• 제목/요약/키워드: OWE

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진동수주형 파력발전장치 공기챔버의 파력에너지 흡수효율 (Wave Energy Absorption Efficiency of Pneumatic Chamber of OWC Wave Energy Conveter)

  • 홍기용;신승호;홍도천
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2007년도 춘계학술대회
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    • pp.621-625
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    • 2007
  • Oscillating wave amplitude in a bottom-mounted owe chamber designed for wave energy converter is investigated by applying characteristic wave conditions in Korean coastal water. The effects of shape parameters of OWC chamber in a view of wave energy absorbing capability are analyzed. Both experimental and numerical approaches are adopted and their results are compared to optimize the shape parameters which can result in a maximum power production under given wave distribution. The experiment was carried out in a wave flume under 2-D assumption of OWC chamber. In numerical scheme, the potential problem inside the chamber is solved by use of the Green integral equation associated with the Rankine Green function, while outer problem with the Kelvin Green function taking account of fluctuating air pressure in the chamber. Air duct diameter, chamber width, and submerged depths of front skirt and back wall of chamber changes the magnitude and peak frequency of wave absorption significantly.

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3D simulation of railway bridges for estimating fundamental frequency using geometrical and mechanical properties

  • Moazam, Adel Mahmoudi;Hasani, Nemat;Yazdani, Mahdi
    • Advances in Computational Design
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    • 제2권4호
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    • pp.257-271
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    • 2017
  • There are many plain concrete arch bridges in Iran that have been used as railway bridges for more than seventy years. Owe to the fact that these bridges have not been designed seismically, and even may be loaded under high-speed trains, evaluation of fundamental frequencies of the bridges against earthquake and high-speed train vibrations is necessary for considering dynamics effects. To evaluate complex behavior of these bridges, results of field tests are useful. Since it is not possible to perform field tests for all arch bridges, these structures should be simulated correctly by computers for structural assessment. Several parameters are employed to describe the bridges, such as number of spans, length of spans, geometrical and material properties. In this study, results of field tests are used for modal analysis and adapted for 64 three dimensional finite element models with various physical parameters. Computer simulations show length of spans has important effect on fundamental frequencies of plain concrete arch bridge and modal deformations of bridges is in longitudinal and transverse directions. Also, these results demonstrate that fundamental frequencies of bridges decrease after increasing span length and number of spans. Plus, some relations based in the number of spans (n) and span length (l) are proposed for calculation of fundamental frequencies of plain concrete arch bridge.

만형자(蔓荊子), 시호(柴胡)의 알레르기성 비염에 대한 효과 (The Effects of Victicis Fructus & Bupleuri Radix on the Allergic rhinitis)

  • 남혜정;박외숙;김희정;김규석;차재훈;김윤범
    • 한방안이비인후피부과학회지
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    • 제19권2호
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    • pp.40-49
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    • 2006
  • Background and Objectives : In oriental Medicine, there is a concept that herb works only in it's own specific site called 'Guikyung(歸經)'. If two herbs have same effect and different Guikyung, two herbs would work at different site respectively. so we want to prove that whether Guikyung has significance or not in experimentally. Methods : In order to investigate the effects of Victicis Fructus & Bupleuri Radix on the Allergic rhinitis, BALB/c mouse was used. Control and experimental group 1, 2 were induced allergic rhinitis. Experimental group 1 was administered Victicis Fructus for 28 days and group 2 was administerd Bupleuri Radix for same period. WBC, neutrophil, lymphocyte, monocyte, IL-4 and $IFN-{\gamma}$ were measured and histological examination was performed. The statistical significance was examined by Independent Samples T test. Results : 1. WBC, neuoophil, lymphocyte, monocyte, IL-4 and $IFN-{\gamma}$ showed no statistically significant differences in three groups. 2. Histological examination had no differences in three groups. Conclusion: Victicis Fructus & Bupleuri Radix have no effect on allergic rhinitis and the reason is estimated that Guikymg plays a important roll to determine the effect of herb from the viewpoint of oriental medicine.

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집합주택의 수납공간 크기와 생활태도 및 의식의 상관관계에 관한 연구 - 일본에서의 임대주택의 경우 - (Correlation of size of storage space with purchase pattern of living goods - rental apartment in Japan)

  • 최재순
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 1991년도 학술발표대회논문집
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    • pp.19-28
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    • 1991
  • The present state of possesion of durable consumer's goods in on family in Korean is could be similar with that of about 25 years ago in Japan. Korea meet a period of high rate of economic growth, Japan had already experienced this 25 years ago. It would be important to predict and plan the storage space in the planning house since purchase of durable consummers' goods increase greatly as the rapid economic growth. In order to grasp the dweller's way of thinking and an attitude of living in small size house in Japan, questionaire owe prepared focusing on the "small space", possession of excess living goods and dweller's state of living. From the analysis of the answers for questionaire, the result is as follows. (1) Most of dweller's conclude that the reason of the disorder in their house is that their house in too small, so that they think the part of thier living goods must be disposed. This concept is also available even when they buy new living goods. (2) Disposal of living goods not in use, restraint of buying those are considered inevitable. In addition, changing of place of furnitures is also introduced. (3) The dweller living under 50m2 area dosen's not consider the disorder the house by the living goods. they have interest in how the tradition could be kept their home.

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자가 콜라겐주입술을 이용한 성대구증환자의 치료 (Sulcus Vocalis Treated with Autologous Collagen Injection)

  • 최홍식;이준협;정유삼;임영창;김광문
    • 대한후두음성언어의학회지
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    • 제9권2호
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    • pp.128-133
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    • 1998
  • Background and Objectives : Despite of numerous treatment modalities for glottic insufficiency, it still remains unresolved problem. Recently, autologous collagen injection was introduced as a new treatment for glottic insufficiency. This study was attempted to evaluate the efficacy of this treatment modality. Materials and Methods : Ten patients diagnosed as symptomatic sulcus vocalis with glottic insufficiency and agreed with this procedure were selected. Injectable collagen was obtained from the patient's dermis. It was injected into the pathologic area of the vocal fold. After injection, 4 of 10 patients were 1311owe4 up more than 5 months, and their voice were evaluated prior to injection and at 5 months after injection, using subjective, perceptual, aerodynamic, acoustic and videostroboscopic assessments. Results : In the aerodynamic assessment, 2 of 4(50%) patients was improved in MFR(mean flow rate), but no change was noted in MPT(maximum phonation time). In the acoustic assessment, no definite improvement was noted. In the subjective and perceptual assessments, 2 of 4(50%) patients was improved. In the videostroboscopic assessment, chink was reduced but still remained. Serious complication was not noted. Conclusion : Autologous collagen injection was reported as ideal treatment for glottic insufficiency, but our results were relatively unsatisfactory. But considering that our study is preliminary, it is too hasty to determine the efficacy of autologous collagen injection. We think that further study is required.

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통기성 필름 제조 공정의 전과정 평가 (Life Cycle Assessment on Process of Breathable Film Production)

  • 안중우
    • 청정기술
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    • 제23권4호
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    • pp.388-392
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    • 2017
  • 본 연구에서는 통기성 필름의 제조 공정에 대한 환경영향 특성을 분석하기 위해 전과정평가를 수행하였다. 특성화와 정규화 결과, 영향범주 별 환경영향은 지구온난화가 약 97%. 인간독성 2%의 기여도를 나타났다. 주요 기여도는 투입물인 고밀도 폴리에틸렌(HDPE)과 폴리프로필렌(PP) 그리고 에너지인 전력으로 나타났다. 세부 공정에서는 혼합단계(Mixing)가 57%, 부착단계(Lamination) 29% 압출단계(Extruder) 10% 순으로 높은 환경영향 기여도를 보였다. 환경 영향을 개선하기 위해서는 전력 사용량을 감소시키거나 원재료인 HDPE나 PP를 제외한 수율 향상을 고려한 새로운 공정 시스템 설계가 필요하다.

지루성 피부염의 최신 지견 (Recent Advances in the Seborrheic Dermatitis)

  • 차재훈;남혜정;김희정;박외숙;김규석;김윤범
    • 한방안이비인후피부과학회지
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    • 제19권3호통권31호
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    • pp.118-133
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    • 2006
  • Seborrheic dermatitis is characterized by the appearance of red, flacking, greasy lesions in regions rich in sebaceous glands. There are various opinions about the relation between seborrheic dermatitis and dandruff. Considering all available data, we consider seborrheic dermatitis and dandruff to be differing severity manifestations of similar origin. The known etiologies of seborrheic dermatitis are the abnormality of lipid and hormnes, Malassezia species, immune response. We recently focus on the relation between seborrheic dermatitis and HIV positive and AIDS patients, seborrheic dermatitis and neurological disease. The treatments of seborrheic dermatitis include topical treatments, oral treatments. There are non-specific agents, antifungal medication, corticosteroids in the topical treatments. Narrow band UVB and oral medications are known as the prophylaxis of seborrheic dermatitis but we need further study. In traditional korean medicine, the literature studies and case reports have been published. But we don't know what herbal medicine has antifungal effect against Malassezia species. So we should discriminate herbal medicines which have antifungal effect against Malassezia specieses. Then we could treat seborreic dermatitis by traditional korean medicine effectively.

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천수만 간월도층의 퇴적후 변형상(cryoturbation)으로 해석되는 제4기 최후빙기의 한 반도 서해안의 고환경 (The Paleoenvironment(the LGM time) of the Western Coastal Area of the Korean Peninsula (eastern margin of the yellow sea)based on characteristic Cryoburtation Evidence from the kanweoldo Deposit Cheonsoo Bay West Coast of Korea.)

  • 박용안
    • 한국제4기학회지
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    • 제9권1호
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    • pp.43-60
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    • 1995
  • The Kanweoldo Deposit in the Cheonsoo Bay western coast of Korean Peninsula is considered to be influenced by severe freezing condition under cold humid environment of the last glacial age. The evidence of severe freezing in the some upper part of the fine-grained Kanweoldo Deposit is characteristically irregular wavy la-mellar structure with the interval of 2∼8mm. In particular lamina show very compacted fabrics composed of rounded or spheroidal discrete aggregates covered by silt caps. Such laminar structure and associated micro-fabrics might owe to soil freezing such as ice segregation in lens form cryophoresis pressure from growing ice and disturbance by frost-creep. Furthermore pedogenesis of cold-humid type such as gleyzation or peseudo-gleyzation also might af-fect the kanweoldo Deposit in the priod of severe cold-humid cli-mate of the Wrm. The Kanweoldo sediment and organic remnant(16,708 B.P. with error limit of 250 years) affected by severe cryogenic activities sug-gest that the paleoclimate of Late Wrm in Korea might be so cold and humid as to engender the cryogenic structure in subaerial silty and sandy silt deposits.

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중추유형발생기에 근거한 뇌졸중 환자의 치료적 접근 (Therapeutic Approach for Stroke Patients based on Central Pattern Generator)

  • 김중휘;김중선
    • The Journal of Korean Physical Therapy
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    • 제14권4호
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    • pp.131-146
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    • 2002
  • In the last years, it has become possible to regain some locomotor activity in patients with incomplete spinal cord injury (SCI) through intense training on a treadmill. The ideas behind this approach owe much to insights derived from animal studies. Many studies showed that cats with complete spinal cord transection(spinalized animals) can recover locomotor function. These observations were at the basis of the concept of the central pattern generator located at spinal level. The neural system responsible for the locomotor restoration in both cats and humans is thought to be located at spinal level and is referred to as the central pattern generator(CPG). The evidence for such a spinal CPG in human is emphasis on some recent developments which support the view that there is a human spinal CPG for locomotion. An important element in afferent inputs for both spinal injured cats and humans is the provision of adequate sensory input related locomotor, which can possibly activate and/or regulate the spinal locomotor circuitry This review article deals with the afferent control of the central pattern generator. Furthermore, the application of adequate afferent inputs related locomotor for stroke patients will be able to facilitate locomotion ability, which is automatic, cyclic, rhythmic. These insights can possibly contribute to a better therapeutic approach for the rehabilitation of gait in patients with stroke.

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THE GOVERNANCE OF RETIREMENT FUNDS IN MEMBERS RIGHTS AND TRUSTEES DUTIES IN SOUTH AFRICA: A LESSON LEARNT FROM USA, UK AND MALAWI

  • Nevondwe, Lufuno;Odeku, Kola;Matotoka, Mothlatlego
    • 동아시아경상학회지
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    • 제1권3호
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    • pp.55-70
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    • 2013
  • Purpose: The article looks at the member' rights and trustees duties and determines where should the emphasis be as it often happens that these two aspects often clash. Research Design, Data and Methodology: It is determined in this article whether the trustees owe fiduciary duties to both the fund and members and further determines whether the trustees should advance the interests of the members. Results: The article further looks at the governance of the retirement funds and argues that the proper governance of these funds protects the interest of the members. The duty to disclosure of information to members is of paramount importance to ensure that members are able to make well informed decisions. Conclusion: The article considers the issues of disclosure of information from other countries, United Kingdom, United States and Malawi. It is argued in this article that trustees must be persons who are trustworthy and have the best interest of the members at heart and must therefore familiarize themselves with the laws that regulate their duties.