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A Study on Present Condition and Educational Improvement Plan of Building Services System (건축설비 관련 현황과 교육면에서의 개선방향 고찰)

  • Lee, Chul-Goo
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.12 no.3
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    • pp.50-57
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    • 2013
  • The education of building services field at university is not enough, although the field has become to be very important in architectural engineering. This lack of education is one of the reason that the level of domestic building services field is lower than that in developed countries. Present conditions of related laws, fields of work after graduation and education at university in building services field have been studied, and education conditions have been investigated divided into four-year architectural engineering course and five-year architecture course. Though building services field has become more important at university education, the number of credits and professor of the field is still small than other fields of architectural engineering. More practical curriculums are necessary to meet the expectation of companies, and it will be one of the method to meet it that criteria of curriculum constitution is according to ABEEK(Accreditation Board for Engineering Education of Korea) in more architectural engineering department.

Analysis of Flow Field around Multiple Fluid Spheres in the Low Knudsen Number Region (저 누드센 영역에서 다중 유체구 주위의 유동장 해석)

  • 정창훈;이규원
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.6
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    • pp.733-743
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    • 2003
  • The flow field in multiple fluid sphere systems was studied analytically. The expanded zero vorticity cell model based on Kuwabara's theory (1959) was applied and the effects of gas slippage at the collecting surface were considered. Also, the solid sphere system was extended to fluid sphere including the effects of the induced internal circulation inside the liquid droplet spheres or gas bubble systems. As a result, the obtained analytic solution was converged to the existing solutions for flow field around solid and bubble sphere systems with proper boundary conditions. Based on the resolved flow field, the terminal velocity around the collecting fluid spheres was obtained. Subsequently, this study evaluated the most general solution for flow field around the multiple fluid sphere systems. The obtained flow field in multiple fluid sphere could be used as a fundamental consideration of wet scrubber design and devices for removing particles by fluid-fluid interactions.

Separation of Colloidal Particles by Osmotic Sink Field Flow Fractionation Using UF Hollow Fiber Membranes

  • Shin, Se-Jong;Min, Byoung-Ryul;Park, Jin-Won;Ahh, Ik-Sung;Lee, Kang-Taek;Lee, Jae-Hoon
    • Korean Membrane Journal
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    • v.3 no.1
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    • pp.59-68
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    • 2001
  • Unlike existent field flow fractionation, new method, osmotic sink field flow fractionation is introduced and used ultrafiltration hollow fiber membranes as separation channel. This hollow fiber osmotic sink field flow fractionation is called HF-OSFFF. A theory that describes the retention, relaxation, resolution, plate number for the system, has been developed and experimentally verified by separation model of po1ystyrene latex beads. At external field, it is measured that radial flow rates change according to various concentrations of PEG solutions. Concentration of PEG solution vs. radial flow rate is a linear relation. For diameter distribution of unknown polymer sample, HF-OSFFF compared with the commercial capillary hydrodynamic flow fractionation (CHDF).

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Magnetic levitation force and trapped magnetic field of top-seeded melt-processed YBCO superconductors with multiseeding (다중 종자결정성장법으로 제조한 YBCO 초전도체의 자기 부상력과 포획자력)

  • Kim, Chan-Joong;Jee, Young-A;Kim, Ho-Jin;Joo, Jin-Ho;Han, Young-Hee;Kim, Sang-Jun;Hong, Gye-Won
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.358-362
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    • 1999
  • Magnetic levitation forces and trapped magnetic fields of top-seeded melt growth-processed YBCO superconductors with multiseeding were studied. The number of seeds was varied from one to six. The surface magnetic field of the prepared YBCO samples was dependent on the number of the seeds. The trapped magnetic field of the top surface decreased with increasing the number of the seed. Particularly, it drastically decreased at the YBCO grain boundary, probably due to the weak rink nature of the boundary. The magnetic levitation force also decreased with increasing the number of the seeds, similar to the variation of the surface magnetic field.

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The Design and Implementation of a Door-Lock System using a smart phone on Near Field Communication environments (비접촉식 근거리 무선통신 환경에서 스마트폰을 이용한 도어락 시스템의 설계 및 구현)

  • Kim, Dong-Hyun;Ban, Chae-Hoon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.11
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    • pp.1217-1224
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    • 2015
  • The doorlock using buttons has been widely used since it does not exploit the physical key and has much functions though it is cheap. However, the doorlock has problems where it is easy to forget the secret number since the user has to remember the number and difficult to keep secure when the one secret number has been used for a long time. In this paper, we propose the doorlock system using the near field communication. The proposed system controls the open and close of the doorlock using user data acquired by the near field communication tag, The implemented doorlock system has the benefit to control the doorlock without a secret number.

Study on Growth Responses of Soybean in Paddy Field for Establishing Environment-Friendly Cropping System (친환경 논 밭 윤환 콩 재배법 확립을 위한 논 콩 재배시 품종별 생육반응 연구)

  • Kim, Yong-Wook;Cho, Joon-Hyeong
    • Korean Journal of Organic Agriculture
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    • v.12 no.4
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    • pp.437-450
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    • 2004
  • This study was conducted with two objectives ; one was to select the suitable soybean cultivars for cultivation in paddy field and the other was to establish the environment-friendly rotational cropping system of soybean instead of rice in paddy field. In order to evaluate growth adaptation and yields, Eve soybean cultivars were cultivated in Yeoncheon, Keonggi province, with two cultivation methods such as level row and high ridge. Growth of the top plants, such as stem length, number of branches, diameter of stem, were higher in high ridge than in level row, however, the differences among the cultivars were bigger than those between the cultivation methods. Dry weight of top plant was significantly different among the cultivars during whole growth stages, however, it was higher in level row than in high ridge at V5 stage while it became higher in high ridge as growth progressed. Roots were more developed in high ridge than in level row during whole growth stages. T/R ratio in level row was higher than that in high ridge. During whole growth stages, significant differences were observed among the cultivars in growth and yields in each cultivation method and yields of Eunhakong was the highest. In results, number of nodules and T/R ratio at V5 stage, number of pods at R2 stage, and number of seeds and T/R ratio at R5 stage had highly correlated with yields, respectively.

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FORMULAS OF GALOIS ACTIONS OF SOME CLASS INVARIANTS OVER QUADRATIC NUMBER FIELDS WITH DISCRIMINANT D ≡ 1(mod 12)

  • Jeon, Daeyeol
    • Journal of the Chungcheong Mathematical Society
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    • v.22 no.4
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    • pp.799-814
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    • 2009
  • A class invariant is the value of a modular function that generates a ring class field of an imaginary quadratic number field such as the singular moduli of level 1. In this paper, using Shimura Reciprocity Law, we compute the Galois actions of some class invariants from the generalized Weber functions $\mathfrak{g}_0,\mathfrak{g}_1,\mathfrak{g}_2$ and $\mathfrak{g}_3$ over quadratic number fields with discriminant $D{\equiv}1$ (mod 12).

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GALOIS ACTIONS OF A CLASS INVARIANT OVER QUADRATIC NUMBER FIELDS WITH DISCRIMINANT D≡64(mod72)

  • Jeon, Daeyeol
    • Journal of the Chungcheong Mathematical Society
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    • v.26 no.1
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    • pp.213-219
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    • 2013
  • A class invariant is the value of a modular function that generates a ring class field of an imaginary quadratic number field such as the singular moduli of level 1. In this paper, we compute the Galois actions of a class invariant from a generalized Weber function $g_1$ over imaginary quadratic number fields with discriminant $D{\equiv}64(mod72)$.

GALOIS ACTIONS OF A CLASS INVARIANT OVER QUADRATIC NUMBER FIELDS WITH DISCRIMINANT D ≡ 21 (mod 36)

  • Jeon, Daeyeol
    • Journal of the Chungcheong Mathematical Society
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    • v.24 no.4
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    • pp.921-925
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    • 2011
  • A class invariant is the value of a modular function that generates a ring class field of an imaginary quadratic number field such as the singular moduli of level 1. In this paper, using Shimura Reciprocity Law, we compute the Galois actions of a class invariant from a generalized Weber function $g_2$ over quadratic number fields with discriminant $D{\equiv}21$ (mod 36).