• Title/Summary/Keyword: Research Guides

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Dynamic Characteristics of Linear Motion Supported by Rolling Ball Bearings (볼 베어링을 사용하는 선형 운동 가이드의 동적 특성)

  • Choi Jae Seok;Yi Yong-sub;Kim Yoon Young;Lee Dong Jin;Lee Sung Jin;Yoo Jeonghoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.9 s.90
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    • pp.868-876
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    • 2004
  • The linear motion(LM) guide using ball bearing has many advantages compared with conventional sliding guides. Therefore, LM guide using ball bearing has been widely used to increase the accuracy of the position of a system. This research investigates dynamic characteristics of LM guide through mainly linear analyses. Linear analysis is accomplished by Lagrange equation and the finite element method. And another trial that performs nonlinear analysis about one mode(bouncing mode) of LM guide from Hertzian contact theory is accomplished in the latter half of this research. Through nonlinear analysis we could observe the softening characteristic due to the Hertzian contact nonlinearity.

Research and Development Methodology for Practical Use of Accident Tolerant Fuel in Light Water Reactors

  • Kurata, Masaki
    • Nuclear Engineering and Technology
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    • v.48 no.1
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    • pp.26-32
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    • 2016
  • Research and development (R&D) methodology for the practical use of accident tolerant fuel (ATF) in commercial light water reactors is discussed in the present review. The identification and quantification of the R&D-metrics and the attribute of candidate ATF-concepts, recognition of the gap between the present R&D status and the targeted practical use, prioritization of the R&D, and technology screening schemes are important for achieving a common understanding on technology screening process among stakeholders in the near term and in developing an efficient R&D track toward practical use. Technology readiness levels and attribute guides are considered to be proper indices for these evaluations. In the midterm, the selected ATF-concepts will be developed toward the technology readiness level-5, at which stage the performance of the prototype fuel rods and the practicality of industrial scale fuel manufacturing will be verified and validated. Regarding the screened-out concepts, which are recognized to have attractive potentials, the fundamental R&D should be continued in the midterm to find ways of addressing showstoppers.

A Survey of Current Practices and Tools in Environmentally Conscious Electrical Appliances (가전에 있어서 친 환경 제품 개발의 평가기술 연구현황)

  • Kim, Young-Kyu;Jeong, Sang-Jin;Hwang, Jong-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.8
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    • pp.19-25
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    • 2000
  • Development of Environmentally conscious products in the electrical appliance industry is necessary not only for environmental law and green consumer but also for competitiveness by cost reduction. In this paper the current trends of evaluation tools are described. And practices in the development of environmentally conscious products are explained and improvement cases are presented by ways of design guides. The paper concludes with suggested future tasks which will need to be addressed in order that product designers can utilize the said tools effectively.

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The Examination for Design of Hatchcoverless Containerships (무개형 콘테이너선 설계에 관한 고찰)

  • Park, Myung Kyu;Shin, Yeong Sik
    • Journal of Korean Port Research
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    • v.5 no.1
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    • pp.3-22
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    • 1991
  • In recent years the hatchcoverless(or open-top) containerships have been evolving as a promising new concept for enhanced containership operations. The design concept of the hatchcoverless containership is innovative and appears to be worthwhile. especially from an operational viewpoint. The hatchcover and container lashing system have been eliminated and the containers are stacked in open hold fitted with cell guides. Thus this design concept can provide a more efficient and economically viable fleet due to the reduced time and cost of loading and unloading operations. Therefore turnaround time in port is also greatly reduced. This examination provides. brief background, advantages, brief review of new building containership, highlights of the pertinent areas requiring special consideration and recommendations of possible analyses herein.

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A Conceptual Model for IT Impact Research (정보기술 영향연구의 개념적 모형)

  • Jeon, Seong-Hyeon
    • Asia pacific journal of information systems
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    • v.6 no.2
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    • pp.201-220
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    • 1996
  • The effects of information technology on people and society, while being profusely laid out in academic and popular literature, are largely anecdotal, fragmented, and speculative, not adding up to a consistent theory of IT impact. This is attributed to a lack of a proper research model that guides and integrates the research. This paper examines several dimensions of the IT impact research that characterize and distinguish the research and develops a conceptual model of the IT impact research. Three dimensions are examined - the search domain, the concept of organization, and the level of analysis. The dimensions are combined to produce several conceptual domains, each with differing issues and characteristics for research, that constitute the IT impact research. A model of the IT impact research is developed which proposes a series of transition among the search domains. At the end, the implications of the research model are discussed.

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Analysis of Soil Contamination with Depth in Non-sanitary Closed Waste Landfill (비위생 사용종료매립장의 심도별 토양오염도 분석)

  • Oh, Young-In;Kim, Kwan-Ho;Lee, Dong-Geon;Cho, Sook-Hee;Bak, Eun-Suk
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.1217-1224
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    • 2010
  • These days, the maintenance of closed waste landfill come to the fore social problem such as legal maintenance period, after closed maintenance deposits, stability evaluation guides and environmental survey for closed landfill management. Therefore the many non-sanitary closed waste landfill has been removed by selection and transfer to sanitary landfill and incineration. When the remove the non-sanitary landfill, the pollution level of bottom soil was investigated by related government law. In this case study, the soil contamination survey was performed to evaluate the pollution level of non-sanitary closed landfill bottom soil. Based on this study, the pollution level of studied non-sanitary landfill bottom soil was content with related government law for third area(factory, parking lot, gas station, road, railroad use etc.).

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Nonlinear Dynamic Buckling Behavior of a Partial Spacer Grid Assembly

  • Yoon, Kyung-Ho;Kang, Heung-Seok;Kim, Hyung-Kyu;Song, Kee-Nam;Jung, Yeon-Ho
    • Nuclear Engineering and Technology
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    • v.33 no.1
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    • pp.93-101
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    • 2001
  • The spacer grid is one of the main structural components in the fuel assembly, which supports the fuel rods, guides cooling water, and protects the system from an external impact load, such as earthquakes. Therefore, the mechanical and structural properties of the spacer grids must be extensively examined while designing them. In this paper, a numerical method for predicting the buckling strength of spacer grids is presented. Numerical analyses on the buckling behavior of the spacer grids are performed for a various array of sizes of the grids considering that the spacer grid is an assembled structure with thin-walled plates and imposing proper boundary conditions by nonlinear dynamic finite element method using ABAQUS/Explicit. Buckling tests on several numbers of specimens of the spacer grid were also carried out in order to compare the results between the test and the simulation result. The drop test is accomplished by dropping a carriage on the specimen at a pre-determined position. From this test, the specimens are buckled only at the uppermost and the lowermost layer among the multi-cells, which is similar to the local buckling at the weakest point of the grid structure. The simulated results also similarly predicted the local buckling phenomena and were found to give good correspondence with the experimental values for the thin-walled grid structures.

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Automatic Extraction of Building Heights from Aerial Digital Images

  • Yom, Jae-Hong;Lee, Dong-Cheon;Kim, Jeong-Woo;Kwon, Jay-Hyon;Kim, Deok-In
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.517-517
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    • 2002
  • Recently in the field of telecommunication, there is much interest in geo-surface characteristics of urban areas. Geophysical properties of urban features are now incorporated with accurate positional information to model the telecommunication environment. In this study, three-dimensional buildings are geometrically reconstructed from existing vector maps and aerial images. Accurate digital vector maps are easily available in Korea. However existing maps, which had been produced for GIS applications, do not have height information which is critical to three dimensional building reconstruction. Image matching techniques were applied to aerial image stereopairs to automatically extract the height information of buildings. Planimetric coordinates from vector maps were used as initial guides in the process. Future studies will be undertaken to link geophysical properties to the three-dimensional spatial objects reconstructed from this study thus bringing the telecommunication environment model closer to reality.

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Considerations of the Optimized Protective Action Distance to Meet the Korean Protective Action Guides Following Maximum Hypothesis Accidents of Major KAERI Nuclear Facilities

  • Goanyup Lee;Hyun Ki Kim
    • Journal of Radiation Protection and Research
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    • v.48 no.1
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    • pp.52-57
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    • 2023
  • Background: Korea Atomic Energy Research Institute (KAERI) operates several nuclear research facilities licensed by Nuclear Safety and Security Commission (NSSC). The emergency preparedness requirements, GSR Part 7, by International Atomic Energy Agency (IAEA) request protection strategy based on the hazard assessment that is not applied in Korea. Materials and Methods: In developing the protection strategy, it is important to consider an accident scenario and its consequence. KAERI has tried the hazard assessment based on a hypothesis accident scenario for the major nuclear facilities. During the assessment, the safety analysis report of the related facilities was reviewed, the simulation using MELCOR, MACCS2 code was implemented based on a considered accident scenario of each facility, and the international guidance was considered. Results and Discussion: The results of the optimized protective actions were 300 m evacuation and 800 m sheltering for the High-Flux Advanced Neutron Application Reactor (HANARO), the evacuation to radius 50 m, the sheltering 400 m for post-irradiation examination facility (PIEF), 100 m evacuation or sheltering for HANARO fuel fabrication plant (HFFP) facility. Conclusion: The results of the optimized protective actions and its distances for the KAERI facilities for the maximum postulated accidents were considered in establishing the emergency plan and procedures and implementing an emergency exercise for the KAERI facilities.

East Asian Journal of Business Economics and Strategy

  • KIM, Byoung-Goo;YOUN, Myoung-Kil
    • Journal of Research and Publication Ethics
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    • v.1 no.1
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    • pp.11-15
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    • 2020
  • Purpose: This study is to review and analyze orientation and strategy of the East Asian Journal of Business Economics and all of the published articles of 2013 to 2020 and to investigate the previous publication system and process in order to enhance the general quality of EAJBE. Research design, data and methodology: This paper applied a case study method and analyzed the previous published articles and system including homepage of East Asian Journal of Business Economics. Results: This journal strives to be the most globalized than other domestic journals in the field of management/economy, and since its inception in 2013, all the papers is written in English, and more than 40% of the contributors are overseas contributors, so it is developed by global strategies in a different direction from other domestic journals. Conclusions: The EAJBE provides the full text of the contributors' research ethics regulations to the online system, and mandates researchers to submit a pledge from the stage of the contribution. The journal provides clear criteria such as self-plagiarism and duplicates publication, and specifies the copyright agreement and submission application twice, and guides the contributors and the reviewers to use the system in advance.