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A Study on a Morphological Identification of Cnidium Rhizome and Ligusticum Rhizome (천궁(川芎)의 형태(形態)에 관한 연구(硏究))

  • Choi, Jeong-Kook;Lim, Deog-Bin;Lee, Young-Jong
    • The Korea Journal of Herbology
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    • v.20 no.4
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    • pp.95-101
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    • 2005
  • Objectives : In order to distinguish Cnidii Rhizoma and Ligustici Chuanxiong Rhizoma (cultivated in Korea and China), their external and internal states were observed via microscopic examination. Methods : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and then observed and photographed by olymphus-BHT. Results : Cnidii Rhizoma, Ligustici Chuanxiong Rhizoma (from Korea), and Ligustici Chuanxiong Rhizoma (from China) all demonstrated similar patterns as following : 1. external form 1) showing irregular nodular form with $2{\sim}7cm$ diameter. 2) having several trochites in parallel, and nodulose root trace on surface. 3) in addition to yellow-white or yellow-gray intersections, yellow-brown oil sacs were distributed, with cambium resembling a form of annulus. 2. internal form 1) its root and rhizome is composed of 10 layers of cork, with narrow cortical layers. 2) its phloem is wide, and oval light yellow-brown oil sacs are distributed around. The closer to the cambium, the smaller it is. 3) cambium is a form of a wave-like ring or an irregular polygon. 4) xylem and vessel are rare, most of which are arranged in a 'V' format, and sometimes xylem fiber is found. 5) pith is composed of parenchymatous cell, and parenchyma is full of starch grains. Conclusions : In conclusion, C officinale, L. chuanxiong (from Korea), and L. chuanxiong (from China) have rhizomes in a similar form with no special difference. Therefore, it is concluded that C. officinale, L. chuanxiong (from Korea), and L. chuanxiong (from China) are categorized into the same species.

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Electron Microscopic Studies on Adenohypophysis of Korean Native Goat (한국재래산양(韓國在來山羊)의 선하수체(腺下垂體) 분필세포(分泌細胞)에 관(關)한 전자현미경적(電子顯微鏡的) 연구(硏究))

  • Lee, I.S.;Lee, H.S.
    • Applied Microscopy
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    • v.14 no.2
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    • pp.52-65
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    • 1984
  • The ultrastructure of the pars distalis of the adenohypophysis was studied in the female Korean native goat ($10{\sim}16kg$, B.W.) by electron microscopy. Six granular cells and one agranular cell were recognized according to the characteristic patterns of secretory granules and cell organelles. Type I cells were. large, round or oval and contained the largest granules of 290 to 490 nm in diameter, Their endoplasmic reticula were well developed and packed with parallel lamellae close to nuclear membrane. Type II cells were elongate or polygonal. They contained granules of 220 to 390 nm in diameter and well developed Golgi complex. Type III cells were round, oval or angular and contained granules of 150 to 300 nm in diameter. Their endoplasmic reticula were coarsely scattered among the granules and provided an intracellular compartment for segregation in groups. Type IV cells were oval or round and contained granules of 120 to 280 nm in diameter. Their endoplasmic reticula were arranged at one pole of cytoplasm. Type V cells were round or polygonal and contained small granules of 110 to 140 nm in diameter Their endoplasmic reticula were packed with regularly parallel lamellae. Type VI cells were stellate and irregular in shape and had cytoplasmic processes projecting between the neighboring cells. Their granules were less than 130 nm in diameter, the smallest among the cells of the pars distalis. Agranular cells had no granules or a few, if any. They were stellate or irregular in shape.

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Endowment of Traditionality to the New Style Taekwondo Uniform and a Proposal of Its Design Modification (신형 태권도 공인도복의 전통성 제언 및 디자인 수정 제안)

  • Choi, Yeon-Woo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.38 no.1
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    • pp.19-32
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    • 2014
  • The Taekwondo uniform has remained consistent since it was officially designed in a V-neck form in 1976. Taekwondo is a martial art that emphasizes social etiquette; therefore, it is necessary to dress in a uniform that reflects Korean traditions and ancient oriental philosophy. However, the current official uniform has limitations in endowing traditionality and many usability problems. Thus, recognizing the problems raised with the uniform, the Kukkiwon (World Taekwondo Headquarters) developed a new style official uniform in 2011. This study is to endow traditional meaning to a new style uniform and proposes some design modifications that can convey a more traditional adequacy. The development of the new official uniform began with a specific plan for change from the existing uniform, this study as subsequent work is significant in that its endowment of symbolism and modification proposal is for the actual execution and global dissemination of traditional Taekwondo culture. The results of this study are as follows. First, we can endow Korea's traditional historicity and symbolism to the new uniform in form and colors. All contents of the design (in which the front side is open, the top is adjusted rightward, the rear length is shorter than the front length, comfort provided by side vents, dual collars for children's uniforms, and a belt) are adapted from the Korean traditional costume. Consequently, historicity can be endowed to the uniform. It is also confirmed that the traditional oriental philosophy including heaven and earth (天地), Yin-Yang (陰陽), and Five Elements (五行) can be endowed in the use of colors. Second, in order to project deeper historicity and symbolism to the form of the new uniform, this study proposes design modifications based on the selection as an item of Simui (深衣), a type of traditional clothing that contains a high symbolism similar to the Taekwondo uniform. It proposes giving shape to the practice of manners, the righteous life, and the straightforward mind by modifying the design of the uniform in the fish belly part of the sleeves, collars, back stitches, and side seams.

Natural Indigo Dyeing by Using Glucose Reduction (포도당 환원을 이용한 천연 인디고 염색)

  • Shin, Youn-Sook;Cho, A-Rang;Yoo, Dong-Il
    • Textile Coloration and Finishing
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    • v.21 no.3
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    • pp.10-18
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    • 2009
  • Dyeing process of the natural indigo powder onto ramie and silk fabrics was investigated by using glucose and calcium hydroxide as a reducing system. Effect of reduction and dyeing conditions such as temperature and time of reduction/dyeing, and concentrations of glucose and calcium hydroxide on the dyeing process were explored. Indigo powder was obtained by drying the conventional niram paste in an oven at $50^{\circ}C$. Color strength of the dyed fabrics was evaluated by K/S value measured at the wavelength of maximum absorption(${\lamda}$max). Munsell color coordinates(H V/C) were used to compare fabric colors of ramie and silk. Ramie fabric showed purple-blue color for all the temperature and time. On the contrary, silk fabric showed wide range of color including brown, brown-green, green at the different temperature. With the increase of K/S value, the coordinate of value(lightness) decreased for both of ramie and silk fabrics. The coordinate of hue(shade) changed drastically with the increase of K/S value for silk fabric, compared with that of ramie fabric which showed nearly constant value at the whole range of K/S value. Optimum concentrations of calcium hydroxide were for 6 g/L for ramie and 4 g/L for silk at $60^{\circ}C$ and 50 min. K/S value increased with the indigo concentration. Maximum K/S value was shown at $10{\sim}12$ g/L of glucose concentration. For both of ramie and silk fabrics, the colorfastness of washing and light was lower than that of rubbing. All the colorfastness values were improved with the increase of color strength.

Effect of Water on the Kinetics of Nitric Oxides Reduction by Ammonia over V-based Catalyst (바나듐계 촉매상에서 암모니아를 이용한 질소산화물의 환원반응속도에 수분이 미치는 영향에 관한 연구)

  • Kim, Young-Deuk;Jeong, Soo-Jin;Kim, Woo-Seung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.6
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    • pp.73-82
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    • 2012
  • The main and side reactions of the three selective catalytic reduction (SCR) reactions with ammonia over a vanadium-based catalyst have been investigated using synthetic gas mixtures in the temperature range of $170{\sim}590^{\circ}C$. The three SCR reactions are standard SCR with pure NO, fast SCR with an equimolar mixture of NO and $NO_2$, and $NO_2$ SCR with pure $NO_2$. Vanadium based catalyst has no significant activity in NO oxidation to $NO_2$, while it has high activity for $NO_2$ decomposition at high temperatures. The selective catalytic oxidation of ammonia and the formation of nitrous oxide compete with the SCR reactions at the high temperatures. Water strongly inhibits the selective catalytic oxidation of ammonia and the formation of nitrous oxide, thus increasing the selectivity of the SCR reactions. However, the presence of water inhibits the SCR activity, most pronounced at low temperatures. In this study, the experimental results are analyzed by means of a dynamic one-dimensional isothermal heterogeneous plug-flow reactor (PFR) model according to the Eley-Rideal mechanism.

Study on Parameter Optimization in Daegok & Sayun Dam Basins Using HEC-HMS (대곡.사연댐 유역의 HEC-HMS를 이용한 매개변수 최적화 연구)

  • Yoon, Guk-Hui;Park, Myung-Ky;Choi, Byung-Man;Kim, Yung-Jin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1103-1107
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    • 2009
  • 최근 기상이변에 따른 국지성 호우 등으로 인하여 지역별로 홍수량 차이가 많이 나고 있는 상황으로 유역내 중요시설물 및 인명의 보호를 위해서는 유역의 특성을 정확하게 반영한 홍수분석이 필수적인 실정이다. 유역 주요지점의 정확한 홍수량을 산정하기 위해서는 지역특성이 반영된 호우를 선정하고, 유출모의를 위한 유역특성이 잘 구현되어야 한다. 이를 위해서는 홍수량산정에 영향을 주는 매개변수의 정확한 산정이 필요하며 본 연구에서는 미공병단(US Army Corps)에서 개발하여 배포한 차세대 프로그램인 HEC-HMS(v3.3)를 이용하여 집중시간, 저류상수, Curved Number, 감수상수, 초기손실, 초기기저유량, Threshold 등 7가지 매개변수에 대한 최적화를 수행하였다. 종래에는 첨두홍수량을 중시하여 집중시간과 저류상수는 최적화하고 나머지 변수들은 실측치 및 계산값을 적용하였으나, 금번 연구에서는 첨두홍수량 및 총유출량 모두 관측값에 최대한 일치하도록 7가지 매개변수를 최적화하는 방안 및 최적화시 초기값 선정이 매개변수 최적화에 미치는 영향을 연구하였다. 매개변수 최적화 순서는 먼저 전체적인 평균유출량 또는 평균유출고가 실측치와 모의치 간에 일치하도록 CN, RC를 보정하고 다음 단계로 첨두발생시간이 일치하도록 Tc, K를 보정하고, 마지막으로 홍수 수문곡선의 형태를 결정하는 나머지 매개변수를 조정하여 전체적인 수문곡선의 형태와 첨두홍수량이 일치하도록 수행하였으며, Tc, K, CN 등의 중요 매개변수는 신뢰구간(계산치의 0.8${\sim}$1.2)을 설정하여 목적함수의 수렴을 유도하였다. 위를 이용하여 수렴된 매개변수들로 강우-유출 모의를 분석한 결과를 기존 홍수사상과 비교한 결과 상당히 근접한 결과를 도출할 수 있어, 매개변수는 7가지 모두에 대한 최적화를 가능한 것으로 연구되었으나 목적함수들의 수렴되는 과정에 대해서는 좀 더 심도있는 고찰이 필요할 것으로 판단된다.

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Effects of Different Precursors on the Surface Mn Species Over $MnO_x/TiO_2$ for Low-temperature SCR of NOx with $NH_3$

  • Kim, Jang-Hoon;Yoon, Sang-Hyun;Lee, Hee-Soo
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.10a
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    • pp.29.1-29.1
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    • 2011
  • The selective catalytic reduction (SCR) of $MnO_x$ with $NH_3$ is an effective method for the removal of $MnO_x$ from stationary system. The typical catalyst for this method is $V_2O_5-WO_3(MoO_3)/TiO_2$, caused by the high activity and stability. However, This catalyst is active within $300{\sim}400^{\circ}C$ and occurs the pore plugging from the deposition of ammonium sulfate salts on the catalysts surface. It needs to locate the SCR unit after the desulfurizer and electrostatic precipitator without reheating of the flue gas as well as deposition of dust on the catalyst. The manganese oxides supported on titania catalysts have attracted interest because of its high SCR activity at low temperature. The catalytic activity of $MnO_x/TiO_2$ SCR catalyst with different manganese precursors have investigated for low-temperature SCR in terms of structural, morphological, and physico-chemical analyses. The $MnO_x/TiO_2$ were prepared from three different precursors such as manganese nitrate, manganese acetate (II), and manganese acetate (III) by the sol-gel method and then it calcinated at $500^{\circ}C$ for 2 hr. The structural analysis was carried out to identify the phase transition and the change intensity of catalytic activity by various manganese precursors was analyzed by FT-IR and Raman spectroscopy. These different precursors also led to various surface Mn concentrations indicated by SEM. The Mn acetate (III) tends to be more suppressive the crystalline phase (rutile), and it has not only smaller particle size, but also better distributed than the others. It was confirmed that the catalytic activity of MA (III)-$MnO_x/TiO_2$ was the highest among them.

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Physical and Microwave Dielectric Properties of the MgO-SiO2 System

  • Yeon, Deuk-Ho;Han, Chan-Su;Key, Sung-Hoon;Kim, Hyo-Eun;Kang, Jong-Yun;Cho, Yong-Soo
    • Korean Journal of Materials Research
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    • v.19 no.10
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    • pp.550-554
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    • 2009
  • Unreported dielectrics based on the binary system of MgO-SiO$_2$ were investigated as potential candidates for microwave dielectric applications, particularly those demanding a high fired density and high quality factors. Extensive dielectric compositions having different molar ratios of MgO to SiO$_2$, such as 2:1, 3:1, 4:1, and 5:1, were prepared by conventional solid state reactions between MgO and SiO$_2$. 1 mol% of V$_2$O$_5$ was added to aid sintering for improved densification. The dielectric compositions were found to consist of two distinguishable phases of Mg$_2$SiO$_4$ and MgO beyond the 2:1 compositional ratio, which determined the final physical and dielectric properties of the corresponding composite samples. The increase of the ratio of MgO to SiO$_2$ tended to improve fired density and quality factor (Q) without increasing grain size. As a promising composition, the 5MgO.SiO$_2$ sample sintered at 1400 $^{\circ}C$ exhibited a low dielectric constant of 7.9 and a high Q $\times$ f (frequency) value of $\sim$99,600 at 13.7 GHz.

DESIGN OF HIGH SENSITIVE SP ACEBORNE MICROWAVE RADIOMETER DREAM ON STSAT-2

  • Kim Sung-Hyun;Lee Ho-Jin;Yun Seok-Hun;Chae Chun-Sik;Park Hyuk;Kim Yong-Hoon;Park Jeong-oh;Sim Eun-Sup;Zhang De-Hai;Jiang Jing-Shan
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.526-529
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    • 2005
  • Dual-channel Radiometers for Earth and Atmosphere Monitoring (DREAM) is the Korean first spaceborne microwave radiometer which is the main payload of Science and Technology SATellite-2 (STSAT-2). STSAT-2 will be launched by Korea Space Launch Vehicle-l (KSL V-I) at NARO Space Center in Korea in 2007. DREAM is a two-channel, total power microwave radiometer with the center frequencies of 23.8 GHz and 37 GHz. The spaceborne radiometer is composed of an antenna unit, a receiver unit, and a data acquisition/processing unit. The bandwidths of radiometer are 600 MHz at 23.8 GHz and 1000 MHz at 37 GHz. The integration time of two channels is 200 rns. The sensitivity of DREAM is less than 0.5 K. This paper presents the required performance and system design of DREAM in detail.

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Simulation of Neutron irradiation Corrosion of Zr-4 Alloy Inside Water Pressure reactors by Ion Bombardment

  • Bai, X.D.;Wang, S.G.;Xu, J.;Chen, H.M.;Fan, Y.D.
    • Journal of the Korean Vacuum Society
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    • v.6 no.S1
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    • pp.96-109
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    • 1997
  • In order to simulate the corrosion behavior of Zr-4 alloy in pressurized water reactors it was implanted (or bombarded) with 190ke V $Zr^+\; and \;Ar^+$ ions at liquid nitrogen temperature and room temperature respectively up to a dose of $5times10^{15} \sim 8\times10^{16} \textrm{ions/cm}^2$ The oxidation behavior and electrochemical vehavior were studied on implanted and unimplanted samples. The oxidation kinetics of the experimental samples were measured in pure oxygen at 923K and 133.3Pa. The corrosion parameters were measured by anodic polarization methods using a princeton Applied Research Model 350 corrosion measurement system. Auger Electron Spectroscopy (AES) and X-ray Photoelectric Spectroscopy (XPS) were employed to investigate the distribution and the ion valence of oxygen and zirconium ions inside the oxide films before and after implantation. it was found tat: 1) the $Zr^+$ ion implantation (or bombardment) enhanced the oxidation of Zircaloy-4 and resulted in that the oxidation weight gain of the samples at a dose of $8times10^{16}\textrm{ions/cm}^2$ was 4 times greater than that of the unimplantation ones;2) the valence of zirconium ion in the oxide films was classified as $Zr^0,Zr^+,Zr^{2+},Zr^{3+}\; and \;Zr^{4+}$ and the higher vlence of zirconium ion increased after the bombardment ; 3) the anodic passivation current density is about 2 ~ 3 times that of the unimplanted samples; 4) the implantation damage function of the effect of ion implantation on corrosion resistance of Zr-4 alloy was established.

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