• Title/Summary/Keyword: Be

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Crystallization Behavior of Amorphous Ti-Be Alloys as Filler Metals for Joining Zircaloy-4 Tubes and Microstructures of the Brazed Zones (지르칼로이-4 브레이징용 비정질 Ti-Be 용가재의 결정화 거동 및 접합부 미세조직)

  • Kim, Sang-Ho;Go, Jin-Hyeon;Park, Chun-Ho
    • Korean Journal of Materials Research
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    • v.12 no.4
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    • pp.259-263
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    • 2002
  • Three different ribbons of amorphous $Til_{1-x}Be_x$ alloys such as $Ti_{0.59}Be_{0.41},\;Ti_{0.61}Be_{0.39}\;and\;Ti_{0.63}Be_{0.37}$ were made by melt-spinning method to be used as brazing filler metals for joining Zircaloy-4 nuclear fuel cladding tubes, and their crystallization behavior as well as microstructure of the brazed zone were examined. The crystallization behavior was investigated in teams of thermal stability, crystallization temperature and activation energy. The crystallization of the $Ti_{1-x}Be_x$ alloys proceeded in two steps by the formation of ${\alpha}$-Ti at a lower temperature and of TiBe at a higher temperature. The crystallization temperature and activation energy of $Ti_{1-x}Be_x$ alloys were higher and larger than those of $Zr_{1-x}Be_x$ alloys and PVD Be. Those resulted thinner joining layer with $Ti_{1-x}Be_x$ alloys, which kept sound thickness of Zircaloy-4 nuclear fuel cladding tubes after brazing. But in the brazed zones made by $Ti_{1-x}Be_x$ filler metals, a little solid-solution layers composed of Zr and Ti were formed toward the Zr cladding tube and Zr was detected in the brazed zones. Microstructure of brazed zone was changed from globular to dentrite with decreasing Be content in the $Ti_{1-x}Be_x$ filler metal.

ON POSITIVE IMPLICATIVE FILTERS IN BE-ALGEBRAS

  • Kim, Young Hee;Park, Jung Hee
    • Journal of the Chungcheong Mathematical Society
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    • v.27 no.3
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    • pp.419-426
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    • 2014
  • In this paper, we introduce the notion of a positive implicative filter in BE-algebras. We show that every positive implicative filter is a filter in BE-algebras. We give some examples that a filter may not be a positive implicative filter and also a positive implicative filter may be not an implicative filter in BE-algebras. We also give some equivalent conditions of a positive implicative filter in BE-algebras.

Sapphire Enhancement with BeO Powder Source (BeO를 확산원으로 한 사파이어의 향상처리)

  • Song, Oh-Sung;Kim, Sang-Yeop
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.2
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    • pp.105-109
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    • 2005
  • We heat treated pure sapphire samples at $1800^{\circ}C{\sim}100$ hours in BeO-${Al_2}{O_3}$ powder by varying BeO contents of $5{\sim}50\;wt%$ in order to quantify the BeO diffusion enhancement for corundum gem stones. We investigated the heat treated samples with visual evaluation, color coordination analysis, and surface roughness measurement. We confirmed that $Be^{2+}$ ions did not lead to orange color but to dark gray. The lightness in CIE Lab index decreased while surface roughness increased rapidly as BeO contents increased. We propose that BeO yellow color enhancement may be feasible only for $Fe^{3+}$ rich blue sapphires and sub-5% BeO content be appropriate to shorten post re- cutting process.

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A Grounded Theory Study on Substantials of Stress of Korean Wives (한국 주부들이 경험하는 스트레스 본질의 근거이론적 접근)

  • Yang, Koung-Hee;Chung, Ju-Yeon;Choi, Sun-Ha
    • Research in Community and Public Health Nursing
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    • v.6 no.2
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    • pp.183-196
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    • 1995
  • The purpose of this study was to construct a substantive theory about the substantials of stress of Korean Wives in the community. The subjects were 10 wives. In the process of data analysis, 'burden' was found to be the core phenomenon. And the properties of burden were 'burden of domestic economy', 'a sence of duty about the esteemed family of her husband', 'role burden in a family and her work place', and 'burden of conception'. Twenty five hypotheses were derived from the integration of categories. It is as follows : 1. The stronger the difference as perceiced by subjects, the stronger the burden will be. 2. The stronger the dissatisfaction, the stronger the burden will be. 3. The stronger the trouble, the stronger the burden will be.4. The stronger the worry, the stronger the burden will be. 5. The stronger the forcible demand, the stronger the burden will be. 6. The stronger the regret, the stronger the burden will be. 7. The rarer the communication, the stronger the burden will be. 8. The stronger the fatigue, the stronger the burden will be. 9. The stronger the anger, the stronger the burden will be. 10. The stronger the worrisome feeling, the stronger the burden will be. 11. The stronger the unbearable feeling, the stronger the burden will be. 12. The stronger the resentment. the stronger the burden will be. 13. The stronger the sence of insufficiency, the stronger the burden will be. 14. The stronger the estrangement, the stronger the burden will be. 15. The stronger the attachment, the stronger the burden will be.

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Management of Swimming Pool (수영장 관리)

  • Kim Kyong-Ho
    • Journal of environmental and Sanitary engineering
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    • v.4 no.1 s.6
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    • pp.37-42
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    • 1989
  • Management of Swimming pool is focused on Swimming pool samitation in relation with chlorination of swimming water and potable water, disposal of waste and excrement within the boundry of swimming pool that may be summerised as follows: 1. Chlorination of Swimming Water Residual chlorine must be kept within the range of $0.4\~0.6 mg/l$ and in case of chloramine should be $0.7\~1.0mg/l$ while swimming pool is in operation 2. Chlorination of potable Water Residual chlorine must be kept within the rangs of $0.2\~04 mg/l$ at all time 3. Disposal of litters must be kept in the water tight waste bin with fitted lid, and waste should not be overflow -out of the bin. When waste in landfilled, the sufficient amount of cover material should be used daily. 4. Disposal of excrement Toilet must be water-flush type. However, The establishment of pit latrine is unavoidable the excrement must be covered with lime or dirt so that excrement should not be exposed to air.

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Study on the construction of digital library (디지탈도서관의 구축을 위한 연구)

  • Seo, Whee
    • Journal of Korean Library and Information Science Society
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    • v.25
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    • pp.529-567
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    • 1996
  • This paper surveyed the theoretical backgrounds of digital library. Its definition and function and case studies, and basic skills for system construction of digital library were suggested. The differences between the traditional library and the digital library were compared. And the conditions that should be take into consideration of digital library construction were suggested. Suggestions are summarized as follows : 1. For the construction of digital library, library collection should be digitalized by using CD-ROM and commercial online services. 2. The digitalization of library collection should be planned by subject sharing between the libraries. For the control of this cooperation, the orgnization to propel the digitalization should be established. And it is necessary to enact the standards for the digital library. 3. The connection between MARC formatted bibliographic database and full-text should be studied. 4. All the types of information about texts, pictures, sounds and if films should be also digitalized. 5. To satisfy the needs of many users, we have to establish the various users's interface which is fitted for several kinds of users. 6. When a digital library was constructed, the copyright and resources sharing must be guranteed depending on the cost of database's usage. 7. Because the digitalization of library will be related to the various kinds of libraries, the interface for resources sharing will be constantly concerned. 8. The sharing of information resources between the libraries will be enacted on the Internet. And we must be interested in various internet tools such as telecommunication softwares, media convert programs, etc. 9. By training staffs continously, all libraries must be ready to come the library in the future.

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Political Implication on the Genetically Modified Crops (유전자(遺傳子) 변형(變形) 농산물(農産物)에 관한 정책적(政策的) 함의(含意))

  • Shin, Young In;Park, In Shik
    • Korean Journal of Agricultural Science
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    • v.26 no.2
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    • pp.116-129
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    • 1999
  • The objectives of the study mainly concentrated on identifying the political implication on genetically modified crops considering production potentials and problems. It is found that the comprehensive evaluation of the genetically modified crops could not be concluded and compromised in a word on account of the polarization and parallelism of the positive and negative benefits of genetically modified crops just like as the rail way. The genetically modified crops will be contributed to solving the food shortage problems in the world, when the issues such as food safety, ecological disturbance and loss and degradation of biodiversity can be guaranteed in transparency. And when the trade morality of the multi-national enterprises be accepted by the genetically modified crops consumers, the potentiality of genetically modified crops will be realized greatly. By the way, the first problems will be expected to be solved by scientific development. If the food safety of the genetically modified technology be verified in transparency, it will be greatly contributed to solve food problems of human beings in the world. But the second problem could not be expected to be easily solved from the view point of capital property. In conclusion, the genetically modified technology will be made a severe sense of incongruity and a seed of fire on it will be remained persistently. According to the results based on the analysing the genetically modified crops potentiality and problems, it was identified that the ex-ante preparation of counter-measures and actions on it should be necessary. Accordingly this study has recommended that how and what the R&D policy on genetically modified crops be established and suggested how to carried out the industrial and economic policy together with international negotiation, and organizational and institutional rearrangement and etc.

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FUZZY BE-ALGEBRAS

  • Ahn, Sun-Shin;Kim, Young-Hee;So, Keum-Sook
    • Journal of applied mathematics & informatics
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    • v.29 no.3_4
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    • pp.1049-1057
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    • 2011
  • In this paper, we fuzzify the concept of BE-algebras, investigate some of their properties. We give a characterization of fuzzy BE-algebras, and discuss a characterization of fuzzy BE-algebras in terms of level subalgebras of fuzzy BE-algebras.

CLOSED AND DENSE ELEMENTS OF BE-ALGEBRAS

  • Prabhakar, M.Bala;Vali, S.Kalesha;Sambasiva Rao., M.
    • Journal of the Chungcheong Mathematical Society
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    • v.32 no.1
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    • pp.53-67
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    • 2019
  • The notions of closed elements and dense elements are introduced in BE-algebras. Characterization theorems of closed elements and closed filters are obtained. The notion of dense elements is introduced in BE-algebras. Dense BE-algebras are characterized with the help of maximal filters and congruences. The concept of D-filters is introduced in BE-algebras. A set of equivalent conditions is derived for every D-filter to become a closed filter.