• Membrane Journal
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• v.18 no.1
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• pp.65-74
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• 2008

NOM and fine particles are the main target materials in water treatment using membranes. Particularly, humic substances extracted from soils are frequently used in many fundamental studies representing natural organic matter in raw water for drinking water treatment. In this study, ultrafiltration (UF) of artificial humic water and natural river water was conducted and the characteristics of removal efficiency and permeability were compared. In the UF of river water, the transmembrane pressure increased in the same pattern with that of 5 mg/L humic water. For the removal of organic matter and fine particles, however, two types of feed water had shown different trends. Kaolin particles and humic acids added to artificial water were better removed, while colloids and organics in natural water were relatively poorly removed. From the $UV_{254}$ and GPC analyses, it seemed that the hydrophobicity and size of humic substances contributed to the greater removal of organic matter. The UF membrane applied for humic water also showed a higher flux recovery by caustic chemical cleaning than that for river water.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.638-646
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• 2018

The purpose of this study was to investigate the long-term habitat morphological alteration resulting from a large dam and weirs in the Tamjin River. To achieve this, we carried out a hydrograph analysis and a substrate size distribution analysis. We also estimated the channel width, bar area and vegetation encroachment using aerial photographs taken before and after the construction of the dam and weirs. The result of the hydrological analysis showed that flooding downstream was greatly reduced with small peaks occurrence after the dam construction. Interestingly, normal hydrographs in the main channel appeared just after tributary conjunction. There was a similar pattern in the substrate size analysis. Despite coarsened substrate just downstream of the dam site, more sand appeared again after introduction of the tributary. However, there was an increase in the bar area downstream of the dam's channels with most bars covered with vegetation. The channel width increased at the upper area of weirs through impoundment, but decreased downstream because of vegetation encroachment. This study indicate that unregulated tributary plays an important role in restoring hydro-physical habitat conditions in mainstream channels below a large dam. However, numerous weirs could be a causal factor to accelerate habitat deterioration in the dam downstream channels.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.7-7
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• 2017

범람파동 개념에 따르면 하도와 홍수터의 횡적 연결성은 하천 생태계의 생물다양성과 생산성 증대에 중요한 역할을 한다. 제방에 의하여 제내지 홍수터가 하도와 차단된 우리나라 하천에서 생태적 서비스를 증대하기 위해서 횡적 연결성을 복원하는 기술 개발이 필요하다. 횡적 연결성의 복원 기술을 개발하기 위해서는 우선 하도와 홍수터 사이에 생태적 연결성의 현황을 파악하고 연결성을 저해하는 요인을 진단하는 평가 기술 개발이 시급히 요청되고 있다. 따라서 본 연구에서는 제방에 의하여 차단된 제내지 하천환경에서 수리적, 생태적 횡적 연결성을 평가하고 진단하는 기술을 개발하고 연결성 회복 방안을 제안하고자 한다. 차단된 제내지 하천환경 평가는 1) 지리정보시스템을 이용하여 차단된 하천공간을 탐색하고, 2) 탐색된 전체 재내지에서 원격평가에 의하여 간편하게 횡적 연결성 평가를 실시하고, 3) 선정된 특정 제내지 대상지에서 현장평가에 의하여 상세하게 연결성을 평가하는 순서로 수행된다. 차단된 하천공간의 획정은 홍수가 범람할 수 있는 제내지 공간을 잠재적 하천공간으로 정의하고 수치표고모델 (DEM)과 하천기본계획의 30년 빈도 홍수위 자료를 이용하여 제내지 홍수터를 탐색하였다. 제내지 홍수터의 원격 연결성평가는 지리정보시스템에서 수치지도와 토지피복도 등 공간자료를 이용하여 수리 및 서식처 환경성, 제방 차단성과 하도 및 육상 연결성을 평가하고 원격평가 결과를 토대로 현장평가 대상지를 선정하였다. 횡적 연결성의 현장평가를 위하여 크게 하도-홍수터 연결성과 제내지 서식처 보존성으로 평가 항목을 선정하였다. 또한 연결성 평가는 수리연결성과 생물연결성으로, 서식처 보존성 평가는 습지유지율, 습지보존성, 육역지보존성을 세부항목으로 구성하였다. 평가 항목별로 5 등급의 평가 기준에 따라서 평가 점수를 부여하고 평가 총점을 산출하여 최종 연결성 평가 등급을 5 단계로 구분하였다. 현장평가를 위한 MS Access 기반 소프트웨어를 개발하여, 데이터 입력과 관리 및 평가 결과 산출과 비교를 편리하게 하였다. 개발된 제내지 하천환경 평가법을 청미천과 만경강에 적용하여 검증하였다. 개발된 평가법을 바탕으로 차단된 제내지 하천환경에서 연결성 회복에 따른 어류와 식생의 분포를 예측하는 수리생태 결합모델을 개발하였다. 먼저 차단된 제내지에서 연결 수로를 복원하여 유속, 수심 분포를 준이차 수리수문 모델로 예측하였다. 예측된 수리 환경에 따라서 지표어종의 서식처 적합도 지수 (HSI)를 이용하여 서식 분포 확률을 모의하였다. 또한 일반화가법모델 (GAM)을 이용하여 환경구배에 의한 우점식생의 분포를 예측하였다. 차단된 제내지 하천환경의 생태적 연계성 평가 기술을 기반으로 제방제거, 제방후퇴, 제방고 하강, 수문 및 연결수로 개선, 생물이동 저해 장벽 제거 등의 다양한 복원기술이 개발되어야 할 것으로 생각된다.

• Journal of Korea Water Resources Association
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• v.38 no.1
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• pp.37-48
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• 2005

The evaluation methods of river naturalness were reviewed, and one of the best methods was applied to three sample rivers-Narinchun, Bokhachun, Anyangchun. As a result, Narinchun with well preserved state, Bokhachun with being to restoration stage from the damaged, Anyangchun with severe damaged state showed 2$^{nd}$ , 3$^{rd}$ and 4$^{th}$ Grade. The application result shows the method is reliable for evaluating the damaged habitat in river. The method was improved on the evaluation items to apply lager river systems. This suggested method have 14 evaluation items with two category-river shape and river environment and five different Grades for evaluation degree according to state of natural closeness. The every 2,000-3,000m along the river system is recommended as the interval of evaluation unit. According to calssification of evaluation items, this method can supply various information related to river environment and ecology such as ecological deformation and diversity, cross sectional structure and continuity of river shapes..

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.3
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• pp.239-245
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• 2014

Complete denture prosthodontics includes replacement of natural teeth and associated maxillary and mandibular structures for full edentulous patients. The final objectives of prosthodontic treatment include esthetic and functional rehabilitation. Because the esthetic demand of senior patients has increased esthetic requirement should not be overlooked in denture treatment. In complete denture treatment, attempts have been made to reproduce tooth wear, arrangement, recession of cervical gingiva, staining, improved gingival shade and so on. This 61 year old female patient came to the Department of Prosthodontics with the chief complaint that dentures made 5 years ago in a local clinic were broken and did not fit well. The patient put more emphasis on fabrication of natural and esthetic dentures than recovery of masticatory function. Remake of maxillary complete denture and mandibular implant retained overdenture was planned. In order to create esthetic and natural contour, Aesthetic Color Set Easy system$^{(R)}$ (Candulor dental GmbH, Wangen, Germany) was used to make complete dentures reproducing various gingival shades. Patient's esthetic satisfaction was high. When complete denture prosthodontics treatment involves appropriate expression of individual characteristics in addition to proper selection of esthetic materials, treatment will give satisfaction to both dentist and patient.

• Journal of Korean Philosophical Society
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• v.142
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• pp.145-164
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• 2017

In his Phenomenology of Perception, Merleau-Ponty raises a question of why he has to ask what phenomenology is again. This study assumes that the question can be answered in a new understanding of the "nature" concept and finds its possible grounds in the nature concepts of Schelling and Merleau-Ponty. Schelling and Merleau-Ponty develop philosophical thinking from a critical point of view on the Cartesian and Kantian philosophies "Thing-in-itself" by Kant is, in particular, one of important questions that has to be answered in the philosophy of Schelling since Kant further solidifies a dualistic world by leaving thing-in-itself. Schelling solves the question with the concept of identity and Merleau-Ponty solves the question with body-subject. What we notice in this article is the understanding of Shelling and Merleau-Ponty about nature. Schelling believes there are the creative activities of unconscious intelligence in nature, but spirit or intelligence in his nature concept cannot induce an existential being. Here we see that Schelling is still beyond the traditional epistemological framework. To restore the original nature of nature, we must begin with an understanding of the totality of nature. Nature must also be explained through relationships with humans. Merleau-Ponty shows the entanglement of nature and spirit through the body-subject. In Merleau-Ponty's phenomenology, the body is the equivalent of nature. Understanding the forces of nature that Schelling and Merleau-Ponty are trying to show, and at the same time explaining the problem of how the mind or human beings emerge from nature, we will be able to discover the true nature of nature.

• Korean Journal of Environment and Ecology
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• v.25 no.2
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• pp.166-174
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• 2011

This study was carried out to investigate the actual vegetation and Degree of Green Naturality(DGN) in Naejangsan National Park in 2010. The actual vegetation of the surveyed site were classified into twelve plant communities and the others. Secondary forest were classified into eight plant communities; Pinus densiflora community, Deciduous broadleaf forest, Quercus mongolica community, etc. Afforested lands were classified into four forest types: P. rigida -P. densiflora forest, P. rigida forest, etc. The area of DGN 8 consisted of 60.58% while the area of DGN 9 consisted of 3.62% when compared with land area in Naejangsan National Park. The exotic plants needs to be managed for recovery of natural landscape and biological diversity in Naejangsan National Park.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.221-226
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• 2009

Six microsatellite DNA markers were used to investigate the genetic variability between wild populations and cultured stocks of olive flounder Paralichthys olivaceus. The average of observed (Ho) and expected heterozygosity (He) ranged from 0.722 to 0.959, and from 0.735 to 0.937, respectively. There was no distinguishable difference between the wild populations and cultured stocks in terms of the observed and expected heterozygosities. However, number of alleles per locus differed markedly between the two fish groups: 19.7 to 21.8 for the wild populations and 12.0 to 14.7 for the cultured stocks. This result gives important information concerning the production of seedling for the improvement of genetic diversity in this species.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.96-103
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• 1999

Restoration of missing oral tissues by using implant therapy is one of viable options in prosthodontic treatment. The purpose of oral rehabilitation are function, esthetics and phonetics. Recently, with the increasing esthetic demand of the patient, dentists and laboratory technicians are more concern ed about natural appearance of implant prostheses. There are so many factors which affect final esthetic results of treatment such a shape, color, proportion, gingival contour etc. To provide natural and vivid looking artificial prostheses to a patient, the careful diagnosis, treatment plan and laboratory Support is crucial. Several cases will be reviewed and discussed in terms of material, gingival shape, contour, speech and connection mode etc. to fabricate natural looking implant prostheses.

• Sijohaknonchong
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• v.30
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• pp.109-146
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• 2009

It is academically recognized that Jeong Wan-Young's sijo better represent Oriental ideas. The purpose of this study is to investigate Taoistic characteristics of Jeong Wan-Young's sijo. This is an effort to succeed and further deepen and extend previous relevant researches. For the purpose, this researcher categorized the poet's sijo in accordance with such characteristics as above mentioned. Findings of the study can be summarized as below. Pieces of Jeong Wan-Young's sijo which are based on Taoistic ideas are largely classified into three groups. First, some pieces of Jeong Wan-Young's sijo represents an orientation of return to hometown which is brought by the sense of loss. His sense of loss is attributed to the facts that his home is not what it was any longer and that he can't return to the old home. To overcome the sense, nevertheless, the poet is dreaming of return to home. The home found in Jeong Wan Young's sijo is something fundamental and original that he purposedly provided against the feeling of loss. It complies with the concept of 'Bokgwigigen(復歸基根)‘ a pursuit of Taoism. Second, other pieces of Jeong Wan-Young's sijo are seeking purity to retrieve childish innocence. Their subjects include the season of spring, dreams of childhood and longing for mother all of which represent the poet's strong desire for such retrieval as above mentioned. It may be said that pursued by that pieces are 'Purity, Feebleness and Smoothness' that are sought by Taoism. Third, other pieces of Jeong Wan-Young's sijo are considering human as a part of nature and seeking human life in harmony with nature. In other words, they are seeking union between human and nature which means going beyond discrimination between self and external objects, that is, 'Mulayangmang(物我兩忘)'. This may refer to return to nature which is the ultimate destination of Taoism.