• Title/Summary/Keyword: Bottom-up development

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Development of Liquid Cadmium Cathode Structure for the Inhibition of Uranium Dendrite Growth (수지상 우라늄 성장억제를 위한 액체카드뮴 음극구조 개발)

  • Paek, Seung-Woo;Yoon, Dal-Seong;Kim, Si-Hyung;Shim, Jun-Bo;Ahn, Do-Hee
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.1
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    • pp.9-17
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    • 2010
  • The LCC (Liquid Cadmium Cathode) structure to be developed for inhibiting the formation and growth of the uranium dendrite has been known as a key part in the electrowinning process for the simultaneous recovering of uranium and TRU (TRans Uranium) elements from spent fuels. A zinc-gallium (Zn-Ga) experimental system which is able to be functional in aqueous condition and normal temperature has been set up to observe the formation and growth phenomena of the metal dendrites on liquid cathode. The growth of the zinc dendrites on the gallium cathode and the performance of the existing stirrer type and pounder type cathode structure were observed. Although the mechanical strength of the dendrites appeared to be weak in the electrolyte and easily crashed by the various cathode structures, it was difficult to effectively submerge the dendrite into the bottom of the liquid cathode. Based on the results of the aqueous phase experiments, a lab-scale electrowinning experimental apparatus which are applicable to the development of LCC srtucture for the electrowinning process was established and the performance tests of the different types of LCC structure were conducted to prohibit the uranium dendrite growth on LCC surface. The experimental results of the stirrer type LCC structures have shown that they could not effectively remove the uranium dendrites growing at the inner side of the LCC crucible and the performances of the paddle and harrow type LCC structure were similar. Therefore a mesh type LCC structure was developed to push down the uranium dendrites to the bottom of the LCC crucible growing on the LCC surface and at the inner side of the crucible. From the experimental results for the performance test of the mesh type LCC structure, the uranium was recovered over 5 wt% in cadmium without the growth of uranium dendrites. After completion of the experiments, solid precipitates of the bottom of the LCC crucible were identified as an intermetallic compound (UCd11) by the chemical analysis.

Automatic Extraction of Abstract Components for supporting Model-driven Development of Components (모델기반 컴포넌트 개발방법론의 지원을 위한 추상컴포넌트 자동 추출기법)

  • Yun, Sang Kwon;Park, Min Gyu;Choi, Yunja
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.8
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    • pp.543-554
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    • 2013
  • Model-Driven Development(MDD) helps developers verify requirements and design issues of a software system in the early stage of development process by taking advantage of a software model which is the most highly abstracted form of a software system. In practice, however, many software systems have been developed through a code-centric method that builds a software system bottom-up rather than top-down. So, without support of appropriate tools, it is not easy to introduce MDD to real development process. Although there are many researches about extracting a model from code to help developers introduce MDD to code-centrically developed system, most of them only extracted base-level models. However, using concept of abstract component one can continuously extract higher level model from base-level model. In this paper we propose a practical method for automatic extraction of base level abstract component from source code, which is the first stage of continuous extraction process of abstract component, and validate the method by implementing an extraction tool based on the method. Target code chosen is the source code of TinyOS, an operating system for wireless sensor networks. The tool is applied to the source code of TinyOS, written in nesC language.

Counter-Current Flow Limit of a Vertical Two Phase (Water/Air) Flow (상반류(물/공기) 유동한계에 관한 연구)

  • 오율권;조상진;김상녕;이종원
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.1
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    • pp.308-322
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    • 1991
  • A set of experiments of Counter-Current Flow Limit(CCFL or Flooding) was performed to improve the drawbacks of Wallis' Correlation which neglects the effects of channel size, channel length, injection method and the boundary conditions at the inlet of liquid and gas phase. In these experiments using water and air, the followings were found ; (i) The effects of channel size and length were quite significant. In large tubes(D>20mm), the flooding front occurred at the bottom of the channel and when the gas flow increased the front moved upward ; however, in small tubes(D<20mm), there were no upward movement of flooding front and the flooding just occurred at the liquid inlet. (ii) The effect of water inlet device was not as significant as that of channel length though the inlet boundary conditions could affect the flow development and flooding afterward. (iii) Once the flooding front reached the inlet of water injection device, an newly reduced flow condition was set up and resulted in another flooding corresponding to the new condition.

Development of Stress Equations of Jointed Concrete Pavement using Finite Element Method (유한 요소법을 이용한 줄눈 콘크리트 포장 응력식 개발)

  • Jung, Kil-Su;Kim, In-Tai;Ryu, Sung-Woo;Cho, Yoon-Ho
    • International Journal of Highway Engineering
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    • v.10 no.2
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    • pp.167-181
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    • 2008
  • A pavement structure analysis model plays a very important role which can correlate input variables to performance models. In this research, a standard shell element model was developed by use of the ABAQUS program so that behaviors of concrete pavements be analyzed. The model was verified in terms of its accuracy by way of comparing the results to those gathered from closed-form Solutions, the Everfe program, and the ABAQUS program with a solid model. Many input variables were analyzed in the model, and the results were stored in a database. Based on the SPSS program, stress equations with respect to temperature and curling effects were developed. All models gave over 0.90 of R2 value except the case considering top-down curling (R2=0.86)

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The Self-Sufficiency Experience of Korean-American Single Mothers with the History of Domestic Violence in Poverty (미국 한인 가정폭력피해 한부모 빈곤여성들의 자활 경험)

  • Chong, Hyesuk
    • Korean Journal of Social Welfare
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    • v.65 no.4
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    • pp.245-269
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    • 2013
  • Self-sufficiency has been recognized as one of the most important welfare goals for women in the domestic violence field since the welfare reform in the U.S. A qualitative research design was conducted to explore the self-sufficiency experience of Korean-American single mothers with the history of domestic violence in poverty. The meaning of 'self-sufficiency' to participants is that a continuing task or process in life to move toward being independent mentally as well as economically. Their challenges toward self-sufficiency include the period of restoration of their potentials for self-sufficiency destroyed by domestic violence victimization and divorce, and the period of developing their sustainability for self-sufficiency. Their needs for 'help and support similar to care from the woman's parents' home', 'welfare service of select and concentration', 'mature dependency and self-sufficiency', and 'self-sufficiency from survival to dream come true' to cope with the challenges formentioned are reported. Concrete strategies for the development of self-sufficiency polices and services sensitive to immigrant single mothers with the history of domestic violence are suggested.

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Full Duplex Robot System for Transferring Flat Panel Display Glass (디스플레이용 판유리 이송을 위한 양방향 이송 로봇장치)

  • Lee, Dong Hun;Lee, Chibum;Kim, Sung Dong;Cho, Young Hak
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.6
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    • pp.996-1002
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    • 2013
  • This study addresses the development of a full duplex robotic system for transferring flat-panel display glass. We propose to accomplish this using a bidirectional linear transfer mechanism in place of the conventional rotary transfer mechanism. The developed full duplex robot comprises a driving part that carries the glass panel laterally, vertical part that can be moved up and down by means of a ball screw and linear motion guide arrangement, and hand part that slides by the cylinder of the driving part along the guide rail with a V-guide bearing attached to the bottom of the support. In addition, an alignment part prevents the hand part from derailing and holds the hand part while the driving part moves horizontally. The full duplex robot lifts and drives a glass panel directly while transferring it to the buffer and does not require rotational motion. Therefore, both transferring and stacking are realized with a single device. This device can be used in existing industrial facilities as an alternative to existing industrial robots in current as well as future process lines. The proposed full duplex robot is expected to save considerable amounts of time and space, and increase product throughput.

A Comparative Study on the Local Governments' Environmental Impact Assessment Systems between Korea and Japan I - forcusing on target projects and assessment items - (한국과 일본의 지방자치단체 환경영향평가 제도 비교 연구 I - 대상사업 및 평가항목을 중심으로 -)

  • Sung, Hyun-Chan;Kang, Myung-Soo
    • Journal of Environmental Impact Assessment
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    • v.13 no.2
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    • pp.57-71
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    • 2004
  • This study aims to review the environmental impact assessment systems of Japanese local governments, to compare its outcome with the systems of Korean local governments, and to suggest the development direction for the environmental impact assessment systems of Korean local governments based on the result. The study results showed that, first, due to distinction in the political systems of Japan and Korea, while Japan has bottom-up environmental impact assessment systems, Korea has topdown environment impact assessment systems. Second, although introduction of national systems on planning was put on hold as a future initiative, local governments including Tokyo and Saitama are experimenting evaluation procedures tailored to local features by legislating them as regulations. On the other hand, while 'prior environmental review system' was in effect as a national system, nothing was practiced at all by local governments. Third, in a total of 47 Japanese local governments, about 45 projects and 44 assessment items were added to local government environmental impact assessment only and designated as target projects and assessment items. Fourth, in both national and local environment impact assessment systems in Japan, screening procedures to determine assessment by separating into Type 1 projects and Type 2 projects and scoping procedures to discuss assessment items in advance were introduced and in effect. This Japanese EIA system may serve as a good reference to the Korean national and local government EIA systems.

Numerical Solution of Second Order Linear Partial Differential Equations using Agricultural Systems Application Platform (농업시스템응용플랫폼을 이용한 2계 편미분 방정식의 해석)

  • Lee, SungYong;Kim, Taegon;Suh, Kyo;Han, Yicheol;Lee, Jemyung;Yi, Hojae;Lee, JeongJae
    • Journal of The Korean Society of Agricultural Engineers
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    • v.58 no.1
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    • pp.81-90
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    • 2016
  • The Agricultural Systems Application Platform (ASAP) provides bottom-up modelling and simulation environment for agricultural engineer. The purpose of this study is to expand usability of the ASAP to the second order partial differential equations: elliptic equations, parabolic equations, and hyperbolic equations. The ASAP is a general-purpose simulation tool which express natural phenomenon with capsulized independent components to simplify implementation and maintenance. To use the ASAP in continuous problems, it is necessary to solve partial differential equations. This study shows usage of the ASAP in elliptic problem, parabolic problem, and hyperbolic problem, and solves of static heat problem, heat transfer problem, and wave problem as examples. The example problems are solved with the ASAP and Finite Difference method (FDM) for verification. The ASAP shows identical results to FDM. These applications are useful to simulate the engineering problem including equilibrium, diffusion and wave problem.

A Study on the providing urban planing information in the homepage of local governments (지방자치단체 홈페이지의 도시계획정보 제공실태 평가를 위한 지표개발 연구)

  • 최봉문
    • Proceedings of the Korea Contents Association Conference
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    • 2003.05a
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    • pp.237-244
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    • 2003
  • With the rapid development of information and communication technologies(ICTs) and internet technology and the explosive increasing of internet users, we can find almost every municipal information of local governments by visiting the home page without visiting the city hall personally. And in the case of urban planning information they provide many kinds of information to inform the policy and results of urban planning to citizens The differences of urban planning information from other municipal information, at first many information of urban planning should be presented as spatial data, so we have to provide the geographic information with internet GIS, and second to realize bottom-up decision making process the exchanging of information between citizen and government should be adopted as bulletin board system(BBS) and an questionnaire in internet In this paper I evaluated the sites of urban planning information in the homepage of local governments by many index. the index are composed with 4 categories 20 items on information providing, 3 categories 12 items on communication, and 2 categories 8 items on internet GIS. And as a result I introduce some high scored sites at each category, and propose that we have to recognize the internet as the technological media to broaden the opportunities for the community people to participate in the policy-making in reference to their political demands.

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The Wind Effect on the Cold Water Formation Near Gampo-Ulgi Coast (감포-울기 연안해역에서 발생하는 냉수대 현상과 해상풍과의 관계)

  • LEE Dong-Kyu;KWON Jae-Il;HAHN Sang-Bok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.3
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    • pp.359-371
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    • 1998
  • The cold water event near Gampo-Ulgi coast in summers between 1987 and 1994 are studied using sea surface temperature records at the coastal stations, ocean winds measured by SSM/I and AVHRR SST images. The response time of the cold water events by upwelling is less than two days and surface cold water expands up to the Ulleung Island. An analysis of 61 upwelling favorable winds indicates that the surface water temperature drops more than $1^{\circ}C\;in\;80\%$ of the south-westerly wind events. The linear correlation coefficient between wind impulses and the maximum temperature drops is good (0.6). It is found that the major cause of the cold water events is the along-shore wind in summer. The bottom topography and off-shore direction of the East Korean Warm Current by the potential vorticity conservation near Gampo coast also contribute the formation of the cold water along the southeast coast of Korea.

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