• Title/Summary/Keyword: science modules

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A Selecting Model for the Technology Modular Alternatives Based on Development Effectiveness (개발효용성에 근거한 기술대체모듈의 선정모형)

  • Kim, Ki-Chan;Ahn, Ki-Hyun;Kang, Il-Jung;Kwon, Cheol-Shin
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2007.11a
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    • pp.152-155
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    • 2007
  • The object of this research is to evaluate the priority of R&B project alternatives which were already screened by both feasibility and suitability of technological performance. This research is a selection model for R&D project alternatives after setting phase. And it is designed by CHP model which include individual and mutual weights. This model have 5 steps. (1) Setting Technology-Modules derived on the setting phase (2) Presenting the evaluation standards divided with 'M-Field' and 'T-Field' (3) Assessing the evaluation standard and technology modules (4) Obtaining and integrating the individually and mutually effective weights (5) Selecting the technology modules based on the priority of order by CHP. Through these steps, this model can suggest the evaluation way from specific technology levels to project level. And it can be guaranteed to perform the selected module set.

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Design Study of a Korean Mars Mission

  • Lee, Eun-Seok;Chang, Keun-Shik;Park, Chul
    • International Journal of Aeronautical and Space Sciences
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    • v.5 no.2
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    • pp.54-61
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    • 2004
  • In this paper we carried out a design study for an unmanned Mars missionsuitable for Republic of Korea. The mission will use a KSLV series launch system,which is to place a one tonne payload into the LEO. We calculated the velocityincrements(AV) required for departure from Earth and insertion into the orbitaround Mars based on the mission opportunity data provided by NASA. Two typesof Mars modules - entry type and orbiter type - were considered in this studyWe calculated the mass of TPS(therma1 protection system) for the entry tvpe Marsmodule based on the heat transfer rate and heat load from the Mars atmosphere tothe surface of the TPS. The heat transfer rate and heat load were obtained throughan entry trajectory calculation. For the orbiter type Mars module, we calcuIated themass breakdown of the additional spacecraft which is to insert the Mars moduleinto the orbit around Mars. Other mass items were determined by proportioningfrom the existing Mars modules. This paper finally proposes the payload capacitiesfor each types of Mars modules.

Development of Copper and Copper Oxide Removal Technology Using Supercritical CO2 and Hexane for Silicon Solar Cell Recycling (실리콘 태양전지 재자원화를 위한 초임계 CO2 및 헥산을 이용한 구리 및 산화구리 제거기술 개발)

  • Lee, Hyo Seok;Cho, Jae Yu;Heo, Jaeyeong
    • Current Photovoltaic Research
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    • v.7 no.1
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    • pp.21-27
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    • 2019
  • Lifetime of Si photovoltaics modules are about 25 years and a large amount of waste modules are expected to be discharged in the near future. Therefore, the extraction and collection of valuable metals out of discharged Si modules will be one of the important technologies. In this study, we demonstrated that supercritical $CO_2$ extraction method can be effectively used to remove Cu, one of the abundant elements in the module, as well as its oxide form, $Cu_2O$. Especially, we proved that the addition of hexane as co-solvent is effective for the removal of both materials. The optimal ratio of $CO_2$ and hexane was 4:1 at a fixed temperature and pressure of $250^{\circ}C$ and 250 bar, respectively. In addition, it was proven that the removal of $Cu_2O$ was preceded via reduction of $Cu_2O$ to Cu.

Effect of two way thermal hydraulic-fuel performance coupling on multicycle depletion

  • Awais Zahur;Muhammad Rizwan Ali;Deokjung Lee
    • Nuclear Engineering and Technology
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    • v.55 no.12
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    • pp.4431-4446
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    • 2023
  • A Multiphysics coupling framework, MPCORE, has been developed to analyze safety parameters using the best estimate codes. The framework contains neutron kinetics (NK), thermal hydraulics (TH), and fuel performance (FP) codes to analyze fuel burnup, radial power distribution, and coolant temperature (Tbc). Shuffling and rotation capabilities have been verified on the Watts Bar reactor for three cycles. This study focuses on two coupling approaches for TH and FP modules. The one-way coupling approach involves coupling the FP code with the NK code, providing no data to the TH modules but getting Tbc as boundary condition from TH module. The two-way coupling approach exchanges information from FP to TH modules, so that the simplified heat conduction solver of the TH module is not used. The power profile in both approaches does not differ significantly, but there is an impact on coolant and cladding parameters. The one-way coupling approach tends to over-predict the cladding hydrogen concentration (CHC). This research highlights the difference between one-way and two-way coupling on critical boron concentration, Tbc, CHC, oxide surface temperature, and pellet centerline temperature. Overall, MPCORE framework with two-way coupling provides a more accurate and reliable analysis of safety parameters for nuclear reactors.

Implementing Instructional Modules for Engineering Ethics into Engineering Curricula (공학윤리 교육모듈 컨텐츠를 이용한 전공교과목에서의 공학윤리 교육)

  • Lee, Young-Nam;Kim, Dae-Wook;Yu, Ji-Beom;Hwang, Sung-Ho;Kim, Hyun-Soo
    • Journal of Engineering Education Research
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    • v.10 no.4
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    • pp.78-92
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    • 2007
  • This study presents how the engineering ethics instructional modules have been developed based on Korean culture and how they are implemented into the existing engineering curricula at Sungkyunkwan University. The engineering ethics instructional modules were designed to be taught by engineering faculty members who did not have any teaching experience in ethics. As a result, it was determined that the engineering ethics instructional modules should include a detailed instructor lesson plan and all supporting resources such as slides (Power Point base), and handouts, or assessment units (pre- and post-test). Two 75 minute modules developed in this study consist of the diverse instructional activities for various student group sizes. In order to improve students' interests and classroom attention, various visual and audio resources such as famous movies, cartoons, and poems were included in the instructional resources. In addition, a number of case studies which might happen in the students' daily lives were chosen. The resulting ethical module No. 1 has been instructed in the existing engineering classes during the 1st semester in 2007. Overall, the students reported positive impressions of the modules and the faculty members also reported favorable perceptions of the modules. Also, team based activities encouraged students to participate in constructing the event trees, which are a basic analysis tool for ethics case studies. The results of this study will provide a guideline of implementing engineering ethics into the engineering curricula to other engineering programs and schools.

Heat Dissipation Technology of IGBT Module Package (IGBT 전력반도체 모듈 패키지의 방열 기술)

  • Suh, Il-Woong;Jung, Hoon-Sun;Lee, Young-Ho;Kim, Young-Hun;Choa, Sung-Hoon
    • Journal of the Microelectronics and Packaging Society
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    • v.21 no.3
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    • pp.7-17
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    • 2014
  • Power electronics modules are semiconductor components that are widely used in airplanes, trains, automobiles, and energy generation and conversion facilities. In particular, insulated gate bipolar transistors(IGBT) have been widely utilized in high power and fast switching applications for power management including power supplies, uninterruptible power systems, and AC/DC converters. In these days, IGBT are the predominant power semiconductors for high current applications in electrical and hybrid vehicles application. In these application environments, the physical conditions are often severe with strong electric currents, high voltage, high temperature, high humidity, and vibrations. Therefore, IGBT module packages involves a number of challenges for the design engineer in terms of reliability. Thermal and thermal-mechanical management are critical for power electronics modules. The failure mechanisms that limit the number of power cycles are caused by the coefficient of thermal expansion mismatch between the materials used in the IGBT modules. All interfaces in the module could be locations for potential failures. Therefore, a proper thermal design where the temperature does not exceed an allowable limit of the devices has been a key factor in developing IGBT modules. In this paper, we discussed the effects of various package materials on heat dissipation and thermal management, as well as recent technology of the new package materials.

Room-temperature Preparation of Al2O3 Thick Films by Aerosol Deposition Method for Integrated RE Modules

  • Tsurumi, Takaaki;Nam, Song-Min;Mori, Naoko;Kakemoto, Hirofumi;Wada, Satoshi;Akedo, Jun
    • Journal of the Korean Ceramic Society
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    • v.40 no.8
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    • pp.715-719
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    • 2003
  • The Aerosol Deposition (AD) process will be proposed as a new fabrication technology for the integrated RF modules. $\alpha$-A1$_2$O$_3$ thick films were successfully grown on glass and Al substrates at room temperature by the AD process. Relative dielectric permittivity and loss tangent of the $Al_2$O$_3$ thick films on Al showed 9.5 and 0.005, respectively. To form microstrip lines on aerosol-deposited A1903 thick films, copper electroplating and lithography processes were employed, and the square-type cross section with sharp edges could be obtained. Low-pass LC filters with 10 GHz cutoff frequency were simulated by an electromagnetic analysis, exhibiting the validity of the AD process as a fabrication technology f3r integrated RF modules.

NAVER : Design and Implementation of Networked Virtual Environments Based on PC Cluster (NAVER : PC 클러스터 기반의 분산가상환경 커널 설계 및 구현)

  • Park, Chang-Hoon;Ko, Hee-Dong;Changseok Cho;Ahn, Hee-Kap;Han, Yo-Sub;Kim, Tai-Yun
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2002.05a
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    • pp.221-228
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    • 2002
  • The NAVER is based on a cluster of low-cost personal computers. The goal of NAVER is to provide flexible, extensible, scalable and re-configurable framework for the diverse virtual environments especially for Gamsung research experiments. Personal computers are divided into three servers are according to their specific functions: Render Server, Device Server and Control Server. While Device Server contains external modules requiring event-based communication for the integration, Control Server contains external modules requiring synchronous communication every frame. And, the Render Server consists of 5 managers: Scenario Manager, Event Manger, Command Manager, Interaction Manager and Sync Manager. In this paper, we discuss NAVER as effective distributed system and its application to Gamsung experiment.

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A Simple GUI-based Sequencing Format Conversion Tool for the Three NGS Platforms

  • Rhie, A-Rang;Yang, San-Duk;Lee, Kyung-Eun;Thong, Chin Ting;Park, Hyun-Seok
    • Genomics & Informatics
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    • v.8 no.2
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    • pp.97-99
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    • 2010
  • To allow for a quick conversion of the proprietary sequence data from various sequencing platforms, sequence format conversion toolkits are required that can be easily integrated into workflow systems. In this respect, a format conversion tool, as well as quality conversion tool would be the minimum requirements to integrate reads from different platforms. We have developed the Pyrus NGS Sequencing Format Converter, a simple software toolkit which allows to convert three kinds of Next Generation Sequencing reads, into commonly used fasta or fastq formats. The converter modules are all implemented, uniformly, in Java GUI modules that can be integrated in software applications for displaying the data content in the same format.

The International Trend of Science Education Reform Program 'Science-Technology-Society'-The Case of Iowa Chautauqua Program- (과학교육 개혁 프로그램 '과학-기술-사회'의 국제적 동향-아이오와 프로그램을 중심으로-)

  • Cho, Jung-Il
    • Journal of The Korean Association For Science Education
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    • v.18 no.1
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    • pp.71-82
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    • 1998
  • The main purpose of Iowa Chautauqua Program(ICP) and Iowa-Scope, Sequence. and Coordination (Iowa-SS&C) was to educate K-12 science teachers so that they could teach science in a human context using the constructivist strategies. The major task for the participating teachers to perform was to develop modules with the emphasis on STS and constructivist approach. which were supposed to be taught in the respective classrooms. Teachers worked together for two weeks for the development of modules during the summer, and attempted the modules with their students. The participating teachers met regularly during the autumn semester to share and reflect their experiences and obtain additional information on science education reform and its implications. During the winter break. the teachers improved and extended the STS modules. The Iowa Chautauqua Program and Iowa-SS&C had two important implications for Korean science education. First, they made the most of the resources they had in order to provide the practicing teachers with recent research findings on the nature of science. science learning and teaching, that is. the constructivist approach. Second, they emphasized both cooperation of teachers and long-term training to realize the reform in school science education.

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