• 한국농공학회논문집
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• 제54권5호
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• pp.69-77
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• 2012

Relative density, used to express dynamics condition of sand quantitatively, is measured by RI Test, Standard Penetration Test and Cone Penetration Test. Each measurement method has demerits, which is complicated or needs a specific analysis instrument and an analysis of expert. Also the ground is in wet condition commonly because of an unsaturated zone between a saturated zone and a surface, so the behaviour of the ground has different engineering properties unlike the dry ground and it diminishes accuracy of measuring relative density. In this study, the correlation between relative density and penetration of fall cone test in dry condition and wet condition with variation of water content was analyzed and a simple measuring method for relative density was suggested. As a result, there were difference of penetration between dry sands and wet sands, the correlation between relative density and penetration showed linear expression and relative density could be measured by the linear relation.

• 터널과지하공간
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• 제24권3호
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• pp.224-233
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• 2014

지하 하중 조건에서 암석물성이 변한다는 것은 잘 알려져 있다. 따라서 침수상태에 놓인 폐광산이나 폐공동에서의 하중에 따른 암석 물성변화와 일반적인 건조상태의 하중에 따른 물성 변화와의 관계에 대하여는 연구가 필요하다. 침수-하중 조건에서의 암석 물성 변화를 파악하기 위해 다양한 실험실 실험이 실시되었다. 암석에 가해지는 하중은 단축압축강도의 20~80%로 조절하였다. 침수 및 건조 조건에서 동일한 하중을 가할 경우 발생하는 암석의 열적, 역학적, 물리적 물성 변화를 비교함으로써 건조조건에 비해 침수조건에서의 물성변화가 더 크게 일어남을 알 수 있었다.

• 전기학회논문지
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• 제60권8호
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• pp.1560-1565
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• 2011

The environmental pollution caused by green-house gases such as $CO_2$ and $SF_6$ has been becoming the main issue of industrial society. Many developed countries are making efforts to minimize the amount of $CO_2$ emission come from the operation of high voltage electrical apparatuses. As a part of these efforts, 180 countries signed the Kyoto Protocol in 1997 to cut back on their green-house gas emissions. Nowadays, the study on the development of dry air insulated switchgear (DAIS) which is known as an eco-friendly electrical apparatus is in progress. A DAIS is advantageous for minimizing the effect of impurities and enhancing the dielectric characteristics over an air insulated switchgear (AIS) by applying constant pressure to an enclosed cubicle. Therefore, a study on the electrical insulation performance of dry air as a gaseous insulation medium is conducted in this paper to substitute a gas insulated switchgear (GIS) for DAIS. As results, it is verified that the AC dielectric characteristics of dry air are similar to those of air and the lightning impulse dielectric characteristics of dry air are superior to those of air at 1bar pressure condition. However, dry air is of inferior dielectric characteristics to $SF_6$ at 4bar pressure condition. Finally, it is suggested that the internal pressure of DAIS should be over 4bar pressure to develop a high voltage switchgear which has similar electrical performance to a conventional GIS. Also, the empirical formulae on calculating the maximum electric field intensity at sparkover of dry air are deduced by experiments according to pressures. It is expected that these results are helpful to design and develop a high voltage electrical apparatus.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제16권1호
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• pp.1-11
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• 2009

The notion of a BCK-algebra with supremum (briefly, sBCK-algebra) is introduced, and several examples are given. Related properties are investigated. We show that every sBCK-algebra with an additional condition has the condition (S). The notion of a dry ideal of an sBCK-algebra is introduced. Conditions for an sBCK-algerba to be an spBCK-algebra are provided. We show that every sBCK-algebra satisfying additional condition is a semi-Brouwerian algebra.

• 한국인쇄학회지
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• 제23권2호
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• pp.25-43
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• 2005

Generally, machine calendering are used change of paper surface properties. During machine calendering, dry paper passes between the rolls under pressure, thereby improving the surface smoothness and gloss. These improvements make the paper better suited for printing and decreasing problems during the printing, such as delayed dry and set-off. Then we investigated newspaper properties by the changing of machine calendering condition, and relationship printability. Properties of each samples were examined in accordance with KS and TAPPI standard test method i.e, basic weight, bulk density, thickness, porosity, opacity, brightness, smoothness and roughness. IGT printability tester was used to obtain ink requirement of newspaper, printed density and set-off. Results of in this study, we have proposed the optimizes range of newspaper calendering condition. Useful optimize calendering condition was pressure 55 kN/m, temperature $130^{\circ}C$.

• 펄프종이기술
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• 제37권5호통권113호
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• pp.63-69
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• 2005

This study was performed to introduce recently developed polyvinylamine as a wet-end process and paper strength improving aids. As a retention and drainage aids, high cationic charged polyvinylamine was more effective at the BCTMP and ONP stock condition than LBKP stock condition. As a dry tensile strength aid, dual system of polyvinylamine with anionic polyacrylamide was the best at the LBKP or ONP stock conditions. On the other hand, polyvinyl amine alone was better than dual system of polyvinylamine with anionic polyacrylamide at the BCTMP condition. As a wet tensile strength aid, polyvinylamine single system and dual system of polyvinylamine with anionic polyacrylamide were good at LBKP, BCTMP and ONP stock conditions. However, poly(aminoamide)-epichlorohydrin resin was good at LBKP and ONP stock conditions but efficiency of poly(aminoamide)-epichlorohydrin resin was remarkably decreased at BCTMP stock condition.

• 한국패류학회지
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• 제25권2호
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• pp.121-126
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• 2009

This study was performed to determine the effect of temperature condition on growth of juvenile abalone Haliotis discus hannai with the different feeds. Two types of feed (dry sea tangle and experimental diet) at water temperatures of 20 and $23^{\circ}C$, and 23 and $26^{\circ}C$ were applied to experimental abalone twice. Forty-five juvenile abalone averaging 10.1 g in the first feeding trial and 11.5 g in the second feeding trial were randomly stocked into 6 of 50 L plastic rectangular containers each. Fishmeal, soybean meal and shrimp head meal was used as the primary protein source in the experimental diet. And dextrin and wheat flour, and soybean oil were used as the primary carbohydrate and lipid sources in the experimental diet, respectively. The dry sea tangle and experimental diet were fed to abalone once a day at the ratio of 1.5-2.0% total biomass of abalone with a little leftover in each experimental condition. Weight gain of abalone was significantly affected by feed type, but not by water temperature in the first feeding trial. Regardless of water temperature, weight gain of abalone fed the experimental diet was significantly higher than that of abalone fed the dry sea tangle. However, weight gain of abalone was significantly affected by water temperature, but not by feed type in the second feeding trial. Weight gain was highest in abalone fed the experimental diet at $23^{\circ}C$, followed by abalone fed the dry sea tangle at $23^{\circ}C$, abalone fed the experimental diet and dry sea tangle at $26^{\circ}C$, which was lowest. Moisture and crude protein content of the edible portion of abalone was significantly affected by feed type, but not by water temperature in the second feeding trial. However, ash content of the edible portion of abalone was significantly affected by water temperature, but not by feed type. In considering these results, it can be concluded that the well formulated feed was superior to the dry sea tangle for growth of juvenile abalone, and water temperature conditions of 20 and $23^{\circ}C$ seemed to be better than $26^{\circ}C$ to improve weight gain of abalone.

• 한국잡초학회지
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• 제2권2호
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• pp.141-145
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• 1982

IAA의 종자침지처리(種子浸漬處理)에 의하여 수도(水稻)에 대한 CNP와 Butachlor의 약해(藥害)를 경감(輕減)시킬 수 있는 가능성(可能性)을 검토(檢討)하기 위하여 담수직파(湛水直播)와 건답직파조건(乾畓直播條件)에서 기초실험(基礎實驗)을 수행(遂行)하였다. 1. 담수직파조건(湛水直播條件)에서 IAA 0.1, 1.0, 10.0ppm 에 수도종자(水稻種子)를 침지처리(浸漬處理)하므로써 CNP와 Butachlor에 의한 수도피해(水稻被害)의 경감효과(輕減効果)가 나타남에 따라 수도(水稻)의 초장(草長) 및 건물중(乾物重)은 IAA 무처리(無處理)에 비하여 현저히 증가(增加)되었다. 2. 건답직파조건(乾畓直播條件)에서는 IAA 0.1, 1.0ppm에 수도종자(水稻種子)를 침지처리(浸漬處理)하므로써 수도(水稻)에 대한 CNP와 Butachlor의 피해(被害)는 크게 경감(輕減)되었다. 3. 담수조건(湛水條件)에서 Butachlor를 처리(處理)하거나 건답직파조건(乾畓直播條件)에서 CNP를 처리(處理)한 경우에 IAA의 약해경감효과(藥害輕減効果)는 더욱 현저한 경향(傾向)이었다.

• 한국축산식품학회지
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• 제33권6호
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• pp.752-756
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• 2013

This study was carried out to investigate the effect of cooking condition on the water-soluble flavor precursors relevant to postmortem glycogen metabolisms in various beef muscles from Hanwoo (Korean cattle). The loins, striploins, top rounds, and eye of rounds from 40-mon-old heifers were cooked in either with $100^{\circ}C$ water bath (wet-cooking) or $180^{\circ}C$ household electric oven (dry-cooking) until attained to about $80^{\circ}C$ of internal temperature before the measurements of amounts of macroglycogen, proglycogen, free glucose, and lactate. The macroglycogen and proglycogen contents were not significant differences in all beef muscles between the wet-cooking and dry-cooking treatments. Regardless of cooking condition, the both loin and top round had higher (p<0.05) two types of glycogen than the eye of round. The free glucose and lactate contents presented higher trends in the dry-cooking treatment compared with the wet-cooking treatment. The wet-cooked top round had higher (p<0.05) free glucose than the wet-cooked eye of round. Moreover, the top round contained the highest lactate content regardless of cooking condition. Consequently, it is considered that the dry-cooking treatment would be more beneficial to the flavor of cooked beef muscles than the wet-cooking treatment.

• 한국식품과학회지
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• 제5권4호
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• pp.235-239
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• 1973

마른김의 당류조성(糖類組成)과 이것의 저장중(中)의 변화(變化)를 GLC 및 GC-MS에 의(依)하여 조사검토(調査檢討)하였다. 1. 마른김의 당류(糖類)로서 glucose, galactose, inositol 및 floridoside의 4종(種)을 동정(同定)하였으며, 이중(中) inositol만은 peak의 불안정(不安定)으로 정량(定量)을 보유(保留)하였다. 2. Glucose는 저습도하(低濕度下)에서나, 고습도하(高濕度下)에서나 저장중(中)에 큰 변화(變化)가 없었다. galactose는 저습도하(低濕度下)에서는 큰 변화(變化)가 없었으나 고습도하(高濕度下)에서는 급격(急激)히 증가(增加)하여 저장전(前)의 10배량이상(倍量以上)에 달(達)하였다가 다시 감소(減少)하는 변화(變化)를 보였다. 3. Floridoside는 저습도하(低濕度下)에서는 서서(徐徐)히 감소(減少)하는데 비(比)하여, 고습도하(高濕度下)에서는 급속(急速)히 감소(減少)하여 galactose와는 극히 대조적(對照的)인 변화(變化)를 보였다. 4. 미동정성분중(未同定成分中) mass spectrum으로 보아 isofloridoside라고 추정(推定)되는 성분(成分)의 저장중(中)의 변화(變化)는 floridoside의 변화(變化)와 극히 유사(類似)하였다.