• Title/Summary/Keyword: 리치

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A study on design and aerodynamic characteristics of a spiral-type wind turbine blade (스파이럴형 풍력터빈 블레이드의 설계 및 공력특성에 관한 연구)

  • Lu, Qian;Li, Qiang;Kim, Yoon-Kee;Kim, Kyung-Chun
    • Journal of the Korean Society of Visualization
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    • v.10 no.1
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    • pp.27-33
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    • 2012
  • This paper describes a new design of small-scale horizontal wind blade, called spiral wind turbine blade. Theoretical and numerical approaches on the prediction of aerodynamic performance of the blade have been conducted. A theoretical equation is successfully derived using the angular momentum equation to predict aerodynamic characteristics according to the design shape parameters of spiral blade. To be compared with the theoretical value, a numerical simulation using ANSYS CFX v12.1 is performed on the same design with the theoretical one. Large scale tip vortex is captured and graphically presented in this paper. The TSR-$C_p$ diagram shows a typical parabolic relation in which the maximum efficiency of the blade approximately 25% exists at TSR=2.5. The numerical simulation agrees well with that of the theoretical result except at the low rotational speed region of 0~20 rad/s.

Flow Characteristics around Archimedes Wind Turbine according to the Change of Angle of Attack (받음각 변화에 따른 아르키메데스 풍력발전 날개 주위의 유동장 변화)

  • Li, Qiang;Kim, Hyun Dong;Ji, Ho Seong;Kim, Kyung Chun
    • Journal of the Korean Society of Visualization
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    • v.11 no.1
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    • pp.28-33
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    • 2013
  • This paper describes aerodynamic characteristics of an Archimedes spiral wind turbine with various angles of attack. The range of angles was controlled from $-30^{\circ}$ (clockwise) to $+30^{\circ}$ (clockwise). The rotating speed of wind turbine at the same angle of attack in both directions was different. The reason why the-maximum rotational speed was observed at $15^{\circ}$ in clockwise direction can be explained based on angular momentum conservation. Quantitative flow visualization around Archimedes wind turbine blade was carried out between $-15^{\circ}$ (clockwise) and $+15^{\circ}$ (counter clockwise) using high resolution PIV method. The relationship between drag force and rotating speeds was discussed. From these results, optimum design on yawing system of Archimedes spiral wind turbine may provide high efficiency on small wind power system.

A Hybrid Mobile Broadcasting Platform Based on HTML5 (HTML5 기반 융합 모바일방송 플랫폼)

  • Kim, Hyun-Soon;Kim, Sang-Hun;Kyung, Il-Soo;Chung, Shin-Il
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.11a
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    • pp.70-73
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    • 2011
  • 2005년 12월 1일 DMB(Digital Multimedia Broadcasting) 본 방송이 실시된 이후 다양한 형태의 방송, 통신 융합 서비스가 시도되었다. 그러나 DMB가 성공적으로 시장에 정착하였음에도 불구하고 방송사 등 시장 참여자들의 수익 창출의 어려움, 속도 및 요금 측면에서의 양방향 망의 한계, 방송사, 통신사의 시스템 및 망에 종속적이며 폐쇄적인 콘텐츠 제작 및 제공 방식 등으로 인하여 성공을 거두지 못하였다. 그러나 스마트 폰과 같은 모바일 스마트 디바이스의 성공으로 방송, 통신 서비스 시장에 새로운 전기가 마련되어 다양한 융합 서비스가 시도될 것으로 예상되며, 지상파 DMB가 이러한 다양한 서비스와의 경쟁에서 우위를 점하고 중심 매체로 자리잡기 위해서는 새로운 개념의 융합 서비스 플랫폼이 필요하다. 이에 본 논문에서는 이러한 새로운 개념의 플랫폼인 'HTML5 기반 융합 모바일방송 플랫폼'을 제안하고 실제 구현 예를 통하여 그 가능성을 제시하고자 한다. 제안하는 플랫폼은 누구나 콘텐츠 제공에 참여할 수 있고, 다양한 망, 단말, 서비스 모델이 융합되며, 표준화되고 개방된 API(Application Programming Interface)를 통하여 이를 소비할 수 있도록 하는 개념으로, 방송 콘텐츠 및 이에 의해 파생된 다양한 리치 미디어 콘텐츠의 생성, 전달, 소비에 이르는 생태계 전반에 대한 것이다. 이러한 플랫폼의 가능성을 제시하기 위하여 KBS(Korean Broadcasting System)는 서비스 시스템, 수신 프로그램 개발, 시험 서비스 구현 등의 개발을 진행하고 있으며, 그 결과를 본 논문에서 소개하고자 한다.

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MIWF: Message Inter-Working Framework to Connect Rich Communication Service Messages and SMS Messages (MIWF: 리치 커뮤니케이션 서비스 메시지와 단문메시지의 연동을 위한 메시지 연동 프레임워크)

  • Lee, Dongcheul
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.5
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    • pp.93-99
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    • 2013
  • We have used SMS to exchange messages between mobile phones. Since the network evolved to the ALL-IP network, the next generation messaging service, RCS, has emerged to the market. Because SMS and RCS coexist, we need to inter-work the messages between SMS users and RCS users. This paper introduces a message inter-working framework(MIWF) that can inter-work SMS and RCS without changing end user's UX. It defines the call flows between the network equipment and MIWF. Also, it shows how MIWF converts messages between 3 protocols. Performance evaluation proves that MIWF does not add loads to the existing network.

A Study of Renissasnce Decorative Detail -After 1995 Fashion Trend- (현대 패션에 나타난 르네상스적 장식요소에 관한 연구-1995년 이후에 나타난 트랜드 중에서-)

  • Lee, Eun-Young;Seong, Eun-Joo;Lee, Gi-Won
    • The Journal of Natural Sciences
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    • v.10 no.1
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    • pp.153-174
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    • 1998
  • It is based on variety imagination not in monotonous through after '95 fashion trend. Specially, in women's fashion coming back of the feminity with giving status and social advance. Renaissance fashion trend in these days trend. Among modern trend. We find decorative beauty in contemporary fashion trend. There are many expressions about deep and rich color and velvet material, exaggerated collar in ruff collar shape, and applied sleeves and stomacher

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A Study on the Architectural Characteristics of Drago Galić's Apartment Designs in Relation to Le Corbusier's Unité d'Habitation (크로아티아 건축가 드라고 갈리치의 집합주거의 건축특성과 유니테 다비타시옹과의 상관성에 관한 연구)

  • Yoon, Sunhee;Park, Jin-Ho;Baik, Seung Yeon
    • Journal of architectural history
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    • v.24 no.5
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    • pp.7-20
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    • 2015
  • Drago $Gali{\acute{c}}$ (1907-1992) has been acknowledged as one of most important modern Croatia architects of the 20th century and noted for his controversial apartment buildings at 35-35a and 43-43a blocks on Vukovar Street in Zagreb, Croatia. Although the two housings were highly regarded as the best examples of the post-war housing design in Croatia, a plagiarism controversy arose due to its similar exterior looks to Le Corbusier's $Unit{\acute{e}}$ d'Habitation in Marseille in 1952. This research intends to comparatively analyze architectural features implemented on the works of apartment of Drago $Gali{\acute{c}}$ and Le Corbusier's $Unit{\acute{e}}$ d'Habitation. The analysis focuses on architectural characteristics categorized in three parts: unit plan, community space, and unit combinations. The site survey was carried out to yield more useful information for the analysis. During this process, written and photographic documentations are collected for the further interpretation. In addition, scale drawings are reconstructed for the in-depth analysis of the project.

International Health Project for Improving the Level of Mother and Child Health in Developing Countries: Focusing on KOICA CTS Cases in Vietnam (개발도상국 모자보건 수준 향상을 위한 국제보건사업: 베트남 KOICA CTS 사례를 중심으로)

  • Choung, Yoo-Chan;Shin, Jae-wan
    • Journal of Appropriate Technology
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    • v.6 no.1
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    • pp.45-50
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    • 2020
  • We developed the world's first wireless ultrasound diagnostic device. For the smooth delivery of pregnant women, the WHO requires four prior examinations, and the use of ultrasound diagnostic devices is essential for this purpose. However, income levels and medical facilities in developing countries are falling short. We conducted KOICA's CTS program in Vietnam using a self-developed radio ultrasound diagnostic device. We supplied Sonon300C, a portable wireless ultrasound diagnostic device, to health centers and hospitals in Huong-Hoa district, Vietnam, and conducted an outreach program in an effort to further enhance business performance. As a result, the rate of ultrasound diagnostics in the region reached 100% and the percentage of trained graduates increased to 59%.

Effect of Oligonol, a Low Molecular Weight Polyphenol Derived from Lychee on Oxidative Stress-Related Hepatic Damage in Streptozotocin-Induced Diabetic Rats (리치 저분자 폴리페놀인 Oligonol의 Streptozotocin 투여 당뇨 쥐에서 산화적 스트레스와 관련된 간 손상에 미치는 영향)

  • Noh, Jeong Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.4
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    • pp.475-482
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    • 2015
  • This study was conducted to examine whether or not oligonol, a low molecular weight polyphenol derived from lychee fruit, has an ameliorative effect on diabetes-induced oxidative stress-related hepatic damage in streptozotocin (STZ)-induced diabetic rats. Oligonol (10 or 20 mg/kg body weight; O10 or O20, respectively) was orally administered every day for 10 days to STZ-induced diabetic rats, and its effects were compared to vehicle-treated diabetic (Veh) and non-diabetic rats. Administration of 20 mg/kg of oligonol significantly decreased liver weight compared with the Veh group (P<0.05). Elevated levels of hepatic glucose, reactive oxygen species, peroxynitrite, and lipid peroxidation were detected in diabetic vehicle rats, whereas oligonol treatment significantly attenuated these levels (P<0.05). In diabetic vehicle rats, hepatic antioxidant enzyme protein levels decreased, whereas oligonol treatment showed significant elevated results. For inflammation-related protein expression, oligonol-treated groups showed insignificant reduction. Oligonol improved expression of proapoptotic protein caspase-3 in the liver of diabetic rats (P<0.05). In conclusion, these results provide important evidence that oligonol exhibits an inhibitory effect on oxidative stress and apoptosis-related protein expression as well as a hepato-protective effect against the development of diabetic complications in STZ-induced type 1 diabetic rats.

Strategies for the Services for Immigrant Population in Public Libraries (공공도서관의 이주민서비스 전략 연구)

  • Lee, Yeon-Ok;Chang, Durk-Hyun
    • Journal of Korean Library and Information Science Society
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    • v.44 no.1
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    • pp.357-384
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    • 2013
  • "The IFLA Multicultural Library Manifesto" affirms that libraries should serve all members of the community without discrimination based on cultural and linguistic heritage; provide information in appropriate languages and scripts; and, give access to a broad range of materials and services reflecting all communities and needs. Public libraries in Korea currently are facing the challenge to adopt this IFLA manifesto as Korea is rapidly changing toward a multicultural society. In regard to these speculations, this study explores the experiences and major characteristics of public library services for multicultural population in Richmond, Canada. Based on the case study, this paper scrutinizes the current situation of public library services for multicultural immigrant population in Busan area, and develops several service agenda as they can be oriented to the new strategic plans of public libraries in Korea.

A Study of consumer's behavior and classifications by advertising techniques of mobile character (모바일 캐릭터의 광고기법에 따른 타켓별 유형분류와 소비자 반응 연구)

  • 강대인;주효정
    • Archives of design research
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    • v.17 no.2
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    • pp.393-402
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    • 2004
  • The mobile advertisement has varied on lifestyle of people, who live aninformation-oriented society with portable equipment such as web phone and PDA(Personal Digital Assistant). Also, the advertising has expended mobile techniques and its application field unpredictably. The intrinsic characteristic of misdistribution, reach, and convenience in mobile advertisement add up the capacity of a location, information and individualize. This market condition leads the basic audio focused formal mobile advertisement to the new mobile Internet environment with an additional able of data communication. Moreover, the type of SMS (Short Message Service), Graphic, Wep Push, and ridchmedia, which based on music, basic graphic, voice, and letters transfer by mobile terminal and the mobile character is present inevitably correlation with pixel art and animation in 2D(Two Dimensions) techniques. Thus, this research appoints the importance and its role of mobile advertisement that is core of the business marketing in new media era. To activate mobile market, the mobile companies classify the characteristic of consumers with developed commercial use of mobile character and research their behavior to meet optimal mobile character in business.

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