• Title/Summary/Keyword: 이승종

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Comparison of Design Concepts for Four Different Entrained-Bed Coal Gasifier Types with CFD Analysis (CFD 해석을 통한 4종의 건식 분류층 석탄가스화기 설계개념 비교)

  • Yun, Yongseung;Ju, Jisun;Lee, Seung Jong
    • Applied Chemistry for Engineering
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    • v.22 no.5
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    • pp.566-574
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    • 2011
  • Coal gasifier is a key component for achieving high efficiency in integrated gasification combined cycle and indirect coal liquefaction. Although there have been several successful coal gasifiers that were commercially proven, many different design configurations are still possible for a simple and reliable gasifier operation. Four different gasifier design concepts of dry-feeding were compared in terms of residence time, exit syngas temperature and syngas composition. First, cold-flow simulation was applied to pre-select the configuration concepts, and the hot-flow simulation including chemical reactions was performed to compare the concepts at more actual gasifier operating conditions. There are many limitations in applying CFD method in gasifier design, particularly in estimating slag behavior and slag-tap design. However, the CFD analysis proved to be useful in comparing the widely different gasifier design concepts as a pre-selection tool.

Prediction of Potential Distributions of Two Invasive Alien Plants, Paspalum distichum and Ambrosia artemisiifolia, Using Species Distribution Model in Korean Peninsula (한반도에서 종 분포 모델을 이용한 두 침입외래식물, 돼지풀과 물참새피의 잠재적 분포 예측)

  • Lee, SeungHyun;Cho, Kang-Hyun;Lee, Woojoo
    • Ecology and Resilient Infrastructure
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    • v.3 no.3
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    • pp.189-200
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    • 2016
  • The species distribution model would be a useful tool for understanding how invasive alien species spread over the country and what environmental variables contribute to their distributions. This study is focused on the potential distribution of two invasive alien species, the common ragweed (Ambrosia artemisiifolia) and knotgrass (Paspalum distichum) in the Korean Peninsula. The maximum entropy (Maxent) model was used for the prediction of their distribution by inferring their climatic environmental requirements from localities where they are currently known to occur. We obtained their presence data from the Global Biodiversity Information Facility and the Korean plant species databases and bioclimatic data from the WorldClim dataset. As a results of the modelling, the potential distribution predicted by global occurrence data was more accurate than that by native occurrence data. The variables determining the common ragweed distribution were precipitation of the driest month and annual mean temperature. Both annual and the coldest quarter mean temperatures were critical factors in determining the knotgrass distribution. The Maxent model could be a useful tool for the prediction of alien species invasion and the management of their expansion.

Multiple Xanthomatosis in Familiar Hypercholesterolemia Patient - A case report - (가족성 고콜레스테롤혈증 환자에서의 다발성 황색종 - 1례 보고 -)

  • Rhee, Seung-Koo;Lee, Hwa-Sung;Moon, Chan-Woong
    • The Journal of the Korean bone and joint tumor society
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    • v.6 no.1
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    • pp.41-46
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    • 2000
  • We experienced the case of familiar hypercholesterolemia with multiple xanthomas which was treated by combined surgical and medical therapy. He was 26-year-old male patient of familiar hypercholesterolemia with multiple xanthomas in 22 sites on whole body, and was treated by 17 surgical excisions of the xanthomas and by medical therapy of the hypercholesterolemia. There was a normal healing process of the surgical wounds. Continual postoperative medical therapy of the hypercholesterolemia was done. There was no recurrence of the symptoms during more than 13 months of follow-up. But the serum level of the cholesterol was not lowered significantly, so we are treating him with drug therapy. Familial hypercholesterolemia is caused by a specific disorder of lipid metabolism, and is characterized by increased LDL cholesterol, tendon xanthomas, coronary disease associated with autosomal dominant transmission. Xanthomas usually appear in the second decade of life with familiar hypercholesterolemia which may have high risk for premature coronary atherosclerosis, which might be prevented with early diagnosis and medical treatment. So, orthopedic surgeons do not only excise the xanthomatosis surgically but also can diagnose the underlying hypercholesterolemia.

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용담댐 건설로 인한 금강 상류의 하천환경변화 분석 III - 생태변화분석 -

  • 이승현;정동양;정승권
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.977-981
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    • 2004
  • 댐 건설로 인한 인위적인 당류량 조절은 댐 하류지역에서 홍수 피해저감에 기여하고 있지만, 자연적인 유출 리듬이 파괴되며 유속, 수심, 건조지 확대와 같은 수량의 변동과 용존산소량, 영양염류, pH 같은 수질 변화, 그리고 하천 형태의 변화를 가져오게 된다. 하천에서의 생물 서식공간은 산림 등 육지 지역과는 단리 무엇보다 하천의 유체역학적인 영향을 받아 형성되고 발달한다. 인위적인 댐 방류량은 하류지역의 건조 면적을 증가시키기 때문에 하천 형태가 변화하는 결과를 가져오고, 댐 건설로 인하여 자연적인 홍수 유출이 급감하게 되면 건조면적이 확산되어 수변식물과 어류의 서식처 환경 변화를 유발하여 기존의 생태 균형이 파괴될 것으로 예상된다. 지금까지 국내에서 댐 건설로 발생되는 피해를 분석한 연구들을 분석해 보면, 수량 및 수질 변화에 대하여는 많이 제시하고 있지만 생태변화에서는 정량적인 피해를 제시한 연구가 없기 때문에 용담댐 건설로 인한 하류구간의 수변식물과 어류를 대상으로 정량적인 피해를 분석하는 것이 매우 필요하다. 따라서 본 연구에서는 용담댐 건설로 인한 인위적인 유출량 감소가 댐 하류 8km 구간에서 수변식물과 어류에 미치는 영향을 예측하고자 하였으며, 이를 위해 용담댐 기점 약 5km지점(조사지점 I)인 전북 진안군용담댐 감동리 주변지역에서 수변식물과 어류 군집에 내하여 2003년 5월부터 7월까지 3회 조사하였고, 추가로 약 1km지점(조사지점II)인 전북 진안군 용담면 월계리 주변지역에서 수변식물을 중심으로 2003년 9월에서 10월까지 2회 조사하였다. 수변식물은 조사지점(I)인 5km지점에서는 전체적으로 13과 21종으로, 벼과가 4종, 국화과가, 3종, 버드나무과, 콩과, 마디풀과가 2종씩, 바늘꽃과, 속새과, 십자화과, 장미과, 사초과, 삼과, 현삼과, 닭의장풀과가 각 1종씩 조사되었으며, 조사지점(II)인 1km지점에서는 15과 26종으로, 벼과가 4종, 마디풀과, 국화과가 3종, 버드나무과, 십자화과, 콩과가 2종씩, 바늘꽃과, 속새과, 자라풀과, 장미과, 사초과, 백합과, 현삼과, 골풀과, 닭의장풀과가 각 1종씩으로, 조사지점( I )보다 좀 더 많은 종이 분포하는 것으로 조사되었다. 또한 어류는 조사지점( I )에서 3회에 걸쳐 총 396개체가 채집되어 3목 8과 21종이었다. 이 중 한국 고유종은 11종이었고, 외래 어종은 검정우럭과 2종이 조사되었으며, Zacco platypus(피라미), Zacco temmincki(갈겨니), Acheilongnathus koreanus(칼납자루), Odontobutis platycephala(동사리), Coreoleuciscus splendidus(쉬리) 순으로 분포하고 있었고, Acheilognathus signifer(묵납자루)는 댐 건설 전에는 많이 분포하였으나 현장조사에서 서식을 확인 할 수 언어 개체수의 큰 감소내지 멸종된 것으로 추정되었다.

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Succession and Appearence Species of Marine Benthic Diatoms on Wave Plates of Indoor Culture Tank (Short-term Observation) (실내 수조에 설치한 파판에서의 해양 부착 규조의 단기간 천이 및 출현종)

  • Wi Chong Hwan;Kim Hyeung Sin;Lee Sung Ju;Jung Min Min;Kim Tae Ik;Kim Byoung Hak;Huh Young Baek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.5
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    • pp.476-479
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    • 2002
  • We observed the succession and appearence species of the marine benthic diatoms for the effective seed production of shellfish culture on wave plates in indoor mass culture tanks. Every five days, the existence species and densitiy of diatoms were counted during the 20 culture days. Experimental conditions were 8.5 $\pm$ 0.3$^{\circ}C$ of water temperature, 1.0250$\~$1.0260 of specific gravity, 2,200$\~$13,000 lux of light intensity. The total density of appearence species was rapidly increased with the lapse of time. However, the number of appearence species decreased on the 20th day. The diatoms observed were 10 species; Navicula sp. of, viridula, Cylindrotheca closterium, Licmophora sp., Pleurosisma normnii, Bacillaria Paradoxa Asterionella glacialis, Stephanopuis sp. cf, turris, Entomoneis sp., Odontella aurita and Cocconeis sp, cf, scutellum. Of them, Navicula sp, of, viridula was most dominant throughout the experiment.

Species and Distribution of Native Wild Mushrooms Traditionally using in Jeju Island (전통적으로 이용되는 제주 야생버섯의 종류와 분포)

  • Ko, Pyung-Yeol;Lee, Seung-Hak;Jeun, Yong-Chull
    • The Korean Journal of Mycology
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    • v.40 no.1
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    • pp.39-43
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    • 2012
  • The knowledge of native wild mushrooms traditionally using in Jeju Island, that have specific native environment and various biodiversity, was investigated. From Jeju and Seogwipo cities including 7 provinces 4 locals, so total 50 villages, data was collected in the entire area and voice of the 93 elderly people between the age of fifty and ninety were recorded. As a result, total 23 native wild mushrooms were used in which 2 species were poisonous mushrooms, 7 species were medicinal mushrooms, 2 species was used for folk religion, 2 species were not used for living but for attention and 12 species were edible mushrooms. Also, a total of 267 cases of traditional knowledge was collected, in which 197 cases were about edible mushrooms for 12 species, 43 cases were about poisonous mushrooms for 2 species, 16 cases were about medicinal mushrooms for 7 species. Interestingly, the fortune for agriculture was told depending on spore mass release of Cyathus stercoreus which grows in animal feces and compost. It is considered as the distinctive traditional knowledge of Jeju Island.

Secondary Chondroblastic Osteosarcoma from Polyostotic Fibrous Dysplasia Initially Misdiagnosed as Low Grade Chondrosarcoma Provoking Fallacy in Treatment Strategy (저 악성도 연골육종으로 악성 변화한 섬유성 이형성증으로 오진하여 치료방침의 오류가 발생한 연골 모세포형 골육종 - 증례 보고 -)

  • Lee, Seung-Jun;Koh, Jae-Soo;Won, Ho-Hyun;Jeon, Dae-Geun
    • The Journal of the Korean bone and joint tumor society
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    • v.14 no.1
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    • pp.62-67
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    • 2008
  • Malignant degeneration of fibrous dysplasia is rare and involves transformation into osteosarcoma, fibrosarcoma and chondrosarcoma. The most frequent sites involved in malignant transformation were craniofacial bones, proximal femur, humerus, pelvis, tibia and scapula in a decreasing order of frequency. An 41-year-old man with a history of polyostotic fibrous dysplasia presented with increasing left arm pain. Plain radiograph showed expansile destructive lesion along the humeral shaft. As initial biopsy report was low grade chondrosarcoma, he underwent marginal resection. However, he developed local recurrence 7 month later and subsequent pathologic finding was chondroblastic osteosarcoma. We report one case of secondary chondroblastic osteosarcoma from polyostotic fibrous dysplasia initially misdiagnosed as low grade chondrosarcoma that caused fallacy in treatment strategy.

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Volatile Component Analysis of Commercial Japanese Distilled Liquors (Shochu) by Headspace Solid-Phase Microextraction (헤드스페이스 고체상미량추출(Solid-Phase Microextraction)을 이용한 시판 일본소주의 휘발성 향기성분 분석)

  • Shin, Kwang-Jin;Lee, Seung-Joo
    • Korean Journal of Food Science and Technology
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    • v.47 no.5
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    • pp.567-573
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    • 2015
  • In this study, volatile compounds in nine commercial Japanese distilled liquors (Shochu) were isolated by headspace solid-phase microexrraction (SPME) and analyzed by gas chromatography (GC) and GC-mass spectrometry (MS). A total of 76 volatile components, including 48 esters, 13 alcohols, and 15 miscellaneous components, were identified. Esters and alcohols constituted the largest groups of quantified volatiles. Differences in volatile components among the distilled liquors and possible sample grouping were examined by applying principal component analyses to the GC-MS data sets. The first and second principal components explained 77.92% of the total variation across the samples. The samples using barley koji showed higher overall concentrations of total volatile components. Additionally, the principal component analysis did not reveal any sample grouping based on the raw material used.

The freshwater Ichthyofauna of Deogyusan National Park, Enclosing Baekdudaegan (백두대간에 포함되는 덕유산 국립공원 일대 수계의 어류상에 관하여)

  • Lee Seung-Hwi;Kwon Eun-Ho;Shin Young-Hee
    • Korean Journal of Environment and Ecology
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    • v.18 no.3
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    • pp.326-332
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    • 2004
  • A study of freshwater ichthyofauna was conducted in order to clarify its significance at 14 upstream sites in Muju, Jangsu, Geochang and Hamyang districts in Deogyusan National Park, enclosing Baekdudaegan. The freshwater fish fauna of the Park was measured at the 14 sampling locations from May 2003 to September 2003. The fifteen species gauged included four Korean endemic species and or subspecies (Squalidus japonicus coreanus, Iksookimia longicorpa, Coreoperca herzi, Odontobutis platycephala). Fourteen species were found in the Keum River and seven species in the Nakdong River. However, common species were Punchocypris, Rhynchocypris oxycephalus, Zacco temmincki, Misgurnus anguillicaudatus, Coreoperca herzi, and Odontobutis pzatycephala. The dominant species of these regions were Zacco temmincki and Rhynchocypris oxycephalus. Past studies conducted in Baekdudaegan mostly concernedflora and vegetation. In the future, new study concepts for stream corridors involving both animal and plant should be introduced.

RETROPHARYNGEAL AND MEDIASTINAL ABSCESS SECONDARY TO ODONTOGENIC INFECTIONS : REPORT OF THREE CASES (치성감염에 의해 발생된 후측인두부 및 종격동 농양)

  • Park, Mun-Seong;Kim, Chang-Lyong;Lee, Seung-Ho;Jung, Joo-Sung;Jeong, Jong-Cheol;Kim, Keon-Jung;Ryu, Sun-Youl
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.18 no.4
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    • pp.626-635
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    • 1996
  • Odontogenic infections are usually locally confined, self-limiting processes. However, under certain circumstances, they may break through the bony, muscular, and mucosal barriers and spread into contiguous fascial spaces or planes far from the initial site of involvement, resulting in severe life-threatening complications, such as retropharyngeal spread, suppurative mediastinal extension, airway obstruction, pleuropulmonary suppuration, and hematogenous dissemination to distant organs. The mortality arte for mediastinitis from odontogenic infection ranges from 40% to 60%. Therefore rapid evalution and treatment is essential with a combination of life support, antibiotic therapy, and surgical intervention. Recently, we experienced three cases of retropharyngeal and mediastinal abscesses secondary to odonogenic infections. In all patients, early diagnosis was possible by CT scanning and physical examination. The prognosis was good in all patients by using urgent aggressive surgical and antibiotic therapy.

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