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Real-Time 3-D Ultrasound Imaging Method using a 2-D Curved Array (이차원 곡면 어레이를 이용한 실시간 3차원 초음파 영상화 기법)

  • 김강식;한호산;송태경
    • Journal of Biomedical Engineering Research
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    • v.23 no.5
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    • pp.351-364
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    • 2002
  • Conventional 3D ultrasound imaging using mechanical ID arrays suffers from poor elevation resolution due to the limited depth-of-focus (DOF). On the other hand, 3D imaging systems using 2D phased arrays have a large number of active channels and hence require a very expensive and bulky beamforming hardware. To overcome these limitations, a new real-time volumetric imaging method using curved 2-D arrays is presented, in which a small subaperture, consisting of 256 elements, moves across the array surface to scan a volume of interest. For this purpose, a 2-D curved array is designed which consists of 90$\times$46 elements with 1.5λ inter-element spacing and has the same view angles along both the lateral and elevation directions as those of a commercial mechanical 1-D array. In the proposed method, transmit and receive subapertures are constructed by cutting the four corners of a rectangular aperture to obtain a required image qualify with a small number of active channels. In addition the receive subaperture size is increased by using a sparse array scheme that uses every other elements in both directions. To suppress the grating lobes elevated due to the increase in clement spacing, fold-over array scheme is adopted in transmit, which doubles the effective size of a transmit aperture in each direction. Computer simulation results show that the proposed method can provide almost the same and greatly improved resolutions in the lateral and elevation directions, respectively compared with the conventional 3D imaging with a mechanical 1-D array.

The study on the policy for the formation of the innovation cluster : Focus on Pangyo Technovalley in Gyeonggi-Province (혁신 클러스터 구축을 위한 정책방향 설정에 관한 연구 : 판교테크노밸리를 중심으로)

  • Im, Jongbin;Cho, Hyeongrye;Chung, Sunyang
    • Journal of Korea Technology Innovation Society
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    • v.15 no.3
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    • pp.675-699
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    • 2012
  • Recently innovation cluster has been emphasized as a valid policy measure for innovation. For suggesting a new model of innovation cluster, we conducted literature review for the theories of regional innovation system(RIS) and innovation clusters. As a result, the success factors of innovation cluster were classified into system measures, physical measures, and social(human resources) measures from the perspective of RIS. The case of Gyeonggi province's innovation cluster policy was examined for an empirical analysis. For an in-depth analysis, a survey for the tenant companies in Pangyo technovalley(PTV) was conducted. As a result, it was found that Gyeonggi province's innovation cluster policy is evolving from 'a government-initiated system' to 'the 3rd-generation convergence RIS' and that PTV is closely related to the system measures of 'support for up-to-date management and technology information' and 'support for academic-research-industry cooperative research and technological cooperation,' physical measures of 'strengthening the function of PTV support division' and 'shared research equipment and other infrastructures,' and social measures of 'legal, financial, and administrative support system' and 'public childcare facilities'. Also, technology sector was divided into IT and non-IT for a validity check to find out that there was no significant difference in all factors, except for the public relations factors. This study is expected to provide resources for other related researches.

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The Development of the Convergence Education Program based on the Creation of Scientific and Cultural Content (과학문화콘텐츠 구성을 기반으로 한 융합형 교육 프로그램의 개발 방안)

  • Cho, Nam-Min;Kim, So-Ryun;Son, Dal-Lim
    • The Journal of the Korea Contents Association
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    • v.15 no.1
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    • pp.506-518
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    • 2015
  • Recently there are growing needs and demand to enhance 'Unity of knowledge' as the concept of "Creating new value through integration and convergence" is developing rapidly in many different areas in the society. This also has significant implication to education. Especially, it requires paradigm shift in terms of required capabilities and qualifications for the students with science major. To accommodate this trend, Natural Sciences and Engineering's College has been increasing convergence education which focus on cultivating creative and cooperative learning capabilities as well as acquiring fundamental knowledge of individual majors. However, convergence education developed and implemented by Sciences college or liberal education so far has been mechanical combination of knowledge from different academic fields - not effectively integrated and interdisciplinary education. Given this situation, this research is to develop and propose a "convergence education program based on the development of scientific and cultural contents" as an education tool to enhance capabilities to apply and re-create integrated knowledge as well as acquire and learn existing knowledge. Education program developed in this research aims to achieve two different and sequential capabilities. First is to understand 'Science and Technology' and 'Cultural Archetype' which would be essential and useful to create cultural contents. Second is to develop capabilities to convert this understanding into cultural contents - a storytelling capability. This education program is differentiated in that it defines cultural contents as a medium to converge and integrate science and technology and humanities. By leveraging the concept of cultural content and storytelling, this education program would be able to overcome restrictions of existing interdisciplinary approach. Also, this program would encourage students to try in-depth research and new applications, and develop logical and creative thinking.

A Crisis in Public Broadcasting of South Korea A Perspective from the Case of the So-called "Paik Jong-moon's Taped Conversation" at MBC with a Focus on the Press Control by Political Power (MBC '백종문 녹취록' 사건으로 본 공영방송의 위기 정치권력의 언론 통제 기제를 중심으로)

  • Kim, Sang Gyoon
    • Korean journal of communication and information
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    • v.81
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    • pp.189-224
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    • 2017
  • The case of 'Paik Jong-moon's Taped Conversation,' has presented "an important and serious challenge to the freedom of the press and democracy" in South Korea. Nevertheless, this case has not been reported by the mainstream news media. It has also been forgotten without a proper fact-finding or investigation by regulatory agencies, like The Foundation for Broadcast Culture, The Korea Communications Commission, or The National Assembly. This study aims to examine why the above has happened through in-depth interviews of reporters and TV producers, senior journalists, former and incumbent commissioners of the broadcasting regulatory agencies, and experts of the industry, as well as literature research. Here, I present three answers. First, I found two reasons the mainstream press has ignored this incident. 1) It serves for political interests instead of reporting truth. 2) Public broadcasters' watchdog role has been neutralized. Second, regulatory agencies like The Foundation for Broadcast Culture, The Korea Communications Commission and The National Assembly are ruled by political tribalism. The ruling party's members of the National Assembly and these agencies were reluctant to investigate allegations surrounding Paik Jong-moon, such as illegal dismissals, illegal intervention in programming or production, illegal recruitment and illegal business deals. That's because they considered CEO Paik an ally. Using their majority power, they have rejected the request from opposition-affiliated commissioners or from opposition lawmakers to investigate the allegations. Third, there were no alternative forces within the public broadcasters to unveil the truth. In conclusion, the legal and institutional shake-up of corporate governance is urgently needed for public broadcasters and broadcasting regulatory agencies.

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The Behavior of Piled Bridge Abutments Subjected to Lateral Soil Movements - A Study on the Centrifuge Model Tests - (측방유동을 받는 교대말뚝기초의 거동분석 (I) - 원심모형실험 연구 -)

  • 서정주;서동희;정상섬;김유석
    • Journal of the Korean Geotechnical Society
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    • v.19 no.1
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    • pp.5-19
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    • 2003
  • A series of centrifuge model tests were conducted to investigate the behavior of piled bridge abutments subjected to lateral soil movements induced by approach embankments. The effect of clay layer depth and the rate of embankment construction on piled bridge abutments are the main focus of this study. Tests were performed for two loading types: (1) incremental loading applied in six lifts to the final embankment height; (2) instant loading corresponding to the final embankment height applied in one lift quickly. A variety of instrumentations such as LVDTs, strain gauges, earth pressure transducers, and pore pressure transducers are installed in designed positions in order to clarify the soil-pile interaction and the short- and long-term behavior for piled bridge abutments adjacent to surcharge loads. Based on the results of a series of centrifuge model tests, the distribution of lateral flow induced by staged embankment construction has trapezoidal distribution. The maximum lateral soil pressure is about 0.75$\gamma$H at surcharge loading stage, and about 0.35 $\gamma$H at over 80% consolidated stage.

Exploring Middle School Students' Learning Development through Science Magazine Project with Focus on the Perspective of Participation (과학 잡지 프로젝트를 통한 중학생의 학습 변화 탐색: 참여의 관점을 중심으로)

  • Lee, Min-Joo;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
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    • v.31 no.2
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    • pp.256-270
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    • 2011
  • This study was designed to explore how learners' participation develop if provided with opportunities for various scientific practices and experiences in writing science magazine articles as an extra-curricular club activity and what factors facilitate these participation development. Data from participant observations, in-depth interviews with students, and documents were used to extract the common characteristics of the practices. The learners' development was categorized into 3 stages in terms of participation in the community of practice: peripheral participation, transitional participation, and full participation. As participation develops, situational interest developed to individual interests and value attachment. Students sought to get ideas from every day life, and finally, in the stage of full participation, advances in writing showed the characteristics of knowledge transformation. Best of all, the participants enjoyed and valued their participation showing identities as journalists. The nature of science magazine article, external scaffolding, and internalization through enjoyment and value attachment appeared to be decisive factors that facilitate the development of participation. Student's enculturation of writing for learning offers a possibility that continue to do so, even after they have left formal schooling and make a basis for lifelong learning.

Educational Contents of 'Understanding of self as an adolescent' Unit to Build Adolescent Empowerment(I): comparison of Home Economics Textbooks of Korea and the U.S. (청소년의 임파워먼트 형성에 초점을 둔 '청소년의 이해' 단원의 한·미 교과서 교육내용 검토(제1보))

  • Suh, Min-Ji;Lee, Soo-Hee;Sohn, Sang-Hee
    • Journal of Korean Home Economics Education Association
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    • v.27 no.3
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    • pp.99-119
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    • 2015
  • The purpose of this study is to examine the educational contents of home economics textbooks that solely focus on forming adolescent empowerment. For this, an in-depth content analysis was conducted on the home economics textbooks in Korea and the U.S. The main results of this study are summarized as follows: First, the 23 content elements, which are designed to build adolescent empowerment, were ascertained: nine intrapersonal empowerment elements such as the self-identity, nine interpersonal empowerment elements such as the communication, and five social empowerment elements such as the leadership. Second, based on the content elements selected from above, the textbooks in Korea were observed to deal with 58% of the 23 content elements, while those in the U.S. discussed 90% of the 23 content elements. Korean textbooks primarily focused on helping students understand major concepts, whereas the U.S. textbooks focused primarily on helping students make connections between major concepts and their life. Lastly, both countries put the least amount of weight on social empowerment content elements(Korea: 37%, U.S.: 70%).

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The Impact of Grouping Methods on Free Inquiry Implementation: The Case of Two Middle Schools Adopting Different Grouping Methods (소집단 구성 방식이 자유 탐구 수행에 미치는 영향: 소집단 구성 방식을 달리한 두 중학교의 사례)

  • Park, Jae-Yong;Lee, Ki-Young
    • Journal of The Korean Association For Science Education
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    • v.32 no.4
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    • pp.686-702
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    • 2012
  • This study investigated the impact of grouping methods on free inquiry implementation through the use of mixed research methods. Some 113 7th graders and 2 science teachers in two middle schools participated in this study. The 113 students who participated in this study were grouped by homogeneity and heterogeneity according to scientific inquiry skills and personality types respectively, and performed free inquiry activities on the same subject for three weeks. Data were collected by means of a test on science inquiry skills and from focus group interviews with 36 students and in-depth interviews with 2 teachers. The quantitative results of this study showed that homogeneous grouping was more effective than heterogeneous grouping in improvement of scientific inquiry skills. Meanwhile, the qualitative results revealed both the students and teachers perceived that it was effective to compose a small group according to their affective quality than their cognitive quality. Particularly, most of the students preferred the method of small group from the personality types. Some students and both teachers proposed that it is necessary to collect enough information on students and to use them in mixture with the method of small group according to the affective quality.

The Case Study on Convergence Education in Akita International University (아키타 국제교양 대학의 융합교육에 대한 사례연구)

  • Yim, Myung-Seong
    • Journal of Digital Convergence
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    • v.14 no.6
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    • pp.371-380
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    • 2016
  • The aim of this case research is to describe the convergence education of Akita International University. Today, competition among universities in Korea are becoming more and more intensified, its strength is expected to continue to rise. In this situation, the Akita International University provides meaningful implications for universities in Korea. Universities in Japan are at similar situation in Korea. The unique values of Akita that we identified are twofold: The first is internationalization in education. The purpose of the internationalization is for Japanese students. For exchange students, AIU provides japan studies program and japan language program. To do this, AIU forms an international community to mingle Japanese students with foreign exchange students by living and learning together. Second thing is about international liberal arts education. The focus of international liberal arts education is that students acquire comprehensive range of skills and knowledge to build the intellectual foundation for specialist study by providing a broad range of academic disciplines. In doing so, students promotes learner autonomy. Unlike specialized education, in which students acquire an in-depth knowledge of a particular field, providing international liberal arts education is to find a field in which students want to study further. The implications and conclusions are discussed.

The Tokenization of Space and Cash Out without Debt: Focus on Security Token Offerings Using Blockchain Technology (공간의 토큰화와 빚 없이 현금 뽑기: 블록체인 기술을 활용한 증권형 토큰 발행을 중심으로)

  • Lee, Hoobin;Hong, Dasom
    • Journal of the Economic Geographical Society of Korea
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    • v.24 no.1
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    • pp.76-101
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    • 2021
  • This paper analyzes two cases of space tokenization, Meridio and QuantmRE, to explore the potential of tokenization as a new means of space financialization. Space tokenization is based on blockchain technology and security token offering (STO). Although some financial geographers noted the possible impact of blockchain technology on space financialization, it has not been examined in depth. Therefore, this paper demonstrates space tokenization cases in detail. Meridio and QuantmRE suggest financial structures that convert space into tokens based on fractional ownership transactions. QuantmRE, specifically, allows a homeowner to secure cash without either debt or ownership relinquishment through sales of tokenized home equity. As this method takes a form of sale transaction rather than a loan, it enables financial institutions to circumvent strengthened regulation on loans after the 2008 global financial crisis. Moreover, even "house poor" households, who own houses but lack cash due to excessive loans, can cash out from their properties through QuantmRE. As such, space tokenization enables financial institutions to overcome constrained conditions after the global financial crisis, thereby reproducing space financialization. Space tokenization also has the potential to geographically expand space financialization through stimulating investment in the depressed housing market.