• The Journal of Korean Philosophical History
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• no.59
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• pp.65-88
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• 2018

Lee Hang Ro's Mind-theory(心說) is an important theory comparable to it of Gi Jeong Jin, Lee Jin Sang and Jeon Woo. In this paper, I examined the influence of the Western-school(西學) in the process of formation of Lee's theory. Since the Western-school had flowed in the beginning of the 17th century, in the 18th century it was subject to Confucian intellectuals along with social stability. However, listed in the 19th century, along with the turmoil of the East Asian international order, the Western-school was also rejected. The Western-school was a tool to analyze the cause of Western invasion(西勢東漸) in him. Lee saw The Western-school from the standpoint of Christianity mainly. Especially Christianity was recognized as a religion that emphasizes God rather than humans. In contrast, Confucianism was understood as a thought system that emphasizes human moral subjectivity rather than God. In this process mind was expanded to the subjectivity of human. However, Lee only emphasized the traditional Confucianism order and ignored the rationality of the Western-school. He could not accommodate western civilization actively and properly respond to the world order in that time. On the other hand, we are now in the era of a new civilization called the Fourth Industrial Revolution. To this the remarks of Lee's Mind-theory will be an important suggestion point for organizing the new civilization actively.

• Journal of the Korean Orthopaedic Association
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• v.52 no.1
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• pp.65-72
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• 2017

Purpose: The purpose of this study was to evaluate the radiologic features of juxtafacet cyst and determine the correlation between these features and clinical outcome. Materials and Methods: We analyzed a total of 23 patients. The degree of facet joint degeneration was classified using the Fujiwara method. The facet joint angles were measured with an magnetic resonance imaging to determine whether there was a difference between the cystic lesion that was occupied and the cystic lesion that was not occupied. Disc degeneration was measured by the Pfirrmann classification method. The clinical result was evaluated using the Oswestry disability index score and visual analogue scale. Results: The L4-5 level of juxtafacet cyst was mostly affected, as found in previous studies. Facet joint arthritis was more severe within the side with the cystic lesion. Significant correlation was found between disc degeneration and juxtafacet joint cyst. All patients underwent wide decompression and fusion. Clinical result was excellent. No patients had signs of recurrence during the follow-up periods. Conclusion: Juxtafacet cyst has a significant correlation with facet joint degeneration. Therefore, aggressive surgical treatment-not just simple cyst excision-should be considered as the treatment option for juxtafacet cyst associated with degenerative lumbar disease.

• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.291-304
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• 2023

Harmful algal blooms (HABs) have become an increasing concern in terms of human health risks as well as aesthetic impairment due to their toxicity. The reduction of water pollutants, especially nutrients from non-point sources in a reservoir watershed, is fundamental for HABs prevention. We investigated the pollutant removal efficiencies of a constructed wetland to evaluate its feasibility as a method for controlling non-point sources located in the Annaecheon stream within the Daecheong Reservoir watershed. The overall removal efficiencies of pollutants were as follows: BOD 14.3%, COD 17.9%, SS 50.0%, T-N 19.0%, and T-P 35.4%. These results indicate that constructed wetlands are effective in controlling pollutants from non-point sources. The seasonal variation in removal efficiency depended on the specific pollutants. The removal efficiencies of BOD, COD, and T-N were stable throughout the year, except during winter, which might have been influenced by lower microorganism activity. In contrast, T-P showed a consistent removal efficiency even during the winter season, suggesting that the wetland can reduce external phosphorus loading to the reservoir. Regarding the effects of pollutant loadings on removal efficiency, the effluent concentrations of all pollutants were significantly decreased compared to those in the influent in case of middle and high loadings. This demonstrates that constructed wetlands can handle high pollutant loads, including the initial runoff during rainfall, to prevent reservoir eutrophication. Despite the various strengths of wetland water purification, there are limitations as passive treatment. Therefore, more case studies should be conducted to suggest optimum operational conditions for constructed wetlands, taking into consideration reservoir-specific characteristics.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.4
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• pp.10-23
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• 2021

During the Japanese colonial period, the palaces of Joseon were damaged in many parts. Changgyeonggung Palace is the most demolished palace with the establishment of a zoo, botanical garden, and museum. During the Japanese colonial period, the palaces of Joseon were damaged in many parts. This study examined the construction process of Jangseogak(Yi Royal-Family Museum), located right next to the Jagyeongjeon site, which was considered the most important space in the Changgyeonggung residential area of royal family zone, through historical materials and field research. Built in 1911, Jangseogak is located at a location overlooking the entire Changgyeonggung Palace and overlooking the Gyeongseong Shrine of Namsan in the distance. Changes in the surrounding space during the construction of Jangseogak can be summarized as follows. First, in the early 1910s, the topography of the garden behind Jagyeongjeon and part of the Janggo were damaged to create the site of Jangseogak. The front yard was built in the front of Jangseogak, and a stone pillar was installed, and a staircase was installed to the south. In the process, the original stone system at the rear of Yanghwadang was destroyed, and it is presumed that Jeong Iljae and other buildings were demolished. Second, in the 1920s, many pavilions were demolished and the zoo and botanical gardens and museums were completed through leveling. After the Jangseogak was completed, the circulation of the Naejeon and surrounding areas was also changed. Cherry trees and peonies were planted in the flower garden around the front yard of Jangseogak and the stairs, and a Japanese-style garden was created between Yanghwadang and Jibbokheon. Third, in the 1930s, the circulation around Jangseogak was completed in its present form, and the museum, Jangseogak, Zoological and Botanical Gardens, and Changgyeonggung, which became a cherry tree garden, were transformed into a Japanese-style cultural park. After that, the surrounding space did not change much until it was demolished. The restoration of the present palace is a long-term, national project of the Cultural Heritage Administration. The results of this study will provide important data for the restoration plan of Changgyeonggung Palace in the future, and it is expected that it will provide additional information to related researchers in the future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4B
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• pp.213-220
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• 2012

Old river channels have been formed by engineering a straight channel in Korea. This can be classified as wetland-type or land-type. The wetland-type old river channel uses parts of agricultural water supply. However, the channels have been neglected since there are problems associated with poor water quality, reduced water level, ecosystem disturbance, etc. Thus, river maintenance through preservation and restoration of old river channel can be very effective in watershed management. To achieve this, functional assessment of wetland-type old river channel is a priority need. This study applied the wetland-type channel in Mangyoung river for functional assessment. It was formed these channels with regard to the following four major criteria (Natureless, Habitat, Water-friendliness and Water quality) and 21 indices. The indices managed by measuring depending in weights. Consequently, wetland-type channel in Mangyoung river was in good condition both natureless and habitat, while it was a fragile environment in water-friendliness and water quality. In particular, the areas where it has insufficiency water and water suffering from eutrophication needs urgent improvement. This results will be used to utilize wetland-type old river channel as watershed management.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.3
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• pp.153-163
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• 2020

Mineral and geochemical analysis were conducted on two sections (~3.5 m) of red-brown claysilt sediments covering the gneiss and granite weathering zones in Suwon-si for establishing Quaternary paleoenvironmental changes in Korea. The sections were divided into four sedimentary layers (Unit 1-4) by vertical changes in mineral composition and chemical composition. The lowermost unit 1 was a sandy sediment with a high K-feldspar content with a significant contribution of weathered bedrock. Unit 2 was a transition layer showing intermediate characteristics. Unit 3 was a reddish brown clay-silt sediment, with a total clay content of 58% on average, and the main clay minerals were illite-smectite mixed layer minerals and hydroxy-interlayered vermiculite/smectite. Unit 3 contained almost no plagioclase, while the content of kaolin minerals derived by the plagioclase weathering was higher than in the other layers. Unit 4 had similar mineral composition and chemical properties to Unit 3, but had a higher content of plagioclase and chlorite and lower content of kaolin minerals. The chemical compositions of the sections were compared with those in other regions of Korea, suggesting the eolian origin of Units 3 and 4. The paleoenvironmental change in the sedimentary section of this region was interpreted as follows. Weathered products of gneiss and granite, which are bedrocks of this region, were eroded and deposited as sandy sediments in the periphery to form the lower layers (Unit 1, 2), followed by the deposition of the claysilty rich eolian sediments (Unit 3) during the glacial. Unit 3 was chemically weathered during the warm humid climate during the last interglacial, developing a reddish brown color. After that, a eolian sediment layer (Unit 4) was deposited during the last glacial.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.2025-2036
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• 2000

A physicochemical process called ultra rapid coagulation(URC) was applied as a pilot scale to recover eutrophicated lake water at Inkyung Lake located on-campus in Inha university. The URC was uniquely designed to completely remove the presence of phosphorus up to 95%, which in turn leading to lessen the level of eutrophication of lake. For a pilot test of period, the lake was restored showing Carlson's Trophic State Index(TSI) of mesotrophic state which accounts for the reduction of total phosphorus and chlorophyll-a down to approximately 55 from 70 and 73, respectively. A residual presence of aluminum and additional coagulants in the effluent was tested for their potential effects on Photobacterium phosphoreum. The effect concentration ($EC_{50}$-15 min) observed in the effluent revealed that the bioactivity of Photobacterium phosphoreum was not influenced by the residual presence of coagulants. After the pilot test of period, the lake was consequently restored as a mesotrophic state in obtaining the second grade of lake water quality. The URC may be further applied for restoration of greater scale of lake in eutrophication.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.251-251
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• 2011

해양 투기가 금지되면서 혐기소화를 통해 최종적으로 발생되는 폐기물 양을 줄이고 메탄 등의 바이오 가스를 얻어 이를 에너지로 얻기 위한 많은 공정들이 현장에 적용되고 있다. 하지만 혐기 소화 과정을 마친 후 유출되는 유출액은 고농도의 유기물질 및 암모니아성 질소, 인산염 등을 다량으로 함유하고 있어 적은 양이라도 하천이나 호수 등에 유입되면 수질 악화와 부영양화를 초래할 위험성이 크다. 이번 연구에서는 음식물류 폐기물로부터 바이오가스를 생산하기 위한 혐기소화 공정에서 발생하는 유출액의 방류수 수질기준 확보와 경제성을 만족시킬 수 있는 처리공정의 상용화 기술을 개발하기 위해 생물학적 처리， 물리 화학적 처리를 통합한 공정을 적용하였다. P건설사 혐기소화 유출액 pilot plant(1 ton/day) 운전 결과 50~70% 로 $NO_2$-N 이 약 1,000 mg/$\ell$정도로 축적되는 현상을 보였으며 상대적으로 $COD_{Cr}$의 농도는 400~600 mg/$\ell$로 C/N 비가 낮아 탈질이 어려울 것으로 판단하였다. 이에 실험실 규모에서의 실험을 진행하였다. $NO_2$-N와 $NO_3$-N을 기준으로 McCarty 양론비 기준 80% 에서 300%까지 메탄올을 주입해 제조 폐수와 실제폐수로 실험을 진행하였고 제조폐수로 실행된 실험에서 아질산 탈질의 효율을 확인하였다. 미생물이 메탄올에 순응 후 완전 탈질에 걸리는 시간은 약 2.5 일로 확인 되었으며 메탄올이 추가로 주입되지 않은 반응조의 $NO_2$-N의 탈질량은 메탄올이 이론값 100% 주입 된 반응조에 비해 30% 이하의 처리 효율을 나타냈다. 이론값을 기준으로 메탄올이 100% 주입된 반응조는 약 96.1%의 탈질 효율을 보였으며 메탄올 순응 후에 약 1.5 일의 HRT가 단축되었기 때문에 메탄올에 장시간 순응 시 탈질 효율이 더 좋아질 것으로 보인다. 아질산탈질에 대한 실험실 규모 연구결과를 토대로 pilot plant에서 재현성 검토를 목적으로 운전을 수행하였다. 무산소조의 HRT는 2.7 일 이었으며 호기조의 HRT는 4.1 일 이었다. 유입수의 평균 $COD_{Cr}$ 농도는 2,878 mg/L, T - N 농도는 2,723 mg/L로 나타났으며 $NO_2$-N 기준 C/N비 1.2-1.8의 메탄올을 주입하였을 때 96% 이상의 탈질율을 보였다.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.414-420
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• 2015

Nitrogen is one of main causes to induce eutrophication of water system and one of contaminants that must be treated for protection of water system. In this study, it was intended to identify a method to increase operation efficiency of municipal wastewater treatment plant (MWTP) by treating high concentration nitrogen. A laboratory scale reactor was operated by using sludge thickener supernatant in the MWTP. During operation of the laboratory scale reactor, it was intended to induce stable nitritation and analyze effects of related operation factors. As results, it was shown that the nitiritation could be induced artificially through control of retention time and sections where the stable nitiritation was induced were identified also. In particular, highly efficient nitrite conversion efficiency near 90% was identified in condition of 1 day retention time. Especially, it was shown that ammonium nitrogen load affected ammonium nitrogen removal efficiency and nitrite conversion efficiency. In the condition of high ammonium nitrogen load, the nitrite conversion efficiency and the ammonium nitrogen removal efficiency decreased. On the contrary in the condition of low ammonium nitrogen load, it was found that the nitrite conversion efficiency decreased. It means that control of ammonium nitrogen concentration and its retention time is needed for the nitritation. It is considered that for the sewage containing high load nitrogen in sludge treatment process as like the sludge thickener supernatant, the nitritation can be applied, which can be suggested as a modification method of MWTP.

• Journal of Wetlands Research
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• v.20 no.1
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• pp.54-62
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• 2018

Nutrients generated from various land uses lead to eutrophication during the influx of water, and it is necessary to apply the LID techniques to reduce nutrients from nonpoint sources in order to mitigate the occurrence of the algal bloom. This study was carried out to derive the design factors of hybrid artificial wetland (HCW) to increase the removal efficiency of nutrients. HCW system was constructed in the year 2010 for the treatment of rainfall runoffs from parking lots and roads composed of 100% impervious floors in the Cheonan campus of Kongju University. The average nutrients removal efficiency of TN and TP was 74% and 72%, respectively. Both TN and TP removal efficiencies were higher than those of free surface wetlands and subsurface flow wetlands due to activated physical and ecological mechanisms. The critical design parameters for the efficient nutrients removal in the artificial wetlands were the ratio of the surface area to the catchment area (SA/CA), land use, the rainfall runoff, and the rainfall intensity. The optimal carbon to nitrogen (C/N) ratio was estimated at 5: 1 to 10.3: 1. The results of this study can be applied to the efficient design of hybrid artificial wetlands to treat nutrients in urban runoff with high efficiency.