• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.561-564
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• 2004

In this study, the properties of autogenous shrinkage and dry shrinkage for high performance concrete using Type I and Type IV cement were discussed. According to experimental results, autogenous shrinkage of SN30(the high performance concrete using type I cement) shows values higher than SL30( the high performance concrete using type IV cement). But the dry shrinkage of SN30 is almost the same as SL30. It is observed that the total shrinkage strain of SN30 is higher than that of SL30, because the ratio of autogenous shrinkage of the total shrinkage is relatively large. Therefore, SL30 is more effective to control or minimize the cracking of the high performance concrete, compared with SN30.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.307-311
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• 2006

Chemical analyses were conducted for Nakdong River water and riverbank filtrate in Daesan-Myeon area, Changwon City in 2005. Chemical components show different trends in wet season (June, July, August and September) and dry season (the other months). The patterns of chemical variation are classified into four types. Chemical components belonging Type I, as Na and $HCO_3$, show decrease in concentration during wet season and increase in concentration during dry season for both Nakdong River water and the riverbank filtrate. Chemical components belonging Type II, as Mg and $SO_4$, show decrease in concentration during wet season and increase in concentration during dry season for Nakdong River water while show the opposite trend for the riverbank filtrate. Chemical components belonging Type III, as Cl and $NO_3$, show increase in concentration from the start of wet season and high concentration during dry season for both Nakdong River water and the riverbank filtrate. Chemical components belonging Type IV, as Fe, show increase in concentration during wet season and decrease in concentration during dry season for both Nakdong River water and the riverbank filtrate.

• 조명전기설비학회논문지
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• 제30권1호
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• pp.72-78
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• 2016

In terms of power components which use environmentally-friendly dry air that can substitute SF6, there have been studies on the electrical properties of the solid insulation "spacer" for the purpose of securing dielectric strength as they become smaller. This study laminated solid insulation to keep the creeping distance the same in the dry air and investigated vertical surface discharge characteristics by shape. The three sheets of disk-type solid insulation(Bakelite) were laminated in a manner to keep the creeping distance the same. The lamination was categorized as follows: "Type A" in which the insulations with the same disk diameter were laminated; "Type B" in which the insulations whose middle disk diameter was large were laminated; and "Type C" in which the ones whose middle disk diameter was small were laminated. For a vertical surface discharge experiment, dry air was injected into the test chamber depending on the shape of the laminated solid insulation, and chamber pressure was adjusted in a range of 0.1-0.6MPa. As volume decreased, surface discharging voltage by unit volume increased. This was because of dielectric polarization according to the structural characteristics of the shape of lamination. The highest surface discharging voltage was found in "Type C."

• 동력기계공학회지
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• 제17권1호
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• pp.85-90
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• 2013

Dry CVT consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study ball type is proposed instead of roller type of movable flange to resolve the claim. Simulation is carried out for new model to verificate performance, experiments are carried out for new model to evaluate performances.

• 설비공학논문집
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• 제13권11호
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• pp.1049-1058
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• 2001

The performance and design analysis for a NWD cooling tower using a combined wet and dry type fill are numerically investigated and compared with the experimental results. The Stoecker's method is applied to the wet section and LMTD or NTU-Effectiveness method to the wet and dry sections. The efficiency ratio of the NWD cooling tower to a wet type crossflow cooling tower is 59.34%. The predicted result shows a good agreement with the experimental data within 1.4% error. Plume abatement is far better with a NWD cooling tower than a counterflow cooling tower. It costs less than a conventional wet/dry tower because the finned exchanger is eliminated. This method also leaves out complexity in structure and Intricacy in operation.

• 한국정밀공학회지
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• 제21권11호
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• pp.179-185
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• 2004

The effect of viscous damping on stability of beam resting on an elastic foundation subjected to a dry friction force is analytically studied. The beam resting on an elastic foundation subjected to dry friction force is modeled for simplicity into a beam resting on Kelvin-Voigt type foundation subjected to distributed follower load. In particular, the effects of four boundary conditions (clamped-free, clamped-pinned, pinned-pinned, clamped-clamped) on the system stability are considered. The critical value and instability type of columns on the elastic foundation subjected to a distributed follower load is investigated by means of finite element method for four boundary conditions. The elastic foundation modulus, viscous damping coefficient and boundary conditions affect greatly both the instability type and critical load. Also, the increase of damping coefficient raises the critical flutter load (stabilizing effect) but reduces the critical divergence load (destabilizing effect).

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1069-1085
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• 2011

In large-type goats that were fed on dry forage twice daily, dry forage intake was markedly suppressed after 40 min of feeding had elapsed. The objective of this study was to clarify whether or not increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding suppress dry forage intake. Eight large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 3 to 6 years, weighing $72.3{\pm}2.74$ kg) were used in two experiments conducted under sham feeding conditions. The animals were fed ad libitum a diet of roughly crushed alfalfa hay cubes for 2 h from 10:00 to 12:00 h during two experiments. Water was withheld during feeding in both experiments but was available for a period of 30 min after completion of the 2 h feeding period. In experiment 1, an intraruminal infusion of artificial parotid saliva (RIAPS) in the control replenished saliva lost via the esophageal fistula and an intraruminal infusion of hypertonic solution (RIHS) in the treatment was carried out in order to reproduce the effects of changing salt content due to feed entering the rumen. In experiment 2, the RIHS control was conducted in the same manner as the RIHS treatment of experiment 1. The treatment group consisted of RIHS-with an intravenous infusion of artificial mixed saliva (VIAMS) treatment that was carried out for 3 h to prevent increases in plasma osmolality during feeding. The results of the RIHS treatment in experiment 1 showed that ruminal fluid osmolality increased and then an increase in plasma osmolality was observed. This resulted in the production of thirst sensations and the reduction of cumulative dry forage intake to 43.3% (p<0.05) of the RIAPS control. The results of the RIHS-VIAMS treatment in experiment 2 indicated that ruminal fluid osmolality was the same as the RIHS control but plasma osmolality significantly decreased, and thirst level was markedly reduced. This caused a significant increase of 31.4% (p<0.05) in cumulative dry forage intake in the RIHS-VIAMS treatment compared to the RIHS control. These results indicate that increases in ruminal fluid osmolality during dry forage feeding indirectly suppresses dry forage intake by causing an increase in plasma osmolality and subsequently inducing thirst sensations. The results of the present study suggest that marked decreases in dry forage intake after 40 min of feeding are caused by increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding.

• 한국작물학회지
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• 제17권
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• pp.45-78
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• 1974

본 시험은 유ㆍ무한형대두품종에 대한다수성품종의 유종 및 재배기술개선의 기초자료로서 건물생산 및 제 형질간의 상호관계를 밝힐 목적으로 파종기, 재식밀도 및 시비수준이 다른 조건에서 광교, 동북태 및 수계5001를 유한형품종으로 그리고 Shelby, SRF-300 및 Harosoy를 무한형품종으로 하여 1972년부터 2개년에 걸쳐 작물시험장(수원)에서 실시하였는데 그 결과를 요약하면 다음과 같다. 1. 개화기에 있어서의 건물중, CGR 및 LAI는 품종, 파종기, 시비수준을 막론하고 밀식할수록 증가하였고 개화기가 빠른 무한형품종들은 유한형품종보다 현저히 떨어졌으나 정엽전개기에는 오히려 유한형보다 무한형이 더 높거나 거의 같은 수준을 나타냈다. 2. 파종기별로 본 개화기의 건물중은 유ㆍ무한형 모두 5월 21일구와 6월 15일구가 거의 비슷하나 7월 10일구의 건물중은 낮았으며 시비수준이 높을수록 개화기에는 CGR을 비롯하여 건물중과 LAI도 높았다. 3. 엽면적지수(LAI)는 동일군내에서 품종간차이도 상당히 컸으나 무한형품종은 파종기, 재식밀도 및 시비수준을 막론하고 유한형품종보다 떨어지는데도 종실수량은 별로 떨어지지 않았다. 4. 조식 및 증비의 경우에는 밀식을 하면 정엽전개기 이후에 엽과 엽병부분의 낙하가 많으나 소식인 경우 또는 만파(7월 10일)에서는 엽과 엽병의 낙하가 적은 경향이 뚜렷하였다. 5. 식물체부분별로 보면 경중비율은 밀식할수록 높아지고 반면 엽중비율은 소식할수록 높아졌으며 만파할수록 경중과 엽병비율은 떨어지고 엽중비율은 높아지는 경향이었다. 6. 정엽전개기에 있어서 유한형품종은 맥중비율이 5월 21일구에서 25내외, 6월 15일구에서 8%내외, 7월 10일구에서는 9%내외이어서 매우 적은 반면 무한형품종은 5월 21일구에서 6%내외, 6월 15일구에서 14%내외, 그리고 7월 10일구에서는 21%내외로 매우 컸다. 7. 광교는 다비조건에서 도복된 후에도 황화낙엽이 적고 생육이 회복되나 SRF-300은 생육이 회복되지 않았다. 8. 종실수량은 5월 21일구가 가장 높았으나 6월 15일구와 별로 차이가 없고 7월 10일구는 감소가 컸는데 유한형품종들은 만파에 의한 감소정도가 비교적 적고 무한형품종은 그 정도가 컸었다. 9. 재식밀도의 적정수준은 수량면으로 보았을 때 5월 21일구에서는 a당 1,250∼2500개체, 6월 15일구에서는 2,500개체, 그리고 7월 10일구에서는 3,333개체수준이었다. 10. 전품종에 있어서 정엽전개기의 건물중과 LAI 그리고 맥비만기의 건물중은 수량과 높은 상관을 나타냈고 유한형품종에 있어서 최고의 수량을 기대할 수 있는 건물중의 적정선은 개화기때에 a당 25kg, 정엽전개기때에 50kg내외였으며 무한형품종에 있어서는 맥비만기의 LAI는 4∼5, 그리고 맥비만기의 건물중은 a당 80kg내외이었다. 11. 밀식을 하면 경장은 커지고 경태와 분지 및 절수는 적어져서 주경비율이 높아지고 절간장이 길어졌다. 경중, 절수, 맥수 및 종실수량의 주경비율은 밀식할수록 그리고 만파한 것이 높았으며 무한형이 유한형보다 높았다. 12. 밀식 또는 만파의 경우에는 맥수나 종실수량의 주경비율이 높아서 주경의존도가 높은 품종이 유리한 것으로 보였다. 13. 개화기와 정엽전개기의 LAI는 유ㆍ무한형 모두 단위면적당 총절수, 건물중 및 건경중과 높은 상관을 보였고 개화기의 LAI는 유한형의 경장 및 a당 맥수와의 상관에는 유의차가 없었으나 무한형의 경장 및 a당맥수와는 고도의 유의상관을 보였다. 14. 건물중은 LAI외에 CGR, 경장 그리고 a당 절수, 맥수 및 건경중과 높은 상관을 보였으나 경태와는 유의적인 상관이 없었다. 15. 도복지수는 LAI, 건물중, 경장 및 건경중과 높은 유의상관이 있었고 경태와는 무한형품조에 있어서 고도의 부의 상관을 보였으나 유한형품종에서는 유의상관이 없었으며 유한형품종에서는 수량과 고도의 정의 상관을 보였다. 또한 도복지수는 주경의 평균절간장과 고도의 정의 상관이 있었다. 16. 100립중은 밀식 및 만파 그리고 무비조건에서 떨어지는 경향이었고 주경보다 분지의 100립중이 낮았다. 17. 단백질함량은 어떤 재배조건에서도 변화가 거의 없으나 지방함량은 만파할 때 감소하는 경향이 뚜렷하였다.

• 한국의상디자인학회지
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• 제21권4호
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• pp.213-220
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• 2019

The dry cleaning effect related to the type of soil and fiber was analyzed using silicone and alcohol-based solvents(ethyl alcohol, isopropyl alcohol, acetone) that are relatively safe for the human body and environment to improve the detergency of hydrophilic soils in dry cleaning system. Based on this analysis, an effective dry cleaning method to be carried out for improving the detergency according to the type of hydrophilic soils. After dry cleaning was performed using 20 types of artificial soiled fabrics consisting of 7 types of fibers and 4 types of hydrophilic soils, the detergency was measured and the results were compared and analyzed by solvents and fiber types. The results are presented as follows; first, the detergency of hydrophilic soils using silicone solvents showed a low rate of detergency. In particular, the tannin soil showed a lower level of detergency compared to the protein soil. Second, the detergency of hydrophilic soils using silicon solvents with dry soap differed in some detergency according to the soil and fiber types. Especially, the detergency of curry soil on cotton fabric showed significant improvement. Third, the protein soil was not removed from dry cleaning using alcohol-based solvents, but the effect of dry cleaning of curry soil on both cotton and polyester fabric was substantially improved. As a result, the elimination of blood soil is more effective in silicon solvents than in alcohol-based solvents. The removal of tannin soils may improve detergency by adding dry soap to silicon solvents or by using alcohol-based solvents as alternative solvents. The use of alternative solvents such as silicon and alcohol solvents can contribute to the environmental improvement of the dry cleaning industry, which uses petroleum-based solvents. It is also expected to provide consumers with the opportunity to choose eco-friendly and efficient dry cleaning methods.

• 한국조경학회지
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• 제33권1호
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• pp.71-80
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• 2005

In order to search for ecologically indicative characteristics on the street tree plots in Daegu area, plant communities and their floras were investigated. A total of 105 plots were collected and numerically analyzed by PCoA(Principal Coordinates Analysis). These plots were classified into 4 types containing 139 species, 97 genera, 42 families(including 37 exotic species): urban-dry type, urban-wet type, rural-dry type, rural-wet type. Habitat connectivity to the surrounding vegetation cover, extent and frequency of human impacts, and soil moisture recognizably were the main factors to allow the plots differentiation. Indicative species composition to these four types was generated as Eleusine indica-Eragrostis multicaulis-Oxalis corniculata to the urban-wet, Digitaria ciliaris-Eleusine indica-Eragrostis multicaulis to the urban-dry, Setaria viri-dis-Artemisia-Lactuca indica var. laciniata to the rural-wet, and Setaria viridis-Digitaria ciliaris-Erigeron canadensis to the rural-dry, respectively. Mean species number per plot for rural type was 2.5 times higher than for urban types. Street tree species representative to the rural-wet type is Zelkova serrata, which is a key species of potential natural vegetation in the alluvial land of Daegu area. Street tree plots were characterized by Eleusine indica showing the highest r-NCD value and also C4-assimilation grass plants. Views on the efficacy of the rural-wet type and the reinforcement of vegetation connectivity and soil moisture in rehabilitating street tree plots, are discussed.