• Title/Summary/Keyword: Phases and patterns

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The influence of the powder sintering the 2nd sintering and the grinding time on superconducting properties of Bi(Pb)SrCaCuO superconductor (Bi(Pb)SrCaCuO 초전도체의 초전도특성에 미치는 분말소결 및 2차성형, 분쇄시간에 따른 영향)

  • 신철기;김영천
    • Electrical & Electronic Materials
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    • v.7 no.4
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    • pp.306-311
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    • 1994
  • In this study, the influence of the powder sintering, the 2nd sinteiing and the grinding time on the Superconducting properties in the Bi(Pb)SiCaCuO Superconductor has been studied. From the analysis of SEM and XRD patterns, it was known that the sample prepared by the process of powder sintering has a porous microstructure with the critical temperature(Tc) below 77K, while the sample prepared by the 2nd sintering has a highly oriented microstructure with the Tc above 100K. The Critical Current Density(Jc) of the sample prepared by the 2nd sintering was better than the sample prepared by the process of powder sinteiing, but it's Jc, was low in practical use. Also, the effect of grinding time from 0[min] to 120[min] was investigated. As the grinding time is increased, the samples degraded from high-Tc phase to low-Tc phase and nonsuperconducting phases.

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Diopside DSD (crystal size distribution) in the Contact Metamorphic Aureole (Hwanggangni Formation) near the Daeyasan Granite Goesan, Korea (괴산지역 대야산 화강암체 주변 접촉변성대(황강리층)에서의 투휘석 결정 크기분포)

  • Kim, Sangmyung;Kim, Hyung-Shik
    • The Journal of the Petrological Society of Korea
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    • v.5 no.2
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    • pp.161-167
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    • 1996
  • The CSD (crystal size distribution) of diopside crystals in the calc-silicate hornfels of the Hwanggangni Formation intruded by the Cretaceous Daeyasan granite shows the patterns of continuous nucleation and growth. There is correlation between the distance from the intrusion contact and the slopes from the linear part of log(population density) vs. size diagrams. In the log(population density) vs. size diagrams of the samples systematically collected from the intrusion contact, two different groups are recognized; the slopes for the samples near the intrusion contact (horizontal distance from the contact less than 50m) are gentler (1500$cm^{-1}$) than those for the samples away from the intrusion contact (2500$cm^{-1}$, distance from the contact greater than 100 m). These differences may reflect the differences in growth rates and crystallization time, or the differences in diopside-forming reactions. All of the log(population density) vs. size diagrams show depletion of smaller crystals. The observed depletion may be due to Ostwald ripening or the changes in nucleation rates as the reactant phases diminishes. Similar grouping is also possible for the observed degree of depletion of smaller crystals; the depletion decreases with increasing distance from the intrusion contact, suggesting temperature-dependent rates of Ostwald ripening.

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A Study on the Reading Efficiency of Comics (만화의 독서 효용성에 관한 연구)

  • Ryu, Ban-Dee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.22 no.2
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    • pp.123-139
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    • 2011
  • This study focuses on how the characteristics of the comics make the medium a useful reading material. To highlight how the characteristics of comics enhance the media's capacity for reading, this study analyzed several patterns of adaptation from a comic to other media. The usefulness of comics as a reading text can be summarized as follows: First, comics have alternate phases of immersion and concentration. Second, comics provide the whole view as well as speed. These two factors make the comics as an interesting reading material.

Applying Practice Patterns to Improve Source Code Quality of Embedded Software (임베디드 소프트웨어의 소스 코드 품질 향상을 위한 Practice Patterns의 적용)

  • Hong Jang-Eui
    • The KIPS Transactions:PartA
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    • v.12A no.7 s.97
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    • pp.589-596
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    • 2005
  • Source code quality is very Important that software embedded into product is difficult to change. In order to improve source code quality, it should be considered the quality of analysis and design models as well as the quality of source code. In this paper, we suggest 'Practice Pattern' as one of practical techniques to improve embedded software source code quality. Practice pattern is a procedural pattern to guide modeling and coding activities in software development phases. We believe that applying our pattern provides the improvement of optimum performance, modularization, and portability for embedded software source code.

Electrical Properties of PZT/BT Mulitilayered Films (PZT/BT 박막의 전기적 특성)

  • Lee, Sang-Heon;Nam, Sung-Pil;Lee, Young-Hie;Park, Jae-Jun
    • Proceedings of the KIEE Conference
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    • 2005.11a
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    • pp.189-190
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    • 2005
  • Ploycrystalline $Pb(Zr_{0.5},Ti_{0.5))O_3$ and $BaTiO_3$ powder were prepared by sol-gel process. The alumina substrate were sintered at $1400^{\circ}C$ with bottom electrode of Pt for 2 hours. The Pb(Zr0.5,Ti0.5)O3 / BaTiO3 multilayered thick films with laminating times were fabricated on alumina substrate by screening printing method. The obtained thick films were sintered at $800^{\circ}C$ with upper electrode of Ag paste for 1 hour. Structural properties of Pb(Zr0.5,Ti0.5)O3 / BaTiO3 multilayered thick films were investigated. As a result of the Differential Thermal Analysis(DTA) of Pb(Zr0.5,Ti0.5)O3, exothermic peak was observed at around 650 $^{\circ}C$. The X-ray diffraction (XRD) patterns indicated that BaTiO3 and Pb(Zr0.5,Ti0.5)O3 phases and porosities were formed in the interface of Pb(Zr0.5,Ti0.5)O3 / BaTiO3multilayered thick films.

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Structural Properties of PZT BT Mulitilayered Films (PZT BT 이종 박막의 구조적 특성)

  • Lee, Sang-Heon;Lim, Sung-Soo;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.1960-1961
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    • 2005
  • Ploycrystalline $Pb(Zr_{0.5},Ti_{0.5})O_3$ and $BaTiO_3$ powder were prepared by sol-gel process. The alumina substrate were sintered at $1400^{\circ}C$ with bottom electrode of Pt for 2 hours. The Pb(Zr0.5, Ti0.5)O3/BaTiO3 multilayered thick films with laminating times were fabricated on alumina substrate by screening printing method. The obtained thick films were sintered at $800^{\circ}C$ with upper electrode of Ag paste for 1 hour, Structural properties of Pb(Zr0.5,Ti0.5)O3/BaTiO3 multilayered thick films were investigated. As a result of the Differential Thermal Analysis(DTA) of Pb(Zr0.5,Ti0.5)O3, exothermic peak was observed at around $650^{\circ}C$. The X-ray diffraction (XRD) patterns indicated that BaTiO3 and Pb(Zr0.5,Ti0.5)O3 phases and porosities were formed in the interface of Pb(Zr0.5,Ti0.5)O3 / EaTiO3 multilayered thick films.

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Microwave Dielectric Properties of 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ Ceramics (0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ 세라믹스의 마이크로파 유전특성)

  • Kim, Jae-Sik;Choi, Eui-Sun;Lim, Sung-Soo;Chung, Jang-Ho;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1491-1493
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    • 2002
  • The 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ ceramics were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature by XRD. According to the X-ray diffraction patterns, major phases of the 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ ceramics were coexisted. Also the secondary phase of Mg$Ti_2O_5$, Ba$Mg_6Ti_6O_{19}$ and the unreacted $TiO_2$ phase were existed. In the case of 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ ceramics sintered $1350^{\circ}C$, dielectric constant, quality factor and temperature coefficient of resonant frequency were 33.7, 54,900GHz, -12.5ppm/$^{\circ}C$, respectively.

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Comparative study on patterns and symptoms of disharmony(病機病症) between the internal organs(藏府) and external bodily form(身形) (藏府와 身形의 病機 및 病症에 대한 比較考察)

  • Baek, Sang-Ryong
    • Journal of Korean Medical classics
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    • v.13 no.2 s.17
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    • pp.21-21
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    • 2000
  • All living things including human being consist of soul(spirit) and body. Soul is the root of a life and body frames it. I wrote this paper to tell how internal injury due to endogenous etiological factors and affection due to exegenous pathogenic factors, affect the internal organs and the external bodily from. This paper begins with description of the patterns of disharmony of the internal organs. General disorders of each Five-Jang(五藏) an be classified into two types of soul and body. The Liver and the Heart which lead changing to Yang(陽) of vital energy, have close relationship with spiritual symptoms because spirit is related to Yang. The Lung, Kidneys, the Spleen which lead changing to m(陰) of vital energy, mainly connected with physical disorders because body is relatively close to m. The Five-Jang are ruled by the Five-Phases(五行) system and cause troubles with Oche(五體) and the nine body orifice. Otherwise the main function of the Six-Bu(六府) is to receive food, absorb the usuable portions, and transmit and excrete waste. Therefore they can cause such problems as abdominal pain, distention, difficulty in urination, and constipation. The spleen is responsible for sending Grain-Ki)穀氣) 내 that is closely connected with the six-Bu. The Gall bladder takes care of control of giving out spirit. That's why it presents many symptoms related to the spirit that is ruled by the Five-Jang. Patterns of disharmony of external bodily form is influenced by the state of Maridians. Bodily forms get divided into many parts by the function of six-meridians(六經) to which they belong. Six-meridians have their own function related to excretion, related to excretion, retention, and balance(開闔樞). If local bodily froms get affected by pernicious influences, the Meridians to which they are attached will lose harmony and connot fulfil their own functions. Because the meridian symtem unifies all parts of the body, the whole body will be under the influence of the affection although local parts of the bodily forms get affected. Therefore the symptoms of disharmony should be considered in a synthetic view. There are however, also cases which should be focused on the very meridian channels affected. Disorder within a Meridian generates derangement in the pathway make it not to benefit the muscles and skin belong to it. Because the meridians connect the interior organs with the exterior bodily form, they are influenced by each other.

Comparative study on patterns and symptoms of disharmony(病機病症) between the internal organs(藏府) and external bodily form(身形) (장부(藏府)와 신형(身形)의 병기(病機) 및 병증(病症)에 대한 비교고찰(比較考察))

  • Baek, Sang-Ryong
    • Journal of Korean Medical classics
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    • v.13 no.2 s.17
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    • pp.22-42
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    • 2000
  • All living things including human being consist of soul(spirit) and body. Soul is the root of a life and body frames it. I wrote this paper to tell how internal injury due to endogenous etiological factors and affection due to exogenous pathogenic factors, affect the internal organs and the external bodily from. This paper begins with description of the patterns of disharmony of the internal organs. General disorders of each Five-Jang(五藏) an be classified into two types of soul and body. The Liver and the Heart which lead changing to Yang(陽) of vital energy, have close relationship with spiritual symptoms because spirit is related to Yang. The Lung, Kidneys, the Spleen which lead changing to m(陰) of vital energy, mainly connected with physical disorders because body is relatively close to m. The Five-Jang are ruled by the Five-Phases(五行) system and cause troubles with Oche(五體) and the nine body orifice. Otherwise the main function of the Six-Bu(六府) is to receive food, absorb the usable portions, and transmit and excrete waste. Therefore they can cause such problems as abdominal pain, distention, difficulty in urination, and constipation. The spleen is responsible for sending Grain-Ki(穀氣) so that is closely connected with the six-Bu. The Gall bladder takes care of control of giving out spirit. That's why it presents many symptoms related to the spirit that is ruled by the Five-Jang. Patterns of disharmony of external bodily form is influenced by the state of Meridians. Bodily forms get divided into many parts by the function of six-meridians(六經) to which they belong. Six-meridians have their own function related to excretion, related to excretion, retention, and balance(開闔樞). If local bodily forms get affected by pernicious influences, the Meridians to which they are attached will lose harmony and cannot fulfil their own functions. Because the meridian system unifies all parts of the body, the whole body will be under the influence of the affection although local parts of the bodily forms get affected. Therefore the symptoms of disharmony should be considered in a synthetic view. There are however, also cases which should be focused on the very meridian channels affected. Disorder within a Meridian generates derangement in the pathway make it not to benefit the muscles and skin belong to it. Because the meridians connect the interior organs with the exterior bodily form, they are influenced by each other.

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The Study on the Crystal Growing of Mn-Zn Ferrite Single Crystals by Floating Zone Method (Floating Zone법에 의한 Mn-Zn Ferrite 단결정성장에 관한 연구)

  • 정재우;오근호
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.2 no.1
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    • pp.10-19
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    • 1992
  • Mn - Zn Ferrite has physical properties of the high initial permeability, saturation magnetic flux density, and low loss factor as a representative magnetic material of soft ferrites, in addition the mechanical property is excellent as a single crystal. Therefore it is important electronic components and used for VTR Head. Mn - Zn Ferrite single crystals with the diameter 8mm were grown in atmosphere mixed with $O_2$ and Ar gas by the Floating Zone(FZ) method that impurities can not be incorporated to the crystals because of not-using the crucible to put in the melt, and the sharp temperature gradient results from making a focus at one point utilizing the infrared ray emitted from the halogen lamp as a heat source. During the crystal growing, the highest temperature of melting area was maintained to be $1650^{\circ}C$, growth rate and rotation rate were 10 mm/hr, 20 rpm respectively. The phases and the growth directions of crystals were determined from the analysis of X RD patterns, Laue, TEM diffraction patterns and etch pit shapes were observed by the optical microscope through the chemical etching. The corelation of optimum conditions for acquiring the better crystals was found out with the growth rate, the length and diameter of melt at the interface according to the diameter of feed rod, and the patterns of growing interface also studied.

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