• Title/Summary/Keyword: 현대사회

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Attrition and Heat Transfer Characteristics of Fluidized Bed Materials for a Solar Hybrid Process (태양열 하이브리드 공정을 위한 유동층 입자들의 마모 및 열전달 특성 연구)

  • Kim, Hyung Woo;Lee, Doyeon;Nam, Hyungseok;Hong, Young Wan;Seo, Su Been;Go, Eun Sol;Kang, Seo Yeong;Lee, See Hoon
    • Clean Technology
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    • v.26 no.1
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    • pp.65-71
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    • 2020
  • Various solar hybrid energy conversion processes, which have both the advantages of renewable energy sources and fossil energy sources, have been developed in the world because stable and predictable energy supplies, such as electricity and natural gas, are necessary for modern societies. In particular, a solar hybrid energy conversion process based on a dual fluidized bed process concept has been expected as the promising solution for sustainable energy supply via thermochemical conversions, such as pyrolysis, combustion, gasification, and so on, because solar thermal energy could be captured and stored in fluidized bed materials. Therefore, the attrition and heat transfer characteristics of silicon carbide and alumina particles used for fluidized bed materials for the solar hybrid energy conversion process were studied in an ASTM D5757 reactor and a bubbling fluidized bed reactor with 0.14m diameter and 2m height. These characteristics of novel fluidized bed materials were compared with those of sand particles which have widely been used as a fluidized bed material in various commercial fluidized bed reactors. The attrition resistances of silicon carbide and alumina particles were higher than those of sand particles while the average values of heat transfer coefficient in the bubbling fluidized bed reactor were in the range of 125 ~ 152 W m-2K-1.

Practitioners' Perception of Landscape Education in Universities (대학 조경교육에 대한 현장 실무자 인식 조사)

  • Joo, Shin-Ha
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.3
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    • pp.13-24
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    • 2014
  • This study investigates the practitioners' perception of Landscape Education in the universities in order to satisfy the demands of the rapidly changing industry. The survey was conducted for 257 practitioners to analyze the overall perception of Landscape Education, the importance and utilization of each course in universities, and the importance and utilization of each landscape process step. The overall perception of Landscape Education was slightly negative, and more practical education was demanded to improve the students' adaptability on the job. Practitioners suggested that universities should teach more practical expertise and related fields. They re-educated deficient aspects such as practical skills, computer techniques and legislational knowledge through the new employee training. The survey also showed that professors should be most responsible for a better education; however, students and practitioners have to endeavor together. According to the findings, planting design, landscape design, landscape materials, landscape planning and landscape construction as well as management were important. They are also considered as practical courses. However, practitioners perceived that university education was not sufficient for the constructional process. This means that Landscape Education in the universities has been more focused on planning and design. Because the universities are essentially for the research and study, changing the curriculum as practitioners suggested is not necessary. Nevertheless, it suggests for more practical education and balanced curriculum including construction and management that should be seriously considered. This study was focused on the practitioners' perception. Many of the respondents were from Seoul metropolitan area, therefore, it's hard to generalize the findings. A further study should be considered that would include instructors as well as students.

Representation of East Asia in US World Geography Textbooks: Focused on China and Japan (미국 세계지리 교과서에 재현된 동아시아 - 중국과 일본을 중심으로 -)

  • Sung, Sin-Je
    • Journal of the Korean Geographical Society
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    • v.47 no.2
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    • pp.297-309
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    • 2012
  • This study examines how East Asia is represented in US World Geography textbooks and what kind of cultural and political epistemological frameworks are embedded in those representation focused on China and Japan. For this, four World Geography textbooks that widely used in public middle school throughout the State of Connecticut are selected as the major units of analysis and analyzed using content analysis. The results are as follows. First, The textbooks have the cultural epistemological framework that East Asia are portrayed not only as homegenous and static world but also as exotic world whose mode of life is quite different from that the West. Second, China are represented as having more traditional and negative images, whereas Japan are portrayed as receiving more modern and positive images in the textbooks. This difference is caused by the relationship between the U.S. and them and imply that the epistemological framework on East Asia of American can change according to the relationship between the U.S. and East Asia. Third, the textbooks seem to be dominated by colonialism epistemological framework that emphasize hierarchical order between the U.S. and East Asia and omit East Asian countries' contribution to global cultures and economies as political epistemological framework. These findings suggest the need to investigate the epistemological frameworks underlying World Geography textbooks used Korean classroom about neighbor Asia or non-Western societies.

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Vehicle Emergency Lamp Fuzzy Control Systems Using The GPS (GPS를 이용한 자동차 비상등 작동 장치)

  • Kwon, Yunjung;Nam, Sangyep
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.6
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    • pp.276-281
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    • 2014
  • Necessities of a traffic means work a car in the modern society human to an usability of a life is enjoying. On the other hand, the damage by traffic accident increment the human quotient worked as we were in proportion to the vehicle which increased. Passing an examination moves necessarily on an obstacle to suddenly appear at the fronts if a car travels and the vehicles which stopped suddenly. Dynamic passing an examination about an obstacle turn on Vehicle Emergency Lamp to by hand when is unhurried, and can turn off, but to appear urgently dynamic passing an examination in time human is instinctive, but cannot inform an emergency to a back vehicle, and a rear-end collision occurs. A car we synthesize a speed of a vehicle, and this unit analyzes as we use GPS, and to drive runs Vehicle Emergency Lamp to automatic in the situations that shall turn on emergencies etc. If a speed of a vehicle continuously slows down in too high-speed driving or low-speed driving, or we are stopped, Vehicle Emergency Lamp is always turned on. It was built if we rise again as clearing itself from risk, and a speed of a vehicle judges, and we turn off Vehicle Emergency Lamp to automatic. It runs till rear-end collision sensor operates, and by hand reset does Vehicle Emergency Lamp a driving vehicle collides from behind to a back vehicle or when a driving vehicle was overthrown. It is shortened very much to the chain rear-end collision traffic accident that is a traffic accident of large size if we use this unit. And we did authentication through the experiment which a driver was helpful to unnecessary operation and a relaxed safe driving during drivings.

SCANNING ELECTRON MICROSCOPIC STUDY OF THE EFFECT OF ACIDIC DRINK ON ENAMEL EROSION : A CASE REPORT (탄산음료에 의해 부식된 법랑질 표면변화에 대한 증례발표)

  • Kim, Su-Youn;Park, Jae-Hong;Kim, Gwang-Chul;Choi, Young-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.35 no.3
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    • pp.509-515
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    • 2008
  • It is widely believed that the increase in the prevalence of dental erosion is due to soft drinks. The purpose of this study was to assess the influence of soft drinks and etchant on the erosion of tooth enamel and the effect of tooth brushing on the abrasion of eroded enamel, and the effect of milk, saliva and Tooth $Mousse^{(R)}$ on the remineralization. The changes in tooth enamel surface were observed by scanning electron microscophy. The results were as follows; 1. The pH of Coca-Cola and Chilsung-Cider were higher than the pH of FineEtch 37 and $Tyrian^{TM}SPE$. 2. The SEM photos revealed that the pattern of the surface eroded by Coca-Cola and Chilsung-Cider were more obvious than that eroded by etchants. 3. The results of remineralization by saliva, milk, Tooth $Mousse^{(R)}$ were not different from each other. 4. The remineralization by saliva decreased tooth brushing abrasion.

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A Case of the competencies-based mathematics lessons of one French foreign school (핵심역량 제고를 위한 수학 수업 사례 고찰 - 한국내 프랑스 외국인학교를 중심으로 -)

  • Choe, Seung-Hyun;Hwang, Hye-Jeang
    • Journal of the Korean School Mathematics Society
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    • v.15 no.1
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    • pp.81-108
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    • 2012
  • One of the keyword in every nation's recent educational policy is key competencies. Considering national competitiveness originating from educational competitiveness, educational policy has been driven to identify key competencies and realize them through school education. Within this context some countries have developed competencies-based curriculum and discussed ways to relate key competencies and subject matter areas. However, there have been few researches on how to reflect or integrate key competencies into subject matter areas. Because of this reason, the ways to incorporate and integrate key competencies into three subject areas including mathematics were investigated. The recent trends of curriculum, teaching and learning, and assessment of domestic and foreign cases were explored by the subject of one Korean international middle school, one British foreign school in Seoul, one French foreign school in Seoul, and four middle schools in New Zealand. To establish competencies-based school education, there should be intimate connection system among curriculum, teaching and learning, assessment, and teacher education. Through analysis of domestic and foreign cases, some conclusions regarding how these aspects have changed with the emphasis of key competencies were drawn. In this paper, through classroom observation and teacher interview, a case of the competencies-based mathematics lessons of one French foreign school was investigated. As a result, summaries and recommendations related to ways to improve subject teaching and teacher education in light of key competencies were presented. In these recommendations, the ways to reconstruct subject-based curriculum, the content-specific teaching and learning, and educational assessment were included.

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Practical Study for Developing Graphic Design Adopting Systematic Theories of Typography (타이포그래피의 체계적 이론을 활용한 그래픽디자인의 실무적 발전 방안)

  • Lee, Ki-Bok;Hong, Young-Il
    • The Journal of the Korea Contents Association
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    • v.10 no.11
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    • pp.80-91
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    • 2010
  • Typography is very important for the delivery of information and for its aesthetic functions, typography focuses on facilitating faster and easier legibility for audience in modern society. But analysis for pre-studies for typography are limited in trend in the center of Kinetic Typography, dissolution of typography and territory extend as well as its typography analyzed by plastic arts aspects to acutely requiring expressing strategy and study based on typographic theory in working-level are insufficient. This study is to apply systematic theory to typography in order to suggest guidelines for increasing utility of typography for graphic design. It presents case studies, organized by theme, focusing on graphic design artworks featured in world-renowned specialty publications like the Creative 38 Annual Awards during 2008 and 2009. For practical help to designers engaged in various projects, it also suggests practical tactics for development that may enhance creative strategies in the creation of designs adopting typography. This study offers systematic usage methods of typography to the practical graphic designers and expected to contribute to the development of graphic designs that stimulate the visual senses of their audiences.

A Study on Korean Traditional Philosophy as the Service Economy Philosophy (서비스경제철학으로서의 한국고유사상 정합성연구)

  • Kim, Hyunsoo
    • Journal of Service Research and Studies
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    • v.7 no.3
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    • pp.105-118
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    • 2017
  • The current research investigates the basic philosophy that would serve as a foundation for the development of the service economy. In particular, the current work suggests that the Korean traditional philosophy fits the philosophy of the service economy because of the relational nature of the Eastern culture (vs. Western culture). Therefore, it is suggested that trough manifestation of the Korean traditional philosophy, the service economy would be invigorated. The yin-yang and the Two Taegeuk do not emphasize the role of human, and thus, a new philosophy incorporating this aspect needs closer attention. Therefore, the Korean traditional philosophy, structured in a Three Taegeuk framework could serve as the foundation for the development of the service economy. The Three Taegeuk framework relates to the harmonization, horizontality, bi-directionality, and relational aspects of the service industries. For example, human serving the agent role in the society resembles the current service economy where service workers and customers serve important roles in value creation. Taken together, the current research suggests that the Korean traditional philosophy serve as an important foundation for the development of the service economy.

Short-term Mortality Prediction of Recurrence Patients with ST-segment Elevation Myocardial Infarction (ST 분절 급상승 심근경색 환자들의 단기 재발 사망 예측)

  • Lim, Kwang-Hyeon;Ryu, Kwang-Sun;Park, Soo-Ho;Shon, Ho-Sun;Ryu, Keun-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.10
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    • pp.145-154
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    • 2012
  • Recently, the cardiovascular disease has increased by causes such as westernization dietary life, smoking, and obesity. In particular, the acute myocardial infarction (AMI) occupies 50% death rate in cardiovascular disease. Following this trend, the AMI has been carried out a research for discovery of risk factors based on national data. However, there is a lack of diagnosis minor suitable for Korean. The objective of this paper is to develop a classifier for short-term relapse mortality prediction of cardiovascular disease patient based on prognosis data which is supported by KAMIR(Korea Acute Myocardial Infarction). Through this study, we came to a conclusion that ANN is the most suitable method for predicting the short-term relapse mortality of patients who have ST-segment elevation myocardial infarction. Also, data set obtained by logistic regression analysis performed highly efficient performance than existing data set. So, it is expect to contribute to prognosis estimation through proper classification of high-risk patients.

Protective Effects of Black Soybean Seed Coat Extracts against Oxidative Stress-induced Neurotoxicity (산화적 손상에 의해 유도된 신경세포독성에 대한 검정콩 껍질 추출물의 보호효과)

  • Kwak, Ji Hyeon;Jo, Yu Na;Jeong, Ji Hee;Kim, Hyeon Ju;Jin, Su Il;Choi, Sung-Gil;Heo, Ho Jin
    • Korean Journal of Food Science and Technology
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    • v.45 no.2
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    • pp.257-261
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    • 2013
  • Rat pheochromocytoma cells (PC12) and mice were utilized as in vitro and in vivo models to determine the neuroprotective effects of a 70% acetone extract of black soybean seed coat (BSSCE). BSSCE showed higher total phenolic contents than other extracts. Intracellular reactive oxygen species accumulation from $H_2O_2$ treatment of PC12 cells was significantly reduced when BSSCE was present in the media compared to PC12 cells treated with $H_2O_2$ only. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromide (MTT) reduction assay and lactate dehydrogenase assay also showed significantly increased protective effects in PC12 cells. In addition, BSSCE improved the in vivo cognitive ability against amyloid beta peptide-induced neuronal deficits.