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A study on urban heat islands over the metropolitan Seoul area, using satellite images (원격탐사기법에 의한 도시열섬 연구)

  • ;Lee, Hyoun-Young
    • Journal of the Korean Geographical Society
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    • v.40
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    • pp.1-13
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    • 1989
  • The brightness temperature from NOAA AVHRR CH 4 images was examined for the metropolitan Seoul area, the capital city of Korea, to detect the characteristics of the urban heat island for this study. Surface data from 21 meteorological stations were compared with the brightness temperatures Through computer enhancement techniques, more than 20 heat islands could be recognized in South Korea, with 1 km spatii resolution at a scale of 1: 200, 00O(Fig. 3, 4 and 6). The result of the analysis of AVHRR CH 4 images over the metropolitan Seoul area can be summerized as follows (1) The pattern of brightness temperature distribution in the metropolitan Seoul area shows a relatively strong temperature contrast between urban and rural areas. There is some indication of the warm brightness temperature zone characterrizing built-up area including CBD, densely populated residential district and industrial zone. The cool brightness temperature is asociaed with the major hills such as Bukhan-san, Nam-san and Kwanak-san or with the major water bodies such as Han-gang, and reservoirs. Although the influence of the river and reservoirs is obvious in the brightness temperauture, that of small-scaled land use features such as parks in the cities is not features such as parks in the cities is not apperent. (2) One can find a linerar relationshop between the brightenss temperature and air temperature for 10 major cities, where the difference between two variables is larger in big cities. Though the coefficient value is 0.82, one can estimate that factors of the heat islands can not be explained only by the size of the cities. The magnitude of the horizontal brightness temperature differences between urban and rural area is found to be greater than that of horizontal air temperature difference in Korea. (3) Also one can find the high heat island intensity in some smaller cities such as Changwon(won(Tu-r=9.0$^{\circ}$C) and Po-hang(Tu-r==7.1$^{\circ}$~)T. he industrial location quotient of Chang-won is the second in the country and Po-hang the third. (4) A comparision of the enhanced thermal infrared imageries in 1986 and 1989, with the map at a scale of 1:200, 000 for the meotropolitan Seoul area showes the extent of possible urbanization changes. In the last three years, the heat islands have been extended in area. zone characterrizing built-up area including (5) Although the overall data base is small, the data in Fig. 3 suggest that brightness tempeautre could ge utilized for the study on the heat island characteristics. Satellite observations are required to study and monitor the impact of urban heat island on the climate and environment on global scale. This type of remote sensing provides a meams of monitoring the growth of urban and suburban aeas and its impact on the environment.

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Development of KD- Propeller Series using a New Blade Section (새로운 날개단면을 이용한 KD-프로펠러 씨리즈 개발)

  • J.T. Lee;M.C. Kim;J.W. Ahn;H.C. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.2
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    • pp.52-68
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    • 1991
  • A new propeller series is developed using the newly developed blade section(KH18 section) which behaves better cavitation characteristics and higher lift-drag ratio at wide range of angle-of-attack. The pitch and camber distributions are disigned in order to have the same radial and chordwise loading distribution with the selected circumferentially averaged wake input. Since the geometries of the series propeller, such as chord length, thickness, skew and rate distribations, are selected by regression of the recent full scale propeller geometric data, the performance prediction of a propeller at preliminary design stage can be mure realistic. Number of blades of the series propellers is 4 and the expanded blade area ratios are 0.3, 0.45, 0.6 and 0.75. Mean pitch ratios are selected as 0.5, 0.65, 0.8, 0.75 and 1.1 for each expanded area ratio. The new propeller series is composed of 20 propellers and is named as KD(KRISO-DAEWOO) propeller series. Propeller open water tests are performed at the experimental towing tank, and the cavitation observation tests and fluctuating pressure measurements are carried out at the cavitation tunnel of KRISO. $B_{P}-\delta$ curves, which can be used to select the optimum propeller diameter at the preliminary design stage, are derived from a regression analysis of the propeller often water test results. The KD-cavitation chart is derived from the cavitation observation test results by choosing the local maximum lift coefficient and the local cavitation number as parameters. The caviy extent of a propeller can be predicted more accurately by using the KD-cavitation chart at a preliminary design stage, since it is derived from the results of the cavitation observation tests in the selected ship's wake, whereas the existing cavitation charts, such as the Burrill's cavitation chart, are derived from the test results in uniform flow.

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A CYANOACETYLENE STUDY OF THE MOLECULAR DISK IN STAR FORMING REGIONS

  • Chung, H.S.;Kameya, Osamu;Morimoto, Masaki
    • Journal of The Korean Astronomical Society
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    • v.24 no.2
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    • pp.217-271
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    • 1991
  • We have observed dense core around young stellar objects, DR21, S140, Orion-KL, and L1551 using four millimeter-wave transitions of $HC_3N\;J$=4-3, J=5-4, J=10-9, and J=12-11. The spatial distribution of $HC_3N$ emission closely resembles the morphology of the previous CS observations that trace high density gas. These observations reveal the existence of $HC_3N$ dense cores around central IR source, elliptical in shape and almost perpendicular to the CO bipolar outflow axis. Small differences can be explained by that $HC_3N$ molecular line is more optically thin and is seen to be more detailed structure in the neighborhood of central IR sources. In S140 and Orion-KL, massive(${\sim}10\;M_{\odot}$), slowly rotating dense cores lie near at the central IR sources of bipolar outflows. The velocity channel maps of DR21 show that the bipolar outflow gas may have a correlation with the dense core of DR21. We analyzed intensities of the four lines to derive physical conditions in dense core from two methods, LTE and LVG. The column density of $HC_3N$, $N(HC_3N)$, between LTE and LVG calculations agree well with each other. The abundances of $HC_3N$ in each observing source have been estimated using the average values of $n(H_2)$ and $N(HC_3N)$ and assuming the size of dense core. The fractional $HC_3N$ abundances in massive dense cores of DR21, S140, and Orion-KL have a range of $(2-7){\times}10^{-10}$, while that of low mass dense core, L1551, has one order of magnitude greater value of $2{\times}10^{-9}$. This should be considered good agreement with the result by Morris et al.(1976). It may be considered that dense cores of DR21, S140, and Orion-KL may have almost same stage of chemical evolution, and their abundances have a small values relative to that of L1551. The column density $N(HC_3N)$ decreases with increasing distance from the densest part of the cloud, the central infrared source, and have the relation of $N(HC_3N){\varpropto}R^{\alpha}$, where a has a range of 0.65 to 0.89. The values of $n(H_2)$ are not varied with increasing distance from the dense core, and have almost same values. Therefore, it is considered that the dense cores in these regions probably consist of dense clumps in diffuse molecular gas medium, and $n(H_2)$ of each clump is ${\sim}10^5\;cm^{-3}$. Levels in the $T_{ex}$ increases with $n(H_2)$. It is considered that the $HC_3N$ dense cores are not completely thermalized. We examine the relationships between the luminosity of central infrared sources versus mass of the dense cores, and the luminosity of central infrared sources versus molecular hydrogen column density. Luminosities of the central IR sources show good correlation with mass and hydrogen column density of the dense core. Same has been found from CS observations. However, mass and size derived from $HC_3N$ observations are one order of magnitude smaller than those from CS. It can be interpreted that we see more central part of the cloud cores in $NC_3N$ lines than CS lines.

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Development of in-situ Sintered Ni-Al Alloy Anode for Molten Carbonate Fuel Cell (용융탄산염 연료전지용 in-situ 소결된 Ni-Al 합금 연료극 개발)

  • Chun, H.A.;Yoon, S.P.;Han, J.;Nam, S.W.;Lim, T.H.
    • Journal of the Korean Electrochemical Society
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    • v.9 no.3
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    • pp.124-131
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    • 2006
  • For commercialization of molten carbonate fuel cell (MCFC), it has some problems to be overcome such as decrease of porosity and thickness of the anode under the operating condition (at $650^{\circ}C$ and working pressure of more than 2 $kg_f/cm^2$). Recently, Ni-Al alloy anode has been proposed to replace the conventional Ni-Cr anode as an alternative material to resist a creep and inhibit the sintering. The objective of this research is to sinter the green sheet of Ni-Al alloy anode during single cell pre-treatment process, which has several advantages like cost down and simplification of manufacturing process. However, the Ni-Al alloy anode prepared with a conventional pre-treatment process showed the phase separation of Ni-Al alloy and formation of micropore(${\leqq}0.4{\mu}m$), resulting in low creep resistance and high electrolyte re-distribution. In order to prevent the Ni-Al alloy anode from phase-separating, nitrogen gas was used in the process of pre-treatment. Introducing the nitrogen, the phase separation from Ni-Al alloy into nickel and alumina was minimized and increased creep resistance. However, there was some micropore formation on the surface of Ni-Al alloy anode during the cell operation due to creation of lithium aluminate. Addition of more amount of electrolyte into a cell, especially at cathode, made the cell performance stable for 2,000 hrs. Consequently, it was possible to make the Ni-Al alloy anode with good creep resistance by the modified in-situ sintering technique.

Community Structure of Macrobenthic Fauna in the Hallyeohaesang National Park from Korea Strait, Korea (한려해상국립공원 조하대 해역 대형저서동물의 군집구조)

  • Yoon, Kon-Tak;Seo, In-Soo;Kim, Kwang-Bong;Cho, Byoung-Mi;Son, Min-Ho
    • Korean Journal of Environmental Biology
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    • v.27 no.1
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    • pp.124-133
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    • 2009
  • The study was performed to investigate the community structure of macrobenthic fauna during June 2005, in Hallyeohaesang National Park from Korea Strait. A total of 284 macrobenthic fauna were collected. The overall average macrobenthic density and biomass were 2,002 individuals m$^{-2}$ and 154.92 gWWt m$^{-2}$, respectively. Based on the Lebris (1988) index, there were 20 species accounting for approximately 47.64% of total individuals. And the highest densities were found in the polychaetes Scoletoma longifolia, Isolda pulchella, Mediomastus californiensis, Minuspio multibranchia, Tharyx sp. 1 and the bivalve Theora fragilis. On the other hand, the top twenty species made up 70.47% of the total biomass while the three most abundant, the echinoderms Schizaster lacunosus, Amphiura vadicola and the bivalve Fulvia mutica. The conventional multivariate statistics (cluster analysis and non-metric Multi-Dimensional Scaling) applied to assess spatial variation in macrobenthic assemblages. As a result of cluster analysis and nMDS ordination, this study area was divided into two different groups of stations and species. In case of station, there are two groups: one is a mud dominated station group and the other is dead shell and sand dominated group. And the 2 faunistic groups were established as follows: 1) a group of relatively higher abundances in mud dominated sediment. There were numerically dominated by the polychaetes Magelona japonica, Sternaspis scutata, Paraprionospio pinnata, Tharyx sp. 1 and the amphipods Monocorophium sinense and Eriopisella sechellensis. 2) a group of relatively higher densities dead shell and sand dominated sediment. These groups were characterized by the polychaetes I. pulchella, M. multibranchiata, the amphipods M. acherusicum, Gammaropsis japonicus and the echinoderm A. vadicola.

A Nutrition Intakes Survey of Pregnant Women in a Urban Area -Application of Convenient Method for the Study of Nutritionial Status- (일개 도시지역 임신부의 영양섭취에 관한 조사연구 -간이식 영양조사법 이용-)

  • Kim, In-Sook
    • Journal of Preventive Medicine and Public Health
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    • v.16 no.1
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    • pp.99-104
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    • 1983
  • Aiming at the total 200 pregnant women including 150 ones registered with the Health Center of Chung Ku District and 50 ones registered with the Health Center of Mapo District, we have conducted a research study of the socio-medical characteristics, maternal child health, and the status of nutritional intake which has utilized the application of convenient method for the study of nutritional status, during the period of April 20 to May 25, 1983. And we have obtained the following conclusions: 1. Regarding age distribution, the pregnant women aged from 26 to 30 were most numerous, which was 54.0%. The percentage of women who experienced the first pregnancy was 12.0% and the percentage of those who experienced the second pregnancy was 37.0%, which was the highest. Regarding the weeks of pregnancy of the pregnant women, the first trimesterr was 11.5%, the second trimester 30.0%, and the third trimester 58.6%. 2. Regarding academic achievements, the pregnant women who graduated from middle schools reached 43.5%, which was the highest percentage. Regarding economic status, the pregnant women who owned their own houses were only 21.0%. And the pregnant women whose monthly income was from 300,000 won to 400,000 won were 40%, which was the most numerous. 5. The women above 15 years old who experienced the first menstruation were 84.0%. And those who experienced abortion were totally 54.4%. and 35.5% among those women experienced artificial abortion. 4. 70.5% of the pregnant women said that their health condition was excellent, 24.5% felt subjective complaints, and 5.0% specially received medical consultation for their diseases. 5. 82.0% received prenatal care, but 60.5% regularly received prenatal care. 68.0% received the education for nutrition and only 19.5% regularly received the education for nutrition. 6. Regarding the family composition, the families consisting of two generations were 47.0%, which was the most numerous. 97.5% of the preparation for meals was conducted by housewives. They said that they did not lack time for meal preparation. 7. 94.9% of the pregnant women said that they had eaten as in ordinary times during their pregnancy. 25.5% said that there were tabooed foods. Tabooed foods are chiefly pork, chicken, milk, and eggs. 68.0% don't drink milk during pregnancy, 32.5% take the intake of vitamins, and 20.5% take iron supplement. 8. The average amounts of the intake of protein, fat, and carbohydrate of a pregnant women are 49.3gm, 29.4gm, and 205.1gm respectively, which showed the phenomenon in which the amount of the intake of nutrition increased as the weeks of pregnancy increased. The average amount of the intake of salt was 14.2gm. 9. Regarding the hemoglobin value of all pregnant women, those whose hemoglobin value was less than 11.0gm were 66.5%, those whose hemoglobin value was 11 to 12 gm were 16.5%. and those whose hemoglobin value was above 12gm were 17.0%. The pregnant women whose hemoglobin value was less than 11.0gm in the first trimester of pregnancy, in the second trimester, and in the trimester were 81.8%, 62.8%, and 64.9% respectively. This shows that the phenomenon of anemia increased as the weeks of pregnancy increased 10. Regarding physical development of a pregnant woman during prenatal period, the height and weight were $156.7cm{\pm}14.1$ and $51.1kg{\pm}58$ respectively. When the standard increase of a prenatal weigt gain is set as 100%, the women over the range of 100% were 28.0% and the women under the range of 80% were 37.0%.

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Pharmacokinetics of amoxicillin trihydrate in cultured eel Anguilla japonica by single oral and intravenous administrations (Amoxicillin trihydrate의 단독 경구투여 및 정맥투여에 따른 뱀장어, Anguilla japonica 체내 약물동태학적 특성)

  • Jeon, Eun-Ji;Seo, Jeong-Soo;Kim, Jin-Do;Jung, Sung-Hee;Kim, Myoung-Sug;Hwang, Jee-Youn;Park, Myoung-Ae;Jee, Bo-Young;Kim, Jin-Woo;Kim, Yi-Cheong
    • Journal of fish pathology
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    • v.23 no.3
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    • pp.357-367
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    • 2010
  • The pharmacokinetic properties of amoxicillin trihydrate (Amox) were studied after single oral administration and single intravenous injection to cultured eel, Anguilla japonica, respectively (average $220{\pm}10\;g$, $28{\pm}1^{\circ}C$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. The kinetic profile of absorption, distribution and elimination of Amox in plasma were analyzed fitting to a two-compartment model by WinNonlin program. In oral dosage of 40 and 80 mg/kg body weight, the peak plasma concentrations of Amox, which attained at 3~12 h post-dose, were 3.4 and $3.3\;{\mu}g/ml$, respectively. In intravenous injection with 1 mg/kg, the peak plasma concentrations of Amox, which attained at 9 h post-dose, was $7.2\;{\mu}g/ml$. The following parmeters were calculated for a single oral dosage of 40 and 80 mg/kg body weight, respectively: AUC (the area under the concentration-time curve)= 464 and $667\;{\mu}g{\cdot}h/ml$; $T_{max}$ (time for maximum concentration)= 2.1 and 3.6 h; $C_{max}$ (maximum concentration)= 3.04 and $3.4\;{\mu}g/ml$. Following intravenous injection at 1 mg/kg, this parameters were AUC= $748\;{\mu}g{\cdot}h/ml$; $C_{max}=4.2\;{\mu}g/ml$. The apparent oral bioavailability at 40 and 80 mg/kg were 1.6 and 1.1%, respectively. Despite using the trihydrate form of amoxicillin, the oral bioavailability was low in eel.

The Promotion State and Measures to Improve the Record Information Disclosure System (기록정보공개 제도 개선 추진 현황과 방안)

  • Zoh, Young-Sam
    • The Korean Journal of Archival Studies
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    • no.22
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    • pp.77-114
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    • 2009
  • The right to know is not satisfied merely by making or improving laws or systems. The right to know is a matter of culture rather than system. Nevertheless, consistent system improvement measures are required. There are many laws relating to the right to know. In particular, at the core are the Official Information Disclosure Act, the Record and Archives Management Act, and the Presidential Record Management Act. The fact that systems relating to official record management and presidential record management are related to the right to know is understood by the promotion of records and archives management reform after the year 2004, as a result of which the national archives management innovation road map was established. Reflecting the many opinions of the "Information Disclosure System Improvement Task Force" composed with participation of the government and the press after the participatory government's announcement of "Measures to Advance the Support System for News Coverage," amendments to the Information Disclosure Act have come forward with system improvement measures in connection with issues that had arisen until then. Such improvement measures have not resulted in actual improvements. This thesis proposes several system improvement measures, focusing on those that have arisen until now but have not been reflected in discussion, such as converting the concept of information non-disclosure into disclosure postponement, preparing and disclosing particular information disclosure standards, specifying personal information for non-disclosure, specifying and strictly applying any information that has not been disclosed for purposes of internal review, deleting non-disclosure items in stenographic records that do not have a reason to exist, and establishing limits and terms of non-disclosure. Of the most remarkable system improvement measures that have been made until now is our recognition that the right to know is not limited to the information disclosure system but that the "cause" of archive management should be systematic and scientific. In other words, the right to know is understood to establish not just accidential factors, such as with a whistle-blower, but the inevitable factors of systemization of production, distribution, preservation, and use of archives. Much more study should be pursued regarding disclosure of archives information. In particular, difficult issues to be resolved regarding reading records at permanent archives management institutions, such as the National Archives of Korea, or copyrights that arise in the process, require constant study from academia and relevant institutions.

Project of Improving Good Agriculture Practice and Income by Intergrated Agricultural Farming (미얀마 우수농산물 재배기술 전수사업)

  • Lee, Young-Cheul;Choi, Dong-Yong
    • Journal of Practical Agriculture & Fisheries Research
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    • v.16 no.1
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    • pp.193-206
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    • 2014
  • The objectives of the project are to increase farmers' income through GAP and to reduce the loss of agricultural produce, for which the Korean partner takes a role of transferring needed technologies to the project site. To accomplish the project plan, it is set to implement the project with six components: construction of buildings, installation of agricultural facilities, establishment of demonstration farms, dispatching experts, conducting training program in Korea and provision of equipments. The Project Management Committee and the Project Implementation Team are consisted of Korean experts and senior officials from Department of Agriculture, Myanmar that managed the project systematically to ensure the success of the project. The process of the project are; the ceremony of laying the foundation and commencing the construction of training center in April, 2012. The Ribbon Cutting Ceremony for the completion of GAP Training Center was successfully held under PMC (MOAI, GAPI/ARDC) arrangement in SAl, Naypyitaw on June 17, 2012. The Chairman of GAPI, Dr. Sang Mu Lee, Director General U Kyaw Win of DOA, officials and staff members from Korea and Myanmar, teachers and students from SAl attended the ceremony. The team carried out an inspection and fixing donors' plates on donated project machineries, agro-equipments, vehicles, computers and printer, furniture, tools and so forth. Demonstration farm for paddy rice, fruits and vegetables was laid out in April, 2012. Twenty nine Korean rice varieties and many Korean vegetable varieties were introduced into GAP Project farm to check the suitability of the varieties under Myanmar growing conditions. Paddy was cultivated three times in DAR and twice in SAl. In June 2012, vinyl houses were started to be constructed for raising seedlings and finished in December 2012. Fruit orchard for mango, longan and dragon fruit was established in June, 2012. Vegetables were grown until successful harvest and the harvested produce was used for panel testing and distribution in January 2013. Machineries for postharvest handling systems were imported in November 2012. Setting the washing line for vegetables were finished and the system as run for testing in June 2013. New water tanks, pine lines, pump house and electricity were set up in October 2013.

Identification of a Locus Associated with Resistance to Phytophthora sojae in the Soybean Elite Line 'CheonAl' (콩 우수 계통 '천알'에서 발견한 역병 저항성 유전자좌)

  • Hee Jin You;Eun Ji Kang;In Jeong Kang;Ji-Min Kim;Sung-Taeg Kang;Sungwoo Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.3
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    • pp.134-146
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    • 2023
  • Phytophthora root rot (PRR) is a major soybean disease caused by an oomycete, Phytophthora sojae. PRR can be severe in poorly drained fields or wet soils. The disease management primarily relies on resistance genes called Rps (resistance to P. sojae). This study aimed to identify resistance loci associated with resistance to P. sojae isolate 40468 in Daepung × CheonAl recombinant inbred line (RIL) population. CheonAl is resistant to the isolate, while Daepung is generally susceptible. We genotyped the parents and RIL population via high-throughput single nucleotide polymorphism genotyping and constructed a set of genetic maps. The presence or absence of resistance to P. sojae was evaluated via hypocotyl inoculation technique, and phenotypic distribution fit to a ratio of 1:1 (R:S) (χ2 = 0.57, p = 0.75), indicating single gene mediated inheritance. Single-marker association and the linkage analysis identified a highly significant genomic region of 55.9~56.4 megabase pairs on chromosome 18 that explained ~98% of phenotypic variance. Many previous studies have reported several Rps genes in this region, and also it contains nine genes that are annotated to code leucine-rich repeat or serine/threonine kinase within the approximate 500 kilobase pairs interval based on the reference genome database. CheonAl is the first domestic soybean genotype characterized for resistance against P. sojae isolate 40468. Therefore, CheonAl could be a valuable genetic source for breeding resistance to P. sojae.