• The Korean Journal of Quaternary Research
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• v.24 no.2
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• pp.35-48
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• 2010

The purpose of this study is to investigate paleoenvironmental conditions of the shallow sea around Jeju Island during the Late Holocene using geochemical contents of the bivalve (Glycymeris albolineata) collected from the Sangmori Shell Mound. The bivalve shell used shows the archaeological age of 2,300 yr BP. Stable carbon and oxygen isotope compositions show that growth rates decreased with aging. Coeval trends of both isotope compositions can be observed: heavier values during winters and lighter values summers except for their young and old growth stages. The seasonality of bivalve shell appear to reflect seasonal variations of paleotemperature as well as paleosalinity. Especially China Coastal Water with low salinity was transported into the southern Jeju Strait from Changjiang River during summer periods. Heavier carbon isotope values during winter indicate higher productivity, and this is supported by high density of phytoplanktons and higher chlorophyll contents during winter time. For accurate interpretation, monitoring of present-day conditions of shallow marine water as well as additional geochemical analysis of the same Recent bivalve may be necessary.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.233-246
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• 2009

The partitioning of evapotranspiration (ET) into evaporation (E) and transpiration (T) is critical in understanding the water cycle and the couplings between the cycles of energy, water, and carbon. In forests, the total ET measured above the canopy consists of T from both overstory and understory vegetation, and E from soil and the intercepted precipitation. To quantify their relative contributions, we have measured ET from the floors of deciduous and coniferous forests in Gwangneung using eddy covariance technique from 1 June 2008 to 31 May 2009. Due to smaller eddies that contribute to turbulent transfer near the ground, we performed a spectrum analysis and found that the errors associated with sensor separation were <10%. The annual sum of the understory ET was 59 mm (16% of total ET) in the deciduous forest and 43 mm (~7%) in the coniferous forest. Overall, the understory ET was not negligible except during the summer season when the plant area index was near its maximum. In both forest canopies, the decoupling factor ($\Omega$) was about ~0.15, indicating that the understory ET was controlled mainly by vapor pressure deficit and soil moisture content. The differences in the understory ET between the two forest canopies were due to different environmental conditions within the canopies, particularly the contrasting air humidity and soil water content. The non-negligible understory ET in the Gwangneung forests suggests that the dual source or multi-level models are required for the interpretation and modeling of surface exchange of mass and energy in these forests.

• Korean Security Journal
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• no.42
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• pp.229-249
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• 2015

As the post-cold war era and globalization go on, national security problems which were not traditional national security problems such as terrorism, crime, environmental disasters, economic crises, cyber-terrorism, diseases, and energy problems threat humanity and nations and demands changes. Also, with the change, the concept of "big government" has emerged as the role of nation expanded. The modern society sees every country change from small government to big government in order to realize the establishment of welfare state. A comprehensive interpretation of security is needed in order to comprehensive protection of citizens beyond outside invasion such as crime, new disaster, terrorism. In Korea, incidents such as Cheonan-Ham, Yeonpeyong-Do, foot-and-mouth disease, Ddos terrorism, pirates hostages, mad cow disease, AI are happening and the humanitarian support for North Korea and the summit of South and North Korea are at a standstill. Also, National emergency management system, comprehensive emergency management center, countrol tower, national security system, cooperation with citizens, establishment of legal and institutional system are needed. The importance of this research is on the reestablishment of new national security and emergency management system according to the comparison between the national security and counter-terrorism system of Korea and that of the United States which is a leading country in this field. Also, the establishment of national emergency management act is needed as a statute for effective function as currently various laws and administrative organizations are dispersed.

• Journal of Soil and Groundwater Environment
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• v.7 no.1
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• pp.63-77
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• 2002

Salinization is an important environmental problem encountered in coastal aquifers. In order to evaluate the salinization problem in the western coastal area of Korea, we have performed a regional hydrochemical study on shallow well groundwaters (N=229) collected within 10 km away from the coastline. The concentrations of analyzed solutes are very wide in range, suggesting that the hydrochemistry is controlled by several processes such as water-rock interaction, seawater mixing, and anthropogenic contamination. Based on the graphical interpretation of cumulative frequency curves for some hydrochemical parameters (esp., $Cl^{-}$ and ${NO_3}^-$), the collected water samples were grouped into two major populations (1) a background population whose chemistry is predominantly affected by water-rock interaction, and (2) an anomalous population which records the potential influences by either seawater mixing or anthropogenic pollution. The threshold values obtained are 34.7 mg/l for $Cl^{-}$ and 37.2 mg/l for ${NO_3}^-$, Using these two constituents, groundwaters were further grouped into four water types as follows (the numbers in parenthesis indicate the percentage of each type water) : (1) type 1 waters (38%) that are relatively poor in $Cl^{-}$ and ${NO_3}^-$, which may represent their relatively little contamination due to seawater mixing and anthropogenic pollution; (2) type 2 waters (21%) which are enriched in $Cl^{-}$, Indicating the considerable influence by seawater mixing; (3) ${NO_3}^-$-rich, type 3 waters (11%) which record significant anthropogenic pollution; and (4) type 4 waters (30%) enriched in both $Cl^{-}$ and ${NO_3}^-$, reflecting the effects of both seawater mixing and anthropogenic contamination. The results of the water type classification correspond well with the grouping on a Piper's diagram. On a Br x $10^4$versus Cl molar ratio diagram, most of type 2 waters are also plotted along or near the seawater mixing line. The discriminant analysis of hydrochemical data also shows that the classification of waters into four types are so realistic to adequately reflect the major process(es) proposed for the hydrochemical evolution of each water type. As a tool for evaluating the degree of seawater mixing, we propose a parameter called 'Seawater Mixing Index (S.M.I.)’ which is based on the concentrations of Na, Mg, Cl, and $SO_4$. All the type 1 and 3 waters have the S.M.I. values smaller than one, while type 2 and type 4 waters mostly have the values greater than 1. In the western coastal area of Korea, more than 21% of shallow groundwaters appear to be more or less affected by salinization process.

• Parasites, Hosts and Diseases
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• v.58 no.2
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• pp.147-152
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• 2020

Malaria is a potent burden on public healthcare worldwide due to requiring rapid diagnosis and treatment. Nowadays, prompt diagnosis with rapid diagnostic tests (RDTs) has been widely accepted as an effective diagnostic technique in malaria-endemic countries, primarily due to their easy operation, fast output, and straightforward interpretation. The global availability and use of RDTs have gradually grown over recent decades as field-applicable diagnostic tests for the reliable confirmation of malaria infection and proper case management. This study was conducted to evaluate diagnostic performance of 3 commercially available malaria RDT kits : BIOCREDIT^TM Malaria Ag Pf(pLDH), Malaria Ag Pf(pLDH/pHRPII), and Malaria Ag Pf/Pv(pLDH/pLDH) (where pLDH and pHRPII stand for plasmodium lactate dehydrogenase and histidine-rich protein 2, respectively) for the specific detection of Plasmodium falciparum. A total of 1,129 blood samples including 95 blood samples, confirmed as vivax malaria infection by microscopic examinations and a nested-PCR method, were tested for falciparum malaria infection. The overall sensitivity and specificity of Malaria Ag Pf(pLDH/pHRPII), Malaria Ag Pf/Pv(pLDH/pLDH), and Pf(pLDH) for P. falciparum were 99.0% and 100%, 95.8% and 100%, and 100% and 100%, respectively. It is proposed that the 3 RDT kits perform reliable level of diagnostic accuracy of detection for P. falciparum parasites.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.2
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• pp.45-56
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• 2010

This study is dealing with Deoksugung around the founding of the Daehan Empire Era. It will looks closely into how locational contexts and sense of place have been changed according to the subject's view point and the interpretation of text community until Deoksugung is changed into citizen-oriented public place vested with the meaning of public park. In conclusion, Deoksugung was a place for suffering and sorrows, but also it was a place for ceaseless attempt to pursue of the recovery of past without loosing hope. As in the case of uprising war like Japanese invasion of Korea (Imjin Yeran) or Cheong Japan War, Deoksugung was an importantly historical place where autocrat temporarily stayed to stand up for the war and moreover, it was an imperial palace where the ambivalent sensibility between suffering and hope are intermingled in the very first Korean Empire in history. Unlike Kyeongbokgung and Changdeokgung, the current Deoksugung has changed its boundary from time to time since Japanese invasion of Korea up to the present. Deoksugung has evolved the present situation as endlessly changing its boundary by interacting with the neighbor of Kyungungung. The more complicated sense of place is coexisted in the features of the Deoksugung. Therefore, current hot topics concerning restoration project of Deoksugung is much more difficult than of other palaces. This issues should be carefully dealt with beyond the political interests.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.4
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• pp.89-97
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• 2016

This study looked at the sacrifice space building in the Changbai Mountain area to a specific era in terms of the cultural landscape. The scared of Changbai Mountain how changes in history came despite the regime and national change, interpretation of the reason was the scared maintained. The results of this study are as follows. First, Replacement of the regime in the Republic of China in the Qing period, ethnic diversity, underwent a cultural acceptance. So Changbai Mountain nature of sacrifice, the divine subject has formed the changes. Second, the Qing Royal sacrifice space Wangji Temple(望祭殿) have formed a unique cultural space and the sacrifice of authoritative content with only space. The Republic of China period, a new folk beliefs were born between the defense in the face of the Han Chinese migration and settlement process. Build Sacrifice space of Rulai Temple(如來寺) and Shanshenlaobatou Temple(山神老把頭廟). Third, the spatial relationship between the priest and the Changbai Mountain area Wangji Temple(望祭殿) is the power of space as vertical space. Rulai Temple(如來寺), Shanshenlaobatou Temple(山神老把頭廟) is located in the Changbai Mountain and horizontal space was obedient to the space. Fourth, the sacrifice ritual Wangji Temple(望祭殿) of the Qing Dynasty is the only ritual sacrifice of satisfaction. It is cut off depending on the abolition of imperial power. Currently, public ritual sacrifice is commonplace rituals and sacrifices of the Qing Dynasty is only formally underway. In conclusion, as it has been maintained for the sanctity historically Changbai Mountain. Changbai Mountain sacrifice space was changing through the acceptance of the replacement of the regime and culture of ethnic offerings from a single culture of the Qing Dynasty. Currently, to form a sacrifice space and culture overlap through a mutually acceptable.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.29-42
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• 2017

Jeongeuihyanggyo(旌義鄕校) is a kind of traditional, Confucian cultural landscapes that is located in Jeju special self-governing province. Its historical background illustrates that the first erection was started at Goseong-li of Seongsan-eup(城山邑 古城里) at Taejong(太宗) of 16 years(1417) and it moved to the west gate of Hyunseong(縣城) at Heojong(憲宗) of 15 years,(1849) Joseon. The aim at this study is to reveal characters of these Confucian Spatial Composition and Order, which are valuable resources that can be created into the cultural contents. The results demonstrate the characters of the Confucian cultural landscape as followings; the changing process of new building and its relocation, the utilization of antique maps in location interpretation of Jeongeuihyanggyo, Confucian symbolic elements of it, the spatial compositions and layouts of its buildings, physical structures, main buildings and their characters, locational points of topographic profile, changes of axial line at Daeseongjeon(大成殿), the D/H ratio of its courts. This study can show that Jeongeuihyanggyo is a case for realizing the Confucian reformation to enhance Seongeup Hyun's education standard considering the locality of the site which is an isolated island like Jejudo(濟州島). The author can see that the example of Confucian space is applied to various layout techniques, both horizontally and vertically, in a limited space condition of being in the castle. Therefore, it is necessary to revive this point so that it can utilize unique Confucian cultural landscape possessed only by Jeongeuihyanggyo.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.413-413
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• 2019

하천과 호수에서 남조류의 이상 과잉증식 문제(이하 녹조문제)는 담수생태계의 생물다양성을 감소시키며, 음용수의 이취미 원인물질을 발생시켜 물 이용에 장해가 된다. 또한 독소를 생산하는 유해남조류가 대량 증식할 경우에는 가축이나 인간의 건강에 치명적 해를 끼치기도 한다. 그 동안 국내에서 녹조문제는 댐 저수지와 하구호와 같은 정체수역에서 간헐적으로 문제를 일으켰으나, 4대강사업(2010-2011)으로 16개의 보가 설치된 이후 낙동강, 금강, 영산강 등 대하천에서도 광범위하게 발생되고 있어 중요한 사회적 환경적 이슈로 대두되었다. 한편, 대하천에 설치된 보 구간에서 빈번히 발생하는 녹조현상의 원인에 대해서는 전 지구적 기온상승에 따른 기후변화의 영향이라는 주장과 유역으로부터 영양염류의 과도한 유입, 가뭄에 따른 유량감소, 보 설치에 따른 체류시간 증가 등 다양한 의견이 제시되고 있으나, 대상 유역과 수체의 특성에 따라 녹조 발생의 원인이 상이하거나 또는 다양한 요인이 복합적으로 작용하기 때문에 보편적 해석(universal interpretation)이 어려운 것이 현실이다. 따라서 각 수계별, 보별 녹조현상에 대한 정확한 원인분석과 효과적인 대책 마련을 위해서는 집중된 실험자료와 데이터마이닝 기법에 근거로 한 보다 과학적이고 객관적인 접근이 이루어져야 한다. 본 연구에서는 2012년 보 설치 이후 남조류에 의한 녹조현상이 빈번히 발생하고 있는 낙동강 4개보(강정고령보, 달성보, 합천창녕보, 창녕함안보)를 대상으로 집중적인 현장조사와 실험분석을 수행하고, 수집된 기상, 수문, 수질, 조류 자료에 대해 통계분석과 다양한 데이터모델링 기법을 적용하여 보별 남조류 우점 환경조건과 이를 제어하기 위한 주요 조절변수를 규명하는데 있다. 연구대상 보 별 수질과 식물플랑크톤의 정성 및 정량 실험은 2017년 5월부터 2018년 11월까지 2년에 걸쳐 실시하였으며, 남조류 세포수 밀도와 환경요인과의 상관성 분석을 실시하고, 단계적 다중회귀모델(Step-wise Multiple Linear Regressions, SMLR), 랜덤포레스트(Random Forests, RF) 모델과 재귀적 변수 제거 기법(Recursive Feature Elimination using Random Forest, RFE-RF)을 이용한 변수중요도 평가, 의사결정나무(Decision Tree, DT), 주성분분석(Principal Component Analysis, PCA) 기법 등 다양한 모수적 및 비모수적 데이터마이닝 결과를 바탕으로 각 보별 남 조류 우점 환경요인을 종합적으로 해석하였다.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.2
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• pp.121-131
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• 2021

Magnesium (Mg) present in carbonate minerals as impurities has been used as a geochemical proxy to infer the environmental conditions where the minerals precipitated. The reliability of Mg geochemical proxies requires fundamental understanding of Mg incorporation into minerals based on accurate speciation of Mg ²⁺ in the crystal structure, which is determined mainly by application of X-ray absorption spectroscopy (XAS). However, high uncertainties are involved in interpreting the XAS spectra of minerals containing trace amount of Mg ²⁺. Because density function theory (DFT) can predict an XAS spectrum for a crystal structure, DFT calculations can reduce the uncertainties in the interpretation of the XAS spectrum. In this study, we calculated ab initio Mg K-edge absorption spectra of Mg silicates and (hydr)oxides based on DFT and analyzed the correlation between the calculated spectra and Mg structural parameters. Our ab initio Mg K-edge absorption spectra well reproduced the key features of the experimental spectra. The absorption-edge positions of the calculated spectra showed the weak positive correlation with the average Mg-O bond distance or Mg effective coordination number. The current study shows that DFT-based core-level spectroscopy method is a powerful tool in providing standard Mg K-edge spectra of diverse Mg minerals and determining the Mg chemical species within carbonate minerals.