• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.9
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• pp.464-469
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• 2004

The leakage current of transmission insulators contaminated with salt, clay, and kaolin was examined in the Gochang's Long Periods Testing Center. The Insulators were artificially contaminated and estimated with the method of equivalent salt deposit density(ESDD). The artificially contaminated insulators were installed with the same condition as in the real transmission power line and applied with 154 (kV). The leakage current of the artificially contaminated insulators was measured with environment conditions, such as temperature and humidity by the a automatic leakage current detecting system. The leakage current of heavily contaminated insulator was abruptly increased above 72［%］ of humidity, even though the leakage current was similar between the contaminated and non-contaminated insulators below 72［%］ of humidity. Also, it was found that the humidity was much more important than the temperature in the leakage current of transmission insulators. The leakage current of contaminated insulator was decreased when it was plenty of rainfall, resulting from natural washing.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.290-293
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• 2000

After kaolin clay was compulsorily contaminated with Co$^{2+}$ion, the remediation characteristics by electrokinetic method were analyzed. Ethanoic buffer was injected in the soil column and $CH_3$COOH was continuously inputted in cathode reservoir to restrain the pH elevation. Since pH of the cathode side of the soil column was 4.0 at initial and was restrained by 6.5 at 43.6 hours, Precipitation, Co(OH)$_2$, was not formed in the column. Effluent rate increased with time passage and remediation in the column in initial time was mainly controlled by ion migration. 13.1% of total in the soil column was remediated in 10 hours, and the 6.8% of total in 20.8 hours, and the 71.7% of total in 43.6 hours, and the 94.6% of total in 43.6 hours. Meanwhile, the residual concentrations in the column calculated by the developed model were similar to those by experiment.t.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.10a
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• pp.23-27
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• 1999

After kaolin clay was compulsorily contaminated by Sr$^{2+}$ solution, the remediation characteristics by electrokinetic method were analyzed. Meanwhile, the numerical code for analysis of electrokinetic migration was developed for modelling of the soil remediation. Experimental results are as follows After 3 day remidiation under 40 voltage, the front part of experimental cell was almost decontaminated, but the behind part didn't almost be decontaminated. Accordingly, the total remediation ratio of Sr$^{2+}$ from cell soil was about 42.6 %. Also, the total Sr$^{2+}$ remediation ratio from cell soil was about 84.8 % after 6 days, and about 97.1 % after 7 days. Meanwhile, the values calculated by the developed code almost agreed with experimental values.ues.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.3
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• pp.32-38
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• 2000

This study was carried out to determine the effect of the type of plastic pigment on the coat-ing structure and printability of coated paper. Three kinds of plastic pigments(solid-bead type binder type and hollow type) were used for hti purpose. IN this research it was observed that particle shape and structure of plastic pigment had influenced the rheology of coating color the state of packing and the properties of coated paper. Inorganic pigments used in this research were platelike kaolin clay and rhombic calcium carbonate. Three kinds of plastic pigments were blended with two inorganic pigments respec-tively. The combination of pigments were carried out(1) to determined the effect of particle structure of plastic pigment on the state of dispersion of coating color(2) to observe the effect of calendering temperature on the property of coated paper prepared with different plastic pigments. The data indicated that binder and hollow type plastic pigment gave the best results in improving the properties of coated paper such as paper gloss opacity and air pet-meability.

• Journal of the Korean Ceramic Society
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• v.20 no.3
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• pp.243-249
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• 1983

This study has examined on the effect for the fitting in porcelain body of MgO-SiO system. The mixture was made of correponding in the theoretical composition of enstatite with Kyul Sung Talc and sea water magnesia cake. Hyup Jin Kaolin as clay minerals to give the mixture plasticity was added 10% by weight of the mixture. Feldspar was added inv various kinds of 1%-20% by weight of the above mixture. After the physical properties and microstructures were carefully examined the following results were obtained. 1. The addition amount of feldspar should generally be from 5% to 10% by weight of the mixture to be good for the properties of the strength and the range of the firing temperature. 2. The 5% addition amount of feldspar was good for the apparent bulk density. 3. 5% and 10% additions showed up stably excellant with respect to the various properties Therefore when we considered the apparent bulk density and the thermal shock resistance 5% addition amount of feldspar showed the most excellant properties between $1350^{\circ}C$ and $1400^{\circ}C$.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.585-588
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• 2006

This paper presents experimental results for durability performance of GFRP composite exposed to the $80^{\circ}C$ alkali solution. A total of 280 specimens for 4 types of additive and 7 cases of immersion time were prepared and tested. Additives used in this study were PVA, kaolin clay, and alumina powder. Specimens were immerged up to 30 days and tested for tensile strength for each immersion time. The results indicate that it is important to fill the inner space of GFRP composite densely to avoid the decrease of tensile strength. In this study, PVA additive showed better performance than other additives.

• Journal of Pharmaceutical Investigation
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• v.2 no.1
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• pp.31-39
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• 1972

국산산성백토(國産酸性白土)를 정제(錠劑)의 붕노제(崩努劑)로 개발(開發)하고자 종내(從來) 붕해제(崩解劑)로 사용(使用)해 오든 corn starch, calcium methylcellulose, kaolin, calcium silicate 및 Pectin과 국산산성백토(國産酸性白土)를 붕해제(崩解劑)로하고 정제(錠劑)의 주약성분(主藥成分)으로서는 불용성(不溶性)인 Ca-PAS KP II 를 택(澤)하였다. 이상(以上)의 각(各) 붕해제(崩解劑)의 一錠當(일정당) 함양(含量)을 0%에서 25%까지 7종(種)으로 달리하고 이것을 각각(各各) 사용(使用)하여 만든 과립(顆粒)의 입자도(粒子度)도 각각(各各) 4종류(四種類)로 분류(分類)하였다. 여기에 활택제(滑澤劑) 로서 0.5% mg-stearate를 공통(共通)으로 첨가(添加)하였다. 이상(以上)을 각각(各各) 동일(同一)한 조건하(條件下)에서 타정(打錠)하여 수종(數種)의 정제(錠劑)를 만들었다. 이들 정제(錠劑)에 대(對)하여 경도(硬度)및 붕해도시험(崩解度試驗)을 하여 비교검토(比較檢討)한 결과(結果) 다음과 같은 결론(結論)을 얻었다. 1. Corn starch는 우수(優秀)한 붕해제(崩解劑)이나 그첨가량(添加量)이 8%이상(以上)이 될 때 는 타정시(打錠時) 압력(壓力)을 받지 않어 정제(錠劑) 붕해제(崩解劑)로서 사용(使用)할 수 없었다. 2. Ca-Mc는 붕해제(崩解劑)로서 첨가량(添加量)이 8%이상(以上) 일때에도 사용가능(使用可能) 하였으나 15%이상(以上) 일때는 타정시(打錠時) 압력(壓力)이 약(弱)해졌다. 3. Kaolin 붕해제(崩解劑)로서 부적당(不適當) 하다고 사려(思慮)되였다. 4. Ca-silicate도 붕해제(崩解劑)로서 적당(適當)하였으나 Pectin은 가장 부적당(不適當)하였다. 5. 산성백토(酸性白土)는 정제붕해제(錠劑崩解劑)로서 타정시(打錠時) 25% 첨가시(添加時)에도 압력(壓力)을 잘 받어 정제(錠劑)의 경도(硬度)를 유지(維持)할수 있었을 뿐만 아니라 붕해도(崩解度)도 양호(良好)한 성적(成績)을 나타내여 가장 우수(優秀)한 붕해제(崩解劑)임을 확인(確認)하였다. 6. 일반적(一般的)으로 타정(打錠)에 사용(使用)되는 과립(顆粒)의 size가 적을수륵 붕해시간(崩解時間)은 짧았으며 정제(錠劑)의 경도(硬度)가 높을수록 붕해시간(崩解時間)은 길었다. 그러나 정확(正確)한 비예성(比例性)은 찾기힘들었다.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.295-301
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• 1997

Among 120 microorganisms isolated from soil, KF-67 was the best producer of flocculant and was examined for flocculating ability in the kaolin clay and CaCl2 suspension. KF-67 was identified to be a species belong to the genus Agrobacterium sp. The influence of components of the culture medium for flocculant production by Agrobacterium sp. KF-67 was studied. The favorable carbon and inorganic nitrogen source for production of the flocculant were glucose and NH4NO3 and their addition concentrations were 2% and 0.1%, respectively. Addition of the organic nitrogen such as yeast extract, peptone and inorganic salt such as CaCO3 significantly increased the production of flocculant. These result indicated that the production of flocculant by Agrobacterium sp. was significantly affected by both organic nitrogen and inorganic salt. The components of the optimum culture medium were 2% glucose, 0.1% NH4NO3, 0.01% yeast extract, 0.01% peptone, 0.04% CaCO3, 0.03% NaCl in initial pH 7.5 when cultured with rotary shaker controlled at 3$0^{\circ}C$ and 120 rpm. Under the optimum culture medium, flocculant production was highly improved about 76% than that isolation medium.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.6
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• pp.193-204
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• 2008

This paper describes laboratory experiments modelling multiple tunnel construction in soft ground. A series of small-scale model tests have been conducted at approximately 1/50 scale in order to investigate the behaviours of existing tunnels in response to the construction of new tunnels in close proximity. The model tunnels were constructed in a consolidated Speswhite Kaolin clay using a tunnelling device involving an auger type cutter within a shield. Strain gauges and LVDTs were used for instrumenting the existing tunnels. The findings obtained from the analyses of these tests were compared to the field measurements involving the reconstruction of the Northern Line London Underground Ltd. tunnels at Old street, United Kingdom. The results were also compared to the ground movement measurements obtained from a separate set of tests undertaken using the same apparatus and experimental procedures.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.2
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• pp.89-97
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• 1986

To clarify the soil characteristics and genesis of the clayey terrace soils in Yeongnam area, the study were carried out with 9 typifying pedons of toposequential terrace soils in Yeongcheon (inland area) and Yeongil (coastal area) region. The results of soil genesis oriented investigations on soil mineralogical compositions and weathering characteristics were summarized as follows; 1. The contents of heavy minerals contained in sand fraction of the terrace soils were less than 5%, but the content in soil layers considered to be originated from other than terrace deposits had 9.8-16.2%. The content of feldspars in light minerals were higher in Yeongcheon sequence while the Yeongil sequence were characterized by having higher content in quartz. The ratios of quartz/feldspars in the soil layers where expecting lithological discontinuity, were different from that of terrace deposits. 2. The resistate index of maturity ranged around 76.7-29.9 in Yeongcheon area and around 85.6-67.2 in Yeongil area. The indices increased with the elevations of terraces. 3. The molar ratios of $SiO_2/Al_2O_3$ in clay fraction were around 1.93-2.65. The parent materials of the terrace deposits judged by the ratios of $Al_2O_3/TiO_2$ and $Fe_2O_3/Al_2O_3$ were considered to be the felsic materials. 4. The compositions of clay minerals detected by X-ray diffractogram and D.T.A. thermogram were dominated by kaolin and illite with subsidiary minerals of vermiculite, quartz, vermiculite intergrading to illite etc. It was distinguished from terrace deposits that by having higher amount of kaolin and montmorin minerals in the substrata of Bancheon soils in Yeongcheon area and Upyeong soils in Yeongil area, respectively.