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$^{18}F$-FDG PET/CT in Patients with Initially Diagnosed Adenoid Cystic Carcinoma of the Head and Neck: Clinicoplathologic Correlation (처음 진단된 두경부 선양낭성암종에서 $^{18}F$-FDG PET/CT: 임상상 및 병리소견과의 상관성)

  • Lee, Ji-Young;Choi, Joon-Young;Ko, Young-Hyeh;Baek, Chung-Hwan;Son, Young-Ik;Cho, Suk-Kyong;Cheon, Mi-Ju;Lee, Kyung-Han;Kim, Byung-Tae
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.5
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    • pp.395-401
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    • 2009
  • Purpose: We evaluated $^{18}F$-FDG PET/CT findings in initially diagnosed adenoid cystic carcinoma (ACC) of the head and neck in association with pathological subtype, staging, uptake comparison with squamous cell carcinoma (SqCC) and prognosis. Materials and Methods: The subjects were 16 patients with initially diagnosed ACC of head and neck who underwent pretreatment $^{18}F$-FDG PET/CT. Histological subtype (solid pattern vs. tubular/cribriform pattern), $SUV_{max}$ of size-matched SqCC of the head and neck as control group, disease-free survival (DFS) were compared with the $SUV_{max}$ of ACC of the head and neck. Results: Of total 16 patients, 6 had solid pattern and the remaining 10 had tubular/cribriform pattern. The $SUV_{max}$ were significantly higher in solid pattern group than in tubular/cribriform pattern group ($6.7{\pm}3.2$ vs. $4.2{\pm}0.9$, p=0.03). PET/CT found unexpected distant metastasis in 18.7% of patients (3/16) and changed the therapeutic plan in those patients. The $SUV_{max}$ of ACC was significantly lower than that of size-matched SqCC ($5.1{\pm}2.4$ vs. $13.6{\pm}6.0$, p<0.001). DFS was not significantly different according to the histological subtype. In contrast, patients with high $^{18}F$-FDG uptake ($SUV_{max}$ ${\geq}$6.0) had significantly shorter DFS than those with low $^{18}F$-FDG uptake ($SUV_{max}$ <6.0). Conclusion: $^{18}F$-FDG uptake of ACC of the head and neck is significantly associated with histological subtype and DFS. $^{18}F$-FDG PET/CT may be useful for detecting unexpected metastasis. Since $^{18}F$-FDG uptake of tubular/cribriform ACC compared with SqCC is relatively low, it is necessary to interpret PET images carefully in patients without alleged ACC.

Abosrbed Dose Measurements and Phantom Image Ecaluation at Minimum CT Dose for Pediatric SPECT/CT Scan (소아 SPECT/CT 검사를 위한 최저조건에서의 피폭선량측정 및 팬텀의 영상평가)

  • Park, Chan Rok;Choi, Jin Wook;Cho, Seong Wook;Kim, Jin Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.82-88
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    • 2014
  • Purpose: The purpose of study was to evaluate radiation dose for pediatric patients by changing tube voltage (kVp) and tube current (mA) at minimum conditions. By evaluating radiation dose, we want to provide dose reduction for pediatric patients and maintain good quality of SPECT/CT images. Materials and Methods: Discovery NM/CT 670 Scanne was used as SPECT/CT. Tube voltages are 80 and 100 kvP. Tube currents are 10, 15, 20, 25 mA. Using PMMA (Polymethyl methacrylate) Phantom, radiation dose which were calculated at center and peripheral dose and SNRD (Signal to Noise Ratio Dose) were evaluated. Using the CT performance phantom, spatial resolution was evaluated as the MTF (Modulation Transfer Function) graph. Jaszczak phantom was used for SPECT image evaluation by CNR (Contrast to Noise to Ratio). Results: Radiation dose using the PMMA phantom was higher peripheral dose than center dose about 7%. SNRD were 7.8, 8.2, 8.3, 8.8, 8.8, 9.9, 9.8, 9.6 for 80 kVp 10, 15, 20, 25 mA, 100 kVp 10, 15, 20, 25 mA. We can distinguish 35, 45, 70, 71, 52, 58, 90, 110 linepair for 80 kVp 10, 15, 20, 25 mA, 100 kVp 10, 15, 20, 25 mA at resolution with MTF. CNR of SPECT images using CT attenuation map were 57.8, 57.7, 57.1, 56.7, 56.6, 56.7, 56.7, 56.7% for 80 kVp 10, 15, 20, 25 mA, 100 kVp 10, 15, 20, 25 mA. Conclusion: In this study, radiation dose for pediatric patients showed decreased low dose condition. And SNRD value was similar in all condition. Resolution showed higher value at 100kVp than 80kVp. for CNR, there was no significant difference. we should take additional study to prove better quality and dose reduction.

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Phytoplankton and Bacterioplankton in the Intertidal and Subtidal Waters in the Vicinity of Kunsan (군산부근 조간대 및 조하대역에서의 식물플랑크톤과 Bacterioplankton)

  • Lee, Won Ho;Lee, Gean Hyoung;Choi, Moon Sul;Lee, Da Mi
    • 한국해양학회지
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    • v.24 no.3
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    • pp.157-164
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    • 1989
  • Quantitative species distribution and primary productivity of phytoplankton were studied monthly from August, 1987 to July, 1988 along with the quantitative distribution of total heterotrophic bacterioplankton and three groups of physiologically chracteristic bacterioplankton in the intertidal and subtidal waters off Kum River Estuary, Yellow Sea. A total of 121 phytoplankton taxa including 102 diatoms occurred, and cell concentration ranged from 15 to 5451 (cells/ml). The great spatio-temporal variations of the number of phytoplankton species and cell concentration well reflected the environmental differences between the intertidal and subtidal waters. Primary productivity (in Piopt, mgC/$m^3$/hr) ranged from 0.6 to 27.3. Just after the phytoplankton bloom (March) Piopt was very low in April at station 1, where amylolytic bacterioplankton also showed quite low population density. The peaks of primary productivity were not always coincided with those of phytoplankton standing crop. The ratio of Piopt's between samples well indicated the environmental differences between the intertidal and subtidal waters. Little characteristic trend was found in the scatter diagrams of phytoplankton standing crop along the population densities of total heterotrophic bacterioplankton and the three groups of physiologically characteristic bacterioplankton. In summer the phytoplankton standing crop was minimum in contrast with the high population density of bacterioplankton, which implies the influx of much allochthonous orgainc matter from Kum River. The scatter diagrams of Piopt along bacterioplankton population density revealed some phenomena there. Piopt had highly positive correlation with the population density of amylolytie bacterioplankton($R^2$=0.84) and that of lipolytic bacterioplankton($R^2$=0.70) while total heterotrophic bacterioplankton and proteolytic bacterioplankton had lesser correlations with Piopt. From the regression lines the increase of unit Piopt (mgC/$m^3$/hr) in the study area was calculated to mean the increase of $9.0{\times}10$ cells/ml and $8.0{\times}10$ cells/ml of amylolytic bacterioplankton and lipolytic bacterioplankton, respectively.

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Study on Nucleation and Evolution Process of Ge Nano-islands on Si(001) Using Atomic Force Microscopy (AFM을 이용한 Si (001) 표면에 Ge 나노점의 형성과 성장과정에 관한 연구)

  • Park, J.S.;Lee, S.H.;Choia, M.S.;Song, D.S.;Leec, S.S.;Kwak, D.W.;Kim, D.H.;Yang, W.C.
    • Journal of the Korean Vacuum Society
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    • v.17 no.3
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    • pp.226-233
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    • 2008
  • The nucleation and evolution process of Ge nano-islands on Si(001) surfaces grown by chemical vapor deposition have been explored using atomic force microscopy (AFM). The Ge nano-islands are grown by exposing the substrates to a mixture of gasses GeH4 and H2 at pressure of 0.1-0.5Torr and temperatures of $600-650^{\circ}C$. The effect of growth conditions such as temperature, Ge thickness, annealing time on the shape, size, number density, and surface distribution was investigated. For Ge deposition greater than ${\sim}5$ monolayer (ML) with a growth rate of ${\sim}0.1ML/sec$ at $600^{\circ}C$, we observed island nucleation on the surface indicating the transition from strained layer to island structure. Further deposition of Ge led to shape transition from initial pyramid and hut to dome and superdome structure. The lateral average size of the islands increased from ${\sim}20nm$ to ${\sim}310nm$ while the number density decreased from $4{\times}10^{18}$ to $5{\times}10^8cm^{-2}$ during the shape transition process. In contrast, for the samples grown at a relatively higher temperature of $650^{\circ}C$ the morphology of the islands showed that the dome shape is dominant over the pyramid shape. The further deposition of Ge led to transition from the dome to the superdome shape. The evolution of shape, size, and surface distribution is related to energy minimization of the islands and surface diffusion of Ge adatoms. In particular, we found that the initially nucleated islands did not grow through long-range interaction between whole islands on the surface but via local interaction between the neighbor islands by investigation of the inter-islands distance.

Antimutagenic and Cytotoxic Effects of Extracts of Kalopanax pictus NAKAI Endodermis (음나무 내피 추출물의 항돌연변이원성 및 세포독성 효과)

  • Kim, Myong-Jo;Kim, Ju-Sung;Kang, Won-Hee;Yeon, Kyu-Dong
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.2
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    • pp.132-138
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    • 2002
  • This study was performed to determine the antimutagenic and cytotoxic effect of ,Kalopanacis cortex endothelium. Methanol extract was used on Salmonella typhimurium TA98, TA100 and three cancer cell lines. In the Ames test, methanol extract of Kalopanacis cortex endothelium alone did not exhibit any mutagenicity but showed substantial inhibitory effects against mutation induced by 4-nitroquinoline-l-oxide(4NQO), N'-methyl- N'-nitro-N-nitrosoguanidine(MNNG) and benzo(a)pyrene(B(a)P). The methanol extract of Kalopanacis cortex endothelium showed approximately 79.29% and 75.38% inhibitory effect on the mutagenesis induced by 4NQO and B(a)P, respectively, against TA98 strain. Whereas 79.49%, 89.3% and 68.85% inhibitions were observed on the mutagenesis induced by 4NQO, MNNG and B(a)P against TA100 strain. Methanol extracts from Kalopanacis cortex endothelium showed high antimutagenic effects against 4NQO, MNNG and B(a)P. The anticancer effects of methanol extract from Kalopanacis cortex endothelium against human lung carcinoma(A549), human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma(Hep3B) were investigated. The treatment of 0.5mg/ml Kalopanacis cortex endothelium methanol extracts had the highest cytotoxicity against A549(81.54%), followed by MCF-7(81.92%) and Hep3B (78.57%). In contrast 0.5mg/ml treatment of methanol extracts from Kalopanacis cortex endothelium had only $4{\sim}25%$ cytotoxicity on normal human liver cell(293).

Life Experiences of Middle School Students from Broken Homes (결손가정 중학생의 생활경험)

  • Choe, Gee-Hyun;Chung, Yeon-Kang;Yeoum, Soon-Gyo
    • Journal of the Korean Society of School Health
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    • v.10 no.2
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    • pp.271-283
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    • 1997
  • This study is designed for the school health education, contributing experience of life from middle school students from broken homes by describing specifically what they go through. And on this basis this study works out a grounded theory on the experience of life for middle school students from broken homes. The data was collected through a series of interviews with nine subjects singled out at each stage of research. With the permission of the subjects, the interviews were recorded and transcribed. The interviews lasted from 30 minutes up to one hour and 20 minutes. The in-depth interviewing methods and observations was used for data collection. The data was analyzed in the framework of grounded theory as mapped out by Strauss & Corbin (1990). By analyzing the materials eighty-three concepts were extracted, and they were united into 21 subordinate categories through the course of analysis. These were classified into nine precedence categories. The core category was found to be the adaptation of 'Wichookdem" or "Shrinkage". "Shrinkage" widows experienced was showed as the results "Self-reliance" and "Overcoming" through the course of generation and reaction, confrontation, and adaptation. According to the analysis findings of materials, the central phenomenon was showed as "shrinkage", the causal condition as "surprise", "Darkness", "Grudge", "Desolate", "Empty". The veins as presence of those around people and existence of support, and the meditate situation as self-support. For the strategy in solving "shrinkage", preparations of countermeasure and self-reinforcement were showed. And self-reliance and overcoming were the results. Through the contrast to the cases of ground materials, relation statements as follows were induced; (1) The weaker the suffering is, the weaker the "shrinkage" tends to be. (2) The stronger the suffering is, the stronger the "shrinkage" tends to be. (3) The more frequent and serious the suffering, the stronger the "shrinkage" tend to be. (4) The more infrequent and not serious the suffering is, the weaker the "shrinkage" tends to be. (5) The weaker the "shrinkage" is, the more self-control1ed the responses tends to be. (6) The stronger the "shrinkage" is, the more impulsive the responses tends to be. (7) The more satisfying the support is, the more self-controlled the responses to the "shrinkage" tends to be. (8) The more dissatisfying the support is, the more impulsive the responses to the "shrinkage" tends to be. (9) The more concrete the type of support is, the more self-controlled the responses to the "shrinkage" tends to be. (10) The more superficial the type of support is, the more impulsive the responses to the "shrinkage" tends to be. (11) The more self-controlled the responses are, the more self-reliant the subjects tends to be. (12) The more impulsive the responses are, the more conflict and wandering the subjects tends to be. (13) Whether the responses to the "shrinkage" express themselves in self-control or an impulse, it will be resulted in the form of either tension or pain. The following two were confirmed on the basis of repetitive relations; (1) If a subject's suffering is weak, infrequent and not serious, the "shrinkage" is weak. Also the subject's support is highly satisfying, and the support type is concrete. The responses to the "shrinkage" result in self-control which consequence is self-reliance with part. of it resulting in tension and pain. (2) If a subject's suffering is strong, frequent and serious, the "shrinkage" is strong. Also the subject's support is dissatisfying, and the support type is superficial. The responses to the "shrinkage" result in an impulsion whose consequence is wandering with part of it resulting in tension and pain. Through the results in this study, the following is to be suggested; O This research is basically aimed at analyzing the experience of the middle school students living in broken homes, for the more inclusive approach, the study for them is made systematically according to the type of their problems.

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Damage and biological control of dark winged fungus gnats, Lycoriella ingenua (Diptera: Sciaridae) in a shiitake cultivation (표고 톱밥재배에서 검정날개버섯파리 Lycoriella ingenua (Diptera: Sciaridae)의 피해와 생물적 방제)

  • Kim, Hyeong-Hwan;Cho, Myoung-Rae;Kang, Taek-Jun;Ahn, Seung-Joon;Jeon, Sung-Wook;Lee, Chan-Jung;Cheong, Jong-Chun
    • Journal of Mushroom
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    • v.10 no.4
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    • pp.184-190
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    • 2012
  • Monitorings and management experiment of adult Lycoriella ingenua (Diptera: Sciaridae) in artificial sawdust grown shiitake mushroom cultivation were carried out by using yellow sticky traps and Hypoaspis aculeifer (Acari: Laelapidae) at Hwaseong, Buyeo and Cheongwon in 2012. The larvae of L. ingenua reduced commercial value of the mushroom by direct eating or retarding the growth of mushroom by spongifying the sawdust medium. The number of L. ingenua caught by traps showed the highest peak in late september resulting in 127.5~1,025.7, 87.4~743.6 and 133.7~650.4 individuals per trap in Hwaseong, Buyeo and Cheongwon, respectively. Damage rate of fruiting bodies in shiitake mushroom by L. ingenua were 7.7~30.3% in Hwaseong, 6.7~25.3% in Buyeo and 5.3~26.0% in Cheongwon and showed the highest peak in late september. L. ingenua were effectively controlled when 30.3 individuals of H. aculeifer per $m^2$ inoculated for three time with 7 to 14 days of interval. In Hwaseong, Buyeo and Cheongwon, density of L. ingenua which were caught on the yellow sticky traps were 168.2, 126.1, 132.5 individuals, respectively. And, damage rate of fruiting bodies by L. ingenua were 5.9%, 5.5% and 5.4% respectively. Both of the L. ingenua density and damage rate of mushroom reduced more than 60% in all experimental site in contrast to the control treatment.

A Study of the Utilization of Feldspathic Sand as a Fortified Functional Filtering Material for Water Purification (고 기능성 수질 정화 여과재로서의 장석질 모래 활용연구)

  • 고상모;송민섭;홍석정
    • Journal of the Mineralogical Society of Korea
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    • v.16 no.4
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    • pp.283-293
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    • 2003
  • Domestic water treatment plants operate the rapid and slow filtering system using the filtering sands. Most of them are composed of beach sands, which have less sorption capacity of heavy metals as well as organic contaminants. Therefore, the development of fortified functional filtering materials with high removal capacity of organic and inorganic contaminants is needed to prevent the unexpected load of contaminated source water. This study aims to test the hydrochemical change and the removing capacity of heavy metals such as Cd, Cu, and Pb on the Jumunjin sand, feldspathic sand(weathering product of Jecheon granite), feldspathic mixing sand I(feldspathic sand mixed with 10 wt% zeolite), and feldspathic mixing sand II (feldspathic sand mixed with 20 wt% zeolite). Feldspathic mixing sand I and II showed the eruption of higher amounts of cations and anions compared with the Jumunjin sand and feldspathic sand. They also showed higher eruption of Si, Ca, $SO_4$ ions than that of Al, $NO_3$, Fe, K, Mg, and P. Feldspathic mixing sand II caused higher eruption of some cations of Na, Ca, Al than feldspathic mixing sud I, which is the result controlled by the dissolution of zeolite. Jumunjin sand and feldspathic sand showed very weak sorption of Cd, Cu and Pb. In contrast to this, feldspathic mixing sand I and II showed the high sorption and removal capacity of the increasing order of Cd, Cu and Pb. Feldspathic mixing sand II including 20% zeolite showed a fortified removal capacity of some heavy metals. Therefore, feldspathic mixing sand mixed with some contents of zeolite could be used as the fortified filtering materials for the water filtering and purification in the domestic water treatment plants.

Chemical Characteristics for Hydrothermal Alteration of Surface Sediments from Submarine Volcanoes of the Tonga Arc (통가열도 해저화산 표층 퇴적물 내 열수변질의 화학적 특성)

  • Um, In Kwon;Chun, Jong-Hwa;Choi, Hunsoo;Choi, Man Sik
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.4
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    • pp.245-262
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    • 2013
  • We analyzed 29 surface sediment samples in five submarine volcanoes (TA12, TA19, TA22, TA25, and TA26) located in the southern part of the Tonga arc for trace elements and rare earth elements to investigate characteristics of the hydrothermal alteration of surface sediments. Based on analytical results of trace element and rare earth element (REE), surface sediments of TA12, TA19, and TA22 submarine volcanoes, which are located in the northern part of the study area, were very little or not influenced by hydrothermal fluids. In contrast, some stations of TA25 and TA26 submarine volcanoes were strongly affected by hydrothermal fluids. However, these two submarine volcanoes showed different features in element concentration in the sediments. Some stations of TA25 submarine volcano showed enrichment of Ni, Cu, Sn, Zn, Pb, Cr, Cd, Sb, W, Ba, Ta, Rb, Sr, and As, however, those of TA26 submarine volcano showed enrichment of Sn, Zn, Pb, Cd, Sb, Ba, Rb, and Sr. Stations which enriched trace elements were observed, enriched REEs were also observed. Average upper continental crust (UCC)-normalized REE patterns of the surface sediments generally showed low light REE (LREE) abundances and increased heavy REE (HREE) abundances. Eu enrichment was identified at several stations of TA25 and TA26 submarine volcanoes. In addition, enrichment of Ce was found at some stations of TA26 submarine volcano and these enrichment patterns were similar with hydrothermal fluid of near stations. Furthermore, TA25 and TA26 submarine volcanoes showed different enrichment characteristics of trace elements and REE. Trace elements were concentrated at TA25 submarine volcano. TA26 submarine volcano, on the other hand, observed highly enrichment of REE especially, Eu and Ce. As a result of the investigation, the characteristics and concentrations of REEs and trace elements in the surface sediments of each submarine volcano can be applied to identify hydrothermal alteration of sediments during exploration for hydrothermal deposits.

Analysis of Effect of Environment on Growth and Yield of Autumn Kimchi Cabbage in Jeonnam Province using Big Data (빅데이터를 활용한 재배환경이 전라남도 지방 가을배추의 생육과 수량에 미치는 영향 분석)

  • Wi, Seung Hwan;Lee, Hee Ju;Yu, In Ho;Jang, YoonAh;Yeo, Kyung-Hwan;An, Sewoong;Lee, Jin Hyoung
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.22 no.3
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    • pp.183-193
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    • 2020
  • This study was conducted to evaluate the effect of environment factors on the growth of autumn season cultivation of Kimchi cabbage using the big data in terms of public open data(weather, soil information, and growth of crop, etc.). The growth data and the environment data such as temperature, daylength, and rainfall from 2010 to 2019 were collected. As a result of composing the correlation matrix, the height and leaf number showed high correlation in growing degree days(GDDs) and daylength, and the yield showed negative correlation in growing degree days and the concentration of clay. GDDs and daylength explained about 89% and 84% of variation in height, respectively. These two environmental factors also explained about 85% and 79% of variation in leaf numbers, respectively. In contrast, the coefficient of determination was low for yield when GDDs and concentration of clay was used. The outcome of regional statistical analysis indicated that relationship between yield and sum of sand and silt were high in Haenam and Jindo areas. Hierarchical cluster analysis, which was performed to verify the association of yield, GDDs, and concentration of clay, showed that Haenam and Jindo were clustered together. Although GDDs and yield vary by year and region, and there are regions with similar concentration of clays, observation data are grouped as the result. These suggests that GDDs and soil texture are expected to be related to yield. The cluster analysis results can be used for further data analysis and agricultural policy establishment.