• Title/Summary/Keyword: 한국 제4기학회

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A Study on the Development of Dewatering Mold Form for Performance Improvement of Concrete (콘크리트 성능개선을 위한 탈수거푸집공법의 실용화 연구)

  • Woo Kwang-Min;Lee Hak-Ki
    • Korean Journal of Construction Engineering and Management
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    • v.4 no.4 s.16
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    • pp.88-95
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    • 2003
  • Dewatering mold form get many holes on the surface to drain excessive water from combine concrete. While fiber is adhered to the forms inter surface, that makes it possible to improve concrete workability by draining excess water through the holes. We can expect the outer layer to solidify and to compact and get improvement of concretes durability. Maybe, it is valuable enough that dewatering mold form is put to practical use. On this study, the purpose is to obtain fundamental data for effective dewatering mold and properties of exposed concrete with the form, and ultimately, is to propose practical theory.

Study on the Raise and Diffusion of Understanding of the e-Learning in Universities (대학 e-러닝의 인식 제고 및 확산에 관한 연구)

  • Park, Sung-Du
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.4
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    • pp.1067-1073
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    • 2008
  • This study grasped the problem by examining the consciousness of professors about the e-Learning and reached a conclusion as follows. The understanding of the e-Learning in university should be reconsidered and diffused. To activate the e-Learning in university, the education system corresponding to course of the coming education should be introduced by hold the seminar and workshop periodically and establish vision and middle-short range policy for the e-Learning. Also, university should manage by characterizing a web-based class with the major for a learner hoping to take a cyber education course and propel contents development and interchange with a foreign university by concluding a convention for taking lectures having competitive power of an advanced country to make a worldwide university.

Studies on the Wet-injury Resistance of Wheat and Barley Varieties. IV. Effect of Excess-Moisture in the Soil on the Growth of wheat, six row and two row barley at Various Stage (맥류내습성에 관한 연구 제4보 . 맥류의 생육시기와 토양과습의 영향)

  • Hyung-Soo Suh
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.1
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    • pp.26-31
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    • 1978
  • Effect of over flooding moisture levels on the growth and yield of barley and wheat crops was determined. The marked plant height retardation of barley under over saturated moisture treatment was observed at the elongating stage and wheat at the booting stage. The elongating and tillering stage subjected to over flooding moisture level significantly reduced panicle number and grain number per panicle, and 1000-grain weight reduction at the booting stage streated with over saturated moisture level. The highest yield reduction of two row and six row barley stage, under over flooting moisture level. Soil wet resistance observed in decreasing order; wheat<six row barley<two row barley.

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Varietal Difference of Immature Spike Number and Its Relationship with Other Characters in Barley and Wheat (보리ㆍ밀 미열 이삭의 품종간 차이와 주요형질과의 상관)

  • 김흥배
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.2
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    • pp.245-249
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    • 1995
  • The number of immature spikes of barley (Hordeum vulgare L.) and wheat (Triticum aestivum L) were studied to determine if there could be existed the significant difference among 5 varieties of barley and wheat each. Heritability of 6 characters including the number of immature spikes have also calculated. Correlation between the immature spikes and 5 other characters were also investigated. There were significant difference among 5 varieties of barley and wheat in the number of immature spikes. Heritability estimated were very high in case of number of immature spikes of barley and that of wheat was high. There were highly significant correlation between the number of immature spikes of barley and number of internode and significant correlation between the number of immature spikes and flag leaf. However, in wheat no correlations were found among the 5 characters in wheat and between the number of immature spikes and number of internode were negative.

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Ignition of Fuel-rich Propellant Coated with Ignition Support Material in the Ramjet Combustor Condition (램젯 연소실 조건에서 점화보조제가 도포된 Fuel-rich 추진제의 점화)

  • Jung, Woosuk;Baek, Seungkwan;Kim, Youngil;Kwon, Taesoo;Park, Juhyun;Kwon, Sejin
    • Journal of the Korean Society of Propulsion Engineers
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    • v.21 no.4
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    • pp.79-88
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    • 2017
  • Ignition test of the fuel-rich propellant coated with ignition support material in the ramjet combustor condition was conducted. Ignition delay and flame holding was measured. Fuel grain consist of HTPB mixed with AP particle 15 wt.%, Al particle 5 wt.%. To cause the short ignition delay, ignition support consist of $NC/BKNO_3$ and composite propellant was coated to the fuel grain. Ethanol blended $H_2O_2$ gas generator control the temperature, pressure, $O_2$ concentration in the oxidizer gas in the air. Gas is supplied with mass flux of $200kg/m^2s$. Through the test ignition support operated well and ignition delay of 0.6 second and the Flame was sustained.

Kinematics and ESR Ages for Fault Gouges of the Quaternary Jingwan Fault, Dangjin, western Korea (당진 지역 제4기 진관단층의 운동 특성과 단층비지의 ESR 연령)

  • Choi, Pom-Yong;Hwang, Jae Ha;Bae, Hankyoung;Lee, Hee-Kwon;Kyung, Jai Bok
    • Journal of the Korean earth science society
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    • v.36 no.1
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    • pp.1-15
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    • 2015
  • In order to outline the kinematics and movement history of a new Quaternary fault, Jingwan Fault in Dangjin, West Korea, we analyzed the geometry of the fault zone composed of a few gouge zones, and made ESR dating for fault gouge materials. The $N55^{\circ}E$ striking Jingwan Fault is a normal fault and exhibits a gradual change in dip (gentle in the lower part, steep in the upper part), indicating a listric fault. As for the fault gouge zone, its thickness varies and reaches 2~3 cm in the lower part or between basement rocks, and 20~30 cm in the middle-upper part or between the basement and Quaternary deposit. It is observed in the latter case that more than three gouge zones develop with different colors, and branch out and re-merge, or they are partly superimposed, indicating different movement episodes. The cumulative displacement is estimated to be about 10 m using the geological cross-sections, from which it is inferred that the total length of fault may be about 2.5 km on the basis of the empirical relation between cumulative displacement and fault length. Therefore, a more study would be needed to verify the entire fault length. The results of ESR dating for three gouge samples at different spots along the fault yields ages of $651{\pm}47$, $649{\pm}96$, and $436{\pm}66ka$, indicating at least two movement episodes. Slickenlines observed on the fault planes indicate a pure dip slip (normal faulting), which suggests that the ENE-WSW trending Jingwan Fault was presumably moved under a NNW-SSE extensional environment.

Synthesis of Azelastine.HCl from 4-Chlorophenyl Acetic Acid (4-염화페닐 아세트산을 이용한 염산 아젤라스틴의 합성)

  • Ji, Hyun;Jeong, Noh-Hee
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.3
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    • pp.429-434
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    • 2012
  • A kind of Antihistamines, Azelastine HCl which known as modern H1-blockers, was synthesized by four step process using phthalic anhydride, 4-chlorophenylacetic acid, hydrazine 2HCl. The first step was the reaction of removing carboxyl group and hydroxyl group and the second step was saponification of 3-(4-chlorobenzylidene)phthalide. The third step was the nucleophilic addition reactions of primary amines and the fourth step was addition reaction of N-methyl-1-aza-bicyclo[3,2,0]heptane to 4-(4-chlorobenzyl)-1-(2H)phthalazinone. As a result, product was analyzed by FT-IR and $^1H$-NMR and could be obtained with a yield of 80%.

Characteristics of p-Xylene Adsorption using Functionalized Mesoporous Silica (관능기화 메조포러스 실리카를 이용한 파라자일렌 흡착 특성)

  • Kim, Sang-Hyoun;Park, Jonghoon;Kang, Seok-Tae;Chung, Jae-Woo;Kim, Soo-Hong;Cho, Yunchul;Lee, Chae-Young
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.6
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    • pp.27-31
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    • 2012
  • This study was designed to examine the feasibility of functionalized mesoporous silica as the adsorbent for benzene, toluene, ethylbenzene, and xylene isomers (BTEX) in groundwater. p-Xylene was used as the model compound of BTEX. A series of functionalized mesoporous silica with MCM-41 type of structure was synthesized using a co-condensation method. Monoamine, triamine, nitrile, phenyl, and octyl groups were functionalized to the mesoporous silica structure. Adsorption sites for p-Xylene in a functionalized mesoporous silica were Si-O-Si covalent bond, the surfactant, and the functional group. Octyl-functionalized mesoporous silica with stearyltrimethylammonium chloride as a surfactant showed the highest adsorption ability. The maximum xylene adsorption capacity of the octyl-functionalized mesoporous silica with stearyltrimethylammonium chloride based on Langmuir model was 4.17 mmol/g on $20^{\circ}C$, which was 2.9 times higher than that of MCM-41.

Development of Reservoir Operation Model using Simulation Technique in Flood Season(II) (모의기법에 의한 홍수기 저수지 운영 모형 개발(II))

  • Sing, Yong-Lo;Maeng, Sung-Jin;Ko, Ick-Hwan;Lee, Hwan-Ki
    • Journal of Korea Water Resources Association
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    • v.35 no.6
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    • pp.797-805
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    • 2002
  • The EV ROM, a joint reservoir operation model for flood control that accounts for the downstream flow condition, has been introduced in the preceding article (Shin et al, 2000). A joint reservoir operation model computer program for the Geum river basin, developed by FORTRAN Power Station 4.0 using the EV ROM, is hereby presented. Three case studies of flood control by joint operation of the Yongdam and Daechung Multipurpose Dams in the Geum river basin revealed that the performance of the EV ROM was superior to the existing Rigid ROM and Technical ROM. This is because the EV ROM can account for the downstream flow condition as well as the upstream inflow and the reservoir water level. In order to apply for various floods events in the future, consistent improvement of the developed EV ROM and efforts for more accurate rainfall prediction are required.

Electrospray ionization tandem mass fragmentation pattern of camostat and its degradation product, 4-(4-guanidinobenzoyloxy)phenylacetic acid (Camostat 및 분해산물 4-(4-guanidinobenzoyloxy)phenylacetic acid의 전자분무 이온화 텐덤 질량 fragmentation 패턴)

  • Kwon, Soon-Ho;Shin, Hye-Jin;Park, Ji-Myeong;Lee, Kyoung-Ryul;Kim, Young-Jin;Lee, Sang-Hoo
    • Analytical Science and Technology
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    • v.24 no.2
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    • pp.78-84
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    • 2011
  • The fragmentation patterns of a serine protease inhibitor, camostat, and its degradation product, 4-(4-guanidinobenzoyloxy)phenylacetic acid (GBPA), were for the first time investigated by a triple quadrupole tandem mass spectrometry equipped with an electrospray source (ESI-MS/MS) in positive and/or negative ion mode under collision-induced dissociation (CID). The positive CID spectrum of camostat showed distinctly that the single bond (C-O) cleavage between carbonyl group and oxygen atom of the ester bonds of the compound favorably occurred and then the loss of N,N-dimethylcarbamoylmethyl group was more susceptible than that of guanidine moiety. In the positive ion CID spectrum of GBPA, the initial cleavage between the carbonyl group and oxygen atom of 4-guanidinobenzoyloxy group also occurred, yielding the most abundant fragment ion at m/z 145. On the other hand, the negative CID spectrum of GBPA characteristically showed the occurrence of the most abundant peak at m/z 226 resulting from the sequential neutral losses of $CO_2$ and HN=C=NH from the parent ion at m/z 312.