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Comparison of Three Kinds of Methods on Estimation of Forest Carbon Stocks Distribution Using National Forest Inventory DB and Forest Type Map (국가산림자원조사 DB와 임상도를 이용한 산림탄소저장량 공간분포 추정방법 비교)

  • Kim, Kyoung-Min;Roh, Young-Hee;Kim, Eun-Sook
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.4
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    • pp.69-85
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    • 2014
  • Carbon stocks of NFI plots can be accurately estimated using field survey information. However, an accurate estimation of carbon stocks in other unsurveyed sites is very difficult. In order to fill this gap, various spatial information can be used as an ancillary data. In South Korea, there is the 1:5,000 forest type map that was produced by digital air-photo interpretation and field survey. Because this map contains very detailed forest information, it can be used as the high-quality spatial data for estimating carbon stocks. In this study, we compared three upscaling methods based on the 1:5,000 forest type map and 5th national forest inventory data. Map algebra(method 1), RK(Regression Kriging)(method 2), and GWR(Geographically Weighted Regression)(method 3) were applied to estimate forest carbon stock in Chungcheong-nam Do and Daejeon metropolitan city. The range of carbon stocks from method 2(1.39~138.80 tonC/ha) and method 3(1.28~149.98 tonC/ha) were more similar to that of previous method(1.56~156.40 tonC/ha) than that of method 1(0.00~93.37 tonC/ha). This result shows that RK and GWR considering spatial autocorrelation can show spatial heterogeneity of carbon stocks. We carried out paired t-test for carbon stock data using 186 sample points to assess estimation accuracy. As a result, the average carbon stocks of method 2 and field survey method were not significantly different at p=0.05 using paired t-test. And the result of method 2 showed the lowest RMSE. Therefore regression kriging method is useful to consider spatial variations of carbon stocks distribution in rugged terrain and complex forest stand.

The Agreements between FEV1 and PEFR in the Patients of Mild Bronchial Asthma (외래 진료가 가능한 경증 천식 환자에서 1초간 노력성 호기량(FEV1)과 최대 호기유속(PEFR)간의 연관성)

  • Chang, Won Chul;Kim, Byung Kook;Kim, Soon Jong;Yoo, Kwang Ha;Lee, Tae-Hun;Lee, Jung Yeon;Lee, Kye Young
    • Tuberculosis and Respiratory Diseases
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    • v.59 no.6
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    • pp.638-643
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    • 2005
  • Background : Several studies have shown considerable disagreement when using the $FEV_1$ and PEFR to assess the severity of an airflow obstruction. A differential classification of the severity of asthma would lead to serious differences in the evaluation and management of asthma. The aim of this study was to examine the relationship between the $FEV_1$ and PEFR in asthma patients with mild symptoms. Methods : In this study, the PEFR and $FEV_1$ were obtained from 92 adult asthma patients with mild symptoms attending an outpatient pulmonary clinic. The mean differences and the limits of agreement in the paired measurements of the $FEV_1$ and PEFR were calculated. Results : There was a considerable correlation between the $FEV_1$ and PEFR measurements when expressed as a % of the predicted values (r=0.686, p<0.01). The 95% limit of agreement (mean difference ${\pm}1.96SD$) between the $FEV_1$ % and PEFR % were acceptable(-27.4%~33.8%). In addition, the weighted ${\kappa}$(kappa) coefficient for the agreement between the $FEV_1$ % and PEFR % was 0.74 (95% CI, 0.63-0.81), indicating excellent agreement between the two measurements. Conclusion : The spirometer ($FEV_1$) and the Mini-Wright peak flow meter (PEFR) can be used interchangeably in adult asthma patients with mild symptom.

Economic Impact of the Tariff Reform : A General Equilibrium Approach (관세율(關稅率) 조정(調整) 경제적(經濟的) 효과분석(效果分析) : 일반균형적(一般均衡的) 접근(接近))

  • Lee, Won-yong
    • KDI Journal of Economic Policy
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    • v.12 no.1
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    • pp.69-91
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    • 1990
  • A major change in tariff rates was made in January 1989 in Korea. The benchmark tariff rate, which applies to about two thirds of all commodity items, was lowered to 15 percent from 20 percent. In addition, the variation in tariff rates among different types of commodities was reduced. This paper examines the economic impact of the tariff reform using a multisectoral general equilibrium model of the Korean economy which was introduced by Lee and Chang(1988), and by Lee(1988). More specifically, this paper attempts to find the changes in imports, exports, domestic production, consumption, prices, and employment in 31 different sectors of the economy induced by the reform in tariff rates. The policy simulations are made according to three different methods. First, tariff changes in industries are calculated strictly according to the change in legal tariff rates, which tend to over-estimate the size of the tariff reduction given the tariff-drawback system and tariff exemption applied to various import items. Second, tariff changes in industries are obtained by dividing the estimated tariff revenues of each industry by the estimated imports for that industry, which are often called actual tariff rates. According to the first method, the import-weighted average tariff rate is lowered from 15.2% to 10.2%, while the second method changes the average tariff rate from 6.2% to 4.2%. In the third method, the tariff-drawback system is internalized in the model. This paper reports the results of the policy simulation according to all three methods, comparing them with one another. It is argued that the second method yields the most realistic estimate of the changes in macro-economic variables, while the third method is useful in delineating the differences in impact across industries. The findings, according to the second method, show that the tariff reform induces more imports in most sectors. Garments, leather products, and wood products are those industries in which imports increase by more than 5 percent. On the other hand, imports in agricultural, mining and service sectors are least affected. Domestic production increases in all sectors except the following: leather products, non-metalic products, chemicals, paper and paper products, and wood-product industries. The increase in production and employment is largest in export industries, followed by service industries. An impact on macroeconomic variables is also simulated. The tariff reform increases nominal GNP by 0.26 percent, lowers the consumer price index by 0.49 percent, increases employment by 0.24 percent, and worsens the trade balance by 480 million US dollars, through a rise in exports of 540 million US dollars and a rise in imports of 1.02 billion US dollars.

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Relationship between Environmental Exposure and Biological Monitoring Values in Workers Exposed to Styrene (스타이렌 폭로 근로자의 환경중 폭로농도와 생물학적 모니터링에 관한 연구)

  • Paik, Jong-Min;Lee, Jong-Yung;Kim, Jung-Man
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.7 no.2
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    • pp.161-170
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    • 1997
  • This is an effort to confirm changes biological monitoring according to changes in levels of exposure to styrene for industrial workers. This study was conducted on 108 workers, including male of 64 and female 44 who were working at factories of FRP, dipping, and coating. An improved passive monitor method(organic vapor monitor; OVM) was employed to determine levels of exposure. The biological monitoring include blood styrene concentration, urinary mandelic acid(MA), and urinary phenylglyoxylic acid(PGA). Biological monitoring were made through the Collection of blood and urine. The mean value of exposure to styrene was 21.0ppm, which is measured by organic vapor monitor, one of improved passive monitors. The highest exposure level was observed among workers in boat factories, laminating procedure workers, processing workers, respectively(p<0.01). For exposure level, 11% of subjects under study showed over 50ppm which is time weighted average(TWA). The correlation coefficient between biological specimens and the exposure level was 0.62 for blood styrene concentration, 0.58 for MA corrected by creatinine, and 0.70 for PGA corrected by creatinine, respectively(p<0.01). The regression analyses found exposure level relative importance in explaining variance in biological monitoring. In additional to that, gender was a significant factor in explaining variance of MA and MA+PGA. Almost half of variance(49%) in blood styrene concentration was explained by predictors, including exposure level, age, gender, duration, and drinking volume during the last week(p<0.01). The very high correlation(higher than 0.95 was found when a comparison was made among three types of corrected methods, including uncorrected specific gravity and creatinine. In conclusion, these findings suggest OVM to represent levels of exposure to styrene for industrial workers. A discussion was made on possible use of specific gravity sample for biological monitoring. Exposure level may be predicted on MA, PGA in urine, which could be applied to represent biological monitoring.

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Selection and Application of Evaluation Factors for Urban Regeneration Project (도시재생사업의 평가요인 선정 및 적용)

  • Jang, Cheol-Kyu
    • Journal of the Korean Institute of Landscape Architecture
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    • v.47 no.6
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    • pp.53-66
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    • 2019
  • The purpose of this study was to suggest indicator-based selection and improvement plans for evaluating urban regeneration projects. First, we selected the indicators by conducting expert surveys and analysis of the responses received. Additionally, using the selected indicators, we analyzed the residents' opinions in Wongogae Village, where urban regeneration projects were in progress. Based on these, we suggested a plan to improve Wongogae Village. According to the study, we classified the urban regeneration evaluation indicators into 'Physical environment', 'Social environment' and 'Economic environment' according to their characteristics. We selected urban regeneration evaluation factors through the first expert survey and MCB analysis. As a result, we selected six factors for the 'Physical environment' category: 'Traffic and pedestrian environment', 'Residential (housing) environment', 'Safety and security environment', 'Greenspace', 'Landscape improvement' and 'Public space', In the 'Social environment' category, four factors were chosen: 'Resident participation', 'Community activation', 'Role of the local government and support centers' and 'Resident education' while for the 'Economic environment' category three factors were selected: 'Local economic revitalization', 'Creating an economy-based environment', 'Job creation'. Next, we conducted a second expert survey and carried out an AHP analysis using the selected evaluation factors to derive the overall weight for each. Among the evaluation factors for urban regeneration, the 'Residential (housing) environment' has the highest weighted value of 0.108, followed by 'Local economic revitalization' and 'Resident participation'. Lastly, the analysis of the residents' opinions of Wongogae Village using the urban regeneration evaluation factors, Parking environment', 'Maintenance of old houses and living environment', 'Environment for founding town and social enterprises', 'Improve commercial and business environment', 'Maintain and activate existing business' and 'Vitalizing small regional economies such as domestic handicrafts and side-job' had high overall importance, but low satisfaction, which means that it is necessary to improve the focus. Therefore, in order to improve the urban regeneration project in villages, it is necessary to improve the parking environment by expanding public parking lots, eliminate close houses, and idle lands, or open a school playground in the village for the residents. In addition, it is essential to encourage economic activities, such as fostering village enterprises and social enterprises in connection with cooperatives and allow for the selling of the products through resident activities, such as neighboring markets.

Associations between the Practice of Health Behaviors and Awareness of Metabolic Syndrome among Adults (19-64 years) in the Gwangju-Jeonnam Area: 2010 Community Health Survey (광주 전남지역 성인의(19-64세) 건강생활실천과 대사증후군 인지와의 관련성 - 2010년 지역사회건강조사 자료를 이용하여 -)

  • Chun, In Ae;Ryu, So Yeon;Park, Hyeon Hui;Park, Jong;Han, Mi Ah;Choi, Seong Woo
    • Journal of agricultural medicine and community health
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    • v.38 no.4
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    • pp.217-228
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    • 2013
  • Objective: This study was performed to identify associations between the practice of health behaviors and awareness of metabolic syndrome (MetS) among adults aged 19 to 64 years in the Gwangju-Jeonnam area. Methods: This study utilized data from the 2010 Community Health Survey (CHS). Health behaviors considered in this study were smoking, alcohol drinking, physical activity, low-salt diet, and perception of stress. The index for the health behaviors was calculated as the sum of the practice of each health behavior (range: 0-5). The analysis was weighted with a complex sampling design, and the chi-square test and multiple logistic regression analysis were used to identify the association between the practice of health behaviors and awareness of MetS. Results: A total of 19.8% of the population were aware of MetS. The perception of MetS was statistically significantly associated with healthy behaviors, including nonsmoking (aOR = 1.33, 95% CI = 1.14-1.56), non-high-risk drinking (aOR = 1.54, 95% CI = 1.27-1.88), engagement in physical activity (aOR = 1.48, 95% CI = 1.28-1.72), and a low-salt diet (aOR = 1.30, 95% CI = 1.13-1.51). The ORs of the perception of MetS were significantly higher in patients with a health behavior index of 2 to 3 (aOR = 1.64, 95% CI = 1.01-2.66) and in those with an index of ${\geq}4$ (aOR = 2.47, 95% CI = 1.51-4.04) than in those with an index of 0. Among all health behaviors, physical activity had the highest OR for the perception of MetS (aOR = 1.50, 95% CI = 1.29-1.74). Conclusions: This study revealed associations between health behaviors, especially physical activity, and awareness of MetS. Therefore, integrated health promotion programs may be needed to enhance awareness of MetS and to effectively prevent MetS and non-communicable diseases.

M2 Velocity and Expected Inflation in Korea: Implications for Interest Rate Policy (인플레와 M2 유통속도(流通速度))

  • Park, Woo-kyu
    • KDI Journal of Economic Policy
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    • v.13 no.2
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    • pp.3-19
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    • 1991
  • This paper attempts to identify key determinants of long run movements of real M2 by using the Johansen procedure for estimating and testing cointegration relations. It turns out that the real M2 equation has been stable over the long run despite rapid changes in financial structure since 1975. Moreover, the real M2 equation can be reduced to a velocity equation with the opportunity cost variable, expected inflation less the weighted average rate paid on M2 deposits, being the key determinant. However, it does not work to use a market interest rate such as the yield on corporate bonds in place of expected inflation for calculation of the opportunity cost. In the U.S., a market interest rate can be used, but not in Korea. Presumably, two somewhat different reasonings can be used to explain this result. One is that the yield on corporate bonds may not adequately reflect the inflationary expectations due to regulations on movements in interest rates. The other is that M2 deposits are not readily substitutable with such assets as corporate bonds because of market segmentations, regulations, and so on. From the policymaker's point of view, this implies that the inflation rate is an important indicator of a policy response. On the other hand, policymakers do not regard movements of the yield on corporate bonds as an important policy indicator. Altogether, the role of interest rates has been quite limited in Korea because of incomplete interest rate liberalization, an underdeveloped financial system, implementation procedures of policy measures, and so on. The result that M2 velocity has a positive cointegration relation with expected inflation minus the average rate on M2 implies that frequent adjustments of the regulated rates on M2 will be necessary as market conditions change. As the expected inflation gets higher, M2 velocity will eventually increase, given that the rates on M2 do not change. This will cause higher inflation. If interest rates are liberalized, then increases in market interest rates will result in lagged increases in deposits rates on M2. However, in Korea a substantial portion of deposit rates are regulated and will not change without the authority's initiatives. A tight monetary policy will cause increases in a few market interest rates. But the market mechanism, upward pressure for interest rate adjustments, never reaches regulated deposit rates. Hence the overall effects of tight monetary policy diminish considerably, only causing distortions in the flow of funds. Therefore, frequent adjustments of deposit rates are necessary as market conditions such as inflationary expectations change. Then it becomes important for the policymaker to actively engage in adjusting regulated deposit rates, because the financial sector in Korea is not fully developed.

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Usefulness of Registration in the Evaluation of Parkinson′s Disease (영상 융합하여 분석한 파킨슨씨병 환자영상의 유용성)

  • 주라형;김재승;문대혁;최보영;서태석
    • Progress in Medical Physics
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    • v.14 no.4
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    • pp.268-278
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    • 2003
  • Purpose:The aim of this study was to evaluate the striatal binding ratio, the anterior/posterior ratio and reproducibility using a template based registration method using the standard MR template as a replacement for each patients MR image. Materials and Methods:This study analyzed the 123I IPT SPECT images of 30 patients with IPD, who were subdivided into 17 patients (56.6$\pm$10.8 yr, M/F : 8/9.) with mild IPD, and 13 patients (56.4$\pm$11.1 yr, M/F : 8/5) with severe IPD. In addition, 11 normal controls (57.8$\pm$14.4 yr, M/F : 4/7) were also analyzed. The ROIs were positioned manually in the same slice showing the highest striatal activity using the traditional manual method, whereas those were positioned automatically in a mid striatal slice of the SPECT image coregistered to the standard T1 weighted MR template. Results : The specific binding ratio (SBR) obtained using the template based registration method strongly correlated with those using the manual method in all groups : normal controls (r=0.85, P<0.001), mild IPD (r=0.84, P<0.001) and severe IPD (r=0.7, P=0.01). The SBRs obtained using both methods were significantly different among the three groups (P=0.05) and the SBRs obtained by the template based registration method were higher than those by the manual method (P=0.05) in all three groups. The APRs obtained by the template based registration correlated with those using manual method in only mild IPD (r=0.72, P=0.0). The APRs obtained by the template based registration method were significantly different from the normal controls and those with mild or severe IPD (P<0.05), whereas those obtained using the manual method were not significantly different among the three groups (P>0.1). The reproducibility (rmsCV) of the template based registration method was 7.2% (normal controls:5.2%, mild IPD:4.2%, severe IPD:10.8%), whereas the reproducibility of the manual method was 31% (normal controls:19.7%, mild IPD:21.7%, severe IPD:46.2%). Conclusion:These results show that the use of $^{123}$ I-IPT SPECT for assessing IPD is affected by the methods used to position the striatal ROI. The template based registration method using the standard MR template can be useful in diagnosing IPD and assessing the disease severity with a high reproducibility. Therefore, the template based registration method appears to be a good replacement for the manual method.

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The Clinical Characteristics According to the Risk Factors of Idiopathic Nonhemolytic Hyperbilirubinemia (신생아 특발성 비용혈성 고빌리루빈혈증의 위험 요인에 따른 임상 양상)

  • Park, Sook-Hyun;Kang, Ji-Hyun;Kwon, Soon-Hak;Kim, Heng-Mi;Kim, Yong-Sun
    • Neonatal Medicine
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    • v.17 no.2
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    • pp.224-231
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    • 2010
  • Purpose: Hospital readmissions have recently increased due to early hospital discharge and increased trends in breast-feeding. Neonatal hyperbilirubinemia can lead to fatal permanent neurological sequelae without appropriate management. Early detection and intervention are critical. We evaluated the clinical features, risk factors, and brain MRI findings of Korean newborns with idiopathic nonhemolytic hyperbilirubinemia to determine the optimal management policy. Methods: A retrospective review of the medical records of 79 newborns with idiopathic nonhemolytic hyperbilirubinemia was performed at the NICU of the Kyungpook National University Hospital from January 2006 to September 2009. All patients were 35 or more weeks of gestation, and their peak level of serum total bilirubin was more than 20 mg/dL. Results: The mean gestational age was $38^{+3}{\pm}1^{+4}$ weeks, and the mean age on admission was 8.8$\pm$4.0 days. The mean body weight (3,105$\pm$479 g) was decreased by 2.8$\pm$6.4 percent compared to the mean birth weight (3,174$\pm$406 g). There were no statistically significant differences for the peak serum bilirubin level or the duration and effects of phototherapy between the patients with and without risk factors, which included: breastfeeding, cephalohematoma, subdural hemorrhage, and/or ABO incompatibility. Patients were grouped according to change of body weight. Group I consisted of patients that gained weight compared to birth weight, and group II of patients that lost weight compared to birth weight. There were significant differences in the peak serum total bilirubin level between the two groups. Thirty nine patients had brain MRI evaluation; 21 patients had bilateral symmetric signal intensity increases in the globus pallidus compared to adjacent corticospinal tract and putamen on T1-weighted images. Conclusion: Bilirubin encephalopathy is preventable with early screening and proper management. Parents require instruction on feeding practices and follow-up to prevent complications from idiopathic nonhemolytic hyperbilirubinemia.

Quantification of Brain Images Using Korean Standard Templates and Structural and Cytoarchitectonic Probabilistic Maps (한국인 뇌 표준판과 해부학적 및 세포구축학적 확률뇌지도를 이용한 뇌영상 정량화)

  • Lee, Jae-Sung;Lee, Dong-Soo;Kim, Yu-Kyeong;Kim, Jin-Su;Lee, Jong-Min;Koo, Bang-Bon;Kim, Jae-Jin;Kwon, Jun-Soo;Yoo, Tae-Woo;Chang, Ki-Hyun;Kim, Sun-I.;Kang, Hye-Jin;Kang, Eun-Joo
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.3
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    • pp.241-252
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    • 2004
  • Purpose: Population based structural and functional maps of the brain provide effective tools for the analysis and interpretation of complex and individually variable brain data. Brain MRI and PET standard templates and statistical probabilistic maps based on image data of Korean normal volunteers have been developed and probabilistic maps based on cytoarchitectonic data have been introduced. A quantification method using these data was developed for the objective assessment of regional intensity in the brain images. Materials and Methods: Age, gender and ethnic specific anatomical and functional brain templates based on MR and PET images of Korean normal volunteers were developed. Korean structural probabilistic maps for 89 brain regions and cytoarchitectonic probabilistic maps for 13 Brodmann areas were transformed onto the standard templates. Brain FDG PET and SPGR MR images of normal volunteers were spatially normalized onto the template of each modality and gender. Regional uptake of radiotracers in PET and gray matter concentration in MR images were then quantified by averaging (or summing) regional intensities weighted using the probabilistic maps of brain regions. Regionally specific effects of aging on glucose metabolism in cingulate cortex were also examined. Results: Quantification program could generate quantification results for single spatially normalized images per 20 seconds. Glucose metabolism change in cingulate gyrus was regionally specific: ratios of glucose metabolism in the rostral anterior cingulate vs. posterior cingulate and the caudal anterior cingulate vs. posterior cingulate were significantly decreased as the age increased. 'Rostral anterior'/'posterior' was decreased by 3.1% per decade of age ($P<10^{-11}$, r=0.81) and 'caudal anterior'/'posterior' was decreased by 1.7% ($P<10^{-8}$, r=0.72). Conclusion: Ethnic specific standard templates and probabilistic maps and quantification program developed in this study will be useful for the analysis of brain image of Korean people since the difference in shape of the hemispheres and the sulcal pattern of brain relative to age, gender, races, and diseases cannot be fully overcome by the nonlinear spatial normalization techniques.