the game world, use the world coordinates of the pixel as the sampling coordinates. Lighting process is carried out based on the color of the sampled pixel and the direction vector of the light. The 3D texture corresponds 1:1 to the actual game world and assumes a minimum unit of 1m, but in areas smaller than 1m, problems such as stairs caused by resolution restrictions occur. Interpolation and super sampling are performed during texture sampling to improve these problems. Measurements of the time taken to render a frame showed that 146 ms was spent on the forward lighting pipeline, 46 ms on the defered lighting pipeline when the number of particles was 262144, and 214 ms on the forward lighting pipeline and 104 ms on the deferred lighting pipeline when the number of particle lights was 1,024766.

Profiles of Local Fibrinolytic Activity before and after Urokinase Injection Into the Human Empyema Cavity (농흉환자에서의 늑막강내 유로키나제주입 전후의 섬유소 용해에 관한 연구)

  • Kim, Yong-Hoon;Kim, Jong-Bong;Moon, Jong-Ho;Song, Dong-Wha;Kim, Hyeon-Tae;Yang, Dong-Ho;Lee, Sang-Moo;Uh, Soo-Taek;Park, Choon-Sik
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.4
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    • pp.378-383
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    • 1993
  • Background: In recent reports, it has been reported that increased coagulation and decreased fibrinolytic activity has been responsible for abnormal fibrin turnover in exudative pleural effusion. In the cases of empyema, the fibrinopurulent stage is characterized by the fibrin deposition resulting in formation of limiting membranes in the visceral and parietal pleura. Recently attention has been focused on intrapleural fibrinolytic therapy capable of removing intrapleural fibrin deposits by urokinase (UK) in the treatment of empyema. However, these clinical trials have provided the clinical evidences for resolution of pleural loculation after intrapleural urokinase injection (UK-injection), the profiles of fibrinolytic activity following the treatment were still not investigated. Therefore in order to demonstrate the fibrinolytic evidences behind the clinical efficacy of intracavitary UK-injection, we examined intrapleural plasminogen activator activity (PA-activity) and D-dimer (D-Di) concentrations before and after each repeated UK-injection into the pleura in subjects with loculated empyema cavity. Methods: In a group of 14 patients with multiple loculated empyema cavity, PA-activity and D-Di concentrations were measured before and after repeated UK-injection. One hundred thousand IU of UK was injected at each time and all sujects had at least two times of UK injection accoring to clinical decisions. Nine out of 14 sujects had three times of UK-injection. Results: The mean (${\pm}SE$) PA-activity prior to treatemnt was $10.5{\pm}7.0$ and it was increased to $91.9{\pm}27.0,\;432.3{\pm}177.1,\;170.0{\pm}85.3$ IU tPA/ml after first, second and third time of UK-injection respectively (p<0.01). D-Di concentrations were also increased from $4.16{\pm}1.06{\times}10^5$ to $9.62{\pm}1.54{\times}10^5,\;12.31{\pm}1.89{\times}10^5,\;8.54{\pm}1.56{\times}10^5$ ng/ml in the same order as above (p<0.05). Conclusion: The suppressed fibrinolytic activity in the empyema cavity get removed sinificantly after inrracavitary injection of urokinase by generation of additional intrapleural plasmin.

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Urban Building Change Detection Using nDSM and Road Extraction (nDSM 및 도로망 추출 기법을 적용한 도심지 건물 변화탐지)

  • Jang, Yeong Jae;Oh, Jae Hong;Lee, Chang No
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.38 no.3
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    • pp.237-246
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    • 2020
  • Recently, as high resolution satellites data have been serviced, frequent DSM (Digital Surface Model) generation over urban areas has been possible. In addition, it is possible to detect changes using a high-resolution DSM at building level such that various methods of building change detection using DSM have been studied. In order to detect building changes using DSM, we need to generate a DSM using a stereo satellite image. The change detection method using D-DSM (Differential DSM) uses the elevation difference between two DSMs of different dates. The D-DSM method has difficulty in applying a precise vertical threshold, because between the two DSMs may have elevation errors. In this study, we focus on the urban structure change detection using D-nDSM (Differential nDSM) based on nDSM (Normalized DSM) that expresses only the height of the structures or buildings without terrain elevation. In addition, we attempted to reduce noise using a morphological filtering. Also, in order to improve the roadside buildings extraction precision, we exploited the urban road network extraction from nDSM. Experiments were conducted for high-resolution stereo satellite images of two periods. The experimental results were compared for D-DSM, D-nDSM, and D-nDSM with road extraction methods. The D-DSM method showed the accuracy of about 30% to 55% depending on the vertical threshold and the D-nDSM approaches achieved 59% and 77.9% without and with the morphological filtering, respectively. Finally, the D-nDSM with the road extraction method showed 87.2% of change detection accuracy.

Chemical and Optical Absorption Spectroscopic Study of Colored Tourmalines (유색 전기석의 화학적 및 광학흡수 분광학적 연구)

  • Kim, Hee-Jong;Kim, Soo-Jin
    • Journal of the Mineralogical Society of Korea
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    • v.6 no.1
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    • pp.1-16
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    • 1993
  • The chemical and optical absorption spectroscopic characters of pink and colorless tourmalines from San Diego mine in California, U.S.A., blue/green tourmalines from anonymous mine, Brazil, and brownis black tourmalines from Uncheon and Haksan mines in Korea have been studied using X-ray diffractometer, electron microprobe, optical absorption spectroscopy, and heat treatment. Least-squares refinements give unit cell diminsions : a = 15.96-16.01 ${\AA}$, c = 7.15-7.16 ${\AA}$ for the brownish black tourmalines, a = 15.82 - 15.87 ${\AA}$, c = 7.09 - 7.10 ${\AA}$ for pink tourmalines, and a = 15.88 - 15.94 ${\AA}$, c = 7.12 - 7.15 ${\AA}$ for blue green tourmalines. The colors of tourmalines are responsible for the transition elements. The pink color is attributed to the $Mn^{3+}$ ions, the blue-green to $Fe^{2+}$ and $Mn^{2+}$, bluish green to $Cu^{2+}$, and the brownish black to $Fe^{2+}$, $Fe^{2+}$ - $Fe^{3+}$, and $Fe^{2+}$ - $Ti^{4+}$. The $Mn^{3+}$ ions of pink color tourmalines are stabilized in the Y sites compressed along the O(1)H-O(3)H axis by Jahn-Teller distortion. Heating removes the pink or red component from tourmalines, producing the colorless stones from the pink and red ones. The bluish green samples change into the greenish blue ones and a certain yellowish green samples change into the light green ones by heat treatment. In the elbaite-schorl series, the concentration of Fe and Mn are variable depending on the color zones. The green zone is characterrized by the high content of Fe and Mn are variable depending on the color zones. The green zone is characterized by the high content of Fe, whereas the pink zone by the high content of Mn. Mn increases in deep yellow zone compared with yellow or colorless zones.

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Teachers' Importance Perception of the Contents in Housing Unit of Middle School Technology and Home Economics Subject (중학교 기술 가정 교과의 주생활단원 내용에 대한 교사의 중요도 인식)

  • Jun, Kyung-Sook
    • Journal of Korean Home Economics Education Association
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    • v.20 no.4
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    • pp.223-237
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    • 2008
  • The purpose of this research was to provide the information needed for improving the contents in housing unit of middle school technology and home economic textbook. For this purpose, a survey questionnaire was developed to examine teachers' importance perception of 48 contents in housing unit. A direct survey and an e-mail survey were used to collect data from teachers, and a total number of 233 data were analyzed. Conclusions were summarized as following: 1. Among the 48 contents in housing unit, the average score of teachers' importance perception of the 18 contents on 'interior environment and equipments' was 3.94; the average score of teachers' importance perception of the 15 contents on 'living space plan and use' was 3.78; and the average score of teachers'importance perception of the 15 content on 'housing maintenance and repair' was 3.42. Therefore, the 15 contents on 'housing maintenance and repair' must be revised. 2. Teachers' importance perception of 25 contents, among the 48 contents in housing unit, were significantly differentiated by gender, age, teaching experience, scholastic attainment, subject in charge(technology, home economics, technology and home economics), school type(boys' middle school, girls' middle school, coeducation), and region(city, county). Therefore, the 25 contents, of which importance perception were influenced by teachers' characteristics, must be revised in order to maintain the consistent importance perception. Suggestions were that the team teaching of technology and home economic textbook was more recommendable; that the local situations must be considered in the contents of housing unit and; that the contents of housing unit must be segmented into a minimum unit for the accurate evaluation.

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Analysis on the Growth Environment of Chionanthus retusus Community at the Wansanchielbong in Jeonju (전주 완산칠봉 이팝나무 자생지의 생육환경으로 본 자연유산 가치 분석)

  • Kim, Yeon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.4
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    • pp.85-97
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    • 2010
  • This study analyzed the distribution, structure and environmental condition of the vegetation of the Chionanthus retusus Lindly et Paxton community at the Wansanchielbong in the Jeonju city to offer basic data for sustainable conservation and ecological management system. And the results are as follows; 1. The average pH of soil at the community was pH 5.69 and it was slightly higher than the average of forest soil pH of Korea. But if the degree of pH will be down, it will be needed some more fertilization of Calcium. 2. The total average for contents of organism was 4.98%. And the nitrate - nitrogen content(mg/kg) of A, B, C, D quadrat was 20.29%, 28.87%, 7.65%, and 23.3% respectively. And there were good condition except quadrat C which was contaminated by amount of earth and sand. 3. The flora of the Chionanthus retusus Lindly et Paxton community was listed as 60 taxa; 37 families, 50 genera, 47 species, 10 varieties and 3 forms. The average appearance species of each Quadrat were A sector 30, B sector 26, C sector 19 and D 19 taxa respectively. 4. Surveyed woody plants in the community were as follows : Chionanthus retusus, Zelkova serrata, Quercus variabilis, Cornus walteri, Robinia pseudo-acacia and those were mixed status. And Chionanthus retusus, Zelkova serrata, Robinia pseudo-acacia, Albizzia julibrisin, Cudrania tricuspidata, Symplocos chinensis for. pilosa were mixed in mid layer trees. Herbaceous plants were founded such as Chionanthus retusus, Zelkova serrata, Robinia pseudo-acacia, Grewia parviflora, Rosa multiflora, Trachelospermum asiaticum was dominant with 35~64% in the ground cover, and Commelina communis, Calamagrostis arundinacea, Dryopteris bissetiana, Lilium lancifolium were founded also. 5. The importance values of Chionanthus retusus was 40.2% in the quadrat A1, 50.2% at quadrat A, 50.0% B1, 45.2% B2, 22.4% C1, 73.6% C2, 33.2% D1 and the total average of I.V. was 44.9%. 6. The average height of surveyed Chionanthus retusus was 5.7m and the average DBH was 12.4cm. The number of trees higher than 2m were 107 and the number of trees lower than 2m were 63. The total numbers of Chionanthus retusus were 170. 7. The age of surveyed Chionanthus retusus were analyzed 42 thru 87 years old and that of Zelkova serrata were 42, Quercus variabilis were 60, Quercus aliena were 48, Robinia pseudo-acacia were 40. 8. The number of trees with DBH 40 through 50cm were 6, and that of 30~39cm were 3, and that of 20~29cm were 16, so the total number that was over 20cm was 25. And there were 70 trees under 10cm of DBH and 63 seedlings. It will be very important data to conserve the habitat that the structure and environmental condition of the Chionanthus retusus Lindly et Paxton community at the Wansanchielbong was stable, and sustainable monitoring will be needed. Now that community is nurse forest of Jeonju City but more positive preservation plan will be needed and assigning monument of city or province also be necessary.