• Korean Journal of Remote Sensing
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• v.35 no.6_2
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• pp.1117-1132
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• 2019

Forest covers 30% of the Earth's land area and plays an important role in global carbon flux through its ability to store much greater amounts of carbon than other terrestrial ecosystems. The Gross Primary Production (GPP) represents the productivity of forest ecosystems according to climate change and its effect on the phenology, health, and carbon cycle. In this study, we estimated the daily GPP for a forest ecosystem using remote-sensed data from Moderate Resolution Imaging Spectroradiometer (MODIS) and machine learning algorithms Support Vector Machine (SVM). MODIS products were employed to train the SVM model from 75% to 80% data of the total study period and validated using eddy covariance measurement (EC) data at the six flux tower sites. We also compare the GPP derived from EC and MODIS (MYD17). The MODIS products made use of two data sets: one for Processed MODIS that included calculated by combined products (e.g., Vapor Pressure Deficit), another one for Unprocessed MODIS that used MODIS products without any combined calculation. Statistical analyses, including Pearson correlation coefficient (R), mean squared error (MSE), and root mean square error (RMSE) were used to evaluate the outcomes of the model. In general, the SVM model trained by the Unprocessed MODIS (R = 0.77 - 0.94, p < 0.001) derived from the multi-sites outperformed those trained at a single-site (R = 0.75 - 0.95, p < 0.001). These results show better performance trained by the data including various events and suggest the possibility of using remote-sensed data without complex processes to estimate GPP such as non-stationary ecological processes.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.65-71
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• 2013

This research was conducted to evaluate the influence of $NO_3{^-}:NH_4{^+}$ ratios in fertilizer solution on the vegetative growth and fruit yield of hot pepper (Capsicum annuum L.) through pot cultivation. The Hoaglad's solution was modified to contain various $NO_3{^-}:NH_4{^+}$ ratios such as 100:0 (A), 73:37 (B), 50:50 (C), 27:73 (D), 0:100 (E), and no nitrogen (F). Plants were transplanted into root substrates and the modified solutions were applied as plant needed in plastic house. There were no statistical significances among the treatments from A through D in the fresh and dry weights, and number of leaves 31 days after transplanting, but elevation of $NH_4{^+}$ ratios in the solution decreased the fresh fruit weight 62 days after transplanting with statistical differences. In the results of inorganic element analysis based on the dry weight of fully expanded mature leaves, N and P contents as well as micro cations such as Fe, Mn, Zn, and Cu increased as $NH_4{^+}$ ratios were elevated 62 days after transplanting. However, those of macro cations such as K, Ca, and Mg resulted in decreasing tendency. The elevation of $NH_4{^+}$ ratios in fertilizer solution resulted in the increase of EC and total N concentrations ($NO_3{^-}+NH_4{^+}$), but this decreased the pH as well as Ca and Mg concentrations in soil solution 62 days after transplanting. The K concentration in soil solution was the highest in the treatments of C and followed by D, B, E, and A. The above results indicate that the proper $NO_3{^-}:NH_4{^+}$ ratio in the nutrient solution is 73:27 (B) or 100:0 (A) and the B solution is proper for the vegetative growth and that of A is proper for reproductive growth stage.

• (The)Study of the Eastern Classic
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• no.37
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• pp.33-61
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• 2009

In the late Koryo period, until 14th century, there had been at least two groups of Manchurians who were conferred citizenships; one group was living as an original inhabitant in the coastal area of north­eastern part of Korean peninsular, long time ago, and they were over one thousand households. The other was coming down from inland, eastern part of Yoha River, to the area of Tuman River to settle down and they were at least around one hundred and sixty households, including such tribes as Al-tha-ry, Ol-lyang-hap, Ol-jok-hap and others. They were treated courteously, from the early days of Choson dynasty, with governmental policies in an economic, political, and social ways. They were given, for instance, a house, a land, household furniture, and clothes. They were allowed to get marry with a native Korean to settle down. They were educated how to cultivate their lands. It was also possible for them to be given an official position politically or allowed to take a National Civil Official Examination. The fact they could take such an Examination, in particular, means they were treated fairly and equally, because they also had a privilege to improve their social positions through the formal system as much as common people. Two typical families were scrutinized, in this paper, family Chong-hae Lee and family Chon-ju Ju. All of them were successful to settle down with different backgrounds each other. The former were from a headman, Lee Jee-ran, who controlled his tribe, over five hundred households. He was given three titles of a meritorious retainer at the founding of Chosun dynasty, at the retrieval of armies, and an enshrined retainer. His son, Lee Wha-yong, was also given a vassal of merit who kept a close tie successfully with the king's family through a marriage. Upon the foundation of their ancestors, their grandsons, family Lee Hyo-yang and family Lee Hyo-gang, each, had taken solid root as an aristocratic Yang-ban class. The former became a high officer family, generation by generation, while the latter changed into a civil official family through Civil Official Examinations. They lived mainly around Seoul, Kyong-gi Province and some lived in their original places, Ham-kyong Province. Chu-man, the first ancestor, was given a meritorious retainer at the founding of the dynasty and Chu-in was also given a high officer position from the government. They kept living at the original place, Ham-heung, Ham-kyong Province, and then became an outstanding local family there. They began to pass the Civil Official Examinations. After 17th century on the passers were 17 in Civil Official Examinations and 40 were passed in lower civil examinations. The positions in government they attained usually were remonstrance which position was prohibited particularly to North­Western people at that time. The Chosun dynasty was open to Machurians widely through the system of envoy, convoy, and naturalization. It was intended to build up an enclosure policy through a friendly diplomatic relation with them against any possible invasion from outside. This is one reason why they were supported fully that much in a various way.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.91-103
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• 2012

The aim of this study was to develop a rapid and cheap bioassay of four lignans (schisandrin, schisandrin C, the gomisin A and gomisin N) isolated from Schizandra chinensis Baill on seed germination and seedling growth of the radish. Its structure was determined by analysis of MS and NMR spectroscopic data. Radish seeds immersed for 1 hr in the solutions of $10^{-5}M$, $10^{-6}M$ and $10^{-7}M$ of schisandrin, schisandrin C, gomisin A, and gomisin N, seed germination was observed with in 60 hr after all of the treatments. Also, the seeds were germinated faster compared to untreated controls. At early germination stage, 48 hr after the treatment of the lignans, the suppression of germination was observed from all treatments; the suppression due to schisandrin and gomisin A was the highest at the concentration of $10^{-6}M$. The level of suppression increased as the concentration increased in the treatment of schisandrin C and gomisin N. Percent germination of seed after 184 hr was increased 90% at all treatments. For the effects of lignan treatment on seedling growth in radish, the growth of hypocotyl was promoted by gomisin A and gomisin N at all concentrations. Root elongation was significantly promoted by schisandrin and gomisin N at $10^{-5}M$ and $10^{-6}M$, respectively. Fresh and dry weights of the seedlings were high at a low concentration of $10^{-7}M$, but significantly reduced by schisandrin C at a high concentration of $10^{-5}M$. The results of the germination activity and seedling growth of the lignans from S. chinensis suggest their potential use as natural growth regulators.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.1-8
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• 1976

1. Under an asumption that Ficks diffusion equation could be applicable in soil systems, the diffusivities of NaCl in several flooded soil systems were measured to range from $0.4{\times}10^{-5}cm^2sec^{-1}$ to $0.83{\times}10^{-5}cm^2sec^{-1}$ 2. It was discussed that, when a polder soil with a uniform initial salt content through the profile is desalinated only by diffusion to flooding water, the salt content in profile is a function of soil depth, diffusion time, and diffusivity as following $$C=C^{\circ}erf\frac{x}{\sqrt[2]{Dt}}$$ 3. On the basis of Kirkham, et al's integration of complementary erra function, the speed of desalting was discussed to be inversely proportional to the square root of time as following $$dq/dt=C^{\circ}{\sqrt{D/{\pi}t}}$$ 4. It was estimated enough to exchange the flooding water once or twice, even when desalination of polder soil is carried out only by diffusion, if the desalination begins in June, the used flooding water is fresh water, and flooding depth is 10cm. 5. Desalination of polder soil by diffusion requires 2 month for good standing of planted rice.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.77-94
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• 2021

The purpose of this study was to investigate the three-dimensional characteristics of mesiodens using Cone-beam Computed Tomography(CBCT) and analyze the factors affecting complications and anesthetic methods of extraction. This study evaluated 602 mesiodens of 452 patients who underwent extraction of mesiodens at the department of Pediatric Dentistry in Seoul National University Dental Hospital between 2017 and 2019. The ratio of mesiodens patients over total patient per year was gradually increased over the past 20 years. Mesiodens with labio-palatally horizontal direction while root directing labial were the most common among the mesiodens with horizontal direction. Mesiodens were the most common at the cervical side of the adjacent teeth(37.0%) and mesiodens located in the near-palatal side were observed about 3.83 times higher than the far-palatal side. Most of the mesiodens(82.1%) were in contact with adjacent permanent teeth on all three sides of the CBCT and 46.2% of mesiodens had curved roots. The patient's age, vertical position, presence of complications, and proximity showed a significant difference in the selection of general anesthesia among anesthetic methods. The direction and vertical position of mesiodens had a significant effect on complications. These results provide a better understanding of mesiodens for establishing an accurate diagnosis and treatment plan.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.64-80
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• 2018

In Korea, citizens can only know general information about crime. Thus it is difficult to know how much they are exposed to crime. If the police can predict the crime risky area, it will be possible to cope with the crime efficiently even though insufficient police and enforcement resources. However, there is no prediction system in Korea and the related researches are very much poor. From these backgrounds, the final goal of this study is to develop an automated crime prediction system. However, for the first step, we build a big data set which consists of local real crime information and urban physical or non-physical data. Then, we developed a crime prediction model through machine learning method. Finally, we assumed several possible scenarios and calculated the probability of crime and visualized the results in a map so as to increase the people's understanding. Among the factors affecting the crime occurrence revealed in previous and case studies, data was processed in the form of a big data for machine learning: real crime information, weather information (temperature, rainfall, wind speed, humidity, sunshine, insolation, snowfall, cloud cover) and local information (average building coverage, average floor area ratio, average building height, number of buildings, average appraised land value, average area of residential building, average number of ground floor). Among the supervised machine learning algorithms, the decision tree model, the random forest model, and the SVM model, which are known to be powerful and accurate in various fields were utilized to construct crime prevention model. As a result, decision tree model with the lowest RMSE was selected as an optimal prediction model. Based on this model, several scenarios were set for theft and violence cases which are the most frequent in the case city J, and the probability of crime was estimated by $250{\times}250m$ grid. As a result, we could find that the high crime risky area is occurring in three patterns in case city J. The probability of crime was divided into three classes and visualized in map by $250{\times}250m$ grid. Finally, we could develop a crime prediction model using machine learning algorithm and visualized the crime risky areas in a map which can recalculate the model and visualize the result simultaneously as time and urban conditions change.

• The Korean Journal of Archival Studies
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• no.38
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• pp.75-124
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• 2013

This study aims, by paying attention to the special values of records of Constitutional Court, to discuss the characteristics of them and figuring out their present state, and to suggest some measures for improvement in the records management. First of all, I defined the concept of the records of Constitutional Court and its scope, and made an effort to comprehend their types and distinct features, and on the basis of which I tried to grasp the characteristics of the records. Put simply, the records of Constitutional Court are essential records indispensible to the application of Constitutional Court's documentation strategy of them, and they are valuable particularly at the level of the taking-root of democracy and the guarantee of human rights in a country. Owing to their characteristics of handling nationally important events, also, the context of the records is far-reaching to the records of other constitutional institutions and administrations, etc. In the second place, I analyzed Records Management Present State. At a division stage, I grasped the present state of creation, registration, and classification system of records. At an archives repository stage, I made efforts to figure out specifically the perseveration of records and the present of state of using them. On the basis of such figuring-outs of the present situation of records of Constitutional Court, I pointed at problems in how to manage them and suggested some measures to improve it in accordance with the problems, by dividing its process into four, Infrastructure, Process, Opening to the public and Application. In the infrastructure process, after revealing problems in its system, facilities, and human power, I presented some ways to improve it. In terms of its process, by focusing on classification and appraisal, I pointed out problems in them and suggested alternatives. In classification, I suggested to change the classification structure of trial records; in appraisal, I insisted on reconsidering the method of appropriating the retention periods of administration records, for it is not correspondent with reality in which, even in an file of a event, there are several different retention periods so it is likely for the context of the event worryingly to be segmented. In opening to the public and application, I pointed at problems in information disclosure at first, and made a suggestion of the establishment of a wide information disclosure law applicable to all sort of records. In application, I contended the expansion of the possibility of application of records and the scope of them through cooperation with other related-institutions.

• Journal of Korea Water Resources Association
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• v.53 no.12
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• pp.1081-1095
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• 2020

This study is to evaluate stream flow and water quality changes of Yeongsan river basin (3,371.4 km2) by inter-basin water transfer (IBWT) from Juam dam of Seomjin river basin using SWAT (Soil and Water Assessment Tool). The SWAT was established using inlet function for IBWT between donor and receiving basins. The SWAT was calibrated and validated with 14 years (2005 ~ 2018) data of 1 stream (MR) and 2 multi-functional weir (SCW, JSW) water level gauging stations, and 3 water quality stations (GJ2, NJ, and HP) including data of IBWT and effluent from wastewater treatment plants of Yeongsan river basin. For streamflow and weir inflows (MR, SCW, and JSW), the coefficient of determination (R2), Nash-Sutcliffe efficiency (NSE), root mean square error (RMSE), and percent bias (PBIAS) were 0.69 ~ 0.81, 0.61 ~ 0.70, 1.34 ~ 2.60 mm/day, and -8.3% ~ +7.6% respectively. In case of water quality, the R2 of SS, T-N, and T-P were 0.69 ~ 0.81, 0.61 ~ 0.70, and 0.54 ~ 0.63 respectively. The Yeongsan river basin average streamflow was 12.0 m3/sec and the average SS, T-N, and T-P were 110.5 mg/L, 4.4 mg/L, 0.18 mg/L respectively. Under the 130% scenario of IBWT amount, the streamflow, SS increased to 12.94 m3/sec (+7.8%), 111.26 mg/L (+0.7%) and the T-N, T-P decreased to 4.17 mg/L (-5.2%), 0.165 mg/L (-8.3%) respectively. Under the 70% scenario of IBWT amount, the streamflow, SS decreased to 11.07 m3/sec (-7.8%), 109.74 mg/L (-0.7%) and the T-N, T-P increased to 4.68 mg/L (+6.4%), 0.199 mg/L (+10.6%) respectively.