• 제목/요약/키워드: Natural History

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자동차 엔진 텐션베어링에 대한 구조해석 (Structural Analysis on Tension Bearing of Automotive Engine)

  • 조재웅;한문식
    • 한국기계가공학회지
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    • 제11권5호
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    • pp.21-28
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    • 2012
  • This study analyzes about automotive engine tension bearing through the structural analyses of fatigue and vibration. Maximum equivalent stress is shown at the lower of tensioner. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to $-10^{6}MPa$, the possibility of maximum damage becomes 3%. This stress state can be shown with 6 times more than the damage possibility of 'SAE Bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the design of tension bearing by investigating prevention and durability against its damage.

Neo-Catastrophism and a New Global Interpretation of History

  • Yi, Tae-Jin
    • Asian review of World Histories
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    • 제1권1호
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    • pp.85-116
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    • 2013
  • The theory of terrestrial impact which has been developed by the astronomy scientists since 1970s is employed for this article in a new angle that atmospheric conditions of our planet should be adopted in the interpretation of the history of mankind. Large and small terrestrial impacts must be acknowledged as key tasks in terms of the study of 'world history'. The Society of Interdisciplinary Studies has already advocated that the 'Bronze Age Civilization' was strongly influenced by the long term terrestrial impact phenomena. Based on historical materials from Korea, the present study was able to identify the years 680-880, 1100-1220, 1340-1420, and 1490-1760 as periods in which territorial impacts occurred.

불도저의 구조해석에 의한 내구성 연구 (Study on Durability by Structural Analysis of Bulldozer)

  • 한문식;조재웅
    • 한국생산제조학회지
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    • 제20권3호
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    • pp.239-244
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    • 2011
  • This study analyzes the behaviors on stress, fatigue and vibration about bulldozer in operation. Maximum equivalent stress is shown with the frequency of 100 Hz in case of the harmonic vibration analysis applied with force. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to -105MPa and the amplitude stress of 0 to $1.617{\times}105MPa$, the possibility of maximum damage becomes 3.23%. This stress state can be shown with 5 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the design of bulldozer by investigating prevention and durability against its damage.

Goniotrichopsis reniformis (Kajimura) Kikuchi comb. nov. (Stylonematales, Rhodophyta) from Japan

  • ;;;신종암
    • ALGAE
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    • 제21권2호
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    • pp.185-191
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    • 2006
  • The morphology and life history of Stylonema reniforme Kajimura (Stylonematales, Rhodophyta) from Japan were investigated and its taxonomic placement was discussed. This species has 6-30 discoid chloroplasts devoid of a pyrenoid in each cell. This is a typical feature of the genus Goniotrichopsis. The species reproduced only by monospores, which were formed by the direct transformation of the vegetative cells similar to the type species Goniotrichopsis sublittoralis Smith. Goniotrichopsis reniformis (Kajimura) Kikuchi comb. nov. was proposed. The asexual life history of the present species was completed in 3-10 weeks at $15-20^{\circ}C$ in culture.

천연염색을 이용한 제품디자인 개발 (Design development through natural dyeing)

  • 박영선
    • 복식문화연구
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    • 제21권3호
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    • pp.394-400
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    • 2013
  • At a time when the demand for environmentally friendly products is soaring, the fashion industry is following suit. The industry is showing particular interest in natural-dyed products. Against this backdrop, this study conducted a literature review on the history of natural dyeing for textiles and on the types of natural dyes. In addition, this study identified recent trends in the fashion industry and applied the findings from the literature review to those trends. Through this process, possibilities for new designs were suggested. This study proposed designs for various items-t shirts, one-piece dresses, blouses, skirts, and knitwear-by using threads and textiles dyed from mugwort, Polygonum indigo, safflowers, Lithospermum erythrorhizon, and Sophora japonica flowers. This study is also meaningful in that it broadens the boundaries of design for natural-dyed fashion products. To that end, various designs were attempted by combining natural-dyed textiles or knits with leather, denim, and fur.

Genomic Structure of the Luciferase Gene in the Hotaria Firefly

  • Choi, Young-Su;Bae, Jin-Sik;Lee, Kwang-Sik;Kim, Ik-Soo;Kim, Jong-Gill;Kim, Keun-Young;Suzuki, Hirobumi;Lee, Sang-Mong;Sohn, Hung-Dae;Jin, Byung-Rae
    • 한국응용곤충학회:학술대회논문집
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    • 한국응용곤충학회 2001년도 추계 합동 심포지엄 및 학술발표대회
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    • pp.140-141
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    • 2001
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부분 심내막상 결손증의 치험 1예 (Partial Endocardial Cushion Defect with Unusual Clinical Course)

  • 이철주
    • Journal of Chest Surgery
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    • 제13권3호
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    • pp.237-242
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    • 1980
  • This is a case report of spontaneous regression of elevated pulmonary vascular resistance after the age of 6 years in a patient with partial endocardial cushion defect. The patient was first evaluated and considered to be highly risky for surgical correction because of obstructive type of pulmonary hypertension and presisting congestive heart failure at the age of 6 years, during which time medical treatment for congestive heart failure and sufferring from respiratory infection were only provided. Finally the patient was reevaluated at the age of 16 years, in January of 1980 when cardiac catheterization was revealed markedly reduced pulmonary vascular resistance and pulmonary hypertension as well. The patient was operated upon with uneventful postoperative recovery. So we report this case with review of the literatures regarding natural history regarding natural history of partial endocardial cushion defect.

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미분적분학과 자연주의 미술 (Differential$\cdot$Integral Calculus and Natural Arts)

  • 계영희
    • 한국수학사학회지
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    • 제18권2호
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    • pp.31-42
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    • 2005
  • 르네상스 시대가 도래하자 고대 그리스와 로마 문화의 부흥으로 유클리드 기하학이 다시 연구되고 실험과 관찰의 정신이 대두되었다. 이는 곧 근대의 정신인 것이다. 본 논문에서는 17, 18세기에 지식인이 추구했던 가치가 운동, 속도, 빛이었으므로 수학에서 미분적분차이 발명되고, 미술에서는 빛의 화가, 순간의 화가를 탄생시킨 근대의 시대정신과 사회적인 배경을 주목한다.

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퇴계(退溪)의 건축관(建築觀)과 도산서당(陶山書堂) (Toege and the Architecture of Dosan Sodang)

  • 김동욱
    • 건축역사연구
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    • 제5권1호
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    • pp.18-38
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    • 1996
  • Dosan Sedans was built in 1560, when Toege I Whang(1500-1571) was 60, as a place in which to study and teach disciples. The building was built to a humble 3-kan system which was a popular form of sodang in the 16th century, There found an enlargement of space by attaching outer walls around three sides which was designed by Toege himself. Minimum in space, moderation in form, conrol of embellishment, hermit scholar's aethetics became basic concept of the architecture of Dosan Sodang. After completion of sodang, Toege wrote many poems about pond, walls, flower bed and natural surroundings like sheer cliff, winding river and even rural daily life of villagers around the building. It could be sud that ,for Toege, architecture was cogniged as a whole complex of building and its surrounding natural, artificial and human circumstances.

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Current Concept of Management of Partial-thickness Rotator Cuff Tear

  • Lim, Tae Kang;Park, Jae Hyun
    • Clinics in Shoulder and Elbow
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    • 제17권4호
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    • pp.209-217
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    • 2014
  • Most studies on the pathophysiology, natural history, diagnosis by imaging and outcomes after operative or nonoperative treatment of rotator cuff tear have focused on those of full-thickness tears, resulting in limited knowledge of partial-thickness rotator cuff tears. However, a partial-thickness tear of the rotator cuff is a common disorder and can be the cause of persistent pain and dysfunction of the shoulder joint in the affected patients. Recent updates in the literatures shows that the partial-thickness tears are not merely mild form of full-thickness tears. Over the last decades, an improved knowledge of pathophysiology and surgical techniques of partial-thickness tears has led to more understanding of the significance of this tear and better outcomes. In this review, we discuss the current concept of management for partial-thickness tears in terms of the pathogenesis, natural history, nonoperative treatment, and surgical outcomes associated with the commonly used repair techniques.