• 제목/요약/키워드: Be별

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

  • 김상호;고진현;박춘호
    • 한국재료학회지
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    • 제12권4호
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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
    • 충청수학회지
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    • 제27권3호
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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.

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

  • 송오성;김상엽
    • 한국산학기술학회논문지
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    • 제6권2호
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    • pp.105-109
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    • 2005
  • 보석용 사파이어의 색향상 Be처리를 정량화하기 위해서 BeO를 확산 원으로 하여 알루미나(${Al_2}{O_3}$)분말과 $5{\sim}50wt%$ 범위에서 혼합하여 탄소발열체로 대기 중에서 $1800^{\circ}C$에서 100시간동안 순수한 단결정 사파이어 기판을 확산시켰다. 조성에 따라 처리된 사파이어를 육안검사, 색좌표검사, 표면조도의 변화검사를 실시한 결과, $Be^{2+}$ 원소는 알려진 바와 같이 순수한 사파이어에서는 발색원소로 작용하지 않았고 국부적인 회색의 원인이 되었다. 조성증가에 따라 확산양의 증가에 따라 급격히 Lab지수에서 광택지수(L)가 감소하였으며 표면조도가 증가하는 특징이 있었다. 기존에 알려진 블루사파이어의 오렌지 사파이어로의 향상을 위해서는 처리 후 표면조도가 작아서 재연마를 생략할 수 있는 5% 이하 BeO의 저조성 범위에서 순수한 커런덤이 아닌 $Fe^{3+}$ 성분이 많은 원석의 채용이 필요함을 확인하였다.

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

  • 양경희;정주연;최선하
    • 지역사회간호학회지
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    • 제6권2호
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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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수영장 관리 (Management of Swimming Pool)

  • 김경호
    • 환경위생공학
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    • 제4권1호
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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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디지탈도서관의 구축을 위한 연구 (Study on the construction of digital library)

  • 서휘
    • 한국도서관정보학회지
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    • 제25권
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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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유전자(遺傳子) 변형(變形) 농산물(農産物)에 관한 정책적(政策的) 함의(含意) (Political Implication on the Genetically Modified Crops)

  • 신용인;박인식
    • 농업과학연구
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    • 제26권2호
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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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    • 제29권3_4호
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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.
    • 충청수학회지
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    • 제32권1호
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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.