• Title/Summary/Keyword: sphere

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A Study on Duty Performance area of Fisheries & Shipping Business High School Teachers (수산.해운 전문계열 교사의 직무수행 영역에 관한 연구)

  • Kim, Sam-Kon;Cha, Cheol-Pyo;Ban, Gun-Woo
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.1
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    • pp.79-90
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    • 2010
  • This study referred to relevant literatures, collected professional advice, created the sphere of duty with considering the characteristics of marine products-marine transportation education and teachers' specialty, and researched the feasibility of duty sphere classified from 2nd of September in 2008 to 20th of October in 2008 by selecting 80 professional teachers at random teachers who were working in 4 schools that had local 1. As the result of this study, it is proper to classify the sphere of marine products-marine transportation professional teachers into teaching-learning sphere, actual training guidance sphere, life guidance sphere, class management sphere, administrative performance sphere, specialty extension sphere, academic-industrial cooperation and community connection sphere. 2. For the contents of each sphere of marine products-marine transportation teachers' duty, it is proper to systematize teaching-learning field with 32 contents of duty, actual training guidance field with 21 contents of duty, life guidance sphere with 18 contents of duty, class management sphere with 12 contents of duty, administrative performance sphere with 18 contents of duty, specialty extension sphere with 15 contents of duty, academic-industrial cooperation and community connection sphere with 9 contents of duty respectively.

Laminar Flow over Two Spheres in a Tandem Arrangement (직렬로 배열된 두 개의 구를 지나는 층류 유동)

  • Kim Dong-Joo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.5 s.248
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    • pp.480-488
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    • 2006
  • Numerical simulations of flow over two spheres placed in a tandem arrangement are conducted to investigate the effect of the inter-sphere spacing on the flow characteristics. The Reynolds numbers considered are 100, 250, 300 and 425, corresponding to steady axisymmetric, steady planar-symmetric, unsteady planar-symmetric, and unsteady asymmetric flows, respectively, in the case of a single sphere. For small inter-sphere spacings, the flow past two spheres is more stable than that past a single sphere. For example, with the spacing of the sphere radius, the flow is steady axisymmetric up to Re=300. However, for relatively large spacings, the flow past two spheres becomes unstable and vortex shedding takes place even at Re=250. The drag coefficient of the rear sphere decreases significantly with decreasing inter-sphere spacing due to reduction of the stagnation pressure, thus being smaller than that of the front sphere. Also, the rear sphere shows large fluctuations of the lift force as compared to the front one in the case of unsteady flow.

A Typology of Media-Public Sphere Relationships (공론장-미디어 관계의 유형화)

  • Cho, Hang-Je;Park, Hong-Won
    • Korean journal of communication and information
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    • v.50
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    • pp.5-28
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    • 2010
  • The theoretical scope of the public sphere has been dramatically expanded as a result of new academic inquiries into the nature of the political and the public in contemporary societies. While appreciating the value of the concept of the public sphere for understanding democratic roles of the media, scholars began to raise questions on Habermasians' exclusive focus on news and public affairs programs, arguing that various entertainment programs also can invoke political deliberation. Terms like affective public sphere, emotional public sphere, aesthetic public sphere, expressive public sphere were used to capture this new conception. To comprehend the theoretical and practical implications of the conceptual expansion of the public sphere for media studies, this study attempted to provide a typology of media-public sphere relationships. By using public-private and rational-emotional axes as two criteria for classification, we created four prototypes of the public sphere (i.e., political public sphere, populism, difference pluralism, and intimacy/privacy) and discussed the characteristics of each type. After setting out media communication as a form of meta-public sphere that mediates and coordinates the four different types of the public sphere, we presented public service broadcasting as an exemplar meta-public sphere in the contemporary society of multiple social antagonisms and differences.

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A Theoretical Approach of Social Ecological Model for School Health Promotion Program (학교 건강증진 사업을 위한 사회생태학적 모형의 이론적 접근)

  • Jung, Sang-Hyuk;Yoon, Hee-Sang
    • The Journal of Korean Society for School & Community Health Education
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    • v.7
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    • pp.87-99
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    • 2006
  • Objectives: This study is to draw the design of the program which is improve school health promotion participation by applying the Social Ecological Model based on the literature review on the health promotion. Methods: Literature review was carried out based on 5 factors of social ecological model using computer search engines of Google, ProQuest, and Riss4U. Results; Social Ecological Model is consist of individual, interpersonal, institutional/organizational, community, and policy. Individual sphere is drawn from Health Belief Model, interpersonal sphere is Social Support Theory, institutional/ organizational sphere is institutional resources theory, community sphere is community model, and policy sphere is Social Marketing Theory. The literature review show that the important variables affecting health promotion exist in each sphere. Individual sphere has social economic status, age, sex, sensitivity and specificity of illness, self-efficacy. Interpersonal sphere has support and use of family, friend and neighbor. Institutional/Organizational sphere has environment service reliability and utility. Conclusions: Community sphere has distance, neighborhood safety, interrelationship among institutions. Policy sphere has cost, legislation advertisement, lobby and concern and leadership of Institution.

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Experiments on Time Dependent Film Boiling on a Sphere

  • Ounpanich Bancha;Pomprapha Temsiri;Archakositt Urith;Nilsuwankosit Sunchai
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.403-406
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    • 2002
  • A number of the experiments on the phenomenon in which the thermal energy was transferred from a hot sphere to the surrounding water through the film boiling process had been conducted. As the sphere only carried the thermal energy associated with its initially high temperature but did not contain any other thermal source, the film boiling was only driven by the decreasing temperature of the sphere and, thus, was time dependent. The results from the experiments showed that the temperature of the sphere was slowly decreased in the beginning. This corresponded to the period in which the sphere was penetrating the water surface. Later, when the sphere was fully submerged and the transition film boiling was observed over the whole surface, the temperature of the sphere was decreased relatively much faster. In the last stage, the temperature of the sphere was again slowly decreased. This was considered caused by the relatively low temperature of the sphere, which reduced and later ceased the film boiling process. In addition, the estimation of the departure rate of the steam bubbles from the film layer was also correlated for the experiments.

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NOTES ON TANGENT SPHERE BUNDLES OF CONSTANT RADII

  • Park, Jeong-Hyeong;Sekigawa, Kouei
    • Journal of the Korean Mathematical Society
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    • v.46 no.6
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    • pp.1255-1265
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    • 2009
  • We show that the Riemannian geometry of a tangent sphere bundle of a Riemannian manifold (M, g) of constant radius $\gamma$ reduces essentially to the one of unit tangent sphere bundle of a Riemannian manifold equipped with the respective induced Sasaki metrics. Further, we provide some applications of this theorem on the $\eta$-Einstein tangent sphere bundles and certain related topics to the tangent sphere bundles.

Characteristics of Flow p ast an Oscillating Sphere (진동하는 구를 지 나는 유동의 특성)

  • Lee, Dae-Sung;Yoon, Hyun-Sik;Ha, Man-Yeong
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.284-287
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    • 2008
  • Flow over a sphere under forced oscillation at Re=300 is simulated for various frequency ratios which are defined as excitation frequency over natural frequency of stationary sphere. The results of oscillating sphere are compared with those of stationary sphere and an oscillating cylinder. Detailed vortical structures, hydrodynamic forces and frequencies of the wake are prescribed as a function of frequency ratio. For oscillating sphere, planar symmetry of the wake is kept and two nearly symmetric hair pin vortices are induced by oscillation for one period of oscillation when the frequency ratio is bigger than 0.5. Modulation phenomenon which can be found in an oscillating cylinder were not seen for an oscillating sphere.

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The Public Television Crisis and the Mutation of the Public Sphere in Neo-liberalism (신자유주의 시대 공영방송의 위기와 공공영역의 변화)

  • Lee, Sang-Hoon
    • Korean journal of communication and information
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    • v.57
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    • pp.250-266
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    • 2012
  • In neo-liberalism, the change-value of the market and of the machandise based on the individual as the consumer dominate the public sphere, and the capital power encroach on it. with the technological revolution. At the same time the public sphere as such represent the media sphere, which is more and more subordinate, and have no choice but to do to the governmental authority having political power privatized. The private usage of reason in the public sphere is carried out at the structual level. How can we call such a space in which the private usage of reason is generalized and dominant as the public sphere? And so now, we sound out the possibility of the public sphere such as a new space of the universality where the public usage of reason can be realized without any limits and with free. So, when we imagine the proletarian public sphere, in which co-exist the divers private interests, as a new public sphere capable to be constructed, we can address a question as follow. What is the caracteristic of the proletarian public sphere in modern society?, Is the public community able to be formed and realized in such space? How would have the proletarian public sphere the carateristics of the publis sphere? What is the attribute of the community that the proletarian public sphere would make, and what is its force of emancipation? The power is no longer stable and static. Rather, it is reconstructed and reorganized in the divers phases of the everyday life. It is the reason why we put on the order of the day the proletarian public sphere as alternative public space, which would be a place of divers hegemonic representation. And now, we are aware of the beginning of thses changes.

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Generation of a plane-wave field by point focusing of acoustic potential energy on the radiation sphere in the wavenumber domain (파수 영역의 방사 구면에서 음향 에너지 집중을 통한 평면파 생성 방법)

  • Chang, Ji-Ho;Kim, Yang-Hann
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.820-823
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    • 2007
  • In the wavenumber domain, each point on a radiation sphere indicates a plane wave of the frequency corresponding to radius of the sphere and the position on the sphere shows propagating direction of the plane wave. This concept is extended from the research by Choi[1] where he focus acoustic potential energy at a point on a radiation sphere. Here we propose the method to focus the energy at a point on the radiation sphere, as a result, we can easily generate a plane wave which propagates to any direction that we want.

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Numerical Study for Effects of Density-Stratification on Wake Behind a Sphere (구 후류에 미치는 유동장 밀도 성층화 영향 전산 해석)

  • Lee, Sung-Su;Yang, Kyung-Soo;Park, Chan-Wook
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.5
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    • pp.553-559
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    • 2004
  • Stratified flow past a three-dimensional obstacle such as a sphere has been a long-lasting subject of geophysical, environmental and engineering fluid dynamics. In order to investigate the effect of the stratification on the near wake, in particular, the unsteady vortex formation behind a sphere, numerical simulations of stratified flows past a sphere are conducted. The time-dependent Navier-Stokes equations are solved using a three-dimensional finite element method and a modified explicit time integration scheme. Laminar flow regime is considered, and linear stratification of density is assumed under Bossiness approximation. The computed results include the characteristics of the near wake and the unsteady vortex shedding. With a strong stratification, the separation on the sphere is suppressed and the wake structure behind the sphere becomes planar, resembling that behind a vertical cylinder.