• Title/Summary/Keyword: Secondary Sources

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A Numerical Study of the Fluid Flow and Heat Transfer Characteristics of the Two-Dimensional Turbulent Impingement Jet with a Confinement Plate (제한면을 가지는 이차원 난류 충돌젯트의 유동 및 열전달 특성의 수치적 연구)

  • 강동진;오원태
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.7
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    • pp.1675-1683
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    • 1995
  • A numerical study of the fluid flow and heat transfer characteristics of the two-dimensional impingement jet with a confinement plate has been carried out. The fluid flow was calculated by solving the full Navier-Stokes equation. In doing that, the well known SIMPLER algorithm was used and the trouble making convection term was discretized according to QUICKER scheme. The energy equation was simply solved by using the SOR method. For the Reynolds number of 10000, two channel heights, say 1.5 and 3.0 times the jet exit width, and two thermal boundary conditions constant wall temperature and constant wall heat flux were considered. Discrete heat sources were flush mounted along the impingement plate at a distance of 0, 2, 3, 4, 5, 6, 10, 12, times the jet exit width from the stagnation point. The length of each heat source is 4 times the jet exit width long. The Nusselt number averaged over each heat source was compared with experiment. Comparison shows that both calculations and experiment have the secondary peak of Nusselt number at downstream of stagnation point, even though there is a little quantitative difference in between. The difference is believed due to abscure thermal boundary condition in experiment and also accuracy of turbulence model used. The secondary peak is shown to be caused by rigorous turbulent flow motion generated as the wall jet flow is retarded and developes into the channel flow without flow reversal.

Trends in Research on Communication and Media in Indonesia: The Micro Meta-Analysis on Perspective, Theory, and Methodology

  • Bajari, Atwar
    • Asian Journal for Public Opinion Research
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    • v.5 no.1
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    • pp.41-62
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    • 2017
  • The political reformation in Indonesia is a determinant factor of the change in political communications and the roles of media. Currently, the political elites need media support, since it contextually has a significant role. Whoever has a good relationship with the media, will be loved by the public. On the other hand, the media also have a vested interest in the elite in running businesses and building the power of industry. Policies and capital pose a challenge to maintaining the continuity of the media. Independence and control of media are at stake, when the interests of the media and the elite collaborate with each other and then build a benefit on both sides. Meanwhile, the role of social media also cannot be neglected. The Indonesian political communication system is characterized by the presence of social media in a pseudo-relationship between the elite and the public. This paper tries to explain the growing trends of research in the academic environment and the research trends in political practice in Indonesia after the occurrence of post-reformation era in legislative and executive elections. The method used is the meta-analysis of research outcomes of university (dissertations) and secondary data sources. Data processing is done by meta-analysis of secondary data. The results of meta-analysis research indicate that, the objective conditions, in Indonesia, especially the political conditions, stimulate new spaces in communication research. The study of political communication becomes dominant in the academic environment. In addition, communication research is also characterized by a shift from the linear perspective (positivistic paradigm) to the interactive perspective (naturalistic paradigm). On the other hand, the development of politic and governance situations in Indonesia has prompted the establishment of polling agencies that help citizens understand the maps of political power and candidates in general elections and regional head elections.

Epidemiologic Investigation of an Outbreak of Shigella sonnei among Students in Bonghwa, 1999 (1999년 봉화군 일개 중.고등학교에서 발생한 세균성이질에 관한 역학조사)

  • Bae, Geun-Ryang;Lim, Hyun-Sul
    • Journal of Preventive Medicine and Public Health
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    • v.33 no.1
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    • pp.10-16
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    • 2000
  • Objectives : This study was carried out to investigate the sources of infection and modes of transmission of an outbreak of shigellosis that occurred among students of B middle and high school in Bonghwa, Korea from May 1 to 21, 1999. Methods : We conducted questionnaires to 468 students, 38 stalls and 9 food handlers twice times (May 6, May 21) for follow up and secondary attack rate. Personal details and history of illness and exposure to particular foods were sought. And we conducted rectal swab for culture to 243 students, 33 staffs and 9 food handlers. Bacteriological examinations of water in the school were done. Cases were identified as subjects who had diarrhea (two or more loose stools in a 24-hour periods) on or after May 1. Results : A total of 307 cases (attack rate: 59.6%) of 515 subject were identified, including 50 confirmed (46 students and 4 staffs) by S. sonnei. All 9 food handlers denied illness and were had rectal swab for culture at May 6 that were negative for S. sonnei. 146 of 307 reported fever, 156 had tenesmus, 44 reported vomiting, and only 5 of 307 reported blood in the stool. The median duration of diarrhea was 4 days (range: 1-18 days). The mean incubation period until onset of diarrhea was 63 hours (range: 46-144 hours) and the secondary attack rate was 2.8% (43 cases of 1,561 family members). Risk for illness was higher among students who had eaten watered kimchi at March 30 than among those who did not [301(72.7%) of 417 versus 5(9.6%) of 52; RR=7.51;95% CI=3.26-17.31]. Conclusion : The source of infection was estimated to be contaminated watered kimchi by ore or two food hardier who is presumed to be carrier.

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Electrochemical Simulation for Limited-Discharge Current Prediction of Li-ion Secondary Cell Using High-Rate Discharge (고율 방전용 리튬 전지의 한계 방전 전류 예측을 위한 전기화학 시뮬레이션)

  • Kim, Simon;Lee, Young Shin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.39 no.8
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    • pp.807-812
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    • 2015
  • Li-ion batteries are energy sources that are widely used in applications such as notebooks, cellular phones, power tools, and vehicles. They are devices in which stored chemical energy is changed to electrical energy by electrochemical reactions. They have a high energy density, small size, and are lightweight. In particular, power tools and vehicles require high charge/discharge rates. Therefore, in this paper, we perform electrochemical simulations using a commercial finite-element analysis program to determine the high discharge-rate characteristics of Li-ion cells. In addition, by performing high discharge-rate simulations, we found that the limited discharge current was 63 A. Based on the results obtained, we investigate the behavior of Li-ion cells with a high rate of discharge.

A Comparative Analysis on Educational Achievement in Mathematics Classifying by Content Areas of the Primary and Secondary School Students (초.중.고등학생의 수학과 내용 영역별 학업성취도 비교 분석 -2003~2008년 국가수준 학업성취도 평가 결과를 중심으로-)

  • Lee, Bong-Ju
    • Journal for History of Mathematics
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    • v.23 no.4
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    • pp.59-82
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    • 2010
  • The Purpose of this study is to draw a few lessons for the effective teaching and learning throughout a comparative analysis on the results of the educational achievement on Mathematics of the primary and secondary school students. The primary sources for this research are based on the results of the six-times national level tests performed annually by all level students from 2003 to 2008. In order to achieve this goal, I, firstly, extract the lowest content area in terms of the annual average of the right answer ratio after examining the ratio of right answers to each math problem by classifying all multiple-choice questions of the educational achievement tests from 2003 to 2008 into the relevant content areas. Next, the characteristics of the content area which distinguish the lowest right answer ratio are qualitatively analyzed. Lastly, information on the content area which the school students of all classes feel very difficult to solve is provided via reckoning the average right answer ratio per each content area against all math questions at the last six-times of the national level tests.

An Implementation of Integrated System for Topographic and Cadastral Data (지형 및 지적자료의 통합체계 구축)

  • 유복모;김갑진
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.18 no.2
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    • pp.143-155
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    • 2000
  • With the increasing needs for the integrated use of topographic and cadastral data in order to build an efficient geo-spatial information system. it is urgently necessary to research into its solution. The intention of this study is to detect error types of data and to propose adjustment methods for solving the problems caused by integrating topographic and cadastral data. For this purpose a primary integrated data model is created to link attribute data(land management system) and graphic data within cadastral information in the first step. In next, a secondary integrated data model based on the improved method is formed to coincide the graphic data of cadastral map with that of topographic map. At the first, because a numerous error types md sources caused by separate management of graphic and attribute data are easily checked, it is possible to suggest an improved method to correct these errors using the primary integrated data model. In addition, the accuracy in position and area with coordinate transformation method based on multi-block adjustment is more efficient than rubber-sheeting method. As a result, the secondary integrated data model could be built by harmonizing cadastral map with topographic map using the improved solution.

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CATALOGUE OF METEOR SHOWERS AND STORMS IN KOREAN HISTORY (한국 역사서 속의 별똥비와 별똥 소나기의 목록)

  • Ahn, Sang-Hyeon
    • Journal of Astronomy and Space Sciences
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    • v.21 no.1
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    • pp.39-72
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    • 2004
  • We present a more complete and accurate catalogue of astronomical records far meteor showers and meteor storms appeared in primary official Korean history books, such as Samguk-sagi, Koryo-sa, Seungjeongwon-ilgi, and Chosen-Wangjo-Sillok. So far the catalogue made by Imoto and Hasegawa in 1958 has been widely used in the international astryonomical society. The catalogue is based on a report by Sekiguchi in 1917 that is mainly based on secondary history books. We observed that the catalogue has a number of errors in either dates or sources of the records. We have thoroughly checked the primary official history books, instead of the secondary ones, in order to make a corrected and extended catalogue. The catalogue contains 25 records of meteor storms, four records of intense meteor-showers, and five records of usual showers in Korean history. We also find that some of those records seem to correspond to some presently active meteor showers such as the Leonids, the Perseids, and the n -Aquarids-Orionids pair. However, a large number of those records do not correspond to suck present showers. This catalogue we obtained can be useful for various astrophysical studies in the future.

Research on application of the Variations of Internationally circulated Standard Korean Language Curriculum (국제 통용 한국어 표준 교육과정 변이형 적용 연구 -해외 중등학교의 제2외국어로서 한국어를 중심으로-)

  • Park, Jin-Uk;Lee, Su-Mi;Jang, Mi-Jeong
    • Journal of Korean language education
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    • v.29 no.1
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    • pp.25-52
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    • 2018
  • This study purposed to discuss and suggest how to apply the internationally circulated standard Korean language curriculum to the fields of education. For this purpose, principles of the curriculum development that use reference of criterions like setting the education goals and stages of the Korean as second foreign language at the Korean foreign secondary school with the cases were reviewed. Studies about the curriculums of Korean language as an unit of state were began at 2010 and being continued in 2017. These researches pointed out a standard of the Korean language education, which influenced the development of curriculums, evaluations, and textbooks. Korean language teachers need lots of informations how to adjust the curriculums because they recognize that the curriculum as a reference of criteria is very difficult to be utilized. Roles of the reference of criteria that were extracted from the review on the curriculum development of the Korean as a second foreign language are providing a content basis for setting the goals of the curriculum and setting the stages connected with the operation of semesters. After the macroscopic development, plans for the phase of a syllabus run along. At this stage, sources of the items of education should be offered and elaboration of the education contents may design the syllabus. Finally, through a series of process, programs for Korean language education and textbook will be completed. Through this whole process, standard curriculum provides orientation and guidelines for the process of the development.

Analysis of a 6th Industrialization Model in the Saemangeum Grain Complex (새만금 복합곡물단지의 6차산업화 모델 분석)

  • Kim, Yooan;Jung, Chanhoon;Kim, Solhee;Kim, Chanwoo;Suh, Kyo
    • Journal of Korean Society of Rural Planning
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    • v.25 no.2
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    • pp.63-74
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    • 2019
  • As the awareness of food security has increased, the Korean government has established national projects, such as Saemangeum proclaimed land, to secure sources of grain. Saemangeum is a large-scale agricultural area that was constructed to maintain preparedness for unstable food markets. This study aims to develop a $6^{th}$ Industrialization Model (SIM) for Saemangeum Grain Complex by applying feasible strategies to wheat and two-rowed barley which have low self-sufficiency rates. In addition, this study estimates the potential economic value of each development strategy associated with a sixth industrialization model to create higher added values from production, processing and tourism experiences. The strategic plan for primary, secondary, and tertiary industries is to combine cultivating and processing wheat and two-rowed barley for sales and linking them to tourism experience. This study shows value added from the combination of the primary, secondary and tertiary industry of wheat and two-rowed barley are 7.5 and 23.0 times more than those of the primary and tertiary industry combination, respectively. Through branding Saemangeum Grain Complex's products, such as Saemanguem bread and craft beer, would further enhance the economic benefits derived from the complex.

Women's Body Exposure in Leisure Wear during the 1930s -Focused on Bathing Suits, Shorts, and Halters-

  • Lee, Yhe-Young;Farrell-Beck, Jane
    • Journal of the Korean Society of Clothing and Textiles
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    • v.36 no.6
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    • pp.592-600
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    • 2012
  • Social reactions to body exposure in American leisure wear (bathing suits, shorts, and halters) in the 1930s were analyzed to provide an understanding of the process of adopting more abbreviated and less-occasion specific styles of garments in women's fashion. The research questions were as follow: How did women expose their bodies in leisure wear during the 1930s? How did the social reaction to women's body exposure in leisure wear change throughout the 1930s? How did the body exposure in women's leisure wear play a significant role in the history of women's fashion? Primary sources were collected from issues of The New York Times published in the 1930s. Topics including dress, fashion, ethics, social ethics, and sexual ethics, were reviewed in The New York Times indices. The findings were analyzed and interpreted with reference to secondary sources that included books and research papers. The results showed that the body exposure of the styles as well as the place where these styles were worn was a public issue. Women were criticized and regulated for body exposure as well as for wearing bathing suits, shorts, and halters on the streets. However, the social regulations that restricted bathing suit styles almost disappeared by the end of the decade. This represented the change of social expectations toward body exposure in the 1930s. In addition, reports of laws that forbade the wearing of bathing suits, halters, and shorts outside of beaches, pools, and parks indicated women's increased attempts to expose their bodies in public places. However, reactions to women's body exposure in leisure wear changed to accept more flexibility in the social customs throughout the decade. These phenomena were a partial step toward the popularization of less occasion-specific styles - sportswear - that took place in the 20th century.