• Journal of the Mineralogical Society of Korea
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• 제4권1호
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• pp.1-10
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• 1991

Tosudite from the Sungsan mine, Korea is an alteration product of rhyolitic tuff in the cretaceous Hwangsan Formation. It is associated with illite, dickite, nacrite or quartz and also found in the cavities of black claystone. X-ray diffraction and chemical analyses show that the Sungsan tosudite is a lithium-bearing aluminous 1:1 regularly interstratified mineral of di, dioctahedral chlorite and smectite. Its structural formula is $(K_{0.73}Na_{0.02}Ca_{0.07})(Si1_{13.23}Al_{2.77})(Li_{0.52}Mg_{0.08}Mn_{0.01)Fe^{3+}_{0.07}Al_{12.33})O_{40}(OH)_{20}$ and it suggests that Sungsan tosudite consists of regularly interstratified Li-donbassite and beidellite. DTA and TG curves as well as IR absorption data also support such a result. Temperature of formation of tosudite is inferred to be between $110{\circ}$ and $270{\circ}C$.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2016년도 학술발표회
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• pp.431-431
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• 2016

J 호소는 1942년도에 충청남도 아산시 선장면에 설치된 농업용 저수지로서, 현재 COD, TN, TP 모두 등급외의 수질상태를 보이고 있다. J 호소 상류 유역은 축산농가가 다수 위치하고 있으며, 설치된 지 70년이 지난 노후화된 저수지로 고농도의 오염물질 유입뿐만 아니라 호소 바닥의 오염 퇴적물에 의한 내부 부하가 중요한 수질오염원이 되고 있다. 호소의 수질은 현재 COD 10.6~16.5 mg/L, Chl-a $75mg/m^3$ 이상으로 수질오염도가 매우 높으며, 특히 늦봄에서 초가을까지 외기온도 상승 및 저수율 저하와 함께 부영양화 증가, 녹조 대발생 등으로 호 내 물고기 대량 폐사 및 악취발생 등으로 민원이 다수 발생하고 있다. 이러한 현상의 직접적인 원인은 수중의 DO 농도 결핍이며, 따라서 수중의 DO 농도를 일정수준 이상으로 유지시켜 주는 것은 호소 수질관리를 위해 매우 필요하다고 판단된다. 본 연구에서는 공기 중의 산소를 호소 수체에 포기시켜 주는 마이크로버블 발생장치를 J 저수지에 설치하여 수체의 DO 농도 변화 등을 분석하였고, 본 연구결과는 농업용 호소의 수질개선을 위한 기술개발 및 계획수립의 기초자료로 활용하고자 하였다. 마이크로버블 포기장치는 수심이 약 4m 되는 저수지 제방 근처에 100m 간격으로 총 3지점에 설치하였다. 버블 발생기는 기액 2상류 선회형 마이크로 버블 발생장치로 3지점에 각 1set(1set에 3기로 구성)씩 구성하여 저수지 바닥 층에서 상부로 1m 떨어진 지점에 고정식으로 설치하였다. 총 공기흡입량은 380 LPM이며, 사용동력은 12.2kW를 사용하였다. 마이크로 버블 포기장치 설치 후 호 내 DO 농도 변화를 평가하기 위하여 호소 전체에 18개 지점을 선정하여 수심 50cm 간격으로 DO 농도를 측정하였다. 가동 전에는 DO 평균농도가 표층에서는 약 7.7mg/L로 나타났고, 수심에 따라 거의 수직적으로 감소하여 바닥층에서는 약 0.2mg/L로 거의 무산소 상태를 보이고 있었다. 마이크로 버블 가동 2주 후에는 수심 3m까지의 모든 수층에서 DO 농도가 약 6.0mg/L 이상을 보였고, 바닥층에서는 DO 약 3.4mg/의 농도를 나타내었다. 가동 3주 후에도 2주 후와 비슷한 수치를 보이고 있었으나 가동 4주가 지나면서부터는 호소 바닥층(수심 3.5m)에서도 DO 농도가 7.0mg/L 이상의 높은 농도를 유지하는 것으로 조사되었다. 호소 저층에서 호기성 상태의 지속적 유지는 퇴적 오염물질이 수층으로 용출되는 것을 예방할 수 있으므로 마이크로버블을 잘 활용하면 호소의 악취제거 및 수질개선에 많은 도움이 될 것으로 판단된다.

• Korean Journal of Soil Science and Fertilizer
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• 제32권4호
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• pp.327-332
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• 1999

Manganese (Mn) oxides in soils have been a research subject since they react with nutrients and contaminants and Mn itself is an essential element for plant growth. Birnessite was synthesized in the presence of iron (Fe) in the precipitating solution. Influence of Fe, one of common elements in soils, on crytallinity, morphology, and chemical reactivity of birnessite was examined using X-ray diffraction (XRD), electron microscope, canon exchange capacity (CEC), and chromium (Cr) oxidation capacity. With increasing Fe concentration in the precipitating solution, crystallinity and crystal size decreased. Hexagonal plates of the birnessites formed at low Fe concentration were dominant and replaced more and more by aggregate of small particles with increasing the Fe concentration. There is no significant change in CEC with changing the Fe concentration. Chromium oxidation capacity of the birnessite increased with increasing the Fe concentration. Iron in the precipitating solution poisoned crystal growth by adsorption on the surface and increased nucleation. Since Fe is a common constituent under pedogenic environment and Fe and Mn oxides often coexist in Mn oxide nodules, the birnessite with small particle, low crystallinity, and high chemical reactivity is the form which is more likely to be formed in soils. The high CEC ($140cmol_ckg^{-1}$) and oxidation capacity of birnessite indicate that birnessite can be used in environment and agriculture.

• Journal of Aerospace System Engineering
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• 제15권5호
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• pp.33-42
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• 2021

Modern aircraft fighters improve the maneuverability and performance with the RSS (Relaxed Static Stability) concept and therefore these aircrafts are susceptible to abrupt pitch-up in the transonic and moderate Angle-of-Attack (AoA) flight region where the shock wave is formed and the mean aerodynamic center is moved forward during deceleration. Also, the modeling of the aircraft flying in this flight region is very difficult due to complex flow filed and unpredictable dynamic characteristics and the model-based control design technique does not fully cover this problem. In this paper, we analyzed the performance of the TPMC (Transonic Pitching Moment Compensation) control based on the model-based IDI (Incremental Dynamic Inversion) and the Hybrid IDI based on the model and sensor based IDI during the SDT (Slow Down Turn) in transonic region. As the result, the Hybrid IDI had quicker response and the same maximum g suppression performance and provided the predictable flying qualities compared to the TPMC control. The Hybrid IDI improved the performance of the Over-G protection controller in the transonic and moderate AoA region

• The Korean Society of Law and Medicine
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• 제21권2호
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• pp.3-33
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• 2020

Until recently the German and the South Korean medical associations reacted cautiously to the introduction of telemedicine between doctor and patient which is exclusively on the platform conducted. But the General Assembly of German Physicians voted to lift the ban on remote treatment with the amendment to Section 7 (4) MBO-Ä(Medical Association's Professional Code of Conduct) in 2018 and the situation has been fundamentally changed in Germany. From then until now 16 of 17 rural medical associations have changed their professional code to allow telemedicine. In addition the legislature started to prepare the basis for the introduction of the electronic health card (eGK) and the telematics infrastructure. So far, various laws such as Medicinal Products Act, Drug Advertisement Act and Social Code have been changed to support legalization of telemedicine and digitalization of health care. Unlike in Germany, the social circumstances such as excessive centralization of the big hospitals in Seoul and the resulting concern of small medical practices for profitability are the main obstacles to the introduction of telemedicine. However the German approach how to legalise the telemedicine and to prepare for legal and technical infrastructure is also interesting in South Korea. The discussions for and against the changes in the law and the telematics infrastructure attempted by the German government for several years indicate that not only lifting the ban on remote treatment, but also harmonization of all the related legal system could guarantee successful implementation of telemedicine.

• Clean Technology
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• 제25권1호
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• pp.74-80
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• 2019

Thermochemical treatment of sewage sludge is an energy-intensive process due to its high moisture content. To save the energy consumed during the process, the hydrothermal carbonization process for sewage sludge can be used to convert sewage sludge into clean solid fuel without pre-drying. This study is aimed to investigate co-firing characteristics of the hydrothermally carbonated sewage sludge (HCS) to a pulverized coal combustion system. The purpose of the measurement is to measure the pollutants produced during co-firing and combustion efficiency. The combustion system used in this study is a furnace with a down-firing swirl burner of a $80kW_{th}$ thermal input. Two sub-bituminous coals were used as a main fuel, and co-firing ratio of the sewage sludge was varied from 0% to 10% in a thermal basis. Experimental results show that $NO_x$ is 400 ~ 600 ppm, $SO_x$ is 600 ~ 700 ppm, and CO is less than 100 ppm. Experimental results show that stable combustion was achieved for high co-firing ratio of the HCS. Emission of $NO_x$ and $SO_x$ was decreased for higher co-firing ratio in spite of the higher nitrogen contents in the HCS. In addition, it was found that the pollutant emission is affected significantly by composition of the main fuel, regardless of the co-firing ratios.

• Korean Journal of Heritage: History & Science
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• 제47권3호
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• pp.172-187
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• 2014

The purpose of this paper is to examine how the 'tradition' has been identified and used concretely on the protection system of cultural property. Firstly, this paper investigated the historical process and aspects that the 'cultural property' and the 'tradition' combined, each had different meaning at the beginning. And it investigated the linkage of them which effect to the protection system and to each other on the system operated. Then, it pointed out a rift within the discourse of tradition to which the system have held on, and the problems as its result. This paper applied the viewpoint of anti-essentialism that the tradition is presented with hegemonic act to raise the inevitable continuity with the past, instead of the common notion that the tradition is 'everything that is handed down from the past.' Because the cultural property is the product of the state system, to pursne the linkage of it and the tradition is identical to examine how the tradition have been officially defined in the national hegemony. Since the 1920s the tradition has defined as a fixed, essential, pure reality in the changing process of the protection system of cultural property. This essentialist viewpoint about the tradition have been continued as the institutional premise regardless of many critics, raised by studies focusing on the culture and cultural property. But we see now a rift on the discourse of tradition as the intellectual discourse has been supported to the system, that is caused by the fast-changing global economic environment and a rat race around the registration of intangible cultural heritage of UNESCO.

• Korean Journal of Environmental Agriculture
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• 제38권3호
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• pp.205-212
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• 2019

BACKGROUND: This survey conducted on agricultural products in Incheon for the past three years from 2016 to 2018 to detect residual pesticides and to monitor the use of pesticides. METHODS AND RESULTS: Residual pesticides were analyzed for a total of 5,937 agricultural products in Samsan wholesale market, traditional market and large retailers in Incheon. Samples were analyzed by multi class pesticide method using GC-MS/MS, LC-MS/MS, GC-ECD/NPD, and UHPLC. In 59 cases (1.0%) residual pesticides were detected improperly and these cases exceeded maximum residue limits (MRLs). CONCLUSION: The ratios of violative agricultural products were similar each year at approximately 1.0% per year, but the residual pesticide detection rates with the limit included in the samples were shown to be gradually decreasing to 17.9%, 12.6%, and 11.2% annually. The frequency of violative residual pesticides was high in order of Diazinon, Chlorpyrifos, Iprodione, etc. Residual pesticide monitoring might be needed in the future continuously, as violations in agricultural products distributed in Incheon are shown at a similar level every year.

• The Southeast Asian review
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• 제28권2호
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• pp.181-212
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• 2018

In 2017, the government of Duterte, in the second year of the ruling, more strongly promoted peace and order policies and expressed independent diplomacy as the chairman of ASEAN. He continued to fight against drugs and tried to increase his political legitimacy through the punishment for corrupt officials. He also declared martial law in the Mindanao region because of the dissolution of the Maute group, a Muslim terrorist organization, and strengthened counterterrorism cooperation externally. In addition, as to Communist militants, he took the initial reconciliation gesture and promoted peace negotiations, however, concluded the peace tide and started the suppression operation due to a series of bloodshed. He still has a strong drive in peace and order issues, backed up by high support rate, but it is becoming a factor of anxiety as the socioeconomically underprivileged and minority groups are increasingly alienated. As the chairman of ASEAN, Duterte has a certain distance from the United States, which is a firm ally, but has turned to increase familiarity with China and Russia, which can take substantial economic benefits. Through diversifying the external economic support and increase of tax revenue, the priority task was to establish the infrastructure. Although the Philippines, which has a high economic growth rate, has a strong expectation that it can establish a solid infrastructure, tax reforms should be successfully completed in order not to repeat the previous failures, which has traditionally increased foreign debt burden by relying on external resources. It seems that it is necessary to find the meeting point of the foreign policy of Duterte and new Korean government's New Southern Policy, and to find possible economic cooperation policies to improve Philippine infrastructure.

• The Southeast Asian review
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• 제28권4호
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• pp.197-221
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• 2018

The Cambodian People's Party swept all 125 assembly seats with 76.78% of the vote in 2018 general elections. The Cambodian National Rescue Party, having been dissolved by court, was excluded from the election and attempted to nullify the legitimacy of the election by demanding its supporters to boycott the election. The Cambodian People's Party launched a campaign encouraging to vote in a desperate need to thwart the boycott movement. The election then became an unprecedented kind of competition the winner of which is decided not by the percentage of the vote but by turnout. The Cambodian People's Party was the winner with the high turnout of 82.89%, securing the means to defend the legitimacy of the election. The potential supporters of the Cambodian National Rescue Party spread out with about a million voters switching to support the Cambodian People's Party. Over a half million invalid votes that unequivocally voiced opposition to the Cambodian People's Party were not sufficient to deny the legitimacy of the election. Having experienced the fierce competition in the 2013 general elections that threatened to end its rule, the Cambodian People's Party decided to secure its power in the upcoming election and executed a tactic designed to remove the rival party through legal means. Competition being removed, the Cambodian political system decayed back to hegemonic electoral authoritarianism from competitive electoral authoritarianism to which it had mad gradual progress through the general elections in the past.